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Topic Review
Hypoxia (Medical)
Hypoxia is a condition in which the body or a region of the body is deprived of adequate oxygen supply at the tissue level. Hypoxia may be classified as either generalized, affecting the whole body, or local, affecting a region of the body. Although hypoxia is often a pathological condition, variations in arterial oxygen concentrations can be part of the normal physiology, for example, during hypoventilation training or strenuous physical exercise. Hypoxia differs from hypoxemia and anoxemia in that hypoxia refers to a state in which oxygen supply is insufficient, whereas hypoxemia and anoxemia refer specifically to states that have low or zero arterial oxygen supply. Hypoxia in which there is complete deprivation of oxygen supply is referred to as anoxia. Generalized hypoxia occurs in healthy people when they ascend to high altitude, where it causes altitude sickness leading to potentially fatal complications: high altitude pulmonary edema (HAPE) and high altitude cerebral edema (HACE). Hypoxia also occurs in healthy individuals when breathing mixtures of gases with a low oxygen content, e.g. while diving underwater especially when using closed-circuit rebreather systems that control the amount of oxygen in the supplied air. Mild, non-damaging intermittent hypoxia is used intentionally during altitude training to develop an athletic performance adaptation at both the systemic and cellular level. In acute or silent hypoxia, a person's oxygen level in blood cells and tissue can drop without any initial warning, even though the individual's chest x-ray shows diffuse pneumonia with an oxygen level below normal. Doctors report cases of silent hypoxia with COVID-19 patients who did not experience shortness of breath or coughing until their oxygen levels had plummeted to such a degree that the patients risked acute respiratory distress (ARDS) and organ failure. In a The New York Times opinion piece (April 20, 2020), emergency room doctor Richard Levitan reports: "A vast majority of Covid pneumonia patients I met had remarkably low oxygen saturations at triage—seemingly incompatible with life—but they were using their cellphones as we put them on monitors." Hypoxia is a common complication of preterm birth in newborn infants. Because the lungs develop late in pregnancy, premature infants frequently possess underdeveloped lungs. To improve lung function, doctors frequently place infants at risk of hypoxia inside incubators (also known as humidicribs) that provide warmth, humidity, and oxygen. More serious cases are treated with CPAP. The 2019 Nobel Prize in Physiology or Medicine was awarded to William G. Kaelin Jr., Sir Peter J. Ratcliffe, and Gregg L. Semenza in recognition of their discovery of cellular mechanisms to sense and adapt to different oxygen concentrations, establishing a basis for how oxygen levels affect physiological function.
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  • 01 Dec 2022
Topic Review
Drying Biomass Using Solar Energy
In the world, energy used for drying processes consumes 7–15% of industrial energy. Therefore, the cost of this energy is a crucial challenge to looking for an alternative source of energy, for example, solar energy. Solar energy is available in almost all the world, is free and provides a clean and free pollution energy source. Furthermore, solar energy has a higher development potential than other alternative energy sources, such as the ocean, biomass and geothermal.
  • 1.5K
  • 28 Dec 2022
Topic Review
Traveling Across Life Sciences with Acetophenone
Each metabolite, regardless of its molecular simplicity or complexity, has a mission or function in the organism biosynthesizing it.  The biological, allelochemical, and chemical properties of acetophenone, as a metabolite involved in multiple interactions with various (mi-cro)organisms.
  • 1.5K
  • 28 Jan 2023
Topic Review
The Applications of Cationic Polymers
Nucleic acid therapy can achieve lasting and even curative effects through gene augmentation, gene suppression, and genome editing. However, it is difficult for naked nucleic acid molecules to enter cells. As a result, the key to nucleic acid therapy is the introduction of nucleic acid molecules into cells. Cationic polymers are non-viral nucleic acid delivery systems with positively charged groups on their molecules that concentrate nucleic acid molecules to form nanoparticles, which help nucleic acids cross barriers to express proteins in cells or inhibit target gene expression. Cationic polymers are easy to synthesize, modify, and structurally control, making them a promising class of nucleic acid delivery systems.
