20 research outputs found
Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19
IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19.
Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19.
DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 nonâcritically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022).
INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (nâ=â257), ARB (nâ=â248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; nâ=â10), or no RAS inhibitor (control; nâ=â264) for up to 10 days.
MAIN OUTCOMES AND MEASURES The primary outcome was organ supportâfree days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes.
RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ supportâfree days among critically ill patients was 10 (â1 to 16) in the ACE inhibitor group (nâ=â231), 8 (â1 to 17) in the ARB group (nâ=â217), and 12 (0 to 17) in the control group (nâ=â231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ supportâfree days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively).
CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes.
TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570
Study of cross-correlations in traffic networks with applications to perimeter control
A cross-correlation is proposed between network-aggregated density and flow as a natural indicator of traffic phases for two-dimensional road networks. An online estimator of the cross-correlation was studied with the use of empirical data. The result suggests that the measure can be used to identify traffic phases. To understand better the behavior of the true statistical cross-correlation, generic networks were simulated. With homogeneously distributed densities, the simulations suggested that the cross-correlation monotonically decreases with the growth of the mean density and vanishes when the network is at capacity. As a consequence, for such networks, the phase can be identified from a single point on the curve of the cross-correlation versus mean density. A case study of cross-correlationâbased perimeter-control strategies was performed, with gate traffic flowing into the network when the cross-correlation was below a (negative) threshold to improve network flows. The simulation results suggest that even with anisotropic traffic demand, the cross-correlationâbased control strategy can improve network performance, specifically traffic flow and density heterogeneity
Measuring the electrical properties of semiconductor nanowires using terahertz conductivity spectroscopy
Accurately measuring the electronic properties of nanowires is a crucial step in the development of novel semiconductor nanowire-based devices. With this in mind, optical pump-terahertz probe (OPTP) spectroscopy is ideally suited to studies of nanowires
Measuring the electrical properties of semiconductor nanowires using terahertz conductivity spectroscopy
Accurately measuring the electronic properties of nanowires is a crucial step in the development of novel semiconductor nanowire-based devices. With this in mind, optical pumpâterahertz probe (OPTP) spectroscopy is ideally suited to studies of nanowires: it provides non-contact measurement of carrier transport and dynamics at room temperature. OPTP spectroscopy has been used to assess key electrical properties, including carrier lifetime and carrier mobility, of GaAs, InAs and InP nanowires. The measurements revealed that InAs nanowires exhibited the highest mobilities and InP nanowires exhibited the lowest surface recombination velocity
Probing the critical electronic properties of III-V nanowires using optical pump-terahertz probe spectroscopy
Optical pump-terahertz probe spectroscopy was used to study the key electronic properties of GaAs, InAs and InP nanowires at room temperature. Of all nanowires studied, InAs nanowires exhibited the highest mobilities of 6000 cm2V-1s-1. InP nanowires feat
Ultrafast Transient Terahertz Conductivity of Monolayer MoS<sub>2</sub> and WSe<sub>2</sub> Grown by Chemical Vapor Deposition
We have measured ultrafast charge carrier dynamics in monolayers and trilayers of the transition metal dichalcogenides MoS<sub>2</sub> and WSe<sub>2</sub> using a combination of time-resolved photoluminescence and terahertz spectroscopy. We recorded a photoconductivity and photoluminescence response time of just 350 fs from CVD-grown monolayer MoS<sub>2</sub>, and 1 ps from trilayer MoS<sub>2</sub> and monolayer WSe<sub>2</sub>. Our results indicate the potential of these materials as high-speed optoelectronic materials
Ultralow Surface Recombination Velocity in InP Nanowires Probed by Terahertz Spectroscopy
Using transient terahertz photoconductivity measurements,
we have
made noncontact, room temperature measurements of the ultrafast charge
carrier dynamics in InP nanowires. InP nanowires exhibited a very
long photoconductivity lifetime of over 1 ns, and carrier lifetimes
were remarkably insensitive to surface states despite the large nanowire
surface area-to-volume ratio. An exceptionally low surface recombination
velocity (170 cm/s) was recorded at room temperature. These results
suggest that InP nanowires are prime candidates for optoelectronic
devices, particularly photovoltaic devices, without the need for surface
passivation. We found that the carrier mobility is not limited by
nanowire diameter but is strongly limited by the presence of planar
crystallographic defects such as stacking faults in these predominantly
wurtzite nanowires. These findings show the great potential of very
narrow InP nanowires for electronic devices but indicate that improvements
in the crystallographic uniformity of InP nanowires will be critical
for future nanowire device engineering
TRANSRECTAL NEEDLE BIOPSY FOR PROSTATIC CANCERïŒREVIEW OF 75 CASES
Digital examination is a more essential diagnostic method for prostatic disorders and the result obtained is a very important factor for deciding stage of prostatic cancer, too. We performed 108 times transrectal needle biopsy of the prostate in 75 cases during 11 years since 1968 and reviewed them in comparison with digital findings. Accurate rate by digital examination was 72%. The biopsy revealed more extensive cancer than digital findings frequently. In 20 out of T1 and T2 28 cases, the stage should be altered to higher level and in 17 of these, the advanced stage should be considered beyond the prostatic capsule (60.7%). The complication rate was 6.5% being not much higher than previous reports. Possibility of disagreement between digital findings and histopathological diagnosis by needle biopsy should be considered in deciding the stage of the prostatic cancer in order to avoid underestimation in the clinical examinations, which is very common. When a needle biopsy or the prostate is performed, several specimens must be obtained from the suspicious as well as randomly selected areas