An all phosphorene lattice nanometric spin valve.

Phosphorene is a unique semiconducting two-dimensional platform for enabling spintronic devices integrated with phosphorene nanoelectronics. Here, we have designed an all phosphorene lattice lateral spin valve device, conceived via patterned magnetic substituted atoms of 3d-block elements at both ends of a phosphorene nanoribbon acting as ferromagnetic electrodes in the spin valve. Through First-principles based calculations, we have extensively studied the spin-dependent transport characteristics of the new spin valve structures. Systematic exploration of the magnetoresistance (MR) of the spin valve for various substitutional atoms and bias voltage resulted in a phase diagram offering a colossal MR for V and Cr-substitutional atoms. Such MR can be directly attributed to their specific electronic structure, which can be further tuned by a gate voltage, for electric field controlled spin valves. The spin-dependent transport characteristics here reveal new features such as negative conductance oscillation and switching of the sign of MR due to change in the majority spin carrier type. Our study creates possibilities for the design of nanometric spin valves, which could enable integration of memory and logic elements for all phosphorene 2D processors.

Comparative Efficacy and Safety of Amlodipine and Losartan Potassium in Essential Hypertension in a Tertiary Hospital of Bangladesh.

Hypertension is a common disorder of major clinical, public health and economic importance. It affects men and women of all ages, and the prevalence is increasing in most countries. Maintenance of blood pressure below 140/90 mm of Hg is recommended by most of the guideline available around the world. Various classes of drugs are being used in the treatment of hypertension. Losartan potassium and amlodipine are two different antihypertensive agents belonging to two different groups used commonly around the world in treating essential hypertension. Losartan potassium is non-peptide Angiotensin-II receptor antagonist. Amlodipine which is the third generation dihydropyridine group of calcium channel blocker. The aim of the study was to compare the efficacy and safety of amlodipine and losartan for the treatment of essential hypertensive patients (18-75 years). A non-randomized comparative observational study was conducted in the Department of Pharmacology and Therapeutics in collaboration with Department of Medicine, Sylhet, MAG Osmani Medical College, Sylhet, Bangladesh from July 2021 to June 2022. In this study non-randomization was in two groups. Group A received amlodipine 5mg daily at morning and Group B received losartan potassium 50mg daily at night. The study parameters were systolic blood pressure (SBP), diastolic blood pressure (DBP), ankle oedema, serum K+ level. The result of treatment outcome was compared between two groups. After treatment the reduction of SBP was 5.19±2.93mm of Hg versus 3.27±1.34mm of Hg (p<0.001); reduction of DBP was 1.7±0.70 mm of Hg versus 0.68 mm of Hg (p<0.001) and serum K+ level 4.22±0.27mmol/L versus 4.21±0.16mmol/L (p<0.719) in amlodipine and losartan group respectively. Amlodipine is more effective than losartan potassium in respect to treatment of essential hypertension. Regarding adverse events losartan potassium causes angioedema, hyperkalemia, headache, dizziness etc. The study concluded that amlodipine is superior to losartan potassium in treating essential hypertension.

Quench dynamics of edge states in a finite extended Su-Schrieffer-Heeger system.

We examine the quench dynamics of an extended Su-Schrieffer-Heeger (SSH) model involving long-range hopping that can hold multiple topological phases. Using winding number diagrams to characterize the system's topological phases geometrically, it is shown that there can be multiple winding number transition paths for a quench between two topological phases. The dependence of the quench dynamics is studied in terms of the survival probability of the fermionic edge modes and postquench transport. For two quench paths between two topological regimes with the same initial and final topological phase, the survival probability of edge states is shown to be strongly dependent on the winding number transition path. This dependence is explained using energy band diagrams corresponding to the paths. Following this, the effect of the winding number transition path on transport is investigated. We find that the velocities of maximum transport channels varied along the winding number transition path. This variation depends on the path we choose, i.e., it increases or decreases depending upon the path. An analysis of the coefficient maps, energy spectrum, and spatial structure of the edge states of the final quench Hamiltonian provides an understanding of the path-dependent velocity variation phenomenon.

