State of research： characteristics, function, and dating of Roman brass tokens Tokens （tesserae） formed part of everyday material culture of both Greeks and Romans.1 Made of wood, bone, clay, or metal, they facilit...State of research： characteristics, function, and dating of Roman brass tokens Tokens （tesserae） formed part of everyday material culture of both Greeks and Romans.1 Made of wood, bone, clay, or metal, they facilitated, for example, entry into the theatre, identification of soldiers, participation in political meetings, or the receipt of a special amount of grain.2展开更多
开展生态脆弱区农户环境经济代谢研究对于乡村精准治理和区域可持续发展具有重要意义。作为我国典型生态脆弱区和北方重要生态安全屏障的辽西北地区,其生态环境质量改善与农牧民生计提升对东北地区乡村振兴至关重要。本文以辽西北地区...开展生态脆弱区农户环境经济代谢研究对于乡村精准治理和区域可持续发展具有重要意义。作为我国典型生态脆弱区和北方重要生态安全屏障的辽西北地区,其生态环境质量改善与农牧民生计提升对东北地区乡村振兴至关重要。本文以辽西北地区风沙危害最严重的彰武县北部7个乡镇为研究区,采用问卷调研与半结构式访谈等方法,基于家庭尺度环境经济代谢框架,对该地区以碳排放和水资源消耗为核心表征的典型农户家庭环境经济代谢活动进行研究。结果表明:辽西北北部地区乡村户均水资源消耗量和用水强度分别为14105 m^(3)和0.14 m^(3)·元^(-1),户均碳排放量和碳强度分别为36.72 t CO_(2)·a^(-1)和0.31 kg CO_(2)·元^(-1),人均碳排放量达9.90 t CO_(2)·a^(-1);以种植、养殖和种养结合为主的家庭水资源消耗量、碳排放量及其强度均存在较大差异,其中,种植主导型家庭水资源消耗量和用水强度均最高,养殖主导型家庭碳排放量最高,而种养结合型碳排放强度最大,但三种类型家庭环境经济代谢特征均表现为“高耗水高碳排”;家庭生计模式不同是造成环境经济代谢水平存在差异的主要原因,其中,养殖主导型家庭单位收入环境经济代谢效率相对较佳。未来应采取更加切实可行的策略加快引导辽西北地区乡村向低碳、绿色、循环的可持续发展模式进行转型,以实现乡村振兴。展开更多
Endoscopic retrograde cholangiopancreatography is considered the gold standard for treating benign and malignant biliary obstructions.However,its use in complex biliary obstructions is limited.Over the past decades,th...Endoscopic retrograde cholangiopancreatography is considered the gold standard for treating benign and malignant biliary obstructions.However,its use in complex biliary obstructions is limited.Over the past decades,therapeutic endosonography(EUS)and emerging technologies such as lumen-apposing metal stents have enabled endoscopic treatment of conditions previously requiring nonendoscopic or surgical approaches.Studies show that EUS-guided choledochoduodenostomy is a reliable alternative to endoscopic retrograde cholangiopancreatography in the treatment of distal malignant biliary obstructions and can be considered a primary drainage modality in centers with adequate expertise.For malignant hilar biliary obstructions,draining at least 50%of viable liver tissue often requires combining different modalities.The treatment strategy in these patients should be individualized,depending on the Bismuth classification,patient physical status,and intended systemic therapy.Due to the lack of evidence,general recommendations cannot be made for EUS-guided hepaticoduodenostomy or combined procedures with transhepatic bridging stents.These novel techniques should be limited to selected palliative cases where conventional methods have failed and conducted within clinical trials to generate evidence before broader application.展开更多
Non-precious metal cobalt-based oxide inevitably dissolves for acid oxygen evolution reaction(OER).Designing an efficient deposition channel for leaching cobalt species is a promising approach.The dissolution-depositi...Non-precious metal cobalt-based oxide inevitably dissolves for acid oxygen evolution reaction(OER).Designing an efficient deposition channel for leaching cobalt species is a promising approach.The dissolution-deposition equilibrium of Co is achieved by doping Mn in the lattice of LaCo_(1-x)Mn_(x)O_(3),prolonging the lifespan in acidic conditions by 14 times.The lattice doping of Mn produces a strain that enhances the adsorption capacity of OH^(-).The self-catalysis of Mn causes the leaching Co to be deposited in the form of CoO_(2),which ensures that the long-term stability of LaCo_(1-x)Mn_(x)O_(3)is 70 h instead of 5 h for LaCoO_(3).Mn doping enhances the deprotonation of^(*)OOH→O_(2)in acidic environments.Notably,the over-potential of optimized LaCo_(1-x)Mn_(x)O_(3)is 345 mV at 10 mA cm^(-2)for acidic OER.This work presents a promising method for developing noble metal-free catalysts that enhance the acidic OER activity and stability.展开更多
