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Topic Review
Naturally Occurring Heavy Metal Hyperaccumulators
A hyperaccumulator is a plant which can absorb and accumulate heavy metals in its above-ground sections (especially the leaves) at values exceeding specific metal thresholds. 
  • 1.4K
  • 21 Sep 2022
Topic Review
Myocardial Injury Related to SARS-CoV-2 Pneumonia
The diagnosis of SARS-CoV-2 pneumonia is expected to worsen, and mortality will be higher when combined with myocardial injury (MI). The combination of novel coronavirus infections in patients with MI can cause confusion in diagnosis and assessment, with each condition exacerbating the other, and increasing the complexity and difficulty of treatment.
  • 1.4K
  • 08 Oct 2022
Topic Review
Head Direction Cells
Head direction cells are type of neuron involved in spatial processing. Head direction (HD) cells are neurons found in a number of brain regions that increase their firing rates above baseline levels only when the animal's head points in a specific direction. They have been reported in rats, monkeys, mice, chinchillas and bats, but are thought to be common to all mammals, perhaps all vertebrates and perhaps even some invertebrates, and to underlie the "sense of direction". When the animal's head is facing in the cell's "preferred firing direction" these neurons fire at a steady rate (i.e., they do not show adaptation), but firing decreases back to baseline rates as the animal's head turns away from the preferred direction (usually about 45° away from this direction). HD cells are found in many brain areas, including the cortical regions of postsubiculum (also known as the dorsal presubiculum), retrosplenial cortex, and entorhinal cortex, and subcortical regions including the thalamus (the anterior dorsal and the lateral dorsal thalamic nuclei), lateral mammillary nucleus, dorsal tegmental nucleus and striatum. It is thought that the cortical head direction cells process information about the environment, while the subcortical ones process information about angular head movements. A striking characteristic of HD cells is that in most brain regions they maintain the same relative preferred firing directions, even if the animal is moved to a different room, or if landmarks are moved. This has suggested that the cells interact so as to maintain a unitary stable heading signal (see "Theoretical models"). Recently, however, a subpopulation of HD neurons has been found in the dysgranular part of retrosplenial cortex that can operate independently of the rest of the network, and which seems more responsive to environmental cues. The system is related to the place cell system, located in the hippocampus, which is mostly orientation-invariant and location-specific, whereas HD cells are mostly orientation-specific and location-invariant. However, HD cells do not require a functional hippocampus to express their head direction specificity. They depend on the vestibular system, and the firing is independent of the position of the animal's body relative to its head. Some HD cells exhibit anticipatory behaviour: the best match between HD activity and the animal's actual head direction has been found to be up to 95 ms in future. That is, activity of head direction cells predicts, 95 ms in advance, what the animal's head direction will be. This possibly reflects inputs from the motor system ("motor efference copy") preparing the network for an impending head turn. HD cells continue to fire in an organized manner during sleep, as if animals were awake. However, instead of always pointing toward the same direction—the animals are asleep and thus immobile—the neuronal "compass needle" moves constantly. In particular, during rapid eye movement sleep, a brain state rich in dreaming activity in humans and whose electrical activity is virtually indistinguishable from the waking brain, this directional signal moves as if the animal is awake: that is, HD neurons are sequentially activated, and the individual neurons representing a common direction during wake are still active, or silent, at the same time.
  • 1.4K
  • 16 Nov 2022
Topic Review
Comparison of High Definition Optical Disc Formats
This article compares the technical specifications of multiple high definition formats, including HD DVD and Blu-ray Disc; two mutually incompatible, high definition optical disc formats that, beginning in 2006, attempted to improve upon and eventually replace the DVD standard. The two formats remained in a format war until February 19, 2008 when Toshiba, HD DVD's creator, announced plans to cease development, manufacturing and marketing of HD DVD players and recorders. Other high-definition optical disc formats were attempted, including the multi-layered red-laser Versatile Multilayer Disc and a Chinese made format called EVD. Both appear to have been abandoned by their respective developers.
