Optimized nitrogen(N)management can increase N-use efficiency in intercropping systems.Legume-nonlegume intercropping systems can reduce N input by exploiting biological N fixation by legumes.Measurement of N utilizat...Optimized nitrogen(N)management can increase N-use efficiency in intercropping systems.Legume-nonlegume intercropping systems can reduce N input by exploiting biological N fixation by legumes.Measurement of N utilization can help in dissecting the mechanisms underlying N uptake and utilization in legume-nonlegume intercropping systems.An experiment was performed with three planting patterns:monoculture maize(MM),monoculture soybean(SS),and maize-soybean relay intercropping(IMS),and three N application levels:zero N(NN),reduced N(RN),and conventional N(CN)to investigate crop N uptake and utilization characteristics.N recovery efficiency and 15N recovery rate of crops were higher under RN than under CN,and those under RN were higher under intercropping than under the corresponding monocultures.Compared with MM,IMS showed a lower soil N-dependent rate(SNDR)in 2012.However,the SNDR of MM rapidly declined from 86.8%in 2012 to 49.4%in 2014,whereas that of IMS declined slowly from 75.4%in 2012 to 69.4%in 2014.The interspecific N competition rate(NCRms)was higher under RN than under CN,and increased yearly.Soybean nodule dry weight and nitrogenase activities were respectively 34.2%and 12.5%higher under intercropping than in monoculture at the beginning seed stage.The amount(Ndfa)and ratio(%Ndfa)of soybean N2 fixation were significantly greater under IS than under SS.In conclusion,N fertilizer was more efficiently used under RN than under CN;in particular,the relay intercropping system promoted N fertilizer utilization in comparison with the corresponding monocultures.An intercropping system helps to maintain soil fertility because interspecific N competition promotes biological N fixation by soybean by reducing N input.Thus,a maize-soybean relay intercropping system with reduced N application is sustainable and environmentally friendly.展开更多
A series of experiments of forming hydrate from ice powders in different conditions have been carried out with constant volume method to evaluate the influence factors such as pressure, temperature, and SDS surfactant...A series of experiments of forming hydrate from ice powders in different conditions have been carried out with constant volume method to evaluate the influence factors such as pressure, temperature, and SDS surfactant. The change of temperature and pressure were collected as a function of elapsed time, which were used to calculate the gas consumption and hydrate saturation during hydrate formation(pVT method). Based on the experimental results and the analysis, it is concluded that:(1) Both initial pressure and temperature have effect on the hydrate formation and temperature plays a more important role in the process;(2) heating and secondary pressurization will promote the gas hydrate formation and enhance the hydrate saturation as a result. Meanwhile, the promotion of heating seems to be more obvious than that of secondary pressurization;(3) different concentrations of SDS surfactant have clearly influence on the saturation of gas hydrate and there is an optimal concentration to promote the hydrate formation.展开更多
The hydrogen isotopic composition of plant leaf wax(δDwax) is used as an important tool for paleohydrologic reconstruction. However, the understanding of the relative importance of environmental and biological fact...The hydrogen isotopic composition of plant leaf wax(δDwax) is used as an important tool for paleohydrologic reconstruction. However, the understanding of the relative importance of environmental and biological factors in determining δDwax values still remains incomplete. To identify the effects of soil moisture and plant physiology on δDwax values in an arid ecosystem, and to explore the implication of these values for paleoclimatic reconstruction, we measured δD values of soil water(δDwater) and δDwax values in surface soils along two distance transects extending from the lakeshore to wetland to dryland around Lake Qinghai and Lake Gahai on the northeast Qinghai-Tibetan Plateau. The results showed that the δDwater values were negatively correlated with soil water content(SWC)(R^2=0.9166), and ranged from –67‰ to –46‰ with changes in SWC from 6.2% to 42.1% in the arid areas of the Gangcha(GCh) and Gahai(GH) transects. This indicated that evaporative D-enrichment in soil water was sensitive to soil moisture in an arid ecosystem. Although the shift from grasses to shrubs with increasing aridity occurred in the arid area of the GH transect, the δDwax values in surface soils from the arid areas of the two transects still showed a negative correlation with SWC(R^2=0.6835), which may be due to the controls of primary evaporative D-enrichment in the soil water and additional transpirational D-enrichment in the leaf water on the δDwaxvalues. Our preliminary research suggested that δDwax values can potentially be applied as a paleo-humidity indicator on the northeast Qinghai-Tibetan Plateau.展开更多
Adult, male, Sprague-Dawley rats were injected with granulocyte-macrophage colony-stimulating factor-transfected bone marrow stromal cells (GM-CSF-BMSCs) into the ischemic boundary zone at 24 hours after onset of mi...Adult, male, Sprague-Dawley rats were injected with granulocyte-macrophage colony-stimulating factor-transfected bone marrow stromal cells (GM-CSF-BMSCs) into the ischemic boundary zone at 24 hours after onset of middle cerebral artery occlusion. Results showed reduced infarct volume, decreased number of apoptotic cells, improved neurological functions, increased angiogenic factor expression, and increased vascular density in the ischemic boundary zone in rats that underwent GM-CSF-BMSCs transplantation compared with the BMSCs group. Experimental findings suggested that GM-CSF-BMSCs could serve as a potential therapeutic strategy for ischemic stroke and are superior to BMSCs alone.展开更多
