The de Gennes extrapolation length is a direction dependent measure of the spatial evolution of the pairing gap near the boundary of a superconductor and thus provides a viable means to probe its ...symmetry. It is expected to be infinite and isotropic for plain s-wave pairing, and finite and anisotropic for d-wave. Here, we synthesize single-layer FeSe films on SrTiO
(001) (STO) substrates by molecular beam epitaxy and measure the de Gennes extrapolation length by scanning tunneling microscopy/spectroscopy. We find a 40% reduction of the superconducting gap near specular 110
edges, yielding an extrapolation length of 8.0 nm. However, near specular 010
edges, the extrapolation length is nearly infinite. These findings are consistent with a phase changing pairing with 2-fold symmetry, indicating d-wave superconductivity. This is further supported by the presence of in-gap states near the specular 110
edges, but not the 010
edges. This work provides direct experimental evidence for d-wave superconductivity in single-layer FeSe/STO and demonstrates quasiparticle scattering at boundaries to be a viable phase sensitive probe of pairing symmetry in Fe-based superconductors.
In recent years, much research has been conducted on time series based human activity recognition (HAR) using wearable sensors. Most existing work for HAR is based on the manual labeling. However, ...the complete time serial signals not only contain different types of activities, but also include many transition and atypical ones. Thus, effectively filtering out these activities has become a significant problem. In this paper, a novel machine learning based segmentation scheme with a multi-probability threshold is proposed for HAR. Threshold segmentation (TS) and slope-area (SA) approaches are employed according to the characteristics of small fluctuation of static activity signals and typical peaks and troughs of periodic-like ones. In addition, a multi-label weighted probability (MLWP) model is proposed to estimate the probability of each activity. The HAR error can be significantly decreased, as the proposed model can solve the problem that the fixed window usually contains multiple kinds of activities, while the unknown activities can be accurately rejected to reduce their impacts. Compared with other existing schemes, computer simulation reveals that the proposed model maintains high performance using the UCI and PAMAP2 datasets. The average HAR accuracies are able to reach 97.71% and 95.93%, respectively.
Cerebral ischemia induces a robust neuroinflammatory response that is largely mediated by the activation of CNS resident microglia. Activated microglia produce pro-inflammatory molecules to cause ...neuronal damage. Identifying regulators of microglial activation bears great potential in discovering promising candidates for neuroprotection post cerebral ischemia. Previous studies demonstrate abnormal elevation of glutaminase 1 (GLS1) in microglia in chronic CNS disorders including Alzheimer's disease and HIV-associated neurocognitive disorders. Ectopic expression of GLS1 induced microglia polarization into pro-inflammatory phenotype and exosome release
. However, whether GLS1 is involved in neuroinflammation in acute brain injury remains unknown. Here, we observed activation of microglia, elevation of GLS1 expression, and accumulation of pro-inflammatory exosomes in rat brains 72 h post focal cerebral ischemia. Treatment with CB839, a glutaminase inhibitor, reversed ischemia-induced microglial activation, inflammatory response, and exosome release. Furthermore, we found that the application of exosome secretion inhibitor, GW4869, displayed similar anti-inflammatory effects to that of CB839, suggesting GLS1-mediated exosome release may play an important role in the formation of neuroinflammatory microenvironment. Therefore, GLS1 may serve as a key mediator and promising target of neuroinflammatory response in cerebral ischemia.
•Patients with dramatically different symptoms were diagnosed with neurobrucellosis.•The patients were diagnosed using next-generation sequencing (NGS) of the cerebrospinal fluid (CSF).•This is the ...first case series of neurobrucellosis diagnosed with NGS of the CSF.
Brucellosis is the most common zoonotic infection in the world. Brucellosis with nervous system involvement is known as ‘neurobrucellosis’ (NB). The diagnosis of NB is difficult because its clinical manifestations are non-specific and the sensitivity of routine culture tests is low.
Next-generation sequencing (NGS) of cerebrospinal fluid (CSF) was used to detect pathogens in patients with clinically suspected central nervous system (CNS) infections at a tertiary referral center in China between June 1, 2016 and June 1, 2017. The clinical characteristics and NGS results of patients with the diagnosis of NB were reviewed in this study.
