Rock sheds are widely used to prevent rockfall disasters along roads in mountainous areas.To improve the capacity of rock sheds for resisting rockfall impact,a sand and expandable polyethylene(EPE)composite cushion wa...Rock sheds are widely used to prevent rockfall disasters along roads in mountainous areas.To improve the capacity of rock sheds for resisting rockfall impact,a sand and expandable polyethylene(EPE)composite cushion was proposed.A series of model experiments of rockfall impact on rock sheds were conducted,and the buried depth of the EPE foam board in the sand layer was considered.The impact load and dynamic response of the rock shed were investigated.The results show that the maximum impact load and dynamic response of the rock shed roof are all significantly less than those of the sand cushion.Moreover,as the distance between the EPE foam board and rock shed roof decreases,the maximum rockfall impact force and impact pressure gradually decrease,and the maximum displacement,acceleration and strain of the rock shed first decrease and then change little.In addition,the vibration acceleration and vertical displacement of the rock shed roof decrease from the centre to the edge and decrease faster along the longitudinal direction than that along the transverse direction.In conclusion,the buffering effect of the sand-EPE composite cushion is better than that of the pure sand cushion,and the EPE foam board at a depth of 1/3 the thickness of the sand layer is appropriate.展开更多
Fruitlet calyx shedding in pear plants is apparently regulated via numerous pathways that involve both environmental triggers and phytohormones cues such as auxin. In this study, we found at 10 days after full bloom (...Fruitlet calyx shedding in pear plants is apparently regulated via numerous pathways that involve both environmental triggers and phytohormones cues such as auxin. In this study, we found at 10 days after full bloom (DAFB) higher levels of indoleacetic acid (IAA) and tryptophan (Trp) in calyx persistence fruitlet (CPF) than calyx shedding fruitlet (CSF) ofDanshan Suli’ pear (Pyrus bretschneideri Rhed.). Consisting with this, the activity of indolealdehyde oxidase (IAAIdO), which promotes IAA synthesis, was remarkably increased, and that of peroxidase(POD), which degrades IAA, dropped markedly in CPF but not in CSF. Further, qRT-PCR results revealed that most of 31 PbrARFs (encoding auxin response factors) in Pyrus bretschneideri were highly expressed in CPF, whereas PbrARF4, PbrARF24 and PbrARF26 were significantly downregulated in CPF vis-a-vis CSF. Phylogenetic analysis revealed that 6 PbrARFs clustered in the group III, where PbrARF4 showed the closest affinity with AtARF1 that promotes organ abscission, indicating a putative role of PbrARF4 in mediating the process of calyx shedding in pear. In fact, the ectopic overexpression of PbrARF4 in Solanum lycopersicum resulted in an earlier-formed and deeper abscission layer (AL) in the transgenic plants, whose calyxes were more prone to wilt at the mature red stage (MR) compared with the control plants (wild-type). More importantly, expression levels of the abscission genes SILS and Sl Cel2 in transgenic plants overexpressing PbrARF4 were significantly upregulated in comparation with the WT, whereas those of Sl BI and Sl TAPG2 were considerably inhibited. Further, PbrJOINTLESS and PbrIDA,the two genes related to calyx shedding in pear, were up-regulated more in CSF than CPF. The findings contribute to a better understanding of PbrARFs involved in fruitlet calyx shedding of pear, which could prove beneficial to improving the quality of pear fruit.展开更多
Rock shed is an effective protection measure against rockfall.To investigate the influences of falling rock’s shape and impact angle on the impact effect of the cushioned rock shed,a modeling approach for a rock shed...Rock shed is an effective protection measure against rockfall.To investigate the influences of falling rock’s shape and impact angle on the impact effect of the cushioned rock shed,a modeling approach for a rock shed with a cushion layer using PFC-FLAC.The granular cushion is modeled as an aggregate of discrete non-cohesion particles,while the concrete plate and the beam are modeled as zones.The falling rock with different sphericities and impact angles is modeled as a rigid assembly.The numerical model is validated by comparing the simulation results with experimental and numerical results from previous literature.This model is applied to analyze the effects of rock shape and impact angle on the dynamic interaction effects between falling rock and cushioned rock shed,including the impact force,transmitted bottom force,penetration depth,and plate deflection.The numerical results show that the variation in the falling rock’s shape has different effects on the falling rock with different impact angles.These findings could support rock shed design by revealing the limitations of the assumptions in the past research,which may result in unsafe rock sheds for some rockfall cases.展开更多
