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69,881,331 | https://en.wikipedia.org/wiki/Storage%20bed | A storage bed is a multifunctional furniture consisting of a bed which utilizes storage space which often otherwise is lost, for example by having drawers on its underside or a mattress which can be flipped up to access a storage space beneath (not to be confused with a pull-down bed which can be mounted to a wall). It is an example of a storage furniture or multifunctional furniture, and can accommodate more efficient use of living spaces.
Types
A captain bed or captain's bed is a type of storage bed which in addition to having drawers beneath also usually has shelves above the mattress, for example at the headboard. A bed whose mattress has to be lifted to access the storage space is sometimes referred to as an ottoman bed, while a bed with drawers underneath is sometimes referred to as a drawer bed.
Compared to makeshift underbed drawers
Storage beds are usually dedicated furniture built from the ground up as a bed frame with drawers, and usually have drawer slides. Other types of beds may also make use of the storage under the bed, for example by using loose bed drawers or storage boxes (with or without wheels), but this does not necessarily make the bed a storage bed.
See also
Commode
Trundle bed
References
Beds | Storage bed | [
"Biology"
] | 252 | [
"Beds",
"Behavior",
"Sleep"
] |
69,881,829 | https://en.wikipedia.org/wiki/John%20Hinchley | John William Hinchley (1871-1931) was a chemical engineer who was the first Secretary of the Institution of Chemical Engineers.
Early life and education
Hinchley was born 21 January 1871 in Grantham, and studied at Lincoln Grammar School. From 1887 to 1890 he served an engineering apprenticeship at Ruston, Proctor and Company while attending science classes in the evening, being a prizewinner in chemistry, followed by a year as a science teacher. A national scholarship and the support of a friend enabled him to go to Imperial College, London where he graduated in 1895 with first class honours. He successfully sat the exam for a Whitworth Scholarship.
Career
After Imperial College, he went to Dublin to assist Professor John Joly with the development of colour photography. Returning to London he became assistant to a designer of acid plants and acetone production which stopped when his employer was killed in a road accident, so he became a chemical engineering consultant. In 1903 he went to Siam to be the technical head of the new Royal Mint of Bangkok, successfully developing a process melting 2.5 tons of silver a day and coinage to British Royal Mint standards. Back in London he was again a consultant, designing and erecting a variety of chemical plants.
In 1909 he was invited to give a series of 25 lectures on chemical engineering at Battersea Technical College, the first regular curriculum in the subject in the UK. These were popular, and in 1911 he was appointed lecturer in chemical engineering for two days a week at Imperial College, in 1917 becoming assistant professor, all the while continuing with his professional work, but passing on the course at Battersea. The same year he was promoted to the class of Fellows of the Institute of Chemistry. In 1926 he was made full Professor. The same year the article on Chemical Engineering in Encyclopedia Britannica was his work.
Institution of Chemical Engineers
George E. Davis proposed the formation of a Society of Chemical Engineers, but instead the Society of Chemical Industry (SCI) was formed. In 1918 Hinchley, who was a Council Member of the SCI, petitioned it to form a Chemical Engineers Group, which was done, with him as chairman and 510 members In 1920 this group voted to form a separate Institution of Chemical Engineers, which was achieved in 1922 with Hinchley as the Secretary, a role he held until his death.
According to the editor of Chemical Age just after his death, "The establishment, a few years later, of the Institution of Chemical Engineers was due to him perhaps more than any single person." The journal Nature described him as instrumental in its formation.
Personal life
It was while at Imperial College that he was introduced to a student at the Royal College of Art, Edith Mary Mason. She was later a member of the Royal Society of Miniature Painters, Sculptors and Gravers. They were married on 4 August 1903. She designed the Seal for the Institution of Chemical Engineers, which was executed by medallist Cecil Thomas, a fellow member of the same Royal Society.
While in Siam, he became a freemason and was involved in setting up the Imperial College Masonic lodge.
He died 13 August 1931 after a long illness. He was cremated at Golders Green Crematorium and the ashes scattered in the Garden of Rest, where there is now a memorial.
Legacy
The Institution of Chemical Engineers instituted an annual Hinchley Memorial Lecture in 1932 and a Hinchley Medal in 1943 for the most meritorious student of chemical engineering at Imperial College. The Medal continues, but is now directly awarded by the college.
References
Bibliography
British chemical engineers
History of the chemical industry
People from Grantham
Institution of Chemical Engineers
Academics of Imperial College London
Alumni of Imperial College London
People educated at Lincoln Grammar School
English Freemasons
1871 births
1931 deaths | John Hinchley | [
"Chemistry",
"Engineering"
] | 751 | [
"Chemical engineering organizations",
"History of the chemical industry",
"Institution of Chemical Engineers"
] |
69,882,384 | https://en.wikipedia.org/wiki/Baccharis%20intermedia | Baccharis intermedia is a species of shrub native to Chile. The species was first formally described by the botanist Augustin Pyramus de Candolle in 1836.
Distribution
This species is common on coastal hills of central Chile.
Natural hybridisation
It is observed in areas, in which the habitats of Baccharis linearis and Baccharis macraei overlap or come into close contact. It is a natural hybrid of the aforementioned species and is part of a homoploid hybrid swarm. The morphology is intermediate in all aspects and shows all variations from both extremes of the parental phenotypes to intermediate forms. This is due to the back-crossing of hybrids with the parent species. The intermediate morphology is also reflected in the specific epithet intermedia, which suggests this species is intermediate between others.
References
intermedia
Plants described in 1836
Taxa named by Augustin Pyramus de Candolle
Flora of Chile
Hybrid plants
Dioecious plants | Baccharis intermedia | [
"Biology"
] | 195 | [
"Hybrid plants",
"Plants",
"Hybrid organisms"
] |
69,882,474 | https://en.wikipedia.org/wiki/Ivar%20Werner%20Oftedal | Ivar Werner Oftedal (25 February 1894 – 30 May 1976) was a Norwegian mineralogist.
He was born in Larvik. He took his cand.real. degree in 1929 and the dr.philos. degree in 1941, both at the University of Oslo. After 29 years as a conservator at the University Museum, he was a professor of geology at the University of Oslo from 1949 to 1964, specializing in mineralogy, geochemistry and crystallography.
References
1894 births
1976 deaths
People from Larvik
Norwegian mineralogists
Norwegian geochemists
crystallographers
University of Oslo alumni
Academic staff of the University of Oslo | Ivar Werner Oftedal | [
"Chemistry",
"Materials_science"
] | 136 | [
"Crystallographers",
"Crystallography",
"Geochemists",
"Norwegian geochemists"
] |
69,883,674 | https://en.wikipedia.org/wiki/Josette%20Bellan | Josette Bellan (née Rosentweig) is a Romanian-French-American aerospace engineer and fluid dynamicist known for her research on turbulence in high-pressure reactions, and on the interactions between fluid dynamics and thermodynamics in these reactions. She is a senior research scientist at the Jet Propulsion Laboratory (JPL) and visiting associate in the Department of Mechanical and Civil Engineering of the California Institute of Technology (Caltech).
Education and career
Bellan is originally from Romania, and grew up under the communist government there. She was educated in France, earning a baccalauréat in 1964 after studying at the Lycée Jules-Ferry (Paris), and a master's degree in 1969 at the Paris University of Sciences.
She and her family visited Princeton University on a vacation in 1969, and she and her twin sister Larisse (who died in 1980) were encouraged to apply to Princeton for graduate study. They did, becoming the second and third women graduate students in Princeton's engineering school, after Genevieve Segol, a civil and geological engineer who also came to Princeton from France, and the first women in Princeton's graduate program in aerospace and mechanical engineering. At Princeton, the twins were supported by Zonta International through Amelia Earhart Fellowships, and their arrival at Princeton was reported in The New York Times and French newspapers. She earned another master's degree at Princeton in 1972, and, with her sister, completed her Ph.D. in 1974. Her dissertation was A Theory of Turbulent Combustion and Nitric Oxide Formation for Dual-carbureted Stratified-charge Engines, supervised by William A. Sirignano.
After continuing at Princeton as a postdoctoral researcher, Bellan joined the Jet Propulsion Laboratory in 1978. She was a lecturer in jet propulsion at Caltech in 1992, became a visiting associate there in 1995, and was Chancellor's Distinguished Lecturer at the University of California, Irvine from 1995 to 1996. She became a senior research scientist at JPL in 1997.
She is a citizen of both France and the United States.
Research
Bellan's research involves the simulation of reacting mixtures, and has shown the importance in these simulations of combining the effects of both fluid motion and heat transfer, down to the smallest levels of scale. Applications of this work include the development of bio-fuels, improving combustion efficiency in ground and aerospace vehicles and their effects on climate change, understanding the atmosphere of Venus, and modeling the interaction of rocket plumes with the surface of the Moon.
Privacy activism
A 2004 policy of the Bush Administration, Homeland Security Presidential Directive 12, led NASA to require background checks on scientists at JPL. Bellan became part of a group of JPL employees who filed a lawsuit in 2007 against the policy, claiming that the checks into her personal life were too intrusive and harmed the collegial atmosphere of JPL, that as contract employees rather than government employees they should not be subject to the same checks required of people who performed classified research, and that this sort of government intrusiveness, typical of the communist regime that Bellan grew up under, was inappropriate for a democracy. The case, NASA v. Nelson, went to the Supreme Court of the United States in 2010, but the court upheld the government policy.
After the loss, some employees left JPL, but Bellan remained and submitted her background information. It was rejected because she included a note stating that she was submitting the information under duress, and she was required to submit it a second time without the note. In a related incident in 2012, a NASA laptop containing the background check information and other personal information of approximately 10,0000 employees was stolen from an employee's car, and a representative of the employees from the previous suit announced plans to sue NASA over its incautious handling of their information. The issue continued to simmer through 2014, when Bellan and another dual-national researcher from Ireland were required to sign a loyalty oath to the US, which they argued went well beyond the requirements of the 2004 policy. After an intervention by congresswoman Judy Chu, the requirement was modified.
Recognition
In 2014, JPL gave Bellan their highest research award, the Magellan Award for Excellence, for her methods for simulating mixtures of particles and supercritical fluids. The American Institute of Aeronautics and Astronautics (AIAA) gave her their 2018 Pendray Aerospace Literature Award, "for widely reaching, seminal and outstanding publications on bio-fuels, sprays and high pressure flows to meet future challenges of Aeronautics and Astronautics combustion systems".
She was named a Fellow of the American Society of Mechanical Engineers in 1988, and
a Fellow of the American Institute of Aeronautics and Astronautics in 2008. She became a Fellow of The Combustion Institute in 2021, "for establishing fundamental models of turbulent multi-phase phenomena with the models relying on fluid mechanics coupled to non-equilibrium thermodynamics and chemistry".
References
External links
Year of birth missing (living people)
Living people
American aerospace engineers
American women engineers
French aerospace engineers
Romanian aerospace engineers
Romanian women engineers
Fluid dynamicists
Jet Propulsion Laboratory faculty
Fellows of the American Society of Mechanical Engineers
Fellows of the American Institute of Aeronautics and Astronautics
20th-century French women engineers
21st-century French women engineers
20th-century French engineers
21st-century French engineers | Josette Bellan | [
"Chemistry"
] | 1,082 | [
"Fluid dynamicists",
"Fluid dynamics"
] |
69,883,821 | https://en.wikipedia.org/wiki/Traditional%20Jewish%20chronology | Jewish tradition has long preserved a record of dates and time sequences of important historical events related to the Jewish nation, including but not limited to the dates fixed for the building and destruction of the Second Temple, and which same fixed points in time (henceforth: chronological dates) are well-documented and supported by ancient works, although when compared to the synchronistic chronological tables of modern-day chroniclers, belabored mostly by western scholars of history, they are, notwithstanding, often at variance with their modern dating system. Discrepancies between the two systems may be as much as 2 years, or well-over 100 years, depending on the event. Prior to the adoption of the BC / AD era of computation and its synchronization with the regnal years of kings and Caesars recorded in historical records, Jews made use of the earlier Seleucid era counting (also known as the Year of Alexander), or, in Hebrew, minyan li-šṭarōth ("era of contracts"), by which historical dates were marked, from the time of Alexander the Great.
In ordinary time-keeping, often one single, major event was used as a datum point for reckoning time, meaning, given the enormity of a certain event, historians would make note of how long time had passed since that very event in relation to some later event, as is also the case in Jewish chronology.
Brief history of chronology
The Greek historian Timaeus of Tauromenium (c. 365 BCE–260 BCE) introduced the system of reckoning by Olympiads. Nepos is generally acclaimed to have been the first Roman writer of chronography. He marks the birth of Alexander the Great in the 385th year after the foundation of Rome, giving also the names of the consuls for that year. Rome's founding, or what is known as "A.U.C.," ab urbe condita, "from the foundation of the city [of Rome]," is fixed by Nepos, as also by Polybius, as falling in "the second year of the seventh Olympiad," a year corresponding roughly with 751/0 BCE. Like ancient Hebrew writers of history, their delineations of imperial chronology were centered mostly around provincial, or local, history.
Josephus, when bringing down the regnal years of the Babylonian kings who feature highly in Israel's history, cites the third book of Berossus.
Manetho, who was a high priest and scribe of Egypt, copied down from the ancient Egyptian inscriptions a chronological list of eight early Persian kings for Ptolemy Philadelphus (266–228 BCE), beginning with Cambyses, the son of Cyrus the Great, and omitting only the magi's interim rule.
Suetonius's De vita Caesarum (Lives of the Caesars), Josephus's The Jewish War, and Epiphanius's On Weights and Measures (Syriac version), all have attempted to accurately portray the regnal years of the Roman emperors, and, despite their good efforts, there are still discrepancies between them. These variants will invariably lead to discrepancies in the accepted chronologies. In Jerome's Chronici Canones (Chronicle) which he completed in 381 CE, the first regnal year of Julius Caesar, the first Roman emperor: Romanorum primus Caius Iulius Caesar, is marked as 48 BCE, but which Jerome in his original document had written in Roman numerals and given only the number of the Olympiad for events, and no more. Indeed, the corresponding BCE dates which are now present in this work are only the additions of the modern editor, Rudolf Helm.
"For modern scholarship the problem," in E. J. Bickerman's words, "is 'how we know Caesar was assassinated on March 15, 44 BC[E].' Before 480 BC[E], no date can be precise in terms of the Julian calendar unless confirmed by astronomical phenomena." There is also considerable disagreement among scholarship as to when to reckon the beginning of Augustus Caesar's imperium.
Echoing these great difficulties in chronological notations, D. MacNaughton wrote: "Systems of ancient chronology, propounded even since the days of George Smith, have been many and various, and while in one year one date is assigned with an air of finality to a certain king, a few years later the date is abandoned as erroneous. These changes are natural." In fact, it has taken many hundreds of years for scholars to arrive at the dates that are now assumed to be accurate, as purported by Grafton in his book on "Joseph Scaliger," and where he shows how long it took for Roman consular dates (and archon dates, etc.) to be converted into BC/AD. All the ancient dating systems had to be aligned and converted into the modern system, and cross-referenced, and where others were not easily translatable.
For the chronologies of Babylonian kings up to the fall of Babylon, as well as the chronologies of Persian kings, beginning with Cyrus the Great, modern-day historians rely principally upon the work Ptolemy's canon.
Cornerstones in Jewish tradition
Amongst Jews, the era known as the Seleucid era has been used in antiquity to mark chronological events. It was used extensively by Sherira Gaon in the writing of his Iggeret. The practice of reckoning years by this system is mentioned in the Babylonian Talmud (Avodah Zarah 10a): "Said Rav Nahman: In the Diaspora, it is not permissible to count [the date in years] except only by the kings of the Grecians." Its usage was common throughout the Jewish world until the sixteenth century, and has been used by Yemenite Diaspora Jews as late as the 1940s, until their immigration to the Land of Israel. By their recollection of the current calendar year, it is shown to have started in the Fall (Tishri) of 312 BCE, which agrees with modern scholarship (312/311).
It is disputed, however, how Alexander the Great fits-in with this Hellenistic dating era. Talmudic exegete, Rabbeinu Chananel, following Seder Olam, alleged that the Seleucid era commenced in the 6th-year of the reign of Alexander the Great, and that there were 40 years from the building of the Second Temple (during the reign of the Persian king Darius the Great) until the 6th year of the reign of Alexander the Great, namely, in 312 BCE. According to Rabbeinu Chananel, this 40-year period marked the building of the Second Temple under Darius the Great in 352 BCE and the beginning of Grecian hegemony over Israel in 312 BCE. Modern-day chroniclers assign different dates for Alexander's reign. Modern-day chroniclers also contend that from Darius the Great who laid the foundation of the Second Temple to Alexander the Great there was a span of 190 years, rather than a mere 40 years.
According to Josephus, Alexander the Great died in the 114th Olympiad, after reigning 12 years. If so, the 114th Olympiad would have corresponded with about 326 BCE, or what was then 15 years before they began to make use of the Seleucid era counting! Others put his death in 323 BCE, 12 years before the start of the Seleucid era. It is said that the Jews started this system of reckoning the years, in recognition of Alexander the Great who passed through their country and who received warmly the Jewish High Priest who came out to greet him. Others say that the introduction of this new era was in commemoration of the year in which Seleucus I reconquered Babylon and got the dominion over Syria, which last opinion seems to be that of Josephus as well (cf. Antiquities 13.6.7.).
The advantage of the Seleucid era counting system is that historical dates marked in this era do not require later synchronization with the BC / AD era configurations based on kings' reigns, configurations added later by modern chroniclers when trying to fixate the regnal years of various kings. Rather, all that was required of the Seleucid era counting was to simply convert it into the date used in the Common Era, without consideration for the rest. While the Seleucid Era counting has been abandoned in the writing of legal deeds, promissory notes, court attestations, etc., it is still relied upon by all observant Jews when determining the 2nd Temple's destruction. It is also considered very reliable when seeking to determine dates of events in relation to the Common Era, making for a more precise fixation of an event.
Another reason for the popularity of the Seleucid era counting amongst Jews is that the commencement of the Seleucid era was seen as a key fixed point of reference, being, according to Seder Olam, 1,000 years after the giving of the law at Sinai, or, precisely one-thousand years after Israel's departure out of Egypt.
Typically, a Jewish date is only informative if it can be identified in relation to some other point of reference, in this case, usually another calendar. Today, however, Jews make use of the era known as Anno Mundi, the "era of creation," in their transaction of dates.
Second Temple: Its years of duration and year of destruction
Jewish tradition holds that the Second Temple stood for 420 years. The same Jewish tradition holds that the Second Temple was destroyed in the lunar month Av (August), in the year 68 of the Common Era (rather than in year 70), naturally implying that the Second Temple was built in the year 352 BCE. Since it was during the reign of the Persian king, Darius the Great (Darius b. Hystaspes), that the Second Temple was constructed (Ezra 6:15), in the sixth-year of his reign, the timeframe given for this Persian king in Jewish chronology (whose reign, accordingly, began in 358 BCE) stands at variance with the time-frame given for the same king in conventional chronology (who is said to have reigned between 521 BCE–486 BCE), a 163-year disparity.
Jews have traditionally held the view that the date in which they are to reckon the 2nd Temple's destruction is the year which preceded the 380th year of the Seleucid era, also known as the Year of Alexander (a date which corresponds to anno 69 CE). This means the destruction of the 2nd Temple fell out in the lunar month of Av in the 379th year of the Seleucid era counting (Year of Alexander), or what corresponds to anno 68 CE.
The two most ancient historical sources used to support this tradition are the Jewish historian Josephus, citing the Book of Maccabees, and the Aramaic Scroll of Antiochus (compiled, according to Saadia Gaon, by the elders of the Schools of Hillel and Shammai). The Scroll of Antiochus would have been written in the early first century CE, before Suetonius wrote his Lives of the Caesars. However, there is a proclivity among modern-day chroniclers to bypass these Jewish sources, in favor of others.
According to the Aramaic Scroll of Antiochus, from the Second Temple's rebuilding till the 23rd year of the reign of Antiochus Eupator, son of Antiochus Epiphanes who invaded Judaea, there had transpired 213 years in total (i.e. since the Second Temple's construction under Darius). Quoting verbatim from that ancient Aramaic record:
(Literal translation: In the twenty third year of his kingdom, in the two-hundred and thirteenth year of the rebuilding of this, God's house, he (Antiochus Eupator) put his face to go up to Jerusalem.)
This time period given for Antiochus Eupator's reign is taken in conjunction with another record mentioned by Josephus, in his Antiquities of the Jews (12.9.2.). Based on Josephus's record, who cites from the First Book of Maccabees (6:16), Antiochus Eupator began his reign after his father's death (Antiochus Epiphanes) in anno 149 of the Seleucid era (= 162 BCE). Twenty-three years into Antiochus Eupator's reign would have then been anno 172 of the Seleucid Era, or what was then 139 BCE. Since, according to the Scroll of Antiochus, the Second Temple had already been standing 213 years, this means that the Second Temple was completed in anno 352 BCE, being what was then the 6th year of the reign of Darius the king (i.e. Darius, the son of Hystaspes), the year in which the king finished its building according to Ezra 6:15. Jewish tradition, which assigns 420 years to its duration, means that its destruction occurred in 68 CE.
Although this date of the Temple's rebuilding largely disagrees with modern scholarship who base their chronologies upon the Babylonian Chronicles and its rebuilding in 516 BCE when Darius I was thought to have reigned, it has, nonetheless, long been held by religious Jewish circles as being accurate and reliable, since it is founded upon a tradition passed down generation after generation. Modern scholars seek to rectify this apparent disparity in time by saying that "the Darius in whose reign the Second Temple was built, was not Darius I, as is commonly supposed, but Darius II." In this case, the chronology thus established is in striking agreement with certain chronological data or implications in Josephus and rabbinic literature as well as the writing of a letter to Artaxerxes before Darius II's decree to rebuild () – Artaxerxes I ruled between Darius I and II. On the other hand, the first decree to rebuild occurred before Darius I, by Cyrus , and during Artaxerxes I's reign work was begun on rebuilding the city of Jerusalem during which a chamber of the temple is in use . If the Darius in whose reign the Second Temple was built was Darius I, the date of its construction must, of necessity, be pulled back earlier to 516 BCE.
Counter-arguments against Seder Olam
The Greek historian Herodotus lived from circa 484 BCE to 425 BCE, and wrote about the dynastic history of four Persian kings in nine books: Cyrus (557–530 BCE, Book 1); Cambyses (530–522 BCE, Book 2 and part of Book 3); Darius (521–486 BCE, the rest of Book 3 and Books 4,5,6); and Xerxes (486–479 BCE, Books 7, 8, 9).
One of the strongest counter-arguments that can be made against Seder Olam and its demarcations in time is that, if the Second Temple was completed in the 6th year of the reign of Darius the Great, as noted by the Hebrew scriptures (), and which Temple, according to Seder Olam, stood 420 years and was built in 352 BCE, this would put the Greek historian Herodotus as having written his Histories (compiled c. 430 BCE) long before the event detailing Darius's actions ever having taken place, or some 72 years before Darius the Great ever came to power. Based on the year in which Herodotus completed his Histories, and where he mentions Cyrus the Great as reigning 29 years, and his son Cambyses reigning 5 years, and Darius the Great reigning 36 years, this would point to a time much earlier than that presumed to have happened for these same events based on Seder Olam. These four kings were all before Herodotus died, as Herodotus could not possibly have written about kings that, according to the Seder Olam, supposedly lived after his time.
In conclusion, the terminus post quem for the Second Temple's construction would have been before Herodotus wrote his Histories. These arguments point to the primacy of Josephus' chronological timetable over those written in Seder Olam.
According to the Chronicle of Jerome, Herodotus became well-known in the 78th Olympiad, meaning, between 378 BCE–375 BCE, about 52–55 years after compiling his Histories.
Another difficulty with Seder Olam is in its chronological list of successive Babylonian and Persian kings (chapters 28–29), during the one-hundred years prior to the building of the Second Temple, and which stands in stark contrast to the earlier historical records for the same kings, as penned by Josephus who cites Berossus, as well as by Manetho and by Ptolemy of Alexandria in his Canon.
Seder Olam has contracted the Persian period into 34 years, explained by Rashi to mean the time span between the building of the Second Temple under Darius in 352 BC (according to Jewish calculations) and Alexander the Great's rise to power in 318 BCE. This time-frame, therefore, does not signify the end of the dynasties in Persia, but rather of their rule and hegemony over Israel before Alexander the Great rose to power. The difficulty besetting this explanation, however, lies in the fact that from Darius I who laid the foundation of the Second Temple to Alexander the Great, who brought an end to Persian hegemony over Israel, there are collected no less than 190 years. This would suggest that the author of Seder Olam confounded Darius I with Darius III Codomannus, the latter Darius being a contemporary with Alexander the Great.
Another variant argument against the priority of Seder Olam is that if there were only 34 years from Darius I to Alexander the Great, Haggai 1:1 informs its reader that the first high priest to officiate in the Second Tempe was Jeshua b. Josadek, and that this high priest was contemporary with Darius I. Josephus informs his readers that there was a succession of eight high priests from Jeshua b. Josadek to Simon the Just (see infra), which last high priest, according to the Talmud (Yoma 69a), was contemporary with Alexander the Great. Since the high-priesthood is passed down from father to son after the father's death, it strains credulity to think that, in only a short 34-year period, eight high priests served in that Temple. Even if one were to extrapolate from Josephus's words (Antiquities 11.8.4–5.) that Alexander the Great had actually met-up with the sixth line of high priests, namely, with Jaddua b. Jonathan, this would imply that each high priest served, on average, no longer than a little over 5.5 years. Contemporary chronology puts this same period at approximately 190 years, which, on average, makes each of the eight high priests serving for a period of about 24 years.
The Sabbatical year as a means to determine events
The Jubilee and Sabbatical year provided a long-term means for dating events. Unfortunately, the Jewish method of calculating the recurring Sabbatical year (Shmita) has been greatly misunderstood by modern chroniclers of history, owing to their unfamiliarity with Jewish practice, largely due to its being ensconced in the Hebrew language, and which has led to many speculations and inconsistencies in computations. According to Maimonides (Mishne Torah, Hil. Shmita ve-Yovel 10:7), during the Second Temple period, the seven-year cycle which repeated itself every seven years was actually dependent upon the fixation of the Jubilee, or the fiftieth year, which year temporarily broke off the counting of the seven-year cycle. Moreover, the laws governing the Jubilee (e.g. release of Hebrew bondmen, and the return of leased property to its original owners, etc.) were never applied all throughout the Second Temple period, but the Jubilee was being used during the period of the Second Temple in order to fix and sanctify thereby the Sabbatical year. A Sabbatical year could not be fixed without the year of the Jubilee, since the Jubilee serves to break-off the 7 x 7-year cycle, before resuming its count once again in the 51st year. While the 49th year is also a Sabbatical year, the fiftieth year is not the 1st year in a new seven-year cycle, but rather is the Jubilee. Its number is not incorporated into the seven-year cycle. Rather, the new seven-year cycle begins afresh in the 51st year, and in this manner is the cycle repeated. After the Temple's destruction, the people began a new practice to number each seventh year as a Sabbatical year, without the necessity of adding a fiftieth year.
According to Maimonides (1138-1205), the reckoning of the Sabbatical years and Jubilees was renewed in Israel when Ezra the Scribe came up to the land in the Temple's seventh year (346 BCE), and which same year became the 1st-year of the seven-year cycle, the first Sabbatical year being made seven years later when the Temple had stood for thirteen years. Maimonides, in his Responsa, repeats the same claims, but is less specific. Prior to Ezra's arrival, the Sabbatical years and Jubilee had been broken-off during the years of exile. This renewed counting, which Ezra initiated in the Temple's seventh year (six years after its rebuilding), happened to fall in anno 346 BCE, which year marked the 1st year of the new seven-year cycle.
Arguments in favor of the priority of this Jewish tradition are had in a statement made in the First Book of Maccabees, and later cited by Josephus in his Antiquities, where it is learnt that the "year 150 of the Seleucid dominion" was a Sabbatical year in the Land of Israel. This same year corresponds to the Fall of 162 BCE (lunar month Tishri), continuing unto the Fall of the following year in 161 BCE (lunar month Elul). By taking the year in which the seven-year cycle was reinstated in Israel with Ezra's return in 346 BCE (accounting for the adjustment of the Jubilee every 50 years and beginning anew the seven-year cycle in the 51st year), the year 162/161 BCE (being the 150th year of the Seleucid era) was, indeed, a Sabbatical year.
Other Sabbatical years mentioned by Josephus are anno 178 Seleucid era, corresponding with 134 BCE–133 BCE, and anno 271 Seleucid era, corresponding with 41 BCE–40 BCE, when Herod and Sosius captured Jerusalem, effectively ending the Hasmonean dominion. Moreover, according to Jewish tradition, the destruction of, both, the First and the Second Temple was in a post-sabbatical year, meaning, in the 1st year of the seven-year cycle. In all these cases, the dates of these events as brought down by conventional non-Jewish chronology cannot possibly coincide with the Sabbatical year and still be faithful to the Seleucid era counting. Only when viewed through the lens of Jewish tradition is there complete harmony in these dates.
Josephus's timeline of events
It is difficult to reconcile Josephus's history of the Second Temple period with that of rabbinic tradition, if not impossible. Although the Seleucid era dates and Olympiads penned by Josephus are, indeed, accurate (see infra) and do not contradict rabbinic tradition, Josephus's accounts of the Jewish high priests and the great span of time in which they all officiated would make the Second Temple appear to have stood six-hundred and thirty-nine years.
Josephus, in his historical works, often makes use of the Seleucid era counting to mark important events, as well as the Olympiad era. Occasionally, he will use both dating systems to describe a single event. The Seleucid era counting began in 312/11 BCE.
, and the 4th year of the 154th Olympiad
, and precisely 27 years before Herod the Great took the city.
.
.
Assuming that the year of the Second Temple's destruction is the same for both Josephus and Seder Olam, in 68 CE, the following discrepancies are irreconcilable:
Davidic line
Several vital clues are provided by the 2nd-century authors of Seder Olam and the Tosefta, as to the placement of events in relation to the Jubilee and seven year cycle. Although no dates are provided in ancient records, general time-frames for certain events are also provided by an inference to their relation to either the First Temple's building or to the First Temple's destruction, and which Temple is said to have stood 410 years. Since, according to Jewish oral tradition, the destruction of the First Temple occurred in 422 BCE, a year which also corresponded to the 1st-year of the seven-year cycle, scholars have sought to plot all events described in the Hebrew Scriptures based on these reference points. Other references include such facts (as brought down in Seder Olam) that the 11th-year of Solomon's reign, when he completed his building of the First Temple, was in the 4th-year of the seven-year cycle, or, similarly, that Jehoiachin's exile began 25 years before the next Jubilee and during the fourth year of a Sabbatical year, or that the 18th-year of Josiah's reign was the year of Jubilee, and that the 14th-year after the First Temple's destruction was also a Jubilee.
Moreover, the interval between the First Temple's destruction in 422 BCE and the Second Temple's destruction in 68 CE is put at 490 years.
In the Jewish custom of recollecting regnal years of kings, the 1st day of the lunar month Nisan marks a New Year for kings, meaning, from this date was calculated the years of the reign of Israelite kings; thus if a king was enthroned in the preceding month, Adar, he begins his second year of reign in the next lunar month, following the 1st of Nisan. Based on this unique way of reckoning regnal years, if King X died in the lunar month Nisan in the year 2022, and King XX succeeded him on the throne in Nisan of 2022, both kings are reckoned as having reigned one year in 2022. All dates provided in the following table showing King David's line of succession are, therefore, made subject to this caveat.
If the assumption is made that the date implicit in conventional chronology for the destruction of the First Temple is 586 BCE (instead of 422 BCE, as is found in rabbinic chronology), then 164 years should be added to all the dates in the "Seder Olam chronology" column showing David's dynasty.
Josephus's enumeration of High Priests during the Second Temple period
Josephus painstakingly listed the complete panoply of Jewish high priests who served during the Second Temple period and which, by comparison of dates when each man officiated as high priest, can be used as a time indicator to determine the span of time in which the Second Temple had its existence. It is of primary importance to note that Josephus, who claims that the Second Temple stood 639 years (approximately from 571 BCE), is consistent with his figures and demarcations in time all throughout his histories. For example, Josephus claims that from the Second Temple's building until the end of the tenure of the High Priest Menelaus (removed from office in 162 BCE), there had transpired 414 years, with a total of 15 high priests during that span of time (for an average tenure of 27.6 years per high priest), beginning with Jesus the son of Josadek, and ending with Menelaus. Indeed, a collection of these years amounts to a starting point for the Second Temple in around 576 BCE, within the margin of error for Josephus's figures.
Elsewhere, Josephus makes the remarkable claim that 471 years and 3 months had passed from the time that the exiles returned from the Babylonian captivity to the time that Aristobulus, the son of John Hyrcanus, began his reign as both king and high priest, the beginning of whose reign is put at c. 101 BCE. Indeed, a calculation of these years points to a time when the Jewish exiles were being resettled in the country in c. 572 BCE, one year before the year in which Josephus gives as the Temple's rebuilding in 571 BCE. In Josephus's Antiquities, the same period of en-masse Jewish immigration to the land of Israel after the Babylonian captivity is put at 481 years and 3 months prior to the reign of Aristobulus b. John Hyrcanus, or what would have been c. 582 BCE, some 11 years before the building of the Second Temple.
According to Josephus, there were a total of 83 officiating high priests from the founding of the Israelite nation under Moses and Aaron, the first high priest, until the destruction of the Second Temple. Of these, 28 high priests served the Jewish nation, over a span of 107 years, from Herod the Great until the temple's destruction. The following table, with its approximate dates, lists in chronological order the Jewish high priests that officiated in the Second Temple, from its foundation laid by Darius the Great unto its destruction in the 2nd year of the reign of Vespasian:
Josephus's timeline of high priests during the Second Temple period may have well been within a 420-year span of the Second Temple's existence (according to Seder Olam), although the same timeline given by Josephus does not strain credulity if it had spanned a 639-year period.
Disparities between Josephus and the Hebrew Scriptures
While in the vast majority of instances, Josephus's figures coincide with those of the Hebrew Bible, Josephus's figures given for certain events during the First Temple period often stand in direct contradiction to the figures given for the same event in the Hebrew Scriptures. For example, where the Hebrew Bible (I Kings 6:1) assigns 480 years from the exodus to the building of the First Temple, Josephus wrote (Antiquities 8.3.1.) that it was built 592 years after the exodus. Where the Hebrew Bible (I Kings 11:42) assigns Solomon's reign as 40 years, Josephus (Antiquities 8.7.8.) puts his reign at 80 years. Josephus also grossly erred in writing that a span of 514 years transpired from the time of the first and last kings of David's dynasty (being 21 kings altogether). The biblical accounts for this same period puts it at about 474 years. Whether they are copyist errors or not, such disparities cast a dark shadow on the reliability of Josephus's chronological timetable, since, in his own words, one of his expressed intentions was to convey the history of the Hebrews unto the Greeks, just as they are laid-up in the sacred writings. Many of Josephus's figures differ from those of Seder Olam, a chronography dating back to the 2nd century CE and where timeframes are more closely aligned to those of the Hebrew Bible, and largely accepted by the vast majority in Israel.
The year 68 CE as a focal point of reference
By counting in retrospect the regnal years of Caesars from this fixed point in time (68 CE), being, according to Jewish tradition, the year of the Second Temple's destruction and which came to its demise in the 2nd year of the reign of Vespasian, one is able to chart out and chronograph a rich past that might vary, in some respects, from the conventional views of modern-day chroniclers, as Josephus provides the avid scholar of history with a schematic chronology of the entire Second Temple period, with its successive chain of High Priests serving under the various rulers, with their respective tenures in office, as well as accompanied, occasionally, by dates inscribed in one of two epochs, the Seleucid era and the Olympiad era.
See also
List of High Priests of Israel
Missing years (Jewish calendar)
Chronology of the Bible
Timeline of Jewish history
Notes
References
Bibliography
(reprint of 1955 edition, Jerusalem)
(with endorsements by Rabbi Ovadia Yosef, Rabbi Shlomo Amar, and Rabbi Yona Metzger)
, Hil. Shmita ve-yovel 10:2–4
, responsum no. 389
Further reading
External links
Jewish chronology (Britannica), by E.J. Wiesenberg
Chronology
Hebrew calendar
Oral Torah | Traditional Jewish chronology | [
"Physics"
] | 6,847 | [
"Spacetime",
"Chronology",
"Physical quantities",
"Time"
] |
78,800,337 | https://en.wikipedia.org/wiki/Tardigrades%20in%20space | The use of tardigrades in space, first proposed in 1964 because of their extreme tolerance to radiation, began in 2007 with the FOTON-M3 mission in low Earth orbit, where they were exposed to space's vacuum for 10 days, and reanimated, just by rehydration, back on Earth. In 2011, tardigrades were on board the International Space Station on STS-134. In 2019, a capsule containing tardigrades was on board the Israeli lunar lander Beresheet which crashed on the Moon.
