Search

We report the studies of structure and properties of a quasi-one-dimensional (quasi-1D) compound ${\rm BaTiS}_{3}$ BaTiS 3 under pressure. The poly-crystalline samples are synthesized by solid-state reaction method and single-crystalline samples are produced by chemical vapor transport method. The XRD measurement under ambient pressure confirms the hexagonal structure, which consists of face-sharing octahedral ${\rm TiS}_{6}$ TiS 6 chains along c-axis and displays a quasi-1D feature. When applying pressure, the synchrotron X-ray diffraction experiments show that the sample undergoes a phase transition from hexagonal phase to orthorhombic phase at around 10 GPa due to the zig–zag deformation of ${\rm TiS}_{6}$ TiS 6 chains, while the quasi-1D structure is reserved. At ambient pressure, ${\rm BaTiS}_{3}$ BaTiS 3 exhibits an insulating behavior with a band gap about 0.273 eV. When applying pressure, the sample undergoes a crossover from insulator to metal due to the enhancement of inter-chain electron hopping. [ABSTRACT FROM AUTHOR]

The dependence of thermoluminescence (TL) and optically stimulated luminescence (OSL) properties of LiMgPO4:Tb,Sm,B samples prepared by the high-temperature solid-state method on maximum heating temperatures was investigated for the first time. The TL glow curves showed the ratio of peak 3 to peak 2 increased with the increase of maximum heating temperature. The influence of OSL on maximum heating temperatures showed that the sensitivity of OSL reached the maximum at the maximum heating temperature of 1000°C, which is 11.6 times higher than that of 800 °C. The relative standard deviation of the repeatability is less than 1.5% regardless of the maximum heating temperature. The minimum measurable dose (MMD) could be significantly improved by optimizing OSL parameters, such as maximum heating temperature and readout time. The MMD as low as 0.31 µGy has been achieved. The residual OSL is up to 92.3% after irradiation for 24 h. LiMgPO4:Tb,Sm,B is highly sensitive to the maximum heating temperature. Considering fast decay time, high OSL sensitivity, good repeatability, low MMD and little fading, it is recommended that the maximum heating temperature of LiMgPO4:Tb,Sm,B is 1000°C. LiMgPO4:Tb,Sm,B has great potential for daily personal and environmental cumulative dose monitoring. [ABSTRACT FROM AUTHOR]

Recent advances in electrochemical methods promise a more sustainable recycling of rare earth elements (REEs) from discarded NdFeB permanent magnets. The demand for NdFeB magnets for clean energy applications is rapidly increasing, motivating recycling efforts to diversify REE supply. The main electrochemical steps include the selective dissolution of REE-rich phases at the anode and the reduction of REE ions at the cathode. Pretreatment with demagnetization, mechanical size reduction, and leaching contributes to the release and concentration of REEs. Thermal demagnetization and mechanical crushing make the magnets brittle and improve the penetration of leaching agents. Acid leaching dissolves the REEs, but also dissolves the iron. To facilitate the extraction of REEs at high temperatures, molten salt electrolytes such as chlorides are used, while ionic liquids allow extraction under milder conditions, but with the caveat of possible decomposition during the process. Aqueous solutions have been most thoroughly investigated due to their versatility and affordability. Fluoride-based molten salt electrolytes effectively dissolve RREs and provide a stable environment for hightemperature electrodeposition, improving the efficiency and sustainability of rare earth element recovery. To isolate highpurity REE oxides and metals, additional processing is required using techniques such as solvent extraction, selective precipitation, and electroseparation. Key factors for optimal electrochemical recycling are maximizing selectivity for REEs, minimizing energy consumption and waste generation, and simplifying integration. Although technical challenges remain, recent advances show that electrochemical technologies can improve the sustainability of recycling critical REEs from permanent magnets. [ABSTRACT FROM AUTHOR]

In this paper, we propose a penalized weighted quantile estimating equations (PWQEEs) method to obtain sparse, robust and efficient estimators for the quantile regression with longitudinal data. The PWQEE incorporates the within correlations in the longitudinal data by Gaussian copulas and can also down-weight the high leverage points in covariates to achieve double-robustness to both the non-normal distributed errors and the contaminated covariates. To overcome the obstacles of discontinuity of the PWQEE and nonconvex optimization, a local distribution smoothing method and the minimization–maximization algorithm are proposed. The asymptotic properties of the proposed method are also proved. Furthermore, finite sample performance of the PWQEE is illustrated by simulation studies and a real-data example. [ABSTRACT FROM AUTHOR]

To understand the living conditions, changes in the service user profile, and needs of vulnerable migrants trying to access healthcare in the early stages of the COVID-19 pandemic. Mixed methods study; using quantitative questionnaire data collected from migrant service users of Doctors of the World UK (DOTW UK) with qualitative data from free-text notes. DOTW UK provides drop-in clinics to vulnerable migrants. Consultations switched to remote during the UK's first lockdown. We compared patient profile, well-being, healthcare access and reason for consultations of individuals attending the virtual clinic between March and September 2020 to those of the prepandemic periods between 2011 and 2018. During the pandemic, consultations dropped to under half of the prepandemic numbers, with the shift to remote consultations attracting more users outside of London. DOTW UK's user base changed to include a greater proportion of asylum seekers, younger adults (18–34) and individuals reporting good health. Socio-economic conditions and housing stability deteriorated for the majority of users. Those in the greatest need of healthcare appeared to be less able to access remote services. General practitioner (GP) registration remained the most common reason for contacting the virtual clinic with a lack of knowledge of the healthcare system being the main barrier to access. The shift to virtual consultations may have exacerbated existing inequalities in healthcare access for vulnerable migrants. Given that many clinical services continue to operate remotely, it is important to consider the impact such actions have on vulnerable migrants and find ways to support access. [ABSTRACT FROM AUTHOR]

