Facile preparation and characterization of biodegradable and biocompatible UV shielding transdermal patches based on natural rubber latex- dextrin blends.

The physico-chemical and biological properties of natural rubber latex (NRL), entailing its biodegradability and biocompatibility, render it a promising material for various biomedical applications. This research explores the facile blending of NRL with dextrin in different compositions to investigate its potential as a prospective UV shielding transdermal patch for biomedical applications. The superior compatibility between the polymers after blending and the improved thermal stability have been established through FTIR, DSC, and TGA examinations, respectively. Optimization of blended polymers for compatibility, wettability, crystallinity, and static mechanical properties has been performed. Morphology characterization conducted via SEM and AFM techniques suggests a uniform morphology for the optimized blend system. The UV shielding ability of the blend has been confirmed by the evaluation of in-vitro UV shielding performance, UV protection factor (UPF), and the superior protection of the optimized system on living cells upon UV irradiation. The observed cell viability, swelling, erosion, porosity, hemocompatibility, and soil degradation properties suggest the NRL-DXT combination for the possible development of high-quality transdermal patches.

Coherent Control of the Fine-Structure Qubit in a Single Alkaline-Earth Atom.

We report on the first realization of a novel neutral atom qubit encoded in the spin-orbit coupled metastable states ^{3}P_{0} and ^{3}P_{2} of a single ^{88}Sr atom trapped in an optical tweezer. Raman coupling of the qubit states promises rapid single-qubit rotations on par with the fast Rydberg-mediated two-body gates. We demonstrate preparation, readout, and coherent control of the qubit. In addition to driving Rabi oscillations bridging an energy gap of more than 17 THz using a pair of phase-locked clock lasers, we also carry out Ramsey spectroscopy to extract the transverse qubit coherence time T_{2}. When the tweezer is tuned into magic trapping conditions, which is achieved in our setup by tuning the tensor polarizability of the ^{3}P_{2} state via an external control magnetic field, we measure T_{2}=1.2 ms. A microscopic quantum mechanical model is used to simulate our experiments including dominant noise sources. We identify the main constraints limiting the observed coherence time and project improvements to our system in the immediate future. Our Letter opens the door for a so-far-unexplored qubit encoding concept for neutral atom-based quantum computing.

Long distance optical transport of ultracold atoms: A compact setup using a Moiré lens.

We present a compact and robust setup to optically transport ultracold atoms over long distances. Using a focus-tunable moiré lens that has recently appeared in the market, we demonstrate transport of up to a distance of 465 mm. A transfer efficiency of 70% is achieved with a negligible temperature change at 11 µK. With its high thermal stability and low astigmatism, the moiré lens is superior to fluid-based varifocal lenses. It is much more compact and stable than a lens mounted on a linear translation stage, allowing for simplified experimental setups.

Matrix-filler interactions and solvent sorption features of nanohydroxyapatite (nHA) embedded ethylene-co-vinyl acetate (EVA)-millable polyurethane (MPU) blends.

We report the solvent sorption features and matrix filler interactions of nanohydroxyapatite (nHA) embedded ethylene-co-vinyl acetate (EVA)-millable polyurethane (MPU) blends, using toluene, xylene, and t-butylacetate as probe molecules. The EVA/MPU blends were initially loaded with different quantities of n-HA, and the interfacial interactions were evaluated through FTIR and XRD techniques. The modulation of solvent resistance was subsequently examined in terms of filler loading, temperature and molar volume of the probes. With an increase in the amount of nHA, the solvent resistance of the matrix has been found to be enhanced, with the mechanism of transport regularly deviating from the conventional Fickian mode normally followed by elastomer matrices. The Flory-Rehner equation was employed to compute the molecular mass between crosslinks (Mc) and the crosslink density (γ). The observed enhancement in the crosslink density and the degree of reinforcement has been attributed to the increased polar-polar interactions after nHA loading into the matrix. The experimentally obtained values of Mc have been compared with phantom and affine models, to identify the type of deformation happening under solvent stress. The reinforcement effect within the matrix, as a function of filler loading, has been verified by using the Kraus equation. The swelling resistance of the composites has also been verified in biological fluids in view of the possible biofield applications of the composites.

Indolocarbazole based polymer coated super adsorbent polyurethane sponges for oil/organic solvent removal.

