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High-order harmonics in solids provide a method of analyzing the intraband and interband dynamics of a solid driven by an ultrafast laser. This study analyzed the contributions of intraband and interband dynamics based on angle-resolved high-order harmonics. According to the simulations and experiments, we found that the angular divergences of the harmonics have an evident boundary at the bandgap when the laser is polarized along the asymmetric direction, which is primarily invoked by the interplay of an interband transition and an intraband electron movement, and the intraband and interband dynamics have different sensitivities of the spatial phase of driving laser. [ABSTRACT FROM AUTHOR]

By applying ultrasonic treatment to ZL205A aluminum alloy melt containing different Cd contents and then using a tensile test, a scanning electron microscope experiment, and a metallographic experiment, the influence of ultrasonic treatment to ZL205A aluminum alloy melt on the properties of aluminum–copper alloy with different Cd contents in the liquid phase high-temperature region was studied. The effect of ultrasonic treatment on the solidification structure of ZL205A aluminum alloy was investigated. The results showed that there was no significant difference in the form of Cd and the solid solution rate of the aluminum alloy with different Cd contents in ultrasonic-assisted casting. However, the effect of ultrasonic waves on the high-temperature liquid phase of the melt of ZL205A aluminum alloy can effectively reduce the porosity defects in the solidification structure of the casting, refine the solidification structure, and make the structure more uniform. The ultrasonic cavitation effect can promote the formation and uniform distribution of Al–3Ti and improve the nucleation rate, and the effect can continue after heat treatment. This can solve the problem that increasing Cd content in ZL205A greatly reduces the toughness of castings while increasing the strength. The sample with a Cd content of 0.20% and with ultrasonic treatment has the highest strength, the average tensile strength is 475.5 MPa, and the yield strength is 381.75 MPa. However, compared with the conventional casting samples with the same Cd content, the decrease in elongation was significantly reduced. [ABSTRACT FROM AUTHOR]

Background and objectives: Local anesthetics (LAs) are widely used to infiltrate into surgical wounds for postoperative analgesia. Different adjuvants like dexamethasone and dexmedetomidine, when added to LA agents, could improve and prolong analgesia. The aim of this trial was to evaluate the analgesic efficacy and opioid-sparing properties of dexamethasone and dexmedetomidine when added to ropivacaine for wound infiltration in transforaminal lumbar interbody fusion (TLIF). Methods: We conducted a controlled study among 68 adult patients undergoing TLIF, which was prospective, randomized and double-blind in nature. The participants were divided into four equal groups at random. Group R was given 150 mg of 1% ropivacaine (15 mL) and 15 mL of normal saline. Group R + DXM received 150 mg of 1% ropivacaine (15 mL) and 10 mg of dexamethasone (15 mL). Group R + DEX received 150 mg of 1% ropivacaine (15 mL) and 1 µg/kg of dexmedetomidine (15 mL). Lastly, group R + DXM + DEX was given 150 mg of 1% ropivacaine (15 mL), 10 mg of dexamethasone and 1 µg/kg of dexmedetomidine (15 mL). The primary focus was on the length of pain relief provided. Additionally, secondary evaluations included the amount of hydromorphone taken after surgery, the numerical rating scale and safety assessments within 48 h after the operation. Results: Based on the p value (P > 0.05), there was no significant variance in the duration of pain relief or the total usage of hydromorphone after surgery across the four groups. Similarly, the numerical rating scale scores at rest and during activity at 6-, 12-, 24- and 48-h post-surgery for all four groups showed no difference (P > 0.05). However, the incidence of delayed anesthesia recovery was slightly higher in group R + DEX and group R + DXM + DEX when compared to group R or group R + DXM. Furthermore, there were no significant differences between the four groups in terms of vomiting, nausea, dizziness or delayed anesthesia recovery. Conclusion: For wound infiltration in TLIF, the addition of dexamethasone and dexmedetomidine to ropivacaine did not result in any clinically significant reduction in pain or opioid consumption and could prompt some side effects. [ABSTRACT FROM AUTHOR]

A facile and general strategy for preparing carbon supports with ideal sintering resistance using electrospinning and sulfidation treatment is reported in this paper. The strong interaction between PtCu and N,S-codoped electrospinning porous carbon nanofibers can stabilize PtCu nanoparticles (NPs) below 4 nm to 800 °C. The as-prepared PtCu-800/NS-PCNFs exhibit superior catalytic performances for oxygen reduction reaction (ORR). The PtCu-800/NS-PCNFs presents the mass activity (MA) and specific activity (SA) of 0.4785 A mg−1 and 0.6343 mA cm−2, which is 3.1 times and 2.4 times that of commercial Pt/C. More important, the electrochemical surface area (ECSA) of PtCu-800/NS-PCNFs is 1.3 times larger than that of commercial Pt/C. Therefore, the improved ORR activity can be ascribed to the synergistic interaction between Pt and Cu and the uniform distribution of catalyst nanoparticles. • NS-PCNFs with high specific surface area were prepared by electrospinning and sulfidation treatment. • The strong interaction between PtCu and NS-PCNFs can stabilize PtCu NPs during the high-temperature reduction process. • The PtCu nanoparticles were loaded on NS-PCNFs by the impregnation-reduction method. • The PtCu-800/NS-PCNFs showed an efficient activity in the ORR compared with the commercial Pt/C. [ABSTRACT FROM AUTHOR]

Background and objectives: Local anesthetics (LAs) are widely used to infiltrate into surgical wounds for postoperative analgesia. Different adjuvants like dexamethasone and dexmedetomidine, when added to LA agents, could improve and prolong analgesia. The aim of this trial was to evaluate the analgesic efficacy and opioid-sparing properties of dexamethasone and dexmedetomidine when added to ropivacaine for wound infiltration in transforaminal lumbar interbody fusion (TLIF). Methods: We conducted a controlled study among 68 adult patients undergoing TLIF, which was prospective, randomized and double-blind in nature. The participants were divided into four equal groups at random. Group R was given 150 mg of 1% ropivacaine (15 mL) and 15 mL of normal saline. Group R + DXM received 150 mg of 1% ropivacaine (15 mL) and 10 mg of dexamethasone (15 mL). Group R + DEX received 150 mg of 1% ropivacaine (15 mL) and 1 µg/kg of dexmedetomidine (15 mL). Lastly, group R + DXM + DEX was given 150 mg of 1% ropivacaine (15 mL), 10 mg of dexamethasone and 1 µg/kg of dexmedetomidine (15 mL). The primary focus was on the length of pain relief provided. Additionally, secondary evaluations included the amount of hydromorphone taken after surgery, the numerical rating scale and safety assessments within 48 h after the operation. Results: Based on the p value (P > 0.05), there was no significant variance in the duration of pain relief or the total usage of hydromorphone after surgery across the four groups. Similarly, the numerical rating scale scores at rest and during activity at 6-, 12-, 24- and 48-h post-surgery for all four groups showed no difference (P > 0.05). However, the incidence of delayed anesthesia recovery was slightly higher in group R + DEX and group R + DXM + DEX when compared to group R or group R + DXM. Furthermore, there were no significant differences between the four groups in terms of vomiting, nausea, dizziness or delayed anesthesia recovery. Conclusion: For wound infiltration in TLIF, the addition of dexamethasone and dexmedetomidine to ropivacaine did not result in any clinically significant reduction in pain or opioid consumption and could prompt some side effects. [ABSTRACT FROM AUTHOR]

Composite bipolar plates (BPs) hinder their application in proton exchange membrane fuel cells (PEMFC) because of their poor conductivity and mechanical properties. Nanofillers can effectively solve this problem but often have a limited effect due to their easy agglomeration. In this work, a continuous mesh carboxylated multi-walled carbon nanotube (MWCNT) coating on the surface of graphite was synthesized by chemical vapor deposition (CVD) and carboxylation modification, and the composite BPs were prepared by molding using prepared reticulated carboxylated MWCNTs, expanded graphite, and resin. By optimizing the carboxylation treatment time and the content of the nano-filler, the composite BPs had the best performance at a 15 min carboxylation treatment time and 2.4% filler content. The planar conductivity reached up to 243.52 S/cm, while the flexural strength increased to 61.9 MPa. The thermal conductivity and hydrophobicity were improved compared with the conventional graphite/resin composite BPs, and good corrosion resistance has been demonstrated under the PEMFC operating environment. This work provides a novel nanofiller modification paradigm for PBs. [ABSTRACT FROM AUTHOR]

