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Energy absorption by matter is fundamental to natural and man-made processes. However, despite this ubiquity, developing materials capable of withstanding severe energy fluxes without degradation is a significant challenge in materials science and engineering. Despite recent advances in creating alloys resistant to energy fluxes, mitigating the damage caused by the absorption and transfer of mechanical energy remains a critical obstacle in both fundamental science and technological applications. This challenge is especially prominent when the mechanical energy is transferred to the material by shock loading. This study demonstrates a phenomenon in which microstructurally stabilized nanocrystalline Cu-Ta alloys can undergo reversal or nearly complete recovery of the dislocation structure after multiple shock-loading impacts, unlike any other known metallic material. The microstructure of these alloys can withstand repeated shock-wave interactions at pressures up to 12 GPa without any significant microstructural damage or deterioration, demonstrating an extraordinary capacity to be virtually immune to the detrimental effects of shock loading. This study reveals that under 12 GPa shock loading, stabilized nanocrystalline Cu-3Ta can generate and reabsorb dislocations, enabling near-complete recovery without microstructural deterioration. This behavior contrasts with other known metals. [ABSTRACT FROM AUTHOR]

Background: Domestic violence (DV) prior to, and during pregnancy is associated with increased risks for morbidity and mortality. As pregnant women routinely attend antenatal care this environment can be used to offer support to women experiencing DV. We have developed a video intervention that focuses on the use of behavioral coping strategies, particularly regarding disclosure of DV experiences. The effectiveness of this intervention will be evaluated through a randomized controlled trial (RCT) and a concurrent process evaluation. Methods: All pregnant women between 12–22 weeks of gestation attending routine antenatal care at two tertiary level hospitals in Nepal are invited to participate. DV is measured using the Nepalese version of the Abuse Assessment Screen (N-AAS). Additionally, we measure participants' mental health, use of coping strategies, physical activity, and food security through a Color-coded Audio Computer Assisted Self Interview (C-ACASI). Irrespective of DV status, women are randomized into the intervention or control arm using a computer-generated randomization program. The intervention arm views a short video providing information on DV, safety improving actions women can take with an emphasis on disclosing the violence to a trusted person along with utilizing helplines available in Nepal. The control group watches a video on maintaining a healthy pregnancy and when to seek healthcare. The primary outcome is the proportion of women disclosing their DV status to someone. Secondary outcomes are symptoms of anxiety and depression, coping strategies, the use of safety measures and attitudes towards acceptance of abuse. Follow-up is conducted after 32 weeks of gestation, where both the intervention and control group participants view the intervention video after completing the follow-up questionnaire. Additionally, a mixed methods process evaluation of the intervention will be carried out to explore factors influencing the acceptability of the intervention and the disclosure of DV, including a review of project documents, individual interviews, and focus group discussions with members of the research team, healthcare providers, and participants. Discussion: This study will provide evidence on whether pregnant women attending regular antenatal visits can enhance their safety by disclosing their experiences of violence to a trusted person after receiving a video intervention. Trial registration: The study is registered in ClinicalTrial.gov with identifier NCT05199935. [ABSTRACT FROM AUTHOR]

Immiscible Cu-Ta alloys produced by mechanical alloying are currently the subject of intensive research due to their mechanical strength combined with extraordinary structural stability at high temperatures. Previous experimental and simulation studies suggested that grain boundaries (GBs) in Cu-Ta alloys are stabilized by Ta nano-clusters coherent with the Cu matrix. To better understand the stabilization effect of Ta, we performed atomistic computer simulations of GB-cluster interactions in Cu-Ta alloys with various compositions and GB velocities. The study focuses on a single plane GB driven by an applied shear stress due to the shear-coupling effect. The results of the simulations are in close quantitative agreement with the Zener model of GB pinning. This agreement and the large magnitude of the unpinning stress confirm that the structural stability of these alloys is due to the drastically decreased GB mobility rather than a reduction in GB energy. For comparison, we simulated GB motion in a random solid solution. While the latter also reduces the GB mobility, the effect is not as strong as in the presence of Ta clusters. GB motion in the random solution itself induces precipitation of Ta clusters due to short-circuit diffusion of Ta in GBs, suggesting a possible mechanism of cluster formation inside the grains. [ABSTRACT FROM AUTHOR]

