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Force perception is one of the important research branches in human-computer interaction and compliant control of contact-rich robots. Force perception without robot end-effector sensors has attracted increasing attention in recent years, but the existing research methods do not consider the feature selection of variables in the process, and redundant dimension will increase the force perception cost of robots. To solve the above problems, we propose a new algorithm framework of Reinforcement Learning Neural Network (RLNN), which can realize the force perception of contact-rich robot. And it has the advantages of dimensionality optimization of input variables and lightweight network structure. Feature selection experiment, network structure experiment and different variable prediction experiment are conducted respectively, which proves the feasibility of our proposed algorithm framework. For force perception or prediction in robots, our research method and experimental results provide certain significance on how to balance perception dimension and perception cost. [ABSTRACT FROM AUTHOR]

Kidney renal clear cell carcinoma (KIRC) is the most common histopathologic type of renal cell carcinoma. PANoptosis, a cell death pathway that involves an interplay between pyroptosis, apoptosis and necroptosis, is associated with cancer immunity and development. However, the prognostic significance of PANoptosis in KIRC remains unclear. RNA-sequencing expression and mutational profiles from 532 KIRC samples and 72 normal samples with sufficient clinical data were retrieved from the Cancer Genome Atlas (TCGA) database. A prognostic model was constructed using differentially expressed genes (DEGs) related to PANoptosis in the TCGA cohort and was validated in a Gene Expression Omnibus (GEO) cohorts. Incorporating various clinical features, the risk model remained an independent prognostic factor in multivariate analysis, and it demonstrated superior performance compared to unsupervised clustering of the 21 PANoptosis-related genes alone. Further mutational analysis showed fewer VHL and more BAP1 alterations in the high-risk group, with alterations in both genes also associated with patient prognosis. The high-risk group was characterized by an unfavorable immune microenvironment, marked by reduced levels of CD4 + T cells and natural killer cells, but increased M2 macrophages and regulatory T cells. Finally, the risk model was predictive of response to immune checkpoint blockade, as well as sensitivity to sunitinib and paclitaxel. The PANoptosis-related risk model developed in this study enables accurate prognostic prediction in KIRC patients. Its associations with the tumor immune microenvironment and drug efficacy may offer potential therapeutic targets and inform clinical decisions. [ABSTRACT FROM AUTHOR]

Epistemic uncertainty in data-driven landslide susceptibility assessment often tends to be increased by the limited accuracy of an individual model, as well as uncertainties associated with the selection of non-landslide samples. To address these issues, this paper centers on the landslide disaster in Ji'an City, China, and proposes a heterogeneous ensemble learning method incorporating frequency ratio (FR) and semi-supervised sample expansion. Based on the superimposed results of 12 environmental factor frequency ratios (FFR), non-landslide samples were selected and input into light gradient boosting machine (LightGBM), random forest (RF), and convolutional neural network (CNN) models for prediction along with historical landslide samples. The predicted probability values are integrated by four heterogeneous ensemble strategies to expand samples from high-confidence results. The model's performance is evaluated using the area under the receiver operating characteristic curve (AUC), partition frequency ratio (PFR), and other verification methods. The results demonstrate that the negative sample based on FFR sampling is more accurate than the random sampling method, and the FR-SSELR model based on frequency ratio sampling and semi-supervised ensemble strategy exhibits the highest performance (AUC = 0.971, ACC = 0.941). A more reasonable landslide susceptibility map was drawn based on this model, with the lowest percentage of landslides in the low and very low susceptibility zones (sum of PFR = 0.194), as well as the highest percentage of landslides in the high and very high susceptibility zones (sum of PFR = 6.800). Furthermore, the FR-SSELR model improved economic benefits by 3.82–14.2%, offering valuable guidance for decision-making regarding landslide management and the sustainability of Ji'an City. [ABSTRACT FROM AUTHOR]

The friction coefficient and wear rate of pretreated graphite with liquid nitrogen were obtained by using a ball-on-disk tester, and the wear of GCr15–graphite seal pairs with the low-temperature time-dependent pretreatment was discussed by comparing the wear morphology. The results show that liquid nitrogen pretreatment can affect the hardness and interlayer spacing of graphite. The range of the friction coefficients of pretreated graphite changes from 0.17 to 0.22. With the increase of liquid nitrogen pretreatment time, the wear mechanism of graphite would change from dominated three-body wear to adhesion wear. The experimental results of the mechanical seal with liquid nitrogen pretreatment show that the wear rate of stator is less than 0.00165 mm3·N−1·m−1, and the graphite shows a good low-temperature compatibility. [ABSTRACT FROM AUTHOR]

