Probing ultrafast carrier dynamics and nonlinear absorption and refraction in core-shell silicon nanowires

We investigate the relaxation dynamics of photogenerated carriers in silicon nanowires consisting of a crystalline core and a surrounding amorphous shell, using femtosecond time-resolved differential reflectivity and transmission spectroscopy at photon energies of 3.15 eV and 1.57 eV. The complex behavior of the differential transmission and reflectivity transients is the mixed contributions from the crystalline core and the amorphous silicon on the nanowire surface and the substrate where competing effects of state filling and photoinduced absorption govern the carrier dynamics. Faster relaxation rates are observed on increasing the photo-generated carrier density. Independent experimental results on crystalline silicon-on-sapphire help us in separating the contributions from the carrier dynamics in crystalline core and the amorphous regions in the nanowire samples. Further, single beam z-scan nonlinear transmission experiments at 1.57 eV in both open and close aperture configurations yield two-photon absorption coefficient \$beta$ (~3 cm/GW) and nonlinear refraction coefficient \$gamma$ (-2.5x10^-4 cm2/GW).Comment: 6 pages, 6 figure

Cross-cultural psychometric assessment of an appetite questionnaire for patients with cancer

Objective: To evaluate the psychometric properties, along with cross-cultural invariance analysis, of the Cancer Appetite and Symptom Questionnaire (CASQ). Method: Data from 555 United Kingdom (UK) cancer patients were used to evaluate the psychometric properties of the CASQ. Construct validity was assessed through factorial and convergent validity. We conducted a confirmatory factor analysis using as indices the chi-square ratio by degrees of freedom (χ2/df), the comparative fit index (CFI), the goodness of fit index (GFI), and the root mean square error of approximation (RMSEA). Convergent validity was estimated by the items’ average variance extracted (AVE). Reliability was estimated by composite reliability and internal consistency. Factorial invariance analysis of the CASQ was evaluated by multigroup analysis (∆χ2) using the UK and Brazilian samples. Results: All items showed adequate psychometric sensitivity in the UK sample. One item was removed and four correlations were included between errors with an appropriate fit of the model (χ2/df = 2.674, CFI = 0.966, GFI = 0.964, RMSEA = 0.055). The reliability of the CASQ was adequate and the convergent validity was low. The factorial structure of the CASQ differed across countries, and a lack of measurement invariance for the two countries was observed (λ: ∆χ2 = 64.008, p < 0.001; i: ∆χ2 = 3515.047, p < 0.001; Res: ∆χ2 = 4452.504, p < 0.001). Conclusion: The CASQ showed adequate psychometric properties in the UK sample. The ability to estimate loss of appetite and the presence of symptoms was different between UK and Brazilian patients

An international Delphi consensus regarding best practice recommendations for hyperkalaemia across the cardiorenal spectrum.

AIMS: Renin-angiotensin-aldosterone system inhibitors (RAASi) are guideline-recommended therapy for individuals with cardiorenal disease. They are associated with increased risk of hyperkalaemia, a common and life-threatening disorder for this population. RAASi-induced hyperkalaemia often leads to dose reduction or discontinuation, reducing cardiorenal protection. Guideline recommendations differ between specialties for the clinical management of hyperkalaemia. Using a modified Delphi method, we developed consensus recommendations for optimal management of hyperkalaemia in adults with cardiorenal disease. METHODS AND RESULTS: An international steering group of cardiologists and nephrologists developed 39 statements regarding hyperkalaemia care, including risk factors and risk stratification, prevention, correction, and cross-specialty coordination. Consensus was determined by agreement on an online questionnaire administered to cardiorenal specialists across Europe and North America. The threshold for consensus agreement was established a priori by the steering group at 67%. Across November 2021, 520 responses were received from Canada (n = 50), France (n = 50), Germany (n = 54), Italy (n = 58), Spain (n = 57), the UK (n = 49), and the US (n = 202); 268 from cardiologists and 252 from nephrologists. Twenty-nine statements attained very high agreement (≥90%) and 10 attained high agreement (≥67%-<90%), with strong alignment between cardiologists and nephrologists. CONCLUSION: A high degree of consensus regarding hyperkalaemia evaluation and management exists among healthcare professionals. Based on high levels of agreement, the steering group derived six key recommendations for hyperkalaemia prevention and management in people with cardiorenal disease. Future studies examining the quality of hyperkalaemia care delivery are required

Acute kidney disease and renal recovery : consensus report of the Acute Disease Quality Initiative (ADQI) 16 Workgroup

Consensus definitions have been reached for both acute kidney injury (AKI) and chronic kidney disease (CKD) and these definitions are now routinely used in research and clinical practice. The KDIGO guideline defines AKI as an abrupt decrease in kidney function occurring over 7 days or less, whereas CKD is defined by the persistence of kidney disease for a period of > 90 days. AKI and CKD are increasingly recognized as related entities and in some instances probably represent a continuum of the disease process. For patients in whom pathophysiologic processes are ongoing, the term acute kidney disease (AKD) has been proposed to define the course of disease after AKI; however, definitions of AKD and strategies for the management of patients with AKD are not currently available. In this consensus statement, the Acute Disease Quality Initiative (ADQI) proposes definitions, staging criteria for AKD, and strategies for the management of affected patients. We also make recommendations for areas of future research, which aim to improve understanding of the underlying processes and improve outcomes for patients with AKD

