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Topic Review
Physical Activity Patterns
Although “physical activity pattern” (PAP) is a widely used expression, its precise meaning remains vague. Indeed, PAP is sometimes used to describe physical activity (PA) levels/intensities, however the term is also applied to express how PA averages differ among group,  between different days (i.e., week and weekend days), across seasons (e.g., summer, winter), and between school and vacation time. A lack of a formal definition for PAP has not prevented researchers from using a vast array of instruments to measure PA (accelerometers, pedometers, questionnaires, direct observations, and heart rate monitors) in an attempt to capture PAP. Discrepancies also exist in how PAP has been expressed with researchers using daily mean PA, heart rate frequency, number of daily steps, time engaged in certain types of activity, and/or engagement in sports activities. Researchers have also used numerous statistical procedures in their attempts to capture PAP. Notwithstanding this diversity, we suggest that PAP should be used to jointly capture similarities/dissimilarities as well as stabilities/changes in children’s PA at an intra-personal level. PAP should be used to best describe individual streams of behaviours, and not exclusively PA levels/intensities. A formal and clear definition of PAP would support important, systematic, and coherent lines of empirical enquiry.
  • 4.1K
  • 24 Apr 2021
Topic Review
Sting-Related Deaths in Europe (1994–2016)
Bees and wasps provide an important service to ecosystems, contributing to the improvement of biodiversity while helping to maintain ecological balance. Although not frequent, hornet, wasp, and bee stings may be life-threatening. With each sting, Hymenopterans inject a small amount of venom that can cause reactions of varying intensity: (i) normal local reactions (NLR), (ii) large local reactions (LLR), (iii) systemic anaphylactic reactions (SAR), (iv) systemic toxic reactions (STR) and (v) unusual reactions (UR).  Hymenopteran stings have recently become a worldwide public health concern. However, this health problem can be underestimated despite the number of cases presented. With the expansion of non-native Hymenopteran species across Europe, allergists should be aware that their community’s exposures are continually changing.
  • 4.1K
  • 28 Feb 2022
Topic Review
Single Cell Protein
Single cell protein (SCP) is the first product of the fermentation process and has proven to be a good protein alternative. Food competition is becoming more intense as the world’s population continues to grow. Soon, SCP may be able to compensate for a protein deficit. Various global businesses are focusing on SCP production, and the scope of its application is expanding as time and knowledge increases.
  • 4.1K
  • 30 Aug 2021
Topic Review
Burn Pathophysiology
Burns are a widespread global public health traumatic injury affecting many people worldwide. Non-fatal burn injuries are a leading cause of morbidity, resulting in prolonged hospitalization, disfigurement, and disability, often with resulting stigma and rejection. The treatment of burns is aimed at controlling pain, removing dead tissue, preventing infection, reducing scarring risk, and tissue regeneration. 
  • 4.1K
  • 26 May 2023
Topic Review
Step-Down Partial Power DC-DC Converters
Photovoltaic (PV) systems made-up by two-stages of energy conversion are attractive from the operation point view. It is because the MPPT range is extended, due to the voltage decoupling between the PV system and the dc-link. Nevertheless, the additional conversion stage increases the volume, cost and power converter losses. Therefore, in large-scale PV systems formed by series connection of PV modules, most of commercial inverters are based on a single-stage system. The concept of partial power converters (PPC), previously implemented as a step-up stage, has not fully covered all PV applications. In this work, a PPC performing step-down operation is proposed and analyzed for a PV string application. This concept is actually interesting from the industry point of view, since with the new isolation standards of PV modules reaching 1500V, larger strings are currently starting to become popular. Since grid connection remains below 690V, larger strings impose more demanding operation for single-stage central inverters (required to operate at lower modulation indexes and demand higher blocking voltage devices). 
  • 4.1K
  • 01 Nov 2020
Biography
Ben Horowitz
Benjamin Abraham Horowitz (born June 13, 1966) is an American businessman, investor, blogger, and author. He is a high technology entrepreneur and co-founder and general partner along with Marc Andreessen of the venture capital firm Andreessen Horowitz. He previously co-founded and served as president and chief executive officer of the enterprise software company Opsware, which Hewlett-Packard a
  • 4.1K
  • 21 Nov 2022
Topic Review
Purple Tomatoes
Purple tomatoes represent a recent variant of tomato fruits characterized by a purple coloration, not present in the more common red fruited varieties. This peculiar pigmentation is due to the presence of anthocyanins. These are plant secondary metabolites responsible for red, purple and blue colorations of flowers, fruits and leaves in many species. They are usually assumed with the diet, being rich sources mostly represented by red and purple fruits or dark vegetables (e.g., berries, cherries, plums, grapes, black beans, red onions, eggplant, red cabbage, purple sweet potatoes). As other polyphenolic compounds, they can provide many health benefits, and, as a consequence, their consumption can be helpful in reducing the incidence of cardiovascular, metabolic and degenerative or chronic diseases and of certain types of cancer. Tomato fruits are naturally rich of carotenoids, vitamins and polyphenols, but do not contain anthocyanins, due to mutations in their specific biosynthetic pathway. However, in recent years, either through genetic engineering or introgression by breeding of specific gene variants using wild relatives, this biosynthetic block has been overcome. This allowed the production of the new tomatoes’ phenotypes characterized by purple pigmentation localized only on the fruit peel or in both peel and flesh. In purple tomatoes, the high concentrations of anthocyanins that can be achieved, and not to the detriment of other metabolites, represent a real added nutritional value of these fruits.