It is important to quantitatively understand the methane adsorption and transport mechanism in coal for an evaluation of the reserves and for its production forecast. In this work, a block coal sample was chosen to pe...It is important to quantitatively understand the methane adsorption and transport mechanism in coal for an evaluation of the reserves and for its production forecast. In this work, a block coal sample was chosen to perform the CH_4 adsorption experiments using the gravimetric method at temperatures of 293.60 K, 311.26 K, 332.98 K and 352.55 K and pressures up to 19 MPa. The excess adsorption capacity of CH_4 in dry block anthracite increased, followed by a sequence decrease with the increasing pressure. High temperature restrained the growth of the excess adsorption due to that the adsorption is an intrinsically physical and exothermic process. The excess adsorption peak decreased slowly with the increase of temperature and intersected at a pressure of more than 18 MPa; meanwhile, the pressure at the excess adsorption peak increased. The existing correlations were exanfined in terms of density rather than pressure. The DR+k correlation, with an average relative deviation of 4-0.51%, fitted our data better than the others, with an average relative deviation of up to 2.29%. The transportation characteristics of CH_4 adsorption was also investigated in this study, including the adsorption rate and diffusion in block coal. The kinetic data could be described by a modified unipore model. The adsorption rates were found to exhibit dependence on pressure and temperature at low pressures, while the calculated diffusivities exhibited little temperature dependence. In addition, the kinetic characteristics were compared between CH_4 and CO_2 adsorption on the block coal. The excess adsorption ratios of CO_2 to CH_4 obtained from the DR+k model decreased with the increasing pressure.展开更多
Parkinson's disease (PD) is a common progressive neurological disorder and is composed of motor and nonmotor symptoms. Sleep disturbances are frequent problems for patients with PD. The relationship between sleep d...Parkinson's disease (PD) is a common progressive neurological disorder and is composed of motor and nonmotor symptoms. Sleep disturbances are frequent problems for patients with PD. The relationship between sleep disturbances with Hoehn and Yahr (H&Y) staging have been demonstrated. However, the relationship between sleep disorders and H&Y is still unclear in patients with PD without dementia in Chinese PD patients. In this study, we interviewed 487 non-demented PD patients of Chinese Han descents by H&Y classification. We found that night sleep quality was significantly associated with the severity of PD (P=0.008). Panic disorder severity scale (PDSS) total scores were correlated with PD non-motor symptoms scale (PDNMS) scores (r=-0.528, P〈0.001), the Hamilton depression scale (HAMD) scores (r=-0.545, P〈0.001) and the Hamilton anxiety scale (HAMA) scores (r=-0.498, P〈0.001). Our results indicated that sleep quality deteriorated with the advancing of PD in Chinese non-demented patients with PD. Depression and anxiety may partly explain sleep disturbances in nondemented patients with PD.展开更多
Background:Atmospheric nitrogen(N)deposition is projected to increase in the next few decades,which may have a marked impact on soil-atmosphere CH_(4) fluxes.However,the impacts of increased atmospheric N depositions ...Background:Atmospheric nitrogen(N)deposition is projected to increase in the next few decades,which may have a marked impact on soil-atmosphere CH_(4) fluxes.However,the impacts of increased atmospheric N depositions on soil CH_(4) flux in tropical rainforests are still poorly understood.From January 2015 to December 2018,a field experiment was conducted in a primary tropical montane rainforest(PTMR)and a secondary tropical montane rainforest(STMR)in southern China to quantify the impact of N additions at four levels(N0:0 kg N⋅ha^(-1)⋅year^(-1);N25:25 kg N⋅ha^(-1)⋅year^(-1);N50:50 kg N⋅ha^(-1)⋅year^(-1);N100:100 kg N⋅ha^(-1)⋅year^(-1)on soil CH_(4) flux.Results:Four years of measurements showed clear seasonal variations in CH_(4) flux in all treatment plots for both forest types(PTMR and STMR),with lower rates of soil CH_(4) uptake during the wet season and higher rates of soil CH_(4) uptake during the dry season.Soil CH_(4) uptake rates were significantly and negatively correlated with both soil temperature and soil moisture for both forest types.Annual CH_(4) uptake for the N0 plots from the PTMR and STMR soils were2.20 and1.98 kg N⋅ha^(-1)⋅year^(-1),respectively.At the PTMR site,mean CH_(4) uptake compared with the N0 treatment was reduced by 19%,29%,and 36%for the N25,N50,and N100 treatments,respectively.At the STMR site,mean CH_(4) uptake compared with the N0 treatment was reduced by 15%,18%,and 38%for the N25,N50,and N100 treatments,respectively.High level N addition had a stronger inhibitory impact on soil CH_(4) uptake than did the low level N addition.Conclusion:Our data suggest that soil CH_(4) uptake in tropical rainforests is sensitive to N deposition.If atmospheric N deposition continues to increase in the future,the soil CH_(4) sink strength of tropical rainforests may weaken further.展开更多
