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Topic Review
Nrf2 and Alzheimer’s Disease
Nuclear factor erythroid 2-related factor 2 (Nrf2) is an important transcription factor that reduces oxidative stress. When reactive oxygen species (ROS) or reactive nitrogen species (RNS) are detected, Nrf2 translocates from the cytoplasm into the nucleus and binds to the antioxidant response element (ARE), which regulates the expression of antioxidant and anti-inflammatory genes. Nrf2 impairments are observed in the majority of neurodegenerative disorders, including Alzheimer’s disease (AD). The classic hallmarks of AD include β-amyloid (Aβ) plaques, and neurofibrillary tangles (NFTs). Oxidative stress is observed early in AD and is a novel therapeutic target for the treatment of AD. The nuclear translocation of Nrf2 is impaired in AD compared to controls. Increased oxidative stress is associated with impaired memory and synaptic plasticity. The administration of Nrf2 activators reverses memory and synaptic plasticity impairments in rodent models of AD. Therefore, Nrf2 activators are a potential novel therapeutic for neurodegenerative disorders including AD. 
  • 1.7K
  • 10 Aug 2021
Topic Review
Invasive Water Hyacinth
Water hyacinth, or Eichhornia crassipes (Mart.) Solms, from the family Pontederiaceae, is a free-floating aquatic plant that commonly grows in inland freshwater bodies such as lakes, rivers, streams, ponds and wetlands. The plant has broad, wide canopy-like waxy leaves and purple clustered flowers that grow in spikes. The petioles of the plant appear bulbous with air-sacs that help make it buoyant. The plant varies in height from a few centimetres to nearly a metre, while the leaves may be around 15–20 cm in length and width. The plant can sometimes become rooted when it lodges in muddy, shallow waters and the flowers may be blue or white. With the ability to reproduce both sexually through seed propagation and asexually through stolon vegetative reproduction, water hyacinth exhibits the reproductive characteristics suited to invasive success. 
  • 1.7K
  • 11 Aug 2021
Topic Review
Adsorption of Pesticides onto Clay Minerals
Adsorption of pesticides onto natural clay mineral relies on the use of adsorbents with minimal treatment beyond their preparation to provide a narrow size distribution and homoionic form by exchanging the naturally occurring interlamellar cations (in the case of smectites) by some alkaline (Na+ or K+) or alkaline earth (Ca2+or Mg2+) cation. Additional modifications include organophilization, intercalation with metal polycations and pillaring.  The adsorption capacity and strength of pesticides onto homoionic, organophilic and intercalated/pillared clay minerals depend on the chemical nature of the pesticide, surface area, and pore volume. Electrostatic interactions, hydrogen and coordinative bonds, surface complexations, and hydrophobic associations are the main interactions between pesticides and clay minerals.
  • 1.7K
  • 29 Nov 2021
Topic Review
Nanostructured Antibiotics
Bacterial strains resistant to antimicrobial treatments, such as antibiotics, have emerged as serious clinical problems, necessitating the development of novel bactericidal materials. Nanostructures with particle sizes ranging from 1 to 100 nanometers have appeared recently as novel antibacterial agents, which are also known as “nanoantibiotics”. Nanomaterials have been shown to exert greater antibacterial effects on Gram-positive and Gram-negative bacteria across several studies. Antibacterial nanofilms for medical implants and restorative matters to prevent bacterial harm and antibacterial vaccinations to control bacterial infections are examples of nanoparticle applications in the biomedical sectors. The development of unique nanostructures, such as nanocrystals and nanostructured materials, is an exciting step in alternative efforts to manage microorganisms because these materials provide disrupted antibacterial effects, including better biocompatibility, as opposed to minor molecular antimicrobial systems, which have short-term functions and are poisonous.
