The present paper describes a new method utilizing rapid anodization to quickly synthesize high-quality, high aspect ratio, robust titanium dioxide nanotube powders. TiO2 nanotube powders, with a ...typical nanotube outer diameter of approximately 40 nm, wall thickness of approximately 8−15 nm, and length of about 10−35 μm, were synthesized by potentiostatic rapid breakdown anodization of titanium foils in aqueous electrolytes of 0.3 M NaCl or 0.1 M HClO4 under an applied potential of 20 V. High reactivity and ultrahigh reaction rate are cornerstones responsible for periodic release of TiO2 nanotubes into solution and formation of a white precipitate of TiO2 nanotubes. The reaction yield is approximately 4−6 g in less than 3 h, and the approximate cost of the material is $3.50/g, based on the laboratory-scale production. Various characterization techniques, including FESEM, HRTEM, EDX, XRD, XPS, FT-IR, UV−visible diffuse-reflectance, and N2 adsorption, have been used to probe morphology, microstructure, crystallographic, composition, bond configuration, optical properties, and surface area of the nanotubes. XPS and EDX investigations show that nanotubes formed in NaCl/phosphate electrolyte solutions contain a significant amount of phosphorus species, which strongly affects crystallization and phase transformation of TiO2. Namely, phosphate-incorporating nanotubes stabilized the anatase phase, and initiation of the rutile phase was observed at annealing temperatures ≥700 °C. The resulting nanotube powders have a significant level of OH groups with a band gap ranging from 3.04 to 3.23 eV. Our results indicate that rapid breakdown anodization is highly efficient in the production of good-quality TiO2 nanotube powders, which makes it an alternative to well-documented conventional methods.
Robotic-assisted navigation bronchoscopy (RANB) is a novel method to biopsy lung nodules, with initial reports demonstrating excellent accuracy. We aimed to evaluate pooled estimates of diagnostic ...yields and complication rates with RANB by performing a meta-analysis of the available literature.
We searched 3 databases, including PubMed, EmBase, and Web of Science. The resulting abstracts were reviewed by 2 investigators. Analyses were performed using random effects models, and diagnostic yield and complication rates were estimated after the Freeman-Tukey transformation.
A total of 23 articles, comprising 1409 patients and 1541 nodules, were included in the final analysis. Mean ages ranged from 63.2 to 69.3 years. The average size of the nodules ranged between 5.9 and 25.0 mm. Most patients (54.0% to 92.0%) had a current or prior smoking history in studies that reported them (n=8). The pooled diagnostic yield was 81.9% (12 studies, 838 nodules, 95% CI: 83.4%-91.0%), and the pooled sensitivity for malignancy was 87.6% (8 studies, 699 nodules, 95% CI: 81.3%-89.5%). The pooled incidence of pneumothorax rates was 0.60% (95% CI: 0.11%-1.35%). The pooled incidence of major bleeding was <0.01%.
Diagnostic yield for patients with pulmonary nodules undergoing RANB is high, though may be impacted by the prevalence of malignancy, participant selection, and publication bias. Complication rates, including pneumothoraces and bleeding rates, appear low across all studies. If RANB is available, clinicians should consider utilizing this platform to biopsy pulmonary nodules.
Differences in HIV prevalence, access to antiretrovirals and ICU resources may result in wide variation in sepsis mortality in HIV patients. The aim of this study was to perform a meta-analysis to ...quantify the excess risk of sepsis mortality in HIV patients.
A systematic review was performed using three databases. The systemic inflammatory response syndrome criteria was used for the presumptive diagnosis of sepsis. We only included studies that stratified sepsis mortality by HIV serostatus. A meta-analysis was performed using random effects models, with subgroup analyses performed using country income, sepsis severity, and time periods.
17 studies were included, containing 82,905 patients. Sepsis mortality was found to be 28% higher in the HIV positive patients (95% CI 1.13–1.46, p < .01). Relative risk of mortality was higher in patients treated in low-income countries (RR 1.43 in low-income vs. 1.29 in high-income countries). Mortality was more pronounced in HIV patients with severe sepsis (RR 1.32 in severe sepsis vs. RR 1.15 in sepsis).
HIV increases the risk of sepsis mortality compared to seronegative individuals across all time periods and geographic areas. We note that this effect is more pronounced in patients with organ dysfunction.
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•Mortality from sepsis was 28% higher in patients with HIV.•The effect of HIV on mortality was more pronounced in patients with severe sepsis.•Risk of sepsis mortality in HIV was higher in patients in lower income countries.•Risk of sepsis mortality in HIV was higher in the pre-HAART era.
Chromium is commonly found in huge quantities in tannery wastewaters. For this reason, the removal and recovery of the chromium content of tannery wastewaters is crucial for environmental protection ...and economic reasons. Removal and recovery of chromium were carried out by using low-cost potential adsorbents. For this purpose three types of activated carbon; C1, the waste generated from sugar industry as waste products and the others (C2, C3) are commercial granular activated carbon, were used. The adsorption process and extent of adsorption are dependent on the physical and chemical characteristics of the adsorbent, adsorbate and experimental condition. The effect of pH, particle size and different adsorbent on the adsorption isotherm of Cr(III) was studied in batch system. The sorption data fitted well with Langmuir adsorption model. The efficiencies of activated carbon for the removal of Cr(III) were found to be 98.86, 98.6 and 93 % for C1, C2 and C3, respectively. The order of selectivity is C1
>
C2
>
C3 for removal of Cr(III) from tannery wastewater. Carbon “C1” of the highest surface area (520.66
m
2/g) and calcium content (333.3
mg/l) has the highest adsorptive capacity for removal of Cr(III). The results revealed that the trivalent chromium is significantly adsorbed on activated carbon collected from sugar industry as waste products and the method could be used economically as an efficient technique for removal of Cr(III) and purification of tannery wastewaters.
