BACKGROUND: Portal vein thrombosis (PVT) is due to many risk factors, but its pathogenesis is still not clearly understood. To identify the risk factors for PVT, we analyzed the clinical characteristics and complicati...BACKGROUND: Portal vein thrombosis (PVT) is due to many risk factors, but its pathogenesis is still not clearly understood. To identify the risk factors for PVT, we analyzed the clinical characteristics and complications associated with PVT in cir-rhotic patients. METHODS: We studied patients with liver cirrhosis who were admitted to our unit from April 2009 to December 2014. The patients were divided into the PVT and non-PVT groups, and were compared by variables including gender, age, the etiology of cirrhosis, stage of cirrhosis, complications, imaging, and treatment. RESULTS: PVT was found in 45 (9.8%) of 461 cirrhotic pa-tients admitted to our hospital. Most patients (45.9%) had hepatitis B virus (HBV)-related cirrhosis, with a similar dis-tribution of etiologies between the groups. However, there was no positive relationship between PVT and etiologies of cirrhosis. Most patients (71.5%) were in the stage of hepatic decompensation. No statistically signiifcant differences were found in complications including esophageal varices, ascites, and hepatic encephalopathy between the groups. However, there was a signiifcant positive correlation between hepatocel-lular carcinoma (HCC) and PVT (P<0.01). In 30 patients with PVT, thrombosis occurred in the portal vein and/or portal branches, 37.8% were diagnosed on ultrasound. CONCLUSIONS: The incidence of PVT was 9.8%, mainly in patients with HBV-related cirrhosis. The development of PVT was associated with the severity of liver disease and HCC.展开更多
In Pakistan more than 10 million people are living with Hepatitis C virus (HCV), with high morbidity and mortality. This article reviews the prevalence, genotypes and factors associated with HCV infection in the Pakis...In Pakistan more than 10 million people are living with Hepatitis C virus (HCV), with high morbidity and mortality. This article reviews the prevalence, genotypes and factors associated with HCV infection in the Pakistani population. A literature search was performed by using the keywords; HCV prevalence, genotypes and risk factors in a Pakistani population, in Pubmed, PakMediNet and Google scholar. Ninetyone different studies dating from 1994 to May 2009 were included in this study, and weighted mean and standard error of each population group was calculated. Percentage prevalence of HCV was 4.95% ± 0.53% in the general adult population, 1.72% ± 0.24% in the pediatric population and 3.64% ± 0.31% in a young population applying for recruitment, whereas a very high 57% ± 17.7% prevalence was observed in injecting drug users and 48.67% ± 1.75% in a multi-transfused population. Most prevalent genotype of HCV was 3a. HCV prevalence was moderate in the general population but very high in injecting drug users and multi-transfused populations. This data suggests that the major contributing factors towards increased HCV prevalence include unchecked blood transfusions and reuse of injection syringes. Awareness programs are required to decrease the future burden of HCV in the Pakistani population.展开更多
Phytoremediation is a valuable technology for mitigating soil contamination in agricultural lands,but phytoremediation without economic revenue is unfeasible for land owners and farmers.The use of crops with high biom...Phytoremediation is a valuable technology for mitigating soil contamination in agricultural lands,but phytoremediation without economic revenue is unfeasible for land owners and farmers.The use of crops with high biomass and bioenergy for phytoremediation is a unique strategy to derive supplementary benefits along with remediation activities.Sunflower(Helianthus annuus L.)is a high-biomass crop that can be used for the phytoremediation of polluted lands with additional advantages(biomass and oil).In this study,40 germplasms of sunflower were screened in field conditions for phytoremediation with the possibility for oil and meal production.The study was carried out to the physiological maturity stage.All studied germplasms mopped up substantial concentrations of Pb,with maximum amounts in shoot>root>seed respectively.The phytoextraction efficiency of the germplasm was assessed in terms of the Transfer factor(TF),Metal removal efficiency(MRE)and Metal extraction ratio(MER).Among all assessed criteria,GP.8585 was found to be most appropriate for restoring moderately Pb-contaminated soil accompanied with providing high biomass and high yield production.The Pb content in the oil of GP.8585 was below the Food safety standard of China,with 59.5% oleic acid and 32.1% linoleic acid.Moreover,amino acid analysis in meal illustrated significant differences among essential and nonessential amino acids.Glutamic acid was found in the highest percentage(22.4%),whereas cysteine in the lowest percentage(1.3%).Therefore,its efficient phytoextraction ability and good quality edible oil and meal production makes GP.8585 the most convenient sunflower germplasm for phytoremediation of moderately Pb-contaminated soil,with fringe benefits to farmers and landowners.展开更多
