In vitro-in silico pharmacology and chemistry of Stercularin, isolated from Sterculia diversifolia.

Stercularin is a coumarin, isolated from the ethyl acetate fraction of stem bark and leaves of S. diversifolia. Pharmacologically it is active against cancer, diabetes, and inflammation etc. The molecule is further screened for in vitro pharmacological activities. In addition, a detailed description on its drug likeness and pharmacokinetic profile has been established to further explore its fate as a drug candidate. Stercularin exhibited antiglycation, immunomodulatory, and leishmanicidal activity in three different in vitro models. The IC50 values obtained in these three assays were 80.22 ± 0.46 mg/ml, 12.8 ± 1.6 µg/ml, and 8.32 ± 0.42 µg/ml, respectively. In case of drug likeness evaluation, Stercularin has acceptable physicochemical properties and compliant with major drug likeness descriptors i.e., Lipinski rule, Pfizer rule, GSK rule, and "golden triangle". Accepting Lipinski rule implies the oral drug development of Stercularin. Pharmacokinetically, Stercularin is permeable to Caco-2 and MDCK cell lines. 'Boiled-egg' plot suggest intestinal route of absorption, blood brain barrier nonpermeating, and not affected by p-glycoprotein. Stercularin has high plasma protein binding with low free fraction circulating in the plasma. Stercularin proved to be the substrate and/or inhibitor of CYP 450 system with a moderate half-life and clearance rate to allow flexible dosing regimen. Finally, slight risk of toxicity exists for Stercularin, but not being limiting factors of drug knock out. A nature isolated Stercularin possess pharmacological activities and is predicted to have acceptable pharmacokinetic profile. Further drug development and in vivo studies are desirable for optimization.

Identification of IL-2 inducible tyrosine kinase inhibitors by quantum mechanics and ligand based virtual screening approaches.

Interleukin-2-inducible T-cell kinase (ITK) is a crucial intracellular signaling mediator in normal and malignant T-cells and natural killer cells. Selective inhibition of ITK might be useful for treating a variety of disorders including; autoimmune, inflammatory, and neoplastic disorders. Over the past two decades, the clinical management of ITK inhibitors has progressed dramatically. So far, specific inhibitor with no off-target effects against ITK is available. Herein, we aim to discover potential virtual hits to fasten the process of drug design and development against ITK. In this regard, the key chemical characteristics of ITK inhibitors were identified using ligand-based pharmacophore modeling. The validated pharmacophore comprises one hydrogen bond donor and three hydrogen bond acceptors and was utilized as a 3D query in virtual screening using ZINC, Covalent, and in-house databases. A total of 12 hit compounds were chosen on the basis of their critical interactions with the significant amino acids of ITK. The orbital energies such as HOMO and LUMO of the hit compounds were calculated to evaluate the inhibitor's potencies. Further, molecular dynamics simulation demonstrated the stability of ITK upon binding of selected virtual hits. Binding energy using the MMGBSA method showed the potential binding affinity of all the hits with ITK. The research identifies key chemical characteristics with geometric restrictions that lead to ITK inhibition.Communicated by Ramaswamy H. Sarma.

Indole-pyridine carbonitriles: multicomponent reaction synthesis and bio-evaluation as potential hits against diabetes mellitus.

Background: Diabetes mellitus is a significant health disorder; therefore, researchers should focus on discovering new drug candidates. Methods: A series of indole-pyridine carbonitrile derivatives, 1-34, were synthesized through a one-pot multicomponent reaction and evaluated for antidiabetic and antioxidant potential. Results: In this library, 12 derivatives - 1, 2, 4, 5, 7, 8, 10-12, 14, 15 and 31 - exhibited potent inhibitory activities against α-glucosidase and α-amylase enzymes, in comparison to acarbose (IC50 = 14.50 ± 0.11 µM). Furthermore, kinetics, absorption, distribution, metabolism, excretion and toxicity and molecular docking studies were used to interpret the type of inhibition, binding energies and interactions of ligands with target enzymes. Conclusion: These results indicate that the compounds may be promising hits for controlling diabetes mellitus and its related complications.

