With the miniaturization and high-frequency evolution of antennas in 5G/6G communications,aerospace,and transportation,polymer composite papers integrating superior wave-transparent performance and thermal conductivit...With the miniaturization and high-frequency evolution of antennas in 5G/6G communications,aerospace,and transportation,polymer composite papers integrating superior wave-transparent performance and thermal conductivity for radar antenna systems are urgently needed.Herein,a down-top strategy was employed to synthesize poly(p-phenylene benzobisoxazole)precursor nanofibers(prePNF).The prePNF was then uniformly mixed with fluorinated graphene(FG)to fabricate FG/PNF composite papers through consecutively suction filtration,hot-pressing,and thermal annealing.The hydroxyl and amino groups in prePNF enhanced the stability of FG/prePNF dispersion,while the increasedπ-πinteractions between PNF and FG after annealing improved their compatibility.The preparation time and cost of PNF paper was significantly reduced when applying this strategy,which enabled its large-scale production.Furthermore,the prepared FG/PNF composite papers exhibited excellent wave-transparent performance and thermal conductivity.When the mass fraction of FG was 40 wt%,the FG/PNF composite paper prepared via the down-top strategy achieved the wave-transparent coefficient(|T|2)of 96.3%under 10 GHz,in-plane thermal conductivity(λ_(∥))of 7.13 W m^(−1)K^(−1),and through-plane thermal conductivity(λ_(⊥))of 0.67 W m^(−1)K^(−1),outperforming FG/PNF composite paper prepared by the top-down strategy(|T|2=95.9%,λ_(∥)=5.52 W m^(−1)K^(−1),λ_(⊥)=0.52 W m^(−1)K^(−1))and pure PNF paper(|T|2=94.7%,λ_(∥)=3.04 W m^(−1)K^(−1),λ_(⊥)=0.24 W m^(−1)K^(−1)).Meanwhile,FG/PNF composite paper(with 40 wt%FG)through the down-top strategy also demonstrated outstanding mechanical properties with tensile strength and toughness reaching 197.4 MPa and 11.6 MJ m^(−3),respectively.展开更多
In the peripheral nervous system,the activation of Sirtuin 1 can improve insulin resistance;however,the role played by Sirtuin 1 in the central nervous system remains unknown.In this study,rat models of diabetes melli...In the peripheral nervous system,the activation of Sirtuin 1 can improve insulin resistance;however,the role played by Sirtuin 1 in the central nervous system remains unknown.In this study,rat models of diabetes mellitus were generated by a single injection of streptozotocin.At 8 weeks after streptozotocin injection,the Morris water maze test and western blot assays confirmed that the diabetic model rats had learning and memory deficits,insulin resistance,and Sirtuin 1 expression could be detected in the hippocampus.Insulin and the insulin receptor inhibitor S961 were intranasally administered to investigate the regulatory effects of insulin signaling on Sirtuin 1.The results showed that insulin administration improved the impaired cognitive function of diabetic model rats and increased the expression levels of phosphorylated insulin receptor,phosphorylated insulin receptor substrate 1,and Sirtuin 1 in the hippocampus.Conversely,S961 administration resulted in more severe cognitive dysfunction and reduced the expression levels of phosphorylated insulin receptor,phosphorylated insulin receptor substrate 1,and Sirtuin 1.The Sirtuin 1 activator SRT2104 and the inhibitor Sirtinol were injected into the lateral ventricle,which revealed that the activation of Sirtuin 1 increased the expression levels of target of rapamycin complex 1,phosphorylated cAMP-response elementbinding protein,and brain-derived neurotrophic factor.Hippocampal dendritic length and spine density also increased in response to Sirtuin 1 activation.In contrast,Sirtinol decreased the expression levels of target of rapamycin complex 1,phosphorylated cAMP-response elementbinding protein,and brain-derived neurotrophic factor and damaged the dendritic structure.These findings suggest that the Sirtuin 1 signaling pathway plays an important role in the development of insulin resistance-related cognitive deficits in diabetic rats.This study was approved by the Animal Ethics Welfare Committee of the First Affiliated Hospital of Hunan University of Chinese Medicine(approval No.ZYFY201811207)in November 2018.展开更多
A jet mill bit(JMB)is proposed to increase the drilling efficiency and safety of horizontal wells,which has the hydraulic characteristics of depressurization and cuttings cleaning.This paper fills the gap in the hydra...A jet mill bit(JMB)is proposed to increase the drilling efficiency and safety of horizontal wells,which has the hydraulic characteristics of depressurization and cuttings cleaning.This paper fills the gap in the hydraulic study of the JMB by focusing on the hydraulic modeling and optimization of the JMB and considering these two hydraulic characteristics.First,the hydraulic depressurization model and the hydraulic cuttings cleaning model of the JMB are developed respectively.In the models,the pressure ratio and efficiency are chosen as the evaluation parameters of the depressurization capacity of the JMB,and the jet hydraulic power and jet impact force are chosen as the evaluation parameters of cuttings cleaning capacity of the JMB.Second,based on the hydraulic models,the effects of model parameters[friction loss coefficient,target inclination angle,rate of penetration(ROP),flow