Chemistry of Cyclo[18]Carbon (C18): A Review.

Carbon-based allotropes are propelling a technological revolution in communication, sensing, and computing, concurrently challenging fundamental theories of the previous century. Nevertheless, the demand for advanced carbon-based materials remains substantial. The crux lies in the efficient and reliable engineering of novel carbon allotrope. Although C18 has undergone theoretical and experimental investigation for an extended period, its preparation and direct observation in the condensed phase occurred only recently through STM/AFM techniques. The distinctive cyclic ring structure and the dual 18-center π delocalization character introduce various uncommon properties to C18, rendering it a subject worthy of in-depth exploration. In this context, this review delves into past developments contributing to the state-of-the-art understanding of C18 and provides insights into how future endeavours can expedite practical applications. Encompassing a broad spectrum, this review comprehensively investigates almost all facets of C18, including geometric characteristics, electron delocalization, bonding nature, aromaticity, reactivity, electronic excitation, UV/Vis spectrum, intermolecular interaction, response to external fields, electron affinity, ionization, and other molecular properties. Moreover, the review also outlines representative strategies for the direct synthesis and characterization of C18 using atom manipulation techniques. Following this, C18-based complexes are summarized, and potential applications in catalysis, electrochemical devices, optoelectronics, and sensing are discussed.

Genome sequence of bubaline herpesvirus-1 associated with pustular vulvovaginitis in Indian water buffalo.

We report here the genome sequence of a bubaline herpesvirus 1 isolated from Indian water buffalo. The bubaline herpesvirus 1 strain S102_1 was isolated in 2021 from a Murrah buffalo heifer with clinical presentation of pustular vulvovaginitis.

Revealing the interface chemistry of polyaniline grafted biomass via statistical modeling of multi-component dye systems: optimization, kinetics, thermodynamics, and adsorption mechanism.

The growing need to examine the adsorption capabilities of innovative materials in real-world water samples has encouraged a shift from single to multicomponent adsorption systems. In this study, a novel composite, PANI-g-SM was synthesized by covalently grafting a lignocellulosic biomass, Saccharum munja (SM) with polyaniline (PANI). The as-synthesized composite was investigated for the simultaneous adsorption of cationic (Methylene Blue (MB); Crystal Violet (CV)) and anionic dyes (Reactive Red 35 (RR); Fast Green FCF (FG)) from four single components and two binary systems, MB + RR and CV + FG. Further, the effect and interaction of pH (2-11), dosage (0.01-0.04 g/10 mL), and initial concentration (0.0313 to 0.1563 mmol/L) on the elimination of dyes by PANI-g-SM were studied through a novel design of Box-Behnken of Response Surface Methodology (RSM) technique which was found to be highly useful for revealing the chemistry of interfaces in multi-component systems. The extended Langmuir model for the binary system indicated the presence of synergism, as result the maximum monolayer adsorption capacity increased by 44.44%, 645.83%, 67.88%, and 441.07% for MB, RR, CV, and FG dye, respectively. Further, the adsorption process mainly followed a pseudo-second-order kinetic model, and the thermodynamic studies revealed the exothermic nature of adsorption for RR and FG dye while endothermic for MB and CV dye, respectively with Δ G varying from - 1.68 to - 6.12 kJ/mol indicating the spontaneity of the process. Importantly, the efficacy of the composite was evaluated for the treatment of textile industry effluent highlighting its potential as an adsorbent for wastewater treatment.

Ensemble Deep Learning Derived from Transfer Learning for Classification of COVID-19 Patients on Hybrid Deep-Learning-Based Lung Segmentation: A Data Augmentation and Balancing Framework.

