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Topic Review
Mass Spectrometry in Determination of Pesticide Residues
The extensive use of pesticides represents a risk to human health. Consequently, legal frameworks have been established to ensure food safety, including control programs for pesticide residues. In this context, the performance of analytical methods acquires special relevance. Such methods are expected to be able to determine the largest number of compounds at trace concentration levels in complex food matrices, which represents a great analytical challenge. Technical advances in mass spectrometry (MS) have led to the development of more efficient analytical methods for the determination of pesticides. 
  • 2.6K
  • 15 Jun 2022
Topic Review
Monocular 3D Object Detection Methods
Owing to recent advancements in deep learning methods and relevant databases, it is becoming increasingly easier to recognize 3D objects using only RGB images from single viewpoints. 
  • 2.6K
  • 07 Apr 2021
Topic Review
Additive Manufacturing of Soft Materials
The growing demand for wearable devices, soft robotics, and tissue engineering in recent years has led to an increased effort in the field of soft materials. With the advent of personalized devices, the one-shape-fits-all manufacturing methods may soon no longer be the standard for the rapidly increasing market of soft devices. Recent findings have pushed technology and materials in the area of additive manufacturing (AM) as an alternative fabrication method for soft functional devices, taking geometrical designs and functionality to greater heights.
  • 2.6K
  • 02 Sep 2021
Topic Review
Opioid Epidemic
The opioid epidemic or opioids crisis is the rapid increase in the use of prescription and non-prescription opioid drugs in the United States and Canada beginning in the late 1990s and continuing throughout the next two decades. The increase in opioid overdose deaths has been dramatic, and opioids are now responsible for 49,000 of the 72,000 drug overdose deaths overall in the US in 2017. A recent report indicated that the rate of prolong opioid use is increasing globally. Opioids are a diverse class of moderately strong painkillers, including oxycodone (commonly sold under the trade names OxyContin and Percocet), hydrocodone (Vicodin, Norco), and a very strong painkiller, fentanyl, which is synthesized to resemble other opiates such as opium-derived morphine and heroin. The potency and availability of these substances, despite their high risk of addiction and overdose, have made them popular both as medical treatments and as recreational drugs. Due to their sedative effects on the part of the brain which regulates breathing, the respiratory center of the medulla oblongata, opioids in high doses present the potential for respiratory depression, and may cause respiratory failure and death. In a 2015 report, the U.S. Drug Enforcement Administration stated that "overdose deaths, particularly from prescription drugs and heroin, have reached epidemic levels.":iii Nearly half of all opioid overdose deaths in 2016 involved prescription opioids. From 1999 to 2008, overdose death rates, sales, and substance abuse treatment admissions related to opioid pain relievers all increased substantially. By 2015, there were more than 50,000 annual deaths from drug overdose, causing more deaths than either car accidents or guns. Drug overdoses have since become the leading cause of death of Americans under 50, with two-thirds of those deaths from opioids. In 2016, the crisis decreased overall life expectancy of Americans for the second consecutive year. Overall life expectancy fell from 78.7 to 78.6 years. Men were disproportionately more affected due to higher overdose death rates, with life expectancy declining from 76.3 to 76.1 years. Women's life expectancy remained stable at 81.1 years. In 2016, over 64,000 Americans died from overdoses, 21 percent more than the almost 53,000 in 2015. By comparison, the figure was 16,000 in 2010, and 4,000 in 1999. While death rates varied by state, public health experts estimate that nationwide over 500,000 people could die from the epidemic over the next 10 years. In Canada , half of the overdoses were accidental, while a third were intentional. The remainder were unknown. Many of the deaths are from an extremely potent opioid, fentanyl, which is trafficked from Mexico. The epidemic cost the United States an estimated $504 billion in 2015. CDC former director Thomas Frieden said that "America is awash in opioids; urgent action is critical." The crisis has changed moral, social, and cultural resistance to street drug alternatives such as heroin. Many state governors have declared a "state of emergency" to combat the opioid epidemic or undertook other major efforts against it. In July 2017, opioid addiction was cited as the "FDA's biggest crisis". In October 2017, President Donald Trump concurred with his Commission's report and declared the country's opioid crisis a "public health emergency". Federal and state interventions are working on employing health information technology in order to expand the impact of existing drug monitoring programs. Recent research shows promising results in mortality and morbidity reductions when a state integrates drug monitoring programs with health information technologies and shares data through centralized platform.
