With the increasing prevalence of high-order systems in engineering applications, these systems often exhibitsignificant disturbances and can be challenging to model accurately. As a result, the active disturbance rej...With the increasing prevalence of high-order systems in engineering applications, these systems often exhibitsignificant disturbances and can be challenging to model accurately. As a result, the active disturbance rejectioncontroller (ADRC) has been widely applied in various fields. However, in controlling plant protection unmannedaerial vehicles (UAVs), which are typically large and subject to significant disturbances, load disturbances andthe possibility of multiple actuator faults during pesticide spraying pose significant challenges. To address theseissues, this paper proposes a novel fault-tolerant control method that combines a radial basis function neuralnetwork (RBFNN) with a second-order ADRC and leverages a fractional gradient descent (FGD) algorithm.We integrate the plant protection UAV model’s uncertain parameters, load disturbance parameters, and actuatorfault parameters and utilize the RBFNN for system parameter identification. The resulting ADRC exhibits loaddisturbance suppression and fault tolerance capabilities, and our proposed active fault-tolerant control law hasLyapunov stability implications. Experimental results obtained using a multi-rotor fault-tolerant test platformdemonstrate that the proposed method outperforms other control strategies regarding load disturbance suppressionand fault-tolerant performance.展开更多
Objective Shoulder arthroscopic rotator cuff tear repair is currently the main treatment for full-thickness rotator cuff tears,and postoperative rehabilitation training is essential.However,pain and limitation of acti...Objective Shoulder arthroscopic rotator cuff tear repair is currently the main treatment for full-thickness rotator cuff tears,and postoperative rehabilitation training is essential.However,pain and limitation of activity during the rehabilitation process will lead to poor results.Hence,identifying rehabilitation approaches is crucial.This study aimed to compare patient's rehabilitation outcomes and experience between rehabilitation in the supine position and in the standing position.Methods This prospective study included patients diagnosed with full-thickness rotator cuff tears who underwent shoulder arthroscopic double-row rivet repair at Sir Run Run Shaw Hospital,Zhejiang University School of Medicine from March 2019 to September 2021.The patients were randomly assigned to the standing rehabilitation exercise group(group A)and the supine rehabilitation exercise group(group B).All patients were followed up for 6 months to record and compare the visual analog scale(VAS)scores,shoulder range of motion,and rehabilitation compliance.Results Altogether,86 patients participated in the study,of whom 79 patients completed the 6-month follow-up.Groups A and B had 39 and 40 patients,respectively.Before operation,the VAS score,forward flexion and extension angle,and abduction angle were comparable between groups A and B.After operation,the patients in groups A and B all experienced a significant improvement in the VAS score,forward flexion and extension angle,and abduction angle(p<0.05).In addition,patients in group B had better VAS score(4.58±0.87 vs.5.21±1.13,p=0.0068;2.15±0.66 vs.2.51±0.51,p=0.0078;0.78±0.86 vs.1.33±0.81,p=0.0015),forward flexion and extension angle(109.30±2.87°vs.102.33±3.74°,p=0.0001;109.53±3.39°vs.104.18±2.76°,p=0.0001;125.22±6.05°vs.117.59±2.27°,p=0.0001),and abduction angle(91.78±2.77°vs.82.92±2.12°,p=0.0001;91.62±2.78°vs.82.82±1.45°,p=0.0001;109.48±3.37°vs.100.10±2.94°,p=0.0001)at 2 wk,6 wk and 6 m postoperatively.Conclusion After 6 months of follow-up,the patients who performed rehabilitation exercises in the supine position achieved better rehabilitation outcomes than those who performed rehabilitation exercises while standing.展开更多
Nitrogen(N)present in drinking water as dissolved nitrates can directly affect people’s health,making it important to control N pollution in water source areas.N pollution caused by agricultural fertilizers can be co...Nitrogen(N)present in drinking water as dissolved nitrates can directly affect people’s health,making it important to control N pollution in water source areas.N pollution caused by agricultural fertilizers can be controlled by reducing the amount of fertilizer applied,but pollution caused by soil and water erosion in hilly areas can only be controlled by conservation forests.The catchment area around Fushi Reservoir was selected as a test site and mechanisms of N loss from a vertical spatial perspective through field observations were determined.The main N losses occurred from June to September,accounting for 85.9-95.9%of the annual loss,with the losses in June and July accounting for 46.0%of the total,and in August and September for 41.9%.The N leakage from the water source area was effectively reduced by 38.2%through the optimization of the stand structure of the conservation forests.Establishing well-structured forests for water conservation is crucial to ensure the security of drinking water.This preliminary research lays the foundation for revealing then loss mechanisms in water source areas and improving the control of non-point source pollution in these areas.展开更多
In this paper, we report new whole-rock geochemical and zircon U–Pb data for monzogranites in the NE Xing'an block. These data constrained the petrogenesis of C type(high Sr/Y) adakitic rocks and showed the spati...In this paper, we report new whole-rock geochemical and zircon U–Pb data for monzogranites in the NE Xing'an block. These data constrained the petrogenesis of C type(high Sr/Y) adakitic rocks and showed the spatial extent of the influence of the Mongol-Okhostsk ocean tectonic regime and the collision between the Jiamusi Massif and Songliao Terrane. New zircon laser-ablation inductivity coupled plasma mass spectrometry(LA-ICP-MS) U–Pb data indicated that the monzogranites in the studied area were emplaced in the Early Jurassic(~180 Ma). These rocks were characterized by unusally high SiO_2(C67.49), and Sr(461–759 ppm), but strikingly low Y(4.63–8.06 ppm) and HREE(P HREE = 3.83–6.49 ppm, Yb = 0.5–0.77 ppm)contents, with therefore high Sr/Y(67.2–119) and(La/Yb)N(29.7–41.5) ratios, showing the geochemical characteristics of C type adakitic granite. The data displayed negligible Eu anomalies(Eu/Eu~ = 0.77–1.08), LREE-enriched and pronounced negative Nb and Ta anomalies. The C-typeadakites in the studied area were most likely derived from the partial melting of a thickened lower continental curst. The magma source is most likely dominated by amphibolites and garnet amphibolites. In combination with previously-reported data from igneous rocks from the Mesozoic in NE China, we conclude that the Xing'an block was influenced by the Mongol-Okhotsk subduction tectonic system, and experiences compressive settings from the amalgamation of the Jiamusi block in the east of the CAOB.展开更多
