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is the stunning, elaborate interior that gives the church a status of an artistic treasure hidden amongst the busy and densely-packed residential streets of Rome. The ceiling is home to a piece by High Baroque painter Giovanni Battista Gaulli (also known as Baciccio), entitled The Triumph of the Name of Jesus, shown here directly, and in the angled floor mirror |
BY DR EMILY BALDWIN Posted: 26 January, 2009 Exploiting the Very Large Telescope’s acute infrared capabilities, astronomers have uncovered intense star-forming regions and a supermassive black hole in nearby galaxy NGC 253. NGC 253 is shown here as observed with the WFI instrument, while the insert shows a close-up of |
the central parts as observed with the NACO instrument on ESO's Very Large Telescope and the ACS on the NASA/ESA Hubble Space Telescope. This unique set of observations has allowed astronomers to uncoveri many young, massive and dusty stellar nurseries as well as a twin of our own Milky Way's |
supermassive black hole. Image: ESO. Measuring 70,000 light-years across and lying 13 million light years away, NGC 253 appears nearly edge-on from the Earth, and is one of the brightest and dustiest spiral galaxies known. Astronomers from the Instituto de Astrofísica de Canarias in Spain used ESO’s Very Large Telescope |
(VLT) and its adaptive optics instrument NACO (which corrects for the blurring effect introduced by the Earth's atmosphere that causes stars to twinkle) to discern a host of new young, massive and dusty stellar nurseries previously hidden within the galaxy, some with features just 11 light-years across. High resolution radio |
maps are comparatively easy to attain since radio waves are not affected by the turbulence of the atmosphere, and since radio waves have much longer wavelengths than visible light it is possible to combine observations from well-separated radio telescopes using interferometry. But the new observations allowed the astronomers to identify |
37 distinct bright regions, a threefold increase on previous results, packed into a tiny region at the core of the galaxy, comprising just one percent of the galaxy's total size. Close-up of the central regions of the starburst galaxy NGC 253. The bright regions are probably very active nurseries that |
contain as many as one hundred thousand young, massive stars bursting from their dusty cocoons. The field of view is 15 arcseconds. Image: ESO. Furthermore, they suspect that there is a scaled-up version of Sagittarius A*, the bright radio source that lies at the core of the Milky Way and |
which we know harbours a massive black hole, lurking in the centre of NGC 253. "We have thus discovered what could be a twin of our Galaxy's centre," says Almudena Prieto. Combining the NACO images with data from VISIR, another VLT instrument, as well as with images from the Hubble |
Space Telescope and radio observations made by the Very Large Array and the Very Large Baseline Interferometer, the astronomers painted a picture of the galaxy in different wavelengths, yielding clues as to the nature of the bright regions. "We now think that these are probably very active nurseries that contain |
many stars bursting from their dusty cocoons," says Jose Antonio Acosta-Pulido. NGC 253 is known as a starburst galaxy, after its very intense star formation activity. The team report that each bright region could contain as many as one hundred thousand young, massive stars. This special publication features the photography |
of British astro-imager Nik Szymanek and covers a range of photographic methods from basic to advanced. Beautiful pictures of the night sky can be obtained with a simple camera and tripod before tackling more difficult projects, such as guided astrophotography through the telescope and CCD imaging. U.S. & WORLDWIDE STORE |
Henry Gray (18251861). Anatomy of the Human Body. 1918. capsule. They pass, in a more or less longitudinal manner, up the inferior surface of the bladder, over its vertex, and then descend along its fundus to become attached to the prostate in the male, and to the front of the vagina in the female. At the sides of the bladder the fibers are arranged |
obliquely and intersect one another. This layer has been named the Detrusor urinæ muscle. The fibers of the middle circular layer are very thinly and irregularly scattered on the body of the organ, and, although to some extent placed transversely to the long axis of the bladder, are for the most part arranged obliquely. Toward the lower part of the bladder, around the internal |
urethral orifice, they are disposed in a thick circular layer, forming the Sphincter vesicæ, which is continuous with the muscular fibers of the prostate. The internal longitudinal layer is thin, and its fasciculi have a reticular arrangement, but with a tendency to assume for the most part a longitudinal direction. Two bands of oblique fibers, originating behind the orifices of the ureters, converge to |
