DKCNN: Improving deep kernel convolutional neural network-based COVID-19 identification from CT images of the chest.

BACKGROUND: An efficient deep convolutional neural network (DeepCNN) is proposed in this article for the classification of Covid-19 disease. OBJECTIVE: A novel structure known as the Pointwise-Temporal-pointwise convolution unit is developed incorporated with the varying kernel-based depth wise temporal convolution before and after the pointwise convolution operations. METHODS: The outcome is optimized by the Slap Swarm algorithm (SSA). The proposed Deep CNN is composed of depth wise temporal convolution and end-to-end automatic detection of disease. First, the datasets SARS-COV-2 Ct-Scan Dataset and CT scan COVID Prediction dataset are preprocessed using the min-max approach and the features are extracted for further processing. RESULTS: The experimental analysis is conducted between the proposed and some state-of-art works and stated that the proposed work effectively classifies the disease than the other approaches. CONCLUSION: The proposed structural unit is used to design the deep CNN with the increasing kernel sizes. The classification process is improved by the inclusion of depth wise temporal convolutions along with the kernel variation. The computational complexity is reduced by the introduction of stride convolutions are used in the residual linkage among the adjacent structural units.

Synthesis of Alkyl and Aryl Boronate Esters via CeO2-Catalyzed Borylation of Alkyl and Aryl Electrophiles Including Alkyl Chlorides.

A recyclable protocol using a CeO2-nanorod catalyst for borylation of alkyl halides with B2pin2 (pin = OCMe2CMe2O) is reported. A wide range of synthetically useful alkyl boronate esters are readily obtained from primary and secondary alkyl electrophiles, including unactivated alkyl chlorides, demonstrating broad utility and functional group tolerance. Preliminary investigation revealed an involvement of in situ formed catalytically active boryl species. The catalyst can be reused for up to six runs without appreciable loss in activity. In addition, we have demonstrated the use of this recyclable catalyst for the borylation of aryl halides with B2pin2, providing valuable aryl boronate esters under neat conditions.

Tuning the Surface Functionality of Fe3O4 for Sensitive and Selective Detection of Heavy Metal Ions.

The functionalization of materials for ultrasensitive detection of heavy metal ions (HMIs) in the environment is crucial. Herewith, we have functionalized inexpensive and environmentally friendly Fe3O4 nanoparticles with D-valine (Fe3O4-D-Val) by a simple co-precipitation synthetic approach characterized by XRD, FE-SEM, and FTIR spectroscopy. The Fe3O4-D-Val sensor was used for the ultrasensitive detection of Cd+2, Pb+2, and Cu+2 in water samples. This sensor shows a very low detection limit of 11.29, 4.59, and 20.07 nM for Cd+2, Pb+2, and Cu+2, respectively. The detection limits are much lower than the values suggested by the world health Organization. The real water samples were also analyzed using the developed sensor.

Recent advances in the chemistry of the phosphaethynolate and arsaethynolate anions.

Over the past decade, the reactivity of 2-phosphaethynolate (OCP-), a heavier analogue of the cyanate anion, has been the subject of momentous interest in the field of modern organometallic chemistry. It is used as a precursor to novel phosphorus-containing heterocycles and as a ligand in decarbonylative processes, serving as a synthetic equivalent of a phosphinidene derivative. This perspective aims to describe advances in the reactivities of phosphaethynolate and arsaethynolate anions (OCE-; E = P, As) with main-group element, transition metal, and f-block metal scaffolds. Further, the unique structures and bonding properties are discussed based on spectroscopic and theoretical studies.

Glucose oxidase mimicking half-sandwich nickel(II) complexes of coumarin substituted N-heterocyclic carbenes as novel molecular electrocatalysts for ultrasensitive and selective determination of glucose.

Glucose oxidase mimicking nickel-based porous structures with organic anchors are developed as cheap and reliable electrochemical sensors for the quantitative detection of glucose. A series of sterically and electronically modulated, air- and moisture-stable half-sandwich nickel(II) NHC complexes were prepared and characterized. Under the optimized electrocatalytic conditions, the nickel complex immobilized glassy carbon electrodes (GCEs) displayed high sensitivity (0.663, 1.280, 1.990 and 0.182 µA/µM) towards glucose detection, which is much higher than that of 3D porous nickel networks. The limit of detection of modified GCEs is found in the range 1.56-2.09 µM with much wider linear sensing range, and having a catalytic rate constant of 0.273 × 103 M-1s-1. Finally, the selectivity of the modified GCEs towards glucose in presence of other blood constituents was also evaluated.

