Effect of Polyvinylpyrrolidone on Vitrification of Buffalo (Bubalus bubalis) Oocytes

Vitrification, a method of rapid cooling, is an alternate cryopreservation method of oocytes and embryos. The present study was aimed to examine the effect of polyvinylpyrrolidone (PVP) on vitrification of buffalo oocytes. Cumulus oocyte complexes (COCs) with fully grown oocytes (120-130 µm in diameter) were aspirated from slaughtered buffalo ovaries for vitrification. COCs were treated with equilibration solution at room temperature for 5 min and then transferred to a vitrification solution for 1 min. Then the COCs were submerged into liquid nitrogen (-196̊C) for a while using cryotops. The COCs were thawed, diluted, and washed in a washing solution for 5 min, respectively. Vitrified oocytes were incubated for in vitro maturation (IVM) at 38.5̊C under an atmosphere of 5% CO2 in the air for 24 hrs. Cumulus cells surrounding the oocytes were removed mechanically, oocytes were fixed in acetic acid and ethanol, and stained with aceto-orcein to examine the meiotic stages of oocytes. The numbers of morphologically normal oocytes after vitrification were higher in 5% PVP than 0 and 10% PVP groups. A proportion of oocytes treated with 5% PVP reached the metaphase II (MII) stage while none of the oocytes from 0% and 10% PVP groupsdeveloped beyond anaphase I and metaphase I (MI) stages, respectively. These results show that PVP can be used as a cryoprotectant for the vitrification of buffalo oocytes

Wealth stratified inequalities in service utilisation of breast cancer screening across the geographical regions: A pooled decomposition analysis

Background Breast cancer is the most commonly occurring cancer among women in low-resourced countries. Reduction of its impacts is achievable with regular screening and early detection. The main aim of the study was to examine the role of wealth stratified inequality in the utilisation breast cancer screening (BCS) services and identified potential factors contribute to the observed inequalities. Methods A population-based cross-sectional multi-country analysis was used to study the utilisation of BCS services. Regression-based decomposition analyses were applied to examine the magnitude of the impact of inequalities on the utilisation of BCS services and to identify potential factors contributing to these outcomes. Observations from 140,974 women aged greater than or equal to 40 years were used in the analysis from 14 low-resource countries from the latest available national-level Demographic and Health Surveys (2008–09 to 2016). Results The population-weighted mean utilisation of BCS services was low at 15.41% (95% CI: 15.22, 15.60), varying from 80.82% in European countries to 25.26% in South American countries, 16.95% in North American countries, 15.06% in Asia and 13.84% in African countries. Women with higher socioeconomic status (SES) had higher utilisation of BCS services (15%) than those with lower SES (9%). A high degree of inequality in accessing and the use of BCS services existed in all study countries across geographical areas. Older women, access to limited mass media communication, being insured, rurality and low wealth score were found to be significantly associated with lower utilisation of BCS services. Together they explained approximately 60% in the total inequality in utilisation of BCS services. Conclusions The level of wealth relates to the inequality in accessing BCS amongst reproductive women in these 14 low-resource countries. The findings may assist policymakers to develop risk-pooling financial mechanisms and design strategies to increase community awareness of BCS services. These strategies may contribute to reducing inequalities associated with achieving higher rates of the utilisation of BCS services

Slow-light enhanced light-matter interactions with applications to gas sensing

Optical gas detection in microsystems is limited by the short micron scale optical path length available. Recently, the concept of slow-light enhanced absorption has been proposed as a route to compensate for the short path length in miniaturized absorption cells. We extend the previous perturbation theory to the case of a Bragg stack infiltrated by a spectrally strongly dispersive gas with a narrow and distinct absorption peak. We show that considerable signal enhancement is possible. As an example, we consider a Bragg stack consisting of PMMA infiltrated by O2. Here, the required optical path length for visible to near-infrared detection (~760 nm) can be reduced by at least a factor of 10^2, making a path length of 1 mm feasible. By using this technique, optical gas detection can potentially be made possible in microsystems

