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Cyborg From comicbooks are characters including Deathlok and Victor "Cyborg" Stone; and manga and anime characters including 8 Man (the inspiration for "RoboCop"), Kamen Rider, Rudol von Stroheim, and "Ghost in the Shell's" Motoko Kusanagi. Playable characters such as, Kano, Jax, Cyrax, Sektor, Smoke, and Cyber Sub-Zero from the "Mortal Kombat" franchise, as well as Genji, an advanced cyborg ninja, who appears in "Overwatch" and "Heroes of the Storm," are examples of cyborgs in video games. The "Deus Ex" video game series deals extensively with the near-future rise of cyborgs and their corporate ownership, as does the "Syndicate" series. William Gibson's "Neuromancer" features one of the first female cyborgs, a "Razorgirl" named Molly Millions, who has extensive cybernetic modifications and is one of the most prolific cyberpunk characters in the science fiction canon. The cyborg was also a central part of singer Janelle Monáe's 48-minute video corresponding with the release of her 2018 album "Dirty Computer." This "emotion picture" intertwined the relationship between human and technology, highlighting the power of the digital on a futuristic, dystopian society. Monáe has previously referred to herself as an android, depicting herself as a mechanical organism often conforming to idealistic standards, thus using the cyborg as a way to detach from these oppressive structures | https://en.wikipedia.org/wiki?curid=20756967 |
Cyborg Sending humans to space is a dangerous task in which the implementation of various cyborg technologies could be used in the future for risk mitigation. Stephen Hawking, a renowned physicist, stated "Life on Earth is at the ever-increasing risk of being wiped out by a disaster such as sudden global warming, nuclear war... I think the human race has no future if it doesn't go into space." The difficulties associated with space travel could mean it might be centuries before humans ever become a multi-planet species. There are many effect of spaceflight on the human body. One major issue of space exploration is the biological need for oxygen. If this necessity was taken out of the equation, space exploration would be revolutionized. A theory proposed by Manfred E. Clynes and Nathan S. Kline is aimed at tackling this problem. The two scientists theorized that the use of an inverse fuel cell that is "capable of reducing CO2 to its components with the removal of the carbon and re-circulation of the oxygen..." could make breathing unnecessary. Another prominent issue is radiation exposure. Yearly, the average human on earth is exposed to approximately 0.30 rem of radiation, while an astronaut aboard the International Space Station for 90 days is exposed to 9 rem. To tackle the issue, Clynes and Kline theorized a cyborg containing a sensor that would detect radiation levels and a Rose osmotic pump "which would automatically inject protective pharmaceuticals in appropriate doses | https://en.wikipedia.org/wiki?curid=20756967 |
Cyborg " Experiments injecting these protective pharmaceuticals into monkeys have shown positive results in increasing radiation resistance. Although the effects of spaceflight on our body is an important issue, the advancement of propulsion technology is just as important. With our current technology, it would take us about 260 days to get to Mars. A study backed by NASA proposes an interesting way to tackle this issue through deep sleep, or torpor. With this technique, it would "reduce astronauts' metabolic functions with existing medical procedures". So far experiments have only resulted in patients being in torpor state for one week. Advancements to allow for longer states of deep sleep would lower the cost of the trip to mars as a result of reduced astronaut resource consumption. Theorists such as Andy Clark suggest that interactions between humans and technology result in the creation of a cyborg system. In this model "cyborg" is defined as a part biological, part mechanical system which results in the augmentation of the biological component and the creation of a more complex whole. Clark argues that this broadened definition is necessary to an understanding of human cognition. He suggests that any tool which is used to offload part of a cognitive process may be considered the mechanical component of a cyborg system | https://en.wikipedia.org/wiki?curid=20756967 |
Cyborg Examples of this human and technology cyborg system can be very low tech and simplistic, such as using a calculator to perform basic mathematical operations or pen and paper to make notes, or as high tech as using a personal computer or phone. According to Clark, these interactions between a person and a form of technology integrate that technology into the cognitive process in a way which is analogous to the way that a technology which would fit the traditional concept a cyborg augmentation becomes integrated with its biological host. Because all humans in some way use technology to augment their cognitive processes, Clark comes to the conclusion that we are "natural-born cyborgs". In 2010, the Foundation became the world's first international organization dedicated to help humans become cyborgs. The foundation was created by cyborg Neil Harbisson and Moon Ribas as a response to the growing number of letters and emails received from people around the world interested in becoming a cyborg. The foundation's main aims are to extend human senses and abilities by creating and applying cybernetic extensions to the body, to promote the use of cybernetics in cultural events and to defend cyborg rights. In 2010, the foundation, based in Mataró (Barcelona), was the overall winner of the Cre@tic Awards, organized by Tecnocampus Mataró. In 2012, Spanish film director Rafel Duran Torrent, created a short film about the Foundation | https://en.wikipedia.org/wiki?curid=20756967 |
Cyborg In 2013, the film won the Grand Jury Prize at the Sundance Film Festival's Focus Forward Filmmakers Competition and was awarded with US$100,000. Given the technical scope of current and future implantable sensory/telemetric devices, these devices will be greatly proliferated, and will have connections to commercial, medical, and governmental networks. For example, in the medical sector, patients will be able to login to their home computer, and thus visit virtual doctor's offices, medical databases, and receive medical prognoses from the comfort of their own home from the data collected through their implanted telemetric devices. However, this online network presents huge security concerns because it has been proven by several U.S. universities that hackers could get onto these networks and shut down peoples’ electronic prosthetics. These sorts of technologies are already present in the U.S. workforce as a firm in River Falls, Wisconsin called Three Square Market partnered with a Swedish firm called Biohacks Technology to implant RFID microchips in the hands of its employees (which are about the size of a grain of rice) that allow employees to access offices, computers, and even vending machines. More than 50 of the firms 85 employees were chipped. It was confirmed that the U.S. Food and Drug Administration approved of these implantations | https://en.wikipedia.org/wiki?curid=20756967 |
Cyborg If these devices are to be proliferated within society, then the question that begs to be answered is what regulatory agency will oversee the operations, monitoring, and security of these devices? According to this case study of Three Square Market, it seems that the FDA is assuming the role in regulating and monitoring these devices. | https://en.wikipedia.org/wiki?curid=20756967 |
Sofinnova is the name shared by two venture capital firms, Ventures and Partners. The name is believed to be a contraction of the French, "Société de Financement de l’Innovation" or, Innovation Venture Capital Company. Both firms trace their roots back to SA, an investment institution founded in Paris in 1972. The two firms have raised ~$4B since inception, and shared a similar investment strategy of investing in the life science and technology sectors. The two sister firms distinguish themselves on the basis of their target geographies, and have been fully independent since 1997. Ventures and Partners have had historically some of the same Limited Partners, and have co-invested together in several life science companies including: Flamel, Cerep, Genset, Actelion, Preglem, Movetis, Ascendis, Obseva, Auris and Nucana. Both firms work together in a collegial way to exchange information and due diligence in each other's respective geographies. The firms do not have an obligation to show each other deals or to co-invest, but historically have co-invested together in ~10% of their collective investments. Ventures is an independent venture capital firm based in Menlo Park. Ventures has been an active venture investor, investing in some well-known venture investments of the period. Ventures has backed companies including: Millennium Pharmaceuticals, Kosan Biosciences, Actelion, Intermune, Seattle Genetics, Cotherix, Threshold Pharmaceuticals, Prestwick, Preglem, Movetis, Intellikine, Amarin Corporation, Salveo, and Labrys | https://en.wikipedia.org/wiki?curid=20765003 |
Sofinnova The San Francisco office of Ventures was often remembered for having an original 18 ft. mosasaurus in the office of one of the Managing Partners (Mike Powell). Ventures closed their San Francisco office in 2011, and combined their Bay Area offices into a single office on Sand Hill Road in Menlo Park. Ventures has raised several venture capital funds (see Table). The earlier funds, SVP I through V, were predominantly information technology (IT), wherein the later funds were predominantly life science focused. SVP VIII and IX were exclusively life science only, with emphasis on Phase 2 and 3 drug development. SVP IV was Ventures' initial fund after the reorganization of in 1997. Each of the funds from SVP V through SVP IX exceeded the target raise, and closed at the maximum amount as allowed by the Limited Partner agreements. Partners is an independent venture capital firm based in Paris with approximately €1.7 billion of capital. The firm invests in early stage companies and corporate spin-offs, in clean technology and life science: has financed more than 460 companies in Europe since inception 1972 of which more than 20% have successfully completed an initial public offering and more than 20% have been acquired by strategic buyers. Following the separation of the two firms, Partners completed fundraising for its third private equity fund, Capital III with €121M. Among the investments in this fund are Innate, Maximiles and NovusPharma | https://en.wikipedia.org/wiki?curid=20765003 |
Sofinnova Sofinnova's fourth fund which raised €330M of capital made one of the largest venture firms in Europe at the time. In 2005, Partners was named “Fund of the Year” by Private Equity International and “VC Techno House of the Year 2005” by the European Venture Capital Journal (EVCJ) which described Sofinnova's fundraising as the, “Fundraising of the Year 2005”. This fund invested in a number of companies including Taptu. Partners has raised several venture capital funds (see Table). | https://en.wikipedia.org/wiki?curid=20765003 |
Halvor Heyerdahl Rasch (8 January 1805 – 26 August 1883) was a Norwegian zoologist and educator. He was born at Eidsberg in Østfold, Norway. Rasch studied botany and zoology at the University of Christiania (now University of Oslo). An avid hunter and sportsman, he published the book "Jagten i Norge" (1845) as well as works about livestock, oyster cultivation and beekeeping. He was among the founders of the "Centralforeningen for Udbredelse af Legemsøvelser og Vaabenbrug", a precursor to the Norwegian Confederation of Sports, in 1861. Rasch was decorated as a Knight of the Royal Norwegian Order of St. Olav in 1863 and received the Silver Medal of the Société Impériale Zoologique d'Acclimatation at Paris in 1866. | https://en.wikipedia.org/wiki?curid=20769891 |
NGC 35 is a spiral galaxy in the Cetus constellation. | https://en.wikipedia.org/wiki?curid=20776375 |
Progradation In sedimentary geology and geomorphology, the term progradation refers to the growth of a river delta farther out into the sea over time. This occurs when the mass balance of sediment into the delta is such that the volume of incoming sediment is greater than the volume of the delta that is lost through subsidence, sea-level rise, and/or erosion. can be caused by: | https://en.wikipedia.org/wiki?curid=20776529 |
Rotational Brownian motion is the random change in the orientation of a polar molecule due to collisions with other molecules. It is an important element of theories of dielectric materials. The polarization of a dielectric material is a competition between torques due to the imposed electric field, which tend to align the molecules, and collisions, which tend to destroy the alignment. The theory of rotational Brownian motion allows one to calculate the net result of these two competing effects, and to predict how the permittivity of a dielectric material depends on the strength and frequency of the imposed electric field. was first discussed by Peter Debye, who applied Albert Einstein's theory of translational Brownian motion to the rotation of molecules having permanent electric dipoles. Debye ignored inertial effects and assumed that the molecules were spherical, with an intrinsic, fixed dipole moment. He derived expressions for the dielectric relaxation time and for the permittivity. These formulae have been successfully applied to many materials. However, Debye's expression for the permittivity predicts that the absorption tends toward a constant value when the frequency of the applied electric field becomes very large—the "Debye plateau". This is not observed; instead, the absorption tends toward a maximum and then declines with increasing frequency | https://en.wikipedia.org/wiki?curid=20793410 |
Rotational Brownian motion The breakdown in Debye's theory in these regimes can be corrected by including inertial effects; allowing the molecules to be non-spherical; including dipole-dipole interactions between molecules; etc. These are computationally very difficult problems and rotational Brownian motion is a topic of much current research interest. | https://en.wikipedia.org/wiki?curid=20793410 |