  • 1.5K
  • 05 Jun 2023
Topic Review
Silkworm Bombyx mori
Among insects, the silkworm Bombyx mori occupies a special position, being an excellent lepidopteran species representative of numerous scientific investigations. B. mori was domesticated and developed by human-driven selection from a wild origin since ancient times. Many years ago, silkworm genetic stocks were conserved in research facilitie. The silkworm can be considered from the economic point of view to be one of the most significant insects. It has been providing important benefits to humans, and it has continued developing thanks to its many practical applications, including using it as a model organism for medical purposes.
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  • 20 Jun 2023
Topic Review
Fruits and Beverages as Functional Foods
It is largely accepted that the daily intake of fruits, vegetables, herbal products and derivatives is an added value in promoting human health, given their capacity to counteract oxidative stress markers and suppress uncontrolled pro-inflammatory responses. Given that, natural-based products seem to be a promising strategy to attenuate, or even mitigate, the development of chronic diseases, such as diabetes, and to boost the immune system.
  • 1.5K
  • 01 Aug 2023
Topic Review
Community Resilience, Adaptive Resilience and Transformative Resilience
Resilience of human systems has increasingly gained ground as both a targeted process of societal development and as a research topic in its own right. As resilience often transcends both the natural and social sciences, it has become a basis for decision-making in studies examining the complex interactions between society, land use management, and policy. While a large body of literature exists on community resilience, there are still significant gaps in knowledge and an imminent need for further research, especially social sciences research.
  • 1.5K
  • 08 Nov 2023
Topic Review
Microbial Desalination Cell Performance Indicators and Limiting Factors
Microbial desalination cells (MDCs) are promising bioelectrochemical systems for desalination using the bacteria-generated electricity from the biodegradation of organic wastes contained in the wastewater. Instead of being a sustainable and eco-friendly desalination technology, the large-scale application of MDC was limited due to the high installation cost of the metal-catalyst-coated cathode electrode and the poor performance of the cathode in long-term operation due to catalyst fouling.
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  • 01 Nov 2022
Topic Review
Piezoelectric-Triboelectric Effects Coupled Nanogenerators
Piezoelectric and triboelectric nanogenerators have been widely studied for their advantages of easy design/manufacturing, small size, and flexibility. Nanogenerators that are developed based on the coupled piezoelectric and triboelectric effects (PTCNG) can make full use of the mechanical energies and achieve both higher output and sensing performance.
  • 1.5K
  • 08 Feb 2023
Topic Review
Physical Exercise in NAFLD
Non-alcoholic fatty liver disease (NAFLD) is a major health problem, and its prevalence has increased in recent years. Diet and exercise interventions are the first-line treatment options. The goal is to understand the complex pathophysiology underlying exercise interventions with the potential to prevent and treat NAFLD.
  • 1.5K
  • 26 Nov 2020
Topic Review
Sustainable Farming Practices in Europe
Modern practices of industrial farming, such as mineral fertilization, caused a widespread degradation of agricultural land and water bodies in Europe. Different farm management strategies exist to reduce the impact of mineral fertilization while preserving soil productivity. The specific focus is on widely adopted and empirically explored measures, such as organic farming, manure treatment technologies and manure fertilization, as well as soil and water conservation methods. Farmers' environmental and economic attitudes in addition to their sources of information have a strong effect on the adoption of organic farming, although there is a lack of evidence of their impact on adopting manure treatment and conservation measures. Similarly, farmers' age and education are found to systemically influence organic farming adoption, but not adoption of other reviewed technologies. While other factors, such as farm physical characteristics or technological attributes, may be important determinants of adoption, it is hard to recognize definite patterns of their impact across technologies given a shortage of empirical evidence.
  • 1.5K
  • 08 Dec 2020
Topic Review
Sierra Espuña Cenozoic Malaguide Basin
The Cenozoic Malaguide Basin from Sierra Espuña (Internal Betic Zone, S Spain) due to the qual-ity of outcropping, areal representation, and continuity in the sedimentation can be considered a key-basin. In the last 30 years, a large number of studies with very different methodological ap-proaches have been done in the area. Models indicate an evolution from passive margin to wedge-top basin from Late Cretaceous to Early Miocene. Sedimentation changes from limestone platforms with scarce terrigenous inputs, during the Paleocene to Early Oligocene, to the deep ba-sin with huge supplies of turbidite sandstones and conglomerates during the Late Oligocene to Early Miocene. The area now appears structured as an antiformal stack with evidence of synsedimentary tectonics.
