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Mycobacterium tuberculosis (M.tb) infects a quarter of the world's population and may progress to active tuberculosis (ATB). There is no gold standard for diagnosing latent tuberculosis infection (LTBI). Some immunodiagnostic tests are recommended to detect LTBI but can not distinguish ATB from LTBI. The breath test is useful for diagnosing ATB compared to healthy subjects but was never studied for LTBI. This proof-of-concept study (Chinese Clinical Trials Registry number: ChiCTR2200058346) was the first to explore a novel, rapid, and simple LTBI detection method via breath test on high-pressure photon ionization time-of-flight mass spectrometry (HPPI-TOFMS). The case group of LTBI subjects (n = 185) and the control group (n = 250), which included ATB subgroup (n = 121) and healthy control (HC) subgroup (n = 129), were enrolled. The LTBI detection model indicated that a breath test via HPPI-TOFMS could distinguish LTBI from the control with a sensitivity of 80.0% (95% CI: 67.6%, 92.4%) and a specificity of 80.8% (95% CI: 71.8%, 89.9%). Nevertheless, further intensive studies with a larger sample size are required for clinical application.

BackgroundCurrent clinical tests for mycobacterial pulmonary diseases (MPD), such as pulmonary tuberculosis (PTB) and non-tuberculous mycobacteria pulmonary diseases (NTM-PD), are inaccurate, time-consuming, sputum-dependent, and/or costly. We aimed to develop a simple, rapid and accurate breath test for screening and differential diagnosis of MPD patients in clinical settings.MethodsExhaled breath samples were collected from 142 PTB, 68 NTM-PD and 9 PTB&NTM-PD patients, 93 patients with other pulmonary diseases (OPD) and 181 healthy controls (HC), and tested using the online high-pressure photon ionisation time-of-flight mass spectrometer (HPPI-TOF-MS). Machine learning models were trained and blindly tested for the detection of MPD, PTB, NTM-PD, and the discrimination between PTB and NTM-PD, respectively. Diagnostic performance was evaluated by metrics of sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve (AUC).ResultsThe breath PTB detection model achieved a sensitivity of 81.8%, a specificity of 94.3%, an accuracy of 90.7%, and an AUC of 0.957 in the blinded test set (n=150). The corresponding metrics for the NTM-PD detection model were 95.5%, 86.7%, 88.0% and 0.947, respectively. For distinguishing PTB from NTM-PD, the model also achieved good performance with sensitivity, specificity, accuracy, and AUC of 95.5%, 90.9%, 93.9% and 0.974, respectively. 24 potential breath biomarkers associated with MPD were putatively identified and discussed, which included 2-picoline, ethanol, 1-Pentene, etc.ConclusionsThe developed breathomics-based MPD detection method was demonstrated for the first time with good performance for potential screening and diagnosis of PTB and NTM-PD using a refined operating procedure on the HPPI-TOF-MS platform.

In order to evaluate the effect of chromium content in carbon steel on the corrosion resistance of carbon steel materials, the corrosion behavior of 1Cr and N80 steels was investigated in this study by immersion weight loss method under three different CO2 partial pressure and temperature conditions in formation water for 72, 168 and 336 h. Detailed material surface morphological characterization was performed by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and confocal laser scanning microscopy (CLSM). The results show that the pitting corrosion of N80 carbon steel is serious at medium temperature and low CO2 partial pressure (50 °C, 0.30 MPa), and the corrosion rate is significantly higher than that of 1Cr steel. However, at high-temperature and high CO2 partial pressure (100 °C/0.63 MPa and 114 °C/0.73 MPa), 1Cr steel is more inclined to the mesa corrosion dominated by local corrosion characteristics, and the corrosion rate is seriously higher than that of N80 steel with uniform corrosion. From the experimental results, we can know the corrosion resistance of carbon steel and 1Cr steel is not only affected by the corrosion environment, but also depends on the formation process of the product film, as well as its compactness and integrity characteristics. At low-temperature and low CO2 partial pressure, 1 wt.% chromium content can provide a certain degree of corrosion resistance, while high temperature and high partial pressure can broaden the application window of carbon steel N80 and weaken the corrosion inhibition effect of chromium.