The cadherin family plays a pivotal role in orchestrating synapse formation in the central nervous system. Cadherin-related family member 1 (CDHR1) is a photoreceptor-specific calmodulin belonging to the expansive cadherin superfamily. However, its role in traumatic brain injury (TBI) remains largely unknown. CDHR1 expression across various brain tissue sites was analyzed using the GSE104687 dataset. Employing a summary-data-based Mendelian Randomization (SMR) approach, integrated analyses were performed by amalgamating genome-wide association study abstracts from TBI with public data on expressed quantitative trait loci and DNA methylation QTL from both blood and diverse brain tissues. CDHR1 expression and localization in different brain tissues were meticulously delineated using western blotting, immunohistochemistry, and enzyme-linked immunosorbent assay. CDHR1 expression was consistently elevated in the TBI group compared to that in the sham group across multiple tissues. The inflammatory response emerged as a crucial biological mechanism, and pro-inflammatory and anti-inflammatory factors were not expressed in either group. Integrated SMR analyses encompassing both blood and brain tissues substantiated the heightened CDHR1 expression profiles, with methylation modifications emerging as potential contributing factors for increased TBI risk. This was corroborated by western blotting and immunohistochemistry, confirming augmented CDHR1 expression following TBI. This multi-omics-based genetic association study highlights the elevated TBI risk associated with CDHR1 expression coupled with putative methylation modifications. These findings provide compelling evidence for future targeted investigations and offer promising avenues for developing interventional therapies for TBI. Cadherin-related family member 1 as a potential risk factor for traumatic brain injury. [ABSTRACT FROM AUTHOR]

Accurately assessing the susceptibility of debris flow disasters is of great significance for reducing the cost of disaster prevention and mitigation, as well as disaster losses. Machine learning (ML) models have been widely used in the susceptibility assessment of debris flow disasters. However, these models often have randomness in the selection of non-disaster data, which can lead to redundant information and poor applicability and accuracy of susceptibility evaluation results. To address this issue, this paper focuses on debris flow disasters in Yongji County, Jilin Province, China; optimizes the sampling method of non-disaster datasets in machine learning susceptibility assessment; and proposes a susceptibility prediction model that couples information value (IV) with artificial neural network (ANN) and logistic regression (LR) models. A debris flow disaster susceptibility distribution map with higher accuracy was drawn based on this model. The model's performance is evaluated using the area under the receiver operating characteristic curve (AUC), information gain ratio (IGR), and typical disaster point verification methods. The results show that the rainfall and topography were found to be decisive factors in the occurrence of debris flow disasters, and the IV-ANN model established in this study had the highest accuracy (AUC = 0.968). Compared to traditional machine learning models, the coupling model produced an increase in economic benefit of about 25% while reducing the average disaster prevention and control investment cost by about 8%. Based on model's susceptibility map, this paper proposes practical disaster prevention and control suggestions that promote sustainable development in the region, such as establishing monitoring systems and information platforms to aid disaster management. [ABSTRACT FROM AUTHOR]

To improve the antibacterial properties of 304L austenitic stainless steel, copper is often added as an antibacterial agent, but the forming performance of the resulting material is poor, impacting its actual production and use. Therefore, this study investigated the influence of copper addition on the formability of 304L austenitic stainless steel with drawing, cupping and conical cup forming tests. Mechanical properties were determined with tensile and hardness tests. The microstructure and phase transformation were further characterized by metallographic microscopy, scanning electron microscopy and x-ray diffraction analysis. It was found that the addition of copper impaired the mechanical properties of 304L austenitic stainless steel, increased the stacking fault energy of the material and inhibited the occurrence of strain-induced martensite transformation, leading to a decrease in the formability of 304L austenitic stainless steel. [ABSTRACT FROM AUTHOR]

