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Landscape stability is a paramount concern within the field of landscape ecology. Indices of landscape patterns not only facilitate an effective analysis of land use transformations but also delve into the mechanisms of landscape disturbances across various spatial and temporal dimensions. Utilizing land use data spanning from 2014 to 2022 for the Shibing and Libo-Huanjiang South China Karst (SCK) World Heritage Sites (WHSs), this study delves into the landscape dynamics of these areas over the past 8 years. This investigation employs landscape pattern indices and a moving window technique to construct a landscape stability evaluation model, incorporating indices such as the Contagion Index, Patch Density, and Total Edge Contrast. Moreover, the study employs Moran's I, a spatial autocorrelation index, to scrutinize the shifts in geographical heterogeneity of landscape stability within the said period. The findings reveal: (1) Between 2014 and 2022, the landscape patterns of the Shibing and Libo-Huanjiang WHSs have undergone significant transformations, with Woodland emerging as the predominant landscape type and its area exhibiting an upward trend in recent years. (2) The level of fragmentation within the research area has decreased, landscape diversity has diminished, and the aggregation index has risen, according to the landscape pattern indices from 2014 to 2022, indicating that conservation measures have significantly influenced the evolution of landscape patterns. (3) Throughout most of the study period, landscape stability predominantly remained at a relatively stable level, albeit with noticeable fluctuations in years heavily impacted by human activities. (4) The areas of high-high agglomeration and the hotspots of the heritage sites were primarily concentrated within the core zones of these sites, suggesting focused areas of conservation and landscape integrity. [ABSTRACT FROM AUTHOR]

Carpal tunnel syndrome (CTS) is one of the most common work-related musculoskeletal disorders. The present study sought to identify putative causal proteins for CTS. We conducted a two-sample Mendelian randomization (MR) analysis to evaluate the causal association between 2859 plasma proteins (N = 35,559) and CTS (N = 1,239,680) based on the published GWAS summary statistics. Then we replicated the significant associations using an independent plasma proteome GWAS (N = 10,708). Sensitivity analyses were conducted to validate the robustness of MR results. Multivariate MR and mediation analyses were conducted to evaluate the mediation effects of body mass index (BMI), type 2 diabetes (T2D), and arm tissue composition on the association between putative causal proteins and CTS. Colocalization analysis was used to examine whether the identified proteins and CTS shared causal variant(s). Finally, we evaluated druggability of the identified proteins. Ten plasma proteins were identified as putative causal markers for CTS, including sCD14, PVR, LTOR3, CTSS, SIGIRR, IFNL3, ASPN, TM11D, ASIP, and ITIH1. Sensitivity analyses and reverse MR analysis validated the robustness of their causal effects. Arm tissue composition, BMI, and T2D may play a fully/partial mediating role in the causal relationships of ASIP, TM11D, IFNL3, PVR, and LTOR3 with CTS. The association of ASPN and sCD14 with CTS were supported by colocalization analysis. Druggability assessment demonstrated that sCD14, CTSS, TM11D, and IFNL3 were potential drug therapeutic targets. The present study identified several potential plasma proteins that were causally associated with CTS risk, providing new insights into the pathogenesis of protein-mediated CTS and offering potential targets for new therapies. [ABSTRACT FROM AUTHOR]

Tunnelling in urban areas should be aware of deviations from the design tunnel axis, referred to also as 'misalignment'. Significant misalignment can cause unfavourable soil deformations, threatening adjacent properties, and sustainable development of underground space. In this study, the potential of applying machine learning (ML) and deep learning (DL) algorithms to EPB shield posture prediction and anomaly detection was explored. A framework, including data pre-processing, development of prediction models, performance evaluation, and anomaly detection, was proposed to tackle the said issue. The principal component analysis (PCA) was introduced not only to eliminate outliers but also to isolate salient data features using the Pearson's correlation coefficient (PCC). Also, the partial dependence analysis aimed to marginalize other features and established the relationship between an individual tunnelling parameter and EPB shield position. Then the feature-based subseries were normalized for training and examining the DL-based Long Short-Term Memory (LSTM) and ML-based ensemble EPB shield position predictors. On the other hand, three anomaly detectors founded on three ML algorithms were developed to prevent snakelike advance. Results showed that the DL-based LSTM predictor outperformed the ML-based ensemble predictor owing to its relative insensitivity to lags of unknown duration between important events. The thrust force dominated EPB shield position. The LSTM model prevented the accuracy of EPB shield position prediction from disturbing by gravels surrounding the design tunnel axis or artificial intervention. [ABSTRACT FROM AUTHOR]

Online Judge (OJ) is an important aid for programming learning that can help students evaluate learning effects in real-time, while teachers can adjust practice tasks in time according to the records of the tool. With these advantages, OJ shows great value for promoting teaching and learning in programming. The existing OJ system usually only provides information such as problem status list and recent rank list. However, it is unable to provide teachers with more fine-grained analysis information, such as the distribution of students' incorrect responses and level of knowledge mastery. And it also cannot provide students with effective comparative information on their learning status. This research developed a visual learning analytics dashboard named VisOJ for the OJ system, which includes two types of user interfaces: teacher and student. The teacher interface presents students' learning status and ranking trends, which help teachers monitor and give feedback on their learning activities. The student interface provides views such as error type analysis and evaluation, which promote students' self-reflection and self-regulation. Preliminary case studies and expert interviews prove the usability of the dashboard. In the end, we summarize our main work and suggest future research directions. [ABSTRACT FROM AUTHOR]

Wetlands are the most biologically diverse ecosystems on Earth. The isolation of Streptomyces strains from wetlands is helpful to study their diversity and functions in such habitats. In this study, six strains of Streptomyces were isolated from the rhizosphere soil of three plant species in the Huaxi Wetland at Guiyang and were identified as Streptomyces galilaeus, S. avidinii, S. albogriseolus, S. albidoflavus, S. spororaveus, and S. cellulosae, respectively. The six strains all solubilized phosphate, fixed nitrogen, and produced ACC deaminase and siderophores, and four strains also secreted indole-3-acetic acid. The six strains had the ability to resist to certain degrees of salinity, drought, and acidic/alkaline pH stress. In addition, the S. avidinii WL3 and S. cellulosae WL9 strains significantly promoted seed germination of mung bean, pepper, and cucumber, especially the WL3 strain. A pot experiment further showed that WL3 significantly promoted the growth of cucumber seedlings. Thus, strains of six species of Streptomyces with multiple plant growth-promoting characteristics were isolated from the wetland. These results lay a foundation for their potential use as microbial agents for seed-coating treatments. [ABSTRACT FROM AUTHOR]

