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Polymorphism‐dependent cytotoxicity and cellular uptake of drug molecules have been studied for the past two decades. However, the visualization of polymorph‐dependent cellular uptake and cytotoxicity using microscopy imaging techniques has not yet been reported. The luminescent polymorph is an ideal candidate to validate the above hypothesis. Herein, we report the polymorph‐dependent cellular uptake, cytotoxicity, and bio‐imaging functions of polymorphs 1Y and 1R of a naphthalimide‐phenothiazine dyad. These polymorphs show different luminescence colors in the solid state and exhibit aggregation‐induced enhanced emission (AIEE) in the DMSO‐Water mixture. Bioimaging, cytotoxicity assay, and fluorescence‐activated cell sorting (FACS) studies revealed that these polymorphs show different levels of cytotoxicity, cellular uptake, localization, and imaging potential. Detailed photophysical, morphological, and biological studies revealed that the difference in molecular conformation in these polymorphs enables them to form aggregates of different sizes and morphology, which leads to the differential uptake of these into the cells and consequently shows different cytotoxicity and imaging potentials. [ABSTRACT FROM AUTHOR]

We consider the following chemotaxis-haptotaxis system: { u t = ∇ ⋅ (D (u) ∇ u) − χ ∇ ⋅ (S (u) ∇ v) − ξ ∇ ⋅ (u ∇ w) , x ∈ Ω , t > 0 , v t = Δ v − v + u , x ∈ Ω , t > 0 , w t = − v w , x ∈ Ω , t > 0 , under homogeneous Neumann boundary conditions in a bounded domain Ω ⊂ R n , n ≥ 3 with smooth boundary. It is proved that for S (s) D (s) ≤ A (s + 1) α for α < 2 n and under suitable growth conditions on D , there exists a uniform-in-time bounded classical solution. Also, we prove that for radial domains, when the opposite inequality holds, the corresponding solutions blow-up in finite or infinite-time. We also provide the global-in-time existence and boundedness of solutions to the above system with small initial data when D (s) = 1 , S (s) = s. [ABSTRACT FROM AUTHOR]

We consider fully parabolic two‐species chemotaxis system with p$$ p $$‐Laplacian diffusion in a smooth bounded domain Ω⊂ℝn,n≥2$$ \Omega \subset {\mathrm{\mathbb{R}}}&#x0005E;n,n\ge 2 $$ with 1

The paper presents a scalable and generalized approach to social network analysis using fuzzy graph theory. It proposes an intelligent sociocentric approach that calculates the degree of potential relationship of a social network of finite size by proposing a fuzzy graph social network model. It takes into account social entity functional and relational attributes simultaneously. It computes the degree of potential relationship of a social network in two steps. The first step computes the fuzzy pairwise relationship between all social nodes or entities by incorporating the proposed fuzzy node activeness index parameter with an online and offline communication relationship. The second step further uses all fuzzy pairwise relationships calculated in the first step to calculate the degree of potential relationship of a social network. It uses an astute function that utilizes weighted arithmetic and geometric means of the relationships between entities. It also uses two weights—betweenness and closeness centrality of an entity in the social network. The paper performs the experimental work on a small WhatsApp social network of undergraduate students in the university for 6 months. Hence, the paper proposes the degree of potential relationship in social networks, which may be used as a global parameter to compare different social networks by simultaneously incorporating social node's functional and relational attributes. [ABSTRACT FROM AUTHOR]

A carbamate-linked-bistriazole (5) was prepared by click reaction of diethynyl 1,3-phenylenedicarbamate (2) and phenyl azide derivative (4) in DMF/H2O using copper sulfate and sodium ascorbate as a catalyst at room temperature for fluoride ion sensing. The structural analysis of synthesized compound was done by using 1HNMR, 13C NMR, FTIR and HRMS. The sensing behavior of carbamate-linked-bistriazole (5) was examined by 1HNMR, UV–vis and fluorescence study. NMR titration study suggested the participation of triazole, amide and aromatic protons in binding of fluoride ion. UV–visible study established the 1:1 complexation ratio between sensor 5 and F– ion with stability constant K of 2.64 × 104 M−1 and detection limit in µM range (9.372 µM). Further, fluorescence titration for 5 (9.2 × 10−6 M) with fluoride ions exhibited an emission quenching at 424 nm along with small bathochromic shift. Density functional theory (DFT) calculations also confirmed interaction mechanism in 5a-F– complex established by, UV–visible, 1H NMR and fluorescence studies. [ABSTRACT FROM AUTHOR]

Background: It is well known that the prevalence of gestational diabetes mellitus (GDM) varies greatly depending on geographic location, dietary preferences, and socioeconomic status. In order to ascertain the prevalence of GDM and risk factors connected to it in women visiting an antenatal care (ANC) clinic in the Chengalpattu region, this study was conducted. Methods: Women who were receiving antenatal care (ANC) at a clinic and had an estimated gestational age between 24 and 28 weeks were participated in this study. Women who agreed to participate were informed before undergoing a conventional 2-hour, 75-gram oral glucose tolerance test (OGTT). A proforma was filled out with general information including demographics, socioeconomic status, level of education, parity, family history of diabetes and/or hypertension, and history of GDM. GDM was diagnosed using the 75 g 2-h OGTT criteria set out by the American Diabetes Association (ADA). Results: In all, 607 women took part in the study, and 43 (7.1%) of them had GDM. Additional 66 (10.87%) women showed a single abnormal value. Age, educational level, socioeconomic status, pre-pregnancy weight and BMI, weight gain, acanthosis nigricans, family history of diabetes or hypertension, and past history of GDM were risk factors that were found to be significantly associated with GDM on bivariate analysis; however, on multivariate analysis, only upper middle class and the presence of acanthosisnigricans were found to be significantly associated with GDM. Conclusion: A tertiary care hospital found that 7.1% of patients had GDM. Control and risk factor modification require the right interventions. [ABSTRACT FROM AUTHOR]