Identification and classification of arrhythmic heartbeats from electrocardiogram signals using feature induced optimal extreme gradient boosting algorithm.

Arrhythmic heartbeat classification has gained a lot of attention to accelerate the detection of cardiovascular diseases and mitigating the potential cause of one-third of deaths worldwide. In this article, a computer-aided diagnostic (CAD) approach has been proposed for the automated identification and classification of arrhythmic heartbeats from electrocardiogram (ECG) signals using multiple features aided supervised learning model. For proper diagnosis of arrhythmic heartbeats, MIT-BIH Arrhythmia database has been used to train and test the proposed approach. The ECG signals, extracted from sensor leads, have undergone pre-processing via discrete wavelet transform. Three sets of features, i.e. statistical, temporal, and spectral, are extracted from the processed ECG signals followed by random forest aided recursive feature elimination strategy to select the prominent features for proper classification of arrhythmic heartbeats by the proposed optimal extreme gradient boosting (O-XGBoost) classifier. Hyperparameters such as learning rate, tree-specific parameters, and regularization parameters have been optimized to improve the performance of the XGBoost classifier. Moreover, the synthetic minority over-sampling technique has been employed for balancing the dataset in order to improve the classification performance. Quantitative results reveal the remarkable performance over state-of-the-art methods. The proposed model can be implemented in any computer-aided diagnostic system with similar topological structures.

Spontaneous Formation of Star-Shaped Surface Patterns in a Driven Bose-Einstein Condensate.

We observe experimentally the spontaneous formation of star-shaped surface patterns in driven Bose-Einstein condensates. Two-dimensional star-shaped patterns with l-fold symmetry, ranging from quadrupole (l=2) to heptagon modes (l=7), are parametrically excited by modulating the scattering length near the Feshbach resonance. An effective Mathieu equation and Floquet analysis are utilized, relating the instability conditions to the dispersion of the surface modes in a trapped superfluid. Identifying the resonant frequencies of the patterns, we precisely measure the dispersion relation of the collective excitations. The oscillation amplitude of the surface excitations increases exponentially during the modulation. We find that only the l=6 mode is unstable due to its emergent coupling with the dipole motion of the cloud. Our experimental results are in excellent agreement with the mean-field framework. Our work opens a new pathway for generating higher-lying collective excitations with applications, such as the probing of exotic properties of quantum fluids and providing a generation mechanism of quantum turbulence.

Dextran based amphiphilic nano-hybrid hydrogel system incorporated with curcumin and cerium oxide nanoparticles for wound healing.

During injury or diseased condition, wound dressing fails to properly integrate or repair the tissue and restore its function due to various factors like poor bioavailability, systemic delivery of hydrophobic drugs and elevated levels of reactive oxygen species. Here, we fabricated a novel nano-hybrid hydrogel system, based-on gelatin and oxidized dextran, embedded with nano-formulation of curcumin and cerium oxide, dispersed by physical interaction within the hydrogel. The curcumin was entrapped in amphiphilic alkylated-dextran nanoparticles to enhance its bioavailability and release at the injured site while cerium oxide nanoparticles were used without any additional processing. The hydrogel was characterized for various properties and demonstrated a controlled and prolonged drug release (∼63 % in 108 h), accelerated cell migration besides providing a highly significant antioxidant and in-vivo anti-inflammatory activity (∼39 %). The preliminary study suggests that this hybrid system can significantly promote wound healing and the potential to become an ideal wound dressing.

High efficiency spin filtering in magnetic phosphorene.

