Bulk and Interfacial Effects on Density in Polymer Nanocomposites

The barrier properties of polymers are a significant factor in determining the shelf or device lifetime in polymer packaging. Nanocomposites developed from the dispersion of nanometer thick platelets into a host polymer matrix have shown much promise. The magnitude of the benefit on permeability has been different depending on the polymer investigated or the degree of dispersion of the platelet in the polymer. In this dissertation, the effect of density changes in the bulk and at the polymer-platelet interface on permeability of polymer nanocomposites is investigated. Nanocomposites of nylon, PET, and PEN were processed by extrusion. Montmorillonite layered silicate (MLS) in a range of concentrations from 1 to 5% was blended with all three resins. Dispersion of the MLS in the matrix was investigated by using one or a combination of X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Variation in bulk density via crystallization was analyzed using differential scanning calorimetry (DSC) and polarized optical microscopy. Interfacial densification was investigated using force modulation atomic force microscopy (AFM) and ellipsometry. Mechanical properties are reported. Permeability of all films was measured in an in-house built permeability measurement system. The effect of polymer orientation and induced defects on permeability was investigated using biaxially stretched, small and large cycle fatigue samples of PET and nylon nanocomposites. The effect of annealing in nylon and nanocomposites was also investigated. The measured permeability was compared to predicted permeability by considering the MLS as an ideal dispersion and the matrix as a system with concentration dependent crystallinity

Modeling Sub-Band Information Through Discrete Wavelet Transform to Improve Intelligibility Assessment of Dysarthric Speech

The speech signal within a sub-band varies at a fine level depending on the type, and level of dysarthria. The Mel-frequency filterbank used in the computation process of cepstral coefficients smoothed out this fine level information in the higher frequency regions due to the larger bandwidth of filters. To capture the sub-band information, in this paper, four-level discrete wavelet transform (DWT) decomposition is firstly performed to decompose the input speech signal into approximation and detail coefficients, respectively, at each level. For a particular input speech signal, five speech signals representing different sub-bands are then reconstructed using inverse DWT (IDWT). The log filterbank energies are computed by analyzing the short-term discrete Fourier transform magnitude spectra of each reconstructed speech using a 30-channel Mel-filterbank. For each analysis frame, the log filterbank energies obtained across all reconstructed speech signals are pooled together, and discrete cosine transform is performed to represent the cepstral feature, here termed as discrete wavelet transform reconstructed (DWTR)- Mel frequency cepstral coefficient (MFCC). The i-vector based dysarthric level assessment system developed on the universal access speech corpus shows that the proposed DTWRMFCC feature outperforms the conventional MFCC and several other cepstral features reported for a similar task. The usages of DWTR- MFCC improve the detection accuracy rate (DAR) of the dysarthric level assessment system in the text and the speaker-independent test case to 60.094 % from 56.646 % MFCC baseline. Further analysis of the confusion matrices shows that confusion among different dysarthric classes is quite different for MFCC and DWTR-MFCC features. Motivated by this observation, a two-stage classification approach employing discriminating power of both kinds of features is proposed to improve the overall performance of the developed dysarthric level assessment system. The two-stage classification scheme further improves the DAR to 65.813 % in the text and speaker- independent test case

Internal stress in Cat-CVD microcrystalline Si:H thin films

Stress in the Cat-CVD μc-Si:H films is of concern for the performance of the flexible solar cells and MEMS devices. We report the results of our initial studies on stress determination of the HWCVD deposited μc-Si:H films and its variation with thermal treatment. From the analysis of the stress values of the intrinsic μc-Si:H films it is seen (at least in the preliminary results obtained) that films deposited around 250 °C show a lower stress which could be due to the better network and optimum hydrogen content in the films. Secondly the doped films show an order of magnitude larger internal stress compared to the intrinsic films while the grain size is comparable. However upon annealing the stress minimizes and we get films with very low stress.© Elsevie

A comparative study of postoperative acidemia after intraoperative administration of balanced crystalloid (Plasma-lyte A@) versus 0.9% sodium chloride in gastrointestinal surgery