ratio,and well depth]on the hydraulic performance of the JMB are investigated.The results show that an increase in the friction loss coefficient and target inclination angle cause a significant reduction in the hydraulic depressurization capacity,and the effect of ROP is negligible.The flow ratio is positively related to the hydraulic cuttings cleaning capacity,and the well depth determines the maximum hydraulic cuttings cleaning capacity.Finally,by combining the hydraulic depressurization model and hydraulic cuttings cleaning model,an optimization method of JMB hydraulics is proposed to simultaneously maximize the jet depressurization capacity and the cuttings cleaning capacity.According to the drilling parameters given,the optimal values of the drilling fluid flow rate,backward nozzle diameter,forward nozzle diameter,and throat diameter can be determined.Moreover,a case study is conducted to verify the effectiveness of the optimization method.展开更多
Objective:To explore the application of the theory of"Tongqixiangqiu"and its application in traditional Chinese medicine in order to find out the clinical application of colorectal cancer.Methods:Referring t...Objective:To explore the application of the theory of"Tongqixiangqiu"and its application in traditional Chinese medicine in order to find out the clinical application of colorectal cancer.Methods:Referring to the ancient medical works and modern literature on the theory of"Tongqixiangqiu",combined with the disease characteristics of colorectal cancer and the clinical experience of famous doctors in ancient and modern times,to explore its application in the clinical treatment of colorectal cancer.Results:The theory of"Tongqixiangqiu"has rich connotations,among which"anti-adjuvant therapy"and"lung and intestine combined treatment"are the representatives of the specific application of the theory.The methods of cold and heat counteraction,compatibility and external treatment as well as the idea of spleen deficiency and Qi stagnation type colorectal cancer pay attention to tonifying Fei qi,nourishing Fei yin,and promoting Sanjiao Qi mechanism play an important role in the differentiation and treatment of colorectal cancer in TCM.Conclusion:The theory of"Tongqixiangqiu"is widely used in the treatment of colorectal cancer,which has the advantages of significant curative effect,synergism and toxicity reduction,prolonging the survival period and improving the quality of life of patients.展开更多
Objective:To compare the efficacy of anal adenectomy with virtual hanging wire and anal fistulotomy in the treatment of low anal fistula in infants and children.Methods:60 children with low anal fistula who were admit...Objective:To compare the efficacy of anal adenectomy with virtual hanging wire and anal fistulotomy in the treatment of low anal fistula in infants and children.Methods:60 children with low anal fistula who were admitted to our hospital from October 2021 to March 2022 and met the inclusion criteria were randomly divided into two groups of 30 cases each;the treatment group was treated with anal adenectomy and virtual hanging wire surgery,and the control group was treated with anal fistula resection.The clinical efficacy after treatment was compared.Results:The total effective rate of both groups was 96.67%and the difference between the two groups was not statistically significant(P>0.05).The postoperative pain score of the treatment group was lower than that of the control group(P<0.05).The length of hospitalization and healing time of the treatment group was lower than that of the control group(P<0.05).The anal function of the patients in both groups was normal,and there was no adverse reaction.Conclusion:Anal gland excision and virtual hanging surgery for the treatment of low anal fistula in infants and children have the advantages of mild pain,reduced length of hospitalization,short healing time,and better patient experience as compared to anal fistula excision.展开更多
Controlling heavy metal pollution in agricultural soil has been a significant challenge.These heavy metals seriously threaten the surrounding ecological environment and human health.The effective assessment and remedi...Controlling heavy metal pollution in agricultural soil has been a significant challenge.These heavy metals seriously threaten the surrounding ecological environment and human health.The effective assessment and remediation of heavy metals in agricultural soils are crucial.These two aspects support each other,forming a close and complete decisionmaking chain.Therefore,this review systematically summarizes the distribution characteristics of soil heavy metal pollution,the correlation between soil and crop heavy metal contents,the presence pattern and migration and transformation mode of heavy metals in the soil-crop system.The advantages and disadvantages of the risk evaluation tools and models of heavy metal pollution in farmland are further outlined,which provides important guidance for an in-depth understanding of the characteristics of heavymetal pollution in farmland soils and the assessment of the environmental risk.Soil remediation strategies involve multiple physical,chemical,biological and even combined technologies,and this paper compares the potential and effect of the above current remediation technologies in heavy metal polluted farmland soils.Finally,the main problems and possible research directions of future heavy metal risk assessment and remediation technologies in agricultural soils are prospected.This review provides new ideas for effective assessment and selection of remediation technologies based on the characterization of soil heavy metals.展开更多
