New Approach for Temporal Stability Evaluation of Pseudo-Invariant Calibration Sites (PICS)

Pseudo-Invariant Calibration Sites (PICS) are one of the most popular methods for in-flight vicarious radiometric calibration of Earth remote sensing satellites. The fundamental question of PICS temporal stability has not been adequately addressed. However, the main purpose of this work is to evaluate the temporal stability of a few PICS using a new approach. The analysis was performed over six PICS (Libya 1, Libya 4, Niger 1, Niger 2, Egypt 1 and Sudan 1). The concept of a Virtual Constellation was developed to provide greater temporal coverage and also to overcome the dependence limitation of any specific characteristic derived from one particular sensor. TOA reflectance data from four sensors consistently demonstrating stable calibration to within 5%the Landsat 7 ETM+ (Enhanced Thematic Mapper Plus), Landsat 8 OLI (Operational Land Imager), Terra MODIS (Moderate Resolution Imaging Spectroradiometer) and Sentinel-2A MSI (Multispectral Instrument)were merged into a seamless dataset. Instead of using the traditional method of trend analysis (Students T test), a nonparametric Seasonal Mann-Kendall test was used for determining the PICS stability. The analysis results indicate that Libya 4 and Egypt 1 do not exhibit any monotonic trend in six reflective solar bands common to all of the studied sensors, indicating temporal stability. A decreasing monotonic trend was statistically detected in all bands, except SWIR 2, for Sudan 1 and the Green and Red bands for Niger 1. An increasing trend was detected in the Blue band for Niger 2 and the NIR band for Libya 1. These results do not suggest abandoning PICS as a viable calibration source. Rather, they indicate that PICS temporal stability cannot be assumed and should be regularly monitored as part of the sensor calibration process

In-silico designing of a potent ligand molecule against PTEN (Phosphatase and tensin homolog) implicated in Breast Cancer

Breast cancer has been attributed to be the second most common malignancy in females worldwide after skin cancer associated with a significantly high mortality rate. Tumor suppressor genes have an indispensable role in maintaining genomic integrity as well as cell cycle regulation. Phosphatase and tensin homolog deleted on chromosome ten (PTEN) is one of the most frequently mutated human tumor suppressor genes, implicated in cell growth, survival, and suppressing tumor formation. As the tumor progresses to more advanced stages, genetic alterations tend to increase one such alteration is the mutation of the PTEN gene which is linked to programmed cell death and maintenance of cell cycle regulation. There is a syndrome known as Cowden syndrome associated with a high risk of breast cancer which is a result of an outcome of germline mutations in the PTEN gene. Loss of PTEN activity, either at the protein or genomic level, has been related to many primary and metastatic malignancies including breast cancer. This study focuses on developing a potential bioavailable ligand inhibitory molecule for PTEN, using a computer-aided drug design approach (CADD). A library of developed ligands consisting of 50 potential molecules was screened to find a potential candidate to be used for second generation drug development. Among them, LIG28 was adjudged as the most effective and potential PTEN inhibitor given its maximum binding affinity of ΔG -5.96Kcal/mole with a lower RMSD value. Carmer’s Rule of toxicity further revealed the compatibility and non-toxicity of the molecule. These observations underscore the importance of PTEN as a target in the development of tumorigenesis and the prognosis of breast cancer

Molecular Docking studies of Apigenin, Kaempferol, and Quercetin as potential target against spike receptor protein of SARS COV

COVID-19 has been categorized as a pandemic in early 2020 and is known to cause by Severe Acute Respiratory Syndrome Coronavirus (SARS–CoV2). Numerous investigators and people in the scientific community are trying to find a superlative way to avert and cure the ailment by using phytochemicals. Abundant studies have revealed that flavonoids can be very operative in averting virus-mediated infection. The purpose of this study was to accomplish molecular docking studies among plant-derived flavonoids (Apigenin, Kaempferol, and Quercetin) and spike receptor (PDB ID: 2AJF) protein of coronavirus. Pyrx virtual screening tool and biovia discovery studio visualizer were utilized in the current molecular docking investigations. Outcomes of docking studies exposed that selected phytochemicals have interacted with targeted spike receptor protein with binding energies in the range of -6.3 to -7.3 kcal. In conclusion among the various selected ligands, quercetin may be a better inhibitor for the deactivation of SARS-Coronavirus

Prominent Classes of Antibiotics and their Mechanism of Resistance against Methicillin-Resistant Staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA) is a prominent pathogenic, antibiotic-resistant microorganism that contains a variety of virulent characteristics having the capacity to develop tolerance to several major classes of antibiotics. The ongoing creation of clones enhances this potential, transforming S. aureus into an “Anti-Infective.” MRSA has started to rise as a Hospital-Acquired MRSA, but due to evolution, new strains of MRSA have been discovered throughout the past several years. The new strains of MRSA as Community-Acquired MRSA, and Livestock-Associated MRSA are infecting the patients despite preexisting medical conditions, being as susceptible to any treatment. The continuous expansion of MRSA is still ongoing. The main goal of this article is to improve reading comprehension of MRSA by studying the prominent classes of antibiotics and their mechanism of resistance which are now susceptible or getting susceptible to the MRSA

