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Background: There are no recommendations regarding endovascular treatment (EVT) for patients with acute ischemic stroke (AIS) due to primary medium vessel occlusion (MeVO). The aim of this study was to examine the willingness to perform EVT among stroke physicians in patients with mild, yet personally-disabling deficits due to MeVO. Methods: In an international survey consisting of 4 cases of primary MeVOs, participants were asked whether the presence of personally-disabling deficits would influence their decision-making for EVT despite the patients having low NIHSS scores. Decision rates were calculated based on physician characteristics. Clustered univariable logistic regression was performed. Results: 366 participants from 44 countries provided 2562 answers. 56.9% opted to perform EVT in scenarios in which the deficit was relevant to the patient’s profession versus 41.0% in which no information regarding patient profession was provided (RR1.39, p<0.001). The largest effect sizes were seen for female participants (RR1.68, 95%CI:1.35-2.09), participants >60 years (RR1.61, 95%CI:1.23-2.10), with more neurointervention experience (RR1.60, 95%CI:1.24-2.06), and who personally performed >100 EVTs per year (RR1.63, 95%CI:1.22-2.17). Conclusions: The presence of a patient-relevant deficit in low NIHSS AIS due to MeVO is an important factor for EVT decision-making. This may have relevance for the conduct and interpretation of low NIHSS EVT randomized trials.
Background: Thrombus embolization during endovascular treatment (EVT) occurs in up to 9% of cases, making secondary medium-vessel occlusions (MeVOs) of particular interest to neurointerventionalists. We sought to gain insight into the current EVT approaches for secondary MeVO stroke in an international case-based survey as there are currently no clear recommendations for EVT in these patients. Methods: Participants were presented with three secondary MeVO cases, each consisting of three case-vignettes with changes in patient neurological status (improvement, no change, unable to assess). Clustered multivariable logistic regression analyses were used to assess factors influencing the decision to treat. Results: 366 physicians from 44 countries took part. The majority (54.1%) were in favor of EVT. Participants were more likely to treat occlusions in the anterior M2/3 (74.3%; risk ratio [RR]2.62, 95%CI:2.27-3.03) or A3 (59.7%; RR2.11, 95%CI:1.83-2.42) segment, compared to the M3/4 segment (28.3%;reference). Physicians were less likely to pursue EVT in patients with neurological improvement (49.9% versus 57.0%; RR0.88, 95%CI:0.83-0.92). Interventionalists and more experienced physicians were more likely to treat secondary MeVOs. Conclusions: Physician’s willingness to treat secondary MeVOs endovascularly is limited and varies per occlusion location and change in neurological status. More evidence on the safety and efficacy of EVT for secondary MeVO stroke is needed.
The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.
It is thought that protoplanets formed in protoplanetary disks excite the orbital motion of the surrounding planetesimals, and the bow shocks caused by the highly excited planetesimals heat their icy component evaporating into gas. We have performed model calculations to study the evolution of molecular abundances of the evaporated icy component, which suggests sulfur-bearing molecules can be good tracers of icy planetesimal evaporation. Here we report the result of our ALMA observations of sulfur-bearing molecules towards protoplanetary disks. The lines were undetected but the obtained upper limits of the line fluxes and our model calculations give upper limits of the fractional abundances of x(H2S) < 10−11 and x(SO) < 10−10 in the outer disk. These results are consistent with the molecular abundances in comets in our Solar system.
We report on the formation of shallow junctions with high activation in both n+/p and p+/n Ge junctions using ion implantation and Flash Lamp Annealing (FLA). The shallowest junction depths (Xj) formed for the n+/p and p+/n junctions were 7.6 nm and 6.1 nm with sheet resistances (Rs) of 860 ohms/sq. and 704 ohms/sq., respectively. By reducing knocked-on oxygen during ion implantation in the n+/p junctions, Rs was decreased by between 5% and 15%. The lowest Rs observed was 235 ohms/sq. with a junction depth of 21.5 nm. Hall measurements clearly revealed that knocked-on oxygen degraded phosphorus activation (carrier concentration). In the p+/n Ge junctions, we show that ion implantation damage induced high boron activation. Using this technique, Rs can be reduced from 475 ohms/sq. to 349 ohms/sq. These results indicate that the potential for forming ultra-shallow n+/p and p+/n junctions in the nanometer range in Ge devices using FLA is very high, leading to realistic monolithically-integrated Ge CMOS devices that can take us beyond Si technology.
We present constraints on the variability and binarity of young stars in the central 10 arcseconds (~ 0.4 pc) of the Milky Way Galactic Center (GC) using Keck Adaptive Optics data over a 12 year baseline. Given our experiment’s photometric uncertainties, at least 36% of our sample’s known early-type stars are variable. We identified eclipsing binary systems by searching for periodic variability. In our sample of spectroscopically confirmed and likely early-type stars, we detected the two previously discovered GC eclipsing binary systems. We derived the likely binary fraction of main sequence, early-type stars at the GC via Monte Carlo simulations of eclipsing binary systems, and find that it is at least 32% with 90% confidence.
