Numerical simulation of electrophoresis separation processes

A new Petrov-Galerkin finite element formulation has been proposed for transient convection-diffusion problems. Most Petrov-Galerkin formulations take into account the spatial discretization, and the weighting functions so developed give satisfactory solutions for steady state problems. Though these schemes can be used for transient problems, there is scope for improvement. The schemes proposed here, which consider temporal as well as spatial discretization, provide improved solutions. Electrophoresis, which involves the motion of charged entities under the influence of an applied electric field, is governed by equations similiar to those encountered in fluid flow problems, i.e., transient convection-diffusion equations. Test problems are solved in electrophoresis and fluid flow. The results obtained are satisfactory. It is also expected that these schemes, suitably adapted, will improve the numerical solutions of the compressible Euler and the Navier-Stokes equations

Simulations of Gravitational Heating Due to Early Matter Domination

In cosmologies with an early matter-dominated era (EMDE) prior to Big Bang nucleosynthesis, the boosted growth of small-scale matter perturbations during the EMDE leads to microhalo formation long before halos would otherwise begin to form. For a range of models, halos can even form during the EMDE itself. These halos would dissipate at the end of the EMDE, releasing their gravitationally heated dark matter and thereby imprinting a free-streaming cut-off on the matter power spectrum. We conduct the first cosmological $N$-body simulations of the formation and evaporation of halos during and after an EMDE. We show that in these scenarios, the free-streaming cut-off after the EMDE can be predicted accurately from the linear matter power spectrum. Although the free streaming can erase much of the EMDE-driven boost to density perturbations, we use our findings to show that the (re-)formation of halos after the EMDE nevertheless proceeds before redshift $\sim 1000$. Early-forming microhalos are a key observational signature of an EMDE, and our prescription for the impact of gravitational heating will allow studies of the observational status and prospects of EMDE scenarios to cover a much wider range of parameters.Comment: 33 pages, 16 figures. Comments welcom

Second trimester placental thickness: its’ correlation with gestational age, femur length and biparietal diameter

Background: Placental thickness (PT) is the easiest placental dimension to measure, yet little is known about the normal PT. The aim of this study was to determine the normal, sonographically measured PT in millimetre (mm) in the second trimester and to determine if this measurement can be adjusted for gestational age for that time and evaluate its relationship with femur length and biparietal diameter of the fetus.Methods: The study was a cross sectional observational study, recruiting 100 consecutive, singleton pregnancies, reporting for ultrasonography (USG) between 14 weeks and 24 weeks of gestation, having undergone at least one ultrasonogram in the first trimester, with known last menstrual period (LMP). The placental thickness was measured perpendicular to the uterine wall, through the placenta at the site of cord insertion.Results: The average age of study population was 24.96 with a standard deviation (SD) of 2.70 years with the minimum age being 18 years and maximum age being 32 years. Regression analysis yielded the following mathematical relationships between PT, Gestational age (GA), Biparietal diameter (BPD) and Femur length (FL) in the second trimester. Y(PT)= 0.9366x (Gestation age)+1.655, R2 = 0.7332; Y(PT)= 0.2872x(BPD)+6.9578, R2= 0.7314; Y(PT)=0.2995x(FL)+ 10.03, R2 = 0.6186Conclusions: PT in present study showed a positive linear correlation with gestational age, FL and BPD in second trimester. Also, it can be concluded that PT may be used as a predictor of GA in women with unknown LMP

An Examination of the Flipped Classroom\u27s Efficacy on Post-Baccalaureate Pre-Medical Students

Existing flipped classroom (FC) research focuses on a typical, homogenous student population in terms of age. Research focuses on student satisfaction and perception of the FC to assess if student performance translates to actual perceived learning. Further, a growing number of studies show that outcomes of FC depend on student motivation. This study examines student performance, perception, and satisfaction in the FC in a novel demographic: Post-Baccalaureate Pre-Medical students. These students, who vary widely in age, experience, and prior knowledge of subject matter, are career changers who become full-time students to complete prerequisite coursework for medical school. Students enrolled in the undergraduate Biology course in GWU\u27s Post-Baccalaureate Pre-Medicine program were taught by the same instructor for this study. 17 students (Cohort 1), enrolled in 2017-2018, had a traditional classroom with a three hour didactic lecture. 30 students (Cohort 2), enrolled in 2018-2019, had the flipped classroom with 50% less didactic lecture time and more active and independent learning. End-of-course evaluations, pre and post quizzes, exam performance, and overall course grades were compared between cohorts. Course perceptions from evaluations were also compared, and Cohort 2 completed an additional survey on their perceptions of the FC. Results show that students were between ages 20 and 40 years of age for both cohorts. Student performance on exams and overall course grades did not vary significantly between the cohorts. FC components such as pre- and post- quizzes were perceived as significantly useful (p\u3c.01) and were often found to be engaging and most beneficial in promoting understanding. FC components viewed by students as really useful for exam preparation included pre-quizzes (68.96%), post-quizzes (82.75%), and jeopardy (51.72%). Components viewed by students as really useful for concept comprehension included pre-quizzes (42.85%), post-quizzes (57.14%), and questionnaire worksheets (58.62%). Group work was also viewed by 51.72% students as useful for concept comprehension. Student comments between cohorts indicated that students almost universally desired to maintain a lecture component to their learning. Surprisingly, course evaluation data further showed most students in both cohorts viewing lectures as contributing most to their learning over other class activities. This seems contrary to the majority of the current literature on student learning. These results suggest that student motivation and engagement are important factors in assessing student comprehension, and understanding the influence of these factors in learning methods could alter how instructors approach and effectively structure courses to increase student satisfaction