Multiplicity Distributions and Charged-neutral Fluctuations

Results from the multiplicity distributions of inclusive photons and charged particles, scaling of particle multiplicities, event-by-event multiplicity fluctuations, and charged-neutral fluctuations in 158$\cdot A$ GeV Pb+Pb collisions are presented and discussed. A scaling of charged particle multiplicity as $N_{part}^{1.07\pm 0.05}$ and photons as $N_{part}^{1.12\pm 0.03}$ have been observed, indicating violation of naive wounded nucleon model. The analysis of localized charged-neutral fluctuation indicates a model-independent demonstration of non-statistical fluctuations in both charged particles and photons in limited azimuthal regions. However, no correlated charged-neutral fluctuations are observed.Comment: Talk given at the International Symposium on Nuclear Physics (ISNP-2000), Mumbai, India, 18-22 Dec 2000, Proceedings to be published in Pramana, Journal of Physic

Azimuthal anisotropy and correlations at large transverse momenta in p+pp+p and Au+Au collisions at sNN\sqrt{s_{_{NN}}}= 200 GeV

Results on high transverse momentum charged particle emission with respect to the reaction plane are presented for Au+Au collisions at $\sqrt{s_{_{NN}}}$= 200 GeV. Two- and four-particle correlations results are presented as well as a comparison of azimuthal correlations in Au+Au collisions to those in $p+p$ at the same energy. Elliptic anisotropy, $v_2$, is found to reach its maximum at $p_t \sim 3$ GeV/c, then decrease slowly and remain significant up to $p_t\approx 7$ -- 10 GeV/c. Stronger suppression is found in the back-to-back high-$p_t$ particle correlations for particles emitted out-of-plane compared to those emitted in-plane. The centrality dependence of $v_2$ at intermediate $p_t$ is compared to simple models based on jet quenching.Comment: 4 figures. Published version as PRL 93, 252301 (2004

Azimuthal anisotropy in Au+Au collisions at sqrtsNN = 200 GeV

The results from the STAR Collaboration on directed flow (v_1), elliptic flow (v_2), and the fourth harmonic (v_4) in the anisotropic azimuthal distribution of particles from Au+Au collisions at sqrtsNN = 200 GeV are summarized and compared with results from other experiments and theoretical models. Results for identified particles are presented and fit with a Blast Wave model. Different anisotropic flow analysis methods are compared and nonflow effects are extracted from the data. For v_2, scaling with the number of constituent quarks and parton coalescence is discussed. For v_4, scaling with v_2^2 and quark coalescence is discussed.Comment: 26 pages. As accepted by Phys. Rev. C. Text rearranged, figures modified, but data the same. However, in Fig. 35 the hydro calculations are corrected in this version. The data tables are available at http://www.star.bnl.gov/central/publications/ by searching for "flow" and then this pape

Rapidity and Centrality Dependence of Proton and Anti-proton Production from Au+Au Collisions at sqrt(sNN) = 130GeV

We report on the rapidity and centrality dependence of proton and anti-proton transverse mass distributions from Au+Au collisions at sqrt(sNN) = 130GeV as measured by the STAR experiment at RHIC. Our results are from the rapidity and transverse momentum range of |y|<0.5 and 0.35 <p_t<1.00GeV/c. For both protons and anti-protons, transverse mass distributions become more convex from peripheral to central collisions demonstrating characteristics of collective expansion. The measured rapidity distributions and the mean transverse momenta versus rapidity are flat within |y|<0.5. Comparisons of our data with results from model calculations indicate that in order to obtain a consistent picture of the proton(anti-proton) yields and transverse mass distributions the possibility of pre-hadronic collective expansion may have to be taken into account.Comment: 4 pages, 3 figures, 1 table, submitted to PR

Limits on WWZ and WW\gamma couplings from p\bar{p}\to e\nu jj X events at \sqrt{s} = 1.8 TeV

We present limits on anomalous WWZ and WW-gamma couplings from a search for WW and WZ production in p-bar p collisions at sqrt(s)=1.8 TeV. We use p-bar p -> e-nu jjX events recorded with the D0 detector at the Fermilab Tevatron Collider during the 1992-1995 run. The data sample corresponds to an integrated luminosity of 96.0+-5.1 pb^(-1). Assuming identical WWZ and WW-gamma coupling parameters, the 95% CL limits on the CP-conserving couplings are -0.33<lambda<0.36 (Delta-kappa=0) and -0.43<Delta-kappa<0.59 (lambda=0), for a form factor scale Lambda = 2.0 TeV. Limits based on other assumptions are also presented.Comment: 11 pages, 2 figures, 2 table