59 research outputs found

    Aging behavior of intercritically quenched ductile iron

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    Although extensive aging and strain aging (bake hardening, BH) studies have been carried out on dual-phase steels, the aging behavior of the dual matrix structure (DMS) ductile iron (DI), as a potential way to improve its mechanical properties, has not been addressed until now. This research was designed to study the aging behavior of DI with a ferrite-martensite matrix structure. DMS-DI with a martensite volume fraction of 30% was produced by intercritical austenitizing at 785 ◦C followed by quenching in water to room temperature. Aging treatments were carried out without prestraining at aging temperatures of 140, 170, and 220 ◦C for 2–10,000 min. DMS-DI was investigated by light optical microscopy (LOM) for unaged samples and scanning electron microscopy (SEM) for selected samples after aging treatments. The effect of aging conditions on the mechanical properties were investigated. Microhardness measurements for ferrite and martensite were also examined as a function of aging conditions. The increase in yield strength due to aging was determined. The results indicate that the aging conditions have a small effect on the ultimate tensile strength UTS. It is shown that the yield strength increased to a maximum value of 45 MPa (~11% increase) after aging for particular time, which is found to be dependent on the aging temperature. The peak aging response is followed by a decrease in yield strength, which is observed to be attributed to martensite tempering as confirmed by microhardness measurements

    Study of serum levels of visfatin amongst pre-diabetic obese patients

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    Background: Insulin resistance, pre-diabetes, and obesity have all been linked to excess adiposity. Proinflammatory adipokine visfatin is thought to play a key role in type 2 diabetes inflammation. Objective: This study aimed to estimate visfatin level among prediabetic obese patients and to observe and detect the interplay between visfatin, insulin resistance and obesity.Patients and methods: 96 adult subjects were studied in case-control research at Internal Medicine Department and Clinical Pathology Department, Zagazig University Hospital. The study was carried out from January 2021 to November 2021. Subjects were divided into 3 groups: Group (1) included 24 healthy individuals as a control group, group (2) included 48 prediabetic individuals and group (3) that included 24 patients type 2 diabetes who never been treated in any of these. Serum visfatin was assessed in all participants.Results: Diabetes mellitus (DM) patients had higher visfatin levels than those with impaired glucose tolerance (IGT) or impaired fasting glucose (IFG). Visfatin had a significant positive correlation with BMI, WC, FBS, PPS, HA1c, LDL, fasting insulin, and HOMA IR, while HDL had a significant negative correlation.Conclusion: Visfatin levels were significantly linked to type 2 diabetes. HOMA-IR, fasting insulin, and BMI all showed a strong positive correlation with visfatin levels, suggesting that it may be a useful biomarker for detecting type 2 diabetes

    To which extent a convalescent plasma therapy could be a benefit for COVID-19 patients?

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    The emergence of an unprecedented pandemic SARS-COV-2 caused perplexed in the medical community because of a high infection rate and rising mortality among COVID-19 patients. Till now, there is no particular treatment for the disease; nevertheless, there is an extensive effort from scientists to find out an immediate therapeutic plan to show how to deal with the current situation. One of the solutions currently presented is Convalescence plasma (CP). Through this narrative review, we will shed light on CP's efficiency as a therapeutic agent for COVID-19, especially there is no proven vaccine or antiviral available up to date. CP could be considered one of the therapeutic approaches, but some limitations are still considered before it is established as a therapeutic agent. Along with evaluating CP from blood donors, the plasma companies could take future steps by manufacturing a target dose of globulins that contain standardized antibody, to reach the terms of health setting administering therapy

    Small iron pieces effect on the output of single slope solar still

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    Solar distillation is an environmental technique that uses solar energy to treat polluted water. In this context, two solar stills of the same size (0.5 x 0.5 m) were exposed to the sun i.e., under the same weather conditions to see the effect of small iron parts on the production of pure water. The results showed that the modified solar still SSM which contained iron pieces had an improvement rate of 23.46% compared to the reference solar still SSR

    The Investigation of Lead Borate Glass Composites for Boron Neutron Capture Therapy Shielding

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    In this work, we studied the lead borate glass composites to optimize its shielding properties of thermal neutrons and gamma-rays for Boron Neutron Capture Therapy (BNCT) applications. Attenuation coefficients, half-value layer (HVL), and tenth-value layer (TVL) were measured for a broad range of gamma-ray energies, i.e., 356, 511, 662, 1173, 1274, and 1332 keV experimentally. Theoretical results using XCOM software show an agreement with the NaI(Tl) detector-based experimental measurements. The attenuation of collimated thermal neutrons, from Cf-252 source, was simulated using Monte Carlo-based code and compared experimentally with measurements by BF3 detector. A reasonable agreement between simulations and experiments was observed, suggesting that the shielding properties of lead borate glass (LBG) composites are monotonically increasing with the increasing of the lead and boron additives

