Helicopter Pilot Performance for Discrete-maneuver Flight Tasks

This paper describes a current study of several basic helicopter flight maneuvers. The data base consists of in-flight measurements from instrumented helicopters using experienced pilots. The analysis technique is simple enough to apply without automatic data processing, and the results can be used to build quantitative matah models of the flight task and some aspects of the pilot control strategy. In addition to describing the performance measurement technqiue, some results are presented which define the aggressiveness and amplitude of maneuvering for several lateral maneuvers including turns and sidesteps

T-PHOT version 2.0: improved algorithms for background subtraction, local convolution, kernel registration, and new options

We present the new release v2.0 of T-PHOT, a publicly available software package developed to perform PSF-matched, prior-based, multiwavelength deconfusion photometry of extragalactic fields. New features included in the code are presented and discussed: background estimation, fitting using position dependent kernels, flux prioring, diagnostical statistics on the residual image, exclusion of selected sources from the model and residual images, individual registration of fitted objects. These new options improve on the performance of the code, allowing for more accurate results and providing useful aids for diagnostics.Comment: 7 pages, 8 figure

Study of helicopterroll control effectiveness criteria

A study of helicopter roll control effectiveness based on closed-loop task performance measurement and modeling is presented. Roll control critieria are based on task margin, the excess of vehicle task performance capability over the pilot's task performance demand. Appropriate helicopter roll axis dynamic models are defined for use with analytic models for task performance. Both near-earth and up-and-away large-amplitude maneuvering phases are considered. The results of in-flight and moving-base simulation measurements are presented to support the roll control effectiveness criteria offered. This Volume contains the theoretical analysis, simulation results and criteria development

Control of Membrane Fusion Mechanism by Lipid Composition: Predictions from Ensemble Molecular Dynamics

Membrane fusion is critical to biological processes such as viral infection, endocrine hormone secretion, and neurotransmission, yet the precise mechanistic details of the fusion process remain unknown. Current experimental and computational model systems approximate the complex physiological membrane environment for fusion using one or a few protein and lipid species. Here, we report results of a computational model system for fusion in which the ratio of lipid components was systematically varied, using thousands of simulations of up to a microsecond in length to predict the effects of lipid composition on both fusion kinetics and mechanism. In our simulations, increased phosphatidylcholine content in vesicles causes increased activation energies for formation of the initial stalk-like intermediate for fusion and of hemifusion intermediates, in accordance with previous continuum-mechanics theoretical treatments. We also use our large simulation dataset to quantitatively compare the mechanism by which vesicles fuse at different lipid compositions, showing a significant difference in fusion kinetics and mechanism at different compositions simulated. As physiological membranes have different compositions in the inner and outer leaflets, we examine the effect of such asymmetry, as well as the effect of membrane curvature on fusion. These predicted effects of lipid composition on fusion mechanism both underscore the way in which experimental model system construction may affect the observed mechanism of fusion and illustrate a potential mechanism for cellular regulation of the fusion process by altering membrane composition

H-ATLAS/GAMA and HeViCS – dusty early-type galaxies in different environments

The Herschel Space Observatory has had a tremendous impact on the study of extragalactic dust. Specifically, early-type galaxies (ETG) have been the focus of several studies. In this paper, we combine results from two Herschel studies – a Virgo cluster study Herschel Virgo Cluster Survey (HeViCS) and a broader, low-redshift Herschel-Astrophysical Terahertz Large Area Survey (H-ATLAS)/Galaxy and Mass Assembly (GAMA) study – and contrast the dust and associated properties for similar mass galaxies. This comparison is motivated by differences in results exhibited between multiple Herschel studies of ETG. A comparison between consistent modified blackbody derived dust mass is carried out, revealing strong differences between the two samples in both dust mass and dust-to-stellar mass ratio. In particular, the HeViCS sample lacks massive ETG with as high a specific dust content as found in H-ATLAS. This is most likely connected with the difference in environment for the two samples. We calculate nearest neighbour environment densities in a consistent way, showing that H-ATLAS ETG occupy sparser regions of the local Universe, whereas HeViCS ETG occupy dense regions. This is also true for ETG that are not Herschel-detected but are in the Virgo and GAMA parent samples. Spectral energy distributions are fit to the panchromatic data. From these, we find that in H-ATLAS the specific star formation rate anticorrelates with stellar mass and reaches values as high as in our Galaxy. On the other hand HeViCS ETG appear to have little star formation. Based on the trends found here, H-ATLAS ETG are thought to have more extended star formation histories and a younger stellar population than HeViCS ETG