  • 2.6K
  • 29 Sep 2022
Topic Review
Carbon Nanotube Metal Matrix Composites
Carbon nanotube metal matrix composites (CNT-MMC) are an emerging class of new materials that are being developed to take advantage of the high tensile strength and electrical conductivity of carbon nanotube materials. Critical to the realization of CNT-MMC possessing optimal properties in these areas are the development of synthetic techniques that are (a) economically producible, (b) provide for a homogeneous dispersion of nanotubes in the metallic matrix, and (c) lead to strong interfacial adhesion between the metallic matrix and the carbon nanotubes. Since the development of CNT-MMC is still in the research phase, the current focus is primarily on improving these latter two areas.
  • 2.6K
  • 29 Sep 2022
Topic Review
Art History
Art history is the study of objects of art in their historical development and stylistic contexts; that is genre, design, format, and style. The study includes painting, sculpture, architecture, ceramics, furniture, and other decorative objects. As a term, art history (its product being history of art) encompasses several methods of studying the visual arts; in common usage referring to works of art and architecture. Aspects of the discipline overlap. As the art historian Ernst Gombrich once observed, "the field of art history [is] much like Caesar's Gaul, divided in three parts inhabited by three different, though not necessarily hostile tribes: (i) the connoisseurs, (ii) the critics, and (iii) the academic art historians". As a discipline, art history is distinguished from art criticism, which is concerned with establishing a relative artistic value upon individual works with respect to others of comparable style, or sanctioning an entire style or movement; and art theory or "philosophy of art", which is concerned with the fundamental nature of art. One branch of this area of study is aesthetics, which includes investigating the enigma of the sublime and determining the essence of beauty. Technically, art history is not these things, because the art historian uses historical method to answer the questions: How did the artist come to create the work?, Who were the patrons?, Who were his or her teachers?, Who was the audience?, Who were his or her disciples?, What historical forces shaped the artist's oeuvre, and how did he or she and the creation, in turn, affect the course of artistic, political, and social events? It is, however, questionable whether many questions of this kind can be answered satisfactorily without also considering basic questions about the nature of art. The current disciplinary gap between art history and the philosophy of art (aesthetics) often hinders this inquiry. Art history is not only a biographical endeavor. Art historians often root their studies in the scrutiny of individual objects. They thus attempt to answer in historically specific ways, questions such as: What are key features of this style?, What meaning did this object convey?, How does it function visually?, Did the artist meet their goals well?, What symbols are involved?, and Does it function discursively? The historical backbone of the discipline is a celebratory chronology of beautiful creations commissioned by public or religious bodies or wealthy individuals in western Europe. Such a "canon" remains prominent, as indicated by the selection of objects present in art history textbooks. Nonetheless, since the 20th century there has been an effort to re-define the discipline to be more inclusive of non-Western art, art made by women, and vernacular creativity.
  • 2.6K
  • 02 Oct 2022
Topic Review
Fiddler Crab
A fiddler crab, sometimes known as a calling crab, may be any of approximately 100 species of semi-terrestrial marine crabs which make up the genus Uca. As members of the family Ocypodidae, fiddler crabs are most closely related to the ghost crabs of the genus Ocypode. This entire group is composed of small crabs – the largest being slightly over two inches (5 cm) across. Fiddler crabs are found along sea beaches and brackish inter-tidal mud flats, lagoons and swamps. Fiddler crabs are most well known for their sexually dimorphic claws; the males’ major claw is much larger than the minor claw while the females’ claws are both the same size. Like all crabs, fiddler crabs shed their shells as they grow. If they have lost legs or claws during their present growth cycle, a new one will be present when they molt. If the large fiddle claw is lost, males will develop one on the opposite side after their next molt. Newly molted crabs are very vulnerable because of their soft shells. They are reclusive and hide until the new shell hardens. Fiddler crabs exhibit a constant circadian rhythm in a controlled laboratory setting that mimics the ebb and flow of the tides. The crabs turn dark in the day and light in the dark.