A Stability-Indicating UPLC Method for the Determination of Potential Impurities and Its Mass by a New QDa Mass Detector in Daclatasvir Drug Used to Treat Hepatitis C Infection.

A stability-indicating ultraperformance liquid chromatographic method has been developed for the quantitative determination of degradation products and process-related impurities of daclatasvir in a pharmaceutical dosage form. Chromatographic separation was achieved on a polar Waters ACQUITY BEH phenyl 100 × 2.1 mm, 1.7-µm column using the gradient program consisting of mobile phase A: 0.03 M sodium perchlorate with 0.002 M of 1-octanesulfonic acid sodium salt (pH 2.5 buffer) and mobile phase B: 0.03 M sodium perchlorate with 0.02 M of 1-octanesulfonic acid sodium salt (pH 2.5 buffer) with acetonitrile in the ratio of 20:80% v/v. A flow rate of 0.4 mL/min is maintained under ultraviolet detection at 305 nm. The run time was 15 min, within which daclatasvir, its related impurities and unknown degradants were well resolved. The method was found to produce symmetric and sharp peaks with good separation between process-related impurities and degradation impurities. Samples were subjected to hydrolysis (acid and base), oxidative, photolytic and thermal stress conditions to prove the stability-indicating nature of the method. The unknown degradation products were identified by PDA/QDa mass detector. This mass spectrum reveals protonated molecular ion peaks [M + H]+ at m/z DP1-582.4 in acid and base hydrolyses and m/z DP2-778.5 in peroxide hydrolysis. The method was validated in terms of specificity, precision, linearity, accuracy, limit of detection, limit of quantification and robustness as per ICH guidelines.

Hydrogels of polyaniline with graphene oxide for highly sensitive electrochemical determination of lead ions.

Conducting polymers with graphene/graphene oxide hydrogels represent a unique class of electrode materials for sensors and energy storage applications. In this article, we report a facile in situ method for the polymerisation of aniline resulting in the decoration of 1D conducting polyaniline (PANI) nanofibers onto the surface of 2D graphene oxide (GO) nanosheets followed by hydrogel formation at elevated temperature. The synthesized nanomaterial exhibits significant properties for the highly sensitive electrochemical determination as well as removal of environmentally harmful lead (Pb2+) ions. The square wave anodic stripping voltammetry (SWASV) determination of Pb2+ ions showed good electroanalytical performance with two linear ranges in 0.2-250 nM (correlation coefficient = 0.996) and 250-3500 nM (correlation coefficient = 0.998). The developed protocol has shown a limit of detection (LOD) of about 0.04 nM, which is much lower than that of the World Health Organization (WHO) threshold limits. The prepared electrode showed an average of ∼99.4% removal of Pb2+ ions with a relative standard deviation (RSD) of 3.4%. Selectivity of the electrode towards Pb2+ ions were tested in presence of potential interferences such as Na+, K+, Ca2+, Mg2+, Cu2+, Cd2+, Hg2+, Zn2+, Co2+, Ni2+, Fe2+ and Fe3+ of similar and higher concentrations. The sensor showed good repeatability and reproducibility. The developed protocol was used to analyse samples from industrial effluents and natural water samples. The results obtained were correlated with atomic absorption spectroscopy (AAS).

Serosurveillance of foot and mouth disease in Karnataka state, India: a 3 years study.

A prospective serological investigation was conducted to determine the prevalence and distribution of foot-and-mouth disease (FMD), as well as to monitor the effectiveness of the FMD control programme (FMD-CP) through vaccination in Karnataka, India. Random serum samples were collected every year between May and August before the start of vaccination in 2011, and subsequently following two phases of vaccination in 2012 and 2013. Infection status (seroprevalence) was inferred by subjecting the sera to indirect r3AB3 non-structural protein-ELISA, using kits developed by the Project Directorate on FMD, India. The seromonitoring of FMD-CP was carried out by detecting antibodies deemed to be protective in the pre- and post-vaccinal sera, using liquid-phase blocking-ELISA for structural proteins. The results revealed significant decrease in seroprevalence from 58 to 21 %, providing more definitive data supporting our earlier findings obtained through clinical observations (Hegde et al. in Virusdisease 25:504-509, 2014), and detecting active infection in some of the populations which were considered to be free based on passive surveillance. On the other hand, after four rounds of vaccination, a gradual and significant increase from 4.5 to 59 % of animals carrying antibody levels deemed to be protective was observed against all the three serotypes. The findings of this study could be useful for further strategizing to strengthen the ongoing FMD-CP in Karnataka State, India.

