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Topic Review
Senescent Cells
Cellular senescence, a state of permanent cell cycle arrest in response to endogenous and exogenous stimuli, triggers a series of gradual alterations in structure, metabolism, and function, as well as inflammatory gene expression that nurtures a low-grade proinflammatory milieu in human tissue. A growing body of evidence indicates an accumulation of senescent neurons and blood vessels in response to stress and aging in the retina. Prolonged accumulation of senescent cells and long-term activation of stress signaling responses may lead to multiple chronic diseases, tissue dysfunction, and age-related pathologies by exposing neighboring cells to the heightened pathological senescence-associated secretory phenotype (SASP).
  • 2.3K
  • 09 Oct 2023
Topic Review
Applications of BioHPP in Prosthetic Dentistry
BioHPP is not only extremely interesting for the future, but possesses characteristics suitable for clinical application today, for endocrowns, small adhesive bridges, temporary prostheses and for immediate loads on implant restorations. The excellent aesthetics and the possibility of simple reprocessing of the restorations made with this material invite its clinical application. 
  • 2.3K
  • 28 Mar 2022
Topic Review
Agricultural Applications of Superabsorbent Polymer Hydrogels
Although natural polymers, such as various polysaccharides, have undoubted advantages related to their biocompatibility, biodegradability, and low cost, they are inferior to synthetic polymers in terms of water absorption and water retention properties. In this regard, the most promising are semi-synthetic polymeric superabsorbents based on natural polymers modified with additives or grafted chains of synthetic polymers, which can combine the advantages of natural and synthetic polymeric hydrogels without their disadvantages. Such semi-synthetic polymers are of great interest for agricultural applications, especially in dry regions, also because they can be used to create systems for the slow release of nutrients into the soil, which are necessary to increase crop yields using environmentally friendly technologies.
  • 2.3K
  • 02 Mar 2023
Topic Review
DIetary Magnesium: Human-Animal Nutrition
Magnesium (Mg) is a mineral acting as cofactor of more than 300 enzymes. Mg in farm animals’ is recommended to avoid Mg deficiency, ensure adequate growth and health maintenance. Further, Mg supplementation above the estimated minimum requirements is the best practice to improve farm animals’ performances (fertility and yield) and food products’ quality. In human nutrition, sub-optimal Mg intake has several implications in bone development, muscle function and health maintenance.
  • 2.3K
  • 25 Feb 2021
Topic Review
Vegetation Dynamics and Climate Change
Climate extremes and their impacts on vegetation dynamics have been of great concern to the ecosystem and environmental conservation and the policy-decision makers. Of great concern now is that climate change impacts on vegetation dynamics have influenced the global terrestrial ecosystem adversely, thus making ecosystems vulnerability one of the current issues in ecological studies. For instance, the negative consequences attributed to natural hazards associated with climate extremes have been estimated to be billions of dollars across the globe. Accordingly, vegetation dynamics are influenced by several factors including climate change, environmental and climatic components among others. These can expend considerable impact on the water balance by evapotranspiration, interception and development strategy which has the potential to lead to vegetation degradation in a wide variety of ecosystems and biodiversity.
  • 2.3K
  • 30 Sep 2021
Topic Review
Sustainable Consumption of Food
The 2030 Agenda for Sustainable Development provides a global blueprint for dignity, peace, and prosperity for people and the planet, now and in the future. At its heart are the 17 Sustainable Development Goals (SDGs) as an urgent call to action by all countries—developed and developing—in a global partnership. The fact that food is the basic resource for life highlights the need for a comprehensive goal that can be achieved by reducing food waste, promoting healthy and balanced nutrition, raising awareness of the society on responsible food consumption and developing policies on food consumption by regulatory authorities in connection with ensuring the sustainability of food consumption. Therefore, ensuring sustainable food consumption can also be seen as a generic goal that can be supported by almost all SDGs. 