Based on ZnO, Ag nanoparticles (NPs) and porous silicon (PS), ZnO/Ag/PS sandwich structures with different Ag nanostructures including Ag NP array, Ag NP dimer array, Ag cone array, and Ag cone dimer array are constructed using wave optics module of Comsol Multiphysics. Under S-polarization and P-polarization, the effect of different Ag nanostructures on electric field distribution, absorption, and fluorescence emission of the sandwich structures is investigated. Results indicate that compared with the sandwich structures with Ag NP array, the fluorescence emission of that with Ag NP dimer array is greatly enhanced. The fluorescence intensity under S-polarization is different from that under P-polarization, but the peak positions are same. Finally, the electron transport mechanism in the sandwich structures is proposed. We discuss the electron transfer, the resonance peak positions of different Ag nanostructures and the overlapping area between ZnO and Ag to further confirm the fluorescence emission mechanism. It provides a new design idea for highly efficient optoelectronic devices. [ABSTRACT FROM AUTHOR]

Composite bipolar plates with excellent performance play a crucial role in improving the overall performance of proton-exchange-membrane fuel cells. However, for graphite/resin composite bipolar plates, their electrical conductivity and mechanical properties are often too complex to meet the needs of users at the same time. Although nanoconductive fillers can alleviate this problem, the performance improvement for composite bipolar plates is often limited due to problems such as agglomeration. In this study, a uniformly dispersed multi-walled carbon nanotube network was prepared by in situ vapor deposition on the surface and pores of expanded graphite, which effectively avoided the problem of agglomeration and effectively improved the various properties of the composite BPs through the synergistic effect with graphite. With the addition of 2% in situ deposited carbon nanotubes, the modified composite bipolar plate has the best conductivity (334.53 S/cm) and flexural strength (50.24 MPa), and all the properties can meet the DOE requirements in 2025. Using the in situ deposition of carbon nanotubes to modify composite bipolar plates is a feasible route because it can result in multi-walled carbon nanotubes in large quantities and avoid the agglomeration phenomenon caused by adding nanofillers. It can also significantly improve the performance of composite bipolar plates, achieving the high performance of composite bipolar plates at a lower cost. [ABSTRACT FROM AUTHOR]

Polyploids are cells or organisms with a genome consisting of more than two sets of homologous chromosomes. Polyploid plants have important traits that facilitate speciation and are thus often model systems for evolutionary, molecular ecology and agricultural studies. However, due to their unusual mode of inheritance and double‐reduction, diploid models of population genetic analysis cannot properly be applied to autopolyploids. To overcome this problem, we developed a software package entitled vcfpop to perform a variety of population genetic analyses for autopolyploids, such as parentage analysis, analysis of molecular variance, principal coordinates analysis, hierarchical clustering analysis and Bayesian clustering. We used three data sets to evaluate the capability of vcfpop to analyse large data sets on a desktop computer. This software is freely available at http://github.com/huangkang1987/vcfpop. [ABSTRACT FROM AUTHOR]

The forecast skill for week-2 wintertime surface air temperature (SAT) over the Northern Hemisphere by the Model for Prediction Across Scales–Atmosphere (MPAS-A) is evaluated and compared with operational forecast systems that participate in the Subseasonal to Seasonal Prediction project (S2S). An intercomparison of the MPAS against the China Meteorological Administration (CMA) model and the European Centre for Medium-Range Weather Forecasts (ECMWF) model was performed using 10-yr reforecasts. Comparing the forecast skill for SAT and atmospheric circulation anomalies at a lead of 2 weeks among the three models, the MPAS shows skill lower than the ECMWF model but higher than the CMA model. The gap in skills between the MPAS model and CMA model is not as large as that between the ECMWF model and MPAS model. Additionally, an intercomparison of the MPAS model against 10 S2S models is presented by using real-time forecasts since 2016 stored in the S2S database. The results show that the MPAS model has forecast skill for week-2 to week-4 wintertime SAT comparable to that in most S2S models. The MPAS model tends to be at an intermediate level compared to current operational forecast models. [ABSTRACT FROM AUTHOR]

Perfluorooctanoic acid (PFOA) as emerging pollutants was largely produced and stable in nature environment. Its fate and effect to the wasted sludge digestion process and corresponding microbial mechanism was rarely reported. This study investigated the different dose of PFOA to the wasted sludge digestion process, where the methane yield and microbial mechanism was illustrated. The PFOA added before digestion were 0–10000 μg/L, no significant variation in daily and accumulated methane production between each group. The 9th day methane yield was significantly higher than other days (p < 0.05). The soluble protein was significantly decreased after 76 days digestion (p < 0.001). The total PFOA in sludge (R2 = 0.8817) and liquid (R2 = 0.9083) phase after digestion was exponentially correlated with PFOA dosed. The PFOA in liquid phase was occupied 54.10 ± 18.38% of the total PFOA in all reactors. The dewatering rate was keep decreasing with the increase of PFOA added (R2 = 0.7748, p < 0.001). The mcrA abundance was significantly correlated with the pH value and organic matter concentration in the reactors. Chloroflexi was the predominant phyla, Aminicenantales , Bellilinea and Candidatus_Cloacimonas were predominant genera in all reactors. Candidatus_Methanofastidiosum and Methanolinea were predominant archaea in all reactors. The function prediction by FAPROTAX and Tax4fun implied that various PFOA dosage resulted in significant function variation. The fermentation and anaerobic chemoheterotrophy function were improved with the PFOA dose. Co-occurrence network implied the potent cooperation among the organic matter degradation and methanogenic microbe in the digestion system. PFOA has little impact to the methane generation while affect the microbe function significantly, its remaining in the digested sludge should be concerned to reduce its potential environmental risks. • The methane production has a highest value on the 9th day digestion. • There were no significant variations in methane production with PFOA up to 10 mg/L. • The sludge dewatering rate was keep decreasing with the increase of PFOA dose. • The mcrA abundance was significantly correlated with pH value. [ABSTRACT FROM AUTHOR]

Na superionic conductor-type Na1+xZr2SixP3-xO12 (0 ≤ x ≤ 3, NZSPO) is considered as one of the most promising solid electrolytes for solid-state sodium batteries, while its relatively low ionic conductivity of 10−4 S cm−1 requires improvement for application. In this study, a synergetic strategy is applied to improve the ionic conductivity of NZSPO, i.e., by combining bulk doping and grain-boundary engineering. Hf4+ is selected as the substitution for Zr4+ to stabilize the highly conducting rhombohedral phase. La2O3 is added as a sintering aid to promote the ion transport along the grain boundaries with Na3La(PO4)2 formed therein. The optimized Na3Zr1.8Hf0.2Si2PO12-Na3La(PO4)2 (NZHSPO-NLPO) ceramic electrolytes show a high relative density of 98.8% and the superior ionic conductivity of 1.66 × 10−3 S cm−1 at 30 °C. The Na symmetric batteries display the stable plating/stripping cycling over 500 h at 0.1 mA cm−2 and 0.05 mAh cm−2. With ionic liquid as a wetting agent at cathode sides and PEO as an intermediate layer at anode sides, the NZHSPO-NLPO-based Na batteries with Na3V2(PO4)3 cathodes exhibit the discharge capacity of 109.9 mAh g−1 and capacity retention of 92.7% at 0.1 and 30 °C for 50 cycles. It is proved that the simultaneous optimization of bulk and grain boundaries is powerful for increasing the ionic conductivity of ceramic solid electrolytes. [ABSTRACT FROM AUTHOR]

