An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control...An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control algorithm can update the control law online through real-time data to make the controller adapt to the environment and improve the control precision.Specifically,based on the adaptive backstepping framework,virtual control laws and Lyapunov functions are designed for each subsystem.Three direction interference observers are designed to track the timevarying boundary disturbance.On this basis,the inverse of the dead zone and linear state transformation are used to compensate for the original system and eliminate the adverse effects of the dead zone.In addition,the stability of the closed-loop system is proven by Lyapunov stability theory.All the system states are bounded,and the vibration offset of the riser converges to a small area of the initial position.Finally,four examples of flexible marine risers are simulated in MATLAB to verify the effectiveness of the proposed controller.展开更多
Anode-free solid-state lithium metal batteries(AF-SSLBs)have the potential to deliver higher energy density and improved safety beyond lithium-metal batteries.However,the unclear mechanism for the fast capacity decay ...Anode-free solid-state lithium metal batteries(AF-SSLBs)have the potential to deliver higher energy density and improved safety beyond lithium-metal batteries.However,the unclear mechanism for the fast capacity decay in AF-SSLBs,either determined by dead Li or solid electrolyte interface(SEI),limits the proposal of effective strategies to prolong cycling life.To clarify the underlying mechanism,herein,the evolution of SEI and dead Li is quantitatively analyzed by a solid-state nuclear magnetic resonance(ss-NMR)technology in a typical LiPF6-based polymer electrolyte.The results show that the initial capacity loss is attributed to the formation of SEI,while the dead Li dominates the following capacity loss and the growth rate is 0.141 mA h cm^(−2)cycle−1.To reduce the active Li loss,the combination of inorganic-rich SEI and self-healing electrostatic shield effect is proposed to improve the reversibility of Li deposition/dissolution behavior,which reduces the capacity loss rate for the initial SEI and following dead Li generation by 2.3 and 20.1 folds,respectively.As a result,the initial Coulombic efficiency(ICE)and stable CE increase by 15.1%and 15.3%in Li-Cu cells,which guides the rational design of high-performance AF-SSLBs.展开更多
This article explores the dead universe theory as a novel interpretation for the origin and evolution of the universe, suggesting that our cosmos may have originated from the remnants of a preceding universe. This per...This article explores the dead universe theory as a novel interpretation for the origin and evolution of the universe, suggesting that our cosmos may have originated from the remnants of a preceding universe. This perspective challenges the conventional Big Bang theory, particularly concerning dark matter, the expansion of the universe, and the interpretation of phenomena such as gravitational waves.展开更多
Research Background: The marketing of cosmetic products derived from Dead Sea (DS) mud has undergone significant evolution, transforming from simple souvenirs into a large-scale cosmetic industry offering a diverse ar...Research Background: The marketing of cosmetic products derived from Dead Sea (DS) mud has undergone significant evolution, transforming from simple souvenirs into a large-scale cosmetic industry offering a diverse array of products. DS mud is utilized both as pure mud for home spa treatments and as an active ingredient in cosmetic and cosmeceutical formulations. Its global appeal is largely due to its natural, health-oriented image, which aligns with consumer preferences and provides assurance regarding its use in skincare. Research Objectives: This review examines the published data related to the rationale for formulating DS mud in cosmetics, the biological and cosmetic effects of DS mud on the skin, and the speculated bio-mechanisms underlying these effects. Methods: We screened relevant literature on DS mud collected from the shores of the Dead Sea in Jordan and Israel. Publications on mineral muds excavated in different locations around the globe, as well as studies on the biological mechanisms of other DS minerals, were also reviewed as indications and supportive recommendations. Summarizing the vast collected data into a comprehensive review was undertaken to expose readers to the various aspects of DS mud in cosmetics. Results: The primary reason for formulating DS mud in skincare products is its deep cleansing and skin detoxification properties. Consequently, it is often incorporated into rinse-off masks, soaps, and scrubbing products. Additionally, DS mud is used in leave-on products and sheet masks. Cosmeceutical applications of DS mud, recommended for various skin