Lithium-sulfur(Li-S) battery is one of the best candidates for the next-generation energy storage system due to its high theoretical capacity(1675 mA h-1),low cost and environment friendliness.However,lithium(Li) dend...Lithium-sulfur(Li-S) battery is one of the best candidates for the next-generation energy storage system due to its high theoretical capacity(1675 mA h-1),low cost and environment friendliness.However,lithium(Li) dendrites formation and polysulfide shuttle effect are two major challenges that limit the commercialization of Li-S batteries.Here we design a facile bifunctional interlayer of gelatin-based fibers(GFs),aiming to protect the Li anode surface from the dendrites growth and also hinder the polysulfide shuttle effect.We reveal that the 3D structural network of GFs layer with abundant polar sites helps to homogenize Li-ion flux,leading to uniform Li-ion deposition.Meanwhile,the polar moieties also immobilize the lithium polysulfides and protect the Li metal from the side-reaction.As a result,the anodeprotected batteries have shown significantly enhanced performance.A high coulombic efficiency of 96% after 160 cycles has been achieved in the Li-Cu half cells.The Li-Li symmetric cells exhibit a prolonged lifespan for 800 h with voltage hysteresis(10 mV).With the as-prepared GFs layer,the Li-S battery shows approximately 14% higher capacity retention than the pristine battery at 0.5 C after 100 cycles.Our work presents that this gelatin-based bi-functional interlayer provides a viable strategy for the manufacturing of advanced Li-S batteries.展开更多
Diabetic retinopathy(DR)is the most common cause of visual loss among working age individuals.Diabetic macular edema(DME)is an important complication of DR that affects around one third of the patients with DR.Several...Diabetic retinopathy(DR)is the most common cause of visual loss among working age individuals.Diabetic macular edema(DME)is an important complication of DR that affects around one third of the patients with DR.Several treatments have been approved for DME ranging from blood pressure and glycemic control to photocoagulation and more recently the use of vascular endothelial growth factor(VEGF)antagonists.The index review discusses aflibercept(EYLEA-Regeneron Pharmaceuticals,Inc.,Tarrytown,New York,NY,and Bayer Healthcare Pharmaceuticals,Berlin,Germany)in the context of other VEGF antagonists currently available for the treatment of DME.A systematic search of literature was conducted on PubMed,Scopus,and Google Scholar with no limitation on language or year of publication.Pre-clinical studies of aflibercept have shown a higher affinity of this molecule for vascular endothelial growth factor A(VEGF-A)along with a longer duration of action as compared to other VEGF antagonists.Recent clinical trials have shown visual outcome results for aflibercept to be similarly favorable as compared to other available agents with the added benefit of fewer required injections and less frequent monitoring.Aflibercept presents a potential exciting new addition to the armamentarium of current VEGF antagonists available for the treatment of DME and other retinal vascular diseases.However,further studies are indicated to confirm the role,safety,and efficacy of aflibercept for DME.展开更多
In this study,a few Fe-based amorphous matrix composite coatings reinforced with various portions(4,8 and16 vol.%) of 31 6L stainless steel powders have been successfully produced through high velocity oxy-fuel(HVOF) ...In this study,a few Fe-based amorphous matrix composite coatings reinforced with various portions(4,8 and16 vol.%) of 31 6L stainless steel powders have been successfully produced through high velocity oxy-fuel(HVOF) spraying.The microstructure of the composite coatings was systematically characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM) and transmission electron microscopy(TEM).The main structure of composite coatings remained amorphous while 31 6L stainless steel splats were distributed homogeneously in the amorphous matrix and well connected with surrounding amorphous phase.Bonding strength of coatings to the substrate was determined by 'pull-off' tensile tests.The results revealed that the31 6L stainless steel phase effectively improved the bonding strength of amorphous coatings,which is mainly contributed by the strong metallurgical bonding between stainless steel and amorphous splats.The addition of31 6L stainless steel also enhanced the ductility and fracture resistance of the coatings due to the ductile stainless steel phases,which can arrest crack propagation and increase energy dissipation.展开更多
