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The redox property of iron makes it an essential cofactor for numerous enzymes involved in various metabolic processes. In vertebrates, iron is attached to either heme molecules or with other circulatory proteins, making its accessibility restricted for bacterial pathogens residing inside the host. Due to this importance, there is always an ongoing battle between the host system and pathogens, known as nutritional immunity. To capture the bound iron from the human hosts, intracellular pathogens like Mycobacterium tuberculosis secrete siderophore molecules which are ultimately uptaken by versatile transport machinery such as ATP-binding cassette (ABC) transporters. Earlier reports have suggested the presence of a heme uptake protein MhuP (ORF id: Rv0265c) in M. tuberculosis, which transiently transfers the bound iron to the protein DppA for further heme transport by utilizing its cognate transport machinery (DppBCD). In the present study, we report the crystal structure of MhuP. The binding experiments of heme with MhuP suggest its specific nature. Molecular docking studies confirm the binding of the protein MhuP with heme as well as to the protein DppA. Thus, the results indicate the binding of heme to MhuP and its probable transient transport via the DppABCD transport system in M. tuberculosis., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The use of metal-organic frameworks (MOFs) comprising custom-designed linkers/ligands as efficient and recyclable heterogeneous catalysts is on the rise. However, the topologically driven bifunctional porous MOFs for showcasing a synergistic effect of two distinct activation pathways of substrates (e.g., involving hydrogen bonding and a Lewis acid) in multicomponent organic transformations are very challenging. In particular, the novelty of such studies lies in the proper pore and/or surface engineering in MOFs for bringing the substrates in close proximity to understand the mechanistic aspects at the molecular level. This work represents the topological design, solid-state structural characterization, and catalytic behavior of an oxadiazole tetracarboxylate-based microporous three-dimensional (3D) metal-organic framework (MOF), {[Zn 2 (oxdia)(4,4'-bpy) 2 ]·8.5H 2 O} n ( 1 ), where the tetrapodal (4-connected) 5,5'-(1,3,4-oxadiazole-2,5-diyl)diisophthalate (oxdia 4- ), the tetrahedral metal vertex (Zn(II)), and a 2-connected pillar linker 4,4'-bipyridine (4,4'-bpy) are unique in their roles for the formation, stability, and function. As a proof of concept, the efficient utilization of both the oxadiazole moiety with an ability to provide H-bond acceptors and the coordinatively unsaturated Zn(II) centers in 1 is demonstrated for the catalytic process of the one-pot multicomponent Biginelli reaction under mild conditions and without a solvent. The key steps of substrate binding with the oxadiazole moiety are ascertained by a fluorescence experiment, demonstrating a decrease or increase in the emission intensity upon interaction with the substrates. Furthermore, the inherent polarizability of the oxadiazole moiety is exploited for CO 2 capture and its size-selective chemical fixation to cyclic carbonates at room temperature and under solvent-free conditions. For both catalytic processes, the chemical stability, structural integrity, heterogeneity, versatility in terms of substrate scope, and mechanistic insights are discussed. Interestingly, the first catalytic process occurs on the surface, while the second reaction occurs inside the pore. This study opens new ways to catalyze different organic transformation reactions by utilizing this docking strategy to bring the multiple components close together by a microporous MOF.

The COVID-19 pandemic and public health response to the pandemic has caused huge setbacks in the management of other infectious diseases. In the present study, we aimed to (i) assess the trends in numbers of samples from patients with influenza-like illness and severe acute respiratory syndrome tested for influenza and the number and proportion of cases detected from 2015−2021 and (ii) examine if there were changes during the COVID-19 period (2020−2021) compared to the pre-COVID-19 period (2015−2019) in three states of India. The median (IQR) number of samples tested per month during the pre-COVID-19 period was 653 (395−1245), compared to 27 (11−98) during the COVID-19 period (p value < 0.001). The median (IQR) number of influenza cases detected per month during the pre-COVID-19 period was 190 (113−372), compared to 29 (27−30) during the COVID-19 period (p value < 0.001). Interrupted time series analysis (adjusting for seasonality and testing charges) confirmed a significant reduction in the total number of samples tested and influenza cases detected during the COVID-19 period. However, there was no change in the influenza positivity rate between pre-COVID-19 (29%) and COVID-19 (30%) period. These findings suggest that COVID-19-related disruptions, poor health-seeking behavior, and overburdened health systems might have led to a reduction in reported influenza cases rather than a true reduction in disease transmission.

Ru(II)-catalyzed strategies were developed for the [4 + 1] and [4 + 2] oxidative coupling between N -aryl-2,3-dihydrophthalazine-1,4-diones and 1,4-benzoquinones, achieving spiro-indazolones and fused-cinnolines, respectively. Mild, aerobic and external oxidant-free conditions, as well as the use of a ruthenium catalyst for such (spiro)annulative strategies with quinones over reported Rh/Ir-catalyts, underline the rewards of the disclosed protocols.

WHO recommends surveillance for COVID-19 among travelers at Points of Entry (POE) to countries. At 13 selected POE at the Nepal-India border, between March 2021 and July 2021, we describe the screening, testing, diagnosis and isolation practices of COVID-19 amongst travelers. Those who stayed in India or elsewhere for > one day and those who did not have a negative RT-PCR result within the last 72 h of travel were tested for COVID-19 with rapid antigen diagnostic tests. Daily surveillance reports maintained at POE were used for analysis. Of 337,338 travelers screened, 69,886 (21%) were tested and 3907 (6%) were diagnosed with COVID-19. The proportions tested averaged 15% during April-May when screened numbers were high and increased to 35% in July when screened numbers had decreased. The proportions diagnosed positive peaked at 10% in April-May, but decreased to below 1% in June and July. Testing coverage varied from 0−99% in the different POE. Most COVID-19 cases were Nepalese, male, <60 years of age, migrant workers and presented with fever. Of COVID-19 cases, 32% had home-based isolation, 64% underwent community-based isolation and the remainder either went to hospital or returned to India. In conclusion, about one fifth of travelers overall were tested, with coverage varying considerably over time and among different POE. Strengthening surveillance processes at POE is needed.

In Nepal, case investigation and contact tracing (CICT) was adopted as an important public health measure to reduce COVID-19 transmission. In this study, we assessed the performance of CICT in Madhesh Province of Nepal against national benchmarks, using routine programmatic data reported by district CICT teams. Between May and July 2021, 17,943 COVID-19 cases were declared in the province, among which case investigation was performed for 30% (95% CI: 29.6-31.0%) within 24 h (against 80% benchmark). As a result of case investigations, 6067 contacts were identified (3 contacts per 10 cases), of which 40% were traced and tested for SARS-CoV-2 infection (against 100% benchmark). About 60% of the contacts tested positive. At most 14% (95% CI: 13.1% to 14.9%) of traced contacts underwent a 14-day follow-up assessment (against 100% benchmark). We found the performance of the CICT program in Madhesh Province to be sub-optimal and call for corrective measures to strengthen CICT in the province and the country at large. Similar studies with wider geographical scope and longer time frames are needed to identify and address deficiencies in data recording and reporting systems for COVID-19, in low- and middle-income countries like Nepal and others.

