Gapless points of dimerized quantum spin chains: analytical and numerical studies

We study the locations of the gapless points which occur for quantum spin chains of finite length (with a twisted boundary condition) at particular values of the nearest neighbor dimerization, as a function of the spin S and the number of sites. For strong dimerization and large values of S, a tunneling calculation reproduces the same results as those obtained from more involved field theoretic methods using the non-linear sigma-model approach. A different analytical calculation of the matrix element between the two Neel states gives a set of gapless points; for strong dimerization, these differ significantly from the tunneling values. Finally, the exact diagonalization method for a finite number of sites yields a set of gapless points which are in good agreement with the Neel state calculations for all values of the dimerization, but the agreement with the tunneling values is not very good even for large S. This raises questions about possible corrections to the tunneling results.Comment: Revtex4, 10 pages including 5 figure

The V Advancement Flap Sans Y Closure in Treatment of Volar Foot Ulcers

Background: Management of foot ulcer is challenging for plastic surgeons owing to inherent sturdiness of the volar skin and also the necessity to give a robust cover to ensure functionality including weight bearing. This study was conducted to examine the results of our technique of single or double ‘V’ advancement flap sans the ‘Y’ closure of the classical ‘VY’ flap, which was found to be technically simple for the management of plantar ulcers in our foot ulcer patients. Methods and Material: 37 patients hospitalized for the management of foot plantar ulcer, who underwent repair with our modified ‘V’ flap advancement without ‘Y’ closure technique, at our institution were included in the study. Demographic data, disease-related parameters, technique related complications data were recorded and analysed. Technique complications or sequelae, if any, were accounted. Descriptive statistics was used to summarize the findings. Results: In our study, 23 men and 14 women were there with their ages ranging from 15 to 87 years (mean = 54.1 years). The diameter of the ulcers ranged from 14 to 26 mm with mean of 19.3 mm. Unilateral V (-Y) advancement flap was used in 26 cases and in 11 cases bilateral V (-Y) advancement flap was used. Complications included wound dehiscence (3) and partial flap loss (1) of which 3 required redo surgeries while one healed with secondary intention. Conclusions: Though a relatively small study group our technique well suited the needs for plantar ulcer wound closure with acceptable complication rate. Key Messages: Foot ulcer management is a therapeutic challenge which, if managed efficiently reduces encumbrance. Our technique represents a useful and reliable technique with advantages of excellent colour and texture matching and primary donor site closure. Keywords: VY advancement flap, Plantar foot ulcer, Diabetic ulcer, Malignant foot ulcer, Trophic ulcer, Traumatic ulce

EVALUATION OF GENOTOXICITY PROFILE OF JASADA BHASMA (A ZINC-BASED MINERAL FORMULATION) IN SWISS ALBINO MICE

  Objective: Genotoxicity is regarded as one of the potential risk factors for causing pathological diseases. It was confirmed that many chemicals have the mutagenic activity which leads to cancer. A compound which interacts with genetic material DNA and shows adverse effects by altering its structure or function is referred to as genotoxic.Methods: The present study involved 40 Swiss albino mice weighing between 25 and 30 g body weights categorized into four different groups. Group-I (normal control) received 0.5% carboxymethyl cellulose as vehicle. Group-II (toxicant control) received 40 mg/kg/body weight cyclophosphamide on the 28th day. Group-III and IV received test drug JB 15.6 mg/kg and 78 mg/kg, respectively, for 28 consecutive days. Blood samples were collected and processed for evaluating by comet assay. The animals were sacrificed and collected the bone marrow from both the femur for chromosomal aberration and micronuclei assay.Results: JB administered at two different dose levels did not show any significant changes in the comet assay parameters, no micronucleus was found and did not produce any chromosomal aberrations both numerically and structurally when compared to positive test control group.Conclusion: The genotoxicity evaluation of JB did not show any chromosomal aberrations and presence of micronucleus. Thus, the safety data will refine therapeutic utility of JB encouraging their rationale use and translate into greater and broader utilization of JB

Expression, purification and characterization of a biologically active and thermally stable human lysyl oxidase

Lysyl oxidase (LOX), a promising therapeutic target for the progression of cancer and fibrosis, has not been well characterized yet. A major difficulty faced in LOX characterization is its lack of solubility in common buffers. In this study, mature LOX (mLOX) was cloned, purified and its purity was ascertained by mass spectroscopy. Through screening various buffers, 0.2 M glycine-NaOH buffer with 10% glycerol pH 8.0 was identified to maintain mLOX in its soluble state. About 67% of the refolded mLOX was found to be in copper bound state after His-tag removal. Catalytic properties Km and kcat were found to be 3.72 × 10−4 M and 7.29 ×103s−1. In addition, collagen cross-linking in ARPE-19 cells was augmented on exposure to mLOX, endorsing its biological activity. Circular Dichroism revealed that mLOX comprises 8.43% of α-helix and 22% of β-strand and it was thermally stable up to 90°C. Disulfide linkage imparts the structural stability in LOX which was experimentally ascertained with intrinsic and extrinsic fluorescence studies