Surface Passivation of MoO3 Nanorods by Atomic Layer Deposition toward High Rate Durable Li Ion Battery Anodes.

We demonstrate an effective strategy to overcome the degradation of MoO3 nanorod anodes in lithium (Li) ion batteries at high-rate cycling. This is achieved by conformal nanoscale surface passivation of the MoO3 nanorods by HfO2 using atomic layer deposition (ALD). At high current density such as 1500 mA/g, the specific capacity of HfO2-coated MoO3 electrodes is 68% higher than that of bare MoO3 electrodes after 50 charge/discharge cycles. After 50 charge/discharge cycles, HfO2-coated MoO3 electrodes exhibited specific capacity of 657 mAh/g; on the other hand, bare MoO3 showed only 460 mAh/g. Furthermore, we observed that HfO2-coated MoO3 electrodes tend to stabilize faster than bare MoO3 electrodes because nanoscale HfO2 layer prevents structural degradation of MoO3 nanorods. Additionally, the growth temperature of MoO3 nanorods and the effect of HfO2 layer thickness was studied and found to be important parameters for optimum battery performance. The growth temperature defines the microstructural features and HfO2 layer thickness defines the diffusion coefficient of Li-ions through the passivation layer to the active material. Furthermore, ex situ high resolution transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, and X-ray diffraction were carried out to explain the capacity retention mechanism after HfO2 coating.

Environmentally benign synthesis, molecular properties prediction and anti-inflammatory activity of novel isoxazolo[5,4-d]isoxazol-3-yl-aryl-methanones via vinylogous Henry nitroaldol adducts as synthons.

Synthesis of novel 6-methylisoxazolo[5,4-d]isoxazol-3-yl-aryl-methanones 5 has been achieved via nitro-nitrite rearrangement by utilizing vinylogous nitroaldol adducts as synthons under mild conditions. Furthermore, the new series of compounds 5a-i were assessed for molecular properties prediction, drug-likeness by Molinspiration (Molinspiration, 2008) & MolSoft (MolSoft, 2007) softwares, lipophilicity and solubility parameters using ALOGPS 2.1 program. The new series of compounds 5a-i were screened for their anti-inflammatory activity.

A facile synthesis, anti-inflammatory and analgesic activity of isoxazolyl-2,3-dihydrospiro[benzo[f]isoindole-1,3'-indoline]-2',4,9-triones.

A new series of isoxazolyl-2,3-dihydrospiro[benzo[f]isoindole-1,3'-indoline]-2',4,9-triones (14) were synthesized by reaction of 4-amino-3-methyl-5-styrylisoxazole 10 with chloroacetic acid followed by a three component reaction with substituted isatins 12 and 1,4-naphthoquinone 13 using Ceric ammonium nitrate (CAN) catalyst under aerial oxidation condition. Structures of these compounds were established on the basis of IR, (1)H NMR, (13)C NMR and mass spectral data. The title compounds 14a-j were evaluated for their anti-inflammatory and analgesic activity. Compounds 14d, 14e and 14f exhibited potent anti-inflammatory and analgesic activity as that of standard drugs.

Electrochemical synthesis of thiol-monolayer-protected clusters of gold.

We have synthesized for the first time thiol-monolayer-protected gold nanoparticles (MPCs) by the process of electrochemical dissolution of gold in an ethanol-water mixture. The MPCs have been formed both with and without NaBH4 as a reducing agent. The well-dispersed thiol-capped MPCs were characterized by UV-visible absorption and transmission electron microscopy (TEM) studies.

Separation, characterization, and quantitation of process-related substances of the anti-hypertensive drug doxazosin mesylate by reversed-phase LC with PDA and ESI-MS as detectors.

A simple and rapid reversed-phase liquid chromatography (LC) method with photodiode array (PDA) and electrospray ionization (ESI)-mass spectrometry (MS) as detectors was developed and validated to separate, identify, and quantitate the related substances of Doxazosin mesylate (DXZN) for monitoring the reactions involved during process development. The high-performance liquid chromatography profiles of related-substances of DXZN are used as fingerprints to follow the procedures used in the manufacturing units. The separation is accomplished on an Inertsil ODS-3 column with acetonitrile-ammonium acetate (10 mM, pH 4.0) as the mobile phase, using a gradient elution mode and monitoring the eluents by a photodiode array detector at 265 nm at ambient temperature. LC-ESI-MS-MS is used to identify the additional impurities formed during the synthesis. The identified impurities were synthesized and characterized by UV, Fourier transform-IR, 1H NMR, and MS data. The detection limits for the impurities are 0.74 - 4.14 x 10(-9) g, and the method is found to be suitable not only for the monitoring of synthetic reactions, but also for quality assurance of DXZN in bulk drugs and formulations.