Ten Simple Rules for Getting Help from Online Scientific Communities

The increasing complexity of research requires scientists to work at the intersection of multiple fields and to face problems for which their formal education has not prepared them. For example, biologists with no or little background in programming are now often using complex scripts to handle the results from their experiments; vice versa, programmers wishing to enter the world of bioinformatics must know about biochemistry, genetics, and other fields. In this context, communication tools such as mailing lists, web forums, and online communities acquire increasing importance. These tools permit scientists to quickly contact people skilled in a specialized field. A question posed properly to the right online scientific community can help in solving difficult problems, often faster than screening literature or writing to publication authors. The growth of active online scientific communities, such as those listed in Table S1, demonstrates how these tools are becoming an important source of support for an increasing number of researchers. Nevertheless, making proper use of these resources is not easy. Adhering to the social norms of World Wide Web communication—loosely termed “netiquette”—is both important and non-trivial. In this article, we take inspiration from our experience on Internet-shared scientific knowledge, and from similar documents such as “Asking the Questions the Smart Way” and “Getting Answers”, to provide guidelines and suggestions on how to use online communities to solve scientific problems

Single-Crystal-to-Single-Crystal Transformation of a Novel 2-Fold Interpenetrated Cadmium-Organic Framework with Trimesate and 1,2-Bis(4-pyridyl)ethane into the Thermally Desolvated Form Which Exhibits Liquid and Gas Sorption Properties

A novel 2-fold interpenetrated pillared cadmium metal organic framework namely [Cd(HBTC)-BPE](n)center dot nDMF has been synthesized using 1,3,5-benzenetricarboxylic acid and 1,2-bis(4-pyridyl)ethane (BPE). This compound has been desolvated and subjected to various liquids and gases for sorption studies. Structures of the assynthesized (1) desolvated (2) and resolvated in benzene (3) have been determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis IR spectra, and thermogravimetric/differential scanning calorimetry analysis. Single crystal X-ray analysis revealed a 2-fold interpenetrated, three-dimensional (3D) framework which exhibits a 3,5-connected network with the Schlafli symbol of [(6(3))(6(9).8) and hms topology. Compound I exhibits a temperature-induced single-crystal-to-single-crystal (SC SC) transformation upon the release of N,N'-dimethylformamide molecules forming compound 2 (stable up to 300 C). SC SC transformation is also observed when it is immersed in benzene, chloroform, 1,4dioxane, and tetrahydrofuran. The uptake of different solvent molecules was analyzed, and desolvated samples selectively adsorb benzene, chloroform, 1,4-dioxane, and THF molecules over other selected polar solvents. Gas (N-2, CO2, and N2O) sorption experiments were also performed and the structure showed 2.5% N-2 4.5% CO2, and 3.4% N2O absorption by mass at room temperature and moderate gas pressures (similar to 10 bar)

Keeping Confidence: Responsibility and public health

Keeping Confidence: HIV and the criminal law from service provider perspectives Duration: June 2012 - March 2013 The Monument Trust generously funded Sigma Research at London School of Hygiene and Tropical Medicine and Birkbeck College to undertake a qualitative study on perceptions of criminal prosecutions for HIV transmission among HIV service providers. Five short reports outlining the key findings of the study focus on the main themes arising from our analysis of the focus group discussions. The findings and associated policy and practice recommendations will be of interest to: those who provide HIV health and social care and their professional bodies (for instance NHIVNA, CHIVA, BHIVA, BASHH, SSHA, BPS), police and others who play a role in criminal investigations and trials, and people with diagnosed HIV

Keeping Confidence: Understanding the Law

Keeping Confidence: HIV and the criminal law from service provider perspectives Duration: June 2012 - March 2013 The Monument Trust generously funded Sigma Research at London School of Hygiene and Tropical Medicine and Birkbeck College to undertake a qualitative study on perceptions of criminal prosecutions for HIV transmission among HIV service providers. Five short reports outlining the key findings of the study focus on the main themes arising from our analysis of the focus group discussions. The findings and associated policy and practice recommendations will be of interest to: those who provide HIV health and social care and their professional bodies (for instance NHIVNA, CHIVA, BHIVA, BASHH, SSHA, BPS), police and others who play a role in criminal investigations and trials, and people with diagnosed HIV