  • 4.1K
  • 15 Jan 2021
Topic Review
Antibacterial Designs for Implantable Medical Devices
The uses of implantable medical devices are safer and more common since sterilization methods and techniques were established a century ago; however, device-associated infections (DAIs) are still frequent and becoming a leading complication as the number of medical device implantations keeps increasing.
  • 4.1K
  • 01 Aug 2022
Topic Review
Multi-Dimensional Concept of Sustainable Development and Urban Governance
Modern cities bear the entire burden and responsibility of operationalizing the concept of sustainable development, since they are the ones that represent the greatest threat to its implementation. The sustainability of cities largely depends on the form of public governance and decision making; in fact, this interdependence is a prerequisite for all the relevant progress in sustainable development that many European cities strive to achieve. An approach to governance in European cities that has proven to be the most effective in achieving urban sustainability is an integrated one, as it encompasses the coordination, cooperation and integration of sectoral policies and the participation of different actors at all levels of governance.
  • 4.1K
  • 16 Jun 2023
Topic Review
Cat-Scratch Disease’s Neuro-Ophthalmological Effects
Cat-scratch disease is an illness caused by Bartonella henselae that occurs as a result of contact with an infected kitten or dog, such as a bite or scratch. It is more prevalent in children and young adults, as well as immunocompromised individuals. Among the ophthalmologic disorders caused by cat-scratch disease in humans, Parinaud oculoglandular syndrome, uveitis, vitritis, retinitis, retinochoroiditis and optic neuritis are the most prevalent. The neurological disorders caused by cat-scratch disease in humans include encephalopathy, transverse myelitis, radiculitis, and cerebellar ataxia.
  • 4.1K
  • 21 Feb 2022
Topic Review
Carbohydrates, Deep and REM Sleep
Carbohydrate quantity was shown to affect sleep architecture, and especially N3 and REM sleep stages. Alterations in both quantity and quality of carbohydrate intake showed a significant effect on sleep initiation. Variations in carbohydrate quality significantly affected measures of sleep continuation. Further studies are needed to assess the effect of long-term carbohydrate interventions on sleep. 
  • 4.1K
  • 28 Sep 2021
Topic Review
Issues and Challenges of Solid-State Transformer Technology
Solid-state transformer (SST) technology is one of the developing technologies that will be widely used in the future to integrate low-voltage and high-voltage networks with control circuitries and power electronics converters, facilitating renewables integration in smart grid applications. SST technology has crucial key advantageous features, including compact size and weight, low cost, and ease of connection in offshore applications. However, SST technology exhibits a few concerns, such as implementation, protection, economic, and communication compatibility, that need to be addressed.
  • 4.1K
  • 16 Sep 2022
Biography
Anthony Fauci
Anthony Stephen Fauci OMRI (born December 24, 1940) is an American physician-scientist and immunologist serving as the Director of the National Institute of Allergy and Infectious Diseases (NIAID) and the Chief Medical Advisor to the President. As a physician with the National Institutes of Health (NIH), Fauci has served the American public health sector in various capacities for more than fift
  • 4.1K
  • 15 Nov 2022
Topic Review
Chemical Depolymerization Methods of Poly(ethylene terephthalate)
The significant amount of waste generated by poly(ethylene terephthalate) (PET) requires the development of a recycling process chain in which chemical recycling plays an important role. On the one hand, it allows the depolymerization of degraded plastics that do not meet the quality requirements to be used in mechanical recycling, and on the other hand, provides an opportunity to process cheap waste and obtain products with greater added value. It can be widely used in the recycling of both packaging plastics and textiles, or other waste generated with PET.
  • 4.1K
  • 12 Oct 2023
Topic Review
Silicon-Based Optical Phased Array Lidar
Silicon-based Lidar is an ideal way to reduce the volume of the Lidar and realize monolithic integration. It removes the moving parts in the conventional device and realizes solid-state beam steering. The advantages of low cost, small size, and high beam steering speed have attracted the attention of many researchers. 