Liquid-chromatographic separation and determination of process-related impurities, including a regio-specific isomer of celecoxib on reversed-phase C18 column dynamically coated with hexamethyldisilazane.

A simple and rapid reversed-phase high-performance liquid-chromatographic method for the separation and determination of process-related impurities of celecoxib (CXB) in bulk drugs and pharmaceuticals was developed. The separation of impurities viz., 4-methylacetophenone (I), 1-(4-methylphenyl)-4,4,4-trifluorobutane-1,3-dione (II), 4-hydrazinobenzene sulfonamide (III) and a regio-specific isomer [3-(4-methylphenyl)-5-trifluoromethyl-1H-pyrazole-1-yl]-benzenesulfonamide (IV), was accomplished on an Inertsil ODS-3 column dynamically coated with 0.1% hexamethyldisilazane (HMDS) in acetonitrile:water (55:45 v/v) as a mobile phase and detection at 242 nm using PDA at ambient temperature. The chromatographic conditions were optimized by studying the effects of HMDS, an organic modifier, time of silanization and column temperature. The method was validated and found to be suitable not only for monitoring the synthetic reactions, but also to evaluate the quality of CXB.

An improved and validated LC method for resolution of bicalutamide enantiomers using amylose tris-(3,5-dimethylphenylcarbamate) as a chiral stationary phase.

An improved HPLC method for determination of enantiomeric purity of bicalutamide in drugs and pharmaceuticals was developed and validated. Baseline separation with resolution >/=6.0 was achieved within 10 min on Chiralpak AD-H (250 mm x 4.6 mm; particle size 5 microm) column using n-hexane:2-propanol (65:35 v/v) as mobile phase at a flow rate of 1.0 ml/min at 25 degrees C. The detection was made at 270 nm using UV detector while a polarimetric detector connected in series was used for identification of enantiomers. The effects of 2-propanol, ethanol and temperature on enantioselectivity and resolution of enantiomers were evaluated. The method was validated in terms of accuracy, precision and linearity in the range of 10-250 microg/ml and the r(2) was >0.9999. The recoveries were 99.68-100.25% with <1% R.S.D. The limits of detection (LOD) and quantification (LOQ) of enantiomers were (2.4, 3.0 and 7.6, 9.3) x 10(-8)g/ml for (S)-(+)-BCT and (R)-(-)-BCT enantiomers, respectively. The method was found to be suitable for rapid determination of enantiomeric purity of bicalutamide in bulk drugs and pharmaceutical formulations.

Enantiomeric resolution of doxazosin mesylate and its process-related substances on polysaccharide chiral stationary phases.

High-performance liquid chromatographic methods for separation of racemic doxazosin mesylate and its synthetic precursors on polysaccharide based stationary phases viz., amylose tris-(3,5-dimethylphenylcarbamate) (Chiralpak AD-H) and cellulose tris-(3,5-dimethylphenylcarbamate) (Chiralcel OD-H) were developed. The base line separation with Rs>1.50 was obtained using a mobile phase containing n-hexane-alcohol-0.1% diethylamine (ethanol, 1-propanol and 2-propanol) in various proportions. The effect of concentration of the alcoholic modifiers on the resolution was studied. A good separation was achieved on amylose based Chiralpak AD-H column when compared with cellulose based Chiralcel OD-H. The effects of structural features of the solutes and solvents on discrimination between the enantiomers were examined. The detection was carried out at 240 nm with UV detector while identification by polarimetric detector connected in series. The method was suitable not only for process development of doxazosin mesylate but also determination of enantiomeric purity of bulk drugs and pharmaceuticals.

Development and validation of a liquid chromatographic method for determination of enantiomeric purity of citalopram in bulk drugs and pharmaceuticals.

