The use of robots to augment human capabilities and assist in work has long been an aspiration.Robotics has been developing since the 1960s when the first industrial robot was introduced.As technology has advanced,rob...The use of robots to augment human capabilities and assist in work has long been an aspiration.Robotics has been developing since the 1960s when the first industrial robot was introduced.As technology has advanced,robotic-assisted surgery has shown numerous advantages,including more precision,efficiency,minimal invasiveness,and safety than is possible with conventional techniques,which are research hotspots and cutting-edge trends.This article reviewed the history of medical robot development and seminal research papers about current research progress.Taking the autonomous dental implant robotic system as an example,the advantages and prospects of medical robotic systems would be discussed which would provide a reference for future research.展开更多
Accurate segmentation of oral surgery-related tissues from cone beam computed tomography(CBCT)images can significantly accelerate treatment planning and improve surgical accuracy.In this paper,we propose a fully autom...Accurate segmentation of oral surgery-related tissues from cone beam computed tomography(CBCT)images can significantly accelerate treatment planning and improve surgical accuracy.In this paper,we propose a fully automated tissue segmentation system for dental implant surgery.Specifically,we propose an image preprocessing method based on data distribution histograms,which can adaptively process CBCT images with different parameters.Based on this,we use the bone segmentation network to obtain the segmentation results of alveolar bone,teeth,and maxillary sinus.We use the tooth and mandibular regions as the ROI regions of tooth segmentation and mandibular nerve tube segmentation to achieve the corresponding tasks.The tooth segmentation results can obtain the order information of the dentition.The corresponding experimental results show that our method can achieve higher segmentation accuracy and efficiency compared to existing methods.Its average Dice scores on the tooth,alveolar bone,maxillary sinus,and mandibular canal segmentation tasks were 96.5%,95.4%,93.6%,and 94.8%,respectively.These results demonstrate that it can accelerate the development of digital dentistry.展开更多
Maximum power point tracking(MPPT)technology plays a key role in improving the energy conversion efficiency of photovoltaic(PV)systems,especially when multiple local maximum power points(LMPPs)occur under partial shad...Maximum power point tracking(MPPT)technology plays a key role in improving the energy conversion efficiency of photovoltaic(PV)systems,especially when multiple local maximum power points(LMPPs)occur under partial shading conditions(PSC).It is necessary to modify the operating point efficiently and accurately with the help of MPPT technology to maximize the collected power.Even though a lot of research has been carried out and impressive progress achieved for MPPT technology,it still faces some challenges and dilemmas.Firstly,the mathematical model established for PV cells is not precise enough.Second,the existing algorithms are often optimized for specific conditions and lack comprehensive adaptability to the actual operating environment.Besides,a single algorithm may not be able to give full play to its advantages.In the end,the selection criteria for choosing the suitable MPPT algorithm/converter combination to achieve better performance in a given scenario is very limited.Therefore,this paper systematically discusses the current research status and challenges faced by PV MPPT technology around the three aspects of MPPT models,algorithms,and hardware implementation.Through in-depth thinking and discussion,it also puts forward positive perspectives on future development,and five forward-looking solutions to improve the performance of PV systems MPPT are suggested.展开更多
目的:通过观察沉默瞬时受体阳离子通道亚家族V成员6(transient receptor potential cation channel,subfamily V member 6,TRPV6)对结肠癌SW480细胞生物学行为的影响和细胞内钙的浓度变化,以及1,25(OH)_2D_3、CaCl_2及CuCl_2在SD大鼠结...目的:通过观察沉默瞬时受体阳离子通道亚家族V成员6(transient receptor potential cation channel,subfamily V member 6,TRPV6)对结肠癌SW480细胞生物学行为的影响和细胞内钙的浓度变化,以及1,25(OH)_2D_3、CaCl_2及CuCl_2在SD大鼠结肠肿瘤模型建立中的影响,探索TRPV6在结肠癌发生过程中的相关作用,为结肠癌的防治寻找新的靶点。方法:通过构建慢病毒颗粒感染结肠癌SW480细胞,采用免疫组织化学法、Western bolt、PCR技术检测TRPV6蛋白及m RNA的表达,MTT法、迁移及凋亡实验观察结肠癌SW480细胞增殖、迁移及凋亡变化,高速离子成像系统测定结肠癌SW480细胞内的Ca^(2+)浓度变化。以二甲基肼(dimethyl hydrazine,DMH)建立SD大鼠结肠肿瘤模型,分为实验组(DMH组)和干预组[(DMH+1,25(OH)_2D_3组、DMH+CuCl_2组)]、对照组,干预组分别予1,25(OH)_2D_3(37.5 nmol/kg)、CuCl2(375μmol/kg)对模型进行干预。观察各组大鼠结肠腺瘤及腺癌的发生情况,Western blot检测各组结肠组织中TRPV6蛋白的表达情况。结果:TRPV6-RNAi转染结肠癌SW480细胞后,TRPV6 m RNA及蛋白表达减少,细胞Ca^(2+)浓度水平降低,结肠癌SW480细胞的增殖率、迁移能力下降,细胞凋亡率增加,与空白对照组及阴性对照组比较差异具有统计学意义(P<0.05)。对照组大鼠成瘤率为0,DMH+1,25(OH)_2D_3组为100%,DMH组为84.62%,DMH+CuCl_2组为33.33%。各组大鼠大肠中均有TRPV6蛋白的表达,表达情况为DMH+1,25(OH)_2D_3组>DMH组>DMH+CuCl_2组>对照组,差异具有统计学意义(P<0.05)。结论:降低结肠癌SW480细胞Ca^(2+)浓度水平可抑制结肠癌SW480细胞的增殖、迁移能力,诱导细胞凋亡。1,25(OH)_2D_3可以增加实验鼠结肠组织TRPV6蛋白表达,促进结肠肿瘤的形成。CuCl_2可以使实验鼠结肠组织中的TRPV6蛋白表达降低,并抑制结肠肿瘤的形成。展开更多