Purpose: To determine the efficacy of the combination of traditional Chinese medicine (TCM) foot bath and mild moxibustion in the treatment of limb pain in patients with diabetic peripheral neuropathy (DPN). Methods: A total of 120 patients with symptoms of DPN-induced pain who were hospitalized at the Department of Endocrinology in the 903rd Hospital of PLA, from January 2020 to June 2021, were included in this study. They were randomly assigned to a study group and a control group, with 60 patients in each group. Patients in both groups received conventional treatments and nursing care, while those in study group were additionally treated with a combination of TCM foot bath and mild moxibustion. Treatment efficacy in the patients was evaluated using Short-Form McGill Pain Questionnaire (SF-MPQ), pain rating index (PRI), visual analogue scale (VAS), TCM symptom score (TCMSS), and Toronto Clinical Scoring System (TCSS). Results: Compared with control group, there were significant improvements in pain-related scores, namely, SF-MPQ, (p ˂ 0.05); PRI, (p < 0.01); VAS, (p < 0.05); as well as overall efficacy (p < 0.05). Similar improvements were also observed with regard to TCMSS (p < 0.001) and TCSS (p < 0.001) in the study group. However, there were no significant changes in Adjusted Diabetes Quality of Life (A-DQOL) score and blood glucose control in both groups. Conclusion: Relative to the conventional treatment for DPN, limb pain and disease score of patients are significantly reduced by the combination of TCM foot bath and mild moxibustion treatments. Further clinical trials would be required prior to application in clinical practice.

As an important post-translational modification, ubiquitination mediates ∼80% of protein degradation in eukaryotes. The degree of protein ubiquitination is tightly determined by the delicate balance between specific ubiquitin ligase (E3)-mediated ubiquitination and deubiquitinase-mediated deubiquitination. In 2017, we developed UbiBrowser 1.0, which is an integrated database for predicted human proteome-wide E3–substrate interactions. Here, to meet the urgent requirement of proteome-wide E3/deubiquitinase–substrate interactions (ESIs/DSIs) in multiple organisms, we updated UbiBrowser to version 2.0 (http://ubibrowser.ncpsb.org.cn). Using an improved protocol, we collected 4068/967 known ESIs/DSIs by manual curation, and we predicted about 2.2 million highly confident ESIs/DSIs in 39 organisms, with >210-fold increase in total data volume. In addition, we made several new features in the updated version: (i) it allows exploring proteins’ upstream E3 ligases and deubiquitinases simultaneously; (ii) it has significantly increased species coverage; (iii) it presents a uniform confidence scoring system to rank predicted ESIs/DSIs. To facilitate the usage of UbiBrowser 2.0, we also redesigned the web interface for exploring these known and predicted ESIs/DSIs, and added functions of ‘Browse’, ‘Download’ and ‘Application Programming Interface’. We believe that UbiBrowser 2.0, as a discovery tool, will contribute to the study of protein ubiquitination and the development of drug targets for complex diseases.

As the key running part of the railway freight transportation system, the wheel not only bears the load of the vehicle, but also ensures the running and steering of the car body on the rails. The frequent high-speed friction with the rail and brake is the main reason for early failure of wheelset tread. Therefore, real-time status monitoring and early fault diagnosis of wheel treads have become key technical issues that must be solved in the reform of the railway freight maintenance system. In this paper, an adaptive hybrid Simulated Annealing Cuckoo Search algorithm (SA-ACS) is proposed and applied to the Deep Belief Network (DBN). The SA-ACS-DBN algorithm is used to improve the training speed and convergence accuracy of the diagnosis model. Finally, it is found through the comparison experiment of wheel tread fault data that the data results prove the feasibility of the SA-ACS-DBN model in the application of wheelset fault diagnosis.

Remaining Useful Life (RUL) prediction is one of the most common activities to ensure the reliability of a degradation system. In previous RUL prediction schemes based on RNN autoencoder, the multi-dimensional sensor data for each timestep made an equal contribution to the generation of the embedding vector during the encoding process. Besides, the single embedding vector carries the burden of decoding the entire multi-timestep information. To overcome the above shortcomings, two improvements are proposed: (1) For the embedding vectors to highlight critical timestep information, weights are assigned to each timestep information through an attention mechanism. (2) To reduce the decoding burden on a single embedding vector, a skip connection is introduced at each step of the decoding process to improve BiGRU decoding capabilities. The prognostic performance of the proposed method BiGRU-AS is evaluated on two publicly available datasets: the C-MAPSS dataset (simulation dataset) and the milling dataset (experimental dataset). Compared to the latest prediction methods, the experimental results show that the proposed method is competitive in RUL prediction for mechanical systems.