A simple, rapid and robust LC method for enantiospecific separation and determination of citalopram in drugs and pharmaceuticals was developed using UV and polarimetric detectors connected in series. Baseline separation with resolution > or = 3.0 was achieved within 20 min on Chiralcel OD-H (250 mm x 4.6 mm) 5 microm column using a mobile phase containing of n-hexane:2-propanol:triethylamine (TEA) (95:05:0.1 v/v/v) at a flow rate of 1.0 ml/min at 25 degrees C. Effects of 2-propanol, triethylamine and temperature on enantioselectivity and resolution of the enantiomers were evaluated. Clopidogrel hydrogen sulphate was used as an internal standard (IS) for quantitative determinations using UV detector at 240 nm. Polarimetric detector was used for identification of enantiomers. The limits of detection (LOD) and quantification (LOQ) were 0.5 and 1.3 microg/ml respectively for both the enantiomers. The linearity of the method was in the range of 50-600 microg/ml with r2 > 0.9999. The inter- and intra-day assay precision was less than 0.63% (%R.S.D.) and recoveries were in the range 99.38-100.41%. The method was validated and found to be suitable for determination enantiomeric purity of citalopram in bulk drugs and pharmaceutical formulations.

Enantioselective determination of a gastroprokinetic drug using amylose tris-(3,5-dimethylphenylcarbamate) as a stationary phase by HPLC.

An enantioselective high-performance liquid chromatographic method for determination of enantiomers of mosapride citrate in bulk drugs and pharmaceuticals using UV-vis and polarimetric detectors in series has been developed. Baseline separation with resolution >2.0 was achieved on a column containing amylose tris-(3,5-dimethylphenylcarbamate) as stationary phase using a mobile phase consisting of n-hexane:ethanol:triethylamine (80:20:0.3, v/v/v) at 40 degrees C. The detection was carried out at UV-276 nm and enantiomers were identified by polarimetric detector. The effect of ethanol, 2-propanol, TEA, temperature and mobile phase flow rate on separation of MSP enantiomers was studied and the method was validated with respect to accuracy, precision, linearity and limits of detection and quantification. The linearity of the method was studied between 6.25 and 50 microg/ml and r2 was >0.9997. The recoveries were in the range 99.63-100.22%, the method was suitable not only for process development of mosapride citrate but also for quality assurance of the individual enantiomers in bulk drugs and pharmaceuticals.

Enantiospecific resolution of rabeprazole by liquid chromatography on amylose-derived chiral stationary phase using photo diode array and polarimetric detectors in series.

A simple and rapid liquid chromatographic method for enantioselective separation and determination of R-(+) and S-(-) enantiomers of rabeprazole in drugs and pharmaceuticals using photo diode array (PDA) and polarimetric detectors connected in series was developed. Chiralpak AD-H (250mmx4.6mm) 5mum column packed with amylose tris(3,5-dimethylphenyl carbamate) as a stationary phase and the mobile phase containing n-hexane:ethanol:2-propanol(75:15:10, v/v/v) in an isocratic mode has yielded baseline separation with resolution greater than 3.0 at 40 degrees C. Effects of ethanol, 2-propanol and temperature on separation were studied for optimum resolution. Lansoprazole sulphone was used as an internal standard (IS) for quantitative determination of individual enantiomers in bulk drugs as well as pharmaceutical formulations. The method was validated in terms of accuracy, precision and linearity according to ICH guidelines. The linearity of the method was studied in the range of 0.5-50mug/ml and the r(2) was >0.9997. The inter- and intra-day precision of assay were determined (R.S.D.<1%) and the recoveries were in the range of 99.63-100.22% with <1% R.S.D. The limits of detection (LOD) and quantification (LOQ) were 0.02mug/ml and 0.07mug/ml for both the enantiomers, respectively.

Development and validation of a reversed-phase liquid chromatographic method for separation and simultaneous determination of COX-2 inhibitors in pharmaceuticals and its application to biological fluids.

An isocratic reversed-phase high-performance liquid chromatographic method has been developed for separation and simultaneous determination of COX-2 inhibitors, viz., celecoxib, rofecoxib, valdecoxib, nimesulide and nabumetone, using 4-chloro-2-nitroaniline as internal standard. Good chromatographic separation was achieved using a reversed-phase Inertsil C(18) column with mobile phase consisting of methanol and 0.05% aqueous glacial acetic acid (68:32 v/v) using photodiode array (PDA) detector at 230 nm. It was validated with respect to accuracy, precision, linearity, limit of detection and quantification. The linearity range was found to be 1.0--20 microg/mL and the percentage recoveries were between 97.55 and 100.14. The method is suitable not only for the estimation of active ingredients in pharmaceutical dosage forms but also in vitro estimations in human plasma. It is simple, rapid, selective and capable of detecting and determining COX-2 inhibitors with a detection limit of 0.127--1.040 microg/mL simultaneously.