  • 2.3K
  • 20 Jul 2021
Topic Review
Polymeric Membranes for CO2 Capture
CO2 capture from coal- or natural gas-derived flue gas has been widely considered as the next opportunity for the large-scale deployment of gas separation membranes.  Despite the tremendous progress made in the synthesis of polymeric membranes with high CO2/N2 separation performance, only a few membrane technologies were advanced to the bench-scale study or above from a highly idealized laboratory setting.  Therefore, recent progress in polymeric membranes is reviewed in the perspectives of capture system energetics, process synthesis, membrane scale-up, modular fabrication, and field tests.  These engineering considerations can provide a holistic approach to better guide membrane research and accelerate the commercialization of gas separation membranes for post-combustion carbon capture.
  • 2.3K
  • 08 Dec 2020
Topic Review
Two-Dimensional Materials in Photodetector
A photodetector converts optical signals to detectable electrical signals. Lately, self-powered photodetectors have been widely studied because of their advantages in device miniaturization and low power consumption, which make them preferable in various applications, especially those related to green technology and flexible electronics. Since self-powered photodetectors do not have an external power supply at zero bias, it is important to ensure that the built-in potential in the device produces a sufficiently thick depletion region that efficiently sweeps the carriers across the junction, resulting in detectable electrical signals even at very low-optical power signals. Therefore, two-dimensional (2D) materials are explored as an alternative to silicon-based active regions in the photodetector. In addition, plasmonic effects coupled with self-powered photodetectors will further enhance light absorption and scattering, which contribute to the improvement of the device’s photocurrent generation.
  • 2.3K
  • 06 May 2021
Topic Review
HS-SPME-GC–MS Volatile Profile Characterization of Peach
The volatile compounds of eight peach varieties (Prunus persica L.)—“Filina”, “Gergana”, “Ufo-4”, “July lady”, “Laskava”, “Flat Queen”, “Evmolpiya”, and “Morsiani 90”—growing in Bulgaria were analyzed for the first time. Gas chromatography–mass spectrometry (GC–MS) analysis and the HS-SPME technique revealed the presence of 65 volatile compounds; the main identified components were aldehydes, esters, and fatty acids. According to the provided principal component analysis (PCA) and hierarchical cluster analysis (HCA), the relative quantities of the identified volatile compounds depended on the studied peach variety. The results obtained could be successfully applied for the metabolic chemotaxonomy of peaches.
  • 2.3K
  • 10 Feb 2022
Topic Review
Milk Thistle (Silybum marianum L.)
Milk thistle (Silybum marianum(L.) Gaertn.) is a multipurpose crop suitable to Mediterranean environments.
  • 2.3K
  • 07 Apr 2022
Topic Review
Dominance (Ethology)
Dominance in ethology is an "individual's preferential access to resources over another". Dominance in the context of biology and anthropology is the state of having high social status relative to one or more other individuals, who react submissively to dominant individuals. This enables the dominant individual to obtain access to resources such as food or potential mates at the expense of the submissive individual, without active aggression. The absence or reduction of aggression means unnecessary energy expenditure and the risk of injury are reduced for both. Dominance may be a purely dyadic relationship, i.e. individual A is dominant over individual B, but this has no implications for whether either of these is dominant over a third individual C. Alternatively, dominance may be hierarchical, with a transitive relationship, so that if A dominates B and B dominates C, A always dominates C. This is called a linear dominance hierarchy. Some animal societies have despots, i.e. a single dominant individual with little or no hierarchical structure amongst the rest of the group. Horses use coalitions so that affiliated pairs in a herd have an accumulative dominance to displace a third horse that normally out-ranks both of them on an individual basis. The opposite of dominance is submissiveness.
