Solar cell defect detection is crucial for quality inspection in photovoltaic power generation modules.In the production process,defect samples occur infrequently and exhibit random shapes and sizes,which makes it cha...Solar cell defect detection is crucial for quality inspection in photovoltaic power generation modules.In the production process,defect samples occur infrequently and exhibit random shapes and sizes,which makes it challenging to collect defective samples.Additionally,the complex surface background of polysilicon cell wafers complicates the accurate identification and localization of defective regions.This paper proposes a novel Lightweight Multiscale Feature Fusion network(LMFF)to address these challenges.The network comprises a feature extraction network,a multi-scale feature fusion module(MFF),and a segmentation network.Specifically,a feature extraction network is proposed to obtain multi-scale feature outputs,and a multi-scale feature fusion module(MFF)is used to fuse multi-scale feature information effectively.In order to capture finer-grained multi-scale information from the fusion features,we propose a multi-scale attention module(MSA)in the segmentation network to enhance the network’s ability for small target detection.Moreover,depthwise separable convolutions are introduced to construct depthwise separable residual blocks(DSR)to reduce the model’s parameter number.Finally,to validate the proposed method’s defect segmentation and localization performance,we constructed three solar cell defect detection datasets:SolarCells,SolarCells-S,and PVEL-S.SolarCells and SolarCells-S are monocrystalline silicon datasets,and PVEL-S is a polycrystalline silicon dataset.Experimental results show that the IOU of our method on these three datasets can reach 68.5%,51.0%,and 92.7%,respectively,and the F1-Score can reach 81.3%,67.5%,and 96.2%,respectively,which surpasses other commonly usedmethods and verifies the effectiveness of our LMFF network.展开更多
Mg alloys have the defects of low stiffness,low strength,and high coefficient of thermal expansion(CTE).The composites strategy and its architecture design are effective approaches to improve the comprehensive perform...Mg alloys have the defects of low stiffness,low strength,and high coefficient of thermal expansion(CTE).The composites strategy and its architecture design are effective approaches to improve the comprehensive performance of materials,but the processing difficulty,especially in ceramics forming,limits the control and innovation of material architecture.Here,combined with 3D printing and squeeze infiltration technology,two precisely controllable architectures of AZ91/Al_(2)O_(3)interpenetrating phase composites(IPC)with ceramic scaffold were prepared.The interface,properties and impact of different architecture on IPC performance were studied by experiments and finite element simulation.The metallurgical bonding of the interface was realized with the formation of MgAl_(2)O_(4)reaction layer.The IPC with 1 mm circular hole scaffold(1C-IPC)exhibited significantly improved elastic modulus of 164 GPa,high compressive strength of 680 MPa,and good CTE of 12.91×10^(-6)K^(−1),which were 3.64 times,1.98 times and 55%of the Mg matrix,respectively.Their elastic modulus,compressive strength,and CTE were superior to the vast majority of Mg alloys and Mg based composites.The reinforcement and matrix were bicontinuous and interpenetrating each other,which played a critical role in ensuring the potent strengthening effect of the Al_(2)O_(3)reinforcement by efficient load transfer.Under the same volume fraction of reinforcements,compared to IPC with 1 mm hexagonal hole scaffold(1H-IPC),the elastic modulus and compressive strength of 1C-IPC increased by 15%and 28%,respectively,which was due to the reduced stress concentration and more uniform stress distribution of 1C-IPC.It shows great potential of architecture design in improving the performance of composites.This study provides architectural design strategy and feasible preparation method for the development of high performance materials.展开更多
A novel three-dimensional (3D) layered MoS2@graphene functionalized with nitrogen-doped graphene quantum dots (MoS2@N-GQDs-GR) composites as an enhanced electrochemical hydrogen evolution catalyst. The few layered MoS...A novel three-dimensional (3D) layered MoS2@graphene functionalized with nitrogen-doped graphene quantum dots (MoS2@N-GQDs-GR) composites as an enhanced electrochemical hydrogen evolution catalyst. The few layered MoS2 nanoflowers supported on N-GQDs-GR surface were elaborately fabricated by one-pot hydrothermal method, which MoS2 and N-GQDs-GR exist in a bonding manner of Mo-N. In addition, due to the layered MoS2 sheet edge exposes more hydrogen evolution active sites and N-GQDs-GR have high conductivity, the composites exhibit prominent electrocatalytic activity with a low overpotential 99 mV, a small Tafel slope 49.3 mV/dec. Therefore, that the current work will develop HER catalysts may replace Pt.展开更多
Background The skeletal muscle of pigs is vulnerable to oxidative damage,resulting in growth retardation.Selenoproteins are important components of antioxidant systems for animals,which are generally regulated by diet...Background The skeletal muscle of pigs is vulnerable to oxidative damage,resulting in growth retardation.Selenoproteins are important components of antioxidant systems for animals,which are generally regulated by dietary selenium(Se)level.Here,we developed the dietary oxidative stress(DOS)-inducing pig model to investigate the protective effects of selenoproteins on DOS-induced skeletal muscle growth retardation.Results Dietary oxidative stress caused porcine skeletal muscle oxidative damage and growth retardation,which is accompanied by mitochondrial dysfunction,endoplasmic reticulum(ER)stress,and protein and lipid metabolism disorders.Supplementation with Se(0.3,0.6 or 0.9 mg Se/kg)in form of hydroxy selenomethionine(OH-SeMet)linearly increased muscular Se deposition and exhibited protective effects via regulating the expression of selenotranscriptome and key selenoproteins,which was mainly reflected in lower ROS levels and higher antioxidant capacity in skeletal muscle,and the mitigation of mitochondrial dysfunction and ER stress.What’s more,selenoproteins inhibited DOS induced protein and lipid degradation and improved protein and lipid biosynthesis via regulating AKT/mTOR/S6K1 and AMPK/SREBP-1 signalling pathways in skeletal muscle.However,several parameters such as the activity of GSH-Px and T-SOD,the protein abundance of JNK2,CLPP,SELENOS and SELENOF did not show dose-dependent changes.Notably,several key selenoproteins such as MSRB1,SELENOW,SELENOM,SELENON and SELENOS play the unique roles during this protection.Conclusions Increased expression of selenoproteins by dietary OH-SeMet could synergistically alleviate mitochondrial dysfunction and ER stress,recover protein and lipid biosynthesis,thus alleviate skeletal muscle growth retardation.Our study provides preventive measure for OS-dependent skeletal muscle retardation in livestock husbandry.展开更多
