770 research outputs found
Survey on HIV risk perception and sexual behaviours among seafarers
Because the nature of their work seafarers spend long periods of time away from their families
and therefore represent a group at risk for sexually transmitted diseases, including HIV infection.
This paper reports the results of a survey to evaluate awareness and knowledge of the risk of HIV
infection among seafarers. Risky behaviours for HIV transmission were also assessed. The survey
was conducted using anonymous questionnaires on 197 workers of 9 vessels and 26 office
employees of an Italian shipping company (FINAVAL S.p.A., Rome). The respondents considered
HIV/AIDS as one of the diseases with a high risk of transmission. Most respondents had a good
general knowledge of HIV/AIDS and on the ways of its transmission. However, there is still lack of
knowledge on the basics of this disease. On the other hand, in spite of knowledge and awareness
about the risks of the disease, only 56.35% of the interviewed crewmembers used protection
in sexual intercourse with occasional partners. Compared to data available in literature, the
percentage of self-protecting people is increasing, but the number of seafarers exposing themselves
to risky behaviours is still high. As expected, condoms are used with regular partners with
lower frequency compared to occasional intercourse. The results of this survey indicate that
adequate prevention campaigns and major attention paid to seafarers health is useful for stimulating
responsible conduct for the prevention of infectious diseases, including HIV infection.
Nevertheless, it is still necessary to increase information about the risk of sexually transmitted
diseases and how to reduce it.
(Int Marit Health 2011; 62, 2: 131–137
Simulation, Experiment, and Evolution: Understanding Nucleation in Protein S6 Folding
In this study, we explore nucleation and the transition state ensemble of the
ribosomal protein S6 using a Monte Carlo Go model in conjunction with
restraints from experiment. The results are analyzed in the context of
extensive experimental and evolutionary data. The roles of individual residues
in the folding nucleus are identified and the order of events in the S6 folding
mechanism is explored in detail. Interpretation of our results agrees with, and
extends the utility of, experiments that shift f-values by modulating
denaturant concentration and presents strong evidence for the realism of the
mechanistic details in our Monte Carlo Go model and the structural
interpretation of experimental f-values. We also observe plasticity in the
contacts of the hydrophobic core that support the specific nucleus. For S6,
which binds to RNA and protein after folding, this plasticity may result from
the conformational flexibility required to achieve biological function. These
results present a theoretical and conceptual picture that is relevant in
understanding the mechanism of nucleation in protein folding.Comment: PNAS in pres
Decoupling between precipitation processes and mountain wave induced circulations observed with a vertically pointing K-Band Doppler radar
Recent studies reported that precipitation and mountain waves induced low tropospheric level circulations may be decoupled or masked by greater spatial scale variability despite generally there is a connection between microphysical processes of precipitation and mountain driven air flows. In this paper we analyse two periods of a winter storm in the Eastern Pyrenees mountain range (NE Spain) with different mountain wave induced circulations and low-level turbulence as revealed by Micro Rain Radar (MRR), microwave radiometer and Parsivel disdrometer data during the Cerdanya-2017 field campaign. We find that during the event studied mountain wave wind circulations and low-level turbulence do not affect neither the snow crystal riming or aggregation along the vertical column nor the surface particle size distribution of the snow. This study illustrates that precipitation profiles and mountain induced circulations may be decoupled which can be very relevant for either ground-based or spaceborne remote sensing of precipitation
NUGENIA/TA2 Achievements in Severe Accidents Research (2015-2020)
Severe accident research is the only way to achieve the best possible management in case such unlikely events eventually happen. Early this century, the Severe Accident Research NETwork (SARNET) was born as an EC project and about 10 years later it became the technical area 2 of NUGENIA, the SNETP (Sustainable Nuclear Energy Technological Platform) pillar devoted to research on Gen. II and Gen. III Light Water Reactors (LWRs). This paper describes the most relevant outcomes from NUGENIA/TA2 research in the last five years concerning coolability of in-vessel and ex-vessel corium/debris, in-containment phenomena and source term; besides, the progress made and underway on severe accident modelling is outlined. Finally, the NUGENIA/TA2 commitment to knowledge dissemination through courses and conferences is highlighted
Non-Exponential Kinetics of Loop Formation in Proteins and Peptides: A Signature of Rugged Free Energy Landscapes?