the back part of the prostate, and are inserted by means of a fibrous process, into the middle lobe of that organ. They are the muscles of the ureters, described by Sir C. Bell, who supposed that during the contraction of the bladder they serve to retain the oblique direction of the ureters, and so prevent the reflux of the urine into them. The |
submucous coat (tela submucosa) consists of a layer of areolar tissue, connecting together the muscular and mucous coats, and intimately united to the latter. The mucous coat (tunica mucosa) is thin, smooth, and of a pale rose color. It is continuous above through the ureters with the lining membrane of the renal tubules, and below with that of the urethra. The loose texture of |
the submucous layer allows the mucous coat to be thrown into folds or rugæ when the bladder is empty. Over the trigonum vesicæ the mucous membrane is closely attached to the muscular coat, and is not thrown into folds, but is smooth and flat. The epithelium covering it is of the transitional variety, consisting of a superficial layer of polyhedral flattened cells, each with |
one, two, or three nuclei; beneath these is a stratum of large club-shaped cells, with their narrow extremities directed downward and wedged in between smaller spindle-shaped cells, containing oval nuclei (Fig. 1141). The epithelium varies according as the bladder is distended or contracted. In the former condition the superficial cells are flattened and those of the other layers are shortened; in the latter they |
present the appearance described above. There are no true glands in the mucous membrane of the bladder, though certain mucous follicles which exist, especially near the neck of the bladder, have been regarded as such. Vessels and Nerves.The arteries supplying the bladder are the superior, middle, and inferior vesical, derived from the anterior trunk of the hypogastric. The obturator and inferior gluteal arteries also |
supply small visceral branches to the bladder, and in the female additional branches are derived from the uterine and vaginal arteries. The veins form a complicated plexus on the inferior surface, and fundus near the prostate, and end in the hypogastric veins. The lymphatics are described on page 712. The nerves of the bladder are (1) fine medullated fibers from the third and fourth |
sacral nerves, and (2) non-medullated fibers from the hypogastric plexus. They are connected with ganglia in the outer and submucous coats and are finally distributed, all as non-medullated fibers, to the muscular layer and epithelial lining of the viscus. Abnormalities.A defect of development, in which the bladder is implicated, is known under the name of extroversion of the bladder. In this condition the lower |
part of the abdominal wall and the anterior wall of the bladder are wanting, so that the fundus of the bladder presents on the abdominal surface, and is pushed forward by the pressure of the viscera within the abdomen, forming a red vascular tumor on which the openings of the ureters are visible. The penis, except the glans, is rudimentary and is cleft on |
Sometimes we need to test our interaction with a certain dependency, but doing so proves difficult. But using a certain trick, we can get nearly the same assurance we're seeking without all the hassle. Let's say you want to test |
that when you lock your bedroom door, it cannot be opened from the outside. The problem is that there's only one door, and you're all by yourself. So if you actually step outside the door, lock it, and shut it, |
you'll be locked out of your own bedroom. Getting back in may be difficult, expensive or even impossible. One approach to testing this could be to stand on the inside, lock it, and try to pull it open. But first |
of all that won't work with many types of locks, which automatically unlock themselves when turned from the inside. But more importantly, this doesn't give us the assurance that it can't be opened from the outside when locked, which is |
precisely what we want to test. This isn't that different from testing software. Sometimes we want to test an interaction with something like a database or the file system. If we tried to use the real thing in our tests, |
it would likely be problematic. Setting up the environment for tests and ensuring it's taken down correctly is tricky and often slows down tests. Plus it can easily become a bottleneck to making the test suite portable between different machines. |
The key is to make use of known principles, and test around them instead of through them. Let's look at our door example. We know that whether the handle can be turned is independent of whether the door is closed. |
So while the door is open, we can test that the outside handle can't be turned when the lock is enabled. This gives us assurance that the lock makes the handle unable to be turned from the outside. We already |