The gut-brain axis is a bidirectional information interaction system between the central nervous system(CNS) and the gastrointestinal tract, in which gut microbiota plays a key role. The gut microbiota forms a complex...The gut-brain axis is a bidirectional information interaction system between the central nervous system(CNS) and the gastrointestinal tract, in which gut microbiota plays a key role. The gut microbiota forms a complex network with the enteric nervous system, the autonomic nervous system, and the neuroendocrine and neuroimmunity of the CNS, which is called the microbiota-gut-brain axis. Due to the close anatomical and functional interaction of the gut-liver axis, the microbiota-gut-liver-brain axis has attracted increased attention in recent years. The microbiota-gut-liver-brain axis mediates the occurrence and development of many diseases, and it offers a direction for the research of disease treatment. In this review, we mainly discuss the role of the gut microbiota in the irritable bowel syndrome, inflammatory bowel disease, functional dyspepsia, non-alcoholic fatty liver disease, alcoholic liver disease, cirrhosis and hepatic encephalopathy via the gut-liver-brain axis, and the focus is to clarify the potential mechanisms and treatment of digestive diseases based on the further understanding of the microbiota-gut-liver-brain axis.展开更多
Calcium carbonates are commonly administered as supplements for conditions of calcium deficiency.We report here pharmacokinetic characteristics of a novel formulation,calcium carbonate compound granules(CCCGs).forming...Calcium carbonates are commonly administered as supplements for conditions of calcium deficiency.We report here pharmacokinetic characteristics of a novel formulation,calcium carbonate compound granules(CCCGs).forming complexes of calcium carbonate and calcium citrate in water.CCCGs were compared to a kind of commonly?used calcium carbonate preparation(CC)in the market in 5-week-old mice that had been treated with omeprazole,to suppress gastric acid secretion,and in untreated control mice.The results showed that:(1)CCCGs had better water solubility than CC in vitro;(2)In control mice,calcium absorption rates after CCCGs administration were comparable to those after CC administration;(3)Inhibition of gastric acid secretion did not affect calcium absorption after CCCGs,but moderately decreased it after CC;(4)The presence of phytic acid or tannin did not affect calcium absorption rates after CCCGs but did for CC;and(5)In nonnal mice,CCCGs did not inhibit gastric emptying and intestinal propulsion,and did not alter the gastrointestinal honnones.The results suggest that CCCGs may be therapeutically advantageous over more commonly used calcium supplement formulations,particularly for adolescents,because of their stable calcium absorption characteristics and their relatively favorable adverse effect profile.展开更多
Graphene-based laminar materials open up to new applications for molecular and ionic separations in aqueous environments due to the atomic thickness, mechanical strength, chemical stability and other fantastic propert...Graphene-based laminar materials open up to new applications for molecular and ionic separations in aqueous environments due to the atomic thickness, mechanical strength, chemical stability and other fantastic properties.Recent advances on controlling the structure and chemical functionality of graphene-based membranes can potentially lead to new classes of tools for desalination, dehydration, toxicant rejection, specific ionic separation and so on. The recent developments of graphene-based membranes prepared by using a concept to form interlayer space between graphene sheets and creating nanoscale or sub-nanoscale pores in a graphene lattice, together with their mass-transfer mechanisms and potential applications in aqueous environments are reviewed. A summary and outlook is further provided on the opportunities and challenges in this arising field.This article is expected to address the intricate details of mass transport through two distinct graphene-based membranes in aqueous environment and to optimize the fabrication of graphene-based membranes as a fascinating separation system for a wide range of applications.展开更多