BACKGROUND AND MOTIVATION: Lung computed tomography (CT) techniques are high-resolution and are well adopted in the intensive care unit (ICU) for COVID-19 disease control classification. Most artificial intelligence (AI) systems do not undergo generalization and are typically overfitted. Such trained AI systems are not practical for clinical settings and therefore do not give accurate results when executed on unseen data sets. We hypothesize that ensemble deep learning (EDL) is superior to deep transfer learning (TL) in both non-augmented and augmented frameworks. METHODOLOGY: The system consists of a cascade of quality control, ResNet-UNet-based hybrid deep learning for lung segmentation, and seven models using TL-based classification followed by five types of EDL's. To prove our hypothesis, five different kinds of data combinations (DC) were designed using a combination of two multicenter cohorts-Croatia (80 COVID) and Italy (72 COVID and 30 controls)-leading to 12,000 CT slices. As part of generalization, the system was tested on unseen data and statistically tested for reliability/stability. RESULTS: Using the K5 (80:20) cross-validation protocol on the balanced and augmented dataset, the five DC datasets improved TL mean accuracy by 3.32%, 6.56%, 12.96%, 47.1%, and 2.78%, respectively. The five EDL systems showed improvements in accuracy of 2.12%, 5.78%, 6.72%, 32.05%, and 2.40%, thus validating our hypothesis. All statistical tests proved positive for reliability and stability. CONCLUSION: EDL showed superior performance to TL systems for both (a) unbalanced and unaugmented and (b) balanced and augmented datasets for both (i) seen and (ii) unseen paradigms, validating both our hypotheses.

Recent Developments in Nanotechnology-Based Biosensors for the Diagnosis of Coronavirus.

The major challenge in today's world is that medical research is facing the existence of a vast number of viruses and their mutations, which from time to time cause outbreaks. Also, the continuous and spontaneous mutations occurring in the viruses and the emergence of resistant virus strains have become serious medical hazards. So, in view of the growing number of diseases, like the recent COVID-19 pandemic that has caused the deaths of millions of people, there is a need to improve rapid and sensitive diagnostic strategies to initiate timely treatment for such conditions. In the cases like COVID-19, where a real cure due to erratic and ambiguous signs is not available, early intervention can be life-saving. In the biomedical and pharmaceutical industries, nanotechnology has evolved exponentially and can overcome multiple obstacles in the treatment and diagnosis of diseases. Nanotechnology has developed exponentially in the biomedical and pharmaceutical fields and can overcome numerous challenges in the treatment and diagnosis of diseases. At the nano stage, the molecular properties of materials such as gold, silver, carbon, silica, and polymers get altered and can be used for the creation of reliable and accurate diagnostic techniques. This review provides insight into numerous diagnostic approaches focused on nanoparticles that could have been established for quick and early detection of such diseases.

Eudragit S-100 Surface Engineered Nanostructured Lipid Carriers for Colon Targeting of 5-Fluorouracil: Optimization and In Vitro and In Vivo Characterization.

5-Fluorouracil (5-FU) is the most preferred chemotherapeutic agent in the management of colon cancer but is associated with poor therapeutic efficacy and lack of site specificity. Hence, it was aimed to employ Eudragit S100 surface engineered 5-FU nanostructured lipid carriers for the spatial and temporal release of the drug for the treatment of colon cancer. Hot high-pressure homogenization (HPH) technique was employed in the preparation of 5-FU-NLCs. The optimization of 5-FU-NLCs was performed using a Quality by Design (QbD) approach. A 32 factorial design was employed wherein the relationship between independent variables [amount of oleic acid (X1) and concentration of Tween®80 (X2)] and dependent variables [particle size (Y1) and % entrapment efficiency (Y2)] was studied. Optimized 5-FU-NLCs were surface treated to obtain Eudragit S100-coated 5-FU-NLCs (EU-5-FU-NLCs). The evaluation parameters for 5-FU-NLCs and EU-5-FU-NLCs included surface morphology, particle size, PDI, and zeta potential. In vitro release from EU-5-FU-NLCs revealed a selective and controlled 5-FU release in the colonic region for 24 h. In vitro cytotoxicity (MTT assay) was performed against Caco-2 cancer cells, wherein EU-5-FU-NLCs exhibited a 2-fold greater cytotoxic potential in comparison to a 5-FU solution (5-FU-DS). Oral administration of EU-5-FU-NLCs in Albino Wistar rats depicted a higher Cmax (2.54 folds) and AUC (11 folds) as well as prolonged Tmax (16 folds) and MRT (4.32 folds) compared to 5-FU-DS confirming higher bioavailability along with the spatial and temporal release in the colonic region. Thus, a multifaceted strategy involving abridgement of nanotechnology along with surface engineering is introduced for effective chemotherapy of colon cancer via oral administration of 5-FU with uncompromised safety and higher efficacy.Graphical abstract.