Erosion equations were developed to predict the material removal of polyurethane coatings on carbon fiber reinforced plastic (CFRP) surfaces and validated through experimental data. The effects of abrasive properties, process parameters, and organic coating properties (such as fracture toughness and hardness) were considered in the equations. As the erosion angle increased, elastoplastic deformation in the oblique direction and repeated "deformation" in the normal direction were the main reasons for material removal. The ductile erosion behavior was confirmed by experimental data because the maximum erosion rate occurred at an incident angle of 30°. The coefficient and index in the equations were determined by experimental data, and the equations were verified. The developed equations could accurately predict the quantity loss of organic coatings under different particle sizes and particle velocities, and the erosion equations were in good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

In high-speed sawing, the penetration of cutting fluid is limited due to the narrow kerf and large cutting depth. To improve the machining performance of high-speed sawing and the lubrication and cooling efficiency of cutting fluid, a technology named electrostatic minimum quantity lubrication (EMQL) high-speed sawing with water-based nanofluid as cutting fluids was developed. The adsorption and motion characteristics of droplets on the solid surface under airflow were studied. Furthermore, the machinability of EMQL in high-speed sawing was explored. The results show that the charged droplet's surface tension, static contact angle, and velocity under tangential airflow are lower than those of the uncharged droplet, while the dynamic contact angle hysteresis is higher. This indicates that the adsorbability of charged droplets on solid surface is enhanced. In high-speed sawing processing, the principal sawing force is reduced by 19% when the fluid is charged at − 4 kV. The reason may be that charging reduces the drag force of the droplet and increases the capillary force generated by the deformation of the contact line between the droplet and the solid surface, which enhances the adsorption capacity of the charged droplets on the sawtooth surfaces and improves the lubrication performance of the sawing area. [ABSTRACT FROM AUTHOR]

Robust security problem for uncertain cyber-physical systems (CPSs) subject to periodic denial-of-service (DoS) jamming attacks is investigated based on event-triggered (ET) sliding-mode control (SMC) approach in this paper. First, a new type of SMC approach driven by ET mechanism is constructed using the property of the period DoS jamming attacks. Then, sufficient conditions for robust stabilization of dynamical systems constrained by system parameters and attacks period are proposed. Further, it is proved that the execution time interval of the proposed ET-based SMC strategy has a positive lower bound, and thus Zeno-free behavior occurs during system evolution. Finally, comparisons results show the effectiveness and superiority of this methodology. [ABSTRACT FROM AUTHOR]

Nutrient reallocation The nutrient reallocation feedback mentions that if nutrients are not consumed by I Sargassum i , they would go to phytoplankton which is supposed to have lower PIC:POC ratios compared to I Sargassum i . Calcification The calcification feedback argues that CO SB 2 sb production due to the formation of carbonate shells attached to the surface of I Sargassum i can cancel most of the photosynthetic uptake of CO SB 2 sb . Since phytoplankton has similar or even higher ratios of PIC:POC, nutrient reallocation to I Sargassum i is favorable for CDR given the reasons stated above. Even if the nutrient reallocation effect is considered, the PIC compensation effect by phytoplankton is underestimated by picking a low PIC:POC ratio (0.01) for phytoplankton[11], [12]. [Extracted from the article]

Substrate damage brings great challenges to the efficient and nondestructive removal of aircraft skin coatings. Variable load erosion tests of unidirectional carbon fiber reinforced plastic along different fiber orientations were carried out. The effects of different fiber orientations on the erosion mechanism of CFRP are discussed separately. The matrix resin is squeezed and accumulated as platelets due to the erosion of the particles, and these platelets are removed due to repeated impacts of subsequent abrasives. The epoxy resin on the top layer of the laminate is penetrated by the particles with increased energy loss, and the fiber breakage is attributed to the direct impact of the particles on the carbon fiber. Fiber fractures are divided into micro-brittle fractures and macro-brittle fractures. Cracks are initiated by the concentrated stress of particle extrusion and propagate between the graphite crystallites, resulting in irregular micro-brittle fracture and fiber failure. Under the condition of macro-brittle fracture, the fiber will be debonded, flexural deformed, and even lost under the concentrated stress of particle extrusion. The purpose of this study is to provide a theoretical reference on the mechanism by which nondestructive and efficient removal of stealth coatings can be achieved on aircraft skins. [ABSTRACT FROM AUTHOR]