Poly(p-phenylenebenzobisoxazole)nanofibers(PNF),as a novel kind of nanofibers,have attracted significant attention from researchers.However,their poor ultraviolet(UV)resistance limits their potential applications.In t...Poly(p-phenylenebenzobisoxazole)nanofibers(PNF),as a novel kind of nanofibers,have attracted significant attention from researchers.However,their poor ultraviolet(UV)resistance limits their potential applications.In this work,zinc oxide(ZnO)was uniformly coated on the surface of PNF-containing polysilsesquioxane(POSS)via in-situ growth to obtain(POSS-PNF)@ZnO.Subsequently,(POSS-PNF)@ZnO wave-transparent composite paper was then fabricated using a“vacuum filtration-assisted hot-pressing”method.Based on the coordination interaction between O–Cdouble bondO groups of PNFs and ZnO,as well as the UV absorption/shielding capability of ZnO,the(POSS-PNF)@ZnO wave-transparent composite paper exhibited superior mechanical properties and UV resistance.At a hydrothermal reaction temperature of 80℃,the prepared(POSS-PNF)@ZnO wave-transparent composite paper exhibited the highest tensile strength(204.5 MPa)and toughness(12.3 MJ m^(−3)),which represents increases of 23.7%and 32.3%,respectively,compared to POSS-PNF wave-transparent paper.After 288 h of UV aging,the tensile strength retention rate was 77.4%,significantly higher than the 53.7%of POSS-PNF wave-transparent composite paper.Moreover,it exhibited excellent wave-transparent performance with a dielectric constant(ε)of 2.15 and a dielectric loss tangent(tanδ)of 0.044 at 10 GHz,resulting in a wave-transparent coefficient of 95.9%.展开更多
BACKGROUND Sharp foreign body ingestion can cause gastrointestinal tract mucosa injury and requires proper endoscopic removal.Typically,protective devices are used to reduce mucosal damage.This case presents an altern...BACKGROUND Sharp foreign body ingestion can cause gastrointestinal tract mucosa injury and requires proper endoscopic removal.Typically,protective devices are used to reduce mucosal damage.This case presents an alternative approach for the endoscopic removal of a large,irregular,and sharp foreign body(chicken bone)when traditional protective devices are inadequate,thus contributing to the management of such ingestions.CASE SUMMARY A 57-year-old male presented with a history of swallowing an irregular and sharp-pointed chicken bone.Emergent endoscopy showed it was tightly embedded in the esophageal wall,with minor bleeding.The chicken bone was grasped and moved cautiously using a foreign forceps.It was loosened after repeated attempts but could not pass through the pharynx.Considering possible mucosal damage,it was carefully pushed into the stomach cavity and then wrapped in a condom.The chicken bone was retrieved uneventfully by grasping the open edge of the condom with foreign forceps.No additional damage was found,except for primary esophageal injuries caused by the embedded chicken bone.The patient was discharged on the following day.Our experience demonstrated that condoms can be an alternative as a protective device under such conditions.CONCLUSION Condoms can serve as an alternative when traditional protective devices are unsuitable.Because of its smooth and oily nature,it can provide mucosal protection and lubrication during endoscopic removal.展开更多
Aiming to provide optimal solutions to the sluggish kinetics of Mg(BH_(4))_(2),this study proposes,for the first time,a novel machine learning model to predict dehydrogenation behaviors of modified Mg(BH_(4))_(2).Nota...Aiming to provide optimal solutions to the sluggish kinetics of Mg(BH_(4))_(2),this study proposes,for the first time,a novel machine learning model to predict dehydrogenation behaviors of modified Mg(BH_(4))_(2).Notably,numerous data points are collected from temperatureprogrammed,isothermal,and cyclic dehydrogenation behaviors,a neural network model is proposed by using multi-head attention mechanisms,which exhibits the highest predictive performance compared to traditional machine learning models.The study also ranks different variables influencing dehydrogenation processes,employing interpretable analysis to identify critical variable thresholds,offering guidance for the experimental parameter design.The model can also be adapted to scenarios involving co-doping of hydrides and catalysts in Mg(BH_(4))_(2) system and proved high accuracy and scalability in predicting dehydrogenation curves under diverse conditions.Employing the model,performance predictions for a series of undeveloped Mg(BH_(4))_(2) co-doping systems can be made,and superior dehydrogenation catalytic effects of fluorinated graphite(FGi)are uncovered.Real-world experimental validation of the optimal Mg(BH_(4))_(2)-LiBH_(4)-FGi system confirms consistency with model predictions,and performance enhancement attributes to experimental parameter optimization.Further characterizations provide mechanistic insights into the synergistic interactions of FGi and LiBH_(4).This work paves the way for advancing utilization of machine learning in the high-capacity hydrogen storage field.展开更多