  • 2.6K
  • 24 Nov 2022
Topic Review
High Pressure Macromolecular Crystallography
Since its introduction in the early 1970s, high pressure crystallography (HPX) has shown great potential for the investigation of different types of matter. Using diamond anvil cells, HPX is an emerging technique that has been rapidly implemented, making it available to biologists, and there is immense potential for utilizing this technique in biological systems in the future. At the molecular level, high-pressure crystallographic investigation provides information on structural characteristics that not only determine the native conformation of a protein but also the conformations with higher free-energy, thus revealing function-related structural changes and properties that can be modified as a result of pressurization. The increase in the number of crystal structures of different macromolecules determined under high pressure over the last five decades can be ascribed mainly to two factors: the emergence of high-pressure cells with very large, open angles, and the advent of third generation synchrotron sources. The use of high pressure crystallography as a research tool has been shown to contribute to the advancements in the basic fields of biochemistry (protein misfolding and aggregation), biophysics (protein stability), and biotechnology (food processing).
  • 2.6K
  • 04 Apr 2023
Topic Review
Carina
Carina, Latin for "the keel" or "the hull," is a constellation in the southern celestial hemisphere. Representing the keel of the mythical ship Argo Navis, Carina is home to several notable celestial objects, including the second-brightest star in the night sky, Canopus. It is rich in nebulae, star clusters, and other deep-sky wonders.
  • 2.6K
  • 29 Feb 2024
Topic Review
Therapeutic Approach of Flavonoid
Flavonoids are one of the most diverse families of bioactive phytochemicals, with over 9000 different compounds. According to IUPAC Recommendations (2017), the term “flavonoid” refers to compounds that have the basic structure of phenyl-substituted propylbenzene derivatives with C15 skeleton, C16 skeleton, and flavonolignans with C6–C3 lignan precursors. Flavonoids are divided into six subclasses; isoflavones, flavones, flavanols, flavonols, flavanones, and anthocyanins, are abundant in plants and their metabolic routes have been thoroughly explored using biochemical and molecular approaches.
  • 2.6K
  • 10 Nov 2021
Biography
Ursula Burns
Ursula M. Burns (born September 20, 1958), is an American businesswoman. She is the chairman of VEON,[1] a senior advisor to Teneo,[2] and a non-executive director of the beverage company Diageo since April 2018, among other directorships[3] such as Uber.[4][5] In 2009, Burns became CEO of Xerox, the first black woman CEO to head a Fortune 500 company,[6] and the first woman to succeed another a
  • 2.6K
  • 30 Nov 2022
Topic Review
Degradation and Life Prediction of Polyethylene
Polyethylene is one of the most significant and useful polymers that has been extensively studied for use as a plastic material. The benefits of using polyethylene as a commercial plastic material include its excellent mechanical properties, good flexibility, good chemical resistance, lightweight properties, good thermal stability, and high-cost performance. The piping sector has been impacted by the trend of replacing steel with plastic during the past, resulting in the steady replacement of metal-based pipes with plastic pipes. Polyethylene pipes are the most commonly utilized among them. Consider the case of high-density polyethylene pipes. Its market worth was USD 15.975 billion in 2018, and 9.283 million tons were consumed each year. The service life of polyethylene pipes will not be less than 50 years, and it will continue to grow at a rate of at least 5% annually in the upcoming years.
  • 2.6K
  • 10 Mar 2023
Topic Review
X 2000
X 2000, also called SJ X2 or simply as X2, is a tilting train operated by SJ in Sweden. It was constructed by Kalmar Verkstad in Kalmar, Sweden (prior to the company being bought by Adtranz in 1996) and launched in 1990 as a first-class only train with a meal included in the ticket price, and free use of the train's fax machine. There is a bistro on board that serves snack bar-style dishes. From 1995 second class was introduced. All trains are equipped with Wi-Fi for passenger access to the Internet and were repainted grey as of 2005. The trains also have electric power supply sockets at all seats in both first and second class. The trains have been fitted with repeaters to improve mobile phone reception. It has a top commercial speed of 200 km/h (120 mph), but has reached 276 km/h (171 mph) in a test. The reason the X2 was chosen was that Sweden (like most other countries) has very curved railways, and not enough traffic to justify building special high-speed railway lines (at least before 1990). As a result, a Swedish tilting train had to be developed. A tilting train provided the advantages of high speed and comfort for the passengers, as tilting trains can run through sharp (short radius or tight) curves up to 15% faster than non-tilting trains. The X2 was designed and built by ASEA (later ABB Asea Brown Boveri, Adtranz ABB Daimler Benz Transportation and now Bombardier Transportation). SJ ordered 20 trainsets in August 1986 and planned to order further 30 trainsets. However, this figure was later reduced to only 43 trainsets.