Introduction: Dengue presents with a variable clinical course, ranging from mild illness to potentially fatal hemorrhage and shock. We aimed to evaluate the capabilities of various hematological parameters observed early in the course of illness for predicting the clinical outcomes of illness. Material and Method: In our study total 100 cases aged from 0 to 18 years who had diagnosed to have dengue fever were taken. The presenting clinical features were collected and analyzed. The laboratory results analyzed were blood count including Hemoglobin level, hematocrit level, leucocyte count and platelet count. Results: In the present study, 29/100 (29.0%) cases were of dengue without warning sign, 49/100 (49.0%) were dengue with warning signs and 22/100 (22.0%) were of severe dengue. Patient age ranged from 0-18 years. Majority, 52/100 (52.0%) were among 6-8 years. Males were affected more than females (55% boys and 45% were girls). Severe thrombocytopenia was seen in 57.0 % of cases and raised hematocrit (>47%) was observed in 22.0 % cases. Most of the cases 65 (65.0%) were noted in August and September. Conclusion: We identified important clinical presentations and useful hematological parameters to enable the early prediction for outcome in children with dengue. An accurate diagnosis using these data will enable further investigation to be tailored and early treatment for the patient. [ABSTRACT FROM AUTHOR]

Health monitoring systems are improving with the development of the internet of things. This paper proposes a secure architecture consisting of a four-layer internet of things enabled health monitoring system that collects patient data and classifies them into different medical categories. While collecting patient information from their wearable smart sensing devices for computation, the privacy and security of this process are essential. The main motive of this paper is to develop a lightweight and secure communication protocol using blockchain architecture for decentralized IoT networks and classify them into different categories using transfer learning. We propose a framework that uses blockchain for security and incorporates transfer learning to use multiple pre-trained models. The proposed routing technique uses factors like probability, credibility rating, and node energy to route the data to its destination such that the network overhead is reduced and the energy used is minimal. We classify the collected patient information using four different pre-trained convolutional neural network models: ResNet50, VGG19, InceptionV3, and SqueezeNet. We simulate the proposed routing approach and other benchmark schemes on various performance metrics. The results show that the proposed approach gives 92.24% classification accuracy. [ABSTRACT FROM AUTHOR]

An Ultra-High-Performance Liquid Chromatography (UHPLC) method was developed and validated as per ICH guidelines for the analysis of 16 PAH compounds as per USEPA and various soil samples were analyzed in Manesar located 60 km away from Delhi, capital of India 28.3542° N, 76.9400° E in different seasons. The sampling was done in the industrial areas, agricultural fields, and residential plots all within 10 km radius of the industrial area. In the present study, the QuEChERS method was used for sample preparation, which has shown good recoveries around 80 to 120% The extraction time was only 10 minutes, followed by the UHPLC technique of run time of just 16 minutes. Average PAH concentration in Manesar soil was found highest in the winter session of industrial areas. Σ16 PAH was 141 ppb in the industrial area in winter, 64 ppb in agricultural fields, and 54.7 ppb in residential plots. The lowest PAH levels were observed in the monsoon season. These values are very less if compared to Brazil, UK, Germany, and Korea. [ABSTRACT FROM AUTHOR]

Blockchain technology has unlocked the doors of building decentralized applications, where security plays a vital role. Any transaction ever created in a blockchain is recorded permanently. With the increasing usage of social media modalities today, many non-reputable sources create and publish fake and luring news. Due to the easy availability of the internet and excessive use of social media, fake news can spread like a flash. It causes the need to eliminate fake news posted on social media platforms. The main motive of the paper is to develop an ensemble model that assists in the automated identification of fake news. This paper addresses the identified gaps in detecting multi-modal fake news. We propose Fake News Network (FNNet) as a novel secure blockchain-based deep learning model to detect fake news. It uses blockchain and deep learning to assure data integrity and learn data representations, respectively. The proposed model consists of four layers: the node layer, the deep learning layer, the blockchain layer, and the network layer. This is an ensemble deep-learning model that leverages Bi-LSTM and CNN models, where the Bi-LSTM model captures the sequential data in both directions, and CNN captures the hidden features. We use Pheme, CrisisLexT6, and ISOT datasets to train the model. FNNet achieves an average accuracy of 86.93%, 92.22%, and 98.53% on Pheme, CrisisLexT9, and ISOT datasets, respectively. Our results show that the proposed model is robust and applicable to real-time datasets and social media networks to detect fake news effectively. [ABSTRACT FROM AUTHOR]

The current study is aimed to develop a green packaging material out of betel nut fiber waste that holds up to the values of commercial food packaging. Biocomposites of betel nut fiber were prepared with varying fiber concentrations of 9, 10 and 12% and subjected to utility-based mechanical, physical, morphological and storability tests using chilies for storage. The composite with 10% fiber content exhibited superior strength features with tensile strength, compressive strength, elastic modulus, nanohardness and minimum creep rate values of 1.59 MPa, 426.23 MPa, 2.032 GPa, 99.729 MPa and 37.02, respectively. It possessed a characteristic elasto-plastic and stress-strain behavior, favorable for storage and transportation. Along with the superior mechanical properties, the selected composite manifested a lower water vapor permeability of 4.635 × 10−9 g/msPa and a minimal sorption capacity of 51.01% in comparison with cardboard sheets (currently used packaging material for chilies). Chilies stored in developed betel nut fiber composite exhibited a significantly higher value of firmness and reduced value of degradation factors as compared to that in cardboard boxes. Hence, it can be concluded that bearing all the superior properties, the developed composite is more functional than the cardboard cartons for storage and transportation. [ABSTRACT FROM AUTHOR]

The introduction of fins and baffles on the absorber plate is an effective way to ameliorate the thermal performance of flat plate solar collector (FPSC), but obstructs the air passage leading to considerable pumping power penalty. In the current work, attempt is made to improve the overall performance of collector with the incorporation of hollow semicircular loop fins and rectangular baffles over the absorber plate for air mass flow rate ranging from 0.006 to 0.02 kg s−1. A parametric study was carried out with finite element approach considering different radius (2–4 cm), pitch (6–20 cm) and number of semicircular loops per row in transverse direction (3–8 loops). Compared to intermittent loops, placement of continuous staggered semicircular loops was more effective for attaining uniform profile and higher magnitude of air temperature at collector outlet. With regard to FPSC, finned collector provided 2.64–2.95 times greater Nusselt number and 41–75% higher thermal efficiency, as well as exhibited 8.38–10.4 K higher collector outlet average air temperature. The pressure drop noted for FPSC was 0.14 Pa and increased to the range of 0.5–0.7 Pa with the addition of loops and baffles at an air mass flow rate of 0.01 kg s−1. Collector having baffles and continuous semicircular loops of radius 3 cm, made up of 2-mm-thick wire, presented maximum thermohydraulic performance factor of 1.73 in conjunction with showing maximum magnitude and uniform profile of collector outlet temperature. The modified collector with semicircular loops along with baffles will find its application in efficient drying of agricultural commodities. [ABSTRACT FROM AUTHOR]