Cancer burden in patients aged 85 years and older has rapidly increased accompanying the decrease in mortality, which is raising the concern of developing second primary malignant neoplasms (SPM). This study aimed to investigate the epidemiology of the SPM in this population in the US by using the surveillance, epidemiology, and end results database (1975–2016). The cumulative incidence of developing a SPM was calculated by the Fine and Gray model. Standardized incidence ratios (SIR) were calculated via Poisson regression. The relative post-SPM survival rate was calculated by the Kaplan–Meier method. Male patients with skin melanoma, kidney and renal pelvis and urinary bladder cancers had high cumulative incidences (15.32%, 13.55%, and 12.26%, respectively) and increased SIRs (1.47, 1.44, and 1.16, respectively) for developing SPMs. Female patients with skin melanoma and urinary bladder cancers had high cumulative incidences (10.18% and 7.87%, respectively) and increased SIRs (1.34 and 1.18, respectively). In general, the incidence of SPM cases increased over time. The median latency ranged from 17 to 37 months. A less than 50% of patients had 1-year post-SPM survival. In conclusion, some of these patients had an increased risk of the SPM, with poor survival. [ABSTRACT FROM AUTHOR]

Medium-manganese steel is a third-generation high-strength steel for automobiles, which has the characteristics of high strength and high plasticity. The transformation-induced plasticity (TRIP) phenomenon that occurs during the straining process can improve the work hardening ability of medium-manganese steel and delay the necking phenomenon. The microstructure of 0.1C-5Mn medium-manganese steel was observed by SEM as a two-phase structure of fine-grained ferrite and retained austenite. The law of austenite transformation and strain of medium-manganese steel under uniaxial tension is obtained through magnetic method, and the retained austenite of medium-manganese steel shows a decreasing tendency with increasing strain. The functional relationship between retained austenite and equivalent strain in medium-manganese steels is derived from a dynamic model of martensitic transformation. By using the microstructure characteristics of meso-manganese steel and mesomechanical method, a meso-manganese steel constitutive model including the TRIP effect was established, and the accuracy of the method was verified by comparing it with the curves obtained from experiments and other constitutive models. The model forms the basis to simulate the behavior of medium-manganese steels. [ABSTRACT FROM AUTHOR]

Tomato is a major cultivated vegetable species of great economic importance throughout the world, but its fruit yield is severely impaired by drought stress. PopW, a harpin protein from Ralstonia solanacearum ZJ3721, plays vital roles in various plant defence responses and growth. In this study, we observed that the foliar application of PopW increased tomato drought tolerance. Our results showed that compared with water-treated plants, PopW-treated plants presented a significantly higher recovery rate and leaf relative water content under drought-stress conditions. PopW decreased the malondialdehyde content and relative electrical conductivity by 40.2% and 21%, respectively. Drought disrupts redox homeostasis through the excessive accumulation of reactive oxygen species (ROS). PopW-treated plants displayed an obvious reduction in ROS accumulation due to enhanced activities of the antioxidant enzyme catalase, superoxide dismutase and peroxidase. Moreover, PopW promoted early stomatal closure, thereby minimizing the water loss rate of plants under drought stress. Further investigation revealed that endogenous abscisic acid (ABA) levels and the transcript levels of drought-responsive genes involved in ABA signal transduction pathways increased in response to PopW. These results confirm that PopW increases drought tolerance through multiple mechanisms involving an enhanced water-retention capacity, balanced redox homeostasis, increased osmotic adjustment, reduced membrane damage and decreased stomatal aperture, suggesting that the application of exogenous PopW may be a potential method to enhance tomato drought tolerance. [ABSTRACT FROM AUTHOR]

Lead-free relaxor-ferroelectric (Mg1/3Nb2/3)4+ complex ions modified (Bi0.5Na0.5)0.94Ba0.06TiO3 (BNBT-xMN) ceramics were fabricated by traditional solid-phase reaction sintering, and the effects of (Mg1/3Nb2/3)4+ complex ions on the structural, ferroelectric, dielectric, energy storage, and strain properties of these ceramics were studied. All of the samples illustrated a single perovskite phase with a pseudo-cubic structure. Electric field-induced polarization and strain hysteresis loops indicated the occurrence of reversible ferroelectric-to-relaxor phase transition, which gave rise to a large strain of 0.49%. (Mg1/3Nb2/3)4+ complex ions greatly influenced the coercive field and remanent polarization of the ceramics; these properties also affected energy storage density of the materials. The optimal energy storage density and efficiency of the ceramics were 0.54 J/cm3 and 38.4%, respectively, when x = 0.04. These results may stem from the electric field-induced transition between the ferroelectric and relaxor-ferroelectric phase of the proposed ceramics. [ABSTRACT FROM AUTHOR]

