The thin‐film structures of chemical sensors based on conventional organic field‐effect transistors (OFETs) can limit the sensitivity of the devices toward chemical vapors, because charge carriers in ...OFETs are usually concentrated within a few molecular layers at the bottom of the organic semiconductor (OSC) film near the dielectric/semiconductor interface. Chemical vapor molecules have to diffuse through the OSC films before they can interact with charge carriers in the OFET conduction channel. It has been demonstrated that OFET ammonia sensors with porous OSC films can be fabricated by a simple vacuum freeze‐drying template method. The resulted devices can have ammonia sensitivity not only much higher than the pristine OFETs with thin‐film structure but also better than any previously reported OFET sensors, to the best of our knowledge. The porous OFETs show a relative sensitivity as high as 340% ppm−1 upon exposure to 10 parts per billion (ppb) NH3. In addition, the devices also exhibit decent selectivity and stability. This general and simple strategy can be applied to a wide range of OFET chemical sensors to improve the device sensitivity.
Organic field‐effect transistor (OFET)‐based chemical sensors with porous film structure are fabricated by a versatile and low‐cost template method. OFET chemical sensors with the porous structure exhibit much higher sensitivity than that of the pristine one. Porous OFETs exhibit obvious and reproducible response to 10 ppb NH3, with a relative sensitivity up to 340% ppm−1. The devices also show decent stability and sensing selectivity.
Brittleness is an important characteristic of rocks, for it has a strong influence on the failure process no matter from perspective of facilitating rock breakage or controlling rock failure when ...rocks are being loaded. Various brittleness criteria have been proposed to describe rock brittleness. In this paper, the existing brittle indices are summarised and then analysed in terms of their applicability to describe rock brittleness. The analysis demonstrates that the widely used strength ratio or product (
σ
c
/
σ
t
,
σ
c
·
σ
t
) of rocks cannot describe rock brittleness properly and that most of the indices neglect the impact of the rock’s stress state on its brittleness. A new evaluation method that includes the degree of brittleness (
B
d
) and brittle failure intensity (
B
f
) is proposed based on the magnitude and velocity of the post-peak stress drop, which can be easily obtained from the conventional uniaxial and triaxial compression tests. The two indices can accurately account for the influence of the confining pressure on brittleness, and the applicability of the new evaluation method is verified by different experiments. The relationship between
B
d
and
B
f
is also discussed.
Purpose
This paper is an exploratory study to investigate possible remedial measures accounting for a relatively favorable prognosis of health sector workers who have experienced physical WPV in ...Zhejiang province, China.
Methods
Following a proportionate stratified sampling strategy, five tertiary hospitals (in the developed capital city of Hangzhou and other prefecture-level cities), eight secondary hospitals (in counties), and thirty-two primary care facilities (16 urban community health centers and 16 rural township health centers) were conveniently selected. Among 4,862 valid respondents out of 6,089 self-conducted questionnaires, 224 health sector workers who have been directly exposed to physical WPV in the past year were included in the present study.
Results
The present study has three major findings: (1) Victims’ satisfaction with the resolution of the physical WPV conflict was directly associated with the favorable prognosis. (2) Taking days off from work after the violence can promote victims’ satisfaction with the resolution of the physical WPV conflict. (3) Knowing that relevant departments investigated the case can promote victims’ satisfaction with the resolution of the physical WPV conflict.
Conclusion
We propose a combined gesture of “offering adequate days off work after physical WPV” and “every physical violence must be investigated” that should be taken by all medical institutions in China. Health sector workers who get involved in physical WPV incidents should prioritize their safety and avoid any behavior that may intensify the conflicts.