In this study, a highly conductive composite bipolar plate with an embedded conductive carbon nanofiber network was prepared by chemical vapor deposition, and a conductive network was constructed inside the composite bipolar plate. The latter network was then compared with a conductive network formed by directly adding carbon nanotubes more evenly distributed. The optimum preparation methods of vapor-grown carbon fibers and the fiber content were analyzed, and the specific surface area and porosity of the bipolar plates were measured and analyzed using a BET test. The results show that the carbon nanofibers prepared under the conditions of 700 °C and a content of 2% exhibited the best effect on improving the performance of the bipolar plates. The conductivity of the prepared bipolar plates could reach 255.2 S/cm, which is 22.1% higher than treatment with multi-walled carbon nanotubes. The bending strength of the prepared bipolar plates was 47.92 MPa, and the interface contact resistance was 6.24 mΩ·cm2. In conclusion, the bipolar plates modified with vapor-grown carbon fibers were a promising kind of material for proton exchange membrane fuel cells. [ABSTRACT FROM AUTHOR]

Truck-wash facilities have become popularized globally on construction sites, and the wastewater was frequently treated by three-stage sedimentation basins. The wastewater and bacterial characteristics in three-stage sedimentation basins need to be studied, which might affect the treatment cost and reuse security. In this study, the wastewater characteristics, bacterial communities, and pathogenic bacteria distribution of three-stage sedimentation basins on four construction sites were investigated. Results indicated that truck-wash wastewater contained a high concentration of suspended solids (29–211 mg/L) and bacteria (4.2×103 to 2.7×104 colony forming units/mL). Proteobacteria (mean at 72.3%), Firmicutes (mean at 11.3%), and Bacteroidetes (mean at 10.6%) were the predominant bacterial phyla and Acinetobacter (mean at 18.4%), Chryseomicrobium (mean at 6.3%), and Paracoccus (mean at 6.1%) were the predominant bacterial genera. Truck-wash wastewater contained pathogenic bacteria, identified by the Illumina sequencing method. Acinetobacter, Shigella, or Escherichia (about 0.2%) and Legionella (about 0.2%) were the main pathogenic bacteria and Legionella should be a concern due to the wastewater reuse method. Traditional three-stage sedimentation basins should be simplified and further improved because of the lower suspended solids or pathogenic bacteria removal effect. The practical technology for suspended solids and pathogenic bacteria control in truck-wash wastewater should be further studied, and disinfection facilities should be applied to protect construction workers. [ABSTRACT FROM AUTHOR]

Triple-negative breast cancer (TNBC) is a unique breast cancer subtype characterized by a lack of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) expression. Since TNBC lacks ER, PR, and HER2, there are currently no drugs that specifically target TNBC. Therefore, the development of new drugs or effective treatment strategies to target TNBC has become an urgent clinical need. Research has shown that the application of histone deacetylase (HDAC) inhibitors and DNA methyltransferase (DNMT) inhibitors leads to genomic and epigenomic instability. This, in turn, triggers the activation of pattern recognition receptors (PRRs) and subsequently activates downstream interferon (IFN) signalling pathways. In this study, the bifunctional HDAC and DNMT inhibitor J208 exhibited antitumour activity in TNBC cell lines. J208 effectively induced apoptosis and cell cycle arrest at the G0/G1 phase, inhibiting cell migration and invasion in TNBC. Moreover, this bifunctional inhibitor induced the expression of endogenous retroviruses (ERVs) and elicited a viral mimicry response, which increased the intracellular levels of double-stranded RNA (dsRNA) to activate the innate immune signalling pathway in TNBC. In summary, we demonstrated that the bifunctional inhibitor J208, which is designed to inhibit HDAC and DNMT, has potent anticancer effects, providing a new research basis for reactivating antitumour immunity by triggering innate immune signalling and offering a promising strategy for TNBC treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

The receiver operating characteristic (ROC) and precision–recall (PR) plots have been widely used to evaluate the performance of species distribution models. Plotting the ROC/PR curves requires a traditional test set with both presence and absence data (namely PA approach), but species absence data are usually not available in reality. Plotting the ROC/PR curves from presence‐only data while treating background data as pseudo absence data (namely PO approach) may provide misleading results.In this study, we propose a new approach to calibrate the ROC/PR curves from presence and background data with user‐provided information on a constant c, namely PB approach. Here, c defines the probability that species occurrence is detected (labeled), and an estimate of c can also be derived from the PB‐based ROC/PR plots given that a model with good ability of discrimination is available. We used five virtual species and a real aerial photography to test the effectiveness of the proposed PB‐based ROC/PR plots. Different models (or classifiers) were trained from presence and background data with various sample sizes. The ROC/PR curves plotted by PA approach were used to benchmark the curves plotted by PO and PB approaches.Experimental results show that the curves and areas under curves by PB approach are more similar to that by PA approach as compared with PO approach. The PB‐based ROC/PR plots also provide highly accurate estimations of c in our experiment.We conclude that the proposed PB‐based ROC/PR plots can provide valuable complements to the existing model assessment methods, and they also provide an additional way to estimate the constant c (or species prevalence) from presence and background data. [ABSTRACT FROM AUTHOR]

The advancement of mid‐infrared (MIR) parametric amplification technique serves as the main driving force of multiple strong‐field experiments in the frontier of science such as the generation of coherent soft X‐ray and isolated attosecond pulses. However, the low parametric down‐conversion efficiency especially in the MIR wavelength is a major bottleneck that hinders the further exploration of the MIR‐laser‐driven strong‐field physics. Here, a simple and robust method that doubles the efficiency of a MIR optical parametric chirped‐pulse amplifier (OPCPA) is reported, as a demonstration of the concept, through engineering a flat‐top pump profile via high‐efficiency diffractive optical elements. With the proposed flat‐top pump scheme, a MIR OPCPA system at 3 μm and 10 kHz repetition rate with both the record pulse energy of 2.7 mJ and the highest average power at 27 W among the MIR OPCPAs with kHz repetition rate is demonstrated. This work provides a promising approach for achieving high energy high power MIR few‐cycle lasers that can be readily used in emerging strong field experiments. In addition, it is believed that the developed technique in this work can become a general method of parametric efficiency enhancement, which is applicable to other nonlinear conversions and wavelength ranges. [ABSTRACT FROM AUTHOR]

The European Commission recently released its proposal for a Regulation giving rise to a European Health Data Space (EHDS), as the first domain-specific common European data space under the European Union's data strategy. The proposed EHDS aims to improve access to and control by individuals of their personal electronic health data in primary use and increase data availability for secondary use purposes. This article is primarily concerned with the ambition to enhance the right of natural persons to data portability and promote interoperability in the health sector. This article seeks to delineate to what extent they represent a new and expanded right alongside the right to data portability provided in the General Data Protection Regulation (GDPR). In comparing this new expanded right to the original right outlined in Article 20 of the GDPR, the authors argue that Article 3(8) of the EHDS proposal represents an important expansion with the potential to allow individuals more possibility to control and mobilise their electronic health data, especially those elements located within Electronic Health Records (EHRs). This will also be facilitated by the strengthened interoperability requirements foreseen by the EHDS proposal. However, this paper also identifies several limitations and inconsistencies in the new data portability right which could potentially hinder its functioning. This notably includes the proposal's failure to take into account the need for data portability for secondary use purposes, and the unclear relationship of Article 3(8) of the proposal with Article 9 of the GDPR. It is recommended that these points should be considered carefully in future versions of the EHDS proposal. [ABSTRACT FROM AUTHOR]

The intracellular pathway of Janus kinase/signal transducer and activator of transcription (JAK/STAT) and modification of nucleosome histone marks regulate the expression of proinflammatory mediators, playing an essential role in carcinogenesis, antiviral immunity and the interaction of host proteins with Herpesviral particles. The pathway has also been suggested to play a vital role in the clinical course of the acute infection caused by severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2; known as coronavirus infection-2019), a novel human coronavirus initially identified in the central Chinese city Wuhan towards the end of 2019, which evolved into a pandemic affecting nearly two million people worldwide. The infection mainly manifests as fever, cough, myalgia and pulmonary involvement, while it also attacks multiple viscera, such as the liver. The pathogenesis is characterized by a cytokine storm, with an overproduction of proinflammatory mediators. Innate and adaptive host immunity against the viral pathogen is exerted by various effectors and is regulated by different signaling pathways notably the JAK/STAT. The elucidation of the underlying mechanism of the regulation of mediating factors expressed in the viral infection would assist diagnosis and antiviral targeting therapy, which will help overcome the infection caused by SARS-CoV-2. [ABSTRACT FROM AUTHOR]

