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Topic Review
ZrB2 Nanopowders Solid-State Synthesis
ZrB2 is of particular interest among ultra-high temperature ceramics because it exhibits excellent thermal resistance at high temperature, as well as chemical stability, high hardness, low cost, and good electrical and thermal conductivity, which meet the requirements of high-temperature components of hyper-sonic aircraft in extreme environments. In recent years, the development of ZrB2 powders’ synthesis method has broken through the classification of traditional solid-phase method, liquid-phase method, and gas-phase method, and there is a trend of integration of them. Solid-state synthesis, including the borothermic reduction method, carbothermic reduction method, and metallothermic reduction method, is mostly used because the process is simple and the raw materials are cheap and easily available. 
  • 1.5K
  • 26 Oct 2021
Topic Review
NLRP3 and Preeclampsia
Preeclampsia (PE) is a specific syndrome of human pregnancy, being one of the main causes of maternal death. Persistent inflammation in the endothelium stimulates the secretion of several inflammatory mediators, activating different signaling patterns. One of these mechanisms is related to NLRP3 activation, initiated by high levels of danger signals such as cholesterol, urate, and glucose, producing IL-1, IL-18, and cell death by pyroptosis. Furthermore, reactive oxygen species (ROS), act as an intermediate to activate NLRP3, contributing to subsequent inflammatory cascades and cell damage. Moreover, increased production of ROS may elevate nitric oxide (NO) catabolism and consequently decrease NO bioavailability. NO has many roles in immune responses, including the regulation of signaling cascades. At the site of inflammation, vascular endothelium is crucial in the regulation of systemic inflammation with important implications for homeostasis.
  • 1.5K
  • 19 Nov 2021
Topic Review
GRACE and GRACE-FO
The Gravity Recovery and Climate Experiment (GRACE) was a joint mission of NASA and the German Aerospace Center (DLR). Twin satellites took detailed measurements of Earth's gravity field anomalies from its launch in March 2002 to the end of its science mission in October 2017. The Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) is a continuation of the mission on near-identical hardware, launched in May 2018. By measuring gravity anomalies, GRACE showed how mass is distributed around the planet and how it varies over time. Data from the GRACE satellites is an important tool for studying Earth's ocean, geology, and climate. GRACE was a collaborative endeavor involving the Center for Space Research at the University of Texas at Austin, NASA's Jet Propulsion Laboratory, the German Aerospace Center and Germany's National Research Center for Geosciences, Potsdam. The Jet Propulsion Laboratory was responsible for the overall mission management under the NASA ESSP (Earth System Science Pathfinder) program. The principal investigator is Byron Tapley of the University of Texas Center for Space Research, and the co-principal investigator is Christoph Reigber of the GeoForschungsZentrum (GFZ) Potsdam. The two GRACE satellites (GRACE-1 and GRACE-2) were launched from Plesetsk Cosmodrome, Russia, on a Rockot (SS-19 + Breeze upper stage) launch vehicle on 17 March 2002. The spacecraft were launched to an initial altitude of approximately 500 km at a near-polar inclination of 89°. During normal operations, the satellites were separated by 220 km along their orbit track. This system was able to gather global coverage every 30 days. GRACE far exceeded its 5-year design lifespan, operating for 15 years until the decommissioning of GRACE-2 on 27 October 2017. Its successor, GRACE-FO, was successfully launched on 22 May 2018. In 2019, a glacier in West Antarctica was named after the GRACE mission.
  • 1.5K
  • 23 Nov 2022
Topic Review
Audio Mastering
Mastering, a form of audio post production, is the process of preparing and transferring recorded audio from a source containing the final mix to a data storage device (the master), the source from which all copies will be produced (via methods such as pressing, duplication or replication). In recent years digital masters have become usual, although analog masters, such as audio tapes, are still being used by the manufacturing industry, notably by a few engineers who have chosen to specialize in analog mastering. Mastering requires critical listening; however, software tools exist to facilitate the process. Results still depend upon the intent of the engineer, the accuracy of the speaker monitors, and the listening environment. Mastering engineers may also need to apply corrective equalization and dynamic compression in order to optimise sound translation on all playback systems. It is standard practice to make a copy of a master recording, known as a safety copy, in case the master is lost, damaged or stolen.