Outreach Vector Control Worker's Knowledge, Attitude and Practices Towards Mosquito Control and Associated Diseases.

Background: Mosquito Control Programs are articulated to control Mosquito Borne Diseases and success of such programs depends on the activities of field workers, and their adherence to the standard operating procedures (SOP's) is governed by their knowledge, attitudes, and practices (KAP). Present study was intended to assess the KAP of mosquito control workers of Pakistan to get an exact depiction of prevailing situation. Methods: A cross-sectional descriptive study was conducted in March-April 2020. Questionnaire containing 30 closed and open-ended questions were administrated to participants. Knowledge and practices were evaluated using a scoring system i.e., by giving 1 point to each correct answer while attitude questions were analyzed individually and expressed in percentage for each response. Results: Total 639 workers were interviewed, mean age was 29.8 (SD ±7.87) years, majority (65.1%) was in age group of 18-30 years. Mean knowledge score was 6.96±1.28 (range 0-9) with 77.36% correct answers (P= 0.073). Mean practices score was 7.00±1.62 (range 2-9) with 77.83% appropriate answers (P< 0.001). Both knowledge and practices scores were higher for permanent employees, practices score increased with increase in job experience. Very weak positive correlation (r= 0.127) was observed between knowledge and practice scores. Conclusion: Appropriate practice correlates with better knowledge and positive attitude towards control activities. Hence, training on protection and protective measures for having a positive attitude among healthcare workers is necessary against the fight with mosquitoes.

Role of ultrasonography in evaluation of perianal fistula-A study of 200 cases.

OBJECTIVE: The purpose of this study was to evaluate the role of transrectal, transvaginal, or transperineal ultrasound (US) in evaluation of perianal fistula and to assess the possibility of its role as a first-line investigation for diagnosis and for follow-up as well as a possible substitute for magnetic resonance imaging (MRI). METHODS: This is a retrospective observational study of 200 patients. All the patients complaining of discharging wound, acute or chronic pain in the perianal region and patients suspected clinically having perianal sinus/fistula, referred for ultrasound evaluation were included in the study. Male patients were scanned by transrectal and transperineal ultrasound, and females by transrectal, transvaginal and transperineal approach. All the patients were followed up with referring surgeon till surgical cure, discharge, and follow-up. Out of total 200 patients, 47 were female and 153 were male patients. Patients were in age range from 16 to 74 years. The path, direction, extent, diameter and internal branching and openings of tracts were recorded. Presence, location and extent of any collection/abscess was also noted. RESULTS: Fistulae and sinus tracts are seen as hypo to anechoic tracts ranging from 2 to 10 mm in diameter. Air and mixed echogenic moving collection were noted in active tracts. Fibrous tracts were seen as well defined, echogenic structures. Depending on the chronicity and localization, walls of abscesses appeared ill defined or well defined. Findings of transrectal, transvaginal, and transperineal USG were confirmed with intraoperative findings in 200 cases. Out of which 148 patients were followed up clinically till tracts were closed. In 54 patients, there was recurrence that were operated again and followed up with ultrasound. In total 33 had internal collection along the tracts and in the perianal region. CONCLUSION: Transrectal, transvaginal, and perineal ultrasound together have the potential to reach the sensitivity of MRI. Ultrasound has its greatest advantage in being cheap, easily reproducible and an excellent modality for follow-up.

Cheminformatics-Based Discovery of Potential Chemical Probe Inhibitors of Omicron Spike Protein.