Intelligent sorting is an important prerequisite for the full quantitative consumption and harmless disposal of kitchen waste.The existing object detection method based on an ImageNet pre-trained model is an effective...Intelligent sorting is an important prerequisite for the full quantitative consumption and harmless disposal of kitchen waste.The existing object detection method based on an ImageNet pre-trained model is an effective way of sorting.Owing to significant domain gaps between natural images and kitchen waste images,it is difficult to reflect the characteristics of diverse scales and dense distribution in kitchen waste based on an ImageNet pre-trained model,leading to poor generalisation.In this article,the authors propose the first pre-trained model for kitchen waste sorting called KitWaSor,which combines both contrastive learning(CL)and masked image modelling(MIM)through self-supervised learning(SSL).First,to address the issue of diverse scales,the authors propose a mixed masking strategy by introducing an incomplete masking branch based on the original random masking branch.It prevents the complete loss of small-scale objects while avoiding excessive leakage of large-scale object pixels.Second,to address the issue of dense distribution,the authors introduce semantic consistency constraints on the basis of the mixed masking strategy.That is,object semantic reasoning is performed through semantic consistency constraints to compensate for the lack of contextual information.To train KitWaSor,the authors construct the first million-level kitchen waste dataset across seasonal and regional distributions,named KWD-Million.Extensive experiments show that KitWaSor achieves state-of-the-art(SOTA)performance on the two most relevant downstream tasks for kitchen waste sorting(i.e.image classification and object detection),demonstrating the effectiveness of the proposed KitWaSor.展开更多
Objective The objective of our study was to evaluate the vaccine effectiveness(VE)of the pentavalent rotavirus vaccine(RV5)among<5-year-old children in three provinces of China during 2020-2024 via a propensity sco...Objective The objective of our study was to evaluate the vaccine effectiveness(VE)of the pentavalent rotavirus vaccine(RV5)among<5-year-old children in three provinces of China during 2020-2024 via a propensity score-matched test-negative case-control study.Methods Electronic health records and immunization information systems were used to obtain data on acute gastroenteritis(AGE)cases tested for rotavirus(RV)infection.RV-positive cases were propensity score matched with RV-negative controls for age,visit month,and province.Results The study included 27,472 children with AGE aged 8 weeks to 4 years at the time of AGE diagnosis;7.98%(2,192)were RV-positive.The VE(95%confidence interval,CI)of 1-2 and 3 doses of RV5 against any medically attended RV infection(inpatient or outpatient)was 57.6%(39.8%,70.2%)and 67.2%(60.3%,72.9%),respectively.Among children who received the 3rd dose before turning 5 months of age,3-dose VE decreased from 70.4%(53.9%,81.1%)(<5 months since the 3rd dose)to 63.0%(49.1%,73.0%)(≥1 year since the 3rd dose).The three-dose VE rate was 69.4%(41.3%,84.0%)for RVGE hospitalization and 57.5%(38.9%,70.5%)for outpatient-only medically attended RVGE.Conclusion Three-dose RV5 VE against rotavirus gastroenteritis(RVGE)in children aged<5 years was higher than 1-2-dose VE.Three-dose VE decreased with time since the 3rd dose in children who received the 3rd dose before turning five months of age,but remained above 60%for at least one year.VE was higher for RVGE hospitalizations than for medically attended outpatient visits.展开更多
MnO_(2)-doped Ca_(0.97)Bi_(2.03)Nb_(2)O_(9) ceramics with greatly improved piezoelectric performance were prepared via conventional solid state sintering method.The effects of MnO_(2) doping on the microstructure and ...MnO_(2)-doped Ca_(0.97)Bi_(2.03)Nb_(2)O_(9) ceramics with greatly improved piezoelectric performance were prepared via conventional solid state sintering method.The effects of MnO_(2) doping on the microstructure and electrical properties of Ca_(0.97)Bi_(2.03)Nb_(2)O_(9) ceramics were studied.X-ray diffraction(XRD)analysis and Rietveld refinement revealed a reduction in orthorhombicity with MnO_(2) doping,which contributed to the enhancement of the piezoelectric properties.Furthermore,the introduction of MnO_(2) lowered the sintering temperature,thereby reducing the formation of oxygen vacancies in the ceramic.The optimal performance was achieved in the Ca_(0.97)Bi_(2.03)Nb_(2)O_(9)−0.3wt.%MnO_(2) sample,exhibiting a piezoelectric coefficient(d33)of 13.6 pC/N,a DC resistivity of 3×10^(6)Ω·cm at 500℃,and a Curie temperature of 965℃.Additionally,all doped samples demonstrated excellent thermal stability over a wide temperature range,from room temperature to 900℃.展开更多