Suid is one of the most common taxa among the Pleistocene mammalian fauna in China.However,its phylogenetic taxonomy and evolution are far from clear.The newly recovered suid fossil materials from the Early Pleistocen...Suid is one of the most common taxa among the Pleistocene mammalian fauna in China.However,its phylogenetic taxonomy and evolution are far from clear.The newly recovered suid fossil materials from the Early Pleistocene Shanshenmiaozui site in Nihewan Basin in North China provide new insight into the evolution of its kind in North China.The new materials include partial skulls and mandibles of males,and most of their teeth were preserved in situ.The specimens can be referred to the species Sus lydekkeri,which is the only species of Sus found in North China from the Early Pleistocene.The fossils of the once reported Pleistocene species“Potamochoerus chinhsienensis”should also be provisionally included in the species S.lydekkeri according to its form and size,which at least now excludes it from Potamochoerus.The species S.lydekkeri is very close to the extant species S.scrofa,and even was combined into the latter as a chronological subspecies by some authors,while its larger size,prominent preorbital fossa,backwardly positioned infraorbital foramen,frequently appearing verrucosic type(at least the intermediate type of the male lower canine),and simple crown structures support its validness as an independent species.The Early Pleistocene forms are characterized by a larger size,lower L/W ratio of cheekteeth,both upper and lower M3s having no more than three lobes,and the male lower canine is exclusively of a verrucosic type.Suid fossils are a very good indicator of paleoenvironments and paleoclimate.Both the northern and the southern faunas in China contain suid fossils throughout the Pleistocene Epoch,while the southern fauna has prominently more diversified taxa and more abundant fossil collections;whether that is caused by different origins or by environmental modifications is still not clear.展开更多
Traumatic injuries to the central nervous system(CNS) result in disruption of the intricate network of axons which connect functionally related neurons that are widely distributed throughout the brain and spinal cord....Traumatic injuries to the central nervous system(CNS) result in disruption of the intricate network of axons which connect functionally related neurons that are widely distributed throughout the brain and spinal cord.Under normal conditions,maintenance of this complex system is structurally and functionally supported by astrocytes (ACs)and other glial cells,the processes of which form a framework surrounding neuronal cell bodies,dendrites,axons,and synapses.展开更多