Tibetan Plateau snow cover (TPSC) has subseasonal variations and rapidly influences the atmosphere. In this study, we present the rapid response of the East Asian trough (EAT) within a week to subseasonal variations in TPSC during the boreal winter. Using snow cover analysis obtained from the daily interactive multisensor snow and ice mapping system and the ERA‐Interim reanalysis, a considerable relationship between TPSC and 500‐hPa geopotential height anomalies over the downstream EAT region is found. Significant negative (positive) 500‐hPa geopotential height anomalies originating from the Tibetan Plateau and moving into the EAT region appear within a week following anomalous positive (negative) TPSC events, which lead to changes in EAT strength. Thus, a significantly enhanced (reduced) intensity of the EAT occurs approximately 5–6 days after increased (decreased) TPSC. Numerical experiments confirm the causality of this relationship. Further analysis of the quasi‐geostrophic geopotential height tendency equations in numerical experiments indicates that such EAT variations result from anomalous thermal advection from the Tibetan Plateau forced by TPSC. [ABSTRACT FROM AUTHOR]

Encounter risk prediction is critical for safe ship navigation, especially in congested waters, where ships sail very near to each other during various encounter situations. Prior studies on the risk of ship collisions were unable to address the uncertainty of the encounter process when ignoring the complex motions constituting the dynamic ship encounter behavior, which may seriously affect the risk prediction performance. To fill this gap, a novel AIS data-driven approach is proposed for ship encounter risk prediction by modeling intership behavior patterns. In particular, multidimensional features of intership behaviors are extracted from the AIS trace data to capture spatial dependencies between encountering ships. Then, the challenging task of risk prediction is to discover the complex and uncertain relationship between intership behaviors and future collision risk. To address this issue, we propose a deep learning framework. To represent the temporal dynamics of the encounter process, we use the sliding window technique to generate the sequences of behavioral features. The collision risk level at a future time is taken as the class label of the sequence. Then, the long short-term memory network, which has a strong ability to model temporal dependency and complex patterns, is extended to establish the relationship. The benefit of our approach is that it transforms the complex problem for risk prediction into a time series classification task, which makes collision risk prediction reliable and easier to implement. Experiments were conducted on a set of naturalistic data from various encounter scenarios in the South Channel of the Yangtze River Estuary. The results show that the proposed data-driven approach can predict future collision risk with high accuracy and efficiency. The approach is expected to be applied for the early prediction of encountering ships and as decision support to improve navigation safety. [ABSTRACT FROM AUTHOR]

Accurate subseasonal-to-seasonal (S2S) atmospheric forecasts and hydrological forecasts have considerable socioeconomic value. This study conducts a multimodel comparison of the Tibetan Plateau snow cover (TPSC) prediction skill using three models (ECMWF, NCEP and CMA) selected from the S2S project database to understand their performance in capturing TPSC variability during wintertime. S2S models can skillfully forecast TPSC within a lead time of 2 weeks but show limited skill beyond 3 weeks. Compared with the observational snow cover analysis, all three models tend to overestimate the area of TPSC. Another remarkable issue regarding the TPSC forecast is the increasing TPSC with forecast lead time, which further increases the systematic positive biases of TPSC in the S2S models at longer forecast lead times. All three S2S models consistently exaggerate the precipitation over the Tibetan Plateau. The exaggeration of precipitation is prominent and always exists throughout the model integration. Systematic bias of TPSC therefore occurs and accumulates with the model integration time. Such systematic biases of TPSC influence the forecasted surface air temperature in the S2S models. The surface air temperature over the Tibetan Plateau becomes colder with increasing forecast lead time in the S2S models. Numerical experiments further confirm the causality. [ABSTRACT FROM AUTHOR]

Using the daily snow cover data at 24‐km resolution from the Interactive Multi‐sensor Snow and Ice Mapping System snow cover analysis, this study describes the variability in Tibetan Plateau (TP) snow cover (TPSC) at multiple time scales with a focus on the intraseasonal time scale (10–90 days). TPSC demonstrates variability over a wide range of temporal scales, but the annual cycle is generally dominant. Synoptic‐scale variability, seasonal variability and interannual and long‐term changes make small contributions to the total daily variability in TPSC. Intraseasonal variability (ISV) is dominant over most of the central and eastern TP and explains 22–40% of the total variability and leads to obvious variations in TPSC over periods shorter than a season. The ISV of TPSC is more active in the cold season than in the warm season. Specifically, the ISV over the Changtang Plateau explains approximately 50% of the total variability of snow cover in the cold season and is even more dominant than the annual cycle. Possible influences of regional atmospheric circulations on TPSC are also examined. TPSC variability is highly correlated with regional surface air temperature (SAT) and precipitation at an intraseasonal time scale. TPSC and SAT tend to have a simultaneous relationship, while anomalous precipitation leads to subsequent TPSC variations with a lag of approximately 5 days and a positive relationship. Such relationships are the result of intraseasonal variations in regional atmospheric circulation. The anomalous adiabatic heating induced by vertical ascending motion leads to tropospheric temperature variations. Furthermore, the horizontal advection of moisture and apparent moisture sink, which are induced by anomalous moisture supply and snow evaporation anomalies, respectively, lead to anomalous moisture associated with changes in the TPSC. [ABSTRACT FROM AUTHOR]

Small diameter gravity sewers (SDGS) are extensively used to collect rural sewage as they are low in cost and quick to construct. However, the characteristics of biofilms in rural SDGS are still not clear. In this study, biofilms characteristics of aerobic rural SDGS were investigated using simulations in a lab under different flow conditions and slopes. Results indicated that the average thickness of aerobic rural SDGS biofilms was in the range of 350–650 μm, decreasing at locations with variable flow and high slopes. Protein was the most abundant substance in extracellular polymeric substance of SDGS biofilms. The most abundant bacteria, Proteobacteria , Actinobacteria , and Bacteroidetes , and functional bacteria showed different distributions when analyzed through Illumina HiSeq sequencing of 16S rRNA. The relative abundances of denitrifying bacteria, nitrite-oxidizing bacteria, and sulfate-reducing bacteria (SRB) were lower during variable flow than during stable flow. High slopes (15‰) decreased SRB presence, which could be used to mitigate H 2 S accumulation in aerobic SDGS. Overall, this study describes the characteristics of aerobic rural SDGS biofilms and provides valuable suggestions for the optimal design of SDGS based on these characteristics. Image 1 [ABSTRACT FROM AUTHOR]

Genes that are thought to be critical for the survival of organisms or cells are called essential genes. The prediction of essential genes and their products (essential proteins) is of great value in exploring the mechanism of complex diseases, the study of the minimal required genome for living cells and the development of new drug targets. As laboratory methods are often complicated, costly and time-consuming, a great many of computational methods have been proposed to identify essential genes/proteins from the perspective of the network level with the in-depth understanding of network biology and the rapid development of biotechnologies. Through analyzing the topological characteristics of essential genes/proteins in protein–protein interaction networks (PINs), integrating biological information and considering the dynamic features of PINs, network-based methods have been proved to be effective in the identification of essential genes/proteins. In this paper, we survey the advanced methods for network-based prediction of essential genes/proteins and present the challenges and directions for future research. [ABSTRACT FROM AUTHOR]