  • 2.3K
  • 31 Oct 2022
Topic Review
Differential Geometry of Curves
Differential geometry of curves is the branch of geometry that deals with smooth curves in the plane and in the Euclidean space by methods of differential and integral calculus. Starting in antiquity, many specific curves have been thoroughly investigated using the synthetic approach. Differential geometry takes another path: curves are represented in a parametrized form, and their geometric properties and various quantities associated with them, such as the curvature and the arc length, are expressed via derivatives and integrals using vector calculus. One of the most important tools used to analyze a curve is the Frenet frame, a moving frame that provides a coordinate system at each point of the curve that is "best adapted" to the curve near that point. The theory of curves is much simpler and narrower in scope than the theory of surfaces and its higher-dimensional generalizations, because a regular curve in a Euclidean space has no intrinsic geometry. Any regular curve may be parametrized by the arc length (the natural parametrization) and from the point of view of a theoretical point particle on the curve that does not know anything about the ambient space, all curves would appear the same. Different space curves are only distinguished by the way in which they bend and twist. Quantitatively, this is measured by the differential-geometric invariants called the curvature and the torsion of a curve. The fundamental theorem of curves asserts that the knowledge of these invariants completely determines the curve.
  • 2.3K
  • 17 Nov 2022
Topic Review
Mouse Models of Atopic Dermatitis
The complexity of atopic dermatitis (AD) continues to present a challenge in the appropriate selection of a mouse model because no single murine model completely recapitulates all aspects of human AD. This has been further complicated by recent evidence of the distinct AD endotypes that are dictated by unique patterns of inflammation involving Th1, Th2, Th17, and Th22 axes. A review of currently used mouse models demonstrates that while all AD mouse models consistently exhibit Th2 inflammation, only some demonstrate concomitant Th17 and/or Th22 induction. As the current understanding of the pathogenic contributions of these unique endotypes and their potential therapeutic roles expands, ongoing efforts to maximize a given mouse model’s homology with human AD necessitates a close evaluation of its distinct immunological signature. 
  • 2.3K
  • 23 Feb 2021
Topic Review
Biochar Production Technologies and Applications
Biochar is a carbon-rich amorphous and aromatic material that may present various interesting properties such as high hydrophobicity, alkaline nature, relevant concentrations of nutrients (N, P, and K), good water and nutrient retention capacities, low thermal conductivity, high energy content, and high superficial porosity that enable interaction with external organic and inorganic compounds. These properties are largely dependent on feedstock type and biochar production conditions. Although biochar is mostly recognized as a valuable resource for soil fertilization and conditioning, this material also has significant potential to be used for water filtration and remediation processes, as an animal feed supplement, for greenhouse gas (GHG) emission control (carbon sink feature), for insulation materials for the building sector, as an electrode material (for energy production and storage), cosmetic products, biogas production and improvement, and in catalytic processes.
  • 2.3K
  • 29 Aug 2022
Topic Review
Perspiration
Perspiration, also known as sweating, is the production of fluids secreted by the sweat glands in the skin of mammals. Two types of sweat glands can be found in humans: eccrine glands and apocrine glands. The eccrine sweat glands are distributed over much of the body and are responsible for secreting the watery, brackish sweat most often triggered by excessive body temperature. The apocrine sweat glands are restricted to the armpits and a few other areas of the body and produce an odorless, oily, opaque secretion which then gains its characteristic odor from bacterial decomposition. In humans, sweating is primarily a means of thermoregulation, which is achieved by the water-rich secretion of the eccrine glands. Maximum sweat rates of an adult can be up to 2–4 liters per hour or 10–14 liters per day (10–15 g/min·m2), but is less in children prior to puberty. Evaporation of sweat from the skin surface has a cooling effect due to evaporative cooling. Hence, in hot weather, or when the individual's muscles heat up due to exertion, more sweat is produced. Animals with few sweat glands, such as dogs, accomplish similar temperature regulation results by panting, which evaporates water from the moist lining of the oral cavity and pharynx. Although sweating is found in a wide variety of mammals, relatively few (exceptions include humans and horses) produce large amounts of sweat in order to cool down.