Sabine Flitsch is a German organic chemist and chemical biologist who holds a personal chair in Chemical Biology at the University of Manchester School of Chemistry, where she runs an active research glycobiology research group based in the Manchester Interdisciplinary Biocentre . Flitsch was born in Münster, North Rhine-Westphalia and was educated at the University of Münster, where she received a First class Degree and Diploma in Chemistry. She subsequently received a Michael Wills scholarship scholarship to study for a D.Phil at the University of Oxford, where she worked under the supervision of Sir Jack Edward Baldwin, FRS. She is the daughter of the noted organic chemist Professor Wilhelm Flitsch. Her sister, Mareile Flitsch, is a sinologist, Professor and Director of the Ethnographic Museum of the University of Zurich. All three Flitcsh family members are alumni of the University of Münster, the institution from which she received her Diploma in 1982. Following her PhD, Flitsch took up a DAAD Postdoctoral Fellowship at the Massachusetts Institute of Technology, where she worked with Professor Har Gobind Khorana. In 1988, she returned to the University of Oxford and took up a lectureship in Organic Chemistry, which she held for the next 6 years. She joined the University of Edinburgh in 1995, and was an independent BBSRC Career Research Development Fellow between 2001 and 2004. In October 2004, Flitsch was awarded a personal Chair in Chemical Biology at the University of Manchester in the Department of Chemistry | https://en.wikipedia.org/wiki?curid=61923265 |
Sabine Flitsch Based at The Manchester Institute of Biotechnology, she is currently one of three professors of chemical biology. Additionally, Professor Flitsch is an elected member of the Royal Society of Chemistry Council of the United Kingdom and a director of the spin-out company Bio-Shape ltd. Flitsch is also currently the Scientific Director of IBCarb and CarboMet networks and is a director of the biotechnology spin-out company Bio-Shape Ltd. Flitsch’s research is focussed on glycobiotechnology – the study of carbohydrates in applied science and biocatalysis – the application of enzymes in sustainable chemical manufacture. She is particularly recognised for her work at the interface of these two fields (glycoenzymology). Her research career spans over 35 years and has included many examples of pioneering work. Current research interests include the chemical analysis and biological exploitation of carbohydrates, and the creation of tools and resource ‘toolboxes’ for furthering research and innovation in basic and applied glycoscience. During her postdoctoral research at MIT, Flitsch was involved in mutagenic studies of bacterial membrane proteins to help study protein folding in micelle membrane-like models. She was also instrumental in the development of cysteine mutant technology for biorthogonal labelling of proteins. She has also expanded this work to encompass modifications for spin labelling, and the study of glycoproteins and their analysis on gold plates and nanoparticles | https://en.wikipedia.org/wiki?curid=61923265 |
Sabine Flitsch These approaches were complemented by the use of enzymatic modifications of polysaccharides and glycoproteins to facilitate analysis, for which Prof. Flitsch’s research group has engineered tailored biocatalysts via directed evolution, and to address the biological challenge of 'sequencing' carbohydrates through chemical and conformational means. Detailed studies of enzyme reactions have also provided new insights into the effect of interfaces on enzyme catalysis and allowed new methods for surface chemistry and synthesis of biomolecules Flitsch's use of recombinant enzymes extends into the field of sustainable chemical manufacture, encompassing the discovery, development and demonstration of a range of biocatalysts for production of fine chemical and pharmaceutical building blocks. Recently Prof. Flitsch has been at the forefront of biocatalytic research, constructing enzyme cascades and artificial synthetic pathways to allow multistep syntheses under common reaction conditions. and new approaches to high-resolution glycan analysis using ion mobility mass spectrometry </ref> Through her interdisciplinary research group, Sabine has supported the research training of over 100 staff and students. Her mentorship and guidance has allowed many of these to advance into principal investigators at a variety of institutions worldwide. Sabine has been an active in the promotion of science and research to policy makers and the wider community | https://en.wikipedia.org/wiki?curid=61923265 |
Sabine Flitsch As part of a successful bid to present at the Summer Science Exhibition 2013 hosted by the Royal Society in London, Flitsch’s research was showcased along with collaborators from across the UK, through a series of hands-on activities and demonstrations. The initiative, called “The Complex Life of Sugars”, has become a permanent feature of the Programme of Public Engagement with Research and Researchers at the Manchester Institute of Biotechnology. As part of this it has been showcased at numerous national outreach events (Great British Bioscience Festival 2014, Royal Society Satellite Exhibition 2016, New Scientist Live! 2016) as well as locally as part of initiatives to reach non-traditional outreach audiences (ScienceX at the Trafford Centre). She has also represented the local authority as a governor of a secondary school within Greater Manchester. As director of the IBCarb Network in Industrial Biotechnology and Bioenergy, Flitsch was able to drive forward the strategy for academic and industrial collaboration in the UK, following on from a whitepaper “Roadmap for Glycoscience in Europe”, which she co-authored. The work of this network has been replicated by an EU Coordination and Support Action (CarboMet) also directed by Prof. Fltisch. Additionally, she was part of a Scientist-MEP pairing scheme to aid links between research and scientific policy. She has also acted as an external examiner at a number of UK universities, including St. Andrews, Imperial College London, Liverpool, Hull and Leicester | https://en.wikipedia.org/wiki?curid=61923265 |
Sabine Flitsch Flitsch has been nominated for and awarded many prizes including the Zeneca Research Award (1996), the Glaxo Wellcome Award for Innovative Chemistry (1997) and is the recipient of a Royal Society Wolfson Merit Award (2007-2012) and a Royal Society of Chemistry Interdisciplinary Award (2014) | https://en.wikipedia.org/wiki?curid=61923265 |
UV detectors An Ultraviolet dectector (also known as UV detector or UV-Vis detector) is a type of non-destructive chromatography detector which measures the amount of ultraviolet or visible light absorbed by components of the mixture being eluted off the chromatography column. They are often used as detectors for high-performance liquid chromatography. | https://en.wikipedia.org/wiki?curid=61925301 |
Koenigsberger ratio The is the proportion of remanent magnetization relative to induced magnetization in natural rocks. It was first described by . It is a dimensionless parameter often used in geophysical exploration to describe the magnetic characteristics of a geological body for help in interpreting magnetic anomaly patterns. The total magnetization of a rock is the sum of its natural remanent magnetization and the magnetization induced by the ambient geomagnetic field. Thus, a Koenigsberger ratio, "Q", greater than 1 indicates that the remanence properties contribute the majority of the total magnetization of the rock. | https://en.wikipedia.org/wiki?curid=61933545 |
Probe electrospray ionization (PESI) is an electrospray-based ambient ionization technique which is coupled with mass spectrometry for sample analysis. Unlike traditional mass spectrometry ion sources which must be maintained in a vacuum, ambient ionization techniques permit sample ionization under ambient conditions, allowing for the high-throughput analysis of samples in their native state, often with minimal or no sample pre-treatment. The PESI ion source simply consists of a needle to which a high voltage is applied following sample pick-up, initiating electrospray directly from the solid needle. is an ambient ionization mass spectrometry technique developed by Professor Kenzo Hiraoka et al. at the University of Yamanashi, Japan. The technique was developed to address some of the issues associated with traditional electrospray ionization (ESI), including clogging of the capillary and contamination, whilst providing a means of rapid and direct sample analysis. Since its initial conception, various modified forms of the PESI ion source have been developed, and the PESI-MS system has been commercialized by instrument manufacturing company Shimadzu. The PESI ion source consists of a solid needle or wire which acts as both the sampling probe and electrospray emitter. The needle is moved up and down along a vertical axis, a process which can be either automated or manual. When the needle is lowered to the sampling stage, the tip of the needle briefly touches the surface of a typical liquid sample | https://en.wikipedia.org/wiki?curid=61952795 |
Probe electrospray ionization During this stage, the needle is held at ground potential. The needle is then raised to be level with the mass spectrometer inlet where a high voltage of 2-3 kV is applied. Electrospray is induced at the tip of the needle, producing analyte ions which are drawn into the mass spectrometer for analysis. The mechanism by which ions are formed is believed to be identical to traditional electrospray ionization. As a result, in positive ion mode analytes are often observed as the protonated, sodiated and potentiated ions, depending on the sample and analyte type. Although the amount of sample picked up by the needle is largely dependent on sample viscosity, it has been estimated that just a few picolitres of the sample solution are typically used. Because of this, the technique can be applied to small sample sizes, particularly ideal when limited sample amounts are available. As such a small sample amount is picked up and completely exhausted during the ionization process, issues of contamination are severely reduced. Furthermore, the process of sampling and ionization takes just a few seconds, so PESI-MS is suitable for high-throughput analysis. An interesting phenomenon observed with probe electrospray ionization is the sequential and exhaustive ionization of analytes with different surface activities. During the development of PESI, it was discovered that analytes could be sequentially ionized throughout the electrospray, thus enabling a temporal separation of components within a sample | https://en.wikipedia.org/wiki?curid=61952795 |
Probe electrospray ionization In normal ESI, the sample solution is typically continuously supplied through a capillary and the charged droplets contain all sample components, with more surface-active analytes being constantly preferentially ionized. In PESI, surface-active analytes are also preferentially ionized. However, as a finite droplet exists on the tip of the needle, following the depletion of surface-active analytes, the remaining components in the droplet can then be ionized and observed. This can result in the production of distinctively different mass spectra from a single sample over the application of the high voltage for just a few seconds. This effect offers a particular advantage in the analysis of analytes suffering from ion suppression effects. The presence of surface-active analytes or charged solvent additives can result in the suppressed ionization of analytes of interest, resulting in low sensitivity or the complete absence of the analyte. The effects of ion suppression can be minimized by reducing the complexity of the sample, for instance through sample extraction techniques such as solid phase extraction, or by separation of analytes of interest using chromatographic separation. However, these sample preparation steps can be laborious, time-consuming and expensive. PESI enables a reduction in ion suppression without the need for sample pre-treatment. By separating the ionization of different analytes, components causing ion suppression can be exhausted before enabling the ionization of components of interest | https://en.wikipedia.org/wiki?curid=61952795 |
Probe electrospray ionization This has been demonstrated in a number of scenarios, including in the analysis of raw urine, with concentrated components such as creatinine ionization initially, followed by the appearance of previously undetected metabolites. As the PESI needle is only applicable to liquid or penetrable solid samples, it cannot be used for the analysis of the majority of dry solid materials. To circumvent this limitation, sheath-flow probe electrospray ionization (sfPESI) was developed, a modification of the traditional PESI technique. The sfPESI ion source consists of a solid needle housed within a plastic sheath (typically a gel-loading tip) filled with a small amount of solvent. The needle protrudes from the base of the sheath by approximately 0.1 mm, where a minute solvent droplet is held. The based of based the probe is briefly touched to the sample surface, where a convex solvent meniscus forms between the probe and the sample, wetting the sample and enabling analyte extraction. The chemistry of the solvent can be modified to induce the extraction of particular analytes of interest. After application to the sample, the sfPESI probe is then raised to be level with the mass spectrometer inlet, with solubilised analytes held in the droplet at the tip of the needle, and a high voltage applied. sfPESI offers the same advantages as standard PESI, including the sequential and exhaustive ionization phenomenon, whilst enabling the direct analysis of dry samples | https://en.wikipedia.org/wiki?curid=61952795 |
Probe electrospray ionization PESI-MS has proven to be particularly effective in the metabolic analysis of biological materials, having been applied to the analysis of cancerous and non-cancerous breast tissue, as well as brain and liver tissue removed from mice. Interestingly, PESI-MS has recently been applied to the direct analysis of living animals for real-time metabolic profiling. Due to the narrow diameter of the PESI needle and brief sample introduction time, PESI is reasonably non-invasive. As a result, the technique has been used to sample from the organs of living anaesthetized animals, specifically to analyse metabolites in the brain, spleen, liver and kidney of a living mouse. In addition to this, PESI-MS has been applied to the on-site analysis of food products for the purpose of quality control, to the detection of herbicides in body fluids to demonstrate exposure, and finally to the detection of illicit drugs in bodily fluids to indicate drug use. Several groups have also harnessed the small size of the PESI probe to achieve single-cell analysis, demonstrating the capability of rapidly detecting metabolites at cellular and subcellular levels. The PESI modification known as sheath-flow PESI has been applied to the analysis of various solid samples in their native state, including pharmaceutical tablets, illicit drugs, food and agricultural products, and pesticides. In addition, sfPESI has been utilised in the field of forensic science for the analysis and identification of fresh and dried body fluids of forensic interest | https://en.wikipedia.org/wiki?curid=61952795 |
Probe electrospray ionization In this work, sfPESI was also coupled with tandem mass spectrometry (MS/MS), demonstrating the capability of ion fragmentation for identification of unknown components. | https://en.wikipedia.org/wiki?curid=61952795 |
