902 research outputs found
A plasticity model for powder compaction processes incorporating particle deformation and rearrangement
This article is available open access through the publisher’s website at the link below. Copyright @ 2008 Elsevier Ltd.This paper develops a mechanistic model of granular materials that can be used with a commercial finite element package (ABAQUS). The model draws on the ideas of critical state soil mechanics and combines them with the theory of envelopes to develop an elasto-plastic model with a non-associated flow rule. The model incorporates both local deformation at the granule contacts, and rearrangement of the granules so that jointly they account for any bulk deformation. The mechanics of the model closely reflect the physicality of the material behaviour and the model parameters are closely linked (although not simplistically identical) to the characteristics of the granules. This not only gives an insight into the material behaviour, but also enables the model to be used to facilitate design of the material, its processing properties and, hence, component development. The model is used to simulate drained triaxial tests, settlement of a powder in a bin, and some examples of die pressing. Simulations are compared with experimental data and with predictions obtained using other models
The local power of the gradient test
The asymptotic expansion of the distribution of the gradient test statistic
is derived for a composite hypothesis under a sequence of Pitman alternative
hypotheses converging to the null hypothesis at rate , being the
sample size. Comparisons of the local powers of the gradient, likelihood ratio,
Wald and score tests reveal no uniform superiority property. The power
performance of all four criteria in one-parameter exponential family is
examined.Comment: To appear in the Annals of the Institute of Statistical Mathematics,
this http://www.ism.ac.jp/editsec/aism-e.htm
Electromagnetically induced transparency in multi-level cascade scheme of cold rubidium atoms
We report an experimental investigation of electromagnetically induced
transparency in a multi-level cascade system of cold atoms. The absorption
spectral profiles of the probe light in the multi-level cascade system were
observed in cold Rb-85 atoms confined in a magneto-optical trap, and the
dependence of the spectral profile on the intensity of the coupling laser was
investigated. The experimental measurements agree with the theoretical
calculations based on the density matrix equations of the rubidium cascade
system.Comment: 9 pages, 5 figure
Comparing the efficacy, safety, and utility of intensive insulin algorithms for a primary care practice
Diabetes management is firmly based within the primary care community. Landmark randomized, controlled trials have demonstrated that even modest reductions in glycated hemoglobin (HbA1c) can yield improvements in economic and medical end-points. Diabetes is a chronic, progressive disease associated with loss of pancreatic β-cell function. Therefore, most patients will eventually require insulin therapies in order to achieve their individualized targeted HbA1c as their β-cell function and mass wanes. Although clinicians understand the importance of early insulin initiation, there is little agreement as to when to introduce insulin as a therapeutic option. Once initiated, questions remain as to whether to allow the patients to self-titrate their dose or whether the dosing should be tightly regulated by the clinician. Physicians have many evidence-based basal insulin protocols from which to choose, all of which have been shown to drive HbA1c levels to the American Diabetes Association target of ≤7%. This article will discuss ways by which insulin therapies can be effectively introduced to patients within busy primary care practices. Published evidence-based basal insulin protocols will be evaluated for safety and efficacy
Investigating the association between baseline characteristics (HbA1c and Body Mass Index) and clinical outcomes of fast-acting insulin aspart in people with diabetes: a post hoc analysis
Introduction: The aim of this study was to investigate the association between baseline characteristics [HbA1c and body mass index (BMI)] and the effect of mealtime fast-acting insulin aspart (faster aspart) relative to insulin aspart (IAsp) or basal-only insulin therapy on several efficacy and safety outcomes in people with diabetes.
Methods: Post hoc analysis of three randomised phase 3a trials in people with type 1 diabetes (T1D; onset 1) and type 2 diabetes (T2D; onset 2 and 3). Participants (N = 1686) were stratified according to baseline BMI ( 58– 7.5–< 8.0%, ≥ 8.0%).