Cerebral schistosomiasis

Although schistosomiasis (bilharzia) is one of the most common parasitic infections in humans, schistosomal infection of the nervous system is rare. This report is of an unusual case of primary cerebral schistosomiasis and describes its magnetic resonance imaging appearance

Clinical application of acellular matrix derived from the bubaline diaphragm and caprine rumen for the repair of abdominal wall defects in animals

The abdominal wall hernias resulting due to trauma or other clinical conditions are common in animals. Large hernias required the use of synthetic mesh, which is costly and may result in infection, fistula formation, and pain. Application of biomaterials in hernia repair causes a reduction in pain, reduced recovery time, and rate of recurrence. The study was undertaken to test the acellular bubaline diaphragm matrix (BDiaM) and acellular caprine rumen matrix (CRuM) for the repaired hernia in clinical cases. Fresh bubaline diaphragm and caprine rumen were decellularized using sodium deoxycholate (1% for CRuM and 2% for BDiaM) for 48h. Acellularity was ascertained histologically and by DNA quantification. Histologically, both the matrices showed complete acellularity and orderly arranged collagen fibers after 48 h. The DNA contents were significantly (P0.05) reduced in both the matrices in comparison to the native matrices. The BDiaM and CRuM matrices were applied in eight and nine clinical cases of abdominal wall defects, respectively. Animals with BDiaM and CRuM matrices recovered uneventfully and remained sound at least up to 3 months. Hematological and immunological findings were unremarkable. BDiaM and CRuM matrices showed good results without complications. Keywords:Biocompatibility, Bubaline diaphragm matrix, Caprine rumen matrix, DNA quantification, ELISA, SDS-PAG

Conceptual Design of Fuel Dumping System in Aircraft

Airlines release the unburned jet fuel into the atmosphere to reduce the weight of aircraft before landing. Sometimes, aircraft reach a weight more than takeoff weight while departing from the airport. Therefore, the pilot follows the ATC comment to dump fuel into the atmosphere to reduce the aircraft\u27s weight to avoid accidents. Due to fuel dumping, an airline faces fuel consumption, loss, and several diseases affect environmental pollutants, and living things. The total fuel consumption of commercial airlines worldwide in 2021 is 57 billion gallons. If jet fuel routinely hit the ground, it would pollute water and land and damage crops and biodiversity. With this, we have worked on the project to rescue fuel dumping into the atmosphere and save living things from various diseases

Implementation of gate-all-around gate-engineered charge plasma nanowire FET-based common source amplifier

This paper examines the performance of a Gate-Engineered Gate-All-Around Charge Plasma Nanowire Field Effect Transistor (GAA-DMG-GS-CP NW-FET) and the implementation of a common source (CS) amplifier circuit. The proposed GAA-DMG-GS-CP NW-FET incorporates dual-material gate (DMG) and gate stack (GS) as gate engineering techniques and its analog/RF performance parameters are compared to those of the Gate-All-Around Single-Material Gate Charge Plasma Nanowire Field Effect Transistor (GAA-SMG-CP NW-FET) device. Both Gate-All-Around (GAA) devices are designed using the Silvaco TCAD tool. GAA structures have demonstrated good gate control because the gate holds the channel, which is an inherent advantage for both devices discussed herein. The charge plasma dopingless technique is used, in which the source and drain regions are formed using metal contacts and necessary work functions rather than doping. This dopingless technique eliminates the need for doping, reducing fluctuations caused by random dopants and lowering the device’s thermal budget. Gate engineering techniques such as DMG and GS significantly improved the current characteristics which played a crucial role in obtaining maximum gain for circuit designs. The lookup table (LUT) approach is used in the implementation of the CS amplifier circuit with the proposed device. The transient response of the circuit is analyzed with both the device structures where the gain achieved for the CS amplifier circuit using the proposed GAA-DMG-GS-CP NW-FET is 15.06 dB. The superior performance showcased by the proposed GAA-DMG-GS-CP NW-FET device with analog, RF and circuit analysis proves its strong candidature for future nanoscale and low-power applications

Human Papillomavirus Associated Oropharyngeal Carcinoma-Diagnosis and Management

Head and neck squamous cell carcinomas arise from the mucosa of the upper aerodigestive tract and is often driven by risk factors like tobacco and alcohol consumption. Most of the time patients present with locally advanced stages and the outcome is poor, despite recent advances in multi-modality treatment. The epidemiology of the disease has changed over the last decade with the introduction of a separate clinical entity; Human Papillomavirus (HPV) associated head and neck cancer. The tumorigenesis is different from that of tobacco and alcohol-driven malignancies. These tumors have a better response to treatment owing to their inherent genetic makeup and carry an excellent prognosis. The current school of thought is to reduce the long-term morbidities associated with various treatment modalities, as these patients tend to survive longer. The best management of HPV-associated oropharyngeal cancer is under active investigation