Sensing and classification of drought stress levels are very important to agricultural production. In this work, rice drought stress levels were classified based on the commonly used chlorophyll a fluorescence (ChlF) parameter (Fv/Fm), feature data (induction features), and the whole OJIP induction (induction curve) by using a Support Vector Machine (SVM). The classification accuracies were compared with those obtained by the K-Nearest Neighbors (KNN) and the Ensemble model (Ensemble) correspondingly. The results show that the SVM can be used to classify drought stress levels of rice more accurately compared to the KNN and the Ensemble and the classification accuracy (86.7%) for the induction curve as input is higher than the accuracy (43.9%) with Fv/Fm as input and the accuracy (72.7%) with induction features as input. The results imply that the induction curve carries important information on plant physiology. This work provides a method of determining rice drought stress levels based on ChlF. [ABSTRACT FROM AUTHOR]

In this work, a spintronic sensor based microwave holographic imaging system is developed, demonstrating the feasibility of microwave holographic imaging applications using a spintronic microwave sensor. The high sensitivity of the microwave phase measurement allows the coherent imaging of the target reconstructed in noise environments. Adapting the broadband measurement, not only the shape but also the distance of target can be determined, which implies that a three-dimensional imaging is achievable using a spintronic device. [ABSTRACT FROM AUTHOR]

Purpose: Cytomegalovirus retinitis (CMVR) is a serious and potentially sight-threatening infection in immunocompromised individuals. Strategies for the management of drug-resistant CMVR are described. Methods: A case of severe bilateral CMVR in a single lung transplant patient, with UL97 mutation conferring ganciclovir-resistance, is presented. Treatment with standard antiviral agent and adjuvant leflunomide, immunosuppression modifications (calcineurin inhibitors and corticosteroid), intravitreal antiviral therapy and novel use of CMV-immunoglobulin is described. A literature review to support drug-resistant CMVR management is presented. Results: Severe and progressive CMV retinitis was refractory to intravitreal foscarnet and systemic leflunomide. Drug-toxicity restricted systemic antiviral therapy options. The use of combined leflunomide and CMV-immunoglobulins, in the absence of viremia, has not been previously reported. Loss of ganciclovir-resistance was eventually observed permitting successful treatment with systemic and intravitreal ganciclovir. Conclusions: Drug-resistant CMVR is a complex clinical challenge. Multiple systemic and local treatment strategies may be necessary but toxicity, resistance, and co-morbidities may severely restrict available options. [ABSTRACT FROM AUTHOR]

Aim: 3‐Phenyllactic acid (3‐PLA) has been widely used in food and material industries. Three Lactobacillus crustorum strains have shown greater 3‐PLA production ability in our previous study. The objectives of this study were to further improve 3‐PLA yields in batch and continuous fermentation systems using of free‐whole‐cells of the three L. crustorum strains. Materials and Results: The fermentation conditions of free‐whole‐cells of the three L. crustorum strains for 3‐PLA production were optimized. Among these strains, L. crustorum NWAFU 1078 showed excellent reusability and significantly (P < 0·05) greater 3‐PLA production ability than the other strains after 10th recycle. The strain possesses three l‐lactate dehydrogenase and three d‐lactate dehydrogenase catalysing 3‐PLA production from phenylpyruvic acid (PPA). Under the optimal conditions, the strain produced 15·2 mmol l−1 3‐PLA (76% PPA conversion rate) in a batch fermentation system and 6·5 mmol l−1 h−1 3‐PLA (55% PPA conversion rate) in a continuous fermentation system using a 0·6 dilution rate. Conclusions: Free‐whole‐cells of L. crustorum NWAFU 1078 showed excellent reusability and higher 3‐PLA yields under optimal biotransformation conditions in both batch and continuous fermentation systems. Significance and Impact of the Study: This study provides the possibility to use the free‐whole‐cells of L. crustorum NWAFU 1078 as a biocatalyst for effective production of 3‐PLA. [ABSTRACT FROM AUTHOR]

Low-cycle fatigue properties and uniaxial ratcheting behavior of a 7050-T6 aluminum alloy were investigated by a non-symmetric cycle stress tests at the normal temperature. The low-cycle fatigue behavior of the alloy was evaluated. The effect of the stress rate, stress amplitudes, and mean stresses on its ratcheting performance was discussed. Considering the ratcheting effect and special working conditions that large mean stresses and small stress amplitudes, based on the same properties under loading, a new fatigue life prediction empirical equation was proposed to estimate the ratcheting life. The results prove that the ratcheting strain of the alloy depends on the stress amplitudes and mean stresses, whereas the stress rate almost has no effect on the ratcheting behavior on account of the rate-independent feature of the material. This equation can give a precise estimate of the ratcheting behavior of large mean stresses and their small amplitudes. [ABSTRACT FROM AUTHOR]

By the mixed-ligand approach, a new coordination polymer with the chemical formula [Cd(bpydb)(bimb)(H2O)](H2O)3(1, H2bpydb = 4,4′-([2,4′-bipyridine]-2′,6′-diyl)dibenzoic acid, bimb = 5,5′-bis(1H-benzo[d]imidazol-2-yl)-2,2′-bipyridine) is successfully prepared via a hydrothermal reaction of Cd(NO3)4H2O, H2bpydb, and bimb in the presence of NaOH as the pH modulator. Furthermore, we use an ultrasonic method to obtain nanoparticles of 1 with an average thickness of 126 nm. To evaluate the antiinflammatory effect of the compound against inflammatory metrorrhagia, the activation of NF-κb signal pathway is measured by RT-PCR. Furthermore, ELSA is used in this research to detect the IL-1β and IL-18 content. [ABSTRACT FROM AUTHOR]