ACS Omega is a peer-reviewed scientific journal published since 2016 by the American Chemical Society. Its publication frequency is weekly and the current editor-in-chiefs are Krishna Ganesh and Deqing Zhang. The journal has published 4,250 peer-reviewed articles between July 2016–May 2019 and has a median time from submission to first decision at 22 days. | https://en.wikipedia.org/wiki?curid=61965092 |
C12H16O6 The molecular formula CHO (molar mass: 256.252 g/mol) may refer to: | https://en.wikipedia.org/wiki?curid=61975691 |
Gražvydas Lukinavičius (born 29 November 1978) is a Lithuanian biochemist. His scientific interest and main area of research is focused on labeling of biomolecules and visualization using super-resolution microscopy. He is co-invertor of DNA labeling technology known as Methyltransferase-Directed Transfer of Activated Groups (mTAG) and biocompatible and cell permeable fluorophore – silicon-rhodamine (SiR). Both inventions were commercialized. He is studying labeling methods and apply them for chromatin dynamics visualization in living cells. He was born in the family of an electrician and a land development specialist. Lukinavičius finished secondary school in Jurbarkas. Lukinavičius completed his bachelor's degree and master's degree in biochemistry at the Vilnius University in 2000 and 2002 respectively. During this period he worked as a research assistant in Saulius Klimašauskas group and investigating conformational movements of the catalytic loop of DNA methyltransferase. Later he became interested in S-Adenosyl methionine analogues which can be cofactors for methyltransferases. He collaborated with Elmar Weinhold from RWTH Aachen University and learned chemical synthesis and received his PhD in biochemistry at Vilnius University, Lithuania in September 2007. This led to the development of a new DNA labeling method, the Methyltransferase-Directed Transfer of Activated Groups (mTAG). This method was applied for optical DNA mapping and for a profiling epigenetic modifications by several research groups | https://en.wikipedia.org/wiki?curid=61984823 |
Gražvydas Lukinavičius After obtaining his PhD, he moved to École polytechnique fédérale de Lausanne for postdoctoral research where he continued on working with protein labeling methods in group of Kai Johnsson. He improved SNAP-tag protein labelling technology by developing a new biocompatible fluorophore, silicon-rhodamine (SiR). During this period, he began a collaboration with Stefan Hell to perform one of the first super-resolution microscopy experiments of living cells. In 2016, Stefan Hell invited Lukinavičius to the Department of NanoBiophotonics of the Max Planck Institute for Biophysical Chemistry in Göttingen. He has continued working on fluorescence labeling of biomolecules and started a Chromatin Labeling and Imaging group in 2018. His most-cited publications, according to "Google Scholar" are: | https://en.wikipedia.org/wiki?curid=61984823 |
Water distribution system A water distribution system is a part of water supply network with components that carry potable water from a centralized treatment plant or wells to water consumers in order to adequately deliver water to satisfy residential, commercial, industrial and fire fighting requirements. A definition uses the term water distribution network for a portion of a water distribution system up to the service points of bulk water consumers or demand nodes that many consumers are lumped up together. World Health Organization (WHO) uses the term water transmission system for a network of pipes, generally in tree-like structure that is used to convey water from water treatment plants to service reservoirs, and uses the term water distribution system for a network of pipes that generally has a loop structure to supply water from the service reservoirs and balancing reservoirs to water consumers. A water distribution system consists of pipelines, storage facilities, pumps, and other accessories. Pipelines laid within public right of way called water mains are used to transport water within a distribution system. Large diameter water mains called primary feeders are used to connect between water treatment plants and service areas. Secondary feeders are connected between primary feeders and distributors. Distributors are water mains that are located near the water users, which also supply water to individual fire hydrants | https://en.wikipedia.org/wiki?curid=61988019 |
Water distribution system A service line is a small diameter pipe used to connect from a water main through a small tap to a water meter at user's location. There is a service valve (also known as curb stop) on the service line located near street curb to shut off water to the user's building. Storage facilities, or distribution reservoirs, provide clean drinking water storage to ensure the system has enough water to service in fluctuating demands (service reservoirs), or to equalize the operating pressure (balancing reservoirs). They can also be temporarily used to serve fire fighting demands during a power outage. There can be many types of distribution reservoirs. A surface reservoir is a larger storage facility built on the ground with the wall lined with concrete, shotcrete, asphalt, or membrane. When a surface reservoir at the ground level cannot provide a sufficient hydraulic head to the distribution system, an elevated water tower can also be used. A standpipe is slightly different from an elevated water tower in that the standpipe allows water storage from the ground level to the top of the tank. The bottom storage area is called supporting storage, and the upper part which would be at the similar height of an elevated water tower is called useful storage. Storage facilities are typically located at the center of the service locations. Being at the central location reduces the length of the water mains to the services locations. This reduces the friction loss when water is transported over a water main | https://en.wikipedia.org/wiki?curid=61988019 |
Water distribution system In general, a layout of a water distribution system can be classified as grid, ring, radial or dead end system. A grid system follows the general layout of the grid road infrastructure with water mains and branches connected in rectangles. With this topology, the water can be supplied from many directions allowing good water circulation and redundancy if a section of the network is broken down. Drawbacks of this topology include difficulties of sizing the system. A ring system is a topology with each water main that go to each road, and there is a sub-main that is branched off the water main to provide a circulation of two directions. This system has some advantages of the grid system, but it is easier to make a determination of sizing. A radial system delivers water into multiple zones. At the center of each zone, the water is delivered radially toward the customers. A dead end system has water mains along the roads without a particular pattern for towns that do not have road network patterns. As there are no connectivities between the mains, water can have less circulation and can have stagnation. The integrity of the systems are broken down into physical, hydraulic, and water quality. The physical integrity includes concerns on the ability of the barriers to prevents contaminations from the external sources to get into water distribution systems. The deterioration can be caused by physical or chemical factors | https://en.wikipedia.org/wiki?curid=61988019 |
Water distribution system The hydraulic integrity is an ability to maintain adequate water pressure inside the pipes throughout distribution systems. It also includes the circulation and length of time that the water travels within a distribution system which has impacts on the effectiveness of the disinfectants. The water quality integrity is a control of degradations as the water travels through distribution systems. The impacts of water quality can be caused by physical or hydraulic integrity factors. The water quality degradations can also take place within the distribution systems such as microorganism growth, nitrification, and internal corrosion of the pipes. Analyses are done to assist in design, operation, maintenance and optimization of water distribution systems. There are two main types of analyses: hydraulic, and water quality behavior as it flows through a water distribution system. Hazards in water distribution systems can be in the forms of microbial, chemical and physical. Most microorganisms are harmless within water distribution systems. However, when infectious microorganisms enter the systems, they form biofilms and create microbial hazards to the users. Biofilms are usually formed near the end of the distribution where the water circulation is low. This supports their growth and makes disinfection agents less effective | https://en.wikipedia.org/wiki?curid=61988019 |
Water distribution system Common microbial hazards in distribution systems come from contamination of human faecal pathogens and parasites which enter the systems through cross-connections, breaks, and water main works, and open storage tanks. Chemical hazards are those of disinfection by-products, leaching of piping materials and fittings, and water treatment chemicals. Physical hazards include turbidity of water, odors, colors, scales which are buildups of materials inside the pipes from corrosions, and sediment resuspension. There are several bodies around the world that create standards to limit hazards in the distribution systems: NSF International in North America; European Committee for Standardization, British Standards Institution and Umweltbundesamt in Europe; Japanese Standards Association in Asia; Standards Australia in Australia; and Brazilian National Standards Organization in Brazil. Lead contamination in drinking water can be from leaching of lead that was used in old water mains, service lines, pipe joints, plumbing fittings and fixtures. According to WHO, the most significant contributor of lead in water in many countries is the lead service line. Water quality can be deteriorated by the internal corrosion of piping in distribution systems. This includes the corrosion of metal pipe surfaces and connections. The problems create health concerns, colors, taste and odor in water. Health concerns are related to releases trace metal such as lead, copper or cadmium to the water | https://en.wikipedia.org/wiki?curid=61988019 |
Water distribution system Lead exposure can cause delays in physical and mental development in children. Long term exposure to copper may cause liver and kidney damage. High or long term exposure of cadmium may cause damage to various organs. Corrosion of iron materials causes the discoloring of the water that is shown as rust-coloured water or red water. Corrosion of zinc and iron can cause metallic taste. Various techniques can be used to control internal corrosions, for example, pH level adjustment, adjustment of carbonate and calcium to create calcium carbonate as piping surface coating, and applying a corrosion inhibitor. An example of corrosion inhibitor is using phosphate products to form films over pipes. This reduces the chance of leaching of trace metal from the pipe materials into the water. Hydrant flushing is scheduled releases of water from fire hydrants or special flushing hydrants to release iron and other mineral deposits from the water main. Another benefit of using fire hydrants for water main flushing is to ensure that the water is adequately supplied to fire hydrants for fire fighting. During the hydrant flushing, consumers may notice rust color in their water as the iron and mineral deposits are stirred up in the process. After water mains are put in service for a long time, there will be deteriorations in structural, water quality, and hydraulic performances. Structural deterioration may be caused by many reasons. Metal-based pipes develop internal and external corrosion, causing the pipe walls to thin or degrade | https://en.wikipedia.org/wiki?curid=61988019 |
Water distribution system They can eventually leak or bust. Cement-based pipes are subjected to cement matrix and reinforced steel deterioration. All pipes are subjected to joint failures. Water quality deterioration includes scaling or tuberculation, sedimentation, and biofilm formation. Scaling is a formation of hard deposits on the interior wall of the pipes. This can be a by-product of the pipe corrosion that is combined with calcium in the water, which is called tuberculation. Sedimentation is when solids are settled within the pipes, usually at recesses between the scaling build-ups. When there is a change in the velocity of water flow (such as sudden use of a fire hydrant), the settled solids will be stirred up causing water to be discolored. Biofilms can be developed in highly scaled pipes where bacteria is allowed to grow as the higher the roughness of the interior wall, the harder it is for disinfectant to be effective by reaching the surface of the pipe wall. Hydraulic deterioration which affect pressures and flows can be a result of other deteriorations that obstruct the water flow. When it is time for a water main renewal, there are many considerations involved in choosing the method of renewal. This can be open-trench replacement, or one of the pipeline rehabilitation methods. A few pipeline rehabilitation methods are pipe bursting, sliplining, and pipe lining. When an in-situ rehabilitation method is used, a benefit is the lower cost as there is no need to have excavation along the water main pipeline | https://en.wikipedia.org/wiki?curid=61988019 |
Water distribution system Only small pits are excavated to access the existing water main. The unavailability of the water main during the rehabilitation, however, requires building a temporary water bypass system to serve as the water main in the affected area. A temporary water bypass system (known as temporary bypass piping) should be carefully designed to ensure the adequate water supply to the customers in the project area. Water is taken from a feed hydrant into a temporary pipe. When the pipe crosses a driveway or a road, a cover or a cold patch should be put in place in order to allow cars to cross the temporary pipe. Temporary service connections can be made to the temporary pipe to connect to homes. There are many ways to perform a connection, one of which is to connect the temporary service connection to a garden hose. The temporary pipe should also add temporary fire hydrants for fire protection. As water main work can disturb lead service lines which can result in elevated lead levels in drinking water, it is recommended that when water utility plans for water main renewal project, it considers working with property owners to replace lead service lines as part of the project. | https://en.wikipedia.org/wiki?curid=61988019 |