Neurofibromatosis type 1(NF-1) is commonly associated with benign or malignant tumors in both the central and peripheral nervous systems. However, rare cases of NF-1-associated multiplerectal neuroendocrine tumors hav...Neurofibromatosis type 1(NF-1) is commonly associated with benign or malignant tumors in both the central and peripheral nervous systems. However, rare cases of NF-1-associated multiplerectal neuroendocrine tumors have been reported. This report describes a case of a 39 year old female with NF-1 and intermittent hematochezia as a primary symptom. Physical examination showed multiple subcutaneous nodules and café au lait spots with obvious scoliosis of the back. Imaging examinations and colonoscopy found malformation of the left external iliac vein and multiple gray-yellow nodules with varying sizes and shapes in the rectal submucosal layer. Histological and immunohistochemical results suggested multiple rectal neuroendocrine tumors, a rare disease with few appreciable symptoms and a particularly poor prognosis. The patient with NF-1 presented here had not only multiple rectal neuroendocrine neoplasms but also vascular malformations, scoliosis and other multiple system lesions. This case therefore contributes to improving clinical understanding, diagnosis and treatment of related complications for patients with NF-1 who present with associated medical conditions.展开更多
The Na^+/Ca^(2+) exchanger(NCX) protein family is a part of the cation/Ca^(2+) exchanger superfamily and participates in the regulation of cellular Ca^(2+) homeostasis. NCX1, the most important subtype in the NCX fami...The Na^+/Ca^(2+) exchanger(NCX) protein family is a part of the cation/Ca^(2+) exchanger superfamily and participates in the regulation of cellular Ca^(2+) homeostasis. NCX1, the most important subtype in the NCX family, is expressed widely in various organs and tissues in mammals and plays an especially important role in the physiological and pathological processes of nerves and the cardiovascular system. In the past few years, the function of NCX1 in the digestive system has received increasing attention; NCX1 not only participates in the healing process of gastric ulcer and gastric mucosal injury but also mediates the development of digestive cancer, acute pancreatitis, and intestinal absorption.This review aims to explore the roles of NCX1 in digestive system physiology and pathophysiology in order to guide clinical treatments.展开更多
AIM: To investigate the relationship between cholecystectomy and fatty liver disease(FLD) in a Chinese population.METHODS: A total of 32428 subjects who had voluntarily undergone annual health checkups in the Second A...AIM: To investigate the relationship between cholecystectomy and fatty liver disease(FLD) in a Chinese population.METHODS: A total of 32428 subjects who had voluntarily undergone annual health checkups in the Second Affiliated Hospital of Nanjing Medical University from January 2011 to May 2013 were included in this study. Basic data collection, physical examination, laboratory examination, and abdominal ultrasound examination were performed.RESULTS: Subjects undergoing cholecystectomy were associated with greater age, female sex, higher body mass index, and higher levels of systolic blood pressure, diastolic blood pressure, fasting plasma glucose, total cholesterol, and triglycerides. However, no significant differences were found in high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, alanine aminotransferase, aspartate aminotransferase, gammaglutamyl transpeptidase, albumin, and serum uric acid. The overall prevalence of FLD diagnosed by ultrasonography was high at 38.4%. The prevalence of FLD was significantly higher for subjects who had undergone cholecystectomy(46.9%) than those who had not undergone cholecystectomy(38.1%; χ2 test, P < 0.001). Cholecystectomy was positively associated with FLD(OR = 1.433, 95%CI: 1.259-1.631). However, after adjusting for possible factors associated withFLD, multivariate regression analysis showed that the association between cholecystectomy and FLD was not statistically significant(OR = 1.096; 95%CI: 0.939-1.279). CONCLUSION: According to our study results, cholecystectomy may not be a significant risk factor for FLD.展开更多