A nanoscale MOF-199 was synthesized in a simple and fast way by mixing btc triethylammonium and copper nitrate solution at room temperature and characterized by scanning electron microscopy, transm...

After a major outbreak of the coronavirus disease (COVID-19) starting in late December 2019, there were no new cases reported in mainland China for the first time on March 18, 2020, and no new cases reported in Hong Kong Special Administrative Region on April 20, 2020. However, these places had reported new cases and experienced a second wave since June 11, 2020. Here we develop a stochastic discrete-time epidemic model to evaluate the risk of COVID-19 resurgence by analyzing the data from the beginning of the outbreak to the second wave in these three places. In the model, we use an input parameter to represent a few potential risks that may cause a second wave, including asymptomatic infection, imported cases from other places, and virus from the environment such as frozen food packages. The effect of physical distancing restrictions imposed at different stages of the outbreak is also included in the model. Model simulations show that the magnitude of the input and the time between the initial entry and subsequent case confirmation significantly affect the probability of the second wave occurrence. Although the susceptible population size does not change the probability of resurgence, it can influence the severity of the outbreak when a second wave occurs. Therefore, to prevent the occurrence of a future wave, timely screening and detection are needed to identify infected cases in the early stage of infection. When infected cases appear, various measures such as contact tracing and quarantine should be followed to reduce the size of susceptible population in order to mitigate the COVID-19 outbreak.

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has caused a tremendous threat to global health. polymerase chain reaction (PCR) and antigen testing have played a prominent role in the detection of SARS-CoV-2-infected individuals and disease control. An efficient, reliable detection tool is still urgently needed to halt the global COVID-19 pandemic. Recently, the food and drug administration (FDA) emergency approved volatile organic component (VOC) as an alternative test for COVID-19 detection. In this case-control study, we prospectively and consecutively recruited 95 confirmed COVID-19 patients and 106 healthy controls in the designated hospital for treatment of COVID-19 patients in Shenzhen, China. Exhaled breath samples were collected and stored in customized bags and then detected by high-pressure photon ionization time-of-flight mass spectrometry for VOCs. Machine learning algorithms were employed for COVID-19 detection model construction. Participants were randomly assigned in a 5:2:3 ratio to the training, validation, and blinded test sets. The sensitivity (SEN), specificity (SPE), and other general metrics were employed for the VOCs based COVID-19 detection model performance evaluation. The VOCs based COVID-19 detection model achieved good performance, with a SEN of 92.2% (95% CI: 83.8%, 95.6%), a SPE of 86.1% (95% CI: 74.8%, 97.4%) on blinded test set. Five potential VOC ions related to COVID-19 infection were discovered, which are significantly different between COVID-19 infected patients and controls. This study evaluated a simple, fast, non-invasive VOCs-based COVID-19 detection method and demonstrated that it has good sensitivity and specificity in distinguishing COVID-19 infected patients from controls. It has great potential for fast and accurate COVID-19 detection.

By assuming a periodic variation in the intrinsic growth rate of the prey, a nonlinear ecological system with periodic forcing and state-dependent feedback control is proposed. The main purpose of the present paper is to study the dynamical behavior generated by periodic forcing and nonlinear impulse perturbations and their effects on pest control. To do this, we first investigate the existence and stability of the boundary periodic solution, and then we employ the numerical bifurcation techniques, mainly including one-dimensional and two-dimensional parameter bifurcation analyses, to reveal that the system exhibits rich and complex dynamic behaviors. Especially, period-adding bifurcation with chaos is found in the two-parameter bifurcation plane. Moreover, we find the periodic structure similar to Arnold tongues, and they are arranged according to the sequence of a Farey tree. In addition, one-dimensional bifurcation diagrams reveal the existence of order-[Formula: see text] periodic, and chaotic solutions, multiple coexisting attractors, period-doubling bifurcations, period-halving bifurcations, and so on. Finally, the effects of the initial population density of pests and natural enemies on the pulse frequency and the biological significance related to the numerical results are studied and discussed.