This study was designed to investigate the effect of 002C-3, a derivative of magnolol, on transient cerebral middle occlusion （tMCAO） in a mice model and to identify the underlying mechanisms. 002C-3 （100 and 150 p...This study was designed to investigate the effect of 002C-3, a derivative of magnolol, on transient cerebral middle occlusion （tMCAO） in a mice model and to identify the underlying mechanisms. 002C-3 （100 and 150 pg/kg, i.v. after ending occlusion） significantly reduced neurological deficit scores, infarct volumes, and brain water contents after 1.5 h MCAO and 24 h reperfusion. 002C-3 （75 150μg/kg） decreased the exudation of Evans blue from brain capillaries. 002C-3 （100 μg/kg） significantly inhibited the activity of MMP-9 and MMP-2 in the injured hemisphere. 002C-3 decreased the expression of autophagy-associated proteins, Beclin-1 and LC3B-Ⅱ, and increased the level of p62 in injured hemisphere. 002C-3 （100 pg/kg） significantly increased the expression of p-CaMKIV and p-HDAC4 in injured hemisphere. In conclusion, 002C-3 shows a neuroprotective effect on tMCAO injury in mice, and its mechanisms may be associated with alleviation of blood-brain barrier damage caused by the activation of MMPs, inhibition of autophagy, and stimulation of calcium signals related to cell survival. These findings suggest that 002C-3 is a neuroprotective agent that acts on multiple pathways.展开更多
OBJECTIVE： This study investigated how polypeptide 2B1 is involved in regulating and governing dampness in rat models with dampness pattern defined in terms of Traditional Chinese Medicine. METHODS： We randomly divi...OBJECTIVE： This study investigated how polypeptide 2B1 is involved in regulating and governing dampness in rat models with dampness pattern defined in terms of Traditional Chinese Medicine. METHODS： We randomly divided 48 SPF 10-week-old male Sprague-Dawley （SD） rats into a normal group, normal ＋ Aristolochic acid I （AA-I） for 5 min group, normal ＋ AA-I for 60 min group, dampness pattern group （DS-Group）, dampness pattern ＋ AA-I for 5 rain tern ＋ AA-I for 60 min group, and dampness pat- group. Groups were then treated accordingly. We took out the lung, stom- ach, liver, spleen, kidney, large intestine, and small intestine tissues to detect gene and protein expres- sion of organic anion transporter polypeptide 2B1 （OATP2B1）. RESULTS= Gene expression of OATP2B1 in spleen, kidney, and small intestine of rats with dampness pattern was lower than that in normal rats （P〈0.05）. The gene expressions of OATP2B1 in liver, stomach, large intestine, and small intestine were lower than that in control rats at different time points after being stimulated by AA-I （P〈0.05）. CONCLUSION There is coordination among multiple viscera in handling the condition of dampness, and the mechanism underlying the action may rely on regulating the expression of OATP2B1.展开更多
A cold-model vertical multi-tube circulating fluidized bed evaporator was designed and built to conduct a visualization study on the pressure drop of a liquid–solid two-phase flow and the corresponding particle distr...A cold-model vertical multi-tube circulating fluidized bed evaporator was designed and built to conduct a visualization study on the pressure drop of a liquid–solid two-phase flow and the corresponding particle distribution.Water and polyformaldehyde particle(POM)were used as the liquid and solid phases,respectively.The effects of operating parameters such as the amount of added particles,circulating flow rate,and particle size were systematically investigated.The results showed that the addition of the particles increased the pressure drop in the vertical tube bundle.The maximum pressure drop ratios were 18.65%,21.15%,18.00%,and 21.15%within the experimental range of the amount of added particles for POM1,POM2,POM3,and POM4,respectively.The pressure drop ratio basically decreased with the increase in the circulating flow rate but fluctuated with the increase in the amount of added particles and particle size.The difference in pressure drop ratio decreased with the increase in the circulating flow rate.As the amount of added particles increased,the difference in pressure drop ratio fluctuated at low circulating flow rate but basically decreased at high circulating flow rate.The pressure drop in the vertical tube bundle accounted for about 70%of the overall pressure drop in the up-flow heating chamber and was the main component of the overall pressure within the experimental range.Three-dimensional phase diagrams were established to display the variation ranges of the pressure drop and pressure drop ratio in the vertical tube bundle corresponding to the operating parameters.The research results can provide some reference for the application of the fluidized bed heat transfer technology in the industry.展开更多
Background:Chronic heat stress(CHS)disrupts hepatic metabolic homeostasis and jeopardizes product quality of pigs.Selenium(Se)may regulate the metabolic state through affect selenoprotein.Thus,we investigate the prote...Background:Chronic heat stress(CHS)disrupts hepatic metabolic homeostasis and jeopardizes product quality of pigs.Selenium(Se)may regulate the metabolic state through affect selenoprotein.Thus,we investigate the protective effect of dietary hydroxy-4-methylselenobutanoic acid(HMSeBA)on CHS induced hepatic metabolic disorder in growing pigs,and the corresponding response of selenoprotein.Methods:Forty crossbreed growing pigs were randomly assigned to five groups:control group raised in the thermoneutral environment(22±2℃)with basal diet;four CHS groups raised in hyperthermal condition(33±2℃)with basal diet and supplied with 0.0,0.2,0.4,and 0.6 mg Se/kg HMSeBA,respectively.The trial lasted 28 d.The serum biochemical,hepatic metabolism related enzyme,protein and gene expression and 25 selenoproteins in liver tissue were determined by real-time PCR,ELISA and western blot.Results:CHS significantly increased the rectal temperature,respiration rate,serum aspartate aminotransferase(AST)and low-density lipoprotein cholesterol(LDL-C)of pigs,up-regulated hepatic heat shock protein 70(HSP70)and induced lower liver weight,glycogen content,hepatic glucokinase and glutathione peroxidase(GSH-Px).The CHSinduced liver metabolic disorder was associated with the aberrant expression of 6 metabolism-related gene and 11 selenoprotein encoding genes,and decreased the protein abundance of GCK,GPX4 and SELENOS.HMSeBA improved anti-oxidative capacity of liver.0.4 or 0.6 mg Se/kg HMSeBA supplementation recovered the liver weight,glycogen content and rescue of mRNA abundance of genes related to metabolism and protein levels of GCK.HMSeBA supplementation changed expressions of 15 selenoprotein encoding genes,and enhanced protein expression of GPX1,GPX4 and SELENOS in the liver affected by CHS.CHS alone showed no impact while HMSeBA supplementation increased protein levels of p-AMPKαin the liver.Conclusions:In summary,HMSeBA supplementation beyond nutrient requirement mitigates CHS-induced hepatic metabolic disorder,recovered the liver glycogen content and the processes that are associated with the activation of AMPK signal and regulation of selenoproteins in the liver of growing pigs.展开更多