Livestock is the main backbone of the rural economy of an agriculture-based country like India. To mitigate the economic loss due to livestock's poor performance and illness, folk phytotherapy for livestock healthcare is still actively practiced in India. Literature survey revealed that the laterite region of eastern India, characterized by its cultural, ethnic, and biological diversities, as well as topographical uniqueness, lacks comprehensive information on ethnoveterinary medicinal knowledge. The objective of the present study includes documentation of traditional knowledge of ethnoveterinary medicine (EVM) from the northern laterite region in eastern India. Ethnoveterinary medicinal data were collected using a semi-structured questionnaire, free listing, and focus group discussions. The factor for informants' consensus (Fic), fidelity level (FL), and cultural value (CV) index have been employed for quantitative analyses. Jaccard index (JI) was used to check the knowledge similarity. Altogether, 1,234 citations were made by 132 participants. In total, 232 recorded ethnomedicinal species are used for preparing 306 remedies to treat 79 health disorders of livestock. Recorded species are distributed in 92 families, and Fabaceae is identified as the most medicinally diversified. Uses of 24 angiospermic taxa, one pteridophyte, and two fungal species were exclusively new to the existing inventory of Indian traditional ethnoveterinary medicine. In 20 disease categories, the informant consensus (Fic) value ranges from 0.4 to 0.83. According to the FL value and use-mention factor, 23 EVM plants have been identified as the most important species in the respective disease categories. Value of CV index highlighted nine species as culturally most significant (CV ≥ 0.0025 and frequency of citation ≥20) in the laterite region of eastern India. A large extent of recorded data are quite worthy for the Indian folk veterinary medicinal repository. A handful of new data reported here and statistically justified culturally most significant species will provide the golden opportunity for bioprospecting research., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Mandal and Rahaman.)

Diatoms are the most abundant photosynthetic microalgae found in all aquatic habitats. In the extant study, the spent biomass (after lipid extraction) of the centric marine diatom Thalassiosira lundiana CSIRCSMCRI 001 was subjected to acid digestion for the extraction of micro composite inorganic biosilica. Then, the resulting three-dimensional mesoporous biosilica material (diatomite) was used as a filler in polysulfone (PSF) membrane preparation by phase inversion. The fabricated PSF/diatomite composite membranes were characterized by SEM-EDX, TGA, and ATR-IR, and their performances were evaluated. The number of pores and pore size were increased on the membrane surface with increased diatomite in the composite membranes as compared to the control. The diatomite composite membranes had high hydrophilicity and thermal stability, lower surface roughness, and excellent water permeability. Membranes with high % diatomite, i.e., PSF/Dia 0.5 , had a maximum water flux of 806.8 LMH (Liter/m 2 /h) at 20 psi operating pressure. High-diatomite content membranes also exhibited the highest rejection of BSA protein (98.5%) and rhodamine 6G (94.8%). Similarly, in biomedical rejection tests, the PSF/Dia 0.5 membrane exhibited a maximum rejection of ampicillin (75.84%) and neomycin (85.88%) at 20 Psi pressure. In conclusion, the mesoporous inorganic biosilica material was extracted from spent biomass of diatom and successfully used in filtration techniques. The results of this study could enhance the application of natural biogenic porous silica materials in wastewater treatment for water recycling.

Introduction: Upper gastrointestinal bleeding is a common medical emergency with significant morbidity and mortality. Its causes can be classified under variceal bleeding or non-variceal bleeding. Peptic ulcer and variceal bleeding are common causes. Thus, this study aims to find the prevalence of upper gastrointestinal bleeding among patients attending the Department of Emergency in a tertiary care centre., Methods: This was a descriptive cross-sectional study conducted on patients admitted to the Department of Emergency a tertiary care centre from September 2020 to August 2021 among 3375 patients. The ethical approval was obtained from the Institutional Review Committee of the hospital (Reference number: 328). Patients presenting with the clinical features of upper gastrointestinal bleeding in the form of hematemesis or melena were enrolled after written informed consent. Data entry was done in Statistical Packages for the Social Sciences version 20.0. for descriptive analysis. Point estimate at 95% Confidence Interval was calculated along with frequency and percentage for binary data., Results: Out of 3375 admissions in the Department of Emergency, 85 (2.52%) (1.99-3.05 at 95% Confidence Interval) patients presented with upper gastrointestinal bleeding., Conclusions: The prevalence of upper gastrointestinal bleeding is lower in comparison to other studies done in similar settings., Keywords: bleeding; emergency medicine; upper gastrointestinal tract; varices.

Metal-organic framework (MOF)-based sensors for the detection of various analyte molecules has been a subject of absolute importance. However, most of these sensors rely on the turn-off (quenching) transduction response, while those reporting turn-on response are very rare. In this article, we have synthesized two new MOF-based sensors, {[Zn 2 (oxdz) 2 (tpbn)]·14H 2 O} n ( 1 ) and {[Zn 2 (oxdz) 2 (tpxn)]·10H 2 O·2C 2 H 5 OH} n ( 2 ), via the self-assembly of Zn(II) metal ions, a fluorogenic oxdz 2- linker, and bis(tridentate) ligands (tpbn and tpxn) under ambient conditions. Their formation from such a self-assembly process has been evaluated on the basis of the geometry around the five-coordinated Zn(II), preferential meridional binding of the bis(tridentate) ligands, and diverse binding of the carboxylate groups in oxdz 2- . Although 1 and 2 are isostructural, a difference in the transduction mechanism for the sensing of acetylacetone in organic solvents (turn-on for 1 and turn-off for 2 ) is observed and can be attributed to the spacer in the bis(tridentate) ligands. We have demonstrated the competing effect of the nonradiative interactions and photoinduced electron transfer toward the sensing mechanism. The results are well-supported by the Fourier transform infrared spectroscopy study, intensity versus concentration plots, spectral overlap measurements, time-resolved fluorescence studies, and MM2 and density functional theory calculations. Furthermore, we have showcased the utilization of 1 for the sensing of trace amounts of water in organic solvents.

A tender-hearted Pd(II)-catalyzed C-H activation of 1-arylindazolones followed by an oxidative [4 + 2] annulation reaction has been accomplished, engaging allenoates as annulating partners. Using this strategy, two different regioisomeric forms of cinnoline-fused indazolones possessing internal and exocyclic double bonds were synthesized in acetic acid and dioxane, respectively. Mild and aerobic conditions, avoiding the use of any metal-oxidant, highlights the rewards of this oxidative annulation protocol.