Present work is focused on the assessment of energy and exergy flow in a mixed-mode solar dryer during the drying of pineapple slices by utilizing first and second law of thermodynamics. Moreover, drying kinetics and effective moisture diffusivity with shrinkage correction were also investigated at natural convection (NC) and forced convection (FC) conditions. The initial moisture of pineapple slices (90%, wb) was reduced to 29.66, 23.06, 24.05 and 19.68% (wb) in 6.5 h under NC, air mass flow rates of 0.006, 0.01 and 0.015 kg/s, respectively. Results revealed that diffusivity determined by assuming negligible shrinkage demonstrated 3.5–5.3 times overestimation than shrinkage consideration. Energy analysis exhibited that about 55–78% of total input solar energy constituted thermal losses from the absorber plate. Remarkably, an increase of air mass flow rate caused an augmentation in useful heat gain by air and a simultaneous reduction in thermal losses from collector along with its efficiency improvement. Exergetic investigation of dryer identified that the exergy efficiency of the solar collector and drying chamber was positively influenced by increasing air velocity. Furthermore, exergy efficiency of the dryer for NC and drying air mass flow rate of 0.006, 0.01 kg/s was 85.45%, 46.15%, and 18.88% lesser than 0.015 kg/s, respectively. Image 1 • Exergy and energy assessments of mixed-mode solar dryer were attempted. • Pineapple samples lost more moisture at higher air velocity inside the dryer. • Rising of air mass flow rate increased the heat gain and reduced the thermal losses. • Dryer exergy efficiency at natural convection was 85.45% lesser than 0.015 kg/s. • Exergy destruction in drying chamber was estimated in the range of 142.31–151.35 W. [ABSTRACT FROM AUTHOR]

The present research deals with the analysis of 3-dimensional computational models to analyze the airflow, temperature profile of dryer coupled with heat transfer of pineapple slices during solar drying. A finite element approach performed the simulations of mixed-mode solar dryers integrated with flat plate and finned collectors consisting of baffles and semicircular loops under forced convection using COMSOL Multiphysics software. The mass transfer of pineapple slices was also simulated to compare the moisture distribution inside the samples dried in both solar dryers. The dryer integrated with flat plate collector (FPSC) presented 2.5 h longer drying period than the finned collector assisted dryer to attain the 10% (wb) moisture of pineapples slices. The airflow pattern indicated inadequate air distribution inside the FPSC and generated two vortices contributing to dead zones and localized heating inside the drying chamber. The finned collector provided a more effective air distribution in the dryer. The sample's temperature was greatly affected by their position because of non-homogenous temperature distribution in FPSC-Dryer and finned collector integrated dryer presented more uniform temperature profile. The results are beneficial for the analysis of uniformity of airflow and temperature in the dryer, which is a deciding factor for homogeneity of drying. [Display omitted] [ABSTRACT FROM AUTHOR]

• Effect of air mass flow rate on performance of solar collector was analyzed. • Thermal efficiency was in the range of 22.53–32.3% at varied air mass flow rate. • Correlation matrix was developed for thermal performance parameters. • Two principal components summarized relations among thermal performance parameters. • Thermal efficiency was more influenced by air mass flow rate than solar intensity. Present research focuses on the analysis of temperature profile, heat transfer characteristics and thermal efficiency of a flat plate solar air collector (FPSAC) at different air mass flow rates. Further, the interrelationship among several variables was also investigated using multivariate analysis. Experiments were performed with FPSAC at non-load conditions in the outdoor environment at natural convection (NC) and forced convection (FC) conditions. Air with mass flow rate (ṁ) of 0.01, 0.015 and 0.02 kg/s exhibited 30.73%, 57.88% and 96.40% enhanced convective heat transfer coefficient (h c,p-a) than 0.006 kg/s. Moreover, increase of ṁ from 0.006 kg/s to 0.02 kg/s augmented the thermal efficiency (η th) from 22.53 to 32.3%. With regard to 0.006 kg/s, air mass flow rate of 0.02 kg/s produced 8.6% and 4.3% reduced heat transfer coefficient from absorber plate to glass due to convection (h c,p-g) and radiation (h r,p-g). Pearson correlation analysis indicated a strong positive effect of solar intensity on the temperature of absorber plate, glass cover and outlet air of collector, but a weak correlation with collector inlet air temperature, useful heat gain, η th , and h c,p-a. Further, a positive correlation of solar intensity with h c,p-g and h r,p-g was also noticed. Principal component analysis enabled the visualization of association among solar intensity, temperature of different components of collector, heat transfer coefficients, thermal efficiency and time of the day. The analysis indicated that useful heat gain, heat transfer coefficient of air and thermal efficiency of the collector were not highly influenced by solar intensity. [ABSTRACT FROM AUTHOR]

Zeolites have taken a leading position in petrochemical, fine, and bulk chemical industries due to their porous architecture, pore sizes, tunable acidity, and thermal stability. Various strategies of zeolites preparation, including template‐free, solvent‐free, and toxic mineral‐free strategies are summarized. Moreover, the zeolite synthesis using naturally occurring minerals and sustainable natural templates is also discussed, which involves the synthesis of nanocrystalline zeolites of different framework structures using plant‐based natural templates and biomass‐derived renewable chemicals. Overall this personal account provides the fundamentals of various sustainable synthetic strategies reported in the literature for the synthesis of zeolites with suitable examples that will be useful for the students and will motivate experienced researchers to develop various novel sustainable methods for the synthesis of zeolites and other inorganic materials of industrial relevance. [ABSTRACT FROM AUTHOR]

Here, we report successful single crystal growth of new possible magnetic topological insulator (MTI) FeBi2Te4 by a self-flux method via a vacuum encapsulation process. The detailed Rietveld analysis of powder XRD data shows the as-grown MTI crystal to be mainly dominated by the FeBi2Te4 phase along with minority phases of Bi2Te3 and FeTe. Scanning electron microscope (SEM) image shows the morphology of as-grown MTI single crystal to be of layered type laminar structure. Raman spectroscopy of the crystal exhibited three distinct phonon modes at 65, 110, and 132 cm−1 along with two split secondary modes at 90, and 144 cm−1. The secondary split modes are the result of FeTe intercalation in the Bi2Te3 unit cell. Magnetoresistance (MR%) measurement has been performed at different temperatures, i.e., 200 K, 20 K, and 2 K in applied magnetic fields up to ± 12 Tesla, which showed very low MR in comparison with pure Bi2Te3 crystal. Temperature dependence of DC magnetization measurements shows the FeBi2Te4 crystal to be mainly of ferromagnetic (FM) or ferrimagnetic nature above 295 K, albeit a secondary weak magnetic transition is seen at 54–46 K as well. Detailed isothermal magnetization (MH) results showed that the FM saturation moment at 295 K is 0.00213 emu/g, which is nearly invariant until 400 K. In summary, we had grown an MTI FeBi2Te4 single crystal, which may be a possible entrant for the quantum anomalous Hall (QAH) effect at room temperature or above. [ABSTRACT FROM AUTHOR]

