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HandWiki is the world's largest wiki-style encyclopedia dedicated to science, technology and computing. It allows you to create and edit articles as long as you have external citations and login account. In addition, this is a content management environment that can be used for collaborative editing of original scholarly content, such as books, manuals, monographs and tutorials.

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Erectile Dysfunction
Erectile dysfunction (ED), also called impotence, is the type of sexual dysfunction in which the penis fails to become or stay erect during sexual activity. It is the most common sexual problem in men. Through its connection to self-image and to problems in sexual relationships, erectile dysfunction can cause psychological harm. In about 80% of cases, physical causes can be identified. These include cardiovascular disease; diabetes mellitus; neurological problems, such as those following prostatectomy; hypogonadism; and drug side effects. About 10% of cases are psychological impotence, caused by thoughts or feelings; here, there is a strong response to placebo treatment. The term erectile dysfunction is not used for other disorders of erection, such as priapism. Treatment involves addressing the underlying causes, lifestyle modifications, and addressing psychosocial problems. In many cases, treatment is attempted by drugs, specifically PDE5 inhibitors (such as sildenafil), which dilate blood vessels, allowing more blood to flow through the spongy tissue of the penis (akin to opening a valve further in order to allow more water to enter a fire hose). Other treatments, less commonly used, include prostaglandin pellets, inserted in the urethra; smooth-muscle relaxants and vasodilators, injected into the penis; penile implants; penis pumps; and vascular reconstructive surgery.
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  • 29 Nov 2022
Topic Review
Swisscom
Swisscom AG is a major telecommunications provider in Switzerland. Its headquarters are located at Worblaufen near Bern. The Switzerland owns 51.0 percent of Swisscom AG. According to its own published data, Swisscom holds a market share of 60% for mobile, 67% for broadband and 33% for TV telecommunication in Switzerland. Its Italian subsidiary Fastweb is attributed 16% of private clients and 29% of corporate clients share of Italian broadband and is also active in the mobile market. The Swiss telegraph network was first set up in 1852, followed by telephones in 1877. The two networks were combined with the postal service in 1920 to form the PTT (Postal Telegraph and Telephone). It struggled to develop a homegrown digital network, with the first digital exchange launched in 1986, but pioneered the NATEL A mobile service in 1978 and the GSM-based NATEL D offering a digital service in 1993. The Swiss telecommunications market was deregulated in 1997. Telecom PTT was spun off and rebranded Swisscom ahead of a partial privatisation in 1997 which has left the Swiss government with a 51% stake. Besides pioneering the first mobile telephone network NATEL A, the present-day Swisscom owns the protected brand NATEL, which is used and known only in Switzerland . 25% of Swisscom Mobile was sold to Vodafone in 2001. Since then, Swisscom has bought a majority stake in Italy's second-biggest telecom company Fastweb and invested in areas such as hospitality support, cloud services, mobile solutions and billing.
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  • 29 Nov 2022
Topic Review
Acidobacteria
Acidobacteria is a phylum of bacteria. Its members are physiologically diverse and ubiquitous, especially in soils, but are under-represented in culture.
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  • 29 Nov 2022
Topic Review
HP NewWave
NewWave is a discontinued object-oriented graphical desktop environment and office productivity tool for PCs running early versions of Microsoft Windows (beginning with 2.0). It was developed by Hewlett-Packard and introduced commercially in 1988. It was used on the HP Vectras and other IBM compatible PCs running MS Windows. From a user perspective NewWave ran on top of MS Windows and completely replaced the standard Windows Desktop and Program Manager user interface with its own object-oriented desktop interface. HP promoted NewWave until the release of Windows 95, at which time further development of the product ceased due to incompatibility with the new operating system. The NewWave GUI (together with the contemporaneous NeXTSTEP GUI) introduced the shaded "3-D look and feel" that was later widely adopted. HP encouraged independent software vendors to produce versions of applications which took advantage of NewWave functionality, allowing their data to be handled as objects instead of files. One early example was Samna Corporation (later acquired by Lotus) who produced an edition of their Microsoft Windows word processor Ami Pro entitled ‘’Ami Pro for NewWave’’. On June 20, 1988 Microsoft Corporation and Hewlett-Packard issued a press release announcing the inclusion of NewWave support in an up-coming release Microsoft Excel. NewWave featured icons, scheduled scripts in the form of "agents", and "hot connects." HP incorporated NewWave into their multi-platform office automation offerings running under their proprietary MPE and HP-UX (UNIX) minicomputer operating systems. They developed NewWave versions of key email, database, document management, personal productivity, communications and network management tools and branded all related solutions under the “HP NewWave Office” banner. Prior to the integration of HP NewWave this solution set had been known as “Business System Plus”. The “NewWave Office” term had been used previously to describe the main NewWave user desktop.
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Topic Review
Unbibium
Unbibium /uːnˈbɪbiəm/, also known as eka-thorium or simply element 122, is the currently hypothetical chemical element in the periodic table with the placeholder symbol of Ubb and atomic number 122. Unbibium and Ubb are the temporary systematic IUPAC name and symbol respectively, until a permanent name is decided upon. In the periodic table of the elements, it is expected to follow unbiunium as the second element of the superactinides, or the g-block and the fourth element of the 8th period. It has attracted recent attention, for similarly to unbiunium, it is expected to fall within the range of the island of stability. Despite many attempts, unbibium has not yet been synthesized, and therefore no natural isotopes have been found to exist. It is currently predicted that it has a g-orbital, the second element of which to have such besides unbiunium, which also has yet to be synthesized. It will most likely require nuclear fission to be produced artificially. In 2008, it was claimed to have been discovered in natural thorium samples but that claim has now been dismissed by recent repetitions of the experiment using more accurate techniques.