Bicyclic (alkyl)(amino)carbene (BICAAC) is introduced as a metal-free catalyst for the reduction of various nitriles to the corresponding amine hydrochloride salts in the presence of pinacolborane. Mechanistic investigations combining experiments and DFT calculations suggest a B-H addition to the carbene center, which acts as a carrier of the hydride source.

We have designed and synthesized two unprecedented microporous three-dimensional metal-organic frameworks, {[Cd 6 (TPOM) 3 (L) 6 ]·12DMF·3H 2 O} n ( 1 ) and {[Zn 2 (TPOM)(L) 2 ]·2DMF·H 2 O} n ( 2 ), based on a flexible quadritopic ligand, tetrakis(4-pyridyloxymethylene)methane (TPOM), and a bent dicarboxylic acid, 4,4'-(dimethylsilanediyl)bis-benzoic acid (H 2 L). The networks of 1 and 2 share a 4-c uninodal net NbO topology but exhibit different metal environments due to coordination preferences of Cd(II) and Zn(II). The Cd(II) center in 1 is six-coordinated, whereas the Zn(II) center in 2 is only four-coordinated, making the latter an unsaturated metal center. Such modulation of coordination atmosphere of metal centers in MOFs with the same topology is possible due to diverse binding of the carboxylate groups of L 2- . Both 1 and 2 have relatively high thermal stability and exhibit permanent porosity after the removal of guest solvent molecules based on variable temperature powder X-ray diffraction and gas adsorption analysis. These materials exhibit similar gas adsorption properties, especially highly selective CO 2 uptake/capture over other gases (N 2 and CH 4 ). However, because of the presence of an unsaturated Lewis acidic metal site, 2 acts as a very efficient heterogeneous catalyst toward the chemical conversion of CO 2 to cyclic carbonates under mild conditions, whereas 1 shows very less activity. This work provides experimental evidence for the postulate that an unsaturated metal site in MOFs enhances adsoprtion of CO 2 and promotes its conversion via the Lewis-acid catalysis.

Vitex, the genus of the family Lamiaceae, comprises of about 230 species mostly distributed in the warm regions of Europe and temperate regions of Asia. Several Vitex species have been used as folk medicine in different countries for the treatment of various kinds of diseases and ailments. The main aim of this review is to collect and analyze the scientific information available about the Vitex species regarding their chemical constituents and pharmacological activities. The phytochemical investigation of various Vitex species has resulted in the isolation of about 556 chemical constituents belong to various chemical category viz. iridoids, diterpenoids, triterpenoids, flavonoids, lignans, sesquiterpenoids, monoterpenoids, ecdysteroids, and others. The crude extracts of different Vitex species as well as pure phytochemicals exhibited a wide spectrum of in-vitro and in-vivo pharmacological activities. In the present review, the scientific literature data on the ethnopharmacological, phytochemical, and pharmacological investigations on the genus Vitex are summarized. More attention should be given in future research to evaluate the pharmacological potential with detailed mechanism of actions for the pure compounds, extracts of plants from this genus. Moreover, their clinical study is needed to justify their use in modern medicine and to further exploring this genus for new drug discovery., (© 2021 John Wiley & Sons Ltd.)

Background: B cells contribute significantly to the pathogenesis of primary Sjögren's syndrome (pSS). Free light chains (FLCs) are generated during the production of immunoglobulins (Igs) and are surrogates of B cell activity. We hypothesized that salivary FLCs and salivary Igs could represent salivary gland inflammation and therefore, serve as biomarkers in pSS., Methods: Patients >18 years old fulfilling the American College of Rheumatology / European League Against Rheumatism (EULAR) 2016 criteria for pSS and age-matched healthy and disease controls (sicca non-pSS, rheumatoid arthritis, systemic lupus erythematosus) were recruited for this cross-sectional study. FLCs in saliva and serum were measured by immunoturbidimetry. Serum and salivary Igs were measured by nephelometry and enzyme-linked immunosorbent assay, respectively. Area under the receiver operator characteristic curve was determined. The factors influencing the serum and salivary FLCs in pSS were determined using backward linear regression., Results: A total of 78 patients with pSS, 76 healthy controls and 62 disease controls were recruited. Median EULAR SS disease activity index (interquartile range) was 1 (3.75). Serum FLCκ and FLCλ, salivary FLCλ, serum and salivary IgG, salivary IgM was significantly higher in the pSS group compared to the controls. Areas under the curve for salivary FLCλ, serum FLCκ, serum and salivary IgG were 0.75, 0.72, 0.78 and 0.77, respectively. Regression analysis showed that salivary FLCκ, salivary FLCλ and salivary IgG were associated with positive salivary gland histopathology. Use of immunosuppressants and glucocorticoids was associated with lower values of salivary parameters., Conclusion: Salivary FLCλ and salivary IgG were significantly different between pSS and control groups and could be potential non-invasive biomarkers in pSS. These findings should be confirmed in larger longitudinal studies., (© 2021 Asia Pacific League of Associations for Rheumatology and John Wiley & Sons Australia, Ltd.)

Oxidative stress (OS) and reactive oxygen species (ROS) are one of the main reasons for the multifactorial concern - male infertility. ROS are active components of cellular metabolism that are intrinsic to cellular functioning and are present at minimal and unreactive levels in normal cells. They are an integral component of the sperm developmental physiology, capacitation, and function. As said "anything in excess is poison," so is the case with ROS. These, when produced in excess to the antioxidants present in the seminal plasma, cause multiple malformations during the process of spermatogenesis such as lipid peroxidation, interfere with capacitation, sperm DNA fragmentation and damage to the membrane of the sperm which in turn reduces the motility of the sperm and its ability to fuse with the oocyte. Exposure of spermatozoa to oxidative stress is a major causative agent of male infertility. Thus, a delicate balance between the beneficial and detrimental effects of ROS for proper functions is of utter importance. In this chapter, the influence of ROS in OS which is a key player in male infertility along with the diagnosis, available treatment, and prevention of extensive ROS buildup within the spermatozoa are highlighted., (© 2022. The Author(s), under exclusive license to Springer Nature Switzerland AG.)

Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases known to degrade extracellular matrix (ECM). Being involved in many biological and physiological processes of tissue remodeling, MMPs play a crucial role in many pathological conditions such as arthritis, cancer, cardiovascular diseases, etc. Typically, MMPs possess a propeptide, a zinc-containing catalytic domain, a hinge region and a hemopexin domain. Based on their structural domain organization and substrates, MMPs are classified into six different classes, viz. collagenases, stromelysins, gelatinases, matrilysins, membrane-type and other MMPs. As per previous studies, a set of invariant water (IW) molecules of MMP-1 (a collagenase) play a significant role in stabilizing their catalytic domain. However, a functional role of IW molecule in other classes of MMPs has not been reported yet. Thus, in this study, IW molecules of MMPs from different classes were located and their plausible role(s) have been assigned. The results suggest that IW molecules anchor the structurally and functionally essential metal ions present in the vicinity of the active site of MMPs. Further, they (in)directly interlink different structural features and bridge the active site metal ions of MMPs. This study provides the key IW molecules that are structurally and functionally relevant to MMPs and hence, in turn, might facilitate the development of potent generalized inhibitor(s) against different classes of MMPs. Communicated by Ramaswamy H. Sarma.

