310 research outputs found

    DESIGN AND OPTIMIZATION OF AN ELECTROMAGNETIC RAILGUN

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    Railgun is a future weapon for shooting long-range targets with high accuracy. Railgun is an economical weapon as it does not use any kind of propellant for shooting a projectile. It uses high impulsive current to generate the necessary force required to hit the target. The US Navy has been planning to implement railgun system on ships as their long-range shooting weapon. Railgun needs to be charged up to a certain voltage level to generate the necessary force to shoot the projectile to achieve the specified target location. It is very important that minimal voltage is required for shooting the projectile to hit the target accurately as it minimizes the losses occurring in the railgun system. This project focuses on solving this challenge by minimizing the railgun’s initial voltage required to shoot a projectile for hitting the target with high accuracy. It also focuses on minimizing the copper losses occurring in the system. In this project, a novel method has been generated which solves both challenges. In this project, a model of the discharging circuit of the railgun and a model of the projectile’s trajectory with and without air drag have been generated using Simulink. Then both of these models are merged using MATLAB. Once this model was complete, it simulates the discharge of the capacitor voltage into the railgun system to achieve the necessary acceleration required to launch a projectile with a certain velocity. It also simulates the trajectory of a projectile. In this project, an optimization technique has been implemented using Fmincon to optimize the shooting accuracy to hit the target with minimum copper losses. This has been achieved by generating a code which optimally chooses the initial input voltage required for discharging and the launch angle at which the railgun is kept. At the end, higher than 97.5 % accuracy has been achieved in hitting the target while reducing the copper loss by more than 6 % for both the cases that were modeled

    Giant organ confined prostatic adenocarcinoma: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>Giant prostatic adenocarcinoma represents a rare and challenging treatment dilemma.</p> <p>Case presentation</p> <p>We describe a case of an otherwise healthy 71-year-old African male who presented with a PSA of 5800 ng/ml and a prostate volume of over 1000cc. Unique aspects of this case include the size of the prostate, the apparent absence of distant metastases, and the safe usage of transabdominal biopsy of this mass.</p> <p>Conclusion</p> <p>We present this case report and review of literature to generate further discussion amongst readers as to management options for this difficult case.</p

    Duration of streptozotocin-induced diabetes differentially affects p38-mitogen-activated protein kinase (MAPK) phosphorylation in renal and vascular dysfunction

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    Background: In the present study we tested the hypothesis that progression of streptozotocin (STZ)-induced diabetes (14-days to 28-days) would produce renal and vascular dysfunction that correlate with altered p38- mitogen-activated protein kinase (p38-MAPK) phosphorylation in kidneys and thoracic aorta. Methods: Male Sprague Dawley rats (350-400 g) were randomized into three groups: sham (N = 6), 14-days diabetic (N = 6) and 28-days diabetic rats (N = 6). Diabetes was induced using a single tail vein injection of STZ (60 mg/kg, I.V.) on the first day. Rats were monitored for 28 days and food, water intake and plasma glucose levels were noted. At both 14-days and 28-days post diabetes blood samples were collected and kidney cortex, medulla and aorta were harvested from each rat. Results: The diabetic rats lost body weight at both 14-days (-10%) and 28-days (-13%) more significantly as compared to sham (+10%) group. Glucose levels were significantly elevated in the diabetic rats at both 14-days and 28-days post-STZ administration. Renal dysfunction as evidenced by renal hypertrophy, increased plasma creatinine concentration and reduced renal blood flow was observed in 14-days and 28-days diabetes. Vascular dysfunction as evidenced by decreased carotid blood flow was observed in 14-days and 28-days diabetes. We observed an up-regulation of inducible nitric oxide synthase (iNOS), prepro endothelin-1 (preproET-1) and phosphorylated p38-MAPK in thoracic aorta and kidney cortex but not in kidney medulla in 28-days diabetes group. Conclusion: The study provides evidence that diabetes produces vascular and renal dysfunction with a profound effect on signaling mechanisms at later stage of diabetes. © 2005 Chen et al; licensee BioMed Central Ltd

    Comparative study to evaluate the awareness about anemia and its complications, among undergraduate and postgraduate medical students- a cross sectional survey study

