Processing, microstructure and mechanical properties of bimodal size SiCp reinforced AZ31B magnesium matrix composites

AbstractThe bimodal size SiC particulates (SiCp) reinforced magnesium matrix composites with different ratios of micron SiCp and nano SiCp (M-SiCp:N-SiCp = 14.5:0.5, 14:1, and 13.5:1.5) were prepared by semisolid stirring assisted ultrasonic vibration method. The AZ31B alloy and all as-cast SiCp/AZ31B composites were extruded at 350 °C with the ratio of 12:1. Microstructural characterization of the extruded M14 + N1 (M-SiCp:N-SiCp = 14:1) composite revealed the uniform distribution of bimodal size SiCp and significant grain refinement. Optical Microscopy(OM) observation showed that, compared with the M14.5 + N0.5 (M-SiCp:N-SiCp = 14.5:0.5) composite, there are more recrystallized grains in M14 + N1 (M-SiCp:N-SiCp = 14:1) and M13.5 + N1.5 (M-SiCp:N-SiCp = 13.5:1.5) composites, but in comparison to the M13.5 + N1.5 composite, the average grain size of the M14 + N1 composite is slightly decreased. The evaluation of mechanical properties indicated that the yield strength and ultimate tensile strength of the M14 + N1 composite were obviously increased compared with other composites

Robot-assisted Radical Cystectomy Versus Open Radical Cystectomy: A Systematic Review and Meta-analysis of Perioperative, Oncological, and Quality of Life Outcomes Using Randomized Controlled Trials

© 2023 The Authors. Published by Elsevier B.V. on behalf of European Association of Urology. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)Context: Differences in recovery, oncological, and quality of life (QoL) outcomes between open radical cystectomy (ORC) and robot-assisted radical cystectomy (RARC) for patients with bladder cancer are unclear.  Objective: This review aims to compare these outcomes within randomized trials of ORC and RARC in this context. The primary outcome was the rate of 90-d perioperative events. The secondary outcomes included operative, pathological, survival, and health-related QoL (HRQoL) measures.  Evidence acquisition: Systematic literature searches of MEDLINE, Embase, Web of Science, and clinicaltrials.gov were performed up to May 31, 2022.  Evidence synthesis: Eight trials, reporting 1024 participants, were included. RARC was associated with a shorter hospital length of stay (LOS; mean difference [MD] 0.21, 95% confidence interval [CI] 0.03–0.39, p = 0.02) than and similar complication rates to ORC. ORC was associated with higher thromboembolic events (odds ratio [OR] 1.84, 95% CI 1.02–3.31, p = 0.04). ORC was associated with more blood loss (MD 322 ml, 95% CI 193–450, p < 0.001) and transfusions (OR 2.35, 95% CI 1.65–3.36, p < 0.001), but shorter operative time (MD 76 min, 95% CI 39–112, p < 0.001) than RARC. No differences in lymph node yield (MD 1.07, 95% CI –1.73 to 3.86, p = 0.5) or positive surgical margin rates (OR 0.95, 95% CI 0.54–1.67, p = 0.9) were present. RARC was associated with better physical functioning or well-being (standardized MD 0.47, 95% CI 0.29–0.65, p < 0.001) and role functioning (MD 8.8, 95% CI 2.4–15.1, p = 0.007), but no improvement in overall HRQoL. No differences in progression-free survival or overall survival were seen. Limitations may include a lack of generalization given trial patients.  Conclusions: RARC offers various perioperative benefits over ORC. It may be more suitable in patients wishing to avoid blood transfusion, those wanting a shorter LOS, or those at a high risk of thromboembolic events.  Patient summary: This study compares robot-assisted keyhole surgery with open surgery for bladder cancer. The robot-assisted approach offered less blood loss, shorter hospital stays, and fewer blood clots. No other differences were seen.Peer reviewe

Partial wave analysis of J/\psi \to \gamma \phi \phi

Using $5.8 \times 10^7 J/\psi$ events collected in the BESII detector, the radiative decay $J/\psi \to \gamma \phi \phi \to \gamma K^+ K^- K^0_S K^0_L$ is studied. The $\phi\phi$ invariant mass distribution exhibits a near-threshold enhancement that peaks around 2.24 GeV/$c^{2}$. A partial wave analysis shows that the structure is dominated by a $0^{-+}$ state ($\eta(2225)$) with a mass of $2.24^{+0.03}_{-0.02}{}^{+0.03}_{-0.02}$ GeV/$c^{2}$ and a width of $0.19 \pm 0.03^{+0.06}_{-0.04}$ GeV/$c^{2}$. The product branching fraction is: $Br(J/\psi \to \gamma \eta(2225))\cdot Br(\eta(2225)\to \phi\phi) = (4.4 \pm 0.4 \pm 0.8)\times 10^{-4}$.Comment: 11 pages, 4 figures. corrected proof for journa

Search for the Rare Decays J/Psi --> Ds- e+ nu_e, J/Psi --> D- e+ nu_e, and J/Psi --> D0bar e+ e-

We report on a search for the decays J/Psi --> Ds- e+ nu_e + c.c., J/Psi --> D- e+ nu_e + c.c., and J/Psi --> D0bar e+ e- + c.c. in a sample of 5.8 * 10^7 J/Psi events collected with the BESII detector at the BEPC. No excess of signal above background is observed, and 90% confidence level upper limits on the branching fractions are set: B(J/Psi --> Ds- e+ nu_e + c.c.)<4.8*10^-5, B(J/Psi --> D- e+ nu_e + c.c.) D0bar e+ e- + c.c.)<1.1*10^-5Comment: 10 pages, 4 figure