Background: The administration of intravenous fluids is one of the most common and universal interventions in medicine. Fluid therapy is the most challenging and debated aspect of perioperative care. Plasma-lyte A® Injection (multiple electrolytes injection, type 1, USP) is indicated as a source of water and electrolytes or as an alkalinizing agent. 0.9% sodium chloride is an isotonic crystalloid solution having a sodium concentration higher is useful in replacing fluid and electrolyte loss. Aims and Objectives: The study was designed to compare the effects of intraoperative administration of balanced crystalloid solution (Plasma-Lyte A®) and 0.9% NaCl on acid-base balance in the post-operative period in patients undergoing gastrointestinal surgery. Materials and Methods: Eighty consenting patients of ASA-l and ASA-II who underwent Gastrointestinal surgery were at first randomly allocated to 2 groups. One group received Plasma-Lyte A® as the sole crystalloid and the other group received 0.9% sodium chloride. Results: Serum Na+ conc. of the groups were comparable and no difference was shown at the time of induction, but postoperatively at 12 h, there was a significant increase in group 2. There was no significant difference in serum K+ concentration in both the groups except at 6 h postoperatively when there was an increase in K+ concentration in group 1. Serum Cl− concentration was having no significant difference at the time of induction and 1 h intraoperative, but postoperatively at 1, 6, and 12 h the Cl− concentration significantly increased in group 2. HCO3− concentration of the two groups had no difference between them throughout the study period. The pH of patients in both the groups showed no statistically significant difference during the entire procedure (P>0.05). A significant decrease in pH observed in 0.9% sodium chloride group in comparison to Plasma-Lyte® group when the duration of surgery increased to more than 120 min. Conclusion: Both plasma-lyte A and 0.9% sodium chloride can be used safely as intravenous infusion fluid without altering pH status and blood electrolyte concentration in patients undergoing gastrointestinal surgery

Evaluation of F1 Crosses of Brinjal (Solanum melongena L.) Landraces for Fruit Yield, Quality and Tolerance to Bacterial Wilt

Field experiment was carried out at All India Coordinated Research Project on Vegetable Crops, OUAT, Bhubaneswar, Odisha, India in order to identify the superior F1 crosses for marketable fruit yield quality and resistance to bacterial wilt. All total 21 F1 crosses evolved from seven distinctly diverse local landraces of brinjal along with a hybrid check, Mahy Green were evaluated by adopting Randomized Block Design and replicated twice in rabi 2021-2022. Results revealed significant variations among various fruit quality attributes (TSS: 4.32 oBrix to 6.00 oBrix and ascorbic acid content of fruit: 5.10 mg100g-1 to 7.10 mg100g-1), incidence of bacterial wilt (30 DAT: 0.00% to 4.17%, 60 DAT: 0.00% to 12.50% and 90 DAT: 0.00% to 20.83%). Out of 21 crosses, nine cross showed immune reaction to bacterial wilt at 90 DAT. The marketable fruit yield plant-1 varied significantly from 1.00 kg to 1.99 kg. The F1 cross viz. BBSR-08-2 × Selection from BBSR-145-1(1.99 kg) recorded significantly highest fruit yield plant-1 followed by BBSR-08-2 × BBSR-10-25(1.87 kg) and BBSR-08-2 × BBSR-10-26 (1.81 kg). Thus, it may be concluded that, F1 crosses obtained from local landraces of brinjal viz., BBSR-08-2 × Selection from BBSR-145-1, BBSR-08-2 × BBSR-10-25 and BBSR-08-2 × BBSR-10-26 may be recommended for higher marketable fruit yield, fruit quality and over all resistance to bacterial wilt for higher profit. These local landraces may also be used for future brinjal improvement programme towards development varieties with higher fruit yield quality and resistance to bacterial wilt

Survey implementation process and interviewer effects on skipping sequence of maternal and child health indicators from National Family Health Survey: An application of cross-classified multilevel model

Implementing a large-scale survey involves a string of intricate procedures exposed to numerous types of survey errors. Uniform and systematic training protocols, comprehensive survey manuals, and multilayer supervision during survey implementation help reduce survey errors, providing a consistent fieldwork environment that should not result in any variation in the quality of data collected across interviewers and teams. With this background, the present study attempts to delineate the effect of field investigator (FI) teams and survey implementation design on the selected outcomes. Data on four of the bigger Empowered Action Group (EAG) states of India, namely Uttar Pradesh, Madhya Pradesh, Bihar, and Rajasthan, were obtained from the fourth round of the National Family Health Survey (NFHS-4) for analysis. A fixed-effect binary logistic regression model was used to assess the effect of FI teams and survey implementation design on the selected outcomes. To study the variation in the outcome variables at the interviewer level, a cross-classified multilevel model was used. Since one interviewer had worked in more than one primary sampling unit (PSU) & district and did not follow a perfect hierarchical structure, the cross-classified multilevel model was deemed suitable. In addition, since NFHS-4 used a two-stage stratified sampling design, two-level weights were adjusted for the models to compute unbiased estimates. This study demonstrated the presence of interviewer-level variation in the selected outcomes at both inter- and intra-field agencies across the selected states. The interviewer-level intra-class correlation coefficient (ICC) for women who had not availed antenatal care (ANC) was the highest for eastern Madhya Pradesh (0.23) and central Uttar Pradesh (0.20). For ‘immunisation card not seen’, Rajasthan (0.16) and western Uttar Pradesh (0.13) had higher interviewer-level ICC. Interviewer-level variations were insignificant for women who gave birth at home across all regions of Uttar Pradesh. Eastern Madhya Pradesh, Rajasthan, and Bihar showed higher interviewer-level variation across the selected outcomes, underlining the critical role of agencies and skilled interviewers in different survey implementation designs. The analysis highlights non-uniform adherence to survey protocols, which implies that not all interviewers and agencies performed in a similar manner in the field. This study recommends a refined mechanism for field implementation and supervision, including focused training on the challenges faced by FIs, random vigilance, and morale building. In addition, examining interviewer-level characteristics, field challenges, and field agency effects may also highlight the roots of interviewer-level variation in the data. However, based on the interviewer\u27s performance in the field, the present study offers an intriguing insight into interviewer-level variations in the quality of data