Aims: This study evaluates the effectiveness of usage of 0.2 mg intrathecal morphine as post-operative analgesia and its effect on activity of mother after elective cesarean section. Methods: This hospital based prospective, randomized, double-blinded and placebo controlled study was carried out at Nagarik Community Teaching Hospital, Bhaktapur between 2012 January to 2014 November after the approval was taken from the hospital authority and the written informed consent from the participating patients. Fifty women of ASA I or II physical status undergoing cesarean section under sub-arachnoid block was randomized into two groups - P group (placebo group, n = 25) and M group (Treatment group, n = 25). P Group received hyperbaric bupivacaine 2.3ml, 0.5% bupivacaine (11.5 mg) and M Group received morphine 0.2 ml (0.2 mg) plus bupivacaine 2.3ml, 0.5% (11.5 mg) intrathecally. All subjects received 8 mg ondansetron intravenously 30 minutes before surgery to prevent possible drug-induced pruritus and postoperative nausea and vomiting. 1000 mg rectal acetaminophen suppository was given at the end of the surgery. Pain, nausea and pruritus during the first 24 hours using visual analog scale were recorded by a trained nurse or attending doctor who was not involved in the study. Results: Duration of complete analgesia and the time to request for additional analgesics was longer in M Group than in P Group. Similarly, the active movement is earlier in M Group than in P Group. There were no significant differences in adverse effects between the groups. Conclusions: Addition of morphine 0.2 mg to heavy bupivacaine intrathecally reduced post-operative pain and analgesic requirements without any significant difference in adverse effects. [ABSTRACT FROM AUTHOR]

Introduction: Chronic obstructive pulmonary disease (COPD) remains a major public health problem. Many patients suffering from chronic obstructive lungs diseases are of poor economic status, mostly illiterate, therefore has a direct bearing on patient compliance. Tiotropium is a new anticholinergic therapy for chronic obstructive pulmonary disease that differs from ipratropium by its functional relative selectively for musarinic receptor subtypes and which allows single dosing a day. This study presents a cost-effectiveness, efficacy, and side-effects of Ipratropium bromide and Tiotropium in COPD. Methods: Prospective study was conducted In Kathmandu University Teaching Hospital, between the year 2008 and 2009 in terms of cost-effectiveness, efficacy, and side-effects of Tiotropium and Ipratropium amongst COPD patients. Results: Tiotropium and Ipratropium were prescribed in total of 57 patients (30 in ipratropium bromide and 27 in tiotropium bromide) for the management of COPD among outpatients. There were no significant differences in age, height, weight and baseline lung function parameters (FEV1 and PEF) between the two drugs i.e. ipratropium bromide and tiotropium bromide. Significant improvement in lung function parameters were found in each respective group of drugs after bronchodilator therapy. Tiotropium results in significant reduction of Chronic Obstructive Pulmonary disease exacerbations and significant improvement in quality of life, lung function, and dyspnoea compared to ipratropium. The additional cost to achieve these favorable outcomes was cheaper than Ipratropium bromide. (Nepalese Rs. 7.03 per day for tiotropium as compared to Rs. 9.06 for Ipratropium) Conclusions: Tiotropium results in significant reduction of chronic obstructive pulmonary disease exacerbations and significant improvement in quality of life, lung function and dyspnoea compared to Ipratropium. [ABSTRACT FROM AUTHOR]

Molecular dynamics (MD) simulations are applied to study solute drag by curvature-driven grain boundaries (GBs) in Cu–Ag solid solution. Although lattice diffusion is frozen on the MD timescale, the GB significantly accelerates the solute diffusion and alters the state of short-range order in lattice regions swept by its motion. The accelerated diffusion produces a nonuniform redistribution of the solute atoms in the form of GB clusters enhancing the solute drag by the Zener pinning mechanism. This finding points to an important role of lateral GB diffusion in the solute drag effect. A 1.5 at.%Ag alloying reduces the GB free energy by 10–20% while reducing the GB mobility coefficients by more than an order of magnitude. Given the greater impact of alloying on the GB mobility than on the capillary driving force, kinetic stabilization of nanomaterials against grain growth is likely to be more effective than thermodynamic stabilization aiming to reduce the GB free energy. [ABSTRACT FROM AUTHOR]

Aims: This study aims to determine the frequency of near-miss obstetric events and analyze its nature such as reasons for nearmiss, organ dysfunction associated and critical management required among pregnant women managed over a 3-year period in a Tertiary Care Teaching Hospital in Nepal. Methods: This hospital based prospective, descriptive study was done from August 2011 to February 2015. Case eligibility was defined by WHO Near-Miss Guidelines. Medical records of the patients and the interview with the patient, accompanying family members and health workers from referral centres were used to generate the data which were filled in the pre-designed questionnaire. The data generated and analyzed included age and gestation weeks, parity, mode of intervention, associated organ dysfunctions, reasons for near-miss and critical intervention accompanied to manage the near-miss cases. Results were presented in mean ± SD and percentages, wherever applicable. Results: There were 4617 deliveries with 28 near-miss cases. The major factors contributing near-miss events were obstetric haemorrhage followed by hypertensive disorder. Three fourth (n=21) of cases required blood transfusion and almost all cases (n=26) required ICU management. Coagulation disorder was observed in majority of cases (n=23) followed by cardiovascular, respiratory and uterine atony. Conclusions: In this study, maternal near-miss event was mainly attributable to obstetric haemorrhage followed by hypertension and sepsis. Major organ-system disorders observed were coagulation disorder, cardiovascular, respiratory and uterine disorders. Almost all the cases were managed in ICU and majority of them required blood transfusion. [ABSTRACT FROM AUTHOR]