Zero-shot stance detection based on cross-domain feature enhancement by contrastive learning

Zero-shot stance detection is challenging because it requires detecting the stance of previously unseen targets in the inference phase. The ability to learn transferable target-invariant features is critical for zero-shot stance detection. In this work, we propose a stance detection approach that can efficiently adapt to unseen targets, the core of which is to capture target-invariant syntactic expression patterns as transferable knowledge. Specifically, we first augment the data by masking the topic words of sentences, and then feed the augmented data to an unsupervised contrastive learning module to capture transferable features. Then, to fit a specific target, we encode the raw texts as target-specific features. Finally, we adopt an attention mechanism, which combines syntactic expression patterns with target-specific features to obtain enhanced features for predicting previously unseen targets. Experiments demonstrate that our model outperforms competitive baselines on four benchmark datasets

Disrupted Cerebellar Connectivity With the Central Executive Network and the Default-Mode Network in Unmedicated Bipolar II Disorder

Objective: Bipolar disorder (BD) is a common psychiatric disease. Although structural and functional abnormalities of the cerebellum in BD patients have been reported by recent neuroimaging studies, the cerebellar-cerebral functional connectivity (FC) has not yet been examined. The present study aims to investigate the FC between the cerebellum and cerebrum, particularly the central executive network (CEN) and the default-mode network (DMN) in bipolar II disorder (BD II).Methods: Ninety-four patients with unmedicated BD II depression and 100 healthy controls (HCs) underwent the resting-state functional magnetic resonance imaging. Seed-based connectivity analyses were performed using cerebellar seeds previously identified as being involved in the CEN (bilateral Crus Ia) and DMN (bilateral Crus Ib).Results: Compared with HCs, BD II depression patients appeared decreased FC in the right Crus Ia-left dorsal lateral prefrontal cortex (dlPFC) and -left anterior cingulate cortex (ACC), the right Crus Ib-left medial prefrontal cortex (mPFC), -left middle temporal gyrus (MTG), and -left inferior temporal gyrus (ITG). No altered FC between the left Crus Ia or Crus Ib and the cerebral regions was found.Conclusions: Patients with BD II depression showed disrupted FC between the cerebellum and the CEN (mainly in the left dlPFC and ACC) and DMN (mainly in the left mPFC and temporal lobe), suggesting the significant role of the cerebellum-CEN and -DMN connectivity in the pathogenesis of BD

Twist morphing of a composite rotor blade using a novel metamaterial

A novel meta-material has been designed and implemented into a rotor blade to enhance aerodynamic efficiency by achieving a passive twist during rotation. The twist is induced by bend-twist coupling exhibited in the meta-material, which is created to possess anisotropic elastic properties at the bulk level. A concept design of a rectangular blade spar is proposed where the metamaterial is used as the core material to induce twist. Using finite element analysis(FEA) we demonstrate how the bend-twist property of the blade spar is governed by cell geometries of the core material. The twist is activated by a lagwise bending moment generated from a movable mass at the blade tip due to off-centre centrifugal forces. The relationship between the twist, mass location and rotational speed has been explored. Moreover, it was found that the bend-twist property achieved by the proposed blade spar is more effective compared to that of an anisotropic thin-walled composite beam

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

The inhibitory effect of agricultural fiscal expenditure on agricultural green total factor productivity

Abstract Sustainable development of agriculture is the basis for achieving social sustainable development. As the basic industry of national economy, green development of agriculture has become an important support for building an environment-friendly society. Agricultural fiscal expenditure is a direct channel for the government to support agriculture and promote agricultural transformation. It is important to analyze the impact of agricultural fiscal expenditure (AFE) on agricultural green total factor productivity (AGTFP) for sustainable agricultural development. Therefore, this paper employs the random effect model and spatial Durbin model to empirically analyze the direct effect and spatial spillover effect of AFE on AGTFP by using the agricultural panel data of 30 provinces in China from 2008 to 2020. Then, by taking the policy proposal as the time node, this paper also conducts a time heterogeneity analysis to measure the impact of policy enactment on AFE and AGTFP. The main conclusions are as follows: (1) AGTFP exists significant positive spatial spillover effect. The "radiation effect" of agricultural green development is significant. (2) AFE can significantly reduce the AGTFP in the local area, that is, 1% increase of AFE in the local area will reduce AGTFP by 0.037%. At present, agriculture is still yield-oriented. The improvement of AFE in the local area will lead to the expansion of local agricultural production and increase pollution emission. (3) AFE has a significant negative spatial spillover effect on AGTFP, that is, for every 1% increase in AFE, the AGTFP will decrease 0.123% in geographically similar areas, while the AGTFP will decrease by 0.116% in economically and geographically similar areas. It is obvious that AFE will promote the optimization of agricultural production conditions in the province, with the "demonstration effect" on the surrounding areas, the enthusiasm of production in the surrounding areas will increase, thus expanding the pollution emission. (4) According to the analysis of different periods, AFE has a negative impact on AGTFP mainly before the reform innovation is proposed in 2015. It indicates that reform policies have a significant impact on agricultural sustainability