  • 1.5K
  • 19 Jan 2021
Topic Review
6BLEMesh
6BLEMesh is a mesh topology standard over Bluetooth Low Energy (BLE). 
  • 1.5K
  • 25 May 2021
Topic Review
Applications of Nanominerals in Ruminants
A novel approach in livestock production is applying nanominerals, especially selenium (Se) and zinc (Zn), which can serve as a platform to incorporate these elements into the body. This approach enables direct transportation of active compounds to target organs, avoiding their fast degradability and encouraging several health benefits.
  • 1.5K
  • 09 Jul 2021
Topic Review
Migration, Climate Change and Livelihoods
Climate change and migration have been issues of concern among scientists for a number of decades, and various arguments have been made asserting that climate change is becoming a major driver of population displacement. It was noted in the early 1990s that “climate change greatly influenced human migration, causing displacement of millions of people who suffered erosion, agricultural disruption, and flooding”. Globally, about 25 million people were forced from their families and livelihoods during the mid-1990s, due to severe environmental crises, such as drought, flooding, pollution, and natural disasters. This type of movement can be called a “forced migration”, as it is a movement in which elements of coercion exist, such as threats to life and livelihoods. Forced migration is not only caused by environmental “push” factors, such as sea level rise, but also “pull” factors, which can also be environmental, social, and economic.
  • 1.5K
  • 17 Aug 2021
Topic Review
Ras Proteins
Ras proteins are essential mediators of a multitude of cellular processes, and its deregulation is frequently associated with cancer appearance, progression, and metastasis. Ras-driven cancers are usually aggressive and difficult to treat. Although the recent Food and Drug Administration (FDA) approval of the first Ras G12C inhibitor is an important milestone, only a small percentage of patients will benefit from it.
  • 1.5K
  • 10 Sep 2021
Topic Review
Obstructive Apnea and Hypopnea Length
Breathing is an essential function that requires both metabolic and behavioral control during wakefulness but depends on metabolic control during sleep. Breathing also depends on the maturity of the neural centers and the strength of the respiratory muscles. In patients with sleep disordered breathing, breathing after an apneic event results from the interaction between chemoreceptors relaying information to brainstem neurons responsible for generating breathing patterns and influencing respiratory motor neurons controlling the airway muscles; both of these mechanisms are also affected by sleep stage physiology.
  • 1.5K
  • 22 Oct 2021
Topic Review
Uncrewed Aerial Vehicles in Bridge Inspection
Uncrewed Aerial Vehicles (UAV) constitute a rapidly evolving technology field that is becoming more accessible and capable of supplementing, expanding, and even replacing some traditionally manual bridge inspections. Given the classification of the bridge inspection types as initial, routine, in-depth, damage, special, and fracture critical members, specific UAV mission requirements can be developed, and their suitability for UAV application examined.
  • 1.5K
  • 06 Apr 2022
Topic Review
Pyrolysis of Biosolids to Produce Biochars
Biochar is a solid, charcoal material that can be used in different applications such as its use in agriculture as a soil enhancer in which moisture content is sustained for long periods of times. Biosolids or biosludges will refer to any form of sludge that has undergone some form of treatment (e.g., chemical, biological, heat treatment, etc.) in order to transform it into a less hazardous and organic form. More importantly, there seems to be an inconsistency in defining what classifies as biosolids, hence, a unified definition is established and provided. The aim is to enable the scientific community as a whole to use a standard definition that allows for synergies to take place. Specifically, the pyrolysis process is selected and is known as a thermochemical technique in which heat and an oxygen-free environment facilitate the decomposition of the feedstock into different products, depending on the operating parameters.
  • 1.5K
  • 14 Sep 2022
Topic Review
Pseudo-reorganization Acquisitions
Pseudo-reorganization acquisitions are acquisitions that are done in order to repatriate income earned by foreign subsidiaries to a parent corporation while avoiding taxes ordinarily owed on the repatriation of foreign income in countries with a worldwide system of taxation. Prior to the passage of the Tax Cut and Jobs Act of 2017, multinational firms based in the United States avoided taxes on the repatriation of income earned abroad through the use of pseudo-reorganization acquisitions.
  • 1.5K
  • 06 Oct 2022
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