Summary

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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FAO Country Profiles
The FAO Country Profiles are a multilingual web portal which repackages the Food and Agriculture Organization of the United Nations (FAO) information archive on its global activities in agriculture and food security in a single area and catalogues it exclusively by country and thematic areas. The organization aims to offer decision-makers, researchers and project formulators around the world a fast and reliable way to access country-specific information on national food security situations without the need to search individual databases and systems. It aids FAO's database by providing a simple interface containing interactive maps and charts.
  • 3.3K
  • 09 Nov 2022
Topic Review
ZnO Nanostructures
Zinc oxide (ZnO) nanostructures are structures with at least one dimension on the nanometre scale, composed predominantly of zinc oxide. They may be combined with other composite substances to change the chemistry, structure or function of the nanostructures in order to be used in various technologies. Many different nanostructures can be synthesised from ZnO using relatively inexpensive and simple procedures. ZnO is a semiconductor material with a wide band gap energy of 3.3eV and has the potential to be widely used on the nanoscale. ZnO nanostructures have found uses in environmental, technological and biomedical purposes including ultrafast optical functions, dye-sensitised solar cells, lithium-ion batteries, biosensors, nanolasers and supercapacitors. Research is ongoing to synthesise more productive and successful nanostructures from ZnO and other composites. ZnO nanostructures is a rapidly growing research field, with over 5000 papers published during 2014-2019.
  • 1.1K
  • 07 Nov 2022
Topic Review
Simultaneously Extracted Metals and Acid-Volatile Sulfide
Simultaneously extracted metals/Acid-volatile sulfide (SEM-AVS) is an approach used in the field of aquatic toxicology to assess the potential for metal ions found in sediment to cause toxic effects in organisms dwelling in the sediment. In this approach, the amounts of several heavy metals in a sediment sample are measured in a laboratory; at the same time, the amount of acid-volatile sulfide (sulfide which can be liberated from the sediment by treatment with hydrochloric acid) is determined. Based on the chemical interactions between heavy metals (SEM) and acid-volatile sulfide (AVS), the concentrations of these two components can be used to assess the potential for toxicity to sediment-dwelling organisms.
  • 1.1K
  • 07 Nov 2022
Topic Review
Atomic Commit
In the field of computer science, an atomic commit is an operation that applies a set of distinct changes as a single operation. If the changes are applied, then the atomic commit is said to have succeeded. If there is a failure before the atomic commit can be completed, then all of the changes completed in the atomic commit are reversed. This ensures that the system is always left in a consistent state. The other key property of isolation comes from their nature as atomic operations. Isolation ensures that only one atomic commit is processed at a time. The most common uses of atomic commits are in database systems and version control systems. The problem with atomic commits is that they require coordination between multiple systems. As computer networks are unreliable services, this means no algorithm can coordinate with all systems as proven in the Two Generals Problem. As databases become more and more distributed, this coordination will increase the difficulty of making truly atomic commits.
  • 1.9K
  • 07 Nov 2022
Topic Review
Parity
In quantum mechanics, a parity transformation (also called parity inversion) is the flip in the sign of one spatial coordinate. In three dimensions, it can also refer to the simultaneous flip in the sign of all three spatial coordinates (a point reflection): It can also be thought of as a test for chirality of a physical phenomenon, in that a parity inversion transforms a phenomenon into its mirror image. All fundamental interactions of elementary particles, with the exception of the weak interaction, are symmetric under parity. The weak interaction is chiral and thus provides a means for probing chirality in physics. In interactions that are symmetric under parity, such as electromagnetism in atomic and molecular physics, parity serves as a powerful controlling principle underlying quantum transitions. A matrix representation of P (in any number of dimensions) has determinant equal to −1, and hence is distinct from a rotation, which has a determinant equal to 1. In a two-dimensional plane, a simultaneous flip of all coordinates in sign is not a parity transformation; it is the same as a 180° rotation. In quantum mechanics, wave functions that are unchanged by a parity transformation are described as even functions, while those that change sign under a parity transformation are odd functions.
  • 4.1K
  • 10 Nov 2022
Topic Review
C-Fos
In the fields of molecular biology and genetics, c-fos is a proto-oncogene that is the human homolog of the retroviral oncogene v-fos. It was first discovered in rat fibroblasts as the transforming gene of the FBJ MSV (Finkel–Biskis–Jinkins murine osteogenic sarcoma virus) (Curran and Tech, 1982). It is a part of a bigger Fos family of transcription factors which includes c-Fos, FosB, Fra-1 and Fra-2. It has been mapped to chromosome region 14q21→q31. c-Fos encodes a 62 kDa protein, which forms heterodimer with c-jun (part of Jun family of transcription factors), resulting in the formation of AP-1 (Activator Protein-1) complex which binds DNA at AP-1 specific sites at the promoter and enhancer regions of target genes and converts extracellular signals into changes of gene expression. It plays an important role in many cellular functions and has been found to be overexpressed in a variety of cancers.
  • 1.7K
  • 07 Nov 2022
Topic Review
Health Risk Assessment
A health risk assessment (also referred to as a health risk appraisal and health & well-being assessment) is a questionnaire about a person's medical history, demographic characteristics and lifestyle. It is one of the most widely used screening tools in the field of health promotion and is often the first step in multi-component health promotion programs.
  • 1.7K
  • 07 Nov 2022
Topic Review
The First Year Experience Program
The First-Year Experience (FYE) (also known as the Freshman-Year Experience or the Freshman Seminar Program) is a program at many United States colleges and universities designed to help students prepare for the transition from high school to college. FYE programs often foster the participation of students in co-curricular events such as common reads, concerts, art exhibits, and guest lectures. Depending on the school, the course can last anywhere from two weeks to a full school year. Some larger universities, such as the University at Albany, SUNY, through their Project Renaissance Program,create a "small college" feel by allowing freshmen to do their first-year courses in one section of the university. While the origins of the program remain unclear, many people attribute the start of the First-Year Seminar to the University of South Carolina, which houses the National Resource Center for the First-Year Experience and Students in Transition and holds a series of workshops for colleges and universities to better their own first-year programs.
  • 789
  • 07 Nov 2022
Topic Review
Guard Rail
Guard rail, guardrails — or railings around properties and more generally outside of North America in some uses overlaps the industrial term "guide rail". They are a boundary feature and may be a means to prevent or deter access to dangerous or off-limits areas while allowing light and visibility in a greater way than a fence. Common shapes are flat, rounded edge, and tubular in horizontal railings, whereas tetraform spear-headed or ball-finialled are most common in vertical railings around homes. Park and garden railings commonly in metalworking feature swirls, leaves, plate metal areas and/or motifs particularly on and beside gates. High security railings (particularly if in flat metal then a type of palisade) may instead feature jagged points and most metals are well-suited to anti-climb paint. A handrail is less restrictive on its own than a guard rail and provides support.
  • 1.8K
  • 07 Nov 2022
Topic Review
Devices Using Qualcomm Snapdragon Systems-on-Chip
This is a list of devices using Qualcomm Snapdragon chips. Snapdragon is a family of mobile system on a chip (SoC) made by Qualcomm for use in smartphones, tablets, and smartbook devices.
  • 5.1K
  • 07 Nov 2022
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