Masters and Doctor of Philosophy admission prediction of Bangladeshi students into different classes of universities

Many Bangladeshi students intend to pursue higher studies abroad after completing their undergraduate degrees every year. Choosing a university for higher education is a challenging task for students. Especially, the students with average and lower academic credentials (undergraduate grades, English proficiency test scores, job, and research experiences) can hardly choose the universities that could match their profile. In this paper, we have analyzed some real unique data of Bangladeshi students who had been accepted admissions at different universities worldwide for higher studies. Finally, we have produced prediction models based on random forest (RF) and decision tree (DT) techniques, which can predict appropriate universities of specific classes for students according to their past academic performances. Two separate models have been studied in this paper, one for Masters (MS)students and another for Doctor of Philosophy (PhD)students. According to the Quacquarelli Symonds (QS) World University Rankings, the universities where the students got admitted have been divided into 9 classes for MS students and 8 classes for PhD students. Accuracy, precision, recall and F1-Score have been studied for the two machine learning algorithms. Numerical results show that both the algorithm DT and RF have the same accuracy of 89% for PhD student data and 86% for MS student data

Inspection of defect-induced mode coupling in hollow-core photonic bandgap fibers using time-of-flight

We analyze defect-induced mode coupling in a hollow-core photonic bandgap fiber using time-of-flight, and show its utility in complementing optical time-domain reflectometry

Brane-bulk energy exchange : a model with the present universe as a global attractor

The role of brane-bulk energy exchange and of an induced gravity term on a single braneworld of negative tension and vanishing effective cosmological constant is studied. It is shown that for the physically interesting cases of dust and radiation a unique global attractor which can realize our present universe (accelerating and 0<Omega_{m0}<1) exists for a wide range of the parameters of the model. For Omega_{m0}=0.3, independently of the other parameters, the model predicts that the equation of state for the dark energy today is w_{DE,0}=-1.4, while Omega_{m0}=0.03 leads to w_{DE,0}=-1.03. In addition, during its evolution, w_{DE} crosses the w_{DE}=-1 line to smaller values.Comment: 8 pages, 2 figures, RevTex; references added, to appear in JHE

30.7 Tb/s (96x320 Gb/s) DP-32QAM transmission over 19-cell photonic band gap fiber

We report for the first time coherently-detected, polarization-multiplexed transmission over a photonic band gap fiber. By transmitting 96 x 320-Gb/s DP-32QAM modulated channels, a net data rate of 24 Tb/s was obtained

Hollow core fibres for high capacity data transmission

We review our progress in developing, characterizing and handling hollow-core photonic bandgap fibers with improved transmission properties, targeted at high-capacity, low-latency data transmission in the current telecoms window and at the potentially lower-loss 2µm wavelengths

Lattice QCD Simulations in External Background Fields

We discuss recent results and future prospects regarding the investigation, by lattice simulations, of the non-perturbative properties of QCD and of its phase diagram in presence of magnetic or chromomagnetic background fields. After a brief introduction to the formulation of lattice QCD in presence of external fields, we focus on studies regarding the effects of external fields on chiral symmetry breaking, on its restoration at finite temperature and on deconfinement. We conclude with a few comments regarding the effects of electromagnetic background fields on gluodynamics.Comment: 31 pages, 10 figures, minor changes and references added. To appear in Lect. Notes Phys. "Strongly interacting matter in magnetic fields" (Springer), edited by D. Kharzeev, K. Landsteiner, A. Schmitt, H.-U. Ye

How close can an Inhomogeneous Universe mimic the Concordance Model?

Recently, spatially inhomogeneous cosmological models have been proposed as an alternative to the LCDM model, with the aim of reproducing the late time dynamics of the Universe without introducing a cosmological constant or dark energy. This paper investigates the possibility of distinguishing such models from the standard LCDM using background or large scale structure data. It also illustrates and emphasizes the necessity of testing the Copernican principle in order to confront the tests of general relativity with the large scale structure.Comment: 15 pages, 7 figure