The development of alternative renewable energy technologies is crucial for alleviating climate change and promoting energy transformation.Of the currently available technologies,solar energy has promising application...The development of alternative renewable energy technologies is crucial for alleviating climate change and promoting energy transformation.Of the currently available technologies,solar energy has promising application prospects owing to its merits of being clean,safe,and sustainable.Solar energy is converted into electricity through photovoltaic(PV)cells;however,the overall conversion efficiency of PV modules is relatively low,and most of the captured solar energy is dissipated in the form of heat.This not only reduces the power generation efficiency of solar cells but may also have a negative impact on the electrical parameters of PV modules and the service life of PV cells.To overcome the shortcomings,an efficient approach involves combining a PV cell with a thermoelectric generator(TEG)to form hybrid PV-TEG systems,which simultaneously improve the energy conversion efficiency of the PV system by reducing the operating temperature of the PV modules and increasing the power output by utilizing the waste heat generated from the PV system to generate electricity via the TEGs.Based on a thorough examination of the literature,this study comprehensively reviews 14 maximum power point tracking(MPPT)algorithms currently applied to hybrid PV-TEG systems and classifies them into five major categories for further discussion,namely conventional,mathematics-based,metaheuristic,artificial intelligence,and other algorithms.This review aims to inspire advanced ideas and research on MPPT algorithms for hybrid PV-TEG systems.展开更多
This work focuses on drop breakage for liquid-liquid system with an adoption of numerical simulation by using computational fluid dynamics and population balance model (PBM) coupled with two-fluid model (TFM). Two dif...This work focuses on drop breakage for liquid-liquid system with an adoption of numerical simulation by using computational fluid dynamics and population balance model (PBM) coupled with two-fluid model (TFM). Two different breakage kernels based on identical breakage mechanism but different descriptions of breaking time are take n into account in this work. Eight cases corresp on ding to distinct configurations of agitator are carried out to validate numerical predictions, namely agitators with different porosity and hole diameters, respectively implemented in Cases 1 to 5 and Cases 6 to 8. The results are compared with experimental data for testing the applicability of both kernels. Simulations are implemented, in this work, with an approach of class method for the solution of population balance model by the special-purpose computational fluid dynamics solver Fluent 16.1 based on finite volume method, and the grids used for meshing the solution domain are accomplished in a commercial software Gambit 2.4.6. The effects of configurations of agitator corresponding to different parameters mentioned above on final Sauter mean diameter are equally concentrated in this work. Analysis of both kernels and comparisons with experimental results reveal that, the second kernel has more decent agreement with experiments, and the results of investigations on effects of agitator configurations show that the in fluences of these parameters on Sauter mean diameter are marginal, but appropriate porosity and hole diameter are actually able to decrease Sauter mean diameter. These outcomes allow us to draw general conclusions and help investigate performances of liquid-liquid system.展开更多
BACKGROUND Ingestion of foreign bodies results in gastrointestinal perforation in approximately 1% of patients,and fish bones are the objects that most commonly lead to bowel perforation. When it does occur,the termin...BACKGROUND Ingestion of foreign bodies results in gastrointestinal perforation in approximately 1% of patients,and fish bones are the objects that most commonly lead to bowel perforation. When it does occur,the terminal ileum is the most common site of perforation,followed by the duodenal C-loop. However,involvement of the pancreas is very rare. Because clinical symptoms are nonspecific and gastrointestinal perforation may present as only odynophagia or abdominal pain,a definite preoperative diagnosis and clinical intervention may be delayed.CASE SUMMARY We report the case of a 32-year-old man who presented to our hospital because of abdominal pain that had worsened over 5 d. He had no significant past history except that he had eaten fish 1 wk previously. Upper endoscopy revealed an irregular submucosal tumor on the front wall of the gastric antrum. Endoscopic ultrasonography and computed tomography showed a fish bone penetrating the gastric antrum and migratingin to the neck of the pancreas. The patient underwent laparoscopic surgery and had no complications one week after the operation.CONCLUSION A recent history of foreign body ingestion and imaging examinations are helpful for diagnosis of unexplained abdominal pain caused by foreign bodies.展开更多
基金supported by the National Natural Science Foundation of China[grant number 81970987].