The objective of present study was to investigate the antioxidative and cardioprotective effects of polyphenol extracts from sea buckthorn (PESB) against myocardial ischemia reperfusion injury (MIRI). PESB was analyze...The objective of present study was to investigate the antioxidative and cardioprotective effects of polyphenol extracts from sea buckthorn (PESB) against myocardial ischemia reperfusion injury (MIRI). PESB was analyzed using HPLC-DAD and their antioxidant activities were evaluated by measuring the intrinsic free radicals cavenging capacity and inhibiting the formation of hydroxyl radical capacity. Experiments on the isolated rat hearts were carried out according to the improved Langendorff retrograde perfusion technology. Coronary effluent of lactate dehydrogenase (LDH) and creatine kinase isoenzyme (CK-MB) activities were analyzed to determine the extent of myocardial injury. Protein expression levels of Beclin-1, microtubule-associated protein 1 light chain 3 (LC3) I and II were measured to evaluate the degree of autophagy. In conclusion, coupled results from both in vivo and in vitro experiments have confirmed that PESB has potential health implications in both prevention and amelioration of MIRI, which may be attributed to the inhibition of autophagy.展开更多
基金the support from the National Natural Science Foundation of China(52473083,52373089,52403085)Natural Science Basic Research Program of Shaanxi(2024JC-TBZC-04)+2 种基金the Innovation Capability Support Program of Shaanxi(2024RS-CXTD-57)Natural Science Basic Research Plan in Shaanxi Province of China(2024JC-YBMS-279)Natural Science Foundation of Chongqing,China(2023NSCQMSX2547)
文摘With the miniaturization and high-frequency evolution of antennas in 5G/6G communications,aerospace,and transportation,polymer composite papers integrating superior wave-transparent performance and thermal conductivity for radar antenna systems are urgently needed.Herein,a down-top strategy was employed to synthesize poly(p-phenylene benzobisoxazole)precursor nanofibers(prePNF).The prePNF was then uniformly mixed with fluorinated graphene(FG)to fabricate FG/PNF composite papers through consecutively suction filtration,hot-pressing,and thermal annealing.The hydroxyl and amino groups in prePNF enhanced the stability of FG/prePNF dispersion,while the increasedπ-πinteractions between PNF and FG after annealing improved their compatibility.The preparation time and cost of PNF paper was significantly reduced when applying this strategy,which enabled its large-scale production.Furthermore,the prepared FG/PNF composite papers exhibited excellent wave-transparent performance and thermal conductivity.When the mass fraction of FG was 40 wt%,the FG/PNF composite paper prepared via the down-top strategy achieved the wave-transparent coefficient(|T|2)of 96.3%under 10 GHz,in-plane thermal conductivity(λ_(∥))of 7.13 W m^(−1)K^(−1),and through-plane thermal conductivity(λ_(⊥))of 0.67 W m^(−1)K^(−1),outperforming FG/PNF composite paper prepared by the top-down strategy(|T|2=95.9%,λ_(∥)=5.52 W m^(−1)K^(−1),λ_(⊥)=0.52 W m^(−1)K^(−1))and pure PNF paper(|T|2=94.7%,λ_(∥)=3.04 W m^(−1)K^(−1),λ_(⊥)=0.24 W m^(−1)K^(−1)).Meanwhile,FG/PNF composite paper(with 40 wt%FG)through the down-top strategy also demonstrated outstanding mechanical properties with tensile strength and toughness reaching 197.4 MPa and 11.6 MJ m^(−3),respectively.
基金This study was supported by the National Natural Science Foundation of China,No.81874464(to YHW)the Natural Science Foundation of Hunan Province of China,No.2019JJ50464(to HY)the Open Fund of the Domestic First-class Discipline Construction Project of Chinese Medicine of Hunan University of Chinese Medicine,No.2018ZYX46(to HY).
文摘In the peripheral nervous system,the activation of Sirtuin 1 can improve insulin resistance;however,the role played by Sirtuin 1 in the central nervous system remains unknown.In this study,rat models of diabetes mellitus were generated by a single injection of streptozotocin.At 8 weeks after streptozotocin injection,the Morris water maze test and western blot assays confirmed that the diabetic model rats had learning and memory deficits,insulin resistance,and Sirtuin 1 expression could be detected in the hippocampus.Insulin and the insulin receptor inhibitor S961 were intranasally administered to investigate the regulatory effects of insulin signaling on Sirtuin 1.The results showed that insulin administration improved the impaired cognitive function of diabetic model rats and increased the expression levels of phosphorylated insulin receptor,phosphorylated insulin receptor substrate 1,and Sirtuin 1 in the hippocampus.Conversely,S961 administration resulted in more severe cognitive dysfunction and reduced the expression levels of phosphorylated insulin receptor,phosphorylated insulin receptor substrate 1,and Sirtuin 1.The Sirtuin 1 activator SRT2104 and the inhibitor Sirtinol were injected into the lateral ventricle,which revealed that the activation of Sirtuin 1 increased the expression levels of target of rapamycin complex 1,phosphorylated cAMP-response elementbinding protein,and brain-derived neurotrophic factor.Hippocampal dendritic length and spine density also increased in response to Sirtuin 1 activation.In contrast,Sirtinol decreased the expression levels of target of rapamycin complex 1,phosphorylated cAMP-response elementbinding protein,and brain-derived neurotrophic factor and damaged the dendritic structure.These findings suggest that the Sirtuin 1 signaling pathway plays an important role in the development of insulin resistance-related cognitive deficits in diabetic rats.This study was approved by the Animal Ethics Welfare Committee of the First Affiliated Hospital of Hunan University of Chinese Medicine(approval No.ZYFY201811207)in November 2018.