COVID-19 has become a global public health crisis since its outbreak in China in December 2019.Currently there are few clinically effective drugs to combat SARS-CoV-2 infection.The main protein(M^(pro)),papain-like pr...COVID-19 has become a global public health crisis since its outbreak in China in December 2019.Currently there are few clinically effective drugs to combat SARS-CoV-2 infection.The main protein(M^(pro)),papain-like protease(PL^(pro))and RNA-dependent RNA polymerase(RdRp)of SARS-CoV-2 are involved in the viral replication,and might be prospective targets for anti-coronavirus drug development.Here,we investigated the antiviral activity of oridonin,a natural small-molecule compound,against SARS-CoV-2 infection in vitro.The time-of-addition analysis showed that oridonin efficiently inhibited SARS-CoV-2 infection by interfering with the genome replication at the post-entry stage.Mechanistically,the inhibition of viral replication by oridonin depends on the oxidation activity ofα,β-unsaturated carbonyl.Further experiments showed that oridonin not only effectively inhibited SARS-CoV-2 Mpro activity,but also had some inhibitory effects on PLpro-mediated deubiquitinating and viral polymerase-catalyzed RNA elongation activities at high concentrations.In particular,oridonin could inhibit the bat SARS-like CoV and the newly emerged SARS-CoV-2 omicron variants(BA.1 and BA.2),which highlights its potential as a pan-coronavirus antiviral agent.Overall,our data provide strong evidence that oridonin is an efficient antiviral agent against SARS-CoV-2 infection.展开更多
Unsupervised methods based on density representation have shown their abilities in anomaly detection,but detection performance still needs to be improved.Specifically,approaches using normalizing flows can accurately ...Unsupervised methods based on density representation have shown their abilities in anomaly detection,but detection performance still needs to be improved.Specifically,approaches using normalizing flows can accurately evaluate sample distributions,mapping normal features to the normal distribution and anomalous features outside it.Consequently,this paper proposes a Normalizing Flow-based Bidirectional Mapping Residual Network(NF-BMR).It utilizes pre-trained Convolutional Neural Networks(CNN)and normalizing flows to construct discriminative source and target domain feature spaces.Additionally,to better learn feature information in both domain spaces,we propose the Bidirectional Mapping Residual Network(BMR),which maps sample features to these two spaces for anomaly detection.The two detection spaces effectively complement each other’s deficiencies and provide a comprehensive feature evaluation from two perspectives,which leads to the improvement of detection performance.Comparative experimental results on the MVTec AD and DAGM datasets against the Bidirectional Pre-trained Feature Mapping Network(B-PFM)and other state-of-the-art methods demonstrate that the proposed approach achieves superior performance.On the MVTec AD dataset,NF-BMR achieves an average AUROC of 98.7%for all 15 categories.Especially,it achieves 100%optimal detection performance in five categories.On the DAGM dataset,the average AUROC across ten categories is 98.7%,which is very close to supervised methods.展开更多
Background At presenti heat stress(HS)has become a key factor that impairs broiler breeding industry,which causes growth restriction and poor meat quality of broilers.S elenium(Se)is an excellent antioxidant and plays...Background At presenti heat stress(HS)has become a key factor that impairs broiler breeding industry,which causes growth restriction and poor meat quality of broilers.S elenium(Se)is an excellent antioxidant and plays a unique role in meat quality improvement.Recent years,nano-selenium(NanoSe)has received tremendous attention in livestock production,due to its characteristic and good antibacterial performance in vitro.Here,we developed the heat stressed-broiler model to investigate the protective effects of NanoSe on growth performance and meat quality of broilers and compare whether there are differences with that of other Se sources(Sodium selenite,SS;Selenoyeast,SeY;Selenomethioninec SeMet).Results HS jeopardized the growth performance and caused poor meat quality of breast muscle in broilers,which were accompanied by lowered antioxidant capacity,increased glycolysis,increased anaerobic metabolism of pyruvate,mitochondrial stress and abnormal mitochondrial tricarboxylic acid(TCA)cycle.All Se sources supplementation exhibited protective effects,which increased the Se concentration and promoted the expression of selenoproteins,improved the mitochondrial homeostasis and the antioxidant capacity,and promoted the TCA cycle and the aerobic metabolism of pyruvate,thus improved the breast muscle meat quality of broilers exposed to HS.However,unlike the other three Se sources,the protective effect of NanoSe on meat quality of heat stressed-broilers was not ideal,which exhibited limited impact on the pH value,drip loss and cooking loss of the breast muscle.Compared with the other Se sources,broilers received NanoSe showed the lowest levels of slow MyHC,the highest levels of fast MyHC and glycogen,the highest mRNA levels of glycolysis-related genes(PFKM and PKM),the highest protein expression of H5P60 and CLPP,and the lowest enzyme activities of GSH-Px,citroyl synthetase(CS)and isocitrate dehydrogenase(ICD)in breast muscle.Consistent with the SS,the Se deposition in breast muscle of broilers received NanoSe was lower than that of broilers received SeY or SeMet.Besides,the regulatory effciency of NanoSe on the expression of key selenoproteins(such as SELENOS)in breast muscle of heat stressed-broilers was also worse than that of other Se Sources.Conclusion Through comparing the meat quality,Se deposition,muscle fiber type conversion,glycolysis,mitochondrial homeostasis,and hond rial TCA cycle-related indicators of breast muscle in heat stressed broilers,we found that the protective effects of organic Se(SeY and SeMet)are better than that of inorganic Se(SS)and NanoSe.As a new Se source,though Nanose showed some protective effect on breast muscle meat quality of heat stressed broilers,the protective effect of NanoSe is not ideal,compared with other Se sources.展开更多