Objectives: The goal of this study was to measure the impact of simvastatin and atorvastatin treatment on blood brain barrier (BBB) integrity after experimental intracerebral hemorrhage (ICH). Methods: Primary ICH was...Objectives: The goal of this study was to measure the impact of simvastatin and atorvastatin treatment on blood brain barrier (BBB) integrity after experimental intracerebral hemorrhage (ICH). Methods: Primary ICH was induced in 27 male Wistar rats by stereotactic injection of100mL of autologous blood into the striatum. Rats were divided into three groups (n = 9/group): 1) oral treatment (2 mg/kg) of atorvastatin, 2) oral treatment (2 mg/kg) simvastatin, or 3) phosphate buffered saline daily starting 24-hours post-ICH and continuing daily for the next 3 days. On the fourth day, the animals underwent magnetic resonance imaging (MRI) for measurements of T1sat (a marker for BBB integrity), T2 (edema), and cerebral blood flow (CBF). After MRI, the animals were sacrificed and immunohistology or Western blotting was performed. Results: MRI data for animals receiving simvastatin treatment showed significantly reduced BBB dysfunction and improved CBF in the ICH rim compared to controls (P 0.05) 4 days after ICH. Simvastatin also significantly reduced edema (T2) in the rim at 4 days after ICH (P 0.05). Both statin-treated groups demonstrated increased occludin and endothelial barrier antigen levels within the vessel walls, indicating better preservation of BBB function (P 0.05) and increased number of blood vessels (P 0.05). Conclusions: Simvastatin treatment administered acutely after ICH protects BBB integrity as measured by MRI and correlative immunohistochemistry. There was also evidence of improved CBF and reduced edema by MRI. Conversely, atorvastatin showed a non-significant trend by MRI measurement.展开更多
Taihu Lake is located at the center of Changjiang delta region, the Lake and its effluent rivers are important water sources for 40 million around inhabitants and rapidly increasing industrial factories in Shanghai, J...Taihu Lake is located at the center of Changjiang delta region, the Lake and its effluent rivers are important water sources for 40 million around inhabitants and rapidly increasing industrial factories in Shanghai, Ji-angsu and Zhejiang. The pollutants originate mainly from acidy rain, home sewage of the vast number of inhabitants, livestock manure, agricultural fertilizers & pesticides applied over fields in the drainage basin, and the industrial sewage. Due to the kinds of pollutants, the Lake water is getting highly eutrophic, with frequent blooms of blue-green algae. Compared with point-source pollutants, diffuse pollution is much com-plicated and difficult to control. Thus combating non-point pollution (NPP) is paid much great attention. Based on analysis on source-sink of NPP in Taihu Lake basin, it is concluded that the function of forests on NPP control is multiple and important by both source reduction and sink expansion. The primary objective of planting trees through constructing forested wetlands and establishing riparian forest buffers is to control soil & water erosion, decrease agrochemicals application, and improve farming conditions in the region of Taihu Lake basin. Moreover forests help to intercept acidy rain, protect streambanks, uptake nutrients, hold up pollutants and provide habitat for wildlife.展开更多
Based on a survey of 939 farmers in Sichuan and Chongqing,this paper analyzes the influencing factors of entrepreneurial farmers' formal financial credit demands and credit constraints with Probit model. It is fou...Based on a survey of 939 farmers in Sichuan and Chongqing,this paper analyzes the influencing factors of entrepreneurial farmers' formal financial credit demands and credit constraints with Probit model. It is found that entrepreneurial farmers have strong demand for formal financial credit,which is mainly production investment demand,but the formal financial credit constraint is obvious. Family size,cognition of loan procedures and conditions have a positive effect on entrepreneurial farmers' formal financial demand,while family per capita income,the distance between family location and the nearest formal financial organization,have negative influence. The relationship between householder'age and entrepreneurial farmers' successful formal loan presents inverted U shape,and educational level presents a negative correlation with successful loan. Compared with the traditional scale agricultural business,farmers engaged in other entrepreneurial businesses would get loan from formal financial institutions more difficultly. Understanding level of the loan procedures and conditions has a positive effect on successful loan. Compared with entrepreneurial farmers without employment,employed farmers are more likely to get loans. Statistically,householder' age and educational level,entrepreneurial business choices do not have significant effect on entrepreneurial households' formal financial credit demands. Family size,family per capital income,the distance between family location and the nearest formal financial organization,and the size of loan do not have significant influence on entrepreneurial households' successful loan. To get rid of formal financial credit constraints,we must implement the incremental reform of financial institutions,promote the formal finance of the villages and towns which can adapt to the farmers' financial demand,and create a good financial environment. Meanwhile,it is necessary to give impetus to innovation of financial management,products and services,reduce credit threshold,and adapt to the characteristics and demands of entrepreneurial households.展开更多