Chloromethcathinone may refer to: | https://en.wikipedia.org/wiki?curid=61989431 |
Timeline of events related to per- and polyfluoroalkyl substances This timeline of events related to per- and polyfluoroalkyl substances (PFASs) includes events related to the discovery, development, manufacture, marketing, uses, concerns, litigation, regulation, and legislation, involving the man-made PFASs, particularly perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS). and about the companies, mainly DuPont and 3M that manufactured and marketed them. Perfluorinated compounds are a group of hundreds of man-made compounds collectively known" as PFAS. Fluorosurfactants (PFAS) have been produced and marketed by DuPont under its trademark Teflon—a fluorinated polymer. PFAS compounds and their derivatives are widely used in many products from water resistant textiles to fire-fighting foam. A replacement for PFOAs and PFOS—GenX chemicals and PFBS—are "man-made, fluorinated organic chemicals that are part of the larger group —per- and polyfluoroalkyl substances (PFAS). PFAS are commonly found in every American household, and in products as diverse as non-stick cookware, stain resistant furniture and carpets, wrinkle free and water repellant clothing, cosmetics, lubricants, paint, pizza boxes, popcorn bags, and many other everyday products. The backbone of polytetrafluoroethylene and related chemicals is the fluorocarbon chain. | https://en.wikipedia.org/wiki?curid=61990312 |
Compounds of aluminium Aluminium (or aluminum) combines characteristics of pre- and post-transition metals. Since it has few available electrons for metallic bonding, like its heavier group 13 congeners, it has the characteristic physical properties of a post-transition metal, with longer-than-expected interatomic distances. Furthermore, as Al is a small and highly charged cation, it is strongly polarizing and aluminium compounds tend towards covalency; this behaviour is similar to that of beryllium (Be), an example of a diagonal relationship. However, unlike all other post-transition metals, the underlying core under aluminium's valence shell is that of the preceding noble gas, whereas for gallium and indium it is that of the preceding noble gas plus a filled d-subshell, and for thallium and nihonium it is that of the preceding noble gas plus filled d- and f-subshells. Hence, aluminium does not suffer the effects of incomplete shielding of valence electrons by inner electrons from the nucleus that its heavier congeners do. Aluminium's electropositive behavior, high affinity for oxygen, and highly negative standard electrode potential are all more similar to those of scandium, yttrium, lanthanum, and actinium, which have ds configurations of three valence electrons outside a noble gas core: aluminium is the most electropositive metal in its group | https://en.wikipedia.org/wiki?curid=61997772 |
Compounds of aluminium Aluminium also bears minor similarities to the metalloid boron in the same group; AlX compounds are valence isoelectronic to BX compounds (they have the same valence electronic structure), and both behave as Lewis acids and readily from adducts. Additionally, one of the main motifs of boron chemistry is regular icosahedral structures, and aluminium forms an important part of many icosahedral quasicrystal alloys, including the Al–Zn–Mg class. Aluminium reacts with most nonmetals upon heating, forming compounds such as aluminium nitride (AlN), aluminium sulfide (AlS), and the aluminium halides (AlX). It also forms a wide range of intermetallic compounds involving metals from every group on the periodic table. Aluminium has a high chemical affinity to oxygen, which renders it suitable for use as a reducing agent in the thermite reaction. A fine powder of aluminium metal reacts explosively on contact with liquid oxygen; under normal conditions, however, aluminium forms a thin oxide layer that protects the metal from further corrosion by oxygen, water, or dilute acid, a process termed passivation. This layer is destroyed by contact with mercury due to amalgamation or with salts of some electropositive metals. As such, the strongest aluminium alloys are less corrosion-resistant due to galvanic reactions with alloyed copper, and aluminium's corrosion resistance is greatly reduced by aqueous salts, particularly in the presence of dissimilar metals | https://en.wikipedia.org/wiki?curid=61997772 |
Compounds of aluminium In addition, although the reaction of aluminium with water at temperatures below 280 °C is of interest for the production of hydrogen, commercial application of this fact has challenges in circumventing the passivating oxide layer, which inhibits the reaction, and in storing the energy required to regenerate the aluminium metal. Primarily because it is corroded by dissolved chlorides, such as common sodium chloride, household plumbing is never made from aluminium. However, because of its general resistance to corrosion, aluminium is one of the few metals that retains silvery reflectance in finely powdered form, making it an important component of silver-colored paints. Aluminium mirror finish has the highest reflectance of any metal in the 200–400 nm (UV) and the 3,000–10,000 nm (far IR) regions; in the 400–700 nm visible range it is slightly outperformed by tin and silver and in the 700–3000 nm (near IR) by silver, gold, and copper. In hot concentrated hydrochloric acid, aluminium reacts with water with evolution of hydrogen, and in aqueous sodium hydroxide or potassium hydroxide at room temperature to form aluminates—protective passivation under these conditions is negligible. The reaction with aqueous alkali is often written: although the aluminium species in solution is probably instead the hydrated tetrahydroxoaluminate anion, [Al(OH)] or [Al(HO)(OH)] | https://en.wikipedia.org/wiki?curid=61997772 |
Compounds of aluminium Oxidizing acids do not effectively attack high-purity aluminium because the oxide layer forms and protects the metal; aqua regia will nevertheless dissolve aluminium. This allows aluminium to be used to store reagents such as nitric acid, concentrated sulfuric acid, and some organic acids. The vast majority of compounds, including all aluminium-containing minerals and all commercially significant aluminium compounds, feature aluminium in the oxidation state 3+. The coordination number of such compounds varies, but generally Al is either six- or four-coordinate. Almost all compounds of aluminium(III) are colorless. In aqueous solution, Al exists as the hexaaqua cation [Al(HO)], which has an approximate pK of 10. Such solutions are acidic as this cation can act as a proton donor, progressively hydrolysing to [Al(HO)(OH)], [Al(HO)(OH)], and so on. As pH increases these mononuclear species begin to aggregate together by the formation of hydroxide bridges, forming many oligomeric ions, such as the Keggin ion [AlO(OH)(HO)]. The process ends with precipitation of aluminium hydroxide, Al(OH). This is useful for clarification of water, as the precipitate nucleates on suspended particles in the water, hence removing them. Increasing the pH even further leads to the hydroxide dissolving again as aluminate, [Al(HO)(OH)], is formed | https://en.wikipedia.org/wiki?curid=61997772 |
Compounds of aluminium Aluminium hydroxide forms both salts and aluminates and dissolves in acid and alkali, as well as on fusion with acidic and basic oxides: This behaviour of Al(OH) is termed amphoterism, and is characteristic of weakly basic cations that form insoluble hydroxides and whose hydrated species can also donate their protons. Further examples include Be, Zn, Ga, Sn, and Pb; indeed, gallium in the same group is slightly more acidic than aluminium. One effect of this is that aluminium salts with weak acids are hydrolysed in water to the aquated hydroxide and the corresponding nonmetal hydride: aluminium sulfide yields hydrogen sulfide, aluminium nitride yields ammonia, and aluminium carbide yields methane. Aluminium cyanide, acetate, and carbonate exist in aqueous solution but are unstable as such; only incomplete hydrolysis takes place for salts with strong acids, such as the halides, nitrate, and sulfate. For similar reasons, anhydrous aluminium salts cannot be made by heating their "hydrates": hydrated aluminium chloride is in fact not AlCl·6HO but [Al(HO)]Cl, and the Al–O bonds are so strong that heating is not sufficient to break them and form Al–Cl bonds instead: All four trihalides are well known. Unlike the structures of the three heavier trihalides, aluminium fluoride (AlF) features six-coordinate aluminium, which explains its involatility and insolubility as well as high heat of formation | https://en.wikipedia.org/wiki?curid=61997772 |
Compounds of aluminium Each aluminium atom is surrounded by six fluorine atoms in a distorted octahedral arrangement, with each fluorine atom being shared between the corners of two octahedra in a structure related to but distorted from that of ReO. Such {AlF} units also exist in complex fluorides such as cryolite, NaAlF, but should not be considered as [AlF] complex anions as the Al–F bonds are not significantly different in type from the other M–F bonds. Such differences in coordination between the fluorides and heavier halides are not unusual, occurring in Sn and Bi as well for example; even bigger differences occur between CO and SiO. AlF melts at and is made by reaction of aluminium oxide with hydrogen fluoride gas at . With heavier halides, the coordination numbers are lower. The other trihalides are dimeric or polymeric with tetrahedral four-coordinate aluminium centers. Aluminium trichloride (AlCl) has a layered polymeric structure below its melting point of , but transforms on melting to AlCl dimers with a concomitant increase in volume by 85% and a near-total loss of electrical conductivity. These still predominate in the gas phase at low temperatures (150–200 °C), but at higher temperatures increasingly dissociate into trigonal planar AlCl monomers similar to the structure of BCl. Aluminium tribromide and aluminium triiodide form AlX dimers in all three phases and hence do not show such significant changes of properties upon phase change. These materials are prepared by treating aluminium metal with the halogen | https://en.wikipedia.org/wiki?curid=61997772 |
Compounds of aluminium The aluminium trihalides form many addition compounds or complexes; their Lewis acidic nature makes them useful as catalysts for the Friedel–Crafts reactions. Aluminium trichloride has major industrial uses involving this reaction, such as in the manufacture of anthraquinones and styrene; it is also often used as the precursor for many other aluminium compounds and as a reagent for converting nonmetal fluorides into the corresponding chlorides (a transhalogenation reaction). Aluminium forms one stable oxide with the chemical formula AlO, commonly called alumina. It can be found in nature in the mineral corundum, α-alumina; there is also a γ-alumina phase. As corundum is very hard (Mohs hardness 9), has a high melting point of , has very low volatility, is chemically inert, and a good electrical insulator, it is often used in abrasives (such as toothpaste), as a refractory material, and in cermanics, as well as being the starting material for the electrolytic production of aluminium metal. Sapphire and ruby are impure corundum contaminated with trace amounts of other metals. The two main oxide-hydroxides, AlO(OH), are boehmite and diaspore. There are three main trihydroxides: bayerite, gibbsite, and nordstrandite, which differ in their crystalline structure (polymorphs). Many other intermediate and related structures are also known. Most are produced from ores by a variety of wet processes using acid and base. Heating the hydroxides leads to formation of corundum | https://en.wikipedia.org/wiki?curid=61997772 |
Compounds of aluminium These materials are of central importance to the production of aluminium and are themselves extremely useful. Some mixed oxide phases are also very useful, such as spinel (MgAlO), Na-β-alumina (NaAlO), and tricalcium aluminate (CaAlO, an important mineral phase in Portland cement). The only stable chalcogenides under normal conditions are aluminium sulfide (AlS), selenide (AlSe), and telluride (AlTe). All three are prepared by direct reaction of their elements at about and quickly hydrolyse completely in water to yield aluminium hydroxide and the respective hydrogen chalcogenide. As aluminium is a small atom relative to these chalcogens, these have four-coordinate tetrahedral aluminium with various polymorphs having structures related to wurtzite, with two-thirds of the possible metal sites occupied either in an orderly (α) or random (β) fashion; the sulfide also has a γ form related to γ-alumina, and an unusual high-temperature hexagonal form where half the aluminium atoms have tetrahedral four-coordination and the other half have trigonal bipyramidal five-coordination. Four pnictides, aluminium nitride (AlN), aluminium phosphide (AlP), aluminium arsenide (AlAs), and aluminium antimonide (AlSb), are known. They are all III-V semiconductors isoelectronic to silicon and germanium, all of which but AlN have the zinc blende structure. All four can be made by high-temperature (and possibly high-pressure) direct reaction of their component elements | https://en.wikipedia.org/wiki?curid=61997772 |
Compounds of aluminium Although the great majority of aluminium compounds feature Al centers, compounds with lower oxidation states are known and are sometimes of significance as precursors to the Al species. AlF, AlCl, AlBr, and exist in the gaseous phase when the respective trihalide is heated with aluminium, and at cryogenic temperatures. Their instability in the condensed phase is due to their ready disproportionation to aluminium and the respective trihalide: the reverse reaction is favored at high temperature (although even then they are still short-lived), explaining why AlF is more volatile when heated in the presence of aluminium metal, as is aluminium metal when heated in the presence of AlCl. A stable derivative of aluminium monoiodide is the cyclic adduct formed with triethylamine, . Also of theoretical interest but only of fleeting existence are AlO and AlS. AlO is made by heating the normal oxide, AlO, with silicon at in a vacuum. Such materials quickly disproportionate to the starting materials. Very simple Al(II) compounds are invoked or observed in the reactions of Al metal with oxidants. For example, aluminium monoxide, AlO, has been detected in the gas phase after explosion and in stellar absorption spectra. More thoroughly investigated are compounds of the formula RAl which contain an Al–Al bond and where R is a large organic ligand. A variety of compounds of empirical formula AlR and AlRCl exist. The aluminium trialkyls and triaryls are reactive, volatile, and colorless liquids or low-melting solids | https://en.wikipedia.org/wiki?curid=61997772 |