Photoconductive detectors are convenient devices for detecting pulsed terahertz radiation. We have optimized Fe+ ion-damaged InP materials for photoconductive detector signal to noise performance using dual-energy doses in the range from 2.5×1012 to 1.0×1016 cm-2. Ion implantation allowed the production of semiconducting materials with free-carrier lifetimes between 0.5 and 2.1 ps, which were measured by optical pump terahertz probe spectroscopy. The time resolved photoconductivity of the detector substrates was acquired as a function of time after excitation by 2 nJ pulses from a laser oscillator. These data, when combined with a deconvolution algorithm, provide an excellent spectral response correction to the raw photocurrent signal recorded by the photoconductive detectors. [ABSTRACT FROM AUTHOR]

The defect structures in HgTe/CdTe superlattices (SLs) on CdTe/Si(211)B substrates grown by molecular-beam epitaxy have been investigated using (scanning) transmission electron microscopy and electron energy loss spectroscopy. Straight Hg-rich defects perpendicular to the SLs have been observed near the substrate while Frank dislocation loops (FDLs) are seen far from the substrate. The Hg-rich defects exhibit only a compositional variation with no significant atomic shift, and can be considered to be a remnant of a FDL which has climbed by thermal diffusion during the growth. [ABSTRACT FROM AUTHOR]

We have investigated the defect structure in pure Co-doped and (Co, Nb)-doped TiO2 (anatase) thin films grown by pulsed laser deposition on (001) single crystal LaAlO3. Although both films exhibit room temperature ferromagnetism, dilute Nb doping significantly improves the conductivity and microstructure of the TiO2 (anatase) thin film at the cost of a lower saturation magnetization. Z-contrast imaging and electron-energy-loss-spectroscopy study in the scanning transmission electron microscope show cluster-free microstructure in the (Co, Nb)-doped thin film although Co is enriched into the surface and forms a CoxTi1-x-yNbyO2-δ phase. In contrast, metallic Co, rutile TiO2, and cobalt oxide nanoparticles combined with some crystallographic shear defect structures are observed in the pure Co-doped thin film. The magnetic behavior in each film can be explained with the presence of these defect states or second phases. [ABSTRACT FROM AUTHOR]

In this work, rapid thermal annealing was performed on InGaAs/GaAs quantum dot infrared photodetectors (QDIPs) at different temperatures. The photoluminescence showed a blueshifted spectrum in comparison with the as-grown sample when the annealing temperature was higher than 700 °C, as a result of thermal interdiffusion of the quantum dots (QDs). Correspondingly, the spectral response from the annealed QDIP exhibited a redshift. At the higher annealing temperature of 800 °C, in addition to the largely redshifted photoresponse peak of 7.4 μm (compared with the 6.1 μm of the as-grown QDIP), a high energy peak at 5.6 μm (220 meV) was also observed, leading to a broad spectrum linewidth of 40%. This is due to the large interdiffusion effect which could greatly vary the composition of the QDs and thus increase the relative optical absorption intensity at higher energy. The other important detector characteristics such as dark current, peak responsivity, and detectivity were also measured. It was found that the overall device performance was not affected by low annealing temperature, however, for high annealing temperature, some degradation in device detectivity (but not responsivity) was observed. This is a consequence of increased dark current due to defect formation and increased ground state energy. [ABSTRACT FROM AUTHOR]

In this work, different dielectric caps were deposited on the GaAs/AlGaAs quantum well (QW) structures followed by rapid thermal annealing to generate different degrees of interdiffusion. Deposition of a layer of Ga[sub x]O[sub y] on top of these dielectric caps resulted in significant suppression of interdiffusion. In these samples, it was found that although the deposition of Ga[sub x]O[sub y] and subsequent annealing caused additional injection of Ga into the SiO[sub 2] layer, Ga atoms were still able to outdiffuse from the GaAs QW structure during annealing, to generate excess Ga vacancies. The suppression of interdiffusion with the presence of Ga vacancies was explained by the thermal stress effect which suppressed Ga vacancy diffusion during annealing. It suggests that Ga[sub x]O[sub y] may therefore be used as a mask material in conjunction with other dielectric capping layers in order to control and selectively achieve impurity-free vacancy disordering. [ABSTRACT FROM AUTHOR]

We studied the structural behavior and electrical transport properties of epitaxial α-SnO thin films grown on the (1¯012) α-Al[sub 2]O[sub 3] (sapphire) substrate. Hall effect measurements revealed that the epitaxial as-deposited SnO film is a p-type semiconductor. In situ x-ray diffraction studies show that the α-SnO phase is metastable and will transform into SnO[sub 2] with the rutile type structure when annealed at high temperatures in air. The onset of this phase transformation was observed to begin approximately at 300 °C during heating. Shortly thereafter, rutile SnO[sub 2] was observed to coexist with α-SnO and intermediate products such as Sn and Sn[sub 3]O[sub 4]. After being annealed at temperatures above 600 °C, the film then fully transformed into the rutile SnO[sub 2] phase. Our results show that the α-SnO to SnO[sub 2] structural transformation proceeds initially by the localized disproportionate redistribution o! f internal oxygen at low temperature, followed by the transformation of the remaining SnO phase and intermediate phases into SnO[sub 2] via the inward diffusion of external oxygen at higher temperatures. Most of the SnO[sub 2] crystallites nucleate epitaxially on α-SnO with the orientation relationship of (101)[sub SnO[sub 2]]//(001)[sub SnO] and their growth processes are controlled by the (101)[sub SnO[sub 2]]//(001)[sub SnO] interfaces, leading to a (101) texture and a laminar grain shape for SnO[sub 2]. The relationship between the electrical transport properties and the structural evolution of the film has also been investigated. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