Background: Imbalance in bone formation and resorption is a crucial component of the pathological process leading to osteoporosis. Electromagnetic fields (EMFs) have been reported to be beneficial to osteogenesis, although the exact mechanism has not been fully clarified. Purinergic receptor P2X7 is expressed in osteoblasts and is reported to participate in the regulation of bone metabolism. Objectives: To elucidate the link between EMFs and P2X7 expression and investigate its potential as a novel therapeutic target in osteoporosis. Method: We investigated the effect of EMFs on P2X7 expression and downstream signaling in human bone marrow mesenchymal stem cells (h-MSCs). We also established an ovariectomized (OVX) osteoporosis rat model to evaluate the therapeutic efficacy of combining EMFs with P2X7 agonists. Results: EMF treatment increased P2X7 expression in h-MSCs under conditions of osteogenic induction but not under regular culture conditions. P2X7 or PI3K/Akt inhibition partially inhibited the pro-osteogenic effect of EMF and lowered the EMF-stimulated activity of the Akt/GSK3β/β-catenin axis. No additive effect of this suppression was observed following simultaneous inhibition of P2X7 and PI3K/Akt. EMF treatment in the presence of a P2X7 agonist had a greater effect in increasing osteogenic marker expression than that of EMF treatment alone. In the OVX osteoporosis model, the therapeutic efficacy of combining EMFs with P2X7 agonists was superior to that of EMF treatment alone. Conclusions: EMF treatment increases P2X7 expression by h-MSCs during osteogenic differentiation, leading to activation of the Akt/GSK3β/β-catenin axis, which promotes the osteogenesis. Our findings also indicate that combined EMF and P2X7 agonist treatment may be an effective novel strategy for osteoporosis therapy. [ABSTRACT FROM AUTHOR]

Bacteria in rural sewage collection systems have the important influences on operation and maintenance risks, such as sedimentation blockage and harmful gas accumulation, and pollutant pre-treatment ability. It is necessary to analyze and interpret the influence on bacterial communities caused by the location (sewage, biofilms, and deposits), season (winter and spring, summer and autumn), and system type (sewers and ditches) to better understand the bacterial characteristics in rural sewage collection systems. To achieve the above purpose, 96 samples obtained from practical rural sewage collection systems in eight villages were analyzed by 16S rRNA whole region sequencing methods. The results indicate that locations and seasons caused significant influences on the overall bacterial communities, which were mainly affected by temperature, sewage quality and bacterial survival preference, and 13 genera of sulfate-reducing bacteria (SRB), 2 genera of ammonia-oxidizing bacteria (AOB), 2 genera of nitrite-oxidizing bacteria (NOB), and 9 genera of water-related pathogenic bacteria (WPB) were detected in rural sewage collection systems. SRB, AOB, NOB, and WPB tended to inhabit in biofilms or deposits rather than in sewage. The total relative abundance of SRB in summer and autumn (∼2.19%) was higher than in winter and spring (∼0.41%), and the WPB distribution in different seasons showed significant distinction. Additionally, some of SRB, AOB, NOB, and WPB also showed significant differences in sewers and ditches. Overall, this study provided a deeper understanding of bacteria in rural sewage collection systems and could further provide the basic parameter for the operation and maintenance risk control. • Locations and seasons caused significant influences on bacterial communities. • SRB, AOB, NOB, and WPB tended to inhabit in biofilms or deposits. • Total abundance of SRB in summer and autumn was higher than in winter and spring. • Some of SRB, AOB, NOB, and WPB showed significant differences in sewers and ditches. [ABSTRACT FROM AUTHOR]

• SIF captures seasonal GPP dynamics better than EVI over the TP. • SIF shows strong response to interannual variability of snow cover. • SIF shows weak response to interannual variability of summer precipitation. Snow cover, which has been declining over recent decades because of rising temperatures, impacts alpine vegetation in various ways on the Tibetan Plateau (TP). However, it is still unclear how the alpine ecosystem responses to the rapid changes of snow cover on the TP. Here, we use the novel spaceborne measurements of solar-induced fluorescence (SIF) from the GOME-2 instrument, a direct proxy of photosynthetic activity, along with traditional vegetation indices (VIs) to study the responses of an alpine ecosystem to changes in snow cover over the TP. We find that seasonal dynamics of SIF are more consistent with alpine vegetation gross primary productivity (GPP) than those of enhanced vegetation index (EVI), suggesting the decoupling of photosynthesis and changes in greenness-based VIs. The snow cover explains most of the interannual variability of SIF, with secondary effects due to summer air temperature, while summer precipitation has little impact on alpine vegetation photosynthesis, indicating the critical role of snow cover in regulating alpine vegetation growth on the TP. This study suggests that the alpine vegetation photosynthesis on the TP is highly dependent on the snow cover at the start of the growing season and air temperature at the end of the growing season. Our results also demonstrate that the on-going satellite measurements of SIF shed new light on the understanding of future vegetation growth and vegetation–atmosphere interactions under a changing climate on the TP. [ABSTRACT FROM AUTHOR]

Perfluorooctanoic acid (PFOA) as nonbiodegradable organic pollutant, its presence and risks in wastewater treatment system has aroused wide concern. This study investigated the effect and underlying mechanism of PFOA on anaerobic digestion sludge (ADS) dewaterability. Long-term exposure experiments were set up to investigate the effect with various concentration of PFOA dosed. Experimental results suggested that the existence of high concentration PFOA (over 1000 μg/L) could deteriorate ADS dewaterability. The long-term exposure to 100,000 μg/L PFOA of ADS increased specific resistance filtration (SRF) by 81.57%. It was found that PFOA promoted the release of extracellular polymeric substances (EPS), which was strongly associated with sludge dewaterability. The fluorescence analysis revealed that the high PFOA concentration could significantly improve the percentage of protein-like substances and soluble microbial by-product-like content, and then further deteriorated the dewaterability. The FTIR results showed that long-term exposure of PFOA caused loose protein structure in sludge EPS, which led to loose sludge floc structure. The loose sludge floc structure aggravated the deterioration of sludge dewaterability. The solids-water distribution coefficient (K d) decreased with the increase of initial PFOA concentration. Moreover, PFOA significantly affected microbial community structure. Metabolic function prediction results showed significant decrease of fermentation function exposed to PFOA. This study revealed that the PFOA with high concentration could deteriorated sludge dewaterability, which should be highly concerned. [Display omitted] • The presence of PFOA can deteriorate anaerobic digested sludge dewaterability. • PFOA above 1000 μg/L promote the release of extracellular polymeric substances. • PFOA no less than 1000 μg/L led to loose sludge floc structure. • Percentage of solid phase PFOA decreased with the increase of initial PFOA dose. • PFOA significantly changed the microbe structures and functions. [ABSTRACT FROM AUTHOR]

Tibetan Plateau (TP) snow cover is featured by sub‐seasonal changes, affecting weather and climate in surrounding and downstream areas. Previous studies emphasize the effect of background atmospheric circulation on rapid changes of TP snow cover as a whole. However, spatial discrepant changes of snow cover over the TP with complex topography and uneven snowfall remain unaddressed. Our research indicates that snow cover fraction dominates the rapid changes of surface albedo across the TP, and snow depth also significantly influences surface albedo changes through modulating snow albedo in central and eastern TP with shallow snow. However, the excessive snow amount and empirical snow cover fraction schemes introduce spatially divergent biases of surface albedo changes in simulations. Our research highlights the instant response of TP surface albedo to both snow coverage and depth in snow season, and provides a promising perspective for improving TP snow and surface albedo simulations. Plain Language Summary: Tibetan Plateau (TP) snow cover is characterized not only by obvious seasonal changes, but also by rapid sub‐seasonal changes, which has a significant impact on the weather and climate of the downstream areas by affecting the surface albedo over the TP. Previous studies have generally concluded that the background atmospheric circulation dominates rapid changes of overall TP snow cover. However, rapid changes of snow cover exhibit spatial discrepancies over the TP with complex topography and uneven snowfall. Our study finds that snow coverage and depth both contribute to rapid changes of surface albedo and energy budget over the TP, which further lead to rapid changes of snow cover. However, current numerical models tend to overestimate the snow and fail to simulate spatial different changes of snow coverage and depth, leading to spatially divergent simulation biases in surface albedo, surface energy balance and local atmospheric circulation over the TP. Therefore, there is an urgent need to improve the snow parameterization in models to enhance the intra‐seasonal simulation of snow cover and surface albedo over the TP. Key Points: Observed surface albedo over the Tibetan Plateau (TP) has significant weekly scale fluctuations during winterSnow cover fraction and snow depth jointly dominate observed rapid changes of surface albedo over the TPExcessive snow amount and empirical snow cover fraction schemes lead to spatially divergent bias of surface albedo change [ABSTRACT FROM AUTHOR]

