540 research outputs found
The Influence of Spatial Resolution due to Hot-Wire Sensors on Measurements in Wall-Bounded Turbulence.
Reassessment of compiled data reveal that recorded scatter in the hot-wire measured near-wall peak in viscous-scaled streamwise turbulence intensity is due in large part to the simultaneous competing effects of Reynolds number and viscous-scaled wire-length l ( lUt n, where l is the wirelength, Ut is friction velocity and n is kinematic viscosity). These competing factors can explain much of the disparity in existing literature, in particular explaining how previous studies have incorrectly concluded that the inner-scaled near-wall peak is independent of Re. We also investigate the appearance of the, so-called, ‘outerpeak’ in the broadband streamwise intensity, found by some researchers to occur within the log-region of high Reynolds number boundary layers. We show that this ‘outer-peak’ is most likely a symptom of attenuation of small-scales due to large l . Fully mapped energy spectra, obtained with two different l , are presented to demonstrate this phenomena. The spatial attenuation resulting from wires with large l effectively filters small-scale fluctuations from the recorded signal
Vapor Distribution above an Evaporating Sessile Drop
An experimental technique was developed that uses infrared tomography to measure the three-dimensional vapor distribution above an evaporating sessile drop. The technique was applied to measure the vapor distributions above evaporating drops of hexane and 3-methylpentane (3MP) at room temperature and pressure. The molecular masses of these two species are heavier than air and the vapor from the evaporating drop forms a flat, disk-shaped cloud. A Fourier transform infrared spectrometer (FTIR) was used to measure the spectral absorbance along a set of paths passing through the vapor cloud. From a set of path-averaged absorbance measurements, a two-dimensional spatial concentration distribution was determined using a computed tomography routine. A three-dimensional concentration distribution was obtained from multiple two-dimensional distributions obtained at different elevations above the drop. The vapor distributions for both hexane and 3MP differ significantly from the values predicted by the solutions for diffusion-limited evaporation and indicate the effect of buoyancy-induced convection of the vapor. These measurements are the first quantitative measurements of the vapor distribution above a sessile drop and are important for advancing the understanding of the vapor phase transport mechanisms, and thus sessile drop evaporation
Restructuring Cross Border Groups: Key Considerations Around Foreign Tax and Finance Driven SPVs
Coherent privaatrech
Non-coding nucleotides and amino acids near the active site regulate peptide deformylase expression and inhibitor susceptibility in Chlamydia trachomatis
Chlamydia trachomatis, an obligate intracellular bacterium, is a highly prevalent human pathogen. Hydroxamic-acid-based matrix metalloprotease inhibitors can effectively inhibit the pathogen both in vitro and in vivo, and have exhibited therapeutic potential. Here, we provide genome sequencing data indicating that peptide deformylase (PDF) is the sole target of the inhibitors in this organism. We further report molecular mechanisms that control chlamydial PDF (cPDF) expression and inhibition efficiency. In particular, we identify the σ66-dependent promoter that controls cPDF gene expression and demonstrate that point mutations in this promoter lead to resistance by increasing cPDF transcription. Furthermore, we show that substitution of two amino acids near the active site of the enzyme alters enzyme kinetics and protein stability
Recommended from our members
Social cohesion and the notion of 'suspect communities': A study of the experiences and impacts of being 'suspect' for Irish communities and Muslim communities in Britain
In this article, we consider how the practice of conceiving of groups within civil society as 'communities' meshes with conceptualisations of certain populations as 'suspect' and consider some of the impacts and consequences of this for particular populations and for social cohesion. We examine how Irish and Muslim people in Britain have become aware of and have experienced themselves to be members of 'suspect communities' in relation to political violence and counterterrorism policies from 1974 to 2007 and investigate the impacts of these experiences on their everyday lives. The study focuses on two eras of political violence. The first coincides with the Irish Republican Army's (IRA) bombing campaigns in England between 1973 and 1996, when the perpetrators were perceived as 'Irish terrorists'; and the second since 2001, when, in Britain and elsewhere, the main threat of political violence has been portrayed as stemming from people who are assumed to be motivated by extreme interpretations of Islam and are often labelled as 'Islamic terrorists'. We outline why the concept of 'suspect communities' continues to be analytically useful for examining: the impact of 'bounded communities' on community cohesion policies; the development of traumatogenic environments and their ramifications; and for examining how lessons might be learnt from one era of political violence to another, especially as regards the negative impacts of practices of suspectification on Irish communities and Muslim communities. The research methods included discussion groups involving Irish and Muslim people. These demonstrated that with the removal of discourses of suspicion the common ground of Britain's urban multiculture was a sufficient basis for sympathetic exchanges. © 2012 Taylor and Francis Group, LLC