It is shown that time asymmetry is essential for deriving thermodynamic law and arises from the turnover of energy while reducing its information content and driving entropy increase. A dynamically interpreted princip...It is shown that time asymmetry is essential for deriving thermodynamic law and arises from the turnover of energy while reducing its information content and driving entropy increase. A dynamically interpreted principle of least action enables time asymmetry and time flow as a generation of action and redefines useful energy as an information system which implements a form of acting information. This is demonstrated using a basic formula, originally applied for time symmetry/energy conservation considerations, relating time asymmetry (which is conventionally denied but here expressly allowed), to energy behaviour. The results derived then explained that a dynamic energy is driving time asymmetry. It is doing it by decreasing the information content of useful energy, thus generating action and entropy increase, explaining action-time as an information phenomenon. Thermodynamic laws follow directly. The formalism derived readily explains what energy is, why it is conserved (1st law of thermodynamics), why entropy increases (2nd law) and that maximum entropy production within the restraints of the system controls self-organized processes of non-linear irreversible thermodynamics. The general significance of the principle of least action arises from its role of controlling the action generating oriented time of nature. These results contrast with present understanding of time neutrality and clock-time, which are here considered a source of paradoxes, intellectual contradictions and dead-end roads in models explaining nature and the universe.展开更多
文摘State of research： characteristics, function, and dating of Roman brass tokens Tokens （tesserae） formed part of everyday material culture of both Greeks and Romans.1 Made of wood, bone, clay, or metal, they facilitated, for example, entry into the theatre, identification of soldiers, participation in political meetings, or the receipt of a special amount of grain.2
文摘开展生态脆弱区农户环境经济代谢研究对于乡村精准治理和区域可持续发展具有重要意义。作为我国典型生态脆弱区和北方重要生态安全屏障的辽西北地区,其生态环境质量改善与农牧民生计提升对东北地区乡村振兴至关重要。本文以辽西北地区风沙危害最严重的彰武县北部7个乡镇为研究区,采用问卷调研与半结构式访谈等方法,基于家庭尺度环境经济代谢框架,对该地区以碳排放和水资源消耗为核心表征的典型农户家庭环境经济代谢活动进行研究。结果表明:辽西北北部地区乡村户均水资源消耗量和用水强度分别为14105 m^(3)和0.14 m^(3)·元^(-1),户均碳排放量和碳强度分别为36.72 t CO_(2)·a^(-1)和0.31 kg CO_(2)·元^(-1),人均碳排放量达9.90 t CO_(2)·a^(-1);以种植、养殖和种养结合为主的家庭水资源消耗量、碳排放量及其强度均存在较大差异,其中,种植主导型家庭水资源消耗量和用水强度均最高,养殖主导型家庭碳排放量最高,而种养结合型碳排放强度最大,但三种类型家庭环境经济代谢特征均表现为“高耗水高碳排”;家庭生计模式不同是造成环境经济代谢水平存在差异的主要原因,其中,养殖主导型家庭单位收入环境经济代谢效率相对较佳。未来应采取更加切实可行的策略加快引导辽西北地区乡村向低碳、绿色、循环的可持续发展模式进行转型,以实现乡村振兴。
文摘Endoscopic retrograde cholangiopancreatography is considered the gold standard for treating benign and malignant biliary obstructions.However,its use in complex biliary obstructions is limited.Over the past decades,therapeutic endosonography(EUS)and emerging technologies such as lumen-apposing metal stents have enabled endoscopic treatment of conditions previously requiring nonendoscopic or surgical approaches.Studies show that EUS-guided choledochoduodenostomy is a reliable alternative to endoscopic retrograde cholangiopancreatography in the treatment of distal malignant biliary obstructions and can be considered a primary drainage modality in centers with adequate expertise.For malignant hilar biliary obstructions,draining at least 50%of viable liver tissue often requires combining different modalities.The treatment strategy in these patients should be individualized,depending on the Bismuth classification,patient physical status,and intended systemic therapy.Due to the lack of evidence,general recommendations cannot be made for EUS-guided hepaticoduodenostomy or combined procedures with transhepatic bridging stents.These novel techniques should be limited to selected palliative cases where conventional methods have failed and conducted within clinical trials to generate evidence before broader application.