conditions, offer complementary treatments to improve the quality of life for people with skin diseases. The physicochemical and biological effects of DS mud are driven by its rich mineral ion composition, including magnesium, calcium, sodium, potassium, zinc, and strontium—elements known to improve skin barrier function, enhance hydration, and reduce inflammation. The high salt concentration induces moderate ionic osmotic stress, stimulating cellular growth and hydration pathways. Moreover, DS mud’s anti-microbial properties further contribute to its therapeutic potential. Ongoing innovations in formulation techniques continue to expand the applications of DS mud, including blending it with other active ingredients, developing novel application methods, and refining manufacturing processes to improve product quality and efficacy. Conclusions: DS mud remains a valuable ingredient in modern skincare due to its rich mineral content and therapeutic properties. Ongoing research and technological advancements promise further innovations, reinforcing its status as a natural and effective component in the global cosmetics industry.展开更多
The dead fuel moisture content(DFMC)is the key driver leading to fire occurrence.Accurately estimating the DFMC could help identify locations facing fire risks,prioritise areas for fire monitoring,and facilitate timel...The dead fuel moisture content(DFMC)is the key driver leading to fire occurrence.Accurately estimating the DFMC could help identify locations facing fire risks,prioritise areas for fire monitoring,and facilitate timely deployment of fire-suppression resources.In this study,the DFMC and environmental variables,including air temperature,relative humidity,wind speed,solar radiation,rainfall,atmospheric pressure,soil temperature,and soil humidity,were simultaneously measured in a grassland of Ergun City,Inner Mongolia Autonomous Region of China in 2021.We chose three regression models,i.e.,random forest(RF)model,extreme gradient boosting(XGB)model,and boosted regression tree(BRT)model,to model the seasonal DFMC according to the data collected.To ensure accuracy,we added time-lag variables of 3 d to the models.The results showed that the RF model had the best fitting effect with an R2value of 0.847 and a prediction accuracy with a mean absolute error score of 4.764%among the three models.The accuracies of the models in spring and autumn were higher than those in the other two seasons.In addition,different seasons had different key influencing factors,and the degree of influence of these factors on the DFMC changed with time lags.Moreover,time-lag variables within 44 h clearly improved the fitting effect and prediction accuracy,indicating that environmental conditions within approximately 48 h greatly influence the DFMC.This study highlights the importance of considering 48 h time-lagged variables when predicting the DFMC of grassland fuels and mapping grassland fire risks based on the DFMC to help locate high-priority areas for grassland fire monitoring and prevention.展开更多
[Objectives]This study was conducted to evaluate the nutritional value and safety of black soldier flies fed with dead pig meat and bone meal(DPMBM)and to explore the resource utilization of DPMBM.[Methods]The general...[Objectives]This study was conducted to evaluate the nutritional value and safety of black soldier flies fed with dead pig meat and bone meal(DPMBM)and to explore the resource utilization of DPMBM.[Methods]The general nutrient composition,amino acids,fatty acids and mineral elements of black soldier fly meal(BSLM)were detected and analyzed.[Results]The results showed that the contents of moisture,crude protein,crude fat and ash in BSLM were 3.42%,42.31%,34.04%and 5.40%,respectively.The contents of total amino acids(TAA),essential amino acids(∑EAA)and non-essential amino acids(∑NEAA)and umami amino acids(∑DAA),the EAA/TAA value and the EAA/NEAA value were 37.93%,13.08%,24.85%,13.43%,34.47%,52.61%,respectively.A total of eight kinds of saturated fatty acids and seven kinds of unsaturated fatty acids were detected,accounting for 63.65%and 32.67%of the total fatty acids.Among the major mineral elements,the content of Ca was the highest,followed by K,Mg and Na.Among the trace mineral elements,the content of Mn was the highest,followed by Fe,Zn,Cu,Ni,Cr,Cd,As,Pb,Se,Sn,Ti,Sb and Hg.The contents of heavy metal mineral elements in BSLM were far lower than the limits specified in Hygienical Standard for Feeds.[Conclusions]In conclusion,BSLM has high nutritional value and good safety of heavy metals,and thus great potential for development and utilization as a high quality dietary protein,fat and mineral elements source.展开更多