Background and Purpose: We have previously demonstrated that 2-week treatment of experimental intracerebral hemorrhage (ICH) with a daily dose of 2 mg/kg statin starting 24 hours post-injury exerts a neuroprotective e...Background and Purpose: We have previously demonstrated that 2-week treatment of experimental intracerebral hemorrhage (ICH) with a daily dose of 2 mg/kg statin starting 24 hours post-injury exerts a neuroprotective effect. The present study extends our previous investigation and tests the effect of acute high-dose (within 24 hours) statin therapy on experimental ICH. Material and Methods: Fifty-six male wistar rats were subjected to ICHby stereotactic injection of 100 μl of autologous blood into the striatum. Rats were divided randomly into seven groups: saline control group (n = 8);10, 20 and 40 mg/kg simvastatin-treated groups (n = 8);and 10, 20 and 40 mg/kg atorvastatin-treated groups (n = 8). Simvastatin or atorvastatin were administered orally at 3 and 24 hours after ICH. Neurological functional outcome was evaluated using behavioral tests (mNSS and corner turn test) at multiple time points afterICH. Animals were sacrificed at 28 days after treatment, and histological studies were completed. Results: Acute treatment with simvastatin or atorvastatin at doses of 10 and 20 mg/kg, but not at 40 mg/kg, significantly enhanced recovery of neurological function starting from 2 weeks post-ICH and persisting for up to 4 weeks postICH. In addition, at doses of 10 mg/kg and 20 mg/kg, histological evaluations revealed that simvastatin or atorvastatin reduced tissue loss, increased cell proliferation in the subventricular zone and enhanced vascular density and synaptogenesis in the hematoma boundary zone when compared to salinetreated rats. Conclusions: Treatment with simvastatin or atorvastatin at doses of 10 and 20 mg/kg significantly improves neurological recovery after administration during the first 24 hours after ICH. Decreased tissue loss, increased cell proliferation and vascularity likely contribute to improved functional recovery in rats treated with statins after ICH.展开更多
On December 21,2020,The State Council Information Office issued a white paper titled"China's Energy Development in the New Era,"in which the installed capacity of hydropower,wind power,photovoltaic power...On December 21,2020,The State Council Information Office issued a white paper titled"China's Energy Development in the New Era,"in which the installed capacity of hydropower,wind power,photovoltaic power and biomass power generation in China ranked first in the world[1].Solar photovoltaic power generation is the most important development direction of clean energy in the world.It is an important energy strategy to combine it with the field of construction in China.This paper mainly introduces the characteristics and problems of the key technologies of solar photovoltaic building integration,and explores its future development direction and ways,in order to constantly promote the industrialization of new energy technology in China.展开更多
Poverty reduction is a world-wide concern.At the end of 2017,according to the rural poverty standard in China,there were 30.46 million poor in China.However,complete poverty alleviation by the end of 2020 had been ach...Poverty reduction is a world-wide concern.At the end of 2017,according to the rural poverty standard in China,there were 30.46 million poor in China.However,complete poverty alleviation by the end of 2020 had been achieved.This is significant and complicated,especially as poverty-stricken areas and ecologically fragile areas overlap.During the process of poverty alleviation,the development of forestry projects was not only conducive to improving the environment but also an important way to reduce poverty.Therefore,based on an analysis of the causes of poverty-stricken areas,this study examined successful cases in different regions and proposed ways to promote economic growth:providing state subsidies for tree planting and forest maintenance;developing undergrowth economy;and/or initiating an industrial chain.It also introduces principles to promote forestry progress,according to local conditions,keeping a balance between economic development and the environment.This study provides effective ways to promote forestry development and rural poverty alleviation.展开更多
By using angle-resolvea photoemission spectroscopy(ARPES) combined with the first-principies electronic structure calculations,we report the quantized states at the surface of a single crystal 2 H-TaSe_(2).We have obs...By using angle-resolvea photoemission spectroscopy(ARPES) combined with the first-principies electronic structure calculations,we report the quantized states at the surface of a single crystal 2 H-TaSe_(2).We have observed sub-bands of quantized states at the three-dimensional Brillouin zone center due to a highly dispersive band with light effective mass along k_(z) direction.The quantized sub-bands shift upward towards E_(F) while the bulk band at Γ shifts downward with the decrease of temperature across charge density wave(CDW) formation.The band shifts could be intimately related to the CDW.While neither the two-dimensional Fermi-surface nesting nor purely strong electron-phonon coupling can explain the mechanism of CDW in 2 H-TaSe_(2),our experiment may ignite the interest in understanding the CDW mechanism in this family.展开更多
Eleven strains of duck Tembusu virus(TMUV)were isolated from diseased ducks at different duck farms in South China during 2011–2015,and their whole genomes were sequenced.The 11 isolated strains shared high sequence ...Eleven strains of duck Tembusu virus(TMUV)were isolated from diseased ducks at different duck farms in South China during 2011–2015,and their whole genomes were sequenced.The 11 isolated strains shared high sequence identity from 95.9%to 99.5%.Phylogenetic analysis revealed that all TMUV strains isolated after 2010 are clustered into two distinct branches,one branch comprising 2 Malaysian strains,and the other branch comprising all Chinese and Thai strains forming Chinese cluster 1 and Chinese cluster 2.Five of the 11 isolated strains were closely related to classical Chinese strains(BYD)belonging to Chinese cluster 1,and the remaining 6 isolated strains were closely related to strains newly isolated in South China and Thailand,belonging to Chinese cluster 2(a mixed China-Thailand cluster).Phylogenetic analysis of the partial E and NS 5 gene of TMUVs also showed the similar results.The results collectively showed a new trend of TMUV disease that two Chinese clusters of TMUV have been concurrently circulating in South China.This study provides practical guidance for preparing vaccines against TMUV in South China.展开更多