Essential proteins are important participants in various life activities and play a vital role in the survival and reproduction of living organisms. Identification of essential proteins from protein-protein interaction (PPI) networks has great significance to facilitate the study of human complex diseases, the design of drugs and the development of bioinformatics and computational science. Studies have shown that highly connected proteins in a PPI network tend to be essential. A series of computational methods have been proposed to identify essential proteins by analyzing topological structures of PPI networks. However, the high noise in the PPI data can degrade the accuracy of essential protein prediction. Moreover, proteins must be located in the appropriate subcellular localization to perform their functions, and only when the proteins are located in the same subcellular localization, it is possible that they can interact with each other. In this paper, we propose a new network-based essential protein discovery method based on sub-network partition and prioritization by integrating subcellular localization information, named SPP. The proposed method SPP was tested on two different yeast PPI networks obtained from DIP database and BioGRID database. The experimental results show that SPP can effectively reduce the effect of false positives in PPI networks and predict essential proteins more accurately compared with other existing computational methods DC, BC, CC, SC, EC, IC, NC. [ABSTRACT FROM AUTHOR]

Many applications of remote sensing only require the classification of a single land type. This is known as the one-class classification problem and it can be performed using either binary classifiers, by treating all other classes as the negative class, or one-class classifiers which only consider the class of interest. The key difference between these two approaches is in their training data and the amount of effort needed to produce it. Binary classifiers require an exhaustively labelled training data set while one-class classifiers are trained using samples of just the class of interest. Given ample and complete training data, binary classifiers generally outperform one-class classifiers. However, what is not clear is which approach is more accurate when given the same amount of labelled training data. That is, for a fixed labelling effort, is it better to use a binary or one-class classifier. This is the question we consider in this article. We compare several binary classifiers, including backpropagation neural networks, support vector machines, and maximum likelihood classifiers, with two one-class classifiers, one-class SVM, and presence and background learning (PBL), on the problem of one-class classification in high-resolution remote sensing imagery. We show that, given a fixed labelling budget, PBL consistently outperforms the other methods. This advantage stems from the fact that PBL is a positive-unlabelled method in which large amounts of readily available unlabelled data is incorporated into the training phase, allowing the classifier to model the negative class more effectively. [ABSTRACT FROM PUBLISHER]

Modeling the radiative transfer (RT) in heterogeneous forest scenes is important for understanding biophysical processes, as well as retrieving information from remotely sensed data. LiDAR (Light Detection and Ranging) is capable of providing highly detailed three-dimensional (3D) canopy structural information that can be used to parameterize RT models. In previous studies, point cloud data (such as terrestrial LiDAR data) are often voxelized with coarse resolutions, and the foliage voxels are often assumed to be turbid medium. In this study we propose a new voxel-based RT model, namely VBRT, that uses high resolution solid voxels to approximate 3D structure of forest more accurately than coarse resolution turbid medium voxels used in previous studies. Parallel computing techniques are used to speed up computation and the model can run on high performance computing (HPC) platforms. VBRT was tested in four virtual forest scenes, using the well-known physically based ray tracer (PBRT) as a benchmark. The Discrete Anisotropic Radiative Transfer (DART) model, which is based on turbid medium voxels, was also compared. Experimental results show that simulated digital imagery and bi-directional reflectance factor (BRF) by VBRT and PBRT are in good agreement, and the difference in simulation results can be reduced by using higher resolution voxels or larger number of samples per pixel. According to our test, parameterizing VBRT using high resolution terrestrial LiDAR data with 0.02 m voxels can produce more accurate results than DART with turbid medium voxels (0.1 m), although VBRT is more computation-intensive due to the use of higher resolution voxels. Our results indicate that VBRT has good potential in modeling radiation transfer in forests, as it is possible to parameterize the model using high density point cloud data such as terrestrial LiDAR data. [ABSTRACT FROM AUTHOR]

As structure-directing agents, the molecular structure of surfactants is critical for determining the properties of prepared mesoporous materials. Using dehydroabietic acid as a starting material, a series of rosin-based Gemini surfactants (abbreviated as R- n-R, n = 3, 6, 8 and 10, indicating the carbon atom number contained in the spacer) were synthesized and applied as templates in the preparation of ordered mesoporous silica. The structures and morphologies of the samples were characterized by X-ray diffraction, scanning electron microscope, transmission electron microscope and N adsorption-desorption. The R- n-R surfactants feature rigid tricyclic hydrophobic groups with large volumes, which are beneficial for the formation of a three-dimensional cubic phase. Furthermore, the spacer length was found to have a tremendous effect on the structure of the prepared mesoporous silica materials. The head group of R-3-R, which has a short spacer, is excessively charged, leading to silica nanoparticles with an irregular morphology and a rather low BET surface area. With longer spacer lengths, R-6-R, R-8-R and R-10-R are conducive to generating silica nanoparticles with a novel dumbbell-like morphology and with higher BET surface areas of 1171, 1096 and 1186 m g, respectively. The results demonstrate the particularities of the Gemini surfactant structure in the preparation of mesoporous silica nanoparticles with novel morphologies, and the details of the molecular interactions that occur in the condensation of silicate anions are also revealed. [ABSTRACT FROM AUTHOR]

While electric vehicle (EV) use has proliferated in developed countries, emerging nations have lagged behind because they lack the resources to establish effective EV charging networks. To address this issue, this paper has developed a framework through scenario analysis that aims to minimize the costs involved in establishing such networks and provide policy makers with insights on how to accomplish this. A given set of public institutions possessing EV fleets were first grouped into zones using clustering algorithms. Mathematical models were then developed to identify optimal EV charging station locations serving the EV fleets of these organizations, with an objective to minimize the total cost. Factors such as EV range anxiety and human walking distance were imbedded into the framework, which was examined using real world data from three major cities in Morocco: Rabat, Casablanca, and Fes. With the framework, policy makers can make better planning decisions on EV transitioning. [ABSTRACT FROM AUTHOR]

It has been well recognized that both the performance and operation stability of proton exchange membrane fuel cells (PEMFCs) are closely associated with water transport and accumulation behaviors in the membrane electrode assembly. Therefore, an optimal water management is highly desired. Conventional serpentine flow field (CSFF) can effectively facilitate water removal and prevent water flooding. However, CSFF would cause a high pressure drop from the inlet to outlet, thus resulting in large parasitic power loss. In this study, a novel three-dimensional flow field (WSFF), patterned with waved serpentine flow channels, is designed and analyzed by combing the simulating method with experimental method. A three-dimensional, multi-phase, steady, isothermal, laminar simulation model is firstly established based on FLUENT PEM fuel cell module, and this model reveals that WSFF is overall better than CSFF in promoting oxygen transport though the diffusion layer and removing liquid water accumulated in microstructure. Its periodic waved structure introduces cyclical variation of local flow direction, local flow velocity and local pressure, thus leading to enhanced forced-convection. The superior performance of WSFF has also been experimentally verified, proving that WSFF not only enables a lower pressure drop over the entire current density range, but also improves the cell performance in comparison to CSFF at high current density region. Specifically, there is a 17.8% increment in the peak power density due to the use of WSFF. [ABSTRACT FROM AUTHOR]

Accurate values of the nonlinear index of refraction n for the nonlinear optical crystals ZnGeP and AgGaS were measured using the Z-scan technique. The results were obtained using ~100-fs mid-infrared pulses from an OPA-DFG system driven by the 800-nm laser. The measured values of the AGS agree well with the theoretical values based on the two-band model for a direct band gap material. We confirmed the validity of the measured values for the indirect semiconductor ZGP by comparing the results with those obtained at ~1300 nm in a previous study. We have proved the broadening due to GVD is negligible in our experiments. We believe these nonlinear measurements of AGS and ZGP are meaningful for the analysis and design of optical systems in the mid-infrared region. [ABSTRACT FROM AUTHOR]