Chest wall reconstruction is a surgical procedure aimed at restoring the integrity and function of the chest wall, which may be damaged due to trauma, cancer, infection, or congenital defects. The chest wall plays a v...Chest wall reconstruction is a surgical procedure aimed at restoring the integrity and function of the chest wall, which may be damaged due to trauma, cancer, infection, or congenital defects. The chest wall plays a vital role in protecting the thoracic organs, supporting the respiratory system, and maintaining the shape of the chest. Therefore, any defect or deformity of the chest wall can have significant functional and aesthetic consequences for the patient. The authors present a case report at Kenyatta National Hospital (KNH) of a dyspneic 47-year-old male patient with a right anterolateral chest wall defect post-pneumonectomy previously complicated by bronchopleural fistula. Past attempts at the chest wall reconstruction had utilized the ipsilateral latissimus dorsi muscle, pectoralis major muscle, and the omental pedicled flaps with limited success. A chimeric anterolateral thigh (ALT) perforator-free flap with vastus lateralis (VL) muscle was used to obliterate the post-pneumonectomy intrathoracic dead space and to provide a cutaneous paddle. This case report aims to show the versatility of the ALT flap for chest wall reconstruction to prevent the post-pneumonectomy syndrome associated with tracheal deviation, inspiratory stridor, and exertional dyspnea. In conclusion, chest wall reconstruction with obliteration of intrathoracic dead space post-pneumonectomy is challenging and needs careful planning and execution.展开更多
The quantitative trait loci （QTLs） for the dead leaf rate （DLR） and the dead seedling rate （DSR） at the different rice growing periods after transplanting under alkaline stress were identified using an F2：3 pop...The quantitative trait loci （QTLs） for the dead leaf rate （DLR） and the dead seedling rate （DSR） at the different rice growing periods after transplanting under alkaline stress were identified using an F2：3 population, which included 200 individuals and lines derived from a cross between two japonica rice cultivars Gaochan 106 and Changbai 9 with microsatellite markers. The DLR detected at 20 days to 62 days after transplanting under alkaline stress showed continuous normal or near normal distributions in F3 lines, which was the quantitative trait controlled by multiple genes. The DSR showed a continuous distribution with 3 or 4 peaks and was the quantitative trait controlled by main and multiple genes when rice was grown for 62 days after transplanting under alkaline stress. Thirteen QTLs associated with DLR were detected at 20 days to 62 days after transplanting under alkaline stress. Among these, qDLR9-2 located in RM5786-RM160 on chromosome 9 was detected at 34 days, 41 days, 48 days, 55 days, and 62 days, respectively; qDLR4 located in RM3524-RM3866 on chromosome 4 was detected at 34 days, 41 days, and 48 days, respectively; qDLR7-1 located in RM3859-RM320 on chromosome 7 was detected at 20 days and 27 days; and qDLR6-2 in RM1340-RM5957 on chromosome 6 was detected at 55 days and 62 days, respectively. The alleles of both qDLR9-2 and qDLR4 were derived from alkaline sensitive parent ＂Gaochanl06＂. The alleles of both qDLR7-1 and qDLR6-2 were from alkaline tolerant parent Changbai 9. These gene actions showed dominance and over dominance primarily. Six QTLs associated with DSR were detected at 62 days after transplanting under alkaline stress. Among these, qDSR6-2 and qDSR8 were located in RM1340-RM5957 on chromosome 6 and in RM3752-RM404 on chromosome 8, respectively, which were associated with DSR and accounted for 20.32% and 18.86% of the observed phenotypic variation, respectively; qDSR11-2 and qDSR11-3 were located in RM536-RM479 and RM2596-RM286 on chromosome 11, respectively, which were associated with DSR explaining 25.85% and 15.41% of the observed phenotypic variation, respectively. The marker flanking distances of these QTLs were quite far except that of qDSR6-2, which should be researched further.展开更多
基金financially supported by the Sichuan Science and Technology Program(Grant No.2023NSFSC1980)。
文摘An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control algorithm can update the control law online through real-time data to make the controller adapt to the environment and improve the control precision.Specifically,based on the adaptive backstepping framework,virtual control laws and Lyapunov functions are designed for each subsystem.Three direction interference observers are designed to track the timevarying boundary disturbance.On this basis,the inverse of the dead zone and linear state transformation are used to compensate for the original system and eliminate the adverse effects of the dead zone.In addition,the stability of the closed-loop system is proven by Lyapunov stability theory.All the system states are bounded,and the vibration offset of the riser converges to a small area of the initial position.Finally,four examples of flexible marine risers are simulated in MATLAB to verify the effectiveness of the proposed controller.
