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The magnetic field distribution in the rails is a crucial factor in comprehending railgun behaviour. The projectile's rapid movement has a significant impact on the magnetic field. If the dispersion of the magnetic field conclusions regarding the conductors are known suitable methods can be used to sketch the magnetic field distribution. The railgun operates on the premise that a high current flow through the rails and armature will create a strong magnetic field. As a result, before designing magnetic shielding, it is necessary to study the features of the magnetic field distribution. The shape of rail and armature cross section is very essential in rail gun design as it determines the magnetic field distribution over rail and armature. The rail gun geometries with rectangular, convex and concave rail cross-sections are compared and simulated using finite element method (FEM). This method is used to determine the magnetic field distribution over rail and armature by sweeping armature position for different rail cross sections. It is observed that for the different rail/armature shapes like rectangular, convex and concave shapes, the C shaped convex armature possesses strong magnetic fields with minimum current density concentration at the throat and trailing end of the armature. From simulation, it can be shown that the magnetic flux density is a descending function of the central angle. The electromagnetic (EM) rail gun launching mechanism was therefore proven to be compatible with the circular concave armature.

Soil organic carbon (SOC) plays a vital role in the global carbon cycle and is a potential sink for carbon dioxide. Agricultural management practices can support carbon sequestration and, therefore, offer potential removal strategies whilst also improving overall soil quality. Meta-analysis allows one to summarize results from primary articles by calculating an overall effect size and to reveal the source of variation across studies. The number of meta-analyses published in the field of agriculture is continuously rising. At the same time, more and more articles refer to their synthesis work as a meta-analysis, despite applying less than rigorous methodologies. As a result, poor-quality meta-analyses are published and may lead to questionable conclusions and recommendations to scientists, policymakers, and farmers. This study aims at quantitatively analyzing 31 meta-analyses, published between the years of 2005 and 2020, studying the effects of different management practices on SOC. We compiled a set of quality criteria suitable for soil and agricultural sciences by adapting existing meta-analytical guidelines from other disciplines. The set is supported by a scoring scheme that allows for a quantitative analysis. The retrieved meta-analyses were structured according to 11 management categories, such as tillage, cover crops, crop residue management, and biochar application, which allowed us to assess the state of knowledge on these categories. Major deficiencies were found in the use of standard metrics for effect size calculation, independence of effect sizes, standard deviation extraction for each study, and study weighting by the inverse of variance. Only 1 out of 31 SOC meta-analyses, which studied the effects of no tillage/reduced tillage compared with conventional tillage, was found to be of high quality. Therefore, improved meta-analyses on the effects of organic agriculture, biochar, fertilization, or crop diversification on SOC are urgently needed. We conclude that, despite efforts over the last 15 years, the quality of meta-analyses on SOC research is still low. Thus, in order for the scientific community to provide high-quality synthesis work and to make advancements in the sustainable management of agricultural soils, we need to adapt rigorous methodologies of meta-analysis as quickly as possible.

Due to their high strength-to-weight ratio, fibre reinforced polymer (FRP) composite laminates are extensively employed in vehicle, aeroplane, marine, and machine tool structures. These FRP structures are subjected to vibration and fatigue under dynamic service conditions. The purpose of this study is to see how cyclic loading affects the free vibration characteristics of FRP composite laminates. Hybrid composite laminates comprised of natural jute fibre and synthetic glass fibre are being examined as a way to promote the concept of environmentally friendly materials in structural applications. For both natural and synthetic fibres, woven fabric forms are chosen because they produce balanced characteristics in both the fibre plane and thickness direction. Epoxy resin is employed as a matrix. Hand layup method is used to fabricate four layered glass/jute hybrid composite laminates with two different stacking sequences. Mechanical parameters such as tensile strength and flexural strength are evaluated according to ASTM standards for the prepared laminates. A completely reversed bending fatigue test apparatus is built in-house to apply cyclic load to the glass/jute hybrid composite specimen with the specified amplitude and frequency. At various levels of cyclic loading, the free vibration properties of a glass/jute hybrid composite specimen are measured using the impulse excitation technique. The optimal stacking sequence of glass/jute hybrid composite laminates for dynamic service conditions is established based on experimental data of mechanical properties and vibration characteristics of glass/jute hybrid composite laminates.

Lung cancer is a fatal disease caused by an abnormal proliferation of cells in the lungs. Similarly, chronic kidney disorders affect people worldwide and can lead to renal failure and impaired kidney function. Cyst development, kidney stones, and tumors are frequent diseases impairing kidney function. Since these conditions are generally asymptomatic, early, and accurate identification of lung cancer and renal conditions is necessary to prevent serious complications. Artificial Intelligence plays a vital role in the early detection of lethal diseases. In this paper, we proposed a modified Xception deep neural network-based computer-aided diagnosis model, consisting of transfer learning based image net weights of Xception model and a fine-tuned network for automatic lung and kidney computed tomography multi-class image classification. The proposed model obtained 99.39% accuracy, 99.33% precision, 98% recall, and 98.67% F1-score for lung cancer multi-class classification. Whereas, it attained 100% accuracy, F1 score, recall and precision for kidney disease multi-class classification. Also, the proposed modified Xception model outperformed the original Xception model and the existing methods. Hence, it can serve as a support tool to the radiologists and nephrologists for early detection of lung cancer and chronic kidney disease, respectively.