Priming Picture Naming with a Semantic Task: An fMRI Investigation
Prior semantic processing can enhance subsequent picture naming performance, yet the neurocognitive mechanisms underlying this effect and its longevity are unknown. This functional magnetic resonance imaging study examined whether different neurological mechanisms underlie short-term (within minutes) and long-term (within days) facilitation effects from a semantic task in healthy older adults. Both short- and long-term facilitated items were named significantly faster than unfacilitated items, with short-term items significantly faster than long-term items. Region of interest results identified decreased activity for long-term facilitated items compared to unfacilitated and short-term facilitated items in the mid-portion of the middle temporal gyrus, indicating lexical-semantic priming. Additionally, in the whole brain results, increased activity for short-term facilitated items was identified in regions previously linked to episodic memory and object recognition, including the right lingual gyrus (extending to the precuneus region) and the left inferior occipital gyrus (extending to the left fusiform region). These findings suggest that distinct neurocognitive mechanisms underlie short- and long-term facilitation of picture naming by a semantic task, with long-term effects driven by lexical-semantic priming and short-term effects by episodic memory and visual object recognition mechanisms
Clinical map document based on XML (cMDX): document architecture with mapping feature for reporting and analysing prostate cancer in radical prostatectomy specimens
<p>Abstract</p> <p>Background</p> <p>The pathology report of radical prostatectomy specimens plays an important role in clinical decisions and the prognostic evaluation in Prostate Cancer (PCa). The anatomical schema is a helpful tool to document PCa extension for clinical and research purposes. To achieve electronic documentation and analysis, an appropriate documentation model for anatomical schemas is needed. For this purpose we developed cMDX.</p> <p>Methods</p> <p>The document architecture of cMDX was designed according to Open Packaging Conventions by separating the whole data into template data and patient data. Analogue custom XML elements were considered to harmonize the graphical representation (e.g. tumour extension) with the textual data (e.g. histological patterns). The graphical documentation was based on the four-layer visualization model that forms the interaction between different custom XML elements. Sensible personal data were encrypted with a 256-bit cryptographic algorithm to avoid misuse. In order to assess the clinical value, we retrospectively analysed the tumour extension in 255 patients after radical prostatectomy.</p> <p>Results</p> <p>The pathology report with cMDX can represent pathological findings of the prostate in schematic styles. Such reports can be integrated into the hospital information system. "cMDX" documents can be converted into different data formats like text, graphics and PDF. Supplementary tools like cMDX Editor and an analyser tool were implemented. The graphical analysis of 255 prostatectomy specimens showed that PCa were mostly localized in the peripheral zone (Mean: 73% ± 25). 54% of PCa showed a multifocal growth pattern.</p> <p>Conclusions</p> <p>cMDX can be used for routine histopathological reporting of radical prostatectomy specimens and provide data for scientific analysis.</p
BALL - biochemical algorithms library 1.3
<p>Abstract</p> <p>Background</p> <p>The Biochemical Algorithms Library (BALL) is a comprehensive rapid application development framework for structural bioinformatics. It provides an extensive C++ class library of data structures and algorithms for molecular modeling and structural bioinformatics. Using BALL as a programming toolbox does not only allow to greatly reduce application development times but also helps in ensuring stability and correctness by avoiding the error-prone reimplementation of complex algorithms and replacing them with calls into the library that has been well-tested by a large number of developers. In the ten years since its original publication, BALL has seen a substantial increase in functionality and numerous other improvements.</p> <p>Results</p> <p>Here, we discuss BALL's current functionality and highlight the key additions and improvements: support for additional file formats, molecular edit-functionality, new molecular mechanics force fields, novel energy minimization techniques, docking algorithms, and support for cheminformatics.</p> <p>Conclusions</p> <p>BALL is available for all major operating systems, including Linux, Windows, and MacOS X. It is available free of charge under the Lesser GNU Public License (LPGL). Parts of the code are distributed under the GNU Public License (GPL). BALL is available as source code and binary packages from the project web site at <url>http://www.ball-project.org</url>. Recently, it has been accepted into the debian project; integration into further distributions is currently pursued.</p
- …