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In this research, the Strength and deformation behaviors, cracking process, and local stress evolution of sandstone specimens containing a circular opening and two joints (called H-J sandstone specimens in this study) were researched by experiment and numerical simulation (two-dimension particle flow code). The effect of different joint positions around the opening has been specifically studied by changing the ligament angle (${\beta }$). The test results show that peak strength and peak strain firstly decrease then increase with the increasing ${\beta }$, while the peak strain presents an overall upward trend. Three types of coalescence failure patterns between the opening and joints formed, and the corresponding cracking process and acoustic emission (AE) characteristics are highly related to the ligament angle. Based on the micro-parameters calibration, a good agreement was achieved between experimental and numerical simulation. The numerical results show that the local stress evolution around the opening is highly corresponding to the cracking process. The microcracks initiation and propagation cause obvious stress fluctuations, drops or increasements of minimum principal stress, while the cracks coalescence results in obvious reduction of maximum principal stress and drops of stress-strain curve. It also be found that the stress distribution and magnitude around the opening tend to be closely related to both coalescence failure and strength characteristics of H-J specimens. Finally, the cracking mechanism between the opening and joints was revealed based on particle displacement fields. The results show that different cracking mechanism may cause different local stress changes, which finally determines the overall mechanical behavior of specimens.

BackgroundObtaining comprehensive epidemic information for specific global infectious diseases is crucial to travel health. However, different infectious disease information websites may have different purposes, which may lead to misunderstanding by travelers and travel health staff when making accurate epidemic control and management decisions. ObjectiveThe objective of this study was to develop a Global Infectious Diseases Epidemic Information Monitoring System (GIDEIMS) in order to provide comprehensive and timely global epidemic information. MethodsDistributed web crawler and cloud agent acceleration technologies were used to automatically collect epidemic information about more than 200 infectious diseases from 26 established epidemic websites and Baidu News. Natural language processing and in-depth learning technologies have been utilized to intelligently process epidemic information collected in 28 languages. Currently, the GIDEIMS presents world epidemic information using a geographical map, including date, disease name, reported cases in different countries, and the epidemic situation in China. In order to make a practical assessment of the GIDEIMS, we compared infectious disease data collected from the GIDEIMS and other websites on July 16, 2019. ResultsCompared with the Global Incident Map and Outbreak News Today, the GIDEIMS provided more comprehensive information on human infectious diseases. The GIDEIMS is currently used in the Health Quarantine Department of Shenzhen Customs District (Shenzhen, China) and was recommended to the Health Quarantine Administrative Department of the General Administration of Customs (China) and travel health–related departments. ConclusionsThe GIDEIMS is one of the most intelligent tools that contributes to safeguarding the health of travelers, controlling infectious disease epidemics, and effectively managing public health in China.

With ethylene-vinyl acetate-glycidyl methacrylate (EVM-GMA) rubber as matrix, γ-aminopropyltriethoxysilane (APTES) as grafting monomer and azodicarbonamide as foaming agent, double crosslinked foaming materials were prepared by combination of water crosslinking and peroxide crosslinking. The cell morphology, dynamic mecha-nical properties, and physical and mechanical properties of the foaming materials were investigated by scanning electron microscopy, dynamic mechanical property spectrometer and electronic universal tes-ting machine. The results showed that the double crosslinked foaming process could be realized, and the crosslinking network formed by water crosslin-king could effectively improve the uniformity and dispersion of cell size. When the amount of dicumyl peroxide was 0.25 phr (mass), the double crosslinked foam material had the narrowest cell size distribution, the best foaming effect, and better energy absorption effect, which was suitable for application of damping materials.

Abstract The process of chemical exchange saturation transfer (CEST) is quantified by evaluating a Z-spectra, where CEST signal quantification and Z-spectra fitting have been widely used to distinguish the contributions from multiple origins. Based on the exchange-dependent relaxation rate in the rotating frame (R ex), this paper introduces an additional pathway to quantitative separation of CEST effect. The proposed R ex-line-fit method is solved by a multi-pool model and presents the advantage of only being dependent of the specific parameters (solute concentration, solute‐water exchange rate, solute transverse relaxation, and irradiation power). Herein we show that both solute‐water exchange rate and solute concentration monotonously vary with R ex for Amide, Guanidino, NOE and MT, which has the potential to assist in solving quantitative separation of CEST effect. Furthermore, we achieve R ex imaging of Amide, Guanidino, NOE and MT, which may provide direct insight into the dependency of measurable CEST effects on underlying parameters such as the exchange rate and solute concentration, as well as the solute transverse relaxation.

ABSTRACT: Spermatogenesis is a continuous process in which functional sperm are produced through a series of mitotic and meiotic divisions and morphological changes in germ cells. The aberrant development and fate transitions of spermatogenic cells cause hybrid sterility in mammals. Cattle-yak, a hybrid animal between taurine cattle (Bos taurus) and yak (Bos grunniens), exhibits male-specific sterility due to spermatogenic failure. In the present study, we performed single-cell RNA sequencing analysis to identify differences in testicular cell composition and the developmental trajectory of spermatogenic cells between yak and cattle-yak. The composition and molecular signatures of spermatogonial subtypes were dramatically different between these 2 animals, and the expression of genes associated with stem cell maintenance, cell differentiation and meiotic entry was altered in cattle-yak, indicating the impairment of undifferentiated spermatogonial fate decisions. Cell communication analysis revealed that signaling within different spermatogenic cell subpopulations was weakened, and progenitor spermatogonia were unable to or delayed receiving and sending signals for transformation to the next stage in cattle-yak. Simultaneously, the communication between niche cells and germ cells was also abnormal. Collectively, we obtained the expression profiles of transcriptome signatures of different germ cells and testicular somatic cell populations at the single-cell level and identified critical regulators of spermatogonial differentiation and meiosis in yak and sterile cattle-yak. The findings of this study shed light on the genetic mechanisms that lead to hybrid sterility and speciation in bovid species.

