Published proof test coverage(PTC)estimates for emergency shutdown valves(ESDVs)show only moderate agreement and are predominantly opinion-based.A Failure Modes,Effects,and Diagnostics Analysis(FMEDA)was undertaken us...Published proof test coverage(PTC)estimates for emergency shutdown valves(ESDVs)show only moderate agreement and are predominantly opinion-based.A Failure Modes,Effects,and Diagnostics Analysis(FMEDA)was undertaken using component failure rate data to predict PTC for a full stroke test and a partial stroke test.Given the subjective and uncertain aspects of the FMEDA approach,specifically the selection of component failure rates and the determination of the probability of detecting failure modes,a Fuzzy Inference System(FIS)was proposed to manage the data,addressing the inherent uncertainties.Fuzzy inference systems have been used previously for various FMEA type assessments,but this is the first time an FIS has been employed for use with FMEDA.ESDV PTC values were generated from both the standard FMEDA and the fuzzy-FMEDA approaches using data provided by FMEDA experts.This work demonstrates that fuzzy inference systems can address the subjectivity inherent in FMEDA data,enabling reliable estimates of ESDV proof test coverage for both full and partial stroke tests.This facilitates optimized maintenance planning while ensuring safety is not compromised.展开更多
Adsorption of silver ions from aqueous solution onto H2TiO3 was studied. Equilibrium experimental studies were performed to determine the adsorption capacity of H2TiO3 for silver ion at various pH values. Batch experi...Adsorption of silver ions from aqueous solution onto H2TiO3 was studied. Equilibrium experimental studies were performed to determine the adsorption capacity of H2TiO3 for silver ion at various pH values. Batch experiments were conducted in the range of pH value 3?7 and silver ions concentration 10?200 mg/L. The results show that the adsorption is strongly dependent on pH value. The equilibrium absorption capacity of H2TiO3 increases significantly with the increase of pH value from 3 to 7. The adsorption of silver ion obeys the Langmuir isothermal equation well in the concentration range studied, the adsorption constant is 0.054 7, 0.052 4, 0.088 1 at pH 5, 6 and 7, respectively, and the maximum adsorption capacities are 23.64, 29.76 and 40.82 mg/g.展开更多
The silver-doped titania antibacterial agent was synthesized by mixing silver nitrate and the precursor of titania. Effects of thermal treatment on the properties of the silver-doped titania powders were investigated ...The silver-doped titania antibacterial agent was synthesized by mixing silver nitrate and the precursor of titania. Effects of thermal treatment on the properties of the silver-doped titania powders were investigated by thermal gravimeter/differential thermal analyzer(TG/DTA), scanning electron microscope(SEM), and X-ray diffractometer(XRD), respectively. The results show that the anatase phase forms in titania when the powder is calcined at 400 ℃. With the increase of the calcination temperature from 400 to 700 ℃ , the grains of titania agglomerate and the particle size increases from 14 to 23 nm, and the specific surface area decreases from 63 to 38m2g. As the powder is calcined at 700 ℃, titania starts to transform from anatase to rutile phase. The release rate of silver ion of powder treated at the relatively low temperature is larger than that of powder treated at the relatively high temperature. The antibacterial tests show that the antibacterial activity of silver-doped titania powders is excellent against E.coli and S. aureus, and the antibacterial activity of powders weakens with the increase of the calcination temperature.展开更多
HWANG Jenq-Neng received his Ph.D. degree from the University of Southern California, USA. In the summer of 1989, Dr. HWANG joined the De- partment of Electrical Engineering of the Universi- ty of Washington in Seattl...HWANG Jenq-Neng received his Ph.D. degree from the University of Southern California, USA. In the summer of 1989, Dr. HWANG joined the De- partment of Electrical Engineering of the Universi- ty of Washington in Seattle, USA, where he has been promoted to Full Professor since 1999. He served as the Associate Chair for Research fi＇om 2003 to 2005, and from 2011-2015. He is current- ly the Associate Chair for Global Affairs and Inter- national Development in the EE Depamnent. Hehas written more than 330 journal papers, conference papers and book chapters in the areas of machine learning, muhimedia signal processing, and muhimedia system integration and networking, including an au- thored textbook on ＂Multimedia Networking： from Theory to Practice,＂ published by Cambridge University Press. Dr. HWANG has close work- ing relationship with the industry on muhimedia signal processing and nmltimedia networking.展开更多