An Epidemiological Analysis of SARS-CoV-2 Genomic Sequences from Different Regions of India.

The number of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) cases is increasing in India. This study looks upon the geographic distribution of the virus clades and variants circulating in different parts of India between January and August 2020. The NPS/OPS from representative positive cases from different states and union territories in India were collected every month through the VRDLs in the country and analyzed using next-generation sequencing. Epidemiological analysis of the 689 SARS-CoV-2 clinical samples revealed GH and GR to be the predominant clades circulating in different states in India. The northern part of India largely reported the 'GH' clade, whereas the southern part reported the 'GR', with a few exceptions. These sequences also revealed the presence of single independent mutations-E484Q and N440K-from Maharashtra (first observed in March 2020) and Southern Indian States (first observed in May 2020), respectively. Furthermore, this study indicates that the SARS-CoV-2 variant (VOC, VUI, variant of high consequence and double mutant) was not observed during the early phase of virus transmission (January-August). This increased number of variations observed within a short timeframe across the globe suggests virus evolution, which can be a step towards enhanced host adaptation.

COVID-19: Asymptomatic Carrier: An Autopsy Case Report.

The severe acute respiratory syndrome (SARS)-coronavirus- 2 (CoV-2) outbreak in Wuhan, China has now spread to many countries across the world including the India with an increasing death toll. On March 11, 2020, the new clinical condition COVID-19 (Corona-Virus-Disease-19) was declared a pandemic by the World Health Organization (WHO). Owing to its infectivity, high risk of transmission, and limited handling of dead bodies, published data on the course of diseases has been limited. Most patients with COVID-19 have a mild disease course and remain as asymptomatic carrier; however, few patients of older age and with co-morbidites develop severe disease leading on to fatality. If due to COVID-19 infection death occurs, an autopsy is unlikely. However in unnatural deaths the legal duty impels the proper performance of a full autopsy, to find out the cause and manner of death. The detailed autopsy examination along with histo-pathological findings in the organs of asymptomatic patient of COVID-19 and its comparison with microscopic findings in Aluminium Phosphide poisoning are discussed below. This will summarizes the research status for COVID-19 deaths, which will be important for evaluation of cause of death, prevention, control and clinical strategies of COVID-19.

The effects of cesium lead bromide quantum dots on the performance of copper phthalocyanine-based organic field-effect transistors.

Highly luminescent all-inorganic cesium lead bromide (CsPbBr3) perovskite quantum dots (QDs) have been extensively used as a photosensitizer in optoelectronic devices, while p-type small-organic-molecule copper phthalocyanine (CuPc) is also widely used as a photoactive material in solar cells, organic field-effect transistors (OFETs), etc. In this paper, we report the preparation of a CsPbBr3-QDs/CuPc heterostructure to study the effect of CsPbBr3-QDs on CuPc. The optical properties of both CuPc and the QDs/CuPc heterostructure were compared and contrasted using UV-vis absorbance and photoluminescence (PL) measurements. Furthermore, to study their electronic and charge transfer features, we fabricated field-effect transistors (FETs) on both pristine CuPc and QDs/CuPc heterostructure thin films and studied their photoresponsive electrical characteristics. Both pristine and QDs/CuPc-based FETs showed an enhancement in current and carrier mobility under illumination. The enhancement in the current and carrier mobility of the QDs/CuPc-based FETs is due to a large number of photoexcited charge carriers. We also observed that the current and carrier mobility in the QDs/CuPc heterostructure-based FET were lower than those of the pristine CuPc-based FET. This can be explained by the n-type doping effect of CsPbBr3 QDs on CuPc, which reduces the accumulation of holes in the active p-channel near the insulating layer and causes charge to be transferred from the QDs to the CuPc. Thus, we have observed a charge transfer effect in the CsPbBr3 QDs/CuPc heterostructure, which can be used in optoelectronic devices.

Palladium-Catalyzed Imidoylation-Triggered [2 + 2 + 1] Cyclization of Internal Alkyne with Isocyanides.