Tardigrades
Tardigrades are small arthropods able to tolerate extreme environments. Many live in tufts of moss, such as on rooftops, where they get repeatedly dried out and rewetted. Others live in the Arctic or atop mountains, where they are exposed to cold. When dried, they go into a cryptobiotic 'tun' state in which metabolism is suspended. They have been described as the toughest animals on Earth. Their DNA is protected from damage, such as by radiation, by Dsup proteins.
Proposals
In 1964, R.M. May and colleagues proposed that the tardigrade Macrobiotus areolatus would be a suitable model organism for space experiments because of its exceptional radiation tolerance.
In 2001, R. Bertolani and colleagues proposed tardigrades as a model for a study of animal survival in space. As terrestrial experiments on tardigrades proceeded, knowledge of their survival abilities grew, enabling K.I. Jönsson in 2007, and then other researchers such as Daiki Horikawa in 2008 and Roberto Guidetti in 2012, to present evidence that they would resist desiccation, radiation, heat, and cold, suiting them for astrobiological studies.
In 2008, F. Ono and colleagues suggested that tardigrades might be able to survive a journey through space on a meteorite, enabling panspermia, the transfer of life from one planet to another.
Missions
BIOPAN on FOTON-M3, 2007
Tardigrades have survived exposure to space. In 2007, dehydrated tardigrades were taken into low Earth orbit on the FOTON-M3 mission carrying the BIOPAN astrobiology payload. For 10 days, in the "Tardigrade Resistance to Space Effects" (TARSE) experiment, groups of Paramacrobiotus richtersi tardigrades, some of them previously dehydrated, some of them not, were exposed to the hard vacuum of space, or vacuum and solar ultraviolet radiation. Back on Earth, more than 68% of the subjects protected from solar ultraviolet radiation were reanimated within 30 minutes following rehydration; although subsequent mortality was high, many produced viable embryos.
In contrast, in the "Tardigrades in Space" (TARDIS) experiment, hydrated samples exposed to the combined effect of vacuum and full solar ultraviolet radiation had significantly reduced survival, with only three subjects of Milnesium tardigradum surviving. The space vacuum did not much affect egg-laying in either Richtersius coronifer or M. tardigradum, whereas UV radiation did reduce egg-laying in M. tardigradum.
The third FOTON-M3 experiment, "Rotifers, Tardigrades and Radiation" (RoTaRad) focused mainly on radiation survival.
LIFE prototype on STS-134, 2011
In 2011, Angela Maria Rizzo and colleagues sent tardigrades on board the International Space Station Endeavour along with extremophiles on STS-134, in the "Tardigrades in Space" (TARDIKISS) experiment. They concluded that microgravity and cosmic radiation "did not significantly affect survival of tardigrades in flight" and that tardigrades were useful in space research, with implications for astrobiology, where they should be suitable model organisms.
The mission was a prototype for the "Living Interplanetary Flight Experiment" (LIFE) which was to have travelled to the Martian moon Phobos on the Russian Fobos-Grunt spacecraft. The spacecraft however failed to leave Earth orbit and was destroyed.
Lunar lander Beresheet, 2019
In 2019, a capsule containing tardigrades in a cryptobiotic state was on board the Israeli lunar lander Beresheet which crashed on the Moon. They were described as unlikely to have survived the impact because the shock pressure of the crash would have been well above the 1.14 GPa that they have been measured as surviving. Despite tardigrades' ability to survive in space, they would still need food, lacking on the moon, to be able to grow and reproduce. The possibility that tardigrades survived the crash attracted concern about contamination of the Moon with biological material. However, they are unlikely to become rehydrated because of the lack of liquid water on the Moon.
References
Tardigrades
Space exposure experiments | Tardigrades in space | [
"Biology"
] | 1,012 | [
"Tardigrades",
"Space-flown life"
] |
78,800,412 | https://en.wikipedia.org/wiki/Envudeucitinib | Envudeucitinib is an investigational new drug that is being evaluated for the treatment of psoriasis. It is a selective tyrosine kinase 2 (TYK2) inhibitor developed by
Fronthera U.S. Pharmaceuticals LLC for the treatment of autoimmune diseases. Envudeucitinib targets the TYK2 signaling pathway, which plays a crucial role in regulating multiple pro-inflammatory cytokines such as IL-12, IL-23, and type I interferons.
References
Anti-inflammatory agents
Amides
Cyclopropanes
Methoxy compounds
Phenyl compounds
Pyridines
Triazoles | Envudeucitinib | [
"Chemistry"
] | 137 | [
"Pharmacology",
"Functional groups",
"Medicinal chemistry stubs",
"Pharmacology stubs",
"Amides"
] |
78,800,729 | https://en.wikipedia.org/wiki/Yoyo%20%28elephant%29 | Yoyo (Unknown - Barcelona, December 27, 2024) was an African elephant known as the world's longest-living elephant, who died at the Barcelona Zoo at approximately 54 years of age.
Biography
Before arriving at the zoo, Yoyo was rescued in 2009 after having spent time in a circus, which caused physical and psychological injuries that required specialized treatment.
She arrived at the zoo in 2009 as part of an international species conservation program, in which the center participates alongside the Government of Spain. Although her exact birth date is unknown, it is estimated that she was over 54 years old, while the average life expectancy for her species is 39 years.
She lived at the Barcelona Zoo with two other elephants.
See also
List of individual elephants
References
Oldest animals
Individual African elephants
Individual animals in Spain
2024 animal deaths
Circus elephants | Yoyo (elephant) | [
"Biology"
] | 167 | [
"Animals",
"Animal stubs"
] |
78,801,544 | https://en.wikipedia.org/wiki/Protocetraric%20acid | Protocetraric acid is a chemical compound with the molecular formula . It is a secondary metabolite produced by a variety of lichens and is classified as a depsidone.
History
In 1845 Knop and Schnedermann isolated crystalline cetraric acid from the lichen Cetraria islandica. O. Hesse proposed that cetraric acid does not exist in the lichen, but is rather the decomposition product of another acid that he called protocetraric acid, which is split up into fumaric and cetraric acids. In reviewing Hesse's work. O. Simon confirmed the statements of Knop and Schnedermann, finding cetraric acid in the plant in a free state. O. Simon did not find the protocetraric acid proposed by Hesse, but instead used that name for another acid he isolated.
Protocetraric acid was first described in the 1930s.
Rao and colleagues published the ultraviolet and infrared spectra of some lichen depsidones, including protocetraric acid, in 1967.
Properties
The molecular formula of protocetraric acid is C18H14O9; it has a molecular mass of 374.29 grams per mole. In its purified crystalline form, it exists as short needles with a melting point range of . Its ultraviolet spectrum has three peaks of maximum absorption (λmax) at 210, 238, and 312 nm. Its infrared spectrum has several peaks: 680, 745, 785, 814, 840, 990, 1020, 1080, 1115, 1150, 1190, 1270, 1380, 1440, 1562, 1642, 1738, 3000, and 3500 cm−1.
A number of ester derivatives of protocetraric acid, such as succinprotocetraric acid and fumarprotocetraric acid, have also been identified in lichens.
Preliminary research has been conducted into the potential pharmacology of protocetraric acid and related compounds. Protocetraric acid has broad spectrum antimicrobial properties against some pathogenic microbes such as Salmonella typhi. It also has weak activity against SARS-CoV-2 3C-like protease (Ki of 3.95 μM), as does the related depsidone salazinic acid, and therefore it is being studied as a scaffold for the potential discovery of more potent drugs for the treatment of COVID-19.
Biological activities
Laboratory experiments indicate that protocetraric acid has broad spectrum antimicrobial activity against some pathogenic microbes, including antibacterial activity against Salmonella typhi, and antifungal activity against Trichophyton rubrum. It also has moderate antimycobacterial activity on the growth of Mycobacterium tuberculosis.
Eponyms
Some authors have explicitly named protocetraric acid in the specific epithets of their published lichen species, thereby acknowledging the presence of this compound as an important taxonomic characteristic. These eponyms are listed here, followed by their author citation and year of publication.
Usnea hossei var. protocetrarica
Hypotrachyna protocetrarica
Karoowia protocetrarica
Myriotrema protocetraricum
Ocellularia protocetrarica
Opegrapha protocetrarica
Oropogon protocetraricus
Xanthoparmelia protocetrarica
Several derivatives of protocetraric acid were designed and synthesised using Diels-Alder reaction, esterification, and Friedel-Crafts alkylation of protocetraric acid with different reagents under Lewis acid. The products were tested for their α-Glucosidase inhibitory using molecular docking analysis.
Related compounds
The related chemical 9'-(O-methyl)protocetraric acid was isolated from the lichen Cladonia convoluta. Conhypoprotocetraric acid, identified from lichens Relicina cf. incongrua and Lecanora myriocarpoides, was synthesized and characterized in 1995.
Confumarprotocetraric acid
Conhyopoprotocetraric acid
Conprotocetraric acid
Consuccinprotocetraric acid
Fumarprotocetraric acid
Hypoprotocetraric acid
Malonprotocetraric acid
4-0-Methylhypoprotocetraric acid
Succinprotocetraric acid
References
Cited literature
Lichen products
Lactones
Heterocyclic compounds with 3 rings
Benzodioxepines
Benzoic acids | Protocetraric acid | [
"Chemistry"
] | 965 | [
"Natural products",
"Lichen products"
] |
78,802,451 | https://en.wikipedia.org/wiki/Endosulfan%20tragedy%20in%20Kerala | Endosulfan tragedy in Kerala is a series of health problems that occurred in Kerala, India, following the use of the pesticide endosulfan. Endosulfan was sprayed aerially in cashew orchards in Kasaragod district of Kerala to control pests such as tea mosquito bugs. It was found that people living in these areas were affected by physical and genetic problems after the application of this pesticide. The health effects of the spraying of endosulfan were evident in the people of 11 panchayats in the district, with the victims suffering from birth defects, physical disabilities, mental retardation, and gynecological problems. It also affected biodiversity of the region.
In April 2011, the Persistent Organic Pollutants Review Committee, a subsidiary body to the Stockholm Convention declared endosulfan molecule as a persistent organic pollutant. One reason for this declaration was the campaign launched by various stakeholders in the context of the health problems seen in Kasaragod.
Overview
During 1963–64, the Agriculture Department started planting cashews in the hills around Padre, which is now in Kasaragod district. In 1978, the plantations were taken over by Plantation Corporation of Kerala (PCK), a subsidiary of the Kerala government.
Endosulfan is an organochlorine insecticide and acaricide, which acts by blocking the GABA-gated chloride channel of the insect (IRAC group 2A). Endosulfan was aerially sprayed over the cashew orchards under the Plantation Corporation, in 1978, after a trial in 1977–78. It was used to control the tea mosquito bugs that affects cashews. Endosulfan was sprayed from helicopters three times a year. Later, it was found that people living in these areas were affected by physical and genetic problems after the application of this pesticide. These health problems have been reported mostly in panchayats like Enmakaje, Bellur, Kumbadaje, Pullur and Periye in Kasaragod district of Kerala. It is said that after almost 20 years of continuous aerial spraying of endosulfan pesticide in these panchayats, the local residents started succumbing to various diseases and deaths.
Consequences
In 1981, Sripadre, an independent environmental journalist, first exposed the consequences of the large-scale use of the pesticide endosulfan by reporting on various disorders among domestic animals in areas sprayed with the pesticide. On December 25, 1981, Evidence Weekly published a report on cows giving birth to calves with deformed limbs after aerial spraying of endosulfan in Enmakaje.
It was later discovered that the use of endosulfan also had a significant impact on humans. The health effects of the spraying of endosulfan were evident in the people of 11 panchayats in the district, with the victims suffering from birth defects, physical disabilities, mental retardation, cancer, and gynecological problems. Similar to Kerala, the same health problems are now being seen in the South Canara district of Karnataka, where the Karnataka Cashew Development Corporation aerially sprayed endosulfan on cashew orchards for over 20 years. Since 1995, 500 deaths have been officially recognized as being related to the spraying of endosulfan.
Following widespread public opposition, in 1998, the Kerala government temporarily suspended aerial spraying of endosulfan. In February 2001, a government-appointed team from the Kerala Agricultural University recommended an immediate halt to aerial spraying. Government imposed a permanent ban of this pesticide following a lower court ruling in 2001. In January 2002, the National Institute of Occupational Health released a report stating that they had found traces of endosulfan in water samples and blood samples collected from the village of Padre. A study published in 2018 found that endosulfan residues persist in Kasaragod soil even 20 years after its use was stopped.
In 2001, following media reports that spraying of the pesticide endosulfan in Kasaragod district had caused serious health problems, the National Human Rights Commission (NHRC) asked the Indian Council of Medical Research to study the matter and submit a report in July. In 2002, one of its constituent institutions, the National Institute of Occupational Health (NIOH), conducted a study on the subject and reported that the prevalence of the disease was higher in these areas. Following this, the commission urged the central government to impose a ban on endosulfan across India.
Although India government opposed a global ban of endosulfan, in April 2011, the Persistent Organic Pollutants Review Committee declared endosulfan molecule as a persistent organic pollutant. One reason for this declaration was the campaign launched by various stakeholders in the context of the health problems seen in Kasaragod.
The Kerala State Health and Family Welfare Department classified 6278 individuals suffering from various types of diseases as "endosulfan victims" and the deaths that occurred in the said areas at that time as "endosulfan poisoning victims". In this way, all those suffering from various diseases caused by endosulfan were included in the list of victims and they were provided with financial assistance, monthly pension, free ration, free treatment, housing and many other facilities. In 2006, the government distributed Rs.50,000 each to the dependents of 135 persons who died of endosulfan.
The spraying of endosulfan in cashew orchards has also caused significant damage to the biodiversity of the area, according to a study conducted by Dr. V.S. Vijayan of the Salim Ali Foundation. A rapid survey conducted by Vijayan and his team indicated that the use of the pesticide resulted in a 40 to 70 percent reduction in plant diversity in the area, and it affected native species, especially fish, being the most. Studies have also found declines in numbers and distribution of butterflies, which are considered biological indicators of healthy and diverse ecosystems.
Objections
There is controversy over whether endosulfan is the main cause of health problems in these areas. One argument is that it has not been proven that these diseases are more prevalent in Kasaragod than in other areas. It is also said that diseases that have nothing to do with endosulfan are also being attributed to it.
Scientist and head of the Department of Agricultural Entomology at Kerala Agricultural University, Dr. K. M. Sreekumar has spoken out strongly about the unscientific nature of the endosulfan disaster claims. Sreekumar says that the child with the enlarged head, which is said to be caused by endosulfan, was due to a disease called hydrocephalus, and that it can be caused by various reasons, such as difficulties during normal childbirth, problems that occur when two children are born together, etc. He adds that there is not even a research paper yet that this is caused by endosulfan. He says that these patients are present in areas where endosulfan has been sprayed and in areas where endosulfan has not been used so far, and that all types of diseases that have been shown to be caused by endosulfan in Kasaragod district are similar. He points out that while health workers are identifying patients who say they are due to endosulfan, there is a lack of clinical or biochemical evidence to confirm that these illnesses are a result of endosulfan.
Although a study by Calicut Medical College spot a high incidence of disease in Kasargod, according to a critique by Sreekumar and fellow entomologist Prathapan Divakaran, published in the journal Current Science, the levels of endosulfan in the blood of patients in the Calicut Medical College study appeared to have no correlation with the health of these patients.
Legal actions
Leela Kumari Amma, an agricultural officer from village of Pullur in Kasaragod, was the first to approach the court regarding endosulfan ban. On October 18, 1998, she filed a case in the Hosdurg Munsif Court demanding a halt to the spraying of endosulfan, and the court issued an interim order not to spray endosulfan in that area. When the Munsif Court order came, the Plantation Corporation moved the case to the Kanhangad Sub Court, but she won there too. After that, the Corporation moved straight to the High Court, but rejecting this, in 2000, the Kerala High Court upheld the lower court's order and permanently stopped the spraying of endosulfan. In 2011, Supreme Court of India banned production, sale and use of Endosulfan in the country till further orders.
In January 2017, the Supreme Court of India ordered state government to give a compensation of Rs 5 lakh each to the victims of endosulfan. In May 2022, after the government failed to distribute compensation to everyone even after five years of the order, Supreme Court has strongly criticized the state government for delaying the distribution of compensation to endosulfan victims.
The Supreme Court had ordered in 2017 that adequate medical facilities should be provided to endosulfan victims. However, following a contempt petition filed in the Supreme Court in 2021 alleging that the state had failed to implement this, the Kerala High Court directed the Kasaragod District Legal Services Authority (DLSA) to submit a detailed report on the medical and palliative care facilities for endosulfan victims in the district.
In popular culture
Arajeevithangalkkoru swargam () is a documentary film directed by M. A. Rahman that highlights the seriousness of the Endosulfan disaster. Produced by 'Greenfox' under the leadership of K.M.K. Kunjabdulla, the documentary began shooting in 1999 and was completed in 2002. A Pestering Journey, directed by K. R. Manoj, is another documentary based on this tragedy. This documentary was also submitted before the Supreme Court of India as evidence in the Endosulfan case.
Enmakaje (Translated as Swarga in English), a novel written by Ambikasuthan Mangad is based on the Endosulfan tragedy in Kasaragod. Valiya Chirakulla Pakshikal (), a 2015 Malayalam drama film written and directed by Dr. Biju is also based on this incident. Pakarnnattam, directed by Jayaraj is also based on this incident.
References
Health disasters in India
Chemical disasters
Disasters in Kerala
Toxic effects of pesticides | Endosulfan tragedy in Kerala | [
"Chemistry"
] | 2,159 | [
"Chemical accident",
"Chemical disasters"
] |
78,803,891 | https://en.wikipedia.org/wiki/Estrella%20Alabastro | Estrella Fagela Alabastro (born February 19, 1941) is a Filipina chemical engineer who served as Secretary of Science and Technology.
Early life and education
She obtained a BS in chemical engineering from University of the Philippines Diliman. She obtained an MS and PhD in chemical engineering from Rice University.
She is married to Edgardo Garcia Alabastro and they have three children.
Career
She researched thermal processing of Philippine food products and irradiation to extend the shelf life of mangoes. She created the Small Enterprises Technology Upgrading Program, which prolonged tinapa preservation from a week to 6 months.
She was responsible for the Food Science Doctoral Program at the University of the Philippines Diliman.
Alabastro was appointed Secretary of the Department of Science and Technology (DOST) March 12, 2001, serving until June 30, 2010. She was the first woman DOST Secretary.
In 2015, she was named Academician of National Academy of Science and Technology in Chemical Engineering.
References
1941 births
Living people
Secretaries of science and technology of the Philippines
Arroyo administration cabinet members
Chemical engineers
Women chemical engineers
20th-century Filipino engineers
Filipino women engineers
Members of the Filipino National Academy of Science and Technology
University of the Philippines Diliman alumni
Rice University alumni
Academic staff of the University of the Philippines Diliman | Estrella Alabastro | [
"Chemistry",
"Engineering"
] | 259 | [
"Chemical engineering",
"Women chemical engineers",
"Chemical engineers"
] |
78,805,142 | https://en.wikipedia.org/wiki/Nancy%20Johnson%20%28engineer%29 | Nancy L. Johnson is an American automotive engineer and materials scientist. She works for General Motors Research and Development as a lab group manager and technical fellow, and co-directs the General Motors / University of Michigan Smart Materials and Structures Collaborative Research Laboratory. Her work at General Motors involves the use of composite materials and smart materials in automotive applications.
Johnson became a Fellow of the American Society for Composites in 2003. She has chaired the Aerospace Division of the American Society of Mechanical Engineers (ASME), and was named as an ASME Fellow in 2005. She was the 2019 recipient of the ASME Adaptive Structures and Material Systems Award.
References
Year of birth missing (living people)
Living people
American automotive engineers
American women engineers
Women automotive engineers
American materials scientists
Women materials scientists and engineers
General Motors people
Fellows of the American Society of Mechanical Engineers | Nancy Johnson (engineer) | [
"Materials_science",
"Technology"
] | 167 | [
"Women materials scientists and engineers",
"Materials scientists and engineers",
"Women in science and technology"
] |
78,805,204 | https://en.wikipedia.org/wiki/HD%20194937 | HD 194937 (HR 7820; 7 G. Delphini) is a star located in the equatorial constellation Delphinus, the dolphin. It has an apparent magnitude of 6.23, making it barely visible to the naked eye even under ideal conditions. Gaia DR3 parallax measurements imply a distance of 367.5 light years and it is currently drifting closer with a heliocentric radial velocity of . At its current distance, HD 194937's brightness is diminished by an interstellar extinction of 0.24 magnitudes.
HD 194937 has a stellar classification of G9 III, indicating that it is an evolved G-type giant star that has ceased hydrogen fusion at its core and left the main sequence. The object has 1.51 times the mass of the Sun but at the age of 2.88 billion years, it has expanded to 9.68 times the radius of the Sun. It radiates 52.6 times the Sun's luminosity from its enlarged photosphere at an effective temperature of , giving the star an orange hue when it is viewed in the night sky. HD 194937 is slightly metal deficient with an iron abundance 93.3% of the Sun's and it spins slowly with a projected rotational velocity of .
References
G-type giants
Delphinus
Delphini, 7
BD+07 04477
194937
100953
7820 | HD 194937 | [
"Astronomy"
] | 288 | [
"Delphinus",
"Constellations"
] |
78,806,275 | https://en.wikipedia.org/wiki/NGC%20846 | NGC 846 (also known as NGC 847) is a barred spiral galaxy located around 235 million light-years away in the constellation Andromeda. NGC 846 was discovered on November 22nd, 1876 by the French astronomer Édouard Stephan, and it has a diameter of around 162,000 light-years. NGC 846 is not known to have much star-formation, and it is not known to have an active galactic nucleus.
Supernovae
Two supernovae have been observed in NGC 846:
SN2003ja (typeII, mag. 17.1) was discovered by the Lick Observatory Supernova Search (LOSS) on 22 October 2003.
SN2009fu (typeIa, mag. 15.7) was discovered by Kōichi Itagaki on 1 June 2009.
See also
List of NGC objects (1–1000)
References
External links
0846
02090+4420
008430
+07-05-024
Andromeda (constellation)
18761122
Barred spiral galaxies
01688 | NGC 846 | [
"Astronomy"
] | 213 | [
"Andromeda (constellation)",
"Constellations"
] |
78,806,557 | https://en.wikipedia.org/wiki/C/1905%20X1%20%28Giacobini%29 | Giacobini's Comet, also known as C/1905 X1, is a bright parabolic comet that became visible to the naked eye in January 1906. It is one of 12 comets discovered by French astronomer, Michel Giacobini.
Observational history
While observing at the Nice Observatory in France, Michel Giacobini discovered the comet as an 8th-magnitude object within the constellation Boötes. Throughout December 1905, the comet continued to brighten as it slowly approached both the Earth and the Sun, allowing follow-up observations to be conducted.
References
Notes
Citations
External links
Non-periodic comets
Hyperbolic comets | C/1905 X1 (Giacobini) | [
"Astronomy"
] | 127 | [
"Astronomy stubs",
"Comet stubs"
] |
78,806,704 | https://en.wikipedia.org/wiki/B2%201308%2B326 | B2 1308+326 known as OP 313 or AU CVn, is a BL Lacertae object located in the constellation of Canes Venatici. It has a redshift of (z) 0.997 and was initially discovered as a variable star in 1959 before being identified with its optical counterpart in 1972. Its radio spectrum is flat, making it a FRSQ (flat-spectrum radio quasar).
Description
B2 1308+326 is found variable on the electromagnetic spectrum. It is classified a blazar although some studies described it as a transitional or change-looking due to it experiencing a shift in synchrotron peak frequencies. It is known to show an outburst in 1978 which it displayed extreme degrees of polarization, found rapidly variable in both position and degree angles on a time scale for 15 minutes.
A gamma ray flare was detected in 2014. In June 2022, B2 1308+326 showed an optical flare, subsequently reaching a historic maximum brightness with a slight decreased flux of 0.2-0.3 magnitude in R-band observed a month later. Significant gamma ray activity was detected on 1 December 2023.
Radio imaging of B2 1308+326 made by Very long baseline interferometry at 5 GHz showed it has an extended region and simple radio core structure measuring 1.3 x 0.6 in size with an orientation along the 30° position angle. When shown at 8.4 GHz, the source is then resolved into a bright core with a brightness temperature of 1012 Kelvin and a jet structure. Subsequent observations found the core has a 3% polarization with a flat spectrum and contains perpendicular electric field vectors to the jet's direction which turns almost parallel upon 2 mas from the core. Imaging by Very Large Array showed it has a dominant component and secondary component located 12 arcseconds north as well as a diffused halo surrounding the structure.
A light curve of B2 1308+326 during 10 years between 1976 and 1986, its total range of variability was shown to be 3.0 magnitude with the detection of multiple flares. According to observations in early 1987, it was found to be a faint state indicating the light curve showed an overall decline. The light curve at 4.8–90 GHz frequencies also showed B2 1308+326 had two complex outbursts, one between 1980-1988 and the second between 1988 and 2001 accompanied by three flares.
References
External links
B2 1308+326 on SIMBAD
B2 1308+326 on NASA/IPAC Database
BL Lacertae objects
Blazars
OVV quasars
Quasars
Canes Venatici
Astronomical objects discovered in 1959
Active galaxies
F13080+3237 | B2 1308+326 | [
"Astronomy"
] | 559 | [
"Canes Venatici",
"Constellations"
] |
78,808,278 | https://en.wikipedia.org/wiki/Ralf%20Riedel | Ralf Riedel (born February 11, 1956) is a German professor of Materials Science at the Technical University of Darmstadt (TU Darmstadt) in Germany. He is known for his contributions to ceramics, polymer-derived ceramics (PDCs), and high-performance materials, which has advanced the understanding and application of ceramic materials in fields such as aerospace, automotive, and energy technologies.
Early life and education
Riedel studied chemistry at the University of Stuttgart with his Diploma Thesis concerning "Versuche zur Reduktion von Aldehyden mit weißem Phosphor". From 1984, he pursued a Ph.D. in the field of Inorganic Chemistry at the University of Stuttgart. In 1986, he graduated with his dissertation .
After education, Riedel undertook postdoctoral research at Max Planck- Institute for Metals Research, Institute for Materials Research, PML, Stuttgart in materials processing and characterization techniques. Between 1986 and 1992, he worked on his habilitation concerning "Nicht-oxidische Keramiken aus anorganischen Vorstufen" under supervision of Prof. Dr. G. Becker and Prof. F. Aldinger.
Career
Riedel was establishing and leading the Dispersive Solids Group at the Institute of Materials Science, Technical University of Darmstadt (TU Darmstadt) as professor from 1993 until his retirement in 2022. His research in the Dispersive Solids Group focused on the development of polymer-derived ceramics, high- temperature materials, and functional ceramics for structural and electronic applications.
Ralf Riedel's career spans several decades with contributions to materials science, particularly in the development and application of polymer-derived ceramics (PDCs) as well as high pressure materials synthesis. His work bridges theoretical research and practical applications. Below is a detailed exploration of his professional journey.
Research contributions
Riedel´s early research focused on developing ceramic materials through synthesis routes, Highlights of Riedel´s research at the Dispersive Solids Group are as follows:
Polymer-derived ceramics (PDCs)
Riedel is known for his work on PDCs. He has developed methods to design ceramics at the molecular level, enabling the production of materials with tailored properties. These advances have applications in high-performance coatings, lightweight structural materials, and energy storage technologies. His research into PDCs has been on extending their use to fields like aerospace engineering and microelectronics.
High-Temperature Ceramics
Riedel's work on ceramics designed for high-temperature environments has advanced the understanding of the thermal stability, creep resistance, and oxidation behavior of ceramics under extreme conditions.
Ceramic composites
In addition to PDCs, Riedel has contributed to the field of ceramic composites, where he has developed lightweight, high-strength materials by integrating ceramic matrices with other reinforcing materials. These composites are used in applications requiring exceptional mechanical properties, such as turbine blades and wear-resistant components.
Sustainability and green technologies
In recent years, Riedel has focused on using sustainable materials and processes in ceramics manufacturing, contributing to the development of environmentally friendly materials for energy-efficient systems.
Collaboration with industry
Throughout his career, Riedel has worked closely with industrial partners to ensure the translation of his research into practical applications. He has collaborated with companies in sectors such aerospace, automotive and energy
Awards and honors
1999: Dionyz-Stur-Gold Medal for Merits in Natural Science, Slovak Academy of Science, Bratislava, Slovak Republic
2000: Fellow of "The American Ceramic Society" (USA)
2006: Honorary Doctor (Dr. h. c.) of the Slovak Academy of Sciences, Bratislava, Slovak Republic
2009: Honorary Professor (Prof. h. c.) of the Tianjin University, Tianjin, P.R. China
2012: Tammann-Gedenkmünze of the Deutschen Gesellschaft für Materialkunde
2013: Fellow of the European Ceramic Society
2014: Fellow of the School of Engineering at The University of Tokyo, Japan
2020: International Ceramics Prize 2020 for "Basic Science" of the World Academy of Ceramics
2021: Honorary Professor (Prof. h. c.) of the Xiamen University, Xiamen, P.R. China
2023: Elected Member of the International Institute for the Science of Sintering
Editorial activities
Since 2016: Editor-in-Chief of the Journal “Ceramics International”
Since 2016: Member of the Editorial Board of the Journal of Ceramic Science and Technology
April 2018 – December 2027: Editor in Chief, Journal of the American Ceramic Society
2023-2025: Associate Editor Nature Portfolio Journal Advanced Manufacturing
Selected Publications
1. Li Lu, Tonghui Wen, Wei Li, Qingbo Wen, Zhaoju Yu, Shasha Tao, Jincan Yang, Yalei Wang, Xingang Luan, Xiang Xiong, Ralf Riedel, Single-source-precursor synthesis of dense monolithic SiC/(Ti0.25Zr0.25Hf0.25Ta0.25)C ceramic nanocomposite with excellent high-temperature oxidation resistance, J. Eur. Ceram. Soc. 44 (2024) 556-609.
2. Honghong Tian, Magdalena Graczyk-Zajac, Alois Kessler, Anke Weidenkaff, Ralf Riedel, Recycling and Reusing of Graphite from Retired Lithium-ion Batteries: A Review, Adv. Mater. 2023, 2308494
3. Liu, Jiongjie; Dong, Changyu; Lu, Xuefeng; Qiao, Zhuhui; Zhou, Feng; Liu, Weimin; Riedel, Ralf, Sn-containing Si3N4-based composites for adaptive excellent friction and wear in a wide temperature range, Journal of the European Ceramic Society, 42 (2022), 913-920.
4. Shrikant Bhat, Leonore Wiehl, Shariq Haseen, Peter Kroll, Konstantin Glazyrin, Philipp Gollé Leidreiter, Ute Kolb, Robert Farla, Jo-Chi Tseng, Emanuel Ionescu, Tomoo Katsura, and Ralf Riedel, A Novel High-Pressure Tin Oxynitride Sn2N2O, Chem. Eur. J. 0.1002/chem. 201904529.
5. Takashi Taniguchi, Dmytro Dzivenko, Ralf Riedel, Thierry Chauyeau, Andreas Zerr, Synthesis of cubic zirconium (IV) nitride, c-Zr3N4, in the 6-8 GPa pressure region, Ceramics international 45 (2019) 20028-20032.
6. Reinold, L.M.; Yamada, Y.; Graczyk-Zajac, M.; Munakata, H.; Kanamura, K.; Riedel, R.; "The influence of the pyrolysis temperature on the electrochemical behavior of carbon-rich SiCN polymer-derived ceramics as anode materials in lithium-ion batteries", J. Power Sources 282 (2015) 409-415.
7. Maged F. Bekheet, Marcus Schwarz, Stefan Lauterbach, Hans-Joachim Kleebe, Peter Kroll, Ralf Riedel, Aleksander Gurlo, "Orthorhombic In2O3: A metastable polymorph of indium sesquioxide", Angew. Chem. Int. Ed. 52 (2013) 6531-6535.
8. S. Sen, S. J. Widgeon, A. Navrotsky, G. Mera, A. Tavakoli, E. Ionescu, R. Riedel, "Can carbon substitute for oxygen in silicates in planetary interiors?", Proceedings of the National Academy of Sciences (PNAS) 110 (2013) 15904 – 15907.
9. E. Horvath-Bordon, R. Riedel, P. F. McMillan, P. Kroll, G. Miehe, P.A. van Aken, A. Zerr, P. Hoppe, O. Shebanova, I. McLaren, S. Lauterbach, E. Kroke, R. Boehler, High-pressure synthesis of crystalline carbon nitride imide, C2N2(NH). Angew. Chem. Int. Ed. 46 (2007) 1476.
10. A. Zerr, G. Miehe, G. Serghiou, M. Schwarz, E. Kroke, R. Riedel, H. Fueß, P. Kroll, R. Boehler, Synthesis of cubic silicon nitride. Nature 400 (1999) 340.
References
1956 births
Living people
German materials scientists
Inorganic chemists
20th-century German chemists
Scientific journal editors
University of Stuttgart alumni
Academic staff of Technische Universität Darmstadt | Ralf Riedel | [
"Chemistry"
] | 1,861 | [
"Inorganic chemists"
] |
78,808,726 | https://en.wikipedia.org/wiki/Audience%20capture | Audience capture is the phenomenon where an influencer is affected by their audience, catering to it with what they believe it wants to hear. This creates a positive feedback loop, which can lead the influencer to express more extreme views and behaviors.
An famous example of audience capture can be found in the story of the online influencer Nicholas Perry, known as Nikocado Avocado. Perry started off on YouTube with videos of himself playing the violin and supporting veganism. He then shifted to videos of himself eating known as mukbang. Audience capture led him to more and more extreme eating leading him in turn to obesity and poor health.
The term was coined by Eric Weinstein in 2018.
See also
Michelangelo phenomenon
Panopticon
Political base
References
External links
The Surprising Psychology of Audience Capture, Matt Johnson, NeuroscienceOf.com
Resisting Audience Capture: How to Maintain Integrity & Sanity Online, Matt Klein, ZINE Substack
The Perils of Audience Capture, The Prism by Gurwinder
Social media
Influence of mass media
Social influence | Audience capture | [
"Technology"
] | 209 | [
"Computing and society",
"Social media"
] |
78,809,060 | https://en.wikipedia.org/wiki/Liang%20%28mass%29 | Liang (), or leung in Cantonese, also called "Chinese ounce" or "tael", is a traditional Chinese unit for weight measurement. It originated in China before being introduced to neighboring countries in East Asia.
Nowaday, the mass of 1 liang equals 50 grams in mainland China, 37.5 grams in Taiwan, Korea and Thailand,
37.799 grams in Hong Kong, Singapore and Malaysia,
and 100 grams in Vietnam.
Liang is mostly used in the traditional markets, and famous for measuring gold, silver and Chinese medicines.
China Mainland
Chinese mass units promulgated in 1915
On 7 January 1915, the Beiyang government promulgated a measurement law to use not only metric system as the standard but also a set of Chinese-style measures based directly on the Qing dynasty definitions ().
where liang is the base unit equal to 37.301 grams.
Mass units in the Republic of China since 1930
On 16 February 1929, the Nationalist government adopted and promulgated The Weights and Measures Act to adopt the metric system as the official standard and to limit the newer Chinese units of measurement to private sales and trade, effective on 1 January 1930. These newer "market" units are based on rounded metric numbers. And jin became the base unit.
where liang is equal to 1/16 of a jin, or 31.25 grams.
Mass units in the People's Republic of China since 1959
On June 25, 1959, the State Council of the People's Republic of China issued the "Order on the Unified Measurement System", retaining the market measure system, with the statement of "The market system originally stated that sixteen liangs are equal to one jin. Due to the trouble of conversion, it should be changed to ten liangs per jin. "
Legally, 1 jin equals 500 grams, and 10 liangs equals 1 jin (that is, 1 liang equals 50 grams). The traditional Chinese medicine measurement system remains unchanged.
Taiwan
In 1895, Taiwan was ceded to Japan from China. The Japanese implemented the metric system, but the Taiwanese still followed their own habits and continued to use the old weights and measures of the Qing Dynasty. 1 Taiwan liang is equal to 37.5 grams, or 1/16 Taiwan jin.
where liang is the base unit.
Hong Kong and Macau
Hong Kong and Macau mass units
Currently, Hong Kong law stipulates that one liang is equal to 1/16 jin, which is 37.79936375 grams.
Similarly, Singapore law stipulates that one jin is also equal to sixteen liangs or 0.6048 kilograms, and one liang equals to 37.799 g. Malaysia has the same regulations as it is a former British colony.
Hong Kong troy units
These are used for trading precious metals such as gold and silver.
Korea
The base unit of Korean weight is the gwan. One liang (兩, Korean ounce) is 1/100 of a gwan, or 37.5 g (1.32 oz).
Vietnam
In Vietnam, the unit of liang is called "lang": 1 lang is equal to 37.8 grams by traditional value, and 100 grams by modern value.
For more information on the Chinese mass measurement system, please see article Jin (mass).