Phosphorene has a unique set of characteristics such as a semiconducting nature, good carrier mobility and low-spin orbit coupling aspects which makes it a highly prospective two dimensional material for cross-hybrid architectures in nanoelectronics, spintronics, and optoelectronics. In the spintronic context, the creation of a stable magnetic order in phosphorene can be immensely beneficial for designing phosphorene spin circuits. In this work, we present high efficiency spin filtering behaviour in magnetically rendered phosphorene. First, we calculate the effect of doping various 3d block elements in phosphorene to introduce a stable magnetic order. Next, by varying doping concentrations in distinct doping configurations, an extensive phase diagram has been obtained depicting the presence of various electronic and magnetic states. This allows us to achieve a high magnetisation in the presence of various transition metal atoms, with a spin polarisation of ∼100% in half-metallic regimes. The transport behaviour reveals a map of the spin injection efficiency showing enhancement with doping concentration and reaching a perfect spin filtering capacity of ∼100% in the presence of Ti, Cr, Mn, Co, and Fe atoms. The present results offer new insights into engineered designs of multi-functional phosphorene spintronic circuits.

Green synthesis of near-infrared absorbing eugenate capped iron oxide nanoparticles for photothermal application.

Nanomaterials exhibit different interesting physical, chemical, electronic and magnetic properties that can be used in a variety of biomedical applications such as molecular imaging, cancer therapy, biosensing, and targeted drug delivery. Among various types of nanoparticles, super paramagnetic iron oxide nanoparticles (SPIONs) have emerged as exogenous contrast agents for in vitro and in vivo deep tissue imaging. Here, we propose a facile, rapid, non-toxic, and cost-effective single step green synthesis method to fabricate eugenate (4-allyl-2-methoxyphenolate) capped iron oxide nanoparticles (E-capped IONPs). The magnetic E-capped IONPs are first time synthesized using a medicinal aromatic plant, Pimenta dioica. The Pimenta dioica leaf extract was used as a natural reducing agent for E-capped IONPs synthesis. The crystalline structure and size of the synthesized spherical nanoparticles were confirmed using the x-ray diffraction and electron microscopic images respectively. In addition, the presence of the functional groups, responsible for capping and stabilizing the synthesized nanoparticles, were identified by the Fourier transform infra-red spectrum. These nanoparticles were found to be safe for human cervical cancer (HeLa) and human embryonic kidney 293 (HEK 293) cell lines and their safety was established using MTT[3-(4, 5-Dimethylthiazol-2-yl)-2, 5-Diphenyltetrazolium Bromide] assay. These green synthesized E-capped IONPs display a distinct absorbance in the tissue transparent near-infrared (NIR) wavelength region. This property was used for the NIR photothermal application of E-capped IONPs. The results suggest that these E-capped IONPs could be used for deep tissue photothermal therapy along with its application as an exogenous contrast agent in biomedical imaging.

Carbon mineralization in soil as influenced by crop residue type and placement in an Alfisols of Northwest India.

Carbon (C) mineralization of crop residues is an important process occurring in soil which is helpful in predicting CO2 emission to the atmosphere and nutrient availability to plants. A laboratory experiment was conducted in which C mineralization of residues of rice (Oryza sativa), wheat (Triticum aestivum), maize (Zea mays), mungbean (Vigna radiata) and their mixtures was applied to the soil surface or incorporated into an Alfisols from Northwest India. C mineralization was significantly affected by residue placement and type and their interactions. Rice residue had a higher decomposition rate (k = 0.121 and 0.076 day-1) than wheat (0.073 and 0.042 day-1) and maize residues (0.041 day-1) irrespective of placements. Higher decomposition rates of rice and wheat were observed when placed on soil surface than incorporated in the soils. Additive effects of the contribution of each residue type to C mineralization of the residue mixture were observed. When mungbean residue was added to the rice/wheat or maize/wheat mixture, decomposition of the residue mixture was enhanced. Crop residues with low N and high C/N ratio such as maize, wheat, rice and their mixtures can be applied on the soil surface for faster C and N mineralization, thereby helping to manage high volumes of residues under conservation agriculture-based practices in northwest India.

A hedgehog pathway-dependent gene signature is associated with poor clinical outcomes in Luminal A breast cancer.