During the past two decades, the world has witnessed the emergence of various SARS-CoV-2 variants with distinct mutational profiles influencing the global health, economy, and clinical aspects of the COVID-19 pandemic. These variants or mutants have raised major concerns regarding the protection provided by neutralizing monoclonal antibodies and vaccination, rates of virus transmission, and/or the risk of reinfection. The newly emerged Omicron, a genetically distinct lineage of SARS-CoV-2, continues its spread in the face of rising vaccine-induced immunity while maintaining its replication fitness. Efforts have been made to improve the therapeutic interventions and the FDA has issued Emergency Use Authorization for a few monoclonal antibodies and drug treatments for COVID-19. However, the current situation of rapidly spreading Omicron and its lineages demands the need for effective therapeutic interventions to reduce the COVID-19 pandemic. Several experimental studies have indicated that the FDA-approved monoclonal antibodies are less effective than antiviral drugs against the Omicron variant. Thus, in this study, we aim to identify antiviral compounds against the Spike protein of Omicron, which binds to the human angiotensin-converting enzyme 2 (ACE2) receptor and facilitates virus invasion. Initially, docking-based virtual screening of the in-house database was performed to extract the potential hit compounds against the Spike protein. The obtained hits were optimized by DFT calculations to determine the electronic properties and molecular reactivity of the compounds. Further, MD simulation studies were carried out to evaluate the dynamics of protein-ligand interactions at an atomistic level in a time-dependent manner. Collectively, five compounds (AKS-01, AKS-02, AKS-03, AKS-04, and AKS-05) with diverse scaffolds were identified as potential hits against the Spike protein of Omicron. Our study paves the way for further in vitro and in vivo studies.

Molecular dynamics simulation of entecavir-silver nanoparticles at different biological pH.

Entecavir is a well-known antiviral drug, commonly prescribed for the treatment of hepatitis B and showed promising therapeutic effects against HBV polymerase. The replication of Hepatitis B Virus requires HBV-DNA polymerase and its natural substrate is deoxyguanosine triphosphate. Entercavir inhibit its activity by phosphorylating into its active metabolite. Furthermore, the efficiency of silver nanoparticles as an antimicrobial or antiviral agent is known for centuries. This study focused on the in-silico stability studies of silver nanoparticles of entecavir. The silver nanoparticles of entecavir synthesized by previously reported method. The stability of drug metal complex was predicted by analysis of variations in internal energies including potential energy, kinetic energy and different non-bonded energies during the simulation run of 4000 picoseconds of different molecular systems. After the simulation run it was concluded that the molecular systems of drug metal complex in aqueous solution at pH 4 showed greater instability as compared to the pH 2 and 6.9. This research gives the idea about the significance of molecular dynamics simulation technique in the field of pharmaceutical sciences for the analysis and characterization of pharmaceutical products and visualizes the effects of different environmental parameters on the structure and physicochemical properties of drug molecules.

Synthesis and Antiproliferative Activity of a New Series of Mono- and Bis(dimethylpyrazolyl)-s-triazine Derivatives Targeting EGFR/PI3K/AKT/mTOR Signaling Cascades.

Here, we synthesized a newseries of mono- and bis(dimethylpyrazolyl)-s-triazine derivatives. The synthetic methodology involved the reaction of different mono- and dihydrazinyl-s-triazine derivatives with acetylacetone in the presence of triethylamine to produce the corresponding target products in high yield and purity. The antiproliferative activity of the novel mono- and bis(dimethylpyrazolyl)-s-triazine derivatives was studied against three cancer cell lines, namely, MCF-7, HCT-116, and HepG2. N-(4-Bromophenyl)-4-(3,5-dimethyl-1H-pyrazol-1-yl)-6-morpholino-1,3,5-triazin-2-amine 4f, N-(4-chlorophenyl)-4,6-bis(3,5-dimethyl-1H-pyrazol-1-yl)-1,3,5-triazin-2-amine 5c, and 4,6-bis(3,5-dimethyl-1H-pyrazol-1-yl)-N-(4-methoxyphenyl)-1,3,5-triazin-2-amine 5d showed promising activity against these cancer cells: 4f [(IC50 = 4.53 ± 0.30 µM (MCF-7); 0.50 ± 0.080 µM (HCT-116); and 3.01 ± 0.49 µM (HepG2)]; 5d [(IC50 = 3.66 ± 0.96 µM (HCT-116); and 5.42 ± 0.82 µM (HepG2)]; and 5c [(IC50 = 2.29 ± 0.92 µM (MCF-7)]. Molecular docking studies revealed good binding affinity with the receptor targeting EGFR/PI3K/AKT/mTOR signaling cascades. Compound 4f exhibited potent EGFR inhibitory activity with an IC50 value of 61 nM compared to that of Tamoxifen (IC50 value of 69 nM), with EGFR inhibition of 83 and 84%, respectively, at a concentration of 10 µM. Interestingly, 4f showed remarkable PI3K/AKT/mTOR inhibitory activity with 0.18-, 0.27-, and 0.39-fold decrease in their concentration (reduction in controls from 6.64, 45.39, and 86.39 ng/mL to 1.24, 12.35, and 34.36 ng/mL, respectively). Hence, the synthetic 1,3,5-triazine derivative 4f exhibited promising antiproliferative activity in HCT-116 cells through apoptosis induction by targeting the EGFR and its downstream pathway.