The coagulase-negative staphylococci (CoNS) have long been considered to be low pathogenicity. The possibility of a horizontal transfer of resistance and virulence genes from S. aureus to CoNS could increase the patho...The coagulase-negative staphylococci (CoNS) have long been considered to be low pathogenicity. The possibility of a horizontal transfer of resistance and virulence genes from S. aureus to CoNS could increase the pathogenicity of these bacteria. The objective of this work is to contribute to a better knowledge of the pathogenicity of (CoNS) strains isolated from surfaces and medico-technical materials of the University Hospital of Abomey-Calavi/Sô-Ava. Seventy strains of CoNS isolated from surfaces and medico-technical materials of the University Hospital of Abomey-Calavi were tested for methicillin resistance. The resistance to methicillin was evaluated phenotypically by the resistance of the strains to cefoxitin and then confirmed by the search for the mecA gene using PCR. The genes encoding staphylococcal chromosomal cassette (SCCmec) types I, II and III originally found in S. aureus were tested in CoNS by multiplex PCR using specific primers. All the strains studied showed resistance to methicillin. However, only 28.5% (20/70) carried the mecA gene. SCCmec was identified in only 17.14% (12/70) of these strains. Four strains carried mecA gene as well as one of the three types of SCCmec searched. SCCmec types I, II and III were identified in CoNS strains studied. SCCmec type I was the most frequent chromosomal cassette in mecA<sup>+</sup> strains, only or in association with another SCCmec. The study also revealed methicillin-resistant strains carrying SCCmec lacking the mecA gene. Finally, 60% (12/20) of the strains were found to be non-typeable. Our results show that CoNS strains present a high resistance to methicillin and the source of this resistance in the CoNS of our study is not only the mecA gene. There is also a high diversity of SCCmec, justified by a large number of non-typeable CoNS strains. The mecA<sup>−</sup> SCCmec<sup>+</sup> methicillin-resistant strains deserve to be sequenced for further studies.展开更多
Background: COVID-19, an infectious viral disease, has caused a global health crisis. Most cases remain asymptomatic. The majority of patients have mild symptoms while about 15% develop a severe form. The clinical spe...Background: COVID-19, an infectious viral disease, has caused a global health crisis. Most cases remain asymptomatic. The majority of patients have mild symptoms while about 15% develop a severe form. The clinical spectrum of SARS-CoV-2 infection appears broad, encompassing asymptomatic infection, upper respiratory tract symptoms, and severe viral pneumonia with respiratory failure that can lead to death. Laboratory tests play an important role in the management of COVID-19 patients. In addition to being essential for the diagnosis, several biological analyses make it possible to identify the inflammatory processes and the potential complications of this disease. This study attempted to identify biochemical assays that could help in the prognosis of the disease to ensure early management. Methods: This was a descriptive study. It focused on patients hospitalized for COVID-19 from March 19, 2020, to January 26, 2021, at the Infectious Disease Management Centre in Lomé (Togo). Medians were compared using the (Mann-Whitney and Wilcoxon) test and frequencies were compared using the Chi-square test or Fisher’s exact test. Results: We included 782 patients. The median age was 41 years IQR from 32 to 55. We observed several biochemical abnormalities in varying proportions for all biochemical parameters studied. Compared to non-serious patients, critically ill patients at admission had more frequently elevated urea, creatinine, transaminases, TG, GGT, CRP and blood glucose. Also, they had more frequent decreases in total cholesterol, HDL-c, blood chloride, and blood calcium. As for patients who died during hospitalization, compared with healed patients, they had more frequent elevations of urea, creatinine, AST, ALT, GGT. CRP and blood glucose. They also had a more frequent decrease in total cholesterol, HDL-c, blood chloride, blood calcium, and blood glucose (p = 0.025). Conclusion: This study shows that COVID-19 is a multi-organ systemic inflammatory viral disease that should be systematically investigated once the diagnosis is confirmed.展开更多