In this work, a palladium-catalyzed [2 + 2 + 1] cyclization of internal alkynes with double isocyanides is described. This facile procedure is efficient for synthesizing various pyrrolo[3,2-c]quinolin-2-amines. The reaction worked well with a broad reaction scope. In the process, it is believed that sequential double isocyanide insertion, 6-exo-dig cyclization of alkyne, and addition of an imino group are involved.

An efficient low-cost xylem sap isolation method for bacterial wilt assays in tomato.

PREMISE: A portable, simple, yet efficient method was developed for the rapid extraction of xylem sap from the stems and petioles of tomato plants for diagnostic and quantification assays of the xylem-colonizing wilt bacterium Ralstonia solanacearum. METHODS AND RESULTS: Xylem saps were extracted from tomato stem sections using negative pressure generated from handheld needleless syringes. The samples were collected from plants grown under different soil moisture levels at four days after inoculation with the pathogen. Pipette tips were modified to serve as adapters for the stem sections. The quantification of the bacterial load in the extracted sap was performed by plating sap dilutions in Kelman's triphenyltetrazolium chloride (TTC) medium. Pathogen identity was further confirmed by performing a PCR using R. solanacearum-specific primers. CONCLUSIONS: Due to its simplicity, portability, and thoroughness of extraction from predetermined tissue sizes, the method can potentially facilitate high-throughput onsite sampling from a large number of samples in a short time, which cannot be achieved with other available techniques.

Synthesis of 3-Hydroxyisoindolin-1-ones through 1,4-Dioxane-Mediated Hydroxylhydrative aza-Cyclization of 2-Alkynylbenzamide in Water.

In this work, 1,4-dioxane-mediated hydroxylhydrative aza-cyclization of 2-alkynylbenzamide is developed for the synthesis of 3-hydroxylisoindolin-1-ones. The transformation proceeds smoothly in water with good yields and a broad reaction scope. Mechanistic studies show that regioselective brimonative 5-exo-dig aza-cyclization, bromohydration of the resulting alkene groups, and hydrolysis of dibromo compounds are involved. Compared to the traditional methodologies, the synthetic procedure reported herein represents a cleaner route toward 3-hydroxylisoindolin-1-ones.

Assessing the viability of Soluplus® self-assembled nanocolloids for sustained delivery of highly hydrophobic lapatinib (anticancer agent): Optimisation and in-vitro characterisation.

Nanocolloids are considered ideal carriers for hydrophobic drugs owing to their core-shell structure. Lapatinib is a potential anti-cancer agent, but its clinical use is limited because of its poor aqueous solubility, thus requiring larger oral doses with the associated toxicity. Thus, in the present study, we fabricated self-assembled nanocolloidal polymeric micelles (LP-PMs) of Soluplus® and Pluronic® F127 by the thin-film hydration method and assessed their delivery potential of the hydrophobic anti-cancer drug lapatinib (LP) and optimised these nanocolloidal polymeric micelles using Quality-by-Design approach. Amorphisation of the drug and no typical incompatibility other than hydrogen bonding in the LP-PMs was confirmed by solid-state characterisation. The LP-PMs exhibited a uniform size of 92.9 ± 4.07 nm, with a 5.06 mV zeta potential and approximately 87% drug encapsulation. The critical micellar concentration (CMC) of Soluplus® decreased from 6.63 × 10-3 to 4.4 × 10-3 mg/mL by incorporating Pluronic® F127. Further, the sustained release of LP from the LP-PMs was confirmed by in-vitro release studies showing 36% and 60% of LP released from the LP-PMs within 48 h in release media of pH 7.4 and pH 5.0, respectively. These results support their capability of preferential release at acidic tumor environment. Their hemocompatibility evidenced by hemolysis below accepted limits and no platelet aggregation with resistance to instant dilution illustrated their admirable blood compatibility and suitability for intravenous administration. The encapsulation of LP inside micelles enhanced the cytotoxicity of LP against SKBr3 breast cancer cells. Further, the LP-PMs were found to be stable over six months when stored at 2-8 °C. These findings indicate the improved potential of nanocolloidal polymeric micelles as promising carriers for the preferential and sustained delivery of hydrophobic anticancer drugs such as lapatinib to tumours.

Carrier Induced Hopping to Band Conduction in Pentacene.