Compounds
wikt:幾斤幾兩 (jǐjīnjǐliǎng)
wikt:半斤八兩 (bànjīnbāliǎng)
wikt:缺斤少兩 (quējīnshǎoliǎng)
wikt:銀兩 (yínliǎng)
See also
Chinese units of measurement
Hong Kong units of measurement
Taiwanese units of measurement
Korean units of measurement
Vietnamese units of measurement
Notes
References
External links
中國度量衡#衡
市制
兩
Units of mass
Chinese units of measurement
Customary units of measurement | Liang (mass) | [
"Physics",
"Mathematics"
] | 757 | [
"Matter",
"Quantity",
"Units of mass",
"Mass",
"Customary units of measurement",
"Units of measurement"
] |
78,809,154 | https://en.wikipedia.org/wiki/Huawei%20Y6%20%282017%29 | The Huawei Y6 (2017) (stylized as HUAWEI Y6 2017 and also known as Huawei Nova Young) is an Android smartphone from the Y series manufactured and developed by Huawei. In China, it was announced and released under the name Honor 6 Play developed by Honor - a subsidiary of Huawei.
As of January 2025 in the Philippines, the phone was prized at 8,788 pesos.
Specifications
Design
The screen is made of glass. The phone case is made of plastic.
Similar to the Huawei Y5 2017, there is a microUSB port, a speaker, and a microphone styled to look like a speaker. At the top, there is a 3.5mm audio jack. On the right side, there are volume control buttons and the power button. A second microphone is located on the back panel. Slots for 2 SIM cards and a microSD memory card, which is expandable are located under the removable back panel.
The Huawei Y6 (2017) is available at 3 colors: White, Gold and Gray, while the Honor 6 Play is only available at 2 colors: White and Gold.
Processor
The Huawei Y6 2017 is powered by a MediaTek MT6737T processor, a quad-core 1.4 GHz. It has 4 Cortex-A53 cores clocked at 1.4 GHz. The graphics processor is Mali-T720MP2.
Display
The Huawei Y6 2017 features a 5.0-inch HD glass display with a resolution of 720 x 1280 pixels. It has an aspect ratio of 16:9.
Internal memory
The internal memory is 16 GB, while the RAM is 2 GB with the possibility of expansion using a microSD memory card up to 128 MB.
Camera
It has a 13 MP main camera with a dual flash and a 5 MP front camera.
Battery
The phone's battery capacity is 3000 mAh.
Software
The Huawei Y6 2017 runs on the Android 6.0 (Marshmallow) operating system with the EMUI 4.1 user interface.
The Y6 (2017) supports communication standards: GSM, HSPA and LTE.
The Y6 (2017) supports wireless interfaces: Wi-Fi 802.11 b/g/n, hotspot, Bluetooth 4.0, A2DP, LE. The smartphone supports the following navigation systems: GPS, A-GPS, GLONASS. It also has an FM radio.
References
Mobile phones introduced in 2017
Android (operating system) devices
Y6 2017 | Huawei Y6 (2017) | [
"Technology"
] | 517 | [
"Mobile technology stubs",
"Mobile phone stubs"
] |
78,809,630 | https://en.wikipedia.org/wiki/Mongol%20Refinery | The Mongol Refinery () is an oil refinery under construction in Altanshiree, Dornogovi Province, Mongolia.
History
The feasibility study to establish the refinery was approved by the Ministry of Mining and Heavy Industry on 15 November 2018. In October 2020, the engineering, procurement, and construction contract was signed with JMC Projects India. In January 2021, the groundbreaking work was held. The refinery is planned to be commissioned in 2026.
Architecture
The refinery will consist of three modules, which are EPC 2, EPC 3 and EPC 4. EPC 2 will consist of an integrated crude distillation unit, vacuum distillation unit and saturated gas plant. EPC 3 will consist of captive power plant. EPC 4 will consist of various units, plant buildings, satellite rack rooms and substation.
Technical specifications
Once completed, the refinery will have an annual petroleum processing capacity of 1.5 million tons. The refinery will be connected to two oil wells of Toson Uul XIX and Tamsag XXI by a 530-km underground pipeline.
Finance
The refinery will cost around US$1.698 billion. The funds will be provided by the Exim Bank of India under loan agreement with a total repayment period of 20 years and 1.75% annual interest rate.
See also
List of oil refineries
Mining in Mongolia
References
Altanshiree
Buildings and structures in Dornogovi Province
Buildings and structures under construction in Mongolia
Industrial buildings in Mongolia
Oil refineries | Mongol Refinery | [
"Chemistry"
] | 305 | [
"Petroleum",
"Oil refineries",
"Oil refining"
] |
78,810,231 | https://en.wikipedia.org/wiki/V553%20Centauri | V553 Centauri is a variable star in the southern constellation of Centaurus, abbreviated V553 Cen. It ranges in brightness from an apparent visual magnitude of 8.22 down to 8.80 with a period of 2.06 days. At that magnitude, it is too dim to be visible to the naked eye. Based on parallax measurements, it is located at a distance of approximately 1,890 light years from the Sun.
Observations
The variability of this star was announced in 1936 by C. Hoffmeister. In 1957, he determined it to be a Delta Cepheid variable with a magnitude range of and a periodicity of . The observers M. W. Feast and G. H. Herbig noted a peculiar spectrum with strong absorption lines of the molecules CH and CN, while neutral iron lines are unusually weak. They found a stellar classification of G5p I–III.
In 1972, T. Lloyd-Evans and associates found the star's prominent bands of C2, CH, and CN varied with the Cepheid phase, being strongest at minimum. They suggested a large overabundance of carbon in the star's atmosphere. Chemical analysis of the atmosphere in 1979 showed a metallicity close to solar, with an enhancement of carbon and nitrogen. It was proposed that V553 Cen is an evolved RR Lyrae variable and is now positioned above the horizontal branch on the HR diagram. V553 Cen is classified as a BL Herculis variable, being a low–mass type II Cepheid with a period between . As with other variables of this type, it displays a secondary bump on its light curve. It is a member of a small group of carbon Cepheids, and is one of the brightest stars of that type.
V553 Cen does not appear to have a companion. From the luminosity and shape of the light curve, stellar models from 1981 suggest a mass equal to 49% of the Sun's with 9.9 times the radius of the Sun. Further analysis of the spectrum showed that oxygen is not enhanced, but sodium may be moderately enhanced. There is no evidence of s-process enhancement of elements. Instead, the abundance peculiarities are the result of nuclear reaction sequences followed by dredge-up. In particular, these are the product of triple-α, CN, ON, and perhaps some Ne–Na reactions.
See also
Carbon star
RT Trianguli Australis
References
Further reading
BL Herculis variables
G-type giants
Centaurus
CD−31 11449
129981
072257
Centauri, V553 | V553 Centauri | [
"Astronomy"
] | 544 | [
"Centaurus",
"Constellations"
] |
78,810,986 | https://en.wikipedia.org/wiki/Tornado%20damage%20survey | A tornado damage survey, also known as a storm damage assessment, is a type of land survey that is conducted to determine the damage caused by tornadoes, and to give them ratings on the Enhanced Fujita scale. Damage surveys have been used since the 18th century to determine tornado-caused damage, and have become increasingly common following the implementation of the Fujita scale in 1971.
History
Although it is unknown when damage surveys began to be used to determine structural and property damage, one of the earliest known surveys was conducted by German scientist Gottlob Burchard Genzmer in the aftermath of the 1764 Woldegk tornado. Genzmer published a detailed survey of the damage path from the tornado, which documented the 33 km (18.6 mi) long track. The study, known as the "Genzmer Report", was the first to be conducted on a single tornado.
Damage surveys would become more common in the 1960s and 1970s, when Ted Fujita pioneered the Fujita scale, used to determine the strength of tornadoes. Fujita himself had surveyed damage after the atomic bombing of Nagasaki to determine where the bomb had exploded from. Following the Fargo tornado in 1957, Fujita conducted one of the first damage surveys using photographic evidence and ground measurements, using 200 photos to determine the approximate track of the tornado. Following the implementation of the Fujita Scale in 1971, hundreds of post-event damage surveys have been conducted on tornadoes and other weather events to determine the rating of the tornado. In the 2020s, drones have been used to survey hard-to-access areas, most notably following the 2021 Western Kentucky tornado.
Technology
Damage Assessment Toolkit
Since 2009, the Damage Assessment Toolkit (DAT), used by the National Weather Service, has been used to publish the preliminary results of damage surveys. An estimated 38,000 individual damage points have been recorded using the software.
See also
List of case studies on tornadoes (2020–present)
References
Surveying
Tornadoes
1971 in science | Tornado damage survey | [
"Engineering"
] | 398 | [
"Surveying",
"Civil engineering"
] |
78,811,704 | https://en.wikipedia.org/wiki/Wafer%20fabrication%20equipment | Wafer fabrication equipment is equipment that is used in the process of semiconductor fabrication to process raw semiconductor wafers into finished chips, such as integrated circuits.
Wafer fabrication equipment is meant to be installed in cleanrooms.
Types
Stepper
Burn-in oven
Market
Referred to respectively as the wafer fab equipment or wafer front end (equipment) market, both using the acronym WFE, the market is that of the manufacturers of the machines which in turn manufacture semiconductors. The apexresearch link in 2020 identified Applied Materials, ASML, KLA-Tencor, Lam Research, TEL and Dainippon Screen Manufacturing as market participants while the 2019 electronicsweekly.com report, citing The Information Network's president Robert Castellano, focused on the respective market shares commanded by the two leaders, Applied Materials and ASML.
See also
LCD manufacturing
FOUP
References
Semiconductor fabrication equipment
Semiconductor device fabrication | Wafer fabrication equipment | [
"Materials_science",
"Engineering"
] | 186 | [
"Semiconductor device fabrication",
"Semiconductor fabrication equipment",
"Microtechnology"
] |
78,812,860 | https://en.wikipedia.org/wiki/NGC%201536 | NGC 1536 is a peculiar barred spiral galaxy located around 57 million light-years away in the constellation Reticulum. It was discovered on December 4th, 1834 by the English astronomer John Herschel, and it has a diameter around 42,000 light-years. NGC 1536 is not known to have much star-formation, and it is not known to have an active galactic nucleus.
SN 1997D
SN 1997D is a Type II Supernova in NGC 1536 discovered by Duília de Mello in 1997. SN 1997D had a low expansion velocity, and it is believed that the explosion produced a stellar mass black hole, instead of a neutron star. SN 1997D was located in the southernmost part of NGC 1536.
Gallery
References
External links
https://ui.adsabs.harvard.edu/abs/1998ApJ...498L.129T/abstract
https://iopscience.iop.org/article/10.1086/311324/fulltext/
Barred spiral galaxies
Reticulum
1536 | NGC 1536 | [
"Astronomy"
] | 223 | [
"Reticulum",
"Constellations"
] |
78,812,891 | https://en.wikipedia.org/wiki/Constantia%20Alexandrou | Constantia Alexandrou () is a Cypriot physicist whose research focuses on lattice QCD, including the use of lattice QCD to elucidate the proton spin crisis. She is a professor at the University of Cyprus and at The Cyprus Institute.
Education and career
Alexandrou read physics at the University of Oxford, receiving a bachelor's degree there with first class honours in 1980. She continued her studies in the US at the Massachusetts Institute of Technology, where she completed her Ph.D. in 1985. Her dissertation was Stochastic study of one-dimensional many-fermion systems.
After postdoctoral research at the Paul Scherrer Institute in Switzerland and Erlangen University in Germany, she became an assistant professor at the University of Cyprus in 1993. She was promoted to associate professor in 1996 and full professor in 2003. She was the founding head of the Department of Physics of The Cyprus Institute, and since 2010 she has held a second affiliation as Institute Professor at the Computation-based Science and Technology Research Center there.
In 2022 she was elected for a two-year term as chair of PRACE, the Partnership for Advanced Computing in Europe.
Recognition
In 2019, Alexandrou received the International Fellow Award of the Helmholtz Association, funding a research visit to DESY in Germany. She was elected as a Fellow of the American Physical Society in 2024, after a nomination from the APS Division of Nuclear Physics, "for the pioneering contributions in calculating nucleon structure observables using lattice QCD".
References
External links
Year of birth missing (living people)
Living people
Cypriot scientists
Cypriot women academics
Particle physicists
Women physicists
Alumni of the University of Oxford
Massachusetts Institute of Technology alumni
Academic staff of the University of Cyprus
Fellows of the American Physical Society | Constantia Alexandrou | [
"Physics"
] | 361 | [
"Particle physicists",
"Particle physics"
] |
71,440,410 | https://en.wikipedia.org/wiki/Cladostephus | Cladostephus is a genus of marine brown alga.
References
Brown algae
Brown algae genera | Cladostephus | [
"Biology"
] | 21 | [
"Algae",
"Brown algae"
] |
71,440,611 | https://en.wikipedia.org/wiki/Leucocoprinus%20zeylanicus | Leucocoprinus zeylanicus is a species of mushroom producing fungus in the family Agaricaceae.
Taxonomy
It was first described in 1847 by the British mycologist Miles Joseph Berkeley who classified it as Agaricus zeylanicus.
In 1891 it was classified as Mastocephalus zeylanicus by the German botanist Otto Kunze, however Kunze's Mastocephalus genus, along with most of 'Revisio generum plantarum was not widely accepted by the scientific community of the age so it remained an Agaricus.
In 1940 it was reclassified as Leucocoprinus zeylanicus by the Dutch mycologist Karel Bernard Boedijn.
Description
Leucocoprinus zeylanicus is a small dapperling mushroom. Cap: Around 8cm wide. Campanulate (bell shaped) with an umbo in the centre and striations at the edges. Gills: Free. Stem: Smooth with a narrow stem ring. Spores:''' 7.5-9x4.5-6.5 μm.
Habitat and distribution L. zeylanicus'' is scarcely recorded and little known however it is reported to be a very common species in the Western Ghats ranges of India. In 2003 a mushroom survey conducted at the Tropical Botanic Garden and Research Institute, in Kerala state, India observed this species growing on the campus. It was found scattered or in groups on the forest floor and in flower beds in the garden which had been well fertilised with manure as well as on cow dung itself and occasionally on the bark of living trees.
Berkeley described the mushroom from a garden in Peradeniya, Sri Lanka (then known as Ceylon) in 1844. Many of his observations were conducted in this area so it is possible that they were in or around the vicinity of the Royal Botanical Gardens, Peradeniya, which were founded in 1843.
References
Leucocoprinus
Fungi described in 1847
Taxa named by Miles Joseph Berkeley
Fungus species | Leucocoprinus zeylanicus | [
"Biology"
] | 421 | [
"Fungi",
"Fungus species"
] |
71,441,316 | https://en.wikipedia.org/wiki/Bebras%20Competition | The International Bebras Challenge on Informatics is an annual computer science competition for primary and secondary school students around the world. With 87 member countries and more than 2.5 million participating students in 2024, the competition is the largest computer science competition in the world. The Bebras competition adds new countries every year.
Format
The Bebras is a 45-minute multiple-choice test with 15 problems. The problems are divided into three pairs of 5, and classified as "easy", "medium" and "hard". In most countries, the competition is administered through a web system that automatically scores each participant's work. The pool of Bebras problems is agreed upon during the annual international "Bebras Task Workshop" by the representatives of all member countries.
History
Originally founded by the University of Vilnius and first administered in Lithuania in 2004, the Bebras competition is named after Lithuanian word "Bebras" which translates to "beaver". The competition has been subject of research and several dozen publications.
In 2015, the Bebras organization was awarded the Microsoft-sponsored "Best Practices in Education Award" by Informatics Europe. In 2019 Google awarded Bebras Indonesia a $1 million grant to support the program and further train teachers in the field of computer science.
By 2022, there were two and a half million global participants.
Bebras in the United Kingdom
The "Bebras Computing Challenge" is organized by the University of Oxford and backed by the Raspberry Pi Foundation in the United Kingdom and has more than 300,000 annual participants. Students with a score in the top 10% of their relative age group are invited to sit the Oxford University Computing Challenge.
Members
As of 2024, there are 60 full members and 27 provisional members.
Full members
(suspended in April 2022)
(suspended in April 2022)
Provisional members
References
External links
Bebras International Challenge on Informatics and Computational Thinking
2004 establishments in Lithuania
Recurring events established in 2004
Computer science competitions
Computer science education
Awards and prizes of the University of Oxford
Vilnius University | Bebras Competition | [
"Technology"
] | 420 | [
"Computer science education",
"Computer science"
] |
71,443,545 | https://en.wikipedia.org/wiki/ISAM-140 | ISAM-140 is a selective non-xanthinic adenosine A2B receptor antagonist. Discovered in 2016, it has a Ki of 3.49 nM on the A2B receptor and >1000-fold selectivity with respect to the other three adenosine receptor subtypes. It has been shown to help the immune system to attack cancer cells in in vitro assays by rescuing T and NK cell proliferation, cytokine release, and TIL infiltration.
References
2-Furyl compounds
Esters
Nitrogen heterocycles
Heterocyclic compounds with 3 rings | ISAM-140 | [
"Chemistry"
] | 120 | [
"Organic compounds",
"Esters",
"Functional groups"
] |
71,444,220 | https://en.wikipedia.org/wiki/Plasticolous%20lichen | A plasticolous lichenized fungi is a lichen which grows on plastic surfaces. This behaviour was first observed in 1994 when foliicolous lichens were found growing on plastic tape but they have since been observed growing on artificial plastic leaves, plastic signs and nylon nets.
References
Lichenology | Plasticolous lichen | [
"Biology"
] | 63 | [
"Lichenology"
] |
71,446,775 | https://en.wikipedia.org/wiki/Time%20in%20Senegal | Time in Senegal is given by a single time zone, denoted as Greenwich Mean Time (GMT; UTC+00:00). Senegal shares this time zone with several other countries, including fourteen in western Africa. Senegal does not observe daylight saving time (DST).
History
Senegal first adopted UTC−01:00 on 1 January 1912.
IANA time zone database
In the IANA time zone database, Senegal is given one zone in the file zone.tab – Africa/Dakar. "SN" refers to the country's ISO 3166-1 alpha-2 country code. Data for Senegal directly from zone.tab of the IANA time zone database; columns marked with * are the columns from zone.tab itself:
See also
Time in Africa
List of time zones by country
References
External links
Current time in Senegal at Time.is
Time in Senegal at TimeAndDate.com
Time by country
Geography of Senegal
Time in Africa | Time in Senegal | [
"Physics"
] | 191 | [
"Spacetime",
"Physical quantities",
"Time",
"Time by country"
] |
71,449,047 | https://en.wikipedia.org/wiki/SZ%20Lyncis | SZ Lyncis is a binary star system in the northern constellation of Lynx, abbreviated SZ Lyn. It is a variable star with an apparent visual magnitude that fluctuates around 9.58, which is too faint to be visible to the naked eye. The distance to this system is approximately 1,700 light years based on parallax measurements, and it is drifting further away with a radial velocity of 34 km/s.
The variability of this system was announced in 1949 by C. Hoffmeister. V. Zessewitch
generated a light curve from photographic observations, showing a period of 0.25 days. H. Schneller in 1961 classified it as a short-period RR Lyrae variable. O. J. Eggen in 1962 found a period of 0.12 days, or half that of earlier measurements. P. Broglia in 1963 noted that the ~0.5 magnitude amplitude variation of SZ Lyn is more consistent with a dwarf Cepheid of the AI Velorum type (later termed a Delta Scuti variable).
Comparison of the times of maximum light by A. M. van Genderen in 1967 showed a variation in the period. This followed a sine wave with a period of 1,129 days. In 1975, T. G. Barnes and T. J. Moffett confirmed the period variation and suggested it is being caused by a light-travel time effect in a single-lined spectroscopic binary with an orbital period of 3.14 years. Radial velocity measurements by C. Bardin and M. Imbert in 1984 confirmed the binary nature of this system. Updated orbital elements were published by T. J. Moffett and associates in 1988.
This is a spectroscopic binary system with an orbital period of and an eccentricity (ovalness) of 0.19. A decrease in the longitude of the periapsis has been detected, which may indicate that the secondary component is actually a close binary. The primary component is a Delta Scuti variable with a main pulsation frequency of 8.296943 cycles per day. 23 frequencies have been identified, of which 14 are multiples of the main frequency. Models of the stellar properties suggest that it is near the end of its core hydrogen burning stage, or has just begun shell burning. The secondary is likely a main sequence star with a class in the range .
References
Further reading
F-type main-sequence stars
F-type subgiants
Delta Scuti variables
Spectroscopic binaries
Lynx (constellation)
Durchmusterung objects
067390
039960
Lyncis, SZ | SZ Lyncis | [
"Astronomy"
] | 541 | [
"Lynx (constellation)",
"Constellations"
] |
71,449,362 | https://en.wikipedia.org/wiki/Lennox%20Merit%20Series%20air%20conditioner | Lennox Merit series is a line of residential air conditioners made by Lennox International. The Merit series is considered the budget series in the three tiers of Lennox air conditioner models. The series is manufactured in Saltillo, Mexico.
History
Lennox has three different series of air conditioners, Elite, Dave Lennox Signature Collection and Merit series. The Merit series is the lowest cost Lennox air conditioner, and there are 4 models of Single-stage with a 13, 14, 15 or 16 Seasonal energy efficiency ratio (SEER) rating. The units are also available with ratings from 1.4 tons to 5 tons. The company offers a warranty of up to ten years
The Merit series is manufactured in Saltillo, Mexico, under the name LII United Products. The Merit series is the primary Lennox-brand product serving Sun Belt market. The Saltillo location allowed Lennox to serve the Sun Belt with lower cost of shipping the units. The 300,000 sqft plant began in 2007 with an expected full production date of 2010. The Merit air conditioner line was the only Merit series product which was produced in Mexico.
Reception
Lennox air conditioners are known for energy efficiency, however they are louder than other brands of air conditioners: the industry average of 40 to 60 decibels, and Lennox machines are 70 decibels. Even though the Merit series is considered the budget line of Lennox air conditioners, it is still more expensive than most comparable models on the market. All Lennox models including the Merit series are known for being higher priced but efficient and reliable. In 2022 Consumer Reports survey of members gave Lennox air conditioning units a top rating of Excellent.
References
Cooling technology
Home appliances
Goods manufactured in Mexico | Lennox Merit Series air conditioner | [
"Physics",
"Technology"
] | 344 | [
"Physical systems",
"Machines",
"Home appliances"
] |
74,438,910 | https://en.wikipedia.org/wiki/Jason%20Micklefield | Jason Micklefield is a British Biochemist and a professor in the Department of Chemistry at The University of Manchester. His research involves the discovery, characterisation and engineering of biosynthetic pathways to new bioactive natural products, particularly antibiotics. He is also interested in the discovery, structure, mechanism and engineering of enzymes for synthetic applications, including the integration of enzymes with chemocatalysis for telescoping routes to pharmaceuticals and other valuable products.
Education
Micklefield attended Royds Comprehensive School in Leeds. He received his BSc. Degree in Chemistry from Hull University in 1989 and earned a Ph.D. from the University of Cambridge in 1993 working with Professor Sir Alan Battersby to complete the first total synthesis of haem d1, a coenzyme in bacteria.
Career and research
Following his PhD, Micklefield was awarded a NATO fellowship to work on enzyme mechanisms and biosynthesis with Professor Heinz G. Floss at the University of Washington, Seattle USA. In 1995, Micklefield was appointed Lecturer in Organic Chemistry at Birkbeck College, University of London, before moving to Manchester in 1998. He was promoted to Professor of Chemical Biology at the University of Manchester in 2008 where his research group is based in the Manchester Institute of Biotechnology (MIB). Micklefield is also visiting professor at the East China University of Science and Technology (ECUST) in Shanghai. He is co-director of the EPSRC Centre for Doctoral Training in Integrated Catalysis (iCAT) and served as Director of the BBSRC Natural Product Discovery and Bioengineering Network (NPRONET). Micklefield was the recipient of the RSC Interdisciplinary Prize (2022), Bader Award (2019), Natural Product Reports (NPR) Lecture Award (2008). He also received a European Research Council (ERC) Advanced grant and his lab also won the RSC Horizon Prize & Rita and John Cornforth Award (2023).
Micklefield's research focuses on natural product biosynthesis, pathway engineering and biocatalysis. His lab developed new methods for engineering complex NRPS enzymes that deliver new lipopeptide antibiotics. They have discovered and characterised hybrid NRPS-PKS assembly lines producing the structurally unique antibiotic K16. Micklefield's team also discovered and determined structures of novel ATP-dependent ligase enzymes, from PKS-NRPS pathways, which were engineered to produce agrochemicals and pharmaceuticals including drugs in clinical trials for COVID-19. New synthetic biology approaches were also used to create a de novo pathway to thaxtomin phytotoxin derivatives, with improved herbicidal properties for crop protection. In addition to biosynthesis, Micklefield is widely recognised for his research in biocatalysis. His lab employed structure-guided mutagenesis and directed evolution to improve activity, expand the substrate scope and switch the regioselectivities of halogenase enzymes. They showed how engineered halogenases can be integrated with Pd-catalysed cross-coupling chemistry, in one-pot reactions, to affect the direct regioselective arylation, alkenylation, cyanation and further functionalisation of C-H positions in diverse scaffolds. Micklefield's lab also characterised various methyltransferases, demonstrating how these can be used in the regioselective alkyl-diversification of tetrahydroisoquinolines, rapamycin immunosuppressive agents and other bioactive natural and non-natural products. His lab succeeded in engineering orthogonal methyltransferases creating alternative bioalkylation pathways and developed methods for selective derivatisation of tyrosine residues in peptides/proteins using methyltransferases and SAM analogues for labelling etc. His team also characterised, engineered and developed many other important biocatalysts. The Micklefield lab is also engaged in nucleic acids research, re-engineering the first orthogonal riboswitches (genetic tools and biosensors).
Awards and honours
Royal Society of Chemistry, Chemistry Biology Interface Horizon Prize: Rita and John Cornforth Award (2023) Also see RSC Video: Horizon Prize 2023
Royal Society of Chemistry, Interdisciplinary Prize (2022)
Royal Society of Chemistry, Bader Award (2019)
References
British biochemists
Academics of the University of Manchester
Alumni of the University of Cambridge
Alumni of the University of Hull
British organic chemists
Structural biologists
Living people
Year of birth missing (living people) | Jason Micklefield | [
"Chemistry"
] | 933 | [
"British organic chemists",
"Organic chemists",
"Structural biologists",
"Structural biology"
] |
74,439,183 | https://en.wikipedia.org/wiki/Human%20climate%20niche | The human climate niche is the ensemble of climate conditions that have sustained human life and human activities, like agriculture, on the globe for the last millennia. The human climate niche is estimated by calculating the human population density with respect to mean annual temperature. The human population distribution as a function of mean annual temperature is bimodal and results in two modes; one at 15 °C and another one at ~20 to 25 °C. Crops and livestock required for sustaining the human population are also limited to the similar niche conditions. Given the rise in mean global temperatures, the human population is projected to experience climate conditions beyond the human climate niche. Some projections show that considering temperature and demographic changes, 2.0 and 3.7 billion people will live in out of the niche by 2030 and 2090, respectively.
References
Human biology
Human ecology
Climate change adaptation | Human climate niche | [
"Biology",
"Environmental_science"
] | 170 | [
"Human ecology",
"Environmental social science",
"Human biology"
] |
74,439,886 | https://en.wikipedia.org/wiki/Theranostics | Theranostics, also known as theragnostics, is a technique commonly used in personalised medicine. For example in nuclear medicine, one radioactive drug is used to identify (diagnose) and a second radioactive drug is used to treat (therapy) cancerous tumors. In other words, theranostics combines radionuclide imaging and radiation therapy which targets specific biological pathways.
Technologies used for theranostic imaging include radiotracers, contrast agents, positron emission tomography, and magnetic resonance imaging. It has been used to treat thyroid cancer and neuroblastomas.
The term "theranostic" is a portmanteau of two words, therapeutic and diagnostic, thus referring to a combination of diagnosis and treatment that also allows for continuing medical assessment of a patient. The first known use of the term is attributed to John Funkhouser, a consultant for the company Cardiovascular Diagnostic, who used it in a press release in August 1998.
Applications
Nuclear medicine
Theranostics originated in the field of nuclear medicine; iodine isotope 131 for the diagnostic study and treatment of thyroid cancer was one of its earliest applications. Nuclear medicine encompasses various substances, either alone or in combination, that can be used for diagnostic imaging and targeted therapy. These substances may include ligands of receptors present on the target tissue or compounds, like iodine, that are internalized by the target through metabolic processes. By using these mechanisms, theranostics enables the localization of pathological tissues with imaging and the targeted destruction of these tissues using high doses of radiation.
Radiological scope
Contrast agents with therapeutic properties have been under development for several years. One example is the design of contrast agents capable of releasing a chemotherapeutic agent locally at the target site, triggered by a stimulus provided by the operator. This localized approach aims to increase treatment efficacy and minimize side effects. For instance, ultrasound-based contrast media, such as microbubbles, can accumulate in hypervascularized tissues and release the active ingredient in response to ultrasound waves, thus targeting a specific area chosen by the sonographer.
Another approach involves linking monoclonal antibodies (capable of targeting different molecular targets) to nanoparticles. This strategy enhances the drug's affinity and specificity towards the target and enables visualization of the treatment area, such as using superparamagnetic iron oxide particles detectable by magnetic resonance imaging. Additionally, these particles can be designed to release chemotherapy agents specifically at the site of binding, producing a local synergistic effect with antibody action. Integrating these methods with medical-nuclear techniques, which offer greater imaging sensitivity, may aid in target identification and treatment monitoring.
Imaging techniques
Positron emission tomography
Positron emission tomography (PET) imaging in theranostics provides insight into metabolic and molecular processes within the body. The PET scanner detects photons and creates three-dimensional images that enable visualization and quantification of physiological and biochemical processes. PET imaging uses radiotracers that target specific molecules or processes. For example, [18F] fluorodeoxyglucose (FDG) is commonly used to assess glucose metabolism, as cancer cells exhibit increased glucose uptake. Other radiotracers target specific receptors, enzymes, or transporters, allowing the evaluation of various physiological and pathological processes.
PET imaging plays a role in both diagnosis and treatment planning. It aids in the identification and staging of diseases, such as cancer, by visualizing the extent and metabolic activity of tumors. PET scans can also guide treatment decisions by assessing treatment response and monitoring disease progression. Additionally, PET imaging is used to determine the suitability of patients for targeted therapies based on specific molecular characteristics, enabling personalized treatment approaches.
Single-photon emission computed tomography
Single-photon emission computed tomography (SPECT) is employed in theranostics, using gamma rays emitted by a radiotracer to generate three-dimensional images of the body. SPECT imaging involves the injection of a radiotracer that emits single photons, which are detected by a gamma camera rotating around the person undergoing imaging.
SPECT provides functional and anatomical information, allowing the assessment of organ structure, blood flow, and specific molecular targets. It is useful in evaluating diseases that involve altered blood flow or specific receptor expression. For example, SPECT imaging with technetium-99m (Tc-99m) radiopharmaceuticals may be able to assess myocardial perfusion and identify areas of ischemia or infarction in patients with cardiovascular diseases.
SPECT imaging helps in identifying disease localization, staging, and assessing the response to therapy. Moreover, SPECT imaging is employed in targeted radionuclide therapy, where the same radiotracer used for diagnostic imaging can be used to deliver therapeutic doses of radiation to the diseased tissue.
Magnetic resonance imaging
Magnetic resonance imaging (MRI) is a non-invasive imaging technique that uses strong magnetic fields and radiofrequency pulses to generate detailed anatomical and functional images of the body. MRI provides excellent soft tissue contrast and is widely used in theranostics for its ability to visualize anatomical structures and assess physiological processes.
In theranostics, MRI allows for the detection and characterization of tumors, assessment of tumor extent, and evaluation of treatment response. MRI can provide information on tissue perfusion, diffusion, and metabolism, aiding in the selection of appropriate therapies and monitoring their effectiveness.
Advancements in MRI technology have expanded its capabilities in theranostics. Techniques such as functional MRI (fMRI) enable the assessment of brain activation and connectivity, while diffusion-weighted imaging (DWI) provides insights into tissue microstructure. The development of molecular imaging agents, such as superparamagnetic iron oxide nanoparticles, allows for targeted imaging and tracking of specific molecular entities.
Therapeutic approaches
Theranostics encompasses a range of therapeutic approaches that are designed to target and treat diseases with enhanced precision.
Targeted drug delivery systems
Targeted drug delivery systems facilitate the selective delivery of therapeutic agents to specific disease sites while minimizing off-target effects. These systems employ strategies, such as nanoparticles, liposomes, and micelles, to encapsulate drugs and enhance their stability, solubility, and bioavailability. By incorporating diagnostic components, such as imaging agents or targeting ligands, into these delivery systems, clinicians can monitor drug distribution and accumulation in real-time, ensuring effective treatment and reducing systemic toxicity. Targeted drug delivery systems hold promise in the treatment of cancer, cardiovascular diseases, and other conditions, as they allow for personalized and site-specific therapy.
Gene therapy
Gene therapy is a therapeutic approach that involves modifying or replacing faulty genes to treat or prevent diseases. In theranostics, gene therapy can be combined with diagnostic imaging to monitor the delivery, expression, and activity of therapeutic genes. Imaging techniques such as MRI, PET, and optical imaging enable non-invasive assessment of gene transfer and expression, providing valuable insights into the efficacy and safety of gene-based treatments. Gene therapy has shown potential in treating genetic disorders, cancer, and cardiovascular diseases, and its integration with diagnostic imaging offers a comprehensive approach for monitoring and optimizing treatment outcomes.
Radiotherapy
Radiotherapy can be integrated with imaging techniques to guide treatment planning, monitor radiation dose distribution, and assess treatment response. Molecular imaging methods, such as PET and SPECT, can be employed to visualize and quantify tumor characteristics, such as hypoxia or receptor expression, aiding in personalized radiation dose optimization10.
Additionally, theranostic approaches involving radiolabeled therapeutic agents, known as radiotheranostics, combine the therapeutic effects of radiation with diagnostic capabilities. Radiotheranostics, including Peptide receptor radionuclide therapy (PRRT), hold promise for targeted radiotherapy, enabling precise tumor targeting and dose escalation, while sparing healthy tissues. For example, PRRT based on Lutetium-177 combinations (known as radioligands) has emerged as a treatment option for inoperable metastatic neuroendocrine tumours (NET).
Immunotherapy
Immunotherapy harnesses the body's immune system to recognize and attack cancer cells or other disease targets. In theranostics, immunotherapeutic approaches can be coupled with diagnostic imaging to assess immune cell infiltration, tumor immunogenicity, and treatment response. Imaging techniques, such as PET and MRI, can provide valuable information about the tumor microenvironment, immune cell dynamics, and response to immunotherapies. Furthermore, theranostic strategies involving the use of radiolabeled immunotherapeutic agents allow for simultaneous imaging and therapy, aiding in patient selection, treatment monitoring, and optimization of immunotherapeutic regimens.
Nanomedicine
Nanomedicine refers to the use of nanoscale materials for medical applications. In theranostics, nanomedicine offers opportunities for targeted drug delivery, imaging, and therapy. Nanoparticles can be engineered to carry therapeutic payloads, imaging agents, and targeting ligands, allowing for multimodal theranostic approaches. These nanocarriers can enhance drug stability, improve drug solubility, and enable controlled release at the disease site. Additionally, nanomaterials with inherent imaging properties, such as quantum dots or gold nanoparticles, can serve as contrast agents for imaging.
Applications and challenges
Oncology
Theranostics has been applied in oncology, contributing to new approaches in the diagnosis, treatment, and monitoring of cancers. By integrating diagnostic imaging and targeted therapies, theranostics offers personalized approaches that improve treatment outcomes and patient care. In oncology, theranostics encompasses a wide range of applications, including the management of various types of cancers such as breast, lung, prostate, and colorectal cancer. Molecular imaging techniques, such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT), enable the visualization and characterization of cancerous lesions, aiding in early detection, staging, and assessment of treatment response. This allows for more accurate and tailored treatment planning, including the selection of appropriate targeted therapies or the optimization of radiation therapy.
Despite the significant progress, the translation of theranostics into routine clinical practice faces challenges, including the need for standardized imaging protocols, biomarker validation, and regulatory considerations. Additionally, there is a continuous need for research and development to further enhance the effectiveness and accessibility of theranostic approaches in oncology.
Neurology and cardiology
Theranostics extends beyond oncology and holds potential in the fields of neurology and cardiology. In neurology, theranostic approaches offer new avenues for the diagnosis and treatment of various neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, and multiple sclerosis. Advanced imaging techniques, including magnetic resonance imaging (MRI) and positron emission tomography (PET), allow for the visualization of neuroanatomy, functional connectivity, and molecular changes in the brain. This enables early detection, precise diagnosis, and monitoring of disease progression, facilitating the development of targeted therapeutic interventions.
Similarly, in cardiology, theranostics play a significant role in the diagnosis and treatment of cardiovascular conditions. Non-invasive imaging modalities like MRI and computed tomography (CT) provide detailed information about cardiac structure, function, and blood flow, aiding in the assessment of heart disease and the guidance of interventions. Theranostic approaches in cardiology involve targeted drug delivery systems for the treatment of conditions such as atherosclerosis and restenosis, as well as image-guided interventions for precise stenting or catheter-based therapies.