This work demonstrates the correlation between the microstructure of nanocrystalline SnO[sub 2] thin films and their electrical transport properties and sensitivities to reducing gases. SnO[sub 2] thin films were deposited on the (1¯012) surface of α-Al[sub 2]O[sub 3] (sapphire) using electron beam evaporation of a pure SnO[sub 2] ceramic source, followed by postdeposition annealing in synthetic air. SnO[sub 2] thin films with randomly oriented nanosized grains were obtained by annealing an amorphous SnO film deposited at room temperature. Films with nanosized SnO[sub 2] laminates were obtained by annealing epitaxial α-SnO films deposited at 600 °C. The laminates are oriented with their (101) planes parallel to the substrate surface and have a high density of coherent twin boundaries. Hall measurements indicate that the electron concentration of the film with laminate grains is much lower than for the film with random grains. It is proposed that the! high density twin boundaries inside the laminates trap conducting electrons and significantly reduce the electron concentration. As a result, the sensitivity to reducing gases of the laminar film is higher than that of the corresponding film with randomly oriented SnO[sub 2] grains. It was also found that the grain size has strong effects on the sensitivity of SnO[sub 2] films. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Focuses on a study that used proton irradiation with subsequent rapid thermal annealing to investigate intermixing of InGaAs/GaAs and InGaAs/AlGaAs quantum wells. Experimental details; Results and discussion; Conclusions.

Study Design: An automatic radiographic labeling algorithm called "LevelCheck" was analyzed as a means of decision support for target localization in spine surgery. The potential clinical utility and scenarios in which LevelCheck is likely to be the most beneficial were assessed in a retrospective clinical data set (398 cases) in terms of expert consensus from a multi-reader study (three spine surgeons).Objective: The aim of this study was to evaluate the potential utility of the LevelCheck algorithm for vertebrae localization.Summary Of Background Data: Three hundred ninety-eight intraoperative radiographs and 178 preoperative computed tomographic (CT) images for patients undergoing spine surgery in cervical, thoracic, lumbar regions.Methods: Vertebral labels annotated in preoperative CT image were overlaid on intraoperative radiographs via 3D-2D registration. Three spine surgeons assessed the radiographs and LevelCheck labeling according to a questionnaire evaluating performance, utility, and suitability to surgical workflow. Geometric accuracy and registration run time were measured for each case.Results: LevelCheck was judged to be helpful in 42.2% of the cases (168/398), to improve confidence in 30.6% of the cases (122/398), and in no case diminished performance (0/398), supporting its potential as an independent check and assistant to decision support in spine surgery. The clinical contexts for which the method was judged most likely to be beneficial included the following scenarios: images with a lack of conspicuous anatomical landmarks; level counting across long spine segments; vertebrae obscured by other anatomy (e.g., shoulders); poor radiographic image quality; and anatomical variations/abnormalities. The method demonstrated 100% geometric accuracy (i.e., overlaid labels within the correct vertebral level in all cases) and did not introduce ambiguity in image interpretation.Conclusion: LevelCheck is a potentially useful means of decision support in vertebral level localization in spine surgery.Level Of Evidence: N/A. [ABSTRACT FROM AUTHOR]

Material flow during friction stir welding of ultra-thin 2024 aluminium alloy plates was investigated by using copper powder as marker material. Based on the visualised experiment and numerical computation of material flow produced in the research, the effect of rotational speed on material flow was revealed. In high rotational speed FSW process, flow distance along welding direction of plastic metal on both sides and transverse flow distance to the weld centre line on the retreating side were shorter; however, a larger flow velocity was shown. The flow velocity of plastic metal decreased with the increasing of distance from the weld centre, while it increased with the increasing of rotational speed under a constant rotational speed/welding speed ratio. Maximum and minimum values of the flow velocity of plastic metal were located at the intersection of triple spiral groove of shoulder and both sides of its outer diameter edge, respectively. [ABSTRACT FROM AUTHOR]

Abstract 0.5 mm thick AA7075-T6 ultra-thin sheets were joined successfully by high rotational speed friction stir welding using a pinless tool. Friction stir welding was performed under a high rotational speed of 6000 rpm, and the travel speed ranged from 300 mm/min to 1200 mm/min. Zero thickness reduction and delamination phenomenon were observed in the nugget zone when the travel speed was 1200 mm/min. In this condition, the dynamic recrystallization occurred in the lower part of the nugget zone is incomplete. The mechanical properties gradually improved with the increasing in the travel speed. All the tensile specimens fractured along the boundary between the thermo-mechanically affected zone and the nugget zone, and the morphology showed a shear fracture mode. The maximum tensile strength of 482 MPa (equivalent to ∼90% of base metal) was obtained at the travel speed of 1200 mm/min, which presented a ductile fracture mode and a large amount of η phase (MgZn 2) precipitates and thick tear ridges were detected on the fracture surfaces. [ABSTRACT FROM AUTHOR]

Intravenous immunoglobulin (IVIG), corticosteroids and therapeutic plasma exchange (TPE) are evidence‐based conventional treatments for chronic inflammatory demyelinating polyneuropathy (CIDP). In many centres, unconventional treatments are frequently used as alternatives. We evaluated the outcome of conventional and unconventional therapies in 31 CIDP patients. Overall response rate with conventional first‐line immunotherapies was 77% (20/26), comparable between IVIG and corticosteroids (80% vs 70%). Use of TPE was limited. Treatment response among typical and atypical CIDP were comparable (76 vs 80%). Non‐responders were patients with progressive form of typical CIDP and DADS. Majority (21/26, 81%) of patients with persistent neurological deficits received maintenance therapy. Two subgroups of patients frequently treated with maintenance immunosuppressants were those with improving or stable disease following first‐line treatment (12, 57%) and those with progressive form of CIDP (2, 10%). Primary indications for immunosuppressant use were corticosteroids‐sparing and additional immunosuppression effects. Nine (64%) patients with improving or stable disease given azathioprine were taken off corticosteroids after a median duration of 14 months (range 12‐108). Two (14%) eventually achieved cure or clinical remission without treatment. Maintenance IVIg was given to 6 (29%) relapsing CIDP patients; none of achieved cure or remission after similar median duration of treatment. Less potent immunosuppressant drugs (azathioprine, mycophenolate mofetil, and methotrexate) were frequently used, with moderate adverse effect profiles. In resource limited setting, unconventional treatments were commonly used among CIDP patients with different clinical course of progression. In most cases, careful risk‐benefit re‐assessment is required to justify its further use. [ABSTRACT FROM AUTHOR]

Describes the results of a magneto-optical study of a class of semiconductor heterostructures in which one of the constituent layers is a diluted magnetic semiconductor. Effects of modifications in the band alignment of the heterostructures; Types of ZnSe-based heterostructures used in the study; Use of a variational calculation to model excitons in the heterostructures.