Load shedding is a major problem in Central Africa, with negative consequences for both society and the economy. However, load profile analysis can help to alleviate this problem by providing valuable information abou...Load shedding is a major problem in Central Africa, with negative consequences for both society and the economy. However, load profile analysis can help to alleviate this problem by providing valuable information about consumer demand. This information can be used by power utilities to forecast and reduce power cuts effectively. In this study, the direct method was used to create load profiles for residential feeders in Kinshasa. The results showed that load shedding on weekends results in significant financial losses and changes in people’s behavior. In November 2022 alone, load shedding was responsible for $ 23,4 08,984 and $ 2 80,9 07,808 for all year in losses. The study also found that the SAIDI index for the southern direction of the Kinshasa distribution network was 122.49 hours per feeder, on average. This means that each feeder experienced an average of 5 days of load shedding in November 2022. The SAIFI index was 20 interruptions per feeder, on average, and the CAIDI index was 6 hours, on average, before power was restored. This study also proposes ten strategies for the reduction of load shedding in the Kinshasa and central Africa power distribution network and for the improvement of its reliability, namely: Improved load forecasting, Improvement of the grid infrastructure, Scheduling of load shedding, Demand management programs, Energy efficiency initiatives, Distributed Generation, Automation and Monitoring of the Grid, Education and engagement of the consumer, Policy and regulatory assistance, and Updated load profile analysis.展开更多
The pig-on-litter system is characterized by reduced environmental pollution and high-quality pork. It has won the support of the government and the acceptance of market. It is urgent to develop the supporting facilit...The pig-on-litter system is characterized by reduced environmental pollution and high-quality pork. It has won the support of the government and the acceptance of market. It is urgent to develop the supporting facilities and products to promote the comprehensive promotion of this technology. Based on the climatic and hydro- logical conditions in Jiangsu Province, we designed the removable deep-litter breed- ing shed. Its construction costs were lower than that of ordinary water-flushed pig- gery. In addition, this breeding system would not consolidate the land. The indoor ventilation and heat-conservation performances also met the requirements by pig-on- litter system. The removable shed can be promoted as an important supporting technology for the deep-litter breeding model in the eastern China.展开更多
In order to compare the advantages and disadvantages of large-shed,middle-shed and small-shed upland seedling nurturing modes in japonica rice planting regions of North China, in this study, Tongyin 58, Tonghe 836 and...In order to compare the advantages and disadvantages of large-shed,middle-shed and small-shed upland seedling nurturing modes in japonica rice planting regions of North China, in this study, Tongyin 58, Tonghe 836 and Tonghe 835 were used as experimental materials and cultivated with large-shed, middle-shed and small-shed upland seedling nurturing modes to investigate active and effective accumulated temperature and rice seedling quality. According to the results, active and effective accumulated temperature in three different upland seedling nurturing treatments during seedling nurturing period were generally in a descending order of large shed 〉 middle shed 〉 small shed. The occurrence frequency of temperature exceeding the biological upper limit for rice growth in different upland seedling nurturing treatments demonstrated a descending order of large shed 〉 small shed 〉middle shed; the occurrence frequency of temperature below the biological lower limit demonstrated a descending order of small shed 〉 middle shed 〉 large shed.Plant height, root number, aboveground dry weight, underground dry weight and emergence rate varied significantly among different upland seedling nurturing modes,which showed a descending order of large shed 〉 middle shed 〉 small shed; leaf age and stem number in large shed was significantly higher than that in middle and small sheds, but there was no significant difference in leaf age and stem number between middle and small sheds; underground dry weight varied slightly between large and middle shed, but underground dry weight in large and middle shed was remarkably higher than that in small shed. In production, large-shed upland seedling nurturing is most appropriate technique, followed by middle-shed upland seedling nurturing. In large-shed upland seedling nurturing, ventilation and seedling hardening should be strengthened. Small-shed upland seedling nurturing technique is not recommended to be used in regions with low accumulated temperature at night. In small-shed upland seedling nurturing, the minimum temperature at night should be concerned, and heat preservation measures should be taken immediately when there is a sudden drop in temperature.展开更多
PrPSc,a misfolded,aggregation-prone isoform of the cellular prion protein(PrPC),is the infectious prion agent responsible for fatal neurodegenerative diseases of humans and other mammals.PrPSccan adopt different patho...PrPSc,a misfolded,aggregation-prone isoform of the cellular prion protein(PrPC),is the infectious prion agent responsible for fatal neurodegenerative diseases of humans and other mammals.PrPSccan adopt different pathogenic conformations(prion strains),which can be resistant to potential drugs,or acquire drug resistance,posing challenges for the development of effective therapies.Since PrPCis the obligate precursor of any prion strain and serves as the mediator of prion neurotoxicity,it represents an attractive therapeutic target fo r prion diseases.In this minireview,we briefly outline the approaches to target PrPCand discuss our recent identification of Zn(Ⅱ)-Bn PyP,a PrPC-targeting porphyrin with an unprecedented bimodal mechanism of action.We argue that in-depth understanding of the molecular mechanism by which Zn(Ⅱ)-Bn PyP targets PrPCmay lead toward the development of a new class of dual mechanism anti-prion compounds.展开更多
基金supported by the Natural Science Foundation of Sichuan Province(No.2022NSFSC1127)the Fundamental Research Funds for the Central Universities(No.2682023CX075).