Synthesis, column packing and liquid chromatography of molecularly imprinted polymers for the acid black 1, acid black 210, and acid Brown 703 dyes.

Molecularly imprinted polymers have been synthesized for the acid black 1, acid black 210, and acid brown 703 dyes using methacrylic acid, ethylene glycol, and azobisisobutyronitrile as the monomer, cross-linker, and initiator, respectively, in the ratio of 1 : 10 : 44 (template:monomer:cross-linker). The MIPs were used for the selective removal of their corresponding dyes. The selective nature of the MIPs towards their respective dyes was confirmed by a homemade liquid chromatography system. The resultant polymer materials were packed in a stainless steel column and checked for the separation of mixtures of dyes in liquid chromatography. The dyes complementary in structure to the imprinted cavities in the MIPs had long retention times, showing the highly selective nature of the MIPs. The pH, quantity of the MIPs, time, and concentration of the dyes were optimized for the highly efficient removal of the newly synthesized MIP adsorbents in batch adsorption studies. First-order, second-order, and intra-particle diffusion models were applied to all the three MIP-based adsorbents for their kinetic investigations towards the dyes. All the three MIPs selectively absorbed their target template molecule in the presence of four other template dyes having closely related structures with % RSD < 4% for the three batch experiments. The synthesized MIPs were characterized by FTIR, SEM imaging and liquid chromatography. FTIR results strongly confirmed the presence of hydrogen bonding interactions (600-900) between the template and the individual monomers present in the unwashed MIPs. Liquid chromatography revealed the highly selective nature of the MIPs towards their template molecules. The synthesized polymeric substances possess excellent thermal, chemical, and mechanical stability and can be reused several hundred times. The MIPs were applied in the removal of dyes from spiked water samples (river water, tap water and distilled water) where the % removal of the dyes by their corresponding MIPs was greater than 90%.

Deciphering the Impact of Mutations on the Binding Efficacy of SARS-CoV-2 Omicron and Delta Variants With Human ACE2 Receptor.

The pandemic of COVID-19, caused by SARS-CoV-2, has globally affected the human health and economy. Since the emergence of the novel coronavirus SARS-CoV-2, the life-threatening virus continues to mutate and evolve. Irrespective of acquired natural immunity and vaccine-induced immunity, the emerging multiple variants are growing exponentially, crossing the territorial barriers of the modern world. The rapid emergence of SARS-CoV-2 multiple variants challenges global researchers regarding the efficacy of available vaccines and variant transmissibility. SARS-CoV-2 surface-anchored S-protein recognizes and interacts with the host-cell ACE2, facilitating viral adherence and entrance into the cell. Understanding the interfacial interactions between the spike protein of SARS-CoV-2 variants and human ACE2 receptor is important for the design and development of antiviral therapeutics against SARS-CoV-2 emerging variants. Despite extensive research, the crucial determinants related to the molecular interactions between the spike protein of SARS-CoV-2 variants and host receptors are poorly understood. Thus, in this study, we explore the comparative interfacial binding pattern of SARS-CoV-2 spike RBD of wild type, Delta, and Omicron with the human ACE2 receptor to determine the crucial determinants at the atomistic level, using MD simulation and MM/GBSA energy calculations. Based on our findings, the substitution of Q493R, G496S, Q498R, and Y505H induced internal conformational changes in Omicron spike RBD, which leads to higher binding affinity than Delta spike RBD with the human ACE2 receptor, eventually contributing to higher transmission and infectivity. Taken together, these results could be used for the structure-based design of effective antiviral therapeutics against SARS-CoV-2 variants.