have half our assurance. The only behavior left to test is that when the door is pushed at from the outside, it doesn't open. We can test this with the door unlocked so we don't lock ourselves out, since we've |
just proven that it's impossible to turn the handle when it's locked anyway. So pushing at the door is equivalent to trying to open it properly when locked. These are the only two tests we need to give us nearly |
complete assurance that nobody can open the door from the outside when it's locked. It may not be literally the same as locking yourself out, but it's as close as we'll get without having a locksmith on call. All we |
had to do was design the right tests taking into account the relevant principles at work. Let's say we want to test that our object-under-test searches our database for any names beginning with "Bob". We don't need to load up |
a database and fire up a real query just to generate this kind of assurance. Instead we can rely on the documentation of our database which indicates that a query using the = operator may use wildcards (asterisks) in the |
string. Our first test would state that our object-under-test calls the function FindNamesBeginningWith() passing in the string "Bob". Our second test states that this function sends a SQL query to the database containing "WHERE NAME = '?*'" and the string |
argument. (In real life each database has it's own unique API for doing this, but that's beside the point.) One extra benefit of this technique is that if either behavior breaks in our production code, only one test will fail. |
For example if we call the function just right, but the function doesn't generate the right SQL query, our test that says we call the function will still pass. If we were to use the real database throughout our test |
suite, then every test whose execution path included that function would also fail, disguising the real source of the problem with an avalanche of mysteriously failing tests with potentially obfuscating output. There are a few caveats with this technique. For |
one thing, these principles are implied, so they're virtually hidden. If we were to apply this principle in some tests, either the name of the test or the comments should indicate the principle assumed to be at work in the |
test. Otherwise the tests become fragile. Communication between teammates is the key here, especially some kind of longer-term communication. Another caveat is that, unlike with physics, the laws of a given software library may not match up with another library, |
or even a future version of the selfsame library. In the above example, this test might pass with MySQL but fail if we switched to PostgreSQL. Or, it may pass with MySQL 2, but tomorrow a teammate may upgrade the |
system to MySQL 3, and although your tests would pass, the functionality would break in production. This technique isn't a panacea, and it may be the wrong solution in many circumstances. But as with all tools in our generalized tool-belts, |
it has a time and place, and you may one day find this is the best solution for the task at hand. On that day, I hope this analogy serves well as an alternative perspective when deciding what kind of |
The topic personal data in the cloud has at least two perspectives. There is the end user perspective where we as users ask ourselves whether our data in the cloud are safe. And there is the enterprise perspective. Suppose you want to start a cloud based service and store personal data of end users in the cloud. What are the issues to be taken |
care of here? In this article we take the enterprise perspective. Of course we can hardly answer the above question in full. We rather focus on some legal aspects in cases where your company resides in the EU. One of the key ideas behind cloud computing is that end users do not need to care where their data reside. Servers hosting these data may |
be located anywhere on the globe. Since cloud computing saw its strongest early development in the US it is a fact that most companies offering cloud services are US based and many data centers are located in the US. We currently see more and more date centers being opened in Asia and Europe as well. If data being stored on these servers are personal |
data, there may be an issue because there is no uniform agreement about how personal data may be used in different countries around the world. There may not even be a uniform understanding about the term personal data. And that is in fact the case. The European Union is known to have the strictest regulations about how personal data may be handled by authorities, |
administrations, and private companies. The base for this is the data protection directive of the EU. Part of this directive is the ban to export any personal data to countries or organisations that do not offer the same level of data protection as is installed in the EU by this directive. So how can we ensure that we do not violate the directive when |