基金financially supported by Youth Project of Natural Science Basic Research Program of Shaanxi Province(Grant number:2023-JC-QN-0538)Scientifical Research Program for Youth Innovation Team Construction of Shaanxi Provincial Department of Education(Grant number:21JP054,22JP032)+1 种基金National Natural Science Foundation of China(Grant numbers:52174012,51804322,51821092,51774301,U1762214)Open Fund(PLC 20210404)of State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation(Chengdu University of Technology)。
文摘A jet mill bit(JMB)is proposed to increase the drilling efficiency and safety of horizontal wells,which has the hydraulic characteristics of depressurization and cuttings cleaning.This paper fills the gap in the hydraulic study of the JMB by focusing on the hydraulic modeling and optimization of the JMB and considering these two hydraulic characteristics.First,the hydraulic depressurization model and the hydraulic cuttings cleaning model of the JMB are developed respectively.In the models,the pressure ratio and efficiency are chosen as the evaluation parameters of the depressurization capacity of the JMB,and the jet hydraulic power and jet impact force are chosen as the evaluation parameters of cuttings cleaning capacity of the JMB.Second,based on the hydraulic models,the effects of model parameters[friction loss coefficient,target inclination angle,rate of penetration(ROP),flow ratio,and well depth]on the hydraulic performance of the JMB are investigated.The results show that an increase in the friction loss coefficient and target inclination angle cause a significant reduction in the hydraulic depressurization capacity,and the effect of ROP is negligible.The flow ratio is positively related to the hydraulic cuttings cleaning capacity,and the well depth determines the maximum hydraulic cuttings cleaning capacity.Finally,by combining the hydraulic depressurization model and hydraulic cuttings cleaning model,an optimization method of JMB hydraulics is proposed to simultaneously maximize the jet depressurization capacity and the cuttings cleaning capacity.According to the drilling parameters given,the optimal values of the drilling fluid flow rate,backward nozzle diameter,forward nozzle diameter,and throat diameter can be determined.Moreover,a case study is conducted to verify the effectiveness of the optimization method.
基金Project of National Clinical Research Base of Traditional Chinese Medicine in Jiangsu Province,China(No.JD2019SZXZD06)。
文摘Objective:To explore the application of the theory of"Tongqixiangqiu"and its application in traditional Chinese medicine in order to find out the clinical application of colorectal cancer.Methods:Referring to the ancient medical works and modern literature on the theory of"Tongqixiangqiu",combined with the disease characteristics of colorectal cancer and the clinical experience of famous doctors in ancient and modern times,to explore its application in the clinical treatment of colorectal cancer.Results:The theory of"Tongqixiangqiu"has rich connotations,among which"anti-adjuvant therapy"and"lung and intestine combined treatment"are the representatives of the specific application of the theory.The methods of cold and heat counteraction,compatibility and external treatment as well as the idea of spleen deficiency and Qi stagnation type colorectal cancer pay attention to tonifying Fei qi,nourishing Fei yin,and promoting Sanjiao Qi mechanism play an important role in the differentiation and treatment of colorectal cancer in TCM.Conclusion:The theory of"Tongqixiangqiu"is widely used in the treatment of colorectal cancer,which has the advantages of significant curative effect,synergism and toxicity reduction,prolonging the survival period and improving the quality of life of patients.
基金Xi’an Municipal Bureau of Science and Technology,No.21YXYJ0060。
文摘Objective:To compare the efficacy of anal adenectomy with virtual hanging wire and anal fistulotomy in the treatment of low anal fistula in infants and children.Methods:60 children with low anal fistula who were admitted to our hospital from October 2021 to March 2022 and met the inclusion criteria were randomly divided into two groups of 30 cases each;the treatment group was treated with anal adenectomy and virtual hanging wire surgery,and the control group was treated with anal fistula resection.The clinical efficacy after treatment was compared.Results:The total effective rate of both groups was 96.67%and the difference between the two groups was not statistically significant(P>0.05).The postoperative pain score of the treatment group was lower than that of the control group(P<0.05).The length of hospitalization and healing time of the treatment group was lower than that of the control group(P<0.05).The anal function of the patients in both groups was normal,and there was no adverse reaction.Conclusion:Anal gland excision and virtual hanging surgery for the treatment of low anal fistula in infants and children have the advantages of mild pain,reduced length of hospitalization,short healing time,and better patient experience as compared to anal fistula excision.
基金supported by the National Natural Science Foundation of China(Nos.52100184,and U22A20617).
文摘Controlling heavy metal pollution in agricultural soil has been a significant challenge.These heavy metals seriously threaten the surrounding ecological environment and human health.The effective assessment and remediation of heavy metals in agricultural soils are crucial.These two aspects support each other,forming a close and complete decisionmaking chain.Therefore,this review systematically summarizes the distribution characteristics of soil heavy metal pollution,the correlation between soil and crop heavy metal contents,the presence pattern and migration and transformation mode of heavy metals in the soil-crop system.The advantages and disadvantages of the risk evaluation tools and models of heavy metal pollution in farmland are further outlined,which provides important guidance for an in-depth understanding of the characteristics of heavymetal pollution in farmland soils and the assessment of the environmental risk.Soil remediation strategies involve multiple physical,chemical,biological and even combined technologies,and this paper compares the potential and effect of the above current remediation technologies in heavy metal polluted farmland soils.Finally,the main problems and possible research directions of future heavy metal risk assessment and remediation technologies in agricultural soils are prospected.This review provides new ideas for effective assessment and selection of remediation technologies based on the characterization of soil heavy metals.