  • 1.4K
  • 15 Nov 2022
Topic Review
Morpha
In biology, polymorphism is the occurrence of two or more clearly different morphs or forms, also referred to as alternative phenotypes, in the population of a species. To be classified as such, morphs must occupy the same habitat at the same time and belong to a panmictic population (one with random mating). Put simply, polymorphism is when there are two or more possibilities of a trait on a gene. For example, there is more than one possible trait in terms of a jaguar's skin colouring; they can be light morph or dark morph. Due to having more than one possible variation for this gene, it is termed 'polymorphism'. However, if the jaguar has only one possible trait for that gene, it would be termed "monomorphic". For example, if there was only one possible skin colour that a jaguar could have, it would be termed monomorphic. The term polyphenism can be used to clarify that the different forms arise from the same genotype. Genetic polymorphism is a term used somewhat differently by geneticists and molecular biologists to describe certain mutations in the genotype, such as single nucleotide polymorphisms that may not always correspond to a phenotype, but always corresponds to a branch in the genetic tree. See below. Polymorphism is common in nature; it is related to biodiversity, genetic variation, and adaptation. Polymorphism usually functions to retain a variety of forms in a population living in a varied environment.:126 The most common example is sexual dimorphism, which occurs in many organisms. Other examples are mimetic forms of butterflies (see mimicry), and human hemoglobin and blood types. According to the theory of evolution, polymorphism results from evolutionary processes, as does any aspect of a species. It is heritable and is modified by natural selection. In polyphenism, an individual's genetic makeup allows for different morphs, and the switch mechanism that determines which morph is shown is environmental. In genetic polymorphism, the genetic makeup determines the morph. The term polymorphism also refers to the occurrence of structurally and functionally more than two different types of individuals, called zooids, within the same organism. It is a characteristic feature of cnidarians. For example, Obelia has feeding individuals, the gastrozooids; the individuals capable of asexual reproduction only, the gonozooids, blastostyles; and free-living or sexually reproducing individuals, the medusae. Balanced polymorphism refers to the maintenance of different phenotypes in population.
  • 1.4K
  • 11 Nov 2022
Topic Review
Resilience in the Built Environment
Resilience in the Built Environment is the built environment's capability to keep adapting to existing and emerging threats such as severe wind storms or earthquakes and creating robustness and redundancy in building design. New implications of changing conditions on the efficiency of different approaches to design and planning can be addressed in the following term.
  • 1.4K
  • 18 Nov 2022
Topic Review
Role of Pyroptosis in Intervertebral Disc Degeneration
Intervertebral disc degeneration (IDD), a progressive and multifactorial pathological process, is predominantly associated with low back pain and permanent disability. Pyroptosis is a type of lytic programmed cell death triggered by the activation of inflammasomes and caspases. Unlike apoptosis, pyroptosis is characterized by the rupture of the plasma membrane and the release of inflammatory mediators, accelerating the destruction of the extracellular matrix (ECM). Recent studies have shown that pyrin domain-containing 3 (NLRP3) inflammasome-mediated pyroptosis in nucleus pulposus (NP) cells is activated in the progression of IDD. Furthermore, targeting pyroptosis in IDD demonstrates the excellent capacity of ECM remodeling and its anti-inflammatory properties, suggesting that pyroptosis is involved in the IDD process. Here, the molecular mechanism of pyroptosis and the pathogenesis of IDD are briefly summarized. Researchers also focus on the role of pyroptosis in the pathological progress of IDD and its targeted therapeutic application.
  • 1.4K
  • 20 Dec 2022
Topic Review
Control Strategies of the Major Soilborne Fungal/Oomycete Diseases
Globally, tomato is the second most cultivated vegetable crop next to potato, preferentially grown in temperate climates. Processing tomatoes are generally produced in field conditions, in which soilborne pathogens have serious impacts on tomato yield and quality by causing diseases of the tomato root system. Major processing tomato-producing countries have documented soilborne diseases caused by a variety of pathogens including bacteria, fungi, nematodes, and oomycetes, which are of economic importance and may threaten food security. Surveys in the Australian processing tomato industry showed that plant growth and yield were significantly affected by soilborne pathogens, especially Fusarium oxysporum and Pythium species. Globally, different management methods have been used to control diseases such as the use of resistant tomato cultivars, the application of fungicides, and biological control. Among these methods, biocontrol has received increasing attention due to its high efficiency, target-specificity, sustainability and public acceptance. The application of biocontrol is a mix of different strategies, such as applying antagonistic microorganisms to the field, and using the beneficial metabolites synthesized by these microorganisms. 
