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Topic Review
Cold Spray Additive Manufacturing
Cold Spray Additive Manufacturing (CSAM) produces freeform parts by accelerating powder particles at a supersonic speed which, impacting against a substrate material, trigger a process to consolidate the CSAM part by bonding mechanisms. Cold Spray (CS) is a thermal spray process designed for coatings that has extended its use to produce freeform parts. The definition of Additive Manufacturing (AM) given by ISO/ASTM 52900:2015 standard is the “process of joining materials to make parts from 3D model data, usually layer upon layer, as opposed to subtractive manufacturing and formative manufacturing methodologies”.
  • 1.9K
  • 17 Feb 2023
Topic Review
Mitigating Shuttle Effect in Lithium–Sulfur Batteries by Separators
Lithium–sulfur (Li-S) batteries are considered one of the most promising energy storage systems due to their high theoretical capacity, high theoretical capacity density, and low cost. However, challenges such as poor conductivity of sulfur (S) elements in active materials, the “shuttle effect” caused by lithium polysulfide, and the growth of lithium dendrites impede the commercial development of Li-S batteries. As a crucial component of the battery, the separator plays a vital role in mitigating the shuttle effect caused by polysulfide. Traditional polypropylene, polyethylene, and polyimide separators are constrained by their inherent limitations, rendering them unsuitable for direct application in lithium–sulfur batteries. Therefore, there is an urgent need for the development of novel separators. 
  • 1.9K
  • 19 Dec 2023
Topic Review
Terahertz Technology
The unique features of terahertz radiation in the context of industrial applications are highlighted. The most common terahertz systems and the way they have been applied in the industry are described. The main barriers from wide spread industry adoption and the outlook of terahertz technology are also discussed.
  • 1.9K
  • 01 Nov 2020
Topic Review
Bisphenol A-Induced Male Infertility
Bisphenol A (BPA) is a well-known endocrine disruptor present in epoxy resins and polycarbonate plastics, which negatively disturbs the male reproductive system affecting male fertility. In vivo studies showed that BPA exposure has deleterious effects on spermatogenesis by disturbing the hypothalamic-pituitary-gonadal axis and inducing oxidative stress in the testis. This compound seems to disrupt hormone signalling even at low concentrations, modifying the levels of inhibin B, oestradiol, and testosterone. The adverse effects on seminal parameters are mainly supported by studies based on urinary BPA concentration, showing a negative association between BPA levels and sperm concentration, motility, normal morphology and sperm DNA damage.
  • 1.9K
  • 01 Apr 2021
Topic Review
Plant Sterols
Plant sterols are inherent compounds of many nutritional supplements and food additives. Sterols are chemical compounds based on 1,2-cyclopentaneperhydrophenantrene and are characterized by hydroxyl moiety at the 3C position and the side chain at the 17C position. The latter makes them structurally similar to pregnenolone, which is a fundamental molecule for all 17-ketosteroids generation. The major natural source of dietary plant sterols are vegetables, fruits, berries, and vegetable oil.
  • 1.9K
  • 24 May 2021
Topic Review
Corpus luteum
The corpus luteum is a temporary endocrine gland in the ovary. In the ovarian cycle, repeated patterns of specific cellular proliferation, differentiation, and transformation occur that accompany the formation and regression of the corpus luteum. Molecular mechanism events in the ovarian microenvironment, such as angiogenesis and apoptosis, are complex. Recently, we focused on the role of RAS protein in the ovarian corpus luteum. RAS protein plays a vital role in the modulation of cell survival, proliferation, and differentiation by molecular pathway signaling. Additionally, reproductive hormones regulate RAS activity in the cellular physiological function of ovarian follicles during pre-ovulatory maturation and ovulation. Thus, we have reviewed the role of RAS protein related to the biological events of the corpus luteum in the ovary.
  • 1.9K
  • 11 Jun 2021
Topic Review
Functional Materials for Wearable Sensors
With the recent development of flexible electronic materials, smart transducers, and wireless systems, wearable sensor technology has gained significant interest in the realization of personalized medical care. The design and development of flexible/stretchable dry electrodes with good adherence to biological tissues is in great demand due to the complex attributes of the human body. However, the major difficulty is finding the appropriate materials with good flexibility and conductivity, although some other relevant features such as bio-compatibility, durability, weight, size, etc.