storing personal data in the cloud? To answer the question we first have to understand what personal data are. The EU directive deliberately chooses to take a wide notion of the term personal data. According to the directive, Personal data are defined as “any information relating to an identified or identifiable natural person (“data subject”); an identifiable person is one who can be identified, |
directly or indirectly, in particular by reference to an identification number or to one or more factors specific to his physical, physiological, mental, economic, cultural or social identity;” (art. 2 a). Typical examples are addresses, bank account or credit card information, medical records, criminal records, company employee data and the like. The use of personal data is governed by the following three principles: transparency, |
legitimate purpose, and proportionality. Transparency basically requires that the persons whose data are used have to give their consent for doing so and know what is used, when it is used and for what purpose. Legitimate purpose means that the data collected may only be used for the purpose the persons agreed to and not for any other purposes. Proportionality requires that only those |
data are collected and processed that are needed to perform the legitimate task and that these data are kept up to date and correct. Now that we understand the notion of personal data a bit better let’s look at some solutions to the data protection problem when storing data in the cloud. No Solution: The Safe Harbor Agreement When introducing the directive, the European |
Commission understood that there has been a regular exchange of personal data between EU member states and third countries, in particular the US. Therefore the so-called Safe Harbor data privacy program was initiated. The program basically allows US companies to audit themselves to adhere to the EU data protection directive and self-certify this adherence. A couple of reviews initiated by the EU to state |
the quality of this self-certification process revealed that the quality of the certification is extremely poor. The last survey, performed in 2008, showed that out of the then up-to-date list of about 1,600 US companies claiming their compliance only as little as 3% were in fact compliant. So, we cannot rely on such a certificate. The situation for German companies that intend to store |
data in a cloud is even worse. The reason for this is that the German authorities decided to draw consequences of the review results. In particular the Düsseldorfer Kreis, the convention of Germany’s governmental data protection agencies, declared in April 2010 that data exporting companies cannot rely on Safe Harbor certificates but rather have to check with the companies receiving the data that the |
receiving companies comply to the directive. In effect this basically means that the exporting company has to perform and document the auditing of the compliance of the data receiving company. In other words it is valid to assume that the exporting company takes legal responsibility for the correct storage and use of personal data on the side of the importing company. This is plainly |
impossible to perform. How should a mid size company in Germany audit and check an internet giant like Microsoft or Google, which have legal departments that are bigger in size than the total number of employees in the German company? So we see here that - We can’t consider the Safe Harbor agreement as a solution to the original problem. - Neither does it |
seem a wise move to transfer any personal data to companies which certified themselves as such a Safe Harbor. Simple Solution: Stay at Home A number of US based cloud service providers have understood that EU based companies have problems to export personal data. In order to foster their business in the EU they decided to open data centers in the EU. Companies like |
Amazon, Google, and Microsoft nowadays offer their customers to choose the geographical location of the data center(s) where their data should reside. This is more or less the simplest solution. Some companies including Amazon, Google, and Microsoft even run more than one data centre in the EU in case one is in need of a geographically remote backup centre. Technical Solution: Depersonalise your Data |
There may yet be another solution in cases where the cloud service provider does not operate data centers in the EU. The EU directive deliberately refrained from defining an explicit catalogue of what counts as personal data and rather defined personal data as any set of data that can be used to identify an individual person. This abstract definition allows for a technical solution |