The effects of charged dust on the steepening of the fields in nonlinear Alfvén waves in astrophysical weakly ionised plasmas are investigated. It is found that the formation of current singularities in the wave due to nonlinear ambipolar diffusion is strongly modified by the effects of the dust. The basic modes for propagation along the magnetic field in a dusty plasma are highly dispersive and split by the anisotropy of the magnetic field into two modes that are oppositely circularly polarised rather than linearly polarised. The right hand circularly polarised wave experiences a cutoff due to the presence of the dust. We derive nonlinear fluid equations describing the dusty plasma, and make approximations for strong coupling of the dust to the neutrals, and for stationary dust. Numerical solution of the equations shows that a nonlinear wave with sharp current features due to ambipolar diffusion involves a rotation of the wave magnetic field about the direction of propagation, and an oscillation of the field components, due to the mode splitting effects of the dust. This is in contrast to the dust-free case, where the sharp reversal of the transverse magnetic field component occurs in a single plane.
We present the initial results of a spectral line survey of L1157 B1 with the Nobeyama 45 m telescope. So far, we have covered the frequencey range of 13.7 GHz (82.0–94.5 GHz and 96.3–97.5 GHz), and have detected 22 species including CH3CHO, HCOOH, HCOOCH3, HNCO, NH2CHO, CH3CN, and CCS. We have also detected the line of CH2DOH. These results demonstrate rich chemistry in this shocked region, which would mainly originate from evaporation of ice mantles by means of shocks.
We have found low-mass star-forming regions with extremely high abundances of carbon-chain molecules. Those are L1527 in Taurus and IRAS 15398-3359 in Lupus. In these sources, carbon-chain molecules would be regenerated in a lukewarm region near the protostar, triggered by the evaporation of the CH4 ice. This is new carbon-chain chemistry (Warm Carbon-Chain Chemistry: WCCC) in contrast to the conventional one applied to cold starless cores. Our interferometric observation shows a steep abundance increase of the carbon-chain molecules inward of a radius of 500 − 1000 AU from the protostar. This size corresponds to the temperature range of 20–30 K, which is close to the evaporation temperature of CH4 (25 K). This result is therefore consistent with the WCCC. The discovery of the WCCC sources demonstrates chemical diversity of low-mass star-forming regions. In particular, a remarkable contrast can be seen between the WCCC and the hot corino chemistry known in IRAS 16293-2422. A possible origin for the diversity would be the time scale of the starless-core phase; a shorter contraction time would result in the WCCC. Relatively low deuterium fractionation ratios in L1527 also support this scenario. If so, chemical compositions will tell us an important clue to understand the source-to-source variation of star-formation processes.
An experimental study on the adhesion of thin films was conducted for the ultraviolet (UV)-cured SiOC films on Si substrate by examining the mechanical energy balance during the indentation process combined with atomic force microscopy observation. The effect of UV cure on the interfacial delamination toughness and the structure of the SiOC films are discussed. The energy release rate of the SiOC film/Si substrate interfacial delamination increases with the increases in the time of UV curing, indicating that the indentation method is efficient to examine the adhesion of coating. As the UV curing time increases, the film thickness and the Si–CH3 bond structure decrease, whereas the SiO2 network structure develops and the mechanical properties of the film are improved. Furthermore, the energy release rate of SiOC film/Si interfacial delamination is well correlated in a proportional manner to the Young's modulus of the film.
In instrumented indentation tests for a thin film coating on a substrate (film/substrate composite), it is well known that the substrate-affected contact area estimated through conventional approximations includes significant uncertainties, leading to a crucial difficulty in determining the elastic modulus and the contact hardness. To overcome this difficulty, an instrumented indentation microscope that enables researchers to make an in situ determination of the contact area is applied to an elastoplastic film on substrates having various values of their elastic moduli. Using the indentation microscope, the substrate-affected indentation contact parameters including contact hardness of the film/substrate composites are determined directly as well as quantitatively without any undesirable assumptions and approximations associated with the contact area estimate. The effect of a stiffer substrate on the contact profile of impression is significant, switching the profile from sinking in to piling up during penetration, and resulting in the substrate-affected contact hardness being highly enhanced at deeper penetrations. Through the present experimental study, it is demonstrated how efficient that instrumented indentation microscopy is in determining the substrate-affected elastoplastic contact parameters of film/substrate composite systems.
Field surveys of supraglacial ponds on debris-covered glaciers in the Nepal Himalaya clarify that ice-cliff calving occurs when the fetch exceeds ∼80 m. Thermal undercutting is important for calving processes in glacial lakes, and subaqueous ice melt rates during the melt and freeze seasons are therefore estimated under simple geomorphologic conditions. In particular, we focus on the differences between valley wind-driven water currents in various fetches during the melt season. Our results demonstrate that the subaqueous ice melt rate exceeds the ice-cliff melt rate when the fetch is >20 m and water temperature is 2–4°C. Calculations suggest the onset of calving due to thermal undercutting is controlled by water currents driven by winds at the surface of the lake, which develop with expanding water surface.