Lane-changing is performed either to follow the route to a planned destination(i.e.,mandatory lane-changing)or to achieve better driving conditions(i.e.,discretionary lane-changing).A connected environment is expected...Lane-changing is performed either to follow the route to a planned destination(i.e.,mandatory lane-changing)or to achieve better driving conditions(i.e.,discretionary lane-changing).A connected environment is expected to assist during lane-changing manoeuvres,but it is not known well how driving aids in a connected environment assist lane-changing execution.As such,this study investigates the impact of a connected environment on lanechanging execution time during mandatory and discretionary lane-changing manoeuvres.To this end,this study designed an advanced driving simulator experiment where 78 drivers performed these manoeuvres on a simulated motorway in three randomised driving conditions.The conditions were baseline(without driving aids),a fully functioning connected environment with a perfect supply of driving aids,and an impaired connected environment with delayed driving aids.The lane-changing execution time has been modelled by a random parameters hazard-based duration modelling approach,which accounts for the panel nature of data and captures the unobserved heterogeneity.Results suggest that,compared to the baseline condition(i.e.,a non-connected environment),most of the drivers in the connected environment take more time to complete their lane-changing manoeuvres,indicating drivers’safer lane-changing execution behaviour in the connected environment.The communication delay driving condition has been found to have more deteriorating effects on mandatory lanechanging manoeuvres than discretionary lane-changing manoeuvres.This study concludes that(i)the connected environment increases safety margin during both lane-changing manoeuvres,and(ii)a higher magnitude of safety margin is observed during mandatory lane-changing manoeuvres whereby drivers have a higher need for assistance.展开更多
Herein, we report a bottom-up solvothermal route to synthesize a flexible, highly efficient MoS2@SWNT electrocatalyst for hydrogen evolution reactions （HER）. Characterization revealed that branchqike MoS2 nanosheets...Herein, we report a bottom-up solvothermal route to synthesize a flexible, highly efficient MoS2@SWNT electrocatalyst for hydrogen evolution reactions （HER）. Characterization revealed that branchqike MoS2 nanosheets containing sulfur- rich sites were in situ uniformly dispersed on free-standing single-walled carbon nanotube （SWNT） film, which could expose more unsaturated sulfur atoms, allowing excellent electrical contact with active sites. The flexible catalyst exhibited excellent HER performance with a low overpotential （-150 mV at 10 ma/cm2） and small Tafel slope （4l mV/dec）. To further explain the improved performance, the local electronic structure was investigated by X-ray absorption near-edge structure （XANES） analysis, proving the presence of unsaturated sulfur atoms and strong electronic coupling between MoS2 and SWNT. This study provides an in-situ synthetic route to create new multifunctional flexible hybridized catalysts and useful insights into the relationships electronic structure, and properties among the catalyst microstructure,展开更多
Experimental and analytical investigation is conducted to explore the effects of stitching on plain （without hole） and open-hole compressive and tensile strength of uniweave T300/QY9512 laminates under different env...Experimental and analytical investigation is conducted to explore the effects of stitching on plain （without hole） and open-hole compressive and tensile strength of uniweave T300/QY9512 laminates under different environmental conditions （20 ℃/dry and wet, 150 ℃/dry and wet）. Strength performance of stitched composite laminates is also studied using finite element analysis （FEA） model and compared with the experimental results to validate the model. It is found that under similar environmental conditions, the open-hole compressive strength of stitched laminate is decreased and open-hole tensile strength increased as compared to the unstitched laminates. Predicted tensile and compressive strengths are found to be in a good agreement with the test results and the relative error in all cases is less than 15%.展开更多
Newcastle disease (ND) virus is a leading threat to commercial and domestic poultry in Pakistan. The virus infects and constitutes irreversible impairment to the nervous system, damages the respiratory system, and mar...Newcastle disease (ND) virus is a leading threat to commercial and domestic poultry in Pakistan. The virus infects and constitutes irreversible impairment to the nervous system, damages the respiratory system, and marks severe gastrointestinal lesions leading to heavy mortality in short-living birds and substantial losses in layers and breeders. The continuous emergence and evolution of the virus made it inclined to evade the humoral response and indirectly the circumvention of artificial active immunization. Newcastle disease is caused by the orthoavula genus of the paramyxoviridae family and has shown high genetic diversity even in their genotypes while information regarding enzootic trends of the virus is scanty in Pakistan. A total of 40 