We numerically and experimentally investigate the astigmatism transfer phenomena in femtosecond optical parametric amplification (OPA). We model the OPA process based on the coupled second-order three-wave nonlinear propagation equations. The numerical and experimental results support that the input pump pulse astigmatism can be transferred into the idler pulse but not the signal pulse, and the idler pulse astigmatism originating from spatial walk-off is less than the idler pulse astigmatism received from the pump. Thus, we can provide a clear understanding of astigmatism transfer mechanisms in the OPA process, and make better use of broadband tunable OPA sources. [ABSTRACT FROM AUTHOR]

In this paper, the feedback signal of ultrasonic fatigue system was used to deduce the accumulated fatigue damage in situ using the ultrasonic nonlinearity parameter. It was observed that, compared with the decrease in resonant frequency, the ultrasonic nonlinearity parameter shows a greater sensitivity to fatigue damage evolution (i.e. crack initiation and propagation). Ultrasonic nonlinearity parameters obtained from tests conducted under various environmental humidity levels were monitored and analysed. Through changes in the ultrasonic nonlinearity parameter, it was concluded that both of the fatigue crack initiation life and crack propagation life were reduced by increasing the humidity levels. [ABSTRACT FROM AUTHOR]

Land surface processes play an important role in the East Asian Summer Monsoon (EASM) system. Parameterization schemes of land surface processes may cause uncertainties in regional climate model (RCM) studies for the EASM. In this paper, we investigate the sensitivity of a RCM to land surface parameterization (LSP) schemes for long-term simulation of the EASM. The Weather Research and Forecasting (WRF) Model coupled with four different LSP schemes (Noah-MP, CLM4, Pleim-Xiu and SSiB), hereafter referred to as Sim-Noah, Sim-CLM, Sim-PX and Sim-SSiB respectively, have been applied for 22-summer EASM simulations. The 22-summer averaged spatial distributions and strengths of downscaled large-scale circulation, 2-m temperature and precipitation are comprehensively compared with ERA-Interim reanalysis and dense station observations in China. Results show that the downscaling ability of RCM for the EASM is sensitive to LSP schemes. Furthermore, this study confirms that RCM does add more information to the EASM compared to reanalysis that imposes the lateral boundary conditions (LBC) because it provides 2-m temperature and precipitation that are with higher resolution and more realistic compared to LBC. For 2-m temperature and monsoon precipitation, Sim-PX and Sim-SSiB simulations are more consistent with observation than simulations of Sim-Noah and Sim-CLM. To further explore the physical and dynamic mechanisms behind the RCM sensitivity to LSP schemes, differences in the surface energy budget between simulations of Ens-Noah-CLM (ensemble mean averaging Sim-Noah and Sim-CLM) and Ens-PX-SSiB (ensemble mean averaging Sim-PX and Sim-SSiB) are investigated and their subsequent impacts on the atmospheric circulation are analyzed. It is found that the intensity of simulated sensible heat flux over Asian continent in Ens-Noah-CLM is stronger than that in Ens-PX-SSiB, which induces a higher tropospheric temperature in Ens-Noah-CLM than in Ens-PX-SSiB over land. The adaptive modulation of geopotential height gradients affects wind field (through geostrophic balance) simulation especially at lower levels, which subsequently affects the simulation of large-scale circulation, 2-m temperature and monsoon precipitation as well as RCM's downscaling ability. [ABSTRACT FROM AUTHOR]

Electromagnetic fields (EMFs) can improve pain, stiffness and physical function in osteoarthritis (OA) patients and have been proposed for the treatment of OA. However, the precise mechanisms involved in this process are still not fully understood. In the present study, we investigated the effects of exposure for different durations with 75 Hz, 2.3 mT sinusoidal EMFs (SEMFs) on the metabolism of lubricin of rat chondrocytes cultured in vitro. Our results showed that SEMFs exposure promoted lubricin synthesis in a time-dependent manner, and the expression of transforming growth factor (TGF)-β1 was also enhanced after SEMFs treatment. The up-regulation effect of the expression of lubricin under SEMF was partly reduced by SB431542, an inhibitor of TGF-RI kinase. The Smad pathway was also investigated in our study. Smad2 synthesis was higher in EMF-exposed condition than in controls, whereas no effects were observed on inhibitory Smads (Smad6 and Smad7) production. Altogether, these data suggest that SEMF exposure can promote lubricin synthesis of rat chondrocytes in a time-dependent manner and that the TGF-β/Smads signaling pathway plays a partial role. [ABSTRACT FROM PUBLISHER]

Imbalance in osteogenesis and adipogenesis of bone marrow stromal cells is a crucial pathological process of osteoporosis. P2×7-deficient mice were previously shown to exhibit an osteopenic phenotype and abnormal fat distribution, leading us to hypothesize that P2×7R activation was involved in the differentiation of BMSCs. Consequently, we investigated the effect of P2×7R activation on osteogenic and adipogenic differentiation of BMSCs in vitro, and established an ovariectomized (OVX) osteoporosis model to test P2×7R activation on adipocytes formation, trabecular and cortical bone parameters in vivo. Our results showed that activation of P2×7R by BzATP resulted in increase in the gene expression of osteoblastic markers, the activity of alkaline phosphatase and bone mineralization, and decrease in the gene expression of adipogenic markers and the number of adipocytes generated by BMSCs. MicroCT analysis showed that BzATP treatment ameliorated the micro-architecture of trabecular bones in OVX mice, while cortical bone parameters were unaffected. H&E staining analysis showed that was increase in the volume of trabecular bone and number of trabecular bone, and decrease in bone marrow adipocytes in BzATP-treated OVX mice compared with OVX mice. Also, activation of P2×7R transduced to ERK1/2 and JNK signaling pathways. This transduction was prevented by BBG, U0126, and SP600125. U0126 and SP600125 prevented BzATP-induced up-regulation of osteogenic-related genes expression and down-regulation of adipogenic-related genes expression. These data suggest that BzATP activates the differentiation of BMSCs into osteoblasts but not adipocytes by stimulating ERK1/2 and JNK signaling pathways in a P2×7R-dependent way. [ABSTRACT FROM AUTHOR]

Earth's surface warming by external forcing depends on location. Warming amplification, or greater surface warming than the global average, occurs in the Arctic and high-elevation regions, including the Tibetan Plateau (TP). We examined the major drivers of TP warming amplification in recent decades (1979–2020) and under future climate scenarios (2061–2100) by applying local energy budget diagnosis of multiple radiative kernels based on state-of-the-art reanalysis datasets and coupled model simulations. From 1979 to 2020, both the snow–albedo feedback and cloud–radiation feedback strongly affected the seasonality of TP warming (summer vs winter). Snow cover and albedo decreased significantly in winter but showed only small changes in summer. TP total and low-level cloud cover increased in summer, causing cooling, and decreased in winter, causing warming. During winter, TP warming amplification (1.84 from 1979 to 2020) is weaker than Arctic amplification (3.64) because the positive contribution of the surface albedo feedback to TP warming is not as strong as the dual warming effects of the lapse rate feedback and surface heat flux observed in the Arctic. Our attribution analyses based on the preindustrial control (piControl) and Historical simulations of phase 6 of the Coupled Model Intercomparison Project confirmed that TP warming is caused by external forcing. Because the external forcing associated with anthropogenic activity is increasing, TP warming will continue to the end of the twenty-first century. Under likely future warming scenarios, winter TP warming amplification is still less than in the Arctic due to the effects of the lapse rate feedback and surface heat flux. Significance Statement: Over the Tibetan Plateau, warming amplification, which refers to greater surface warming than the global average (∼75% more warming than the global average from 1979 to 2020), has resulted in melting permafrost, retreating glaciers, and decreasing biodiversity. This study quantified the relative effects of eight physical processes on the warming amplification over the Tibetan Plateau. In the boreal winter, the reduction in snow cover and albedo are the leading contributors (about 49%) to Tibetan Plateau warming, meaning that melting snow exposes darker ground that absorbs more sunlight than snow does. In a warmer future climate, continued melting snow cover is projected to further enhance Tibetan Plateau warming amplification. [ABSTRACT FROM AUTHOR]

