Quench simulation of superconducting magnets with commercial multi-physics software

The simulation of quenches in superconducting magnets is a multiphysics problem of highest complexity. Operated at 1.9 K above absolute zero, the material properties of superconductors and superfluid helium vary by several orders of magnitude over a range of only 10 K. The heat transfer from metal to helium goes through different transfer and boiling regimes as a function of temperature, heat flux, and transferred energy. Electrical, magnetic, thermal, and fluid dynamic effects are intimately coupled, yet live on vastly different time and spatial scales. While the physical models may be the same in all cases, it is an open debate whether the user should opt for commercial multiphysics software like ANSYS or COMSOL, write customized models based on general purpose network solvers like SPICE, or implement the physics models and numerical solvers entirely in custom software like the QP3, THEA, and ROXIE codes currently in use at the European Organisation for Nuclear Research (CERN). Each approach has its strengths and limitations, some related to performance, others to usability and maintainability, and others again to the flexibility of material parameterizations. In this context the master thesis mainly involves the study of the strengths and limitations of the first approach. The primary goal of the thesis is to build a 1D numerical model representing a superconducting wire based on existing physical models. An adiabatic model has been constructed, to solve one of the five boundary value problems involved in the quench, both in ANSYS and in COMSOL. The temperature dependent material properties and loads are defined using function tools in COMSOL and by creating look up tables in ANSYS. The models were validated with QP3 and compared in terms of performance, stability and accuracy. The helium-cooled model is built only in ANSYS. The model solves two of the five boundary value problems simultaneously as a coupled problem. Apart from generic numerical code (transient thermal analysis), a separate algorithm is needed to define the non-linear heat transfer between the metal and the helium. For this ANSYS Parametric Design Language (APDL) scripts are used. During the analysis the ANSYS transient thermal codes are executed several times within a loop. There are three different types of helium cooled models. All models were validated with QP3. The results obtained from comparisons show that the adiabatic models were able to simulate quenches with the desired accuracy. The adiabatic analysis in the commercial simulation tools is more efficient and stable for various scale of spatial discretization. Similarly, the helium-cooled models are able to simulate quenches with satisfactory accuracy. Nevertheless, the models are not compatible with automatic time stepping method of the simulation environment. The use of fixed time stepping method in the models resulted the coupled analysis in ANSYS to be far more time consuming than in QP3

Seroprevalence and Risk Factors of Infectious Bovine Rhinotracheitis in Dairy Cattle of Chitwan, Nawalpur and Rupandehi Districts of Nepal

The cross-sectional study from July 2018 to September 2018 was conducted to determine the seroprevalence and risk factors of Infectious Bovine Rhinotracheitis (IBR) in cattle of the Chitwan, Nawalpur, and Rupandehi districts of Nepal. The existence of antibodies against IBR was investigated in 92 serum samples obtained systematically from 55 cattle herds using Indirect-ELISA. A questionnaire interview was done to collect individual and herd-level data. The association between categorical variables and the outcome variable (seropositive) was assessed by bivariate analysis and multivariate logistic regression analysis in SPSS version 19.0. The seroprevalence of IBR was 18.48% (95% CI: 11.1-27.9), and district, breed, and herd size were identified as potential risk factors for IBR seropositivity. Significantly higher risk for IBR was found in Chitwan (Percentage-Positive “PP” = 36.37%; Odd ratio “OR” = 5.211; p = 0.008) than in Nawalpur (PP = 9.38%; OR = 0.931) and Rupandehi (PP = 10.00%). PP of IBR was significantly higher in Jersey crosses (PP = 30.00%; OR = 2.893; p = 0.048) than Holstein Friesian crosses (PP = 12.90%). Similarly, herds with more than 10 cattle (PP = 33.33%; OR = 4.167; p = 0.042) were found significantly at higher odds for seropositivity than herds having less than 10 cattle (PP = 10.71%). Due to the moderate prevalence of IBR among cattle in Nepal, this study recommends conducting additional planned research on IBR at the national level to safeguard the country's dairy businesses from potential financial losses

Neonatal health in Nepal: analysis of absolute and relative inequalities and impact of current efforts to reduce neonatal mortality

Background: Nepal has made substantial progress in reducing under-five mortality and is on track to achieve Millennium Development Goal 4, but advances in neonatal health are less encouraging. The objectives of this study were to assess relative and absolute inequalities in neonatal mortality over time, and to review experience with major programs to promote neonatal health. Methods: Using four nationally representative surveys conducted in 1996, 2001, 2006 and 2011, we calculated neonatal mortality rates for Nepal and for population groups based on child sex, geographical and socio-economic variables using a true cohort log probability approach. Inequalities based on different variables and years were assessed using rate differences (rd) and rate ratios (rr); time trends in neonatal mortality were measured using the annual rate of reduction. Through literature searches and expert consultation, information on Nepalese policies and programs implemented since 1990 and directly or indirectly attempting to reduce neonatal mortality was compiled. Data on timeline, coverage and effectiveness were extracted for major programs. Results: The annual rate of reduction for neonatal mortality between 1996 and 2011 (2.8 percent per annum) greatly lags behind the achievements in under-five and infant mortality, and varies across population groups. For the year 2011, stark absolute and relative inequalities in neonatal mortality exist in relation to wealth status (rd = 21.4, rr = 2.2); these are less pronounced for other measures of socio-economic status, child sex and urban-rural residence, ecological and development region. Among many efforts to promote child and maternal health, three established programs and two pilot programs emerged as particularly relevant to reducing neonatal mortality. While these were designed based on national and international evidence, information about coverage of different population groups and effectiveness is limited. Conclusion: Neonatal mortality varies greatly by socio-demographic variables. This study clearly shows that much remains to be achieved in terms of reducing neonatal mortality across different socio-economic, ethnic and geographical population groups in Nepal. In moving forward it will be important to scale up programs of proven effectiveness, conduct in-depth evaluation of promising new approaches, target unreached and hard-to-reach populations, and maximize use of financial and personnel resources through integration across programs