For the problem that the fixed threshold setting method cannot realize dynamic monitoring of voltage difference fault, a data-driven method is adopted in this paper to establish an adaptive threshold algorithm for voltage difference of the energy storage system by combining the threshold setting for battery voltage difference of the energy storage system with the exponentially weighted moving-average (EWMA) method. Compared with other methods, the alarm threshold obtained by the algorithm can realize dynamic monitoring of the voltage difference in the whole charging and discharging process and improve the accuracy of early warning. The actual operation data of a power grid-side energy storage power station in China show that the false alarm rate and omissive alarm rate of the algorithm are lower than 1%, which can greatly alleviate the workload of operation and maintenance personnel while ensuring the safe and reliable operation of the system, with good application and promotion value.

Soft pneumatic robots have gained research interests in many fields, showing an advantage of compliance and safeness to human-robotic interaction and various environments. In this paper, a multi/dual-chamber soft crawling robot based on unbalanced pneumatic actuation is presented, which requires only simple design and control to realize the forward locomotion and steering. The design is composed of three parts: the main part of the crawling robot is made of hyper-elastic silicone rubber; an unstretchable fabric is attached outside of part of the robot to form an exterior constraint; two chambers are mounted on the head as steering module. Experiments validate the design in principle and an adequate locomotion performance of the robot. Due to the simple, low-cost structure and its flexible actuation, such crawling robots can be used to perform pipeline exploration, search and rescue missions.

Karst collapse pillars (KCPs) frequently cause severe groundwater inrush disasters in coal mining above a confined aquifer. An accurate understanding of the damage and fracture evolution, permeability enhancement, and seepage changes in KCPs under the combined action of mining-induced stress and confined hydraulic pressure is of great significance for the early prediction and prevention of groundwater inrush from KCPs in coal seam floors. In this study, a micromechanics-based coupled stress-seepage-damage (SSD) modeling approach, in which the macroscopic mechanical and hydraulic properties of the rock are explicitly related to the microcrack kinetics, is proposed to simulate the fracture evolution and the associated groundwater flow in KCPs. An in situ high-precision microseismic monitoring technology is used to verify the micromechanical modeling results, which indicate that the numerical model successfully reproduces the damage and fracture evolution in a coal seam floor with a KCP during the mining process. The presented model also provides a visual representation of the complex process of KCP activation and groundwater inrush channel formation. A numerical study shows that the damage and activation of a KCP start from the edge of the KCP, gradually develop toward the interior of the KCP, and eventually connect with the damage fracture zone of the floor, forming a primary water-conducting channel in the KCP, causing the confined groundwater to flow into the working face. Groundwater inrush from a KCP is a gradual process instead of a mutation process. A reduction in the distance between the working face and a KCP and increases in the confined hydraulic pressure and the initial water-conducting height of the KCP can significantly increase the risk of groundwater inrush from the KCP.

With the continuous development of railway informatization, railway operation and maintenance system also needs to be more intelligent. Starting from the basic concepts of operation and maintenance, intelligent operation and maintenance and railway intelligent operation and maintenance, according to the current operation and maintenance situation of some systems in the railway industry, this paper studies the overall architecture and workflow of the railway intelligent operation and maintenance system. Intelligent operation and maintenance technology can provide technical means for ensuring railway transportation safety, improving maintenance efficiency and reducing operation and maintenance cost. The implementation of railway intelligent operation and maintenance system will make railway operation and maintenance move forward from traditional decentralized mode to centralized and unified mode, so as to make railway operation and maintenance work more scientific and efficient and improve the overall operation and maintenance level of railway.