PURPOSE: High expression of glioma-associated oncogene homolog-1 (GLI1) is associated with poor prognosis in estrogen receptor (ER) positive breast cancers. We sought to define a GLI1-dependent gene signature in ER-positive tumors that could further stratify patients at higher risk for disease recurrence and potentially lead to novel combination therapies. METHODS: We identified an inverse correlation between GLI1 expression and distant disease-free survival (DFS) using a dataset developed at MD Anderson Cancer Center (Hatzis dataset) containing clinical data from 508 breast cancer patients. Using a qPCR-based microarray platform, we identified genes differentially regulated by GLI1 in MCF7 cells and then determined if expression of these genes correlated with GLI1 expression in patient tumor samples. Statistical comparison between the groups was performed by ANOVA. Direct comparison of two groups was done by a two-tailed t test. Correlations between variables were done by Pearson's method. RESULTS: Expression of GLI1 and its target genes correlated significantly with worse distant DFS in breast cancer patients with Luminal A molecular subtype. Particularly, co-expression of GLI1 with EGFR and/or SNAI1, two of the identified GLI1 targets, was predictive of worse distant DFS in this subtype. Furthermore, patients with Luminal A tumors with a high GLI1 signature had a shorter distant DFS compared to the Luminal B subtype and the outcome for this group was comparable to patients with HER2-positive or basal-like tumors. CONCLUSION: We have identified a novel GLI1 gene signature that is associated with worse clinical outcomes among the patients with Luminal A subtype of breast cancer.

Development of a gold-nano particle based novel dot immunobinding assay for rapid and sensitive detection of Banana bunchy top virus.

An improved gold nanoparticle based Dot immunobinding assay (DIBA) was developed for the detection of Banana bunchy top virus (BBTV), that is more efficient, sensitive, rapid and simpler than conventional DIBA and ELISA. Instead of enzyme conjugates, gold nanoparticles were used as reporters owing to their unique optical properties. Antibody was raised against expressed recombinant coat protein of BBTV. The gold nanoparticles were conjugated to primary / detection antibody raised following immunization with recombinant coat protein, making it highly specific for the virus. Gold nanoparticle conjugated primary antibody (GCPab) based DIBA developed in this study has a detection efficiency comparable to ELISA. The results of using this assay format for detection of BBTV in banana plants from four geographical regions of India are also presented in this report. The test could detect the virus at sap dilution up-to 10-2. Using this improved DIBA, any lab with basic amenities can perform indexing on large numbers of samples.

Influence of green grass-based diets on growth and reproductive performance in dairy heifers.

The objective of this study was to monitor the changes in growth, dry matter intake, and blood profiles (nutrition and reproductive hormones) of dairy heifers in response to green grass-based diets. Twelve crossbred heifers were equally divided into group 1: rice straw and concentrate; group 2: rice straw, green grass, and concentrate; group 3: green grass and concentrate; group 4: green grass, soybean hay, and concentrate. Dry matter intake in group 4 was found 6% higher (P < 0.05) than group 1. Negative body weight gain was found in group 1 and group 2 showed 14% higher body weight gain per 30 days compared to groups 3 and 4 (P < 0.05). Heifers in group 4 had significantly (P < 0.05) higher heart girth gain, serum albumin, urea, and blood urea nitrogen than the heifers in other groups. Endocrine parameters were found similar among groups. Overall, supply of green grass especially a mix of leguminous and non-leguminous was found advantageous in heifer feeding.

Molecular identification of tick-borne pathogens infecting cattle in Mymensingh district of Bangladesh reveals emerging species of Anaplasma and Babesia.