基金supported by the CAS Project of Young Scientists in Basic Research(YSBR-058)the National Natural Science Foundation of China(22279135)+2 种基金the Outstanding Youth Foundation of Liaoning Province(2023JH3/10200019)the Dalian Science and Technology Innovation Fund(2023JJ11CG004)the Energy Revolution S&T Program of Yulin Innovation Institute of Clean Energy(YIICE E411010316)。
文摘Anode-free solid-state lithium metal batteries(AF-SSLBs)have the potential to deliver higher energy density and improved safety beyond lithium-metal batteries.However,the unclear mechanism for the fast capacity decay in AF-SSLBs,either determined by dead Li or solid electrolyte interface(SEI),limits the proposal of effective strategies to prolong cycling life.To clarify the underlying mechanism,herein,the evolution of SEI and dead Li is quantitatively analyzed by a solid-state nuclear magnetic resonance(ss-NMR)technology in a typical LiPF6-based polymer electrolyte.The results show that the initial capacity loss is attributed to the formation of SEI,while the dead Li dominates the following capacity loss and the growth rate is 0.141 mA h cm^(−2)cycle−1.To reduce the active Li loss,the combination of inorganic-rich SEI and self-healing electrostatic shield effect is proposed to improve the reversibility of Li deposition/dissolution behavior,which reduces the capacity loss rate for the initial SEI and following dead Li generation by 2.3 and 20.1 folds,respectively.As a result,the initial Coulombic efficiency(ICE)and stable CE increase by 15.1%and 15.3%in Li-Cu cells,which guides the rational design of high-performance AF-SSLBs.
文摘This article explores the dead universe theory as a novel interpretation for the origin and evolution of the universe, suggesting that our cosmos may have originated from the remnants of a preceding universe. This perspective challenges the conventional Big Bang theory, particularly concerning dark matter, the expansion of the universe, and the interpretation of phenomena such as gravitational waves.