Compounds of aluminium They catch fire spontaneously in air and react with water, thus necessitating precautions when handling them. They often form dimers, unlike their boron analogues, but this tendency diminishes for branched-chain alkyls (e.g. Pr, Bu, MeCCH); for example, triisobutylaluminium exists as an equilibrium mixture of the monomer and dimer. These dimers, such as trimethylaluminium (AlMe), usually feature tetrahedral Al centers formed by dimerization with some alkyl group bridging between both aluminium atoms. They are hard acids and react readily with ligands, forming adducts. In industry, they are mostly used in alkene insertion reactions, as discovered by Karl Ziegler, most importantly in "growth reactions" that form long-chain unbranched primary alkenes and alcohols, and in the low-pressure polymerization of ethene and propene. There are also some heterocyclic and cluster organoaluminium compounds involving Al–N bonds. The industrially most important aluminium hydride is lithium aluminium hydride (LiAlH), which is used in as a reducing agent in organic chemistry. It can be produced from lithium hydride and aluminium trichloride: The simplest hydride, aluminium hydride or alane, is not as important. It is a polymer with the formula (AlH), in contrast to the corresponding boron hydride that is a dimer with the formula (BH). | https://en.wikipedia.org/wiki?curid=61997772 |
Discovery and development of bisphosphonates Bisphosphonates are an important class of drugs originally introduced about half a century ago. They are used for the treatment of osteoporosis and other bone disorders that cause bone fragility and diseases where bone resorption is excessive. Osteoporosis is common in post-menopausal women and patients in corticosteroid treatment where biphosphonates have been proven a valuable treatment and also used successfully against Paget's disease, myeloma, bone metastases and hypercalcemia. Bisphosphonates reduce breakdown of bones by inhibiting osteoclasts, they have a long history of use and today there are a few different types of bisphosphonate drugs on the market around the world. Bisphosphonates were originally synthesized in the 19th century and used in industry for their antiscaling and anticorrosive properties. In the late 1960s their potential to treat diseases related to the metabolism of the bones became evident. The first generation of bisphosphonates included etidronic acid and clodronic acid which were introduced in the 1970s and 1980s. They were the first bisphosphonate drugs to be used successfully in the clinic. They have since then been developed further with the intention to make them more potent, enhance their distribution inside the bone and extend the duration of action. This has made it possible to give zoledronate, the most recent bisphosphonate drug to be placed on the market, in a single annual dose by intravenous infusion | https://en.wikipedia.org/wiki?curid=61997982 |
Discovery and development of bisphosphonates The original bisphosphonates (first generation) were simple molecules with small groups of single atoms or alkyl chains in position R and R. They only had a rather weak inhibiting effect on bone resorption. The inclusion of an amino group marked the beginning of the second generation of bisphosphonates with higher potency. The first was pamidronate and similar analogues followed where the position of the nitrogen in the side chain was the key to a more potent drug. Later it became apparent that the nitrogen does not necessarily have to be connected to an alkyl chain but instead using a heterocyclic group. A few such drugs have been developed and placed on the market where zoledronate is the most notable one. Minodronic acid is even more potent and has been placed on the market in Japan. Their potency is such that it is effective even in picomolar concentration. Further development has not resulted in the placing on the market of compounds in equal potency. Arylalkyl substitutes of pamidronate are among the most recent bisphosphonates to be used clinically where the hydroxyl group in position R has been omitted to ensure stability. Recent research in this area has opened up an opportunity to develop new bisphosphonate drug therapies. Bisphosphonates with a more lipophilic character have been developed and have shown potential as a tumor suppressant | https://en.wikipedia.org/wiki?curid=61997982 |
Discovery and development of bisphosphonates They operate by a slightly different mechanism in which they not only inhibit the key enzyme farnesyl pyrophosphate synthase (FPPS) of the mevalonate pathway but also geranylgeranyl pyrophosphate synthase (GGPS), an enzyme also located in the mevalonate pathway. They do not have the same affinity for the bone minerals. GGPS has since been successfully inhibited by a novel bisphosphonate compound with a triazole group within R and a methyl group in R. This may become useful in therapies against malignancies like multiple myeloma. In 2018, a dendritic bisphosphonate was introduced containing three bisphosphonate units. It has shown potential for bone specific delivery of large therapeutic molecules by taking advantage of the high affinity of bisphosphonates to the bone minerals The mechanism of action of the bisphosphonates (BP´s) has evolved as new generations of drugs have been developed. The function of the first generation bisphosphonates differs from the more recent nitrogen containing BP´s but both are apparently internalised by endocytosis of a membrane-bound vesicle where the drug is most likely in a complex with Ca ions. This does not concern other cells in the bone as this takes places by a selective uptake of osteoclasts. The common function which applies to all bisphosphonate drugs is a physicochemical interaction with the bone mineral to prevent the physical resorption of the bone by the osteoclasts. This is especially relevant at sites where bone remodelling is most active | https://en.wikipedia.org/wiki?curid=61997982 |
Discovery and development of bisphosphonates The bisphosphonates have an intrinsic affinity for the calcium ions (hydroxyapatite) of the bone mineral just as the endogenous pyrophosphates. The difference lies in the non-hydrolysable carbon-phosphorus bond of the bisphosphonates which prevents their metabolism and at the same time ensure an effective absorption from the gastrointestinal tract. The primary inhibiting action of the first generation of bisphosphonates on osteoclasts is by inducing apoptosis. The mechanism of action is apparently by the formation of an ATP analogue or metabolite of the bisphosphonates like etidronic acid and clodronic acid. The ATP analogue accumulates in the cytosol of the osteoclast with a cytotoxic effect. The primary mechanism of action of the more developed nitrogen containing bisphosphonates is however by cellular effects on osteoclasts through inhibition of the mevalonate pathway and in particular the subsequent formation of isoprenoid lipids. The inhibition takes place at a key branch point in the pathway catalyzed by farnesyl pyrophosphate synthase (FPPS). Isoprenoid lipids are necessary for post-translational modifications of small GTP-binding regulatory proteins like Rac, Rho and Ras of the Ras superfamily. The function of osteoclasts depends on them for a variety of cellular processes like apoptosis. Bisphosphonates mimic the endogenous inorganic pyrophosphate where the oxygen backbone is replaced with carbon (P-C-P for P-O-P) | https://en.wikipedia.org/wiki?curid=61997982 |
Discovery and development of bisphosphonates The two additional groups or side chains on the carbon backbone are usually referred to as R and R. R is usually a hydroxyl group which enhances the affinity for the calcium by forming a tridentate ligand along with the phosphate groups. The compound can be made more potent by optimizing the structure of the R group to best inhibit bone resorption. Phosphonate groups in the chemical structure are important for the binding of the drug to the target enzyme. Studies have showed that removal or replacement of the phosphonate group with a carboxylic acid causes drastic loss in potency of the drug and the enzyme inhibitor no longer goes into an isomerized state. Modification of the R side chain on bisphosphonates is very minor today, single hydroxyl group at that position seems to give the best results in terms of activity. The hydroxyl group plays a role in forming a water-induced bond with glutamine (Gln240) on the target enzyme. Drugs that have no hydroxyl group initially cause better inhibition than parent compounds, without hydroxyl group the drug seems to fit more easily into the open active site. The absence of hydroxyl group however reduces the ability to hold the target enzyme complex in isomerized state. Biological activity of bisphosphosnates with hydroxyl group therefore appears over longer time. Nitrogen containing bisphosphonates are the current most used drugs in the class because of their potency | https://en.wikipedia.org/wiki?curid=61997982 |
Discovery and development of bisphosphonates Studies have showed that nitrogen on bisphosphonates forms hydrogen bond with threonine (Thr201) and the carbonyl part of Lysine (Lys200) on target enzyme, therefore enhancing the binding of the complex. Altering the position of nitrogen can significantly change the ability for the nitrogen hydrogen bond to occur. Increased carbon length of the nitrogen R side chain alters activity. Side chain that is made out of three carbons has proven to be the most ideal length in terms of activity, increasing or decreasing the length of the chain from there has negative effect on biological activity. Alendronate, a common bisphosphonate drug, has a three carbon length side chain for example. Risedronate has heterocyclic structure containing nitrogen. Heterocyclic nitrogen containing bisphosphonates have revealed better results in terms of activity compared to earlier bisphosphonates with nitrogen bound to carbon chain. Studies on risedronate analogous with different placement of nitrogen on the ring have shown no measurable difference on biological activity. Increased length of carbon chain connected to the ring revealed negative results. Zoledronate is the most potent bisphosphonate drug today only available as intravenous injection. It is the only bisphosphonate drug that has two nitrogen groups in the side chain hence it's potency and route of administration differs from other drugs in the same class. | https://en.wikipedia.org/wiki?curid=61997982 |
Pyrogallolarenes A pyrogallolarene (also calix[4]pyrogallolarene) is a macrocycle, or a cyclic oligomer, based on the condensation of pyrogallol (1,2,3-trihydroxybenzene) and an aldehyde. are a type of calixarene, and a subset of resorcinarenes that are substituted with a hydroxyl at the 2-position. Pyrogallolarenes, like all resorcinarenes, form inclusion complexes with other molecules forming a host–guest complex. (like resorcinarenes) self-assemble into larger supramolecular structures forming a hydrogen-bonded hexamer. The pyrogallolarene hexamer is unique from those formed from resorcinarene, in that it does not incorporate solvent molecules into the structure. Both in the crystalline state and in organic solvents, six molecules will form an assembly with an internal volume of around one cubic nanometer (nanocapsules) and shapes similar to the Archimedean solids. A number of solvent or other molecules may reside in the capsule interior. The pyrogallolarene hexamer is generally more stable than the resorcinarene hexamer, even in polar solvents. The pyrogallolarene macrocycle is typically prepared by condensation of pyrogallol and an aldehyde in concentrated acid solution in the presence of an alcohol solvent, usually methanol or ethanol. The reaction conditions can usually be carefully adjusted to precipitate the pure product or the product may be purified by recrystallization. | https://en.wikipedia.org/wiki?curid=61999316 |
Junqiao Wu is a professor of materials science at the University of California, Berkeley. Wu's materials science research focuses on thermal energy. Wu's research in semiconductors has led to the discovery that electrons in vanadium dioxide conduct energy without conducting heat. | https://en.wikipedia.org/wiki?curid=62011298 |
Peter Ventzek (1964–) is an engineer. In 2006 he received the NOGLSTP GLBT engineer award for outstanding contributions to the semiconductor industry. Ventzek was born in Columbus, Georgia in 1964. He received B.S. in Chemical Engineering from the University of New Brunswick and his PhD in Nuclear Engineering from the University of Michigan. His graduate research with Professor Ronald Gilgenbach dealt with the dynamics of laser ablation plasmas for materials processing. As a post-doctoral researcher at the University of Illinois, Ventzek developed a multi-dimensional computer platform for plasma sources for material processing. In 1994, Ventzek joined Hokkaido University in Japan as Associate Professor in the Department of Electrical Engineering. His research dealt with plasma process control, laser ablation, neutral beam sources and atmospheric pressure discharges. In 1997, Ventzek joined Motorola/Freescale to direct the development of integrated computational platforms for plasma etching and deposition. Ventzek has published over 60 journal articles. Ventzek was Chair of the American Vacuum Society's Plasma Science and Technology Division, Chair of the GEC, and a professor at Keio University. Ventzek's work has been cited a number of times. In 1994, Peter Ventzek, together with Dr. Mark Kushner, Seung Choi, and Robert Hoekstra, received the Technical Excellence Award for research at the University of Illinois at Urbana-Champaign on computer modeling of plasma reactors | https://en.wikipedia.org/wiki?curid=62011929 |
Peter Ventzek In 2006, Ventzek received NOGLSTP GLBT Engineer Award, which recognizes a GLBT Engineer who has made outstanding contributions in their field. This award honors Ventzek's contributions to improvements in the semiconductor industry as well as his support of GLBT employees at Freescale. In 2013, Ventzek received the plasma science and technology award for outstanding contributions to the field granted by the American Vacuum Society. | https://en.wikipedia.org/wiki?curid=62011929 |
Nanolattice A nanolattice is a synthetic porous material consisting of nanometer-size members which are patterned into an ordered lattice structure, like a space frame. Driven by the evolution of 3D printing techniques, nanolattices aiming to exploit beneficial material size effects through miniaturized lattice designs were first developed in the mid-2010s. Nanolattices are the smallest man-made lattice truss structures and a class of metamaterials which derive their properties from both their geometry (general metamaterial definition) and the small size of their elements. Therefore, they can possess effective properties which are not found in nature and may not be achieved with larger-scale lattices of the same geometry. To produce nanolattice materials, polymer templates are manufactured by high-resolution 3D printing processes, such as multiphoton lithography, or by self-assembly techniques. Ceramic, metal or composite material nanolattices are formed by post-treatment of the polymer templates with techniques including pyrolysis, atomic layer deposition, electroplating and electroless plating. Pyrolysis, which additionally shrinks the lattices by up to 90%, creates the smallest-size structures, whereby the polymeric template material transforms into carbon, or other ceramics and metals, through thermal decomposition in inert atmosphere or vacuum. Nanolattices are the strongest existing cellular materials, they are extremely light-weight, consisting of 50%-99% air, but can be as strong as steel | https://en.wikipedia.org/wiki?curid=62013142 |