Intergenerational relationships have become increasingly crucial for maintaining well-being in aging families. Under a changing sociocultural background, families in Hong Kong increasingly exhibit diverse intergenerational relationships and functioning. Focusing on families with mutiple children, this study investigated how the characteristics of parents and their adult children jointly affect different domains of intergenerational relationship quality. A two-stage stratified random sampling design was adopted. Face-to-face questionnaire interviews were conducted between November 2016 and March 2017 with 1,001 Hong Kong residents aged ≥ 50 years. Data of 612 parents and 1,745 adult children were included for analysis. Hierarchical linear modeling was performed to examine child- and parent-level correlates of intergenerational relationship quality. Parents who were female, were married, had higher self-perceived economic status, owned a house, and had fewer depressive symptoms, exhibited higher intergenerational relationship quality. Parents' age was positively related to affectual closeness, whereas their educational level was negatively related to both affectual closeness and conflict. More favorable intergenerational relationships were reported by aging parents whose adult children were younger, female, and married. Children with higher educational levels exhibited higher levels of both affectual closeness and conflict with their parents. Moreover, affectual closeness was found to be transmitted between generations. The findings can help improve awareness of the factors affecting the different domains of intergenerational relationships, thus informing the development of targeted services and interventions to promote family relationships and well-being. [ABSTRACT FROM AUTHOR]

The two-sample Mendelian randomization (MR) study revealed a causal association of plasma proteins with osteoporosis (OP) and osteoarthritis (OA). Bone mineral density (BMD) is the gold standard for the clinical assessment of OP. Recent studies have shown that plasma proteins play an essential role in the regulation of bone development. However, the causal association of plasma proteins with BMD and OA remains unclear. We estimated the effects of 2889 plasma proteins on 2 BMD phenotypes and 6 OA phenotypes using two-sample MR analysis based on the genome-wide association study summary statistics. Then, we performed sensitivity analysis and reverse-direction MR analysis to evaluate the robustness of the MR analysis results, followed by gene ontology (GO) enrichment analysis and KEGG pathway analysis to explore the functional relevance of the identified plasma proteins. Overall, we observed a total of 257 protein-estimated heel BMD associations, 17 protein-total-body BMD associations, 2 protein-all-OA associations, and 2 protein-knee-OA associations at PFDR < 0.05. Reverse-direction MR analysis demonstrated that there was little evidence of the causal association of BMD and OA with plasma proteins. GO enrichment analysis and KEGG pathway analysis identified multiple pathways, which may be involved in the development of OP and OA. Our findings recognized plasma proteins that could be used to regulate changes in OP and OA, thus, providing new insights into protein-mediated mechanisms of bone development. [ABSTRACT FROM AUTHOR]

Biofilm-forming Staphylococcus aureus can easily accumulate on various food contact surfaces which induce cross-contamination and are difficult to eliminate in the food industry. This study aimed to evaluate the anti-biofilm effects of natural product biochanin A against S. aureus. Results showed that biochanin A effectively eradicated established S. aureus biofilms on different food-contact materials. Fluorescence microscopic analyses suggested that biochanin A disintegrated the established biofilms by dissociate extracellular polymeric substance (EPS) in matrix. In addition, biochanin A at the sub-MIC concentration also effectively inhibited the biofilm formation by regulating the expression of biofilm-related genes (icaA, srtA, eno) and suppressing the release of EPS in biofilm matrix. Molecular docking also demonstrated that biochanin A conducted strong interactions with biofilm-related proteins (Ica A, Sortase A, and Enolase). These findings demonstrated that biochanin A has the potential to be developed as a potent agent against S. aureus biofilm in food industries. Key points: • Anti-biofilm effect of biochanin A against S. aureus was revealed for the first time. • Biofilm of S. aureus on various food-contact surfaces were efficiently eradicated. • Biochanin A prevented S. aureus biofilm formation via reducing EPS production. [ABSTRACT FROM AUTHOR]

We investigate the dynamics of measurement-induced nonlocality (MIN) with two spins in an ideal single-mode optical cavity. The two-spin entangled states are generated firstly under the photon coherent state assumption by means of the variational method. The time evolution of MIN is then examined based on the derived analytical expressions of the reduced density operator of two spins. It is shown that MIN remains in its upper bound all the time and independent of the average photon number of the coherent field when the two spins are initially in the singlet state, which just is the eigenstate of our model. However, for the initial general two-spin entangled states of antiparallel and parallel spin polarizations, MIN strongly depends on the average photon number and initial angle parameters. We provide a detailed analysis of MIN dynamics by the numerical calculation, and reveal some significant results. [ABSTRACT FROM AUTHOR]

The sintered NdFeB is widely used in many fields due to its excellent magnetic properties. However, the sintered NdFeB is characterized by its high hardness and brittleness. Therefore, its application has been limited. In order to improve its machining properties by electrical discharge machining (EDM), the deionized water is used as the dielectric medium, and then the sintered NdFeB is processed by the electrical discharge machining milling (EDM-M). The machining properties are studied by the comparative experiments. Changing the set value of the current, get the material removal rate (MRR), the surface roughness (SR) and the tool wear rate (TWR) of the die-sinking EDM in the kerosene-based medium (KEDM), the EDM-M in the kerosene-based medium (KEDM-M), the die-sinking EDM in the deionized water (DEDM), and the EDM-M in the deionized water (DEDM-M), respectively. By the scanning electron microscope (SEM), the influences of current on the material removal mechanism and surface formation mechanism of the DEDM-M are analyzed. Meanwhile, the characteristic of its surface micro-morphology influenced by current is analyzed. Combined SEM with energy-dispersive spectroscopy (EDS), the cross-section of the sintered NdFeB by the DEDM-M is analyzed. It is revealed by the comparative experiments that, for the sintered NdFeB by the DEDM-M, the interval of the machining parameter is wide; the value of SR is lowest obviously under low current set value; the variations of its MRR, SR, and TWR are regular; the controllability is good. The regression equations for the machining properties of the DEDM-M are obtained and its analysis of variance (ANOVA) is good. The analysis on the SEM of its machined surface indicates that the material removal and surface formation of the DEDM-M are effected synthetically by fusion and stress. The change of current leads to the difference in surface micro-morphology by fusion removal, globule, microvoid, microcrack, and surface micro-morphology by stress removal, and then leads to differences in MRR and SR, respectively. The results of analysis on the cross-section reveal that there are four categories from the surface to the matrix. They are recast layer after fusion with plenty of rare earth elements and minor oxygen which is amorphous and sheet, recast layer after fusion with plenty of iron element and minor rare earth elements which is strip and granular, micro-morphology by stress, and heat affected layer that is composed of large grains with thin grain boundaries. [ABSTRACT FROM AUTHOR]

Phosphatidylinositol 3-kinase (PI3K) is a key regulatory kinase in the PI3K/AKT/mTOR signaling pathway, which is involved in the regulation of cell proliferation, differentiation, apoptosis, and angiogenesis. Class IA PI3K isoforms γ and δ share a highly homologous ATP binding site and are distinguished by only a few residues around the binding site. Subtype-selective inhibitors have been proven to have great advantages in tumor treatment. Preliminary studies have obtained PI3K inhibitors bearing a benzimidazole structural motif with a certain selectivity for PI3Kδ and PI3Kγ subtypes. On this basis, we investigated the selective inhibitory mechanism of PI3Kδ and PI3Kγ using four developed inhibitors via molecular docking, molecular dynamics, binding free energy calculations, and residue energy decomposition. This study could provide references for the further development of PI3K-isoform-selective inhibitors. [ABSTRACT FROM AUTHOR]