  • 1.7K
  • 10 Nov 2022
Topic Review
Traumatic Memories
The management of traumatic memories is important when treating mental health disorders such as post traumatic stress disorder. Traumatic memories can cause life problems even to individuals who do not meet the diagnostic criteria for a mental health disorder. They result from traumatic experiences, including natural disasters such as earthquakes and tsunamis; violent events such as kidnapping, terrorist attacks, war, domestic abuse and rape. Traumatic memories are naturally stressful in nature and emotionally overwhelm people's existing coping mechanisms. When simple objects such as a photograph, or events such as a birthday party, bring traumatic memories to mind people often try to bar the unwanted experience from their minds so as to proceed with life, with varying degrees of success. The frequency of these reminders diminish over time for most people. There are strong individual differences in the rate at which the adjustment occurs. For some the number of intrusive memories diminish rapidly as the person adjusts to the situation, whereas for others intrusive memories may continue for decades with significant interference to their mental, physical and social well being. Several psychotherapies have been developed that change, weaken, or prevent the formation of traumatic memories. Pharmacological methods for erasing traumatic memories are currently the subject of active research. The ability to erase specific traumatic memories, even if possible, would create additional problems and so would not necessarily benefit the individual.
  • 1.7K
  • 17 Oct 2022
Topic Review
Hockey Stick Graph
Hockey stick graphs present the global or hemispherical mean temperature record of the past 500 to 2000 years as shown by quantitative climate reconstructions based on climate proxy records. These reconstructions have consistently shown a slow long term cooling trend changing into relatively rapid warming in the 20th century, with the instrumental temperature record by 2000 exceeding earlier temperatures. The term "hockey stick graph" was popularized by the climatologist Jerry Mahlman, to describe the pattern shown by the Mann, Bradley & Hughes 1999 (MBH99) reconstruction, envisaging a graph that is relatively flat with a downward trend to 1900 as forming an ice hockey stick's "shaft" followed by a sharp, steady increase corresponding to the "blade" portion. The reconstructions have featured in Intergovernmental Panel on Climate Change (IPCC) reports as evidence of global warming. Arguments over the reconstructions have been taken up by fossil fuel industry funded lobbying groups attempting to cast doubt on climate science. Paleoclimatology dates back to the 19th century, and the concept of examining varves in lake beds and tree rings to track local climatic changes was suggested in the 1930s. In the 1960s, Hubert Lamb generalised from historical documents and temperature records of central England to propose a Medieval Warm Period from around 900 to 1300, followed by Little Ice Age. This was the basis of a "schematic diagram" featured in the IPCC First Assessment Report of 1990 beside cautions that the medieval warming might not have been global. The use of indicators to get quantitative estimates of the temperature record of past centuries was developed, and by the late 1990s a number of competing teams of climatologists found indications that recent warming was exceptional. Bradley & Jones 1993 introduced the "Composite Plus Scaling" (CPS) method which, as of 2009, was still being used by most large-scale reconstructions. Their study was featured in the IPCC Second Assessment Report of 1995. In 1998 Michael E. Mann, Raymond S. Bradley and Malcolm K. Hughes developed new statistical techniques to produce Mann, Bradley & Hughes 1998 (MBH98), the first eigenvector-based climate field reconstruction (CFR). This showed global patterns of annual surface temperature, and included a graph of average hemispheric temperatures back to 1400 with shading emphasising that uncertainties (to two standard error limits) were much greater in earlier centuries. Jones et al. 1998 independently produced a CPS reconstruction extending back for a thousand years, and Mann, Bradley & Hughes 1999 (MBH99) used the MBH98 methodology to extend their study back to 1000. A version of the MBH99 graph was featured prominently in the 2001 IPCC Third Assessment Report (TAR), which also drew on Jones et al. 1998 and three other reconstructions to support the conclusion that, in the Northern Hemisphere, the 1990s was likely to have been the warmest decade and 1998 the warmest year during the past 1,000 years. The graph became a focus of dispute for those opposed to the strengthening scientific consensus that late 20th century warmth was exceptional. In 2003, as lobbying over the 1997 Kyoto Protocol intensified, a paper claiming greater medieval warmth was quickly dismissed by scientists in the Soon and Baliunas controversy. Later in 2003, Stephen McIntyre and Ross McKitrick published McIntyre & McKitrick 2003b disputing the data used in MBH98 paper. In 2004 Hans von Storch published criticism of the statistical techniques as tending to underplay variations in earlier parts of the graph, though this was disputed and he later accepted that the effect was very small. In 2005 McIntyre and McKitrick published criticisms of the principal components analysis methodology as used in MBH98 and MBH99. Their analysis was subsequently disputed by published papers including Huybers 2005 and Wahl & Ammann 2007 which pointed to errors in the McIntyre and McKitrick methodology. Political disputes led to the formation of a panel of scientists convened by the United States National Research Council, their North Report in 2006 supported Mann's findings with some qualifications, including agreeing that there were some statistical failings but these had little effect on the result. More than two dozen reconstructions, using various statistical methods and combinations of proxy records, support the broad consensus shown in the original 1998 hockey-stick graph, with variations in how flat the pre-20th century "shaft" appears. The 2007 IPCC Fourth Assessment Report cited 14 reconstructions, 10 of which covered 1,000 years or longer, to support its strengthened conclusion that it was likely that Northern Hemisphere temperatures during the 20th century were the highest in at least the past 1,300 years. Further reconstructions, including Mann et al. 2008 and PAGES 2k Consortium 2013, have supported these general conclusions.