Recent research shows that China is experiencing significant greening,with afforestation initiatives being the main cause.Quantitative calculation of vegetation change influencing factors and evaluation of the contrib...Recent research shows that China is experiencing significant greening,with afforestation initiatives being the main cause.Quantitative calculation of vegetation change influencing factors and evaluation of the contribution of afforestation to vegetation greening in China are critical to coping with climate change and improving the implementation and efficacy of forestry projects.We investigated the temporal and spatial dynamics of the Normalized Difference Vegetation Index(NDVI)from 1982 to 2020,and quantified the contribution of afforestation initiatives,a typical human activity,to the dynamic changes of vegetation.The results showed that NDVI in China has primarily increased in the last 39 years.57%of the pixels increased,27%were stable and unchanged,and 16%decreased.Climate change was responsible for 72.34%of vegetation restoration,while human activities were responsible for 27.36%of vegetation restoration,according to residual analysis.In the future,only 14%of the regions showed continuous growth of the NDVI,while the remaining regions showed obvious antipersistence(59%will go from increasing to decreasing,and 22%will go from decreasing to increasing).The contribution of climate factors to vegetation change will decrease in the future,and human activities will become more complex.Except for Huaihe River and Taihu Lake(SPHRTL),other forestry projects showed an increasing trend of NDVI after the implementation of ecological engineering.However,due to differences in climate conditions and ecological engineering implementation,there are differences in the benefits of forestry projects.Some forestry project areas still have obvious vegetation degradation,and appropriate forestry management is necessary.This work provides a quantitative analysis of vegetation change and its driving factors in China,which will help to cope with future climate change and provide a reference for the implementation and management of ecological projects.展开更多
Objective: To explore the significance of dual-energy CT non-linear fusion technique in improving the quality of CTA image of renal cancer. Methods: The CTA images of 100 patients who had been confirmed by pathology a...Objective: To explore the significance of dual-energy CT non-linear fusion technique in improving the quality of CTA image of renal cancer. Methods: The CTA images of 100 patients who had been confirmed by pathology as renal cancer were collected and were randomly divided into experimental group and control group with 50 cases respectively. The two groups of patients were treated with iodine concentration of 300 mg/ml and 350 mg/ml non-ionic contrast agent, with a dosage of 1.5 ml/kg and an injection rate of 4 ml/s. The contrast agent intelligently tracking method was adopted bolus. The control group used the conventional CTA scanning, with a reference tube voltage/tube current of 100 kv/ref150 mas. The experimental group adopted the double energy scanning, with ball tube A and ball tube B. The reference tube voltage/tube current was 100 kv/ref250 mas and sn150 kv/ref125 mas respectively. The images of the experimental group were non-linear fused to obtain the Mono+ 55 kev single-energy images. The CT value, SNR contrast ratio of the abdominal aorta, renal artery and tumor tissue of the experimental group images and the 100 KV images and the Mono+ 55 kev images of the control group were compared. The objective evaluation and subjective evaluation of the image quality of the three groups of images was performed. Results: The results showed that the 100 kV images of the experimental group were statistically different from those of the control group (P05) in CT value, SNR and CNR (P 0.05). And there was no statistically significant difference between the non-linear fusion single-energy Mono+ 55 kev images and the control group images in CT value, SNR and CNR (P > 0.05). The subjective evaluation of image quality showed that there was no significant difference between Mono+ 55 kev images and control group images, and the quality of Mono+ 55 kev images was higher than that of experimental group 100 kV images. Conclusion: The dual-energy CT non-linear fusion technique can improve the quality of CTA image in patients with renal cancer, and it is possible to obtain high quality CTA images with low iodine concentration contrast agent.展开更多
It is generally believed that a major cause of motor dysfunction is the impairment in neural network that controls movement. But little is known about the underlying mechanisms of the impairment in cortical control or...It is generally believed that a major cause of motor dysfunction is the impairment in neural network that controls movement. But little is known about the underlying mechanisms of the impairment in cortical control or in the neural connections between cortex and muscle that lead to the loss of motor ability. So understanding the functional connection between motor cortex and effector muscle is of utmost importance. Previous study mostly relied on cross-correlation, coherence functions or model based approaches such as Granger causality or dynamic causal modeling. In this work the information transfer index (ITI) was introduced to describe the information flows between motor cortex and muscle. Based on the information entropy the ITI can detect both linear and nonlinear interaction between two signals and thus represent a very comprehensive way to define the causality strength. The applicability of ITI is investigated based on simulations and electroencephalogram (EEG), surface electromyography (sEMG) recordings in a simple motor task.展开更多
Spinal muscular atrophy （SMA） is an autosomal recessive neuromuscular disorder characterized by degeneration and loss of anterior horn cells in the spinal cord and brain stem nuclei, leading to progressive limb and ...Spinal muscular atrophy （SMA） is an autosomal recessive neuromuscular disorder characterized by degeneration and loss of anterior horn cells in the spinal cord and brain stem nuclei, leading to progressive limb and trunk paralysis and muscular atrophy. Depending on the age of onset and maximum muscular function achieved, SMA is recognized as SMA1, SMA2, SMA3 or SMA4, and most patients have a deletion or truncation of the survival motor neuron 1 （SMN1） gene. In this report, we present a patient with a mild SMA phenotype, SMA3, and define his genetic abnormality. Tetra-primer amplification refractory mutation system PCR combined with restriction fragment length polymorphism analysis and array comparative genomic hybridization were used to determine the genetic variations in this patient. A 500 kb deletion in chromosome 5q13.2, including homozygous deletion of neuronal apoptosis inhibitory protein, and heterozygous deletion of occludin and B-double prime 1 was identified. This SMA region deletion did not involve SMN, indicating that SMN was likely to function normally. The phenotype was dependent of the large deletion and neuronal apoptosis inhibitory protein, occludin and B-double prime 1 may be candidate genes for SMA3.展开更多
基金supported in part by the National Natural Science Foundation of China under Grants 62463002,62062021 and 62473033in part by the Guiyang Scientific Plan Project[2023]48–11,in part by QKHZYD[2023]010 Guizhou Province Science and Technology Innovation Base Construction Project“Key Laboratory Construction of Intelligent Mountain Agricultural Equipment”.
