The urban grass-roots library is an important part of the public cultural service system,and also a place to carry out national reading and lifelong learning,which is of great significance to the construction of a lea...The urban grass-roots library is an important part of the public cultural service system,and also a place to carry out national reading and lifelong learning,which is of great significance to the construction of a learning society.In this paper,the development and evolution of urban grassroots libraries in China are reviewed,and the current situation and usage issues of grassroots libraries in Beijing are analyzed.Moreover,the development strategy of idea stores in London,UK is studied,and characteristics are summarized,and possible references are sought.In the new era,urban grassroots libraries should integrate into communities with multiple functions and play a more sufficient role in public education,learning and training,and other aspects.展开更多
BACKGROUND: Most of the currently available information on purinergic receptors (P2Rs) involved in pain transmission is based on results obtained in dorsal root ganglion or the spinal cord. However, the mechanism o...BACKGROUND: Most of the currently available information on purinergic receptors (P2Rs) involved in pain transmission is based on results obtained in dorsal root ganglion or the spinal cord. However, the mechanism of P2Rs in trigeminal neuralgia remains unclear. OBJECTIVE: To investigate changes in the P2R-mediated calcium signaling pathway in nociceptive trigemJnal ganglion neurons. DESIGN, TIME AND SETTING: In vitro experiments were conducted at the Patch-Clamp Laboratory of Comprehensive Experiment Center of Anhui Medical University, China from September 2008 to June 2009. MATERIALS: Thapsigargin, caffeine, suramin, and adenosine 5'-triphosphate were purchased from Sigma, USA. METHODS: Using Fura-2-based microfluorimetry, intracellular calcium concentration ([Ca^2+]i) was measured in freshly isolated adult rat small trigeminal ganglion neurons before and after drug application. MAIN OUTCOME MEASURES: Fluorescent intensities were expressed as the ratio F340/F380 to observe [Ca^2+]i changes. RESULTS: In normal extracellular solution and Ca^2+-free solution, application of thapsigargin (1 μmol/L), a sarcoplasmic reticulum Ca^2+ pump adenosine 5'-triphosphate inhibitor, as well as caffeine (20 mmol/L), a ryanodine receptor agonist, triggered [Ca^2+]i increase in small trigeminal ganglion neurons. A similar response was induced by application of adenosine 5'-triphosphate (100 μmol/L). In Ca^2+-free conditions, adenosine 5'-triphosphate-induced [Ca^2+]i transients in small trigeminal ganglion neurons were inhibited in cells pre-treated with thapsigargin (P 〈 0.01), but not by caffeine (P 〉 0.05). In normal, extracellular solution, adenosine 5'-triphosphate-induced [Ca^2+]i transients in small trigeminal ganglion neurons were partly inhibited in cells pre-treated with thapsigargin (P 〈 0.05). CONCLUSION: Inositol-1,4, 5-triphosphate (IP3)- and ryanodine-sensitive Ca^2+ stores exist in rat nociceptive trigeminal ganglion neurons. Two pathways are involved in the purinoreceptor-mediated [Ca^2+]i rise observed in nociceptive trigeminal ganglion neurons. One pathway involves the metabotropic P2Y receptors, which are associated with the IP3 sensitive Ca^2+store, and the second pathway is coupled to ionotropic P2X receptors that induce the Ca^2+ influx.展开更多
In this paper, the optimization of micro-cogeneration (μ-CHP) system sizing for convenience stores in Thailand is conducted under the present condition of fuel prices and tariff rates. The assessment of (μ-CHP) syst...In this paper, the optimization of micro-cogeneration (μ-CHP) system sizing for convenience stores in Thailand is conducted under the present condition of fuel prices and tariff rates. The assessment of (μ-CHP) system performance is analyzed by using Primary Energy Saving (PES) Ratio for evaluating the energy performance. Also, the Annual Cost Saving Ratio (CSR) and Payback Period (PBP) are used for evaluating the economic performance of μ-CHP system. The analysis results show the optimal size of μ-CHP system under possible conditions including the operating schedule and system’s efficiency were conducted.展开更多
Alzheimer’s disease(AD)is the most common form of dementia representing a major problem for public health.In 2017 there were an estimated 50 million patients worldwide and this number is expected to almost double e...Alzheimer’s disease(AD)is the most common form of dementia representing a major problem for public health.In 2017 there were an estimated 50 million patients worldwide and this number is expected to almost double every 20years,reaching 75 million in 2030 and 131.5 million in 2050(https://www.alz.co.uk/research/statistics).展开更多