The foodborne pathogen Staphylococcus aureus continues to challenge the food industry due to the pathogenicity and tolerance of the bacterium. As a common storage condition for frozen food during transportation, distribution, and storage, freezing does not seem to be entirely safe due to the cold tolerance of S. aureus. In addition, our study indicated that the biofilm formation ability of S. aureus was significantly increased in response to freezing stress. To explore the molecular mechanism regulating the response to freezing stress, the proteomics signature of S. aureus after freezing stress based on tandem mass tag (TMT) labeling and liquid chromatography tandem mass spectrometry (LC–MS/MS) was analyzed. Gene Ontology and pathway analysis revealed that ribosome function, metabolism, RNA repair, and stress response proteins were differentially regulated (P < 0.05). Furthermore, transpeptidase sortase A, biofilm operon icaADBC HTH-type negative transcriptional regulator IcaR, and HTH-type transcriptional regulator MgrA were involved in the modulation of increased biofilm formation in response to freezing stress (P < 0.05). Moreover, significant lysine acetylation and malonylation signals in the S. aureus response to freezing stress were observed. Collectively, the current work provides additional insight for comprehending the molecular mechanism of S. aureus in response to freezing stress and presents potential targets for developing strategies to control S. aureus. Key points: • TMT proteomic analysis was first used on S. aureus in response to freezing stress. • Ribosome-, metabolism-, and biofilm-related proteins change after freezing stress. • Increased biofilm formation in S. aureus responded to freezing stress. [ABSTRACT FROM AUTHOR]

Copper based ternary and quaternary quantum confined nanostructures have attracted huge attention over recent years due to their potential applications in photonics, photovoltaics, imaging, sensing and other areas. However, anisotropic nanoheterostructures of this type are still poorly explored to date, despite numerous predictions of the distinctive optical properties of these highly fluorescent heavy metal free nanostructures. Here, we report new fluorescent multicomponent Cu–In–(Zn)–S/ZnS nanoheterostructures with a unique anisotropic "ice-cream cone" like morphology. These nanostructures have been prepared with a seeded growth technique and exhibit distinct photophysical properties with maximum emission in the visible range (≈ 640 nm) and long photoluminescence lifetimes (τaverage ≥ 300 ns). In depth time interval studies have been carried out to better understand the step by step growth mechanism of this distinct "ice-cream cone" like geometry. We have demonstrated that the crystal structure evolution from the zinc blende Cu–In–S core to the wurtzite "ice cream cone" like Cu–In–(Zn)–S/ZnS nanocrystals plays a key role in the origin of this morphology. This research opens new possibilities to produce unique fluorescent Cu-based multicomponent anisotropic heteronanostructures, while also offering a distinctive insight into the design of bespoke nanostructures, which could find a range of potential applications. [ABSTRACT FROM AUTHOR]

Complex geological conditions and/or inappropriate shield tunnel boring machine (TBM) operation can significantly degrade both the excavation and safety of tunnel construction. In recent years, the excavation behaviour of shield TBMs has been a popular topic in the literature given the large volume of data automatically collected by modern shields. These datasets provide an excellent opportunity to apply advanced data analysis techniques to improve predictions of shield tunnelling excavation behaviour. In this study, a framework to develop machine learning (ML)-based regression models for predicting the behaviour of an earth pressure balance (EPB) shield machine using tunnelling parameters is proposed. The feasibility of four ML algorithms, namely Linear Regression (LR), Decision Tree Regression (DTR), Support Vector Regression (SVR), and Gradient Boosting Regression (GBR), to predict EPB shield excavation behaviour is explored through their application to a recent tunnelling case history in sandy soils. The results show that the misestimates were primarily attributed to a reduction of screw conveyor rotational speed (SCRS), induced by a lower injection volume, the artificial manipulation of penetration rate (PR), the local variations of total jacking load, and the use of 'breakout' cutterwheel torque (CT). The GBR model provided the best performance, while LR often performs the worst due to its inability to handle highly nonlinear relationships. DTR prevented the overfitting problem by using a lower max depth parameter towards sacrificing its accuracy. The performance of SVR was seriously affected by loss functions. The proposed optimisation scheme that prevents the over-smoothing problem during the STL decomposition elevates further the prediction accuracy. [ABSTRACT FROM AUTHOR]

Introduction: In 2018, a renal risk score of antineutrophil cytoplasmic antibody (ANCA)–associated glomerulonephritis (AAGN) based on estimated glomerular filtration rate (eGFR), normal glomeruli, and tubular atrophy/interstitial fibrosis (TA/IF) was proposed to predict renal outcomes. We aimed to evaluate this renal risk score in a myeloperoxidase (MPO)–ANCA predominant population in Northeast China. Methods: We retrospectively analyzed the clinicopathologic data of 65 patients biopsy-proven from a Chinese medical center. Each patient was assessed by eGFR, normal glomeruli, and TA/IF, and the renal outcome was evaluated using the renal risk score. Results: In our study, 95.4% of patients were ANCA positive (78.5% MPO-ANCA positive and 16.9% proteinase 3-ANCA positive). The average follow-up period was 14.3 months. Thirty-four patients (52.3%) reached end-stage renal disease (ESRD). Based on the renal risk score, 8 (12.3%), 31 (47.7%), and 26 (40%) patients were divided into the low-risk, medium-risk, and high-risk groups, respectively. Kaplan–Meier survival curves revealed the high-risk group had worse renal outcomes than the low-risk group (p<0.01) and the medium-risk group (p<0.01), but the renal outcome did not differ between the low-risk and medium-risk groups (p>0.017). Similar results were obtained by the competitive survival analysis. The AUC for 3-year overall ESRD predictions was 0.845. In the regression analysis, the renal risk score was a favorable predictor for the development of ESRD (HR 3.13, 95%CI 1.58–6.19, p=0.001). Conclusion: The renal risk score is a preferred index that can predict ESRD in Chinese AAGN patients, especially in the high-risk group with worse renal outcomes. Key Points • The eGFR and percentage of normal glomeruli were valuable predictors of renal outcome, whereas TA/IF was not. • We confirmed the renal risk score is a preferred index that can predict ESRD in Chinese AAGN patients. • Based on the renal risk score, the high-risk group had worse renal outcomes than the low-risk group and the medium-risk group. [ABSTRACT FROM AUTHOR]

We in this paper investigate the spin squeezing in relation with the phase transition from the normal to superradiant phases for two atoms in an optical cavity. The squeezing vanishes in the normal phase and jumps sharply to the maximum bound above the critical point of phase transition. In the high atom-field coupling regime, the squeezing vanishes again when the atom-field coupling reaches a threshold value. The squeezing alternates between two spin components in the intermediate region of atom-field coupling. An interesting observation is that the two spin components are squeezed alternately with the variation of phase angle of the cavity field. The squeezing factor indeed can be used to probe the phase transition and coherent-field properties as well. [ABSTRACT FROM AUTHOR]