文摘The use of robots to augment human capabilities and assist in work has long been an aspiration.Robotics has been developing since the 1960s when the first industrial robot was introduced.As technology has advanced,robotic-assisted surgery has shown numerous advantages,including more precision,efficiency,minimal invasiveness,and safety than is possible with conventional techniques,which are research hotspots and cutting-edge trends.This article reviewed the history of medical robot development and seminal research papers about current research progress.Taking the autonomous dental implant robotic system as an example,the advantages and prospects of medical robotic systems would be discussed which would provide a reference for future research.
基金supported by National Natural Science Foundation of China(No.81970987).
文摘Accurate segmentation of oral surgery-related tissues from cone beam computed tomography(CBCT)images can significantly accelerate treatment planning and improve surgical accuracy.In this paper,we propose a fully automated tissue segmentation system for dental implant surgery.Specifically,we propose an image preprocessing method based on data distribution histograms,which can adaptively process CBCT images with different parameters.Based on this,we use the bone segmentation network to obtain the segmentation results of alveolar bone,teeth,and maxillary sinus.We use the tooth and mandibular regions as the ROI regions of tooth segmentation and mandibular nerve tube segmentation to achieve the corresponding tasks.The tooth segmentation results can obtain the order information of the dentition.The corresponding experimental results show that our method can achieve higher segmentation accuracy and efficiency compared to existing methods.Its average Dice scores on the tooth,alveolar bone,maxillary sinus,and mandibular canal segmentation tasks were 96.5%,95.4%,93.6%,and 94.8%,respectively.These results demonstrate that it can accelerate the development of digital dentistry.
基金funding from the Open Fund Project of Intelligent Electric Power Grid Key Laboratory of Sichuan Province under Grant(2023-IEPGKLSP-KFYB03)Yunnan Provincial Basic Research Project(202301AT070443).
文摘Maximum power point tracking(MPPT)technology plays a key role in improving the energy conversion efficiency of photovoltaic(PV)systems,especially when multiple local maximum power points(LMPPs)occur under partial shading conditions(PSC).It is necessary to modify the operating point efficiently and accurately with the help of MPPT technology to maximize the collected power.Even though a lot of research has been carried out and impressive progress achieved for MPPT technology,it still faces some challenges and dilemmas.Firstly,the mathematical model established for PV cells is not precise enough.Second,the existing algorithms are often optimized for specific conditions and lack comprehensive adaptability to the actual operating environment.Besides,a single algorithm may not be able to give full play to its advantages.In the end,the selection criteria for choosing the suitable MPPT algorithm/converter combination to achieve better performance in a given scenario is very limited.Therefore,this paper systematically discusses the current research status and challenges faced by PV MPPT technology around the three aspects of MPPT models,algorithms,and hardware implementation.Through in-depth thinking and discussion,it also puts forward positive perspectives on future development,and five forward-looking solutions to improve the performance of PV systems MPPT are suggested.