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    Background: Anemia is a condition in which numbers of red blood cells or their oxygen carrying capacity is insufficient to meet the physiologic needs which vary by age, sex, altitude, smoking and pregnancy status. Iron deficiency anemia is the most common type of anemia in the world. Aim of the study was to compare and evaluate awareness about anemia and its complications among the undergraduate and postgraduate medical students.Methods: A prospective, cross sectional, questionnaire based, survey study was carried out at S.B.K.S. Medical institute and RC, Vadodara. The well-defined, structured questionnaire was prepared, distributed and collected when it was duly filled by undergraduate and postgraduate students. The questionnaire was mainly based upon basic knowledge of anemia, its investigations, treatment, and complications. The answers were evaluated in a structured format and further depending on the scores the participants were grouped as poor (70%). Later, it was subjected to Chi-square test and p value <0.05 were considered to be significant.Results: This study shows that the basic knowledge of anaemia and knowledge pertaining to treatment of anaemia is lacking in undergraduate students as compared to postgraduate students. However it was observed in both the study groups that knowledge about various aspects of anaemia is not optimal.Conclusions: It is a need of hour to impart knowledge of common disorders including anemia to both undergraduate and postgraduate students for the larger benefit of society

    Comparison of the safety and efficacy of intracervical Foleys catheter versus PGE2 gel for induction of labour at term

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    Background: Before the induction of labour cervical ripening is needed for the success of induction to reduce the complication and diminish the rate of cesarean section and duration of labour. Various mechanical methods like Foleys catheter are effective but not much popular because of infection and pharmacological preparations which have more side effects, are used for cervical ripening. Therefore study has been conducted to compare the efficacy and safety of intra cervical Foleys catheter versus PGE2 gel for induction of labour at term. The aims and objectives of this study was to success of induction of labour depends on the cervical status at the time of induction.Methods: A prospective comparative study was conducted in the department of obstetrics and gynecology, L.G. hospital (AMCMET Medical college), Ahmedabad, during period of July 2019 to December 2019. 100 patients at term with a Bishop’s score with various indications for induction were randomly allocated to receive (50 patients) intra cervical Foleys catheter or PGE2 gel (50 patients). Post induction Bishop’s score was noted after 6 hours, 12 hours, 24 hours. Statistical methods used were Student t test and Chi square test to statistically compare the two groups. Differences with a p value of <0.005 was considered statistically significant with confidence limit of 95%.Results: The groups were comparable with respect to maternal age, gestational age, parity, indication of induction and initial bishops score. Both groups showed significant change in the Bishops score, 5.10±1.55 and 5.14±1.60 for Foleys catheter and PGE2 gel, respectively, p<0.001. Fetal outcome was noted in NICU admission and fetal death. No significant difference between two groups.Conclusions: This study shows that both Foleys catheter and PGE2 gel were equally effective in pre induction cervical ripening

    Targeted Doxorubicin Delivery to Brain Tumors via Minicells: Proof of Principle Using Dogs with Spontaneously Occurring Tumors as a Model

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    BACKGROUND: Cytotoxic chemotherapy can be very effective for the treatment of cancer but toxicity on normal tissues often limits patient tolerance and often causes long-term adverse effects. The objective of this study was to assist in the preclinical development of using modified, non-living bacterially-derived minicells to deliver the potent chemotherapeutic doxorubicin via epidermal growth factor receptor (EGFR) targeting. Specifically, this study sought to evaluate the safety and efficacy of EGFR targeted, doxorubicin loaded minicells (designated EGFRminicellsDox) to deliver doxorubicin to spontaneous brain tumors in 17 companion dogs; a comparative oncology model of human brain cancers. METHODOLOGY/PRINCIPLE FINDINGS: EGFRminicellsDox were administered weekly via intravenous injection to 17 dogs with late-stage brain cancers. Biodistribution was assessed using single-photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI). Anti-tumor response was determined using MRI, and blood samples were subject to toxicology (hematology, biochemistry) and inflammatory marker analysis. Targeted, doxorubicin-loaded minicells rapidly localized to the core of brain tumors. Complete resolution or marked tumor regression (>90% reduction in tumor volume) were observed in 23.53% of the cohort, with lasting anti-tumor responses characterized by remission in three dogs for more than two years. The median overall survival was 264 days (range 49 to 973). No adverse clinical, hematological or biochemical effects were observed with repeated administration of EGFRminicellsDox (30 to 98 doses administered in 10 of the 17 dogs). CONCLUSIONS/SIGNIFICANCE: Targeted minicells loaded with doxorubicin were safely administered to dogs with late stage brain cancer and clinical activity was observed. These findings demonstrate the strong potential for clinical applications of targeted, doxorubicin-loaded minicells for the effective treatment of patients with brain cancer. On this basis, we have designed a Phase 1 clinical study of EGFR-targeted, doxorubicin-loaded minicells for effective treatment of human patients with recurrent glioblastoma