The synthesis of an indolocarbazole-fluorene based conjugated polymer (ICZP6), by Sonogashira coupling reaction, has been presented. The ICZP6 has then been integrated with a nano iron oxide embedded polyurethane foam (ICZP6PUF) to develop a promising adsorbent for oil/organic contaminants in aqueous systems. The anchoring ability of ICZP6 on to iron oxide PU sponge switches on significant hydrophobicity within the whole molecular assembly. The cooperative effects of ICZP6-iron oxide- PU sponge system have been highlighted in terms of structural, microscopic and wettability characteristics. The heterogeneity and hierarchical porous structure of the system offer a high adsorption capability for different types of oils and organic contaminants in water, typically in the range of 100-240 gg-1. The performance of ICZP6PUF has been confirmed by the fast (within 5-10s) and choosy removal of selected oils and organic solvents from polluted water with the aid of an external magnetic field. The adsorbed materials (oil/organic solvents) can be separated from the adsorbent by simple mechanical squeezing without causing any structural deformation or performance deterioration; with a reusability of the system over 50 cycles. The adsorption isotherm has been found to fit well with the Langmuir model with R2 = 0.9484. To extent the scope of the ICZP6PUF hybrid, an integrative logic gate has been designed.

Trabecular microstructure is influenced by race and sex in Black and White young adults.

Lower fracture rates in Black men and women compared to their White counterparts are incompletely understood. High-resolution imaging specific to trabecular bone may provide insight. Black participants have enhanced trabecular morphology. These differences may contribute to the lower fracture risk in Black versus White individuals. INTRODUCTION: Lower fracture rates in Black men and women compared to their White counterparts may be explained by favorable bone microstructure in Black individuals. Individual trabecular segmentation (ITS) analysis, which characterizes the alignment and plate- and rod-like nature of trabecular bone using high-resolution peripheral quantitative computed tomography (HR-pQCT), may provide insight into trabecular differences by race/ethnic origin. PURPOSE: We determined differences in trabecular bone microarchitecture, connectivity, and alignment according to race/ethnic origin and sex in young adults. METHODS: We analyzed HR-pQCT scans of 184 adult (24.2 ± 3.4 years) women (n = 51 Black, n = 50 White) and men (n = 34 Black, n = 49 White). We used ANCOVA to compare bone outcomes, and adjusted for age, height, and weight. RESULTS: Overall, the effect of race on bone outcomes did not differ by sex, and the effect of sex on bone outcomes did not differ by race. After adjusting for covariates, Black participants and men of both races had greater trabecular plate volume fraction, plate thickness, plate number density, plate surface area, and greater axial alignment of trabeculae, leading to higher trabecular bone stiffness compared to White participants and women, respectively (p < 0.05 for all). CONCLUSION: These findings demonstrate that more favorable bone microarchitecture in Black individuals compared to White individuals and in men compared to women is not unique to the cortical bone compartment. Enhanced plate-like morphology and greater trabecular axial alignment, established in young adulthood, may contribute to the improved bone strength and lower fracture risk in Black versus White individuals and in men compared to women.

Polyvinyl alcohol/carboxymethyl cellulose/ZSM-5 zeolite biocomposite membranes for dye adsorption applications.

In this work, efficient biodegradable membranes were fabricated using polyvinyl alcohol (PVA), carboxymethyl cellulose (CMC) and ZSM-5 zeolite, and their utility for the removal of a cationic dye, methylene blue (MB), was investigated. The physical properties of the membranes were assessed by FTIR, XRD, UTM, SEM, optical microscopy and thermogravimetry. The influence of various parameters viz., zeolite loading, initial dye concentration, temperature and contact time on the dye removal capability of the membranes was investigated. The results show that the adsorption capacity of the membranes increases with an increase in zeolite content and initial dye concentration, while an elevated temperature decreases the adsorption capacity. A high dye removal efficiency (97%) and high adsorption capacity (7.83) were observed for 5 wt% of zeolite loaded sample for an initial dye concentration of 10 ppm with a contact time of 10 h at 30 °C. The equilibrium adsorption data were analysed using Langmuir and Freundlich models. The regression results showed that the equilibrium adsorption data were more accurately described by the Freundlich model (R2 = 0.998) rather than the Langmuir adsorption isotherm (R2 = 0.961), suggesting heterogeneous adsorption. The adsorption kinetic results show that the pseudo second order model (R2 = 0.996) is the suitable model to describe the kinetic behavior of MB onto PVA/CMC/ZSM-5 zeolite membranes.The present study suggests that the PVA/CMC/ZSM-5 zeolite membranes are suitable candidates for the efficient removal of methylene blue, from aqueous streams.

Assessment of the Effectiveness of Combat Eyewear Protection Against Blast Overpressure.