Background: A key public health priority during the emergence of a novel pathogen is probing the factors contributing in clinical severity of the disease COVID-19. Moreover, analysis of the determined clinical outcomes is required and thus, modifiable predictor values need to identified. In Ayurveda, outcome of a disease is a multivariate function and this exploratory work is an attempt to identify one such factor " Vyadhiksamatwa " (immune status)., Materials and Methods: A questionnaire-based, cross-sectional study was conducted in fifty diagnosed cases of COVID-19. Study participants were subjected to a questionnaire to assess relationship between the three determinants of the disease - exposure, clinical severity, and Vyadhiksamatwa ., Results: Clinical severity was found strongly correlated with Vyadhiksmatwa with the value of Pearson Correlation - 0.740 significant at the 0.01 level (2-tailed)., Conclusion: In the determination of clinical severity of disease, there are two epidemiological factors responsible - extrinsic (exposure) and intrinsic ( Vyadhiksamatwa ). It has been observed that higher the value of Vyadhiksamatwa of an individual, lesser will be the clinical severity of the disease in that individual. Vyadhiksamatwa can alter the host response to infections., (© 2021 The Authors.)

Perishable food spoilage caused by fungi is a major cause of discomfort for food producers. Food sensory abnormalities range from aesthetic degeneration to significant aroma, color, or consistency alterations due to this spoilage. Bio-preservation is the use of natural or controlled bacteria or antimicrobials to enhance the quality and safety of food. It has the ability to harmonize and rationalize the required safety requirements with conventional preservation methods and food production safety and quality demands. Even though synthetic preservatives could fix such issues, there is indeed a significant social need for "clean label" foods. As a result, consumers are now seeking foods that are healthier, less processed, and safer. The implementation of antifungal compounds has gotten a lot of attention in recent decades. As a result, the identification and characterization of such antifungal agents has made promising advances. The present state of information on antifungal molecules, their modes of activity, connections with specific target fungi varieties, and uses in food production systems are summarized in this review.

More than one third of proteins require metal ions to accomplish their functions, making them obligatory for the growth and survival of microorganisms in varying environmental niches. In prokaryotes, besides their involvement in various cellular and physiological processes, metal ions stimulate the uptake of citrate molecules. Citrate is a source of carbon and energy and is reported to be transported by secondary transporters. In Gram-positive bacteria, citrate molecules are transported in complex with divalent metal ions, whereas in Gram-negative bacteria they are translocated by Na + /citrate symporters. In this study, the presence of a novel divalent-metal-ion-complexed citrate-uptake system that belongs to the primary active ABC transporter superfamily is reported. For uptake, the metal-ion-complexed citrate molecules are sequestered by substrate-binding proteins (SBPs) and transferred to transmembrane domains for their transport. This study reports crystal structures of an Mg 2+ -citrate-binding protein (MctA) from the Gram-negative thermophilic bacterium Thermus thermophilus HB8 in both apo and holo forms in the resolution range 1.63-2.50 Å. Despite binding various divalent metal ions, MctA possesses the coordination geometry to bind its physiological metal ion, Mg 2+ . The results also suggest an extended subclassification of cluster D SBPs, which are known to bind and transport divalent-metal-ion-complexed citrate molecules. Comparative assessment of the open and closed conformations of the wild-type and mutant MctA proteins suggests a gating mechanism of ligand entry following an `asymmetric domain movement' of the N-terminal domain for substrate binding.

Herein a Mn(I) catalyst bearing a redox-active phenalenyl (PLY) based ligand is reported for the efficient hydrosilylation of esters to alcohols using the inexpensive silane source polymethylhydrosiloxane (PMHS) under mild conditions. Mechanistic investigations suggest a strong ligand-metal cooperation where a ligand-based single electron transfer (SET) process initiates the reaction through Si-H bond activation.

Hydrogen evolution reaction (HER) by electrochemical water splitting is one of the most active areas of energy research, yet the benchmark electrocatalysts used for this reaction are based on expensive noble metals. This is a major bottleneck for their large-scale operation. Thus, development of efficient metal-free electrocatalysts is of paramount importance for sustainable and economical production of the renewable fuel hydrogen by water splitting. Covalent organic frameworks (COFs) show much promise for this application by virtue of their architectural stability, nanoporosity, abundant active sites located periodically throughout the framework, and high electronic conductivity due to extended π-delocalization. This study concerns a new COF material, C 6 -TRZ-TFP, which is synthesized by solvothermal polycondensation of 2-hydroxybenzene-1,3,5-tricarbaldehyde (TFP) and 4,4',4''-(1,3,5-triazine-2,4,6-triyl)tris[(1,1'-biphenyl)-4-amine]. C 6 -TRZ-TFP displayed excellent HER activity in electrochemical water splitting, with a very low overpotential of 200 mV and specific activity of 0.2831 mA cm -2 together with high retention of catalytic activity after a long duration of electrocatalysis in 0.5 m aqueous H 2 SO 4 . Density functional theory calculations suggest that the electron-deficient carbon sites near the π electron-donating nitrogen atoms are more active towards HER than those near the electron-withdrawing nitrogen and oxygen atoms., (© 2021 Wiley-VCH GmbH.)

Background: Vitamin C is a water-soluble antioxidant vitamin. Oxidative stress and its markers, along with inflammatory markers, are high during critical illness. Due to conflicting results of the published literature regarding the efficacy of vitamin C in critically ill patients, and especially the concerns for nephrotoxicity raised by some case reports, this meta-analysis was carried out to appraise the evidence and affirmation regarding the role of vitamin C in critically ill patients., Methods: We searched the database thoroughly to collect relevant studies that assessed intravenous vitamin C use in critically ill patients published until 25 February 2021. We included randomized controlled trials and observational studies with 20 or more critically ill patients who have received intravenous ascorbic acid (vitamin C). After screening 18,312 studies from different databases, 53 were included in our narrative synthesis, and 48 were included in the meta-analysis. We used the Covidence software for screening of the retrieved literature. Review Manager (RevMan) 5.4 was used for the pooling of data and Odds Ratios (OR) and Mean difference (MD) as measures of effects with a 95% confidence interval to assess for explanatory variables., Results: Pooling data from 33 studies for overall hospital mortality outcomes using a random-effect model showed a 19% reduction in odds of mortality among the vitamin C group (OR, 0.81; 95% CI, 0.66-0.98). Length of hospital stay (LOS), mortality at 28/30 days, ICU mortality, new-onset AKI and Renal Replacement Therapy (RRT) for AKI did not differ significantly across the two groups. Analysis of data from 30 studies reporting ICU stay disclosed 0.76 fewer ICU days in the vitamin C group than the placebo/standard of care (SOC) group (95% CI, -1.34 to -0.19). This significance for shortening ICU stay persisted even when considering RCTs only in the analysis (MD, -0.70; 95% CI, -1.39 to -0.02)., Conclusion: Treatment of critically ill patients with intravenous vitamin C was relatively safe with no significant difference in adverse renal events and decreased in-hospital mortality. The use of vitamin C showed a significant reduction in the length of ICU stays in critically ill patients.