We present an overview of recent astrometric results with VERA. Since 2004, we have been conducting astrometry of tens of Galactic maser sources with VERA, and recently obtained trigonometric parallaxes for several sources, with distances ranging from 180 pc to 5.3 kpc. In this paper, we briefly summarize the results for Galactic star-forming regions, including S269, Orion-KL, NGC 1333, ρ-oph, NGC 281 and others.
Conduct disorder (CD) is a relatively common disorder of childhood and adolescence in the USA with substantial associated morbidity, yet little has been published on CD among Asians and Native Hawaiian/Pacific Islanders (NH/PI) in the USA.
We used the National Epidemiological Survey on Alcohol and Related Conditions (NESARC) to examine the prevalence and correlates of retrospectively reported CD within Asians and NH/PI (18 years and older). We also completed logistic regressions to explore factors associated with CD within Asians (n=1093) and, separately, NH/PI (n=139) and to explain racial differences in CD prevalence.
Asians were about a third as likely [odds ratio (OR) 0.4, 95% confidence interval (CI) 0.22–0.58] whereas NH/PI were about two and half times more likely (OR 2.6, 95% CI 1.31–5.06) to have had CD compared with Caucasian respondents. Within Asians and NH/PI, CD was strongly associated with adult antisocial behavior, substance use and affective disorders. Demographic factors, the age that subjects came to the USA, measures of family environment and family history could not explain the observed differences in prevalence of CD for NH/PI relative to Caucasians.
Asian and NH/PI youth with CD represent a subgroup of Asian youth at very high risk for a number of serious psychiatric disorders. Further investigation is needed to explain the high CD prevalence among NH/PI.
An instrumented indentation microscope was constructed and applied to the measurements of the Meyer hardness and the elastic modulus of several engineering materials ranging from ductile metals to brittle ceramics. Because of the in situ optical observation and determination of the indentation contact area that is synchronized to the indentation load versus depth relation, the mechanical properties determined on the indentation microscope are precise and reliable without any undesirable approximations and assumptions required for estimating the contact area. It is also demonstrated that the instrumented indentation microscope is capable of determining in a quantitative manner the in situ contact profiles of impression (sinking-in/piling-up profiles). The present work suggests that the instrumented indentation microscope will be a powerful tool in the science and engineering of indentation contact mechanics.
We fabricated melt-processed (Sm0.33Eu0.33Gd0.33)Ba2Cu3Oy superconductors with fine Gd2BaCuO5 (Gd-211) particles and studied microstructure and magnetic properties as a function of the Gd-211 content and the initial particle size. Microstructure observation by scanning electron microscopy and transmission electron microscopy confirmed the presence of submicron secondary-phase particles and nanometer-sized RE1+xBa2-xCu3Oy (x ≫ 0) clusters. At 77 K, the critical current densities of 107 and 83 kA/cm2 were achieved at 0 T (self-field) and 2.2 T, respectively (superconducting quantum interference device data).
The effect of bait-delivered anthelmintic to reduce the prevalence of Echinococcus multilocularis in wild red foxes was evaluated in Koshimizu, in the eastern part of Hokkaido, Japan. The study area (200 km2) was divided into baited and non-baited sections. The anthelmintic baits were distributed around fox den sites in the baited section every month for 13 months. After 1 year of the anthelmintic bait distribution, the prevalence of E. multilocularis in foxes, evaluated either by the parasite egg examination (from 27.1 to 5.6%) or coproantigen ELISA (from 59.6 to 29.7%), decreased in the baited section contrasting to that in the non-baited section (parasite egg: from 18.8 to 24.2%; ELISA: from 41.9 to 45.8%). The prevalence of E. multilocularis in grey red-backed vole Clethrionomys rufocanus, caught around fox dens, born after bait distribution also decreased and was significantly lower than that in non-baited section. However, within the study periods, the coproantigen-positive rate in fox faeces sporadically increased, while egg-positive rate constantly decreased. Since coproantigen ELISA can detect pre-patent infection, this observation indicates that reinfection pressure in the baited section was still high even after the 13 months of anthelmintic bait distribution. Therefore, the bait distribution longer than our study period is required for the efficient control of E. multilocularis in wild red fox population.
The dielectric and thermal properties of three-layer structured films were studied. The two outer layers were about 1 μm and the thickness of the middle layer was varied. We measured the thickness dependence of the dielectric constant of the three-layer structured films. The dielectric results were evaluated with a simple serial three-capacitance model. Local thermal property of these polymer films were also measured using a micro-tip local thermal analysis method. Local glass transition of the film was compared with the one expected from bulk data.
Microstructure of (Nd, Eu, Gd)Ba2Cu3O7−δ (NEG-123) samples with (Nd, Eu, Gd)2BaCuO5 (NEG-211) particles were observed by transmission electron microscopy. High-resolution electron microscopy observation demonstrated that the density of microstructural defects was small around the NEG-211 secondary phase particles. Furthermore, the 123/211 interfaces were found to be very clean and sharp. Chemical compositional analysis of the submicron secondary phase particles revealed that these fine particles are not composed of NEG-211 but Eu2BaCuO5 (Eu-211) or Gd2BaCuO5 (Gd-211).