In this study, cells from the cerebral cortex of fetal rats at pregnant 16 days were harvested and cultured with 20 μg/L neurotrophin-3. After 7 days of culture, immunocytochemical staining showed that, 22.4% of cell...In this study, cells from the cerebral cortex of fetal rats at pregnant 16 days were harvested and cultured with 20 μg/L neurotrophin-3. After 7 days of culture, immunocytochemical staining showed that, 22.4% of cells were positive for nestin, 10.5% were positive for 18-111 tubulin (neuronal marker), and 60.6% were positive for glial fibrillary acidic protein, but no cells were positive for 04 (oligodendrocytic marker). At 14 days, there were 5.6% nestin-, 9.6% 13-111 tubulin-, 81.1% glial fibrillary acidic protein-, and 2.2% O4-positive cells. In cells not treated with neurotrophin-3, some were nestin-positive, while the majority showed positive staining for glial fibdllary acidic protein. Our experimental findings indicate that neurotrophin-3 is a crucial factor for inducing neural stem cells differentiation into neurons and oligodendrocytes.展开更多
Transcriptional regulation plays a key role in the control of seed dormancy,and many transcription factors(TFs)have been documented.However,the mechanisms underlying the interactions between different TFs within a tra...Transcriptional regulation plays a key role in the control of seed dormancy,and many transcription factors(TFs)have been documented.However,the mechanisms underlying the interactions between different TFs within a transcriptional complex regulating seed dormancy remain largely unknown.Here,we showed that TF PHYTOCHROME-INTERACTING FACTOR4(PIF4)physically interacted with the abscisic acid(ABA)signaling responsive TF ABSCISIC ACID INSENSITIVE4(ABI4)to act as a transcriptional complex to promote ABA biosynthesis and signaling,finally deepening primary seed dormancy.Both pif4 and abi4 single mutants exhibited a decreased primary seed dormancy phenotype,with a synergistic effect in the pif4/abi4 double mutant.PIF4 binds to ABI4 to form a heterodimer,and ABI4 stabilizes PIF4 at the protein level,whereas PIF4 does not affect the protein stabilization of ABI4.Subsequently,both TFs independently and synergistically promoted the expression of ABI4 and NCED6,a key gene for ABA anabolism.The genetic evidence is also consistent with the phenotypic,physiological and biochemical analysis results.Altogether,this study revealed a transcriptional regulatory cascade in which the PIF4–ABI4 transcriptional activator complex synergistically enhanced seed dormancy by facilitating ABA biosynthesis and signaling.展开更多
With the development of sequencing technologies,somatic mutation analysis has become an important component in cancer research and treatment.VarDict is a commonly used somatic variant caller for this task.Although the...With the development of sequencing technologies,somatic mutation analysis has become an important component in cancer research and treatment.VarDict is a commonly used somatic variant caller for this task.Although the heuristic-based VarDict algorithm exhibits high sensitivity and versatility,it may detect higher amounts of false positive variants than callers,limiting its clinical practicality.To address this problem,we propose DeepFilter,a deep-learning based filter for VarDict,which can filter out the false positive variants detected by VarDict effectively.Our approach trains two models for insertion-deletion mutations(InDels)and single nucleotide variants(SNVs),respectively.Experiments show that DeepFilter can filter at least 98.5%of false positive variants and retain 93.5%of true positive variants for InDels and SNVs in the commonly used tumor-normal paired mode.Source code and pre-trained models are available at https://github.com/LeiHaoa/DeepFilter.展开更多
The stable carbon isotope composition(δ13 C) of lacustrine sediments, which can record changes in past environmental conditions such as the C4/C3 terrestrial vegetation composition, has been widely used for the recon...The stable carbon isotope composition(δ13 C) of lacustrine sediments, which can record changes in past environmental conditions such as the C4/C3 terrestrial vegetation composition, has been widely used for the reconstruction of terrestrial ecosystems and global climate changes. It has also been widely used in paleolimnological studies in arid northwestern China. In recent years, however, an increasing number of studies have enriched the environmental significance reflected by the stable carbon isotope geochemistry of lakes;therefore, the interpretation of lake δ13 C variations in paleoenvironmental reconstructions should be carefully evaluated from various aspects. In this paper, previous studies from the past several decades on the lacustrineδ13 C variations in arid northwestern China were reviewed, and the possible mechanisms of the δ13 C variations were discussed.Our study will provide a reference for the application of carbon isotope geochemistry in paleoenvironmental reconstructions.展开更多
The discipline of "Bio-Organic Geochemistry" is a cross research field between biogeochemistry and traditional organic geochemistry, which focuses on geochemical processes related to the biosynthesis of orga...The discipline of "Bio-Organic Geochemistry" is a cross research field between biogeochemistry and traditional organic geochemistry, which focuses on geochemical processes related to the biosynthesis of organic molecules(particularly lipids) by(micro) organisms, organic matter production by primary producers, degradation of organic matter by microbial processes recorded by retainable lipid biomarkers, and organic proxies for studies of paleo-climate, paleo-environments, paleoecology and Earth evolution. This field aims to go beyond the traditional petroleum-oriented Organic Geochemistry by integrating with biogeochemical concepts concerned mostly with biomolecules from cellular material such as DNA and lipids. A formal Chinese organization in Bio-Organic Geochemistry was established in 2012 when the first conference was held in Guangzhou. This organization has witnessed rapid growth over the past six years with focused research addressing organic proxies in paleoclimate and paleoenvironmental applications, with particular rapid development in glycerol dialkyl glycerol tetraethers-derived proxies. Most progresses in China so far are made following or paralleling the international trend in biogeochemical studies. Things have begun to change with China's ambitious initiatives in several bio-geo programs such as the Ocean Deep Drilling Program of China, the Microbial Hydrosphere Program, the Deep Carbon Observatory, and the Microbiome Program. Looking forward in the 21 st Century, the growing Chinese research community in Bio-Organic Geochemistry faces grand opportunities and challenges as Chinese scientists propel themselves toward global research frontiers.展开更多
