Screw conveyors are widely used for bulk material transportation.This study investigates the critical role of radial clearance,the gap between the screw and the conveyor body,on performance across various inclination ...Screw conveyors are widely used for bulk material transportation.This study investigates the critical role of radial clearance,the gap between the screw and the conveyor body,on performance across various inclination angles.The Discrete Element Method(DEM)is employed to analyze the effects of different radial clearances on conveyor performance for concrete aggregate and sand as bulk materials.Volumetric efficiencies and capacity losses serve as key performance indicators,quantitatively assessed for each radial clearance and inclination combination.Experimental validation is conducted to corroborate the findings.In the study,the optimal radial clearance was identified as 1.5 to 3 times of the particle size.This optimal clearance minimizes the material jamming and increases the performance for screw conveyors with different inclinations and bulk material types as a result.展开更多
Advancements in murine modeling systems for ulcerative colitis have diversified our understanding of the pathophysiological factors involved in disease onset and progression.This has fueled the identification of molec...Advancements in murine modeling systems for ulcerative colitis have diversified our understanding of the pathophysiological factors involved in disease onset and progression.This has fueled the identification of molecular targets,resulting in a rapidly expanding therapeutic armamentarium.Subsequently,management strategies have evolved from symptomatic resolution to well-defined objective endpoints,including clinical remission,endoscopic remission and mucosal healing.While the incorporation of these assessment modalities has permitted targeted intervention in the context of a natural disease history and the prevention of complications,studies have consistently depicted discrepancies associated with ascertaining disease status through clinical and endoscopic measures.Current recommendations lack consideration of histological healing.The simultaneous achievement of clinical,endoscopic,and histologic remission has not been fully investigated.This has laid the groundwork for a novel therapeutic outcome termed disease clearance(DC).This article summarizes the concept of DC and its current evidence.展开更多
Alzheimer's disease,the primary cause of dementia,is characterized by neuropathologies,such as amyloid plaques,synaptic and neuronal degeneration,and neurofibrillary tangles.Although amyloid plaques are the primar...Alzheimer's disease,the primary cause of dementia,is characterized by neuropathologies,such as amyloid plaques,synaptic and neuronal degeneration,and neurofibrillary tangles.Although amyloid plaques are the primary characteristic of Alzheimer's disease in the central nervous system and peripheral organs,targeting amyloid-beta clearance in the central nervous system has shown limited clinical efficacy in Alzheimer's disease treatment.Metabolic abnormalities are commonly observed in patients with Alzheimer's disease.The liver is the primary peripheral organ involved in amyloid-beta metabolism,playing a crucial role in the pathophysiology of Alzheimer's disease.Notably,impaired cholesterol metabolism in the liver may exacerbate the development of Alzheimer's disease.In this review,we explore the underlying causes of Alzheimer's disease and elucidate the role of the liver in amyloid-beta clearance and cholesterol metabolism.Furthermore,we propose that restoring normal cholesterol metabolism in the liver could represent a promising therapeutic strategy for addressing Alzheimer's disease.展开更多
This study develops a procedure to rank agencies based on their incident responses using roadway clearance times for crashes. This analysis is not intended to grade agencies but to assist in identifying agencies requi...This study develops a procedure to rank agencies based on their incident responses using roadway clearance times for crashes. This analysis is not intended to grade agencies but to assist in identifying agencies requiring more training or resources for incident management. Previous NCHRP reports discussed usage of different factors including incident severity, roadway characteristics, number of lanes involved and time of incident separately for estimating the performance. However, it does not tell us how to incorporate all the factors at the same time. Thus, this study aims to account for multiple factors to ensure fair comparisons. This study used 149,174 crashes from Iowa that occurred from 2018 to 2021. A Tobit regression model was used to find the effect of different variables on roadway clearance time. Variables that cannot be controlled directly by agencies such as crash severity, roadway type, weather conditions, lighting conditions, etc., were included in the analysis as it helps to reduce bias in the ranking procedure. Then clearance time of each crash is normalized into a base condition using the regression coefficients. The normalization makes the process more efficient as the effect of uncontrollable factors has already been mitigated. Finally, the agencies were ranked by their average normalized roadway clearance time. This ranking process allows agencies to track their performance of previous crashes, can be used in identifying low performing agencies that could use additional resources and training, and can be used to identify high performing agencies to recognize for their efforts and performance.展开更多