Research directions
Several challenges remain to be addressed for widespread adoption and integration of theranostics into routine clinical practice. Regulatory considerations will play a role in ensuring the safety, efficacy, and quality of theranostic agents and technologies. Harmonization of regulations across different countries and regions is necessary to facilitate global implementation. Cost-effectiveness is a significant challenge, as theranostic approaches can be expensive. Strategies to optimize resource utilization and reimbursement models have been discussed. Technical limitations, such as the development of more specific and sensitive imaging agents, improvement of imaging resolution and quality, and the integration of different imaging modalities, require ongoing research and technological advancements. Ethical considerations surrounding patient privacy, data security, and the responsible use of patient information need to be addressed.
References
Medicinal radiochemistry
Diagnostic radiology
Radiation therapy procedures
Technology neologisms
1998 neologisms | Theranostics | [
"Chemistry"
] | 2,615 | [
"Medicinal radiochemistry",
"Medicinal chemistry"
] |
74,440,011 | https://en.wikipedia.org/wiki/Climate%20based%20daylight%20modelling | Climate based daylight modelling (CBDM) also known as dynamic daylight metrics is a calculation methodology first developed in the late 1990s to assess daylight quality and quantity. It is used by Building Design engineers and architects to predict luminance and/or illuminance within buildings using standardised sun and sky condition climate data for a given geographical location. It is a different design metric to Daylight factors which only considers the ratio of the light level inside a structure to the light level outside the structure from an overcast sky.
With CBDM, if used considerately, the facade design of a building can be optimised to maximise useful daylight whilst excluding excessive daylight, which otherwise might cause issues with glare, visual discomfort, and/or solar gains which can cause thermal comfort issues. At the same time reducing reliance and operation of artificial lighting.
CBDM calculations are calculated within Building simulation modelling software tools for each and every hour of the year, or sometimes for smaller increments, which allows for daily and seasonal profiles to be tested and optimised
The key metrics reported on within CBDM software are as follows:
'Daylight Autonomy' (DA), the amount of time that a point in a room can be expected to achieve a target level of illuminance from daylight. Normally expressed as a percentage for a useful level of illuminance to be met or exceeded, for example 300 lux
'Spatial Daylight Autonomy' (sDA); the amount of time that a point on the working plane in a room can be expected to achieve a target level of illuminance from daylight. The working plane is established to represent a useful working height within the space, such as at desk level. The sDA is normally expressed as a percentage target for a useful level of illuminance for a given target, for example; 50% of a 300 lux DA target on the working plane (300/50%)
'Useful Daylight Illuminance' (UDI-a); the summed annual occurrence of illuminance on the working plane and during the occupied hours for the space. Typically, the target may be between 100 and 3000 lux. Any hours of illuminance below 100 lux is defined as UDI-s, and typically would require artificial lighting to be switched on. Any hours of illuminance above 3000 lux is defined as UDI-e, and indicates excessive daylight which can cause visual discomfort and glare/contrast issues and typically would require blinds or curtains to be closed.
See also
Daylighting
Right to light
Daylight factor
Notes
External links
International Commission on Illumination
Light
Visibility
Energy-saving lighting
Lighting | Climate based daylight modelling | [
"Physics",
"Mathematics"
] | 536 | [
"Physical phenomena",
"Visibility",
"Spectrum (physical sciences)",
"Physical quantities",
"Quantity",
"Electromagnetic spectrum",
"Waves",
"Light",
"Wikipedia categories named after physical quantities"
] |
74,440,694 | https://en.wikipedia.org/wiki/ODE/IM%20correspondence | In mathematical physics, the ODE/IM correspondence is a link between ordinary differential equations (ODEs) and integrable models. It was first found in 1998 by Patrick Dorey and Roberto Tateo. In this original setting it relates the spectrum of a certain integrable model of magnetism known as the XXZ-model to solutions of the one-dimensional Schrödinger equation with a specific choice of potential, where the position coordinate is considered as a complex coordinate.
Since then, such a correspondence has been found for many more ODE/IM pairs.
See also
Bethe ansatz
WKB approximation
References
Integrable systems
Spin models
Ordinary differential equations | ODE/IM correspondence | [
"Physics"
] | 136 | [
"Spin models",
"Integrable systems",
"Theoretical physics",
"Quantum mechanics",
"Statistical mechanics"
] |
74,442,379 | https://en.wikipedia.org/wiki/Causal%20notation | Causal notation is notation used to express cause and effect.
In nature and human societies, many phenomena have causal relationships where one phenomenon A (a cause) impacts another phenomenon B (an effect). Establishing causal relationships is the aim of many scientific studies across fields ranging from biology and physics to social sciences and economics. It is also a subject of accident analysis, and can be considered a prerequisite for effective policy making.
To describe causal relationships between phenomena, non-quantitative visual notations are common, such as arrows, e.g. in the nitrogen cycle or many chemistry and mathematics textbooks. Mathematical conventions are also used, such as plotting an independent variable on a horizontal axis and a dependent variable on a vertical axis, or the notation to denote that a quantity "" is a dependent variable which is a function of an independent variable "". Causal relationships are also described using quantitative mathematical expressions. (See Notations section.)
The following examples illustrate various types of causal relationships. These are followed by different notations used to represent causal relationships.
Examples
What follows does not necessarily assume the convention whereby denotes an independent variable, and
denotes a function of the independent variable . Instead, and denote two quantities with an a priori unknown causal relationship, which can be related by a mathematical expression.
Ecosystem example: correlation without causation
Imagine the number of days of weather below one degrees Celsius, , causes ice to form on a lake, , and it causes bears to go into hibernation . Even though does not cause and vice-versa, one can write an equation relating and . This equation may be used to successfully calculate the number of hibernating bears , given the surface area of the lake covered by ice. However, melting the ice in a region of the lake by pouring salt onto it, will not cause bears to come out of hibernation. Nor will waking the bears by physically disturbing them cause the ice to melt. In this case the two quantities and are both caused by a confounding variable (the outdoor temperature), but not by each other. and are related by correlation without causation.
Physics example: a unidirectional causal relationship
Suppose an ideal solar-powered system is built such that if it is sunny and the sun provides an intensity of watts incident on a m solar panel for seconds, an electric motor raises a kg stone by meters, . More generally, we assume the system is described by the following expression:
,
where represents intensity of sunlight (Jsm), is the surface area of the solar panel (m), represents time (s), represents mass (kg), represents the acceleration due to Earth's gravity ( ms), and represents the height the rock is lifted (m).
In this example, the fact that it is sunny and there is a light intensity , causes the stone to rise , not the other way around; lifting the stone (increasing ) will not result in turning on the sun to illuminate the solar panel (an increase in ). The causal relationship between and is unidirectional.
Medicine example: two causes for a single outcome
Smoking, , and exposure to asbestos, , are both known causes of cancer, . One can write an equation to describe an equivalent carcinogenicity between how many cigarettes a person smokes, , and how many grams of asbestos a person inhales, . Here, neither causes nor causes , but they both have a common outcome.
Bartering example: a bidirectional causal relationship
Consider a barter-based economy where the number of cows one owns has value measured in a standard currency of chickens, . Additionally, the number of barrels of oil one owns has value which can be measured in chickens, . If a marketplace exists where cows can be traded for chickens which can in turn be traded for barrels of oil, one can write an equation to describe the value relationship between cows and barrels of oil . Suppose an individual in this economy always keeps half of their value in the form of cows and the other half in the form of barrels of oil. Then, increasing their number of cows by offering them 4 cows, will eventually lead to an increase in their number of barrels of oil , or vice-versa. In this case, the mathematical equality describes a bidirectional causal relationship.
Notations
Chemical reactions
In chemistry, many chemical reactions are reversible and described using equations which tend towards a dynamic chemical equilibrium. In these reactions, adding a reactant or a product causes the reaction to occur producing more product, or more reactant, respectively. It is standard to draw “harpoon-type” arrows in place of an equals sign, , to denote the reversible nature of the reaction and the dynamic causal relationship between reactants and products.
Statistics: Do notation
Do-calculus, and specifically the do operator, is used to describe causal relationships in the language of probability. A notation used in do-calculus is, for instance:
,
which can be read as: “the probability of given that you do ”. The expression above describes the case where is independent of anything done to . It specifies that there is no unidirectional causal relationship where causes .
Causal diagrams
A causal diagram consists of a set of nodes which may or may not be interlinked by arrows. Arrows between nodes denote causal relationships with the arrow pointing from the cause to the effect. There exist several forms of causal diagrams including Ishikawa diagrams, directed acyclic graphs, causal loop diagrams, and why-because graphs (WBGs). The image below shows a partial why-because graph used to analyze the capsizing of the Herald of Free Enterprise.
Junction patterns
Junction patterns can be used to describe the graph structure of Bayesian networks. Three possible patterns allowed in a 3-node directed acyclic graph (DAG) include:
Causal equality notation
Various forms of causal relationships exist. For instance, two quantities and can both be caused by a confounding variable , but not by each other. Imagine a garbage strike in a large city, , causes an increase in the smell of garbage, and an increase in the rat population . Even though does not cause and vice-versa, one can write an equation relating and . The following table contains notation representing a variety of ways that , and may be related to each other.
It should be assumed that a relationship between two equations with identical senses of causality (such as , and ) is one of pure correlation unless both expressions are proven to be bi-directional causal equalities. In that case, the overall causal relationship between and is bi-directionally causal.
References
Notation | Causal notation | [
"Mathematics"
] | 1,349 | [
"Symbols",
"Notation"
] |
74,443,495 | https://en.wikipedia.org/wiki/Progressive-iterative%20approximation%20method | In mathematics, the progressive-iterative approximation method is an iterative method of data fitting with geometric meanings. Given a set of data points to be fitted, the method obtains a series of fitting curves (or surfaces) by iteratively updating the control points, and the limit curve (surface) can interpolate or approximate the given data points. It avoids solving a linear system of equations directly and allows flexibility in adding constraints during the iterative process. Therefore, it has been widely used in geometric design and related fields.
The study of the iterative method with geometric meaning can be traced back to the work of scholars such as Dongxu Qi and Carl de Boor in the 1970s. In 1975, Qi et al. developed and proved the "profit and loss" algorithm for uniform cubic B-spline curves, and in 1979, de Boor independently proposed this algorithm. In 2004, Hongwei Lin and coauthors proved that non-uniform cubic B-spline curves and surfaces have the "profit and loss" property. Later, in 2005, Lin et al. proved that the curves and surfaces with normalized and totally positive basis all have this property and named it progressive iterative approximation (PIA). In 2007, Maekawa et al. changed the algebraic distance in PIA to geometric distance and named it geometric interpolation (GI). In 2008, Cheng et al. extended it to subdivision surfaces and named the method progressive interpolation (PI). Since the iteration steps of the PIA, GI, and PI algorithms are similar and all have geometric meanings, they are collectively referred to as geometric iterative methods (GIM).
PIA is now extended to several common curves and surfaces in the geometric design field, including NURBS curves and surfaces, T-spline surfaces, and implicit curves and surfaces.
Iteration methods
Generally, progressive-iterative approximation (PIA) can be divided into interpolation and approximation schemes. In interpolation algorithms, the number of control points is equal to that of the data points; in approximation algorithms, the number of control points can be less than that of the data points. Specifically, there are some representative iteration methods—such as local-PIA, implicit-PIA, fairing-PIA, and isogeometric least-squares progressive-iterative approximation (IG-LSPIA)—that are specialized for solving the isogeometric analysis problem.
Interpolation scheme: PIA
In interpolation algorithms of PIA, every data point is used as a control point. To facilitate the description of the PIA iteration format for different forms of curves and surfaces, the following formula is uniformly used:
For example:
If is a B-spline curve, then is a scalar, is a B-spline basis function, and denotes the control point;
If is a B-spline patch with control points, then and , where and are B-spline basis functions;
If is a trivariate B-spline solid with control points, then and , where , , and are B-spline basis functions.
Additionally, this can be applied to NURBS curves and surfaces, T-spline surfaces, and triangular Bernstein–Bézier surfaces.
Given an ordered data set with parameters satisfying for , the initial fitting curve is:
where the initial control points of the initial fitting curve can be randomly selected. Suppose that after the th iteration, the th fitting curve is generated by
To construct the st curve, we first calculate the difference vectors,
and use them to update the control points by
which leads to the st fitting curve:
In this way, we obtain a sequence of curves , which converges to a limit curve that interpolates the give data points, i.e.,
Approximation scheme: LSPIA
For the B-spline curve and surface fitting problem, Deng and Lin proposed a least-squares progressive–iterative approximation (LSPIA), which allows the number of control points to be less than the number of the data points and is more suitable for large-scale data fitting problems.
Assume there exists data points and control points, where . Start with equation (), which gives the th fitting curve as
To generate the th fitting curve, first compute the difference vectors for the data points
and then the difference vectors for the control points
where is the index set of the data points in the th group, whose parameters fall in the local support of the th basis function, i.e., . The are weights that guarantee the convergence of the algorithm, usually taken as .
Finally, the control points of the th curve are updated by leading to the th fitting curve . In this way, we obtain a sequence of curve, and the limit curve converges to the least-squares fitting result to the given data points.
Local-PIA
In the local-PIA method, the control points are divided into active and fixed control points, whose subscripts are denoted as and , respectively. Assume that, the th fitting curve is , where the fixed control points satisfy
Then, on the one hand, the iterative formula of the difference vector corresponding to the fixed control points is
On the other hand, the iterative formula of the difference vector corresponding to the active control points is
Arranging the above difference vectors into a one-dimensional sequence,
the local iteration format in matrix form is,
where is the iteration matrix:
where and are the identity matrices and
The above local iteration format converges and can be extended to blending surfaces and subdivision surfaces.
Implicit-PIA
The PIA format for implicit curve and surface reconstruction is presented in the following. Given an ordered point cloud and a unit normal vector on the data points, we want to reconstruct an implicit curve from the given point cloud. To avoid a trivial solution, some offset points are added to the point cloud. They are offset by a distance along the unit normal vector of each point
Assume that is the value of the implicit function at the offset point
Let the implicit curve after the th iteration be
where is the control point.
Define the difference vector of data points as
Next, calculate the difference vector of control coefficients
where is the convergence coefficient. As a result, the new control coefficients are
leading to the new algebraic B-spline curve
The above procedure is carried out iteratively to generate a sequence of algebraic B-spline functions . The sequence converges to a minimization problem with constraints when the initial control coefficients .
Assume that the implicit surface generated after the th iteration is
the iteration format is similar to that of the curve case.
Fairing-PIA
To develop fairing-PIA, we first define the functionals as follows:
where represents the th derivative of the basis function , (e.g. B-spline basis function).
Let the curve after the th iteration be
To construct the new curve , we first calculate the st difference vectors for data points,
Then, the fitting difference vectors and the fairing vectors for control points are calculated by
Finally, the control points of the st curve are produced by
where is a normalization weight, and is a smoothing weight corresponding to the th control point. The smoothing weights can be employed to adjust the smoothness individually, thus bringing great flexibility for smoothness. The larger the smoothing weight is, the smoother the generated curve is. The new curve is obtained as follows
In this way, we obtain a sequence of curves . The sequence converges to the solution of the conventional fairing method based on energy minimization when all smoothing weights are equal (). Similarly, the fairing-PIA can be extended to the surface case.
IG-LSPIA
Isogeometric least-squares progressive-iterative approximation (IG-LSPIA). Given a boundary value problem
where is the unknown solution, is the differential operator, is the boundary operator, and and are the continuous functions. In the isogeometric analysis method, NURBS basis functions are used as shape functions to solve the numerical solution of this boundary value problem. The same basis functions are applied to represent the numerical solution and the geometric mapping :
where denotes the NURBS basis function, is the control coefficient. After substituting the collocation points into the strong form of PDE, we obtain a discretized problem
where and denote the subscripts of internal and boundary collocation points, respectively.
Arranging the control coefficients of the numerical solution into an -dimensional column vector , the discretized problem can be reformulated in matrix form as
where is the collocation matrix and is the load vector.
Assume that the discretized load values are data points to be fitted. Given the initial guess of the control coefficients , we obtain an initial blending function
where , , represents the combination of different order derivatives of the NURBS basis functions determined using the operators and
where and indicate the interior and boundary of the parameter domain, respectively. Each corresponds to the th control coefficient. Assume that and are the index sets of the internal and boundary control coefficients, respectively. Without loss of generality, we further assume that the boundary control coefficients have been obtained using strong or weak imposition and are fixed, i.e.,
The th blending function, generated after the th iteration of IG-LSPIA, is assumed to be as follows:
Then, the difference vectors for collocation points (DCP) in the st iteration are obtained using
Moreover, group all load values whose parameters fall in the local support of the th derivatives function, i.e., , into the th group corresponding to the th control coefficient, and denote the index set of the th group of load values as . Lastly, the differences for control coefficients (DCC) can be constructed as follows:
where is a normalization weight to guarantee the convergence of the algorithm.
Thus, the new control coefficients are updated via the following formula,
Consequently, the st blending function is generated as follows:
The above iteration process is performed until the desired fitting precision is reached and a sequence of blending functions is obtained
The IG-LSPIA converges to the solution of a constrained least-squares collocation problem.
Proof of convergence
Non-singular case
Let be the number of control points and be the number of data points.
If , the PIA iterative format in matrix form is
where
The convergence of the PIA is related to the properties of the collocation matrix. If the spectral radius of the iteration matrix is less than , then the PIA is convergent. It has been shown that the PIA methods are convergent for Bézier curves and surfaces, B-spline curves and surfaces, NURBS curves and surfaces, triangular Bernstein–Bézier surfaces, and subdivision surfaces (Loop, Catmull-Clark, Doo-Sabin).
If , the LSPIA in matrix form is
When the matrix is nonsingular, the following results can be obtained:
Proof Since is nonsingular, and , then . Moreover,
In summary, .
Proof From the matrix form of iterative format, we obtain the following:
According to above Lemma, the spectral radius of the matrix satisfies
and thus the spectral radius of the iteration matrix satisfies
When
As a result,
i.e., , which is equivalent to the normal equation of the fitting problem. Hence, the LSPIA algorithm converges to the least squares result for a given sequence of points.
Singular case
Lin et al. showed that LSPIA converges even when the iteration matrix is singular.
Acceleration algorithms and others
Precondition: Liu et al. proposed a preconditioned PIA for Bézier surfaces via the diagonally compensated reduction method, effectively improving the accuracy and efficiency of the classical algorithm.
Iteration matrix inverse approximation: Sajavičius improved the LSPIA based on the matrix approximate inverse method. In each iteration step, the approximate inverse of the coefficient matrix of the least-squares fitting problem is first computed and then used as the weight to adjust the control points.
Optimal weight: Lu initially presented a weighted progressive-iterative approximation (WPIA) that introduces the optimal weight of difference vectors for control points to accelerate the convergence. Moreover, Zhang et al. proposed a weighted local PIA format for tensor Bézier surfaces. Li et al. assigned initial weights to each data point, and the weights of the interpolated points are determined adaptively during the iterative process.
Acceleration with memory: In 2020, Huang et al. proposed a PIA method with memory for least square fitting (MLSPIA), which has a similar format to the momentum method. MLSPIA generates a series of fitting curves with three weights by iteratively adjusting the control points. With appropriate parameter selection, these curves converge to the least squares fit results for a given data point and are more efficient than LSPIA.
Stochastic descent strategy: Rios and Jüttle explored the relationship between LSPIA and gradient descent method and proposed a stochastic LSPIA algorithm with parameter correction.
Applications
Since PIA has obvious geometric meaning, constraints can be easily integrated in the iterations. Currently, PIA has been widely applied in many fields, such as data fitting, reverse engineering, geometric design, mesh generation, data compression, fairing curve and surface generation, and isogeometric analysis.
Data fitting
Adaptive data fitting: The control points are divided into active control points and fixed control points. In each round of iteration, if the fitting error of a data point reaches a given precision, its corresponding control point is fixed and not updated. This iterative process is repeated until all control points are fixed. The algorithm performs well on large-scale data fitting by adaptively reducing the number of active control points.
Large-scale data fitting: By combining T-spline with PIA, an incremental fitting algorithm suitable for fitting large-scale data sets is proposed. During the incremental iteration, each new round of iterations reuses information from the last round of iterations to save computation. While the convergence speed of the traditional point-by-point iterative algorithm decreases as the number of control points increases, in PIA the computation of each iteration step is unrelated to the number of control points; this gives PIA a powerful capability for data fitting.
Local fitting: Based on the local property of PIA, a series of local PIA formats have been proposed.
Implicit reconstruction
For implicit curve and surface reconstruction, PIA avoids the additional zero level set and regularization term, which greatly improves the speed of the reconstruction algorithm.
Offset curve approximation
Firstly, the data points are sampled on the original curve. Then, the initial polynomial approximation curve or rational approximation curve of the offset curve is generated from these sampled points. Finally, the offset curve is approximated iteratively using the PIA method.
Mesh generation
Given a triangular mesh model as input, the algorithm first constructs the initial hexahedral mesh, then extracts the quadrilateral mesh of the surface as the initial boundary mesh. During the iterations, the movement of each mesh vertex is constrained to ensure the validity of the mesh. Finally, the hexahedral model is fitted to the given input model. The algorithm can guarantee the validity of the generated hexahedral mesh, i.e., the Jacobi value at each mesh vertex is greater than zero.
Data compression
First, the image data are converted into a one-dimensional sequence by Hilbert scan. Then, these data points are fitted by LSPIA to generate a Hilbert curve. Finally, the Hilbert curve is sampled, and the compressed image can be reconstructed. This method can well preserve the neighborhood information of pixels.
Fairing curve and surface generation
Given a data point set, we first define the fairing functional, and calculate the fitting difference vector and the fairing vector of the control point; then, adjust the control points with fairing weights. According to the above steps, the fairing curve and surface can be generated iteratively. Due to the sufficient fairing parameters, the method can achieve global or local fairing. It is also flexible to adjust knot vectors, fairing weights, or data parameterization after each round of iteration. The traditional energy-minimization method is a special case of this method, i.e., when the smooth weights are all the same.
Isogeometric analysis
The discretized load values are regarded as the set of data points, and the combination of the basis functions and their derivative functions is used as the blending function for fitting. The method automatically adjusts the degrees of freedom of the numerical solution of the partial differential equation according to the fitting result of the blending function to the load values. In addition, the average iteration time per step is only related to the number of data points (i.e., collocation points) and unrelated to the number of control coefficients.
References
Computer-aided design
Computer graphics
Computational geometry
Geometric algorithms
Curve fitting | Progressive-iterative approximation method | [
"Mathematics",
"Engineering"
] | 3,411 | [
"Computer-aided design",
"Computational geometry",
"Design engineering",
"Computational mathematics"
] |
74,444,880 | https://en.wikipedia.org/wiki/Isbell%27s%20zigzag%20theorem | Isbell's zigzag theorem, a theorem of abstract algebra characterizing the notion of a dominion, was introduced by American mathematician John R. Isbell in 1966. Dominion is a concept in semigroup theory, within the study of the properties of epimorphisms. For example, let is a subsemigroup of containing , the inclusion map is an epimorphism if and only if , furthermore, a map is an epimorphism if and only if . The categories of rings and semigroups are examples of categories with non-surjective epimorphism, and the Zig-zag theorem gives necessary and sufficient conditions for determining whether or not a given morphism is epi. Proofs of this theorem are topological in nature, beginning with for semigroups, and continuing by , completing Isbell's original proof. The pure algebraic proofs were given by and .
Statement
Zig-zag
Zig-zag: If is a submonoid of a monoid (or a subsemigroup of a semigroup) , then a system of equalities;
in which and , is called a zig-zag of length in over with value . By the spine of the zig-zag we mean the ordered -tuple .
Dominion
Dominion: Let be a submonoid of a monoid (or a subsemigroup of a semigroup) . The dominion is the set of all elements such that, for all homomorphisms coinciding on , .
We call a subsemigroup of a semigroup closed
if , and dense if .
Isbell's zigzag theorem
Isbell's zigzag theorem:
If is a submonoid of a monoid then if and only if either or there exists a zig-zag in over with value that is, there is a sequence of factorizations of of the form
This statement also holds for semigroups.
For monoids, this theorem can be written more concisely:
Let be a monoid, let be a submonoid of , and let . Then if and only if in the tensor product .
Application
Let be a commutative subsemigroup of a semigroup . Then is commutative.
Every epimorphism from a finite commutative semigroup to another semigroup is surjective.
Inverse semigroups are absolutely closed.
Example of non-surjective epimorphism in the category of rings: The inclusion is an epimorphism in the category of all rings and ring homomorphisms by proving that any pair of ring homomorphisms which agree on are fact equal.
We show that: Let to be ring homomorphisms, and , . When for all , then for all .
as required.
See also
Epimorphisms
References
Citations
Bibliography
Further reading
Footnote
External links
Semigroup theory
Theorems in group theory | Isbell's zigzag theorem | [
"Mathematics"
] | 603 | [
"Semigroup theory",
"Fields of abstract algebra",
"Mathematical structures",
"Algebraic structures"
] |
74,445,140 | https://en.wikipedia.org/wiki/Populus%20pruinosa | Populus pruinosa is a species of flowering plant in the family Salicaceae, native to Central Asia, Afghanistan, and Xinjiang in China. A halophytic tree usually tall, but occasionally reaching , it is often found growing in basins. Its bark is grayish-yellow, its branchlets and young sprouts are densely tomentulose and gray in color, and its leaves are tomentulose and grayish-blue.
References
pruinosa
Halophytes
Flora of Central Asia
Flora of Afghanistan
Flora of Xinjiang
Plants described in 1845 | Populus pruinosa | [
"Chemistry"
] | 114 | [
"Halophytes",
"Salts"
] |
74,445,519 | https://en.wikipedia.org/wiki/German%20Human%20Genome-Phenome%20Archive | The German Human Genome-Phenome Archive (GHGA) is a consortium within the national data infrastructure (NFDI). GHGA aims to create a secure national data infrastructure for human omics data in order to make these data available for scientific research while preventing the misuse of data.
Goals/Ambitions
The main goal of GHGA is to establish a national infrastructure for human omics data. These data are to be made accessible in accordance with the FAIR principles. This enables the secondary use of data primarily collected in diagnostics, personalized medicine and biomedical research.
Genomic data are sensitive, personal data and require careful protection to minimise the risk of re-identification of the data subject. GHGA implements the legal requirements specific to Germany (GDPR) and thus allows human omics data to be brought together, stored and analysed in a secure, uniform and data protection-compliant framework.
Goals:
Establishing a national, secure long-term archive of human omics data.
Tackling legal and ethical obstacles for data sharing through the implementation of an unified ethico-legal framework.
Increasing the FAIRness of omics data and facilitating its embedding in national and international data resources and infrastructures.
Democratising access to and analysis of large-scale omics data for research via a cloud-based analytics platform.
Increasing the value of research data by integrating multiple omics modalities and linking omics data with phenotype data.
Training the next generation of scientists in the efficient and responsible use and management of omics data in research.
Resources/ Services
GHGA is developing a variety of services for the research community. Aside from setting up a data portal, the focus is on tackling ethical and legal issues. GHGA also works on analysing data by co-developing standardised bioinformatics analysis methods.
Infrastructure for GDPR-compliant sharing of human omics data for secondary purposes
Standardised, interoperable and reproducible omics workflows for the scientific community
Legal and ethical basis for omics research, including the development of a legal basis for data sharing and tools on consent
Metadata model to provide standardised information on submitted omics data and to facilitate data findability
Educational material for and about omics research and its societal relevance
National and international context
Within Germany, GHGA is partnering with genomDE as a research data infrastructure. genomDE is the national strategy for genomic medicine and is intended to make the use of genomic information an "innovative component of standard medical care in Germany".
Within Europe, GHGA is part of the federated network of the European Genome-phenome Archive (EGA). Functioning as the German node of EGA, the data from GHGA are findable and usable with data from other European studies via compatible standards and metadata. In the context of the GDI project funded by the European Commission and the Federal Ministry of Education and Research (Germany), GHGA ensures that German data collections can also be used within the framework of the „1+ Million Genomes“-Initiative
History
On 4 July 2019, the German Cancer Research Center, as the applicant institution, submitted the binding pre-application (Letter of Intent) to the DFG Head Office. On 26 June 2020, GHGA was approved by a funding decision of the Joint Science Conference together with eight other consortia in the first application round.
In March 2023, the GHGA Metadata Catalog was made available as part of the project’s first phase. The GHGA Metadata Catalog is a public portal for searching study data from German research institutions.
Participating institutions
German Cancer Research Center
University of Tübingen
University Hospital Tübingen
Charité
Berlin Institute for Health at Charité
Technical University of Munich
European Molecular Biology Laboratory
Max Delbrück Center for Molecular Medicine in the Helmholtz Association
TU Dresden
University Hospital Heidelberg
Heidelberg University
University of Cologne
Kiel University
Helmholtz Zentrum München
German Center for Neurodegenerative Diseases
Saarland University
NAKO e.V.
Partner institutions
European Bioinformatics Institute
Helmholtz Centre for Information Security
Leibniz Supercomputing Centre
Helmholtz Centre for Infection Research
National Centre for Tumor Diseases
References
Human genome projects | German Human Genome-Phenome Archive | [
"Biology"
] | 862 | [
"Human genome projects",
"Genome projects"
] |
74,445,921 | https://en.wikipedia.org/wiki/Ghodsi%20Mohammadi%20Ziarani | Ghodsi Mohammadi Ziarani (born 1964) is an Iranian chemist and Professor of Organic Chemistry at Alzahra University. Mohammadi Ziarani is among the most-cited Iranian researchers and is known for her works on organic chemistry, nanochemistry, multi-component reactions, natural product synthesis, and asymmetric synthesis.
Books
Metal - Free Synthetic Organic Dyes, Ghodsi Mohammadi Ziarani, Razieh Moradi, Negar Lashgari, Hendrik G. Kruger, Elsevier 2018, ISBN 9780128156476
References
External links
Living people
Iranian organic chemists
Academic staff of Al-Zahra University
1964 births
Université Laval alumni
Kharazmi University alumni
Iranian women chemists | Ghodsi Mohammadi Ziarani | [
"Chemistry"
] | 153 | [
"Organic chemists",
"Iranian organic chemists"
] |
74,446,282 | https://en.wikipedia.org/wiki/Competence%20%28polyseme%29 | Competence (also called competency or capability) is a polyseme indicating a variety of different notions. In current literature, three notions are most evident. The first notion is that of a general competence, which is someone's capacity or ability to perform effectively on a specified set of behavioral attributes (e.g. performances, skills, attitudes, tasks, roles, talents, and so forth). The second notion refers to someone's capacity or ability to successfully perform a specific behavioral attribute — be it overt or covert — like learning a language, reading a book or playing a musical instrument. In both notions, someone may be qualified as being competent. In a third notion, a competence is the behavioral attribute itself, instead of a general or specific capacity or ability. One may for example excel at the competence of baking, at the competency of ceramics, or at the capability of reflexivity.
The pluralized forms of competence and competency are respectively competences and competencies. According to Boyatzis (2008) competencies are part of a behavioral approach to emotional, social, and cognitive intelligence. Moreover, competence is measurable and can be developed through training. In the context of human resources, practice may enable someone to improve the efficiency or performance of an activity or a job.
Concepts like knowledge, expertise, values or desires are not behavioral attributes but can be contained in behavior once executed. Take for example sharing knowledge or actualizing a desire.
Etymology
The term 'competence' isn't novel and predates literature in the 20th century. It first entered professional literature via the article Motivation reconsidered: The concept of competence authored by R.W. White in 1959. He introduced the term competence to describe those personality characteristics associated with high motivation and superior performance. Postulating a relationship between achieved capacity and competence motivation, White defined competence as an ‘effective interaction (of the individual) with the environment’.
In the late 1960s, the 'Competence movement' had been initiated by David McClelland. The movement has its origins in the conspicuous failure of educational qualifications to predict occupational success. The term gained traction in 1973, when McClelland wrote a seminal paper entitled Testing for Competence Rather Than for Intelligence. McClelland followed White's approach in arguing that capacity is more important than intelligence.
The term has since been popularized, most notably, by individuals such as:
Thomas F. Gilbert, in Human competence: engineering worthy performance (1978);
Richard E. Boyatzis, in The Competent Manager: A Model for Effective Performance (1982);
C. K. Prahalad and Gary Hamel, in The Core Competence of the Corporation (1990) and
Daniel Goleman, in Emotional Intelligence: Why It Can Matter More Than IQ (1995).
Its uses vary widely, which has led to considerable misunderstanding. Studies on competence indicate that competence covers a very complicated and extensive range of disciplines, ranging from human resources to psychology and from science to education, with various scholars holding different interpretations of the term. According to Zemke (1982), the terms 'competency', 'competence', and their affiliated counterparts are akin to "Humpty Dumpty words" that derive their meaning solely from the interpreter's intent. This issue arises not due to ill intentions, ignorance, or commercial motives, but stems from procedural and philosophical variations among those vying to establish and shape the concept. This involves constructing the blueprint for how the broader population will incorporate competencies into their routine training endeavors.
Competence and capability
In an influential paper from 1992, Dorothy A. Leonard took on a knowledge-based approach when discussing competency in the context of managerial and technical systems. She defined a 'core capability' as a set of knowledge that distinguishes a company strategically. Core capability wasn't new concept, back in the '90s. Other scholars have also referred to it using various terms like distinctive competences, core competencies, resource deployments, and invisible assets. Leonard was however the first to explicitly plot core capabilities against core rigidities. In a narrow sense, core rigidities represent inappropriate knowledge-sets that can hinder a firm's progress. Following the release of this paper, a tendency has grown to employ the terms competencies and capabilities interchangeably, often without clear differentiation. In other instances, a more precise definition is given priority over a highly inclusive scope.
Competence and performance
Performance has been described by some scholars as the capacity or ability to accomplish specific tasks. Noteworthy figures such as White, McClelland, and Boyatzis have all upheld the notion that competence is tantamount to effective performance. Furthermore, a consensus has arisen among scholars like McClelland, Boyatzis, Spencer and Spencer, as well as H.F. Evarts, regarding the similarity between competence and superior performance. Authors including McClelland, Kanungo and Misra, and Martin and Staines consider competence to be successful performance. All these conceptualizations corroborate performance's role as a neutral carrier for competence. Oftentimes, the term "performance" is extended to delineate the capacity or ability of mechanical, rather than biological systems, to fulfill certain tasks. This task-oriented approach diverges from a behavioral approach as to evade anthropomorphisms. Amidst ongoing developments in artificial intelligence, mechanistic systems receive anthropomorphic characteristics increasingly often. The way performance is being defined mirrors attempts made by authors to emphasize core competence in a similar light. This attempt has failed however, since a consensus on consistent use of competence and competency as separate terms has not been established.
Competence and intelligence
In his influential paper 'Testing for Competence Rather Than for Intelligence' David McClelland sheds light on the advantages of measuring competence over intelligence. McClelland points out that the traits measured by traditional intelligence tests do not reliably correlate with high-level performance in society. He goes on to identify a significant error in categorizing these abilities as "general intelligence", advocating for a more nuanced approach. McClelland's approach acknowledges the multifaceted nature of human capabilities, signaling a departure from a singular focus on cognitive or intellectual abilities.
McClelland emphasizes that there's no solid evidence to suggest that human traits, including cognitive abilities, are innate and cannot be altered. This perspective aligns with the idea that individuals have the capacity to grow, learn, and develop new skills throughout their lives. McClelland's perspective encourages a move away from the pursuit of pinpointing abstract ability factors. Instead, he urges the adoption of assessments that align with the evolving nature of human potential. He suggests that tests rooted in life-outcome behaviors can validate their worth by demonstrating that a person's ability to perform such tasks improves as their competence in those areas increases.
Competence typologies
Atomistic and holistic competence
In 1996, a paper titled "What is competence?" was published by Hager and Gonczi, which addresses an apparent tension between atomistic and holistic competence. Hager and Gonczi criticize the misconception among scholars that labeling an approach as atomistic automatically warrants its rejection without further justification. They emphasize the necessity of justifying the application of any competence standard. To illustrate their point, they draw an analogy with chemistry, where discrete atoms come together to form molecules with distinct properties. Similarly, in the interpretation of competence, especially occupational competence, the authors assert that breaking down an occupation into isolated tasks, as done in a task-oriented approach, is inherently atomistic. This approach fails to provide a synthesis of the tasks, thereby undermining the complex nature of the occupation and corresponding competences. On the other hand, Hager and Gonczi caution against adhering strictly to a rigid holism that dismisses all forms of analysis. They acknowledge that some degree of atomism in competence approaches may be necessary, as long as it is complemented by an appropriate amount of holism. Finding the right balance between analysis and synthesis is crucial for understanding and developing competency standards effectively.