The hydrogen isotopic composition(δD) of n-alkanes in lacustrine sediments is widely used in palaeoenvironmental studies, but the heterogeneous origins and relative contributions of these lipids provide challenges fo...The hydrogen isotopic composition(δD) of n-alkanes in lacustrine sediments is widely used in palaeoenvironmental studies, but the heterogeneous origins and relative contributions of these lipids provide challenges for the interpretation of the increasing dataset as an environment and climatic proxy. We systematically investigated n-alkane δD values from 51 submerged plants(39 Potamogeton, 1 Myriophyllum, and 11 Ruppia), 13 algae(5 Chara, 3 Cladophora, and 5 Spirogyra) and 20 terrestrial plants(10 grasses and 10 shrubs) in and around 15 lakes on the Tibetan Plateau. Our results demonstrate that δD values of C_(29) nalkane are correlated significantly with the lake water δD values both for algae(R^2=0.85, p<0.01, n=9) and submerged plants(R^2=0.90, p<0.01, n=25), indicating that δD values of these algae and submerged plants reflect the δD variation of lake water. We find that apparent hydrogen isotope fractionation factors between individual n-alkanes and water(εa/w) are not constant among different algae and submerged plants, as well as in a single genus under different liminological conditions, indicating that the biosynthesis or environmental conditions(e.g. salinity) may affect their δD values. The δD values of submerged plant Ruppia in the Xiligou Lake(a closed lake) are significant enriched in D than those of terrestrial grasses around the lake(one-way ANOVA,p<0.01), but the algae Chara in the Keluke Lake(an open lake) display similar δD values with grasses around the lake(one-way ANOVA, p=0.826>0.05), suggesting that the n-alkane δD values of the algae and submerged plants record the signal of D enrichment in lake water relative to precipitation only in closed lakes in arid and semi-arid area. For each algae and submerged plant sample, we find uniformed δD values of different chain length n-alkanes, implying that, in combination with other proxies such as Paq and Average Chain Length, the offset between the δD values of different chain length n-alkanes can help determine the source of sedimentary n-alkanes as well as inferring the hydrological characteristics of an ancient lake basin(open vs closed lake).展开更多
The plasma-enhanced chemical vapor deposition(PECVD)technique is well suited for fabricating optical filters with continuously variable refractive index profiles;however,it is not clear how the optical and structural ...The plasma-enhanced chemical vapor deposition(PECVD)technique is well suited for fabricating optical filters with continuously variable refractive index profiles;however,it is not clear how the optical and structural properties of thin films differ when deposited on different substrates.Herein,silicon nitride films were deposited on silicon,fused silica,and glass substrates by PECVD,using silane and ammonia,to investigate the effects of the substrate used on the optical properties and structures of the films.All of the deposited films were amorphous.Further,the types and amounts of Si-centered tetrahedral Si–SivN4-v bonds formed were based upon the substrates used;Si–N4 bonds with higher elemental nitrogen content were formed on Si substrates,which lead to obtaining higher refractive indices,and the Si–SiN3 bonds were mainly formed on glass and fused silica substrates.The refractive indices of the films formed on the different substrates had a maximum difference of0.05(at 550 nm),the refractive index of SiNx films formed on silicon substrates was 1.83,and the refractive indices of films formed on glass were very close to those formed on fused silica.The deposition rates of these SiNx films are similar,and the extinction coefficients of all the films were lower than 10-4.展开更多
Objectives:Amino acid profiles of whole soybean curds(WSCs)and conventional soybean curds(CSCs)were comparatively studied to 1.,evaluate their nutritional value and 2.,study the suitable soybean material to fabricate ...Objectives:Amino acid profiles of whole soybean curds(WSCs)and conventional soybean curds(CSCs)were comparatively studied to 1.,evaluate their nutritional value and 2.,study the suitable soybean material to fabricate WSCs.Materials and Methods:Nine types of soybean materials were selected to make WSCs and CSCs.Protein digestibility-corrected amino acid score(PDCAAS)and principal component analysis were selected to perform the comparative analysis of amino acid profiles of the products.Results:Total contents of amino acids in WSCs and CSCs were 41.24-54.87 mg/g and 27.77-36.82 mg/g.Content ranges of essential amino acids were 13.59-19.38 mg/g and 8.46-11.76 mg/g for WSCs and CSCs.The essential amino acid pattern of WSCs was basically close to amino acid pattern spectrum requirements except valine and sulfur amino acids.As a limiting amino acid,methionine represented less than 0.4 for PDCAAS in all soybean curds except WSCs made from relay-cropping Nandou12 and Nandou25.Conclusions:The overall quality of amino acids in WSCs was higher than that in CSCs,indicating that WSCs indeed exhibited higher nutritional value than CSCs from the viewpoint of amino acid profile.WSCs with the high nutritional value could be made using Nandou25 and relay-cropping Nandou12 as materials.展开更多