Introduction: Breast cancer is the number one malignancy affecting females in Saudi Arabia with a prevalence of 22.4%. Breast cancer incidence increases annually due to the aid of established screening programs, leadi...Introduction: Breast cancer is the number one malignancy affecting females in Saudi Arabia with a prevalence of 22.4%. Breast cancer incidence increases annually due to the aid of established screening programs, leading to the discovery of breast cancer in its early stages. Surgical treatment is an integral part of early breast cancer management to achieve local control. Axillary surgical interventions such sentinel lymph node biopsy (SLNB) and axillary lymph node clearance (ALND) aim to stage the axilla as an adjunct to the management of the primary breast tumor. In this paper, we reviewed female breast cancer patients aged 30 - 60 who underwent surgical treatment of SLNB and/or ALND with reporting the prevalence of lymphedema and other associated complications and risk factors. Methodology: A cross-sectional non-interventional study, with a sample size of 250 including breast cancer cases from 2016 to 2019 at National Guard Hospital (NGH) in Jeddah, Saudi Arabia. Results: A total of 253 breast cancer cases were included in this study, with a mean age of 53 years, 52.7% were postmenopausal and positive family history was present among 21% of cases. Further, 90.9% of the cases had unilateral disease. Staging was as follows: stage I 14.5%, stage II 45.2%, stage III 37.1%, and stage IV 3.2%. Mastectomy was done in 73.4% cases and lumpectomy was performed in 34.1% of cases. In addition, 93.3% of patients had SLNB and 49% of them were positive. Axillary dissection was performed in 69.6% of our patients. Radiotherapy and chemotherapy were given to 71.8% and 80.4% of cases respectively. Among the chemotherapy (chemo) recipients, 40.2% received adjuvant chemo, 54.5% received neoadjuvant chemo, and the remaining 5.3% received both. Further, the most prevalent complication was pain accounting for 42.1% of total complications, and the least prevalent was cellulitis 4%. Also, seroma developed in 18.3% cases, paresthesia noted in 5.6% of cases, winged scapula was reported as 2%, weakness and necrosis were seen in 6% and 13.1% of cases respectively. Axillary vein thrombosis and lymphangiosarcoma were reported in none of the patients (0%). Lymphoedema accounted for 16.1% of overall complications, 85% of the patients who developed lymphedema had undergone ALND, and 12.9% and 14.4% received radiotherapy and chemotherapy respectively. Lymphedema was observed in breast cancer stages as follows: stage I 1.2%, stage II 7.2%, and stage III 5.2%. Patients with body mass index (BMI) of 30 - 39 kg/m<sup>2</sup> had 7.2% prevalence of lymphedema compared to other BMI groups. Overall mortality was 8.3%. Conclusion: The findings of our study suggest that the prevalence of lymphedema was higher in ALND patients with locally advanced tumors, and higher BMI, compared to patients with stage I breast cancer and low BMI. Further, the prevalence of lymphedema in patients who underwent ALND was significantly lower than those who were treated by lumpectomy 10.3% (p-value = 0.034) in comparison to mastectomy 19.3%.展开更多
Clearances in joints of a mechanical multibody system can induce impulsive forces, leading to vibrations that compromise the system’s reliability, stability, and lifespan. Through dynamic analysis, designers can inve...Clearances in joints of a mechanical multibody system can induce impulsive forces, leading to vibrations that compromise the system’s reliability, stability, and lifespan. Through dynamic analysis, designers can investigate the effects of the clearances on the dynamics of the multibody system. A revolute joint with clearance exhibits three motions which are;free-flight, impact and continuous contact motion modes. Therefore, a multibody system with n-number of revolute clearance joints will exhibit 3n motion modes which are a combination of the three motions in each joint. This study investigates experimentally the nine motion modes in a mechanical system with two revolute clearance joints. A slider crank mechanism has been used as the demonstrative example. We observed that the experimental curve exhibits a greater impact compared to the simulation curve. In conclusion, this experimental investigation offers valuable insights into the dynamics of planar mechanical systems with multiple clearance revolute joints. Utilizing a slider-crank mechanism for data acquisition, the study successfully confirmed seven out of nine motion modes previously identified in numerical research. The missing modes are attributed to inherent complexities in real-world systems, such as journal-bearing misalignment.展开更多