文摘Solar cell defect detection is crucial for quality inspection in photovoltaic power generation modules.In the production process,defect samples occur infrequently and exhibit random shapes and sizes,which makes it challenging to collect defective samples.Additionally,the complex surface background of polysilicon cell wafers complicates the accurate identification and localization of defective regions.This paper proposes a novel Lightweight Multiscale Feature Fusion network(LMFF)to address these challenges.The network comprises a feature extraction network,a multi-scale feature fusion module(MFF),and a segmentation network.Specifically,a feature extraction network is proposed to obtain multi-scale feature outputs,and a multi-scale feature fusion module(MFF)is used to fuse multi-scale feature information effectively.In order to capture finer-grained multi-scale information from the fusion features,we propose a multi-scale attention module(MSA)in the segmentation network to enhance the network’s ability for small target detection.Moreover,depthwise separable convolutions are introduced to construct depthwise separable residual blocks(DSR)to reduce the model’s parameter number.Finally,to validate the proposed method’s defect segmentation and localization performance,we constructed three solar cell defect detection datasets:SolarCells,SolarCells-S,and PVEL-S.SolarCells and SolarCells-S are monocrystalline silicon datasets,and PVEL-S is a polycrystalline silicon dataset.Experimental results show that the IOU of our method on these three datasets can reach 68.5%,51.0%,and 92.7%,respectively,and the F1-Score can reach 81.3%,67.5%,and 96.2%,respectively,which surpasses other commonly usedmethods and verifies the effectiveness of our LMFF network.
基金supported by the National Key Research and Development Program of China(No.2022YFB3708400)the National Natural Science Foundation of China(No.52305158)+1 种基金the Young Elite Scientists Sponsorship Program by CAST(No.2022QNRC001)the Science Innovation Foundation of Shanghai Academy of Spaceflight Technology(No.USCAST2021-18).
文摘Mg alloys have the defects of low stiffness,low strength,and high coefficient of thermal expansion(CTE).The composites strategy and its architecture design are effective approaches to improve the comprehensive performance of materials,but the processing difficulty,especially in ceramics forming,limits the control and innovation of material architecture.Here,combined with 3D printing and squeeze infiltration technology,two precisely controllable architectures of AZ91/Al_(2)O_(3)interpenetrating phase composites(IPC)with ceramic scaffold were prepared.The interface,properties and impact of different architecture on IPC performance were studied by experiments and finite element simulation.The metallurgical bonding of the interface was realized with the formation of MgAl_(2)O_(4)reaction layer.The IPC with 1 mm circular hole scaffold(1C-IPC)exhibited significantly improved elastic modulus of 164 GPa,high compressive strength of 680 MPa,and good CTE of 12.91×10^(-6)K^(−1),which were 3.64 times,1.98 times and 55%of the Mg matrix,respectively.Their elastic modulus,compressive strength,and CTE were superior to the vast majority of Mg alloys and Mg based composites.The reinforcement and matrix were bicontinuous and interpenetrating each other,which played a critical role in ensuring the potent strengthening effect of the Al_(2)O_(3)reinforcement by efficient load transfer.Under the same volume fraction of reinforcements,compared to IPC with 1 mm hexagonal hole scaffold(1H-IPC),the elastic modulus and compressive strength of 1C-IPC increased by 15%and 28%,respectively,which was due to the reduced stress concentration and more uniform stress distribution of 1C-IPC.It shows great potential of architecture design in improving the performance of composites.This study provides architectural design strategy and feasible preparation method for the development of high performance materials.
基金financially supported by the National Natural Science Foundation of China(Nos. 21165016, 21175108, 21265018)the Science and Technology Support Projects of Gansu Province (Nos. 1011GKCA025, 090GKCA036,1208RJZM289)
文摘A novel three-dimensional (3D) layered MoS2@graphene functionalized with nitrogen-doped graphene quantum dots (MoS2@N-GQDs-GR) composites as an enhanced electrochemical hydrogen evolution catalyst. The few layered MoS2 nanoflowers supported on N-GQDs-GR surface were elaborately fabricated by one-pot hydrothermal method, which MoS2 and N-GQDs-GR exist in a bonding manner of Mo-N. In addition, due to the layered MoS2 sheet edge exposes more hydrogen evolution active sites and N-GQDs-GR have high conductivity, the composites exhibit prominent electrocatalytic activity with a low overpotential 99 mV, a small Tafel slope 49.3 mV/dec. Therefore, that the current work will develop HER catalysts may replace Pt.
基金supported by the National Natural Science Foundation of China(No.31772643 and 31272468)the Special Research Funding for Discipline Construction in Sichuan Agricultural University(No.03570126)Adisseo France(18SES533).
文摘Background The skeletal muscle of pigs is vulnerable to oxidative damage,resulting in growth retardation.Selenoproteins are important components of antioxidant systems for animals,which are generally regulated by dietary selenium(Se)level.Here,we developed the dietary oxidative stress(DOS)-inducing pig model to investigate the protective effects of selenoproteins on DOS-induced skeletal muscle growth retardation.Results Dietary oxidative stress caused porcine skeletal muscle oxidative damage and growth retardation,which is accompanied by mitochondrial dysfunction,endoplasmic reticulum(ER)stress,and protein and lipid metabolism disorders.Supplementation with Se(0.3,0.6 or 0.9 mg Se/kg)in form of hydroxy selenomethionine(OH-SeMet)linearly increased muscular Se deposition and exhibited protective effects via regulating the expression of selenotranscriptome and key selenoproteins,which was mainly reflected in lower ROS levels and higher antioxidant capacity in skeletal muscle,and the mitigation of mitochondrial dysfunction and ER stress.What’s more,selenoproteins inhibited DOS induced protein and lipid degradation and improved protein and lipid biosynthesis via regulating AKT/mTOR/S6K1 and AMPK/SREBP-1 signalling pathways in skeletal muscle.However,several parameters such as the activity of GSH-Px and T-SOD,the protein abundance of JNK2,CLPP,SELENOS and SELENOF did not show dose-dependent changes.Notably,several key selenoproteins such as MSRB1,SELENOW,SELENOM,SELENON and SELENOS play the unique roles during this protection.Conclusions Increased expression of selenoproteins by dietary OH-SeMet could synergistically alleviate mitochondrial dysfunction and ER stress,recover protein and lipid biosynthesis,thus alleviate skeletal muscle growth retardation.Our study provides preventive measure for OS-dependent skeletal muscle retardation in livestock husbandry.