  • 2.3K
  • 22 Nov 2022
Topic Review
Thermochemical Heat Storage Based on CaO/CaCO3 Cycles
Thermochemical heat storage (TCHS) based on CaO/CaCO3 cycles has broad application prospects due to many advantages, such as high heat storage density, high exothermic temperature, low energy loss, low material price, and good coupling with CSP plants.
  • 2.3K
  • 04 Nov 2021
Topic Review
ShKAS Machine Gun
The ShKAS (Shpitalny-Komaritski Aviatsionny Skorostrelny, Shpitalny-Komaritski rapid fire for aircraft; Russian: ШКАС - Шпитального-Комарицкого Авиационный Скорострельный) is a 7.62 mm calibre machine gun widely used by Soviet aircraft in the 1930s and during World War II. The ShKAS had the highest rate of fire of any aircraft machine gun in general service during WWII. It was designed by Boris Shpitalniy and Irinarkh Komaritsky and entered production in 1934. ShKAS was used in the majority of Soviet fighters and bombers and served as the basis for the ShVAK cannon.
  • 2.3K
  • 24 Nov 2022
Topic Review
Hacker Culture
The hacker culture is a subculture of individuals who enjoy - often in collective effort - the intellectual challenge of creatively overcoming the limitations of software systems or electronic hardware (mostly digital electronics), to achieve novel and clever outcomes. The act of engaging in activities (such as programming or other media) in a spirit of playfulness and exploration is termed hacking. However, the defining characteristic of a hacker is not the activities performed themselves (e.g. programming), but how it is done and whether it is exciting and meaningful. Activities of playful cleverness can be said to have "hack value" and therefore the term "hacks" came about, with early examples including pranks at MIT done by students to demonstrate their technical aptitude and cleverness. The hacker culture originally emerged in academia in the 1960s around the Massachusetts Institute of Technology (MIT)'s Tech Model Railroad Club (TMRC) and MIT Artificial Intelligence Laboratory. Hacking originally involved entering restricted areas in a clever way without causing any major damage. Some famous hacks at the Massachusetts Institute of Technology were placing of a campus police cruiser on the roof of the Great Dome and converting the Great Dome into R2-D2. Richard Stallman explains about hackers who program: What they had in common was mainly love of excellence and programming. They wanted to make their programs that they used be as good as they could. They also wanted to make them do neat things. They wanted to be able to do something in a more exciting way than anyone believed possible and show "Look how wonderful this is. I bet you didn't believe this could be done." Hackers from this subculture tend to emphatically differentiate themselves from what they pejoratively call "crackers"; those who are generally referred to by media and members of the general public using the term "hacker", and whose primary focus‍—‌be it to malign or for malevolent purposes‍—‌lies in exploiting weaknesses in computer security.
  • 2.3K
  • 20 Oct 2022
Topic Review
Emotional Labor and Burnout among Teachers
A significant amount of emotional labor and burnout takes place during teaching. Teaching is a multitasking profession that consists of both cognitive and emotional components, with teachers engaging in emotional labor on a daily basis as an instrumental part of achieving teaching goals and positive learning outcomes. 
  • 2.3K
  • 28 Dec 2021
Topic Review
Planet Load-Sharing
An analysis of the scientific literature devoted to the problem of load sharing and phasing in planetary gearboxes will be presented. The wide range of research topics demonstrates the technical challenges of understanding planetary load-sharing and planet phasing. Studies included are having the goal of developing models for load sharing and exploring the positive or negative effects of different parameters such as phasing on the load distribution among planets. Practical aspects are also considered, for example, the effects of some errors that are unavoidable during manufacturing or working conditions, e.g., misalignments or position errors. Methods for improving the load-sharing characteristics, e.g., flexible ring or floating components, are discussed as well.
  • 2.3K
  • 21 Sep 2022
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