Purpose: : To evaluate the cost, safety, surgical outcome, and efficacy of modified Cutler-Beard eyelid reconstruction utilizing a novel silicone plate as a tarsal plate replacement in the repair of 60% to 100% eyelid defects following the excision of large malignant tumors., Methods: : A prospective, noncomparative, interventional study of 30 eyes was done over 3 years. Fourteen patients were female, and 16 patients were male. In all the cases, a silicone plate, the synthetic, artificial tarsal plate, was utilized for a total or subtotal replacement of the tarsal plate. The created defect was measured in mm (length and width) and later expressed in percentage. Pre- and postoperative action of levator palpebrae superioris (LPS) was measured. Pre- and postoperative measurements of the margin-to-margin reflex distance (MRD1) were noted., Results: : Preoperative LPS action was 1.23 ± 1.35 mm, whereas postoperative LPS actions at the end of 1 week and 18 months were 11. 8 ± 0.88 mm and 13.53 ± 0. 73 mm, respectively. Preoperative MRD1 was - 3.0 ± 1.144 mm, whereas postoperative MRD1 values at the end of 1 week and 18 months were 2.18 ± 0.27 mm and 4.16 mm ± 0.35, respectively. The mean created defect after the removal of the tumor was 87.3% ±11.10. The mean length of the silicone plate implanted in this study was 27.53 ± 2.48 mm. The follow-up period for the study participants was 18 months., Conclusion: : The synthetic novel silicone plate was successful as a tarsal plate replacement. A second surgical site for ear cartilage harvesting is avoided. Cadaver transfer of Achilles tendon carries the risk of transmission of communicable diseases, for example, hepatitis B and HIV. Silicone is an inert, nonreacting, and tissue-tested material, thus eliminating the possibility of graft rejection. This material is readily available and cost-effective. The novel silicone plate is considered to be the most promising alternative material as a tarsal replacement in the future generation., Competing Interests: None

Aim: To evaluate the efficacy and usefulness of Tenzel rotational flap in upper and lower lid reconstruction in malignant tumors, to determine the anatomical alignment, functional, and cosmetic outcome after lid reconstruction and recurrence of the tumor and to observe the canthal and fornix status. Methods: Prospective, non-comparative,interventional clinical study of 30 patients over a period of 18 months. The study was conducted with strict inclusion and exclusion criteria. Evaluation parameters were LPS (Levator palpebrae superioris) action Pre and post operative, MRD-1 (Margin Reflex Distance-1) values pre and post operative, central vertical palpebral fissure height (PFH) pre and post operative,and the calculation of the created defect express in percentage preoperatively. None of the case posterior lamina was repaired. It formed or strengthened automatically. Results: The diagnosis of Sebaceous cell carcinoma was 14/30 by FNAC and 17/30 by histopathology. The mean MRD-1 pre-operatively was -1.09 ± 1.54 mm to 4.02 ± 0.36 mm postoperatively in the upper lid. The mean LPS action pre-operatively was 4.35 ± 0.96 mm to 12.42 ± 1.24 mm postoperatively in the upper lid tumor. The mean pre-operative central palpebral aperture was 4.76 ± 0.88 mm and post-operative central palpebral aperture was 10.47 ± 0.88 mm in the upper lid tumor. The mean incision length was 8.16 ± 0.61 mm in upper lid and 9.27 ± 0.87 mm in lower lid Tenzel reconstruction respectively. In all the cases, posterior lamella grew normally. In addition, no strengthening procedure was required. Conclusion: This reconstructive procedure was useful to repair 40%-60% of the upper lid and 40%-70% created a defect in the lower eyelid after the removal of the malignant tumor. Histopathological diagnosis of the specimen was more accurate than FNAC. No repair of posterior lamella was made. No extra surgical procedure was needed. Thus, the surgical procedure time was markedly reduced. After the surgery, all the patients presented a good uplift of the upper lid, good closure of the eyelids, and were visually and functionally well rehabilitated. The aesthetic appearance was excellent., (© The Authors.Romanian Society of Ophthalmology.)

Introduction: Several studies have previously shown the benefit of thiamine supplementation in critically ill patients. In order to fully appraise the available data, we performed a meta-analysis of 18 published studies., Methods: A thorough systematic search was conducted. The studies enrolling critically ill patients receiving thiamine supplementation was compared with the standard of care (SOC) group. Data was analyzed using RevMan 5.4. Clinical outcomes were pooled using Odds Ratio (OR) and mean differences., Result: Eighteen studies (8 RCTs and 10 cohort studies) met the criteria for quantitative synthesis. In the analysis of RCTs, thiamine supplementation showed 42% lower odds of developing ICU delirium (OR 0.58, 95% CI, 0.34-0.98). A reduction in mortaliy was observed on performing fixed effect model analysis however, a level of statistical significance could not be reached on performing random effect model analysis (OR, 0.78; 95% CI, 0.59 to 1.04). Further sub-group analysis of 13 studies in patients with sepsis, there was no difference in mortality between the two groups (OR, 0.83; 95% CI, 0.63 to 1.09)., Conclusion: Thiamine supplementation in critically ill patients showed a reduction in the incidence of ICU delirium among RCTs. However, there was no significant benefit in terms of overall mortality, and mortality in patients with sepsis. Further, large scale randomized prospective studies are warranted to investigate the role of thiamine supplementation in critically ill patients., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing interests., (Copyright © 2021 Elsevier Inc. All rights reserved.)