基金National Natural Science Foundation of China(Grant No.81302763,81573333)Beijing Natural Science Foundation(Grant No.7144218)
文摘This study was designed to investigate the effect of 002C-3, a derivative of magnolol, on transient cerebral middle occlusion （tMCAO） in a mice model and to identify the underlying mechanisms. 002C-3 （100 and 150 pg/kg, i.v. after ending occlusion） significantly reduced neurological deficit scores, infarct volumes, and brain water contents after 1.5 h MCAO and 24 h reperfusion. 002C-3 （75 150μg/kg） decreased the exudation of Evans blue from brain capillaries. 002C-3 （100 μg/kg） significantly inhibited the activity of MMP-9 and MMP-2 in the injured hemisphere. 002C-3 decreased the expression of autophagy-associated proteins, Beclin-1 and LC3B-Ⅱ, and increased the level of p62 in injured hemisphere. 002C-3 （100 pg/kg） significantly increased the expression of p-CaMKIV and p-HDAC4 in injured hemisphere. In conclusion, 002C-3 shows a neuroprotective effect on tMCAO injury in mice, and its mechanisms may be associated with alleviation of blood-brain barrier damage caused by the activation of MMPs, inhibition of autophagy, and stimulation of calcium signals related to cell survival. These findings suggest that 002C-3 is a neuroprotective agent that acts on multiple pathways.
基金Supported by National Natural Science Foundation of China (Exprimental Study of Relation Between Transit of Dampness Turbidity in Lung,Spleen and Kidney and Adjust and Control of Organic Anion Transportingpolypeptide.No.81072806)
文摘OBJECTIVE： This study investigated how polypeptide 2B1 is involved in regulating and governing dampness in rat models with dampness pattern defined in terms of Traditional Chinese Medicine. METHODS： We randomly divided 48 SPF 10-week-old male Sprague-Dawley （SD） rats into a normal group, normal ＋ Aristolochic acid I （AA-I） for 5 min group, normal ＋ AA-I for 60 min group, dampness pattern group （DS-Group）, dampness pattern ＋ AA-I for 5 rain tern ＋ AA-I for 60 min group, and dampness pat- group. Groups were then treated accordingly. We took out the lung, stom- ach, liver, spleen, kidney, large intestine, and small intestine tissues to detect gene and protein expres- sion of organic anion transporter polypeptide 2B1 （OATP2B1）. RESULTS= Gene expression of OATP2B1 in spleen, kidney, and small intestine of rats with dampness pattern was lower than that in normal rats （P〈0.05）. The gene expressions of OATP2B1 in liver, stomach, large intestine, and small intestine were lower than that in control rats at different time points after being stimulated by AA-I （P〈0.05）. CONCLUSION There is coordination among multiple viscera in handling the condition of dampness, and the mechanism underlying the action may rely on regulating the expression of OATP2B1.
基金supported by the open foundation of State Key Laboratory of Chemical Engineering (SKL-ChE-18B03)the Municipal Science and Technology Commission of Tianjin (No. 2009ZCKFGX01900)
文摘A cold-model vertical multi-tube circulating fluidized bed evaporator was designed and built to conduct a visualization study on the pressure drop of a liquid–solid two-phase flow and the corresponding particle distribution.Water and polyformaldehyde particle(POM)were used as the liquid and solid phases,respectively.The effects of operating parameters such as the amount of added particles,circulating flow rate,and particle size were systematically investigated.The results showed that the addition of the particles increased the pressure drop in the vertical tube bundle.The maximum pressure drop ratios were 18.65%,21.15%,18.00%,and 21.15%within the experimental range of the amount of added particles for POM1,POM2,POM3,and POM4,respectively.The pressure drop ratio basically decreased with the increase in the circulating flow rate but fluctuated with the increase in the amount of added particles and particle size.The difference in pressure drop ratio decreased with the increase in the circulating flow rate.As the amount of added particles increased,the difference in pressure drop ratio fluctuated at low circulating flow rate but basically decreased at high circulating flow rate.The pressure drop in the vertical tube bundle accounted for about 70%of the overall pressure drop in the up-flow heating chamber and was the main component of the overall pressure within the experimental range.Three-dimensional phase diagrams were established to display the variation ranges of the pressure drop and pressure drop ratio in the vertical tube bundle corresponding to the operating parameters.The research results can provide some reference for the application of the fluidized bed heat transfer technology in the industry.
基金supported partly by the National Natural Science Foundation of China(No.31772643)the Special Research Funding for Discipline Construction in Sichuan Agricultural University(No.03570126).
文摘Background:Chronic heat stress(CHS)disrupts hepatic metabolic homeostasis and jeopardizes product quality of pigs.Selenium(Se)may regulate the metabolic state through affect selenoprotein.Thus,we investigate the protective effect of dietary hydroxy-4-methylselenobutanoic acid(HMSeBA)on CHS induced hepatic metabolic disorder in growing pigs,and the corresponding response of selenoprotein.Methods:Forty crossbreed growing pigs were randomly assigned to five groups:control group raised in the thermoneutral environment(22±2℃)with basal diet;four CHS groups raised in hyperthermal condition(33±2℃)with basal diet and supplied with 0.0,0.2,0.4,and 0.6 mg Se/kg HMSeBA,respectively.The trial lasted 28 d.The serum biochemical,hepatic metabolism related enzyme,protein and gene expression and 25 selenoproteins in liver tissue were determined by real-time PCR,ELISA and western blot.Results:CHS significantly increased the rectal temperature,respiration rate,serum aspartate aminotransferase(AST)and low-density lipoprotein cholesterol(LDL-C)of pigs,up-regulated hepatic heat shock protein 70(HSP70)and induced lower liver weight,glycogen content,hepatic glucokinase and glutathione peroxidase(GSH-Px).The CHSinduced liver metabolic disorder was associated with the aberrant expression of 6 metabolism-related gene and 11 selenoprotein encoding genes,and decreased the protein abundance of GCK,GPX4 and SELENOS.HMSeBA improved anti-oxidative capacity of liver.0.4 or 0.6 mg Se/kg HMSeBA supplementation recovered the liver weight,glycogen content and rescue of mRNA abundance of genes related to metabolism and protein levels of GCK.HMSeBA supplementation changed expressions of 15 selenoprotein encoding genes,and enhanced protein expression of GPX1,GPX4 and SELENOS in the liver affected by CHS.CHS alone showed no impact while HMSeBA supplementation increased protein levels of p-AMPKαin the liver.Conclusions:In summary,HMSeBA supplementation beyond nutrient requirement mitigates CHS-induced hepatic metabolic disorder,recovered the liver glycogen content and the processes that are associated with the activation of AMPK signal and regulation of selenoproteins in the liver of growing pigs.