Abstract
Single-qubit gates are essential components of a universal quantum computer. Without selective addressing of individual qubits, scalable implementation of quantum algorithms is extremely ...challenging. When the qubits are discrete points or regions on a lattice, selectively addressing magnetic spin qubits at the nanoscale remains a challenge due to the difficulty of localizing and confining a classical divergence-free field to a small volume of space. Herein we propose a technique for addressing spin qubits using voltage-control of nanoscale magnetism, exemplified by the use of voltage control of magnetic anisotropy. We show that by tuning the frequency of the nanomagnet’s electric field drive to the Larmor frequency of the spins confined to a nanoscale volume, and by modulating the phase of the drive, single-qubit quantum gates with fidelities approaching those for fault-tolerant quantum computing can be implemented. Such single-qubit gate operations require only tens of femto-Joules per gate operation and have lossless, purely magnetic field control. Their physical realization is also straightforward using foundry manufacturing techniques.
We report on the design of an active feedback circuit for charge sensitive amplifiers used for reading out hybrid pixel detectors. The predominant advantages of the proposed feedback over the ...existing solutions are its low noise, stability, and tunability. In addition, the circuit occupies small silicon area, which is crucial for hybrid pixel detectors. This paper presents both the mathematical analysis of the proposed circuit and measurement results obtained with the test structure.
Abstract
Physical Reservoir Computing (PRC) is an unconventional computing paradigm that exploits the nonlinear dynamics of reservoir blocks to perform temporal data classification and prediction ...tasks. Here, we show with simulations that patterned thin films hosting skyrmion can implement energy-efficient straintronic reservoir computing (RC) in the presence of room-temperature thermal perturbation. This RC block is based on strain-induced nonlinear breathing dynamics of skyrmions, which are coupled to each other through dipole and spin-wave interaction. The nonlinear and coupled magnetization dynamics were exploited to perform temporal data classification and prediction. Two performance metrics, namely Short-Term Memory (STM) and Parity Check (PC) capacity are studied and shown to be promising (4.39 and 4.62 respectively), in addition to showing it can classify sine and square waves with 100% accuracy. These demonstrate the potential of such skyrmion based PRC. Furthermore, our study shows that nonlinear magnetization dynamics and interaction through spin-wave and dipole coupling have a strong influence on STM and PC capacity, thus explaining the role of physical interaction in a dynamical system on its ability to perform RC.
We describe our initial approach and progress towards a reliable and useful technique to connect multiple flexible superconducting cables using a cable-to-cable connector. The test structure ...comprises multiple components, including flexible thin-film superconducting cables, a bridging connector, a silicon well chip, and a polyimide membranes with Cu pillars. The thin-film superconducting cables used in this work contain 12 parallel Nb lines. A bridging connector which was used to connect two superconducting cables had a stripline structure with 12 parallel superconducting Nb transmission lines with 300 <inline-formula><tex-math notation="LaTeX">\mu</tex-math></inline-formula>m pitch among them. A silicon well chip and a polyimide membrane with Cu pillars have been used in the assembly for high-precision micro-mechanical alignment and to apply uniform pressure on the contact points of cables and the bridging connector. DC resistances of signal traces of connected flexible cables were measured at temperature ranging from 293 K to 4.2 K in an evacuated cryogenic environment. We present the details of the design, fabrication, assembly, and test results, which show that this is a promising cable-to-cable connection approach.
There are limited data on the epidemiology of Non-tuberculous mycobacteria (NTM) infections among patients with COPD, particularly in the veteran population. This study examined the prevalence, ...incidence, and mortality of pulmonary NTM infections among veterans with COPD population in the United States.
We analyzed nationwide data from Veterans Affairs Hospitals from 2001 to 2015. First, we determined the incidence and prevalence rates and geographic distribution of NTM infections among veterans with COPD and then we evaluated the association between NTM infections with mortality among veterans with COPD. Pulmonary NTM and COPD diagnosis were defined based on charting claims for each condition on ≥2 occasions and ≥30 days apart. COPD diagnoses had to precede diagnosis of NTM. Cox Proportional-Hazards Regression was performed to determine the dependency of survival time of COPD patients with NTM.
The incidence and prevalence rates of NTM rose over the study period, with a sharp rise in incidence after 2012. The areas with the highest NTM period prevalence were Puerto Rico (370), followed by Florida (351) and District of Columbia (309) in 100,000 COPD population. Mortality registered for those patients with COPD Patients and NTM infection was 1.43 times higher compared to those that were uninfected.
NTM rates have been increasing in veterans with COPD since 2012. NTM infection is associated with increased risk of mortality. This highlights the importance of identifying preventable risk factors associated with NTM infections in subjects with COPD.