to the problem. The technical solution consists in using data encryption. The following conditions have to be fulfilled for a valid solution. - All personal data have to be encrypted. - The encryption keys have to be individual to each customer. A general solution where the cloud service provider encrypts all stored data with one and the same key for all customers does not |
provide sufficient protection. - The customer and no one else must be capable of decrypting the data. - The decryption keys have to reside within the European Union. Methods following these guidelines effectively depersonalise the data. Now, that the data are not personal any more, they are no longer subject to the EU data protection directive and may hence be stored at any data |
center around the world. Since the Safe Harbor agreement should currently be regarded as a failure, the EU data protection directive basically prohibits the export of personal data out of the EU. As a consequence care has to be taken when thinking about transferring personal data into the cloud, because the principle of data storage virtualisation, a key concept of the cloud, stands in |
direct contrast with the data export ban. Fortunately there are two solutions to this problem which allow us to adhere to the data protection directive and still use the cloud for the storage of personal data. One consists in choosing a provider that offers customers to store their data in data centers within the EU. The second consists in depersonalising the data so that |
When agriculture conquers the sky – Part 2 The rising human population leads to increased demand for optimised agriculture. “Vertical farming” is one very promising method within many new approaches. According to the ideas of scientists and planers, vertical farms grow into enormous heights. A building with 30 storeys could supply 50,000 people with vegetables, fruit, eggs, fish and chicken. |
Agricultural crops raised in such highrise greenhouses would only require one tenths of the water and five percent of the area needed for plants grown on conventional fields. The top floors would be used for hydro-cultures, whereas the bottom would house chicken farms and fish basins. Wind turbines, solar panels and even tidal power are planned to supply such mega-farm |
with energy. A vertical farm would largely be self-sufficient: Animals would eat plant waste; nitrogen and other fertilisers could be obtained from manure or sewage from the surrounding towns. But, experts warn that this is still a far cry from reality: The technological innovations for these ideas do not exist yet. A multi-story hothouse requires extensive lighting and air-conditioning, and |
the construction costs would have to be covered by the sales of food – an economic feat requiring a lot of time and support. Additionally, it has to be clear that these urban farms cannot provide all food staples. Grain, wheat, maize and rice cannot be cultivated inside because they need space for growing. Storage and transport of these cereals |
is also not very costly. Vertical farming would be especially profitable for fast growing plants like lettuce or herbs. Although this may all seem like the distant future, many inquiries into this project have been made by interested parties in China and the USA. The next projects are to be launched in Shanghai and, close to us, in the quaint |
town Linköping in Sweden. There, a greenhouse shaped like a glass cone is in planning. Hundreds, maybe even thousands, of small transport carts will transport plant pots for more than 50 meters on conveyors from the top to the bottom of this highrise building. Mostly Asian vegetables will be grown on about 4,000 square meters. The Swedes have targeted to |
The Nebraska History Museum recently acquired a milk pasteurizer used by the Wright family in Pawnee County, Nebraska. Dean and Opal Wright purchased the pasteurizer from the Sears, Roebuck, & Co. catalog in 1952. Their son, Merlin, had polio that |
year, and they believed he may have contracted it from their farm cows. This was prior to the development of the polio vaccine. Dr. Jonas Salk developed the Inactivated Polio Vaccine in 1952, and nationwide testing began in 1954. This |
advertisement from the Fall and Winter 1951-1952 Sears catalog warns costumers of the dangers and raw milk and explains how the pasteurizer works. Milk is placed in a removable bucket and placed inside the aluminum canister. After plugging it in |
A heat wave across the United States during June, July and August set more than 2,000 daily high temperature records, according to scientists at the National Oceanic and Atmospheric Administration’s |
(NOAA) National Climatic Data Center in Asheville, N.C. The record heat helped make August the second-warmest and the summer season the sixth-warmest for the contiguous United States, according to preliminary |
data. The global surface temperature during June, July and August was the seventh-warmest. Highlights released Thursday by NOAA: — The average temperature for June, July and August in the contiguous |