Occupational competences are constructs, which are often inferred from the performance of complex tasks. In contrast, the performance of a task is directly observable and doesn't have to be inferred. Unlike atomistic tasks, holistic tasks are not discrete and independent. For example, practice and assessment, will typically involve a simultaneity of several tasks. Furthermore, these tasks will involve ‘situational understanding’, which means that a worker must take into account multiple contexts while being involved in practice. Although tasks are given as an example, Hager and Gonczi stress the importance of integrating competence standards as to also include attributes. Forgetting about attributes and concentrating solely on tasks may lead someone to lapse into a narrow view of occupational competence, they insist. Approaches to competence that focus exclusively on either tasks or attributes ignore the complex nature of competence. Hence an integrated approach to competence standards, which integrates key tasks and attributes, is supported.
Behavioral and functional competence
The competence movement has inspired individuals from a variety of countries like the United States, the United Kingdom, France, Germany and Australia. Two traditions in particular have represented the early stages of the competence movement, namely the behavioral (or US) approach and the functional (or UK) approach. Multiple scholars have attempted to differentiate between these two traditions. Delamare Le Deist and Winterton (2005) are convinced that since the 1990's the behavioral conception of competence had been transformed into a broader functional conception, which includes knowledge and skills alongside behavioral characteristics. Terry Hyland (1997) offers an alternative interpretation. According to Hyland, alternative models only purport to include wide-ranging knowledge and values. He supposes that functional analysis, which would be inherent to behavioral approaches, is primarily committed to the assessment and accreditation of performance outcomes, not performance improvement. Those who wish to apply their models to value-laden occupations, such as teaching, run into the problem that competence systems, whether these are atomistic as in the British model or allegedly holistic as in the Australian model, are concerned only with performance outcomes, not with the processes of learning and development. Chivers and Cheetham (2000) supplement that not only does the functional approach favor outcomes over processes, it heavily emphasizes occupational standards over vocational standards. Furthermore, Hyland clarifies that functional analysis can only wish to supplement or temper a behaviorist approach. Hyland hereby firmly presents the key difference between the behavioral and functional approach. Even within the predominantly behavioral approach, many conceptions of competence now include knowledge and skills alongside attitudes, behaviors, work habits, abilities and personal characteristics. The behavioral approach is promoted most notably by David McClelland, Boyatzis, and Spencer and Spencer.
Professional competence
Since the 1950s, the concept of competence has found its way into professional literature, transforming various fields and shaping the way we understand professional capabilities. Over the decades, competence models have played a significant role in mapping professions and crafting effective professional education and development programs. At its core, Mulder (2014) suggests, competence development is a socio-constructivist journey. It thrives on the dynamic interplay of social interactions, wherein professionals engage in context-specific quests to improve their capacity.
There have been numerous competence frameworks supporting competence development. One such initiative is competence-based teacher education (CBTE), which came about during the 1970s. Rooted in behavioristic psychology and educational philosophy, CBTE sought to prepare students for specific functions. However, the undertaken was not devoid of challenges and critiques. In response to the limitations of function-oriented perspectives, the concept of integrated occupationalism emerged. Unlike a narrow focus on job profiles, this approach embraced a broader vision. It emphasized holistic, generic and integrated capabilities that are vital for navigating the complexities of occupational roles. On top of integrated occupationalism, situated professionalism emerged. This theory established a nexus between competence and the context in which professionals interact. At the core lies the cultivation of a professional identity, reflecting the principles of situated cognition. It delves into the idea that competence is shaped by the expectations of stakeholders, guiding the professional towards desired actions and outcomes. The culmination of these endeavors has resulted in the enrichment of professional and practice-based learning across many fields.
Personal competence
In his study, Day (1994) points out that beginning in the 1980s, there has been a growing acknowledgment within both business and education sectors regarding the development of personal profiles and portfolios. As a result, employees are now significantly more involved in identifying their individual learning needs. This has led to the recognition and acceptance of personal development as an integral aspect of professional growth. Furthermore, Day's study indicates that personal competences can be examined separately from one's professional competence, though it might be useful to consider both.
Scholars frequently examine interpersonal and intrapersonal competences. For instance, Park et al. (2017) conducted a study on a tripartite taxonomy of character, investigating interpersonal, intrapersonal, and intellectual competences in children. Park et al. has built upon the competency clusters introduced by the National Research Council (NRC). The tripartite taxonomy was however already apparent since B. B. Rothenberg released her study 'Children's social sensitivity and the relationship to interpersonal competence, intrapersonal comfort, and intellectual level' in 1970.
Park et. al has gathered evidence supporting the usefulness of a tripartite taxonomy of character within the school context. The study defines its taxonomy as follows: interpersonal character includes gratitude, social intelligence, and self-control, while intrapersonal character involves academic performance and perseverance. Lastly, intellectual character includes curiosity and enthusiasm. Based on this research orientation, Park et. al. found that interpersonal competence predicts positive peer relations, intrapersonal competence predicts grades and regulated behavior, and intellectual competence predicts class participation and active learning.
Core competence
Core competence can be interpreted as the competence of an organization, but may also pertain to a group of individuals operating within an organization. Core competences encompass the amassed capabilities within an organization, in particular attempts to harmonize professional skills and technological innovation. At its essence, core competence includes involvement, commitment and communication, transcending organizational boundaries and hierarchies, while fostering a culture of inclusivity within the organization.
At the nexus between 'core competences' and 'end products' are the core products. Core products are the physical components (e.g. subassemblies) that increase the value of the end products. Well-targeted core products allow a company to optimize its development stage and go-to-market strategy. By increasing the number of application arenas for its core products, a company can systematically improve efficiency, and reduce expenses and risks associated with novel product creation. In essence, well-targeted core products have the potential to yield economies of both scale and scope.
Metacompetence
According to Brown (1993), metacompetences refer to advanced capabilities associated with learning, creating, adapting and anticipating, rather than merely showcasing a capability to perform on a specific task. This is particularly evident in learning and reflecting, which are crucial for developing mental frameworks. Metacompetences often encompass the concept of 'learning to learn'. Metacompetence can also be summarized as the capability to improve one's competences.
Other typologies
Various other typologies exist to categorize competence in a wider context. These include:
Social competence: the ability to navigate social interactions effectively.
Cultural competence: the ability to meet cultural expectations.
Cross-cultural competence: the ability to adapt effectively in cross-cultural environments.
Communicative competence: the ability to communicate adequately, both verbally and nonverbally.
Linguistic competence: the mastery of a specific language, including grammar, vocabulary, and pronunciation.
This list is not exhaustive. Competence typologies cover a wide range, with new typologies emerging regularly to address specific contexts.
Disciplines
Education
Growing demand for knowledge acquisition across various professional and personal spheres has raised the importance of effective education. Beginning in the late 1980s, governmental intervention worldwide has led to a considerable reconsideration of competence outcomes at all levels of the educational spectrum, encompassing elementary, secondary, tertiary, vocational, empirical and adult education. The value and valuation of these outcomes serve as criteria for assessing the productivity and quality of the educational system. According to Klieme et. al. (2008), effective education could no longer be supported by a rigid canon of intergenerational knowledge and professional qualifications. A more dynamic approach is needed to meet the everchanging competence requirements.
Academia
Academic competence, seen as a subset of student competence, hinges on the effective application of study skills. According to a study conducted by Gettinger and Seiberts (2002), students across all grade levels who possess strong study skills tend to excel academically. However, they suggest, for study skills to be truly effective in promoting academic competence, students must exhibit enough willingness and motivation to engage in studying. Student engagement and proper utilization of study skills are closely intertwined, both bolstering academic competence. Unfortunately, many students pass through the educational system without attaining the level of academic competence necessary for academic success. In light of this, Gettinger and Seiberts emphasize prioritizing research aimed at implementing effective classroom strategies and promoting effective study habits among all students.
Human resources
Leading up to the 1990s, the application of 'capability' as a behavioral approach (competence) had primarily centered around innovation and learning experiences aimed at fostering capability in both educational and workplace settings, as noted by Stephenson & Weil (1992) and Graves (1993). During the 1990s, in particular in Australia, people grew hesitant of the behavioral approach. The association between capability and human resources strengthened, shifting away the attention from education. Hase & Davis (1999) explains this transgression as follows: while competencies form the foundation of capability, competencies alone may be insufficient for achieving optimal human resource management. They proclaim that competencies are rooted in a traditional 'pedagogical paradigm', which fails to fully equip individuals with the attributes needed to succeed in a workplace setting.
Miscellaneous
Other relevant disciplines, wherein competence plays a role, are among others science, pedagogy, professional psychology, healthcare, and engineering.
See also
References
Human behavior
Human resource management
Incompetence | Competence (polyseme) | [
"Biology"
] | 3,779 | [
"Incompetence",
"Behavior",
"Human behavior"
] |
74,446,434 | https://en.wikipedia.org/wiki/Vital%20Materials | Vital Materials is a company established in 1995 that primarily refines minor metals.
History
Zhu Shihui, formerly an employee of Sumitomo, founded the firm in 1995. Vital Materials purchased a large amount of indium at auction formerly held by Fanya Metal Exchange in 2020.
References
1995 establishments in China
Metals
Companies of China
Companies established in 1995 | Vital Materials | [
"Chemistry"
] | 70 | [
"Metals"
] |
74,446,691 | https://en.wikipedia.org/wiki/Knapsack%20auction | A knapsack auction is an auction in which several identical items are sold, and there are several bidders with different valuations interested in different amounts of items. The goal is to choose a subset of the bidders with a total demand, at most, the number of items and, subject to that, a maximum total value. Finding this set of bidders requires solving an instance of the knapsack problem, which explains the term "knapsack auction".
An example application of a knapsack auction is auctioning broadcast time among advertisers. Here, the items are the time units (e.g., seconds). Each advertiser has an adversitement of a different length (different number of seconds) and a different value for an advertisement. The goal is to select a subset of advertisements to serve in a time slot of a specific length to maximize the total value.
Notation
There are m identical items and n different bidders. The preferences of each bidder i are given by two numbers:
A demand si - an integer that determines how many items this bidder wants. The bidder needs precisely this number of items and has no use for more or fewer items.
A value vi - a number that determines how much money the bidder expects to gain from receiving exactly si items.
A feasible outcome of the auction is a subset W of winning bidders, such that their total demand is at most m: . The value of a set W of winners is the sum of values of the winners: . The goal is to find a feasible set of winners with a maximum total value.
In the broadcast time example, if there are 5 minutes allocated for advertisements, then m=300 (the number of seconds), n=the number of potential advertisers, si=the length of i's advertisement in seconds, and vi=the money that i expects to gain if his advertisement is broadcast.
Baseline solutions
If the demands and values of all bidders are publicly known, then the problem can be solved by any algorithm for the knapsack problem. The problem is NP-hard, but it has efficient constant-factor approximation algorithms as well as an FPTAS. In practice, usually the demands si are publicly known (e.g., the length of the advertisement of each advertiser must be known), but the valuations vi are the private information of the bidders. Therefore, the auction mechanism should incentivize the bidders to reveal their true valuations.
The VCG auction is a truthful mechanism that can be used to maximize the sum of values while incentivizing agents to reveal their true values. However, it only works if the outcome maximizes the values; it does not work with approximations (if the outcome is only approximately optimal, then VCG is no longer truthful). Finding the optimal outcome cannot be done in polynomial time unless P=NP. This raises the question: are there truthful mechanisms that work in polynomial time and attain an approximately-optimal outcome?
Truthful approximation mechanisms
Mu'alem and Nisan gave the first affirmative answer to this question: they showed that combining two greedy algorithms yields a truthful 2-factor approximation mechanism.
Briest, Krysta and Vocking improved this result by showing a truthful FPTAS.
Dutting, Gkatzelis and Roughgarden presented a truthful deferred-acceptance auction that attains an O(log m) approximation, and proved that no deferred-acceptance auction can achieve a better approximation. This shows a separation between the general class of truthful auctions and the sub-class of deferred-acceptance auctions.
References
Types of auction
Mechanism design | Knapsack auction | [
"Mathematics"
] | 762 | [
"Game theory",
"Mechanism design"
] |
74,448,567 | https://en.wikipedia.org/wiki/LK-99 | LK-99 (from the Lee-Kim 1999 research), also called PCPOSOS, is a gray–black, polycrystalline compound, identified as a copper-doped lead‒oxyapatite. A team from Korea University led by Lee Sukbae () and Kim Ji-Hoon () began studying this material as a potential superconductor starting in 1999. In July 2023, they published preprints claiming that it acts as a room-temperature superconductor at temperatures of up to at ambient pressure.
Many different researchers have attempted to replicate the work, and were able to reach initial results within weeks, as the process of producing the material is relatively straightforward. By mid-August 2023, the consensus was that LK-99 is not a superconductor at room temperature, and is an insulator in pure form.
As of 12 February 2024, no replications had gone through the peer review process of a journal, but some had been reviewed by a materials science lab. A number of replication attempts identified non-superconducting ferromagnetic and diamagnetic causes for observations that suggested superconductivity. A prominent cause was a copper sulfide impurity occurring during the proposed synthesis, which can produce resistance drops, lambda transition in heat capacity, and magnetic response in small samples.
After the initial preprints were published, Lee claimed they were incomplete, and coauthor Kim Hyun-Tak () said one of the papers contained flaws.
Chemical properties and structure
The chemical composition of LK-99 is approximately Pb9Cu(PO4)6O, in which— compared to pure lead-apatite (Pb10(PO4)6O)— approximately one quarter of Pb(II) ions in position 2 of the apatite structure are replaced by Cu(II) ions.
The structure is similar to that of apatite, space group P63/m (No. 176).
Synthesis
Lee et al. provide a method for chemical synthesis of LK-99 in three steps. First they produce lanarkite from a 1:1 molar mixing of lead(II) oxide (PbO) and lead(II) sulfate (Pb(SO4)) powders, and heating at for 24 hours:
PbO + Pb(SO4) → Pb2(SO4)O.
Then, copper(I) phosphide (Cu3P) is produced by mixing copper (Cu) and phosphorus (P) powders in a 3:1 molar ratio in a sealed tube under a vacuum and heated to for 48 hours:
3 Cu + P → Cu3P.
Then, lanarkite and copper phosphide crystals are ground into a powder, placed in a sealed tube under a vacuum, and heated to for between 5‒20 hours:
Pb2(SO4)O + Cu3P → Pb10-Cu(PO4)6O + S (g), where 0.9 < x < 1.1.
There were a number of problems with the above synthesis from the initial paper. The reaction is not balanced, and others reported the presence of copper(I) sulfide () as well. For a balanced reaction might be:
5 .
Many syntheses produced fragmentary results in different phases, where some of the resulting fragments were responsive to magnetic fields, other fragments were not. The first synthesis to produce pure crystals found them to be diamagnetic insulators.
Physical properties
Some small LK-99 samples were reported to show strong diamagnetic properties, including a response confusingly referred to as "partial levitation" over a magnet. This was misinterpreted by some as a sign of superconductivity, although it is a sign of regular diamagnetism or ferromagnetism.
While initial preprints claimed the material was a room-temperature superconductor, they did not report observing any definitive features of superconductivity, such as zero resistance, the Meissner effect, flux pinning, AC magnetic susceptibility, the Josephson effect, a temperature-dependent critical field and current, or a sudden jump in specific heat around the critical temperature.
As it is common for a new material to spuriously seem like a potential candidate for high-temperature superconductivity, thorough experimental reports normally demonstrate a number of these expected properties. not one of these properties had been observed by the original experiment or any replications.
Proposed mechanism for superconductivity
Partial replacement of Pb2+ ions with smaller Cu2+ ions is said to cause a 0.48% reduction in volume, creating internal stress in the material, causing a heterojunction quantum well between the Pb(1) and oxygen within the phosphate ([PO4]3−). This quantum well was proposed to be superconducting, based on a 2021 paper by Kim Hyun-Tak describing a novel and complicated theory combining ideas from a classical theory of metal-insulator transitions, the standard Bardeen–Cooper–Schrieffer theory, and the theory of hole superconductivity by J.E.Hirsch.
Response
On 31 July 2023, Sinéad Griffin of Lawrence Berkeley National Laboratory analyzed LK-99 with density functional theory (DFT), showing that its structure would have correlated isolated flat bands, and suggesting this might contribute to superconductivity. However, while other researchers agreed with the DFT analysis, a number suggested that this was not compatible with superconductivity, and that a structure different from what was described in Lee, et al. would be necessary.
Analyses by industrial and experimental physicists noted experimental and theoretical shortcomings of the published works. Shortcomings included the lack of phase diagrams spanning temperature, stoichiometry, and stress; the lack of pathways for the very high Tc of LK-99 compared to prior heavy fermion superconductors; the absence of flux pinning in any observations; the possibility of stochastic conductive artifacts in conductivity measurements; the high resistance and low current capacity of the alleged superconducting state; and the lack of direct transmission electron microscopy (TEM) of the materials.
Compound name
The name LK-99 comes from the initials of discoverers Lee and Kim, and the year of discovery (1999). The pair had worked with Tong-Seek Chair () at Korea University in the 1990s.
In 2008, they founded the Quantum Energy Research Centre (퀀텀 에너지연구소; also known as ) with other researchers from Korea University. Lee would later become CEO of , and Kim would become director of research and development.
Publication history
Lee has stated that in 2020, an initial paper was submitted to Nature, but was rejected. Similarly presented research on room-temperature superconductors (but a completely different chemical system) by Ranga P. Dias had been published in Nature earlier that year, and received with skepticism—Dias's paper would subsequently be retracted in 2022 after its data was questioned as having been falsified.
In 2020, Lee and Kim Ji-Hoon filed a patent application. A second patent application (additionally listing Young-Wan Kwon), was filed in 2021, which was published on 3 March 2023. A World Intellectual Property Organization (WIPO) patent was also published on 2 March 2023. On 4 April 2023, a Korean trademark application for "LK-99" was filed by the .
Scholarly articles and preprints
A series of academic publications summarizing initial findings came out in 2023, with a total of seven authors across four publications.
On 31 March 2023, a Korean-language paper, "Consideration for the development of room-temperature ambient-pressure superconductor (LK-99)", was submitted to the Korean Journal of Crystal Growth and Crystal Technology. It was accepted on 18 April, but was not widely read until three months later.
On 22 July 2023, two preprints appeared on arXiv. The first was submitted by Young-Wan Kwon, and listed Kwon, former CTO, as third author. The second preprint was submitted only 2 hours later by Kim Hyun-Tak, former principal researcher at the Electronics & Telecommunications Research Institute and professor at the College of William & Mary, listing himself as third author, as well as three new authors.
On 23 July, the findings were also submitted by Lee to APL Materials for peer review. On 3 August 2023, a newly-formed Korean LK-99 Verification Committee requested a high-quality sample from the original research team. The team responded that they would only provide the sample once the review process of their APL paper was completed, expected to take several weeks or months.
On 31 July 2023, a group led by Kapil Kumar published a preprint on arXiv documenting their replication attempts, which confirmed the structure using X-ray crystallography (XRD) but failed to find strong diamagnetism.
On 11 Aug 2023, P. Puphal et al., released their preprint synthesizing the first single crystals of Pb9Cu(PO4)6O finally disproving superconductivity in this chemical stoichiometry published later in APL Materials.
On 16 August 2023, Nature published an article declaring that LK-99 had been demonstrated to not be a superconductor, but rather an insulator. It cited statements by an condensed matter experimentalist at the University of California, Davis, and several studies previewed in August 2023.
Other discussion by authors
On 26 July 2023, Kim Hyun-Tak stated in an interview with the New Scientist that the first paper submitted by Kwon contained "many defects" and was submitted without his permission.
On 28 July 2023, Kwon presented the findings at a symposium held at Korea University. That same day, Yonhap News Agency published an article quoting an official from Korea University as saying that Kwon was no longer in contact with the university. The article also quoted Lee saying that Kwon had left the Research Institute four months previously.
On the same day, Kim Hyun-Tak provided The New York Times with a new video presumably showing a sample displaying strong signs of diamagnetism. The video appears to show a sample different to the one in the original preprint. On 4 August 2023, he informed SBS News that high-quality LK-99 samples may exhibit diamagnetism over 5,000 times greater than graphite, which he claimed would be inexplicable unless the substance is a superconductor.
Response
Materials scientists and superconductor researchers responded with skepticism. The highest-temperature superconductors known at the time of publication had a critical temperature of at pressures of over . The highest-temperature superconductors at atmospheric pressure (1 atm) had a critical temperature of at most .
On 2 August 2023, The Korean Society of Superconductivity and Cryogenics established a verification committee as a response to the controversy and unverified claims of LK-99, in order to arrive at conclusions over these claims. The verification committee is headed by Kim Chang-Young of Seoul National University and consists of members of the university, Sungkyunkwan University and Pohang University of Science and Technology. Upon formation, the verification committee did not agree that the two 22 July arXiv papers by Lee et al. or the publicly available videos at the time supported the claim of LK-99 being a superconductor.
the measured properties do not prove that LK-99 is a superconductor. The published material does not explain how the LK-99's magnetisation can change, demonstrate its specific heat capacity, or demonstrate it crossing its transition temperature. A more likely explanation for LK-99's magnetic response is a mix of ferromagnetism and non-superconductive diamagnetism. A number of studies found that copper(I) sulfide contamination common to the synthesis process could closely replicate the observations that inspired the initial preprints.
Public response
The claims in the 22 July papers by Lee et al. went viral on social media platforms the following week. The viral nature of the claim resulted in posts from users using pseudonyms from Russia and China claiming to have replicated LK-99 on both Twitter and Zhihu. Other viral videos described themselves as having replicated samples of LK-99 "partially levitating", most of which were found to be fake.
Scientists interviewed by the press remained skeptical, because of the quality of both the original preprints, the lack of purity in the sample they reported, and the legitimacy of the claim after the failure of previous claims of room temperature superconductivity did not show legitimacy (such as the Ranga Dias affair). The Korean Society of Superconductivity and Cryogenics expressed concern on the social and economic impacts of the preliminary and unverified LK-99 research.
A video from Huazhong University of Science and Technology uploaded on 1 August 2023 by a postdoctoral researcher on the team of Chang Haixin, apparently showed a micrometre-sized sample of LK-99 partially levitating. This went viral on Chinese social media, becoming the most viewed video on Bilibili by the next day, and a prediction market briefly put the chance of successful replication at 60%. A researcher from the Chinese Academy of Sciences refused to comment on the video for the press, dismissing the claim as "ridiculous".
In early August, people began to create memes about "floating rocks", and there was a brief surge in Korean and Chinese technology stocks, despite warnings from the Korean stock exchange against speculative bets in light of the excitement around LK-99, which eventually fell on August 8. Following the publication of the Nature article on August 16 that proclaimed LK-99 is not a superconductor, South Korean superconductor stocks fell further, as the interest about LK-99 from investors in previous weeks disappeared.
Replication attempts
After the July 2023 publication's release, independent groups reported that they had begun attempting to reproduce the synthesis, with initial results expected within weeks.
no replication attempts had yet been peer-reviewed by a journal. Of the non-peer-reviewed attempts, over 15 notable labs have published results that failed to observe any superconductivity, and a few have observed magnetic response in small fragments that could be explained by normal diamagnetism or ferromagnetism. Some demonstrated and replicated alternate causes of the observations in the original papers: Copper-deficient copper (I) sulfide has a known phase transition at from a low-temperature phase to a high-temperature superionic phase, with a sharp rise in resistivity and a λ-like-feature in the heat capacity. Furthermore, Cu2S is diamagnetic.
Only one attempt observed any sign of superconductivity: Southeast University claimed to measure very low resistance in a flake of LK-99, in one of four synthesis attempts, below a temperature of . Doubts were expressed by experts in the field, as they saw no dropoff to zero resistance, and used crude instruments that could not measure resistance below 10 μΩ (too high to distinguish superconductivity from less exotic low-temperature conductivity), and had large measurement artifacts.
Some replication efforts gained global visibility, with the aid of online replication trackers that catalogued new announcements and status updates.
Experimental studies
Selected experimental studies.
Results Key:
Theoretical studies
In the initial papers, the theoretical explanations for potential mechanisms of superconductivity in LK-99 were incomplete. Later analyses by other labs added simulations and theoretical evaluations of the material's electronic properties from first principles.
Selected theoretical studies:
See also
Bismuth strontium calcium copper oxide: Superconductivity at Tc ≈ to
Carbonaceous sulfur hydride: Purported superconductivity at Tc ≈ at 267 GPa
Lanthanum decahydride: Superconductivity at Tc = at 150 GPa
Unconventional superconductor
Salvatore Pais – Inventor with a patent referenced by a patent related to LK-99
References
Further reading
External links
This effect is a conductive copper plate induced by a magnetic.
List of replication claims, regularly updated:
Compilation of Known Replication Attempt Claims. Guderian2nd, Spacebattles Forums. Retrieved 2 August 2023.
LK-99#Online Claims. Eiri Sanada. Retrieved 2 August 2023.
2023 in science
Lead(II) compounds
Phosphates
Science and technology in South Korea
Superconductivity
Crystals in space group 176 | LK-99 | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 3,494 | [
"Physical quantities",
"Superconductivity",
"Materials science",
"Salts",
"Phosphates",
"Condensed matter physics",
"Electrical resistance and conductance"
] |
74,451,142 | https://en.wikipedia.org/wiki/Power%20%28company%29 | Power International AS (formerly Expert International AS) is a Nordic company that sells consumer electronics through subsidiaries. The company headquarters are located in Lørenskog, Norway and operates approx. 269 stores in total across Norway, Sweden, Denmark and Finland.
References
Electronics companies established in 1971
Electronics companies
Norwegian companies established in 1971 | Power (company) | [
"Engineering"
] | 65 | [
"Electronics companies",
"Engineering companies"
] |
74,451,504 | https://en.wikipedia.org/wiki/Conformal%20linear%20transformation | A conformal linear transformation, also called a homogeneous similarity transformation or homogeneous similitude, is a similarity transformation of a Euclidean or pseudo-Euclidean vector space which fixes the origin. It can be written as the composition of an orthogonal transformation (an origin-preserving rigid transformation) with a uniform scaling (dilation). All similarity transformations (which globally preserve the shape but not necessarily the size of geometric figures) are also conformal (locally preserve shape). Similarity transformations which fix the origin also preserve scalar–vector multiplication and vector addition, making them linear transformations.
Every origin-fixing reflection or dilation is a conformal linear transformation, as is any composition of these basic transformations, including rotations and improper rotations and most generally similarity transformations. However, shear transformations and non-uniform scaling are not. Conformal linear transformations come in two types, proper transformations preserve the orientation of the space whereas improper transformations reverse it.
As linear transformations, conformal linear transformations are representable by matrices once the vector space has been given a basis, composing with each-other and transforming vectors by matrix multiplication. The Lie group of these transformations has been called the conformal orthogonal group, the conformal linear transformation group or the homogeneous similtude group.
Alternatively any conformal linear transformation can be represented as a versor (geometric product of vectors); every versor and its negative represent the same transformation, so the versor group (also called the Lipschitz group) is a double cover of the conformal orthogonal group.
Conformal linear transformations are a special type of Möbius transformations (conformal transformations mapping circles to circles); the conformal orthogonal group is a subgroup of the conformal group.
General properties
Across all dimensions, a conformal linear transformation has the following properties:
Distance ratios are preserved by the transformation.
Given an orthonormal basis, a matrix representing the transformation must have each column the same magnitude and each pair of columns must be orthogonal.
The transformation is conformal (angle preserving); in particular orthogonal vectors remain orthogonal after applying the transformation.
The transformation maps concentric -spheres to concentric -spheres for every (circles to circles, spheres to spheres, etc.). In particular, -spheres centered at the origin are mapped to -spheres centered at the origin.
By the Cartan–Dieudonné theorem, every orthogonal transformation in an -dimensional space can be expressed as some composition of up to reflections. Therefore, every conformal linear transformation can be expressed as the composition of up to reflections and a dilation. Because every reflection across a hyperplane reverses the orientation of a pseudo-Euclidean space, the composition of any even number of reflections and a dilation by a positive real number is a proper conformal linear transformation, and the composition of any odd number of reflections and a dilation is an improper conformal linear transformation.
Two dimensions
In the Euclidean vector plane, an improper conformal linear transformation is a reflection across a line through the origin composed with a positive dilation. Given an orthonormal basis, it can be represented by a matrix of the form
A proper conformal linear transformation is a rotation about the origin composed with a positive dilation. It can be represented by a matrix of the form
Alternately a proper conformal linear transformation can be represented by a complex number of the form
Practical applications
When composing multiple linear transformations, it is possible to create a shear/skew by composing a parent transform with a non-uniform scale, and a child transform with a rotation. Therefore, in situations where shear/skew is not allowed, transformation matrices must also have uniform scale in order to prevent a shear/skew from appearing as the result of composition. This implies conformal linear transformations are required to prevent shear/skew when composing multiple transformations.
In physics simulations, a sphere (or circle, hypersphere, etc.) is often defined by a point and a radius. Checking if a point overlaps the sphere can therefore be performed by using a distance check to the center. With a rotation or flip/reflection, the sphere is symmetric and invariant, therefore the same check works. With a uniform scale, only the radius needs to be changed. However, with a non-uniform scale or shear/skew, the sphere becomes "distorted" into an ellipsoid, therefore the distance check algorithm does not work correctly anymore.
References
Abstract algebra
Functions and mappings
Transformation (function)
Conformal mappings | Conformal linear transformation | [
"Mathematics"
] | 907 | [
"Mathematical analysis",
"Functions and mappings",
"Transformation (function)",
"Mathematical objects",
"Linear operators",
"Mathematical relations",
"Geometry",
"Abstract algebra",
"Algebra"
] |
74,452,071 | https://en.wikipedia.org/wiki/C%20ya%20laterrrr | c ya laterrrr is an autobiographical hypertext fiction written by Dan Hett about his experiences following his brother dying in the Manchester Arena bombing. It won the New Media Writing Prize in 2020.
Plot and structure
c ya laterrrr is a text-only game or hypertext fiction written in Twine. The story is written in the second person, following the convention of interactive fiction. While the game has only one endpoint, the player is faced with many choices along the way and "one of the many possible pathways does reflect [Hett's] actual experience". Unlike many other Twine games, it doesn't feature back/next buttons, forcing the player to stick with the choices they make. Hett has emphasised the importance of these choices in interviews, saying that c ya laterrrr is "as much about what I didn't do as what I did do".
The game begins with the player as a parent in a quiet house, after their children are asleep, who sees social media posts speculating about something happening in the city. When they check their phone the next morning, they have received hundreds of messages overnight from people trying to contact them about their brother, and they learn the event in the city was a bombing at the concent their brother was attending.
Reception
Keza MacDonald, writing in The Guardian, said c ya laterrrr's "intimacy comes from its interactivity". Gabrielle de la Puente described the writing as "hard and sober and it captured the very strange lucidity that comes with waking grief".
The work won the New Media Writing Prize in 2020 and was part of the "Digital Storytelling" exhibition at the British Library in 2023. Hett has written two other works about his grief at the loss of his brother, including The Loss Levels.
Publicity around c ya laterrrr resulted in apologies to Hett from some of the reporters that approached him so soon after the tragedy.
External links
c y laterrrr on Itch.io
References
2010s electronic literature works
New media
2010s interactive fiction
British literature
Works about terrorism
Twine games
2017 video games
Video games developed in the United Kingdom | C ya laterrrr | [
"Technology"
] | 438 | [
"Multimedia",
"New media"
] |
77,363,089 | https://en.wikipedia.org/wiki/National%20Library%20Symbol | The National Library Symbol is a pictogram indicating the location of a library. It features a white silhouette of a book and a reader on a blue background (originally specified Pantone PMS #285). It was adopted by the American Library Association in 1982 to raise awareness of services provided by libraries and to convey a more "modern" image.
History
The 1979 White House Conference on Library and Information Services recommended the adoption of a national library symbol to increase public awareness of libraries. In 1981, American Library Association President Elizabeth W. Stone established a task force, headed by Dorothy Pollet Gray of the Library Congress, to select a symbol. After examining international examples of library symbols, the task force selected a symbol designed by Ralph E. DeVore for the Western Maryland Public Libraries in 1978. It first appeared officially in the 1982 American Library Association publication A Sign System for Libraries, which was the result of a project by Mary S. Mallery and Ralph E. DeVore to develop a standardized system of signs, color codes, and terminology for the Western Maryland Public Libraries.
At the 1982 American Library Association Annual Conference in Philadelphia, the symbol was officially endorsed for nationwide use. As criteria in its decision, the task force noted its clean and simple design, evoking that of existing international symbols, and its potential to accommodate future adaptations and modifications. The symbol was widely promoted during National Library Week, held April 17–23, 1983.
In March 1985, the Federal Highway Administration adopted the symbol for use in the 4th edition of the Manual on Uniform Traffic Control Devices (sign designation I4-1 in the 11th edition).
Adaptations
In 2009, the American Library Association released an updated version of the National Library Symbol to accompany their "Libraries Connect Communities 3: Public Library Funding & Technology Access Study." The symbol was designed by Illinois graphic designed Brian Benson. It was not intended as an official replacement of the original symbol.
In 2017, Rebecca McCorkindale released a series of images based on the National Library Symbol with the phrase "Libraries Are For Everyone". She created them in collaboration with Julie Syler and Ashley Jones from the Saline County Library in Benton, Arkansas, and released them in the public domain. She has released versions in over 100 languages. LAFE signs have been adopted as interior decorations in many libraries throughout the United States.
References
Pictograms
Symbols
Library history
Library science | National Library Symbol | [
"Mathematics"
] | 481 | [
"Symbols",
"Pictograms"
] |
77,364,540 | https://en.wikipedia.org/wiki/Erika%20Podest | Erika Podest Cardoze is a Panamanian earth scientist who works at NASA's Jet Propulsion Laboratory (JPL). She held an early interest in ecological systems and technological research, going on to earn degrees in engineering and environmental fields. Joining JPL after earning a Ph.D., she has worked on multiple NASA projects, particularly those involving satellite launches and observations of Earth's ecosystems through satellite imagery, including the Soil Moisture Active Passive and NASA-ISRO Synthetic Aperture Radar satellites. She has also spent significant time giving conferences and science presentations in Panama and elsewhere in order to increase the amount of children who choose to pursue scientific study.
Childhood and education
Born in Panama to a native Panamanian mother and an Austrian watchmaker father, Podest spent her childhood developing an interest in nature and technology. Her father took her out to explore nature every weekend, including hiking and swimming and locations such as Gatun Lake and Taboga Island. She attended Embry-Riddle Aeronautical University to earn a bachelor's degree in electrical engineering, before going on to earn a master's degree in applied environmental physics with a thesis on tropical rainforest deforestation and a Ph.D. where she researched the impacts of carbon dioxide on plant growth in high elevation northern latitudes. During her latter graduate work, she started an eight-month internship with JPL in 2002 to study global ecosystems and remained working there after completing her Ph.D.
Career
Once Podest was officially hired by JPL in 2009, she was assigned to the Carbon Cycle and Ecosystems Group to use remote sensing with satellite imagery and radar to determine the effects of climate change on different ecosystems. In 2011, she began working on the Soil Moisture Active Passive satellite mission and was involved in its launch in January 2015. For the ongoing mission, she has been monitoring soil moisture with the satellite to, for one reason, see the impact of climate change on moisture levels globally. In addition, she has been using other satellite data to discover how biodiversity is being affected over time. She later was made a member of the NASA-ISRO Synthetic Aperture Radar (NISAR) mission and acts as an instructor for NASA's Applied Remote Sensing Training (ARSET) program.
To promote children's interest in science, particularly in Latin American countries such as her home, Podest has annually attended the Los Angeles "Adelante Mujer Latina" conference. She also frequently returns to Panama to do tours and presentations there on scientific topics. She presented a conference in 2016 on the subject of climate change to Panamanian government officials, local environmentalists, and a large number of students from across the country. The Panamanian government sponsored a 15-minute video production in 2020 titled "Mentes Curiosas" (Curious Minds) to air on national television and which prominently featured Podest alongside other NASA scientists. In 2023, she collaborated with the United States Embassy in Panama and the Panama American Center to promote the "NASA in Panama" initiative that involved Podest traveling to schools across Panama to promote science and space research to children.
Awards and honors
For her work, Podest was named one of the most "outstanding Panamanians in science" by the government of Panama.
References
Living people
Jet Propulsion Laboratory faculty
NASA people
21st-century Panamanian women
Panamanian women scientists
Panamanian people of Austrian descent
Environmental scientists
Women earth scientists
Year of birth missing (living people) | Erika Podest | [
"Environmental_science"
] | 687 | [
"Environmental scientists"
] |
77,364,650 | https://en.wikipedia.org/wiki/HD%201502 | HD 1502 (proper name Citadelle) is an 8th-magnitude K-type subgiant star in the constellation of Pisces, located at a distance of approximately 630 light-years. A super-Jupiter planet, HD 1502 b (proper name Indépendance), is known to orbit the star.
Nomenclature
In 2019, the Republic of Haiti was assigned to giving the HD 1502 system a proper name as part of the IAU100 NameExoWorlds Project, planned to celebrate the hundredth anniversary of the International Astronomical Union (IAU), which grants the right to name an exoplanetary system to every state and territory in the world. Names were submitted and selected within Haiti, which were then presented to the IAU to be officially recognized. On 17 December 2019, the IAU announced that HD 1502 and its planet, b, were named Citadelle and Indépendance, respectively.