Background:Epidemiological studies have confirmed that longer exposure to insecticides like cypermethrin(CYP)significantly increases the risk of male reproductive toxicity.Crocus sativus L.has been recognized due to i...Background:Epidemiological studies have confirmed that longer exposure to insecticides like cypermethrin(CYP)significantly increases the risk of male reproductive toxicity.Crocus sativus L.has been recognized due to its therapeutic properties,but its exact role and molecular mechanisms in treatment of reproductive dysfunction remain unclear.Methods:During this study,36 rats were randomly divided into six groups(n=6):control,CYP-induced(60 mg/kg),standard(leuprolide 3 mg/kg)and three treatment groups receiving aqueous,ethanolic,and oil extracts(50 mg/kg or 20 mL/kg)for post-toxicity induction.Results:The finding represented that exposure of CYP significantly increased oxidative stress,disrupted testicular architecture,and markedly reduced testosterone levels(P<0.05).Importantly,Crocus sativus L.treatment alleviated these changes by increasing the expression of Nrf2(nuclear factor erythroid 2-related factor 2),restoring the activity of antioxidant enzymes,and enhancing testicular histomorphology.Surprisingly,molecular docking established a high binding affinity of Crocus sativus L.phytoconstituents such as gallic acid,cinnamic acid and quercetin to the Nrf2-Keap1 complex.It is worth noting that,Crocus sativus L.exhibited a high level of protection against reproductive toxicity caused by CYP in male rats,which was mediated by the activation of Nrf2 pathway,reduction of oxidative damage,and favorable ADMET characteristics.Conclusion:Notably,this research provides a more valid,safe,and effective method of developing new drugs for reproductive disorders,however,further investigation is needed to support the research findings and implement it in clinical practice.展开更多
Dear Editor, The tropical plant Madagascar periwinkle Catharanthus roseus （L.） G.Don is a rich source of plant-derived medicinal ter-penoid indole alkaloids （TIAs）, including the anti-hypertensive ajmalicine, the...Dear Editor, The tropical plant Madagascar periwinkle Catharanthus roseus （L.） G.Don is a rich source of plant-derived medicinal ter-penoid indole alkaloids （TIAs）, including the anti-hypertensive ajmalicine, the sedative compound serpentine, and the anti-cancer drugs vinblastine and vincristine. However, the latter two compounds are produced in C. roseus plants only in very low amounts. Elicitors such as hormones （e.g. jasmonates or salicylic acid） activate plant natural defense responses, includ-ing increased secondary metabolite production （EI-Sayed and Verpoorte, 2007; Lackman et al.. 2011）.展开更多
This paper explores the evolution of geoscientific inquiry,tracing the progression from traditional physics-based models to modern data-driven approaches facilitated by significant advancements in artificial intellige...This paper explores the evolution of geoscientific inquiry,tracing the progression from traditional physics-based models to modern data-driven approaches facilitated by significant advancements in artificial intelligence(AI)and data collection techniques.Traditional models,which are grounded in physical and numerical frameworks,provide robust explanations by explicitly reconstructing underlying physical processes.However,their limitations in comprehensively capturing Earth’s complexities and uncertainties pose challenges in optimization and real-world applicability.In contrast,contemporary data-driven models,particularly those utilizing machine learning(ML)and deep learning(DL),leverage extensive geoscience data to glean insights without requiring exhaustive theoretical knowledge.ML techniques have shown promise in addressing Earth science-related questions.Nevertheless,challenges such as data scarcity,computational demands,data privacy concerns,and the“black-box”nature of AI models hinder their seamless integration into geoscience.The integration of physics-based and data-driven methodologies into hybrid models presents an alternative paradigm.These models,which incorporate domain knowledge to guide AI methodologies,demonstrate enhanced efficiency and performance with reduced training data requirements.This review provides a comprehensive overview of geoscientific research paradigms,emphasizing untapped opportunities at the intersection of advanced AI techniques and geoscience.It examines major methodologies,showcases advances in large-scale models,and discusses the challenges and prospects that will shape the future landscape of AI in geoscience.The paper outlines a dynamic field ripe with possibilities,poised to unlock new understandings of Earth’s complexities and further advance geoscience exploration.展开更多
