1,502 research outputs found
Gandlieri taâ l-Isqof
Ä abra taâ poeĆŒiji u proĆŒa li tinkludi: Ć»ewÄĄ Qronfliet taâ Dun Karm â Ä ustizzja Bla Qorti taâ Ä uĆŒĂš Galea â It-Tigra u l-ÄŠamiema taâ A. Buttigieg â Ä ewwa l-Presepju taâ R. M. B. â Salvu Jsir Missier taâ Vic. Apap â Madlien taâ K. G. M. F. â Imbierek il-Mulej! taâ Pran. Camilleri â Il-Gandlieri taâ l-Isqof taâ V. Hugo u maqlub għall-Malti minn G. Z. A.N/
Segregation of Mn, Si, Al, and oxygen during the friction stir welding of DH36 steel
This work investigates the role of welding speed
in elemental segregation of Mn, Si, Al, and oxygen during
friction stir welding (FSW) in DH36 steel. The experimental
work undertaken showed that when the speed of the
FSW process exceeds 500 RPM with a traverse speed of
400 mm/min, then elemental segregation of Mn, Si, Al,
and O occurred. The mechanism of this segregation is not
fully understood; additionally, the presence of oxygen
within these segregated elements needs investigation. This
work examines the elemental segregation within DH36
steel by conducting heat treatment experiments on unwelded
samples incrementally in the range of 1200â1500 °C
and at cooling rates similar to that in FSW process. The
results of heat treatments were compared with samples
welded under two extremes of weld tool speeds, namely
W1 low tool speeds (200 RPM with traverse speed of
100 mm/min) and W2 high tool speeds (550 RPM with
traverse speed of 400 mm/min). The results from the heat
treatment trials showed that segregation commences when
the temperature exceeds 1400 °C and Mn, Si, Al, and
oxygen segregation progress occurs at 1450 °C and at a
cooling rate associated with acicular ferrite formation. It
was also found that high rotational speeds exceeding
500 RPM caused localized melting at the advancing-trailing
side of the friction stir-welded samples. The study aims
to estimate peak temperature limits at which elemental
segregation does not occur and hence prevent their occurrence
in practice by applying the findings to the toolâs
rotational and traverse speed that correspond to the defined
temperature
Role of biological markers for cerebral bleeding risk STRATification in patients with atrial fibrillation on oral anticoagulants for primary or secondary prevention of ischemic stroke (Strat-AF study): Study design and methodology
Association Between Motor and Cognitive Performances in Elderly With Atrial Fibrillation: Strat-AF Study
Common Genetic Variation in GLP1R and Insulin Secretion in Response to Exogenous GLP-1 in Nondiabetic Subjects: A pilot study
OBJECTIVE:
Glucagon-like peptide (GLP)-1 receptor is encoded by GLP1R. The effect of genetic variation at this locus on the response to GLP-1 is unknown. This study assessed the effect of GLP1R polymorphisms on insulin secretion in response to hyperglycemia and to infused GLP-1 in nondiabetic subjects.
RESEARCH DESIGN AND METHODS:
Eighty-eight healthy individuals (aged 26.3 +/- 0.6 years, fasting glucose 4.83 +/- 0.04 mmol/l) were studied using a hyperglycemic clamp. GLP-1 was infused for the last 2 h of the study (0.75 pmol/kg/min over 121-180 min, 1.5 pmol/kg/min over 181-240 min). beta-Cell responsivity (Phi(Total)) was measured using a C-peptide minimal model. The effect of 21 tag single nucleotide polymorphisms (SNPs) in GLP1R on Phi(Total) was examined.
RESULTS:
Two SNPs (rs6923761 and rs3765467) were nominally associated with altered beta-cell responsivity in response to GLP-1 infusion.
CONCLUSIONS:
Variation in GLP1R may alter insulin secretion in response to exogenous GLP-1. Future studies will determine whether such variation accounts for interindividual differences in response to GLP-1-based therapy
Comparing nuclear power trajectories in Germany and the UK: from âregimes' to âdemocraciesâ in sociotechnical transitions and Discontinuities
This paper focuses on arguably the single most striking contrast in contemporary major energy politics in Europe (and even the developed world as a whole): the starkly differing civil nuclear policies of Germany and the UK. Germany is seeking entirely to phase out nuclear power by 2022. Yet the UK advocates a ânuclear renaissanceâ, promoting the most ambitious new nuclear construction programme in Western Europe.Here,this paper poses a simple yet quite fundamental question: what are the particular divergent conditions most strongly implicated in the contrasting developments in these two countries. With nuclear playing such an iconic role in historical discussions over technological continuity and transformation, answering this may assist in wider understandings of sociotechnical incumbency and discontinuity in the burgeoning field ofâsustainability transitionsâ. To this end, an âabductiveâ approach is taken: deploying nine potentially relevant criteria for understanding the different directions pursued in Germany and the UK. Together constituted by 30 parameters spanning literatures related to socio-technical regimes in general as well as nuclear technology in particular, the criteria are divided into those that are âinternalâ and âexternalâ to the âfocal regime configurationâ of nuclear power and associated âchallenger technologiesâ like renewables.