基金supported by the National Natural Science Foundation of China(31671625,31271669)the National Key Research and Development Program of China(2016YFD0300202)
文摘Optimized nitrogen(N)management can increase N-use efficiency in intercropping systems.Legume-nonlegume intercropping systems can reduce N input by exploiting biological N fixation by legumes.Measurement of N utilization can help in dissecting the mechanisms underlying N uptake and utilization in legume-nonlegume intercropping systems.An experiment was performed with three planting patterns:monoculture maize(MM),monoculture soybean(SS),and maize-soybean relay intercropping(IMS),and three N application levels:zero N(NN),reduced N(RN),and conventional N(CN)to investigate crop N uptake and utilization characteristics.N recovery efficiency and 15N recovery rate of crops were higher under RN than under CN,and those under RN were higher under intercropping than under the corresponding monocultures.Compared with MM,IMS showed a lower soil N-dependent rate(SNDR)in 2012.However,the SNDR of MM rapidly declined from 86.8%in 2012 to 49.4%in 2014,whereas that of IMS declined slowly from 75.4%in 2012 to 69.4%in 2014.The interspecific N competition rate(NCRms)was higher under RN than under CN,and increased yearly.Soybean nodule dry weight and nitrogenase activities were respectively 34.2%and 12.5%higher under intercropping than in monoculture at the beginning seed stage.The amount(Ndfa)and ratio(%Ndfa)of soybean N2 fixation were significantly greater under IS than under SS.In conclusion,N fertilizer was more efficiently used under RN than under CN;in particular,the relay intercropping system promoted N fertilizer utilization in comparison with the corresponding monocultures.An intercropping system helps to maintain soil fertility because interspecific N competition promotes biological N fixation by soybean by reducing N input.Thus,a maize-soybean relay intercropping system with reduced N application is sustainable and environmentally friendly.
基金Supported by the National Natural Science Foundation of China(51436003,51676024and 51509032)the National Key Research and Development Program of China(2017YFC0307305,2016YFC0304001,2017YFC0307705)
文摘A series of experiments of forming hydrate from ice powders in different conditions have been carried out with constant volume method to evaluate the influence factors such as pressure, temperature, and SDS surfactant. The change of temperature and pressure were collected as a function of elapsed time, which were used to calculate the gas consumption and hydrate saturation during hydrate formation(pVT method). Based on the experimental results and the analysis, it is concluded that:(1) Both initial pressure and temperature have effect on the hydrate formation and temperature plays a more important role in the process;(2) heating and secondary pressurization will promote the gas hydrate formation and enhance the hydrate saturation as a result. Meanwhile, the promotion of heating seems to be more obvious than that of secondary pressurization;(3) different concentrations of SDS surfactant have clearly influence on the saturation of gas hydrate and there is an optimal concentration to promote the hydrate formation.
基金supported by the National Basic Research Program of China (2013CB955901)the National Natural Science Foundation of China (41073018)
文摘The hydrogen isotopic composition of plant leaf wax(δDwax) is used as an important tool for paleohydrologic reconstruction. However, the understanding of the relative importance of environmental and biological factors in determining δDwax values still remains incomplete. To identify the effects of soil moisture and plant physiology on δDwax values in an arid ecosystem, and to explore the implication of these values for paleoclimatic reconstruction, we measured δD values of soil water(δDwater) and δDwax values in surface soils along two distance transects extending from the lakeshore to wetland to dryland around Lake Qinghai and Lake Gahai on the northeast Qinghai-Tibetan Plateau. The results showed that the δDwater values were negatively correlated with soil water content(SWC)(R^2=0.9166), and ranged from –67‰ to –46‰ with changes in SWC from 6.2% to 42.1% in the arid areas of the Gangcha(GCh) and Gahai(GH) transects. This indicated that evaporative D-enrichment in soil water was sensitive to soil moisture in an arid ecosystem. Although the shift from grasses to shrubs with increasing aridity occurred in the arid area of the GH transect, the δDwax values in surface soils from the arid areas of the two transects still showed a negative correlation with SWC(R^2=0.6835), which may be due to the controls of primary evaporative D-enrichment in the soil water and additional transpirational D-enrichment in the leaf water on the δDwaxvalues. Our preliminary research suggested that δDwax values can potentially be applied as a paleo-humidity indicator on the northeast Qinghai-Tibetan Plateau.
基金supported by a grant from "135 Project" Foundation of the Public Health Department of Jiangsu Province,ChinaNanjing Medical Science and Technique Development Foundation
文摘Adult, male, Sprague-Dawley rats were injected with granulocyte-macrophage colony-stimulating factor-transfected bone marrow stromal cells (GM-CSF-BMSCs) into the ischemic boundary zone at 24 hours after onset of middle cerebral artery occlusion. Results showed reduced infarct volume, decreased number of apoptotic cells, improved neurological functions, increased angiogenic factor expression, and increased vascular density in the ischemic boundary zone in rats that underwent GM-CSF-BMSCs transplantation compared with the BMSCs group. Experimental findings suggested that GM-CSF-BMSCs could serve as a potential therapeutic strategy for ischemic stroke and are superior to BMSCs alone.
