3,927 research outputs found
Optimization of miRNA-seq data preprocessing.
The past two decades of microRNA (miRNA) research has solidified the role of these small non-coding RNAs as key regulators of many biological processes and promising biomarkers for disease. The concurrent development in high-throughput profiling technology has further advanced our understanding of the impact of their dysregulation on a global scale. Currently, next-generation sequencing is the platform of choice for the discovery and quantification of miRNAs. Despite this, there is no clear consensus on how the data should be preprocessed before conducting downstream analyses. Often overlooked, data preprocessing is an essential step in data analysis: the presence of unreliable features and noise can affect the conclusions drawn from downstream analyses. Using a spike-in dilution study, we evaluated the effects of several general-purpose aligners (BWA, Bowtie, Bowtie 2 and Novoalign), and normalization methods (counts-per-million, total count scaling, upper quartile scaling, Trimmed Mean of M, DESeq, linear regression, cyclic loess and quantile) with respect to the final miRNA count data distribution, variance, bias and accuracy of differential expression analysis. We make practical recommendations on the optimal preprocessing methods for the extraction and interpretation of miRNA count data from small RNA-sequencing experiments
SME Access to Credit
The aim of this paper is to inform the reader about the access to credit of small and medium sized enterprises (SMEs) in Vietnam based on two SME surveys. Recent evidence from a variety of sources suggests that credit to available to SMEs has increased over the past few years. This is confirmed by the two SME surveys. Fewer firms which applied for credit in 2005 were denied credit as compared to 2002. However, the rapid development of the private sector has also increased demand for credit (especially among the larger SMEs); and it appears that the formal financial sector is just managing to keep track with growth in general. We conclude by discussing these results and formulate a set of policy recommendations.Vietnam; credit constraints; financial markets
SME Fringe Benefits Provision
The aim of this paper is to inform the reader about the distribution of fringe benefits provided to employees by firms in 10 provinces of Vietnam. Five types of benefits are considered: Annual leave, maternity leave, sick leave, social insurance and health insurance. We especially focus on whether the gender of the owner has an effect on the fringe benefits provided. It appears that women firm owners are more likely to provide employees with fringes, and this gender effect exists primarily in non-household enterprises and is robust to the inclusion of standard determinants of wage compensation. We dscuss these results and formulate a set ofpolicy recommendations.Vietnam; gender; fringe benefits
The viscosity of silica fibres
The viscosity of an optical fibre over 1000 to 1150 {\deg}C is studied by
inscribing an optical fibre Bragg grating that can withstand temperatures up to
1200 {\deg}C and monitoring fibre elongation under load through the Bragg
wavelength shift. This optical interrogation offers high accuracy and
reliability compared to direct measurements of elongation, particularly at
lower temperatures, thus avoiding significant experimental error. An excellent
Arrhenius fit is obtained from which an activation energy for viscous flow of
Ea = 450 kJ/mol is extracted; addition of an additional temperature dependent
pre-exponential does not change this value. This value is less than that
idealised by some literature but consistent with other literature. The log plot
of viscosity is overall found to be consistent with that reported in the
literature for silica measurements on rod and beams, but substantially higher
to past work reported for optical fibres. The discrepancy from an idealised
activation energy Ea ~ 700 kJ/mol may be explained by noting the higher fictive
temperature of the fibre. On the other hand, past optical fibre results
obtained by beam bending with much lower values leave questions regarding the
method of viscosity measurement and the time taken for structural
equilibration. We note that because regenerated gratings already involve
post-annealing to stabilise their operation at higher temperature, the
structures are much more relaxed compared to normal fibres. This work
highlights the need to stabilize components for operation in harsh environments
before their application, despite some mechanical compromise. Given the
increasing expectation of all-optical waveguide technologies operating above
1000 {\deg}C, the need to study the behaviour of glass over the long term
brings added significance to the basic understanding of glass in this regime.Comment: Submitted to Acta Material
An Analysis of the Dynamics of the US Commercial Air Transportation System
Major trends in the airline industry are analyzed to highlight key dynamics that govern the US domestic air transportation system. The hypothesis is that air travel supply and demand equilibriums, a reliance on outside capital, and intra-industry competition are among the most critical forces that are driving the current restructuring of the airline industry. Data on airline operational and financial performance is used to trace these dynamics as the industry evolved through periods of industry deregulation, an economic growth bubble, and the aftermath of the attacks of September 11, 2001. The thesis identifies the post-deregulation development of hub-and-spoke networks and yield management systems as the key forces that would set the stage for a bifurcation of the air travel market during a cycle of economic growth in the late 1990’s. During this bubble economy, the dynamics of supply and demand fundamentally shifted as the major carriers focused on high-revenue, high-cost operations and travelers began to flock to newer low-fare, low-cost carriers. With the end of the economic growth cycle in 2000, the bifurcation of the airline industry began to affect revenues and profits at the major carriers. Massive and unprecedented industry losses would ensue, and would be compounded by the attacks of 9/11. Airline operational strategies in response to 9/11 and longer-term restructuring efforts are discussed in order to further identify the key dynamics affecting the air transportation system. These dynamics are synthesized and then discussed within the broader context of the air transportation system, the impact of air travel on the economy and mobility, and the role of government.MIT Global Airline Industry Program, Alfred P. Sloan Foundation
Line-Adaptive Hybrid Coding of Images
This Paper Describes Novel Adaptation Strategy for Hybrid Transform/DPCM Image Coders. This Strategy Has Yielded a 2–8 DB Increase in Signal-To-Noise Ratio in the Transmission of a Head and Shoulders Image at Bit Rates of 1–4 Bits Per Pel and One-Dimensional Transform Block Sizes of 2–16. © 1983 IEE
Influenza vaccines really work? Keeping apart the true from the false
A yearly seasonal flu vaccine is the best preventive method we have against influenza at this time. Even then, vaccination adoption is hampered by on-going discussions about safety and effectiveness. In order to dot the I's and cross the T's at the fifth ESWI influenza conference, a dedicated SPI track focused on these important aspects of influenza vaccination
Connecting the Dots: The Promise of Integrated Data Systems for Policy Analysis and Systems Reform
This article explores the use of integrated administrative data systems in support of policy reform through interagency collaboration and research. The legal, ethical, scientific and economic challenges of interagency data sharing are examined. A survey of eight integrated data systems, including states, local governments and university-based efforts, explores how the developers have addressed these challenges. Some exemplary uses of the systems are provided to illustrate the range, usefulness and import of these systems for policy and program reform. Recommendations are offered for the broader adoption of these systems and for their expanded use by various stakeholders
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