Pop-up stores present many advantages to brands and customers.They take advantage of seasonality and events and manifest themselves in a relevant way in front of the targeted customer.Following a mixed-method approach...Pop-up stores present many advantages to brands and customers.They take advantage of seasonality and events and manifest themselves in a relevant way in front of the targeted customer.Following a mixed-method approach,semi-structured interview outcomes were used to enrich the proposed research model,which was then tested by a questionnaire.Our research’s results highlighted interesting components respective to the Lebanese market’s pop-up stores;test and experimentation,collection presentation,communication and buzz creation.Test results showed that Lebanese pop-up store atmospheres are characterized by their social dimension;customers are less affected by the aesthetics and more affected by the crowd who frequents the pop-up.Results showed that customers feel happier and are more likely to stay and to spend time in the store than to make purchases.展开更多
According to the reports by World Wide Web,the potential coffee consumer base has a population of 200-250 million in China with huge consumption potential,equals to the total US population.Consumption is limited at th...According to the reports by World Wide Web,the potential coffee consumer base has a population of 200-250 million in China with huge consumption potential,equals to the total US population.Consumption is limited at the current stage,but it is growing rapidly.China is expected to consume over 300,000 tons of coffee bean by 2020 with an average per capita consumption of 200 grams on a yearly basis.展开更多
In 2019,there were 239 brick-and-mortar bookstores in Beijing receiving the support funds,including 85 characteristic bookstores,10 most beautiful bookstores and 2 most influential bookstores,with the total support fu...In 2019,there were 239 brick-and-mortar bookstores in Beijing receiving the support funds,including 85 characteristic bookstores,10 most beautiful bookstores and 2 most influential bookstores,with the total support fund amounting to nearly RMB 100 million.展开更多
The tail latency of end-user requests,which directly impacts the user experience and the revenue,is highly related to its corresponding numerous accesses in key-value stores.The replica selection algorithm is crucial ...The tail latency of end-user requests,which directly impacts the user experience and the revenue,is highly related to its corresponding numerous accesses in key-value stores.The replica selection algorithm is crucial to cut the tail latency of these key-value accesses.Recently,the C3 algorithm,which creatively piggybacks the queue-size of waiting keys from replica servers for the replica selection at clients,is proposed in NSDI 2015.Although C3 improves the tail latency a lot,it suffers from the timeliness issue on the feedback information,which directly influences the replica selection.In this paper,we analysis the evaluation of queuesize of waiting keys of C3,and some findings of queue-size variation were made.It motivate us to propose the Prediction-Based Replica Selection(PRS)algorithm,which predicts the queue-size at replica servers under the poor timeliness condition,instead of utilizing the exponentially weighted moving average of the state piggybacked queue-size as in C3.Consequently,PRS can obtain more accurate queue-size at clients than C3,and thus outperforms C3 in terms of cutting the tail latency.Simulation results confirm the advantage of PRS over C3.展开更多
In 2018,cosmetics stores no longer complained about the difficulty in doing business.Instead,it has been found that a fewer number of stores stuck to their business.Adopting the supermarket model for CS has just compl...In 2018,cosmetics stores no longer complained about the difficulty in doing business.Instead,it has been found that a fewer number of stores stuck to their business.Adopting the supermarket model for CS has just completed the function of commodity transfer.Therefore,the value of this channel has already been cannibalized by e-commerce.But the value of CS is not only reflected in commodity transfer but information transfer and service experience.If we look at the well-performed CS right now,they are either stores selling special goods or stores offering special service for shoppers to experience.展开更多
“It’s horrible!How come the customer satisfaction(CS)channel is such a dismal failure?”Many complained to me.“Destined”,I responded.A.S.Watson Group(Hong Kong)Ltd.saw a significant increase in the number of physi...“It’s horrible!How come the customer satisfaction(CS)channel is such a dismal failure?”Many complained to me.“Destined”,I responded.A.S.Watson Group(Hong Kong)Ltd.saw a significant increase in the number of physical stores to 1,000 in 2011,a benchmark for its domestic counterparts.展开更多
Joseph Abboud, an apparel company from the USA, has announced plans to open its first store in China in autumn of 2008 and will open 15 stores across the country before the end of the year.