The magnetized sintered NdFeB (MS-NdFeB) permanent magnet material is difficult to machine due to high hardness, brittleness, and magnetic force. In this paper, the electrical discharge machining (EDM) of the MS-NdFeB workpiece is studied to improve the machining process of the MS-NdFeB. In addition to the material removal rate (MRR) and the surface roughness (SR), the change rate of the magnetic flux density (MCR) for the MS-NdFeB is proposed and used as the research index of their machining effect by the EDM process. By orthogonal experiments, using the intuitive analysis method and the analysis of variance (ANOVA) method, study the influences of the peak current, the pulse on time, the pulse off time, and the magnetic field intensity of the processing area (MF) on the MRR, the SR, and the MCR. The scanning electron microscope (SEM) pictures of the machined MS-NdFeB surfaces are obtained based on the experimental design with a one-factor variation. The comparative experiment is performed to reveal the change of the MCR in EDM. The intuitive analysis of the orthogonal experimental result reveals regularities of influences. The ANOVA reveals the significance of influences. The regularities and significance of influences of machining parameters on the machining effects are analyzed assisted by the analysis on these SEM pictures and the comparative experimental results. The optimal combinations of machining parameters for MRR, SR, and MCR are obtained by single-objective optimization. The verification experiments prove the reliability of the single objective optimization results. [ABSTRACT FROM AUTHOR]

We study the dynamic creation of two different geometric quantum discords (GQDs) defined, respectively, via the Hilbert–Schmidt norm (GQD-2) and trace norm (GQD-1) between the two qubits, which are prepared initially in a zero discord two-qubit X-shape state, and subject to a two layers environment that consists of a lossy cavity coupled to the W-coupled lossy cavities. We find that the GQD-2 and GQD-1 exhibit oscillatory behavior in the regime of the strong coupling between the qubit and first-layer cavity environment. And in both the weak and strong coupling regimes, for the greater the number of cavities in the second-layer environment, the GQDs reach their peak value in a larger time and go to zero more slowly. But in the qubit–cavity coupling, the coupling between two nearest neighbor cavities and the decay rate of cavities in the second-layer environment have the opposite effect on the GQDs. Furthermore, the maximum value of GQDs remains unchanged and the steady value increases, or they both decrease, depending on the threshold value of coupling between the two layers environment. Finally, we propose an effective strategy to improve the GQD-2 and GQD-1 by using local filtering operation. [ABSTRACT FROM AUTHOR]

Thiazole ring is an important active molecular skeleton of drugs. Thiazole in natural products and drugs are usually harmlessly eliminated. However, hepatotoxic reactions may occur due to the biological activation of thiazole to produce reactive thioamide. A typical example is hepatotoxic sudoxicam and safety meloxicam. The only structural difference between them is a methyl group on C5 position of thiazole in meloxicam. The molecular basis for the difference remains unknown and the bioactivation mechanism of the thiazole ring is still obscure. Quantum chemical calculations were performed to elucidate the activation mechanism of the thiazole ring under P450 catalysis, and the influence of the substituents on the activation pathways of thiazole ring was also studied. The calculated results show that the activation of thiazole is closely related to the substituents on the thiazole and spin state of Cpd I. The thiazole and substituted thiazole directly open the ring when catalyzed by doublet spin state Cpd I that catalyzed by the quartet spin state Cpd I can open the ring directly or indirectly, which is related to the substituents. Thiazoles modified with electron-donating substituents mainly undergo direct ring opening, while thiazoles modified with electron-withdrawing groups or weak electron-donating groups mainly undergo indirect ring-opening process accompanied by intermediate formation. The research results laid the foundation for the design of thiazole ring drugs, and also laid a theoretical foundation for the study of reducing the toxicity of thiazole ring drugs. [ABSTRACT FROM AUTHOR]

Oligoasthenozoospermia (OA) is one of the most common types of male infertility affecting sperm count and sperm motility. Unfortunately, it is difficult for existing drugs to fundamentally improve the sperm quality of OA patients, because the pathological mechanism of OA has not been fully elucidated yet. Morinda officinalis–Lycium barbarum coupled-herbs (MOLBCH), as traditional Chinese Medicines, has been widely used for treating OA over thousands of years, but its molecular mechanism is still unclear. For this purpose, we adopted a comprehensive approach integrated network pharmacology and molecular docking to reveal the bioactive components and potential targets of MOLBCH against OA. The results showed that MOLBCH alleviated apoptosis, promoted male reproductive function, and reduced oxidant stress in the treatment of OA. Ohioensin-A, quercetin, beta-sitosterol and sitosterol were the key bioactive components. Androgen receptor (AR), Estrogen receptor (ESR1), Mitogen-activated protein kinase 3 (MAPK3), RAC-alpha serine/threonine-protein kinase (AKT1), Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) were the core potential targets. PI3K/Akt signaling pathway, prostate cancer, AGE-RAGE signaling pathway in diabetic complications were the most representative pathways. Moreover, molecular docking was performed to validate the strong binding interactions between the obtained core components and targets. These observations provide deeper insight into the pathogenesis of OA and can be used to design new drugs and develop new therapeutic instructions to treat OA. [ABSTRACT FROM AUTHOR]

A sensitive and selective fluorescent nitrogen-doped carbon dots (N-CDs) probe was synthesized by using glucosamine as a single reagent in a one-step hydrothermal treatment and was also characterized by UV-Vis spectrophotometer, fluorescence spectrophotometer, transmission electron microscope (TEM), Fourier transform infrared (FTIR) spectrometer, X-ray diffractometer (XRD), and X-ray photoelectron spectrometer (XPS). N-CDs exhibited a superior water solubility and an excellent fluorescence characteristic and was used as a fluorophore to measure ClO− and NO2− based on their oxidation in the presence of Fe2+. The quenching mechanism of ClO− and NO2− to the system probe of Fe2+@N-CDs was also demonstrated. The detection limit of the probe to ClO− was 0.75 μM in the linear range of 1 to 17.5 μM and for NO2− was 0.85 μM with the linear range of 2.5 to 20 μM. Speciation analysis of ClO− and NO2− could be distinguished due to the different reactive response time to the system probe of Fe2+@N-CDs, and the accuracy was further confirmed by detecting them in actual river water and tap water samples. [ABSTRACT FROM AUTHOR]

With the rapid development of intelligent and connected vehicles, the experimental road test for the advanced driving assistance system (ADAS) is dramatically increasing around the world. Considering its high cost and hazardous situations, simulation test based on a dummy model is becoming a promising way for ADAS road test practice to reduce the experiment expanses. This study proposed a methodology for the evaluation of the performance of human and dummies with distinct designed materials based on the data extracted from the Doppler effect of millimeter-wave radar. Echo data of 8 different angles from 0 to 360 degrees, with the an interval of 45 degrees, at the same distance between the test object and the signal source is collected. Meanwhile, the echo energy is collected for correlation modeling and analysis among groups. By evaluating the performance of humans and dummies via statistical analysis, a close correlation was found which results verified the substitutability of the dummy for the ADAS experiment test. The correlation coefficient between human and dummies ranges from 0.75 to 0.93. The support vector machine (SVM) model was developed and fitted to predict the echo energy in diverse environments. The mean average error (MAE) is 5.42–11.42 in the training and testing datasets while root mean square error (RMSE) is 0.43–0.90. The methods developed in the study can simulate the real ADAS road test environment and support future experimental research. [ABSTRACT FROM AUTHOR]