For the preference in nuclear energy, one of the high-level liquid waste materials in the form of pertechnetate anion (TcO 4 - ) has become an environmental hazard due to its mobility into groundwater and soil. For its sequestration, numerous efforts have been reported in recent years. However, its selective sensing, even using its nonradioactive surrogate oxidizing perrhenate ion (ReO 4 - ), in aqueous media is very limited. To develop novel materials for such a purpose, we have designed an amino acid-functionalized bent dicarboxylic acid, 4-(((4-((carboxymethyl)carbamoyl)phenyl)amino)methyl)benzoic acid (H 2 hipamifba), for the strategic room-temperature synthesis of two isostructural and highly luminescent two-dimensional (2D) metal-organic coordination networks (MOCNs), {[Cu(hipamifba)(4,4'-azbpy)]·2CH 3 OH·2H 2 O} n ( 1 ) and {[Zn(hipamifba)(4,4'-azbpy)]·2CH 3 OH·2H 2 O} n ( 2 ), where 4,4'-azobipyridine (4,4'-azbpy) as a pillar linker imparts luminescent properties in the architectures. The single-crystal X-ray structural analysis demonstrates that 1 and 2 have pillared-bilayer 2D networks with the sq1/Shubnikov tetragonal plane net topology. These multiresponsive luminescent materials were gainfully employed for the selective sensing of ReO 4 - in water with a detection limit of 3.4 and 5.4 ppm for 1 and 2 , respectively. It is noteworthy to point out that these are the first neutral sensors for such study as the only other two sensors reported in the literature are cationic in nature. Their suitability (selectivity, stability, and recyclability) as excellent water-stable sensors was established through the competitive analyte test and a comparison of pristine and spent samples by powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM). Further, the mechanism of selective detection is explained by the time-resolved studies and density functional theory (DFT) calculations.

Mycobacterium tuberculosis, one of the major threats to mankind, requires micronutrients like metal ions for their survival and pathogenicity inside the host system. Intracellular pathogens such as M. tuberculosis have co-evolved to combat the nutritional immunity developed by the host. It has developed eminent mechanisms to sequester essential metal ions from the host system. One such prominent mechanism to scavenge metal ions to thrive in the host cell involves ATP-binding cassette (ABC) transporters, which transport metal ions (in free and/or complex forms) across the cell membrane. This study employs a high-throughput data mining analysis to identify open reading frames (ORFs) encoding metal uptake ABC transporters in M. tuberculosis H37Rv. In total, 19 ORFs resulting in seven ABC transport systems and two P-type ATPases were identified, which are potentially involved in the uptake of different metal ions. The results also suggest the existence of a subunit sharing mechanism in M. tuberculosis where the transmembrane and nucleotide binding domains are shared among different ABC transport systems indicating the import of multiple substrates via a single ABC transporter. Thus, this study reflects an overview of the repertoire of metal-specific ABC transport systems in M. tuberculosis H37Rv, providing potential therapeutic targets for the future., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Abnormal N-heterocyclic carbene (aNHC) based Ni(II) π-allyl complexes (3 and 4) were synthesized starting from a Ni(0) precursor. These complexes were characterized by NMR spectroscopy, single-crystal X-ray crystallography (4) and elemental analysis data. The underlying mechanism for the formation of Ni(II) η 3 -allyl complexes from a Ni(0) precursor on treatment with a free abnormal N-heterocyclic carbene in absence of any external additive or oxidant was unraveled. Later, complex 3 was exposed to O 2 gas under ambient pressure resulting in molecular oxygen activation to form a μ-hydroxo bridged Ni(II) dimer., (© 2021 Wiley-VCH GmbH.)

In recent years, the applications of low-valent main group compounds have gained momentum in the field of catalysis. Owing to the accessibility of two lone pairs of electrons, NHC-stabilised phosphinidenes have been found to be excellent Lewis bases; however, they cannot yet be used as catalysts. Herein, an NHC-stabilised phosphinidene, 1,3-dimethyl-2-(phenylphosphanylidene)-2,3-dihydro-1H imidazole (1), for the activation of CO 2 is reported.A closer inspection of the CO 2 activation process by DFT calculations along with intrinsic bond orbital analysis shows that phosphinidene is associated with phenylsilane through a noncovalent π-π interaction between two phenyl rings which activates the Si-H bond facilitating hydride transfer to the CO 2 molecule. Detailed DFT studies along with spectroscopic experiments were combined to understand the mechanism of CO 2 activation and its catalytic reductive functionalisation leading to the formylation of a range of chemically inert primary amides under mild reaction conditions., (© 2021 Wiley-VCH GmbH.)

A mesoionic N-heterocyclic olefin (mNHO) was introduced as a metal-free catalyst for the reductive functionalization of CO 2 leading to consecutive double N -methylation of primary amines in the presence of 9-borabicyclo[3.3.1]nonane (9-BBN). A wide range of secondary amines and primary amines were successfully methylated under mild conditions. The catalyst sustained over six successive cycles of N -methylation of secondary amines without compromising its activity, which encouraged us to check its efficacy towards double N -methylation of primary amines. Moreover, this method was utilized for the synthesis of two commercially available drug molecules. A detailed mechanistic cycle was proposed by performing a series of control reactions along with the successful characterisation of active catalytic intermediates either by single-crystal X-ray study or by NMR spectroscopic studies in association with DFT calculations., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The role of mangroves in sequestering metal and nutrients in sediment has been described in the past, but knowledge gaps still exist on storage capacity and recycling fluxes of elements in plant biomass, notably concerning their magnitude in root uptake and loss by litterfall. This study addresses the storage and transport pathways of 16 elements, classified as macro-nutrients (Ca, Mg, Na, K), micro-nutrients (Fe, Mn, Ni, Co, Cu, Cr, Zn, Mo), and potential toxicants (Al, Cd, Sn, Pb) in the world's largest mangroves, the Sundarbans. Elemental concentrations in plant organs were generally lower than in the sediment. The stock of macro and micro-nutrients in plant biomass varied from 60 to 2717 and 0.003 to 37.7 Mg ha -1 respectively, with highest values observed for Na and lowest for Cd. The Avicennia species exhibited the maximal accumulation of all elements. Translocation of major elements to different plant organs increased with increasing their concentrations in the sediment. Elemental loss via litterfall indicated that Sundarbans mangrove could act as a source, particularly of Mn, to the Bay of Bengal. Moreover, belowground uptake of the 16 elements showed 2-3 fold higher fluxes than their loss via litterfall. There was a significant retention of some trace elements (notably Mo, Cd, and Sn) in plant biomass, which might allow one to use these mangroves for phytoremediation and restoration purposes. We conclude that mangroves efficiently store and remobilize major and trace elements from the sediments by root uptake and recycle back to sediment surface via litterfall., Competing Interests: Declaration of competing interest Authors declare no conflict of interest. This manuscript presents original work that is not published or being considered for publication elsewhere, in whole or in part; and all co-authors fully participated in and accept responsibility for the work and agree to its submission., (Copyright © 2021 Elsevier B.V. All rights reserved.)