文摘目的:通过观察沉默瞬时受体阳离子通道亚家族V成员6(transient receptor potential cation channel,subfamily V member 6,TRPV6)对结肠癌SW480细胞生物学行为的影响和细胞内钙的浓度变化,以及1,25(OH)_2D_3、CaCl_2及CuCl_2在SD大鼠结肠肿瘤模型建立中的影响,探索TRPV6在结肠癌发生过程中的相关作用,为结肠癌的防治寻找新的靶点。方法:通过构建慢病毒颗粒感染结肠癌SW480细胞,采用免疫组织化学法、Western bolt、PCR技术检测TRPV6蛋白及m RNA的表达,MTT法、迁移及凋亡实验观察结肠癌SW480细胞增殖、迁移及凋亡变化,高速离子成像系统测定结肠癌SW480细胞内的Ca^(2+)浓度变化。以二甲基肼(dimethyl hydrazine,DMH)建立SD大鼠结肠肿瘤模型,分为实验组(DMH组)和干预组[(DMH+1,25(OH)_2D_3组、DMH+CuCl_2组)]、对照组,干预组分别予1,25(OH)_2D_3(37.5 nmol/kg)、CuCl2(375μmol/kg)对模型进行干预。观察各组大鼠结肠腺瘤及腺癌的发生情况,Western blot检测各组结肠组织中TRPV6蛋白的表达情况。结果:TRPV6-RNAi转染结肠癌SW480细胞后,TRPV6 m RNA及蛋白表达减少,细胞Ca^(2+)浓度水平降低,结肠癌SW480细胞的增殖率、迁移能力下降,细胞凋亡率增加,与空白对照组及阴性对照组比较差异具有统计学意义(P<0.05)。对照组大鼠成瘤率为0,DMH+1,25(OH)_2D_3组为100%,DMH组为84.62%,DMH+CuCl_2组为33.33%。各组大鼠大肠中均有TRPV6蛋白的表达,表达情况为DMH+1,25(OH)_2D_3组>DMH组>DMH+CuCl_2组>对照组,差异具有统计学意义(P<0.05)。结论:降低结肠癌SW480细胞Ca^(2+)浓度水平可抑制结肠癌SW480细胞的增殖、迁移能力,诱导细胞凋亡。1,25(OH)_2D_3可以增加实验鼠结肠组织TRPV6蛋白表达,促进结肠肿瘤的形成。CuCl_2可以使实验鼠结肠组织中的TRPV6蛋白表达降低,并抑制结肠肿瘤的形成。
基金Supported by the National Natural Science Foundation of China,No. 81970541,No. 31960151,No. 81660099 and No. 81660412。
文摘The gut-brain axis is a bidirectional information interaction system between the central nervous system(CNS) and the gastrointestinal tract, in which gut microbiota plays a key role. The gut microbiota forms a complex network with the enteric nervous system, the autonomic nervous system, and the neuroendocrine and neuroimmunity of the CNS, which is called the microbiota-gut-brain axis. Due to the close anatomical and functional interaction of the gut-liver axis, the microbiota-gut-liver-brain axis has attracted increased attention in recent years. The microbiota-gut-liver-brain axis mediates the occurrence and development of many diseases, and it offers a direction for the research of disease treatment. In this review, we mainly discuss the role of the gut microbiota in the irritable bowel syndrome, inflammatory bowel disease, functional dyspepsia, non-alcoholic fatty liver disease, alcoholic liver disease, cirrhosis and hepatic encephalopathy via the gut-liver-brain axis, and the focus is to clarify the potential mechanisms and treatment of digestive diseases based on the further understanding of the microbiota-gut-liver-brain axis.
文摘Calcium carbonates are commonly administered as supplements for conditions of calcium deficiency.We report here pharmacokinetic characteristics of a novel formulation,calcium carbonate compound granules(CCCGs).forming complexes of calcium carbonate and calcium citrate in water.CCCGs were compared to a kind of commonly?used calcium carbonate preparation(CC)in the market in 5-week-old mice that had been treated with omeprazole,to suppress gastric acid secretion,and in untreated control mice.The results showed that:(1)CCCGs had better water solubility than CC in vitro;(2)In control mice,calcium absorption rates after CCCGs administration were comparable to those after CC administration;(3)Inhibition of gastric acid secretion did not affect calcium absorption after CCCGs,but moderately decreased it after CC;(4)The presence of phytic acid or tannin did not affect calcium absorption rates after CCCGs but did for CC;and(5)In nonnal mice,CCCGs did not inhibit gastric emptying and intestinal propulsion,and did not alter the gastrointestinal honnones.The results suggest that CCCGs may be therapeutically advantageous over more commonly used calcium supplement formulations,particularly for adolescents,because of their stable calcium absorption characteristics and their relatively favorable adverse effect profile.