Citadelle refers to the Citadelle Laferrière, a fortress located in Milot in northern Haiti, which was built in 1820 and declared a World Heritage Site in 1982 as part of the National History Park. Indépendance was named after the Haitian Declaration of Independence, in celebration of the country's independence on 1 January 1804.
Stellar characteristics
The star has evolved past the main sequence stage and is now a subgiant with a mass of 1.46 , a radius of 4.67 , and a spectral type of K0. The star is slightly richer than the Sun in elements heavier than hydrogen and helium, with a metallicity of 0.09 ± 0.03.
The star has an effective temperature of , making it cooler than the Sun (5,772 K). Despite this, its large size makes it roughly 12 times brighter. At around 3.0 billion years old, the star is about two-thirds the age of the Sun (4.6 Gyr). Due to its high mass, however, it is further evolved than the Sun, which will spend a total of 10 billion years as a main sequence star.
Planetary system
In 2011, an exoplanet orbiting HD 1502, designated HD 1502 b, was discovered using the radial-velocity method. HD 1502 b revolves around its host star at a distance of with a period of little over one year in a near-circular orbit (i.e., with a low eccentricity), similarly to planets in the Solar System. It is a super-Jupiter planet with a minimum mass of 2.75 and a predicted radius of 1.183 .
See also
List of proper names of stars
List of proper names of exoplanets
List of stars in Pisces
List of exoplanets discovered in 2011
References
Footnotes
Further reading
Citadelle
Pisces (constellation)
001502
001547
K-type subgiants
Planetary systems with one confirmed planet
Durchmusterung objects
J00191704+1403172 | HD 1502 | [
"Astronomy"
] | 610 | [
"Pisces (constellation)",
"Constellations"
] |
77,366,057 | https://en.wikipedia.org/wiki/Radiation-enhanced%20diffusion | Radiation-enhanced diffusion is a phenomenon in materials science like physics and chemistry, wherein the presence of radiation accelerates the diffusion of atoms or ions within a material. The effect arises because of the creation of defects in the crystal lattice, such as vacancies or interstitials, by the radiation.
References
Materials science | Radiation-enhanced diffusion | [
"Physics",
"Materials_science",
"Engineering"
] | 66 | [
"Applied and interdisciplinary physics",
"Materials science",
"nan"
] |
77,366,241 | https://en.wikipedia.org/wiki/Soft%20Ionization%20by%20Chemical%20Reaction%20in%20Transfer | Soft Ionization by Chemical Reaction in Transfer is a method for ionizing small organic compounds at ambient atmospheric pressure. It is used for ion generation in mass spectrometers (MS).
The technique is often abbreviated as SICRIT, a trademark of Plasmion GmbH, which commercialized the technique in the 2020s.
Ionization technique
Sicrit ionizes molecules through a technique known as dielectric barrier discharge. This process involves creating an electrical discharge between two electrodes that are separated by a dielectric. The electrodes are a stainless-steel tube placed inside a copper tube, with a thin quartz tube separating them. The sample containing the molecules to be ionized flows through the quartz tube separating the electrodes. A voltage is applied to the electrodes; the resulting electrical discharge ignites a cold plasma which ionizes the sample.
Unlike other ambient ionization methods such as DART, DAPPI or DESI, SICRIT takes place directly in line with the inlet system of the MS and thus in a continuous flow:Several reaction pathways have been identified that lead to ionization during this process:
The proton transfer via hydronium clusters, similar to spray-based methods (c. ESI).
The hydronium cluster mechanism as with chemical methods (cf. APCI).
The radical cation pathway: After an initial electron ionization of gas, solvent, and analyte, the formed radical cations are stabilized by abstraction of hydrogen atoms from other reactants, such as solvents, resulting mainly in a protonated molecule.
A reaction pathway where charge transfer occurs through reactive species and UV radiation (photoionization).
Regardless of the specific reaction pathway, almost exclusively protonated species [M+H]+ are generated during ionization.
Since the analytes do not come into direct contact with the plasma during ionization, but rather charge transfer occurs via reactive species and UV radiation, the molecules remain intact and fragmentation is avoided. Consequently, SICRIT is a very "soft" ionization method.
Characteristics
The SICRIT technology decouples sample delivery from the ionization process. Through the flow principle, the sample is directly drawn into the high vacuum behind the MS inlet and ionized on its way into the inlet. The electrode geometry is chosen so that, under the given physical parameters (pressure, ignition voltage, gas constant, see Paschen's law), flexibility regarding the plasma medium is ensured. This allows the generation of stable cold plasma even in ambient air. In the simplest application, ambient air can be directly analyzed.
Ionization in flow enables high ion transmission since ion loss is significantly reduced compared to the most commonly used spraying methods in mass spectrometry (cf. ESI, APCI). Consequently, this leads to an increase in sensitivity compared to these methods.
Ionization in flow also allows for real-time measurement without the need for sample preparation. Simple screening applications, especially for volatile organic compound analysis, can be easily implemented since the usual sample preparation (including crushing, extraction, purification, etc.) becomes obsolete for simple screening applications.
The different reaction pathways in plasma ionization broaden the spectrum of ionizable substances. This means that compared to ionization methods that only allow for single reaction pathways, a wider polarity range of analytes is covered, and nonpolar substances such as hexane can be ionized.
The low fragmentation ionization allows for identification based on the molecular mass as protonated [M+H]+ species. This can be particularly useful in combination with high-resolution mass spectrometers such as time-of-flight mass spectrometers (TOF-MS) or Orbitrap-MS for non-target analysis, where the entire substance spectrum of a sample is captured based on the exact mass of the molecules.
Thus, SICRIT can be used in combination with both liquid chromatography (LC) as well as gas chromatography (GC). This enables the performance of both LC-MS and GC-MS analyses on the same mass spectrometer and the establishment of a unified database for comparing data from these otherwise instrumentally separated separation and detection methods.
Instruments and application
Direct screening
As ambient ionization, SICRIT technology enables direct, real-time gas phase measurement using a mass spectrometer. The sample is positioned directly in front of the SICRIT source without any preparation. One application area is the measurement of aromatic compounds.
Chromatography couplings
The SICRIT ion source allows for coupling with various types of chromatography (GC, HPLC, SFC, etc.) as interface technology to any atmospheric pressure mass spectrometer (LC-MS). The ionization with its characteristics (see above) is not influenced by the coupling, allowing the same ionization method to be used for different chromatography couplings. The ability to couple gas chromatography with a low-fragmentation ionization technique on an LC-MS, for example, can be utilized in the analysis of saturated hydrocarbons. Electron impact ionization commonly used in GC-MS leads to difficult-to-interpret fragmentation spectra, while plasma ionization provides fragmentation-free spectra. Thus, the DBD plasma with its broad ionization range opens up new fields of application possibilities for LC mass spectrometers in residue analysis, such as pesticides, where gas chromatographic separation is the method of choice and plasma ionization achieves very low detection limits.
Chemical imaging
In combination with appropriate sample preparation and instrumentation, the SICRIT ion source can also be used for imaging mass spectrometry. The standard procedure typically involves elaborate sample preparation combined with laser desorption/ionization (e.g., MALDI or atmospheric pressure MALDI), allowing spatial visualization of biomolecules, for example, in tissue sections.
The use of the SICRIT source for additional in-line post-ionization in AP-MALDI experiments can result in significant signal enhancement in the detection of metabolites in biological sample material or enables detection of small (bio)molecules that are not addressable using MALDI alone.
Furthermore, the SICRIT ion source enables spatially resolved analysis of unprepared samples in laser ablation experiments (cf. Fig. 3). The analytes released by laser bombardment are ionized directly with the SICRIT ion source, and the spatially resolved data are translated into two-dimensional images. This provides information, for example, on the distribution of active ingredients in tablets.
Cell analysis
In combination with a flow cytometer, the SICRIT ion source also enables the analysis of individual cells. The separated cell is introduced into the mass spectrometer through the ion source, and the lysate released upon cell rupture is analyzed. More precisely, the molecules contained in the lysate (mostly lipids) are ionized.
References
Ionization | Soft Ionization by Chemical Reaction in Transfer | [
"Physics",
"Chemistry"
] | 1,412 | [
"Ionization",
"Physical phenomena"
] |
77,366,328 | https://en.wikipedia.org/wiki/Infostealer | In computing, infostealers are a form of malicious software created to breach computer systems to steal sensitive informationincluding login details, financial information, and other personally identifiable information. The stolen information is then packaged, sent to the attacker, and often traded on illicit markets to other cybercriminals.
Infostealers usually consist of a bot framework that allows the attacker to configure the behaviour of the infostealer, and a management panel that takes the form of a server to which the infostealer sends data. Infostealers infiltrate devices through phishing attacks, infected websites, and malicious software downloads, including video game mods and pirated software, among other methods. Once downloaded, the infostealers gather sensitive information about the user's device and send the data back to the server.
Infostealers are usually distributed under the malware-as-a-service (MaaS) model, where developers allow other parties to use their infostealers for subscription fees. The functionality of infostealers can vary, with some focused on data harvesting, while others offer remote access that allows additional malware to be executed. Stolen data may then be used in spearphishing campaigns for other cyber-attacks, such as the deployment of ransomware.
The number of stolen data logs being sold on the Russian Market, a cybercrime forum, has increased significantly since 2022. According to Kaspersky's research in mid-2023, 24% of malware offered as a service are infostealers.
Overview
In cybercrime, credential theft is a well-known mechanism through which malicious individuals steal personal information such as usernames, passwords, or cookies to illegitimately gain access to a victim's online accounts and computer. This crime typically unfolds in four stages, with the first being the acquisition of the stolen credentials. Infostealers are a specific type of malware that are designed for this initial stage. They usually consist of two distinct parts: the bot framework and a command and control server, often known as the management panel or interface.
The bot framework includes a builder that allows the attacker to configure how the infostealer will behave on a user's computer and what kind of information it will steal. The management interface, usually written in traditional web development languages like PHP, HTML, and JavaScript, is typically hosted on the commercial cloud infrastructure. The management interface primarily functions as a web server to which the infostealer sends confidential information. The interface also provides the attacker with information about the status of deployed infostealers and allows the attacker to control their behaviour.
Distribution and use
Infostealers are commonly distributed through the malware-as-a-service (MaaS) model, enabling individuals with varying technical knowledge to deploy these malicious programs. Under this model, three distinct groups typically emerge: developers, malware service providers, and operators. Developers, the most technically skilled, write the infostealer code. Malware service providers purchase licenses for the malware and offer it as a service to other cybercriminals. The operators, who can be developers or service providers themselves depending on their skill level, use these services to perform credential theft.
Once the malware is purchased, it is spread to target victim machines using various social engineering techniques. Phishing, including spear phishing campaigns that target specific victims, is commonly employed. Infostealers are commonly embedded in email attachments or malicious links that link to websites performing drive-by downloads. Additionally, they are often bundled with compromised or malicious browser extensions, infected game cheating packages, and pirated or otherwise compromised software. After the stealer is downloaded and run by a victim, it communicates with the attacker's command-and-control servers, allowing the attacker to steal information from the user's computer. While most infostealers primarily target credentials, some also enable attackers to remotely introduce and execute other malware, such as ransomware, on the victim's computer.
Credentials obtained from infostealer attacks are often distributed as logs or credential dumps, typically shared on paste sites like Pastebin, where cybercriminals may offer free samples, or sold in bulk on underground hacking forums, often for amounts as low as $10. Buyers of these stolen credentials usually log in to assess their value, particularly looking for credentials associated with financial services or linked to other credentials with similar patterns, as these are especially valuable. High-value credentials are often sold to other cybercriminals at higher prices, who may then use them for various crimes, including financial fraud, integrating the credentials into zombie networks and reputation-boosting operations, or as springboards for more sophisticated attacks such as scamming businesses, distributing ransomware, or conducting state-sponsored espionage. Additionally, some cybercriminals use stolen credentials for social engineering attacks, impersonating the original owner to claim they have been a victim of a crime and soliciting money from the victim's contacts. Many buyers of these stolen credentials take precautions to maintain access for longer periods, such as changing passwords and using Tor networks to obscure their locations, which helps avoid detection by services that might otherwise identify and shut down the stolen credentials.
Features
An infostealer's primary function is to exfiltrate sensitive information about the victim to an attacker's command-and-control servers. The exact type of data that is exfiltrated will depend on the data-stealing features enabled by the operator and the specific variant of infostealer used. Most infostealers, however, do contain functionality to harvest a variety of information about the host operating system, as well as system settings and user profiles. Some more advanced infostealers include the capability to introduce secondary malware like remote access trojans and ransomware.
In 2009, researchers at the Symantec Rapid Response team released a technical analysis of the Zeus infostealer, one of the first infostealers to be created. They found that the malware automatically exfiltrated all data stored in a computer's protected storage service (which was usually used by Internet Explorer to store passwords) and tries to capture any passwords sent to the computer using the POP3 and FTP protocols. In addition to this, the malware allowed the researchers to define a set of configuration files to specify a list of web injections to perform on a user's computer as well as another configuration file that controlled which web URLs the malware would monitor. Another configuration also allowed the researchers to define a set of rules that could be used to test if additional HTTP requests contained passwords or other sensitive information.
More recently, in 2020, researchers at the Eindhoven University of Technology conducted a study analysing the information available for sale on the underground credential black market impaas.ru. As part of their study, they were able to replicate the workings of a version of the AZORult infostealer. Amongst the functions discovered by the researchers was a builder, which allowed operators to define what kind of data would be stolen. The researchers also found evidence of plugins that stole a user's browsing history, a customisable regex-based mechanism that allows the attacker to retrieve arbitrary files from a user's computer, a browser password extractor module, a module to extract Skype history, and a module to find and exfiltrate cryptocurrency wallet files.
The researchers also found that the data most frequently stolen using the AZORult infostealers and sold on the black market could be broadly categorised into three main types: fingerprints, cookies, and resources. Fingerprints consisted of identifiers that were constructed by probing a variety of features made available by the browser. These were not tied to a specific service but were considered to be an accurately unique identifier for a user's browsers. Cookies allowed buyers to hijack a victim's browser session by injecting it into a browser environment. Resources refer to browser-related files found on a user's operating system, such as password storage files.
Economics and impact
Setting up an infostealer operation has become increasingly accessible due to the proliferation of stealer-as-a-service enterprises, significantly lowering financial and technical barriers. This makes it feasible for even less sophisticated cybercriminals to engage in such activities. In a 2023 paper, researchers from the Georgia Institute of Technology noted that the hosted stealer market is extremely mature and highly competitive, with some operators offering to set up infostealers for as low as $12. For the service providers running these stealer operations, the researchers estimated that a typical infostealer operator incurs only a few one-off costs: the license to use the infostealer, which is obtained from a malware developer, and the registration fee for the domain used to host the command-and-control server. The primary ongoing cost incurred by these operators is the cost associated with hosting the servers. Based on these calculations, the researchers concluded that the stealer-as-a-service business model is extremely profitable, with many operators achieving profit margins of over 90% with revenues in the high thousands.
Due to their extreme profitability and accessibility, the number of cybersecurity incidents that involve infostealers has risen. The COVID-19 post-pandemic shift towards remote and hybrid work, where companies give employees access to enterprise services on their home machines, has also been cited as one of the reasons behind the increase in the effectiveness of infostealers. In 2023, research by Secureworks discovered that the number of infostealer logsdata exfiltrated from each computerbeing sold on the Russian market, the biggest underground market, increased from 2 million to 5 million logs from June 2022 to February 2023. According to Kaspersky's research in mid-2023, 24% of malware offered as a service are infostealers.
References
Citations
Sources
Security breaches
Cybercrime
Types of malware
Malware by type
Social engineering (security)
Cyberwarfare | Infostealer | [
"Technology"
] | 2,105 | [
"Malware",
"Computer security exploits"
] |
77,366,958 | https://en.wikipedia.org/wiki/Flore%20laurentienne | Flore laurentienne (The Laurentian Flora En) by Marie-Victorin Bro. (Conrad Kirouac), is the scientific inventory of vascular plant resources growing spontaneously in the St. Lawrence River valley, in Quebec, Canada.
First published by the Bros. of the Christian Schools in 1935, the manual lists and describes 1568 species of Pteridophytes, Gymnosperms, Angiosperms, plants illustrated by Bro. Alexandre Blouin.
History
The Flore laurentienne is the fruit of thirty years of study, research, gathering, plant collecting, and classification of thousands of specimens. In 1935, in the midst of an economic crisis, it took the energy, charisma and sense of organization of Marie-Victorin, assisted by his collaborators, to bring the manuscript to the presses of the Brothers of the Christian Schools.
From its launch on April 3, 1935, at the Viger Hotel in Montreal, the Flore laurentienne was acclaimed as the bible of French-Canadian naturalists.
Flore laurentienne divisions
<blockquote>Preface — Historical and bibliographical summary of Laurentian botany — General outline — Synopsis of systematic groups — Artificial key to plants of Quebec — Pteridophytes — Spermatophytes — Gymnosperms — Angiosperms — Dicotyls — Monocotyls — Glossary — Abbreviations of author names — Alphabetical index (Marie-Victorin, p. 4, 1935)</blockquote>
Editions
Recent publications are still available in bookstores, educational institutions, public libraries and on line, the work published for the first time in 1935, in large format, has undergone several reissues:
Second edition, completely revised and updated by Ernest Rouleau (1916-1991), published in September 1964, printed on Bible paper and in a reduced format;
Third edition, updated and annotated by Luc Brouillet, Stuart G. Hay and Isabelle Goulet, published in October 1995, reprinted in 2002;
Digital edition, florelaurentienne.com, on line, updated, annotated, continuously active since 2001.
Collaborators
To carry out his work, Bro. Marie-Victorin surrounded himself with several collaborators, some of whom were his students. At the forefront of these is Bro. Alexandre [Blouin] (1892-1987), the author of the 2800 illustrations of the Flora, and whose name appears on the title page of the work. Jacques Rousseau, who would later become a botanist and ethnologist of international reputation is the author of the " artificial key of Quebec plants ”, which, by avoiding overly technical elements and using the simplest and easiest to perceive characters, « allows even beginners and amateurs to orient themselves and arrive at the desired identification ». For his part, Jules Brunel, Marie-Victorin's assistant at the Montreal Botanical Institute, was responsible for preparing the manuscripts, checking the documentation and correcting the proofs. The last two mentioned also wrote the sections dealing with some of the more contentious genres.
The author also addresses special thanks to other people, including Bro. Rolland-Germain, his collaborator for thirty years, Marcelle Gauvreau, librarian of the Botanical Institute, and Émile Jacques, curator of the herbarium of this institution.
Reception
... The publication of the first edition of Flore laurentienne was an event awaited by Quebec society at the time; it is announced on the front page of the daily Le Devoir. Biologist Georges Préfontaine wrote in Le Devoir: “A new monument, luminous and imperishable, stands today in the firmament of American botanical science.” The literary critic Pierre Daviault, in Le Droit, is equally complimentary:
The same year the flora was published, the gold medal from the Provancher Society of Natural History of Canada was awarded to Marie-Victorin for its publication.
Culture
The Flore laurentienne is mentioned several times in Réjean Ducharme's novel, L’Hiver de force''.
References
External links
Archive | Brother Marie-Victorin: a heritage between nature and literature, quotes, analyses, audio documents, Radio-Canada Info, July 2019
Frère Marie-Victorin (1885-1944), Anticosti, land with immense spaces, the sea all around, and a social world of the 1920s gone forever. Anticosti/UdeM archives, 14 photos (French)
Marie-Victorin Herbarium, Institut de recherche en biologie vegetale, at the Montreal Botanical Garden
Revisit the Laurentian Flora, Michaële Perron-Langlais, Radio-Canada, 12 June 2024
.
.
Florae (publication)
Flora of Quebec | Flore laurentienne | [
"Biology"
] | 983 | [
"Flora",
"Florae (publication)"
] |
77,367,858 | https://en.wikipedia.org/wiki/Completions%20in%20category%20theory | In category theory, a branch of mathematics, there are several ways (completions) to enlarge a given category in a way somehow analogous to a completion in topology. These are: (ignoring the set-theoretic matters for simplicity),
free cocompletion, free completion. These are obtained by freely adding colimits or limits. Explicitly, the free cocompletion of a category C is the Yoneda embedding of C into the category of presheaves on C. The free completion of C is the free cocompletion of the opposite of C.
ind-completion. This is obtained by freely adding filtered colimits.
Cauchy completion of a category C is roughly the closure of C in some ambient category so that all functors preserve limits. For example, if a metric space is viewed as an enriched category (see generalized metric space), then the Cauchy completion of it coincides with the usual completion of the space.
Isbell completion (also called reflexive completion), introduced by Isbell in 1960, is in short the fixed-point category of the Isbell conjugacy adjunction. It should not be confused with the Isbell envelope, which was also introduced by Isbell.
Karoubi envelope or idempotent completion of a category C is (roughly) the universal enlargement of C so that every idempotent is a split idempotent.
Exact completion
Notes
References
Further reading
https://mathoverflow.net/questions/59291/completion-of-a-category
Category theory | Completions in category theory | [
"Mathematics"
] | 328 | [
"Functions and mappings",
"Mathematical structures",
"Mathematical objects",
"Fields of abstract algebra",
"Category theory",
"Mathematical relations"
] |
77,368,450 | https://en.wikipedia.org/wiki/Arcs%20%28board%20game%29 | Arcs: Conflict & Collapse in the Reach is a space opera board game designed by Cole Wehrle, illustrated by Kyle Ferrin, and published by Leder Games in 2024 alongside Arcs: The Blighted Reach Expansion, a large expansion which significantly modifies the base game into a three-act legacy campaign. In Arcs, players compete to gain the most points by fulfilling variable objectives, taking actions through a trick-taking system and using different dice to attack enemy starships, with each player possessing variable powers. Following initial releases to Kickstarter backers, the base game and expansion were released to retail on October 1 2024.
Gameplay
The base game of Arcs is a fast-paced strategy game set in the "Reach", an area of outer space. Players portray spacefaring societies, and attempt to win by obtaining galactic supremacy, gaining points by fulfilling various objectives called "ambitions", which include constructing buildings, upgrading their respective spaceships, gathering resources from the various planets depicted on the board, and waging war. Each game is played over five "chapters", or rounds, and begins with a randomized setup.
A large amount of gameplay revolves around trick-taking using action cards. This begins each round with one player, who has the 'initiative', leading by placing a card onto the table from their hand and taking actions based on the card's suit, and other players following based on the number on that card, sometimes being restricted into copying the same action as a result. Some cards allow more actions to be taken, with a base number of 1 actions per turn and extra actions allowed if resources, which are also used to score points, are spent. The player who leads is able to declare an ambition, determining how players score points in that round, but in doing so drops the number on their played card to zero, meaning that others can easily overtake them in the turn order. Available court cards enable players to customise their personal gameplay through individual powers, and can be stolen by other players.
Players fight with starship pieces which can be in three states; healthy, damaged or off the board, effectively allowing them two points of damage. Three types of dice are used for different types of attack on the board, with blue dice offering low damage but no risk, red dice being more aggressive but coming with significant risk, and orange dice which enable the theft of resources but at a high risk. The attacking player can choose to distribute damage among their own ships while concentrating damage on individual enemy ships, thus encouraging players to play aggressively.
The Blighted Reach Expansion
Arcs: The Blighted Reach Expansion is a day-one expansion of the base game which turns it into a three-session campaign with changing rules. At the beginning of the campaign, players are given a choice between two "fates", some of which introduce new systems to the game which affect all players and which can change between each game of the campaign if that player chooses to do so. The board state is retained between each game in the campaign.
Development
Wehrle has stated that after the completion of the design of his 2021 game Oath: Chronicles of Empire and Exile, he "was filled with all sorts of odd ideas that didn't fit into that game", and "wanted to stay in the space but design something new," making a more "narratively chunky" game. He was inspired by roguelike games.
Initially marketed during development as Arcs: Collapse and Conflict in the Void, the game was announced on October 3, 2021. At this point, Wehrle described it as a "short campaign game" playable in 2 to 4 sessions for 3 to 4 players and with a total run time of five hours maximum. In February 2022, Wehrle stated that the game would have "40 to 50" different objective cards to pursue, leading to "tens of thousands of different possible game states", including secret objectives, with the result of each game having a direct impact on the setup of the next.
On May 3, 2022, A Kickstarter campaign was scheduled for May 24 until June 14 that year, with shipment to backers estimated to begin in December 2023. Unlike Wehrle's 2018 game Root, players of Arcs were expected to have starting identities rather than asymmetric factions, and unlike Oath, the game world would be reset after three games of the campaign.
On May 17, 2022, Leder Games announced that it planned to separate the campaign section of Arcs from its replayable base game, instead marketing the campaign as an expansion; Wehrle cited potential future struggles in marketing Arcs as a big-box experience, as well as the need to provide an "arcade mode" for players to understand the game better before beginning an "overwhelming" campaign as the main reasons for this change. In doing this, the game could also be designed with the intention to add further expansions in the form of add-on modules by their other designers. He designed the campaign expansion as a "three-act structure", in which the acts were individual playthroughs that each flowed into the next game through analog "procedural generation". Wehrle intended for the game to operate in a similar way to games such as Twilight Imperium and Eclipse, though with significantly quicker games of 60-90 minutes.
The Kickstarter campaign earned over $532,000 in its first five hours when launched. In March 2023, while Arcs was in its early access development stage, Wehrle stated that the game would feature a two-player mode, requiring a restriction of the size of the map, alteration of how cards were drawn and change to how players gained resources and scored points. The game's full retail release was expected in September 2024, though it was eventually released on October 1 that year.
Reception
Arcs received high praise from critics. Rob Wieland of Forbes praised the game for its speed compared to Twilight Imperium, Eclipse and Star Wars: Rebellion. He remarked that the base game was "one that's stayed in the conversation with my friends long after we’ve tried it out," and compared the start of each game to "a Star Wars cold open", with players feeling as though they were "the head of a big space bureaucracy". Bell of Lost Souls compared the game to "if Warhammer 40,000 stopped pretending it wasn't as goofy and silly as it is" and called it a "space opera". In July 2024, Luis Aguasvivas of NPR listed Arcs as one of the best games of the year thus far. Polygon awarded it the Polygon Recommends badge, stating that its expansion was "completely over the top in all the best ways, and there’s nothing yet released quite like it", and it was "a magnificent design that deserves recognition as one of 2024’s best releases." Matt Thrower of IGN gave the game a 10/10 "masterpiece" rating, writing that the game was successful in its attempt to "balance challenging strategic elements with the classic fun of negotiation and dice-rolling", and that it was "an awesome thing to behold, carving a story arc of its own right through the annals of board game design".
See also
Root, Pax Pamir, John Company and Oath: Chronicles of Empire and Exile, other board games designed by Wehrle.
References
External links
Arcs page on the Leder Games website
American board games
Asymmetric board games
Science fiction board wargames
Kickstarter-funded tabletop games
Legacy games | Arcs (board game) | [
"Physics"
] | 1,545 | [
"Asymmetric board games",
"Symmetry",
"Asymmetry"
] |
77,370,485 | https://en.wikipedia.org/wiki/Organismal%20performance | Organismal performance (or whole-organism performance) refers to the ability of an organism to conduct a task when maximally motivated.
Various aspects of performance are of primary concern in human athletics, horse racing, and dog racing. Performance in swimming tasks has been a subject of fisheries research since the 1960s. In a broader biological context, the term first came to prominence with studies of locomotor abilities in lizards and snakes in the late 1970s and early 1980s.
Paradigm
A seminal paper by Stevan J. Arnold in 1983
focused on the importance of performance as an intermediary between lower-level traits and how natural selection acts. In particular, selection should act more directly on performance than on the subordinate traits (e.g., aspects of morphology, physiology, neurobiology) that determine performance abilities. In other words, how fast a lizard can run is more important in escaping from predators than are the lengths of its legs, because they only party determine its ability to run fast. Since then, others have pointed out that behavior often acts as a "filter" between selection and performance
because animals do not always behave in ways that use their maximal performance abilities. For example, if a lizard that saw a predator approaching did not choose to run, then its ability to sprint would be irrelevant. In any case, the original version of the conceptual model has stimulated much research in integrative organismal biology. However, contrary to the hypothesis that selection should be stronger on whole-organism functional performance traits (such as sprinting ability) than on correlated morphological traits, a review of empirical studies did not find evidence that selection measured in the wild was stronger on performance.
In plants
Although organismal performance is more commonly studied in animals (including human beings) than in plants, various studies have focused on whole-plant performance in a similar vein. For example, suction feeding abilities have been measured in carnivorous plants (bladderworts). Although plants do not have either a nervous system or muscles, they can be said to have behavior.
How such "behavior" may serve as a filter between performance and selection apparently has not been studied.
See also
References
Behavior
Evolutionary biology
Physiology | Organismal performance | [
"Biology"
] | 436 | [
"Evolutionary biology",
"Behavior",
"Physiology"
] |
77,371,207 | https://en.wikipedia.org/wiki/Mahi%20R.%20Singh | Mahi R. Singh (b. 1949) is a professor of physics at Western University researching nanoscience. He was awarded the Fulbright US-Canada Research Chair for 2021-2022.
Early life
Singh was born in 1949 in Hamirpur, India. He received his B.Sc. degree in T.D. College campus; and both M.Sc. (1970) and PhD (1976) degrees from Banaras Hindu University in condensed matter physics.
Academic career
Singh was awarded Humbold Fellow in Stuttgart University from 1979 to 1981. Between 1981 and 1985 he was a Research Associate and Lecturer at McGill University. From 1982 to 1983 he worked in High Magnetic Field Lab, Université Paul Sabatier as a visiting scientist. He also worked as Research Associate at University of North Carolina.
He joined the University of Western Ontario as associate professor in 1985. Currently he is professor in this university. He was also a visiting professor at Texas Center for Superconductivity from June till November in 1992. He also worked as a chief researcher at Superconductors Division of Hitachi, Tokyo between November 1992. During May and August in 2022, he became Fulbright US-Canada Research Chair in Vanderbilt University.
His visiting positions include Texas Center for Superconductivity (1992), University of Oxford (1993-1994), and Dubna and Ioffe Institute Saint Petersburg (2019).
Research
Research topics include:
Nanomaterials and Nanocomposites
Nanophotonics, Plasmonics, and Polaritonics
Graphene and Carbon Nanostructures
Metallic Nanostructures
Second Harmonic Generation
Photonic
Metamaterials
Biomaterials
Selected honors and awards
NIST Visiting Researcher, NIST USA, 2022
Fulbright US-Canada Research Chair, 2020-2021
External Expert for Gerhard Herzberg Canada Gold Medal for Science and Engineering, 2020-2021
Royal Society Visiting Scientist/Professor. 1993-1994
Chief Researcher, Hitachi, Tokyo in 1992–1993
Alexander von Humboldt Award, 1979
References
1949 births
Living people
Canadian physicists
Western University of Health Sciences
Banaras Hindu University alumni
Indian physicists
McGill University
University of North Carolina | Mahi R. Singh | [
"Materials_science"
] | 441 | [
"Metamaterials scientists",
"Metamaterials"
] |
77,371,428 | https://en.wikipedia.org/wiki/Valeri%20Frolov%20%28physicist%29 | Valeri Frolov (born October 7, 1946) is a Russian-born Canadian theoretical physicist at the University of Alberta, Canada.
Education
Valeri Frolov is a theoretical physicist specializing in the study of black holes. He was born and grew up in Moscow. He graduated from the Moscow State University and obtained his Master’s Degree in 1970. He received his first PhD degree (“Candidate of Sciences”) in 1973 and his second Doctor Degree (“Doctor of Sciences”) in 1980, both from P.N. Lebedev Physical Institute, Moscow, in theoretical physics.
Work
His professional scientific career started in 1970 when he jointed the P.N. Lebedev Physical Institute. He was working there as an assistant professor, an associate professor, and a full professor (after 1980) until 1992. During the period 1985-1992 he was also a professor at the Moscow Institute of Physics and Technology (MIPT). During 1992-1993 he spent one year as a visiting professor in the University of Copenhagen. In 1993 he moved to Edmonton, Canada where he became a full professor at the University of Alberta and received a Killam Memorial Chair position. He is working at this position till now.
Research
Early in his career, Frolov studied white holes and semi-closed worlds. In 1970 he with his supervisor M.A. Markov published a paper where quantum particle creation by charged black holes was discussed. In 1980 he (with Gregory Vilkovisky) proposed a model of a regular evaporating black hole and presented a conformal diagram of its spacetime. Later his main interest focused on quantum effects in black hole. In 1987 he with Vitaly Ginzburg published a paper on the equivalence principle in quantum domain. In 1989 he with Kip Thorne published a paper discussing quantum effects near the horizon of a rotating black hole and proposed a state of the vacuum, which sometimes is refereed as the Frolov-Thorne vacuum. In 1994 he (with A. Barvinsky and A. Zelnikov) introduced a no-boundary wave function of a black hole and in 1996 he with (D. Fursaev and A. Zelnikov) proposed explanation of the black hole entropy based on Sakharov’s ideas of induced gravity. During the same period of time, he also studied cosmic strings (their interaction with black holes and quantum effects in the string background), wormholes and “time machines”, and regular black hole models. During the period 2006-2018 the main focus of his research was on hidden symmetries of four and higher dimension black holes. In collaboration with D. Kubiznak and P. Ktrous he demonstrated that all these solutions of the Einstein equations possessed a special geometrical object, called Killing-Yano tensor, which is responsible for a complete integrability of equations of motion of particles and separability of most interesting physical field equations in these spacetimes. More recently, he proposed an effective action for electromagnetic and gravitational spin-optics which is a generalization of the standard geometric optics and takes into account the interaction of the spin of these fields with the spacetime curvature.
Awards and honors
Killam Memorial Chair (from 1993 till now)
In 2016, Markov Prize of INR of Russian Academy of Sciences for outstanding contribution to the black hole theory.
Books
Igor D. Novikov and Valeri P. Frolov, “Black Hole Physics” (Fundamental Theories of Physics, Volume 27, 341 pages, 1989. This is an English translation of the book in Russian, published in 1986 by Nauka Publ.
Valeri P. Frolov and Igor D. Novikov, “Black Hole Physics: Basic Concepts and New Developments”, Fundamental Theories of Physics, Volume 96, 770 pages, 1998
Valeri P. Frolov and Andrei Zelnikov, “Introduction to Black Hole Physics”, Oxford University Press, 488 pages, 2011
Book chapter
Frolov, V. P. The Newman-Penrose Method in the Theory of General Relativity. A chapter in: Basov, N.G. (eds) Problems in the General Theory of Relativity and Theory of Group Representations. The Lebedev Physics Institute Series. Springer, Boston, MA., pages 73–185, 1979
References
External links
Valeri Frolov at Google Scholar
1946 births
Living people
Theoretical physicists
Moscow State University alumni
University of Alberta
People from Moscow
Moscow Institute of Physics and Technology | Valeri Frolov (physicist) | [
"Physics"
] | 913 | [
"Theoretical physics",
"Theoretical physicists"
] |
77,371,664 | https://en.wikipedia.org/wiki/Neuroinclusive%20design | Neuroinclusive design or neuro-inclusive design is a human-centered approach of designing products, services, or environments in a way that enables individuals of all sensory profiles to coexist within the same space. Neuroinclusive design create spaces and experiences that are accessible and user-friendly for everyone covering the entire "neurodiversity" spectrum.
A key criticism in Human-Computer Interaction (HCI) is that research often excludes neurodivergent people from being actively involved in the design process. Instead of highlighting their strengths and unique experiences, the technologies typically focus on perceived deficits and behaviors deemed disruptive by normal standards. Consequently, the outcomes overlook the emotional and practical needs of neurodivergent users and perpetuate harmful stereotypes and stigmas.
Further reading
References
Neurodiversity
Design | Neuroinclusive design | [
"Engineering"
] | 171 | [
"Design stubs",
"Design"
] |
77,371,778 | https://en.wikipedia.org/wiki/NGC%207726 | NGC 7726 is a large barred spiral galaxy located in the constellation Pegasus in the northern sky. It is estimated to be 348 million light-years from the Milky Way and about 150,000 light-years in diameter. Many other objects are located within a close proximity to NGC 7726, including NGC 7720, NGC 7728, IC 5341 and IC 5342.
The object was discovered by astronomer Lewis Swift on August 8, 1886.
See also
List of NGC objects (7001–7840)
References
Barred spiral galaxies
Pegasus (constellation)
7726
12721
72024 | NGC 7726 | [
"Astronomy"
] | 119 | [
"Pegasus (constellation)",
"Constellations"
] |
77,371,907 | https://en.wikipedia.org/wiki/Caloboletus%20conifericola | Caloboletus conifericola, commonly known as the dark bitter bolete, is a species of mushroom in the family Boletaceae. It is found in the Pacific Northwest.
Taxonomy
Caloboletus conifericola was first described by Alfredo Vizzini in 2014.