Introduction: Several studies regarding tumor-stroma ratio (TSR) in colorectal, esophageal, breast, endometrial, and cervical carcinomas have been done in the past with significant results.Objectives: The objectives of this study were to (1) study and grade TSR in buccal mucosa and tongue squamous cell carcinoma (SCC), (2) grade inflammatory cell infiltrate surrounding the tumor, and (3) correlate the above two parameters with tumor grade, lymph node metastasis, lymphovascular invasion (LVI), and perineural invasion (PNI).Materials and Methods: Totally, 25 patients of buccal SCC and 16 cases of tongue SCC were included in the study. TSR was assessed visually on the hematoxylin and eosin-stained tissue sections by two independent observers. Cases were categorized into two groups: One with high TSR >50% (stroma poor) and the other with low TSR <50% as the stroma-rich group. TSR was correlated with tumor size, lymph node metastasis, inflammatory cell infiltrate, LVI, and PNI. Data were analyzed by the Statistical Package for the Social Sciences version 16.0 (Chicago, IL, USA) for Windows. The Chi-square and Fischer's exact tests were applied in the analysis of categorical variable.Results and Conclusion: SCC of buccal mucosa showed a significant correlation between TSR and size of the tumor (P = 0.001). We found that smaller the tumor size ≤2 cm (Stage T1), lesser the TSR, and size >2 cm was found to be associated with higher TSR. Hence, higher TSR (stroma poor) was associated with an adverse pathological characteristic, i.e., advanced T significantly. There was no significant correlation between TSR and inflammatory infiltrate with grade of the tumor, lymph node metastasis, LVI, and PNI. In 16 cases of SCC of the tongue; no correlation was observed between TSR and inflammatory infiltrate with tumor size, grade of the tumor, lymph node metastasis, LVI, and PNI. TSR has been studied in various malignancies (mostly adenocarcinomas) including laryngeal SCCs; however, it has never been studied on oral SCCs. [ABSTRACT FROM AUTHOR]

The conversion of CO2 to useful chemicals, especially to atom economical products, is the best approach to utilize an excess of CO2 present in the atmosphere. In this study, a metal‐organic framework (ZIF‐8) is integrated with nanocrystalline zirconosilicate zeolite to develop an integrated porous catalyst for CO2 insertion reactions. The catalyst exhibits excellent activity for the CO2 insertion reaction of epoxide to produce cyclic carbonate in neat condition without the addition of any co‐catalyst. The catalyst is stable and recyclable during the cyclic carbonate synthesis. Further, the catalyst also exhibits very good activity in another CO2 insertion reaction to produce quinazoline‐2,4(1H, 3H)‐dione. [ABSTRACT FROM AUTHOR]

Zeolite-metal organic framework nanocomposite catalyst is developed for the synthesis of 2-((5-(hydroxymethyl)furan-2-yl)methylene)malononitrile from sucrose/fructose/glucose via one-pot cascade protocol. To accomplish this objective, zeolite Beta and Zr based metal- organic frameworks such as UiO-66 and UiO-66-NH 2 are investigated for the independent steps, i.e. the conversion of sucrose to HMF and the Knoevenagel condensation of HMF and malononitrile. Beta zeolite exhibits the best activity in the sucrose to HMF conversion, whereas UiO-66-NH 2 exhibits the best activity in the Knoevenagel condensation. Therefore, zeolite Beta and UiO-66-NH 2 are integrated to develop a highly sustainable and efficient multi-functional catalyst for the conversion of sucrose to 2-((5-(hydroxymethyl)furan-2-yl)methylene)malononitrile via one-pot cascade reaction. The composite catalyst contains the optimum acidity and basicity for the cascade reaction. The presence of both the frameworks in the composite material is confirmed by using various physico-chemical characterization techniques. Further, the integration of both the active frameworks enhances the chemical stability and recyclability of the composite catalyst in the cascade reaction. This study demonstrates a unique approach to develop a synthesis strategy for the integration of inorganic zeolite and MOFs to achieve the desired activity, selectivity, and stability of the developed catalyst. [ABSTRACT FROM AUTHOR]

We report successful growth of magnetic topological insulator (MTI) MnBi2Te4. The heating schedule basically deals with growth of the crystal from melt at 9000C and very slow cooling (10C/hr) to around 6000C with 24 hours hold time, followed by cooling to room temperature. Our detailed, PXRD Reitveld analysis showed that the resultant crystal is dominated mainly by MnBi2Te4 and minor phases of Bi2Te3 and MnTe. The transport measurements showed a step like behavior at around 150 K followed by cusp like structure in resistivity at around 25 K (TP) due reported anti-ferromagnetic ordering of Mn. Both the resistivity transitions are seen clearly in dρ/dT measurements at 150 K and 20 K, respectively. The 25 K transition of the compound is also seen in magnetic susceptibility. Low temperature (5 K) magneto-resistance (MR) in applied field of up to 6 Tesla exhibited –ve MR below 3 Tesla and + ve for higher fields. Also, seen are steps in MR below 1 Tesla. The studied MnBi2Te4 MTI crystal could be a possible candidate for quantum anomalous Hall (QAH) effect. [ABSTRACT FROM AUTHOR]

Context: Trauma-induced coagulopathy (TIC) is life-threatening in head injury patients, and there is a lack of Indian data on its incidence and outcome. Aims: In this study, incidence and outcome related to coagulopathy were assessed in patients with moderate-to-severe isolated traumatic brain injury (iTBI). Settings and Design: A prospective observational study carried out in patients admitted within 24 h of injury. Materials and Methods: One hundred patients with moderate-to-severe iTBI were included. Samples for coagulation tests (prothrombin time [PT], PT index [PTI], international normalization ratio [INR], activated partial thromboplastin time, and platelet count) were collected at 5 points of time for 72 h. TIC was diagnosed if any three readings were abnormal during this period. Patients were also followed up posthospital discharge using the Glasgow Outcome Score (GOS) at 1 and 3 months. Statistical Analysis: Data were analyzed using SPSS ver. 21. Logistic regression analysis was employed to determine individual coagulation test as best predictors for mortality. P < 0.05 was considered statistically significant. Results: The incidence of TIC was found to be 62%; it was 63.75% in severe head injury and 55% in moderate head injury patients. Deranged INR at the time of hospital admission (odds ratio [OR] 4.38) and PTI at 24 h (OR 3.913) are highly predictive of mortality. There was no significant difference in GOS score at 1 and 3 months. Conclusions: The incidence of TIC in our study was 62% among iTBI patients. It contributes to increased mortality at 1 and 3 months. However, the neurological outcome was not different in between the groups. [ABSTRACT FROM AUTHOR]