Charge transport in organic thin films which are generally polycrystalline is typically limited by the localization of the carriers at lattice defects resulting in low carrier mobilities and carriers move from one state to another state by hopping. However, charge transport in organic semiconductors in their single crystalline phase is coherent due to band conduction and mobilities are not limited by disorder resulting in higher carrier mobility. So it is a challenge to enhance the carrier mobility in a thin film which is the preferred choice for all organic devices. Here, we show that it is possible to increase the carrier mobility in polycrystalline thin films by injecting sufficient carriers such that Fermi level can be moved into the region of high density in Gaussian density of states of molecular solids. When the hopping transport happens through the molecular energy levels whose density is low, mobility is decided by incoherent transport however, when the the hopping transport happens through the energy levels with high density, mobility is decided by coherent transport, as in band conduction. We present results highlighting the observation of both band-like and hopping conduction in polycrystalline organic thin films by varying the concentration of injected charge. More importantly the transition from hopping to band transport is reversible. The observed carrier mobilities in both the regimes match well with theoretical estimates of hopping mobility and band mobility determined from first principles density functional theory.

Locust bean gum and sodium alginate based interpenetrating polymeric network microbeads encapsulating Capecitabine: Improved pharmacokinetics, cytotoxicity &in vivo antitumor activity.

A combination of biopolymers sodium alginate and locust bean gum has been used to prepare an interpenetrating polymeric network of an anticancer drug Capecitabine by ionotropic gelation method. For the optimization 32 levels, a full factorial design was employed to examine the influence of independent factors, i.e. polymer ratio and cross-linker concentration on responses particle size and drug entrapment. The obtained optimized formulation was examined for solid-state characterization, swelling study, in vitro drug release, SRB study, oral toxicity study, in vivo pharmacokinetic and in vivo antitumor study. The results of all the studies performed were found suitable in extending the release of a short elimination half-life drug with improved bioavailability and suggesting it to be safe and effective for oral drug delivery in treating colon cancer.

Contrasting selective patterns across the segmented genome of bluetongue virus in a global reassortment hotspot.

For segmented viruses, rapid genomic and phenotypic changes can occur through the process of reassortment, whereby co-infecting strains exchange entire segments creating novel progeny virus genotypes. However, for many viruses with segmented genomes, this process and its effect on transmission dynamics remain poorly understood. Here, we assessed the consequences of reassortment for selection on viral diversity through time using bluetongue virus (BTV), a segmented arbovirus that is the causative agent of a major disease of ruminants. We analysed ninety-two BTV genomes isolated across four decades from India, where BTV diversity, and thus opportunities for reassortment, are among the highest in the world. Our results point to frequent reassortment and segment turnover, some of which appear to be driven by selective sweeps and serial hitchhiking. Particularly, we found evidence for a recent selective sweep affecting segment 5 and its encoded NS1 protein that has allowed a single variant to essentially invade the full range of BTV genomic backgrounds and serotypes currently circulating in India. In contrast, diversifying selection was found to play an important role in maintaining genetic diversity in genes encoding outer surface proteins involved in virus interactions (VP2 and VP5, encoded by segments 2 and 6, respectively). Our results support the role of reassortment in driving rapid phenotypic change in segmented viruses and generate testable hypotheses for in vitro experiments aiming at understanding the specific mechanisms underlying differences in fitness and selection across viral genomes.

Facile synthesis of molybdenum disulfide (MoS2) quantum dots and its application in humidity sensing.

Molybdenum disulfide (MoS2) quantum dots (QDs) are successfully synthesized by facile synthesis using ultrasonication assisted liquid exfoliation technique. The high and low boiling point solvents: N-methyl-pyrrolidone (NMP) and ethanol-water solution have been used for synthesis of MoS2 QDs. Similar size distribution of MoS2 QDs synthesized in two different solvents have been observed from the transmission electron microscopy and average size of these QDs are ∼5 nm. The film of MoS2 QDs is used to fabricate humidity sensor. The large edge to volume ratio and high surface active sites of QDs enhanced the water adsorption even at low humidity environment (<37% RH). The humidity sensing analysis shows that sensing film of MoS2 QDs synthesized in ethanol-water has an average sensitivity of 2.78 MΩ/%RH with fast response time (11 s), good repeatability and high stability. In view of these results, the work is highly applicable to fabricate high performance MoS2 QDs humidity sensor.