文摘Rock sheds are widely used to prevent rockfall disasters along roads in mountainous areas.To improve the capacity of rock sheds for resisting rockfall impact,a sand and expandable polyethylene(EPE)composite cushion was proposed.A series of model experiments of rockfall impact on rock sheds were conducted,and the buried depth of the EPE foam board in the sand layer was considered.The impact load and dynamic response of the rock shed were investigated.The results show that the maximum impact load and dynamic response of the rock shed roof are all significantly less than those of the sand cushion.Moreover,as the distance between the EPE foam board and rock shed roof decreases,the maximum rockfall impact force and impact pressure gradually decrease,and the maximum displacement,acceleration and strain of the rock shed first decrease and then change little.In addition,the vibration acceleration and vertical displacement of the rock shed roof decrease from the centre to the edge and decrease faster along the longitudinal direction than that along the transverse direction.In conclusion,the buffering effect of the sand-EPE composite cushion is better than that of the pure sand cushion,and the EPE foam board at a depth of 1/3 the thickness of the sand layer is appropriate.
基金supported by the China Agriculture Research System (Grant No.CARS-28-14)。
文摘Fruitlet calyx shedding in pear plants is apparently regulated via numerous pathways that involve both environmental triggers and phytohormones cues such as auxin. In this study, we found at 10 days after full bloom (DAFB) higher levels of indoleacetic acid (IAA) and tryptophan (Trp) in calyx persistence fruitlet (CPF) than calyx shedding fruitlet (CSF) ofDanshan Suli’ pear (Pyrus bretschneideri Rhed.). Consisting with this, the activity of indolealdehyde oxidase (IAAIdO), which promotes IAA synthesis, was remarkably increased, and that of peroxidase(POD), which degrades IAA, dropped markedly in CPF but not in CSF. Further, qRT-PCR results revealed that most of 31 PbrARFs (encoding auxin response factors) in Pyrus bretschneideri were highly expressed in CPF, whereas PbrARF4, PbrARF24 and PbrARF26 were significantly downregulated in CPF vis-a-vis CSF. Phylogenetic analysis revealed that 6 PbrARFs clustered in the group III, where PbrARF4 showed the closest affinity with AtARF1 that promotes organ abscission, indicating a putative role of PbrARF4 in mediating the process of calyx shedding in pear. In fact, the ectopic overexpression of PbrARF4 in Solanum lycopersicum resulted in an earlier-formed and deeper abscission layer (AL) in the transgenic plants, whose calyxes were more prone to wilt at the mature red stage (MR) compared with the control plants (wild-type). More importantly, expression levels of the abscission genes SILS and Sl Cel2 in transgenic plants overexpressing PbrARF4 were significantly upregulated in comparation with the WT, whereas those of Sl BI and Sl TAPG2 were considerably inhibited. Further, PbrJOINTLESS and PbrIDA,the two genes related to calyx shedding in pear, were up-regulated more in CSF than CPF. The findings contribute to a better understanding of PbrARFs involved in fruitlet calyx shedding of pear, which could prove beneficial to improving the quality of pear fruit.
基金supported by the National Natural Science Foundation of China(Grant Nos.41941017 and U1702241).
文摘Rock shed is an effective protection measure against rockfall.To investigate the influences of falling rock’s shape and impact angle on the impact effect of the cushioned rock shed,a modeling approach for a rock shed with a cushion layer using PFC-FLAC.The granular cushion is modeled as an aggregate of discrete non-cohesion particles,while the concrete plate and the beam are modeled as zones.The falling rock with different sphericities and impact angles is modeled as a rigid assembly.The numerical model is validated by comparing the simulation results with experimental and numerical results from previous literature.This model is applied to analyze the effects of rock shape and impact angle on the dynamic interaction effects between falling rock and cushioned rock shed,including the impact force,transmitted bottom force,penetration depth,and plate deflection.The numerical results show that the variation in the falling rock’s shape has different effects on the falling rock with different impact angles.These findings could support rock shed design by revealing the limitations of the assumptions in the past research,which may result in unsafe rock sheds for some rockfall cases.