Constructing a robust hybrid material with a porous inorganic and a porous organic framework is highly intriguing owing to its diverse functionality and porosity. However, the line of synthesis is not straightforward, since their nucleation and crystal growth processes are incompatible. Here, a simple method for the fabrication of hybrid zeolite/metal–organic framework of different framework structures is developed wherein the less‐useful extra‐framework aluminum species present in the zeolite surrogate the growth of metal organic framework (MOF) from the zeolite matrix in the presence of organic linkers of the corresponding MOF. An NMR study confirms that all the octahedral Al species are converted to Al‐MOF. TGA analysis shows that 32 % Al of H‐Beta is converted to Al‐MOF. Furthermore, NH3 TPD analysis shows that most of the weak acid sites disappear but strong acid sites are preserved suggesting the utilization of weakly bound Al species of H‐Beta in the growth of Al‐MOF. The synthesis strategy is successfully demonstrated using H‐Beta, H‐ZSM‐5, and H‐Y zeolites for the growth of MIL‐53 and MIL‐96 MOFs from the zeolite matrix. This synthesis strategy enables application‐based engineering of the framework structures, functionality, and porosity of the materials. [ABSTRACT FROM AUTHOR]

A (1-(4-bromobenzyl)-1H-1,2,3-triazole-4-yl)methyl(4-bromophenyl)carbamate and (1-(4-methylbenzyl)-1H-1,2,3-triazole-4-yl)methyl(4-bromophenyl)carbamates (4a-4b) have been successfully synthesized by reacting prop-2-yn-1-yl(4-bromophenyl)carbamate (2) with 4-bromo benzyl bromide (3a) and 4-methyl benzyl bromide (3b) using cellulose supported cuprous iodide nanoparticles and water as solvent. These synthesized triazoles were utilized for the stabilization of silver nanoparticles. The triazole stabilized silver nanoparticles were further examined for their ion sensing ability towards various cations like, Hg2+, Cd2+, Cu2+, Zn2+, Pb2+, Cr2+, Co2+, Fe2+, Ni2+, Ca2+, Mg2+ and Mn2+ ions. The colorimetric and UV-visible studies revealed that stabilized AgNPs selectively sense Hg2+ ion in preferences to other cations. Transmission electron microscopy (TEM) images clearly indicated that addition of Hg2+ to a solution of stabilized AgNPs triggered the aggregation of silver nanoparticles due to which there occurs change in color from dark orange to colorless. The detection limits of AgNPs stabilized by 4a and 4b for Hg2+ ions was found to be 4.1×10-6 M and 3.67×10-7 M, respectively. The present paper provides an easy and selective colorimetric approach for detection of mercury ion. [ABSTRACT FROM AUTHOR]

Abstract The molecular, electronic and crystal structures of tetramethyltetraselenafulvalene (TMTSF) have been investigated. The experimental IR and Raman spectra and single crystal XRD for TMTSF have been interpreted. In order to facilitate this, computations have been carried out for the molecular structures and vibrational characteristics of the TMTSF molecule. Study of Molecular electrostatic potential surface of the TMTSF and its cation is also done. Normal mode assignments have been made on the basis of the computed potential energy distributions (PEDs). In addition, a comprehensive study of molecular geometries, atomic charges and vibrational fundamentals of TMTSF and its cationic molecule has been carried out. Vibronic coupling constants in TMTSF and TMTSF+ have been computed using the DFT/B3LYP results. The TMTSF molecule belongs to C 2v point group symmetry. All the studied molecules exhibit partial double bond character as all the bond lengths are changed from their usual bond lengths. The partial double bond character has been found to be indicate that the conducting behaviour of these molecules. In the unit cell of TMTSF, some H atoms and all the Se atoms are interacting with the molecules of neighboring and its own cell. The major changes in frequencies from neutral to the cationic state for í (ring) and í(C C) are found for the both molecules. The vibronic coupling corresponding to a vibrational mode helps to transport charge along the stacks of a conducting organic molecules from a neutral molecule to an adjacent charged ion. The magnitude of the VCC is noticed to be maximum for the í (C C). The geometry of the neutral molecule under this mode resembles to that of the ion and vice-versa. The large VCC of this mode shows that removal of an electron is much easier during the vibrational modes. Thus from the present study i.e. the molecular, electronic and crystal structures and vibronic investigations confirm the conducting behaviour of the TMTSF molecule. From the MEP surface it is clear that the sites close to selenium atoms in TMTSF show region of most negative electrostatic potential. Graphical abstract Image 1 Highlights • Tetramethyltetraselenafulvalene (TMTSF) has non-planar structure with C 2v symmetry. • Crystal structure pattern shows that all the four Se atoms and the four H atoms (H 6 , H 9 , H 12 and H 18) of the TMTSF molecule interact. • Conductivity of TMTSF has been investigated with the help of VCCs. • The vibrational modes v (C CH 3), v (ring) have participated in the vibronic coupling with good contribution. • The molecular, electronic and crystal structures and vibronic investigations confirm the conducting behaviour of the TMTSF molecule. [ABSTRACT FROM AUTHOR]

The voice of a person plays an important role in analyzing people. From voice of the person we not only recognize the gender of the person but also detect the emotion of the person. Gender recognition and emotion detection both has its importance in forensics, games, in security purposes and of course in our day to day life. This paper proposes a system that allows recognizing a person's emotional state starting from audio signal registrations. Identifying the gender and emotion of a speaker from speech has a variety of applications ranging from speech analytics to personalizing human-machine interactions. While gender identification in previous works has explored the use of the statistical properties of the speaker's pitch features, in this project, we explore the impact of using acoustic features on identifying gender. In addition to gender we will also predict the emotion of speaker using the same acoustic values. We present a novel approach that models acoustic properties in the interest of identifying the speaker's gender and emotion with as little speech as possible. In this project we will investigate two datasets containing voice samples of over 3000 people for gender and over 1000 voice samples for emotions. [ABSTRACT FROM AUTHOR]

