Solution of the Dirac equation in the rotating Bertotti-Robinson spacetime

The Dirac equation is solved in the rotating Bertotti-Robinson spacetime. The set of equations representing the Dirac equation in the Newman-Penrose formalism is decoupled into an axial and angular part. The axial equation, which is independent of mass, is solved exactly in terms of hypergeometric functions. The angular equation is considered both for massless (neutrino) and massive spin-(1/2) particles. For the neutrinos, it is shown that the angular equation admits an exact solution in terms of the confluent Heun equation. In the existence of mass, the angular equation does not allow an analytical solution, however, it is expressible as a set of first order differential equations apt for numerical study.Comment: 17 pages, no figure. Appeared in JMP (May, 2008

Efektivitas Penggunaan Modul Berbasis Lingkungan terhadap Hasil Belajar Peserta Didik Kelas VII SMP Negeri 28 Bulukumba

Penelitian ini bertujuan untuk mengetahui gambaran hasil belajar peserta didik Kelas VII A SMP Negeri 28 Bulukumba setelah diajar menggunakan modul berbasis lingkungan dan untuk mengetahui seberapa besar keefektifan penggunaan modul berbasis lingkungan terhadap hasil belajar peserta didik kelas VII A SMP Negeri 28 Bulukumba. Populasi dalam penelitian ini adalah seluruh peserta didik kelas VII SMP Negeri 28 Bulukumba tahun ajaran 2015/2016 yang terdiri dari 3 kelas dengan jumlah peserta didik 77, sampel sebanyak 24 sampel yang bertempat di kelas VII A. Instrumen penelitian yang digunakan dalam penelitian yaitu instrumen respon peserta didik terhadap modul dan instrumen tes hasil belajar. Skala yang digunakan untuk respon peserta didik terhadap modul yaitu skala Likert. Teknik analisis data yang digunakan yaitu analisis data statistik deskriptif dan inferensial. Hasil belajar peserta didik dengan modul fisika berbasis kontekstual mencapai nilai rata-rata 81,25. Rata-rata hasil belajar peserta didik termasuk kategori tinggi melebihi standar KKM yakni 70. Berdasarkan hasil uji hipotesis dengan menggunakan uji-t diperoleh nilai thitung > ttabel maka H0 ditolak sehingga Ha diterima. Dengan demikian dapat disimpulkan bahwa modul berbasis lingkungan efektif digunakan karena nilai hasil belajar peserta didik sebanyak 75% mencapai standar KKM

Investigation of the Effect of Pipeline Size on the Cross Flow Injection Process

Injection pumps constitute an essential component for many industrial applications. The main focus of this study is to predict the effect of the size of the pipeline on the cross flow injection process. A test-rig was designed, built and equipped with three different pipelines, 1½", ¾" and ½" diameters. Comparison was made under constant line pressure of 40-bar and line flow rate of 5 liter/min, with a fixed injection pump rotational speed of 100 rpm. The main parameter tested was the injection dose capacity at different pump displacements. Cross flow mixing process is also theoretically studied using 3D-CFD analysis to show the injection cross flow behavior for the same geometry and parameters used for experimental test. Results show that increasing the size of the pipeline increases injection pump doses ability. This effect is insignificant at lower injection pump displacements, while the effect of the size of the pipeline becomes dominant when increasing the displacement. By changing the size of the pipeline from ½" to 1½" diameter injection pump dose capacity increases by 3.24% at 100% pump displacement. Selecting larger pipe sizes for injection ports is recommended whenever possible

Risk Factors for Maternal Vitamin D Deficiency within the United Arab Emirates

Introduction: Vitamin D deficiency during pregnancy is a public health problem and it has been associated with negative pregnancy outcomes for both mothers and infants. Aim: To estimate the prevalence of vitamin D deficiency in pregnant women in the United Arab Emirates (UAE) and to identify the contribution of risk factors to the 25(OH)D levels. Methods: It is a cross-sectional study in which vitamin D levels of 1088 adult pregnant women were assessed. Information on vitamin D intake was available in a sub-sample of 266 women. Results: The mean serum 25(OH)D was 26.2 nmol/L (95% CI 25.2-27.1 range 5-129.1 nmol/L) with 69% of women being vitamin D deficient (<30 nmol/L). In the bivariate analysis, showed that no predictors could have been indicated as no values exceeded significance (p<0.2). Stepwise multiple linear regression analysis could not be applied to identify predictors of vitamin D levels as no values exceeded p=0.2. Conclusion: Due to the high prevalence of vitamin deficiency in UAE, there is an urge for interventions focusing on supplementation, fortification and diet diversity for preventing health consequences during a critical period of development

Supporting ultra poor people with rehabilitation and therapy among families of children with cerebral palsy in rural Bangladesh (SUPPORT CP) : Protocol of a randomised controlled trial