基金supported by Liaoning Provincial Natural Science Foundation of China(201202028)the National Program on the Key Basic Research Project(No.2011CB707304)+1 种基金the National Natural Science Foundation of China(No.51006016)the China Scholarship Council
文摘It is important to quantitatively understand the methane adsorption and transport mechanism in coal for an evaluation of the reserves and for its production forecast. In this work, a block coal sample was chosen to perform the CH_4 adsorption experiments using the gravimetric method at temperatures of 293.60 K, 311.26 K, 332.98 K and 352.55 K and pressures up to 19 MPa. The excess adsorption capacity of CH_4 in dry block anthracite increased, followed by a sequence decrease with the increasing pressure. High temperature restrained the growth of the excess adsorption due to that the adsorption is an intrinsically physical and exothermic process. The excess adsorption peak decreased slowly with the increase of temperature and intersected at a pressure of more than 18 MPa; meanwhile, the pressure at the excess adsorption peak increased. The existing correlations were exanfined in terms of density rather than pressure. The DR+k correlation, with an average relative deviation of 4-0.51%, fitted our data better than the others, with an average relative deviation of up to 2.29%. The transportation characteristics of CH_4 adsorption was also investigated in this study, including the adsorption rate and diffusion in block coal. The kinetic data could be described by a modified unipore model. The adsorption rates were found to exhibit dependence on pressure and temperature at low pressures, while the calculated diffusivities exhibited little temperature dependence. In addition, the kinetic characteristics were compared between CH_4 and CO_2 adsorption on the block coal. The excess adsorption ratios of CO_2 to CH_4 obtained from the DR+k model decreased with the increasing pressure.
基金supported by Medical Science and Technology Development Foundation,Nanjing Department of Health(No.ZKX12037)the Opening Project of Jiangsu Key Laboratory of Neurodegeneration,Nanjing Medical University(No.SJ11KF03)
文摘Parkinson's disease (PD) is a common progressive neurological disorder and is composed of motor and nonmotor symptoms. Sleep disturbances are frequent problems for patients with PD. The relationship between sleep disturbances with Hoehn and Yahr (H&Y) staging have been demonstrated. However, the relationship between sleep disorders and H&Y is still unclear in patients with PD without dementia in Chinese PD patients. In this study, we interviewed 487 non-demented PD patients of Chinese Han descents by H&Y classification. We found that night sleep quality was significantly associated with the severity of PD (P=0.008). Panic disorder severity scale (PDSS) total scores were correlated with PD non-motor symptoms scale (PDNMS) scores (r=-0.528, P〈0.001), the Hamilton depression scale (HAMD) scores (r=-0.545, P〈0.001) and the Hamilton anxiety scale (HAMA) scores (r=-0.498, P〈0.001). Our results indicated that sleep quality deteriorated with the advancing of PD in Chinese non-demented patients with PD. Depression and anxiety may partly explain sleep disturbances in nondemented patients with PD.
基金funded by the National Key R&D Program of China(No.2016YFC0500203)a Natural Sciences and Engineering Research Council of Canada Discovery Grant.
文摘Background:Atmospheric nitrogen(N)deposition is projected to increase in the next few decades,which may have a marked impact on soil-atmosphere CH_(4) fluxes.However,the impacts of increased atmospheric N depositions on soil CH_(4) flux in tropical rainforests are still poorly understood.From January 2015 to December 2018,a field experiment was conducted in a primary tropical montane rainforest(PTMR)and a secondary tropical montane rainforest(STMR)in southern China to quantify the impact of N additions at four levels(N0:0 kg N⋅ha^(-1)⋅year^(-1);N25:25 kg N⋅ha^(-1)⋅year^(-1);N50:50 kg N⋅ha^(-1)⋅year^(-1);N100:100 kg N⋅ha^(-1)⋅year^(-1)on soil CH_(4) flux.Results:Four years of measurements showed clear seasonal variations in CH_(4) flux in all treatment plots for both forest types(PTMR and STMR),with lower rates of soil CH_(4) uptake during the wet season and higher rates of soil CH_(4) uptake during the dry season.Soil CH_(4) uptake rates were significantly and negatively correlated with both soil temperature and soil moisture for both forest types.Annual CH_(4) uptake for the N0 plots from the PTMR and STMR soils were2.20 and1.98 kg N⋅ha^(-1)⋅year^(-1),respectively.At the PTMR site,mean CH_(4) uptake compared with the N0 treatment was reduced by 19%,29%,and 36%for the N25,N50,and N100 treatments,respectively.At the STMR site,mean CH_(4) uptake compared with the N0 treatment was reduced by 15%,18%,and 38%for the N25,N50,and N100 treatments,respectively.High level N addition had a stronger inhibitory impact on soil CH_(4) uptake than did the low level N addition.Conclusion:Our data suggest that soil CH_(4) uptake in tropical rainforests is sensitive to N deposition.If atmospheric N deposition continues to increase in the future,the soil CH_(4) sink strength of tropical rainforests may weaken further.