This study attempted to examine the importance of storeenvironment in affecting consumers’store choice deci-sion;the relative importance among the three environ-mental factors;and consumers’expectations on store en-...This study attempted to examine the importance of storeenvironment in affecting consumers’store choice deci-sion;the relative importance among the three environ-mental factors;and consumers’expectations on store en-vironment for the casual-wear chain stores in HongKong.Julie Baker’s Three-category framework onstore environments namely ambient,design and socialfactors was adopted for investigation.The results indi-cated that the store environment was important in affect-ing consumers’selection of store for shopping.It alsorevealed that social factor was perceived relatively im-portant than ambient and design factors.Nine store ex-pectation dimensions were categorised and the resultdemonstrated that most respondents were concerned onthe social aspect in their expectation of having a satisfy-ing store environment.展开更多
Developing ocean carbon sinks and improving the marine capacity to capture and store carbon dioxide is an important way to achieve carbon peaking and neutrality.THE ocean plays a vital role in regulating the global cl...Developing ocean carbon sinks and improving the marine capacity to capture and store carbon dioxide is an important way to achieve carbon peaking and neutrality.THE ocean plays a vital role in regulating the global climate.It absorbs the carbon dioxide in the atmosphere and stores it through physical,chemical,and biological processes.The ocean surface dissolves about one third of the carbon dioxide released due to human activities into the atmosphere.展开更多
On 13 March,the US House of Representatives passed a bill targeting short video application TikTok,requiring its Chinese owner ByteDance to divest control of the app;otherwise,the app will be removed from app stores.I...On 13 March,the US House of Representatives passed a bill targeting short video application TikTok,requiring its Chinese owner ByteDance to divest control of the app;otherwise,the app will be removed from app stores.It is another case of the US targeting Chinese tech companies in the name of national security,as was the case with Chinese tech giant Huawei.展开更多
Cells utilize calcium ions(Ca^2+)to signal almost all aspects of cellular life,ranging from cell proliferation to cell death,in a spatially and temporally regulated manner.A key aspect of this regulation is the compar...Cells utilize calcium ions(Ca^2+)to signal almost all aspects of cellular life,ranging from cell proliferation to cell death,in a spatially and temporally regulated manner.A key aspect of this regulation is the compartmen-talization of Ca^2+in various cytoplasmic organelles that act as intracellular Ca^2+stores.Whereas Ca^2+release from the large-volume Ca^2+stores,such as the endoplasmic reticulum(ER)and Golgi apparatus,are preferred for signal transduction,Ca^2+release from the small-volume individual vesicular stores that are dispersed throughout the cell,such as lysosomes,may be more useful in local regulation,such as membrane fusion and individualized vesicular movements.Conceivably,these two types of Ca^2+stores may be established,maintained or refilled via distinct mechanisms.ER stores are refilled through sustained Ca^2+influx at ER-plasma membrane(PM)membrane contact sites(MCSs).In this review,we discuss the release and refilling mechanisms of intracellular small vesicular Ca^2+stores,with a special focus on lysosomes.Recent imaging studies of Ca2+release and organelle MCSs suggest that Ca^2+exchange may occur between two types of stores,such that the small stores acquire Ca^2+from the large stores via ER-vesicle MCSs.Hence vesicular stores like lysosomes may be viewed as secondary Ca^2+stores in the cell.展开更多
In single rat pancreatic βcells, using fura-2 microfluorometry to measure [Ca2+] response upon different stimuli, the ways of calcium regulation have been studied. When the extracellular calcium concentration was 2.5...In single rat pancreatic βcells, using fura-2 microfluorometry to measure [Ca2+] response upon different stimuli, the ways of calcium regulation have been studied. When the extracellular calcium concentration was 2.5 mmol/L, either 60 mmol/L KCI, 20 mmol/L D-glucose or 0.1 mmol/L tolbutamide induced increase in [Ca2+]. Such increase in [Ca2+] was absent when the same stimuli were applied under zero extracellular calcium. These results indicate that the increase of [Ca2+] is induced by the activation of voltage-dependent calcium channels in p celis. The manifold forms of [Ca2+] change induced by glucose imply that the effects of glucose are complex. 5 mmol/L caffeine or 5 mmol/L MCh increase the [Ca2+], which is independent of the external calcium, suggesting that [Ca2+] can be regulated by Ca2+ release from not only the IP3-sensitive but also the ryanodine sensitive calcium stores in p celis. The latency of Ca responses for IP3 pathway (5 s) is faster than that for ryanodine pathway (30 s), it is展开更多