tracheal samples of NDV were collected from different commercial broiler farms and 11 isolates of NDV were identified. In the current study, we determined the genetic diversity of the Newcastle disease virus based on the partial sequencing of the fusion protein gene available in the NCBI database. Genetic analysis showed that seven isolates belonged to class I genotype VII and four belonged to class II genotype II. Interestingly, two isolates had epidemiological connections with vaccine-like class II genotype II. Our findings, concerning the recent outbreaks of class I genotype VII and class II genotype II of NDV in vaccinated commercial flocks, suggest possible potential partial mutations in the fusion protein gene. Genetic diversity and formation of the new cleavage site in an important neutralizing protein of wild strain are linked with the potency of artificial active immunization and a major cause of vaccine failure.展开更多
Background: Cut-throat injury is a potentially fatal condition that may be associated with serious morbidity and mortality. The neck region is particularly at risk of serious injuries due to the location of vital stru...Background: Cut-throat injury is a potentially fatal condition that may be associated with serious morbidity and mortality. The neck region is particularly at risk of serious injuries due to the location of vital structures, including nerves, viscera, and major vessels. Although cut-throat injury is said to be rare in children, its occurrence has been reported in some series. Management of this condition requires a multidisciplinary approach for a better outcome. Aim: The aim of this report is to highlight the successful management of an alarming case of severe cut-throat injury with associated laryngeal injury in a child. Case presentation: A 12-year-old boy presented with a cut-throat following an assault by an unknown person. Examination revealed an acutely ill child, conscious but pale. He sustained a deep transverse laceration that transected the thyroid cartilage, exposing the laryngeal cavity. An assessment of Zone II penetrating neck injury was made. He was resuscitated, and had emergency neck exploration, tracheostomy, and repair of the injuries. The patient was followed up for 6 months, and had a good voice outcome, with no significant complication. Conclusion: Cut-throat injury is rare in children. But it is a potentially life-threatening condition. It is therefore important to recognize this entity and develop effective protocol of management in our environment.展开更多
Hyperparameter tuning is a key step in developing high-performing machine learning models, but searching large hyperparameter spaces requires extensive computation using standard sequential methods. This work analyzes...Hyperparameter tuning is a key step in developing high-performing machine learning models, but searching large hyperparameter spaces requires extensive computation using standard sequential methods. This work analyzes the performance gains from parallel versus sequential hyperparameter optimization. Using scikit-learn’s Randomized SearchCV, this project tuned a Random Forest classifier for fake news detection via randomized grid search. Setting n_jobs to -1 enabled full parallelization across CPU cores. Results show the parallel implementation achieved over 5× faster CPU times and 3× faster total run times compared to sequential tuning. However, test accuracy slightly dropped from 99.26% sequentially to 99.15% with parallelism, indicating a trade-off between evaluation efficiency and model performance. Still, the significant computational gains allow more extensive hyperparameter exploration within reasonable timeframes, outweighing the small accuracy decrease. Further analysis could better quantify this trade-off across different models, tuning techniques, tasks, and hardware.展开更多
This study examines a recently hypothesized black hole,which is a perfect solution of metric-affine gravity with a positive cosmological constant,and its thermodynamic features as well as the Joule-Thomson expansion.W...This study examines a recently hypothesized black hole,which is a perfect solution of metric-affine gravity with a positive cosmological constant,and its thermodynamic features as well as the Joule-Thomson expansion.We develop some thermodynamical quantities,such as volume,Gibbs free energy,and heat capacity,using the entropy and Hawking temperature.We also examine the first law of thermodynamics and thermal fluctuations,which might eliminate certain black hole instabilities.In this regard,a phase transition from unstable to stable is conceivable when the first law order corrections are present.In addition,we study the efficiency of this system as a heat engine and the effect of metric-affine gravity for the physical parameters q_(e),q_(m),κ_(s),κ_(d),and κ_(sh).Further,we study the Joule-Thomson coefficient and inversion temperature,and observe the isenthalpic curves in the Ti−Pi plane.In metric-affine gravity,a comparison is made between a van der Waals fluid and a black hole to study their similarities and differences.展开更多