基金Supported by the National Natural Science Foundation of China(21490582,21506127)
文摘Graphene-based laminar materials open up to new applications for molecular and ionic separations in aqueous environments due to the atomic thickness, mechanical strength, chemical stability and other fantastic properties.Recent advances on controlling the structure and chemical functionality of graphene-based membranes can potentially lead to new classes of tools for desalination, dehydration, toxicant rejection, specific ionic separation and so on. The recent developments of graphene-based membranes prepared by using a concept to form interlayer space between graphene sheets and creating nanoscale or sub-nanoscale pores in a graphene lattice, together with their mass-transfer mechanisms and potential applications in aqueous environments are reviewed. A summary and outlook is further provided on the opportunities and challenges in this arising field.This article is expected to address the intricate details of mass transport through two distinct graphene-based membranes in aqueous environment and to optimize the fabrication of graphene-based membranes as a fascinating separation system for a wide range of applications.
文摘Neurofibromatosis type 1(NF-1) is commonly associated with benign or malignant tumors in both the central and peripheral nervous systems. However, rare cases of NF-1-associated multiplerectal neuroendocrine tumors have been reported. This report describes a case of a 39 year old female with NF-1 and intermittent hematochezia as a primary symptom. Physical examination showed multiple subcutaneous nodules and café au lait spots with obvious scoliosis of the back. Imaging examinations and colonoscopy found malformation of the left external iliac vein and multiple gray-yellow nodules with varying sizes and shapes in the rectal submucosal layer. Histological and immunohistochemical results suggested multiple rectal neuroendocrine tumors, a rare disease with few appreciable symptoms and a particularly poor prognosis. The patient with NF-1 presented here had not only multiple rectal neuroendocrine neoplasms but also vascular malformations, scoliosis and other multiple system lesions. This case therefore contributes to improving clinical understanding, diagnosis and treatment of related complications for patients with NF-1 who present with associated medical conditions.
基金Supported by the National Natural Science Foundation of China,No.816660412 to Xie R and No.81160265 to Xu JY
文摘The Na^+/Ca^(2+) exchanger(NCX) protein family is a part of the cation/Ca^(2+) exchanger superfamily and participates in the regulation of cellular Ca^(2+) homeostasis. NCX1, the most important subtype in the NCX family, is expressed widely in various organs and tissues in mammals and plays an especially important role in the physiological and pathological processes of nerves and the cardiovascular system. In the past few years, the function of NCX1 in the digestive system has received increasing attention; NCX1 not only participates in the healing process of gastric ulcer and gastric mucosal injury but also mediates the development of digestive cancer, acute pancreatitis, and intestinal absorption.This review aims to explore the roles of NCX1 in digestive system physiology and pathophysiology in order to guide clinical treatments.
文摘AIM: To investigate the relationship between cholecystectomy and fatty liver disease(FLD) in a Chinese population.METHODS: A total of 32428 subjects who had voluntarily undergone annual health checkups in the Second Affiliated Hospital of Nanjing Medical University from January 2011 to May 2013 were included in this study. Basic data collection, physical examination, laboratory examination, and abdominal ultrasound examination were performed.RESULTS: Subjects undergoing cholecystectomy were associated with greater age, female sex, higher body mass index, and higher levels of systolic blood pressure, diastolic blood pressure, fasting plasma glucose, total cholesterol, and triglycerides. However, no significant differences were found in high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, alanine aminotransferase, aspartate aminotransferase, gammaglutamyl transpeptidase, albumin, and serum uric acid. The overall prevalence of FLD diagnosed by ultrasonography was high at 38.4%. The prevalence of FLD was significantly higher for subjects who had undergone cholecystectomy(46.9%) than those who had not undergone cholecystectomy(38.1%; χ2 test, P < 0.001). Cholecystectomy was positively associated with FLD(OR = 1.433, 95%CI: 1.259-1.631). However, after adjusting for possible factors associated withFLD, multivariate regression analysis showed that the association between cholecystectomy and FLD was not statistically significant(OR = 1.096; 95%CI: 0.939-1.279). CONCLUSION: According to our study results, cholecystectomy may not be a significant risk factor for FLD.