In this paper, the feedback signal of ultrasonic fatigue system was used to in situ deduce the accumulated fatigue damage via ultrasonic nonlinearity parameter. It was observed that compared with the resonant frequency, the ultrasonic nonlinearity parameter shows a greater sensitivity to fatigue damage like crack initiation and crack propagation. Conventional fatigue testing was carried out and the variation of specimen rigidity and plastic strain of the material were obtained which correlated well with the ultrasonic nonlinearity parameter. Also, the ultrasonic fatigue crack initiation was verified by interrupted test. [ABSTRACT FROM AUTHOR]

The Tibetan Plateau (TP) summer monsoon (TPSM) is a unique monsoon system generated by the uplifted thermal forcing over the large-scale terrain. Considering both the dynamic and thermodynamic features of TPSM, we identified two distinct quasi-biweekly modes based on multivariate empirical orthogonal function analysis. The first mode shows a south–north-aligned pattern, related to interaction between the tropics and mid‐latitudes. In contrast, the second mode is generated by a southeastward‐propagating wave train crossing over Eurasia to form a west–east dipole distribution over the TP. The diagnostic results of a vorticity budget analysis and Rossby wave dynamics suggest that the first mode originates from the Mediterranean and propagates eastward along the westerly jet. As the upper-level vorticity anomaly approaches the northern TP, the vorticity advection induced by zonal background winds shows a leading phase to the southern sector of the TP, inducing southward movement. Once the southward-moving upper‐level vorticity arrives over the Indian peninsula, it is coupled with tropical convection disturbances in the low level, whereupon they together propagate northwestward. The wave train associated with the second mode originates from the North Atlantic. Its southeastward propagation is also related to the advection of vorticity perturbations caused by background westerly mean flows. Before reaching the western TP, the vorticity anomalies of the wave train are well-organized and quasi‐barotropic in structure. The blocking effect of the TP topography seems to disturb the wave structure. The movements of lower‐level vorticity and diabatic heating slow down and form a baroclinic structure over the TP. [ABSTRACT FROM AUTHOR]

This research study investigates the fatigue properties of resistance spot welds (RSWs) made from selective laser‐melted (SLMed) maraging steel (MS1) and compares them with dual‐phase (DP) steel RSWs. The findings reveal that MS1 spot welds exhibit superior fatigue properties compared with DP steel RSWs, regardless of the printing orientation of the MS1 substrate. Furthermore, fatigue fracture occurs at the MS1 substrate, with a transition of fracture location observed from MS1 to itself and MS1‐to‐DP600 dissimilar welds. The results of structural stress analysis indicate that the weld nugget diameter is not the only factor affecting the fatigue life. The study also highlights the importance of considering materials inhomogeneity and fracture modes in fatigue life assessment. Based on the findings, the study recommends the development of a new fatigue life prediction curve for spot welds of additive manufacturing (AM) materials. Such a curve would be beneficial in promoting the further application of AM technology for functional parts of design verification vehicles (DCV) and production cars. Overall, the research contributes to the understanding of the fatigue properties of RSWs made from SLMed MS1 and DP steel, which has implications for the design and manufacturing of parts in the automotive industry. Highlights: SLMed MS1 RSWs showed superior fatigue properties compared with DP600‐DP600 spot welds.Softening occurred at weld nugget for MS1‐MS1 RSWs while at HAZ of MS1 for MS1‐DP600 RSWs.Fatigue fracture occurred in MS1 steel for MS1‐DP600 RSWs due to the defects in MS1 sheets.The lower constant m for MS1 than that of other steels explained different fatigue life. [ABSTRACT FROM AUTHOR]

Solid-state lithium batteries (SSLBs) are promising energy storage devices in the future due to their high theoretical energy density and enhanced safety. However, the practical energy density of SSLBs is severely constrained by the limited mass loading of cathode materials, which is related to sluggish charge transfer inside the thick cathodes. In this work, the solid-state batteries with high-mass-loading cathodes are realized by introduction of three-dimensional (3D) electronic-conductivity current collectors and in situ solidification of polymer electrolytes. The porous electronic current collectors of 3D carbon felts accommodate the flowing cathode slurry with considerably increased loading of cathode materials. Subsequently, the in situ solidified polymer electrolytes ensure conformal ionic conducting channels inside the cathodes, along with the formation of intimate and flexible contacts at cathode/electrolyte interfaces. In this way, the solid-state LiFePO4/garnet/Li batteries with cathode loading of 6.2 mg cm−2 show an initial discharge capacity of 159.4 mAh g−1 and a capacity retention of 92.1% after 100 cycles at 30 °C and 0.1 C. Furthermore, the cathode mass loading as high as 27.8 mg cm−2 is achieved with a corresponding areal capacity of approximately 4.2 mAh cm−2. This work proposes a promising unique cathode architecture for solid-state lithium batteries with high mass loading of the cathode. [ABSTRACT FROM AUTHOR]

Salmonella enteritidis (S. enteritidis) outbreaks continue to occur, and have increased public awareness of this pathogen. Nicking endonuclease Nb.BbvC I is widely used for the detection of biomolecules and displays activity for specific double-stranded DNA (dsDNA). In this study, we developed a biosensor to detect S. enteritidis based on fluorescence resonance energy transfer (FRET) using nicking enzyme and carbon nanoparticles (CNPs). Because of the quenching effect of black hole quencher 1 (BHQ 1), the CNPs do not fluoresce in the reaction system. When the target bacteria are added, the nicking enzyme recognizes and cleaves the dsDNA fabricated by the interaction between probe and target. As a result, the CNPs dissociate from BHQ 1and emit strong fluorescence. Using the nicking enzyme, the fluorescence signals of the biosensor are greatly amplified. The biosensor exhibited a linear relationship with the concentration of S. enteritidis ranging from 102 to 3×103 CFU/mL in water and from 1.5×102 to 3×103 CFU/mL in milk. The present results indicate that our FRET-based detection system can be widely employed for the effective detection of pathogens. [ABSTRACT FROM AUTHOR]

It is very common that only presence data are available in ecological niche modeling. However, most existing methods for evaluating the accuracy of presence-absence (binary) predictions of species require presence-absence data. The aim of this study is to present a new method for accuracy assessment that does not rely on absence data. Two new statistics Fpb and Fcpb were derived based on presence-background data. With generated six virtual species, we used DOMAIN, generalized linear modeling (GLM), and maximum entropy (MAXENT) to produce different species presence-absence predictions. To investigate the effectiveness of the new statistics in accuracy assessment, we used Fpb, Fcpb, the traditional F-measure ( F), kappa coefficient, true skill statistic (TSS), area under the receiver operating characteristic curve (AUC), and the contrast validation index (CVI) to evaluate the accuracy of predictions, and the behaviors of these accuracy measures were compared. The effectiveness of Fpb for threshold selection and estimation of species prevalence was also investigated. Experimental results show that Fcpb is an estimate of F. The Pearson's correlation coefficient (COR) between Fcpb and F is 0.9882, with a root-mean-square error (RMSE) of 0.0171. In general, Fpb, Fcpb, F, kappa coefficient, TSS, and CVI can sort models by the accuracy of binary prediction, but AUC is not appropriate to evaluate the accuracy of binary prediction. For DOMAIN, GLM, and MAXENT, finding the threshold by maximizing Fpb and by maximizing F result in similar accuracies. In addition, the estimation of species prevalence based on binary output with maximizing Fpb as the thresholding method is significantly more accurate than simply averaging the original continuous output. The best estimate of prevalence is provided by the binary output of MAXENT, with an RMSE of 0.0116. Finally, we conclude that the new method is promising in accuracy assessment, threshold selection, and estimation of species prevalence, all of which are important but challenging problems with presence-only data. Because it does not require absence data, the new method will have important applications in ecological niche modeling. [ABSTRACT FROM AUTHOR]