In many animals,catabolic and anabolic periods are temporally separated.Migratory birds alternate energy expenditure during flight with energy accumulation during stopover.The size of the energy stores at stopover aff...In many animals,catabolic and anabolic periods are temporally separated.Migratory birds alternate energy expenditure during flight with energy accumulation during stopover.The size of the energy stores at stopover affects the decision to resume migration and thus the temporal organization of migration.We now provide data suggesting that it is not only the size of the energy stores per se that may influence migration scheduling,but also the physiological consequences of flying.In two subspecies of the northern wheatear Oenanthe oenanthe,a long-distance migrant,estimated energy stores at a stopover during autumn migration were positively related with both constitutive innate and acquired immune function,and negatively related with oxidative damage to lipids.In other words,migrants'physiological condition was associated with their energetic condition.Although time spent at stopover before sampling may have contributed to this relationship,our results suggest that migrants have to trade-off the depletion of energy stores during flight with incurring physiological costs.This will affect migrants'decisions when to start and when to terminate a migratory flight.The physiological costs associated with the depletion of energy stores may also help explaining why migrants often arrive at and depart from stopover sites with larger energy stores than expected.We propose that studies on the role of energy stores as drivers of the temporal organization of(avian)migration need to consider physiological condition,such as immunological and oxidative states.展开更多
In the last decade, technical advancements and faster Internet speeds have also led to an increasing number ofmobile devices and users. Thus, all contributors to society, whether young or old members, can use these mo...In the last decade, technical advancements and faster Internet speeds have also led to an increasing number ofmobile devices and users. Thus, all contributors to society, whether young or old members, can use these mobileapps. The use of these apps eases our daily lives, and all customers who need any type of service can accessit easily, comfortably, and efficiently through mobile apps. Particularly, Saudi Arabia greatly depends on digitalservices to assist people and visitors. Such mobile devices are used in organizing daily work schedules and services,particularly during two large occasions, Umrah and Hajj. However, pilgrims encounter mobile app issues such asslowness, conflict, unreliability, or user-unfriendliness. Pilgrims comment on these issues on mobile app platformsthrough reviews of their experiences with these digital services. Scholars have made several attempts to solve suchmobile issues by reporting bugs or non-functional requirements by utilizing user comments.However, solving suchissues is a great challenge, and the issues still exist. Therefore, this study aims to propose a hybrid deep learningmodel to classify and predict mobile app software issues encountered by millions of pilgrims during the Hajj andUmrah periods from the user perspective. Firstly, a dataset was constructed using user-generated comments fromrelevant mobile apps using natural language processing methods, including information extraction, the annotationprocess, and pre-processing steps, considering a multi-class classification problem. Then, several experimentswere conducted using common machine learning classifiers, Artificial Neural Networks (ANN), Long Short-TermMemory (LSTM), and Convolutional Neural Network Long Short-Term Memory (CNN-LSTM) architectures, toexamine the performance of the proposed model. Results show 96% in F1-score and accuracy, and the proposedmodel outperformed the mentioned models.展开更多
POLITICAL and economic volatility and the daunting challenge of global economic recovery notwithstanding,countries are seeking ways to improve people’s living environments through more scientific and people-oriented ...POLITICAL and economic volatility and the daunting challenge of global economic recovery notwithstanding,countries are seeking ways to improve people’s living environments through more scientific and people-oriented urban planning.Chinese President Xi Jinping set great store,during his recent inspection tours of Shandong,Shanghai,and Chongqing,on ecological protection and the people-oriented development principles of urban planning.展开更多
基金the National Natural Science Foundation of China(51708001).