Given that combination with multiple biomarkers may well raise the predictive value of wound age, it appears critically essential to identify new features under the limited cost. For this purpose, the present study explored whether the gene expression ratios provide unique time information as an additional indicator for wound age estimation not requiring the detection of new biomarkers and allowing full use of the available data. The expression levels of four wound-healing genes (Arid5a, Ier3, Stom, and Lcp1) were detected by real-time polymerase chain reaction, and a total of six expression ratios were calculated among these four genes. The results showed that the expression levels of four genes and six ratios of expression changed time-dependent during wound repair. The six expression ratios provided additional temporal information, distinct from the four genes analyzed separately by principal component analysis. The overall performance metrics for cross-validation and external validation of four typical prediction models were improved when six ratios of expression were added as additional input variables. Overall, expression ratios among genes provide temporal information and have excellent potential as predictive markers for wound age estimation. Combining the expression levels of genes with ratio-expression of genes may allow for more accurate estimates of the time of injury. [ABSTRACT FROM AUTHOR]

High-resolution melting (HRM) analysis has been shown to be a time-saving method for the screening of genetic variants. To increase the precision of the diagnosis of osteogenesis imperfecta (OI), we used HRM to explore COL1A1/COL1A2 mutations in 87 Chinese OI patients and to perform population-based studies of the relationships between their genotypes and phenotypes. Peripheral blood samples were collected from the 87 non-consanguineous probands. The coding regions and exon boundaries of COL1A1/COL1A2 were detected by HRM and confirmed by Sanger sequencing. The functional effects of mutations were predicted through bioinformatic tools. Mutations were detected in 70.3% of familial cases and 40% of sporadic cases (p < 0.01). Compared with COL1A1 mutations, patients with COL1A2 mutations were more prone to severe phenotypes. Helical mutations (caused by substitution of the glycine within the Gly-X-Y triplet domain) were more likely to occur in patients with type III and IV (p < 0.05). Haploinsufficiency mutations (caused by frameshift, nonsense, and splice-site mutations) appeared more frequently in patients with type I (p < 0.05). Compared with the Sanger sequencing and whole exome sequencing (WES), HRM was found to reduce total costs by 78%- 80% in patients who had a positive HRM separate melting curve. Our findings suggest that HRM would greatly benefit small and understaffed hospitals and laboratories, and would facilitate the accurate diagnosis and early treatment of OI in remote and less developed regions. [ABSTRACT FROM AUTHOR]

A series of Ag3PO4/Bi2MoO6 p-n heterojunctions were assembled via the thin Bi2MoO6 nanosheets attached to the surface of rhombic dodecahedral Ag3PO4. The self-optimized Ag+/Ag0 pairs existed in the as-prepared heterojunction which are regarded as charge transmission bridge to accelerate the reaction. The samples presented much higher photocatalytic activity for the degradation of the target pollutions (completely degradation under solar light illuminating of 70 min for rhodamine B, 80 min for aureomycin and 70 min for tetracycline). It was found during the recycle test, photocatalytic performance of Ag3PO4/Bi2MoO6 underwent a successive increase since the second cycle in which the completely degradation of RhB was achieved after only 60 min visible light irradiation, confirming the composite is reusable with well stability. The oxidative mechanism was carefully investigation based on the scavengers trapping test, ESR spectra, XPS spectrum, photocurrent responses, and electrochemical impedance spectroscopy analysis. It proved Ag0 gradually generated from the as-prepared composite under solar light illuminating is fixed at an optimized content. The charge transfer was consequentially enhanced during the suitable level turning of Ag+/Ag0 pairs. Mediated by Ag0 sandwiched in p-n junction, the active species of the present photooxidative reaction experienced various period from ·OH and h+ in the initial reaction to the additional ·O2− in the successive recycle experiment owing to generation of the rectifying contact and Schottky junction. This study provides a new cognition for the improved reusability of the photocorrosion materials via the mutual transformation of metal monomers and ions. [ABSTRACT FROM AUTHOR]

A series of amphiphilic graft copolymers with hydrophilic polyethylene glycol (PEG) backbone and different densities of hydrophobic poly(butyl methacrylate) (PBMA) side chains were synthesized via a strategy combining polycondensation and through activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) technology. The hydrophilic macro-ATRP initiators having different amounts of active side bromo atoms were first synthesized by reacting the small ATRP initiator which contains two hydroxyl groups with hexamethylene diisocyanate (HDI) and polyethylene glycol (PEG1000). By graft from technology, the amphiphilic graft copolymers were then synthesized via ARGET ATRP of butyl methacrylate (BMA) using the hydrophilic macro-ATRP initiators. The steric shield effects of the macro-initiator lowered the polymerization rate and final conversion of BMA. The amphiphilic graft copolymers in aqueous media had critical micelle concentration (CMC) in the range of 10−6 to 10−7 g/mL, which were determined by fluorescence method using pyrene as a probe. The aggregate sizes of the amphiphilic graft copolymers in different solvents changed greatly, which were due to different interactions between the amphiphilic graft copolymers and the solvents and the incompatibility between PEG and PBMA segments. [ABSTRACT FROM AUTHOR]

Objectives: Total elbow arthroplasty (TEA) is becoming a popular alternative to arthrodesis for patients with end-stage elbow arthrosis and comminuted distal humeral fractures. Prior outcome studies have primarily focused on surgical findings. Our purpose is to determine the radiographic outcome of TEA and to correlate with clinical symptoms such as pain.Materials and Methods: This is an IRB-approved retrospective review from 2005 to 2015 of all patients with semiconstrained TEA. All available elbow radiographs and clinical data were reviewed. Data analysis included descriptive statistics and Kaplan-Meier survival curves for radiographic and clinical survival.Results: A total of 104 total elbow arthroplasties in 102 patients were reviewed; 75 % were in women and the mean patient age was 63.1 years. Mean radiographic follow-up was 826 days with average of four radiographs per patient. Seventy TEAs (67 %) developed radiographic complications, including heterotopic ossification (48 %), perihardware lucency (27 %), periprosthetic fracture (23 %), hardware subluxation/dislocation (7 %), polyethylene wear (3 %), and hardware fracture/dislodgement (3 %); 56 patients (55 %) developed symptoms of elbow pain or instability and 30 patients (30 %) underwent at least one reoperation. In patients with radiographic complications, 66 % developed elbow pain, compared to 19 % of patients with no radiologic complications (p = 0.001). Of the patients with radiographic complications, 39 % had at least one additional surgery compared to 0 % of patients without radiographic complications (p = 0.056).Conclusions: Radiographic complications are common in patients after total elbow arthroplasty. There is a strong positive association between post-operative radiographic findings and clinical outcome. Knowledge of common postoperative radiographic findings is important for the practicing radiologist. [ABSTRACT FROM AUTHOR]