New type professional farmers are farmers who possess certain resources and capitals,have certain extent of spirit of entrepreneurship,and are fully capable of obtaining and allocating resources related to agricultura...New type professional farmers are farmers who possess certain resources and capitals,have certain extent of spirit of entrepreneurship,and are fully capable of obtaining and allocating resources related to agricultural production and management,and engaged in agricultural production and management for obtaining average profit.Cultivation of new type professional farmers should be promoted in the process and at the background of"coordinated development of industrialization,informationization,urbanization and agricultural modernization".It should establish a proper cultivation subject system consisting of government,enterprises,rural communities and nonprofit organizations.Relying on multiple motive forces,efforts should be concentrated on cultivating those farmers with enterprising,highly innovative and learning ability,to guide traditional farmers to change into learning,enterprising and innovative ones.In addition,cultivation of new type professional farmers must rely on farmer education and training,modern agricultural development,increase in agricultural comparative advantage,innovation of rural management system and mechanism,multiple types of agricultural operation on a fairly large scale,as well as construction and regulation of new rural communities.Finally,it is recommended to provide system guarantee from long-term input mechanism of new type professional farmer education and training,incentive and restrictive mechanism of new type professional farmer cultivation,and construction of favorable environment for agricultural entrepreneurship.展开更多
Currently, China is home to more than four million hectares of oil plants nationwide, and 154 kinds of energy trees could produce seeds containing more than 40 percent of oil, with total production of the seeds totali...Currently, China is home to more than four million hectares of oil plants nationwide, and 154 kinds of energy trees could produce seeds containing more than 40 percent of oil, with total production of the seeds totaling five million tons. Another 57 million hectares of waste land are available and suitable for planting trees for the production of forest-based bioenergy, of which there is 630,000 hm2 beach land in the middle and lower reaches of Yangtze River where is suited for poplar growing. In order to approach the potential of poplar biomass production, the test was conducted in the paper. The result indicated that in the poplar forest ecosystem the herbaceous biomass production was 15.554 t/hm2. While biomass production for trees was 43.164 t/hm2, totally in the poplar plantation ecosystem biomass production reached 58.718 t/hm2. As well, poplars growing added incomes for local farmers.展开更多
Previous studies have demonstrated that statins improve neurological outcome and promote neuro-vascular recovery after ICH. This study is designed to examine whether simvastatin and atorvastatin affect levels of growt...Previous studies have demonstrated that statins improve neurological outcome and promote neuro-vascular recovery after ICH. This study is designed to examine whether simvastatin and atorvastatin affect levels of growth factors and activate the Akt signaling pathway during the recovery phase after intracerebral hemorrhage (ICH) in rats. Sixty (60) male Wistar rats were subjected to ICH by stereotactic injecttion of 100 μL of autologous blood into the striatum and were treated with or without simvastatin or atorvastatin. Neurological functional outcome was evaluated by behavioral tests (mNSS and corner turn test) at different time points after ICH. Brain extracts were utilized for Enzyme-linked immunosorbent assay (ELISA) analyses to measure vascular endothelial growth factor (VEGF);brain-derived neurotrophin factor (BDNF) expression, and nerve growth factor (NGF). Western blot was used to measure the changes in the Akt-mediated signaling pathway. Both the simvastatin and atorvastatin-treated animals had significant neurological improvement at 2 weeks post-ICH. Simvastatin and atorvastatin treatment increased the expression of BDNF, VEGF and NGF in both low- and high-dose groups at 7 days after ICH (p < 0.05). Phosphorylation of Akt, glycogen synthase kinase-3β (GSK-3β), and cAMP response element-binding proteins (CREB) were also increased at 7 days after statin treatment. These results suggest that the therapeutic effects of statins after experimental ICH may be mediated by the transient induction of BDNF, VEGF and NGF expression and the activation of the Akt-mediated signaling pathway.展开更多
BIM technology entered China at the beginning of this century and has played a prominent role in many industries,Firstly,it is applied in design enterprises,and then extends to construction enterprises,with emphasis o...BIM technology entered China at the beginning of this century and has played a prominent role in many industries,Firstly,it is applied in design enterprises,and then extends to construction enterprises,with emphasis on construction engineering.As the main force in the development of the construction industry,construction enterprises pay more and more attention to the learning and application of BIM in enterprises.BIM technology will bring more possibilities to construction equipment.With the development of The Times,the original teaching technology has been unable to meet and achieve students'future career needs and goals.This paper follows closely the steps of teaching reform,With the application of BIM technology as the entry point.The reform and innovation of BIM are deeply integrated into the professional core courses,curriculum design and graduation design,etc,in order to keep up with the industry demand and employment guidance,improve the social competitiveness of student’s employment.展开更多
基金the 2021 Key Project of Natural Science and Technology of Yangzhou Polytechnic Institute,Active Disturbance Rejection and Fault-Tolerant Control of Multi-Rotor Plant ProtectionUAV Based on QBall-X4(Grant Number 2021xjzk002).