文摘The urban grass-roots library is an important part of the public cultural service system,and also a place to carry out national reading and lifelong learning,which is of great significance to the construction of a learning society.In this paper,the development and evolution of urban grassroots libraries in China are reviewed,and the current situation and usage issues of grassroots libraries in Beijing are analyzed.Moreover,the development strategy of idea stores in London,UK is studied,and characteristics are summarized,and possible references are sought.In the new era,urban grassroots libraries should integrate into communities with multiple functions and play a more sufficient role in public education,learning and training,and other aspects.
基金the National Natural Science Foundation of China, No.30670694 the Natural Science Foundation of Anhui Province Department of Education in China, No.2006KJ361B+2 种基金 the National Science Fund for Distinguished Young Scholars of Anhui Medical University, No.GJJQ-0801 the Scientific Research Foundation for Doctor of Anhui Medical University, No. XJ2005006the Special Foundation for Young Scientists in Higher Education Institutions of Anhui Province, No.2010SQRL078
文摘BACKGROUND: Most of the currently available information on purinergic receptors (P2Rs) involved in pain transmission is based on results obtained in dorsal root ganglion or the spinal cord. However, the mechanism of P2Rs in trigeminal neuralgia remains unclear. OBJECTIVE: To investigate changes in the P2R-mediated calcium signaling pathway in nociceptive trigemJnal ganglion neurons. DESIGN, TIME AND SETTING: In vitro experiments were conducted at the Patch-Clamp Laboratory of Comprehensive Experiment Center of Anhui Medical University, China from September 2008 to June 2009. MATERIALS: Thapsigargin, caffeine, suramin, and adenosine 5'-triphosphate were purchased from Sigma, USA. METHODS: Using Fura-2-based microfluorimetry, intracellular calcium concentration ([Ca^2+]i) was measured in freshly isolated adult rat small trigeminal ganglion neurons before and after drug application. MAIN OUTCOME MEASURES: Fluorescent intensities were expressed as the ratio F340/F380 to observe [Ca^2+]i changes. RESULTS: In normal extracellular solution and Ca^2+-free solution, application of thapsigargin (1 μmol/L), a sarcoplasmic reticulum Ca^2+ pump adenosine 5'-triphosphate inhibitor, as well as caffeine (20 mmol/L), a ryanodine receptor agonist, triggered [Ca^2+]i increase in small trigeminal ganglion neurons. A similar response was induced by application of adenosine 5'-triphosphate (100 μmol/L). In Ca^2+-free conditions, adenosine 5'-triphosphate-induced [Ca^2+]i transients in small trigeminal ganglion neurons were inhibited in cells pre-treated with thapsigargin (P 〈 0.01), but not by caffeine (P 〉 0.05). In normal, extracellular solution, adenosine 5'-triphosphate-induced [Ca^2+]i transients in small trigeminal ganglion neurons were partly inhibited in cells pre-treated with thapsigargin (P 〈 0.05). CONCLUSION: Inositol-1,4, 5-triphosphate (IP3)- and ryanodine-sensitive Ca^2+ stores exist in rat nociceptive trigeminal ganglion neurons. Two pathways are involved in the purinoreceptor-mediated [Ca^2+]i rise observed in nociceptive trigeminal ganglion neurons. One pathway involves the metabotropic P2Y receptors, which are associated with the IP3 sensitive Ca^2+store, and the second pathway is coupled to ionotropic P2X receptors that induce the Ca^2+ influx.