Nanolattice The extremely small volume of their individual members thereby statistically nearly eliminates the material flaw population and the base material of nanolattices can reach mechanical strengths on the order of the theoretical strength of an ideal, perfect crystal. While such effects are typically limited to individual, geometrically primitive structures like nanowires, the specific architecture allows nanolattices to exploit them in complex, three-dimensional structures of notably larger overall size. Nanolattices can be designed highly deformable and recoverable, even with ceramic base materials, and can possess mechanical metamaterial properties like auxetic or meta-fluidic behavior. Nanolattices can combine mechanical resilience and ultra-low thermal conductivity and can have electromagnetic metamaterial characteristics like optical cloaking. | https://en.wikipedia.org/wiki?curid=62013142 |
Strasbourg Institute of Material Physics and Chemistry The (IPCMS—) is a joint research unit between the French National Center for Scientific Research (CNRS) and the University of Strasbourg. It was founded in 1987 and is located in the district of Cronenbourg in Strasbourg, France. The IPCMS was born from a reflection initiated in the early eighties on the need to refocus and coordinate research in the physics and chemistry of condensed matter and materials. In the context of the then emerging Materials Center in Strasbourg, a first reorganization project for condensed matter physics was formalized in 1983. Then, in the same years, the strategic importance of materials for innovation is recognized, justifying the extension of the initial project to chemists, to constitute the backbone of the future institute by bringing together physicists and chemists on the objective of designing and studying new materials (metals, ceramics, ...) for their electronic properties (magnetic, optical, dielectric, etc.). CNRS-ULP-EHICS joint unit, the IPCMS is officially created in 1987 with François Gautier as Director and Jean-Claude Bernier as Deputy Director. Originally located on five different sites of the University of Strasbourg, it was in 1994 that members of the IPCMS were grouped together in the current building on the Campus of Cronenbourg | https://en.wikipedia.org/wiki?curid=62015338 |
Strasbourg Institute of Material Physics and Chemistry The IPCMS is then organized into five research groups around three types of materials - polymers and organic materials, metallic materials, ceramics and inorganic materials - and two topics of study: nonlinear optics and optoelectronics on one hand, surfaces and interfaces on the other hand. The multi-disciplinary nature of the IPCMS is expressed by leading activities in spin electronics, magnetism, ultra-fast optics, electron microscopy and local probes, biomaterials as well as in the synthesis and characterization of functional organic, inorganic or hybrid materials. All scales are considered from the isolated molecule to organized nanostructures on surfaces and single or two-dimensional objects, up to nano-devices. To carry out these studies, the institute has an important instrumental park for the fabrication and characterization of materials at all scales. The developments are also based on recognized theoretical skills. The projects LabEX NIE and EquipEX UNION and UTEM that the IPCMS directs reflect the recognized position of the laboratory. Located on the Campus of Cronenbourg, IPCMS is affiliated with the institutes of physics and chemistry of the CNRS as well as the Faculty of Physics and Engineering, it is also affiliated with the European School of Chemistry, Polymers and Materials (ECPM), Télécom Physique Strasbourg, and the Faculty of Chemistry of the University of Strasbourg | https://en.wikipedia.org/wiki?curid=62015338 |
Strasbourg Institute of Material Physics and Chemistry The IPCMS is very attached to maintain strong links with the industrial laboratories carrying out research in its fields of competence. The IPCMS now employs a staff of 240 including about 80 researchers and teacher-researchers and 60 technical and administrative engineers, whose activities are divided into five departments: Department pages: | https://en.wikipedia.org/wiki?curid=62015338 |
Betty Sullivan Betty Julia Sullivan (31 May 1902 — 25 December 1999) was an American biochemist between the 1920s and 1940s at Russell Miller Milling Company. In 1947, Sullivan began her executive career as research director and vice-president for Russell Miller until the company became part of Peavey Company in 1958. After the merger, Sullivan remained in her executive roles before leaving in 1967 to co-start an agribusiness consulting company. While working at Experience Inc, Sullivan became director of the company in 1975 and retired in 1992. During her career, Sullivan was the first woman recipient of the Osbourne Medal upon receiving the medal by the American Association of Cereal Chemists in 1948. Years later, Sullivan was awarded the Garvan–Olin Medal from the American Chemical Society in 1954. On May 31, 1902, Sullivan was born in Minneapolis, Minnesota. Sullivan attended the University of Minnesota for her Bachelor of Science in 1922. In the mid 1920s, Sullivan left the United States and completed a master's degree at the University of Paris in 1925. The following year, she conducted research at the Pasteur Institute in 1926. In 1935, Sullivan returned to the University of Minnesota for a Doctor of Philosophy in biochemistry and a minor degree in organic chemistry. Sullivan wrote her Bachelor of Science thesis on the chemical reactions in pinene and her PhD thesis about the lipids found in wheat. In 1922, Sullivan started her chemistry career as a lab assistant for the Russell Miller Milling Company in 1922 | https://en.wikipedia.org/wiki?curid=62018822 |
Betty Sullivan While at Russell Miller, Sullivan was promoted to head chemist in 1927 and research director in 1947. While researching the food chemistry of wheat and flour, Sullivan simultaneously held the position of vice-president. After Russell Miller became a part of Peavey Company in 1958, Sullivan continued her research and executive positions with Peavey while worked in food processing to create new products. When Sullivan left Peavey in 1967, she co-created an agribusiness consulting company called Experience Inc. During her time with Experience Inc. Sullivan held various positions including president in 1969 and director in 1975 before her 1992 retirement. In 1948, Sullivan became the first woman to be awarded the Osbourne Medal by the American Association of Cereal Chemists. Sullivan was also awarded the Garvan–Olin Medal in 1954 by the American Chemical Society. On 25 December 1999, Sullivan died in Bloomington, Minnesota. | https://en.wikipedia.org/wiki?curid=62018822 |
Microcracks in rock Microcracks in rock, also known as microfractures and cracks, are spaces in rock with the longest length of 1000 μm and the other two dimensions of 10 μm. In general, the ratio of width to length of microcracks is between 10 to 10. Due to the scale, microcracks are observed using microscope to obtain their basic characteristics. Microcrack formation provides insights into the strength and deformation behavior of rocks. Experimental and numerical results both play an important role in studying microcracks, especially their kinematics and dynamics.have been studied to understand geologic problems such as the early stage of earthquakes and fault formation. In engineering, microcracks in rock have been linked to underground engineering problems, such as deep geological repository. In general, microcracks in rock can be subdivided into four groups: The characteristics of microcracks are orientation, length, width, aspect ratio, number, and density. These characteristics have been tried to be explained by mathematical functions. For example, distribution of microcrack lengths away from the fault has been described by lognormal or exponential distributions. The orientations of microcracks are random in unstressed rock. Once a rock has been stressed, the microcracks will have a trend of orientations more or less parallel to the maximum applied stress or the fault strike. For example, the average orientation of microcracks of stressed Westerly granite is 30° to the fault strike | https://en.wikipedia.org/wiki?curid=62020761 |
Microcracks in rock In a thin section, the observed length and width may not necessarily be the true length and width of a microcrack in three dimensions. The aspect ratio is the ratio of width to length. It is generally10 to 10. The crack length increases with increasing maximum applied stress, resulting in a decrease in the aspect ratio. Density of microcracks can be either the number of microcracks per unit area or per grain or the microcrack length per unit area. Densities of microcracks near a fault are dramatically high, but they decrease rapidly within a few mineral grains away from a fault. can be induced by the applied stress or temperature. A microcrack is formed when the stresses exceed the local strength of grains. The strength of materials is the ability to resist an applied load so that failure will not occur. The intrinsic properties of rock such as mineralogical heterogeneity give diverse types of mechanically induced microcracking. The following mechanisms have strong correlations to the locations that allow stress concentration in grain-scale. Thermally induced microcracking refers to microcrack formation due to thermal effects. Heating or cooling can cause thermal expansion or contraction between grains, respectively. Minerals with different thermo-elastic properties have different reactions to cooling or heating, resulting in microcrack formation. Also, thermal gradients at internal boundaries of grains may also allow stress concentration, thus forming microcracks | https://en.wikipedia.org/wiki?curid=62020761 |
Microcracks in rock The evolution of microcracks has been studied through experiment. When force is applied to a rock sample, microcracks initially form randomly in space. They then become more and more localized and intense with continuous loading. This phenomenon is called the crack localization. A thoery of failure helps to explain the evolution of microcracks with increased loading: After failure, the overall microcrack density increases near the fault and decreases rapidly away from the fault. In addition, the density of transgranular cracks increases near the fault, whereas the density of grain boundary cracks is lower. Connecting locally dense crack regions, crack arrays, and grain boundary eventually forms a macrocrack. Before forming a fault, there is a fracture process zone (FPZ). It is a region of microcracks near the tip of a rock failure. It is associated with the crack localization and related to energy dissipation. The size of a fracture process zone is related to the specimen size. The larger the specimen size, the large the size of the fracture process zone. This relationship no longer exists when the specimen size is larger than a certain size. The heterogeneity of rock makes the microcracking behavior much more complicated than other simple materials. Factors controlling microcracking behavior still have been identified and studied: In addition to microcracks formation, microcracks in rock can be recovered either by microcrack closure or microcrack healing | https://en.wikipedia.org/wiki?curid=62020761 |
Microcracks in rock Microcrack recovery will direclty cause a decrease in permeability of rock. It can be either caused by increase in the applied stress or decrease in the effective stress. For example, microcracks perpendicular to the maximum stress direction will close. However, in nature, parts of a microcrack can be in different directions. For this reason, it will result in incomplete closure that some parts of the microcrack are closed while some parts are still open. It is driven by transportation of chemical fluid in microcracks. For example, healing of microcracks in quartz is activated by temperature. Healing in quartz becomes fast when the temperature is above 400 °C. The rate of healing also depends on the crack sizes. The smaller the cracks, the faster the healing. Microcracks affect the properties of rock including stiffness, strength, elastic modulus, permeability, fracture toughness, and elastic wave velocity. Studies of microcracks are focused on their distributions of the characteristics and microcracking behavior. Many experiments to study microcracks in rock have been conducted in the past decades, whereas numerical study also has been widely used to study microcracks in recent years because of the technology development. These studies have been used to compare with natural conditions. Experimental study is to analyze the rock specimens that have been subjected to applied stress in laboratory. There are two popular methods to study microcracks | https://en.wikipedia.org/wiki?curid=62020761 |
Microcracks in rock Observation of thin section using microscope is to obtain the distributions of microcrack lengths, widths and aspect ratios, numbers and densities, as well as orientations. Another method is using acoustic emission to detect and monitor microcrack growth. Experimental results can help scientists develope numerical models, such as simulation of fracture pattern growth. Many experiments on rock fracture mechanism have been done in laboratory, but these experiments may have different requirement of specimen configuration and loading scheme. They are the two important factors controlling microcracking behavior such as microcrack development. Specimen configuration refers to the dimensions of a specimen and its man-made crack. Rock samples are usually obtained from rock cores. Therefore, cylinder shape, chevron-bend shape, and semi-circular-bend shape (SCB) are the common specimen shapes used in experimental study. For example, a semi-circular bend specimen has a man-made crack, called a notch. It is used to control the morphology of rock fracture. Two notch types can be induced: a straight-through notch or a chevron notch. A straight-through notch semi-circular-bend (SNCCB) specimen has a flat-ended notch, whereas a chevron notch semi-circular-bend (CNSCB) specimen has a V-shaped opening to the air. In fracture mechanics, there are three types of loading modes to make a crack able to propagate. They are mode I (opening), mode II (in-plane shear), and mode III (out-plane shear) | https://en.wikipedia.org/wiki?curid=62020761 |
