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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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List of Unnumbered Minor Planets: 2001 A–R
This is a partial list of unnumbered minor planets for principal designations assigned between 1 January 2001 and 15 September 2001 (A–R).
  • 509
  • 24 Oct 2022
Topic Review
Big-Box Store
A big-box store (also supercenter, superstore, or megastore) is a physically large retail establishment, usually part of a chain of stores. The term sometimes also refers, by extension, to the company that operates the store. The store may sell general dry goods, in which case it is a department store, or may be limited to a particular specialty (such establishments are often called "category killers") or may also sell groceries, in which case some countries (mostly in Europe) use the term hypermarket. Typical architectural characteristics include the following: Commercially, big-box stores can be broken down into two categories: general merchandise (examples include Walmart, Kmart and Target), and specialty stores (such as Home Depot, Barnes & Noble, or Best Buy) which specialize in goods within a specific range, such as hardware, books, or consumer electronics respectively. In the late 20th and early 21st centuries, many traditional retailers—such as Tesco and Praktiker opened stores in the big-box-store format in an effort to compete with big-box chains, which are expanding internationally as their home markets reach maturity.
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  • 26 Oct 2022
Topic Review
Prompt (Command)
This article presents a list of commands used by DOS operating systems, especially as used on x86-based IBM PC compatibles (PCs). Other DOS operating systems are not part of the scope of this list. In DOS, many standard system commands were provided for common tasks such as listing files on a disk or moving files. Some commands were built into the command interpreter, others existed as external commands on disk. Over the several generations of DOS, commands were added for the additional functions of the operating system. In the current Microsoft Windows operating system, a text-mode command prompt window, cmd.exe, can still be used.
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  • 24 Oct 2022
Topic Review
Cynicism
Cynicism (Ancient Greek:) is a school of thought of ancient Greek philosophy as practiced by the Cynics (Ancient Greek:; Latin: Cynici). For the Cynics, the purpose of life is to live in virtue, in agreement with nature. As reasoning creatures, people can gain happiness by rigorous training and by living in a way which is natural for themselves, rejecting all conventional desires for wealth, power, and fame, and even flouting conventions openly and derisively in public. Instead, they were to lead a simple life free from all possessions. The first philosopher to outline these themes was Antisthenes, who had been a pupil of Socrates in the late 400 BC. He was followed by Diogenes, who lived in a ceramic jar on the streets of Athens. Diogenes took Cynicism to its logical extremes, and came to be seen as the archetypal Cynic philosopher. He was followed by Crates of Thebes, who gave away a large fortune so he could live a life of Cynic poverty in Athens. Cynicism gradually declined in importance after the 3rd century BC, but it experienced a revival with the rise of the Roman Empire in the 1st century. Cynics could be found begging and preaching throughout the cities of the empire, and similar ascetic and rhetorical ideas appeared in early Christianity. By the 19th century, emphasis on the negative aspects of Cynic philosophy led to the modern understanding of cynicism to mean a disposition of disbelief in the sincerity or goodness of human motives and actions.
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  • 24 Oct 2022
Topic Review
Biaxial Tensile Testing
Biaxial tensile testing is a versatile technique to address the mechanical characterization of planar materials. Typical materials tested in biaxial configuration include metal sheets, silicone elastomers, composites, thin films, textiles and biological soft tissues.