  • 1.4K
  • 16 Feb 2023
Topic Review
Autophagy-ER Stress Axis in High Fat/Carbohydrate Diet-Induced Nonalcoholic Fatty Liver Disease
Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease that can progress from simple hepatic steatosis to nonalcoholic steatohepatitis (NASH), and even further to liver cirrhosis or liver cancer. Overconsumption of high fat and/or carbohydrate are among the most common lifestyle factors that drive the development and progression of NAFLD. This review evaluates recent reports on the involvement of autophagy and endoplasmic reticulum (ER) stress in the pathogenesis of NAFLD. Here, we reveal a mechanism of an intrinsically linked axis of impaired autophagy and unresolved ER stress that mediates the development and progression of NAFLD resulting from the overconsumption of high fat and/or carbohydrate.
  • 1.4K
  • 05 Nov 2020
Topic Review
CO2 Sequestration in Geological Formations
The geological storage of carbon dioxide (CO2) is the most effective and, in many cases, the only viable short- to medium-term alternative for considerably moving towards CO2 sequestration in geological sinks and, thus, lowering net carbon emissions into the atmosphere.
  • 1.4K
  • 04 Nov 2022
Topic Review
Catalysis for Biogas Steam Reforming
Hydrogen production from natural gas or biogas, at different purity levels, has emerged as an important technology with continuous development and improvement in order to stand for sustainable and clean energy. Regarding biogas, which can be obtained from multiple sources, hydrogen production through the steam reforming of methane is one of the most important methods for its energy use. In that sense, the role of catalysts to make the process more efficient is crucial, normally contributing to a higher hydrogen yield under milder reaction conditions in the final product.
  • 1.4K
  • 11 Dec 2023
Topic Review
Abscisic Acid (ABA)
Abscisic acid (ABA) is a significant regulator of numerous flexible traits of plant developmental improvements, including embryo maturation, germination, seed dormancy, floral initiation, and root growth.
  • 1.4K
  • 25 Aug 2021
Topic Review
Methods of Manufacture of Lipid Nanoparticles
Lipid nanoparticles (LNPs) have gained prominence as primary carriers for delivering a diverse array of therapeutic agents. Biological products have achieved a solid presence in clinical settings, and the anticipation of creating novel variants is increasing. These products predominantly encompass therapeutic proteins, nucleic acids and messenger RNA. The advancement of efficient LNP-based delivery systems for biologics that can overcome their limitations remains a highly favorable formulation strategy. 
  • 1.4K
  • 31 Jan 2024
Topic Review
Mechanisms of α-Syn Aggregation In Vitro
The aggregation of proteins into amyloid fibers is linked to more than forty still incurable cellular and neurodegenerative diseases such as Parkinson’s disease (PD), multiple system atrophy, Alzheimer’s disease and type 2 diabetes, among others. The process of amyloid formation is a main feature of cell degeneration and disease pathogenesis. Despite being methodologically challenging, a complete understanding of the molecular mechanism of aggregation, especially in the early stages, is essential to find new biological targets for innovative therapies. Here, chemical and biophysical methodologies that provided insights on Alpha-synuclein aggregation that would help to investigate other less-known aggregation-prone peptides and proteins were presented.
  • 1.4K
  • 03 Jan 2023
Topic Review
Agricultural Water
Monitoring the microbial quality of water used in agriculture is important to reduce the likelihood of produce contamination and possible future foodborne outbreaks. The U.S. Food and Drug Administration has established the Produce Safety Rule as part of the Food Safety Modernization Act to improve the safety of produce that is normally consumed raw during growing, harvesting, packing and holding activities. In order to comply with the rule, growers need to follow some standards for the microbial quality of water that is used on the produce field, however, more information on the water microbial profile is necessary in order to improve the accuracy of the testing.
  • 1.4K
  • 11 Jan 2022
Topic Review
Acrylic Carrier
Wood used outdoor is subjected to different sources of degradation and should be protected properly. In this study, acrylic resins were added to a wood impregnation system using amine oxides and propiconazole, an organic fungicide, to create a two-part wood protection preservation treatment. Since amine oxides can diffuse readily into wood, this treatment protected both the surface and inner structure of the treated wood following a simple dipping. Many aspects of the treatment were studied: the adhesion of the acrylic coatings, their permeability to water, and the impregnation depth of the propiconazole. In each case, a particular attention was accorded to the interactions between the resins and the impregnation system. Adhesion and permeability tests were coupled with an artificial aging process simulating severely wet conditions. Amine oxides reduced the adhesion of the coatings, but did not impair their aging properties. Because of their hydrophilic nature, they also increased the permeability to liquid water, although they did not affect the air moisture permeability. The penetration of the propiconazole, estimated with a dye, decreased with the resin. Overall, the two parts of the treatment lightly impaired each other, but the practical aspect of this treatment may overcome these disadvantages.