  • 1.9K
  • 05 Sep 2022
Topic Review
Hypoestrogenism
Hypoestrogenism, or estrogen deficiency, refers to a lower than normal level of estrogen. It is an umbrella term used to describe estrogen deficiency in various conditions. Estrogen deficiency is also associated with an increased risk of cardiovascular disease, and has been linked to diseases like urinary tract infections and osteoporosis. In women, low levels of estrogen may cause symptoms such as hot flashes, sleeping disturbances, decreased bone health, and changes in the genitourinary system. Hypoestrogenism is most commonly found in women who are postmenopausal, have primary ovarian insufficiency (POI), or are presenting with amenorrhea (absence of menstrual periods). Hypoestrogenism includes primarily genitourinary effects, including thinning of the vaginal tissue layers and an increase in vaginal pH. With normal levels of estrogen, the environment of the vagina is protected against inflammation, infections, and sexually transmitted infections. Hypoestrogenism can also occur in men, for instance due to hypogonadism. There are both hormonal and non-hormonal treatments to prevent the negative effects of low estrogen levels and improve quality of life.
  • 1.9K
  • 09 Nov 2022
Topic Review
Epidemiology of Japanese Encephalitis
Japanese encephalitis virus (JEV) is the causal agent behind Japanese encephalitis (JE), a potentially severe brain infection that spreads through mosquito bites. JE is predominant over the Asia-Pacific Region and has the potential to spread globally with a higher rate of morbidity and mortality. Efforts have been made to identify and select various target molecules essential in JEV’s progression.
  • 1.9K
  • 18 Apr 2023
Topic Review
Thermostable O6-alkylguanine-DNA Alkyltransferases
The genome of living cells is continuously exposed to endogenous and exogenous attacks, and this is particularly amplified at high temperatures. Alkylating agents cause DNA damage, leading to mutations and cell death; for this reason, a class of enzymes known as alkylguanine-DNA-alkyltransferases (AGTs) protects the DNA from mutations caused by alkylating agents, in particular in the recognition and repair of alkylated guanines in O6-position. The peculiar irreversible self-alkylation reaction of these enzymes triggered numerous studies, especially on the human homologue, in order to identify effective inhibitors in the fight against cancer. In modern biotechnology, engineered variants of AGTs are developed to be used as protein tags for the attachment of chemical ligands. In the last decade, research on AGTs from (hyper)thermophilic sources proved useful as a model system to clarify numerous phenomena, also common for mesophilic enzymes. This review traces recent progress in this class of thermozymes, emphasizing their usefulness in basic research and their consequent advantages for in vivo and in vitro biotechnological applications. 
  • 1.9K
  • 29 Oct 2020
Topic Review
Curcumin
Natural products have been used in medicine for thousands of years, in the recent times they gained a significant popularity globally due to their potential health benefits. Phytochemicals regulate differential gene expression to modulate various cellular pathways implicated in cellular protection. Curcumin is a natural dietary polyphenol extracted from Curcuma Longa L. with different biological and pharmacological effects. One of the important targets of curcumin is TLR-4, the receptor which plays a key role in the modulation of the immune responses and stimulate the production of inflammatory chemokines and cytokines. Different studies have demonstrated that curcumin attenuates inflammatory response via TLR-4 acting directly on receptor, or by its downstream pathway. Curcumin bioavailability is low, so the use of exosomes, as nano drug delivery, could improve the efficacy of curcumin in inflammatory diseases. The focus of this review is to explore the therapeutic effect of curcumin interacting with TLR-4 receptor and how this modulation could improve the prognosis of neuroinflammatory and rheumatic diseases.
  • 1.9K
  • 08 Nov 2021
Topic Review
CMOS Sensors
Depleted Complementary Metal-Oxide-Semiconductor (CMOS) sensors are emerging as one of the main candidate technologies for future tracking detectors in high luminosity colliders. Their capability of integrating the sensing diode into the CMOS wafer hosting the front-end electronics allows for reduced noise and higher signal sensitivity, due to the direct collection of the sensor signal by the readout electronics. They are suitable for high radiation environments due to the possibility of applying high depletion voltage and the availability of relatively high resistivity substrates. The use of a CMOS commercial fabrication process leads to their cost reduction and allows faster construction of large area detectors. In this contribution, a general perspective of the state of the art of CMOS detectors for High Energy Physics experiments is given. The main developments carried out with regard to these devices in the framework of the CERN RD50 collaboration are summarized.
  • 1.9K
  • 15 Dec 2020
Topic Review
Fuel Cells
Fast start-up, high efficiency, no toxic emissions into the atmosphere and good modularity are the key advantages of fuel cell applications. Despite the merits associated with fuel cells, the high cost of the technology remains a key factor impeding its widespread commercialization.