文摘BACKGROUND: Portal vein thrombosis (PVT) is due to many risk factors, but its pathogenesis is still not clearly understood. To identify the risk factors for PVT, we analyzed the clinical characteristics and complications associated with PVT in cir-rhotic patients. METHODS: We studied patients with liver cirrhosis who were admitted to our unit from April 2009 to December 2014. The patients were divided into the PVT and non-PVT groups, and were compared by variables including gender, age, the etiology of cirrhosis, stage of cirrhosis, complications, imaging, and treatment. RESULTS: PVT was found in 45 (9.8%) of 461 cirrhotic pa-tients admitted to our hospital. Most patients (45.9%) had hepatitis B virus (HBV)-related cirrhosis, with a similar dis-tribution of etiologies between the groups. However, there was no positive relationship between PVT and etiologies of cirrhosis. Most patients (71.5%) were in the stage of hepatic decompensation. No statistically signiifcant differences were found in complications including esophageal varices, ascites, and hepatic encephalopathy between the groups. However, there was a signiifcant positive correlation between hepatocel-lular carcinoma (HCC) and PVT (P<0.01). In 30 patients with PVT, thrombosis occurred in the portal vein and/or portal branches, 37.8% were diagnosed on ultrasound. CONCLUSIONS: The incidence of PVT was 9.8%, mainly in patients with HBV-related cirrhosis. The development of PVT was associated with the severity of liver disease and HCC.
基金Supported by Higher Education Commission of Pakistan Grant No.829Pak-US Science and Technology Cooperative Program,entitled "HCV management in Pakistan"
文摘In Pakistan more than 10 million people are living with Hepatitis C virus (HCV), with high morbidity and mortality. This article reviews the prevalence, genotypes and factors associated with HCV infection in the Pakistani population. A literature search was performed by using the keywords; HCV prevalence, genotypes and risk factors in a Pakistani population, in Pubmed, PakMediNet and Google scholar. Ninetyone different studies dating from 1994 to May 2009 were included in this study, and weighted mean and standard error of each population group was calculated. Percentage prevalence of HCV was 4.95% ± 0.53% in the general adult population, 1.72% ± 0.24% in the pediatric population and 3.64% ± 0.31% in a young population applying for recruitment, whereas a very high 57% ± 17.7% prevalence was observed in injecting drug users and 48.67% ± 1.75% in a multi-transfused population. Most prevalent genotype of HCV was 3a. HCV prevalence was moderate in the general population but very high in injecting drug users and multi-transfused populations. This data suggests that the major contributing factors towards increased HCV prevalence include unchecked blood transfusions and reuse of injection syringes. Awareness programs are required to decrease the future burden of HCV in the Pakistani population.
基金supported by Zhejiang Science and Technology Bureau(No.2018C02029)the National Natural Science Foundation of China(Nos.41721001 and 31872956)+1 种基金Ministry of Science and Technology of China(No.2016YFD0800805)the Fundamental Research Funds for the Central Universities
文摘Phytoremediation is a valuable technology for mitigating soil contamination in agricultural lands,but phytoremediation without economic revenue is unfeasible for land owners and farmers.The use of crops with high biomass and bioenergy for phytoremediation is a unique strategy to derive supplementary benefits along with remediation activities.Sunflower(Helianthus annuus L.)is a high-biomass crop that can be used for the phytoremediation of polluted lands with additional advantages(biomass and oil).In this study,40 germplasms of sunflower were screened in field conditions for phytoremediation with the possibility for oil and meal production.The study was carried out to the physiological maturity stage.All studied germplasms mopped up substantial concentrations of Pb,with maximum amounts in shoot>root>seed respectively.The phytoextraction efficiency of the germplasm was assessed in terms of the Transfer factor(TF),Metal removal efficiency(MRE)and Metal extraction ratio(MER).Among all assessed criteria,GP.8585 was found to be most appropriate for restoring moderately Pb-contaminated soil accompanied with providing high biomass and high yield production.The Pb content in the oil of GP.8585 was below the Food safety standard of China,with 59.5% oleic acid and 32.1% linoleic acid.Moreover,amino acid analysis in meal illustrated significant differences among essential and nonessential amino acids.Glutamic acid was found in the highest percentage(22.4%),whereas cysteine in the lowest percentage(1.3%).Therefore,its efficient phytoextraction ability and good quality edible oil and meal production makes GP.8585 the most convenient sunflower germplasm for phytoremediation of moderately Pb-contaminated soil,with fringe benefits to farmers and landowners.