Results: In participants with T2D, the estimated treatment difference for change in HbA1c was similar for all BMI and HbA1c subgroups. No major differences between treatments were observed in risk of overall hypoglycaemia or insulin dose across subgroups. In participants with T1D, change in HbA1c was similar across BMI and HbA1c subgroups, and no major differences between treatments were observed for severe or blood glucose-confirmed hypoglycaemia across subgroups. Total daily insulin dose (U/kg) was similar across all baseline HbA1c groups and the BMI 30 kg/m 2 subgroup.
Conclusions: In participants with T1D and T2D, treatment differences (for change in HbA1c and overall hypoglycaemia) between mealtime faster aspart and insulin comparators were similar to the corresponding overall analysis across baseline HbA1c and BMI subgroups. The finding of a lower total daily insulin dose in participants with obesity (BMI > 30 kg/m 2 ) and T1D treated with faster aspart, versus those treated with IAsp, may warrant further investigation.
Trial Registration: ClinicalTrials.gov NCT01831765 (onset 1); NCT01819129 (onset 2); NCT01850615 (onset 3).
Funding: Novo Nordisk A/S, Søborg, Denmark
Single Spin Asymmetry in Polarized Proton-Proton Elastic Scattering at GeV
We report a high precision measurement of the transverse single spin
asymmetry at the center of mass energy GeV in elastic
proton-proton scattering by the STAR experiment at RHIC. The was measured
in the four-momentum transfer squared range \GeVcSq, the region of a significant interference between the
electromagnetic and hadronic scattering amplitudes. The measured values of
and its -dependence are consistent with a vanishing hadronic spin-flip
amplitude, thus providing strong constraints on the ratio of the single
spin-flip to the non-flip amplitudes. Since the hadronic amplitude is dominated
by the Pomeron amplitude at this , we conclude that this measurement
addresses the question about the presence of a hadronic spin flip due to the
Pomeron exchange in polarized proton-proton elastic scattering.Comment: 12 pages, 6 figure
High non-photonic electron production in + collisions at = 200 GeV
We present the measurement of non-photonic electron production at high
transverse momentum ( 2.5 GeV/) in + collisions at
= 200 GeV using data recorded during 2005 and 2008 by the STAR
experiment at the Relativistic Heavy Ion Collider (RHIC). The measured
cross-sections from the two runs are consistent with each other despite a large
difference in photonic background levels due to different detector
configurations. We compare the measured non-photonic electron cross-sections
with previously published RHIC data and pQCD calculations. Using the relative
contributions of B and D mesons to non-photonic electrons, we determine the
integrated cross sections of electrons () at 3 GeV/10 GeV/ from bottom and charm meson decays to be = 4.0({\rm
stat.})({\rm syst.}) nb and =
6.2({\rm stat.})({\rm syst.}) nb, respectively.Comment: 17 pages, 17 figure
Evolution of the differential transverse momentum correlation function with centrality in Au+Au collisions at GeV
We present first measurements of the evolution of the differential transverse
momentum correlation function, {\it C}, with collision centrality in Au+Au
interactions at GeV. {\it C} exhibits a strong dependence
on collision centrality that is qualitatively similar to that of number
correlations previously reported. We use the observed longitudinal broadening
of the near-side peak of {\it C} with increasing centrality to estimate the
ratio of the shear viscosity to entropy density, , of the matter formed
in central Au+Au interactions. We obtain an upper limit estimate of
that suggests that the produced medium has a small viscosity per unit entropy.Comment: 7 pages, 4 figures, STAR paper published in Phys. Lett.
Antibacterial Resistance Leadership Group 2.0: Back to Business
In December 2019, the Antibacterial Resistance Leadership Group (ARLG) was awarded funding for another 7-year cycle to support a clinical research network on antibacterial resistance. ARLG 2.0 has 3 overarching research priorities: infections caused by antibiotic-resistant (AR) gram-negative bacteria, infections caused by AR gram-positive bacteria, and diagnostic tests to optimize use of antibiotics. To support the next generation of AR researchers, the ARLG offers 3 mentoring opportunities: the ARLG Fellowship, Early Stage Investigator seed grants, and the Trialists in Training Program. The purpose of this article is to update the scientific community on the progress made in the original funding period and to encourage submission of clinical research that addresses 1 or more of the research priority areas of ARLG 2.0
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