Objective:To study the predictive value of serum pregenomic RNA(pgRNA)on HBeAg clearance in patients with chronic hepatitis B with low HBeAg levels during pegylated interferon therapy.Methods:Twenty chronic hepatitis ...Objective:To study the predictive value of serum pregenomic RNA(pgRNA)on HBeAg clearance in patients with chronic hepatitis B with low HBeAg levels during pegylated interferon therapy.Methods:Twenty chronic hepatitis B patients with HBeAg positive and quantitative<50S/CO were selected for this study.The subjects underwent pegylated interferon therapy for 48-96 weeks and were followed up in the outpatient clinic after treatment.The patients were then divided into groups based on whether their HbeAg turned negative.The predictive ability of each indicator for HBeAg negative conversion was evaluated in the HBeAg negative group and the HBeAg positive group.Results:The results of logistic regression analysis suggested that pgRNA and HBcrAg were better indicators for predicting the clearance of HBeAg after treatment.Conclusion:For patients with chronic hepatitis B with low HBeAg levels,pgRNA is a good indicator in predicting HBeAg clearance during pegylated interferon therapy.展开更多
In the present work, for the first time, the main details of the electronic mechanism of the synergistic antioxidant interaction between different pairs: phenolic food acid and glutathione and the stable radical catio...In the present work, for the first time, the main details of the electronic mechanism of the synergistic antioxidant interaction between different pairs: phenolic food acid and glutathione and the stable radical cation ABTS<sup>+·</sup> were revealed on the basis of a rigorous analysis of the DFT calculated data. It was shown that among all the studied food acids, only caffeic acid exhibits a clear-cut significant synergistic effect with glutathione. It established the electronic and structural factors underlying the mechanism of the synergistic interaction of the mixture caffeic acid and glutathione in its reaction with ABTS<sup>+·</sup>. The main causes of this considered synergistic effect are, firstly, the presence of the 3-OH and 4-OH hydroxyl groups in the structure of caffeic acid, secondly, the greater stability of its anion which contains the deprotonated 4-OH hydroxyl group. All other phenolic food acids under study do not possess the given structural particularity and therefore do not show such synergistic effects with glutathione.展开更多
This article describes the effects of some factors on the tip clearance flow in axial linear turbine cascades. The measurements of the total pressure loss coefficient are made at the cascade outlets by using a five-ho...This article describes the effects of some factors on the tip clearance flow in axial linear turbine cascades. The measurements of the total pressure loss coefficient are made at the cascade outlets by using a five-hole probe at exit Mach numbers of 0.10, 0.14 and 0.19. At each exit Mach number, experiments are performed at the tip clearance heights of 1.0%, 1.5%, 2.0%, 2.5% and 3.0% of the blade height. The effects of the non-uniform tip clearance height of each blade in the pitchwise direction are also studied. The results show that at a given tip clearance height, generally, total pressure loss rises with exit Mach numbers proportionally. At a fixed exit Mach number, the total pressure loss augments nearly proportionally as the tip clearance height increases. The increased tip clearance heights in the tip regions of two adjacent blades are to be blame for the larger clearance loss of the center blade. Compared to the effects of the tip clearance height, the effects of the exit Mach number and the pitchwise variation of the tip clearance height on the cascade total pressure loss are so less significant to be omitted.展开更多
文摘Screw conveyors are widely used for bulk material transportation.This study investigates the critical role of radial clearance,the gap between the screw and the conveyor body,on performance across various inclination angles.The Discrete Element Method(DEM)is employed to analyze the effects of different radial clearances on conveyor performance for concrete aggregate and sand as bulk materials.Volumetric efficiencies and capacity losses serve as key performance indicators,quantitatively assessed for each radial clearance and inclination combination.Experimental validation is conducted to corroborate the findings.In the study,the optimal radial clearance was identified as 1.5 to 3 times of the particle size.This optimal clearance minimizes the material jamming and increases the performance for screw conveyors with different inclinations and bulk material types as a result.
文摘Advancements in murine modeling systems for ulcerative colitis have diversified our understanding of the pathophysiological factors involved in disease onset and progression.This has fueled the identification of molecular targets,resulting in a rapidly expanding therapeutic armamentarium.Subsequently,management strategies have evolved from symptomatic resolution to well-defined objective endpoints,including clinical remission,endoscopic remission and mucosal healing.While the incorporation of these assessment modalities has permitted targeted intervention in the context of a natural disease history and the prevention of complications,studies have consistently depicted discrepancies associated with ascertaining disease status through clinical and endoscopic measures.Current recommendations lack consideration of histological healing.The simultaneous achievement of clinical,endoscopic,and histologic remission has not been fully investigated.This has laid the groundwork for a novel therapeutic outcome termed disease clearance(DC).This article summarizes the concept of DC and its current evidence.