The kinetics of loop formation, i.e., the occurrence of contact between two atoms of a polypeptide, remains the focus of continuing interest. One of the reasons is that contact formation is the elementary event underlying processes such as folding and binding. More importantly, it is experimentally measurable and can be predicted theoretically for ideal polymers. Deviations from single exponential kinetics have sometimes been interpreted as a signature of rugged, protein-like, free energy landscapes. Here we present simulations, with different atomistic models, of short peptides with varied structural propensity, and of a structured protein. Results show exponential contact formation kinetics (or relaxation) at long times, and a power law relaxation at very short times. At intermediate times a deviation from either power law or simple exponential kinetics is observed that appears to be characteristic of polypeptides with either specific or non-specific attractive interactions, but disappears if attractive interactions are absent. Our results agree with recent experimental measurements on peptides and proteins and offer a comprehensive interpretation for them
Growth performances, chemical composition, and microbiological loads of mealworm reared with brewery spent grains and bread leftovers
Tenebrio molitor (mealworm) larvae are one of the most intriguing edible insects, and they may be raised on a variety of substrates, including by-products, side-stream products, and former foodstuff. The substrates could affect drastically the productive performances as well as the chemical-nutritional value of the larvae. In this study we tested two main substrate ingredients, brewery spent grains (SG) and bread leftovers (B), without adding any other dry ingredients. In order to correlate the chemical composition of the substrates to the larvae characteristics, five different diets were tested as 100% of a single ingredient (SG100 and B100), 75–25% mixes (SG75B25 and SG25B75) and 50–50% mixes (SG50B50). The effects of the substrate were tested on the development rates, chemical composition, and microbial loads of mealworm larvae. The effects of fasting, washing, and cooking were also tested on the microbiological determinations. Results indicate that all the parameters were affected by the chemical compositions of the substrates. The larvae fed the higher contents of SG showed the best growth performances along with higher nutritional values. The diet with only bread (B100) showed the worst parameters, both on the growth performances and on the nutritive values. Microbial loads were also affected by the diets, with minor effects in relation to the washing and fasting procedures, while cooking drastically reduced all the microbial loads. Taking into account that the two employed ingredients were former foodstuff or by-products it is important to highlight the capacity of mealworms to positively convert side-stream materials into rich nutritional animal products.Highlights Mealworm could be proficiently reared on brewery spent grains and bread leftovers converting them into nutritional animal products. Mealworm productive performances and nutritional value could be affected by the employed substrate. Evidence of high mealworms plasticity and potential tailor made of the final outcomes
Status and perspectives of SARNET network
43 organisations (research, universities, industry, utilities, safety authorities and TSO) from 22 countries network their capabilities for R&D on
Severe Accidents (SA) in SARNET (Severe Accident Research NETwork of excellence) in the EC FP7 for 4 years from April 2009. The overall work
represents about 40 persons per year (230 researchers and 20 PhD students). A 43rd partner is currently joining the network: BARC (India).
See www.sar-net.e
Proposed relation between SARNET network on severe accidents and TWG Gen.II/III
SA Research Priorities defined in SARNET network should be the basis for proposing in the future relevant R&D programs to address them, when needed, and launch
projects with the endorsement of TWG
Vertical structure and microphysical observations of winter precipitation in an inner valley during the Cerdanya-2017 field campaign
Precipitation processes at windward and leeward sides of the mountains have been object of study for many decades. Instead, inner mountain valleys, where usually most mountain population lives, have received considerably less attention. This article examines precipitation processes during a winter field campaign in an inner valley of the Pyrenees (NE Spain) using, among other instruments, a K-band vertically pointing Doppler radar (Micro Rain Radar) and a laser-based optical disdrometer (Parsivel). A decoupling is found between the stalled air of the valley and the air of the free atmosphere above the mountain crest level, evidenced by an increase of turbulence and spectral width of precipitation particles. Wind shear layer may promote riming and aggregation of the ice and snow particles. Two main rainfall regimes are found during the campaign: (1) stratiform rainfall mostly produced by water vapour deposition processes, although sometimes riming and aggregation become important, and (2) weak convection with slight dominance of collision-coalescence processes. Precipitation characteristics at the bottom of the valley show typical continental features such as low Liquid Water Content, despite the valley is only about 100 km from the sea. This study demonstrates that inner valley may present distinct precipitation features with respect to windward and leeward precipitation
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