文摘With the increasing prevalence of high-order systems in engineering applications, these systems often exhibitsignificant disturbances and can be challenging to model accurately. As a result, the active disturbance rejectioncontroller (ADRC) has been widely applied in various fields. However, in controlling plant protection unmannedaerial vehicles (UAVs), which are typically large and subject to significant disturbances, load disturbances andthe possibility of multiple actuator faults during pesticide spraying pose significant challenges. To address theseissues, this paper proposes a novel fault-tolerant control method that combines a radial basis function neuralnetwork (RBFNN) with a second-order ADRC and leverages a fractional gradient descent (FGD) algorithm.We integrate the plant protection UAV model’s uncertain parameters, load disturbance parameters, and actuatorfault parameters and utilize the RBFNN for system parameter identification. The resulting ADRC exhibits loaddisturbance suppression and fault tolerance capabilities, and our proposed active fault-tolerant control law hasLyapunov stability implications. Experimental results obtained using a multi-rotor fault-tolerant test platformdemonstrate that the proposed method outperforms other control strategies regarding load disturbance suppressionand fault-tolerant performance.
文摘Objective Shoulder arthroscopic rotator cuff tear repair is currently the main treatment for full-thickness rotator cuff tears,and postoperative rehabilitation training is essential.However,pain and limitation of activity during the rehabilitation process will lead to poor results.Hence,identifying rehabilitation approaches is crucial.This study aimed to compare patient's rehabilitation outcomes and experience between rehabilitation in the supine position and in the standing position.Methods This prospective study included patients diagnosed with full-thickness rotator cuff tears who underwent shoulder arthroscopic double-row rivet repair at Sir Run Run Shaw Hospital,Zhejiang University School of Medicine from March 2019 to September 2021.The patients were randomly assigned to the standing rehabilitation exercise group(group A)and the supine rehabilitation exercise group(group B).All patients were followed up for 6 months to record and compare the visual analog scale(VAS)scores,shoulder range of motion,and rehabilitation compliance.Results Altogether,86 patients participated in the study,of whom 79 patients completed the 6-month follow-up.Groups A and B had 39 and 40 patients,respectively.Before operation,the VAS score,forward flexion and extension angle,and abduction angle were comparable between groups A and B.After operation,the patients in groups A and B all experienced a significant improvement in the VAS score,forward flexion and extension angle,and abduction angle(p<0.05).In addition,patients in group B had better VAS score(4.58±0.87 vs.5.21±1.13,p=0.0068;2.15±0.66 vs.2.51±0.51,p=0.0078;0.78±0.86 vs.1.33±0.81,p=0.0015),forward flexion and extension angle(109.30±2.87°vs.102.33±3.74°,p=0.0001;109.53±3.39°vs.104.18±2.76°,p=0.0001;125.22±6.05°vs.117.59±2.27°,p=0.0001),and abduction angle(91.78±2.77°vs.82.92±2.12°,p=0.0001;91.62±2.78°vs.82.82±1.45°,p=0.0001;109.48±3.37°vs.100.10±2.94°,p=0.0001)at 2 wk,6 wk and 6 m postoperatively.Conclusion After 6 months of follow-up,the patients who performed rehabilitation exercises in the supine position achieved better rehabilitation outcomes than those who performed rehabilitation exercises while standing.
基金supported by Zhejiang A&F University(2022LFR083)Key R&D Program of Zhejiang Province(2021C02038)the International Centre for Bamboo and Rattan(1632021006)。
文摘Nitrogen(N)present in drinking water as dissolved nitrates can directly affect people’s health,making it important to control N pollution in water source areas.N pollution caused by agricultural fertilizers can be controlled by reducing the amount of fertilizer applied,but pollution caused by soil and water erosion in hilly areas can only be controlled by conservation forests.The catchment area around Fushi Reservoir was selected as a test site and mechanisms of N loss from a vertical spatial perspective through field observations were determined.The main N losses occurred from June to September,accounting for 85.9-95.9%of the annual loss,with the losses in June and July accounting for 46.0%of the total,and in August and September for 41.9%.The N leakage from the water source area was effectively reduced by 38.2%through the optimization of the stand structure of the conservation forests.Establishing well-structured forests for water conservation is crucial to ensure the security of drinking water.This preliminary research lays the foundation for revealing then loss mechanisms in water source areas and improving the control of non-point source pollution in these areas.