基金supported by the National Natural Science Foundation of China (No. 51861165101)。
文摘Lithium-sulfur(Li-S) battery is one of the best candidates for the next-generation energy storage system due to its high theoretical capacity(1675 mA h-1),low cost and environment friendliness.However,lithium(Li) dendrites formation and polysulfide shuttle effect are two major challenges that limit the commercialization of Li-S batteries.Here we design a facile bifunctional interlayer of gelatin-based fibers(GFs),aiming to protect the Li anode surface from the dendrites growth and also hinder the polysulfide shuttle effect.We reveal that the 3D structural network of GFs layer with abundant polar sites helps to homogenize Li-ion flux,leading to uniform Li-ion deposition.Meanwhile,the polar moieties also immobilize the lithium polysulfides and protect the Li metal from the side-reaction.As a result,the anodeprotected batteries have shown significantly enhanced performance.A high coulombic efficiency of 96% after 160 cycles has been achieved in the Li-Cu half cells.The Li-Li symmetric cells exhibit a prolonged lifespan for 800 h with voltage hysteresis(10 mV).With the as-prepared GFs layer,the Li-S battery shows approximately 14% higher capacity retention than the pristine battery at 0.5 C after 100 cycles.Our work presents that this gelatin-based bi-functional interlayer provides a viable strategy for the manufacturing of advanced Li-S batteries.
文摘Diabetic retinopathy(DR)is the most common cause of visual loss among working age individuals.Diabetic macular edema(DME)is an important complication of DR that affects around one third of the patients with DR.Several treatments have been approved for DME ranging from blood pressure and glycemic control to photocoagulation and more recently the use of vascular endothelial growth factor(VEGF)antagonists.The index review discusses aflibercept(EYLEA-Regeneron Pharmaceuticals,Inc.,Tarrytown,New York,NY,and Bayer Healthcare Pharmaceuticals,Berlin,Germany)in the context of other VEGF antagonists currently available for the treatment of DME.A systematic search of literature was conducted on PubMed,Scopus,and Google Scholar with no limitation on language or year of publication.Pre-clinical studies of aflibercept have shown a higher affinity of this molecule for vascular endothelial growth factor A(VEGF-A)along with a longer duration of action as compared to other VEGF antagonists.Recent clinical trials have shown visual outcome results for aflibercept to be similarly favorable as compared to other available agents with the added benefit of fewer required injections and less frequent monitoring.Aflibercept presents a potential exciting new addition to the armamentarium of current VEGF antagonists available for the treatment of DME and other retinal vascular diseases.However,further studies are indicated to confirm the role,safety,and efficacy of aflibercept for DME.
基金financially supported by the National Natural Science Foundation of China (Grant Nos. 51271081 and 51301072)partially supported by the Key Fundamental Research Project from Shenzhen Research Council (No. JC201105170745A)
文摘In this study,a few Fe-based amorphous matrix composite coatings reinforced with various portions(4,8 and16 vol.%) of 31 6L stainless steel powders have been successfully produced through high velocity oxy-fuel(HVOF) spraying.The microstructure of the composite coatings was systematically characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM) and transmission electron microscopy(TEM).The main structure of composite coatings remained amorphous while 31 6L stainless steel splats were distributed homogeneously in the amorphous matrix and well connected with surrounding amorphous phase.Bonding strength of coatings to the substrate was determined by 'pull-off' tensile tests.The results revealed that the31 6L stainless steel phase effectively improved the bonding strength of amorphous coatings,which is mainly contributed by the strong metallurgical bonding between stainless steel and amorphous splats.The addition of31 6L stainless steel also enhanced the ductility and fracture resistance of the coatings due to the ductile stainless steel phases,which can arrest crack propagation and increase energy dissipation.
基金partly funded by the Australian Research Council grant DP210102970.