The development of a general approach for fabricating stable ultra-small heterogeneous nanocatalysts has been intensively pursued. However, issues related to complex synthesis processes and structural stability have restricted their investigation and application. Here we report a facile organometallic conjunction strategy for the large-scale fabrication of porous carbon framework encapsulated highly dispersed sub-3 nm ultra-small nanoparticles (USMNPs@PCF). This methodology is based on the convenient aldol condensation reaction to manufacture a metallo-supramolecular polymer precursor and then consequent annealing to form the target nanocomposite. This technique was successfully applied to the preparation of varieties of USMNPs@PCF, including Fe, Co, Ni, Mo, Ru, Rh, Pd and Pt. As a representative application, the PCF encapsulated sub-3 nm Pd nanoparticles demonstrated remarkable durability and efficiency for chemoselective hydrogenation of nitroarenes to their corresponding anilines under ambient conditions with low catalyst loading. All hydrogenation reactions can complete in 4 min with >99% conversion and >99% chemoselectivity. The turnover frequency (TOF) was up to 11 400 h−1 for p-nitrophenol. This work provides a general, scalable and economical route for the manufacture of sub-3 nm and highly dispersed nanocomposites, which can be used in many other important fields, such as electrochemistry, energy science and environmental protection.

We present a novel strategy for the scalable fabrication of γ-Fe2O3@3DPCF, a three dimensional porous carbon frameworks anchored ultra uniform and ultra stable nano γ-Fe2O3. The γ-Fe2O3@3DPCF nanocomposites were facilely prepared with the following route: a condensation of iron (III) acetylacetonate with acetoacetone at room temperature formed the polymer precursor (PPr), which was carbonized subsequently at 800 oC. The homogeneous aldol condensation offered an ultra uniform distribution of the iron, so that the γ-Fe2O3 nanoparticles (NPs) were uniformly distributed in the 3D carbon architecture with the average size of approximate 20 nm. The Fe2O3 NPs was capped with carbon, so that the iron oxide maintained its γ-phase instead of the more stable α-phase. The nanocomposite was an exquisite catalyst for the reduction of nitroarene, it gave >99% conversion and 100% selectivity for the reduction of nitroarenes to the corresponding anilines at 100 °C. The fabrication of the γ-Fe2O3@3DPCF nanocatalyst represents a green and scalable method for the synthesis of novel carbon-based metal oxides nanostructure.

To solve the large deformation problem of thin-layered carbonaceous slate in Minxian Tunnel, the mechanical properties and large-deformation mechanism of carbonaceous slate are analyzed. A negative Poisson's ratio (NPR) anchor cable supporting solution was designed based on the principle of energy coupling support and field tests were carried out. Thin-layered low-strength jointed rock mass and extremely high geo-stress is found to be the main causes of large deformation in Minxian Tunnel. Dissolution of clay minerals in carbonaceous slate by fissure water accelerates softening of surrounding rocks, which is another reason for the large deformation. The adopted NPR anchor cable energy supporting system can maintain a constant support reaction force (350 ± 10kN) for the surrounding rock, releasing the deformation energy of the surrounding rock through conical body sliding. Evaluation study on NPR anchor cable support was performed including axial force of NPR anchor cable, convergence deformation of surrounding rock, pressure monitoring between steel arch with surrounding rock and pressure monitoring between primary support structure with secondary lining. Monitoring results demonstrate the effectiveness of the adopted NPR anchor cable (7.3 m and 12.3 m) supporting system in Minxian Tunnel. This report would be helpful for the construction of soft rock tunnel under high geo-stress conditions for the control of large deformation and failure.

Herein a nano-scale bimetallic Fe/Eu-MOF with a regular octahedral structure was synthesized for the first time. The synthesized Fe/Eu-MOF has both peroxidase-like activity and fluorescence properties. Fe/Eu-MOF can catalyze H2O2 to oxidize the chromogenic substrate TMB to produce blue oxTMB, which has ultraviolet absorption at 652 nm. Unexpectedly, the generated oxTMB can effectively quench the fluorescence of the catalyst Fe/Eu-MOF at 450 nm. The quenching mechanism is mainly the internal filtration effect (IFE), accompanied by static quenching (SQE), Forster resonance energy transfer (FRET) and photoelectron transfer (PET). Fe/Eu-MOF has a high affinity for sodium pyrophosphate (PPi). PPi can be adsorbed to the surface of Fe/Eu-MOF, destroying the structure of Fe/Eu-MOF and inhibiting its catalytic activity, resulting in a decrease in UV absorbance and the decline of fluorescence quenching. In contrast, phosphoric acid (Pi) has almost no effect on the reaction system. Alkaline phosphatase (ALP) can catalyze the hydrolysis of PPi to Pi, thereby reducing the inhibitory effect of PPi. Based on this, we successfully constructed a dual-mode ALP sensor with high selectivity. The linear ranges based on the 652 nm absorption or the fluorescence detection are from 1 to 200 U/L, and the detection limits are 0.6 for the absorption method and 0.9 U/L for the fluorescence method, respectively.