  • 1.7K
  • 10 Nov 2022
Topic Review
Mammoth Mountain
Mammoth Mountain is a lava dome complex partially located within the town of Mammoth Lakes, California, in the Inyo National Forest of Madera and Mono Counties. It is home to a large ski area primarily on the Mono County side. Mammoth Mountain was formed in a series of eruptions that ended 57,000 years ago. Mammoth still produces hazardous volcanic gases that kill trees and caused ski patroller fatalities in 2006.
  • 1.7K
  • 01 Dec 2022
Topic Review
Pleiotropic Anticancer of Withaferin A
Withaferin A, a natural bioactive molecule isolated from the Indian medicinal plant Withania somnifera (L.) Dunal, has been reported to impart anticancer activities against various cancer cell lines and preclinical cancer models by modulating the expression and activity of different oncogenic proteins.
  • 1.7K
  • 16 Feb 2023
Topic Review
Detection of Rootkits Using Memory Analysis
Rootkits are malicious programs designed to conceal their activities on compromised systems, making them challenging to detect using conventional methods. As the threat landscape continually evolves, rootkits pose a serious threat by stealthily concealing malicious activities, making their early detection crucial to prevent data breaches and system compromise. A promising strategy for monitoring system activities involves analyzing volatile memory. The process can be made more reliable by the use of Machine learning and deep learning algorithms too.
  • 1.7K
  • 12 Oct 2023
Topic Review
ITS2 Secondary Structure
The secondary structure of ribosomal internal transcribed spacer 2 (ITS2) 
  • 1.7K
  • 22 Sep 2020
Topic Review
Hypoxia-Inducible Factor
The hypoxia signalling pathway enables adaptation of cells to decreased oxygen availability. When oxygen becomes limiting, the central transcription factors of the pathway, hypoxia-inducible factors (HIFs), are stabilised and activated to induce the expression of hypoxia-regulated genes, thereby maintaining cellular homeostasis.
  • 1.7K
  • 18 Jan 2021
Topic Review
Human Immunodeficiency Virus Type 1
Human Immunodeficiency Virus type 1 (HIV-1) is a lentivirus containing two RNA genomes that must be reverse transcribed into double-stranded DNA and then integrated into the host genome to ensure a productive infection. HIV-1 can infect host CD4+ T cells and macrophages, resulting in CD4+ T cell loss and immune dysfunction that leads to the acquired immune deficiency syndrome (AIDS).
  • 1.7K
  • 23 Mar 2021
Topic Review
Delamination-and Electromigration-Related Failures
The reliability of photovoltaic (PV) modules operating under various weather conditions attracts the manufacturer’s concern since several studies reveal a degradation rate higher than 0.8% per year for the silicon-based technology and reached up to 2.76% per year in a harsh climate. The lifetime of the PV modules is decreased because of numerous degradation modes. Electromigration and delamination are two failure modes that play a significant role in PV modules’ output power losses. The correlations of these two phenomena are not sufficiently explained and understood like other failures such as corrosion and potential-induced degradation. 
  • 1.7K
  • 30 Jun 2021
Topic Review
Lichen Biomonitoring in Forests
Forest ecosystems are often located in remote areas, far from direct sources of air pollution. Nonetheless, they may be affected by different types of atmospheric deposition, which can compromise their health and inner balance. Epiphytic lichens respond to air pollution and climate change, and they have been widely adopted as ecological indicators, mainly in urban and industrial areas, while forest ecosystems are still underrepresented. 