  • 1.4K
  • 30 Oct 2020
Topic Review
Sequrity aspects in Smart Meters
Smart meters are of the basic elements in the so-called Smart Grid. These devices, connected to the Internet, keep bidirectional communication with other devices in the Smart Grid structure to allow remote readings and maintenance. As any other device connected to a network, smart meters become vulnerable to attacks with different purposes, like stealing data or altering readings. Nowadays, it is becoming more and more popular to buy and plug-and-play smart meters, additionally to those installed by the energy providers, to directly monitor the energy consumption at home. This option inherently entails security risks that are under the responsibility of householders. In this paper, we focus on an open solution based on Smartpi 2.0 devices with two purposes. On the one hand, we propose a network configuration and different data flows to exchange data (energy readings) in the home. These flows are designed to support collaborative among the devices in order to prevent external attacks and attempts of corrupting the data. On the other hand, we check the vulnerability by performing two kind of attacks (denial of service and stealing and changing data by using a malware).
  • 1.4K
  • 27 Oct 2020
Topic Review
Arenaviridae Nucleoprotein
Arenaviridae is a family of viruses harbouring important emerging pathogens belonging to the Bunyavirales order. Like in other segmented negative strand RNA viruses, the nucleoprotein (NP) is a major actor of the viral life cycle being both (i) the necessary co-factor of the polymerase present in the L protein, and (ii) the last line of defence of the viral genome (vRNA) by physically hiding its presence in the cytoplasm. The NP is also one of the major players interfering with the immune system. Several structural studies of NP have shown that it features two domains: a globular RNA binding domain (NP-core) in its N-terminal and an exonuclease domain (ExoN) in its C-terminal. Further studies have observed that significant conformational changes are necessary for RNA encapsidation. We here present the architecture and latest structural data available on Arenaviridae NP.  
  • 1.4K
  • 27 Jul 2020
Topic Review
Human Coronavirus (HCoV)
Coronaviruses (CoVs) were identified in the 1930s as zoonotic spherical pathogens causing mostly respiratory or enteric diseases. Coronaviruses vary in size and are enveloped with club-shaped spikes on their surface. A helically symmetrical nucleocapsid comprising positive-sense single-stranded RNA is one of the largest virus genomes, ranging from 26 to 32 kilobases in length. Although CoVs are distributed mainly among mammals and birds, since 1960 seven species of human coronaviruses (HCoVs) have been described and some HCoVs infections (SARS-CoV, MERS-CoV and SARS-CoV-2) have resulted in lethal epidemics. The global range and high fatality rate of the newest HCoV pandemic has made SARS-CoV-2 the focus of the scientific world.
  • 1.4K
  • 17 Dec 2020
Topic Review
Looking for Metropolitan ecological area
       Compact housing structures located in city centers are considered to be the most energy and environmentally effective, mainly due to the access to services, transport networks and municipal infrastructures. There is the question how to look for metropolitan ecologacl areas and why so many of the acknowledged ecological housing complexes are located on the outskirts of cities or suburbs and . Numerous cities decide to introduce strategies either to densify city centers, hoping to improve energy efficiency. The Tricity Metropolitan Area is a special case undergoing dynamic transformation, and its development overlaps with the processes of both planned densification of the center as well as uncontrolled suburbanization.  The goal  was to find the correlation between optimal location of an eco-district from the functional center of the Tricity Metropolitan Area, allowing for the most favorable energy and environmental parameters related both to the architectural and urban scale. The research was conducted in four different scenarios, concerning present and future development. In these scenarios, specific locations were examined, and the following were compared: total energy consumption, ecological footprint and CO2 lifecycle emissions. This study showed the possibility for suburban housing complexes with appropriate parameters in an edge city model to have the same or better results than complexes situated closer to the functional center of the city. This is mainly due to the building’s energy efficiency, sustainable mobility, municipal infrastructure and relevant service access. The research proves the importance of implementing sustainable energy-saving and environmentally oriented activities at both an architectural and urban scale planning process.
  • 1.4K
  • 29 Oct 2020
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