文摘Lane-changing is performed either to follow the route to a planned destination(i.e.,mandatory lane-changing)or to achieve better driving conditions(i.e.,discretionary lane-changing).A connected environment is expected to assist during lane-changing manoeuvres,but it is not known well how driving aids in a connected environment assist lane-changing execution.As such,this study investigates the impact of a connected environment on lanechanging execution time during mandatory and discretionary lane-changing manoeuvres.To this end,this study designed an advanced driving simulator experiment where 78 drivers performed these manoeuvres on a simulated motorway in three randomised driving conditions.The conditions were baseline(without driving aids),a fully functioning connected environment with a perfect supply of driving aids,and an impaired connected environment with delayed driving aids.The lane-changing execution time has been modelled by a random parameters hazard-based duration modelling approach,which accounts for the panel nature of data and captures the unobserved heterogeneity.Results suggest that,compared to the baseline condition(i.e.,a non-connected environment),most of the drivers in the connected environment take more time to complete their lane-changing manoeuvres,indicating drivers’safer lane-changing execution behaviour in the connected environment.The communication delay driving condition has been found to have more deteriorating effects on mandatory lanechanging manoeuvres than discretionary lane-changing manoeuvres.This study concludes that(i)the connected environment increases safety margin during both lane-changing manoeuvres,and(ii)a higher magnitude of safety margin is observed during mandatory lane-changing manoeuvres whereby drivers have a higher need for assistance.
基金We acknowledge the financial support of the National Basic Research Program of China （No. 2014CB848900）, the National Natural Science Foundation of China （Nos. U1232131, U1532112, 11375198, and 11574280）, the Fundamental Research Funds for the Central Universities （No. WK2310000053）, User with Potential from CAS Hefei Science Center （No. 2015HSC-UP020） and Key Laboratory of Advanced Energy Materials Chemistry （Ministry of Education） Nankai University. L. S. thanks the recruitment program of global experts, the CAS Hundred Talent Program. We also thank the Shanghai synchrotron Radiation Facility （14W1, SSRF）, the Beijing Synchrotron Radiation Facility （1W1B and soft-X-ray endstation, BSRF） and the Hefei Synchrotron Radiation Facility （MCD and Photoemission Endstations, NSRL） for help in characterizations.
文摘Herein, we report a bottom-up solvothermal route to synthesize a flexible, highly efficient MoS2@SWNT electrocatalyst for hydrogen evolution reactions （HER）. Characterization revealed that branchqike MoS2 nanosheets containing sulfur- rich sites were in situ uniformly dispersed on free-standing single-walled carbon nanotube （SWNT） film, which could expose more unsaturated sulfur atoms, allowing excellent electrical contact with active sites. The flexible catalyst exhibited excellent HER performance with a low overpotential （-150 mV at 10 ma/cm2） and small Tafel slope （4l mV/dec）. To further explain the improved performance, the local electronic structure was investigated by X-ray absorption near-edge structure （XANES） analysis, proving the presence of unsaturated sulfur atoms and strong electronic coupling between MoS2 and SWNT. This study provides an in-situ synthetic route to create new multifunctional flexible hybridized catalysts and useful insights into the relationships electronic structure, and properties among the catalyst microstructure,
基金National Natural Science Foundation of China(10672009)Basic Science Foundation of Aviation(05B51044)"FanZhou" Youth Scientific Funds(20060501)
文摘Experimental and analytical investigation is conducted to explore the effects of stitching on plain （without hole） and open-hole compressive and tensile strength of uniweave T300/QY9512 laminates under different environmental conditions （20 ℃/dry and wet, 150 ℃/dry and wet）. Strength performance of stitched composite laminates is also studied using finite element analysis （FEA） model and compared with the experimental results to validate the model. It is found that under similar environmental conditions, the open-hole compressive strength of stitched laminate is decreased and open-hole tensile strength increased as compared to the unstitched laminates. Predicted tensile and compressive strengths are found to be in a good agreement with the test results and the relative error in all cases is less than 15%.