Four patients were rapidly diagnosed with NB using NGS of the CSF in patients with clinically suspected CNS infections, although the clinical manifestations varied dramatically between these patients. NGS of the CSF revealed that the sequence reads identified that corresponded to Brucella species ranged from 11 to 104, with genomic coverage ranging from 0.043% to 0.4%. Rapid diagnosis led to prompt treatment with the appropriate antibiotics.
This study demonstrates the power of NGS of the CSF coupled with a bioinformatic pipeline in the diagnosis of NB.
Soil organic carbon (SOC) is a key variable to determine soil functioning, ecosystem services, and global carbon cycles. Spectroscopy, particularly optical hyperspectral reflectance coupled with ...machine learning, can provide rapid, efficient, and cost-effective quantification of SOC. However, how to exploit soil hyperspectral reflectance to predict SOC concentration, and the potential performance of airborne and satellite data for predicting surface SOC at large scales remain relatively underknown. This study utilized a continental-scale soil laboratory spectral library (37,540 full-pedon 350–2500 nm reflectance spectra with SOC concentration of 0–780 g·kg−1 across the US) to thoroughly evaluate seven machine learning algorithms including Partial-Least Squares Regression (PLSR), Random Forest (RF), K-Nearest Neighbors (KNN), Ridge, Artificial Neural Networks (ANN), Convolutional Neural Networks (CNN), and Long Short-Term Memory (LSTM) along with four preprocessed spectra, i.e. original, vector normalization, continuum removal, and first-order derivative, to quantify SOC concentration. Furthermore, by using the coupled soil-vegetation-atmosphere radiative transfer model, we simulated twelve airborne and spaceborne hyper/multi-spectral remote sensing data from surface bare soil laboratory spectra to evaluate their potential for estimating SOC concentration of surface bare soils. Results show that LSTM achieved best predictive performance of quantifying SOC concentration for the whole data sets (R2 = 0.96, RMSE = 30.81 g·kg−1), mineral soils (SOC ≤ 120 g·kg−1, R2 = 0.71, RMSE = 10.60 g·kg−1), and organic soils (SOC > 120 g·kg−1, R2 = 0.78, RMSE = 62.31 g·kg−1). Spectral data preprocessing, particularly the first-order derivative, improved the performance of PLSR, RF, Ridge, KNN, and ANN, but not LSTM or CNN. We found that the SOC models of mineral and organic soils should be distinguished given their distinct spectral signatures. Finally, we identified that the shortwave infrared is vital for airborne and spaceborne hyperspectral sensors to monitor surface SOC. This study highlights the high accuracy of LSTM with hyperspectral/multispectral data to mitigate a certain level of noise (soil moisture <0.4 m3·m−3, green leaf area < 0.3 m2·m−2, plant residue <0.4 m2·m−2) for quantifying surface SOC concentration. Forthcoming satellite hyperspectral missions like Surface Biology and Geology (SBG) have a high potential for future global soil carbon monitoring, while high-resolution satellite multispectral fusion data can be an alternative.
•LSTM and CNN were identified from 7 algorithms for spectra-based SOC predictions.•12 airborne and spaceborne data were simulated by a large soil library to predict SOC.•Impacts of soil moisture, vegetation and plant residues on SOC predictions were assessed.•Spectral SOC concentration models for mineral and organic soils are different.•Satellite hyperspectral and multispectral fusion data have high potential to quantify SOC.
Gaseous nitrous acid (HONO) is a crucial precursor of the hydroxyl (OH) radical, which is a "detergent" in the atmosphere. Nowadays, HONO formation mechanisms at polluted urban areas are ...controversial, which restricts the understanding of atmospheric oxidative capacity and radical cycling. Herein, multiday vertical observation of HONO and NO
was simultaneously performed at three heights at the urban area of Beijing for the first time. The vertical distribution of HONO was often unexpected, and it had the highest HONO concentration at 120 m, followed by those at 8 and 240 m. 0D box model simulations suggest that ground and aerosol surfaces might play similar roles in NO
conversion at 8 m during the whole measurement. NO
conversion on aerosol surfaces was the most important HONO source aloft during haze days. At daytime, a strong missing HONO source unexpectedly existed in the urban aloft, and it was relevant to solar radiation and consumed OH.
Liuzijue is a traditional Qigong exercise that is commonly performed in China. However, the treatment effects of Liuzijue Qigong are controversial. The aim of this systematic review was to evaluate ...the efficacy of Liuzijue Qigong in patients with chronic obstructive pulmonary disease (COPD).