Electroacupuncture for Postoperative Urinary Retention: A Systematic Review and Meta-Analysis

Background. This systematic review aimed at summarizing and evaluating the evidence from randomized controlled trials (RCTs) which used electroacupuncture (EA) to treat postoperative urinary retention (PUR). Methods. We searched thirteen databases electronically through April 2018 without language restrictions. We included RCTs of women with PUR; other types of urinary retention or not-RCTs were excluded. Two independent reviewers extracted studies’ characteristics, and disagreements were resolved by consensus. Data were pooled and expressed as standard mean difference (SMD) for continuous outcomes and odds ratio (OR) for dichotomous outcomes, with 95% confidence interval (CI). Results. We found very low to moderate level of evidence that effects of less than or equal to a week were statistically significant: therapeutic effect improved (OR=4.21; 95%CI [3.04, 5.83]; P<0.00001), residual urine volume decreased (SMD=-13.24; 95%CI [-15.70, -10.78]; P<0.00001), bladder capacity increased (SMD=0.56; 95%CI [0.30, 0.83]; P<0.0001), and urinary flow rate improved (SMD=0.91; 95%CI [0.64, 1.18]; P<0.00001). Effect over a week was statistically significant as well. Therapeutic effect improved (OR=8.29; 95%CI [2.91, 24.25]; P<0.0001), residual urine volume decreased (SMD=-1.78; 95%CI [-2.66, -0.89]; P<0.0001), bladder capacity (SMD=0.92; 95%CI [0.61, 1.23]; P<0.00001) and urinary flow rate (SMD=1.69; 95%CI [0.59, 2.79]; P=0.003) increased, and first urination after surgery was earlier (SMD=-0.92; 95%CI [-1.37, -0.46]; P<0.0001), compared with physical exercise, medication, or no treatment. Conclusion. The efficacy and safety of EA on key outcomes in women with PUR are statistically significant, but the level of most evidence was very low or low. More large-scale, long-term RCTs with rigorous methodological quality are needed

Determination of the Parameters of Ground Acoustic-Impedance in Wind Farms

The ground surface near a wind turbine has a significant influence on the sound propagation from the turbine, and it is therefore important to determine the ground impedance, a quantity that characterizes the ground surface acoustically. Outdoor ground parameters required by a multi-parameter model used to calculate the ground acoustic-impedance are typically unknown, which brings inconvenience for the model use. This paper introduces a technique to determine the parameters of ground acoustic-impedance for use in a multi-parameter impedance model (for example, the Attenborough four-parameter model). The technique consists of three steps: first, the data for sound-pressure level measured at a distance from two different heights are collected, and the sound-pressure-level difference is calculated; second, in line with the experimental data and the sound-pressure-level calculation formula, the MATLAB optimization tool is used to find the optimal values of the parameters used in the impedance model; and finally, when the optimization is finished, the acoustic impedance of the ground is obtained by substituting the optimal values into the impedance model. To check the performance of the calculation, the calculated sound-pressure-level difference is compared to the experimental one. Compared with a traditional method, the technique can significantly reduce the calculation error

Potential serum biomarkers and metabonomic profiling of serum in ischemic stroke patients using UPLC/Q-TOF MS/MS

<div><p>Background</p><p>Stroke still has a high incidence with a tremendous public health burden and it is a leading cause of mortality and disability. However, biomarkers for early diagnosis are absent and the metabolic alterations associated with ischemic stroke are not clearly understood. The objectives of this case-control study are to identify serum biomarkers and explore the metabolic alterations of ischemic stroke.</p><p>Methods</p><p>Metabonomic analysis was performed using ultra-performance liquid chromatography quadrupole time-of-flight tandem mass spectrometry and multivariate statistical analysis was employed to study 60 patients with or without ischemic stroke (30 cases and 30 controls).</p><p>Results</p><p>Serum metabolic profiling identified a series of 12 metabolites with significant alterations, and the related metabolic pathways involved glycerophospholipid, sphingolipid, phospholipid, fat acid, acylcarnitine, heme, and purine metabolism. Subsequently, multiple logistic regression analyses of these metabolites showed uric acid, sphinganine and adrenoyl ethanolamide were potential biomarkers of ischemic stroke with an area under the receiver operating characteristic curve of 0.941.</p><p>Conclusions</p><p>These findings provide insights into the early diagnosis and potential pathophysiology of ischemic stroke.</p></div