Theoretical investigation of selective ligand binding mode of galanin receptors.

The Galaninergic system consist of Galanin and its receptors, involved in neuromodulation and neurotransmission. Galanin regulate its physiologic and pathologic functions by interacting with three G-protein coupled receptors; GalR1, GalR2 and GalR3. The widespread distribution of Galanin and its receptor subtypes in central and peripheral nervous system makes them an attractive drug target for the treatment of neurological diseases. However, subtypes selective ligands paucity and little structural information related to either Galanin receptors and Galanin receptor-ligand complexes hampered the structure-based drug design. Thus computational modeling characterization strategy was utilized for Galanin receptor 3D structure prediction and subtypes ligands binding selectivity. Reported ligands with experimental activity were docked against the homology model of Galanin receptors. Further, the MD simulation and binding free energy calculation were carried out to determine the binding interactions pattern consistency and selectivity towards receptor subtype. Results of binding free energy of per residue indicate key contribution of GalR1 Phe115 and His267 in the selective binding of ligands while Tyr103, Tyr270 and His277 play major role in the selective binding of GalR3 ligands. Our study provide rationale for further in silico virtual screening of small molecules for the development of selective ligands against Galanin receptor subtypes.Communicated by Ramaswamy H. Sarma.

Arsenic contribution of poultry manure towards soils and food plants contamination and associated cancer risk in Khyber Pakhtunkhwa, Pakistan.

Exposure to high level of arsenic (As) through the ingestion of contaminated soil, dust and food plants can pose health risk to humans. This study investigates the total arsenic (As), arsenobetaine (AsB), monomethylarsenate (MMA), dimethylarsenate (DMA), arsenite (As3+) and arsenate (As5+) concentrations in poultry feed, manure, agricultural soils and food plants collected from Khyber Pakhtunkhwa Province, Pakistan. The total mean As concentrations in the edible parts of food plants ranged from 0.096 mg kg-1 to 1.25 mg kg-1 with percentile (P) values (P25-0.039, P50-0.0765, P75-0.165 1 mg kg-1 to P25-0.95, P50-1.23, P75-1.6 1 mg kg-1) and exceeded the food safety limit (0.1 mg kg-1) of Food & Agriculture Organization (FAO) and World Health Organization (WHO) in all plant species except Pisum sativum (pea) and Mentha arvensis (mint). The risk to human health was assessed through the average daily intake (ADI), hazards quotient (HQ), health risk index (HRI) and lifetime cancer risk (LTCR). The highest average daily intake of As via the ingestion of Malva neglecta (mallow, a leafy plant) was observed for adults and children. The ADI for adults and children (2.36 × 10-4 mg kg-1 day-1 and 6.33 × 10-4 mg kg-1 day-1) was about 13% and 5%, respectively, of the Bench Mark Dose Limit (BMDL0.5) of 3.00 × 10-3 mg kg-1 day-1 set by WHO. The HRI was 3 times more in the children (2.1) than the adults (0.79), posing non-cancer health risks (health risk index > 1) for children. The LTCR values were slightly higher (1.53 × 10-4) relative to USEPA and WHO limits (1 × 10-6 to 1 × 10-4) for children whereas a minimal cancer risk was observed for adults via consumption of selected food plants. The results showed that poultry manure can contaminate food plants that may lead to cancer and non-cancer risks in agricultural areas, Pakistan. Thus, it is important to minimize As concentration in poultry feed to safeguard human health and environment from adverse effects.