Bactericides are a common method for preventing and controlling microbiologically influenced corrosion (MIC) in the offshore oil and gas extraction industry.However，bactericides may cause changes in the behavior of microbial corrosion，and the presence of petroleum will also have a certain impact on the effectiveness of bactericides.In this work， the effect of tetrakis (hydroxymethyl) phosphonium sulfate(THPS) on the corrosion behavior of biocide sulfate-reducing bacteria (Desulfobaculum bizertense) in the presence of petroleum was studied by cell counting， corrosion weight loss， surface analysis and electrochemical analysis.Results showed that although THPS could inhibit the growth of D.bizertensis，it aggravated the corrosion of D.bizertensis on X70 pipeline steel.Meantime，the addition of petroleum further increased the corrosion potential， indicating that even with the addition of bactericides， petroleum still promoted the corrosion of D. bizertensis on X70.The above result provided a reference for the rational use of bactericides in marine oily environments.

Total knee arthroplasty (TKA) is an effective treatment for end-stage knee joint diseases. The debate over preserving or sacrificing the posterior cruciate ligament (PCL) in mobile-bearing TKA (MB TKA) still needs to be solved due to the lack of high-quality evidence, particularly meta-analyses comparing these techniques. This study aims to conduct a meta-analysis to compare the outcomes of PCL retention (CR) and PCL sacrifice (PS) in terms of clinical and functional knee scores, range of motion, complication rates, and revision rates and to validate these findings through animal experiments. A comprehensive search was conducted using MEDLINE, Cochrane, and Embase databases. Relevant studies were selected for the meta-analysis using RevMan 5.3. Additionally, an animal experiment using Sprague-Dawley rats simulated MB TKA to compare the effects of PCL retention and sacrifice surgeries. 12 studies were included in the meta-analysis. No significant differences were found between CR and PS techniques regarding HSS, KSS, KSFS, WOMAC, ROM, and medial/lateral instability. However, CR MB showed slight superiority in NKJS, while PS MB had better outcomes in complication and revision rates. In the animal study, CR rats exhibited significant early postoperative inflammation, but both groups’ knee structures gradually normalized. The meta-analysis indicates that PCL retention (CR MB) and sacrifice (PS MB) have similar effects on various clinical and functional knee scores. However, PS MB is significantly better at reducing complications and revision rates. The animal experiment confirms PS MB’s advantages in reducing inflammation and promoting joint recovery. Despite the strong evidence, long-term follow-up and larger-scale randomized controlled trials are necessary to confirm these findings.

Abstract The brain presents age-related structural and functional changes in the human life, with different extends between subjects and groups. Brain age prediction can be used to evaluate the development and aging of human brain, as well as providing valuable information for neurodevelopment and disease diagnosis. Many contributions have been made for this purpose, resorting to different machine learning methods. To solve this task and reduce memory resource consumption, we develop a mini architecture of only 10 layers by modifying the deep residual neural network (ResNet), named ResNet mini architecture. To support the ResNet mini architecture in brain age prediction, the brain age dataset (OpenNeuro #ds000228) that consists of 155 study participants (three classes) and the Alzheimer MRI preprocessed dataset that consists of 6400 images (four classes) are employed. We compared the performance of the ResNet mini architecture with other popular networks using the two considered datasets. Experimental results show that the proposed architecture exhibits generality and robustness with high accuracy and less parameter number.

Abstract Combinatorial optimization problems are ubiquitous and computationally hard to solve in general. Quantum approximate optimization algorithm (QAOA), one of the most representative quantum-classical hybrid algorithms, is designed to solve combinatorial optimization problems by transforming the discrete optimization problem into a classical optimization problem over continuous circuit parameters. QAOA objective landscape is notorious for pervasive local minima, and its viability significantly relies on the efficacy of the classical optimizer. In this work, we design double adaptive-region Bayesian optimization (DARBO) for QAOA. Our numerical results demonstrate that the algorithm greatly outperforms conventional optimizers in terms of speed, accuracy, and stability. We also address the issues of measurement efficiency and the suppression of quantum noise by conducting the full optimization loop on a superconducting quantum processor as a proof of concept. This work helps to unlock the full power of QAOA and paves the way toward achieving quantum advantage in practical classical tasks.

The composition of volatile compounds in beer is crucial to the quality of beer. Herein, we identified 23 volatile compounds, namely, 12 esters, 4 alcohols, 5 acids, and 2 phenols, in nine different beer types using GC–MS. By performing PCA of the data of the flavor compounds, the different beer types were well discriminated. Ethyl caproate, ethyl caprylate, and phenylethyl alcohol were identified as the crucial volatile compounds to discriminate different beers. PLS regression analysis was performed to model and predict the contents of six crucial volatile compounds in the beer samples based on the characteristic wavelength of the FTIR spectrum. The R2 value of each sample in the prediction model was 0.9398–0.9994, and RMSEP was 0.0122–0.7011. The method proposed in this paper has been applied to determine flavor compounds in beer samples with good consistency compared with GC–MS.