基金The National Natural Science Foundation of China,Medical Scientific Research of Zhejiang Province
文摘In this study, cells from the cerebral cortex of fetal rats at pregnant 16 days were harvested and cultured with 20 μg/L neurotrophin-3. After 7 days of culture, immunocytochemical staining showed that, 22.4% of cells were positive for nestin, 10.5% were positive for 18-111 tubulin (neuronal marker), and 60.6% were positive for glial fibrillary acidic protein, but no cells were positive for 04 (oligodendrocytic marker). At 14 days, there were 5.6% nestin-, 9.6% 13-111 tubulin-, 81.1% glial fibrillary acidic protein-, and 2.2% O4-positive cells. In cells not treated with neurotrophin-3, some were nestin-positive, while the majority showed positive staining for glial fibdllary acidic protein. Our experimental findings indicate that neurotrophin-3 is a crucial factor for inducing neural stem cells differentiation into neurons and oligodendrocytes.
基金supported by the National Natural Science Foundation of China(31872804 and 32101670)Natural Science Basic Research Program of Shaanxi(2024JC-YBMS-151)+3 种基金Shaanxi Fundamental Science Research Project for Chemistry&Biology(22JHQ054 and 22JHZ007)GuangDong Basic and Applied Basic Research Foundation(2021A1515110341)the Innovation Foundation for Doctoral Dissertations of Northwestern Polytechnical University(CX2021040,CX2022079 and CX2023096)Postdoctoral Research Foundation of China(2021M692644,2021M702674)。
文摘Transcriptional regulation plays a key role in the control of seed dormancy,and many transcription factors(TFs)have been documented.However,the mechanisms underlying the interactions between different TFs within a transcriptional complex regulating seed dormancy remain largely unknown.Here,we showed that TF PHYTOCHROME-INTERACTING FACTOR4(PIF4)physically interacted with the abscisic acid(ABA)signaling responsive TF ABSCISIC ACID INSENSITIVE4(ABI4)to act as a transcriptional complex to promote ABA biosynthesis and signaling,finally deepening primary seed dormancy.Both pif4 and abi4 single mutants exhibited a decreased primary seed dormancy phenotype,with a synergistic effect in the pif4/abi4 double mutant.PIF4 binds to ABI4 to form a heterodimer,and ABI4 stabilizes PIF4 at the protein level,whereas PIF4 does not affect the protein stabilization of ABI4.Subsequently,both TFs independently and synergistically promoted the expression of ABI4 and NCED6,a key gene for ABA anabolism.The genetic evidence is also consistent with the phenotypic,physiological and biochemical analysis results.Altogether,this study revealed a transcriptional regulatory cascade in which the PIF4–ABI4 transcriptional activator complex synergistically enhanced seed dormancy by facilitating ABA biosynthesis and signaling.
基金supported by Pan-Third Pole Environment Study for a Green Silk Road of the Strategic Priority Research Program of Chinese Academy of Sciences(XDA20090000)the National Key Research and Development Program of China(2018YFA0606400)+1 种基金Part laboratory and fieldwork costs were supported by the National Natural Science Foundation of China(41772178,91747207,and 41620104007)Field expedition was supported by the Second Tibetan Plateau Scientific Expedition(2019QZKK0601)。
基金This work was partially supported by the National Natural Science Foundation of China(NSFC)(Nos.62102231 and 61972231)the Shenzhen Basic Research Fund(No.JCYJ20180507182818013)+3 种基金the Key Project of Joint Fund of Shandong Province(No.ZR2019LZH007)Shandong Provincial Natural Science Foundation(No.ZR2021QF089)the PPP project from CSC and DAADEngineering Research Center of Digital Media Technology,Ministry of Education,China.
文摘With the development of sequencing technologies,somatic mutation analysis has become an important component in cancer research and treatment.VarDict is a commonly used somatic variant caller for this task.Although the heuristic-based VarDict algorithm exhibits high sensitivity and versatility,it may detect higher amounts of false positive variants than callers,limiting its clinical practicality.To address this problem,we propose DeepFilter,a deep-learning based filter for VarDict,which can filter out the false positive variants detected by VarDict effectively.Our approach trains two models for insertion-deletion mutations(InDels)and single nucleotide variants(SNVs),respectively.Experiments show that DeepFilter can filter at least 98.5%of false positive variants and retain 93.5%of true positive variants for InDels and SNVs in the commonly used tumor-normal paired mode.Source code and pre-trained models are available at https://github.com/LeiHaoa/DeepFilter.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences(XDB40010200 and XDA2009000004)the Program of Global Change and Mitigation+1 种基金Ministry of Science and Technology of China(2016YFA0600502)the National Natural Science Foundation of China(41877293,41672162,41977381,and 41472315)。
基金supported by the CAS Strategic Priority Research Program (Grant No. XDA05120400)
文摘The stable carbon isotope composition(δ13 C) of lacustrine sediments, which can record changes in past environmental conditions such as the C4/C3 terrestrial vegetation composition, has been widely used for the reconstruction of terrestrial ecosystems and global climate changes. It has also been widely used in paleolimnological studies in arid northwestern China. In recent years, however, an increasing number of studies have enriched the environmental significance reflected by the stable carbon isotope geochemistry of lakes;therefore, the interpretation of lake δ13 C variations in paleoenvironmental reconstructions should be carefully evaluated from various aspects. In this paper, previous studies from the past several decades on the lacustrineδ13 C variations in arid northwestern China were reviewed, and the possible mechanisms of the δ13 C variations were discussed.Our study will provide a reference for the application of carbon isotope geochemistry in paleoenvironmental reconstructions.