Effectiveness of a Self-Fitting Tool for User-Driven Fitting of Hearing Aids.

Hearing aids can be effective devices to compensate for age- or non-age-related hearing losses. Their overall adoption in the affected population is still low, especially in underdeveloped countries in the subpopulation experiencing milder hearing loss. One of the major reasons for low adoption is the need for repeated complex fitting by professional audiologists, which is often not completed for various reasons. As a result, self-fitting procedures have been appearing as an alternative. Key open questions with these digital tools are linked to their effectiveness, utilized algorithms, and achievable end-results. A digital self-fitting prototype tool with a novel quick four-step fitting workflow was evaluated in a study on 19 individuals with moderate hearing loss. The tool was evaluated in a double-blinded, randomized study, having two study aims: comparing traditional audiological fitting with the new self-fitting tool, which can also be used as a remote tool. The main reported results show moderately high usability and user satisfaction obtained during self-fitting, and quasi-equivalence of the performance of the classical audiological fitting approach. The digital self-fitting tool enables multiple sessions and easy re-fitting, with the potential to outperform the classical fitting approach.

Performance Evaluation of Soft Computing Approaches for Forecasting COVID-19 Pandemic Cases.

An unexpected outbreak of deadly Covid-19 in later part of 2019 not only endangered the economies of the world but also posed threats to the cultural, social and psychological barriers of mankind. As soon as the virus emerged, scientists and researchers from all over the world started investigating the dynamics of this disease. Despite extensive investments in research, no cure has been officially found to date. This uncertain situation rises severe threats to the survival of mankind. An ultimate need of the time is to investigate the course of disease transfer and suggest a future projection of the disease transfer to be enabled to effectively tackle the always evolving situations ahead. In the present study daily new cases of COVID-19 was predicted using different forecasting techniques; Autoregressive Integrated Moving Average (ARIMA), Exponential Smoothing/Error Trend Seasonality (ETS), Artificial Neural Network Models (ANN), Gene Expression Programming (GEP), and Long Short-Term Memory (LSTM) in four countries; Pakistan, USA, India and Brazil. The dataset of new daily confirmed cases of COVID-19 from the date on which first case was registered in the respective country to 30 November 2020 is analyzed through these five forecasting models to forecast the new daily cases up to 31st January 2020. The forecasting efficiency of each model was evaluated using well known statistical parameters R 2, RMSE, and NSE. A comparative analysis of all above-mentioned models was performed. Finally, the study concluded that Long Short-Term Memory (LSTM) neural network-based forecasting model projected the future cases of COVID-19 pandemic best in all the selected four stations. The accuracy of the model ranges from coefficient of determination value of 0.85 in Brazil to 0.96 in Pakistan. NSE value for the model in India is 0. 99, 0.98 in USA and Pakistan and 0.97 in Brazil. This high-accuracy forecast of COVID-19 cases enables the projection of possible peaks in near future in the aforementioned countries and, therefore, prove to be helpful in formulating strategies to get prepared for the potential hard times ahead.

ß-Sitosterol Alters the Inflammatory Response in CLP Rat Model of Sepsis by Modulation of NFκB Signaling.