基金supported by the regional geology and mineralization research program of Heilongjiang province (HLJKD201417)
文摘In this paper, we report new whole-rock geochemical and zircon U–Pb data for monzogranites in the NE Xing'an block. These data constrained the petrogenesis of C type(high Sr/Y) adakitic rocks and showed the spatial extent of the influence of the Mongol-Okhostsk ocean tectonic regime and the collision between the Jiamusi Massif and Songliao Terrane. New zircon laser-ablation inductivity coupled plasma mass spectrometry(LA-ICP-MS) U–Pb data indicated that the monzogranites in the studied area were emplaced in the Early Jurassic(~180 Ma). These rocks were characterized by unusally high SiO_2(C67.49), and Sr(461–759 ppm), but strikingly low Y(4.63–8.06 ppm) and HREE(P HREE = 3.83–6.49 ppm, Yb = 0.5–0.77 ppm)contents, with therefore high Sr/Y(67.2–119) and(La/Yb)N(29.7–41.5) ratios, showing the geochemical characteristics of C type adakitic granite. The data displayed negligible Eu anomalies(Eu/Eu~ = 0.77–1.08), LREE-enriched and pronounced negative Nb and Ta anomalies. The C-typeadakites in the studied area were most likely derived from the partial melting of a thickened lower continental curst. The magma source is most likely dominated by amphibolites and garnet amphibolites. In combination with previously-reported data from igneous rocks from the Mesozoic in NE China, we conclude that the Xing'an block was influenced by the Mongol-Okhotsk subduction tectonic system, and experiences compressive settings from the amalgamation of the Jiamusi block in the east of the CAOB.
文摘Objectives: The goal of this study was to measure the impact of simvastatin and atorvastatin treatment on blood brain barrier (BBB) integrity after experimental intracerebral hemorrhage (ICH). Methods: Primary ICH was induced in 27 male Wistar rats by stereotactic injection of100mL of autologous blood into the striatum. Rats were divided into three groups (n = 9/group): 1) oral treatment (2 mg/kg) of atorvastatin, 2) oral treatment (2 mg/kg) simvastatin, or 3) phosphate buffered saline daily starting 24-hours post-ICH and continuing daily for the next 3 days. On the fourth day, the animals underwent magnetic resonance imaging (MRI) for measurements of T1sat (a marker for BBB integrity), T2 (edema), and cerebral blood flow (CBF). After MRI, the animals were sacrificed and immunohistology or Western blotting was performed. Results: MRI data for animals receiving simvastatin treatment showed significantly reduced BBB dysfunction and improved CBF in the ICH rim compared to controls (P 0.05) 4 days after ICH. Simvastatin also significantly reduced edema (T2) in the rim at 4 days after ICH (P 0.05). Both statin-treated groups demonstrated increased occludin and endothelial barrier antigen levels within the vessel walls, indicating better preservation of BBB function (P 0.05) and increased number of blood vessels (P 0.05). Conclusions: Simvastatin treatment administered acutely after ICH protects BBB integrity as measured by MRI and correlative immunohistochemistry. There was also evidence of improved CBF and reduced edema by MRI. Conversely, atorvastatin showed a non-significant trend by MRI measurement.
文摘Taihu Lake is located at the center of Changjiang delta region, the Lake and its effluent rivers are important water sources for 40 million around inhabitants and rapidly increasing industrial factories in Shanghai, Ji-angsu and Zhejiang. The pollutants originate mainly from acidy rain, home sewage of the vast number of inhabitants, livestock manure, agricultural fertilizers & pesticides applied over fields in the drainage basin, and the industrial sewage. Due to the kinds of pollutants, the Lake water is getting highly eutrophic, with frequent blooms of blue-green algae. Compared with point-source pollutants, diffuse pollution is much com-plicated and difficult to control. Thus combating non-point pollution (NPP) is paid much great attention. Based on analysis on source-sink of NPP in Taihu Lake basin, it is concluded that the function of forests on NPP control is multiple and important by both source reduction and sink expansion. The primary objective of planting trees through constructing forested wetlands and establishing riparian forest buffers is to control soil & water erosion, decrease agrochemicals application, and improve farming conditions in the region of Taihu Lake basin. Moreover forests help to intercept acidy rain, protect streambanks, uptake nutrients, hold up pollutants and provide habitat for wildlife.
基金Supported by the National Social Science Foundation in 2010(10AGL007)Humanities and Social Sciences Cultivation Project of Southwest University in2012(12XDSK002)+1 种基金Fundamental Research Funds for the Central Universities in 2013(SWU1309315)Fundamental Research Funds for the Central Universities in 2009(SWU0909629)
文摘Based on a survey of 939 farmers in Sichuan and Chongqing,this paper analyzes the influencing factors of entrepreneurial farmers' formal financial credit demands and credit constraints with Probit model. It is found that entrepreneurial farmers have strong demand for formal financial credit,which is mainly production investment demand,but the formal financial credit constraint is obvious. Family size,cognition of loan procedures and conditions have a positive effect on entrepreneurial farmers' formal financial demand,while family per capita income,the distance between family location and the nearest formal financial organization,have negative influence. The relationship between householder'age and entrepreneurial farmers' successful formal loan presents inverted U shape,and educational level presents a negative correlation with successful loan. Compared with the traditional scale agricultural business,farmers engaged in other entrepreneurial businesses would get loan from formal financial institutions more difficultly. Understanding level of the loan procedures and conditions has a positive effect on successful loan. Compared with entrepreneurial farmers without employment,employed farmers are more likely to get loans. Statistically,householder' age and educational level,entrepreneurial business choices do not have significant effect on entrepreneurial households' formal financial credit demands. Family size,family per capital income,the distance between family location and the nearest formal financial organization,and the size of loan do not have significant influence on entrepreneurial households' successful loan. To get rid of formal financial credit constraints,we must implement the incremental reform of financial institutions,promote the formal finance of the villages and towns which can adapt to the farmers' financial demand,and create a good financial environment. Meanwhile,it is necessary to give impetus to innovation of financial management,products and services,reduce credit threshold,and adapt to the characteristics and demands of entrepreneurial households.