基金funding from the Foundation of the National Natural Science Foundation of China(Nos.52373089 and 52403085)the Startup Foundation of Chongqing Normal University(No.23XLB011)+1 种基金the Science and Technology Research Program of Chongqing Municipal Education Commission(No.KJQN202300561)Undergraduate Innovation&Business Program in Northwestern Polytechnical University(No.S202410699657)。
文摘Poly(p-phenylenebenzobisoxazole)nanofibers(PNF),as a novel kind of nanofibers,have attracted significant attention from researchers.However,their poor ultraviolet(UV)resistance limits their potential applications.In this work,zinc oxide(ZnO)was uniformly coated on the surface of PNF-containing polysilsesquioxane(POSS)via in-situ growth to obtain(POSS-PNF)@ZnO.Subsequently,(POSS-PNF)@ZnO wave-transparent composite paper was then fabricated using a“vacuum filtration-assisted hot-pressing”method.Based on the coordination interaction between O–Cdouble bondO groups of PNFs and ZnO,as well as the UV absorption/shielding capability of ZnO,the(POSS-PNF)@ZnO wave-transparent composite paper exhibited superior mechanical properties and UV resistance.At a hydrothermal reaction temperature of 80℃,the prepared(POSS-PNF)@ZnO wave-transparent composite paper exhibited the highest tensile strength(204.5 MPa)and toughness(12.3 MJ m^(−3)),which represents increases of 23.7%and 32.3%,respectively,compared to POSS-PNF wave-transparent paper.After 288 h of UV aging,the tensile strength retention rate was 77.4%,significantly higher than the 53.7%of POSS-PNF wave-transparent composite paper.Moreover,it exhibited excellent wave-transparent performance with a dielectric constant(ε)of 2.15 and a dielectric loss tangent(tanδ)of 0.044 at 10 GHz,resulting in a wave-transparent coefficient of 95.9%.
文摘BACKGROUND Sharp foreign body ingestion can cause gastrointestinal tract mucosa injury and requires proper endoscopic removal.Typically,protective devices are used to reduce mucosal damage.This case presents an alternative approach for the endoscopic removal of a large,irregular,and sharp foreign body(chicken bone)when traditional protective devices are inadequate,thus contributing to the management of such ingestions.CASE SUMMARY A 57-year-old male presented with a history of swallowing an irregular and sharp-pointed chicken bone.Emergent endoscopy showed it was tightly embedded in the esophageal wall,with minor bleeding.The chicken bone was grasped and moved cautiously using a foreign forceps.It was loosened after repeated attempts but could not pass through the pharynx.Considering possible mucosal damage,it was carefully pushed into the stomach cavity and then wrapped in a condom.The chicken bone was retrieved uneventfully by grasping the open edge of the condom with foreign forceps.No additional damage was found,except for primary esophageal injuries caused by the embedded chicken bone.The patient was discharged on the following day.Our experience demonstrated that condoms can be an alternative as a protective device under such conditions.CONCLUSION Condoms can serve as an alternative when traditional protective devices are unsuitable.Because of its smooth and oily nature,it can provide mucosal protection and lubrication during endoscopic removal.
基金the National Natural Science Foundation of China(No.52171223 and U20A20237).
文摘Aiming to provide optimal solutions to the sluggish kinetics of Mg(BH_(4))_(2),this study proposes,for the first time,a novel machine learning model to predict dehydrogenation behaviors of modified Mg(BH_(4))_(2).Notably,numerous data points are collected from temperatureprogrammed,isothermal,and cyclic dehydrogenation behaviors,a neural network model is proposed by using multi-head attention mechanisms,which exhibits the highest predictive performance compared to traditional machine learning models.The study also ranks different variables influencing dehydrogenation processes,employing interpretable analysis to identify critical variable thresholds,offering guidance for the experimental parameter design.The model can also be adapted to scenarios involving co-doping of hydrides and catalysts in Mg(BH_(4))_(2) system and proved high accuracy and scalability in predicting dehydrogenation curves under diverse conditions.Employing the model,performance predictions for a series of undeveloped Mg(BH_(4))_(2) co-doping systems can be made,and superior dehydrogenation catalytic effects of fluorinated graphite(FGi)are uncovered.Real-world experimental validation of the optimal Mg(BH_(4))_(2)-LiBH_(4)-FGi system confirms consistency with model predictions,and performance enhancement attributes to experimental parameter optimization.Further characterizations provide mechanistic insights into the synergistic interactions of FGi and LiBH_(4).This work paves the way for advancing utilization of machine learning in the high-capacity hydrogen storage field.