Functionalized magnetic nanomaterials for rapid and effective adsorptive removal of fluoroquinolones: Comprehensive experimental cum computational investigations.

Alarming growth of pharmaceutical residues in aquatic environment has elevated concerns about their potential impact on human health. Taking cognizance of this, the present study is focussed on the coating of cobalt ferrite nanoparticles with different functionalities and to use them as adsorbents for pharmaceutical waste. The thickness of the coating was analysed using Small angle X-ray scattering technique. Thorough study of the isotherms and kinetics were performed suggesting monolayer adsorption and pseudo kinetic order model, respectively. To get an insight of the interactions liable for adsorption of fluoroquinolones over the functionalized magnetic nanoparticles computational studies were undertaken. The results demonstrated substantial evidence proposing remarkable potential of these nanostructures as adsorbents for different pollutants with an additional advantage of stability and facile recoverability with a view to treat wastewater.

An alkali tolerant α-l-rhamnosidase from Fusarium moniliforme MTCC-2088 used in de-rhamnosylation of natural glycosides.

Analkali tolerant α-l-rhamnosidase has been purified to homogeneity from the culture filtrate of a new fungal strain, Fusarium moniliforme MTCC-2088, using concentration by ultrafiltration and cation exchange chromatography on CM cellulose column. The molecular mass of the purified enzyme has been found to be 36.0 kDa using SDS-PAGE analysis. The Km value using p-nitrophenyl-α-l-rhamnopyranoside as the variable substrate in 0.2 M sodium phosphate buffer pH10.5 at50 °C was 0.50 mM. The catalytic rate constant was15.6 s-1giving the values of kcat/Km is 3.12 × 104M-1 s-1. The pH and temperature optima of the enzyme were 10.5 and 50 °C, respectively. The purified enzyme had better stability at 10 °C in basic pH medium. The enzyme derhamnosylated natural glycosides like naringin to prunin, rutin to isoquercitrin and hesperidin to hesperetin glucoside. The purified α-l-rhamnosidase has potential for enhancement of wine aroma.

Periodontal thermoresponsive, mucoadhesive dual antimicrobial loaded in-situ gel for the treatment of periodontal disease: Preparation, in-vitro characterization and antimicrobial study.

BACKGROUND: This study aimed to formulate and characterize in-situ gel containing levofloxacin and metronidazole to release drugs in controlled manner for treatment of periodontitis. MATERIAL AND METHODS: Medicated in-situ gel with levofloxacin (10% w/v), metronidazole (25% w/v) and vehicle in-situ gel without drugs having poloxamer 407 (20% w/v) and chitosan (0.5%, 1%, 1.5%, 2.0% 2.5% w/v) were prepared and characterized for physicochemical, mechanical properties, stability and in-vitro drug release. Fourier transform infrared spectroscopy and differential scanning calorimetery studies were done. Optimized formulation was evaluated by scanning electron microscope (SEM) and in-vitro antimicrobial activity against 5 bacterial strains. RESULTS: The results revealed that drugs and polymers were compatible to formulate. All formulations were light yellow, clear and syringeable except formulation having 2.5% w/v chitosan. pH was in the range of 6.20 to 6.74. 1.0% w/v and 1.5% w/v chitosan formulations showed gelation temperature 37 ± 0.32 °C and 34 ± 0.21 °C. Further, mucoadhesive strength indicated mucoadhesivity of gel. In-vitro release study of 1.5% w/v chitosan formulation showed initial burst where about 55-60% MZ and 60-70% LVF got released within 6-7 hrs followed by sustained release upto 48 hrs. SEM images of 1.5% w/v chitosan optimized medicated in-situ and vehicle in-situ gel appeared similar indicating homogeneous mixing of polymers with drugs. In-vitro antimicrobial study showed that medicated in-situ gel was more effective than vehicle. CONCLUSIONS: In conclusion, optimized 1.5% w/v chitosan in-situ gel was thermoresponsive, mucoadhesive, syringeable, and released drugs in slow and controlled manner with effectiveness against broad range of microbes.