Antibiotic Susceptibility Profile of respiratory pathogens obtained at tertiary care hospital from western Nepal

The prevalence and drug resistance of the respiratory pathogens is increasing gradually in Nepal. However, their detail study is rare in the western region of Nepal. Hence, this study was carried out to know the incidence and antibiotic susceptibility profile of the respiratory pathogens obtained at a tertiary care center located at Pokhara. 139 pathogens were isolated from 460 clinical samples included. Significant pathogens were Gram-negative bacteria 94 (67.62%), followed by 28 (20.15%) Candida, and Gram-positive isolates 17 (12.23%). The growth rate was significantly higher for sputum samples in comparison to throat swabs. Pseudomonas aeruginosa, Klebsiella pneumoniae, and Acinetobacter were significant Gram-negative isolates while Staphylococcus aureus, Streptococcus pneumoniae, and Streptococcus pyogenes were Gram-positive pathogens. Sensitivity rate was higher for colistin and imipenem among Gram-negative isolates while lower sensitivity was for cefepime. Vancomycin was effective against all tested Gram-positive isolates while erythromycin and ciprofloxacin were less effective

Impact of the community-based newborn care package in Nepal: a quasi-experimental evaluation

OBJECTIVE To evaluate the impact of the community-based newborn care package (CBNCP) on six essential practices to improve neonatal health. METHODS CBNCP pilot districts were matched to comparison districts using propensity scores. Impact on birth preparedness, antenatal care seeking, antenatal care quality, delivery by skilled birth attendant, immediate newborn care and postnatal care within 48 hours were assessed using Demographic and Health Survey (DHS) and Health Management Information System (HMIS) data through difference-in-differences and multivariate logistic regression analyses. FINDINGS Changes over time in intervention and comparison areas were similar in difference-in-differences analysis of DHS and HMIS data. Logistic regression of DHS data also did not reveal any significant improvement in combined outcomes: birth preparedness, adjusted OR (aOR)=0.8 (95% CI 0.4 to 1.7); antenatal care seeking, aOR=1.0 (0.6 to 1.5); antenatal care quality, aOR=1.4 (0.9 to 2.1); delivery by skilled birth attendant, aOR=1.5 (1.0 to 2.3); immediate newborn care, aOR=1.1 (0.7 to 1.9); postnatal care, aOR=1.3 (0.9 to 1.9). Health providers' knowledge and skills in intervention districts were fair but showed much variation between different providers and districts. CONCLUSIONS This study, while representing an early assessment of impact, did not identify significant improvements in newborn care practices and raises concerns regarding CBNCP implementation. It has contributed to revisions of the package and it being merged with the Integrated Management of Neonatal and Childhood Illness programme. This is now being implemented in 35 districts and carefully monitored for quality and impact. The study also highlights general challenges in evaluating the impacts of a complex health intervention under 'real life' conditions

Analysis of cardiac autonomic modulation in normotensive obese and eutrophic adults of Nepal

Background: Obese people have a higher prevalence of cardiovascular disease, though unknown mechanism, supposed to be due to autonomic dysfunction which is still in controversy. This study aimed to assess and compare heart rate variability (HRV) between normotensive obese and adults.Methods: The study was conducted on 30 normotensive obese adults (mean age 32.07±7.25 years) with BMI>30 and 29 age- and sex-matched normal weight controls (mean age 30.48±8.01 years) with BMI: 18-24 Kg/m2. Short-term HRV variables were assessed using standard protocol. The data were compared between the groups using Mann Whitney ‘U’ test.Results: In obese group, there was significant increase in the mean heart rate [79.17±8.80 Vs 71.48±8.41 beats/min, p=0.001], systolic blood pressure [121.20±9.89 Vs 113.24±11.07, mmHg, p=0.004] and diastolic blood pressure [84.97±7.87 Vs 74.83±10.31 mmHg, p=0.000]. The HRV parasympathetic indicators were less [RMSSD {28.75(16.72-38.35) Vs 41.55(30.6-56.75) ms, p=0.018}, NN50 {15.5(2-39) Vs 83.5(32.75-116.25), p=0.010}], and sympathetic indicator LF/HF ratio [1.2(0.65-2.20) Vs 0.79(0.5-1.02), p=0.004] was more in obese group.Conclusions: Obese persons have increased sympathetic activity with a reduction in parasympathetic (vagal) tone indicating poor autonomic cardiac rhythm control. Moreover, the altered autonomic activity could be the reason for increased mean heart rate and blood pressures in normotensive obese persons

EN-BIRTH Data Collector Training - Handbook and Manual

The EN-BIRTH study aims to validate selected newborn and maternal indicators for routine facility-based tracking of coverage and quality of care for use at district, national and global levels. The item contains the EN-BIRTH_Trainer's Manual (14 June 2017) and EN-BIRTH_Training Handbook (23 May 2017)