    Evaluation of Fine-needle Aspiration Cytology (FNAC) Sensitivity Compared to PCR for Diagnosing Tuberculosis Lymphadenitis

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    Background: Tuberculosis (TB) is a major healthcare burden in Sudan and other developing countries, it is considered the second most common cause of death from infectious diseases after those due to AIDS. In Sudan, TB lymphadenitis (TBLA) remains one of the major health problems. This descriptive cross-sectional study was conducted at the University of Medical Sciences and Technology (UMST) and Total Labcare Diagnostic Center (TDC). The study aims to compare the sensitivity of Fine Needle Aspiration Cytology (FNAC) smears with that of the Polymerase Chain Reaction (PCR) for the diagnosis of TBLA. Materials and Methods: Fifty-five dry smears were obtained using fine-needle aspiration (FNA) from an enlarged lymph node. PCR was applied to detect the target gene (IS6110). May-Grunwald-Giemsa (MGG) or Diff quick stains were used. Results: Two (4%) patients with TBLA were non-necrotic, while fifty-three of them (96%) were necrotic. Moreover, 17 (30%) fine-needle lymph node aspiration specimens were confirmed by PCR to be positive for Mycobacterium tuberculosis complex (MTB complex) while 38 (70%) of them were negative. Conclusion: There was no significant difference between the sensitivity of PCR and that of FNAC (P-value = 0.33)

    Higher nitric oxide levels are associated with disease activity in Egyptian rheumatoid arthritis patients

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    AbstractBackgroundOxidative stress generated within inflammatory joints can produce autoimmune phenomena and joint destruction. Radical species with oxidative activity, including reactive nitrogen species, represent mediators of inflammation and cartilage damage.ObjectivesTo assess serum nitric oxide as a marker of oxidative stress in Egyptian patients with rheumatoid arthritis and its relation to disease activity.MethodsEighty patients with rheumatoid arthritis were divided into 2 groups, according to the DAS-28 score: Group I: 42 patients with disease activity, and Group II: 38 patients with no disease activity. Forty age- and sex-matched individuals were included as control group (Group III). Routine laboratory investigations were done, and nitric oxide was measured using Elisa. Hand plain radiographies were done for radiological status scoring using the Sharp method.ResultsA comparison between nitric oxide in all three groups showed a highly significant difference (p < 0.001), significantly higher levels were obtained among rheumatoid arthritis patients in comparison to controls, and higher levels were obtained in patients with active disease (mean±SD 82.38±20.46) in comparison to patients without active disease (35.53±7.15). Nitric oxide in Group I showed a significant positive correlation with morning stiffness (r=0.45), arthritis (r=0.43), platelet count (r=0.46), erythrocyte sedimentation rate (r=0.83), C-reactive protein (r=0.76) and Disease Activity Score (r=0.85). Nitric oxide showed a significant positive correlation (r=0.43) with hand radiographies (Sharp score) in Group I.ConclusionThere are increased levels of nitric oxide in the serum of patients with rheumatoid arthritis. Nitric oxide correlates significantly with disease activity, inflammatory markers and radiological joint status

    Is Prolonged Sitting a Risk Factor in Developing Hemorrhoids and Anal Fissures?

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    Background: Anal fissures and hemorrhoids are common anal conditions. They cause significant morbidity, social embarrassment, and work absenteeism. In addition, they form a significant workload on the healthcare system. Nevertheless, the etiology of these conditions is still contentious. It has been observed that hemorrhoids and anal fissures are associated with prolonged sitting. This study aims to investigate this observation.Methods: This is a case–control study. We compared 81 patients with symptomatic and endoscopically proven hemorrhoids and/or anal fissures with 162 controls with no symptoms or endoscopic evidence of perianal disease. The study was conducted at Khartoum North Teaching Hospital (KNTH) endoscopy unit between January and December 2019. Demographic data, sitting hours per day, and endoscopic findings of patients and controls were recorded in a proforma. The cases and controls were matched for age, sex, and bowel habits. Data were analyzed and compared using the SPSS version 23.Results: The mean sitting hours for cases was 5.99 (SD 3.4) whereas that for controls was 4.0 (SD 3.0) with a highly significant difference (P &lt; 0.001). Sitting for 5 hr or more per day (exposure) was associated with an increased risk of developing hemorrhoids and/or anal fissures [odds ratio 3.68, 95% CI: 2.1–6.47].Conclusion: The study showed that sitting down for 5 hr or more per day might increase the risk of developing hemorrhoids and/or anal fissures. This finding could help in the prevention and treatment of these diseases and the reduction of recurrences