文摘In this paper, the optimization of micro-cogeneration (μ-CHP) system sizing for convenience stores in Thailand is conducted under the present condition of fuel prices and tariff rates. The assessment of (μ-CHP) system performance is analyzed by using Primary Energy Saving (PES) Ratio for evaluating the energy performance. Also, the Annual Cost Saving Ratio (CSR) and Payback Period (PBP) are used for evaluating the economic performance of μ-CHP system. The analysis results show the optimal size of μ-CHP system under possible conditions including the operating schedule and system’s efficiency were conducted.
基金supported by the Volkswagen Stiftung(grant No.90233)to OG
文摘Alzheimer’s disease(AD)is the most common form of dementia representing a major problem for public health.In 2017 there were an estimated 50 million patients worldwide and this number is expected to almost double every 20years,reaching 75 million in 2030 and 131.5 million in 2050(https://www.alz.co.uk/research/statistics).
文摘Pop-up stores present many advantages to brands and customers.They take advantage of seasonality and events and manifest themselves in a relevant way in front of the targeted customer.Following a mixed-method approach,semi-structured interview outcomes were used to enrich the proposed research model,which was then tested by a questionnaire.Our research’s results highlighted interesting components respective to the Lebanese market’s pop-up stores;test and experimentation,collection presentation,communication and buzz creation.Test results showed that Lebanese pop-up store atmospheres are characterized by their social dimension;customers are less affected by the aesthetics and more affected by the crowd who frequents the pop-up.Results showed that customers feel happier and are more likely to stay and to spend time in the store than to make purchases.
文摘According to the reports by World Wide Web,the potential coffee consumer base has a population of 200-250 million in China with huge consumption potential,equals to the total US population.Consumption is limited at the current stage,but it is growing rapidly.China is expected to consume over 300,000 tons of coffee bean by 2020 with an average per capita consumption of 200 grams on a yearly basis.
文摘In 2019,there were 239 brick-and-mortar bookstores in Beijing receiving the support funds,including 85 characteristic bookstores,10 most beautiful bookstores and 2 most influential bookstores,with the total support fund amounting to nearly RMB 100 million.
文摘The tail latency of end-user requests,which directly impacts the user experience and the revenue,is highly related to its corresponding numerous accesses in key-value stores.The replica selection algorithm is crucial to cut the tail latency of these key-value accesses.Recently,the C3 algorithm,which creatively piggybacks the queue-size of waiting keys from replica servers for the replica selection at clients,is proposed in NSDI 2015.Although C3 improves the tail latency a lot,it suffers from the timeliness issue on the feedback information,which directly influences the replica selection.In this paper,we analysis the evaluation of queuesize of waiting keys of C3,and some findings of queue-size variation were made.It motivate us to propose the Prediction-Based Replica Selection(PRS)algorithm,which predicts the queue-size at replica servers under the poor timeliness condition,instead of utilizing the exponentially weighted moving average of the state piggybacked queue-size as in C3.Consequently,PRS can obtain more accurate queue-size at clients than C3,and thus outperforms C3 in terms of cutting the tail latency.Simulation results confirm the advantage of PRS over C3.