It is unclear whether combat eyewear used by U. S. Service members is protective against blast overpressures (BOPs) caused by explosive devices. Here, we investigated the mechanisms by which BOP bypasses eyewear and increases eye surface pressure. We performed experiments and developed three-dimensional (3D) finite element (FE) models of a head form (HF) equipped with an advanced combat helmet (ACH) and with no eyewear, spectacles, or goggles in a shock tube at three BOPs and five head orientations relative to the blast wave. Overall, we observed good agreement between experimental and computational results, with average discrepancies in impulse and peak-pressure values of less than 15% over 90 comparisons. In the absence of eyewear and depending on the head orientation, we identified three mechanisms that contributed to pressure loading on the eyes. Eyewear was most effective at 0 deg orientation, with pressure attenuation ranging from 50 (spectacles) to 80% (goggles) of the peak pressures observed in the no-eyewear configuration. Spectacles and goggles were considerably less effective when we rotated the HF in the counter-clockwise direction around the superior-inferior axis of the head. Surprisingly, at certain orientations, spectacles yielded higher maximum pressures (80%) and goggles yielded larger impulses (150%) than those observed without eyewear. The findings from this study will aid in the design of eyewear that provides better protection against BOP.

Live donor liver transplantation for antitubercular drug-induced acute liver failure.

Antitubercular therapy (ATT)-induced hepatotoxicity is often over looked and active tuberculosis is considered a contraindication for liver transplantation, however it might be the only lifesaving option to certain patients of acute liver failure (ALF) due to ATT. We have assessed the outcome of live donor liver transplantation in ATT-induced ALF. A retrospective analysis of all the cases of ALF that underwent liver transplantation from 2006 to 2014 at the Amrita Institute of Medical Sciences was done. A total of seven (7.7%) patients with ATT-induced ALF who had underwent live donor liver transplantation were included in the study. Out of seven patients, three (42.8%) had established diagnosis of tuberculosis and the remaining (58.2%) patients were started on ATT empirically. The median duration of ATT intake was 2 months. All the patients underwent live donor liver transplant as they met King's College criteria, and their model for end-stage liver disease score was above 35 on admission, receiving graft from first degree relatives. Histopathology of explant liver showed pan acinar necrosis. Restarting of ATT after transplant was individualized. It was restarted only in two (28%) patients with prior sputum-positive pulmonary tuberculosis after a median time of 27 days after transplant. ATT was not restarted in rest of the (72%) patients. Postoperative mortality was seen in two (28%) patients due to conditions that masquerade the ATT-induced acute liver failure. The overall survival rate was 71.4% with a median follow up of 22 months. Live donor-related transplantation is feasible option in ATT-induced acute liver failure. Restarting of ATT post liver transplant is feasible and should be individualized along with frequent monitoring of immunosuppressant levels; however, if the primary diagnosis of tuberculosis was empirical, reintroduction of ATT can be omitted.

Gastrointestinal intramural hematoma--analysis of clinical and radiological features for early differentiation from mesenteric ischemia.

INTRODUCTION: Long-term anticoagulation is associated with hemorrhage at various sites. Gastrointestinal intramural bleeds and hematomas (IMH) often mimic mesenteric ischemia (MI) due to similar clinical settings and imaging features, making early differentiation difficult. AIM: To compare the demography, clinical features and imaging characteristics of patients presenting with IMH with those of MI, so as to help in evolving clinical and imaging guidelines to differentiate both early in the course of the disease. METHODS: All radiologically (contrast-enhanced computed tomogram [CT]) diagnosed cases of gastrointestinal IMH from the hospital database during the period between 2006 and 2012 were retrospectively analyzed. This data was compared with the clinical and imaging features of a group of surgically confirmed MI during the same period. Patients not on anticoagulation therapy at the time of presentation and those with incomplete clinical or radiological data were excluded from the study. RESULTS: There were 16 patients in IMH group and 54 patients in MI group. Clinical features like overt rectal bleeding or melena, and prolonged prothrombin time-international normalized ratio (PT-INR) more than three, and CT features like proximal location in the bowel, increased bowel wall thickness, hyperdensity on plain scan (>40 Hounsfield units (HU)), and short segment bowel involvement were significantly associated with IMH. Visualization of embolus and absent mesenteric vasculature to a segment of intestine in CT was significantly associated with MI. CONCLUSION: Attention to clinical features and early CT scan can aid in early differentiation of IMH from MI, facilitating appropriate intervention early in the course of disease.

Finite element model for nutrient distribution analysis of a hollow fiber membrane bioreactor.

Hollow fiber membrane bioreactors (HFMB) are extensively used for the development of tissue substitutes for bones and cartilages. In an HFMB, the nutrient transport is dependent on the material properties of the porous scaffold and fiber membrane and also on the fluid flow through the hollow fiber. The difficulty in obtaining real-time data along with the presence of large number of variables in experimental studies have lead to increased application of computational models for the performance analysis of bioreactors. A major difficulty in the computational analysis of HFMB is the modeling of the interactions at the fluid and porous scaffold interfaces, which has often been neglected or incorporated using specific boundary conditions. In this study, a new FEM is developed to analyze the fluid flow in the fluid-porous region with the interface coupled directly into the FEM. Distribution of nutrients in the bioreactor is studied by coupling mass transport equations to the fluid-porous finite element framework. The new model is implemented to study the influence of permeability, cell density, and flow rate on the nutrient concentration distribution in the HFMB. The developed computational framework is an ideal tool to study fluid flow through porous-open channels and can also be used for the design of bioreactors for optimal tissue growth.