  • 1.5K
  • 28 Nov 2022
Topic Review
Liquid–Gas Jet Pump
The liquid–gas jet pump (LGJP) is a kind of fluid conveying machinery and mixing reaction equipment, utilizing high-speed working liquid ejected from the nozzle to transfer energy to pumped gas through momentum exchange.
  • 1.5K
  • 03 Feb 2023
Topic Review
Plant Food Dyes with Antioxidant Properties and Allergies
Color is an important food attribute which increases its attractiveness, thus influencing consumer preferences and acceptance of food products. The characteristic color of fresh, raw food is due to natural dyes present in natural food sources. Food loses its natural color during processing or storage. Loss of natural color (e.g., graying) often reduces the appeal of a product to consumers. To increase the aesthetic value of food, natural or synthetic dyes are added to it. Interestingly, the use of food coloring to enhance food attractiveness and appetizing appearance has been practiced since antiquity. Food coloring can also cause certain health effects, both negative and positive. Dyes added to food, both natural and synthetic, are primarily chemical substances that may not be neutral to the body. Some of these substances have strong antioxidant properties.
  • 1.5K
  • 06 Jul 2023
Topic Review
Road Anomaly Detection, Deep Learning-Based Methods and Visual-SLAM
The proliferation of autonomous vehicles (AVs) emphasises the pressing need to navigate challenging road networks riddled with anomalies like unapproved speed bumps, potholes, and other hazardous conditions, particularly in low- and middle-income countries. These anomalies not only contribute to driving stress, vehicle damage, and financial implications for users but also elevate the risk of accidents. A significant hurdle for AV deployment is the vehicle’s environmental awareness and the capacity to localise effectively without excessive dependence on pre-defined maps in dynamically evolving contexts.
  • 1.5K
  • 23 Oct 2023
Topic Review
Nematicidal Activity of Essential Oils and Root-Knot Nematodes
The Meloidogyne genus is widely recognized for its significant economic and scientific importance within the group of plant-parasitic nematodes. The chemical management of nematodes presents its challenges and heavily depends on employing soil fumigants containing toxic and costly nematicides. However, plant-derived essential oils offer promising alternatives, demonstrating a wide range of biological activities that affect nematodes through a range of mechanisms, including disrupting their nervous systems, inducing detrimental effects on plasma membrane permeability, penetrating the gelatinous matrix of nematode eggs, and disturbing intracellular redox status. Most of the extracted essential oils were predominantly sourced from the Lamiaceae family (32%), followed by Asteraceae (11%), Apiaceae (9%), and Poaceae (8%), and with genera Thymus, Mentha, Ocimum, Artemisia, Cymbopogon being the most common. The nematicidal activity of EOs primarily arises from their chemical groups, such as terpenes, phenylpropanoids, and organosulfur compounds. 
  • 1.5K
  • 29 Jan 2024
Topic Review
Fungal Enzymes for Polyethylene Terephthalate (PET) Degradation
The ubiquitous persistence of plastic waste in diverse forms and different environmental matrices is one of the main challenges that modern societies are facing at present. The exponential utilization and recalcitrance of synthetic plastics, including polyethylene terephthalate (PET), results in their extensive accumulation, which is a significant threat to the ecosystem. The growing amount of plastic waste ending up in landfills and oceans is alarming due to its possible adverse effects on biota. Thus, there is an urgent need to mitigate plastic waste to tackle the environmental crisis of plastic pollution. With regards to PET, there is a plethora of literature on the transportation route, ingestion, environmental fate, amount, and the adverse ecological and human health effects. Several studies have described the deployment of various microbial enzymes with much focus on bacterial-enzyme mediated removal and remediation of PET. However, there is a lack of consolidated studies on the exploitation of fungal enzymes for PET degradation. Herein, an effort has been made to cover this literature gap by spotlighting the fungi and their unique enzymes, e.g., esterases, lipases, and cutinases. These fungal enzymes have emerged as candidates for the development of biocatalytic PET degradation processes. The first half of this review is focused on fungal biocatalysts involved in the degradation of PET. The latter half explains three main aspects: (1) catalytic mechanism of PET hydrolysis in the presence of cutinases as a model fungal enzyme, (2) limitations hindering enzymatic PET biodegradation, and (3) strategies for enhancement of enzymatic PET biodegradation.