Randomised controlled trials were identified by searching several English and Chinese databases from inception to August 8, 2020. Study selection and data extraction were independently performed by two investigators. Data synthesis and analysis were carried out with Review Manager software 5.2. Quality assessment for each study was based on the modified Jadad scale.
Forty studies with 3137 participants were included. Significant improvements were observed in the following outcomes (mean difference, 95% confidence interval): forced expiratory volume in 1 s (0.17, 0.09–0.25) and its percent predicted normal value (6.04, 3.43–8.65), forced expiratory volume in 1 s to forced volume capacity ratio (6.95, 3.06–10.83), 6-min walking distance (33.06, 23.73–42.38), 30-s sit-to-stand test (2.65, 0.98–4.32), COPD assessment test score (− 2.04, − 2.77 to − 1.30), modified Medical Research Council dyspnea scale (− 0.34, − 0.48 to − 0.20), Medical Research Council dyspnea scale (− 0.37, − 0.57 to − 0.18), Traditional Chinese Medicine syndrome score (− 1.85, − 2.86 to − 0.85), Hamilton Anxiety Scale (− 2.31, − 3.04 to − 1.59), Hamilton Depression Scale (− 2.08, − 2.45 to − 1.71) and St. George’s Respiratory Questionnaire (− 6.94, − 9.20 to − 4.67).
Liuzijue Qigong may be an effective adjuvant therapy for the improvement of lung function, exercise capacity, health status, mental status and quality of life in patients with COPD.
•Forty articles were identified to evaluate the efficacy of Liuzijue Qigong in patients with chronic obstructive pulmonary disease (COPD).•Liuzijue Qigong had positive effects on improving lung function, exercise capacity, health status, mental status, and quality of life in COPD patients.•Liuzijue Qigong may be an effective adjuvant therapy for patients with COPD.
The covalently cross‐linked network gives thermosets superior thermal, mechanical, and electrical properties, which, however, squarely makes the large residual stress that is inevitably induced ...during preparation hardly relieved in the glassy state. In this work, an incredible reduction in residual stress is successfully achieved in bulk thermosets in the glassy state through introducing highly dynamic thiocarbamate bonds by “click” reactions of thiols and isocyanates. Due to the excellent dynamic behaviors of thiocarbamate bonds, local network rearrangement is achieved through thermal stimulation, while the strong 3D cross‐linked network is well maintained. Ultimately, a decrease by 44% in residual stress is detected by simply annealing samples at 30 °C below glass transition temperature (Tg), during which they could well maintain more than 98.4% of the storage modulus. After the annealing, more uniform residual stress distribution is also observed, showing a 32% decline in sample standard deviation. However, the residual stress of epoxy resin, a typical thermoset as a reference, changes little even after annealing at Tg. The results prove it a feasible strategy to reduce residual stress in bulk thermosets in the glassy state by introducing proper dynamic covalent bonds.
It is generally believed that residual stress in thermosets represented by epoxy resin could be hardly relieved in the glassy state. By incorporating dynamic covalent bonds into the polymer matrix, an incredible reduction in residual stress is successfully achieved in glassy polythiourethane by simply annealing, during which excellent properties gifted by the highly cross‐linked networks of thermosets are also remained.
Microglial activation is a key pathogenic process at the onset of Alzheimer's disease (AD). Identifying regulators of microglial activation bears great potential in elucidating causes and mechanisms ...of AD and determining candidates for early intervention. Previous studies demonstrate abnormal elevation of glutaminase C (GAC) in HIV-infected or immune-activated microglia. However, whether GAC elevation causes microglial activation remains unknown. In this study, we found heightened expression levels of GAC in early AD mouse brain tissues compared with those in control littermates. Investigations on an
neuroinflammation model revealed that GAC is increased in primary mouse microglia following pro-inflammatory stimulation. To model GAC elevation we overexpressed GAC by plasmid transfection and observed that GAC-overexpression shift the microglial phenotype to a pro-inflammatory state. Treatment with BPTES, a glutaminase inhibitor, reversed LPS-induced microglial activation and inflammation. Furthermore, we discovered that GAC overexpression in mouse microglia increased exosome release and changed exosome content, which includes specific packaging of pro-inflammatory miRNAs that activate microglia. Together, our results demonstrate a causal effect of GAC elevation on microglial activation and exosome release, both of which promote the establishment of a pro-inflammatory microenvironment. Therefore, GAC may have important relevance to the pathogenesis of AD.
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