A green manufacturing technology named "electrostatic minimum quantity lubrication (EMQL)" with water-based Al2O3 nanoparticle fluids as cutting fluids was developed in order to improve the cutting property and minimize oil mist concentration during the machining process. The capillary penetration mechanism, oil mist concentration, and heat transfer property of Al2O3 fluid EMQL were investigated. The cutting performance of Al2O3 fluid EMQL and traditional minimum quantity lubrication (MQL) was compared. The results showed that EMQL could improve the penetrability and heat transfer capacity of the lubricant effectively. Compared with Al2O3 fluid MQL and oil-based MQL, Al2O3 fluid EMQL reduced oil mist concentration and cutting temperature remarkably and showed similar cutting performances compared with the oil-based MQL. The excellent performance of this water-based Al2O3 fluid EMQL technology was mainly due to that EMQL could promote a further penetration of the charged Al2O3 nanofluid droplets into the cutting region, which thus reduced the friction force, and the tool durability was maintained obviously and finally presented better machining performance. [ABSTRACT FROM AUTHOR]

Hierarchical targeting strategy can combat the sequential drug delivery barriers by changing their properties with response to tumor stimuli. Among these strategies, much less attention has been paid to address the issues of rapid tumor clearance and insufficient cellular translocation. In this work, we demonstrate that a transactivator of transcription (TAT)-presenting nanomedicine (DATAT-NP/Pt), apart from improving tumor accumulation and cellular uptake, can simultaneously enhance tumor retention and promote nuclear translocation of encapsulated platinum prodrugs, and thus improve therapeutic efficacy. Specifically, a protecting 2,3-dimethylmaleic anhydride (DA) corona on the nanomedicine prevented the TAT peptide from serum. DATAT-NP/Pt efficiently accumulated at the tumor site through the enhanced permeability and retention (EPR) effect, followed by acid-triggered TAT presenting within the tumor acidic microenvironment (pH ~ 6.8). The exposed TAT peptide augmented tumor retention and nuclear translocation of DATAT-NP/Pt. We used a tumor-on-a-chip microfluidic system to real-time mimic and analyze tumor accumulation and retention at physiological flow conditions and revealed that surface absorption of nanomedicines on tumors was critical in determining their tumor retention and clearance. Furthermore, the TAT peptide rapidly translocated the DATAT-NP/Pt into the perinuclear region, allowing for higher nuclear platinum concentrations and increased Pt-DNA adduct formation in nuclei, which consequently reversed cisplatin resistance. Our work presents a new strategy to overcome pathophysiological barriers of tumor clearance and insufficient cellular translocation and provides new insights for the design of cancer nanomedicines. [ABSTRACT FROM AUTHOR]

This work compared the effects of sintering methods on the structure, dielectric, strain and energy storage properties of (Bi0.5Na0.5)0.94Ba0.06Ti0.965(Mg1/3Nb2/3)0.035O3 (BNBT-0.035MN) lead-free ceramics. The single phase perovskite structure of BNBT-0.035MN ceramics was independent with sintering methods. The ceramics by two-step sintering had smaller grain size and denser microstructure than those of the ceramics by traditional sintering. Compared with traditional sintering, the ceramics by two-step sintering exhibited better energy storage properties. The optimum energy storage density (W = 0.80 J/cm3) and corresponding efficiency (η = 65%) were obtained at 70 kV/cm, while the electric field-induced strain decreased. Dielectric properties of two-step sintering samples were inferior to that of traditional samples, which is related to the grain size effect. [ABSTRACT FROM AUTHOR]

Lead-free [(BiNa)Ba]LaTiO (BNBLT) ceramics for energy storage application were prepared by traditional solid-state reaction technique, and the La ions doping content was varied at 0 ≤ x ≤ 0.04. The BNBLT ceramics showed single-phase perovskite structure without impurity phase. Compact and uniform microstructure with fine grain size was obtained. The remanent polarization and coercive field decreased with the increase in La ions doping content, and the energy storage density increased drastically. The maximum energy storage density of the BNBLT ceramics at x = 0.04 was 1.09 J/cm by using LaO powders and can be further increased to 1.21 J/cm using La(NO) powders, and meanwhile, the breakdown field strength increased obviously. Anti-ferroelectric-like behavior with a double pinched P- E hysteresis loop was observed in La-doped BNBLT ceramics at room temperature, which is promising candidate for energy storage dielectric ceramic. [ABSTRACT FROM AUTHOR]