The global prevalence of obesity is rising year by year, which has become a public health problem worldwide. In recent years, animal studies and clinical studies have shown that some lactic acid ...bacteria possess an anti-obesity effect. In our previous study, mixed lactobacilli (
KLDS1.0344 and
KLDS1.0386) exhibited anti-obesity effects
by significantly reducing body weight gain, Lee's index and body fat rate; however, its underlying mechanisms of action remain unclear. Therefore, the present study aims to explore the possible mechanisms for the inhibitory effect of mixed lactobacilli on obesity. C57BL/6J mice were randomly divided into three groups including control group (Control), high fat diet group (HFD) and mixed lactobacilli group (MX), and fed daily for eight consecutive weeks. The results showed that mixed lactobacilli supplementation significantly improved blood lipid levels and liver function, and alleviated liver oxidative stress. Moreover, the mixed lactobacilli supplementation significantly inhibited lipid accumulation in the liver and regulated lipid metabolism in epididymal fat pads. Notably, the mixed lactobacilli treatment modulated the gut microbiota, resulting in a significant increase in acetic acid and butyric acid. Additionally, Spearman's correlation analysis found that several specific genera were significantly correlated with obesity-related indicators. These results indicated that the mixed lactobacilli supplementation could manipulate the gut microbiota and its metabolites (acetic acid and butyric acid), resulting in reduced liver lipid accumulation and improved lipid metabolism of adipose tissue, which inhibited obesity.
Although pulsed radiofrequency treatment (PRFT) has been used to treat trigeminal neuralgia (TN) safely, satisfactory improvement is lacking. Recently, much attention has been paid to the PRFT dose ...and intra‐operative parameters. It has been reported that high‐voltage PRFT could significantly reduce discogenic pain. However, there is no study investigating the effects of high‐voltage PRFT on TN. The aim of this prospective, randomized, double‐blinded study was to evaluate the efficacy and safety of high‐voltage PRFT in comparison with standard‐voltage PRFT for idiopathic TN. Sixty severe TN patients were randomly assigned to 2 groups treated with CT‐guided standard‐ or high‐voltage‐pulsed radiofrequency (RF) of Gasserian ganglion, respectively, between January 2012 and July 2012. Numeric Rating Scales (NRS), carbamazepine dose, and side effects were evaluated at day 1, weeks 1 and 2, months 1, 3, and 6, and 1 year postoperative. There were 27 patients in the standard‐voltage group and 26 patients in the high‐voltage group who completed the 1‐year follow‐up study. The effective rates in the standard‐voltage and high‐voltage PRFT groups were 41% and 69%, respectively, at 1, 3, and 6 months postoperative (P = 0.037). The effective rate in the standard‐voltage group decreased to 19% at 1‐year postoperative, while in the high‐voltage group remained at 69% (P = 0.000). No significant side effects were detected in both groups. In conclusion, CT‐guided high‐voltage PRFT is an effective and safe interventional therapeutic choice for idiopathic TN patients.
Rock anisotropies are an important indicator for design and construction of various engineering projects across the world. To investigate the anisotropic characteristics of P-wave velocity, ...mechanical behavior and thermal properties, laboratory tests were performed on slate samples with various foliation orientations with respect to horizontal direction. The results indicate that the uniaxial compression strength (UCS) exhibits a typical U-type trend, the Young's modulus first decreases and then increases, and the variation of Poisson's ratio shows an opposite trend with the variation in Young's modulus. The anisotropy in strength is greater than that in deformation. Three typical failure modes, i.e. splitting across the foliation planes, shearing and sliding along the foliation planes, and axial splitting failure along the foliation planes, were observed. Scanning electron microscope (SEM) was also applied to analyze the microscopic failure mechanisms. It shows that the slate anisotropies are intrinsically attributed to the directional arrangement of mineral compositions observed by polarizing microscope. P-wave velocity and thermal conductivity both increase with increasing foliation angle, but the linear coefficients of thermal expansion show a decreasing trend. A new empirical formula was then proposed for describing the P-wave velocity and thermal parameters with respect to foliation angle of slate. It displays the empirical predictions match the laboratory measurements. The obtained results can better facilitate our understanding of mechanical behavior and thermal properties of anisotropic rocks, which should be considered in underground engineering applications in layered strata.