Electrical discharge machining (EDM) with three-phase flow dielectric medium uses gas-liquid-powder mixture as the dielectric medium to improve the machining performance of the EDM. The appropriate selection of processing parameters makes for the improvement of machining properties for this EDM process. The material removal rate (MRR), tool wear rate (TWR), and surface roughness (SR) of EDM with three-phase flow dielectric medium are studied experimentally. The influence of process parameters, including peak current, pulse on time, pulse off time, flow rate, and concentration of powder particles, on these performance parameters, including MRR, TWR, and SR, are found out based on the orthogonal design experiment and the signal-to-noise ratio analysis. The reasons for these influences are analyzed. The optimal combination of process parameters to improve each single performance parameter is obtained. Verification tests are carried out. It is verified that the best combination of process parameters for MRR is powder concentration at the middle level, flow rate at the high level, pulse on time at the middle level, pulse off time at the low level, and peak current at the high level; the best for TWR is powder concentration at the low level, flow rate at the low level, pulse on time at the high level, pulse off time at the low level, and peak current at the low level; the best for Ra is powder concentration at the middle level, flow rate at the high level, pulse on time at the low level, pulse off time at the high level, and peak current at the low level, respectively. [ABSTRACT FROM AUTHOR]

Major elements and carbon isotopes of dissolved inorganic carbon (DIC) have been measured in the waters of Changbaishan mountain, a volcanic area in northeastern China, between June and September 2016 to decipher the origin of the CO involved in chemical weathering reactions. Spatial variations of major elements ratios measured in water samples can be explained by a change of the chemical composition of the volcanic rocks between the volcanic cone (trachytes) and the basaltic shield as evidenced by the variations in the composition of these rocks. Hence, DIC results from the neutralization of CO by silicate rocks. DIC concentrations vary from 0.3 to 2.5 mmol/L and carbon isotopic compositions of DIC measured in rivers vary from −14.2‰ to 3.5‰. At a first order, the DIC transported by rivers is derived from the chemical weathering's consumption of CO with a magmatic origin, enriched in C (−5%) and biogenic soil CO with lower isotopic compositions. The highest δC values likely result from C isotopes fractionation during CO degassing in rivers. A mass balance based on carbon isotopes suggest that the contribution of magmatic CO varied from less than 20% to more than 70%. Uncertainties in this calculation associated with CO degassing in rivers are difficult to quantify, and the consequence of CO degassing would be an overestimation of the contribution of DIC derived from the neutralization of magmatic CO by silicate rocks. [ABSTRACT FROM AUTHOR]

To explore the influence of e-book format and reading device on users' reading experience, this paper studied a group of graduate students' reading speed and comprehension. The participants were asked to read same length content from the same monograph chapter in both fixed layout format file (PDF) and fluid format file (EPUB) on four different reading devices: laptop, tablet, dedicated e-reader and smart phone. Their reading process, speed and comprehension were recorded and compared. Through the experiment and depth interviews, this study found that e-book format and reading devices have influence on reading speed and reading comprehension level. Generally speaking, people read EPUB files faster than PDF files. For smart phone, dedicated e-reader and tablet, participants' average reading comprehension is higher when reading EPUB file, while most participants read PDF file faster when they use laptops. [ABSTRACT FROM AUTHOR]

An electrochemical microsensor for chloramphenicol (CAP) was fabricated by introducing magnetic FeO nanoparticles (NPs) onto the surface of activated carbon fibers. This microsensor exhibited increased electrochemical response toward CAP because of the synergetic effect of the FeO NPs and the carbon fibers. Cyclic voltammograms were acquired and displayed three stable and irreversible redox peaks in pH 7.0 solution. Under optimized conditions, the cathodic current peaks at −0.67 V (vs. Ag/AgCl). The calibration plot is linear in the 40 pM to 1 μM CAP concentration range, with a 17 pM detection limit (at a signal-to-noise ratio of 3). The sensor was applied to the determination of CAP in spiked sediment samples. In our perception, this electrocatalytic platform provided a useful tool for fast, portable, and sensitive analysis of chloramphenicol. [ABSTRACT FROM AUTHOR]

We investigate the dynamic creation of quantum correlation and entropic uncertainty relation (EUR) in a system of two non-interacting qubits, which are initially prepared in a classically correlated state and subject to the independent radiation in an isotropic or anisotropic photonic bandgap (PBG) crystal environment. It is shown that the detuning condition and environmental structure play a crucial role in controlling the emergence of geometric quantum discord (GQD) and one-norm GQD. In addition, the remarkable similarities and differences for quantum correlation in two PBG environments are also analyzed in detail. Finally, we explore the time evolution of EUR in our model under the influence of PBG environment and present some interesting results. [ABSTRACT FROM AUTHOR]

Recently, the tensor complementarity problem has been investigated in the literature. An important question involving the property of global uniqueness and solvability for a class of tensor complementarity problems was proposed by Song and Qi (J Optim Theory Appl, 165:854-873, ). In the present paper, we give an answer to this question by constructing two counterexamples. We also show that the solution set of this class of tensor complementarity problems is nonempty and compact. In particular, we introduce a class of related structured tensors and show that the corresponding tensor complementarity problem has the property of global uniqueness and solvability. [ABSTRACT FROM AUTHOR]

Polysialic acid (PSA) is a unique polysaccharide that plays critical roles in many bioprocesses, which makes it useful in a wide range of biomedical applications. The increased demand for PSA has led to considerable efforts to improve its production using bacteria, such as Escherichia coli. Bioprocess optimization and metabolic engineering have allowed the efficient production of PSA. This review aims to summarize the metabolism of PSA with an emphasis on the importance of the key pathway components. In addition, this review provides an update on state of the art PSA production using E. coli with a special emphasis on strategies of strain engineering and process development for the enhanced production of PSA. [ABSTRACT FROM AUTHOR]

In order to evaluate the practicability of Raman spectroscopy for on-line U(VI) concentration monitoring in 30 vol.% TBP/kerosene within polyetheretherketone containers, laboratory scale experiments were performed and several influencing factors for real-time determination were investigated. A method of internal standard was employed for the first time. Software developed for real-time concentration data display can give the U(VI) concentration autonomously within several seconds. The study confirmed Raman spectroscopy as a promising methodology for on-line U(VI) concentration monitoring in organic phase. [ABSTRACT FROM AUTHOR]

The preform design is the key to bulk metal forming. An approach to optimize 3D preform shape in multi-step die forging based on quasi-equipotential field method and response surface method is employed. Firstly, optimum preforging shape is determined by means of quasi-equipotential field method and response surface optimization. Secondly, longitudinal and cross-section curve methods are introduced to design advisable blocking blank based on the optimized preforging shape. Using the method, the optimized preforging shape is determined in the hot forging of the pendulum mass. Based on the optimized preforging shape, the advisable blocking blank is constructed. The final preform design, including the advisable blocking blank and preforging shape, is completed. The desired pendulum mass forging without any defects and with smaller flash is obtained. [ABSTRACT FROM AUTHOR]