There is a paucity of data on epidemiology along with an incomplete registry of end-stage kidney disease (ESKD), nephrologist workforce, and variability among the countries of Gulf Cooperation Council (GCC). The study is an observation, descriptive study which aimed to describe current ESKD burden, nephrologist density, and kidney care infrastructure in GCC. Responses to a questionnaire-based survey obtained from representatives of the Nephrology Societies of GCC countries were analyzed. The categorical variables were compared using Chi-square test. A P = 5% was considered as significant. The mean prevalence of ESKD per million populations (pmp) was 551, highest in Oman (1000/pmp), least in Qatar (347/pmp). Predominant etiology in GCC was diabetes mellitus (DM) and hypertension (HTN) (100%, each), followed by chronic glomerulonephritis (66.7%). A transplant registry was maintained by all GCC countries. Hemodialysis (HD) (67.2%) was the most opted modality of kidney replacement therapy (KRT), followed by kidney transplantation (22%) and peritoneal dialysis (9.6%); 1.0% of patients opted for conservative management. Unplanned initiation of HD was three times more common. The access distribution among incident and prevalent HD patients respectively was (i) nontunneled central catheter (nTCC) (58.7 ± 36.6 vs. 1.5 ± 1.5), (ii) tunneled central catheter (23.5 ± 29.9 vs. 33.6 ± 10.0), and (iii) arteriovenous fistula (17.3± 14.4 vs. 57.8 ± 11.86). Death and transplantation were the reasons for dropout from HD. GCC has adequate kidney care infrastructure. There are 1686 nephrologists [range: Bahrain 9, Kingdom of Saudi Arabia (KSA) 1279]. Qatar, KSA, and Kuwait provide training in kidney biopsy; all countries except Bahrain have formal training programs for nTCC placement. ESKD prevalence is high, DM, HTN; glome-rulonephritis (GN) is the most common causes. The need for KRT is expected to rise in GCC. HD is the predominant KRT modality with a high prevalence of dialysis catheters as vascular access.

In this study, a water-miscible 'classic' ionic liquid (IL), 1-ethyl-3-methylimidazoliumacetate ([EMIM][Ac]), has been used for lipid extraction from marine diatoms Thalassiosira lundiana CSIR-CSMCRI 001 by following a non-polar solvent partition method. The composition of lipid was determined using gas chromatography-mass spectrometry (GC-MS). In total, 91.4 mg g -1 (dry wt) of lipid was produced, out of which the percentage of docosahexaenoic acids (DHA), myristic acid, palmitic acid, and arachidonic acid was 19.6%, 15.1%, 11.2%, and 10.4%, respectively. The IL-inseparable residual waste solution was directly used to generate green fluorescent carbon dots (FCDs) by constructing a colloidal solution with the help of a surface-active IL, choline dioctyl sulfosuccinate ([Cho][AOT]). The stability of colloidal FCDs was examined using FTIR, FT-NMR, and Raman spectroscopy. FCDs were extracted from the colloidal solutions via the demicellization process and characterized using HR-TEM (2 to 5 nm) and PXRD techniques. The optical properties of colloidal FCDs were measured using UV-Vis and fluorescence spectroscopy and showed a wide range of emission ( λ 460 nm to λ 590 nm ). Such FCD stabilized colloidal solutions could be effectively used in fluorescence imaging of yeast cells, thus making the biorefinery approach more sustainable., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Numerous amorphous solid dispersion (ASD) formulations of celecoxib (CEL) have been attempted for enhancing the solubility, dissolution rate, and in vivo pharmacokinetics via high drug loading, polymer combination, or by surfactant addition. However, physical stability for long-term shelf life and desired in vivo pharmacokinetics remains elusive. Therefore, newer formulation strategies are always warranted to address poor aqueous solubility and oral bioavailability with extended shelf life. The present investigation elaborates a combined strategy of amorphization and salt formation for CEL, providing the benefits of enhanced solubility, dissolution rate, in vivo pharmacokinetics, and physical stability. We generated amorphous salts solid dispersion (ASSD) formulations of CEL via an in situ acid-base reaction involving counterions (Na + and K + ) and a polymer (Soluplus) using the spray-drying technique. The generated CEL-Na and CEL-K salts were homogeneously and molecularly dispersed in the matrix of Soluplus polymer. The characterization of generated ASSDs by differential scanning calorimetry revealed a much higher glass-transition temperature ( T g ) than the pure amorphous CEL, confirming the salt formation of CEL in solid dispersions. The micro-Raman and proton nuclear magnetic resonance spectroscopy further confirmed the formation of salt at the -S═O position in the CEL molecules. CEL-Na-Soluplus ASSD exhibited a synergistic enhancement in the aqueous solubility (332.82-fold) and in vivo pharmacokinetics (9.83-fold enhancement in the blood plasma concentration) than the crystalline CEL. Furthermore, ASSD formulations were physically stable for nearly 1 year (352 days) in long-term stability studies at ambient conditions. Hence, we concluded that the ASSD is a promising strategy for CEL in improving the physicochemical properties and biopharmaceutical performance.

Prorocentrum lima (CSIRCSMCRI005) was isolated from the coastal seawater of Thonithurai, Tamil Nadu, India. Morphology of the isolate was studied using light microscopy (LM) and scanning electron microscopy (SEM) while phylogenetic analyses of the internal transcribed spacer region (ITS1-5.8s-ITS2), 18S rDNA, and large subunit (LSU) rDNA were also carried out. Growth of the isolate was studied, and okadaic acid (OA) production was examined using liquid chromatography with electrospray ionization and quadrupole time of flight mass spectroscopy (LC-ESI-Q-ToF-MS). Morphological features observed including oval cell shape with a broad middle region, narrow anterior and round posterior end, large central pyrenoid with starch sheath, smooth thecal surface, and V-shaped periflagellar area consisting of eight platelets matched with the description of the type species and those reported elsewhere. The ITS, 18S, and LSU sequence phylogenetic analysis revealed that the isolate was closely related to other strains reported from the pacific. The growth rate (μ) was 0.05 div. day -1 . P. lima CSIRCSMCRI005 produced okadaic acid and related esters. The production of free and total OA was 20.12 ± 4.77 and 22.30 fg cell -1, respectively. The findings of this study contribute useful information concerning the regional risk of diarrheic shellfish poisoning in the North East Indian Ocean and the global distribution and toxic potential of Prorocentrum lima. Further studies on the ecophysiology of this strain will be helpful. This manuscript reports the detailed morphological, phylogenetic, and toxicological characterization of this species from the Bay of Bengal and the North Indian Ocean as a whole., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

A storable bicyclic (alkyl)(amino)carbene (BICAAC) stabilized two coordinate zinc(0) complex [(BICAAC)2Zn] (2) was synthesized. DFT calculations reveal that BICAAC plays a decisive role in imparting the stability to 2. This complex activates the C(sp3)-Cl bond of trityl chloride generating the Gomberg's free radical with greater efficiency than metallic Zn powder.