  • 2.6K
  • 29 Sep 2022
Topic Review
Copper Biological Active Complexes
Very few biological active Cu(II) complexes entered in clinical trials as result of poor water solubility and lipophilicity, low stability as well as in vivo inactivation. Their pharmacological and/or oral administration profile can be improved either by physically encapsulation or by conjugation to an organic matrix via a moiety able to coordinate Cu(II). As result, a large variety of species were developed as delivery carriers such as liposomes, synthetic or natural polymers or dendrimers.
  • 2.6K
  • 28 Dec 2020
Topic Review
Climate Change Concerns of Saudi Arabian Farmers
Climate change is a serious threat to the sustainability of global agriculture and food supply that necessitates taking appropriate action for building resilient food production systems and preserving rural economies. In this regard, farmers’ beliefs and concerns about the effects of climate change on agriculture may influence their adoption of adaptation and mitigation practices to address this emerging issue. 
  • 2.6K
  • 29 Nov 2021
Topic Review
Comparison of Mail Servers
This is a comparison of mail servers: mail transfer agents, mail delivery agents, and other computer software that provide e-mail services. Unix based mail servers are built using a number of components because a Unix style environment is, by default, a toolbox operating system. A stock Unix-like server already has internal mail, more traditional ones also come with a full MTA already part of the standard installation. To allow the server to send external emails, an MTA such as Sendmail, Postfix, or Exim is required. Mail is read either through direct access (shell login) or mailbox protocols like POP and IMAP. Unix based MTA software largely acts as enhancement or replacement of the respective system's "native" MTA. Windows servers do not natively implement email. Windows based MTAs therefore have to cover the whole set of email related functionality.
  • 2.6K
  • 11 Nov 2022
Topic Review
Fluorescence Polarization-Based Bioassays
Fluorescence polarization holds considerable promise for bioanalytical systems because it allows the detection of selective interactions in real time and a choice of fluorophores, the detection of which the biosample matrix does not influence; thus, their choice simplifies and accelerates the preparation of samples. For decades, these possibilities were successfully applied in fluorescence polarization immunoassays based on differences in the polarization of fluorophore emissions excited by plane-polarized light, whether in a free state or as part of an immune complex. However, the results of recent studies demonstrate the efficacy of fluorescence polarization as a detected signal in many bioanalytical methods.
  • 2.6K
  • 17 Dec 2020
Topic Review
Southern African Lion
The Southern African lion is a Panthera leo melanochaita population in Southern Africa. During the 20th century, lion populations in this part of Africa became fragmented and declined in several range countries due to loss of habitat and prey base, poaching and killing of lions to protect livestock and human life. In 2005, a Lion Conservation Strategy was developed for Southern and East Africa. Today, lion populations are stable only in large protected area complexes. In intensively managed protected areas in Botswana, Namibia, South Africa and Zimbabwe, they increased since the turn of this century. The scientific name P. l. melanochaita was proposed for the Cape lion in 1842 that was eradicated in the mid-19th century. P. l. melanochaita differs genetically from P. leo leo; the two subspecies probably diverged at least 50,000 years ago.
  • 2.6K
  • 18 Oct 2022
Topic Review
Population Ecology
Population ecology is a sub-field of ecology that deals with the dynamics of species populations and how these populations interact with the environment, such as birth and death rates, and by immigration and emigration. The discipline is important in conservation biology, especially in the development of population viability analysis which makes it possible to predict the long-term probability of a species persisting in a given patch of habitat. Although population ecology is a subfield of biology, it provides interesting problems for mathematicians and statisticians who work in population dynamics.
  • 2.6K
  • 19 Oct 2022
Topic Review
Manufacturing Methods of Phase Change Materials Microcapsules
Thermal energy storage (TES) has been identified by many researchers as one of the cost-effective solutions for not only storing excess or/wasted energy, but also improving systems’ reliability and thermal efficiency. Among TES, phase change materials (PCMs) are gaining more attention due to their ability to store a reasonably large quantity of heat within small temperature differences. Encapsulation is the cornerstone in expanding the applicability of the PCMs. Microencapsulation is a proven, viable method for containment and retention of PCMs in tiny shells. Currently, there are numerous methods available for synthesis of mPCMs, each of which has its own advantages and limitations.
  • 2.6K
  • 22 Jul 2022
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