PURPOSE: Sepsis originates from the host inflammatory response, especially to bacterial infections, and is considered one of the main causes of death in intensive care units. Various agents have been developed to inhibit mediators of the inflammatory response; one prospective agent is ß-sitosterol (ßS), a phytosterol with a structure similar to cholesterol. This study is aimed at evaluating the effects of ßS on the biomarkers of inflammation and liver function in cecal ligation and puncture- (CLP-) induced septic rats. METHODS: Thirty male Wistar rats were divided equally into six groups as follows: sham, CLP, CLP+dexamethasone (DX, 0.2 mg/kg), CLP+ßS (1 mg/kg), CLP+imipenem (IMI, 20 mg/kg), and CLP+IMI (20 mg/kg)+ßS (1 mg/kg). Serum levels of IL-1ß, IL-6, IL-10, AST, ALT, and liver glutathione (GSH) were assessed by ELISA. Liver expression levels of TNF-α and NF-κBi mRNAs were evaluated by RT-qPCR. RESULTS: Serum concentrations of IL-1ß, IL-6, IL-10, ALT, and AST and mRNA levels of TNF-α and NF-κBi were all significantly higher in septic rats than in normal rats (p < 0.05). Liver GSH content was markedly lower in the CLP group than that in the sham group. ßS-treated rats had remarkably lower levels of IL-1ß, IL-6, IL-10, TNF-α, NF-κBi, AST, and ALT (51.79%, 62.63%, 41.46%, 54.35%, 94.37%, 95.30%, 34.87%, and 46.53% lower, respectively) and greater liver GSH content (35.71% greater) compared to the CLP group (p < 0.05). CONCLUSION: ßS may play a protective role in the septic process by mitigating inflammation. This effect is at least partly mediated by inhibition of the NF-κB signaling pathway. Thus, ßS can be considered as a supplementary treatment in septic patients.

Assessment of the proposed pseudo-potential theoretical model for the static and dynamic Raman scattering intensities: Multivariate statistical approach to quantum-chemistry protocols.

Accurate calculation of molecular polarizabilities and Raman intensities required high-level correlated wave functions (CCSD) and large basis set with the inclusion of electronic correlation within experimental precision. These requirements, in terms of time and computation, are economically costly. Polarized Gaussian basis sets adapted to effective core potentials (ECPs) for the static and frequency dependent Raman intensities is presented. The results of the proposed basis sets at CCSD and DFT levels in comparison with Sadlej-pVTZ, as reference basis set, show quite a good quantitative agreement in the properties with a valuable reduction in the computational time and resources. Multivariate principal component analysis (PCA) was performed to study the assessment of the efficiency of proposed methodology and diagnose the inherent information related to the kind of normal vibrational mode of each molecule, based on the variations in the computed Raman intensities. The results, in the form of score-plots, explored a clear segregation and classification among the Raman intensities data, revealing its dependence on the excitation frequencies of laser and nature of the vibrational mode of each molecule of interest. Moreover, the projection of the loadings-plots of the PCs successfully enabled to classify the most correlated computational methods in to the same groups, and made isolations of the less efficient basis functions at the corresponding theoretical method.

Foraging behavior and bait station preference in scavenging termite, Odontotermes obesus (Blattodea: Termitidae).

Termites are a significant pest of buildings, agriculture, and trees, and are mainly controlled by baiting. However, baiting systems are available for only lower termites (Rhinotermitidae) not for higher termites (Termitidae). Termite foraging behavior associated with baiting systems varies among species and families, and plays a significant role in baiting success. Here, foraging behavior of Odontotermes obesus (Blattodea: Termitidae: Macrotermitinae), a fungus-growing higher termite, was investigated relative to three bait-station sizes (small, medium, and large) containing different quantities of food. Significantly more workers recruited to large stations (470/station) compared to medium (246/station) and small (124/station) stations. Abundance of O. obesus in large and medium stations significantly positively correlated with relative humidity whereas negative but non-significant correlations were observed with temperature in large and medium stations. Total and continuous contacts with the stations increased with time and were greater in large stations. Station abandonment due to disturbance was significantly less in large stations (3%) followed by medium (9%) and small stations (20%). Our results suggest that large stations (≈8 litres volume) work best for population management of O. obesus and other related fungus-growing higher termites.

Validation of an Enzyme-Driven Model Explaining Photosynthetic Rate Responses to Limited Nitrogen in Crop Plants.