Dehalogenative deuteration reactions are generally performed through metal-mediated processes. This report demonstrates a mild protocol for hydrodehalogenation and dehalogenative deuteration of aryl/heteroaryl halides (39 examples) using a reduced odd alternant hydrocarbon phenalenyl under transition metal-free conditions and has been employed successfully for the incorporation of deuterium in various biologically active compounds. The combined approach of experimental and theoretical studies revealed a single electron transfer-based mechanism.

Borrowing hydrogen from alcohols, storing it on a catalyst and subsequent transfer of the hydrogen from the catalyst to an in situ generated imine is the hallmark of a transition metal mediated catalytic N -alkylation of amines. However, such a borrowing hydrogen mechanism with a transition metal free catalytic system which stores hydrogen molecules in the catalyst backbone is yet to be established. Herein, we demonstrate that a phenalenyl ligand can imitate the role of transition metals in storing and transferring hydrogen molecules leading to borrowing hydrogen mediated alkylation of anilines by alcohols including a wide range of substrate scope. A close inspection of the mechanistic pathway by characterizing several intermediates through various spectroscopic techniques, deuterium labelling experiments, and DFT study concluded that the phenalenyl radical based backbone sequentially adds H + , H˙ and an electron through a dearomatization process which are subsequently used as reducing equivalents to the C-N double bond in a catalytic fashion., Competing Interests: There is no conflict to declare., (This journal is © The Royal Society of Chemistry.)

Air pollution due to dust emission is continuously increasing day by day in mining and allied industrial areas. Mining operations contribute a substantial amount of dust emission at the crushing, screening, and bulk material handling in loading areas. The ambient suspended dust particles create a severe nuisance to workers and local dwellers. For effective controlling of positive dust emission, an innovative automated dry fog dust suppression system (DFDSS) has been developed using hybrid nozzles, sensors, actuators, controllers, screw compressors, air receivers, pumps, motors, and water arrangement with filtration facility. The DFDSS was installed in a crushing and screening plant of an iron ore mine in India. Performance study indicted fugitive dust emission concentration values ranged from 354 to 7040 μg m -3 , which was reduced to 91-300 μg m -3 after installation of DFDSS. The reduced values were within the permissible limit of 1200 μg m -3 at a distance of 25 ± 2 m in the predominant downwind direction. The installed DFDSS added a meager addition of moisture content of 0.032% in the handling iron ore material, which was below the acceptable limit of 0.1%. The DFDSS precisely regulated fugitive dust emission from various mining activities without affecting the minerals processing performance. Thus, the DFDSS can be implemented effectively in different mining and allied industries where there is a dust emission problem., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Optimization of lead structures is crucial for drug discovery. However, the accuracy of such a prediction using the traditional molecular docking approach remains a major concern. Our study demonstrates that the employment of quantum crystallographic approach-counterpoise corrected kernel energy method (KEM-CP) can improve the accuracy by and large. We select human aldose reductase at 0.66 Å, cyclin dependent kinase 2 at 2.0 Å and estrogen receptor β at 2.7 Å resolutions with active site environment ranging from highly hydrophilic to moderate to highly hydrophobic and several of their known ligands. Overall, the use of KEM-CP alongside the GoldScore resulted superior prediction than the GoldScore alone. Unlike GoldScore, the KEM-CP approach is neither environment-specific nor structural resolution dependent, which highlights its versatility. Further, the ranking of the ligands based on the KEM-CP results correlated well with that of the experimental IC 50 values. This computationally inexpensive yet simple approach is expected to ease the process of virtual screening of potent ligands, and it would advance the drug discovery research.

A polar sulfone-appended copper(II) metal-organic framework (MOF; 1 ) has been synthesized from the dual-ligand approach comprised of tetrakis(4-pyridyloxymethylene)methane and dibenzothiophene-5,5'-dioxide-3,7-dicarboxylic acid under solvothermal conditions. This has been studied by different techniques that included single-crystal X-ray diffractometry, based on which the presence of Lewis acidic open-metal sites as well as polar sulfone groups aligned on the pore walls is identified. MOF 1 displays a high uptake of CO 2 over N 2 and CH 4 with an excellent selectivity ( S = 883) for CO 2 /N 2 (15:85) at 298 K under flue gas combustion conditions. Additionally, the presence of Lewis acidic metal centers facilitates an efficient size-selective catalytic performance at ambient conditions for the conversion of CO 2 into industrially valuable cyclic carbonates. The experimental investigations for this functional solvent-free heterogeneous catalyst are also found to be in good correlation with the computational studies provided by configurational bias Monte Carlo simulation for both CO 2 capture and its conversion.

The rapid expansion of global trade and human activities has resulted in a massive increase in wastewater pollution into the atmosphere. Suspended solids, organic and inorganic particles, dissolved solids, heavy metals, dyes, and other impurities contained in wastewater from various sources are toxic to the atmosphere and pose serious health risks to humans and animals. Coagulation-flocculation technology is commonly used in wastewater treatment to remove cell debris, colloids, and contaminants in a comfortable and effective manner. Flocculants, both organic and inorganic, have long been used in wastewater treatment. However, because of their low performance, non-biodegradability, and associated health risks, their use has been limited. The use of eco-friendly bioflocculants in wastewater treatment has become essential due to the health implications of chemical flocculants. Because of their availability, biodegradability, and protection, plant-derived coagulants/flocculants and plant-based grafted bioflocculants have recently made significant progress in wastewater treatment. This study will undoubtedly provide a clearer understanding of the current state, challenges, and solutions for bioflocculation in wastewater remediation using green materials for the sake of a cleaner climate.

One of the desired ways to improve robustness and crystallinity in the covalently linked reticular frameworks is through the incorporation of varied and key functionalities in these promising materials. In this work, we have strategically constructed a series of triazine-based amide-hydrazide linked COFs ( CON , CONN , and CONNCO ) by combining the flexible tri(4-formylphenoxy)cyanurate with semi-flexible 4-amino- N -(4-aminophenyl)benzamide, semi-flexible 4-aminobenzo-hydrazide, or flexible 4-amino- N -(4-aminobenzoyl)benzo-hydrazide linkages, respectively. The incorporation of an amide or a hydrazide functionality is the key to improving the crystallinity of the framework through strong intra- and interlayer H-bonding. The structural characterization of these COFs has been done with the help of numerous analytical methods. All three COFs exhibit good thermal and chemical stability in acid and base verified by PXRD and N 2 sorption studies. Their intra- and interlayer H-bonding control the rotation in eclipsed layers, which follows emissive nature. Their stability, linkage functionality, and wettability in water have been judiciously used in fluorescent on-off pH responsive proton scavenging. The protonation-deprotonation of the imine N and N-H bond of the amide or hydrazide linkage adorned in the pore walls of three COFs plays a vital role for such an outcome.