Microcracks in rock These loading modes can be achieved by the designed loading scheme. Mode I fractures are the most common microcracks in rock in natural. An acoustic emission (AE) is a high-frequency elastic wave. It is generated from microcrack formations, and is corelated to rapid microcrack growth. Acoustic emission sensors are attached to the surface of the specimen. They collect the signals generated during microcrack formation. The data can be used to describe the microcrack behavior. Noted that one detected acoustic emission event is not necessary to be one microcrack formation. The types of data collected from acoustic emission sensors are: These two types of data imply the following information: Numerical study is used to help understanding the complicated rock mechanics problems. Four types of models using in modelling microcracks in rock are particle-based models, block-based models, grain-based models, and node-based models. Since grain-based models can consider all types of microcrack, they are good at understanding microcracking behavior. Experimental study of microcracks provides insights into faulting and microcracks formation in nature. Microcracks studies with CL and fluid-inclusion studies are able to reconstruct the growth of fractures from microcracks. Population of microcracks is useful to distinguish whether the detachment is due to landslide or tectonic in origin. The fracture process zone (FPZ) can be used to understand the permeability of fault zones which controls fluid flow | https://en.wikipedia.org/wiki?curid=62020761 |
Microcracks in rock Therefore, microcracks can be useful for assessing the stress history or fluid movement history of rock. Acoustic emission from microcrack growth may help to understand earthquakes. Microcracks can affect the thermal and transport properties of rock. Studies of microcracks in rock provide an important insights into underground engineering problems as follows: A deep geological repository is an underound repository for radioactive waste disposal, such as nuclear fuel. It is at depth of hundred metres in a stable rock mass. Deep geological repositories are all over the world, such as the United States (WIPP) and Finland (Olkiluoto Nuclear Power Plant). A geothermal reservoir is one of the three components of a geothermal system that acts an energy source. It is a porous and permeable rock mass so that convection of trapped hot water and steam and recharge of heat supply can occur. The ideal geothermal reservoir is a highly permeable, fractured rock matrix. A hydrocarbon reservoir is an underground reservoir that keeps hydrocarbons trapped inside. Reservoir rocks have high porosity and permeability while the surrounding rocks that act as barriers have low permeability. Therefore, hydrocarbons that exist as liquid and/or gas can only stay in the reservoir rocks. Underground storage of CO is a solution to remove CO in the atmosphere. It is composed of porous rocks surrounded by nonporous rocks so that it can trap the CO for a long time | https://en.wikipedia.org/wiki?curid=62020761 |
Microcracks in rock A depleted oil and gas reservoir that is out of energy source is one of the examples used for underground storage. | https://en.wikipedia.org/wiki?curid=62020761 |
Christian Amatore (born 9 December 1951 in Algeria) is a French chemist and a member of the French Academy of Sciences. He is an author of works in electrochemistry. Coming from a modest family (Sicilian by his father, Swedish by his mother), he spent a large part of his childhood in Algeria in several garrison towns of Laghouat, Hain-el-Adjar, Sidi Bel Abbès where his father was an NCO of the Foreign Legion. He followed his father's advice "if you are intelligent but you have no education, you remain mute" and followed brilliant studies in Algeria and then in France where his Blackfoot family was repatriated: first to the Lycée Pascal-Paoli in Corte, then to the Lycée Thiers in Marseille where he completed two years of preparatory classes, and finally to the École normale supérieure (rue d'Ulm - Paris) where he obtained the agrégation de chimie in 1974. At the age of 18, he opted for French nationality. CNRS researcher, following his thesis at the University of Paris-VII, he left for the United States for two years as Assistant Professor in an organometallic chemistry research laboratory where he met Mark Wightman at Indiana University with whom he had a pioneering role in the development of ultramicroelectrodes that he applied in artificial synapses. In 1984, he returned to France to found his laboratory at the ENS and became Director of the Chemistry Department at the ENS in 1997. He held these management functions until 2006. | https://en.wikipedia.org/wiki?curid=62032296 |
C29H52 The molecular formula CH may refer to: | https://en.wikipedia.org/wiki?curid=62033048 |
Parascorodite (FeAsO·2HO) is a rare, secondary iron-arsenate mineral. It was discovered in 1967 using X-ray powder diffraction methods, when an unknown substance was found along with scorodite on medieval ore dumps in the Czech Republic. The holotype of parascorodite can be found in the mineralogical collection of the National Museum, Prague, Czech Republic under acquisition number P1p25/98. occurs at the Kank mine in the Kutna Hora ore district in Central Bohemia, Czech Republic . It is one of the rarest secondary minerals. is found in medieval ore dumps, that were most likely used for silver and polymetallic ore waste. The dumps contain arsenic rich ore, which in medieval times was considered waste. The medieval ore dumps are heavily weathered, but it is assumed that parascorodite, along with other secondary iron arsenates and arsenosulfates, actually formed much before the dumping of waste material on this area by natural weathering processes. formed as a product of arsenopyrite dissolution, followed by recrystallization of iron-arsenic bearing solutions, in near surface weathering conditions. is dimorphous with scorodite, and is also associated with pitticite, gypsum, jarosite, and amorphous ferric hydroxides. occurs in aggregates of somewhat hemispherical shapes. The aggregates grow to be about 2 cm across, consisting of extremely small crystals that can be arranged in fan-like or irregular masses. is cryptocrystalline, and has a luster that can vary from earthy to vitreous | https://en.wikipedia.org/wiki?curid=62035449 |
Parascorodite It is a soft mineral, falling between 1-2 on the Mohs hardness scale. Aggregates can be white to yellowish, or more rarely green-grey in color, and have a yellow-white streak. The measured density of earthy aggregates in ethyl alcohol is 3.212 g/cm. The rare green-grey variety of parascorodite aggregates may exhibit conchoidal fracture. Individual crystal size varies between 0.1 μm and 0.5 μm, with some twinned crystals measuring 1.0 μm. Crystals occur as either prisms or thin flakes with a hexagonal outline. dissolves slowly in 10% hydrochloric acid (HCl). In water, it will disintegrate rapidly into a powder. Under hydrothermal conditions parascorodite can re-crystallize back to scorodite. The chemical composition of parascorodite was determined using qualitative spectral analysis. Two major elements were indicated: iron and arsenic. Quantitative analysis was also determined using two wet chemical analyses (results in the table below). The crystal structure of parascorodite was determined using x-ray powder diffraction. Using the XRD data (in the table below), the parascorodite unit cell was determined as hexagonal or trigonal. The unit cell parameters are a,a = 8.9327(5)Å, c = 9.9391(8)Å, with a cell volume of V = 686.83(8)Å. | https://en.wikipedia.org/wiki?curid=62035449 |
Adriana Lita Adriana Eleni Lita is a materials scientist. She works in the Faint Photonics Group at the National Institute of Standards and Technology, where her research has included Bell test experiments and the practical implementation of quantum key distribution. She completed a Ph.D. at University of Michigan in 2000. Her dissertation was titled "Correlation between microstructure and surface structure evolution in polycrystalline films". Her doctoral advisor was John E. Sanchez, Jr. | https://en.wikipedia.org/wiki?curid=62064684 |
Leaded copper is a metal alloy of copper with lead. A small amount of lead makes the copper easier to machine. Alloys with a larger amount of lead are used for bearings. Brass and bronze alloys of copper may have lead added and are then also sometimes referred to as leaded copper alloys. and its alloys have been used since ancient times. alloys are used to make electrical connectors and mechanical bearings, especially in the automotive industry where high performance and reliability are required. Mechanical bearings can have high lead content. Such high lead content alloys are unsuitable for welding or brazing. Alloys with around 2-4% lead are used for machined copper applications, where the lead content lubricates the copper and makes it easier to machine. These include high-quality electrical connectors where a high current capacity and low electrical resistance are required. Such connectors are used in industrial automation and the automotive industry. Brasses (copper alloyed with zinc) may also be leaded for the same reason. High-strength casting copper alloys typically contain less than 2% lead. Bearing alloys are often cast or sintered onto a steel backing. Softer alloys with a higher lead content are also used, for example in bushes where conformance to the opposite bearing surface is important. Some casting alloys have over 20% lead content but, due to their toxicity, they are no longer used. When lead alloys wear, lead is released into the environment | https://en.wikipedia.org/wiki?curid=62077237 |
Leaded copper Lead is a heavy metal toxin and in recent times the use of leaded copper alloys has been reduced. Signs of leaded copper use are found in the manufacture of ancient Egyptian faience. By 1500 BC leaded copper could be found across the Old World from East Asia to Africa and Europe. | https://en.wikipedia.org/wiki?curid=62077237 |
Metal–inorganic framework Metal–inorganic frameworks (MIFs) are a class of compounds consisting of metal ions or clusters coordinated to inorganic ligands to form one-, two-, or three-dimensional structures. They are a subclass of coordination polymers, with the special feature that they are often porous. They are inorganic counterpart of Metal–organic frameworks. Millon's base which have been known since early 20th century, can be considered as MIFs. MIF with Borazocine linker was developed for hydrogen storage. Cu2I2Se6 has Se6 linkers. There are many MIFs with pnictogen linkers. | https://en.wikipedia.org/wiki?curid=62086463 |
Marta Catellani is an Italian chemist known for her discovery of the eponymous Catellani reaction in 1997. She was elected to the European Academy of Sciences in 2016. Catellani earned her Ph.D. in chemistry in 1971 from the University of Parma, where, as of 2019, she is a professor and chairs the Department of Organic Chemistry. Catellani completed her postdoctoral education at the University of Chicago. She has served as a visiting professor at Moscow State University (1992), Beijing Institute of Technology (2004), and University of Xi'an (2004). She was awarded a fellowship at the Japan Society for the Promotion of Science in 2012. Her research focuses on palladium as a catalyst for multistep organic reactions. | https://en.wikipedia.org/wiki?curid=62096452 |
Winnie Wong-Ng Winnie Kwai-Wah Wong-Ng () is a Chinese-American physical chemist. She is a research chemist at the ceramics division at the National Institute of Standards and Technology. Her research includes energy applications, crystallography, thermoelectric standards, metrology, and data, sorbent materials for sustainability, and high throughput combinatorial approach for novel materials discovery and property optimization for energy conversion applications. She is a fellow of the International Centre for Diffraction Data, American Ceramic Society, American Crystallographic Association, and the American Association for the Advancement of Science. Wong-Ng was twice awarded the Department of Commerce Bronze Medal. Wong-Ng completed a B.Sc. in chemistry and physics at Chinese University of Hong Kong in 1969. She earned a Ph.D. in inorganic and physical chemistry at Louisiana State University in 1974. Wong-Ng was a research associate and lecturer in the chemistry department at University of Toronto. From 1981 to 1985, she was a critical review scientist at the International Centre for Diffraction Data. Wong-Ng was a research scientist in the chemistry department at University of Maryland, College Park and a research associate in the ceramics division at the National Bureau of Standards from 1985 to 1988. Since 1988, Wong-Ng works as a research chemist in the ceramics division at the National Institute of Standards and Technology. She served as president the Association of NIST Asian Pacific Americans from 2000 to 2003 | https://en.wikipedia.org/wiki?curid=62096903 |
Winnie Wong-Ng Wong-Ng's research interest includes materials for energy applications, thermoelectric standards, metrology, and data, sorbent materials for sustainability, and high throughput combinatorial approach for novel materials discovery and property optimization for energy conversion applications. She also researches crystallography, phase equilibria, and crystal chemistry of energy materials to understand their structure and property relationships. Structural studies involve synchrotron X-ray and neutron diffraction techniques. In 2000, Wong-Ng became a fellow of the International Centre for Diffraction Data (ICDD). She was awarded fellow of the American Ceramic Society in 2002. In 2002 and 2008, she won the Department of Commerce Bronze Medal. In 2014, Wong-Ng was made fellow of the American Crystallographic Association. In 2012, she became a distinguished fellow of the ICDD and a Fellow of the American Association for the Advancement of Science. She became an academician of the World Academy of Ceramics in 2018. | https://en.wikipedia.org/wiki?curid=62096903 |
DFDT Difluorodiphenyltrichloroethane (DFDT) is a chemical compound. Its composition is the same as that of the insecticide DDT, except that two of DDT's chlorine atoms are replaced by two fluorine atoms. was developed as an insecticide by German scientists during World War II, partly to avoid having to pay license fees for DDT. It was documented by Allied military intelligence, but remained in obscurity after the war. In 2019, New York University chemists reported that and a mono-fluorinated derivative, MFDT, might be a more effective insecticide than DDT, and might therefore be used to combat malaria with less of an environmental impact. | https://en.wikipedia.org/wiki?curid=62097245 |