It is âinternalâ criteria that are emphasised in conventional sociotechnical regime theory, with âexternalâ criteria relatively less well explored. Asking under each criterion whether attempted discontinuation of nuclear power would be more likely in Germany or the UK, a clear picture emerges. âInternalâ criteria suggest attempted nuclear discontinuation should be more likely in the UK than in Germanyâ the reverse of what is occurring.
âExternalâ criteria are more aligned with observed dynamics âespecially those relating to military nuclear commitments and broader âqualities of democracyâ. Despite many differences of framing concerning exactly what constitutes âdemocracyâ, a rich political science literature on this point is unanimous in characterising Germany more positively than the UK. Although based only on a single case,a potentially important question is nonetheless raised as to whether sociotechnical regime theory might usefully give greater attention to the general importance of various aspects of democracy in constituting conditions for significant technological discontinuities and transformations. If so, the policy implications are significant. A number of important areas are identified for future research, including the roles of diverse understandings and specific aspects of democracy and the particular relevance of military nuclear commitmentsâ whose under-discussion in civil nuclear policy literatures raises its own questions of democratic accountability
Production properties of K*(892) vector mesons and their spin alignment as measured in the NOMAD experiment
First measurements of K*(892) mesons production properties and their spin
alignment in nu_mu charged current (CC) and neutral current (NC) interactions
are presented. The analysis of the full data sample of the NOMAD experiment is
performed in different kinematic regions. For K*+ and K*- mesons produced in
nu_mu CC interactions and decaying into K0 pi+/- we have found the following
yields per event: (2.6 +/- 0.2 (stat.) +/- 0.2 (syst.))% and (1.6 +/- 0.1
(stat.) +/- 0.1 (syst.))% respectively, while for the K*+ and K*- mesons
produced in nu NC interactions the corresponding yields per event are: (2.5 +/-
0.3 (stat.) +/- 0.3 (syst.))% and (1.0 +/- 0.3 (stat.) +/- 0.2 (syst.))%. The
results obtained for the rho00 parameter, 0.40 +/- 0.06 (stat) +/- 0.03 (syst)
and 0.28 +/- 0.07 (stat) +/- 0.03 (syst) for K*+ and K*- produced in nu_mu CC
interactions, are compared to theoretical predictions tuned on LEP measurements
in e+e- annihilation at the Z0 pole. For K*+ mesons produced in nu NC
interactions the measured rho00 parameter is 0.66 +/- 0.10 (stat) +/- 0.05
(syst).Comment: 20 p
Prediction of Neutrino Fluxes in the NOMAD Experiment
The method developed for the calculation of the flux and composition of the
West Area Neutrino Beam used by NOMAD in its search for neutrino oscillations
is described. The calculation is based on particle production rates computed
using a recent version of FLUKA and modified to take into account the cross
sections measured by the SPY and NA20 experiments. These particles are
propagated through the beam line taking into account the material and magnetic
fields they traverse. The neutrinos produced through their decays are tracked
to the NOMAD detector. The fluxes of the four neutrino flavours at NOMAD are
predicted with an uncertainty of about 8% for nu(mu) and nu(e), 10% for
antinu(mu), and 12% for antinu(e). The energy-dependent uncertainty achieved on
the R(e, mu) prediction needed for a nu(mu)->nu(e) oscillation search ranges
from 4% to 7%, whereas the overall normalization uncertainty on this ratio is
4.2%.Comment: 43 pages, 20 figures. Submitted to Nucl. Phys.
Final NOMAD results on nu_mu->nu_tau and nu_e->nu_tau oscillations including a new search for nu_tau appearance using hadronic tau decays
Results from the nu_tau appearance search in a neutrino beam using the full
NOMAD data sample are reported. A new analysis unifies all the hadronic tau
decays, significantly improving the overall sensitivity of the experiment to
oscillations. The "blind analysis" of all topologies yields no evidence for an
oscillation signal. In the two-family oscillation scenario, this sets a 90%
C.L. allowed region in the sin^2(2theta)-Delta m^2 plane which includes
sin^2(2theta)<3.3 x 10^{-4} at large Delta m^2 and Delta m^2 < 0.7 eV^2/c^4 at
sin^2(2theta)=1. The corresponding contour in the nu_e->nu_tau oscillation
hypothesis results in sin^2(2theta)<1.5 x 10^{-2} at large Delta m^2 and Delta
m^2 < 5.9 eV^2/c^4 at sin^2(2theta)=1. We also derive limits on effective
couplings of the tau lepton to nu_mu or nu_e.Comment: 46 pages, 16 figures, Latex, to appear on Nucl. Phys.
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