The limited availability of nitrogen (N) is a fundamental challenge for many crop plants. We have hypothesized that the relative crop photosynthetic rate (P) is exponentially constrained by certain plant-specific enzyme activities, such as ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), NADP-glyceraldehyde-3-phosphate dehydrogenase (NADP-G3PDH), 3-phosphoglyceric acid (PGA) kinase, and chloroplast fructose-1,6-bisphosphatase (cpFBPase), in Triticum aestivum and Oryza sativa. We conducted a literature search to compile information from previous studies on C3 and C4 crop plants, to examine the photosynthetic rate responses to limited leaf [N] levels. We found that in Zea mays, NADP-malic enzyme (NADP-ME), PEP carboxykinase (PCK), and Rubisco activities were positively correlated with P. A positive correlation was also observed between both phosphoenolpyruvate carboxylase (PEPC) and Rubisco activity with leaf [N] in Sorghum bicolor. Key enzyme activities responded differently to P in C3 and C4 plants, suggesting that other factors, such as leaf [N] and the stage of leaf growth, also limited specific enzyme activities. The relationships followed the best fitting exponential relationships between key enzymes and the P rate in both C3 and C4 plants. It was found that C4 species absorbed less leaf [N] but had higher [N] assimilation rates (A rate) and higher maximum photosynthesis rates (Pmax ), i.e., they were able to utilize and invest more [N] to sustain higher carbon gains. All C3 species studied herein had higher [N] storage (Nstore) and higher absorption of [N], when compared with the C4 species. Nstore was the main [N] source used for maintaining photosynthetic capacity and leaf expansion. Of the nine C3 species assessed, rice had the greatest Pmax , thereby absorbing more leaf [N]. Elevated CO2 (eCO2) was also found to reduce the leaf [N] and Pmax in rice but enhanced the leaf [N] and N use efficiency of photosynthesis in maize. We concluded that eCO2 affects [N] allocation, which directly or indirectly affects Pmax . These results highlight the need to further study these physiological and biochemical processes, to better predict how crops will respond to eCO2 concentrations and limited [N].

Reduced graphene oxide-TiO2/sodium alginate 3-dimensional structure aerogel for enhanced photocatalytic degradation of ibuprofen and sulfamethoxazole.

In this study, graphene oxide and titanium dioxide in combination with sodium alginate were used to synthesize the reduced graphene oxide-TiO2/sodium alginate (RGOT/SA) aerogel. The potential of RGOT/SA aerogel was evaluated for the photocatalytic degradation of ibuprofen and sulfamethoxazole and was compared with that of bare titanium dioxide nanoparticles. More than 99% removal of both the contaminants was obtained within 45-90 min by using the RGOT/SA aerogel under UV-A light. Mineralization of both the pollutants was also higher in case of RGOT/SA aerogel as compared to bare TiO2 nanoparticles. The optimal mass ratio of TiO2 nanoparticles with respect to graphene oxide was 2:1 in RGOT/SA aerogel in the presence of 1 wt% sodium alginate solution. High photodegradation of Ibuprofen was observed at neutral pH and acidic to neutral pH was found suitable for the photodegradation of sulfamethoxazole. Three-dimensional interconnected macroporous assembly, large surface area for settling TiO2 nanoparticles, efficient charge partitioning, and enhanced physical and chemical adsorption of ibuprofen and sulfamethoxazole on the surface of RGOT/SA aerogel were the significant characteristics of RGOT/SA aerogels. Moreover, ease of separation and recyclability of the RGOT/SA aerogel could further save the extra energy used to separate nanoparticles from the effluent.

An non-loglinear enzyme-driven law of photosynthetic scaling in two representative crop seedlings under different water conditions.

The loglinear pattern of respiratory scaling has been studied for over a century, while an increasing number of non-loglinear patterns have been found in the plant kingdom. Several previous studies had attempted to reconcile conflicting patterns from the aspects of statistical approaches and developmental stages of the organisms. However, the underlying enzymatic mechanism was largely ignored. Here, we propose an enzyme-driven law of photosynthetic scaling and test it in typical crop seedlings under different water conditions. The results showed that the key enzyme activity, the relative photosynthetic assimilation and the relative growth rate were all constrained by the available water, and the relationship between these biological traits and the available water supported our predictions. The enzyme-driven law appears to be more suitable to explain the curvature of photosynthetic scaling than the well-established power law, since it provides insight into the biochemical origin of photosynthetic assimilation.