Thyroid-stimulating hormone(TSH)is important for the thyroid gland,development,growth,and metabolism.Defects in TSH production or the thyrotrope cells within the pituitary gland cause congenital hypothyroidism(CH),res...Thyroid-stimulating hormone(TSH)is important for the thyroid gland,development,growth,and metabolism.Defects in TSH production or the thyrotrope cells within the pituitary gland cause congenital hypothyroidism(CH),resulting in growth retardation and neurocognitive impairment.While human TSH is known to display rhythmicity,the molecular mechanisms underlying the circadian regulation of TSH and the effects of TSH-thyroid hormone(TH)signaling on the circadian clock remain elusive.Here we show that TSH,thyroxine(T4),triiodothyronine(T3),and tshba display rhythmicity in both larval and adult zebrafish and tshba is regulated directly by the circadian clock via both E′-box and D-box.Zebrafish tshba^(−/−)mutants manifest congenital hypothyroidism,with the characteristics of low levels of T_(4)and T_(3)and growth retardation.Loss or overexpression of tshba alters the rhythmicity of locomotor activities and expression of core circadian clock genes and hypothalamic-pituitary-thyroid(HPT)axis-related genes.Furthermore,TSH-TH signaling regulates clock2/npas2 via the thyroid response element(TRE)in its promoter,and transcriptome analysis reveals extensive functions of Tshba in zebrafish.Together,our results demonstrate that zebrafish tshba is a direct target of the circadian clock and in turn plays critical roles in circadian regulation along with other functions.展开更多
Many heat transfer tubes are distributed on the tube plates of a steam generator that requires periodic inspection by robots.Existing inspection robots are usually involved in issues:Robots with manipulators need comp...Many heat transfer tubes are distributed on the tube plates of a steam generator that requires periodic inspection by robots.Existing inspection robots are usually involved in issues:Robots with manipulators need complicated installation due to their fixed base;tube mobile robots suffer from low running efficiency because of their structural restricts.Since there are thousands of tubes to be checked,task planning is essential to guarantee the precise,orderly,and efficient inspection process.Most in-service robots check the task tubes using row-by-row and column-bycolumn planning.This leads to unnecessary inspections,resulting in a long shutdown and affecting the regular operation of a nuclear power plant.Therefore,this paper introduces the structure and control system of a dexterous robot and proposes a task planning method.This method proceeds into three steps:task allocation,base position search,and sequence planning.To allocate the task regions,this method calculates the tool work matrix and proposes a criterion to evaluate a sub-region.And then all tasks contained in the sub-region are considered globally to search the base positions.Lastly,we apply an improved ant colony algorithm for base sequence planning and determine the inspection orders according to the planned path.We validated the optimized algorithm by conducting task planning experiments using our robot on a tube sheet.The results show that the proposed method can accomplish full task coverage with few repetitive or redundant inspections and it increases the efficiency by 33.31% compared to the traditional planning algorithms.展开更多
基金supported by grants from the National Key Research and Development Program of China(2019YFA0802400)the National Natural Science Foundation of China(NSFC)(#31300969,#31961133026,#31871187)the Natural Science Foundation of Jiangsu Province(BK20130302),a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PARD).
文摘Thyroid-stimulating hormone(TSH)is important for the thyroid gland,development,growth,and metabolism.Defects in TSH production or the thyrotrope cells within the pituitary gland cause congenital hypothyroidism(CH),resulting in growth retardation and neurocognitive impairment.While human TSH is known to display rhythmicity,the molecular mechanisms underlying the circadian regulation of TSH and the effects of TSH-thyroid hormone(TH)signaling on the circadian clock remain elusive.Here we show that TSH,thyroxine(T4),triiodothyronine(T3),and tshba display rhythmicity in both larval and adult zebrafish and tshba is regulated directly by the circadian clock via both E′-box and D-box.Zebrafish tshba^(−/−)mutants manifest congenital hypothyroidism,with the characteristics of low levels of T_(4)and T_(3)and growth retardation.Loss or overexpression of tshba alters the rhythmicity of locomotor activities and expression of core circadian clock genes and hypothalamic-pituitary-thyroid(HPT)axis-related genes.Furthermore,TSH-TH signaling regulates clock2/npas2 via the thyroid response element(TRE)in its promoter,and transcriptome analysis reveals extensive functions of Tshba in zebrafish.Together,our results demonstrate that zebrafish tshba is a direct target of the circadian clock and in turn plays critical roles in circadian regulation along with other functions.
基金supported by the National Natural Science Foundation of China(Grant No.U2013214)the Self-Planned Task of the State Key Laboratory of Robotics and System(HIT),China(Grant No.SKLRS202001A03).
文摘Many heat transfer tubes are distributed on the tube plates of a steam generator that requires periodic inspection by robots.Existing inspection robots are usually involved in issues:Robots with manipulators need complicated installation due to their fixed base;tube mobile robots suffer from low running efficiency because of their structural restricts.Since there are thousands of tubes to be checked,task planning is essential to guarantee the precise,orderly,and efficient inspection process.Most in-service robots check the task tubes using row-by-row and column-bycolumn planning.This leads to unnecessary inspections,resulting in a long shutdown and affecting the regular operation of a nuclear power plant.Therefore,this paper introduces the structure and control system of a dexterous robot and proposes a task planning method.This method proceeds into three steps:task allocation,base position search,and sequence planning.To allocate the task regions,this method calculates the tool work matrix and proposes a criterion to evaluate a sub-region.And then all tasks contained in the sub-region are considered globally to search the base positions.Lastly,we apply an improved ant colony algorithm for base sequence planning and determine the inspection orders according to the planned path.We validated the optimized algorithm by conducting task planning experiments using our robot on a tube sheet.The results show that the proposed method can accomplish full task coverage with few repetitive or redundant inspections and it increases the efficiency by 33.31% compared to the traditional planning algorithms.