基金This work was supported by National Natural Science Foundation of China(61963020,62263014)Yunnan Provincial Basic Research Project(202201AT070857).
文摘The development of alternative renewable energy technologies is crucial for alleviating climate change and promoting energy transformation.Of the currently available technologies,solar energy has promising application prospects owing to its merits of being clean,safe,and sustainable.Solar energy is converted into electricity through photovoltaic(PV)cells;however,the overall conversion efficiency of PV modules is relatively low,and most of the captured solar energy is dissipated in the form of heat.This not only reduces the power generation efficiency of solar cells but may also have a negative impact on the electrical parameters of PV modules and the service life of PV cells.To overcome the shortcomings,an efficient approach involves combining a PV cell with a thermoelectric generator(TEG)to form hybrid PV-TEG systems,which simultaneously improve the energy conversion efficiency of the PV system by reducing the operating temperature of the PV modules and increasing the power output by utilizing the waste heat generated from the PV system to generate electricity via the TEGs.Based on a thorough examination of the literature,this study comprehensively reviews 14 maximum power point tracking(MPPT)algorithms currently applied to hybrid PV-TEG systems and classifies them into five major categories for further discussion,namely conventional,mathematics-based,metaheuristic,artificial intelligence,and other algorithms.This review aims to inspire advanced ideas and research on MPPT algorithms for hybrid PV-TEG systems.
基金Supported by the National Natural Science Foundation of China(21776180,21306116)
文摘This work focuses on drop breakage for liquid-liquid system with an adoption of numerical simulation by using computational fluid dynamics and population balance model (PBM) coupled with two-fluid model (TFM). Two different breakage kernels based on identical breakage mechanism but different descriptions of breaking time are take n into account in this work. Eight cases corresp on ding to distinct configurations of agitator are carried out to validate numerical predictions, namely agitators with different porosity and hole diameters, respectively implemented in Cases 1 to 5 and Cases 6 to 8. The results are compared with experimental data for testing the applicability of both kernels. Simulations are implemented, in this work, with an approach of class method for the solution of population balance model by the special-purpose computational fluid dynamics solver Fluent 16.1 based on finite volume method, and the grids used for meshing the solution domain are accomplished in a commercial software Gambit 2.4.6. The effects of configurations of agitator corresponding to different parameters mentioned above on final Sauter mean diameter are equally concentrated in this work. Analysis of both kernels and comparisons with experimental results reveal that, the second kernel has more decent agreement with experiments, and the results of investigations on effects of agitator configurations show that the in fluences of these parameters on Sauter mean diameter are marginal, but appropriate porosity and hole diameter are actually able to decrease Sauter mean diameter. These outcomes allow us to draw general conclusions and help investigate performances of liquid-liquid system.
文摘BACKGROUND Ingestion of foreign bodies results in gastrointestinal perforation in approximately 1% of patients,and fish bones are the objects that most commonly lead to bowel perforation. When it does occur,the terminal ileum is the most common site of perforation,followed by the duodenal C-loop. However,involvement of the pancreas is very rare. Because clinical symptoms are nonspecific and gastrointestinal perforation may present as only odynophagia or abdominal pain,a definite preoperative diagnosis and clinical intervention may be delayed.CASE SUMMARY We report the case of a 32-year-old man who presented to our hospital because of abdominal pain that had worsened over 5 d. He had no significant past history except that he had eaten fish 1 wk previously. Upper endoscopy revealed an irregular submucosal tumor on the front wall of the gastric antrum. Endoscopic ultrasonography and computed tomography showed a fish bone penetrating the gastric antrum and migratingin to the neck of the pancreas. The patient underwent laparoscopic surgery and had no complications one week after the operation.CONCLUSION A recent history of foreign body ingestion and imaging examinations are helpful for diagnosis of unexplained abdominal pain caused by foreign bodies.