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  • 24 Oct 2022
Topic Review
Rapid Prompting Method
The rapid prompting method (RPM) is a pseudoscientific technique that attempts to aid communication by people with autism or other disabilities to communicate through pointing, typing, or writing. Also known as Spelling to Communicate. It is closely related to the scientifically discredited technique facilitated communication (FC). Practitioners of RPM refuse to allow unbiased scientific analysis of the method, saying that it would be stigmatizing and that allowing scientific criticisms of the technique robs people with autism of their right to communicate. The American Speech-Language-Hearing Association has issued a statement opposing the practice of RPM. Soma Mukhopadhyay is credited with creating RPM, though others have developed similar techniques, known as informative pointing or alphabet therapy. RPM users report unexpected literacy skills in their clients, as well as a reduction in some of the behavioral issues associated with autism. As noted by Stuart Vyse, although RPM differs from facilitated communication in some ways, "it has the same potential for unconscious prompting because the letter board is always held in the air by the assistant. As long as the method of communication involves the active participation of another person, the potential for unconscious guidance remains." Critics warn that RPM's over-reliance on prompts (verbal and physical cuing by facilitators) may inhibit development of independent communication in its target population. As of April 2017, only one scientific study attempting to support Mukhopadhyay's claims of efficacy has been conducted, though reviewers found the study had serious methodological flaws. Vyse has noted that rather than proponents of RPM subjecting the methodology to properly controlled validation research, they have responded to criticism by going on the offensive, claiming that scientific criticisms of the technique rob people with autism of their right to communicate, while the authors of a 2019 review concluded that "...until future trials have demonstrated safety and effectiveness, and perhaps more importantly, have first clarified the authorship question, we strongly discourage clinicians, educators, and parents of children with ASD from using RPM."
  • 1.4K
  • 24 Oct 2022
Topic Review
Study of Animal Locomotion
The study of animal locomotion is a branch of biology that investigates and quantifies how animals move.
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  • 24 Oct 2022
Topic Review
Scientific Workflow System
A scientific workflow system is a specialized form of a workflow management system designed specifically to compose and execute a series of computational or data manipulation steps, or workflow, in a scientific application.
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  • 24 Oct 2022
Topic Review
Aircraft Noise
Aircraft noise is noise pollution produced by aircraft during the various phases of a flight. Sound production is divided into three categories: Health consequences include sleep disturbance, hearing impairment and heart disease, as well as workplace accidents caused by stress. Memory and recall can also be affected. Governments have enacted extensive controls that apply to aircraft designers, manufacturers, and operators, resulting in improved procedures and cuts in pollution.
  • 2.6K
  • 26 Oct 2022
Topic Review
Keto–Enol Tautomerism
In organic chemistry, keto–enol tautomerism refers to a chemical equilibrium between a keto form (a ketone or an aldehyde) and an enol (an alcohol). The keto and enol forms are said to be tautomers of each other. The interconversion of the two forms involves the movement of an alpha hydrogen atom and the reorganisation of bonding electrons; hence, the isomerism qualifies as tautomerism. A compound containing a carbonyl group (C=O) is normally in rapid equilibrium with an enol tautomer, which contains a pair of doubly bonded carbon atoms adjacent to a hydroxyl (−OH) group, C=C-OH. The keto form predominates at equilibrium for most ketones. Nonetheless, the enol form is important for some reactions. The deprotonated intermediate in the interconversion of the two forms, referred to as an enolate anion, is important in carbonyl chemistry, in large part because it is a strong nucleophile. Normally, the keto–enol tautomerization chemical equilibrium is highly thermodynamically driven, and at room temperature the equilibrium heavily favors the formation of the keto form. A classic example for favoring the keto form can be seen in the equilibrium between vinyl alcohol and acetaldehyde (K = [enol]/[keto] ≈ 3 × 10−7). However, it is reported that in the case of vinyl alcohol, formation of a stabilized enol form can be accomplished by controlling the water concentration in the system and utilizing the kinetic favorability of the deuterium-produced kinetic isotope effect (kH+/kD+ = 4.75, kH2O/kD2O = 12). Deuterium stabilization can be accomplished through hydrolysis of a ketene precursor in the presence of a slight stoichiometric excess of heavy water (D2O). Studies show that the tautomerization process is significantly inhibited at ambient temperatures ( kt ≈ 10−6 M/s), and the half-life of the enol form can easily be increased to t1/2 = 42 minutes for first-order hydrolysis kinetics. Another exception is the 1,3-diketones, such as acetylacetone (2,4-pentanedione), which favor the enol form.
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