Summary: Background: The association of human leucocyte antigen (HLA) with a variety of diseases has been described, especially with various autoimmune diseases. However, there are few studies on the association between HLA and pityriasis rosea (PR). Aim: To investigate the relevance of HLA II alleles with the development of PR. Methods: Typing for HLA‐DRB1, HLA‐DQA1 and HLA‐DQB1 typing was performed in 55 patients with PR and 90 healthy controls (HCs), using sequence‐based typing (SBT) and PCR with sequence‐specific primers (PCR‐SSP), respectively. Results: We found that the frequency of HLA‐DQB1*03:03 was significantly higher in the PR compared with the HC group [P = 0.001; relative risk (RR) = 2.24; 95% CI 1.38–3.6], while suggestive evidence for a protective effect of HLA‐DQB1*06:06 was observed in the study cohort (P < 0.02; RR = 0.40; 95% CI 0.17–0.90). Conclusions: The HLA‐DQB1*03:03 allele may be a susceptible factor in patients with PR. In addition, the association of HLA‐DQB1*03:03 with PR suggests participation of immunity in the pathogenesis of PR. [ABSTRACT FROM AUTHOR]

High rotational speed friction stir welding (FSW) was successfully employed to weld 6061-T6 aluminum alloy thin plates. The effect of high rotational speed and fast transverse speed on temperature distribution, microstructure evolution, and tensile properties of friction stir welded 6061-T6 joints was investigated in detail. The high rotational speed with fast transverse speed had a significant influence on the peak temperature in the nugget zone (NZ). Increasing the rotational speed and decreasing the transverse speed could obviously improve the peak temperature in the NZ, but exhibit little effect on the heat-affected zone under high rotational speed FSW. The NZ was characterized as a significant refinement of the equiaxed grain. The number of precipitates, subgrains, and low angle grain boundaries in the NZ of high rotational speed FSW joint increased significantly due to moderate heat input and strain rate. The weld zone was seriously softened at low rotational speed, whereas it was alleviated at high rotational speed and was affected slightly by rotational speed and transverse speed. The excellent mechanical properties of the friction stir welded 6061-T6 joints were obtained at a combination of high rotational speed and fast transverse speed. The maximum tensile strength reached 301.8 MPa, 85.8% of the base material. [ABSTRACT FROM AUTHOR]

We searched for the γ-ray signal from M33, one of the largest galaxies in the Local Group, using the Pass8 data from the Fermi Large Area Telescope (LAT). No statistically significant γ-ray emission has been detected in the direction of M33, and we report a new upper limit of the high-energy (>100 MeV) photon flux of 2.3 × 10-9 ph cm-2 s-1, which is stricter than previous constraints and implies a cosmic ray density for M33 that is lower than that suggested previously. The current limit is still, however, in agreement with the correlation of star formation rate and γ-ray luminosity inferred from the Local group galaxies and a few nearby starburst galaxies. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to examine the effects of an alertness-maintaining task (AMT) in older, fatigued drivers.Background: Fatigue during driving increases crash risk, and previous research suggests that alertness and driving in younger adults may be improved using a secondary AMT during boring, fatigue-eliciting drives. However, the potential impact of an AMT on driving has not been investigated in older drivers whose ability to complete dual tasks has been shown to decline and therefore may be negatively affected with an AMT in driving.Method: Younger ( n = 29) and older drivers ( n = 39) participated in a 50-minute simulated drive designed to induce fatigue, followed by four 10-minute sessions alternating between driving with and without an AMT.Results: Younger drivers were significantly more affected by fatigue on driving performance than were older drivers but benefitted significantly from the AMT. Older drivers did not demonstrate increased driver errors with fatigue, and driving did not deteriorate significantly during participation in the AMT condition, although their speed was significantly more variable with the AMT.Conclusion: Consistent with earlier research, an AMT applied during fatiguing driving is effective in improving alertness and reducing driving errors in younger drivers. Importantly, older drivers were relatively unaffected by fatigue, and use of an AMT did not detrimentally affect their driving performance.Application: These results support the potential use of an AMT as a new automotive technology to improve fatigue and promote driver safety, though the benefits of such technology may differ between different age groups. [ABSTRACT FROM AUTHOR]

This article has been retracted. Please see the Retraction Notice for more detail: https://doi.org/10.1134/S0022476623020178 [ABSTRACT FROM AUTHOR]

Introduction:Some studies of Posttraumatic Stress Disorder (PTSD) find executive dysfunction, whereas others do not. We meta-analytically examined the association between executive function and PTSD and used meta-regression to examine the potential moderating effect of PTSD severity on executive function. Methods:We conducted a meta-analysis according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We identified published peer-reviewed articles containing measures of executive function and PTSD symptom severity in subjects with PTSD compared to trauma-unexposed controls or trauma-exposed controls without PTSD, or both. We calculated an effect size for each study containing at least one measure of executive function and PTSD symptom severity. Results:PTSD subjects for whom the Clinician-Administered PTSD Scale (CAPS) score was available had worse executive function compared to both trauma-unexposed controls (g = 0.464,p < .001) and to trauma-exposed controls without PTSD (g = 0.414,p = .001), as did PTSD subjects for whom the Mississippi Scale for Combat-Related PTSD (M-PTSD) score was available (g = 0.390,p < .001). Neither CAPS nor M-PTSD scores significantly moderated the effect size of executive function. Conclusions:PTSD is associated with executive dysfunction, but this association was not moderated by PTSD symptom severity, suggesting that once PTSD occurs, executive dysfunction may occur regardless of PTSD severity. [ABSTRACT FROM PUBLISHER]