Quality of anthropometric data in India\u27s National Family Health Survey: Disentangling interviewer and area effect using a cross-classified multilevel model

India has adopted a target-based approach to reduce the scourge of child malnourishment. Because the monitoring and evaluation required by this approach relies primarily on large-scale data, a data quality assessment is essential. As field teams are the primary mode of data collection in large-scale surveys, this study attempts to understand their contribution to variations in child anthropometric measures. This research can help disentangle the confounding effects of regions/districts and field teams on the quality of child anthropometric data. The anthropometric z-scores of 2,25,002 children below five years were obtained from the fourth round of India\u27s National Family and Health Survey (NFHS-4), 2015–16. Unadjusted and adjusted standard deviations (SD) of the anthropometric measures were estimated to assess the variations in measurements. In addition, a cross-classified multilevel model (CCMM) approach was adopted to estimate the contribution of geographical regions/districts and teams to variations in anthropometric measures. The unadjusted SDs of the measures of stunting, wasting, and underweight were 1.7, 1.4, and 1.2, respectively. The SD of stunting was above the World Health Organisation threshold (0.8–1.2), as well as the Demographic and Health Survey mark. After adjusting for team-level characteristics, the SDs of all three measures reduced marginally, indicating that team-level workload had a marginal but significant role in explaining the variations in anthropometric z-scores. The CCMM showed that the maximum contribution to variations in anthropometric z-scores came from community-level (Primary Sampling Unit (PSU)) characteristics. Team-level characteristics had a higher contribution to variations in anthropometric z-scores than district-level attributes. Variations in measurement were higher for child height than weight. The present study decomposes the effects of district- and team-level factors and highlights the nuances of introducing teams as a level of analysis in multilevel modelling. Population size, density, and terrain variations between PSUs should be considered when allocating field teams in large-scale surveys

Highly conducting doped poly-Si deposited by hot wire CVD and its applicability as gate material for CMOS devices

Highly conducting p- and n-type poly-Si:H films were deposited by hot wire chemical vapor deposition (HWCVD) using SiH4+H2+B2H6 and SiH4+H2+PH3 gas mixtures, respectively. Conductivity of 1.2×102 (Ω cm)−1 for the p-type films and 2.25×102 (Ω cm)−1 for the n-type films was obtained. These are the highest values obtained so far by this technique. The increase in conductivity with substrate temperature (Ts) is attributed to the increase in grain size as reflected in the atomic force microscopy results. Interestingly conductivity of n-type films is higher than the p-type films deposited at the same Ts. To test the applicability of these films as gate contact Al/poly-Si/SiO2/Si capacitor structures with oxide thickness of 4 nm were fabricated on n-type c-Si wafers. Sputter etching of the poly-Si was optimized in order to fabricate the devices. The performance of the HWCVD poly-Si as gate material was monitored using C–V measurements on a MOS test device at different frequencies. The results reveal that as deposited poly-Si without annealing shows low series resistance.© Elsevie

An emerging natural antioxidant therapy for COVID‐19 infection patients: Current and future directions

Abstract Severe acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2) affects millions of people worldwide. The article aims to review the therapeutic perspective on natural antioxidants, their mechanism of action, pharmacokinetics in management and cure of COVID‐19/ SARS‐CoV‐2 infection. We conducted a literature search including World Health Organization and National Institute of Health guidelines and clinical trials registered with ClinicalTrials.gov limited to antioxidants in COVID‐19 management. Elderly, immunocompromised patients, and others with underlying health conditions or multiple comorbidities have a high mortality rate. Disrupted redox homeostasis and oxidative stress seem to be biological pathways that may increase personal vulnerability to infection. Antioxidants like vitamins C, D, E, epigallocatechin‐3 gallate, and morin have been reported to protect against COVID‐19 disease. Reactive oxygen species are immunological regulatory elements of viral replication. Natural antioxidants exhibit potential action in preventing inflammation and organ dysfunction during viral infection. They also increase glutathione level, oxygenation rate, and immunological responses in the treatment of sepsis and acute respiratory distress syndrome. No wonder the selection of prevention, treatment, and cure of COVID‐19 and SARS‐CoV‐2 mainly depends upon the antiviral and immunoregulatory activity which they possess. Yet, their efficacy against COVID‐19 is of great concern and demands extensive study