Ax21 family proteins have been shown to play regulatory roles in plant- and animal-pathogenic species in the bacterial family Xanthomonadaceae, but the protein have not been investigated previously in the non-pathogenic members of this bacterial family. Lysobacter enzymogenes, is a non-pathogenic species known for its capacity as a biocontrol agent of plant pathogens. It is also noted for the production of antimicrobial secondary metabolites, heat stable antifungal factor (HSAF) and WAP-8294A2, that have potential for agricultural and pharmaceutical applications. The species also displays type IV pili-dependent twitching motility and the production of multiple extracellular lytic enzymes as additional biocontrol-related traits. Here, we show that L. enzymogenes strain OH11 possesses three genes widely separated in the OH11 genome that code for unique Ax21-like proteins (Lsp). By comparing the wildtype OH11 with mutant strains having a single lsp gene or a combination of lsp genes deleted, we found that each Lsp protein individually is involved in positive regulation of HSAF and WAP-8294A2 biosynthesis, but the proteins collectively do not exert additive effects in this regulation. None of the Lsp proteins were found to influence twitching motility or the production of three extracellular lytic enzymes. This study is the first to provide evidence linking Ax21-family proteins to antibiotic biosynthesis and, hence, adds new insights into the diversity of regulatory functions of Ax21 family proteins in bacteria. [ABSTRACT FROM AUTHOR]

Coastal lagoons with small catchment basins are highly sensitive to natural processes and anthropogenic activities. To figure out the environmental changes of a coastal lagoon and its contribution to carbon burial, two sediment cores were collected in Xincun Lagoon, southeastern Hainan Island and Pb activities, grain size parameters, total organic carbon (TOC), total nitrogen (TN), total inorganic carbon (TIC) and stable carbon isotopes (δC) were measured. The results show that in 1770-1815, the decreasing water exchange capacity with outer open water, probably caused by the shifting and narrowing of the tidal inlet, not only diminished the currents and fined the sediments in the lagoon, but also reduced the organic matter of marine sources. From 1815 to 1950, the sedimentary environment of Xincun Lagoon was frequently influenced by storm events. These extreme events resulted in the high fluctuation of sediment grain size and sorting, as well as the great variation in contributions of terrestrial (higher plants, soils) and marine sources (phytoplankton, algae, seagrass). The extremely high content of TIC, compared to TOC before 1950 could be attributed to the large-scale coverage of coral reefs. However, with the boost of seawater aquaculture activities after 1970, the health growth of coral species was severely threatened, and corresponding production and inorganic carbon burial flux reduced. The apparent enhanced inorganic carbon burial rate after 1990 might result from the concomitant carbonate debris produced by seawater aquaculture. This result is important for local government long-term coastal management and environmental planning. [ABSTRACT FROM AUTHOR]

By far, many package cohesion metrics have been proposed from internal structure view and external usage view. Based on whether client usage context (i.e., the way packages are used by their clients) is exploited, we group these metrics into two categories: non-context-based and context-based. Currently, there is no comprehensive empirical research devoted to understanding the actual value of client usage context for fault-proneness prediction. In this study, we conduct a thorough empirical study to investigate the value of considering client usage context in package cohesion for fault-proneness prediction. First, we use principal component analysis to examine the relationships between context-based and non-context-based cohesion metrics. Second, we employ univariate logistic regression analysis to investigate the correlation between context-based cohesion metrics and fault-proneness. Then, we build multivariate prediction models to analyze the ability of context-based cohesion metrics for fault-proneness prediction when used alone or used together with non-context-based cohesion metrics. To obtain comprehensive evaluations, we evaluate the effectiveness of these multivariate models in the ranking and classification scenarios from both cross-validation and across-version perspectives. The experimental results show that (1) context-based cohesion metrics are complementary to non-context-based cohesion metrics; (2) most of context-based cohesion metrics have a significantly negative association with fault-proneness; (3) when used alone or used together with non-context-based cohesion metrics, context-based cohesion metrics can substantially improve the effectiveness of fault-proneness prediction in most studied systems under both cross-validation and across-version evaluation. Client usage context has an important value in package cohesion for fault-proneness prediction. [ABSTRACT FROM AUTHOR]