In this study, we retrieved a series of 59 dihydroalkylthio-benzyloxopyrimidine (S-DABO) derivatives, which is a class of highly potent HIV-1 non-nucleoside reverse transcriptase inhibitors (NNRTIs) reported from published articles, and analysed them with comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA). Statistically significant three-dimensional quantitative structure–activity relationship (3D-QSAR) models by CoMFA and CoMSIA were derived from a training set of 46 compounds on the basis of the rigid body alignment. Further, the predictive ability of the QSAR models was validated by a test set of 13 compounds. Based on the information derived from CoMFA and CoMSIA contour maps, we have identified some steric and electrostatic features for improving the activities of these inhibitors, and we validated the 3D-QSAR results by a molecular docking method. On the basis of the obtained results, we designed a new series ofS-DABO derivatives with high activities. Therefore, this study could be utilized to design more potentS-DABO analogues as anti-HIV agents. [ABSTRACT FROM PUBLISHER]

Janus-activated kinase (JAKs)-signal transducer and activator of transcription 3 (STAT-3) signalling play critical roles in immunoregulation and immunopathology, which involve inflammatory responses and enteritis. JAK phosphorylates STAT-3 in response to stimulation by cytokines or growth factors, and then activates or represses the gene expression. STAT-3 is activated persistently in cancer cells and contributes to the malignant progression of various types of cancer and inflammation. To elucidate the different roles of JAKs in the activation of STAT-3, the lipopolysaccharide-induced primary intestinal epithelial cell (IEC) acute inflammatory model was established. Small interference RNAs (siRNAs) were then employed to attenuate the expression levels of JAKs. Real-time quantitative reverse transcription-polymerase chain reaction (PCR) (qRT-PCR) revealed that JAK mRNA levels were reduced efficiently by JAK-specific siRNAs. Under the IEC inflammatory model transfected with si-JAK, which equates to effective silencing, qRT-PCR and Western blot assays, suggested that knockdowns of JAK attenuated the JAK-induced down-regulation of STAT-3 at the mRNA or protein levels. In particular, JAK1 played a key role, which was consistent with the RNA-Seq results. Subsequently, the expression levels of proinflammatory cytokines interleukin (IL)-1β and tumour necrosis factor (TNF)-α were down-regulated in the IEC inflammatory model transfected with si-JAK1. JAK1 appears as a direct activator for STAT-3, whereas treatments targeting JAK1 repressed STAT-3 sufficiently pathways in the IEC inflammatory model. Therefore, the control of JAK1 using siRNAs has the potential to be an effective strategy against enteritis. [ABSTRACT FROM AUTHOR]

Focuses on a gallium-arsenide/aluminum arsenide (AlAs) multiple quantum well structure doped n-type in the AlAs barriers. Application of photoluminescence and Raman scattering; Summary of the magnetoluminescence results; Cause of the reduction of the energy gap.

Presents a study which developed an atmospheric pressure metal organic chemical vapor deposition (MOCVD) technique to prepare Bi[sub4]Ti[sub3]O[sub12] ferroelectric thin films. Description of the MOCVD system; Method used in examining the crystal structure of the films; Measurement of the electrical properties.

Examines the growth of spin superlattice structures in which spin-up and spin-down carriers occupy alternating layers in the structure. Determination of the macroscopic properties of any semiconductor heterostructure; Measurements of electron and hole spin lifetimes and spin relaxation processes; Reason for the occurrence of the spin splitting in the valence band.

Comments on a study about the thermoelectric properties of pressure-sintered Si[sub0.8]Ge[sub0.2] thermoelectric alloys. Benefit offered by the thermoelectric generators employed in the U.S. SP-100 project; Goodness factor of a material for thermoelectric application; Inconsistencies of the findings of the study.

In this study, petrochemical secondary effluent was treated by a 55 cm diameter pilot-scale biological aerated filter (BAF) with a media depth of 220 cm. Volcanic rock grains were filled as the BAF media. Median removal efficiency of chemical oxygen demand (COD) and ammonia nitrogen (NH3-N) was 29.35 and 57.98%, respectively. Moreover, the removal profile of the COD, NH3-N, total nitrogen and total organic carbon demonstrated that the filter height of 140 cm made up to 90% of the total removal efficiency of the final effluent. By gas chromatography-mass spectrometry, removal efficiencies of 2-chloromethyl-1,3-dioxolane, and benzonitrile, indene and naphthalene were obtained, ranging from 30.12 to 63.01%. The biomass and microbial activity of the microorganisms on the filter media were in general reduced with increasing filter height, which is consistent with the removal profile of the contaminants. The detected genera Defluviicoccus, Betaproteobacteria_unclassified and the Blastocatella constituted 1.86-6.75% of the identified gene, enhancing the COD and nitrogen removal in BAF for treating petrochemical secondary effluent. [ABSTRACT FROM AUTHOR]

We have developed an original experimental setup, coupling tribology, and velocimetry experiments together with a direct visualization of the contact. The significant interest of the setup is to measure simultaneously the apparent friction coefficient and the velocity of confined layers down to molecular scale. The major challenge of this experimental coupling is to catch information on a nanometer-thick sheared zone confined between a rigid spherical indenter of millimetric radius sliding on a flat surface at constant speed. In order to demonstrate the accuracy of this setup to investigate nanometer-scale sliding layers, we studied a model lipid monolayer deposited on glass slides. It shows that our experimental setup will, therefore, help to highlight the hydrodynamic of such sheared confined layers in lubrication, biolubrication, or friction on solid polymer. [ABSTRACT FROM AUTHOR]