Low-FODMAP diet A low-FODMAP diet consists in the global restriction of all fermentable carbohydrates (FODMAPs), that is recommended only for a short time. A low-FODMAP diet is recommended for managing patients with irritable bowel syndrome (IBS) and can reduce digestive symptoms of IBS including bloating and flatulence. A low-FODMAP diet might help to improve short-term digestive symptoms in adults with irritable bowel syndrome, but its long-term use can have negative effects because it causes a detrimental impact on the gut microbiota and metabolome. It should only be used for short periods of time and under the advice of a specialist. More studies are needed to evaluate its effectiveness in children with irritable bowel syndrome. There is only a little evidence of its effectiveness in treating functional symptoms in inflammatory bowel disease from small studies that are susceptible to bias. More studies are needed to assess the true impact of this diet on health. In addition, the use of a low-FODMAP diet without medical advice can lead to serious health risks, including nutritional deficiencies and misdiagnosis, so it is advisable to conduct a complete medical evaluation before starting a low-FODMAP diet to ensure a correct diagnosis and that the appropriate therapy may be undertaken | https://en.wikipedia.org/wiki?curid=62100056 |
Low-FODMAP diet Since the consumption of gluten is suppressed or reduced with a low-FODMAP diet, the improvement of the digestive symptoms with this diet may not be related to the withdrawal of the FODMAPs, but of gluten, indicating the presence of an unrecognized celiac disease, avoiding its diagnosis and correct treatment, with the consequent risk of several serious health complications, including various types of cancer. A low-FODMAP diet is highly restrictive in various groups of nutrients, can be impractical to follow in the long-term and may add an unnecessary financial burden. Below are low-FODMAP foods categorized by group according to the Monash University "Low-FODMAP Diet". Other sources confirm the suitability of these and suggest some additional foods. The basis of many functional gastrointestinal disorders (FGIDs) is distension of the intestinal lumen. Such luminal distension may induce pain, a sensation of bloating, abdominal distension and motility disorders. Therapeutic approaches seek to reduce factors that lead to distension, particularly of the distal small and proximal large intestine. Food substances that can induce distension are those that are poorly absorbed in the proximal small intestine, osmotically active, and fermented by intestinal bacteria with hydrogen (as opposed to methane) production. The small molecule FODMAPs exhibit these characteristics | https://en.wikipedia.org/wiki?curid=62100056 |
Low-FODMAP diet Over many years, there have been multiple observations that ingestion of certain short-chain carbohydrates, including lactose, fructose and sorbitol, fructans and galactooligosaccharides, can induce gastrointestinal discomfort similar to that of people with irritable bowel syndrome. These studies also showed that dietary restriction of short-chain carbohydrates was associated with symptoms improvement. These short-chain carbohydrates (lactose, fructose and sorbitol, fructans and GOS) behave similarly in the intestine. Firstly, being small molecules and either poorly absorbed or not absorbed at all, they drag water into the intestine via osmosis. Secondly, these molecules are readily fermented by colonic bacteria, so upon malabsorption in the small intestine they enter the large intestine where they generate gases (hydrogen, carbon dioxide and methane). The dual actions of these carbohydrates cause an expansion in volume of intestinal contents, which stretches the intestinal wall and stimulates nerves in the gut. It is this 'stretching' that triggers the sensations of pain and discomfort that are commonly experienced by IBS sufferers. The FODMAP concept was first published in 2005 as part of a hypothesis paper. In this paper, it was proposed that a collective reduction in the dietary intake of all indigestible or slowly absorbed, short-chain carbohydrates would minimise stretching of the intestinal wall | https://en.wikipedia.org/wiki?curid=62100056 |
Low-FODMAP diet This was proposed to reduce stimulation of the gut's nervous system and provide the best chance of reducing symptom generation in people with IBS (see below). At the time, there was no collective term for indigestible or slowly absorbed, short-chain carbohydrates, so the term 'FODMAP' was created to improve understanding and facilitate communication of the concept. The low FODMAP diet was originally developed by a research team at Monash University in Melbourne, Australia. The Monash team undertook the first research to investigate whether a low FODMAP diet improved symptom control in patients with IBS and established the mechanism by which the diet exerted its effect. Monash University also established a rigorous food analysis program to measure the FODMAP content of a wide selection of Australian and international foods. The FODMAP composition data generated by Monash University updated previous data that was based on limited literature, with guesses (sometimes wrong) made where there was little information. | https://en.wikipedia.org/wiki?curid=62100056 |
Norcholestane Norcholestane, also known by the molecular formula CH, may refer to:may refer to: | https://en.wikipedia.org/wiki?curid=62102310 |
International Federation of Petroleum and Chemical Workers The (IFPCW) was a global union federation bringing together trade union representing workers in the chemical and oil industries. The secretariat was established in 1954 at a meeting in Paris, held on the initiative of the International Confederation of Free Trade Unions (ICFTU) and the Oil Workers' International Union of the United States. It was formed in response to the growth of employment in the oil industry, and was initially named the International Federation of Petroleum Workers. Most of its founder members had previously been affiliated to the International Federation of Industrial Organisations and General Workers' Unions (IFF). The secretariat was based in Denver, and was the only global union federation to have headquarters outside Europe. By 1960, it had 43 affiliates, with a membership of more than 500,000. In 1963, the union began recruiting unions of chemical workers, and renamed itself as the "International Federation of Petroleum and Chemical Workers". This brought it into conflict with the IFF, which renamed itself as the "International Federation of Chemical and General Workers' Unions" (ICF), and the ICFTU suspended grants to both organisations. By the late 1960s, it became known that the IFPCW was receiving regular grants from CIA funds, and it became regarded as a CIA front organisation. Faced with a loss of prestige, it discussed a potential merger with the ICF, but this did not occur, and it dissolved in 1976. In 1960, the following unions were affiliated to the federation: | https://en.wikipedia.org/wiki?curid=62120907 |
Prime editing is a ‘search-and-replace’ genome editing technology in molecular biology by which the genome of living organisms may be modified. The technology directly writes new genetic information into a targeted DNA site. It uses a fusion protein, consisting of a catalytically impaired Cas9 endonuclease fused to an engineered reverse transcriptase enzyme, and a prime editing guide RNA (pegRNA), capable of identifying the target site and provide the new genetic information to replace the target DNA nucleotides. It mediates targeted insertions, deletions, and base-to-base conversions without the need for double strand breaks (DSBs) or donor DNA templates. The technology is an early-stage, experimental genome editing method that has received mainstream press attention due to its potential uses in medical genetics. It utilizes similar methodologies to precursor genome editing technologies, including CRISPR/Cas9 and base editors. As of 2019, it remains a scientific proof of concept, with no therapeutic applications. involves three major components: Genomic editing takes place by transfecting cells with the pegRNA and the fusion protein. Transfection is often accomplished by introducing vectors into a cell. Once internalized, the fusion protein nicks the target DNA sequence, exposing a 3’-hydroxyl group that can be used to initiate (prime) the reverse transcription of the RT template portion of the pegRNA | https://en.wikipedia.org/wiki?curid=62129266 |
Prime editing This results in a branched intermediate that contains two DNA flaps: a 3’ flap that contains the newly synthesized (edited) sequence, and a 5’ flap that contains the dispensable, unedited DNA sequence. The 5’ flap is then cleaved by structure-specific endonucleases or 5’ exonucleases. This process allows 3’ flap ligation, and creates a heteroduplex DNA composed of one edited strand and one unedited strand. The reannealed double stranded DNA contains nucleotide mismatches at the location where editing took place. In order to correct the mismatches, the cells exploit the intrinsic mismatch repair mechanism, with two possible outcomes: (i) the information in the edited strand is copied into the complementary strand, permanently installing the edit; (ii) the original nucleotides are re-incorporated into the edited strand, excluding the edit. During the development of this technology, several modifications were done to the components, in order to increase its effectiveness. In the first system, a wild-type Moloney Murine Leukemia Virus (M-MLV) reverse transcriptase was fused to the Cas9 H840A nickase C-terminus. Detectable editing efficiencies were observed. In order to enhance DNA-RNA affinity, enzyme processivity, and thermostability, five amino acid substitutions were incorporated into the M-MLV reverse transcriptase. The mutant M-MLV RT was then incorporated into PE1 to give rise to (Cas9 (H840A)-M-MLV RT(D200N/L603W/T330P/T306K/W313F)). Efficiency improvement was observed over PE1 | https://en.wikipedia.org/wiki?curid=62129266 |
Prime editing Despite its increased efficacy, the edit inserted by PE2 might still be removed due to DNA mismatch repair of the edited strand. To avoid this problem during DNA heteroduplex resolution, an additional single guide RNA (sgRNA) is introduced. This sgRNA is designed to match the edited sequence introduced by the pegRNA, but not the original allele. It directs the Cas9 nickase portion of the fusion protein to nick the unedited strand at a nearby site, opposite to the original nick. Nicking the non-edited strand causes the cell’s natural repair system to copy the information in the edited strand to the complementary strand, permanently installing the edit. Although additional research is required to improve the efficiency of prime editing, the technology offers promising scientific improvements over other gene editing tools. The prime editing technology has the potential to correct the vast majority of pathogenic alleles that cause genetic diseases, as it can repair insertions, deletions, and nucleotide substitutions. The prime editing tool offers advantages over traditional gene editing technologies. CRISPR/Cas9 edits rely on non-homologous end joining (NHEJ) or homology-directed repair (HDR) to fix DNA breaks, while the prime editing system employs DNA mismatch repair. This is an important feature of this technology given that DNA repair mechanisms such as NHEJ and HDR, generate unwanted, random insertions or deletions (INDELs) byproducts which complicate the retrieval of cells carrying the correct edit | https://en.wikipedia.org/wiki?curid=62129266 |
Prime editing The prime system introduces single-stranded DNA breaks instead of the double-stranded DNA breaks observed in other editing tools, such as base editors. Collectively, base editing and prime editing offer complementary strengths and weaknesses for making targeted transition mutations. Base editors offer higher editing efficiency and fewer INDEL byproducts if the desired edit is a transition point mutation and a PAM sequence exists roughly 15 bases from the target site. However, because the prime editing technology does require a precisely positioned PAM sequence to target a nucleotide sequence, it offers more flexibility and editing precision. Remarkably, prime editors allow all types of substitutions, transitions and transversions to be inserted into the target sequence. Because the prime system involves three separate DNA binding events (between (i) the guide sequence and the target DNA, (ii) the primer binding site and the target DNA, and (iii) the 3’ end of the nicked DNA strand and the pegRNA), it has been suggested to have fewer undesirable off-target effects than CRISPR/Cas9. There is considerable interest in applying gene editing methods to the treatment of diseases with a genetic component. However, there are multiple challenges associated with this approach. An effective treatment would require editing of a large number of target cells, which in turn would require an effective method of delivery and a great level of tissue specificity | https://en.wikipedia.org/wiki?curid=62129266 |
Prime editing As of 2019, prime editing looks promising for relatively small genetic alterations, but more research needs to be conducted to evaluate whether the technology is efficient in making larger alterations, such as targeted insertions and deletions. Larger genetic alterations would require a longer RT template, which could hinder the efficient delivery of pegRNA to target cells. Furthermore, a pegRNA containing a long RT template could become vulnerable to damage caused by cellular enzymes. Overall, much research will be needed before prime editing could be used to correct pathogenic alleles in human diseases. Base editors used for prime editing require delivery of both a protein and RNA molecule into living cells. Introducing exogenous gene editing technologies into living organisms is a significant challenge. One potential way to introduce a base editor into animals and plants would be to package the base editor into a viral capsid. The target organism can then be transduced by the virus to synthesize the base editor "in vivo". Common laboratory vectors of transduction such as lentivirus cause immune responses in humans, so proposed human therapies often centered around adeno-associated virus (AAV) because AAV infections are largely asymptomatic. Unfortunately, the effective packaging capacity of AAV vectors is small, approximately 4.4kb not including inverted terminal repeats. As a comparison, an SpCas9-reverse transcriptase fusion protein is 6 | https://en.wikipedia.org/wiki?curid=62129266 |
Prime editing 3kb, which doesn't even account for the lengthened guide RNA necessary for targeting and priming the site of interest. Images created with Biorender. | https://en.wikipedia.org/wiki?curid=62129266 |
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