基金financially supported by the Shandong Provincial Natural Science Foundation(ZR2023LFG005)the National Natural Science Foundation of China(Nos.22479161,52274308 and U22B20144)the Fundamental Research Funds for the Central Universities(No.24CX03012A)。
文摘Non-precious metal cobalt-based oxide inevitably dissolves for acid oxygen evolution reaction(OER).Designing an efficient deposition channel for leaching cobalt species is a promising approach.The dissolution-deposition equilibrium of Co is achieved by doping Mn in the lattice of LaCo_(1-x)Mn_(x)O_(3),prolonging the lifespan in acidic conditions by 14 times.The lattice doping of Mn produces a strain that enhances the adsorption capacity of OH^(-).The self-catalysis of Mn causes the leaching Co to be deposited in the form of CoO_(2),which ensures that the long-term stability of LaCo_(1-x)Mn_(x)O_(3)is 70 h instead of 5 h for LaCoO_(3).Mn doping enhances the deprotonation of^(*)OOH→O_(2)in acidic environments.Notably,the over-potential of optimized LaCo_(1-x)Mn_(x)O_(3)is 345 mV at 10 mA cm^(-2)for acidic OER.This work presents a promising method for developing noble metal-free catalysts that enhance the acidic OER activity and stability.
文摘Suid is one of the most common taxa among the Pleistocene mammalian fauna in China.However,its phylogenetic taxonomy and evolution are far from clear.The newly recovered suid fossil materials from the Early Pleistocene Shanshenmiaozui site in Nihewan Basin in North China provide new insight into the evolution of its kind in North China.The new materials include partial skulls and mandibles of males,and most of their teeth were preserved in situ.The specimens can be referred to the species Sus lydekkeri,which is the only species of Sus found in North China from the Early Pleistocene.The fossils of the once reported Pleistocene species“Potamochoerus chinhsienensis”should also be provisionally included in the species S.lydekkeri according to its form and size,which at least now excludes it from Potamochoerus.The species S.lydekkeri is very close to the extant species S.scrofa,and even was combined into the latter as a chronological subspecies by some authors,while its larger size,prominent preorbital fossa,backwardly positioned infraorbital foramen,frequently appearing verrucosic type(at least the intermediate type of the male lower canine),and simple crown structures support its validness as an independent species.The Early Pleistocene forms are characterized by a larger size,lower L/W ratio of cheekteeth,both upper and lower M3s having no more than three lobes,and the male lower canine is exclusively of a verrucosic type.Suid fossils are a very good indicator of paleoenvironments and paleoclimate.Both the northern and the southern faunas in China contain suid fossils throughout the Pleistocene Epoch,while the southern fauna has prominently more diversified taxa and more abundant fossil collections;whether that is caused by different origins or by environmental modifications is still not clear.
文摘Traumatic injuries to the central nervous system(CNS) result in disruption of the intricate network of axons which connect functionally related neurons that are widely distributed throughout the brain and spinal cord.Under normal conditions,maintenance of this complex system is structurally and functionally supported by astrocytes (ACs)and other glial cells,the processes of which form a framework surrounding neuronal cell bodies,dendrites,axons,and synapses.
文摘It is shown that time asymmetry is essential for deriving thermodynamic law and arises from the turnover of energy while reducing its information content and driving entropy increase. A dynamically interpreted principle of least action enables time asymmetry and time flow as a generation of action and redefines useful energy as an information system which implements a form of acting information. This is demonstrated using a basic formula, originally applied for time symmetry/energy conservation considerations, relating time asymmetry (which is conventionally denied but here expressly allowed), to energy behaviour. The results derived then explained that a dynamic energy is driving time asymmetry. It is doing it by decreasing the information content of useful energy, thus generating action and entropy increase, explaining action-time as an information phenomenon. Thermodynamic laws follow directly. The formalism derived readily explains what energy is, why it is conserved (1st law of thermodynamics), why entropy increases (2nd law) and that maximum entropy production within the restraints of the system controls self-organized processes of non-linear irreversible thermodynamics. The general significance of the principle of least action arises from its role of controlling the action generating oriented time of nature. These results contrast with present understanding of time neutrality and clock-time, which are here considered a source of paradoxes, intellectual contradictions and dead-end roads in models explaining nature and the universe.