  • 1.9K
  • 13 Jan 2021
Topic Review
Food Security and Transition towards Sustainability
For decades, food security and sustainability have been considered separate concerns, with the concept of food security having a more significant connotation with sustainability dimensions such as environmental, economic, and social–cultural aspects that interpret human well-being. Food security is highly connected to food sustainability and environmental protection. Additionally, food security exists when all people at all times have physical, economic, and social access to sufficient, safe, and nutritious food. 
  • 1.9K
  • 26 Nov 2021
Topic Review
The Role of EREG/EGFR Pathway in Tumor Progression
Aberrant activation of the epidermal growth factor receptor (EGFR/ERBB1) by erythroblastic leukemia viral oncogene homolog (ERBB) ligands contributes to various tumor malignancies, including lung cancer and colorectal cancer (CRC). Epiregulin (EREG) is one of the EGFR ligands and is low expressed in most normal tissues. Elevated EREG in various cancers mainly activates EGFR signaling pathways and promotes cancer progression.
  • 1.9K
  • 13 Dec 2021
Topic Review
Bidirectional Reflection Distribution Function
The bidirectional reflection distribution function (BRDF) is among the most effective means to study the phenomenon of light–object interaction. It can precisely describe the characteristics of spatial reflection of the target surface, and has been applied to aerial remote sensing, imaging technology, materials analysis, and computer rendering technology. 
  • 1.9K
  • 15 Mar 2022
Topic Review
Iron Deficiency in Heart Failure
Iron is an essential micronutrient for a myriad of physiological processes in the body beyond erythropoiesis. Iron deficiency (ID) is a common comorbidity in patients with heart failure (HF), with a prevalence reaching up to 59% even in non-anaemic patients. ID impairs exercise capacity, reduces the quality of life, increases hospitalisation rate and mortality risk regardless of anaemia. Intravenously correcting ID has emerged as a promising treatment in HF as it has been shown to alleviate symptoms, improve quality of life and exercise capacity and reduce hospitalisations. However, the pathophysiology of ID in HF remains poorly characterised. Recognition of ID in HF triggered more research with the aim to explain how correcting ID improves HF status as well as the underlying causes of ID in the first place. In the past few years, significant progress has been made in understanding iron homeostasis by characterising the role of the iron-regulating hormone hepcidin, the effects of ID on skeletal and cardiac myocytes, kidneys and the immune system.
  • 1.9K
  • 11 Apr 2022
Topic Review
Intracellular Signalling in Wound Healing
The cells response to injury is initiated by growth factors and cytokines that play a key role in wound restoration, and their biological action is achieved via signal transduction. Growth factors and cytokines play distinct roles through all phases of wound healing. In response to injury, they can trigger several strategic signalling transduction pathways that are mostly activated during embryonic skin development. Extracellular signal-regulated kinases (ERKs) and calcium (Ca2+) are the first intracellular signalling molecules for tissue repair response. These signalling molecules regulate several biological activities including cellular migration, proliferation, contractility, survival and many more related to different transcription factors that are usually induced by several other intracellular signalling pathways. This phenomenon makes it difficult to link a specific signalling response to injury.
  • 1.9K
  • 28 Apr 2022
Topic Review
GPS Block IIIA
GPS Block IIIA consists of the first ten (known as "tranche") of GPS III satellites, which will be used to keep the Navstar Global Positioning System operational. Lockheed Martin designed, developed and manufactured the GPS III Non-Flight Satellite Testbed (GNST) and all ten Block IIIA satellites. The first satellite in the series was projected to launch in 2014, but significant delays have pushed the scheduled launch to December 2018. The tenth and final GPS Block IIIA launch is projected in Q2 2023.
  • 1.9K
  • 10 Nov 2022
Topic Review
Great Depression, U.S.
The "Great Depression" was a decade of unemployment, low profits, low prices, high poverty and stagnant trade that affected the entire world in the 1930s. Worst hit sectors were heavy industry, agriculture, mining and logging; least affected were white collar workers. The stock market crash of 1929 triggered the Great Depression in the United States which then spread to every continent. The depression ended in the late 1930s and caused major political changes, especially the New Deal that involved large scale federal relief programs, aid to agriculture, support for labor unions, and the formation of the New Deal coalition by Franklin Delano Roosevelt. The long-term memories affected the nation for decades as a consensus was reached that it would not be allowed to happen again and that the nation would have "Freedom from Fear."
  • 1.9K
  • 14 Nov 2022
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