In silico targeting of osmoporin protein of Salmonella to identify anti-Salmonellosis phyto-compounds

Salmonella enterica serotype typhi is a gram-negative, rod-shaped bacterium, and has flagella with the human body as its only reservoir. Typhoid fever was found to cause 21.7 million illnesses and 216,000 fatalities worldwide in 2000, and the International Vaccine Institute estimated 11.9 million cases and 129,000 deaths in low- and middle-income countries in 2010. More than 10 million patients were infected with S. typhi each year and the mortality rate is associated with more than 0.1 million patients. Moreover, it is also associated with drug resistance globally which makes the disease more dreadful. Other than antibiotics, various flavonoids showed medicinal effects against many diseases including S. typhi infection. Flavonoids are a type of plant bioactive metabolite that have potential medicinal efficacy. The goal of this study was to see if certain flavonoids (ellagic acid, eriodictyol, and naringenin) could interact with the outer membrane of osmoporin (PDB ID: 3uu2) receptor in Salmonella and helps in inhibiting its growth. To look for probable ligand-receptor binding relationships, we used Pyrxmolecular docking software. The molecular docking results were analyzed using the Biovia discovery studio visualizer. The current study discovered that selected plant-based compounds interacted with an outer membrane of the osmoporin receptor, resulting in minimization of energy in the range of-6.6 to -7.8 Kcal/mol

In Silico Targeting of influenza virus haemagglutinin receptor protein using Diosmetin, Tangeritin, and Anthocyanidins as potential drugs

Influenza viruses cause acute respiratory illnesses in birds, humans, and other mammals, and are a major public health concern around the world. Pandemic flu could be caused by an unforeseen human adaptation of an influenza subtype or strain rather than currently circulating influenza viruses. The need for plant metabolites-based new anti-influenza drugs appears to be urgent. Blocking Haemeagglutinin (HA) protein is one of the most appealing drug targets to halt the growth of the virus. The influenza virus can acquire resistance to currently existing therapies, therefore necessitating the development of new medications. The plant's bioactive metabolites, flavanoids are having potential medicinal efficacy. The current study aimed to identify certain flavonoids (Diosmetin, Tangeritin, and Anthocyanidins) that might interact with the HA protein of the influenza virus and help in inhibiting its growth. We used PyRx v0.8 for virtual screening and docking studies. The highest binding affinity docked structures were analyzed using PyMOL and Discovery Studio Visualizer. The present study revealed that these naturally occurring compounds interacted with HA protein, resulting in the minimization of energy in the range of -5.2 to -7.0 kcal/mol. Diosmetin showed the best binding affinity of -7.0Kcal/mol. The molecular binding studies revealed that Diosmetin, Tangeritin, and Anthocyanidins are potential compounds to test against HA protein and can be used to develop effective anti-influenza agents

RUFY1 binds Arl8b and mediates endosome-to-TGN CI-M6PR retrieval for cargo sorting to lysosomes

Arl8b, an Arf-like GTP-binding protein, regulates cargo trafficking and positioning of lysosomes. However, it is unknown whether Arl8b regulates lysosomal cargo sorting. Here, we report that Arl8b binds to the Rab4 and Rab14 interaction partner, RUN and FYVE domain-containing protein (RUFY) 1, a known regulator of cargo sorting from recycling endosomes. Arl8b determines RUFY1 endosomal localization through regulating its interaction with Rab14. RUFY1 depletion led to a delay in CI-M6PR retrieval from endosomes to the TGN, resulting in impaired delivery of newly synthesized hydrolases to lysosomes. We identified the dynein-dynactin complex as an RUFY1 interaction partner, and similar to a subset of activating dynein adaptors, the coiled-coil region of RUFY1 was required for interaction with dynein and the ability to mediate dynein-dependent organelle clustering. Our findings suggest that Arl8b and RUFY1 play a novel role on recycling endosomes, from where this machinery regulates endosomes to TGN retrieval of CI-M6PR and, consequently, lysosomal cargo sorting

The Impact of Brand Quality on Shareholder Wealth

This study examines the impact of brand quality on three components of shareholder wealth: stock returns, systematic risk, and idiosyncratic risk. The study finds that brand quality enhances shareholder wealth insofar as unanticipated changes in brand quality are positively associated with stock returns and negatively related to changes in idiosyncratic risk. However, unanticipated changes in brand quality can also erode shareholder wealth because they have a positive association with changes in systematic risk. The study introduces a contingency theory view to the marketing-finance interface by analyzing the moderating role of two factors that are widely followed by investors. The results show an unanticipated increase (decrease) in current-period earnings enhances (depletes) the positive impact of unanticipated changes in brand quality on stock returns and mitigates (enhances) their deleterious effects on changes in systematic risk. Similarly, brand quality is more valuable for firms facing increasing competition (i.e., unanticipated decreases in industry concentration). The results are robust to endogeneity concerns and across alternative models. The authors conclude by discussing the nuanced implications of their findings for shareholder wealth, reporting brand quality to investors, and its use in employee evaluation