Tick-borne diseases are considered a major hindrance to the health and productive performance of cattle in Bangladesh. To elucidate the epidemiology of tick-borne pathogens (TBPs) in local cattle, a cross-sectional study was performed in the 12 subdistricts (Upazilas) of Mymensingh district in Bangladesh. Blood samples and ticks were collected from 384 clinically healthy cattle kept by 135 farmers from 96 randomly selected villages. DNA extracted from the blood samples was subsequently screened by polymerase chain reaction (PCR) and a Reverse Line Blot (RLB) hybridization assay using an in-house prepared chemiluminescence solution for the presence of Anaplasma, Ehrlichia, Rickettsia, Babesia and Theileria spp. A total of 2,287 ticks were collected from 232 infested cattle (60.4%, 232/384) and identified morphologically as Rhipicephalus (Boophilus) microplus (n = 1,432, 62.6%) and Haemaphysalis bispinosa (n = 855; 37.4%). The RLB results demonstrated that the majority of the cattle (62.2%) were infected with at least one TBP. Theileria orientalis infections were most common (212/384, 55.2%) followed by infections with Anaplasma bovis (137/384, 35.67%), Anaplasma marginale (16/384, 4.17%), Babesia bigemina (4/384, 1.04%) and Babesia bovis (2/384, 0.52%). A previously uncharacterized Anaplasma sp. (Anaplasma sp. Mymensingh) and Babesia sp. (Babesia sp. Mymensingh), which are genetically closely related to Anaplasma platys and B. bigemina, were detected in 50 of 384 (13.0%) and 1 of 384 (0.3%) of the blood samples, respectively. Key risk factors for the occurrence of T. orientalis, A. marginale and Anaplasma sp. Mymensingh were identified. In conclusion, this study revealed that cattle in Mymensingh district are mainly infested with R. microplus and H. bispinosa ticks and may carry multiple TBPs. In addition, two previously uncharacterized pathogens were detected in the bovine blood samples. The pathogenicity of these species remains to be determined.

Modeling the sensing characteristics of chemi-resistive thin film semi-conducting gas sensors.

For chemi-resistive thin film gas sensors a generic theoretical model is proposed to predict the variation of sensor response with the operating temperature and thickness of the sensing film. A diffusion equation is formulated assuming that inflammable target gases move through the sensing film by Knudsen diffusion and react with the adsorbed oxygen following first-order kinetics. We have assumed a realistic non-linear variation between the conductance and test gas concentration and derived a general expression relating the sensor response to the operating temperature and thickness of the film. Assuming Langmuir adsorption kinetics, we have theoretically predicted the response and recovery transients during gas sensing using thin film sensing elements. It is predicted that for irreversible type sensing, the response time is reduced with an increase in test gas concentration, whereas for reversible sensing, the response time is independent of test gas concentration. For zinc oxide thin film sensors, an excellent match is obtained between the model prediction and experimental data for their thickness (122 nm to 380 nm) and temperature variation (200 °C to 325 °C) in 500 ppm carbon monoxide (CO) sensing. The maximum CO response% (∼53%) was achieved in 320 nm thick ZnO films. The conductance transients for response and recovery for CO sensing closely follow Langmuir adsorption kinetics and as predicted theoretically, indeed for irreversible sensing, the response time reduces from 350 s to 220 s with an increase in test gas concentration from 20 to 550 ppm. In the case of reversible sensing we found that the response time is ∼55 s irrespective of the CO gas concentration in the range of 5-500 ppm. The models developed in the present work are quite generic in nature and we have discussed their applicability to a wide variety of sensing materials with various types of surface morphologies.

Necrotising fasciitis after laparoscopic rectal cancer surgery.

Necrotising fasciitis is a rare, serious infection of the deep fascia leading to subcutaneous tissue necrosis. It is extremely important for this condition to be identified and treated promptly as it bears significant mortality. We describe a case of necrotising fasciitis after laparoscopic rectal cancer surgery. To our knowledge, this is the first case reported after the specific procedure. This case report aims to encourage surgeons to have a low threshold in recognising necrotising fasciitis postoperatively, especially for patients with possible risk factors.

Neurodevelopmental Outcomes in Children Born to Climate Refugee Mothers in Bangladesh: Experiences from Cyclone Aila.