文摘Newcastle disease (ND) virus is a leading threat to commercial and domestic poultry in Pakistan. The virus infects and constitutes irreversible impairment to the nervous system, damages the respiratory system, and marks severe gastrointestinal lesions leading to heavy mortality in short-living birds and substantial losses in layers and breeders. The continuous emergence and evolution of the virus made it inclined to evade the humoral response and indirectly the circumvention of artificial active immunization. Newcastle disease is caused by the orthoavula genus of the paramyxoviridae family and has shown high genetic diversity even in their genotypes while information regarding enzootic trends of the virus is scanty in Pakistan. A total of 40 tracheal samples of NDV were collected from different commercial broiler farms and 11 isolates of NDV were identified. In the current study, we determined the genetic diversity of the Newcastle disease virus based on the partial sequencing of the fusion protein gene available in the NCBI database. Genetic analysis showed that seven isolates belonged to class I genotype VII and four belonged to class II genotype II. Interestingly, two isolates had epidemiological connections with vaccine-like class II genotype II. Our findings, concerning the recent outbreaks of class I genotype VII and class II genotype II of NDV in vaccinated commercial flocks, suggest possible potential partial mutations in the fusion protein gene. Genetic diversity and formation of the new cleavage site in an important neutralizing protein of wild strain are linked with the potency of artificial active immunization and a major cause of vaccine failure.
文摘Background: Cut-throat injury is a potentially fatal condition that may be associated with serious morbidity and mortality. The neck region is particularly at risk of serious injuries due to the location of vital structures, including nerves, viscera, and major vessels. Although cut-throat injury is said to be rare in children, its occurrence has been reported in some series. Management of this condition requires a multidisciplinary approach for a better outcome. Aim: The aim of this report is to highlight the successful management of an alarming case of severe cut-throat injury with associated laryngeal injury in a child. Case presentation: A 12-year-old boy presented with a cut-throat following an assault by an unknown person. Examination revealed an acutely ill child, conscious but pale. He sustained a deep transverse laceration that transected the thyroid cartilage, exposing the laryngeal cavity. An assessment of Zone II penetrating neck injury was made. He was resuscitated, and had emergency neck exploration, tracheostomy, and repair of the injuries. The patient was followed up for 6 months, and had a good voice outcome, with no significant complication. Conclusion: Cut-throat injury is rare in children. But it is a potentially life-threatening condition. It is therefore important to recognize this entity and develop effective protocol of management in our environment.
文摘Hyperparameter tuning is a key step in developing high-performing machine learning models, but searching large hyperparameter spaces requires extensive computation using standard sequential methods. This work analyzes the performance gains from parallel versus sequential hyperparameter optimization. Using scikit-learn’s Randomized SearchCV, this project tuned a Random Forest classifier for fake news detection via randomized grid search. Setting n_jobs to -1 enabled full parallelization across CPU cores. Results show the parallel implementation achieved over 5× faster CPU times and 3× faster total run times compared to sequential tuning. However, test accuracy slightly dropped from 99.26% sequentially to 99.15% with parallelism, indicating a trade-off between evaluation efficiency and model performance. Still, the significant computational gains allow more extensive hyperparameter exploration within reasonable timeframes, outweighing the small accuracy decrease. Further analysis could better quantify this trade-off across different models, tuning techniques, tasks, and hardware.
基金Supported by the Natural Sciences Foundation of China(11975145)Faisal Javed acknowledges(YS304023917)the Support to his Postdoctoral Fellowship at Zhejiang Normal University,ChinaG.Mustafa acknowledges Grant No.ZC304022919 to Support his Postdoctoral Fellowship at Zhejiang Normal University,China。
文摘This study examines a recently hypothesized black hole,which is a perfect solution of metric-affine gravity with a positive cosmological constant,and its thermodynamic features as well as the Joule-Thomson expansion.We develop some thermodynamical quantities,such as volume,Gibbs free energy,and heat capacity,using the entropy and Hawking temperature.We also examine the first law of thermodynamics and thermal fluctuations,which might eliminate certain black hole instabilities.In this regard,a phase transition from unstable to stable is conceivable when the first law order corrections are present.In addition,we study the efficiency of this system as a heat engine and the effect of metric-affine gravity for the physical parameters q_(e),q_(m),κ_(s),κ_(d),and κ_(sh).Further,we study the Joule-Thomson coefficient and inversion temperature,and observe the isenthalpic curves in the Ti−Pi plane.In metric-affine gravity,a comparison is made between a van der Waals fluid and a black hole to study their similarities and differences.