基金the Creative Research Group Program of Natural Science Foundation of Hubei Province(2022CFA021)the China Postdoctoral Science Foundation(2022M720895)+1 种基金the National Natural Science Foundation of China(3210011 and 32200132)the Natural Science Foundation of Hubei Province,China(2017CFB535).
文摘COVID-19 has become a global public health crisis since its outbreak in China in December 2019.Currently there are few clinically effective drugs to combat SARS-CoV-2 infection.The main protein(M^(pro)),papain-like protease(PL^(pro))and RNA-dependent RNA polymerase(RdRp)of SARS-CoV-2 are involved in the viral replication,and might be prospective targets for anti-coronavirus drug development.Here,we investigated the antiviral activity of oridonin,a natural small-molecule compound,against SARS-CoV-2 infection in vitro.The time-of-addition analysis showed that oridonin efficiently inhibited SARS-CoV-2 infection by interfering with the genome replication at the post-entry stage.Mechanistically,the inhibition of viral replication by oridonin depends on the oxidation activity ofα,β-unsaturated carbonyl.Further experiments showed that oridonin not only effectively inhibited SARS-CoV-2 Mpro activity,but also had some inhibitory effects on PLpro-mediated deubiquitinating and viral polymerase-catalyzed RNA elongation activities at high concentrations.In particular,oridonin could inhibit the bat SARS-like CoV and the newly emerged SARS-CoV-2 omicron variants(BA.1 and BA.2),which highlights its potential as a pan-coronavirus antiviral agent.Overall,our data provide strong evidence that oridonin is an efficient antiviral agent against SARS-CoV-2 infection.
基金This work was supported in part by the National Key R&D Program of China 2021YFE0110500in part by the National Natural Science Foundation of China under Grant 62062021in part by the Guiyang Scientific Plan Project[2023]48-11.
文摘Unsupervised methods based on density representation have shown their abilities in anomaly detection,but detection performance still needs to be improved.Specifically,approaches using normalizing flows can accurately evaluate sample distributions,mapping normal features to the normal distribution and anomalous features outside it.Consequently,this paper proposes a Normalizing Flow-based Bidirectional Mapping Residual Network(NF-BMR).It utilizes pre-trained Convolutional Neural Networks(CNN)and normalizing flows to construct discriminative source and target domain feature spaces.Additionally,to better learn feature information in both domain spaces,we propose the Bidirectional Mapping Residual Network(BMR),which maps sample features to these two spaces for anomaly detection.The two detection spaces effectively complement each other’s deficiencies and provide a comprehensive feature evaluation from two perspectives,which leads to the improvement of detection performance.Comparative experimental results on the MVTec AD and DAGM datasets against the Bidirectional Pre-trained Feature Mapping Network(B-PFM)and other state-of-the-art methods demonstrate that the proposed approach achieves superior performance.On the MVTec AD dataset,NF-BMR achieves an average AUROC of 98.7%for all 15 categories.Especially,it achieves 100%optimal detection performance in five categories.On the DAGM dataset,the average AUROC across ten categories is 98.7%,which is very close to supervised methods.
基金supported partly by the National Natural Science Foundation of China(No.31772643)the Special Research Funding for Discipline Construction in Sichuan Agricultural University(No.03570126)。
文摘Background At presenti heat stress(HS)has become a key factor that impairs broiler breeding industry,which causes growth restriction and poor meat quality of broilers.S elenium(Se)is an excellent antioxidant and plays a unique role in meat quality improvement.Recent years,nano-selenium(NanoSe)has received tremendous attention in livestock production,due to its characteristic and good antibacterial performance in vitro.Here,we developed the heat stressed-broiler model to investigate the protective effects of NanoSe on growth performance and meat quality of broilers and compare whether there are differences with that of other Se sources(Sodium selenite,SS;Selenoyeast,SeY;Selenomethioninec SeMet).Results HS jeopardized the growth performance and caused poor meat quality of breast muscle in broilers,which were accompanied by lowered antioxidant capacity,increased glycolysis,increased anaerobic metabolism of pyruvate,mitochondrial stress and abnormal mitochondrial tricarboxylic acid(TCA)cycle.All Se sources supplementation exhibited protective effects,which increased the Se concentration and promoted the expression of selenoproteins,improved the mitochondrial homeostasis and the antioxidant capacity,and promoted the TCA cycle and the aerobic metabolism of pyruvate,thus improved the breast muscle meat quality of broilers exposed to HS.However,unlike the other three Se sources,the protective effect of NanoSe on meat quality of heat stressed-broilers was not ideal,which exhibited limited impact on the pH value,drip loss and cooking loss of the breast muscle.Compared with the other Se sources,broilers received NanoSe showed the lowest levels of slow MyHC,the highest levels of fast MyHC and glycogen,the highest mRNA levels of glycolysis-related genes(PFKM and PKM),the highest protein expression of H5P60 and CLPP,and the lowest enzyme activities of GSH-Px,citroyl synthetase(CS)and isocitrate dehydrogenase(ICD)in breast muscle.Consistent with the SS,the Se deposition in breast muscle of broilers received NanoSe was lower than that of broilers received SeY or SeMet.Besides,the regulatory effciency of NanoSe on the expression of key selenoproteins(such as SELENOS)in breast muscle of heat stressed-broilers was also worse than that of other Se Sources.Conclusion Through comparing the meat quality,Se deposition,muscle fiber type conversion,glycolysis,mitochondrial homeostasis,and hond rial TCA cycle-related indicators of breast muscle in heat stressed broilers,we found that the protective effects of organic Se(SeY and SeMet)are better than that of inorganic Se(SS)and NanoSe.As a new Se source,though Nanose showed some protective effect on breast muscle meat quality of heat stressed broilers,the protective effect of NanoSe is not ideal,compared with other Se sources.