Lead (Pb) is one of the most relevant heavy metals contaminants which cause oxidative stress and threaten human health. The lung is one of the organs most severely damaged by Pb. In this study, we ...investigated the protective effect of grape seed procyanidin extract (GSPE) on Pb-induced lung injury in rats. We found that GSPE alleviated Pb-induced lung injury by relieving oxidative stress, reducing release of inflammatory factors, and inhibiting apoptosis. Furthermore, GSPE enhanced the antioxidant defense systems by activating the nuclear factor-erythroid-2-related factor (Nrf2) signaling pathway to promote downstream expression of heme oxygenase 1 and NAD(P)H quinone oxidoreductase 1. The subsequent ubiquitin-binding protein p62 (sequestosome 1), a downstream target of Nrf2, formed a positive feedback loop with Nrf2 during oxidative stress responses. GSPE treatment resulted in activation of adenosine monophosphate-activated protein kinase (AMPK), which was highly involved in Nrf2 activation. Overall, our findings demonstrate that theprotective effect of GSPE on Pb-induced lung injury arises from activation of the AMPK/Nrf2/p62 signaling pathway, thus providing a new approach for treatment of Pb intoxication.
Display omitted
•Grape seed procyanidin extract inhibits lead-induced oxidative stress by activating AMPK/Nrf2/p62.•Grape seed procyanidin extract treatment attenuates inflammation and apoptosis induced by lead.•Grape seed procyanidin extract reduces the accumulation of lead in rat lungs.
The stress distribution around constructions in deep rock can be modified by dynamic disturbances, such as earthquakes. For this, we proposed a new loading method applied to granite sample under ...coupled static and dynamic cyclic loading (CSDCL) condition. The variations in P-wave velocity, gas permeability, and mechanical properties of granite before and after CSDCL are revealed. It shows that with increasing axial static stress, the dynamic cyclic loading amplitude and cycle number, P-wave velocity, uniaxial compressive strength (UCS) and elastic modulus decrease, whilst the permeability and Poisson’s ratio increase. It seems that variations in those parameters have a close relation with the exciting frequency. In this case, CSDCL is applied for crack development along the axial direction in the rock samples, and subsequently results in degradation of mechanical properties, delay of P-wave propagation, and increase of the transport paths. The results show that the permeability and Poisson’s ratio are likely to be more sensitive to the CSDCL, in particular under the axial static stress. The empirical relationships of the P-wave velocity with permeability, UCS, and elastic modulus are established for a pragmatic monitoring purpose. From design point of view, we have established the relationships of the disturbance factors to damage variable. Then the correlations of the damage variable to permeability, UCS, and elastic modulus are analyzed. The testing results in this context could facilitate our understanding of rock stability upon excavation subjected to dynamic disturbances.
The characteristics of the raindrop size distribution (DSD) during regional freezing rain (FR) events that occur throughout the phase change (from liquid to solid) are poorly understood due to ...limited observations. We investigate the evolution of microphysical parameters and the key formation mechanisms of regional FR using the DSDs from five disdrometer sites in January 2018 in the Jianghan Plain (JHP) of Central China. FR is identified via the size and velocity distribution measured from a disdrometer, the discrete Fréchet distancemethod, surface temperature, human observations, and sounding data.
With the persistence of precipitation, the emergence of graupel or snowflakes significantly reduces the proportion of FR. The enhancement of this regional FR event is mainly dominated by the increase in the number concentration of raindrops but weakly affected by the diameters. To improve the accuracy of quantitative precipitation estimation for the FR event, a modified second-degree polynomial relation between the shape
μ
and slope
Λ
of gamma DSDs is derived, and a new
Z-R
(radar reflectivity to rain rate) relationship is developed. The mean values of mass-weighted mean diameters (
D
m
) and generalized intercepts (lg
N
w
) in FR are close to the stratiform results in the northern region of China. Both the melting of tiny-rimed graupels and large-dry snowflakes are a response to the formation of this regional FR process in the JHP, dominated by the joint influence of the physical mechanism of warm rain, vapor deposition, and aggregation/riming coupled with the effect of weak convective motion in some periods.
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