Induction motors based electric drives are dominated in many applications due to their superior characteristics over other drives including cost. An effect control method is required to reduce ripples in the torque. A direct torque control (DTC) is implemented by various scholars recently, however for further reduction of ripples in torque a modified DTC is implemented in this paper. The proposed method considerably alleviates the computational burden of control technique on chip. The selection of inverter switching vectors is identified for restricting the torque and flux errors within their respective hysteresis bands. Fastest responses of torque, speed and flux are achieved. This paper also includes the incorporation of modeling and designing of DTC with induction motor to enhance comprehension. Extensive results under various operating conditions are presented in this paper to enhance the importance of the improved DTC.

The complex anatomy of the mandibular condyle makes its fracture management challenging and debatable. Apart from this, the approaches to condyle are also challenging as most of them depend on the surgical expertise. The retromandibular approach which was initially proposed for the vertical sub condylar osteotomies was later popularized for condyle fracture management. It is considered to be a gold standard approach in the management of low condylar fractures. Although it has its own demerits in managing high condylar fracture due to its poor access and visibility, the major complications of temporary facial nerve paresis and sialocele are very less compared to other approaches. However, modified extracorporeal plating combined with retromandibular approach proves to be effective in managing high condylar fracture. In this article, we discuss about a case of bilateral neck of condyle fracture that has been managed with the combined modified extracorporeal plating with retromandibular approach and has been followed with no complications for about 1 year.

The problem considered: This multi-centric study analyzed data of COVID-19 patients and compared differences in symptomatology, management, and outcomes between vaccinated and vaccine-naive patients. Methods: All COVID-19 positive individuals treated as an in-or out-patient from the 1stMarch to 15th May 2021 in four selected study sites were considered for the study. Treatment details, symptoms, and clinical course were obtained from hospital records. Chi-square was used to test the association of socio-demographic and treatment variables with the vaccination status and binary logistic regression were used to obtain the odds ratio with a 95% confidence interval. Results: The analysis was of 1446 patients after exclusion of 156 with missing data of which males were 57.3% and females 42.7%. 346 were vaccinated; 189 received one dose and 157 both doses. Hospitalization was more in vaccinated (38.2% vs 27.4%); ICU admissions were less in vaccinated (3.5% vs 7.1%). More vaccinated were symptomatic (OR = 1.5); half less likely to be on non-invasive ventilation (OR = 0.5) while vaccine naive patients had 4.21 times the risk of death. Conclusion: Severe infection, duration of hospital stays, need for ventilation and death were significantly less among vaccinated when compared with vaccine naive patients.

Background: The diabetic subjects would have impaired oral stereognostic ability (OSA) compared with normal subjects due to diabetic neuropathy and microcirculatory disturbances. This study was conducted to compare the OSA between diabetic and nondiabetic complete denture wearers with and without denture. Materials and Methods: In this in vivo study the present comparative study comprised of seventy edentulous subjects (36 males and 34 females), aged from 35 to 84 rehabilitated with complete dentures (among them 35 were diabetic and 35 subjects were nondiabetic complete denture wearer). The OSA tests were conducted using acrylic test samples of 12 shaped forms, which were placed in patient's mouth for a given period of time for identification and scored according to three-point scale as OSA score and the identification time was also recorded. The data obtained were analyzed using Chi-square test, t-test, and Pearson's correlation coefficient (P < 0.05). Results: In this study, diabetic complete denture wearers got the mean OSA score of 12.43 ± 3.93 without dentures, which was lower than nondiabetic complete denture wearer group (14.82 ± 4.44). There was a significant difference (P = 0.020*) in the identification of test pieces. Conclusion: Within limitations of this study, diabetic complete denture wearers showed decreased OSA than nondiabetic subjects, particularly it was significant while not wearing dentures. Oral stereognosis may be used as one of the clinical aids in predicting patient's performance to a prosthesis. Based on their response, we can educate the patient about the prognosis.

This work analyses the effect of Laccase and Xylanase enzyme treatment on chemical and mechanical properties of banana fiber. Properties such as chemical composition, density, tensile strength, and color were analyzed. The removal of lignin increased with increase in enzymes concentration. Lignin removal was observed to be higher for Laccase treatment. The hemicellulose removal was higher for Xylanase treatment and the results were confirmed by FTIR spectrum. It is evident that cellulose%, density and tensile strength increased up to 15% enzyme treatment concentration and then started declining at 20% enzyme concentration in the case of both enzymes, whereas the moisture regain percentage of the fiber decreased with increase in enzyme concentration. The effects of enzymatic treatments are clearly visible in the SEM images.

Early detection of cancer greatly decreases the morbidity and mortality rates and thereby increases the 5-year survival rates. In developing countries like India where the disease is highly prevalent focus is mainly on decreasing the mortality rates which can be easily achieved by detection at an asymptomatic stage. Visual examination has been the standard screening method for screening oral cancer through several decades, and it is well known that conventional visual examination is limited to subjective interpretation and cannot be easily achieved in certain anatomical sites. As a solution to all these adjunctive techniques have emerged, and it has been widely used. An effort is made through this paper to review the most commonly used adjunctive aids for the detection of premalignancy and cancer.