文摘Background and Purpose: We have previously demonstrated that 2-week treatment of experimental intracerebral hemorrhage (ICH) with a daily dose of 2 mg/kg statin starting 24 hours post-injury exerts a neuroprotective effect. The present study extends our previous investigation and tests the effect of acute high-dose (within 24 hours) statin therapy on experimental ICH. Material and Methods: Fifty-six male wistar rats were subjected to ICHby stereotactic injection of 100 μl of autologous blood into the striatum. Rats were divided randomly into seven groups: saline control group (n = 8);10, 20 and 40 mg/kg simvastatin-treated groups (n = 8);and 10, 20 and 40 mg/kg atorvastatin-treated groups (n = 8). Simvastatin or atorvastatin were administered orally at 3 and 24 hours after ICH. Neurological functional outcome was evaluated using behavioral tests (mNSS and corner turn test) at multiple time points afterICH. Animals were sacrificed at 28 days after treatment, and histological studies were completed. Results: Acute treatment with simvastatin or atorvastatin at doses of 10 and 20 mg/kg, but not at 40 mg/kg, significantly enhanced recovery of neurological function starting from 2 weeks post-ICH and persisting for up to 4 weeks postICH. In addition, at doses of 10 mg/kg and 20 mg/kg, histological evaluations revealed that simvastatin or atorvastatin reduced tissue loss, increased cell proliferation in the subventricular zone and enhanced vascular density and synaptogenesis in the hematoma boundary zone when compared to salinetreated rats. Conclusions: Treatment with simvastatin or atorvastatin at doses of 10 and 20 mg/kg significantly improves neurological recovery after administration during the first 24 hours after ICH. Decreased tissue loss, increased cell proliferation and vascularity likely contribute to improved functional recovery in rats treated with statins after ICH.
基金University-level Scientific Research Project of East University of Heilongjiang(Project No.HDFKY210106)。
文摘On December 21,2020,The State Council Information Office issued a white paper titled"China's Energy Development in the New Era,"in which the installed capacity of hydropower,wind power,photovoltaic power and biomass power generation in China ranked first in the world[1].Solar photovoltaic power generation is the most important development direction of clean energy in the world.It is an important energy strategy to combine it with the field of construction in China.This paper mainly introduces the characteristics and problems of the key technologies of solar photovoltaic building integration,and explores its future development direction and ways,in order to constantly promote the industrialization of new energy technology in China.
基金supported by the Fundamental Research Funds for the Central Institutes(CAFYBB2019SY014)the National Natural Science Foundation of China(31770747)。
文摘Poverty reduction is a world-wide concern.At the end of 2017,according to the rural poverty standard in China,there were 30.46 million poor in China.However,complete poverty alleviation by the end of 2020 had been achieved.This is significant and complicated,especially as poverty-stricken areas and ecologically fragile areas overlap.During the process of poverty alleviation,the development of forestry projects was not only conducive to improving the environment but also an important way to reduce poverty.Therefore,based on an analysis of the causes of poverty-stricken areas,this study examined successful cases in different regions and proposed ways to promote economic growth:providing state subsidies for tree planting and forest maintenance;developing undergrowth economy;and/or initiating an industrial chain.It also introduces principles to promote forestry progress,according to local conditions,keeping a balance between economic development and the environment.This study provides effective ways to promote forestry development and rural poverty alleviation.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11774421,11774424,11574394,11774423,11822412,and 11874047)the National Key R&D Program of China(Grant Nos.2016YFA0401002,2018YFA0307000,2016YFA0300504,and 2018FYA0305800)the Fundamental Research Funds for the Central Universities,China(Grant No.2042018kf-0030)。
文摘By using angle-resolvea photoemission spectroscopy(ARPES) combined with the first-principies electronic structure calculations,we report the quantized states at the surface of a single crystal 2 H-TaSe_(2).We have observed sub-bands of quantized states at the three-dimensional Brillouin zone center due to a highly dispersive band with light effective mass along k_(z) direction.The quantized sub-bands shift upward towards E_(F) while the bulk band at Γ shifts downward with the decrease of temperature across charge density wave(CDW) formation.The band shifts could be intimately related to the CDW.While neither the two-dimensional Fermi-surface nesting nor purely strong electron-phonon coupling can explain the mechanism of CDW in 2 H-TaSe_(2),our experiment may ignite the interest in understanding the CDW mechanism in this family.