文摘Research Background: The marketing of cosmetic products derived from Dead Sea (DS) mud has undergone significant evolution, transforming from simple souvenirs into a large-scale cosmetic industry offering a diverse array of products. DS mud is utilized both as pure mud for home spa treatments and as an active ingredient in cosmetic and cosmeceutical formulations. Its global appeal is largely due to its natural, health-oriented image, which aligns with consumer preferences and provides assurance regarding its use in skincare. Research Objectives: This review examines the published data related to the rationale for formulating DS mud in cosmetics, the biological and cosmetic effects of DS mud on the skin, and the speculated bio-mechanisms underlying these effects. Methods: We screened relevant literature on DS mud collected from the shores of the Dead Sea in Jordan and Israel. Publications on mineral muds excavated in different locations around the globe, as well as studies on the biological mechanisms of other DS minerals, were also reviewed as indications and supportive recommendations. Summarizing the vast collected data into a comprehensive review was undertaken to expose readers to the various aspects of DS mud in cosmetics. Results: The primary reason for formulating DS mud in skincare products is its deep cleansing and skin detoxification properties. Consequently, it is often incorporated into rinse-off masks, soaps, and scrubbing products. Additionally, DS mud is used in leave-on products and sheet masks. Cosmeceutical applications of DS mud, recommended for various skin conditions, offer complementary treatments to improve the quality of life for people with skin diseases. The physicochemical and biological effects of DS mud are driven by its rich mineral ion composition, including magnesium, calcium, sodium, potassium, zinc, and strontium—elements known to improve skin barrier function, enhance hydration, and reduce inflammation. The high salt concentration induces moderate ionic osmotic stress, stimulating cellular growth and hydration pathways. Moreover, DS mud’s anti-microbial properties further contribute to its therapeutic potential. Ongoing innovations in formulation techniques continue to expand the applications of DS mud, including blending it with other active ingredients, developing novel application methods, and refining manufacturing processes to improve product quality and efficacy. Conclusions: DS mud remains a valuable ingredient in modern skincare due to its rich mineral content and therapeutic properties. Ongoing research and technological advancements promise further innovations, reinforcing its status as a natural and effective component in the global cosmetics industry.
基金funded by the National Key Research and Development Program of China Strategic International Cooperation in Science and Technology Innovation Program (2018YFE0207800)the National Natural Science Foundation of China (31971483)。
文摘The dead fuel moisture content(DFMC)is the key driver leading to fire occurrence.Accurately estimating the DFMC could help identify locations facing fire risks,prioritise areas for fire monitoring,and facilitate timely deployment of fire-suppression resources.In this study,the DFMC and environmental variables,including air temperature,relative humidity,wind speed,solar radiation,rainfall,atmospheric pressure,soil temperature,and soil humidity,were simultaneously measured in a grassland of Ergun City,Inner Mongolia Autonomous Region of China in 2021.We chose three regression models,i.e.,random forest(RF)model,extreme gradient boosting(XGB)model,and boosted regression tree(BRT)model,to model the seasonal DFMC according to the data collected.To ensure accuracy,we added time-lag variables of 3 d to the models.The results showed that the RF model had the best fitting effect with an R2value of 0.847 and a prediction accuracy with a mean absolute error score of 4.764%among the three models.The accuracies of the models in spring and autumn were higher than those in the other two seasons.In addition,different seasons had different key influencing factors,and the degree of influence of these factors on the DFMC changed with time lags.Moreover,time-lag variables within 44 h clearly improved the fitting effect and prediction accuracy,indicating that environmental conditions within approximately 48 h greatly influence the DFMC.This study highlights the importance of considering 48 h time-lagged variables when predicting the DFMC of grassland fuels and mapping grassland fire risks based on the DFMC to help locate high-priority areas for grassland fire monitoring and prevention.
基金Supported by Modern Agricultural Industry Technology System(CARS-45)Science and Technology Major Project of Hunan Province(2017NK1030).
文摘[Objectives]This study was conducted to evaluate the nutritional value and safety of black soldier flies fed with dead pig meat and bone meal(DPMBM)and to explore the resource utilization of DPMBM.[Methods]The general nutrient composition,amino acids,fatty acids and mineral elements of black soldier fly meal(BSLM)were detected and analyzed.[Results]The results showed that the contents of moisture,crude protein,crude fat and ash in BSLM were 3.42%,42.31%,34.04%and 5.40%,respectively.The contents of total amino acids(TAA),essential amino acids(∑EAA)and non-essential amino acids(∑NEAA)and umami amino acids(∑DAA),the EAA/TAA value and the EAA/NEAA value were 37.93%,13.08%,24.85%,13.43%,34.47%,52.61%,respectively.A total of eight kinds of saturated fatty acids and seven kinds of unsaturated fatty acids were detected,accounting for 63.65%and 32.67%of the total fatty acids.Among the major mineral elements,the content of Ca was the highest,followed by K,Mg and Na.Among the trace mineral elements,the content of Mn was the highest,followed by Fe,Zn,Cu,Ni,Cr,Cd,As,Pb,Se,Sn,Ti,Sb and Hg.The contents of heavy metal mineral elements in BSLM were far lower than the limits specified in Hygienical Standard for Feeds.[Conclusions]In conclusion,BSLM has high nutritional value and good safety of heavy metals,and thus great potential for development and utilization as a high quality dietary protein,fat and mineral elements source.