[Display omitted] A convenient, eco-friendly, organobase-catalyzed one-pot two-step sequential approach to a fascinating class of various 4-(3-arylquinoxalin-2-ylmethyl)-substituted sulfamidates in good to high yields is reported. This C C/C N bond-forming reaction proceeds via a Mannich reaction of cyclic N -sulfonyl aldimines with 1-aryl-2-alkyl-1,2-diketones catalyzed by triethylamine, followed by the aza-cyclization of in situ formed 1,2-dicarbonyl precursors with ortho -diaminoarenes in PEG-400 as a natural, reusable, and benign solvent at room temperature. In addition, this 100% carbon atom-economic approach could be viable for gram-scale synthesis and tolerates various synthetically resourceful functionalities under mild conditions. [ABSTRACT FROM AUTHOR]

The present article discusses the typical influence of grafted conducting polymers in the mesoscale pores of dielectric particles on the static and dynamic electrorheology and electro-viscoelastic behavior of corresponding colloids. Nanocrystalline meso-nanoporous zeolite has been prepared by chemical synthesis and subsequently polyaniline (PANI) coating has been implemented. Electrorheological (ER) suspensions have been formed by dispersing the nanoparticles in silicone oil and their viscoelastic behaviors are examined to understand the nature of such complex colloidal systems under electric fields. PANI-Zeolite ER fluids demonstrate higher static electroviscous effects and yield stress potential than untreated Zeolite, typically studied in literature. Transient electro-viscous characterizations show a stable and negligible hysteresis behavior when both the fluids are exposed to constant as well as time varying electric field intensities. Further oscillatory shear experiments of frequency and strain sweeps exhibit predominant elastic behavior in case of Zeolite based ER suspensions as compared to PANI systems. Detailed investigations reveal Zeolite based ER suspensions display enhanced relative yielding as well as electro-viscoelastic stability than the PANI-Zeolite. The steady state viscous behaviors are scaled against the non-dimensional Mason number to model the system behavior for both fluids. Experimental data of flow behaviors of both the ER fluids are compared with semi-classical models and it is found that the CCJ model possesses a closer proximity than traditional Bingham model, thereby revealing the fluids to be generic pseudo-linear fluids. The present article reveals that while the PANI based fluids are typically hailed superior in literature, it is only restricted to steady shear utilities. In case of dynamic and oscillatory systems, the traditional Zeolite based fluids exhibit superior ER caliber. [ABSTRACT FROM AUTHOR]

Current study details about the impact of solid state fermentation and subsequent extrusion on the physicochemical, sensory and bioactive properties of the rice-black gram dough. Influence of the solid-state fermentation was evaluated, at three levels of yeast concentration (1–3%), sugar (4–8%) and fermentation time (2–6 h). Fermentation resulted in decreased pH and residual sugar, from 6.38 to 5.41 and 1.07 to 0.69%, respectively, whereas the titratable acidity was increased from 0.86 to 1.79%, after 6 h of fermentation. Moreover, solid state fermentation for 6 h leads to increased total phenolic content, antioxidant activity and protein content from 29.80 to 44.12 mg GAE/100 g, 3.38–5.10 mg GAE/100 g and 10.36–13.65%, respectively. FTIR analysis showed decreased crystallinity up on fermentation. Subsequently, dough fermented for 6 h with 3% yeast and 4% sugar (optimized condition) was considered for the extrusion processing, which leads to increased phenolic content and antioxidant activity up to 77.3 mg GAE/100 g, and 11.39 mg GAE/100 g, respectively. Expansion ratio, bulk density, water solubility and water absorption index were determined for product characterization. Furthermore, extrudate prepared from the fermented flour had slightly higher acceptability (mean score: 4.12) than the unfermented counter part (mean score: 3.75) out of 5. [ABSTRACT FROM AUTHOR]

In this study, zirconium, zinc, and copper-based metal organic framework catalysts were synthesized. In order to tune the catalytic activity, the coordinative unsaturated metal–organic frameworks were functionalized with different amines by an economical and simple post-synthetic modification strategy. In this study, systematic investigation is made by the functionalization of metal organic frameworks with primary, secondary, and tertiary amines by the post-synthesis method. Furthermore, the metal organic frameworks were also functionalized with one basic ionic liquid. The materials were characterized by powder X-ray diffraction, nitrogen adsorption, scanning electron microscopy, thermo gravimetric analysis, Fourier transform infrared, X-ray photoelectron spectroscopy, and temperature programmed desorption techniques. The applications of these bi-functional catalysts were investigated in the best suited model reaction, Knoevenagel condensation. The applicability of these catalysts was extended in the synthesis of jasminaldehyde (aldol condensation of 1-heptanal and benzaldehyde) and cyclic carbonate (cycloaddition of CO2 to epoxide). The catalysts can be easily recovered and reused with negligible loss in the catalytic activity even after five cycles. [ABSTRACT FROM AUTHOR]

There is another advantage is that the proper catheter placement can be ensured, by injecting saline through the catheter with still the needle in situ. In such continuous set, the catheter can be advanced immediately after the bolus dose or it can be done simultaneously along with bolus administration once the space has opened up and the remaining drug will be administered without disturbing the catheter. [Extracted from the article]

Cu nanoparticles decorated metal organic framework was successfully synthesized and investigated in the eco-friendly and sustainable synthesis of indolizine and chalcone using phenyl acetylene as one of the building block. [Display omitted] • Cu-MOF based recyclable heterogeneous catalysts were prepared. • To enhance the catalytic activity, CuNPs decorated Cu-MOF was prepared. • Multi-component reaction was carried out using phenylacetylene as a building block. • Phenylacetylene and 2-pyridinecarboxaldehyde were reacted to prepare chalcone. • Base and solvent play critical role in the synthesis of indolizine and chalcone. Cu based metal organic frameworks were prepared and investigated as heterogeneous catalysts in the multi-component coupling reaction involving phenylacetylene as one of the building block for the synthesis of indolizine. Using the same set of reactants, chalcone was synthesized in neat condition. To enhance the catalytic activity and selectivity, Cu nanoparticles decorated Cu based metal organic framework was prepared using NaBH 4 as reducing agent and sodium dodecyl sulfate as capping agent. Materials were characterized by the complementary combination of X-ray diffraction, N 2 -adsorption, scanning/transmission electron microscopic technique, Fourier transform infrared spectroscopy, UV–vis spectroscopy, X-ray photoelectron spectroscopy, and electrochemical method. For comparative purpose, Cu cluster compound and CuO were also prepared. Recycling and leaching experiments were performed to demonstrate the sustainability and robustness of the catalytic system. A wide range of indolizine and chalcones were prepared in high yields using this catalyst. [ABSTRACT FROM AUTHOR]