Coastal lagoon deposits provide evidence for the magnitude and frequency of past tropical cyclones prior to instrumental records and historical documentation. In the present study, we attempt to analyze the sedimentary records containing typhoon information for the northern South China Sea region. For this purpose, sediment cores were collected from two coastal lagoons in the southeastern Hainan Island, and were analyzed in laboratory to derive the data sets about grain size, organic and inorganic carbon contents, and deposition rates. The grain size and organic-inorganic carbon data were used to formulate the proxies of typhoon events. The deposition rates, as calculated using the CRS Pb method, are around 0.5 mm/a for both lagoons, on the basis of which an age model is established. Within the cores, sedimentary layers associated with 35 typhoon events have been identified. On such a basis, a 350 year history of local typhoon activities is reconstructed by incorporating the 210Pb dating results, typhoon-induced sedimentation patterns and the historical documents. A comparison of the frequency of typhoon occurrence with the regional climate records indicates that the observed changes in tropical cyclone activity patterns, as revealed by the lagoon sedimentary records, may be related to El Niño, Pacific Decadal Oscillation (PDO), North Atlantic Oscillation (NAO), sunspot, and other potential climate drivers that affect the tropical cyclone variability. This study demonstrates that the sedimentary record of storms can be analyzed in combination with historical documents, to provide meaningful information on past storm activities and their long-term variability. [ABSTRACT FROM AUTHOR]

An extracellular organic solvent-tolerant lipase-producing bacterium was isolated from oil-contaminated soil samples and was identified taxonomically as Pseudomonas stutzeri, from which the lipase was purified and exhibited maximal activity at temperature of 50 °C and pH of 9.0. Meanwhile, the lipase was stable below or at 30 °C and over an alkaline pH range (7.5-11.0). Ca could significantly improve the lipase thermal stability which prompts a promising application in biocatalysis through convenient medium engineering. The lipase demonstrated striking features such as distinct stability to the most tested hydrophilic and hydrophobic solvents (25 %, v/ v), and DMSO could activate the lipase dramatically. In the enzyme-catalyzed resolution, lipase ZS04 manifested excellent enantioselective esterification toward the ( R)-1-(4-methoxyphenyl)-ethanol (MOPE), a crucial chiral intermediate in pharmaceuticals as well as in other analogs with strict substrate specificity and theoretical highest conversion yield. This strong advantage over other related schemes made lipase ZS04 a promising biocatalyst in organic synthesis and pharmaceutical applications. [ABSTRACT FROM AUTHOR]

The field emission properties and the vacuum measurement application are investigated from the multi-walled carbon nanotubes (MWNTs) grown directly on catalytic stainless steel substrates. The MWNT emitters present excellent emission properties after the acid treatment of the substrate. The MWNT gauge is able to work down to the extreme-high vacuum (XHV) range with linear measurement performance in wide range from 10 to 10 Torr. A modulating grid is attempted with improved gauge sensitivity. The extension of the lower pressure limit is attributed largely to low outgassing effect due to direct growth of MWNTs and justified design of the electron source. [ABSTRACT FROM AUTHOR]

We study the effect of disorder on the superconductor-insulator transition in an inhomogeneous d-wave superconductor using the kernel polynomial method. As the Bogoliubov-de Gennes equations of the two-dimensional square lattice are solved self-consistently for the cases with more than 100000 unit cells, it is possible to observe the spatial fluctuations of the super-conducting order parameters at the nanoscale. We find that strong spatial fluctuation of the superconducting order parameters can be introduced by disorder, and some superconducting specific order parameters are even enhanced. Moreover, we find that some isolated superconducting 'islands' can survive the strong disorder, giving a boson insulator with some localized Cooper pairs. Our numerical calculations predict the existence of two sequential transitions with the increasing disorder strength: a d-wave to s-wave superconductor transition, and then an s-wave superconductor to insulator transition. The possibility of the appearance of a metallic phase between the superconducting and insulating phases is excluded by performing the lattice-size scaling of the generalized inverse participation ratio. In addition, we also discuss the effect of disorder on the optical conductivity of the d-wave superconductors. [ABSTRACT FROM AUTHOR]