文摘Published proof test coverage(PTC)estimates for emergency shutdown valves(ESDVs)show only moderate agreement and are predominantly opinion-based.A Failure Modes,Effects,and Diagnostics Analysis(FMEDA)was undertaken using component failure rate data to predict PTC for a full stroke test and a partial stroke test.Given the subjective and uncertain aspects of the FMEDA approach,specifically the selection of component failure rates and the determination of the probability of detecting failure modes,a Fuzzy Inference System(FIS)was proposed to manage the data,addressing the inherent uncertainties.Fuzzy inference systems have been used previously for various FMEA type assessments,but this is the first time an FIS has been employed for use with FMEDA.ESDV PTC values were generated from both the standard FMEDA and the fuzzy-FMEDA approaches using data provided by FMEDA experts.This work demonstrates that fuzzy inference systems can address the subjectivity inherent in FMEDA data,enabling reliable estimates of ESDV proof test coverage for both full and partial stroke tests.This facilitates optimized maintenance planning while ensuring safety is not compromised.
基金Project(04GK2007) supported by the Key Project of Scientific and Technological Department of Hunan Province, China
文摘Adsorption of silver ions from aqueous solution onto H2TiO3 was studied. Equilibrium experimental studies were performed to determine the adsorption capacity of H2TiO3 for silver ion at various pH values. Batch experiments were conducted in the range of pH value 3?7 and silver ions concentration 10?200 mg/L. The results show that the adsorption is strongly dependent on pH value. The equilibrium absorption capacity of H2TiO3 increases significantly with the increase of pH value from 3 to 7. The adsorption of silver ion obeys the Langmuir isothermal equation well in the concentration range studied, the adsorption constant is 0.054 7, 0.052 4, 0.088 1 at pH 5, 6 and 7, respectively, and the maximum adsorption capacities are 23.64, 29.76 and 40.82 mg/g.
基金Project(04GK2007) supported by the Key Project of Scientific and Technological Department of Human Province, China
文摘The silver-doped titania antibacterial agent was synthesized by mixing silver nitrate and the precursor of titania. Effects of thermal treatment on the properties of the silver-doped titania powders were investigated by thermal gravimeter/differential thermal analyzer(TG/DTA), scanning electron microscope(SEM), and X-ray diffractometer(XRD), respectively. The results show that the anatase phase forms in titania when the powder is calcined at 400 ℃. With the increase of the calcination temperature from 400 to 700 ℃ , the grains of titania agglomerate and the particle size increases from 14 to 23 nm, and the specific surface area decreases from 63 to 38m2g. As the powder is calcined at 700 ℃, titania starts to transform from anatase to rutile phase. The release rate of silver ion of powder treated at the relatively low temperature is larger than that of powder treated at the relatively high temperature. The antibacterial tests show that the antibacterial activity of silver-doped titania powders is excellent against E.coli and S. aureus, and the antibacterial activity of powders weakens with the increase of the calcination temperature.
文摘HWANG Jenq-Neng received his Ph.D. degree from the University of Southern California, USA. In the summer of 1989, Dr. HWANG joined the De- partment of Electrical Engineering of the Universi- ty of Washington in Seattle, USA, where he has been promoted to Full Professor since 1999. He served as the Associate Chair for Research fi＇om 2003 to 2005, and from 2011-2015. He is current- ly the Associate Chair for Global Affairs and Inter- national Development in the EE Depamnent. Hehas written more than 330 journal papers, conference papers and book chapters in the areas of machine learning, muhimedia signal processing, and muhimedia system integration and networking, including an au- thored textbook on ＂Multimedia Networking： from Theory to Practice,＂ published by Cambridge University Press. Dr. HWANG has close work- ing relationship with the industry on muhimedia signal processing and nmltimedia networking.