  • 1.5K
  • 26 Nov 2021
Topic Review
Peer Effects in Housing Size in Rural China
In recent decades, rural China has witnessed a housing construction boom. In order to control the rapid growth of rural housing, both central and local governments have established quantitative restrictions on the floor numbers and total housing area; however, these have been relatively ineffective. Current research to explain this rapid growth in rural housing tends to consider independent household behavior, while social interactions among villagers are neglected.
  • 1.5K
  • 10 Feb 2022
Topic Review
Triple-Negative Breast Cancer Molecular Subtyping
Breast cancer (BC) is the most common malignancy affecting women. It is a highly heterogeneous disease broadly defined by the differential expression of cell surface receptors. In the United States, triple negative breast cancer (TNBC) represents 15 to 20% of all BC. When compared with other subtypes of BC, TNBC tends to present in younger women, and has a higher mortality rate of 40% in advanced stages within the first 5 years after diagnosis. TNBC has historically had limited treatment options when compared to other types of BC.
  • 1.5K
  • 09 Mar 2022
Topic Review
Effects of Sound Perception in Plants
Plants have long been considered passive, static, and unchanging organisms, but this view is finally changing. More and more knowledge is showing that plants are aware of their surroundings, and they respond to a surprising variety of stimuli by modifying their growth and development. Plants extensively communicate with the world around them, above and below ground. Although communication through mycorrhizal networks and Volatile Organic Compounds has been known for a long time, acoustic perception and communication are somehow a final frontier of research. Perhaps surprisingly, plants not only respond to sound, they actually seem to emit sound as well. Roots emit audible clicks during growth, and sounds are emitted from xylem vessels, although the nature of these acoustic emissions still needs to be clarified. Even more interesting, there is the possibility that these sounds carry information with ecological implications, such as alerting insects of the hydration state of a possible host plant, and technological implications as well. Monitoring sound emissions could possibly allow careful monitoring of the hydration state of crops, which could mean significantly less water used during irrigation. 
  • 1.5K
  • 08 Oct 2022
Topic Review
Response to Intervention
In education, response to intervention (commonly abbreviated RTI or RtI) is an approach to academic intervention used in the United States to provide early, systematic, and appropriately intensive assistance to children who are at risk for or already underperforming as compared to appropriate grade- or age-level standards. RTI seeks to promote academic success through universal screening, early intervention, frequent progress monitoring, and increasingly intensive research-based instruction or interventions for children who continue to have difficulty. RTI is a multileveled approach for aiding students that is adjusted and modified as needed if they are failing. In terms of identifying students with specific learning disabilities (SLD), RTI was proposed as an alternative to the ability–achievement discrepancy model, which requires children to exhibit a significant discrepancy between their ability (often measured by IQ testing) and academic achievement (as measured by their grades and standardized testing). Methods to identify students with SLD have been controversial for decades and proponents of RTI claim that the process brings more clarity to the Specific Learning Disability (SLD) category of the Individuals with Disabilities Education Improvement Act (IDEA 2004), while opponents claim that RTI simply identifies low achieving students rather than students with learning disabilities.