Cost and efficacy of immunosuppression using generic products following living donor liver transplantation in India.

BACKGROUND: Cost of post liver transplant immunosuppression is a major financial burden to patients in developing countries. In India, generic varieties of various immunosuppressants are often used without any definite evidence to their efficacy. This study was aimed at studying the dosage, side effect profile and cost of post-liver transplant immunosuppression using generic products in Indian population following living donor liver transplantation (LDLT). METHODS: Data on dose, cost, and toxicity of immunosuppression were retrieved retrospectively from case records of 59 patients who had undergone LDLT at our center. RESULTS: Adequate immunosuppression was obtained by tacrolimus (Pangraf(®)-Panacea) of 0.04 to 0.05 mg/Kg, and mycophenolate (Mycept(®)-Panacea) of 500 to 1,000 mg; the acute rejection rate was 15% during the first month. Serum tacrolimus levels were 5.4 to 7.3 ng/mL. The cost of immunosuppression varied from Rs. 28,705 in the first month to Rs. 8,820 per month at the end of first year, amounting to an average monthly cost of Rs. 17,250. Approximately 23% and 51% of cost was for mycophenolate and for drug level measurement of tacrolimus, respectively. CONCLUSION: Average cost of immunosuppression after LDLT in India is much lower than that reported elsewhere in the world, since lower drug doses are needed and cheaper generic drugs are available. This can be reduced further by decreasing the frequency of tacrolimus drug level measurement.

Adsorption and removal kinetics of phosphonate from water using natural adsorbents.

The removal of phosphonate from water was studied using some natural adsorbents. Potassium phosphonate is a fungicide used for the control of Phytophthora capsici, which is prevalent in black pepper (Piper nigrum L.). Batch adsorption kinetic experiments were conducted on the adsorption of phosphonate onto the adsorbents. The concentration of phosphonate was measured on a high-performance liquid chromatograph fitted with a conductivity detector. The percentage removal of phosphonate by powdered laterite stone (PLS) from water was 40.4%, within a residence time of 15 minutes. The mechanisms of the rate of adsorption were analyzed and compared using the pseudo-second-order, Elovich, and intraparticle diffusion models. The experimental data was found to correlate well with the pseudo-second-order kinetic model, indicating adsorption as a chemisorption process. A possible reaction in the phosphonate-PLS system also has been proposed. The PLS can be used as a low-cost natural adsorbent for phosphonate removal from water.

Tissue-fluid interface analysis using biphasic finite element method.

Numerical studies on fluid-structure interaction have primarily relied on decoupling the solid and fluid sub-domains with the interactions treated as external boundary conditions on the individual sub-domains. The finite element applications for the fluid-structure interactions can be divided into iterative algorithms and sequential algorithms. In this paper, a new computational methodology for the analysis of tissue-fluid interaction problems is presented. The whole computational domain is treated as a single biphasic continuum, and the same space and time discretisation is carried out for the sub-domains using a penalty-based finite element model. This procedure does not require the explicit modelling of additional boundary conditions or interface elements. The developed biphasic interface finite element model is used in analysing blood flow through normal and stenotic arteries. The increase in fluid flow velocity when passing through a stenosed artery and the drop in pressure at the region are captured using this method.

Constitutive material modeling of cell: a micromechanics approach.

The variations in mechanical properties of cells obtained from experimental and theoretical studies can be overcome only through the development of a sound mathematical framework correlating the derived mechanical property with the cellular structure. Such a formulation accounting for the inhomogeneity of the cytoplasm due to stress fibers and actin cortex is developed in this work. The proposed model is developed using the Mori-Tanaka method of homogenization by treating the cell as a fiber-reinforced composite medium satisfying the continuum hypothesis. The validation of the constitutive model using finite element analysis on atomic force microscopy (AFM) and magnetic twisting cytometry (MTC) has been carried out and is found to yield good correlation with reported experimental results. It is observed from the study that as the volume fraction of the stress fiber increases, the stiffness of the cell increases and it alters the force displacement behavior for the AFM and MTC experiments. Through this model, we have also been able to find the stress fiber as a likely cause of the differences in the derived mechanical property from the AFM and MTC experiments. The correlation of the mechanical behavior of the cell with the cell composition, as obtained through this study, is an important observation in cell mechanics.