基金financially supported by the Science and Technology Innovation Program of Hunan Province,No.2022RC1220(to WP)China Postdoctoral Science Foundation,No.2022M711733(to ZZ)+2 种基金the National Natural Science Foundation of China,No.82160920(to ZZ)Hebei Postdoctoral Scientific Research Project,No.B2022003040(to ZZ)Hunan Flagship Department of Integrated Traditional Chinese and Western Medicine(to WP)。
文摘Alzheimer's disease,the primary cause of dementia,is characterized by neuropathologies,such as amyloid plaques,synaptic and neuronal degeneration,and neurofibrillary tangles.Although amyloid plaques are the primary characteristic of Alzheimer's disease in the central nervous system and peripheral organs,targeting amyloid-beta clearance in the central nervous system has shown limited clinical efficacy in Alzheimer's disease treatment.Metabolic abnormalities are commonly observed in patients with Alzheimer's disease.The liver is the primary peripheral organ involved in amyloid-beta metabolism,playing a crucial role in the pathophysiology of Alzheimer's disease.Notably,impaired cholesterol metabolism in the liver may exacerbate the development of Alzheimer's disease.In this review,we explore the underlying causes of Alzheimer's disease and elucidate the role of the liver in amyloid-beta clearance and cholesterol metabolism.Furthermore,we propose that restoring normal cholesterol metabolism in the liver could represent a promising therapeutic strategy for addressing Alzheimer's disease.
文摘This study develops a procedure to rank agencies based on their incident responses using roadway clearance times for crashes. This analysis is not intended to grade agencies but to assist in identifying agencies requiring more training or resources for incident management. Previous NCHRP reports discussed usage of different factors including incident severity, roadway characteristics, number of lanes involved and time of incident separately for estimating the performance. However, it does not tell us how to incorporate all the factors at the same time. Thus, this study aims to account for multiple factors to ensure fair comparisons. This study used 149,174 crashes from Iowa that occurred from 2018 to 2021. A Tobit regression model was used to find the effect of different variables on roadway clearance time. Variables that cannot be controlled directly by agencies such as crash severity, roadway type, weather conditions, lighting conditions, etc., were included in the analysis as it helps to reduce bias in the ranking procedure. Then clearance time of each crash is normalized into a base condition using the regression coefficients. The normalization makes the process more efficient as the effect of uncontrollable factors has already been mitigated. Finally, the agencies were ranked by their average normalized roadway clearance time. This ranking process allows agencies to track their performance of previous crashes, can be used in identifying low performing agencies that could use additional resources and training, and can be used to identify high performing agencies to recognize for their efforts and performance.
文摘Introduction: Breast cancer is the number one malignancy affecting females in Saudi Arabia with a prevalence of 22.4%. Breast cancer incidence increases annually due to the aid of established screening programs, leading to the discovery of breast cancer in its early stages. Surgical treatment is an integral part of early breast cancer management to achieve local control. Axillary surgical interventions such sentinel lymph node biopsy (SLNB) and axillary lymph node clearance (ALND) aim to stage the axilla as an adjunct to the management of the primary breast tumor. In this paper, we reviewed female breast cancer patients aged 30 - 60 who underwent surgical treatment of SLNB and/or ALND with reporting the prevalence of lymphedema and other associated complications and risk factors. Methodology: A cross-sectional non-interventional study, with a sample size of 250 including breast cancer cases from 2016 to 2019 at National Guard Hospital (NGH) in Jeddah, Saudi Arabia. Results: A total of 253 breast cancer cases were included in this study, with a mean age of 53 years, 52.7% were postmenopausal and positive family history was present among 21% of cases. Further, 90.9% of the cases had unilateral disease. Staging was as follows: stage I 14.5%, stage II 45.2%, stage III 37.1%, and stage IV 3.2%. Mastectomy was done in 73.4% cases and lumpectomy was performed in 34.1% of cases. In addition, 93.3% of patients had SLNB and 49% of them were positive. Axillary dissection was performed in 69.6% of our patients. Radiotherapy and chemotherapy were given to 71.8% and 80.4% of cases respectively. Among the chemotherapy (chemo) recipients, 40.2% received adjuvant chemo, 54.5% received neoadjuvant chemo, and the remaining 5.3% received both. Further, the most prevalent complication was pain accounting for 42.1% of total complications, and the least prevalent was cellulitis 4%. Also, seroma developed in 18.3% cases, paresthesia noted in 5.6% of cases, winged scapula was reported as 2%, weakness and necrosis were seen in 6% and 13.1% of cases respectively. Axillary vein thrombosis and lymphangiosarcoma were reported in none of the patients (0%). Lymphoedema accounted for 16.1% of overall complications, 85% of the patients who developed lymphedema had undergone ALND, and 12.9% and 14.4% received radiotherapy and chemotherapy respectively. Lymphedema was observed in breast cancer stages as follows: stage I 1.2%, stage II 7.2%, and stage III 5.2%. Patients with body mass index (BMI) of 30 - 39 kg/m<sup>2</sup> had 7.2% prevalence of lymphedema compared to other BMI groups. Overall mortality was 8.3%. Conclusion: The findings of our study suggest that the prevalence of lymphedema was higher in ALND patients with locally advanced tumors, and higher BMI, compared to patients with stage I breast cancer and low BMI. Further, the prevalence of lymphedema in patients who underwent ALND was significantly lower than those who were treated by lumpectomy 10.3% (p-value = 0.034) in comparison to mastectomy 19.3%.