    Initial psychological responses to influenza A, H1N1 ("Swine flu")

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    Background The outbreak of the pandemic flu, Influenza A H1N1 (Swine Flu) in early 2009, provided a major challenge to health services around the world. Previous pandemics have led to stockpiling of goods, the victimisation of particular population groups, and the cancellation of travel and the boycotting of particular foods (e.g. pork). We examined initial behavioural and attitudinal responses towards Influenza A, H1N1 ("Swine flu") in the six days following the WHO pandemic alert level 5, and regional differences in these responses. Methods 328 respondents completed a cross-sectional Internet or paper-based questionnaire study in Malaysia (N = 180) or Europe (N = 148). Measures assessed changes in transport usage, purchase of preparatory goods for a pandemic, perceived risk groups, indicators of anxiety, assessed estimated mortality rates for seasonal flu, effectiveness of seasonal flu vaccination, and changes in pork consumption Results 26% of the respondents were 'very concerned' about being a flu victim (42% Malaysians, 5% Europeans, p < .001). 36% reported reduced public transport use (48% Malaysia, 22% Europe, p < .001), 39% flight cancellations (56% Malaysia, 17% Europe, p < .001). 8% had purchased preparatory materials (e.g. face masks: 8% Malaysia, 7% Europe), 41% Malaysia (15% Europe) intended to do so (p < .001). 63% of Europeans, 19% of Malaysians had discussed the pandemic with friends (p < .001). Groups seen as at 'high risk' of infection included the immune compromised (mentioned by 87% respondents), pig farmers (70%), elderly (57%), prostitutes/highly sexually active (53%), and the homeless (53%). In data collected only in Europe, 64% greatly underestimated the mortality rates of seasonal flu, 26% believed seasonal flu vaccination gave protection against swine flu. 7% had reduced/stopped eating pork. 3% had purchased anti-viral drugs for use at home, while 32% intended to do so if the pandemic worsened. Conclusion Initial responses to Influenza A show large regional differences in anxiety, with Malaysians more anxious and more likely to reduce travel and to buy masks and food. Discussions with family and friends may reinforce existing anxiety levels. Particular groups (homosexuals, prostitutes, the homeless) are perceived as at greater risk, potentially leading to increased prejudice during a pandemic. Europeans underestimated mortality of seasonal flu, and require more information about the protection given by seasonal flu inoculation

    Diagnostic assays for leprosy based on T-cell epitopes.

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    To date, only a limited number of antigens have been described as specific for Mycobacterium leprae, and in many cases, homologues have subsequently been shown to exist in mycobacteria such as M. avium and M. intracellulare. A Leprosy Synthetic Peptide Skin Test Initiative was established by the Steering Committee on the Immunology of Mycobacteria of the UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases, to investigate the potential of synthetic peptides that encode T-cell epitopes as diagnostic tools, which could be used to develop a skin-test reagent specific for leprosy. Such M. leprae-specific peptides should have unique amino acid sequences, or significant sequence-dissimilarity from those in other mycobacteria. Synthetic peptides, 15 amino acids long, were synthesised from 33 genes or open reading frames within the M. leprae genome. Tuberculoid leprosy patients from four leprosy-endemic countries, Brazil, Ethiopia, Nepal and Pakistan, were tested as subjects known to have been infected with M. leprae, and to make good T-cell responses to antigens of M. leprae; UK blood donors were used as non-exposed or non-infected subjects. Peptides inducing potentially specific responses in leprosy patients and not in UK controls, and those inducing cross-reaction responses, present in both leprosy patients and non-exposed, non-infected controls, were identified. A difference from the equivalent M. tuberculosis sequence of five or more amino acid residues did not, by itself, identify peptides that were M. leprae-specific, suggesting that many of these peptides may have homologues in environmental mycobacteria. To date, this approach has identified a number of peptides with greater than 90% specificity and 19-47% sensitivity, which are undergoing further specificity-testing. Such peptides would have great potential as T-cell reagents with which to monitor exposure to M. leprae within communities, formulated either as skin-test reagents, or as antigens for tests in vitro
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