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Topic Review
Criticisms of Neoclassical Economics
Neo-classical economics has come under critique on the basis of its core ideologies, assumptions, and other matters.
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  • 29 Nov 2022
Topic Review
Temperature Record of the Past 1000 Years
The temperature record of the past 1,000 years or longer is reconstructed using data from climate proxy records in conjunction with the modern instrumental temperature record which only covers the last 170 years at a global scale. Large-scale reconstructions covering part or all of the 1st millennium and 2nd millennium have shown that recent temperatures are exceptional: the Intergovernmental Panel on Climate Change Fourth Assessment Report of 2007 concluded that "Average Northern Hemisphere temperatures during the second half of the 20th century were very likely higher than during any other 50-year period in the last 500 years and likely the highest in at least the past 1,300 years." The curve shown in graphs of these reconstructions is widely known as the hockey stick graph because of the sharp increase in temperatures during the last century. As of 2010 this broad pattern was supported by more than two dozen reconstructions, using various statistical methods and combinations of proxy records, with variations in how flat the pre-20th-century "shaft" appears. Sparseness of proxy records results in considerable uncertainty for earlier periods. Individual proxy records, such as tree ring widths and densities used in dendroclimatology, are calibrated against the instrumental record for the period of overlap. Networks of such records are used to reconstruct past temperatures for regions: tree ring proxies have been used to reconstruct Northern Hemisphere extratropical temperatures (within the tropics trees do not form rings) but are confined to land areas and are scarce in the Southern Hemisphere which is largely ocean. Wider coverage is provided by multiproxy reconstructions, incorporating proxies such as lake sediments, ice cores and corals which are found in different regions, and using statistical methods to relate these sparser proxies to the greater numbers of tree ring records. The "Composite Plus Scaling" (CPS) method is widely used for large-scale multiproxy reconstructions of hemispheric or global average temperatures; this is complemented by Climate Field Reconstruction (CFR) methods which show how climate patterns have developed over large spatial areas, making the reconstruction useful for investigating natural variability and long-term oscillations as well as for comparisons with patterns produced by climate models. During the 1,900 years before the 20th century, it is likely that the next warmest period was from 950 to 1100, with peaks at different times in different regions. This has been called the Medieval Warm Period, and some evidence suggests widespread cooler conditions during a period around the 17th century known as the Little Ice Age. In the hockey stick controversy, contrarians have asserted that the Medieval Warm Period was warmer than at present, and have disputed the data and methods of climate reconstructions.
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Topic Review
Supercomputer Operating Systems
Since the end of the 20th century, supercomputer operating systems have undergone major transformations, as fundamental changes have occurred in supercomputer architecture. While early operating systems were custom tailored to each supercomputer to gain speed, the trend has been moving away from in-house operating systems and toward some form of Linux, with it running all the supercomputers on the TOP500 list in November 2017. Given that modern massively parallel supercomputers typically separate computations from other services by using multiple types of nodes, they usually run different operating systems on different nodes, e.g., using a small and efficient lightweight kernel such as Compute Node Kernel (CNK) or Compute Node Linux (CNL) on compute nodes, but a larger system such as a Linux-derivative on server and input/output (I/O) nodes. While in a traditional multi-user computer system job scheduling is in effect a tasking problem for processing and peripheral resources, in a massively parallel system, the job management system needs to manage the allocation of both computational and communication resources, as well as gracefully dealing with inevitable hardware failures when tens of thousands of processors are present. Although most modern supercomputers use the Linux operating system, each manufacturer has made its own specific changes to the Linux-derivative they use, and no industry standard exists, partly because the differences in hardware architectures require changes to optimize the operating system to each hardware design.
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Biography
Walter Herrmann
Walter Herrmann (20 September 1910[1] – 11 August 1987)[2] was a Germany nuclear physicist and mechanical engineer who worked on the German nuclear energy project during World War II. After the war, he headed a laboratory for special issues of nuclear disintegration at Laboratory V in the Soviet Union. Herrmann was born in Querfurt and completed his engineering degree at the Dresden Univers
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  • 29 Nov 2022
Topic Review
Industrial Applications of Nanotechnology
Nanotechnology is impacting the field of consumer goods, several products that incorporate nanomaterials are already in a variety of items; many of which people do not even realize contain nanoparticles, products with novel functions ranging from easy-to-clean to scratch-resistant. Examples of that car bumpers are made lighter, clothing is more stain repellant, sunscreen is more radiation resistant, synthetic bones are stronger, cell phone screens are lighter weight, glass packaging for drinks leads to a longer shelf-life, and balls for various sports are made more durable. Using nanotech, in the mid-term modern textiles will become "smart", through embedded "wearable electronics", such novel products have also a promising potential especially in the field of cosmetics, and has numerous potential applications in heavy industry. Nanotechnology is predicted to be a main driver of technology and business in this century and holds the promise of higher performance materials, intelligent systems and new production methods with significant impact for all aspects of society.
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