基金National Key Research and Development Program of China,Grant/Award Number:2021YFC1910402。
文摘Intelligent sorting is an important prerequisite for the full quantitative consumption and harmless disposal of kitchen waste.The existing object detection method based on an ImageNet pre-trained model is an effective way of sorting.Owing to significant domain gaps between natural images and kitchen waste images,it is difficult to reflect the characteristics of diverse scales and dense distribution in kitchen waste based on an ImageNet pre-trained model,leading to poor generalisation.In this article,the authors propose the first pre-trained model for kitchen waste sorting called KitWaSor,which combines both contrastive learning(CL)and masked image modelling(MIM)through self-supervised learning(SSL).First,to address the issue of diverse scales,the authors propose a mixed masking strategy by introducing an incomplete masking branch based on the original random masking branch.It prevents the complete loss of small-scale objects while avoiding excessive leakage of large-scale object pixels.Second,to address the issue of dense distribution,the authors introduce semantic consistency constraints on the basis of the mixed masking strategy.That is,object semantic reasoning is performed through semantic consistency constraints to compensate for the lack of contextual information.To train KitWaSor,the authors construct the first million-level kitchen waste dataset across seasonal and regional distributions,named KWD-Million.Extensive experiments show that KitWaSor achieves state-of-the-art(SOTA)performance on the two most relevant downstream tasks for kitchen waste sorting(i.e.image classification and object detection),demonstrating the effectiveness of the proposed KitWaSor.
基金the Study on Vaccine Application Evaluation Strategies and Capacity Building (INV-006373)the National Key R&D Program of China(2024YFC2310604)
文摘Objective The objective of our study was to evaluate the vaccine effectiveness(VE)of the pentavalent rotavirus vaccine(RV5)among<5-year-old children in three provinces of China during 2020-2024 via a propensity score-matched test-negative case-control study.Methods Electronic health records and immunization information systems were used to obtain data on acute gastroenteritis(AGE)cases tested for rotavirus(RV)infection.RV-positive cases were propensity score matched with RV-negative controls for age,visit month,and province.Results The study included 27,472 children with AGE aged 8 weeks to 4 years at the time of AGE diagnosis;7.98%(2,192)were RV-positive.The VE(95%confidence interval,CI)of 1-2 and 3 doses of RV5 against any medically attended RV infection(inpatient or outpatient)was 57.6%(39.8%,70.2%)and 67.2%(60.3%,72.9%),respectively.Among children who received the 3rd dose before turning 5 months of age,3-dose VE decreased from 70.4%(53.9%,81.1%)(<5 months since the 3rd dose)to 63.0%(49.1%,73.0%)(≥1 year since the 3rd dose).The three-dose VE rate was 69.4%(41.3%,84.0%)for RVGE hospitalization and 57.5%(38.9%,70.5%)for outpatient-only medically attended RVGE.Conclusion Three-dose RV5 VE against rotavirus gastroenteritis(RVGE)in children aged<5 years was higher than 1-2-dose VE.Three-dose VE decreased with time since the 3rd dose in children who received the 3rd dose before turning five months of age,but remained above 60%for at least one year.VE was higher for RVGE hospitalizations than for medically attended outpatient visits.
基金National Key Research and Development Program of China (No. 2022YFB3807404)State Key Laboratory of Powder Metallurgy, the National Natural Science Foundation of China (No. 52102150, 52302158)Xiaomi Young Talents Program, China。
文摘MnO_(2)-doped Ca_(0.97)Bi_(2.03)Nb_(2)O_(9) ceramics with greatly improved piezoelectric performance were prepared via conventional solid state sintering method.The effects of MnO_(2) doping on the microstructure and electrical properties of Ca_(0.97)Bi_(2.03)Nb_(2)O_(9) ceramics were studied.X-ray diffraction(XRD)analysis and Rietveld refinement revealed a reduction in orthorhombicity with MnO_(2) doping,which contributed to the enhancement of the piezoelectric properties.Furthermore,the introduction of MnO_(2) lowered the sintering temperature,thereby reducing the formation of oxygen vacancies in the ceramic.The optimal performance was achieved in the Ca_(0.97)Bi_(2.03)Nb_(2)O_(9)−0.3wt.%MnO_(2) sample,exhibiting a piezoelectric coefficient(d33)of 13.6 pC/N,a DC resistivity of 3×10^(6)Ω·cm at 500℃,and a Curie temperature of 965℃.Additionally,all doped samples demonstrated excellent thermal stability over a wide temperature range,from room temperature to 900℃.
文摘The objective of present study was to investigate the antioxidative and cardioprotective effects of polyphenol extracts from sea buckthorn (PESB) against myocardial ischemia reperfusion injury (MIRI). PESB was analyzed using HPLC-DAD and their antioxidant activities were evaluated by measuring the intrinsic free radicals cavenging capacity and inhibiting the formation of hydroxyl radical capacity. Experiments on the isolated rat hearts were carried out according to the improved Langendorff retrograde perfusion technology. Coronary effluent of lactate dehydrogenase (LDH) and creatine kinase isoenzyme (CK-MB) activities were analyzed to determine the extent of myocardial injury. Protein expression levels of Beclin-1, microtubule-associated protein 1 light chain 3 (LC3) I and II were measured to evaluate the degree of autophagy. In conclusion, coupled results from both in vivo and in vitro experiments have confirmed that PESB has potential health implications in both prevention and amelioration of MIRI, which may be attributed to the inhibition of autophagy.