O-glycosylation-site characterization of individual glycoproteins is a major challenge because of the heterogeneity of O-glycan core structures. In proteomic studies, O-glycosylation-site analysis is even more difficult because of the complexity of the sample. In this work, we designed a rapid and convenient workflow for characterizing the O-glycosylation sites of individual proteins and the human-plasma proteome. A mixture of exoglycosidases was used to partially remove O-glycan chains and leave an N-acetylgalacosamine (GalNAc) residue attached to the Ser or Thr residues. The O-glycosylated peptides could then be identified by using liquid chromatography-tandem mass spectrometry (LC-MS-MS) to detect the 203 Da mass increase. Jacalin was used to selectively isolate O-GalNAc glycopeptides before LC-MS-MS analysis, which is optional for individual proteins and necessary for complex human-plasma proteins. Bovine fetuin and human chorionic gonadotropin (hCG) were used to test the analytical workflow. The workflow indicated superior sensitivity by not only covering most previously known O-glycosylation sites but also discovering several novel sites. Using only one drop of blood, a total of 49 O-GalNAc-linked glycopeptides from 36 distinctive glycoproteins in human plasma were identified unambiguously. The approach described herein is simple, sensitive, and global for site analysis of core 1 through core 4 O-glycosylated proteins. [ABSTRACT FROM AUTHOR]

Inflammatory damage plays a pivotal, mainly detrimental role in cerebral ischemic pathogenesis and may represent a promising target for treatment. Naringenin (NG) has gained growing appreciation for its beneficial biological effects through its anti-inflammatory property. Whether this protective effect applies to cerebral ischemic injury, we therefore investigate the potential neuroprotective role of NG and the underlying mechanisms. Focal cerebral ischemia in male Sprague-Dawley rats was induced by permanent middle cerebral artery occlusion (pMCAO) and NG was pre-administered intragastrically once daily for four consecutive days before surgery. Neurological deficit, brain water content and infarct volume were measured at 24 h after stroke. Immunohistochemistry, Western blot and RT-qPCR were used to explore the anti-inflammatory potential of NG in the regulation of NOD2, RIP2 and NF-κB in ischemic cerebral cortex. Additionally, the activities of MMP-9 and claudin-5 were analyzed to detect NG's influence on blood-brain barrier. Compared with pMCAO and Vehicle groups, NG noticeably improved neurological deficit, decreased infarct volume and edema at 24 h after ischemic insult. Consistent with these results, our data also indicated that NG significantly downregulated the expression of NOD2, RIP2, NF-κB and MMP-9, and upregulated the expression of claudin-5 ( P < 0.05). The results provided a neuroprotective profile of NG in cerebral ischemia, this effect was likely exerted by down-regulated NOD2, RIP2, NF-κB, MMP-9 and up-regulated claudin-5 expression. [ABSTRACT FROM AUTHOR]

In this work, an elastomeric FeO nano-particles (NPs)/polybutadiene rubber (BR) composite membrane was prepared by using the combined technique of electrospinning and in-situ crosslinking. The results showed that the saturation magnetization (M) and the coercive force (H) of the electrospun composite membrane with 5 wt.% FeO NPs was increased by 21 % and 69 %, respectively, comparing with the membrane prepared by solution casting. This was ascribed to the fine nano-dispersion of FeO NPs in BR matrix by using the electrospinning and in-situ crosslinking technique because the re-aggregation of FeO NPs was largely restrained by the fast evaporation of solvent, the confined space of nano/micro-sized fibers and the rapid crosslinking during electrospinning. Our work demonstrated that electrospinning and in-situ crosslinking is a simple and efficient method to improve the dispersion of nanoparticles in an elastomer matrix, and thus prepare high performance elastomeric nanocomposite. [ABSTRACT FROM AUTHOR]

Outbreaks of mass mortalities among cultured megalopa of swimming crab ( Portunus trituberculatus) occurred in a commercial hatchery during the spring of 2012 in Jiangsu province, P. R. China. Dominant bacteria were isolated and characterized by biochemical reactions, enzyme production, and sequencing analysis of the 16S rRNA, gyrB (DNA gyrase B subunit) genes, and two strains (DY1 and DY2) were selected as representative strains for virulence tests by immersion. The results showed that the characteristics of identified strains consist with Vibrio harveyi; the 16S rRNA and gyrB genes of the tested strains exhibited high similarity with V. harveyi; and the phylogenetic trees constructed using the neighbor-joining method based on 16S rRNA and gyrB genes. Two strains (DY1 and DY2) clustered with the V. harveyi and were supported by a higher bootstrap value, and two strains (DY1 and DY2) were found lethal to the healthy megalopa and juvenile crab. LD of DY1 and DY2 to megalopa and juvenile crab were 2.4 × 10, 3.0 × 10, 1.9 × 10 and 2.5 × 10 CFU/ml, respectively. The results confirmed that the diseased megalopa were infected by V. harveyi. In addition, we analyzed the tested strains (DY1 and DY2) by PCR for the presence of virulence genes that were known in V. harveyi, and the results showed that five virulence genes (luxR, toxR, vhhA, vhhB and pap6) were detected by a specific PCR assay, further supporting the assignment of isolates to V. harveyi and its pathogenicity. To our knowledge, this is the first report of V. harveyi as pathogenic bacteria of megalopa of swimming crab. [ABSTRACT FROM AUTHOR]

Dry electrical discharge machining (EDM) is an environmentally friendly modification of traditional EDM, but the material removal rate (MRR) of dry EDM is very low. A new machining method called powder mixed near dry EDM (PMND-EDM), which can improve MRR effectively, is proposed. In order to find the relationship between processing parameters and processing effect and improve processing efficiency, the MRR of PMND-EDM is studied systematically. The main processing parameters, such as peak current, pulse on time, pulse off time, powder concentration, flow rate, air pressure, and tool rotational speed, on MRR of PMND-EDM are studied in experiments. The experimental results showed that the MRR of PMND-EDM increased with the increase of peak current, pulse on time, flow rate, and air pressure, decreased with the increase of pulse off time and tool rotational speed, and increased firstly and then decreased with the increase of powder concentration. The significant test for process parameters on MRR of PMND-EDM is carried out through orthogonal design experiment. Analysis of variance for the result of orthogonal experiment indicates that peak current is significant at 99 % confidence level, pulse on time is significant at 95 % confidence level, and flow rate is significant at 90 % confidence level. Full factor experiments of peak current, pulse on time, and flow rate are conducted. The empirical formula of MRR is established based on experimental results. Its validity is demonstrated. [ABSTRACT FROM AUTHOR]

Improvement of the catalytic performance of oxygen evolution reaction (OER) is the key to the large-scale implementation of water electrolysis. Here, we report an efficient strategy to improve the OER activity of Co-based nanocomposite catalysts by adding Fe3+ ions into the electrolyte. The overpotential of cobalt tartrate annealed at 700 °C can be decreased from 360 to 329 mV by introducing 20 ppm Fe3+ into the alkaline electrolyte. Electrochemical measurements indicate that the introduction of Fe3+ can generate more efficient active sites by cooperation with Co species and promote OER kinetics, thus improving electrocatalytic performance. [ABSTRACT FROM AUTHOR]