Introduction Poverty is a key contributor to delayed diagnosis and limited access to early intervention and rehabilitation for children with cerebral palsy (CP) in rural Bangladesh. 97% of families of children with CP live below the poverty line in Bangladesh. Therefore, in low-and middle-income countries (LMICs), efforts to improve outcomes for children with CP (including health-related quality of life, motor function, communication, and nutritional attainments) should also include measures to improve family economic and social capital. We propose a randomised controlled trial (RCT) to evaluate the effectiveness of an integrated microfinance/livelihood and community-based rehabilitation (IMCBR) program for ultra-poor families of children with CP in rural Bangladesh. Material and methods This will be a cluster RCT comparing three arms: (a) integrated microfinance/livelihood and community-based rehabilitation (IMCBR); (b) community-based rehabilitation (CBR) alone; and (c) care-as-usual (i.e. no intervention). Seven clusters will be recruited within each arm. Each cluster will consist of 10 child-caregiver dyads totalling 21 clusters with 210 dyads. Parents recruited in the IMCBR arm will take part in a microfinance/livelihood program and Parent Training Module (PTM), their children with CP will take part in a Goal Directed Training (GDT) program. The programs will be facilitated by specially trained Community Rehabilitation Officers. The CBR arm includes the same PTM and GDT interventions excluding the microfinance/livelihood program. The care-as-usual arm will be provided with information about early intervention and rehabilitation. The assessors will be blinded to group allocation. The duration of the intervention will be 12 months; outcomes will be measured at baseline, 6 months, 12 months, and 18 months. Conclusion This will be the first RCT of an integrated microfinance/livelihood and CBR program for children with CP in LMIC settings. Evidence from the study could transform approaches to improving wellbeing of children with CP and their ultra-poor families

First-in-human immunoPET imaging of COVID-19 convalescent patients using dynamic total-body PET and a CD8-targeted minibody

With most of the T cells residing in the tissue, not the blood, developing noninvasive methods for in vivo quantification of their biodistribution and kinetics is important for studying their role in immune response and memory. This study presents the first use of dynamic positron emission tomography (PET) and kinetic modeling for in vivo measurement of CD8+ T cell biodistribution in humans. A 89Zr-labeled CD8-targeted minibody (89Zr-Df-Crefmirlimab) was used with total-body PET in healthy individuals (N = 3) and coronavirus disease 2019 (COVID-19) convalescent patients (N = 5). Kinetic modeling results aligned with T cell-trafficking effects expected in lymphoid organs. Tissue-to-blood ratios from the first 7 hours of imaging were higher in bone marrow of COVID-19 convalescent patients compared to controls, with an increasing trend between 2 and 6 months after infection, consistent with modeled net influx rates and peripheral blood flow cytometry analysis. These results provide a promising platform for using dynamic PET to study the total-body immune response and memory

The association between different blood group systems and susceptibility to COVID-19: a single center cross-sectional study from Saudi Arabia

Background: Since the beginning of COVID-19 pandemic, many associated factors have been investigated to clarify the susceptibility and severity among the affected individuals. Biological markers can play an important role in identification of individual susceptibility to such pandemic. Growing evidence suggest the influence of different blood group systems on susceptibility to COVID-19 virus, with a particular blood type conferring selection advantage. Objectives: The study aimed to determine the association of ABO, Rhesus (D) and P1 blood groups with COVID-19 susceptibility in Taif city, Western Saudi Arabia. Methods: ABO, D and P1 blood antigens were determined in 104 blood samples of COVID-19 patients versus 100 control samples using either automated immunohematology analyser or test tube method. Statistical differences between patients and control samples were calculated based on p-value where results of ≤ 0.05 were considered significant. Results: O+ve blood group constituted the predominant type among the studied samples. Determination of P1 antigen showed significant association where Anti-P1 was positive in 76.9% of patients compared to 61.0% of controls with a P value of 0.01 conferring the susceptibility of P1+ve patients to COVID-19. Conclusion: Although our study showed no significant association between ABO and D, and susceptibility to COVID-19, there was a significant association between P1+ve and COVID-19. P1+ve participants were 2.131 times more associated with the risk of COVID-19 infection than those with Anti P1-ve. Thus, P1 antigen can be used as a biological marker for identification of individuals susceptibility to COVID-19. It is strongly advised that such individuals should consider extra protective measures.Further studies on other contributing factors should also be considered for more scientific clarity. Keywords: ABO Blood group; Rh(D); P1 antigen, COVID-19

Synthesis and Biocidal Activity of Some Naphthalene-Based Cationic Surfactants

In this study, different cationic surfactants were prepared by reacting dodecyl bromide with tertiary amines to produce a series of quaternary ammonium salts that were converted subsequently to stannous and cobalt cationic complexes via complexing them with stannous (II) or cobalt (II) ions. Surface properties such as surface- and interfacial-tension, and the emulsifying power of these surfactants were investigated. The surface parameters including critical micelle concentration, maximum surface excess, minimum surface area, tension lowering efficiency and effectiveness were studied. The free energy of micellization and adsorption were calculated. Antimicrobial activity was determined via the inhibition zone diameter of the prepared compounds, which was measured against six strains of a representative group of microorganisms. The antimicrobial activity of some of the prepared surfactants against sulfate reducing bacteria was determined by the dilution method. FTIR spectra, elemental analysis and a H1 NMR spectrum were examined to confirm compound structure and purity. The results obtained indicate that these compounds have good surface properties and good biocidal effect on broad spectrum of micro organisms

The solvation and dissociation of 4-benzylaniline hydrochloride in chlorobenzene

A reaction scheme is proposed to account for the liberation of 4-benzylaniline from 4-benzylaniline hydrochloride, using chlorobenzene as a solvent at a temperature of 373 K. Two operational regimes are explored: “closed” reaction conditions correspond to the retention of evolved hydrogen chloride gas within the reaction medium, whereas an “open” system permits gaseous hydrogen chloride to be released from the reaction medium. The solution phase chemistry is analyzed by 1H NMR spectroscopy. Complete liberation of solvated 4-benzylaniline from solid 4-benzylaniline hydrochloride is possible under “open” conditions, with the entropically favored conversion of solvated hydrogen chloride to the gaseous phase thought to be the thermodynamic driver that effectively controls a series of interconnecting equilibria. A kinetic model is proposed to account for the observations of the open system