文摘In 2018,cosmetics stores no longer complained about the difficulty in doing business.Instead,it has been found that a fewer number of stores stuck to their business.Adopting the supermarket model for CS has just completed the function of commodity transfer.Therefore,the value of this channel has already been cannibalized by e-commerce.But the value of CS is not only reflected in commodity transfer but information transfer and service experience.If we look at the well-performed CS right now,they are either stores selling special goods or stores offering special service for shoppers to experience.
文摘“It’s horrible!How come the customer satisfaction(CS)channel is such a dismal failure?”Many complained to me.“Destined”,I responded.A.S.Watson Group(Hong Kong)Ltd.saw a significant increase in the number of physical stores to 1,000 in 2011,a benchmark for its domestic counterparts.
文摘Joseph Abboud, an apparel company from the USA, has announced plans to open its first store in China in autumn of 2008 and will open 15 stores across the country before the end of the year.
文摘This study attempted to examine the importance of storeenvironment in affecting consumers’store choice deci-sion;the relative importance among the three environ-mental factors;and consumers’expectations on store en-vironment for the casual-wear chain stores in HongKong.Julie Baker’s Three-category framework onstore environments namely ambient,design and socialfactors was adopted for investigation.The results indi-cated that the store environment was important in affect-ing consumers’selection of store for shopping.It alsorevealed that social factor was perceived relatively im-portant than ambient and design factors.Nine store ex-pectation dimensions were categorised and the resultdemonstrated that most respondents were concerned onthe social aspect in their expectation of having a satisfy-ing store environment.
文摘Developing ocean carbon sinks and improving the marine capacity to capture and store carbon dioxide is an important way to achieve carbon peaking and neutrality.THE ocean plays a vital role in regulating the global climate.It absorbs the carbon dioxide in the atmosphere and stores it through physical,chemical,and biological processes.The ocean surface dissolves about one third of the carbon dioxide released due to human activities into the atmosphere.
文摘On 13 March,the US House of Representatives passed a bill targeting short video application TikTok,requiring its Chinese owner ByteDance to divest control of the app;otherwise,the app will be removed from app stores.It is another case of the US targeting Chinese tech companies in the name of national security,as was the case with Chinese tech giant Huawei.
文摘Cells utilize calcium ions(Ca^2+)to signal almost all aspects of cellular life,ranging from cell proliferation to cell death,in a spatially and temporally regulated manner.A key aspect of this regulation is the compartmen-talization of Ca^2+in various cytoplasmic organelles that act as intracellular Ca^2+stores.Whereas Ca^2+release from the large-volume Ca^2+stores,such as the endoplasmic reticulum(ER)and Golgi apparatus,are preferred for signal transduction,Ca^2+release from the small-volume individual vesicular stores that are dispersed throughout the cell,such as lysosomes,may be more useful in local regulation,such as membrane fusion and individualized vesicular movements.Conceivably,these two types of Ca^2+stores may be established,maintained or refilled via distinct mechanisms.ER stores are refilled through sustained Ca^2+influx at ER-plasma membrane(PM)membrane contact sites(MCSs).In this review,we discuss the release and refilling mechanisms of intracellular small vesicular Ca^2+stores,with a special focus on lysosomes.Recent imaging studies of Ca2+release and organelle MCSs suggest that Ca^2+exchange may occur between two types of stores,such that the small stores acquire Ca^2+from the large stores via ER-vesicle MCSs.Hence vesicular stores like lysosomes may be viewed as secondary Ca^2+stores in the cell.