文摘The coagulase-negative staphylococci (CoNS) have long been considered to be low pathogenicity. The possibility of a horizontal transfer of resistance and virulence genes from S. aureus to CoNS could increase the pathogenicity of these bacteria. The objective of this work is to contribute to a better knowledge of the pathogenicity of (CoNS) strains isolated from surfaces and medico-technical materials of the University Hospital of Abomey-Calavi/Sô-Ava. Seventy strains of CoNS isolated from surfaces and medico-technical materials of the University Hospital of Abomey-Calavi were tested for methicillin resistance. The resistance to methicillin was evaluated phenotypically by the resistance of the strains to cefoxitin and then confirmed by the search for the mecA gene using PCR. The genes encoding staphylococcal chromosomal cassette (SCCmec) types I, II and III originally found in S. aureus were tested in CoNS by multiplex PCR using specific primers. All the strains studied showed resistance to methicillin. However, only 28.5% (20/70) carried the mecA gene. SCCmec was identified in only 17.14% (12/70) of these strains. Four strains carried mecA gene as well as one of the three types of SCCmec searched. SCCmec types I, II and III were identified in CoNS strains studied. SCCmec type I was the most frequent chromosomal cassette in mecA<sup>+</sup> strains, only or in association with another SCCmec. The study also revealed methicillin-resistant strains carrying SCCmec lacking the mecA gene. Finally, 60% (12/20) of the strains were found to be non-typeable. Our results show that CoNS strains present a high resistance to methicillin and the source of this resistance in the CoNS of our study is not only the mecA gene. There is also a high diversity of SCCmec, justified by a large number of non-typeable CoNS strains. The mecA<sup>−</sup> SCCmec<sup>+</sup> methicillin-resistant strains deserve to be sequenced for further studies.
文摘Background: COVID-19, an infectious viral disease, has caused a global health crisis. Most cases remain asymptomatic. The majority of patients have mild symptoms while about 15% develop a severe form. The clinical spectrum of SARS-CoV-2 infection appears broad, encompassing asymptomatic infection, upper respiratory tract symptoms, and severe viral pneumonia with respiratory failure that can lead to death. Laboratory tests play an important role in the management of COVID-19 patients. In addition to being essential for the diagnosis, several biological analyses make it possible to identify the inflammatory processes and the potential complications of this disease. This study attempted to identify biochemical assays that could help in the prognosis of the disease to ensure early management. Methods: This was a descriptive study. It focused on patients hospitalized for COVID-19 from March 19, 2020, to January 26, 2021, at the Infectious Disease Management Centre in Lomé (Togo). Medians were compared using the (Mann-Whitney and Wilcoxon) test and frequencies were compared using the Chi-square test or Fisher’s exact test. Results: We included 782 patients. The median age was 41 years IQR from 32 to 55. We observed several biochemical abnormalities in varying proportions for all biochemical parameters studied. Compared to non-serious patients, critically ill patients at admission had more frequently elevated urea, creatinine, transaminases, TG, GGT, CRP and blood glucose. Also, they had more frequent decreases in total cholesterol, HDL-c, blood chloride, and blood calcium. As for patients who died during hospitalization, compared with healed patients, they had more frequent elevations of urea, creatinine, AST, ALT, GGT. CRP and blood glucose. They also had a more frequent decrease in total cholesterol, HDL-c, blood chloride, blood calcium, and blood glucose (p = 0.025). Conclusion: This study shows that COVID-19 is a multi-organ systemic inflammatory viral disease that should be systematically investigated once the diagnosis is confirmed.