Measurements of the observed cross sections for e+e−→e^+e^-\to exclusive light hadrons containing π0π0\pi^0\pi^0 at s=3.773\sqrt s= 3.773, 3.650 and 3.6648 GeV

By analyzing the data sets of 17.3, 6.5 and 1.0 pb$^{-1}$ taken, respectively, at $\sqrt s= 3.773$, 3.650 and 3.6648 GeV with the BES-II detector at the BEPC collider, we measure the observed cross sections for $e^+e^-\to \pi^+\pi^-\pi^0\pi^0$, $K^+K^-\pi^0\pi^0$, $2(\pi^+\pi^-\pi^0)$, $K^+K^-\pi^+\pi^-\pi^0\pi^0$ and $3(\pi^+\pi^-)\pi^0\pi^0$ at the three energy points. Based on these cross sections we set the upper limits on the observed cross sections and the branching fractions for $\psi(3770)$ decay into these final states at 90% C.L..Comment: 7 pages, 2 figure

Direct Measurements of Absolute Branching Fractions for D0 and D+ Inclusive Semimuonic Decays

By analyzing about 33 $\rm pb^{-1}$ data sample collected at and around 3.773 GeV with the BES-II detector at the BEPC collider, we directly measure the branching fractions for the neutral and charged $D$ inclusive semimuonic decays to be $BF(D^0 \to \mu^+ X) =(6.8\pm 1.5\pm 0.7)$ and $BF(D^+ \to \mu^+ X) =(17.6 \pm 2.7 \pm 1.8)$, and determine the ratio of the two branching fractions to be $\frac{BF(D^+ \to \mu^+ X)}{BF(D^0 \to \mu^+ X)}=2.59\pm 0.70 \pm 0.25$

Measurements of the Mass and Full-Width of the ηc\eta_c Meson

In a sample of 58 million $J/\psi$ events collected with the BES II detector, the process J/$\psi\to\gamma\eta_c$ is observed in five different decay channels: $\gamma K^+K^-\pi^+\pi^-$, $\gamma\pi^+\pi^-\pi^+\pi^-$, $\gamma K^\pm K^0_S \pi^\mp$ (with $K^0_S\to\pi^+\pi^-$), $\gamma \phi\phi$ (with $\phi\to K^+K^-$) and $\gamma p\bar{p}$. From a combined fit of all five channels, we determine the mass and full-width of $\eta_c$ to be $m_{\eta_c}=2977.5\pm1.0 ({stat.})\pm1.2 ({syst.})$ MeV/$c^2$ and $\Gamma_{\eta_c} = 17.0\pm3.7 ({stat.})\pm7.4 ({syst.})$ MeV/$c^2$.Comment: 9 pages, 2 figures and 4 table. Submitted to Phys. Lett.

A Measurement of Psi(2S) Resonance Parameters

Cross sections for e+e- to hadons, pi+pi- J/Psi, and mu+mu- have been measured in the vicinity of the Psi(2S) resonance using the BESII detector operated at the BEPC. The Psi(2S) total width; partial widths to hadrons, pi+pi- J/Psi, muons; and corresponding branching fractions have been determined to be Gamma(total)= (264+-27) keV; Gamma(hadron)= (258+-26) keV, Gamma(mu)= (2.44+-0.21) keV, and Gamma(pi+pi- J/Psi)= (85+-8.7) keV; and Br(hadron)= (97.79+-0.15)%, Br(pi+pi- J/Psi)= (32+-1.4)%, Br(mu)= (0.93+-0.08)%, respectively.Comment: 8 pages, 6 figure

Direct Measurements of the Branching Fractions for D0→K−e+νeD^0 \to K^-e^+\nu_e and D0→π−e+νeD^0 \to \pi^-e^+\nu_e and Determinations of the Form Factors f+K(0)f_{+}^{K}(0) and f+π(0)f^{\pi}_{+}(0)

The absolute branching fractions for the decays $D^0 \to K^-e ^+\nu_e$ and $D^0 \to \pi^-e^+\nu_e$ are determined using $7584\pm 198 \pm 341$ singly tagged $\bar D^0$ sample from the data collected around 3.773 GeV with the BES-II detector at the BEPC. In the system recoiling against the singly tagged $\bar D^0$ meson, $104.0\pm 10.9$ events for $D^0 \to K^-e ^+\nu_e$ and $9.0 \pm 3.6$ events for $D^0 \to \pi^-e^+\nu_e$ decays are observed. Those yield the absolute branching fractions to be $BF(D^0 \to K^-e^+\nu_e)=(3.82 \pm 0.40\pm 0.27)$ and $BF(D^0 \to \pi^-e^+\nu_e)=(0.33 \pm 0.13\pm 0.03)$. The vector form factors are determined to be $|f^K_+(0)| = 0.78 \pm 0.04 \pm 0.03$ and $|f^{\pi}_+(0)| = 0.73 \pm 0.14 \pm 0.06$. The ratio of the two form factors is measured to be $|f^{\pi}_+(0)/f^K_+(0)|= 0.93 \pm 0.19 \pm 0.07$.Comment: 6 pages, 5 figure

Study of J/psi decays to Lambda Lambdabar and Sigma0 Sigma0bar

The branching ratios and Angular distributions for J/psi decays to Lambda Lambdabar and Sigma0 Sigma0bar are measured using BESII 58 million J/psi.Comment: 11 pages, 5 figure