文摘In single rat pancreatic βcells, using fura-2 microfluorometry to measure [Ca2+] response upon different stimuli, the ways of calcium regulation have been studied. When the extracellular calcium concentration was 2.5 mmol/L, either 60 mmol/L KCI, 20 mmol/L D-glucose or 0.1 mmol/L tolbutamide induced increase in [Ca2+]. Such increase in [Ca2+] was absent when the same stimuli were applied under zero extracellular calcium. These results indicate that the increase of [Ca2+] is induced by the activation of voltage-dependent calcium channels in p celis. The manifold forms of [Ca2+] change induced by glucose imply that the effects of glucose are complex. 5 mmol/L caffeine or 5 mmol/L MCh increase the [Ca2+], which is independent of the external calcium, suggesting that [Ca2+] can be regulated by Ca2+ release from not only the IP3-sensitive but also the ryanodine sensitive calcium stores in p celis. The latency of Ca responses for IP3 pathway (5 s) is faster than that for ryanodine pathway (30 s), it is
基金The study was supported with grants from the Deutsch Forschungsgemeinschaft(DFG)awarded to C.E.(EI 1048/3-1)to Heiko Schmaljohann(SCHM 2647/3-1)+2 种基金the Swedish Research Council C 0361301(to C.I.)Marie Curie Career Integration Grant FP7-CIG ID:322217(to C.I.)A.H.is associated with the Centre for Animal Movement Research(CAnMove)which is financed by a Linnaeus grant(349-2007-8690)from the Swedish Research Council and Lund University.
文摘In many animals,catabolic and anabolic periods are temporally separated.Migratory birds alternate energy expenditure during flight with energy accumulation during stopover.The size of the energy stores at stopover affects the decision to resume migration and thus the temporal organization of migration.We now provide data suggesting that it is not only the size of the energy stores per se that may influence migration scheduling,but also the physiological consequences of flying.In two subspecies of the northern wheatear Oenanthe oenanthe,a long-distance migrant,estimated energy stores at a stopover during autumn migration were positively related with both constitutive innate and acquired immune function,and negatively related with oxidative damage to lipids.In other words,migrants'physiological condition was associated with their energetic condition.Although time spent at stopover before sampling may have contributed to this relationship,our results suggest that migrants have to trade-off the depletion of energy stores during flight with incurring physiological costs.This will affect migrants'decisions when to start and when to terminate a migratory flight.The physiological costs associated with the depletion of energy stores may also help explaining why migrants often arrive at and depart from stopover sites with larger energy stores than expected.We propose that studies on the role of energy stores as drivers of the temporal organization of(avian)migration need to consider physiological condition,such as immunological and oxidative states.
文摘In the last decade, technical advancements and faster Internet speeds have also led to an increasing number ofmobile devices and users. Thus, all contributors to society, whether young or old members, can use these mobileapps. The use of these apps eases our daily lives, and all customers who need any type of service can accessit easily, comfortably, and efficiently through mobile apps. Particularly, Saudi Arabia greatly depends on digitalservices to assist people and visitors. Such mobile devices are used in organizing daily work schedules and services,particularly during two large occasions, Umrah and Hajj. However, pilgrims encounter mobile app issues such asslowness, conflict, unreliability, or user-unfriendliness. Pilgrims comment on these issues on mobile app platformsthrough reviews of their experiences with these digital services. Scholars have made several attempts to solve suchmobile issues by reporting bugs or non-functional requirements by utilizing user comments.However, solving suchissues is a great challenge, and the issues still exist. Therefore, this study aims to propose a hybrid deep learningmodel to classify and predict mobile app software issues encountered by millions of pilgrims during the Hajj andUmrah periods from the user perspective. Firstly, a dataset was constructed using user-generated comments fromrelevant mobile apps using natural language processing methods, including information extraction, the annotationprocess, and pre-processing steps, considering a multi-class classification problem. Then, several experimentswere conducted using common machine learning classifiers, Artificial Neural Networks (ANN), Long Short-TermMemory (LSTM), and Convolutional Neural Network Long Short-Term Memory (CNN-LSTM) architectures, toexamine the performance of the proposed model. Results show 96% in F1-score and accuracy, and the proposedmodel outperformed the mentioned models.
文摘POLITICAL and economic volatility and the daunting challenge of global economic recovery notwithstanding,countries are seeking ways to improve people’s living environments through more scientific and people-oriented urban planning.Chinese President Xi Jinping set great store,during his recent inspection tours of Shandong,Shanghai,and Chongqing,on ecological protection and the people-oriented development principles of urban planning.