Cyclone Aila hit the South-West coast of Bangladesh in May 2009, when in Dacope Upazilla over 50,000 people were left homeless as climate refugees (CRs) for over two years. We determined neurodevelopmental status of children born as CRs compared to their non-Climate Refugee (NCR) counterparts. Pregnant mothers were enrolled from May 2009 to April 2010 in entire Dacope in a study which profiled their health conditions. From among these mothers, 12 months post-Aila 267 CR mother-child dyads, and 552 NCR mother-child dyads were enrolled to assess their children's neurodevelopmental outcomes. There were significantly more landless families among CRs compared to NCRs (p value = 0.0001; OR = 1.86, 95% CI: 1.37 - 2.51). The mean±SD age at assessment of CR children was 8.52±4.57 months compared to a mean age 9.09±4.13 months of the NCR children (p=0.610). Neurodevelopmental Impairments (NDIs) were three times higher in the former (21.3%), compared to the latter (7.4%) group (p=0.0001; OR 3.83, 95% CI: 2.16 - 5.21). Specifically, expressive language (p value 0.002; OR 2.86, 95% CI: 1.46 - 5.57) and gross motor functions (p=0.007; OR 2.27, 95% CI 1.22 - 4.20) were the most significantly affected areas of impairment. Children born to CR mothers had a three times higher proportion of NDIs. The findings are of concern as in Bangladesh large populations are forced to leave their homes and become CRs annually. Optimum antenatal care of pregnant women as well as their offsprings within refugee situations needs to be ensured to prevent NDIs and poor quality of survival.

A comparative study on the structural, optical and magnetic properties of Fe3O4 and Fe3O4@SiO2 core-shell microspheres along with an assessment of their potentiality as electrochemical double layer capacitors.

Herein, we report a comprehensive and comparative study on the crystal structure, and microstructural, optical, magnetic, hyperfine and electrochemical properties of Fe3O4 microspheres (S1) of diameter ∼418 nm and Fe3O4@SiO2 core-shell microspheres (S2) of diameter ∼570 nm. Each asymmetric unit of the crystalline Fe3O4 has one cation vacancy at the octahedral [B] site. At 300 K the saturation magnetization and coercivity of ferrimagnetically ordered S1 and S2 are 63.5, 38.5 emu g(-1) and 200 and 120 Oe, respectively. We have shown that the synthesis procedure, morphology, surface properties, interparticle interaction manifesting the collective properties of the nanoparticle assembly and the average size of individual Fe3O4 nanoparticles forming the spherical ensemble play a crucial role in determining the magnetic properties of Fe3O4 and Fe3O4@SiO2 microspheres while the diameter of the microsphere does not have significant influence on magnetic properties of such a system. Further, the photoluminescence intensity of Fe3O4 microspheres gets significantly enhanced upon SiO2 coating. A cyclic voltammetric study suggests that S1 can act as a good electrical double layer capacitor (EDLC) above a scan rate of 0.04 V s(-1) while S2 exhibits excellent performance as EDLC in a scan range from 0.01 to 0.06 V s(-1). Thus, S2 is a potential candidate for fabrication of EDLCs.

Solid pseudopapillary tumour of pancreas.

Solid pseudopapillary tumour of pancreas (SPT) is an extremely rare pancreatic tumour, which has a low malignant potential and occurs mainly in young women. Pathologic and imaging findings include a well defined encapsulated pancreatic mass with cystic and solid components with evidence of haemorrhage. This is a case of a 16 years old girl who presented with upper abdominal pain of long duration and epigastric mass on palpation. Computed Tomography (CT) scan demonstrated a large well defined heterogenous attenuation mass of solid enhancing and cystic non enhancing areas, arising from the head of the pancreas. Radiologically it was diagnosed as a case of pancreatic neoplasm. Fine needle aspiration cytology (FNAC) and histopathology of the biopsy material diagnosed as solid pseudopapillary tumour of pancreas.

Neonatal uterine prolapse - a case report.

Uterine prolapse is commonly seen in the geriatric age group. Congenital vaginouterine prolapse is a rare condition occurring in neonates and is usually associated with spinal cord malformations in about 85% of cases. Several modalities of treatment have been described for neonatal uterine prolapse. Conservative treatment in the form of simple digital reposition, use of pessary or other self-retaining device is usually sufficient to treat this condition, which is self-limiting and regressive. Here we report our first case of neonatal uterine prolapse, managed successfully with simple digital reposition.