  • 1.5K
  • 20 Nov 2022
Topic Review
Mediterranean Diet and Male Fertility
Diet has an impact on male reproductive potential, but few studies have focused on the specific impact of food groups or dietary patterns on fertility. Male reproductive health, as indicated by improved semen parameters and increased chances of conceiving, is associated with the Mediterranean diet, while the Western diet is considered a risk factor for male infertility.
  • 1.5K
  • 28 Jun 2023
Topic Review
Hyperuricemia and Chronic Kidney Disease
Hyperuricemia is described as elevated levels of serum uric acid (UA), which is more commonly known as gout, an acute, symptomatic disease where urate crystals deposit in the joint and cause subsequent inflammatory arthritis. Chronic kidney disease (CKD) is defined as abnormalities of the kidney structure or function presented for more than 3 months, according to the Kidney Disease Improving Global Outcome guidelines. Several mechanisms have been identified that explain the relationship between hyperuricemia and chronic kidney disease, including the crystal effect, renin–angiotensin–aldosterone system activation, nitric oxide synthesis inhibition, and intracellular oxidative stress stimulation, and urate-lowering therapy (ULT) has been proven to reduce renal disease progression.
  • 1.5K
  • 09 Aug 2022
Topic Review
Myotonia Congenita
Myotonia congenita (MC) is a rare disorder characterized by stiffness and weakness of the limb and trunk muscles. Mutations in the SCN4A gene encoding the alpha-subunit of the voltage-gated sodium channel Nav1.4 have been reported to be responsible for sodium channel myotonia (SCM). The Nav1.4 channel is expressed in skeletal muscles, and its related channelopathies affect skeletal muscle excitability, which can manifest as SCM, paramyotonia, and periodic paralysis. In this study, the missense mutation p.V445M was identified in two individual families with MC. To determine the functional consequences of having a mutated Nav1.4 channel, whole-cell patch-clamp recording of transfected Chinese hamster ovary cells was performed. Evaluation of the transient Na+ current found that a hyperpolarizing shift occurs at both the activation and inactivation curves with an increase of the window currents in the mutant channels. The Nav1.4 channel’s co-expression with the Navβ4 peptide can generate resurgent Na+ currents at repolarization following a depolarization. The magnitude of the resurgent currents is higher in the mutant than in the wild-type (WT) channel. Although the decay kinetics are comparable between the mutant and WT channels, the time to the peak of resurgent Na+ currents in the mutant channel is significantly protracted compared with that in the WT channel. These findings suggest that the p.V445M mutation in the Nav1.4 channel results in an increase of both sustained and resurgent Na+ currents, which may contribute to hyperexcitability with repetitive firing and is likely to facilitate recurrent myotonia in SCM patients.
  • 1.5K
  • 29 Oct 2020
Topic Review
Gellan
Gellan is a water-soluble gum that structurally exists as a tetrasaccharide comprised of 20% glucuronic acid, 60% glucose and 20% rhamnose, for which various food, non-food and biomedical applications have been reported.
  • 1.5K
  • 08 May 2021
Topic Review
Tungsten in Soil
Tungsten (W) occurs naturally in soils and the Earth’s crust is the most important source of this element. Tungsten reserves have been estimated to be approximately 3.1 Mt in ore deposits, where the metal exists mainly as a component of several minerals, such as wolframite (Fe, MnWO4) and scheelite (CaWO4).
  • 1.5K
  • 26 Jul 2021
Topic Review
Sustainable Entrepreneurship
Sustainable entrepreneurship is venturing to shift business practices towards environmental and social sustainability. It gained popularity worldwide, particularly in the US and Europe, due to promoting regulations for some sustainability areas, the availability of impact investment, and the large-scale entrepreneurial ecosystem of the country.
  • 1.5K
  • 06 Apr 2022
Topic Review
Heating, Ventilation, and Air Conditioning System
The heating, ventilation, and air conditioning (HVAC) system is a major energy consumer in office buildings, and its operation is critical for indoor thermal comfort.
  • 1.5K
  • 24 Jun 2022
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