The prediction of earthquakes remains challenging. An unconventional idea that earthquakes can be predicted is proposed, based on the mechanics of the double block system (DBS). The central point of the mechanics of DBS lies in the measurement of the forces acting on the surface separating the two blocks, the relation of which should obey Newton’s laws (referred to as Newton’s forces). A Newton’s force monitoring system (NFMS), consisting of in situ measurement, remote sensing and indoor monitoring, has been developed. The key instrument of the NFMS is the constant-resistance and large-deformation (CRLD) bolt incorporated with a negative Poisson’s ratio (NPR) structure, referred to as CRLD bolt or NPR bolt, because of its unconventional performance that makes measurement of the Newton’s forces possible in seismically-active faults. The basic analytical and experimental work on formulating the DBS and NPR cable is outlined. The methods and techniques of the NFMS are presented. The validity of the mechanics of DBS and the applicability of the NRMS were verified by indoor experiments on Wenchuan and Longmen mountain active faults. Among many successful applications of NFMS to forecasting landslides, one field case in Nanfen open pit iron mines is presented; four field cases of the application of NFMS in registering the activities of the seismically active faults are also presented.

A test system was developed for true triaxial hydraulic fracturing (HF) and gas fracturing (GF) combined with acoustic emission (AE) monitoring and 3D computerized tomography (CT) scanning reconstruction to carry out a series of HF and GF tests under different true triaxial loading conditions. The critical breakdown pressure characteristics, the AE activities, and the fracture propagation and spatial morphologies were obtained during the fracturing process. The test results showed that the GF breakdown pressure was approximately 29.0–31.3% less than the HF breakdown pressure. Moreover, for the GF specimen, the gas pore pressure induced a large number of new microfractures before critical fracture. However, both HF and GF under true axial compression can only produce simple main longitudinal fractures (LFs, along the borehole) and transverse fractures (TFs, across the borehole) that are strictly dependent on the initial true triaxial stress field. Based on the experimental observations, a hypothesis for the initiation of the HF and GF under true triaxial compression was proposed by using the maximum tangential stress on the borehole wall and the maximum axial stress along the borehole. Accordingly, analytical solutions of the critical breakdown pressure for the HF (impermeable) and GF (permeable) specimens were derived. The theoretical predictions agree well with the observations from the 3D numerical simulations and tests. Lastly, a novel pulsed GF method (dynamic loading fracturing) was proposed to overcome the dependence of the in-situ crustal stress field associated with traditional HF and GF methods (static loading fracturing). Laboratory test results showed that the dynamic pulsed GF at moderate pressure can generate a complex and random fracture network independent of the in-situ stress field in rock.

Curtain wall structure is the common type of external fixation structure of high-rise and super-high-rise buildings. The application advantages of curtain wall structure have been paid attention to by engineers, so its application is more and more extensive. Based on this, this paper briefly expounds the basic concept of curtain wall, and puts forward the development strategy of management work in building curtain wall construction, aiming at deeply analyzing the current situation of building curtain wall construction in China and deeply exploring the role of management work in building curtain wall construction stage from the project management level.

In this study, a microscale visualization test system for rock fracture grouting was developed to perform in-situ, dynamic, and visual observational studies of the microscopic behaviour of grout particle filtration during grouting. A series of laboratory grouting tests of ordinary cement (OC) grout and microfine cement (MC) grout were carried out under various fracture aperture conditions using this testing system. The curves of the macroscopic grouting pressure and grout weight changes during grouting, as well as visual images of the microscopic filtration of the grout particles, were obtained. For a large fracture aperture, the grouting processes of both the OC and MC grouts can be divided into three stages, namely, the pressurization stage (stage I), the constant pressure stage (stage II), and the depressurization stage (stage III), whereas the grouting processes under the medium and small fracture aperture conditions consisted of only stages I and II. Almost no filtration of either the OC or MC grouts occurred at the fracture inlet under the large fracture aperture condition. By contrast, under the medium and small fracture aperture conditions, the OC and MC grout particles began to accumulate at the fracture inlet in the pressurization stage (stage I), rapidly forming a semi-circular arch-shaped filter cake and increasing in thickness. The filter cake formed by the OC grout was more stable than that formed by the MC grout. Quantitative measurement and analysis of the microscopic images of the grout particle filtration showed that the thicknesses of the filter cakes formed by the OC and MC grouts increased rapidly with time, and with an increase in the fracture aperture, the filter cakes formed by both grout types initiated later, and the rate of increase in the filter cake thickness gradually decreased. Finally, a new method for evaluating the penetrability and filtration characteristics (i.e., bmin and bcrit values) of grout based on microscopic images of grout particle filtration was proposed.