Carpal tunnel syndrome in females: pregnancy and lactation the major risk factors

Background: Carpal Tunnel Syndrome (CTS) is the most common entrapment neuropathy. CTS is more common in the age group of 45-65 years and more common in women than men.  Several factors cause CTS, including pregnancy and lactation.Methods: The study was conducted on 60 females with carpal tunnel syndrome. Each patient was subjected to detailed history and relevant clinical examination with emphasis on elaborate neurological examination. Informed consent regarding participation into the study was taken from the patients. Patients suspected of suffering from carpal tunnel syndrome were subjected to nerve conduction study. Patients were classified into mild- moderate and severe carpal tunnel syndrome according to clinical and nerve conduction grading.Results: Out of 60 females, 21 were pregnant (35%) and 19 were lactating (31.7%).  The mean age of presentation was 44.6±14.14 years with range from 22 to 63 years. Causes were attributed to Pregnancy (35%) lactation (31.7%), hypothyroidism (18.3%), occupational risk factors (15.85%) and gout (2.4%).Conclusions: Carpal tunnel syndrome has a high incidence in females. Sensory symptoms (paresthesia, numbness and nocturnal pain) were more common than symptoms of motor weakness. Dominant hand involvement was more common

Cornerstone of healthcare: awareness and compliance of patient safety measures in a large tertiary care hospital

Background: The study was done to assess the awareness and compliance of patient safety measures among healthcare providers and patients in a tertiary care hospital in India, ascertain the gap in both the aspects, if any and recommend the measures to improve the same.Methods: Cross sectional study in which patient safety survey was administered to random sample of 400 healthcare providers and 200 inpatients. The awareness was assessed through predefined questionnaires and compliance was assessed by observation, demonstration of processes, audit of patient files and interview of patients. Descriptive statistics analyzed with SPSS. Data was analyzed using frequencies, percentages and using Chi-square test.Results: The level of awareness was acceptable among healthcare providers, but the compliance was not satisfactory. Thus, gap was significant for certain parameters. The range of awareness among the patients was wide as study included patients of varying demographic and educational level. The range of compliance was also wide but was low. Thus, the gap was significant.Conclusions: As a result of continuous training of the healthcare providers, the awareness was satisfactory but on the other hand, they were not complying which may be due to workload, forgetfulness, lack of resources etc. On the other hand, the level of awareness was found to be low among patients and compliance was further lower down the ladder which may be due to difference in education, socioeconomic status, hesitation to enquire etc

Photo-induced volume changes in selenium. Tight-binding molecular dynamics study

Tight-binding molecular dynamics simulations of photo-excitations in small Se clusters (isolated Se$_8$ ring and helical Se chain) and glassy Se networks (containing 162 atoms) were carried out in order to analyse the photo induced instability inside the amorphous selenium. In the cluster systems after taking an electron from the highest occupied molecular orbital to the lowest unoccupied molecular orbital a bond breaking occurs. In the glassy networks photoinduced volume expansion was observed and at the same time the number of coordination defects changed significantly due to illumination

Is Nuchal Cord a Perfect Scapegoat: A Retrospective Analysis from Northwest India?

Background: Entanglement of the umbilical cord around the fetal neck (nuchal cord) is quite a common fi nding at delivery. It is often assumed that nuchal cord causes cord compression and thus low birth weight and intrapartum complications. Aim: The aim of this article is to study the eff ect of nuchal cord on the mode of delivery, complications and fetal outcome. Materials and Methods: A retrospective study was carried out on 386 deliveries, 60 of them with nuchal cord, during 1 year from November 2009 through October 2010. Their mode of delivery, complications and fetal outcome were studied and a comparison was established between nuchal cord group and the rest of the deliveries. Nuchal cord group was subdivided into loose nuchal cord (cord could easily be uncoiled before complete delivery of the baby) group and tight nuchal cord (cord was needed to be clamped and cut before delivery of the baby) group. Furthermore, the mode of delivery and fetal outcome were compared between these subgroups. Statistical analyses were performed using SPSS statistical soft ware version 12.0 (Chicago Illinios, USA). The results were expressed as percentages. Test for significance was done using Chi-square, and a P<0.05 was considered as significant.Results: The nuchal cord group did not have any signifi cant diff erence in the mode of delivery or fetal outcome compared with the control group. However, the subgroup having tight cord around the neck had significantly higher proportion of low Apgar scores and meconium staining at birth.Conclusions: Nuchal cord does not increase the chances of cesarean delivery. However, tight cord around the neck may result in low Apgar scores and increased incidence of fetal distress leading to cesarean section.  Keywords: Apgar score, cesarean delivery, meconium staining, north west India, nuchal cord, perinatal outcom

Investigating Methods of Transferring Tacit Knowledge among Nursing Experts of Iranian Hospitals

Nursing tacit knowledge is a knowledge that is produced inside the mind of nurses and not saved in any databases. The main challenge of nursing knowledge management is transferring tacit knowledge inside the mind of nurses to the others – especially scholars and researchers. This study evaluates personal, organizational, and technological factors affecting the tacit knowledge transfer among nursing experts. It also assesses the most important ways of tacit knowledge transfer among hospital nurses. This study applied survey method. The population was all nursing experts of Bushehr governmental hospitals nurses which were 480 and finally 215 nurses were selected as the sample. Data collection tool included a researcher-made questionnaire. Descriptive and analytical statistics tests were used. It was revealed that the most important way of tacit knowledge transfer among nursing experts was participating in continuing educational courses. Findings indicated that the most important personal factor affecting tacit knowledge transfer was job security; most important organizational factor was rewards system; and most important technological factor was independent physical environment and educational technologies