Purpose: Trend-based analyses examining rates of visual field (VF) loss in glaucoma are useful for predicting risk of vision-related morbidity. Although patients with faster losses are likely to require treatment escalation, little is known about rates that might trigger a decision to intervene surgically. The aims of this study were to investigate prior rates of VF loss in patients attending for trabeculectomy and to estimate, in the absence of surgical intervention, lifetime risk of visual impairment, and blindness.Patients and Methods: A retrospective analysis of 117 eyes of 86 consecutive patients with glaucoma attending for trabeculectomy, including 53 patients referred from general ophthalmology clinics and 33 patients from specialist glaucoma clinics. Rates of change in standard automated perimetry mean deviation were examined using linear regression and random coefficient models. Risk of lifetime visual impairment and blindness was calculated using life expectancy data.Results: Mean age at surgery was 71.0±9.7 years. Patients were followed for 10.7±7.5 years prior to surgery with an average of seven useable fields per eye. On average patients referred from general clinics lost 1.04 dB/year compared with 0.77 dB/year in those referred from glaucoma clinics (P=0.070). Patients referred from general clinics had more medication changes prior to surgery (3.4 and 2.6 changes, respectively; P=0.004). Given Scottish life expectancy data, untreated, 61 eyes (52%) would have passed the threshold for visual impairment, whereas 40 (34%) would have passed the threshold demarcating blindness.Conclusion: Patients attending for trabeculectomy had faster average rates of field loss prior to surgery than published values for the general glaucoma population with over one-third of eyes studied predicted to have become blind without intervention. Those managed by glaucoma specialists had fewer changes in medication and tended to slower rates of VF loss, although the latter did not reach statistical significance. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to investigate the potential neuroprotective effect of neuroserpin (NSP) on acute retinal ischemic/reperfusion-induced (IR) injury. An IR injury model was established by elevating intraocular pressure (IOP) for 60 minutes in wild type and tPA-deficient (tPA-/-) mice. Prior to IR injury, 1 μL of 20 μmol/L NSP or an equal volume of bovine serum albumin (BSA) was intravitreally administered. Retinal function was evaluated by electroretinograph (ERG) and the number of apoptotic neurons was determined via TUNEL labeling. Caspase-3, -8, -9,poly (ADP-ribose) polymerase (PARP)and their cleaved forms were subsequently analyzed. It was found that IR injury significantly damaged retinal function, inducing apoptosis in the retina, while NSP attenuated the loss of retinal function and significantly reduced the number of apoptotic neurons in both wild type and tPA-/- mice. The levels of cleaved caspase-3, cleaved PARP (the substrate of caspase-3) and caspase-9 (the modulator of the caspase-3), which had increased following IR injury, were significantly inhibited by NSP in both wild type and tPA-/- mice. NSP increased ischemic tolerance in the retina at least partially by inhibiting the intrinsic cell death signaling pathway of caspase-3. It was therefore concluded that the protective effect of neuroserpin maybe independent from its canonical interaction with a tissue-type plasminogen activator. [ABSTRACT FROM AUTHOR]

Background context A persistent challenge in spine surgery is improving screw fixation in patients with poor bone quality. Augmenting pedicle screw fixation with cement appears to be a promising approach. Purpose The purpose of this study was to survey the literature and assess the previous biomechanical studies on pedicle screw augmentation with cement to provide in-depth discussions of the biomechanical benefits of multiple parameters in screw augmentation. Study design/Setting This is a systematic literature review. Methods A search of Medline was performed, combining search terms of pedicle screw, augmentation, vertebroplasty, kyphoplasty, polymethylmethacrylate, calcium phosphate, or calcium sulfate. The retrieved articles and their references were reviewed, and articles dealing with biomechanical testing were included in this article. Results Polymethylmethacrylate is an effective material for enhancing pedicle screw fixation in both osteoporosis and revision spine surgery models. Several other calcium ceramics also appear promising, although further work is needed in material development. Although fenestrated screw delivery appears to have some benefits, it results in similar screw fixation to prefilling the cement with a solid screw. Some differences in screw biomechanics were noted with varying cement volume and curing time, and some benefits from a kyphoplasty approach over a vertebroplasty approach have been noted. Additionally, in cadaveric models, cemented-augmented screws were able to be removed, albeit at higher extraction torques, without catastrophic damage to the vertebral body. However, there is a risk of cement extravasation leading to potentially neurological or cardiovascular complications with cement use. A major limitation of these reviewed studies is that biomechanical tests were generally performed at screw implantation or after a limited cyclic loading cycle; thus, the results may not be entirely clinically applicable. This is particularly true in the case of the bioactive calcium ceramics, as these biomechanical studies would not have measured the effects of osseointegration. Conclusions Polymethylmethacrylate and various calcium ceramics appear promising for the augmentation of pedicle screw fixation biomechanically in both osteoporosis and revision spine surgery models. Further translational studies should be performed, and the results summarized in this review will need to be correlated with the clinical outcomes. [ABSTRACT FROM AUTHOR]

Fine-grained AISI 4140 steel with ultra-high strength and substantial ductility are obtained by combining warming rolling (WR) and cyclic quenching (CQ). The prior austenite grain size of WR+CQ processed steel is about 5·5 μm, as compared to 12·4 μm for the direct quenching (DQ) processed steel. The microhardness of DQ processed steel and WR+CQ processed steel are similar and fluctuate around HV 610 even further cycles of CQ process are given. The yield strength (YS), ultimate tensile strength (UTS) and percentage elongation after fracture (EL) of WR+one-cycle-CQ are 1943 MPa, 2286 MPa and 8·47%, respectively, indicating the potential of WR+CQ process to produce ultra-high strength steel with WR+CQ is an effective way to develop ultra-high strength steels with substantial ductility. [ABSTRACT FROM AUTHOR]