United States was 73.8 degrees Fahrenheit, 1.7 degrees Fahrenheit above the mean for the 20th century. — The average temperature for August in the contiguous United States was 75.4 degrees |
Fahrenheit, 2.7 degrees Fahrenheit above the mean for the 20th century. — More than 30 record highs were set during the summer season. — A record high temperature in Raleigh-Durham, |
N.C., of 105 degrees Fahrenheit was set Aug. 21. The temperature in Columbia, S.C., was at least 100 degrees Fahrenheit for 14 straight days, breaking a record of 12 straight |
days set in 1900. The temperature in Cincinnati was at least 100 degrees Fahrenheit for record-setting 5 straight days. It was the warmest August in 113 years for Alabama, Florida, |
Georgia, Kentucky, North Carolina, South Carolina, Tennessee and Utah. — The combined global land and ocean surface temperature for August was 0.85 degrees Fahrenheit above the 20th Century mean and |
the eighth-warmest. — The global surface temperature for June, July and August (northern hemisphere’s summer season) was the seventh-warmest. — Hurricane Dean, the first major hurricane of the Atlantic hurricane |
season made landfall near Costa Maya on Aug. 21 as a Category 5 storm. It was the first Atlantic Basin hurricane to make landfall as a Category 5 storm since |
Hurricane Andrew struck Florida in August 1992. Click to view “Climate of 2007 — August in Historical Perspective.” NOAA, a scientific agency of the U.S. Department of Commerce, focuses on |
the conditions of the oceans and the atmosphere. NOAA warns of dangerous weather, charts seas and skies, guides the use and protection of ocean and coastal resources, and conducts research |
year of the Bahá’í calendar and the falls on the vernal equinox. The holiday has wider cultural and national significance for modern Iranians who often celebrate with family and friends by sharing meals together, cleaning their homes, buying new clothes, and performing contemporary expressions of ancient customs. Rooted in Zoroastrianism (the prophet Zoroaster himself is credited with creating this festival) |
in pre-Islamic Persia, Nowruz is also celebrated in surrounding geographic regions influenced by the Persian empire in the countries of Iraq, Turkey, and Afghanistan. “Everyone lines up, and, one by one, each person jumps over the piles and sings, ‘zardi-ye-man az to, sorkhi-ye to az man,’ the special song means ‘my yellowness is yours, your redness is mine.’ Iranians believe, |
people give pain and negativities to the fire, and receive the warmth, the health and strength from the fire.” The traditional haft-seen table is an important part of Nowruz celebrations. Iranians prepare these settings in their homes by gathering seven items that start with the letter “s,” which have positive meanings: the spice sumac for sunrise, seeb (apples) for beauty, |
and sir (garlic) for health, among others. Goldfish also make an appearance on the haft-seen table. They are symbols of new life and the end of the astral year associated with the zodiac sign Pisces. They are sold in markets along with other Nowruz accoutrements. Sabzeh is sprouted wheat grass, symbolizing rebirth and renewal of nature. On the thirteenth day |
of the celebration, it is customary to throw these sprouts away into running water, as the sabzeh is thought to collect negativity and illness in the household while it grew there. This purging represents purification and new beginnings. |
To Hide is to Thrive Malware is just plain insidious. It can do very wicked things on a very large scale. Ostensibly, to do the dirt, malware must fly under |
the radar of the good guys’ defenses. When it comes to the art and science of detecting and concealing malware, for decades an escalating war of complexity has raged on |
betwixt the benevolent and the malevolent. This article aims to be a 98% assembly language free (mov al, 61h) examination of that arms race, with a specific focus on a |
brief history of malware obfuscation. Obfuscation of malware serves the one ultimate purpose: Survival. Early on, malware authors learned that for their dark little creations to spread and prosper, they |
must be kept hidden from the sentinels of light. The longer a piece of malware can stay undetected, the longer it has to spread and evolve. If malware didn’t take |
measures to conceal itself, it would be easy pickins for the front-line troops in the AV vendors’ armies, the pattern matchers. Additionally, as malware stays enshrouded, it eschews analysis by |
the experts, which further complicates efforts to scrutinize its internal yum-yumness (and subsequently come up with methods to detect and destroy). Viral Legerdemain is Born… The first piece of malware |
that attempted to conceal its existence was also one of the earliest worldwide infectors. The Brain virus, written by the Farooq Alvi brothers in 1986, would cover-up attempts to read |
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