  • 4.1K
  • 07 Jul 2023
Topic Review
Structure of the Earth
The internal structure of the Earth is layered in spherical shells: an outer silicate solid crust, a highly viscous asthenosphere and mantle, a liquid outer core that is much less viscous than the mantle, and a solid inner core. Scientific understanding of the internal structure of the Earth is based on observations of topography and bathymetry, observations of rock in outcrop, samples brought to the surface from greater depths by volcanoes or volcanic activity, analysis of the seismic waves that pass through the Earth, measurements of the gravitational and magnetic fields of the Earth, and experiments with crystalline solids at pressures and temperatures characteristic of the Earth's deep interior.
  • 4.1K
  • 26 Oct 2022
Topic Review
Economy Car
An economy car is an automobile that is designed for low-cost purchase and operation. Typical economy cars are small (compact or subcompact), lightweight, and inexpensive to buy. Economy car designers are forced by stringent design constraints to be inventive. Many innovations in automobile design were originally developed for economy cars, such as the Ford Model T and the Austin Mini. The alternative approach, other than innovating to build a low-cost car, is to build a stripped-down, no-frills version of a conventional car. Gordon Murray, the Formula 1 and McLaren F1 designer, said when designing his new Murray T.25 city car: "I would say that building a car to sell for six thousand pounds and designing that for a high-volume production, where you have all the quality issues under control, is a hundred times more difficult than designing a McLaren F1, or even a racing car. It is certainly the biggest challenge I've ever had from a design point of view."
  • 4.1K
  • 17 Oct 2022
Topic Review
Coypu
The coypu (from spa coipú, from arn koypu; Myocastor coypus), also known as the nutria, is a large, herbivorous, semiaquatic rodent. Classified for a long time as the only member of the family Myocastoridae, Myocastor is now included within Echimyidae, the family of the spiny rats. The coypu lives in burrows alongside stretches of water, and feeds on river plant stems. Originally native to subtropical and temperate South America, it has since been introduced to North America, Europe, Asia, and Africa, primarily by fur farmers. Although it is still hunted and trapped for its fur in some regions, its destructive burrowing and feeding habits often bring it into conflict with humans, and it is considered an invasive species.
  • 4.1K
  • 04 Nov 2022
Topic Review
High Performance Liquid Chromatography with Fluorescence Detection Methods
Steroids are compounds widely available in nature and synthesized for therapeutic and medical purposes. Although several analytical techniques are available for the quantification of steroids, their analysis is challenging due to their low levels and complex matrices of the samples. The efficiency and quick separation of the high performance liquid chromatography (HPLC) combined with the sensitivity, selectivity, simplicity, and cost-efficiency of fluorescence, make HPLC coupled to fluorescence detection (HPLC-FLD) an ideal tool for routine measurement and detection of steroids.
  • 4.1K
  • 01 Aug 2022
Topic Review
Homelessness
Homelessness is the circumstance when people are without a permanent dwelling, such as a house or apartment. People who are homeless are most often unable to acquire and maintain regular, safe, secure and adequate housing. The legal definition of homeless varies from country to country, or among different jurisdictions in the same country or region. The term homeless may also include people whose primary night-time residence is in a homeless shelter, a domestic violence shelter, long-term residence in a motel, a vehicle, squatting, cardboard boxes, a tent city, tarpaulins, shanty town structures made of discarded building materials or other ad hoc housing situations. According to the UK homelessness charity Crisis, a home is not just a physical space: it also provides roots, identity, security, a sense of belonging and a place of emotional wellbeing. United States government homeless enumeration studies also include people who sleep in a public or private place not designed for use as a regular sleeping accommodation for human beings. There are a number of organizations who provide help for the homeless. In 2005, an estimated 100 million (1 in 65 at the time) people worldwide were homeless and as many as 1 billion people live as squatters, refugees or in temporary shelter, all lacking adequate housing. In Western countries, the majority of homeless are men (50–80%), with single males particularly overrepresented. However, current data suggests similar rates of homeless males and females. Most countries provide a variety of services to assist homeless people. These services often provide food, shelter (beds) and clothing and may be organized and run by community organizations (often with the help of volunteers) or by government departments or agencies. These programs may be supported by the government, charities, churches and individual donors. Many cities also have street newspapers, which are publications designed to provide employment opportunity to homeless people. While some homeless have jobs, some must seek other methods to make a living. Begging or panhandling is one option, but is becoming increasingly illegal in many cities. People who are homeless may have additional conditions, such as physical or mental health issues or substance addiction; these issues make resolving homelessness a challenging policy issue. Homeless people, and homeless organizations, are sometimes accused or convicted of fraudulent behaviour. Criminals are also known to exploit homeless people, ranging from identity theft to tax and welfare scams. These incidents often lead to negative connotations on the homeless as a group.
  • 4.1K
  • 30 Oct 2022
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