Fabrication of anilines from the corresponding nitroaromatics is a hot topic both for academia and for industry; however, conducting this protocol in water over a noble-metal-free catalytic system is still a great challenge. Continuous efforts are being made on exploiting novel catalysts for this transformation. In this work, we developed a scalable method for synthesizing the uniform flowerlike amorphous α-FeOOH hierarchical supraparticles. The well-defined amorphous α-FeOOH was prepared through an environmentally benign method, which is hydrolysis of the self-assembled iron glycolate at room temperature. Compared with other iron-only catalysts, this flowerlike amorphous α-FeOOH hierarchical supraparticle catalyst exhibits the best performance in the catalytic reduction of nitroaromatics to corresponding anilines by using water as the reaction solvent (turn over frequency is 106 h–1 for 4-nitrophenol in water). The further results indicated that the amorphous structure, special nanostructures, and adsorp...

Immunosuppression is body’s state in which the activation or efficacy of immune system is weakened. It is associated with a wide spectrum of human diseases. In the last two decades, tremendous efforts have been made to elucidate the mechanism of hundreds of immunosuppression genes. Immunosuppression genes could be valuable drug targets or biomarkers for the immunotherapeutic treatment of different diseases. However, the information of all previously identified immunosuppression genes is dispersed in thousands of publications. Here, we provide the HisgAtlas database that collects 995 previously identified human immunosuppression genes using text mining and manual curation. We believe HisgAtlas will be a valuable resource to search human immunosuppression genes as well as to investigate their functions in further research. Database URL: http://biokb.ncpsb.org/HisgAtlas/

Renewable energy is playing more and more important roles nowadays in the world and hydrogen is considered as one of them with high availability, and being clean. This paper firstly begins with the utilization and development of hydrogen as energy, explains the significance of underground hydrogen storage and conventional storage methods, summarizes the underground gas storage experience of all countries, and concludes the general patterns of underground gas storage, for example, depleted reservoirs, aquifers, salt caverns and excavated caverns. After that by comparing the physical and chemical properties of hydrogen and methane, the feasibility of underground hydrogen storage has been analyzed in depth and the potential barriers, such as high permeability, chemical reaction, extraction purity, are summarized. Finally the development prospects of hydrogen underground storage in China are summed up in the perspectives of energy restructure, policy support, and technology development.

We present a novel strategy for the scalable fabrication of γ-Fe

This study was committed to the simulation of a roadway excavation in the geologically horizontal strata at great depth based on physical modeling test. A new approach of Physically Finite Elemental Slab Assemblage (PFESA) was employed for construction of the large-scale physical model simulating roadway excavation in stratified rocks. The roadway excavation without support in our test was designed as two phases, i.e. phase 1: full-face excavation and phase 2: staged excavation. The experimental test was carried out under the deep ground stress condition of unbalanced confinement. Rock response to the excavation was monitored and captured in real-time and over the entire field by using infrared (IR) thermography, incorporated with such image processing procedures as data statistics, noise removal and two-dimensional DFT (Discrete Fourier Transformation) for extracting features from the resulting thermographies. IRT, defined as the statistical mean value of the IR image matrix, was used as a measure of rock response, characterizing the full-face excavation, the staged excavation as a linear process and a non-linear process respectively by its time-Marching scheme within the IR radiation domain. The denoised IR images and the two-dimension Fourier spectra provide an enhanced understanding of the excavation response in terms of initiation, propagation and coalescence of rock damage in the spatial and frequency regimes respectively.