A series of Cu based ionic liquids was synthesized by the reaction of 1-butyl-3-methylimidazolium salts and copper(ii) salts. These ionic liquids were investigated as catalysts in the synthesis of amides (primary, secondary and tertiary amides). For easy separation and recycling, the Cu based ionic liquids were decorated on nanocrystalline silicalite. The materials were characterized using powder X-ray diffraction, nitrogen adsorption, scanning and transmission electron microscopy, thermogravimetric analysis, and nuclear magnetic resonance, Fourier transform infrared and UV-visible spectroscopy. The Cu based ionic liquids decorated on nanocrystalline silicalite were found to be efficient and recyclable catalysts for the amide synthesis. The catalysts were found to be stable and show negligible loss of the activity even after five cycles. [ABSTRACT FROM AUTHOR]

The present study was conducted on the thoracic vertebrae of Blue bull. Twelve or thirteen thoracic vertebrae were characterized by long supraspinous processes which increased in height and breadth up to the fourth vertebra and then gradually decreased upto last. The bodies were short, distinctly constricted in the middle and were expanded at the extremities. The transverse processes were short, thick and single. Each transverse process possessed a tubercular facet on its ventral aspect for articulation with tubercle of the rib. Its backward inclination increased up to the sixth and then subsequently decreased upto last. In the last thoracic vertebra, the body was oval and the posterior pair of costal facets was absent and the spine was vertical. [ABSTRACT FROM AUTHOR]

The present study had been conducted on the lumbar vertebrae of blue bull. There were six lumbar vertebrae. The transverse processes were spreading out laterally and slightly bent forward. The length of the first transverse process was the shortest and straight, which gradually increased up to the last. The width of last two processes was less than the same of first four vertebrae. The height of spinous process decreased gradually from first to the last. The mammillary processes of lumbar vertebrae were fused with the anterior articular processes, which were thick and tuberous. In the last lumbar vertebra, the body was compressed from above downwards and the neural ring was widest. The articular processes were placed wide apart from body. The interarcuate spaces were gradually increased from the fourth-fifth lumbar and sixth lumbar-sacrum vertebra. [ABSTRACT FROM AUTHOR]

Insertion of fins and turbulators is one of the effective approaches to augment the restricted heat transfer characteristics of an air-based flat plate solar collector and the creation of holes/perforations in baffles and fins further increase the degree of improvement. Therefore, the prime objective of the present study is the experimental assessment of temperature distribution, heat transfer coefficients and thermal efficiency of a solar air heater integrated with baffles and fins in the form of hollow semicircular loops. The plain absorber plate was modified with the continuous insertion of semicircular loops of 0.03 m radius, constructed with wire of 0.002 m thick in a staggered manner. The experiments were conducted for measurement of solar intensity and collector temperature at air mass flow rates ranging from 0.006 to 0.02 kg/s. Results indicated the temperature of the air to be lower than loops and absorber plate but surpassed the glass plate temperature. The average temperature rise of air in finned collector was ranging from 14.08 to 22.78 °C, remarkably higher than conventional flat plate solar collector. Air mass flow rate of 0.02 kg/s presented 109%, 80.72% and 62.56% augmented average heat transfer coefficient than 0.006, 0.01 and 0.015 kg/s, respectively and 22.03% enhanced thermal efficiency than 0.006 kg/s. Further, the finned collector at 0.02 kg/s yielded 19.73–34.3% superior average thermal efficiency and 37.38–66.05% escalated heat transfer coefficient over the smooth absorber plate solar collector. The solar collector with hollow fins and baffles will be suitable for domestic and industrial applications like agricultural products drying, greenhouse, and space heating. [Display omitted] • Experimental study on semicircular loop solar collector was performed. • An air temperature rise of 14.08–22.78 °C was observed in finned solar collector. • Air mixing and heat dissipation from absorber plate to air was improved with fins. • Incorporation of fins and baffles increased the thermal efficiency by 19.73–34.3%. • Higher air mass flow rate provided superior thermal performance of the collector. [ABSTRACT FROM AUTHOR]

A novel, dual template mediated, one-step direct synthesis route is reported here for the preparation of nanocrystalline zeolites of different framework structures (such as ZSM-5, mordenite, and sodalite). In this synthesis strategy, a suitably designed dicationic/tetra-cationic soft template was used along with a conventional zeolite structure director to obtain nanocrystalline zeolites with nanosheet morphology. Nanocrystalline zeolites exhibited large surface area, pore volume, and intercrystalline mesopores. The long hydrophobic chain containing a multiammonium template cooperatively participates in the zeolite crystallization process along with a conventional microporous zeolite structure director to form the ultrathin microporous zeolite framework, while the hydrophobic interaction between the long chains restricted the excessive growth of zeolites and induced the formation of intercrystalline mesopores. Nanocrystalline zeolites exhibited exceptionally high activity in the acid-catalyzed reactions involving large molecules when compared with conventional zeolites. This synthesis strategy can be extended for the preparation of zeolites of different framework structures or other porous materials in the future. [ABSTRACT FROM AUTHOR]

We report the impact of silver addition on granularity of NdFeAsO 0.8 F 0.2 superconductor. The ac susceptibility and electrical resistivity under magnetic field are measured to study the improvement in weak links of NdFeAsO 0.8 F 0.2 with addition of Ag x ( x = 0.0–0.3). The Ag free NdFeAsO 0.8 F 0.2 compound shows superconductivity at around 51.8 K. Typical two step superconducting transitions due to the inter- and intra-grain contributions, induced from the combined effect of superconducting grains and the inter-granular weak-coupled medium respectively are clearly seen in susceptibility [ χ ( T )] plots. In comparison to the pure NdFeAsO 0.8 F 0.2 compound, the coupling between the superconducting grains is significantly improved for 20 at% silver doped sample, and the same is deteriorated for higher Ag content i.e., for 30 at%Ag sample. The magneto transport measurements ρ ( T ) H of polycrystalline 20 at% Ag doped NdFeAsO 0.8 F 0.2 exhibited the upper critical filed [ H c2 (0)] of up to 334 T, which is slightly higher than the one observed for pure NdFeAsO 0.8 F 0.2 . The flux flow activation energy ( U 0 / k B ) varies from 7143.38 K to 454.77 K with magnetic field ranging from 0 T to 14 T for 20 at% Ag doped NdFeAsO 0.8 F 0.2 . In this investigation, our results show that limited addition of Ag improves the granular coupling of superconducting grains of NdFeAsO 0.8 F 0.2 compound. [ABSTRACT FROM AUTHOR]