  • 1.7K
  • 31 Mar 2023
Topic Review
Specialized Pro-Resolving Mediators in Neuroinflammation
Specialized pro-resolving mediators (SPMs) are lipid mediators derived from poly-unsaturated fatty acids (PUFAs) which have been demonstrated to play an important role in the inflammation environment, preventing an overreaction of the organism and promoting the resolution of inflammation.
  • 1.7K
  • 10 Aug 2022
Topic Review
Adsorptive Membrane for Boron Removal
The complexity of removing boron compounds from aqueous systems has received serious attention among researchers and inventors in the water treating industry. This is due to the higher level of boron in the aquatic ecosystem, which is caused by the geochemical background and anthropogenic factors. The gradual increase in the distribution of boron for years can become extremely toxic to humans, terrestrial organisms and aquatic organisms. Numerous methods of removing boron that have been executed so far can be classified under batch adsorption, membrane-based processes and hybrid techniques. Conventional water treatments such as coagulation, sedimentation and filtration do not significantly remove boron, and special methods would have to be installed in order to remove boron from water resources. The blockage of membrane pores by pollutants in the available membrane technologies not only decreases their performance but can make the membranes prone to fouling. Therefore, the surface-modifying flexibility in adsorptive membranes can serve as an advantage to remove boron from water resources efficiently. These membranes are attractive because of the dual advantage of adsorption/filtration mechanisms. 
  • 1.7K
  • 05 Sep 2022
Topic Review
Shuttle-Derived Launch Vehicle
Shuttle-Derived Launch Vehicle (SDLV), or simply Shuttle-Derived Vehicle (SDV), is a term describing one of an array of concepts that have been developed for building space launch vehicles using the already developed components, technology, and infrastructure of the Space Shuttle program. In the late 1980s and early 1990s, NASA formally studied a cargo-only vehicle, Shuttle-C, that would have supplemented the crewed Space Shuttle. In 2005, NASA was developing the Ares I and Ares V launch vehicles, based in part on highly modified Shuttle components, to enable exploration of the Moon and Mars. The agency also studied a third such vehicle, the Ares IV.
  • 1.7K
  • 29 Nov 2022
Topic Review
ZEB Family
Molecular signaling pathways involved in cancer have been intensively studied due to their crucial role in cancer cell growth and dissemination. Among them, zinc finger E-box binding homeobox-1 (ZEB1) and -2 (ZEB2) are molecules that play vital roles in signaling pathways to ensure the survival of tumor cells, particularly through enhancing cell proliferation, promoting cell migration and invasion, and triggering drug resistance. Importantly, ZEB proteins are regulated by microRNAs (miRs). In this review, we demonstrate the impact that miRs have on cancer therapy, through their targeting of ZEB proteins. MiRs are able to act as onco-suppressor factors and inhibit the malignancy of tumor cells through ZEB1/2 down-regulation. This can lead to an inhibition of EMT mechanism, therefore reducing metastasis. Also, miRs are able to inhibit ZEB1/2-mediated drug resistance and immunosuppression. Additionally, we explore the upstream modulators of miRs such as long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs), as these regulators can influence the inhibitory effect of miRs on ZEB proteins and cancer progression.
  • 1.7K
  • 19 Jul 2020
Topic Review
Convection Enhanced Delivery
Convection enhanced delivery (CED), first described by Bobo et al. in 1994, remains a promising technique for circumventing the Blood Brain Barrier (BBB) and delivering therapy in a non-diffusion dependent manner, thereby facilitating high local concentrations of infusate.
  • 1.7K
  • 12 Jan 2021
Topic Review
Nature Time and Pro-environmental Attitudes/Behaviors
Urbanization, screen dependency, and the changing nature of childhood and parenting have led to increased time indoors, creating physical and emotional distancing from nature and time spent in natural environments. Substantial evidence from observational and intervention studies indicates that overall time spent in nature leads to increased perceived value for connectedness to nature and, subsequently, greater pro-environmental attitudes and behaviors (PEAB).
  • 1.7K
  • 30 Sep 2021
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