19 research outputs found
The Evolution of Compact Binary Star Systems
We review the formation and evolution of compact binary stars consisting of
white dwarfs (WDs), neutron stars (NSs), and black holes (BHs). Binary NSs and
BHs are thought to be the primary astrophysical sources of gravitational waves
(GWs) within the frequency band of ground-based detectors, while compact
binaries of WDs are important sources of GWs at lower frequencies to be covered
by space interferometers (LISA). Major uncertainties in the current
understanding of properties of NSs and BHs most relevant to the GW studies are
discussed, including the treatment of the natal kicks which compact stellar
remnants acquire during the core collapse of massive stars and the common
envelope phase of binary evolution. We discuss the coalescence rates of binary
NSs and BHs and prospects for their detections, the formation and evolution of
binary WDs and their observational manifestations. Special attention is given
to AM CVn-stars -- compact binaries in which the Roche lobe is filled by
another WD or a low-mass partially degenerate helium-star, as these stars are
thought to be the best LISA verification binary GW sources.Comment: 105 pages, 18 figure
Gene Expression Signature in Peripheral Blood Detects Thoracic Aortic Aneurysm
BACKGROUND: Thoracic aortic aneurysm (TAA) is usually asymptomatic and associated with high mortality. Adverse clinical outcome of TAA is preventable by elective surgical repair; however, identifying at-risk individuals is difficult. We hypothesized that gene expression patterns in peripheral blood cells may correlate with TAA disease status. Our goal was to identify a distinct gene expression signature in peripheral blood that may identify individuals at risk for TAA. METHODS AND FINDINGS: Whole genome gene expression profiles from 94 peripheral blood samples (collected from 58 individuals with TAA and 36 controls) were analyzed. Significance Analysis of Microarray (SAM) identified potential signature genes characterizing TAA vs. normal, ascending vs. descending TAA, and sporadic vs. familial TAA. Using a training set containing 36 TAA patients and 25 controls, a 41-gene classification model was constructed for detecting TAA status and an overall accuracy of 78+/-6% was achieved. Testing this classifier on an independent validation set containing 22 TAA samples and 11 controls yielded an overall classification accuracy of 78%. These 41 classifier genes were further validated by TaqMan real-time PCR assays. Classification based on the TaqMan data replicated the microarray results and achieved 80% classification accuracy on the testing set. CONCLUSIONS: This study identified informative gene expression signatures in peripheral blood cells that can characterize TAA status and subtypes of TAA. Moreover, a 41-gene classifier based on expression signature can identify TAA patients with high accuracy. The transcriptional programs in peripheral blood leading to the identification of these markers also provide insights into the mechanism of development of aortic aneurysms and highlight potential targets for therapeutic intervention. The classifier genes identified in this study, and validated by TaqMan real-time PCR, define a set of promising potential diagnostic markers, setting the stage for a blood-based gene expression test to facilitate early detection of TAA
Does electrification spur the fertility transition? evidence from Indonesia
We analyze various pathways through which access to electricity affects fertility in Indonesia, using a district difference-in-difference approach. The electrification rate increased by 65 % over the study period, and our results suggest that the subsequent effects on fertility account for about 18 % to 24 % of the overall decline in fertility. A key channel is increased exposure to television. Using in addition several waves of Demographic and Health Surveys, we find suggestive evidence that increased exposure to TV affects, in particular, fertility preferences and increases the effective use of contraception. Reduced child mortality seems to be another important pathway
The Added Value of Understanding Informal Social Networks in an Adaptive Capacity Assessment: Explorations of an Urban Water Management System in Indonesia
Towards identifying dyslexia in Standard Indonesian: the development of a reading assessment battery
Strategy for large???scale monolithic Perovskite/Silicon tandem solar cell: A review of recent progress
For any solar cell technology to reach the final mass-production/commercialization stage, it must meet all technological, economic, and social criteria such as high efficiency, large-area scalability, long-term stability, price competitiveness, and environmental friendliness of constituent materials. Until now, various solar cell technologies have been proposed and investigated, but only crystalline silicon, CdTe, and CIGS technologies have overcome the threshold of mass-production/commercialization. Recently, a perovskite/silicon (PVK/Si) tandem solar cell technology with high efficiency of 29.1% has been reported, which exceeds the theoretical limit of single-junction solar cells as well as the efficiency of stand-alone silicon or perovskite solar cells. The International Technology Roadmap for Photovoltaics (ITRPV) predicts that silicon-based tandem solar cells will account for about 5% market share in 2029 and among various candidates, the combination of silicon and perovskite is the most likely scenario. Here, we classify and review the PVK/Si tandem solar cell technology in terms of homo- and hetero-junction silicon solar cells, the doping type of the bottom silicon cell, and the corresponding so-called normal and inverted structure of the top perovskite cell, along with mechanical and monolithic tandemization schemes. In particular, we review and discuss the recent advances in manufacturing top perovskite cells using solution and vacuum deposition technology for large-area scalability and specific issues of recombination layers and top transparent electrodes for large-area PVK/Si tandem solar cells, which are indispensable for the final commercialization of tandem solar cells
Pembiyaan Mudharabah Terhadap Return on Investment: Studi Kasus pada Bank Mandiri Syariah Kuningan
Pembiyaan Mudharabah Terhadap Return on Investment: Studi Kasus pada Bank Mandiri Syariah Kuningan
Tujuan penelitian ini untuk mengetahui seberapa besar pendapatan bagi hasil pembiayaan mudharabah, untuk mengetahui tingkat return on investment, dan untuk mengetahui seberapa besar pengaruh pembiayaan mudharabah terhadap return on investment dari tahun ke tahunnya selama 7 tahun terakhir. Penelitian ini menggunakan pendekatan deskriptif kuantitatif. Objek penelitian ini yaitu pada Bank Syariah Mandiri Kuningan. Jenis penelitian yang digunakan merupakan penelitian yang menggunakan angka, mulai dari pengumpulan data, penafsiran terhadap data tersebut, serta penampilan dari hasilnya. Penelitian kuantitatif juga disertai dengan tabel, grafik, bagan, gambar atau tampilan lain. Berdasarkan hasil penelitian yang dibantu dengan program SPSS 21.0, dengan menggunakan uji Regresi Linier Sederhana dengan menghasilkan Y = -1.232+0,554X diinterpretasikan adanya hubungan positif antara pembiayaan mudharabah dengan return on investment, dengan korelasi sebesar 0,703 yang berarti hubungannya sangat kuat, dan koefisien determinasi 0,494 yang dapat diartikan pengaruh pembiayaan mudharabah terhadap return on investent adalah 49,4% sedangkan sisanya sebesar 50,6% dipengaruhi oleh faktor lain yang tidak diteliti dalam penelitian ini