基金Supported by the Science and Technology Planning Project of Guangdong Province,China(2017A040403015,2017A020225022)the Natural Science Foundation of Guangdong Province,China(2018B030315002)the Guangdong Province Key Laboratory of Waterfowl Healthy Breeding Open Funding(SQZS1802)
文摘Eleven strains of duck Tembusu virus(TMUV)were isolated from diseased ducks at different duck farms in South China during 2011–2015,and their whole genomes were sequenced.The 11 isolated strains shared high sequence identity from 95.9%to 99.5%.Phylogenetic analysis revealed that all TMUV strains isolated after 2010 are clustered into two distinct branches,one branch comprising 2 Malaysian strains,and the other branch comprising all Chinese and Thai strains forming Chinese cluster 1 and Chinese cluster 2.Five of the 11 isolated strains were closely related to classical Chinese strains(BYD)belonging to Chinese cluster 1,and the remaining 6 isolated strains were closely related to strains newly isolated in South China and Thailand,belonging to Chinese cluster 2(a mixed China-Thailand cluster).Phylogenetic analysis of the partial E and NS 5 gene of TMUVs also showed the similar results.The results collectively showed a new trend of TMUV disease that two Chinese clusters of TMUV have been concurrently circulating in South China.This study provides practical guidance for preparing vaccines against TMUV in South China.
基金Supported by Key Project of National Social Science Foundation(10AGL007&12ASH004)Key Project of Ministry of Education(DFA100209)+2 种基金Ph.D.Foundation Project of Southwest University(SWU1209338)Fundamental Research Funds for the Central Universities in 2013(SWU1309315)Fundamental Research Funds for the Central Universities in 2009(SWU0909629)
文摘New type professional farmers are farmers who possess certain resources and capitals,have certain extent of spirit of entrepreneurship,and are fully capable of obtaining and allocating resources related to agricultural production and management,and engaged in agricultural production and management for obtaining average profit.Cultivation of new type professional farmers should be promoted in the process and at the background of"coordinated development of industrialization,informationization,urbanization and agricultural modernization".It should establish a proper cultivation subject system consisting of government,enterprises,rural communities and nonprofit organizations.Relying on multiple motive forces,efforts should be concentrated on cultivating those farmers with enterprising,highly innovative and learning ability,to guide traditional farmers to change into learning,enterprising and innovative ones.In addition,cultivation of new type professional farmers must rely on farmer education and training,modern agricultural development,increase in agricultural comparative advantage,innovation of rural management system and mechanism,multiple types of agricultural operation on a fairly large scale,as well as construction and regulation of new rural communities.Finally,it is recommended to provide system guarantee from long-term input mechanism of new type professional farmer education and training,incentive and restrictive mechanism of new type professional farmer cultivation,and construction of favorable environment for agricultural entrepreneurship.
文摘Currently, China is home to more than four million hectares of oil plants nationwide, and 154 kinds of energy trees could produce seeds containing more than 40 percent of oil, with total production of the seeds totaling five million tons. Another 57 million hectares of waste land are available and suitable for planting trees for the production of forest-based bioenergy, of which there is 630,000 hm2 beach land in the middle and lower reaches of Yangtze River where is suited for poplar growing. In order to approach the potential of poplar biomass production, the test was conducted in the paper. The result indicated that in the poplar forest ecosystem the herbaceous biomass production was 15.554 t/hm2. While biomass production for trees was 43.164 t/hm2, totally in the poplar plantation ecosystem biomass production reached 58.718 t/hm2. As well, poplars growing added incomes for local farmers.
文摘Previous studies have demonstrated that statins improve neurological outcome and promote neuro-vascular recovery after ICH. This study is designed to examine whether simvastatin and atorvastatin affect levels of growth factors and activate the Akt signaling pathway during the recovery phase after intracerebral hemorrhage (ICH) in rats. Sixty (60) male Wistar rats were subjected to ICH by stereotactic injecttion of 100 μL of autologous blood into the striatum and were treated with or without simvastatin or atorvastatin. Neurological functional outcome was evaluated by behavioral tests (mNSS and corner turn test) at different time points after ICH. Brain extracts were utilized for Enzyme-linked immunosorbent assay (ELISA) analyses to measure vascular endothelial growth factor (VEGF);brain-derived neurotrophin factor (BDNF) expression, and nerve growth factor (NGF). Western blot was used to measure the changes in the Akt-mediated signaling pathway. Both the simvastatin and atorvastatin-treated animals had significant neurological improvement at 2 weeks post-ICH. Simvastatin and atorvastatin treatment increased the expression of BDNF, VEGF and NGF in both low- and high-dose groups at 7 days after ICH (p < 0.05). Phosphorylation of Akt, glycogen synthase kinase-3β (GSK-3β), and cAMP response element-binding proteins (CREB) were also increased at 7 days after statin treatment. These results suggest that the therapeutic effects of statins after experimental ICH may be mediated by the transient induction of BDNF, VEGF and NGF expression and the activation of the Akt-mediated signaling pathway.
基金2018 Industry-university Cooperative Education Program of the Ministry of Education(No.:201801122010)。
文摘BIM technology entered China at the beginning of this century and has played a prominent role in many industries,Firstly,it is applied in design enterprises,and then extends to construction enterprises,with emphasis on construction engineering.As the main force in the development of the construction industry,construction enterprises pay more and more attention to the learning and application of BIM in enterprises.BIM technology will bring more possibilities to construction equipment.With the development of The Times,the original teaching technology has been unable to meet and achieve students'future career needs and goals.This paper follows closely the steps of teaching reform,With the application of BIM technology as the entry point.The reform and innovation of BIM are deeply integrated into the professional core courses,curriculum design and graduation design,etc,in order to keep up with the industry demand and employment guidance,improve the social competitiveness of student’s employment.