Lysobacter enzymogenes is a bacterial biological control agent emerging as a new source of antibiotic metabolites, such as heat-stable antifungal factor (HSAF) and the antibacterial factor WAP-8294A2. The regulatory mechanism(s) for antibiotic metabolite biosynthesis remains largely unknown in L. enzymogenes. Clp, a cyclic adenosine monophosphate (cAMP)-receptor-like protein, is shown to function as a global regulator in modulating biocontrol-associated traits in L. enzymogenes. However, the genetic basis of Clp signaling remains unclear. Here, we utilized transcriptome/microarray analysis to determine the Clp regulon in L. enzymogenes. We showed that Clp is a global regulator in gene expression, as the transcription of 775 genes belonging to 19 functional groups was differentially controlled by Clp signaling. Analysis of the Clp regulon detected previously characterized Clp-modulated functions as well as novel loci. These include novel loci involved in antibiotic metabolite biosynthesis and surface motility in L. enzymogenes. We further showed experimentally that Clp signaling played a positive role in regulating the biosynthesis of HSAF and WAP-8294A2, as well as surface motility which is a type-IV-pilus-dependent trait. The regulation by Clp signaling of antibiotic (HSAF and WAP-8294A2) biosynthesis and surface motility was found to be independent. Importantly, we identified a factor Lysobacter acetyltransferase (Lat), a homologue of histone acetyltransferase Hpa2, which was regulated by Clp and involved in HSAF biosynthesis, but not associated with WAP-8294A2 production and surface motility. Overall, our study provided new insights into the regulatory role and molecular mechanism of Clp signaling in L. enzymogenes. [ABSTRACT FROM AUTHOR]

This paper investigates the H control problem for a class of uncertain switched nonlinear singular systems with time delay. By appropriately introducing some auxiliary variables and using a Lyapunov-Metzler inequality approach, some sufficient conditions for finding a suitable state-dependent switching law guaranteeing the switched system meets the desired control objective are firstly given. Then, these results are extended to construct a state feedback controller. Based on the derived results, the existence conditions of an observer-based output feedback H controller for the switched system are provided and formulated by using a combination of a linear matrix inequality (LMI) approach and a linear search algorithm. Finally, some numerical examples are performed to show the effectiveness and superiority of the proposed methods. [ABSTRACT FROM AUTHOR]

It has been reported that the heaviest rain event since 1951 hit Beijing on 21 July 2012 (henceforth referred to as the 721 case). The frequency and extreme attributes of the large-scale circulation patterns observed during the 721 case are explored by using obliquely rotated T-mode principle component analysis (PCA) and reanalysis data from NCEP/NCAR. The occurrence frequency of the 721-type circulation during the summers of 1951-2012 is 10.9%, while the frequency of torrential rain under this type of circulation is 4.51%. Relative to other rainstorms with similar large-scale circulations during the study period, the 721 case is characterized by a more westward extension of the subtropical high over the western North Pacific, a stronger low-level jet in the lower troposphere over the south of Beijing, a larger amount of ambient precipitable water, and a stronger vertical wind shear over Beijing. Among the 621 days with the 721-type circulation during the study period, the 721 case ranks the 54th in terms of the 925-hPa low-level jet south of Beijing, the 209th in terms of the local vertical wind shear, and the 8th in terms of the local precipitable water. The 721 case is particularly extreme with respect to the 925-hPa low-level jet south of Beijing and local precipitable water. Cases with similar circulations and equal or greater values of the 925-hPa low-level jet south of Beijing and local precipitable water have occurred thrice during the summers of 1951-2012 (i.e., once every 21 years). [ABSTRACT FROM AUTHOR]

In view of the low efficiency and low automation of the traditional geotechnical engineering geological survey construction quality control method, this paper puts forward the construction quality automatic control method of geotechnical engineering geological survey. The finite element model of geotechnical engineering geological investigation is established by using CRM geological model transformation method. According to the numerical analysis method, the boundary area is cut, and according to the characteristics of the geological model, the volume mesh model is generated by multi-spatial domain method, and the generated model is imported into the finite element analysis system. The finite element model of automatic control platform of full hydraulic core drilling machine is designed. The drilling pressure control method is used to control the drilling pressure in the process of measurement, and the rammed expanded pile with composite carrier is used for construction. The experimental results show that the method can establish the finite element model with high speed and precision on the basis of realizing the automatic control of the construction quality of geological survey in geotechnical engineering. The utility model has the advantages of high precision, small size, strong anti-interference ability, and low cost. [ABSTRACT FROM AUTHOR]