Description
The cap of Caloboletus conifericola is grayish-brown to olive gray and about 3-10 inches (7-25 cm) across. The stipe is about 2-10 inches (5-15 cm) long and about 1-2 inches wide at the top. It starts out wider at the base, but more or less evens out as the mushroom grows older. The pore surface is yellow, and the mushroom oxidizes blue when bruised.
Similar species
Caloboletus conifericola can be confused with Caloboletus calopus and Caloboletus frustuosus. Caloboletus calopus has a more reticulated stipe than C. conifericola, and C. frustulosus has a more cracked cap.
Habitat and ecology
Caloboletus conifericola is found in moss and leaf litter under conifer trees, especially grand fir and western hemlock. It is found fruiting during early fall, soon after the rains come.
See also
List of North American Boletes
References
marshii
Fungus species
Inedible fungi
Fungi of North America
Fungi described in the 21st century | Caloboletus conifericola | [
"Biology"
] | 298 | [
"Fungi",
"Fungus species"
] |
77,372,003 | https://en.wikipedia.org/wiki/Terzan%20Catalogue | The Terzan Catalogue (abbreviation: Ter) is an astronomical catalogue of globular clusters.
Overview
The Terzan Catalogue consists of 11 globular clusters discovered by Agop Terzan using infrared observations made at Lyon Observatory in France during the 1960s and early 1970s. Most of the globular clusters are located in the constellations of Sagittarius and Scorpius, near the Milky Way's Galactic Center; Terzan 7 and Terzan 8 are most likely part of the Sagittarius Dwarf Elliptical Galaxy. Although all of the Terzan Catalogue objects were originally presumed to be globular clusters, there have been recent suggestions (by Mikkel Steine and others) that some of them may in fact be open clusters.
Since the original Terzan 11 is a duplicate of Terzan 5, more recent versions of the catalogue have renamed the original Terzan 12 as Terzan 11.
The catalogue is based on scientific papers published by Agop Terzan in 1966 (for Terzan 1), 1967 (for Terzan 2), 1968 (for Terzan 3 to 8), and 1971 (for Terzan 9 to 12).
List of clusters
List of star clusters in the Terzan Catalogue:
See also
List of astronomical catalogues
List of globular clusters
References
Astronomical catalogues | Terzan Catalogue | [
"Astronomy"
] | 266 | [
"Astronomical catalogues",
"Astronomical objects",
"Works about astronomy"
] |
77,372,038 | https://en.wikipedia.org/wiki/NGC%201175 | NGC 1175, also known as the Peanut Galaxy, is a large lenticular galaxy located in the constellation Perseus. Its speed relative to the cosmic microwave background is 5,349 ± 19 km/s, which corresponds to a Hubble distance of 78.9 ± 5.5 Mpc (∼257 million ly). It was discovered by the German-British astronomer William Herschel in 1786.
NGC 1175 is about the same distance from the Milky Way as NGC 1177. These two galaxies form a gravitationally interacting pair.
To date, a non-redshift measurement gives a distance of approximately 44,900 Mpc (∼146 million ly). This value is far outside the Hubble distance values. Note that it is with the average value of independent measurements, when they exist, that the NASA/IPAC database calculates the diameter of a galaxy.
See also
List of galaxies
List of NGC objects (1001–2000)
External links
NGC 1175 at NASA/IPAC
NGC 1175 at SIMBAD
NGC 1175 at SEDS
NGC 1175 at LEDA
References
Lenticular galaxies
Perseus (constellation)
Discoveries by William Herschel
1175
02515
11578 | NGC 1175 | [
"Astronomy"
] | 247 | [
"Perseus (constellation)",
"Constellations"
] |
77,372,761 | https://en.wikipedia.org/wiki/Rhodosporidiobolus%20fluvialis | Rhodosporidiobolus fluvialis is a species of fungus in the family Sporidiobolaceae. It is a human fungal pathogen that exhibits resistance to antifungal compounds like fluconazole and caspofungin.
Antifungal resistance
Rhodosporidiobolus fluvialis was isolated from two independent patients. It can proliferate well at , a temperature similar to the human body's internal temperature. When it is incubated at , reactive oxygen species accumulate and damage its DNA, which causes mutations that lead to the development of resistance to amphotericin-B.
R. fluvialis colonies can be pigmented due to the accumulation of carotenoids in the cells. Carotenoid production has been associated with its resistance to caspofungin.
References
Sporidiobolales
Fungus species
Fungi described in 1988
Fungal pathogens of humans | Rhodosporidiobolus fluvialis | [
"Biology"
] | 190 | [
"Fungi",
"Fungus species"
] |
77,373,411 | https://en.wikipedia.org/wiki/Samsung%20Galaxy%20Watch%207 | The Samsung Galaxy Watch 7 (stylized as Samsung Galaxy Watch7) is a series of Wear OS-based smartwatches developed by Samsung Electronics. It was announced on July 10, 2024, at Samsung's biannual Galaxy Unpacked event. The watches were launched on July 24, 2024.
Specifications
References
External links
Consumer electronics brands
Products introduced in 2024
Smartwatches
Samsung wearable devices
Watch 7
Wear OS devices | Samsung Galaxy Watch 7 | [
"Technology"
] | 89 | [
"Wear OS devices",
"Smartwatches"
] |
78,813,563 | https://en.wikipedia.org/wiki/Weather%20of%202025 | The following is a list of weather events that occurred on Earth in the year 2025. These are several weather events which had a significant impact were blizzards, cold waves, droughts, heat waves, wildfires, floods, tornadoes, and tropical cyclones.
Deadliest events
Types
The following listed different types of special weather conditions worldwide.
Cold snaps and winter storms
January 20–22, 2025 Gulf Coast blizzard
Heat waves and droughts
Tornadoes
Tropical and subtropical cyclones
Extratropical cyclones and European windstorms
Wildfires
The January 2025 Southern California wildfires are a series of ongoing wildfires in California, mostly around the Los Angeles area, that have so far caused at least 24 deaths and destroyed or damaged at least 12,401 structures.
Timeline
This is a timeline of weather events during 2025.
January
See also
Weather of 2024
Weather of 2023
Weather of 2022
Weather of 2021
References
External links
Weather by year
Weather-related lists
2025-related lists
2025 meteorology | Weather of 2025 | [
"Physics"
] | 198 | [
"Weather",
"Physical phenomena",
"Weather by year",
"Weather-related lists"
] |
78,813,714 | https://en.wikipedia.org/wiki/Titanium%20tetraazide | Titanium tetraazide is an inorganic chemical compound with the formula . It is a highly sensitive explosive, and has been prepared from titanium tetrafluoride and trimethylsilyl azide via the corresponding fluoride-azide exchange.
Properties
Titanium tetraazide has been characterized by vibrational spectroscopy and single-crystal X-ray diffraction. The compound was predicted in 2003 to be vibrationally stable, and was expected to have a tetrahedral structures containing linear bond angles, contrasting other metal azides which generally feature bent bond angles. After synthesis in 2004, the resulting titanium tetraazide did not exhibit linear bond angles, as the coordination numbers exceeded 4.
References
azide
titanium | Titanium tetraazide | [
"Chemistry"
] | 146 | [
"Explosive chemicals",
"Azides",
"Inorganic compounds",
"Inorganic compound stubs"
] |
78,813,845 | https://en.wikipedia.org/wiki/Fumarprotocetraric%20acid | Fumarprotocetraric acid is a chemical compound with the chemical formula . It is a secondary metabolite produced by a variety of lichens.
Occurence
Fumarprotocetraric acid is mainly known for its occurrence in Iceland moss (Cetraria islandica), where it is present in a mass fraction of 1–2% (dried thallus).
In addition, fumarprotocetraric acid has been detected in many other lichens, including:
Callopisma teicholytum []
Cetraria fahluensis []
Cetraria islandica []
Cladina rangiferina []
Cladina silvatica []
Cladonia chlorophaea []
Cladonia fimbriata [] var. apolepta [] f. coniocraea []
Cladonia fimbriata [] var. cornuto-radiata []
Cladonia fimbriata [] var. simplex [] f. major []
Cladonia fimbriata [] var. simplex [] f. minor []
Cladonia foliacea [] var. alcicornis []
Cladonia foliacea [] var. convoluta []
Cladonia furcata [] var. pinnata []
Cladonia furcata [] var. racemosa []
Cladonia gracilis [] var. chordalis []
Cladonia gracilis [] var. elongata []
Cladonia pityrea [] var. cladomorpha []
Cladonia pityrea [] var. Zwackhii []
Cladonia pyxidata [] var. cereina []
Cladonia pyxidata [] var. neglecta []
Cladonia subcervicornis []
Cladonia verticillata [] var. cervicornis [] f. phyllophora [() ]
Cladonia verticillata [] var. evoluta []
Dendrographa leucophaea []
Parmelia stygia [() ]
Pharmacology research
Fumarprotocetraric acid has antibacterial activity. It also induces an immunostimulating effect in vitro by triggering the formation of hydrogen peroxide. Furthermore, cytotoxicity against two cancer cell lines has been demonstrated.
References
Dicarboxylic acids
Benzaldehydes
Hydroxyarenes
Lichen products
Benzoic acids
Fumarate esters
Benzodioxepines | Fumarprotocetraric acid | [
"Chemistry"
] | 543 | [
"Natural products",
"Lichen products"
] |
78,814,861 | https://en.wikipedia.org/wiki/Enzomenib | Enzomenib is an investigational new drug that is being evaluated for the treatment of acute leukemia. It is a small molecule inhibitor that targets the interaction between menin and mixed-lineage leukemia (MLL) proteins. Enzomenib particularly in patients with KMT2A (MLL) rearrangements or NPM1 mutations.
The U.S. Food and Drug Administration (FDA) has granted both Fast Track and Orphan Drug designations to Enzomenib.
References
Alkenes
Antineoplastic drugs
Azetidines
Benzamides
Carboxamides
Ethers
Fluorobenzenes
Isopropylamino compounds
Piperidines
Pyrimidines
Spiro compounds | Enzomenib | [
"Chemistry"
] | 141 | [
"Pharmacology",
"Functional groups",
"Medicinal chemistry stubs",
"Organic compounds",
"Alkenes",
"Ethers",
"Pharmacology stubs",
"Spiro compounds"
] |
78,815,001 | https://en.wikipedia.org/wiki/Epsametostat | Epsametostat is an investigational new drug that is being evaluated for the treatment of peripheral T-cell lymphoma. It is a EZH1/EZH2 inhibitor developed by Shanghai Haihe Pharmaceutical Research & Development Co., Ltd.
References
Antineoplastic drugs
Alkyl groups
Amides
2-Pyridones
Indolizines
Methoxy compounds
Piperazines
Pyridazines
Trifluoromethyl compounds | Epsametostat | [
"Chemistry"
] | 95 | [
"Pharmacology",
"Substituents",
"Alkyl groups",
"Functional groups",
"Medicinal chemistry stubs",
"Pharmacology stubs",
"Amides"
] |
78,816,401 | https://en.wikipedia.org/wiki/Speca | Speca, discovered in 2011, is an exotic radio galaxy or a galaxy where the central supermassive black hole is actively accreting matter surrounding itself and ejects two giant, million light year long, plasma lobes in opposite directions.Speca is located around 1.9 billion light-years away in the constellation Virgo.
Discovery and significance
Speca was discovered by an international team of astronomers led by Dr Ananda Hota, using archival data from Sloan Digital Sky Survey (SDSS), Very Large Array and observations from the Giant Meterwave Radio Telescope. Where almost all radio galaxies are hosted by massive, featureless, elliptical galaxies, Speca is the first confirmed exception that such giant plasma lobes can also be hosted by spiral galaxies. This confirmation came after 12 long years of the first suspected case ESO 0313-192. Speca was a convincing case because it has two, and possibly three, episodes of such plasma lobe emission and rotation of the spiral galaxy, fast and flat, is clearly observed.
Soon after this, search for Speca-like exotic objects were intensified, and in the next 12 years the total number increased to close to three dozen. Due to its exotic nature, some have started calling it Spiral DRAGNs, despite the word DRAGNs not used commonly for radio galaxies. The growing list can be found here List of Spiral DRAGNs. Since such galaxies are rarely seen in nearby Universe and elliptical galaxies were yet to form in the formative era of our Universe, it has been speculated that, Speca-like radio galaxies hosted in giant spirals may be more common in the young Universe. Future observations with giant optical telescopes (e.g. Thirty Metre telescope, Extremely Large Telescope ) combined with sensitive observations with low frequency radio telescopes ( e.g. LOFAR, Giant Meterwave Radio Telescope and Square Kilometre Array Observatory ) may find many of them to understand galaxy evolution better.
References
Radio galaxies | Speca | [
"Astronomy"
] | 391 | [
"Virgo (constellation)",
"Constellations"
] |
78,817,781 | https://en.wikipedia.org/wiki/Micropollutant | Micropollutants are substances that even at very low concentrations have adverse effects on different environmental matrices. They are an inhomogeneous group of atroprogenic chemical compounds that is discharged by human to the environment. Commonly known micropollutants that might pose possible threats to ecological environments are, to name just a few:
environmental persistent pharmaceutical pollutants and personal care products,
pesticides,
stimulants,
persistent organic pollutants,
and artificial sweeteners
To date, most of the scientists have identified wastewater treatment plants as the main source of micropollutants to aquatic ecosystems and/or adversely affect the extraction of potable water from raw water. Due to in many places drinking water is also extracted from surface waters, or the substances also reach the groundwater via the water, they are also found in raw water and must be laboriously removed by drinking water treatment. In addition, some of the substances are bioaccumulative, which means that they accumulate in animals or plants and thus also in the human food chain.
Background
It is estimated that there are currently around 235,000 individual chemical substances registered worldwide. A large number of these are released into wastewater by humans. If these are persistent, they remain during clarification in the wastewater and enter the environment. Some of them have ecotoxic relevant properties. In some cases, the chemical itself is not a concern, but its degradation products are.
This has been known for a longer time. As early as 1976, a study was published in which salicylic acid and clofibric acid were detected in the effluent of a sewage treatment plant in Kansas City. We currently know that there are well over 1,000 substances in wastewater that pose a risk. Many others have not yet been sufficiently researched in this regard.
In current studies of water quality in European rivers by the Helmholtz Centre for Environmental Research, 610 chemicals whose occurrence or problematic effects are known were examined in more detail and analyzed to determine whether and, if so, in what concentrations they occur in Europe's flowing waters. The evaluation of 445 samples from a total of 22 rivers showed that the researchers were able to detect a total of 504 of the 610 chemicals. In total, they found 229 pesticides and biocides, 175 pharmaceutical chemicals as well as surfactants, plastic and rubber additives, per- and polyfluoroalkyl substances (PFAS) and corrosion inhibitors. In 40 percent of the samples they detected up to 50 chemical substances, in another 41 percent between 51 and 100 chemicals. In 4 samples they were even able to detect more than 200 organic micropollutants. With 241 chemicals, they detected the most substances in a water sample from the Danube.
Effect
The influences of micropollutants are varied. The best known are those of hormones that enter the water through the contraceptive pill. Several studies have shown that feminization occurs in an unusually high number of fish below discharges from sewage treatment plants, which has a negative impact on the population. One in five male smallmouth bass in U.S. rivers has developed female sexual characteristics. Estrogen-like artificial compounds such as the plasticizer bisphenol A also have this effect. There is evidence that this also applies to humans. Such substances are called endocrine disruptors. Other substances, such as benzotriazole, which is added to dishwasher detergent as corrosion protection for silver cutlery, are suspected of being carcinogenic in addition to acting as an endocrine disruptor in the concentrations found.
Another relevant factor is the danger posed by the spread of multi-resistant bacteria. There are two possible ways in which this can happen through wastewater. Firstly, by transporting already resistant strains into the receiving water due to inadequate treatment technology. The other possibility is the development of resistant cultures in the environment by introducing antibiotics into the water body. Preventing the entry of bacteria has long been used as a form of hygienic treatment using UV light or ozone, especially if the water is to be reused. Membrane systems such as membrane bioreactors or downstream ultrafiltration also serve this purpose. Depending on the intensity and technology, some micropollutants are also removed in addition to the bacteria. The extent to which membrane technologies with low energy consumption are able to deplete trace substances is being investigated.
Legislation
Techniques for elimination of micropollutants via a so called fourth treatment stage during sewage treatment are implemented in Germany, Switzerland, Sweden and the Netherlands and tests are ongoing in several other countries. In Switzerland it has been enshrined in law since 2016.
Since 1 January 2025, there has been a recast of the Urban Waste Water Treatment Directive in the European Union, which requires the removal of a large proportion of micropollutants from wastewater. Due to the large number of amendments that have now been made, the directive was rewritten on November 27, 2024 as Directive (EU) 2024/3019, published in the EU Official Journal on December 12, and entered into force on January 1, 2025. The member states now have 31 months, i.e. until July 31, 2027, to adapt their national legislation to the new directive ("implementation of the directive").
The implementation of the framework guidelines is staggered until 2045, depending on the size of the sewage treatment plant and its population equivalents (PE). Sewage treatment plants with over 150,000 PE have priority and should be adapted immediately, as a significant proportion of the pollution comes from them followed by wastewater treatment plants with 10,000 to 150,000 PE that discharge into coastal waters or sensitive waters. The latter concerns waters with a low dilution ratio, waters from which drinking water is obtained and those that are coastal waters, or those used as bathing waters or used for mussel farming. Member States will be given the option not to apply fourth treatment in these areas if a risk assessment shows that there is no potential risk from micropollutants to human health and/or the environment.
Removal of micropollutants
Due to the large number of substances with very different chemical and physical properties, the removal of these substances is difficult.
Three techniques and cominationes of them have been established so far.
Two remove the contaminants with the help of activated carbon (PAC (Powdered Activated Carbon), GAC (Granulated Activated Carbon)) and one with ozone.
In addition to that a large number of techniques are still in experimental stage. These include for example processes that work with plasma or ultrasound, so-called AOP processes, applications with zeolites and cyclodextrins, membrane processes or photocatalysis.
See also
Drug pollution
Plastic particle water pollution
Environmental impact of silver nanoparticles
Environmental persistent pharmaceutical pollutant
Water pollution
References
Pollution
Environmental science
Water pollution
Environmental impact of products
Medical waste
Environmental microbiology
Toxicants
Environmental ethics
Environment and health
Environmental issues | Micropollutant | [
"Physics",
"Chemistry",
"Biology",
"Environmental_science"
] | 1,430 | [
"Toxicology",
"Environmental ethics",
"Medical waste",
"Harmful chemical substances",
"Water pollution",
"Materials",
"Toxicants",
"nan",
"Environmental microbiology",
"Matter"
] |
78,817,856 | https://en.wikipedia.org/wiki/Chromium%28III%29%20selenide | Chromium(III) selenide is an inorganic chemical compound with the formula . It is one of the several chromium-selenium phases, along with CrSe. It is formed as a maroon-colored amorphous powder, and has a rhombohedral crystal structure.
Properties
Sheets of chromium(III) selenide were found to contain ferromagnetic properties, when below 70K.
References
Chromium(III) compounds
Selenides | Chromium(III) selenide | [
"Chemistry"
] | 102 | [
"Inorganic compounds",
"Inorganic compound stubs"
] |
78,818,209 | https://en.wikipedia.org/wiki/HD%20166191 | HD 166191 is a young late-F or early G-type star in the constellation Sagittarius. It is surrounded by a large amount of dust. In 2019 it was reported in the Astronomer's Telegram that the star had brightened in the infrared, as was seen from Spitzer observations. A study was published in 2022, reporting on the result of a follow-up campaign. This study showed that a dust cloud as large as the star did transit in front of it. This cloud was produced from a giant collision between two planetesimals.
In early works the age of the system was not certain and ranged between 10-100 Myrs. The large amount of dust was interpreted as being produced by a recent collision of planetary embryos or by massive ongoing collisional grinding. A later work did determine a younger age. The star was observed with ground-based spectroscopy and with Herschel. The researchers did find that the star is surrounded by a protoplanetary disk with a hole in the center. The silicate feature was also determined to be similar to primordial object. This would make the disk a so-called transitional disk, meaning it lies in between protoplanetary and debris disk. Observations with the Submillimeter Array did however find a high amount of dust and only little amount of gas, indicating that the disk is a debris disk. Another work determined that the disk is made up of two debris belts. An inner belt at ∼0.27 AU with a temperature of about 760 Kelvin (K) and an outer belt at ∼5 AU with a temperature of about 175 K.
It was suggested that HD 166191 co-moves with HD 163296. This was questioned in a later work.
2018-2019 collision event
Follow-up observations of the 2018-2019 brightening event were carried out with Spitzer, ASAS-SN and the Hereford Arizona Observatory. The disk has become brighter in the infrared since early 2018, reaching a maximum in mid 2019. ASAS-SN observed a dip during the infrared brightening. 142 ±0.3 days later the second dip was seen with both Spitzer and ASAS-SN, having a depth of ≳80% in the optical. The new dust from the collision was at first compact, having a size of 1 stellar diameter vertically and about 2–3 stellar diameters horizontally. After two orbital periods the clump grew larger, but also optical thinner and no further dips could be observed. The researchers find a semi-major axis of 0.62 AU for a circular orbit, but the researchers also point out that the orbit is likely eccentric. The collision released dust with a minimum mass of ~1–4 × 1023 g. The researchers think that a collision occurred between two large bodies with a sizes of ≳500 km (larger than 4 Vesta). The event set off a chain reaction of impacts between the fragments of the first collision and other small bodies in the system.
See also
List of extrasolar planetary collisions
List of stars that have unusual dimming periods
2MASS J08090250-4858172
Giant impact hypothesis
References
Circumstellar disks
Impact events
F-type main-sequence stars
Sagittarius (constellation)
166191 | HD 166191 | [
"Astronomy"
] | 663 | [
"Astronomical events",
"Impact events",
"Sagittarius (constellation)",
"Constellations"
] |
78,818,646 | https://en.wikipedia.org/wiki/SN%201999em | SN 1999em was a well-observed type II-P supernova in the spiral galaxy NGC 1637, which lies within the mostly southern constellation of Eridanus. It was discovered on October 29, 1999 at a visual magnitude of 13.3. Using a corrected version of the expanding photosphere method (EPM), the distance to the supernova is estimated as . This is in good agreement with the Cepheid method, which yields a distance of .
Observations
This supernova event was first detected by the Lick Observatory Supernova Search from a CCD frame taken October 29, 1999 with the Katzman Automatic Imaging Telescope (KAIT). The discovery was confirmed by the Beijing Astronomical Observatory the same day. It showed an apparent visual magnitude of 13.5. A KAIT image of the same area taken October 20th showed nothing at the position of this supernova. SN 1999em was positioned west and south of the NGC 1637 nucleus. A spectrum taken October 30 showed this to be a type II supernova event. The early expansion velocity of the photosphere was measured at . Interstellar lines in the spectrum indicated the event may be partially obscured by dust.
X-ray emission was detected from this source on November 1–2 and 11–12 using the Chandra X-ray Observatory. The number of photons detected suggested a luminosity of for the source. A compact radio source at this position was detected on December 1 from the NRAO Very Large Array. This was the first type II-p supernova to be detected at both X-ray and radio wavelengths. By now the target was identified as a type II-P supernova, based on the shape of the light curves and spectral properties. Spectrapolarimetry measured between November 1999 and January 2000 showed an increasing level of polarization at later dates. This implied asphericity toward the core of the explosion – meaning a deviation from spherical symmetry.
Photometric observations showed that SN 1999em remained in its plateau phase for approximately 90 days, indicating that the progenitor possessed a massive hydrogen envelope when the explosion occurred. The explosion date was estimated to be before discovery. By day 161, the spectrum was dominated by emission lines, indicating that the remnant was transitioning to the nebular phase. Evidence showed that dust formation began at around day 500. The exponential decay rate of the light curve tail was mainly powered by the radioactive decay of 56Co to 56Fe. Ejecta mass is estimated at approximately and the surviving neutron star has .
The host galaxy is close enough that individual bright supergiants can be resolved. However, no such object was detected at the position of the event. Supernova models indicate a progenitor mass in the range of , with near solar metallicity and an explosive energy of . This star had a radius of about . Radio and X-ray emission indicate the progenitor was surrounded by clumpy or filamentary circumstellar material that was fed by a low stellar mass loss rate of about ·yr−1 with a wind velocity of . The light curve for this event is nearly identical to that of SN 1999gi, suggesting they may have similar progenitor stars.
References
Further reading
Supernovae
Eridanus (constellation) | SN 1999em | [
"Chemistry",
"Astronomy"
] | 666 | [
"Supernovae",
"Astronomical events",
"Constellations",
"Explosions",
"Eridanus (constellation)"
] |
78,819,121 | https://en.wikipedia.org/wiki/Chiodectonic%20acid | Chiodectonic acid is an organic compound in the structural class of chemicals known as anthraquinones. It occurs as a secondary metabolite in some lichens.
History
The red pigment "pyxiferin" was first isolated from the lichen Pyxine coccifera by K. Chandrasenan and colleagues in 1965, who proposed a biphenylquinone structure for it. Later, during research on chiodectonic acid, Wolfgang Steglich noticed that this pigment shared the same Rf value in thin-layer chromatography (TLC) as chiodectonic acid from Chiodecton sanguineum. Though initial investigation was limited by the small amount of lichen material available, subsequent analysis of a larger quantity of P. coccifera confirmed that "pyxiferin" was actually identical to chiodectonic acid. Since chiodectonic acid had been previously described by Oswald Hesse in 1904, this name takes precedence. Further analysis showed that the compound from both lichens had the molecular formula C15H10O8, contradicting the C13H8O8 formula that Chandrasenan et al. had reported for pyxiferin.
Properties
Chiodectonic acid is a member of the class of chemical compounds called anthraquinones. Specifically, it is a naphthoquinone derivative. Its IUPAC name is 2-acetyl-3,5,6,8-tetrahydroxy-7-methoxybenzo[f][1]benzofuran-4,9-dione. The ultraviolet absorbance maxima (λmax) has three peaks at 287, 510, and 538 nm. In the infrared spectrum, peaks occur at 736, 800, 816, 828, 854, 944, 970, 1008, 1042, 1076, 1120, 1176, 1290, 1410, 1456, 1534, 1590, 1624, 1658, 3000, and 3340 cm−1. Chiodectonic acid's molecular formula is C15H10O8; it has a molecular mass of
334.23 grams per mole. In its purified form, it exists as dark red rhombic plates with a melting point of .
References
Lichen products
Naphthoquinones
Acetyl compounds
Naphthofurans | Chiodectonic acid | [
"Chemistry"
] | 495 | [
"Natural products",
"Lichen products"
] |
78,819,327 | https://en.wikipedia.org/wiki/Antonietta%20Gonsalvus | Antonietta (Tognina) Gonsalvus, also Gonzalves or Conzales (born around 1572–1580 in France) was a so-called monkey girl. She became famous for suffering (like her father and three of her five brothers) from hypertrichosis (a congenital disease). Her family is considered to be the oldest case of human excessive hair growth described in Europe. Antonietta's death year is not known but she supposedly died in Capodimonte (Viterbo), Italy, where her father also died.
Life and family
Antonietta has been depicted in various paintings and prints both as a little girl and as a young woman and has become known under the name Tognina. She grew up in Fontainebleau and was part of the court of King Henry II of France and his wife, Catherine de Medici de Valois. Tognina is mentioned primarily in reports about her family, some of whom like her, suffered from hypertrichosis, also called Ambras syndrome.
Tognina's father, Petrus Gonsalvus, was born in Tenerife, Canary Islands, in 1556. As a child, he was sent to the court of Henry II where he was initially kept as a monkey and didn't receive attention as a human until he grew up. Petrus, who was eventually educated and learned to speak Latin, married a beautiful woman, Catherine Raffelin from Paris who did not have abnormal body hair.
The couple had several children, some of whom, including Tognina, inherited their father's illness and others who did not. King Henry gave the Gonsalvus family a part of the vast park at his Palace of Fontainebleau to give them a natural environment and protection. Petrus, called the "ape-man," regularly participated in social events, dressed in courtly robes, while little Tognina always dressed like a doll. The Gonsalvus family is known to have traveled to Italy around 1580–1590 as their stay was recorded at the court of Margaret of Parma.
Scientific inquiries
The family's excessive hairiness attracted the interest of scholars. The Italian doctor and naturalist Ulisse Aldrovandi (1522–1605) reported in detail about the family in his book, Monstrorum Historia, published in 1642, and mentioned Ambras in Tyrol as their place of residence. In the local castle, Archduke Ferdinand II of Tyrol and Rudolf II had set up an art and curiosity chamber that included a huge collection of curiosities, which also housed a painting of the Gonsalvus family, made by Rudolf II's court painter, the Antwerp miniaturist Georg Hoefnagel. That painter mentioned the family as a special "species of animal" in a sketchbook for the Animalia Rationalia et Insecta.
Italian painter Lavinia Fontana made a famous portrait of little Tognina holding a letter that tells the story of the child's family."Don Pietro, a savage discovered on the Canary Islands, was shipped to his Serene Highness Henri King of France and from there to his Excellency the Duke of Parma. I, Antonietta, was born from him and today I can be found at the Court of Dame Isabella Pallavicina, the Honorable Marquise of Soragna.”
Other references
In 2016, Tognina's portrait was used in a horror video game called Layers of Fear and represents a character nicknamed ‘Babyface.’
Literature
Hans Scheugl: Show Freaks & Monster. Felix Adanos Collection. DuMont Buchverlag: Cologne, 1978; p. 33ff. with illustrations
Roberto Zapperi: The wild man of Tenerife. The miraculous story of Pedro Gonzalez and his children. Munich, CH Beck 2004, ISBN 978-3-406-44792-1
References
16th-century French women
Hair diseases
Hair
Congenital disorders
Fontainebleau | Antonietta Gonsalvus | [
"Biology"
] | 811 | [
"Organ systems",
"Hair"
] |
78,819,364 | https://en.wikipedia.org/wiki/AN/ALR-46 | AN/ALR-46 is a radar warning receiver (RWR) that processes received signals from up to 16 hostile radar emitters in the 218 GHz frequency range to determine threats to the aircraft. Originally manufactured by Litton Industries and General Instruments, Dalmo-Victor division (now Northrop Grumman), it has been used on several U.S. Air Force aircraft including the A-7D Corsair, B-52 Stratofortress, C-130 Hercules, F-4 Phantom II, F-104 Starfighter, F-105 Thunderchief, F-111 Aardvark and RF-4 Phantom II and others.
History
The first battlefield operational testing of the ALR-46 occurred in August 1972 when a team of Dalmo-Victor and Warner Robins engineers installed the system on F-104G aircraft dubbed "Wild Weasels". Flight testing took place against threats in the Suez Canal area and Egypt. By January 1973, the system had proven reliable and accurate enough to be deployed to an F-105G in Southeast Asia (SEA).
In accordance with the Joint Electronics Type Designation System (JETDS), the "AN/ALR-46" designation represents the 46th design of an Army-Navy electronic device for passive countermeasures signal receiver. The JETDS system also now is used to name all Department of Defense electronic systems.
In 1999, the Situational Awareness Defensive Initiative (SADI) program was created to significantly upgrade the ALR-46. The program was valued at $48 million in 2000, and was expected to run through 2003. Improving situational awareness was the "highest priority modification needed for the B-52".
Technical description
Features
The ALR-46 receiver set allows aircrew to detect the presence of up to 16 threat radars and identify certain characteristics of those radars.
Components
4 Amplifier/Detectors
Signal processor
Indicator control
Azimuth indicator
See also
List of military electronics of the United States
References
External links
GlobalSecurity.org - B-52 specifications
Electronic warfare equipment
Military electronics of the United States
Equipment of the United States Air Force
Electronic countermeasures
Military equipment introduced in the 1970s
Radar warning receivers
Radiofrequency receivers | AN/ALR-46 | [
"Technology"
] | 455 | [
"Warning systems",
"Radar warning receivers"
] |
78,819,438 | https://en.wikipedia.org/wiki/TOI-2109 | TOI-2109 is a 10.2 magnitude star in the Hercules constellation. It is located at from Earth based on parallax measurements. This star is host to one confirmed exoplanet.
Characteristics
TOI-2109 is a F-type main-sequence star, a star moderately larger, hotter and more luminous than the Sun that is fusing atoms of hydrogen into helium at its core. It is 1.7 times larger than the Sun, comparable to Sirius A, 1.4 times more massive and nearly five times brighter. The effective temperature of its surface lies at , which is 10% hotter than the Sun, whose temperature measures . Its age is uncertain, between one and 2.5 billion years. The rotation period of this star is about the same as Earth's orbital period, but only about 1/25 that of the Sun.
Planetary system
TOI-2109 hosts at least one exoplanet, which is named TOI-2109 b and was discovered in 2021 via the transit method.
TOI-2109 b is a hot Jupiter, with the shortest orbital period of its class. It completes an orbit in just , being separated by only from its host. This is the shortest period among hot Jupiters, a class of which this planet is part. The extreme proximity also means TOI-2109 b is strongly irradiated. The dayside temperature measures , while the nightside is around 1,000 degrees cooler, at less than . Only 55 Cancri e and KELT-9b have hotter dayside temperatures. This planet is around 30% larger than Jupiter and five times more massive. Its orbit is well-aligned to the star's axis.
In 2024, low-amplitude transit-timing variations were detected using the CHEOPS space telescope, which could be attributed to a yet unseen exoplanet. This putative planet should have an orbital period greater than 1.125 days and its other characteristics remain unconstrained.
Notes
References
F-type main-sequence stars
Planetary systems with one confirmed planet
Hercules (constellation)
Durchmusterung objects
TIC objects
2MASS objects | TOI-2109 | [
"Astronomy"
] | 441 | [
"Hercules (constellation)",
"Constellations"
] |
78,819,589 | https://en.wikipedia.org/wiki/Copper%28II%29%20selenide | Copper(II) selenide is an inorganic binary compound between copper and selenium, with the chemical formula CuSe.
Uses
Copper(II) selenide is produced in situ to form a protective black coating on iron or steel parts in some cold-bluing processes. Bluing solutions that operate in this manner will typically be labeled as containing selenous acid or selenium dioxide. It has also been investigated for use in the treatment of colon cancer.
Natural occurrences
Copper selenides are the most common selenium minerals. CuSe is known in mineralogy as klockmannite.
See also
Copper(I) selenide
Gallium(II) selenide
Indium(III) selenide
Copper indium gallium selenide
Copper(II) sulfate
Selenium dioxide
Selenous acid
References
Selenides
Copper compounds | Copper(II) selenide | [
"Chemistry"
] | 177 | [
"Inorganic compounds",
"Inorganic compound stubs"
] |
78,819,724 | https://en.wikipedia.org/wiki/Journal%20of%20Big%20Data | Journal of Big Data is a scientific journal that publishes open-access original research on big data. Published by SpringerOpen since 2014, it examines data capture and storage; search, sharing, and analytics; big data technologies; data visualization; architectures for massively parallel processing; data mining tools and techniques; machine learning algorithms for big data; cloud computing platforms; distributed file systems and databases; and scalable storage systems.
All articles are included in:
ESCI
Scopus
DLBP
DOAJ
ProQuest
EBSCO Discover Service
References
External links
Official website
Academic journals established in 2014
Big data
Computer science journals | Journal of Big Data | [
"Technology"
] | 124 | [
"Data",
"Big data"
] |
78,819,741 | https://en.wikipedia.org/wiki/Architecture%20in%20Trzebiat%C3%B3w | Architecture in Trzebiatów is dominated by historical forms from the Middle Ages to the early 20th century. Within the defensive walls, Trzebiatów has preserved over 50% of its historic buildings. The city features architectural elements from the Gothic, Renaissance, Baroque, Neoclassical, and Modernist periods.
Middle Ages to the Renaissance
The urban layout of Trzebiatów dates back to the granting of city rights in 1277 by Barnim I. The city was established under Lübeck law, resulting in a regular medieval town plan with a market square and a chessboard street grid. The designated area within the medieval fortifications covered 35 hectares and was divided into quarters and plots. The irregular rectangular plan, with rounded corners on the eastern side, included the site of the ducal residence and the oldest Church of St. Nicholas. Around 1285, the buildings on the hillfort were converted into a female monastery, inhabited by the Premonstratensians from the monastery in Mirosławice.
At the city's center, a market square measuring 94 by 104 meters was created, while the construction of the town's parish church was planned in the quarter to the northeast. Another small quarter near the Gryficka Gate was designated for a chapel and the Hospital of the Holy Spirit. The quarters, shaped as squares and rectangles, were formed by a regular network of 14 streets intersecting at right angles, with slight distortions in the eastern part. The plots were divided into 23 quarters.
In 1299, Trzebiatów was granted permission by Bogislaw IV to build defensive walls and moats (which were completed by 1337). The city had four gates: Kołobrzeg Gate, on the route to Kołobrzeg before the bridge over the Młyński Canal; Gryfice Gate, on the route to Gryfice; Żeglarska Gate, leading to the northwest; and Łaziebna Gate, on the way to . During the construction of the defensive walls, the digging of a wet moat began, which strengthened the city's defense system, especially on the southern, eastern, and southwest sections (near the Gryfice Gate). The fortifications were completed by 1432.