文摘Chest wall reconstruction is a surgical procedure aimed at restoring the integrity and function of the chest wall, which may be damaged due to trauma, cancer, infection, or congenital defects. The chest wall plays a vital role in protecting the thoracic organs, supporting the respiratory system, and maintaining the shape of the chest. Therefore, any defect or deformity of the chest wall can have significant functional and aesthetic consequences for the patient. The authors present a case report at Kenyatta National Hospital (KNH) of a dyspneic 47-year-old male patient with a right anterolateral chest wall defect post-pneumonectomy previously complicated by bronchopleural fistula. Past attempts at the chest wall reconstruction had utilized the ipsilateral latissimus dorsi muscle, pectoralis major muscle, and the omental pedicled flaps with limited success. A chimeric anterolateral thigh (ALT) perforator-free flap with vastus lateralis (VL) muscle was used to obliterate the post-pneumonectomy intrathoracic dead space and to provide a cutaneous paddle. This case report aims to show the versatility of the ALT flap for chest wall reconstruction to prevent the post-pneumonectomy syndrome associated with tracheal deviation, inspiratory stridor, and exertional dyspnea. In conclusion, chest wall reconstruction with obliteration of intrathoracic dead space post-pneumonectomy is challenging and needs careful planning and execution.
文摘The quantitative trait loci （QTLs） for the dead leaf rate （DLR） and the dead seedling rate （DSR） at the different rice growing periods after transplanting under alkaline stress were identified using an F2：3 population, which included 200 individuals and lines derived from a cross between two japonica rice cultivars Gaochan 106 and Changbai 9 with microsatellite markers. The DLR detected at 20 days to 62 days after transplanting under alkaline stress showed continuous normal or near normal distributions in F3 lines, which was the quantitative trait controlled by multiple genes. The DSR showed a continuous distribution with 3 or 4 peaks and was the quantitative trait controlled by main and multiple genes when rice was grown for 62 days after transplanting under alkaline stress. Thirteen QTLs associated with DLR were detected at 20 days to 62 days after transplanting under alkaline stress. Among these, qDLR9-2 located in RM5786-RM160 on chromosome 9 was detected at 34 days, 41 days, 48 days, 55 days, and 62 days, respectively; qDLR4 located in RM3524-RM3866 on chromosome 4 was detected at 34 days, 41 days, and 48 days, respectively; qDLR7-1 located in RM3859-RM320 on chromosome 7 was detected at 20 days and 27 days; and qDLR6-2 in RM1340-RM5957 on chromosome 6 was detected at 55 days and 62 days, respectively. The alleles of both qDLR9-2 and qDLR4 were derived from alkaline sensitive parent ＂Gaochanl06＂. The alleles of both qDLR7-1 and qDLR6-2 were from alkaline tolerant parent Changbai 9. These gene actions showed dominance and over dominance primarily. Six QTLs associated with DSR were detected at 62 days after transplanting under alkaline stress. Among these, qDSR6-2 and qDSR8 were located in RM1340-RM5957 on chromosome 6 and in RM3752-RM404 on chromosome 8, respectively, which were associated with DSR and accounted for 20.32% and 18.86% of the observed phenotypic variation, respectively; qDSR11-2 and qDSR11-3 were located in RM536-RM479 and RM2596-RM286 on chromosome 11, respectively, which were associated with DSR explaining 25.85% and 15.41% of the observed phenotypic variation, respectively. The marker flanking distances of these QTLs were quite far except that of qDSR6-2, which should be researched further.