文摘Background:Epidemiological studies have confirmed that longer exposure to insecticides like cypermethrin(CYP)significantly increases the risk of male reproductive toxicity.Crocus sativus L.has been recognized due to its therapeutic properties,but its exact role and molecular mechanisms in treatment of reproductive dysfunction remain unclear.Methods:During this study,36 rats were randomly divided into six groups(n=6):control,CYP-induced(60 mg/kg),standard(leuprolide 3 mg/kg)and three treatment groups receiving aqueous,ethanolic,and oil extracts(50 mg/kg or 20 mL/kg)for post-toxicity induction.Results:The finding represented that exposure of CYP significantly increased oxidative stress,disrupted testicular architecture,and markedly reduced testosterone levels(P<0.05).Importantly,Crocus sativus L.treatment alleviated these changes by increasing the expression of Nrf2(nuclear factor erythroid 2-related factor 2),restoring the activity of antioxidant enzymes,and enhancing testicular histomorphology.Surprisingly,molecular docking established a high binding affinity of Crocus sativus L.phytoconstituents such as gallic acid,cinnamic acid and quercetin to the Nrf2-Keap1 complex.It is worth noting that,Crocus sativus L.exhibited a high level of protection against reproductive toxicity caused by CYP in male rats,which was mediated by the activation of Nrf2 pathway,reduction of oxidative damage,and favorable ADMET characteristics.Conclusion:Notably,this research provides a more valid,safe,and effective method of developing new drugs for reproductive disorders,however,further investigation is needed to support the research findings and implement it in clinical practice.
文摘Dear Editor, The tropical plant Madagascar periwinkle Catharanthus roseus （L.） G.Don is a rich source of plant-derived medicinal ter-penoid indole alkaloids （TIAs）, including the anti-hypertensive ajmalicine, the sedative compound serpentine, and the anti-cancer drugs vinblastine and vincristine. However, the latter two compounds are produced in C. roseus plants only in very low amounts. Elicitors such as hormones （e.g. jasmonates or salicylic acid） activate plant natural defense responses, includ-ing increased secondary metabolite production （EI-Sayed and Verpoorte, 2007; Lackman et al.. 2011）.
基金supported by National Natural Science Foundation of China(T2225019,41925007,62372470,U21A2013,42201415,42022054,42241109,42077156,52121006,42090014,and 42325107)the National Key R&D Programme of China(2022YFF0500)+2 种基金the Youth Innovation Promotion Association CAS(2023112)the Strategic Priority Research Program of CAS(XDA23090303)the RECLAIM Network Plus(EP/W034034/1).
文摘This paper explores the evolution of geoscientific inquiry,tracing the progression from traditional physics-based models to modern data-driven approaches facilitated by significant advancements in artificial intelligence(AI)and data collection techniques.Traditional models,which are grounded in physical and numerical frameworks,provide robust explanations by explicitly reconstructing underlying physical processes.However,their limitations in comprehensively capturing Earth’s complexities and uncertainties pose challenges in optimization and real-world applicability.In contrast,contemporary data-driven models,particularly those utilizing machine learning(ML)and deep learning(DL),leverage extensive geoscience data to glean insights without requiring exhaustive theoretical knowledge.ML techniques have shown promise in addressing Earth science-related questions.Nevertheless,challenges such as data scarcity,computational demands,data privacy concerns,and the“black-box”nature of AI models hinder their seamless integration into geoscience.The integration of physics-based and data-driven methodologies into hybrid models presents an alternative paradigm.These models,which incorporate domain knowledge to guide AI methodologies,demonstrate enhanced efficiency and performance with reduced training data requirements.This review provides a comprehensive overview of geoscientific research paradigms,emphasizing untapped opportunities at the intersection of advanced AI techniques and geoscience.It examines major methodologies,showcases advances in large-scale models,and discusses the challenges and prospects that will shape the future landscape of AI in geoscience.The paper outlines a dynamic field ripe with possibilities,poised to unlock new understandings of Earth’s complexities and further advance geoscience exploration.