    Snakebite-Associated Infections: A Systematic Review and Meta-Analysis

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    Snakebites still constitute a significant public health problem in developing countries and are considered a neglected tropical condition by the WHO. Snake accidents are associated with substantial morbidity and mortality and may produce secondary complications, such as severe infections. The objective of this systematic review was to determine the prevalence of snakebite infections and characterize the bacteria isolated from these infections. A systematic literature review in five databases was carried out to assess the prevalence of snakebite infection. A meta-analysis was performed using a random-effects model to calculate the pooled prevalence and 95% CIs. Cochran’s Q test and the I2 statistic were used to assess between-study heterogeneity. The pooled prevalence of infection due to snakebite was 27.0% (95% CI: 22.0–32.0%), with high heterogeneity among studies (I2 5 99.7%). The prevalence was higher in Asia (32%) than in the Americas (21%). Snakebite infections required surgical interventions in 68% (95% CI: 37.0–98.0%). The leading group of pathogens identified corresponded to Gram-negative bacteria (63%), particularly Morganella morganii (32%), but also, Gram-positive cocci (40%), especially Enterococcus spp. (23%) and Staphylococcus aureus (15%). However, multiple other pathogens, including anaerobes, were found. A high prevalence of snakebite-associated infection has been described, primarily due to M. morganii, with the corresponding implications for empirical therapy. Rational use of antimicrobials is recommended, and this should guide initial empirical treatment. Moreover, isolation and identification of the possible bacteria present in snakebite wounds is recommended in all cases to confirm or rule out associated infection.Universidad Científica del SurRevisión por pare

    Safety and efficacy of percutaneous nephrolithotripsy in comorbid patients: A 3 years prospective observational study

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    Purpose: To report the result of percutaneous nephrolithotripsy (PCNL) via standard nephrostomy tract in a single training institution. The perioperative complications in relation to the comorbid state are particularly assessed. Patients and methods: A prospective interventional study between January 2019 to November 2022, included 210 patients scheduled for PCNL. The average age was 40.3 ± 11.8 years (range 18- 67 years). Patients were categorized into two groups. The first group comprised 146 cases (69 .5%) with no associated co-morbidities while the second group 64 (30.5%) had co-morbidities such as obesity in 4 cases (1.9%), hypertension (HTN) in 24 cases (11.4%) cases, diabetes mellitus (DM) in 17 (8.1%) cases, history of recurrent stone surgery in 11 (5.2%) cases and more than one in 8 cases (3.8%). Co-morbidities, stone burden, location of stone, time of surgery, stay in the hospital, further operations, and negative events were among the reported data. Complications and the stone-free rate were the main outcome indicators. Results: Intraoperative complications were reported in 40 (18.8%) patients (18 group 1 and 22 group 2) during PCNL. Bleeding occurred in 22 (10.5%) patients (9 group 1 and 13 group 2), blood transfusions were needed in 4 (1.9%) (2 group 1 and 2 group 2), extravasation was observed in 11 patients (5.2%) (6 group 1 and 5 group 2) and cardiac arrhythmia in 3 (1.4%) (1 group 1 and 2 group 2) patients. Postoperative complications occurred in 61 patients (29%) (24 group 1 and 37 group 2) in the form of fever in 10 patients (4.8 %) (3 group 1 and 7 group 2) and prolonged leakage in 50 patients (23.8%) (21 group 1 and 29 group 2). One patient of group 2 died from postoperative sepsis. Extravasation and postoperative leakage were higher in diabetic patients than in non-diabetics. Stonefree rate was 60.5% (127 of 210). Clinically significant residual fragments (CSRFs) found in 70 cases (33.3%) (33 group 1 and 37 group 2). In 13 cases (6.2%) (5 group 1 and 8 group 2), clinically insignificant residual fragments (CIRFs) were found. In 8 (3 group 1 and 5 group 2) of the 13 cases, spontaneous stone passage was observed within 4-6 weeks of surgery. Residual stones in three cases (1 group 1 and 2 group 2) were asymptomatic and 4 mm or less, whereas stones increased in two cases of group 2. Among all factors studied, stone burden was significantly correlated to both intraoperative and postoperative complications. The occurrence of postoperative fever increased with large stone burden. Conclusions: PCNL is a therapeutic modality that is effective, feasible, and safe for a wide range of patients with concurrent medical issues. A steep curve is required to reduce intraoperative and postoperative complications
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