基金funded by the National Natural Science Foundation of China[grant number 42271318,42271354,41971402]the Science and Technology Project of Department of Natural Resources of Hubei Province[grant number ZRZY2023KJ41]+1 种基金the National Key Research and Development Program of China[grant number 2018YFC1506506]the ESA-MOST Dragon Program[grant number 58815],and the LIESMARS Special Research Funding.
文摘Recent research shows that China is experiencing significant greening,with afforestation initiatives being the main cause.Quantitative calculation of vegetation change influencing factors and evaluation of the contribution of afforestation to vegetation greening in China are critical to coping with climate change and improving the implementation and efficacy of forestry projects.We investigated the temporal and spatial dynamics of the Normalized Difference Vegetation Index(NDVI)from 1982 to 2020,and quantified the contribution of afforestation initiatives,a typical human activity,to the dynamic changes of vegetation.The results showed that NDVI in China has primarily increased in the last 39 years.57%of the pixels increased,27%were stable and unchanged,and 16%decreased.Climate change was responsible for 72.34%of vegetation restoration,while human activities were responsible for 27.36%of vegetation restoration,according to residual analysis.In the future,only 14%of the regions showed continuous growth of the NDVI,while the remaining regions showed obvious antipersistence(59%will go from increasing to decreasing,and 22%will go from decreasing to increasing).The contribution of climate factors to vegetation change will decrease in the future,and human activities will become more complex.Except for Huaihe River and Taihu Lake(SPHRTL),other forestry projects showed an increasing trend of NDVI after the implementation of ecological engineering.However,due to differences in climate conditions and ecological engineering implementation,there are differences in the benefits of forestry projects.Some forestry project areas still have obvious vegetation degradation,and appropriate forestry management is necessary.This work provides a quantitative analysis of vegetation change and its driving factors in China,which will help to cope with future climate change and provide a reference for the implementation and management of ecological projects.
基金supported by National Natural Science Foundation of China(61364017,60804066)The Scientific and Technological Project of Education Department of Jiangxi Province(KJLD12068)Natural Science Foundation of Jiangxi Province(20132BAB201039)
文摘Objective: To explore the significance of dual-energy CT non-linear fusion technique in improving the quality of CTA image of renal cancer. Methods: The CTA images of 100 patients who had been confirmed by pathology as renal cancer were collected and were randomly divided into experimental group and control group with 50 cases respectively. The two groups of patients were treated with iodine concentration of 300 mg/ml and 350 mg/ml non-ionic contrast agent, with a dosage of 1.5 ml/kg and an injection rate of 4 ml/s. The contrast agent intelligently tracking method was adopted bolus. The control group used the conventional CTA scanning, with a reference tube voltage/tube current of 100 kv/ref150 mas. The experimental group adopted the double energy scanning, with ball tube A and ball tube B. The reference tube voltage/tube current was 100 kv/ref250 mas and sn150 kv/ref125 mas respectively. The images of the experimental group were non-linear fused to obtain the Mono+ 55 kev single-energy images. The CT value, SNR contrast ratio of the abdominal aorta, renal artery and tumor tissue of the experimental group images and the 100 KV images and the Mono+ 55 kev images of the control group were compared. The objective evaluation and subjective evaluation of the image quality of the three groups of images was performed. Results: The results showed that the 100 kV images of the experimental group were statistically different from those of the control group (P05) in CT value, SNR and CNR (P 0.05). And there was no statistically significant difference between the non-linear fusion single-energy Mono+ 55 kev images and the control group images in CT value, SNR and CNR (P > 0.05). The subjective evaluation of image quality showed that there was no significant difference between Mono+ 55 kev images and control group images, and the quality of Mono+ 55 kev images was higher than that of experimental group 100 kV images. Conclusion: The dual-energy CT non-linear fusion technique can improve the quality of CTA image in patients with renal cancer, and it is possible to obtain high quality CTA images with low iodine concentration contrast agent.
文摘It is generally believed that a major cause of motor dysfunction is the impairment in neural network that controls movement. But little is known about the underlying mechanisms of the impairment in cortical control or in the neural connections between cortex and muscle that lead to the loss of motor ability. So understanding the functional connection between motor cortex and effector muscle is of utmost importance. Previous study mostly relied on cross-correlation, coherence functions or model based approaches such as Granger causality or dynamic causal modeling. In this work the information transfer index (ITI) was introduced to describe the information flows between motor cortex and muscle. Based on the information entropy the ITI can detect both linear and nonlinear interaction between two signals and thus represent a very comprehensive way to define the causality strength. The applicability of ITI is investigated based on simulations and electroencephalogram (EEG), surface electromyography (sEMG) recordings in a simple motor task.
基金the Foundation of Science and Technology Department of Zhejiang Province,China,No. 2007C33049Fund for Fostering Talents in Basic Science of the National Natural Science Foundation of China,No. J0710043
文摘Spinal muscular atrophy （SMA） is an autosomal recessive neuromuscular disorder characterized by degeneration and loss of anterior horn cells in the spinal cord and brain stem nuclei, leading to progressive limb and trunk paralysis and muscular atrophy. Depending on the age of onset and maximum muscular function achieved, SMA is recognized as SMA1, SMA2, SMA3 or SMA4, and most patients have a deletion or truncation of the survival motor neuron 1 （SMN1） gene. In this report, we present a patient with a mild SMA phenotype, SMA3, and define his genetic abnormality. Tetra-primer amplification refractory mutation system PCR combined with restriction fragment length polymorphism analysis and array comparative genomic hybridization were used to determine the genetic variations in this patient. A 500 kb deletion in chromosome 5q13.2, including homozygous deletion of neuronal apoptosis inhibitory protein, and heterozygous deletion of occludin and B-double prime 1 was identified. This SMA region deletion did not involve SMN, indicating that SMN was likely to function normally. The phenotype was dependent of the large deletion and neuronal apoptosis inhibitory protein, occludin and B-double prime 1 may be candidate genes for SMA3.