N-Acetyl- d-neuraminic acid (Neu5Ac) has attracted considerable interest due to its promising potential applications in medicine. Significant efforts have been made in whole-cell biocatalyst for Neu5Ac production, but the processes often result in suboptimal performance due to poor expression of enzymes, imbalances of pathway components, disturbance of competing pathways, and barriers of mass transport. In this study, we engineered Escherichia coli strains capable of producing Neu5Ac by assembling a two-step heterologous pathway consisting of N-acetyl- d-glucosamine 2-epimerase (AGE) and Neu5Ac aldolase (NanA). Multiple approaches were used to improve the efficiency of the engineered pathway and process for enhanced Neu5Ac production. Firstly, we identified that NanA was the rate-controlling enzyme in this pathway. With increased expression of NanA, a ninefold increase in Neu5Ac production (65 mM) was observed. Secondly, knocking out nanTEK genes blocked Neu5Ac uptake and the competing pathway, which kept the reactions to the synthetic direction as the final product went outside of the cells and enhanced the Neu5Ac production by threefold, resulting in 173.8 mM of Neu5Ac. Thirdly, we improved the performance of the system by promoting substrate transport and optimizing concentrations of substrates. An overall whole-cell biocatalytic process was developed and a maximum titer of 240 mM Neu5Ac (74.2 g/L) was achieved, with productivity of 6.2 g Neu5Ac/L/h and conversion yield of 40 % from GlcNAc. The engineered strain could be reused for at least five cycles with a productivity of >6 g/L/h. It is a cost-effective process for Neu5Ac production with potential applications in large-scale industrial production. [ABSTRACT FROM AUTHOR]

In this study, we employed TiO enrichment and high accuracy liquid chromatography-mass spectrometry-mass spectrometry to identify the phosphoproteome of Clostridium acetobutyicum ATCC824 in acidogenesis and solventogenesis. As many as 82 phosphopeptides in 61 proteins, with 107 phosphorylated sites on serine, threonine, or tyrosine, were identified with high confidence. We detected 52 phosphopeptides from 44 proteins in acidogenesis and 70 phosphopeptides from 51 proteins in solventogenesis, respectively. Bioinformatic analysis revealed most of the phosphoproteins located in cytoplasm and participated in carbon metabolism. Based on comparison between the two stages, we found 27 stage-specific phosphorylated proteins (10 in acidogenesis and 17 in solventogenesis), some of which were solvent production-related enzymes and metabolic regulators, showed significantly different phosphorylated status. Further analysis indicated that protein phosphorylation could be involved in the shift of stages or in solvent production pathway directly. Comparison against several other organisms revealed the evolutionary diversity among them on phosphorylation level in spite of their high homology on protein sequence level. [ABSTRACT FROM AUTHOR]

The excretory-secretory products (ESP) released by muscle stage of Trichinella spiralis have been suggested to be involved in nurse cell formation. However, the molecular mechanisms by which ESP modulate nurse cell formation remain unclear. In the present study, the ability of ESP of muscle larvae of T. spiralis (ML-ESP) to influence the proliferation and differentiation of murine myoblasts and the mechanisms were evaluated in vitro using C2C12 myoblast cell line, which were incubated for various times under grow or differentiation culture medium containing various concentrations of ML-ESP. The results indicated that ML-ESP promoted myoblast proliferation in a dose-dependent manner and increased the expression of the cell-cycle regulator cyclin D1 as well as that of proliferating cell nuclear antigen (PCNA). Conversely, ML-ESP inhibited the differentiation of these cells, which was evidenced by a reduction in the levels of MHC and MRFs expression (MyoD and myogenin) as well as that of p21. In addition, ML-ESP also inhibited the phosphorylation of p38 MAPK in differentiating C2C12 myoblast. Taken together, these results imply that certain critical mediators contained in ML-ESP inhibit myogenesis through enhancing skeletal myoblasts proliferation and down-regulating the expression of MRFs as well as involving p38 MAPK signalling pathway, which provides insight into the mechanisms utilised by T. spiralis to interfere normal wound repair in infected muscle cells and affect nurse cell formation. [ABSTRACT FROM AUTHOR]

Autophagy is a highly regulated intracellular process for the degradation of cytoplasmic components, especially protein aggregates and damaged organelles. It is essential for maintaining healthy cells. Impaired or deficient autophagy is believed to cause or contribute to aging and age-related disease. In this study, we investigated the effects of age on autophagy in the kidneys of 3-, 12-, and 24-month-old Fischer 344 rats. The results revealed that autophagy-related gene (Atg)7 was significantly downregulated in kidneys of increasing age. The protein expression level of the autophagy marker light chain 3/Atg8 exhibited a marked decline in aged kidneys. The levels of p62/SQSTM1 and polyubiquitin aggregates, representing the function of autophagy and proteasomal degradation, increased in older kidneys. The level of 8-hydroxydeoxyguanosine, a marker of mitochondrial DNA oxidative damage, was also increased in older kidneys. Analysis by transmission electron microscope demonstrated swelling and disintegration of cristae in the mitochondria of aged kidneys. These results suggest that autophagic function decreases with age in the kidneys of Fischer 344 rats, and autophagy may mediate the process of kidney aging, leading to the accumulation of damaged mitochondria. [ABSTRACT FROM AUTHOR]

New 4-chalcone ursolate and 1-acetyl-3-(4-phenyl)-4,5-dihydro-2-pyrazoline-5-phenyl ursolate derivatives were synthesized by esterification of UA and chalcone or pyrazoline. The compounds were structurally confirmed by IR, H NMR, C NMR, and HR-MS spectroscopy. The cytotoxicity of ten derivatives was evaluated against A549, SKOV3, and HepG2 cell lines by MTT assay. The result showed that several compounds were more potent than UA against A549 and SKOV3 cells; however, none of them were more potent than UA against HepG2. [ABSTRACT FROM AUTHOR]

An interactive framework for soft segmentation and matting of natural images and videos is presented in this paper. The proposed technique is based on the optimal, linear time, computation of weighted geodesic distances to user-provided scribbles, from which the whole data is automatically segmented. The weights are based on spatial and/or temporal gradients, considering the statistics of the pixels scribbled by the user, without explicit optical flow or any advanced and often computationally expensive feature detectors. These could be naturally added to the proposed framework as well if desired, in the form of weights in the geodesic distances. An automatic localized refinement step follows this fast segmentation in order to further improve the results and accurately compute the corresponding matte function. Additional constraints into the distance definition permit to efficiently handle occlusions such as people or objects crossing each other in a video sequence. The presentation of the framework is complemented with numerous and diverse examples, including extraction of moving foreground from dynamic background in video, natural and 3D medical images, and comparisons with the recent literature. [ABSTRACT FROM AUTHOR]

Sintered NdFeB is widely used due to its excellent magnetic properties, but it is not suitable for machining by conventional machining methods due to its very high brittleness and hardness. Electrical discharge machining (EDM) is deemed to be an important method for machining sintered NdFeB without considering the hardness of the material. To address the problems of poor performance and high cost of EDM machining of sintered NdFeB, in this study, the effect of the EDM-milling process on the surface morphology, cross-section, material removal rate (MRR), surface roughness (SR), and electrode wear rate (EWR) of sintered NdFeB was investigated by varying parameters including current, pulse duration, and pulse interval. Comparative experiments with EDM have shown that the EDM-milling process has better performance on machined surfaces, with large craters of radial size and lower value of SR. Its cross-section has thinner recast layer and smaller range of heat-affected zone. The MRR is enhanced by a maximum of 162%. Moreover, the EWR for EDM and EDM-milling are close to zero. [ABSTRACT FROM AUTHOR]