文摘Load shedding is a major problem in Central Africa, with negative consequences for both society and the economy. However, load profile analysis can help to alleviate this problem by providing valuable information about consumer demand. This information can be used by power utilities to forecast and reduce power cuts effectively. In this study, the direct method was used to create load profiles for residential feeders in Kinshasa. The results showed that load shedding on weekends results in significant financial losses and changes in people’s behavior. In November 2022 alone, load shedding was responsible for $ 23,4 08,984 and $ 2 80,9 07,808 for all year in losses. The study also found that the SAIDI index for the southern direction of the Kinshasa distribution network was 122.49 hours per feeder, on average. This means that each feeder experienced an average of 5 days of load shedding in November 2022. The SAIFI index was 20 interruptions per feeder, on average, and the CAIDI index was 6 hours, on average, before power was restored. This study also proposes ten strategies for the reduction of load shedding in the Kinshasa and central Africa power distribution network and for the improvement of its reliability, namely: Improved load forecasting, Improvement of the grid infrastructure, Scheduling of load shedding, Demand management programs, Energy efficiency initiatives, Distributed Generation, Automation and Monitoring of the Grid, Education and engagement of the consumer, Policy and regulatory assistance, and Updated load profile analysis.
基金Supported by Jiangsu Agricultural Science and Technology Innovation Fund(CX(12)5013)~~
文摘The pig-on-litter system is characterized by reduced environmental pollution and high-quality pork. It has won the support of the government and the acceptance of market. It is urgent to develop the supporting facilities and products to promote the comprehensive promotion of this technology. Based on the climatic and hydro- logical conditions in Jiangsu Province, we designed the removable deep-litter breed- ing shed. Its construction costs were lower than that of ordinary water-flushed pig- gery. In addition, this breeding system would not consolidate the land. The indoor ventilation and heat-conservation performances also met the requirements by pig-on- litter system. The removable shed can be promoted as an important supporting technology for the deep-litter breeding model in the eastern China.
基金Supported by Program for Breeding of High-yield,High-quality,Multi-resistant Rice Varieties in the Middle and East of Jilin Province(20140309002NY)~~
文摘In order to compare the advantages and disadvantages of large-shed,middle-shed and small-shed upland seedling nurturing modes in japonica rice planting regions of North China, in this study, Tongyin 58, Tonghe 836 and Tonghe 835 were used as experimental materials and cultivated with large-shed, middle-shed and small-shed upland seedling nurturing modes to investigate active and effective accumulated temperature and rice seedling quality. According to the results, active and effective accumulated temperature in three different upland seedling nurturing treatments during seedling nurturing period were generally in a descending order of large shed 〉 middle shed 〉 small shed. The occurrence frequency of temperature exceeding the biological upper limit for rice growth in different upland seedling nurturing treatments demonstrated a descending order of large shed 〉 small shed 〉middle shed; the occurrence frequency of temperature below the biological lower limit demonstrated a descending order of small shed 〉 middle shed 〉 large shed.Plant height, root number, aboveground dry weight, underground dry weight and emergence rate varied significantly among different upland seedling nurturing modes,which showed a descending order of large shed 〉 middle shed 〉 small shed; leaf age and stem number in large shed was significantly higher than that in middle and small sheds, but there was no significant difference in leaf age and stem number between middle and small sheds; underground dry weight varied slightly between large and middle shed, but underground dry weight in large and middle shed was remarkably higher than that in small shed. In production, large-shed upland seedling nurturing is most appropriate technique, followed by middle-shed upland seedling nurturing. In large-shed upland seedling nurturing, ventilation and seedling hardening should be strengthened. Small-shed upland seedling nurturing technique is not recommended to be used in regions with low accumulated temperature at night. In small-shed upland seedling nurturing, the minimum temperature at night should be concerned, and heat preservation measures should be taken immediately when there is a sudden drop in temperature.
基金supported by Telethon Italy award GGP15225(to RC and GM)Italian Ministry of Health award RF-2016-02362950(to RC and CZ)+1 种基金the CJD Foundation USA(to RC)the Associazione Italiana Encefalopatie da Prioni(AIEnP)(to RC).
文摘PrPSc,a misfolded,aggregation-prone isoform of the cellular prion protein(PrPC),is the infectious prion agent responsible for fatal neurodegenerative diseases of humans and other mammals.PrPSccan adopt different pathogenic conformations(prion strains),which can be resistant to potential drugs,or acquire drug resistance,posing challenges for the development of effective therapies.Since PrPCis the obligate precursor of any prion strain and serves as the mediator of prion neurotoxicity,it represents an attractive therapeutic target fo r prion diseases.In this minireview,we briefly outline the approaches to target PrPCand discuss our recent identification of Zn(Ⅱ)-Bn PyP,a PrPC-targeting porphyrin with an unprecedented bimodal mechanism of action.We argue that in-depth understanding of the molecular mechanism by which Zn(Ⅱ)-Bn PyP targets PrPCmay lead toward the development of a new class of dual mechanism anti-prion compounds.