The Cu(I)-catalyzed 1,3-dipolar cycloaddition between terminal alkynes and organic azides generating 1,4-disubstituted 1,2,3-triazoles has attracted considerable attention owing to its consistency, specificity, and biocompatibility. Copper nanoparticles supported on various supports such as agarose, cellulose, chitosan, charcoal, activated carbon, silica gel, aminoclay, polymer support like poly(styrene-co-maleimide) (SMI) and polyvinylpyrrolidone (PVP) have been utilized as heterogeneous catalyst for the synthesis of 1,2,3-triazoles. This review summarizes various straightforward and efficient methods for the regioselective synthesis of 1,4-disubstituted 1,2,3-triazoles utilizing supported copper nanoparticles as a source of the heterogeneous catalytic species and water as solvent. [ABSTRACT FROM AUTHOR]

Molecular geometries and vibrational spectra for the ground state of 2,3-dichloro-5,6-dicyno-p-benzoquinone ( DDQ ) and its anion ( DDQ − ) were computed using DFT method at the B3LYP level employing 6-311++G(d,p) basis set whereas for the first excited state ( DDQ ∗ ), these were calculated using TD-DFT at the B3LYP level employing the 6-311++G(d,p) basis set available with the Gaussian 09 package. The spectra have been experimentally investigated and the observed IR and Raman bands have been assigned to different normal modes on the basis of the calculated potential energy distributions (PEDs). XRD of single crystal has been investigated to determine molecular and crystal structures of DDQ. In order to elucidate the transfer of electrons, electronic structure and electronic absorption have been calculated with the TD-DFT method. Vibronic interaction and its role in the appearance of superconductivity in the DDQ, DDQ − and DDQ ∗ molecules have been investigated. The present XRD, molecular, electronic and vibronic studies indicate that mainly the a g C O stretching and ring stretching modes participate in the charge transfer process. [ABSTRACT FROM AUTHOR]

DABCO (1,4-diazabicyclo[2.2.2]octane) based Cu(I) metal organic framework (here after represented as Cu(I)-MOF) catalyzed Sonogashira cross-coupling reaction of iodobenzene and phenylacetylene was conducted smoothly to afford diphenylacetylene in excellent yield under N 2 atmosphere. For comparative study, piperidine based Cu(I) clusters were also investigated. Among these catalysts, Cu(I)-MOF exhibited higher activity with good selectivity for the C–C cross-coupled product. Cu(I) catalysts investigated in this study exhibited similar activity in the C–C homo-coupling reaction of phenylacetylene in O 2 atmosphere. Application of these catalysts was extended in the C–N coupling reactions between phenylboronic acid and aromatic/aliphatic/heterocyclic amines. Cu(I)-MOF can be readily recovered from the reaction mixture and reused for several cycles without loss in the catalytic activity. [ABSTRACT FROM AUTHOR]

Abstract: We report the synthesis and physical property characterization of PrFe1−x Co x AsO (x=0.0–1.0). The studied samples are synthesized by through the solid state reaction route via the vacuum encapsulation method. The pristine compound PrFeAsO does not show superconductivity, but rather exhibits a metallic step like transition due to spin density wave (SDW) ordering of Fe moments (FeSDW) below 150K, followed by another upward step due to anomalous ordering of Pr moments (PrTN) at 12K. Both the FeSDW and PrTN temperatures decrease monotonically with Co substitution at Fe site. Superconductivity appears in a narrow range of x from 0.07 to 0.25 with maximum T c at 11.12K for x=0.15. Samples with x≥0.25 exhibit metallic behavior right from 300K down to 2K, without any FeSDW or PrTN steps in resistivity. In fact, though FeSDW decreases monotonically, the PrTN disappeared even with x=0.02. The magneto transport measurements below 14T on superconducting polycrystalline Co doped PrFeAsO lead to extrapolated values of the upper critical fields [H c2(0)] of up to 60T. [Copyright &y& Elsevier]

Highlights: [•] YBCO: Ag x composites. [•] High field magneto-transport. [•] The upper critical field. [ABSTRACT FROM AUTHOR]

In this letter, we present the superconducting property characterization of a phase pure, reasonably good quality YBaCuO sample. Studied compound is crystallized in orthorhombic Pmmm space group with lattice parameters a, b, and c being 3.829(2), 3.887(1) and 11.666(3) Å, respectively. Bulk superconductivity is observed below 90 K as evidenced by resistivity and dc/ ac magnetization measurements. The resistivity under magnetic field ( ρTH) measurements showed clearly both the intra-grain and inter-grain transitions, which are supplemented by detailed (of varying frequency and amplitude) ac susceptibility studies as well. The upper critical field at 0 K, i.e. H(0) being determined from ρTH measurements with 50 % criteria of resistivity drop, is ∼70 T. Studied polycrystalline YBaCuO is subjected to detailed heat capacity ( C) studies. C exhibited well-defined anomaly at below 90 K, which decreases with applied field. Although the C anomaly/peak at T reduces with applied field, the same is not completely suppressed in high applied fields of up to 12 T. The Sommerfeld constant ( γ) and Debye temperature ( Θ), as determined from low temperature fitting of C( T) data to Sommerfeld-Debye model, are 10.65 mJ/mole-K and 312.3 K, respectively. The results are compared with existing literature on bulk polycrystalline superconducting YBaCuO sample. [ABSTRACT FROM AUTHOR]

We report the effect of silver addition on superconducting performance of bulk YBCO (YBaCuO) superconductor. All the studied samples are prepared by conventional solid-state reaction method. Rietveld fitted X-ray diffraction data confirmed the single phase formation for all the studied samples. Detailed AC susceptibility measurements as a function of driven AC amplitude (1 Oe-17 Oe) of these samples revealed the enhancement of grains coupling with increasing Ag content in YBCO + Ag composite system. 10 wt% Ag added YBCO superconductors exhibited the optimal intergranular coupling. The Scanning Electron Microscopy (SEM) observations indicate an increase in the grains connectivity in terms of narrow grain boundaries for doped samples. The average grain size is found to increase with Ag doping. It is concluded that limited addition of Ag in bulk YBCO superconductor significantly improves the grains coupling and, as a result, the optimal superconducting performance. YBCO + Ag composites could prove to be potential candidates for bulk superconducting applications of the studied high- T system. [ABSTRACT FROM AUTHOR]