According to the cadastral map of Trzebiatów from 1730, the plots were sized at 9.50 × 36 meters, with those near the defensive walls being half the size. The wealthier citizens had access to the larger plots, while the poorer population occupied the smaller ones. In total, approximately 200 plots were designated in Trzebiatów during the medieval period, although not all were built upon. By the early 14th century, the population of the town was about 1,500 people.
The first houses were built, like in the Slavic era, from wooden beams or interlace. The buildings on the plots were constructed over a period of between 20 and 25 years. Brick houses likely began to appear only towards the end of the 14th century, due to the growing wealth of the burghers (especially merchants). Frequent fires that plagued the city are evidence of the wooden construction in Trzebiatów. The first fire broke out in 1344, destroying the mills, the monastery, and the northern part of the city, the second occurred in 1377, though there is no data on its consequences. The third fire ravaged part of the city in 1496. The first brick houses were built around the market square (however, not all houses were entirely made of brick). The brick used came from a local brickworks, which in 1307 was sold by the Premonstratensians to the town council.
The houses in Trzebiatów were built with gable ends facing the streets. The gables, with two rows of attic windows, were either triangular or stepped. The plots were developed up to about half of their length. The front part was occupied by residential houses with workshops and offices. Behind the houses were outbuildings, usually located on the left side of the yard. The yard walls and outbuildings were mostly built with the use of framing. Medieval houses were partially cellarized at the front and had wooden ceilings.
The plot sizes in the Baltic region ranged from 8 to 9 × 25 to 27 meters. Typically, 2/3 of the plot was built upon. The house had a length of 15 meters. Residential buildings were three-bay, with the main entrance in the center and two windows on the sides. The space of the entire house was filled with a lobby, with a height of 3–4 meters, only a small room (in the right corner) was built. Behind the room, which served as an office, was the kitchen, and at the yard wall, there were stairs leading to the mezzanine. In the yard wall, there was an entrance to the courtyard and to the outbuilding, where the residential part was located. In early development houses, the upper floors housed storage spaces for transport goods.
A late Gothic and early Renaissance composition with a decorated façade is the house at 27 Rynek Street, divided at the ground level by a portal and two wide windows. The gables with volute-shaped edges are accentuated by horizontal cornices. According to iconographic sources, the house at 7 Rynek Street had a very interesting Renaissance decoration, reconstructed in 1900 and recently transformed. Gothic-Renaissance forms are also found in the outbuilding walls at Głęboka and Kopernika streets. On the brick walls, there is the division of shallow blind arches, ending in segmental arches and flat lesenes dividing the smooth surfaces of the walls.
Among the most important buildings in the city at that time were the castle (now the palace), the town hall, the Church of the Blessed Virgin Mary, the Chapel and Hospital of the Holy Spirit, the Chapel and Hospital of St. George, the Chapel and Hospital of St. Gertrude, the mills, the mint, and the brickworks.
From Baroque to Neoclassicism
The oldest view of the town is featured on the vignette of the map of the Duchy of Pomerania by E. Lubinus from 1618, showing the panorama of Trzebiatów from the southeast. The dense town buildings surrounded by defensive walls, with the Kaszana Tower and the Gryficka, Kołobrzeska gates and their foregates, are visible. The city moat, central canal, and the Rega river are also marked, as well as three bridges.
Significant changes in the method of building houses occurred at the end of the 17th century when construction work in the city intensified. This was due to the destruction caused by the siege of the town and fires during the Thirty Years' War (1618–1648). Pomeranian towns, including Trzebiatów, had to endure a real plague of fires. This was reflected in the decree issued by Bogislaw XIV in 1634, ordering the construction of firewalls between buildings. In 1679, another major fire destroyed much of the town's buildings, including the town hall, monastery, and the eastern frontage of buildings along the market square (the first town hall in Trzebiatów had been built in the 15th century). The castle and several previously rebuilt houses were also destroyed. In the 1660s, renovation work was undertaken, evidenced by the opening of the "Pod Orłem" pharmacy in 1668. Around 1680, the reconstruction of the town hall began. It was designed on a rectangular plan with a courtyard in the center. A small tower with a baroque roof and a clock was placed on the roof of the building. In 1691, the reconstruction of the house at 5 Rynek Street, which housed a pharmacy (documented as early as 1596), began.
At the end of the 17th century, there were likely significant changes to the city's urban planning. The layout of plots was altered in areas where the destruction of Trzebiatów's buildings had been greatest. The highest concentration of plots was found on the eastern side of the church and along the northern stretch of the defensive walls. However, the plots along the market square remained unchanged. This is evidenced by the preserved original form of the basement walls (front and dividing walls).
According to the cadastral map of 1730, Trzebiatów had about 480 plots in the first quarter of the 18th century, numbered consecutively from 1 to 480. Only a few houses were located on plots wider than 10 m². These sources also provide information about the town's bridges. In total, there were four: one across the Rega river at the end of Głęboka Street, another across Młynówka and Rega towards the Kołobrzeska Suburb, and another one through the swamps (St. Georgen-Teich) in the area of St. George's Chapel in that suburb. According to data from 1740, Trzebiatów had a population of 2,738 people, living in around 300 houses. The rebuilding of the town made use of surviving fragments of basement walls, introducing various savings methods. The dividing walls, outbuildings, and fragments of façades were left, with the shapes of openings and especially the gables being altered, changing from triangular or stepped gables to volute-shaped ones.
The forms of windows, plastering, and façade colors were also changed. According to Z. Radacki, during the Renaissance and Baroque periods, the principle was the uniform color application of architectural details and separate backgrounds for façades. The elements of the details could be darker or lighter than the background. Renaissance townhouses were painted in vivid (intense) colors, while Baroque ones had calmer color tones.
The usable areas were increased by constructing new basements, dug underground, new courtyards, and extensions to the walls of existing basements (e.g., the house at 5 Rynek Street). Almost all basements were covered with barrel and tunnel vaults made of brick and plastered. Through expansion, the layout of interiors changed. In many houses, the hall was removed. It was divided by ceilings into two levels. Narrow, cross-cut communication paths with stairs in the central parts of buildings remained on the ground floors. Right next to the stairs were the so-called "black kitchens", small and unlit rooms with large hearths. The remaining parts of the interiors were usually divided into two sections, each containing one or more rooms.
As in the previous era, the façades of the houses on the market square were built from brick. The rear façades, partition walls, and walls of the annexes were mostly built in timber-frame construction, filled with clay. According to sources from 1720, most of Trzebiatów's buildings were constructed in timber-frame construction, but all houses were to be covered with ceramic roofing tiles by 1743. Thatched roofs were still common on the outskirts for a long time.
In 1747, another fire destroyed part of the buildings within the walls. In 1761, several houses were damaged by Russian troops due to artillery fire during the Seven Years' War. These losses were quickly recovered because the city's economic condition in the second half of the 18th century was much better than in earlier years. During this period, the city also began eliminating moats and city fortifications, transforming them into gardens. The city continued to expand its suburbs, allocating new land for plots. In the Old Town, the buildings became much denser within the plots, creating courtyard-wells. From this point on, there was a growth in population and, consequently, in the number of houses.
Houses built from scratch in the 18th century generally had from 4 to 5 axes on the façade. They were symmetrically built, with an entrance on the central axis and two windows on either side of the entrance. They were usually oriented with the gable end facing the street. They were covered with gambrel or gabled roofs. The decoration of the façades was limited to bands, shallowly profiled cornices, window and door surrounds with keys. Entrances and windows often had basket arch cutouts. Examples of preserved decorative elements can be found in houses at 18, 25, 28, 30 Rynek Street, and in houses no. from 1 to 2 on Krótka Street. Most of them were rebuilt in the 19th century, with the ground floors altered by breaking openings in the walls and creating shop windows, which led to changes in the interior appearance, shifting halls, and walls.
From the 19th to the 20th century
At the turn of the 18th and 19th centuries, Trzebiatów had a population of 3,500 living in 550 houses, including 40 in the suburbs. According to data from 1822, the population reached 4,323 people living in 676 houses, including some in suburban areas. The method of construction, including the principles of form shaping, did not change in the first half of the 19th century. No significant changes were recorded, except for minor aesthetic elements.
In 1844, the market square was adorned with a cobblestone surface, and trees were planted. The streets were lit by gas lamps, later replaced by electric ones. Street names were placed on corner plaques. The classicist architecture of the period includes the school building on Lipowa Street, constructed in 1832. Photographs of the façades of buildings along the market square from the late 19th century clearly show traditional forms. The buildings were set gable-end to the streets, with triangular gables alternating with voluted gables, and much more rarely, gables with a Gothic heritage. The houses were partly cellared, one-story, with living attics. They were often remodeled, adapting interiors for shops and services, which involved creating openings in the façades and adding storefronts and new entrances, separate from the residential ones.
In the 1840s, a new bridge was built over the Rega (the so-called "Busse Bridge") towards the Kołobrzeg Suburb. It was constructed on four oak pillars, joined by iron clamps (replacing the older arch bridge, Jachwerk, which had served for 50 years). During the construction of the cobbled road to Kołobrzeg in the 1850s, another new bridge was built (the so-called St. Georgen Bridge). Today, the bridge has been replaced by an embankment, over which the road to the Kołobrzeg Suburb now runs.
In most quarters, new buildings were erected on enlarged plots created by combining two former plots. These were tenement houses with rental apartments. They had separate communication, although the layout remained the same (e.g., houses at 2 and 3 Rynek Street, eastern façade). The differences between the earlier buildings and those of the 19th century can be traced through the examples of these houses. Both tenements were set gable-end to the market square, had four axes, were cellar-built, and had two floors. The façade decoration gave an impression of enlarged volume. They referred to classical architecture models with strong horizontal divisions in the form of cornices, numerous details in the form of window and door surrounds, and bossage. The storefronts in these houses were also larger (e.g., the house at 8 Rynek Street from 1899, at 7 Rynek Street from around 1900, and at 28 Wojska Polskiego Street, with the year 1900 marked at the gable).
At the beginning of the 20th century, various types of construction were used in Trzebiatów. Around 1907, right next to the city walls, near the former Gryfice Gate, an unknown townsman built a tenement house in the Art Nouveau style. The façades of the house were decorated with motifs of swans, delicate mallow branches, and other details typical of the style. Around 1911, one of the largest tenements within the city walls was erected on the corner of the present-day Witosa Street. The building had a mansard roof and was decorated with cartouches, but its form was closer to Baroque architecture than Art Nouveau.
In the 1930s, several houses at 9, 10, and 26 Rynek Street were remodeled. The old house at 9 Rynek Street was demolished in 1925, and a new one was built on two plots. Like the neighboring house at No. 10, the buildings maintained an ahistorical style with modest decoration reduced to narrow cornices. The façade of the house at 26 Rynek Street took on forms characteristic of the 1930s, with large semi-circular windows on the first floor. The façade of the building from 1639 was decorated with sgraffito, depicting the elephant Hansken with its keeper. The painting was likely created due to an event related to the animal's performance in Trzebiatów (the first in Pomerania). Examples of modernist architecture from the 1940s also appeared (e.g., the house at 2 Szkolna Street, built of ceramic bricks, with a simple cubic form and brick façade).
After 1945
In 1945, the western frontage of the market square (6 houses with outbuildings from No. 18 to 23) and part of the development on the northeastern side of the town parish church were destroyed. In the 1970s, the western frontage was rebuilt, with several nearly identical buildings erected in place of the former houses, set gable-end to the market square. This method, as well as the building volumes, referred to the original character of the houses, but the façade design was executed in a form that did not reference any known style. During the same period, several multi-family, multi-story residential buildings were erected in two quarters to the north of the church, introducing elements that were completely foreign to the historical city layout. In the 1990s, the house at 6 Rynek Street was rebuilt in a form that referred to its pre-1945 state.
In the post-war period, the city's buildings were used, renovated, and reconstructed in ways that showed little respect for their historical value. Several timber-framed outbuildings were lost, a number of old houses were demolished, and most were renovated without historical and architectural research. Despite the errors in spatial development, the old town of Trzebiatów still represents a unique and richest ensemble of historical burgher houses in Western Pomerania. In 1996, Trzebiatów was included in the Ministry of Culture and National Heritage's "Saving Historic Towns" program.
References
Bibliography
Architecture in Poland
Architectural history
History of urban planning | Architecture in Trzebiatów | [
"Engineering"
] | 3,781 | [
"Architectural history",
"Architecture"
] |
78,822,998 | https://en.wikipedia.org/wiki/GeForce%2050%20series | The GeForce 50 series is an upcoming series of consumer graphics processing units (GPUs) being developed by Nvidia as part of its GeForce line of graphics cards, succeeding the GeForce 40 series. Announced at CES 2025, it will debut with the release of the RTX 5080 and RTX 5090 on January 30, 2025. It is based on Nvidia's Blackwell architecture featuring Nvidia RTX's fourth-generation RT cores for hardware-accelerated real-time ray tracing, and fifth-generation deep-learning-focused Tensor Cores. The GPUs are manufactured by TSMC on an improved custom 4NP process node.
Background
In March 2024, Nvidia announced the Blackwell architecture for its datacenter products. Like Ampere, Blackwell is a shared architecture between both consumer and datacenter products rather than distinct architectures released simultaneously like Ada Lovelace for consumers and Hopper for datacenter.
At the Game Awards in December 2024, a cinematic trailer for The Witcher IV was shown which had been pre-rendered on an "unannounced Nvidia GeForce RTX GPU". This was assumed to be an upcoming GeForce 50 series GPU. Following the RTX 50 series announcement, Nvidia confirmed that the trailer was "pre-rendered in Unreal Engine 5 on a GeForce RTX 5090". Later in the same month, it was reported that Nvidia had begun stockpiling GeForce 50 series units in U.S. warehouses due to a looming 10% import tariff and 60% tariff on Chinese imports that Donald Trump promised in his re-election campaign.
Announcement
On January 6, 2025, the GeForce 50 series was officially announced for both desktop and mobile devices during Nvidia's CES keynote in Las Vegas. The pricing announcement was met with surprise as the RTX 5080 at $999 was the same price that the RTX 4080 Super released at a year earlier despite the anticipated price increases. Nvidia CEO Jensen Huang claimed that the RTX 5070 could reach "RTX 4090 performance at $549" despite a heavy reliance on DLSS 4 upscaling and multi-frame generation rather than raw performance.
Features
Blackwell architecture
The GeForce 50 series is powered by the Blackwell microarchitecture which continues Ada Lovelace's emphasis on high graphics frequencies and large L2 caches. The Blackwell architecture introduces Nvidia RTX's fourth-generation RT cores for hardware-accelerated real-time ray tracing and fifth-generation Tensor Cores for AI compute and performing floating-point calculations.
GDDR7
RTX 50 series GPUs are the first consumer GPUs to feature GDDR7 video memory for greater memory bandwidth over the same bus width compared to the GDDR6 and GDDR6X memory used in the GeForce 40 series. RTX 50 series desktop GPUs use GDDR7 modules from Samsung due to them being available for validation earlier than modules from SK Hynix and Micron.
12V2×6 connector
The GeForce 50 series uses the 16-pin 12V2×6 connector which is a revision of the 12VHPWR connector featured on the GeForce 40 series. There were problems with the 12VHPWR connector melting on some RTX 4090 GPUs due to the connector not being fully seated and connector design flaws that did not implement a high enough safety and error tolerance. The 12V2×6 connector revision, published by PCI-SIG in July 2023, addressed this by shortening the four sense pins so the connector will not push any power if it has not been fully seated. The 12VHPWR design would still draw up to 150W of power even if the sense pins were not making full contact. 12V2×6 is backwards compatible with existing 12VHPWR cables and adapters.
Nvidia has mandated to its AIB partners that the 16-pin 12V2×6 connector be used on all RTX 50 series designs. With the GeForce 40 series, the 12VHPWR connector was only mandated on higher power cards such as the RTX 4070 Ti, RTX 4080 and RTX 4090 while RTX 4060, RTX 4060 Ti and RTX 4070 AIB designs had the option of using 8-pin PCIe connectors. The 600W-capable 12VHPWR connector would not have been necessary on sub-200W cards.
DLSS 4
The fourth generation of Deep Learning Super Sampling (DLSS) was unveiled alongside the RTX 50 series. DLSS 4 upscaling uses a new vision transformer-based model for enhanced image quality with reduced ghosting and greater image stability in motion compared to the previous convolutional neural network (CNN) model. DLSS 4 also allows a greater number of frames to be generated and interpolated based on a single traditionally rendered frame. This form of frame generation called Multi-Frame Generation is exclusive to the RTX 50 series while the GeForce 40 series is limited to one interpolated frame per traditionally rendered frame. Nvidia claims that DLSS 4's frame generation model uses 30% less video memory with the example of Warhammer 40,000: Darktide using 400MB less memory at 4K resolution with frame generation enabled. Nvidia claims that 75 titles will integrate DLSS 4 Multi-Frame Generation at launch, including Alan Wake 2, Cyberpunk 2077, Indiana Jones and the Great Circle, and Star Wars Outlaws.
Media Engine and I/O
The RTX 50 series includes DisplayPort 2.1b UHBR20 (80Gbps) with higher display output data rates to support high resolution and high refresh rate displays. The GeForce 40 series received criticism for only including DisplayPort 1.4a (32Gbps) while the competing Radeon RX 7000 series included DisplayPort 2.1 UHBR13.5 (54Gbps). At CES 2025, VESA announced a collaboration with Nvidia on the new DP80LL ("low loss") UHBR20 active cable standard. DP80LL allows for 80Gbps DisplayPort 2.1 cables up to 3 meters long as passive DP80 cables are limited in length due to signal integrity concerns.
The RTX 50 series introduces the ninth-generation NVENC encoder and sixth-generation NVDEC video decoder. For the first time in a consumer GeForce GPU, support is adding for encoding and decoding video in the 4:2:2 color format for professional-grade higher color depth.
Products
Desktop
GeForce 50 series desktop GPUs are the second consumer GPUs to utilize a PCIe 5.0 interface and the first to feature GDDR7 video memory. They are fabricated by TSMC using a further refined custom 5 nm node (not 4nm) dubbed 4NP.
Mobile
Laptops featuring GeForce 50 series laptop GPUs were shown at CES 2025. Laptops with RTX 50 series GPUs were paired with Intel's Arrow Lake-HX and AMD's Strix Point and Fire Range CPUs. Nvidia claims that Blackwell architecture's new Max-Q features can increase battery life by up to 40% over GeForce 40 series laptops. For example, Advanced Power Gating saves power by turning off areas of the GPU that are unused and the paired GDDR7 memory can run in an "ultra" low-voltage state. Initial RTX 50 series laptops will become available in March 2025 starting at $1,299.
Reception
RTX 5090
The RTX 5090 has generally received a very lukewarm reception citing reliance on AI, the fact that the card didn't become more power efficient and was basically a beefier version of RTX 4090 with much higher power consumption. Many reviewers called the RTX 50 series marketing deceitful considering that DLSS 4's multiframe generation cannot make unplayable games playable, it doesn't and cannot improve latency. Some reviewers even jokingly called it RTX 4090 Ti.
References
External links
Graphics cards
Nvidia
Nvidia graphics processors
Computer hardware
Computer-related introductions in 2025 | GeForce 50 series | [
"Technology",
"Engineering"
] | 1,706 | [
"Computer engineering",
"Computer hardware",
"Computer systems",
"Computer science",
"Computers"
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78,823,097 | https://en.wikipedia.org/wiki/Qian%20%28mass%29 | Qian (), called tsin (cin4) in Cantonese, tiền or đồng in Vietnamese, or "Chinese ounce" or "mace" in English, is a traditional Chinese unit for weight measurement. It originated in China before being introduced to neighboring countries in East Asia.
Nowaday, the mass of 1 qian equals 5 grams in mainland China, 3.75 grams in Taiwan,
3.7799 grams in Hong Kong, Singapore and Malaysia,
and 3.78 grams in Vietnam.
Qian is mostly used in the traditional markets, and famous for measuring gold, silver and Chinese medicines.
China Mainland
On June 25, 1959, the State Council of the People's Republic of China issued the "Order on the Unified Measurement System", retaining the market measure system, with minor amendment.
where 1 qian equals 5 grams, and 10 qiags equals 1 liang. The traditional Chinese medicine measurement system remains unchanged.
Taiwan
In 1895, Taiwan was ceded to Japan from China. The Japanese implemented the metric system, but the Taiwanese still followed their own habits and continued to use the old weights and measures of the Qing Dynasty. 1 Taiwan qian is equal to 3.75 grams, or 1/10 Taiwan liang.
Hong Kong and Macau
Hong Kong and Macau mass units
Currently, Hong Kong law stipulates that one qian is equal to 1/10 liang, which is 3.779936375 grams.
Similarly, Singapore law stipulates that one qian equals 3.7799 g. Malaysia has the same regulations as it is a former British colony as well.
Hong Kong troy units
These are used for trading precious metals such as gold and silver.
Vietnam
In Vietnam, the unit of qian is called "đồng or tiền": 1 đồng is equal to 3.78 grams or 10 phân by traditional value.
For more information on the Chinese mass measurement system, please see article Jin (mass).
See also
Chinese units of measurement
Hong Kong units of measurement
Taiwanese units of measurement
Vietnamese units of measurement
Notes
References
External links
中國度量衡#衡
市制
錢 (質量單位)
Units of mass
Chinese units of measurement
Customary units of measurement | Qian (mass) | [
"Physics",
"Mathematics"
] | 450 | [
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78,823,132 | https://en.wikipedia.org/wiki/HR%203562 | HR 3562 (HD 76566) is a visual binary consisting of a bluish-white hued variable star and a Sun-like secondary star in the southern constellation of Vela. It has the variable-star designation IY Velorum (abbreviated to IY Vel). With an apparent magnitude of 6.26, the brighter primary is near the limit for naked eye visibility. The fainter companion has an apparent magnitude of 12.639 and can be observed with a telescope with an aperture of 76 mm or wider. It is located approximately distant according to Gaia EDR3 parallax measurements, and is receding away from the Solar System at a heliocentric radial velocity of 22.0 km/s.
HR 3562A
This is a hot, luminous B-type subgiant (spectral type B3IV) with a mass of 5.644 and a radius of 5.648 . It radiates 832 times the luminosity of the Sun from its photosphere at an effective temperature of , almost three times hotter than the Sun (5,772 K). It is thought to be very young at around 36-38 million years old.
In 1982, Burki et al. reported that the star showed pulsations with multiple periods, namely 1.97 days, 1.73 days, and 1.66 days, all with amplitudes of several mmag that produce a combined peak-to-peak amplitude of about 0.04 mag. As such, they categorized the star as a multiperiodic slowly pulsating B-type star (SPB). In 1986, however, Balona & Laing were only able to confirm one major period of 2.22 days. Due to the small projected rotational velocity, they classified it as a rotating ellipsoidal variable instead, which would have been indicative of a close binary with an orbital period of 4.44 days. Further observations were conducted by Balona, who, in 1994, changed his position and concluded that the star was indeed a SPB, having discovered that the 2.22 day period he previously found was actually the mean of three distinct periods at 1.9566 days, 2.1072 days, and 2.4563 days. It shows similarities to HR 2680, another SPB.
HR 3562B
HR 3562 was first discovered to be a double star by John Herschel in 1836. In 2001, it was confirmed that this was a physical binary system rather than an optical double i.e., a pair of unrelated stars closely aligned by chance. The pair are spaced apart, based on the separation of 35.0 arcseconds. This secondary is a post-T Tauri star, currently in the main sequence, with a Sun-like mass (0.98-1.01 ) and a slightly cooler temperature of , emitting 64% the Sun's luminosity. The star is aged about 50-110 million years.
Footnotes
References
B-type subgiants
Slowly pulsating B-type stars
Binary stars
Vela (constellation)
3562
CD−44 04951
076566
043807
J08551918-4502298 | HR 3562 | [
"Astronomy"
] | 668 | [
"Vela (constellation)",
"Constellations"
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78,826,015 | https://en.wikipedia.org/wiki/Meizu%20X8 | The Meizu X8 is a mid-range smartphone developed and manufactured by Meizu. It was released on September 19, 2018, alongside the Meizu 16X, Meizu V8, and V8 Pro.
Design
The back panel and screen are made of glass. The sides of the smartphone are made of aluminum.
At the bottom, there is a USB-C connector, a speaker, and a microphone stylized as a speaker. At the top, there is a 3.5mm audio jack. On the left side of the smartphone, there is a slot for two SIM cards. On the right side, there are volume control buttons and a power button. The fingerprint scanner is located on the back panel.
The Meizu X8 was available in 3 colors: Black, Blue, and White.
Technical specifications
Processor
The smartphone is powered by a Qualcomm Snapdragon 710 processor and an Adreno 616 graphics processor.
Battery
БThe battery has a capacity of 3210 mAh and supports 24W fast charging using mCharge 4 technology.
Camera
The smartphone features a dual rear camera system consisting of a 12MP, f/1.9 wide-angle lens and a 5MP depth sensor with Dual Pixel phase detection autofocus. It can record video in 1080p at 30fps. The front-facing camera has a 20MP wide-angle lens with an aperture of f/2.0 and can record video in 1080p at 30fps.
Display
The phone's display has an IPS LCD screen, sizing about 6.2 inches, a 2220 x 1080 resolution (Full HD+) with an aspect ratio of 18.5:9 with a pixel density of 398 ppi, and a notch for the proximity sensor, speaker, and front camera.
Storage
The smartphone was sold in configurations of 4/64, 6/64, and 6/128 GB.
Software
The smartphone was initially released with Flyme 7.1, which was based on Android 8.0 Oreo. It was later updated to Flyme 8.1, built on Android 9 Pie. There were plans to upgrade the smartphone to Android 10, but due to a significant number of bugs, the update was canceled.
References
Discontinued smartphones
Mobile phones introduced in 2018
Mobile phones with multiple rear cameras
Android (operating system) devices
Phablets
Meizu smartphones | Meizu X8 | [
"Technology"
] | 486 | [
"Crossover devices",
"Phablets"
] |
78,826,190 | https://en.wikipedia.org/wiki/Giving%20Machine | A Giving Machine is a specialized vending machine that allows people to donate various items to select nonprofit organizations. The vending machines are put up in public areas throughout the world during the Christmas and holiday season by The Church of Jesus Christ of Latter-day Saints (also known as the LDS or Mormon Church).
Overview
The Church of Jesus Christ of Latter-day Saints partners with both multinational, national, and local charities in various cities throughout the world. These charities select items that will help them fulfill their mission. People using the machines select an item, which is symbolized by a car with a picture, the name of the item, the name of the charity requesting the item, and the price. After purchasing the item, the card drops into a collection bin that allows people to see the items that have been donated. At certain machines, people can take photos with the card to share on social media, with the intention of spreading the word.
Examples of items are a $2.00 box of macaroni and cheese, an $8.00 hygiene kit, a $200 emergency utility bill payment, and various priced livestock. The money from raised from the machines goes to the charity requesting the various items. The charities are expected to use the money for the requested item although occasionally will use it for other similar items or initiatives. The LDS Church does not keep any money from the machines, and pays for their upkeep and space rental from other funds.
Machines are generally staffed by local Latter-day Saints or Church service missionaries.
History
The first Giving Machine was unveiled in 2017 in Salt Lake City, Utah at the Joseph Smith Memorial Building on Temple Square and the number of locations has slowly increased. The machines were not available in 2020 due to the COVID-19 pandemic.
References
The Church of Jesus Christ of Latter-day Saints
Vending machines | Giving Machine | [
"Engineering"
] | 375 | [
"Vending machines",
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75,734,450 | https://en.wikipedia.org/wiki/T%20Layout | The T-Layout is an architectural and design concept for web applications, specifically tailored to improve the user experience on mobile devices. It features a horizontally scrollable container divided into three distinct sections, each spanning the full width of the screen, and was developed to optimise space usage and streamline navigation.
Background
The T-Layout introduces horizontal scrolling as a complementary method to the conventional pop-up-based navigation system in mobile web applications. In this layout, the central section which is visible by default upon accessing the application, facilitates the main content of a URL address and is flanked by two "helper" sections. This approach minimises the need for extensive user movements, in order to reach navigation controls typically located at the top of the screen.
It is aimed at enhancing the user experience on mobile devices by providing an easier way to access essential content such as the main navigation, e-commerce related screens, or user account related information, ensuring that those elements are readily accessible while requiring minimal user effort.
The T-Layout was first implemented by E (e-streetwear.com) in their mobile web app layout, and it was inspired by the interfaces of well-tested native mobile apps like Instagram and Revolut.
A study titled "Mobile Navigation and User Preferences Survey" indicated a preference among mobile app users for one-handed usage, primarily navigating with their thumb. These insights led to the T-Layout Experiment, which compared the efficiency of using swipe gestures to access navigational elements against reaching traditional navigation controls.
Development history
It was first released as the mobile layout of E in early 2023. It was originally developed based on six principles: user-centric functionality, lightweight filesize, HTML and CSS implementation with minimal or no use of JavaScript required, suitable both for browser and server-rendering architectures, intuitive design, and improved SEO.
The development of the T-Layout was driven by the necessity for more ergonomic and user-friendly interfaces in mobile web applications. Its design, reminiscent of the letter 'T', emerged as a solution to several usability challenges mobile device users face, emphasising ease of access and efficient screen space utilisation.
In July 2023, E formalised the concept and its technical specifications, introducing it to the web design and development community.
In October 2023 the "Mobile Navigation and User Preferences Survey" was conducted, establishing that the vast majority of individuals prefer to use mobile applications by holding the phone in a one-handed grip, utilising only the thumb for gestures when possible.
The subsequent "T-Layout Experiment", designed to measure the time in seconds and the distance (user effort) in pixels, required to access navigational elements by traditionally tapping on fixed-positioned controls compared to swiping anywhere on the screen. The results proved that swipe gestures require less time and much less effort.
Styling and features
The main characteristic of the T-Layout is its horizontal scrolling feature, which can improve navigation efficiency while preserving the functionality of traditionally structured user interfaces.
Its Implementation can be achieved with a combination of HTML and styling with CSS as well as precompiled Scss and Sass, CSS-in-JS, and styled JSX. It can be either a purely HTML/CSS solution but JavaScript can be utilised as well to add more specific functionalities, while It can be implemented to both existing and new applications. Its application in server-side rendering architectures will ensure that all its underlying principles apply.
Although principally each section in the layout has a distinct role and facilitates specific types of content, the T-Layout as a concept is versatile, and it is adaptable allowing modifications in the layout or how it's implemented to cater to the specific needs of different applications.
See also
References
External links
The T Layout Experiment. E. Retrieved 2024-01-06.
Mobile UX Preferences Survey. E. Retrieved 2024-01-06.
Responsive web design
Web applications
Web development
Mobile web
Usability
Design
Information architecture
Design
Human–computer interaction
Web design
Communication design
Internet properties established in 2010 | T Layout | [
"Technology",
"Engineering"
] | 837 | [
"User interfaces",
"Mobile web",
"Wireless networking",
"Web development",
"Software engineering",
"Interfaces",
"Communication design",
"Human–machine interaction",
"Design",
"Web design",
"Human–computer interaction"
] |
75,734,508 | https://en.wikipedia.org/wiki/Cynotelopus | Cynotelopus is a monotypic genus of pill millipedes, found in south west Australia. It was first described in 1986 by C. A. W. Jeekel. It consists of a single species: Cynotelopus notabilis.
References
Sphaerotheriida
Taxa described in 1986
Monotypic myriapod genera
Millipede genera
Endangered species | Cynotelopus | [
"Biology"
] | 78 | [
"Biota by conservation status",
"Endangered species"
] |
75,735,875 | https://en.wikipedia.org/wiki/Transverse%20arch | In architecture, a transverse arch is an arch in a vaulted building that goes across the barrel vault. A series of transverse arches sitting on tops of the columns on the sides of the nave was typical in the churches of Romanesque architecture (common since Carolingian times). By analogy, the term is also used to describe the transverse ribs of a groined vault and for any crosswise arch in modern buildings. An arc that goes in transverse direction, but carries an exposed wall on top, dividing the vault into compartments, is called a diaphragm arch.
In the historical buildings, the transverse arches provide support for purlins and roof ridge beams. They also subdivide the nave into bays. The springings of the arch are typically pinned to supports using wooden or steel ties, but the bulk of lateral thrust is terminated in the abutments.
See also
Separating arch, an arch parallel to the sides of the nave
References
Sources
Arches and vaults | Transverse arch | [
"Engineering"
] | 195 | [
"Architecture stubs",
"Architecture"
] |
75,735,877 | https://en.wikipedia.org/wiki/Zosurabalpin | Zosurabalpin (RG6006, Abx-MCP, Ro7223280) is an experimental antibiotic developed in a collaboration between the pharmaceutical company Roche and scientists from Harvard University, for the treatment of carbapenem-resistant Acinetobacter baumannii (CRAB). It targets a lipopolysaccharide transporter. It works by recognizing a composite binding site made up of both the Lpt transporter and its LPS substrate. The chemical family to which it belongs was first disclosed in 2019, but the particular structure of RG6006 remained confidential until publication of the testing results in 2023.
See also
Clovibactin
Novobiocin
Teixobactin
References
Antibiotics
Peptides
Heterocyclic compounds with 3 rings
Sulfur heterocycles
Biphenyls
Pyridines | Zosurabalpin | [
"Chemistry",
"Biology"
] | 182 | [
"Biomolecules by chemical classification",
"Biotechnology products",
"Antibiotics",
"Molecular biology",
"Biocides",
"Peptides"
] |
75,735,923 | https://en.wikipedia.org/wiki/HD%2017943 | HD 17943, or HR 859, is a high proper-motion star in the constellation of Eridanus. It has a right ascension of and a declination of . Its apparent magnitude is equal to 6.325. Based on parallax measurements from the Gaia spacecraft, it is at a distance of . It belongs to spectral class A4V.
This star is incorrectly called by the Bayer designation "Sigma Eridani" in the 1991 edition of the Bright Star Catalogue. Bayer's Sigma Eridani is in fact non-existent.
References
Eridanus (constellation)
A-type main-sequence stars
0859
BD-10 0569
017943
013421 | HD 17943 | [
"Astronomy"
] | 146 | [
"Eridanus (constellation)",
"Constellations"
] |
75,736,340 | https://en.wikipedia.org/wiki/Onsite%20Identification%20and%20Verification%20System | The Onsite Identification and Verification System (OIVS) is a mobile technology device used by Bangladesh's elite security force, the Rapid Action Battalion (RAB), to instantly identify and verify information about suspects and criminals in the field.
Background
Prior to OIVS, when RAB arrested suspects, officers had to transport them to the nearest RAB office to manually look up their fingerprints, national IDs, and other information in databases to identify them. This delay allowed criminals using fake identities or disguise to avoid proper identification.
To modernize operations and solve these problems, RAB's Communication and MIS Wing developed OIVS in 2021 as a field-based biometric and database identity verification system.
Technology
OIVS consists of a portable, smartphone-like device that can be operated anywhere through an internet connection. By inputting a suspect's fingerprint, national ID number, or date of birth into the OIVS device, officers can instantly pull up identification information and criminal history from connected government databases.
The system currently connects to Bangladesh's National ID, passport, criminal records, and prison records databases. More databases such as driving licenses may be integrated in the future.
The software for the device was made in Bangladesh, and the hardware were imported from abroad.
Future Development
Planned OIVS upgrades include:
Expanding database connectivity to driving licenses, immigration, and police databases
Enabling photo-matching capabilities along with biometrics
Improving security features on the devices
Usage
OIVS aids RAB in:
Identifying arrested suspects and criminals in the field, even those using disguises or fake IDs
Accessing prior criminal records and arrests for questioning and investigations
Adding biometric and biographical data on new suspects into the system
Identifying bodies of deceased individuals
Reuniting mentally disabled people separated from families.
As of early 2024, over 15 RAB battalions across Bangladesh have received OIVS devices and officer training. Company commanders currently operate the devices with strict security protocols.
The device has been used in the 2024 national election.
Impact
By facilitating rapid in-field suspect identification, OIVS has increased the speed and effectiveness of RAB's operations. Within months of launch, OIVS has aided investigations into over 10 major criminal cases. The technology has been credited with identifying wanted murder suspects, members of terrorist organizations, as well as unknown deceased bodies and mentally disabled people to return them to families faster.
Other uses
United States
The Online Insurance Verification System (OIVS) is an electronic insurance verification device mandated by the state of Alabama to enforce automobile insurance requirements. Implemented in 2013 after a pilot testing phase, OIVS allows authorized government agencies and law enforcement entities to instantly check if a vehicle has valid insurance coverage through integration with insurance company databases.
OIVS was established under Alabama Legislative Act 2011-688 which tasked the Alabama Department of Revenue with developing an online verification system. Insurance companies licensed in Alabama are required to cooperate by providing real-time access to auto insurance data through web services. This allows OIVS users to submit queries with details like VIN number, policy number and date, which insurance companies must confirm or deny current coverage for.
References
Rapid Action Battalion
Mobile technology
2024 Bangladeshi general election | Onsite Identification and Verification System | [
"Technology"
] | 648 | [
"nan"
] |
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