Study Design. A 3-dimensional-2-dimensional (3D-2D) image registration algorithm, "Level Check," was used to automatically label vertebrae in intraoperative mobile radiographs obtained during spine surgery. Accuracy, computation time, and potential failure modes were evaluated in a retrospective study of 20 patients. Objective. To measure the performance of the Level Check algorithm using clinical images acquired during spine surgery. Summary of Background Data. In spine surgery, the potential for wrong level surgery is significant due to the difficulty of localizing target vertebrae based solely on visual impression, palpation, and fluoroscopy. To remedy this difficulty and reduce the risk of wrong level surgery, our team introduced a program (dubbed Level Check) to automatically localize target vertebrae in mobile radiographs using robust 3D-2D image registration to preoperative computed tomographic (CT) scan. Methods. Twenty consecutive patients undergoing thoracolumbar spine surgery, for whom both a preoperative CT scan and an intraoperative mobile radiograph were available, were retrospectively analyzed. A board-certified neuroradiologist determined the "true" vertebra levels in each radiograph. Registration of the preoperative CT scan to the intraoperative radiograph was calculated via Level Check, and projection distance errors were analyzed. Five hundred random initializations were performed for each patient, and algorithm settings (viz, the number of robust multistarts, ranging 50-200) were varied to evaluate the trade-off between registration error and computation time. Failure mode analysis was performed by individually analyzing unsuccessful registrations (> 5 mm distance error) observed with 50 multi-starts. Results. At 200 robust multistarts (computation time of ~ 26 s), the registration accuracy was 100% across all 10,000 trials. As the number of multistarts (and computation time) decreased, the registration remained fairly robust, down to 99.3% registration accuracy at 50 multistarts (computation time ~ 7 s). Conclusion. The Level Check algorithm correctly identified target vertebrae in intraoperative mobile radiographs of the thoracolumbar spine, demonstrating acceptable computation time, compatibility with routinely obtained preoperative CT scans, and warranting investigation in prospective studies. [ABSTRACT FROM AUTHOR]

In this study a novel ultraviolet (UV) window material, fluorophosphate glass, was prepared by the melt-quenching method. The laser-induced damage (LID) feature of fluorophosphate glass was measured using laser damage experiments, atomic force microscopy (AFM), and scanning electron microscopy (SEM). The results show that fluorophosphate glass has a high ultraviolet transmittance (88%) at 351.00 nm. And the laser-induced damage threshold (LIDT) of the fluorophosphate glass is almost 7.0 J/cm². which is more than 2 times higher than that of fused silica (3.2 J/cm²) irradiated with a 8 ns and 351.00 nm laser by the same processing method. In addition. AFM and SEM images indicate that the damage is also insensitive to the surface roughness of fluorophosphate glass. [ABSTRACT FROM AUTHOR]

Objectives The aim of this study was to explore mechanisms by which fructus Schisandrae chinensis (Wuweizi) is able to reveal its protective capacity against hepatocyte injury. Materials and methods Identification of candidate small molecular compounds was performed by text-mining, extraction and isolation, reverse-docking, network construction, molecular docking and molecular dynamics ( MD) simulation. In vitro cytological examination and western blotting were used to validate efficacy of selected compounds. Results We analyzed chemical composition of fructus Schisandrae chinensis and constructed protein-protein networks of key targets. Networks of mi RNA-protein were constructed. Molecular docking and MD simulation results supported good interaction between selected compound 11/12 and GBA3/ SHBG. Further in vitro examination divulged molecular mechanisms involved. Conclusions In silico analysis and experimental validation together demonstrated that compound 11/12 of fructus Schisandrae chinensis targetted GBA3/ SHBG in hepatocytes. Hopefully this will shed light on exploration of its complex molecular mechanisms. [ABSTRACT FROM AUTHOR]

In this paper, we report the first time preparation of SnO2 nanoparticles (NPs) using a green chemistry method. The leaf extract of Plectranthus amboinicus was used as reducing and stabilization agent for synthesizing SnO2 NPs. The synthesized SnO2 NPs were characterized by SEM, EDX, XRD and UV-vis spectroscopy. Results showed that the biosynthesized SnO2 NPs owing a high purity. The photocatalytic property of the biosynthesized SnO2 NPs was investigated by photodegradation of rhodamine B (Rh B) under visible light illumination. Results indicated that the photocatalytic performance of the biosynthesized SnO2 NPs is much higher than that of commercial SnO2. Moreover, the biosynthesized SnO2 also exhibited an excellent reusability. [ABSTRACT FROM AUTHOR]

In this work, Ag-AgCl/ZnO hybrid was synthesized via a facial wet chemical method. The synthesized hybrid was characterized by SEM, XRD, EDX, UV-vis spectroscopy and photoluminescence spectroscopy. The Ag-AgCl/ZnO hybrid exhibited a significant enhancement of photocatalytic activity towards degradation of methylene blue under visible light. The cause of the enhanced photocatalytic performance could ascribe to the highly facilitated electron transport by the synergistic effect between ZnO and Ag-AgCl. Meanwhile, Ag-AgCl can implement the photosensitization of ZnO with high efficiency through SPR effect. [ABSTRACT FROM AUTHOR]

The Majorana's stellar representation, which represents the evolution of a quantum state with the trajectories of the Majorana stars on a Bloch sphere, provides an intuitive way to study a physical system with a high dimensional projective Hilbert space. In this Letter, we study the Berry phase by these stars and their loops on the Bloch sphere. It is shown that the Berry phase of a general spin state can be expressed by an elegant formula with the solid angles of Majorana star loops. Furthermore, these results can be used to a general state with arbitrary dimensions. To demonstrate our theory, we study a two mode interacting boson system. Finally, the relation between stars' correlations and quantum entanglement is discussed. [ABSTRACT FROM AUTHOR]