文摘Clearances in joints of a mechanical multibody system can induce impulsive forces, leading to vibrations that compromise the system’s reliability, stability, and lifespan. Through dynamic analysis, designers can investigate the effects of the clearances on the dynamics of the multibody system. A revolute joint with clearance exhibits three motions which are;free-flight, impact and continuous contact motion modes. Therefore, a multibody system with n-number of revolute clearance joints will exhibit 3n motion modes which are a combination of the three motions in each joint. This study investigates experimentally the nine motion modes in a mechanical system with two revolute clearance joints. A slider crank mechanism has been used as the demonstrative example. We observed that the experimental curve exhibits a greater impact compared to the simulation curve. In conclusion, this experimental investigation offers valuable insights into the dynamics of planar mechanical systems with multiple clearance revolute joints. Utilizing a slider-crank mechanism for data acquisition, the study successfully confirmed seven out of nine motion modes previously identified in numerical research. The missing modes are attributed to inherent complexities in real-world systems, such as journal-bearing misalignment.
基金the grant from SPPH Incubator Fund for Development of Science and Technology(2021YJY-19)SPPH Foundation for Development of Science and Technology(2021BJ-26)International Science and Technology Cooperation Projects of Shaanxi Province(2022KW-14).
文摘Objective:To study the predictive value of serum pregenomic RNA(pgRNA)on HBeAg clearance in patients with chronic hepatitis B with low HBeAg levels during pegylated interferon therapy.Methods:Twenty chronic hepatitis B patients with HBeAg positive and quantitative<50S/CO were selected for this study.The subjects underwent pegylated interferon therapy for 48-96 weeks and were followed up in the outpatient clinic after treatment.The patients were then divided into groups based on whether their HbeAg turned negative.The predictive ability of each indicator for HBeAg negative conversion was evaluated in the HBeAg negative group and the HBeAg positive group.Results:The results of logistic regression analysis suggested that pgRNA and HBcrAg were better indicators for predicting the clearance of HBeAg after treatment.Conclusion:For patients with chronic hepatitis B with low HBeAg levels,pgRNA is a good indicator in predicting HBeAg clearance during pegylated interferon therapy.
文摘In the present work, for the first time, the main details of the electronic mechanism of the synergistic antioxidant interaction between different pairs: phenolic food acid and glutathione and the stable radical cation ABTS<sup>+·</sup> were revealed on the basis of a rigorous analysis of the DFT calculated data. It was shown that among all the studied food acids, only caffeic acid exhibits a clear-cut significant synergistic effect with glutathione. It established the electronic and structural factors underlying the mechanism of the synergistic interaction of the mixture caffeic acid and glutathione in its reaction with ABTS<sup>+·</sup>. The main causes of this considered synergistic effect are, firstly, the presence of the 3-OH and 4-OH hydroxyl groups in the structure of caffeic acid, secondly, the greater stability of its anion which contains the deprotonated 4-OH hydroxyl group. All other phenolic food acids under study do not possess the given structural particularity and therefore do not show such synergistic effects with glutathione.
基金National Natural Science Foundation of China (10377011)
文摘This article describes the effects of some factors on the tip clearance flow in axial linear turbine cascades. The measurements of the total pressure loss coefficient are made at the cascade outlets by using a five-hole probe at exit Mach numbers of 0.10, 0.14 and 0.19. At each exit Mach number, experiments are performed at the tip clearance heights of 1.0%, 1.5%, 2.0%, 2.5% and 3.0% of the blade height. The effects of the non-uniform tip clearance height of each blade in the pitchwise direction are also studied. The results show that at a given tip clearance height, generally, total pressure loss rises with exit Mach numbers proportionally. At a fixed exit Mach number, the total pressure loss augments nearly proportionally as the tip clearance height increases. The increased tip clearance heights in the tip regions of two adjacent blades are to be blame for the larger clearance loss of the center blade. Compared to the effects of the tip clearance height, the effects of the exit Mach number and the pitchwise variation of the tip clearance height on the cascade total pressure loss are so less significant to be omitted.