基金supported by the National Natural Science Foundation of China (Grant Nos. 41530105, 41673073 & 91428308)the Ministry of Science and Technology (Grant No. 2016YFA0601101)+1 种基金the Shenzhen Key Laboratory of Marine Archaea Geo-Omics, Southern University of Science and Technologythe Laboratory for Marine Geology, Qingdao National Laboratory for Marine Science and Technology (Grant No. MGQNLM-TD201810)
文摘The discipline of "Bio-Organic Geochemistry" is a cross research field between biogeochemistry and traditional organic geochemistry, which focuses on geochemical processes related to the biosynthesis of organic molecules(particularly lipids) by(micro) organisms, organic matter production by primary producers, degradation of organic matter by microbial processes recorded by retainable lipid biomarkers, and organic proxies for studies of paleo-climate, paleo-environments, paleoecology and Earth evolution. This field aims to go beyond the traditional petroleum-oriented Organic Geochemistry by integrating with biogeochemical concepts concerned mostly with biomolecules from cellular material such as DNA and lipids. A formal Chinese organization in Bio-Organic Geochemistry was established in 2012 when the first conference was held in Guangzhou. This organization has witnessed rapid growth over the past six years with focused research addressing organic proxies in paleoclimate and paleoenvironmental applications, with particular rapid development in glycerol dialkyl glycerol tetraethers-derived proxies. Most progresses in China so far are made following or paralleling the international trend in biogeochemical studies. Things have begun to change with China's ambitious initiatives in several bio-geo programs such as the Ocean Deep Drilling Program of China, the Microbial Hydrosphere Program, the Deep Carbon Observatory, and the Microbiome Program. Looking forward in the 21 st Century, the growing Chinese research community in Bio-Organic Geochemistry faces grand opportunities and challenges as Chinese scientists propel themselves toward global research frontiers.
基金supported by the National Natural Science Foundation of China(Grant No.41573005)National Basic Research Programme of China(Grant No.2013CB955901)Key Program of the Chinese Academy of Sciences(Grant No.QYZDY-SSWDQC001)
文摘The hydrogen isotopic composition(δD) of n-alkanes in lacustrine sediments is widely used in palaeoenvironmental studies, but the heterogeneous origins and relative contributions of these lipids provide challenges for the interpretation of the increasing dataset as an environment and climatic proxy. We systematically investigated n-alkane δD values from 51 submerged plants(39 Potamogeton, 1 Myriophyllum, and 11 Ruppia), 13 algae(5 Chara, 3 Cladophora, and 5 Spirogyra) and 20 terrestrial plants(10 grasses and 10 shrubs) in and around 15 lakes on the Tibetan Plateau. Our results demonstrate that δD values of C_(29) nalkane are correlated significantly with the lake water δD values both for algae(R^2=0.85, p<0.01, n=9) and submerged plants(R^2=0.90, p<0.01, n=25), indicating that δD values of these algae and submerged plants reflect the δD variation of lake water. We find that apparent hydrogen isotope fractionation factors between individual n-alkanes and water(εa/w) are not constant among different algae and submerged plants, as well as in a single genus under different liminological conditions, indicating that the biosynthesis or environmental conditions(e.g. salinity) may affect their δD values. The δD values of submerged plant Ruppia in the Xiligou Lake(a closed lake) are significant enriched in D than those of terrestrial grasses around the lake(one-way ANOVA,p<0.01), but the algae Chara in the Keluke Lake(an open lake) display similar δD values with grasses around the lake(one-way ANOVA, p=0.826>0.05), suggesting that the n-alkane δD values of the algae and submerged plants record the signal of D enrichment in lake water relative to precipitation only in closed lakes in arid and semi-arid area. For each algae and submerged plant sample, we find uniformed δD values of different chain length n-alkanes, implying that, in combination with other proxies such as Paq and Average Chain Length, the offset between the δD values of different chain length n-alkanes can help determine the source of sedimentary n-alkanes as well as inferring the hydrological characteristics of an ancient lake basin(open vs closed lake).
基金financially supported by the Strategic Priority Research Program of Chinese Academy of Sciences(XDB40000000)the National Natural Science Foundation of China(41672349,40802084)Hong Kong Research Grants Council(17325516)。
基金supported by the Project of Innovative Team of Advanced Optical Manufacturing and Detection(No.2017KCT-08-02)。
文摘The plasma-enhanced chemical vapor deposition(PECVD)technique is well suited for fabricating optical filters with continuously variable refractive index profiles;however,it is not clear how the optical and structural properties of thin films differ when deposited on different substrates.Herein,silicon nitride films were deposited on silicon,fused silica,and glass substrates by PECVD,using silane and ammonia,to investigate the effects of the substrate used on the optical properties and structures of the films.All of the deposited films were amorphous.Further,the types and amounts of Si-centered tetrahedral Si–SivN4-v bonds formed were based upon the substrates used;Si–N4 bonds with higher elemental nitrogen content were formed on Si substrates,which lead to obtaining higher refractive indices,and the Si–SiN3 bonds were mainly formed on glass and fused silica substrates.The refractive indices of the films formed on the different substrates had a maximum difference of0.05(at 550 nm),the refractive index of SiNx films formed on silicon substrates was 1.83,and the refractive indices of films formed on glass were very close to those formed on fused silica.The deposition rates of these SiNx films are similar,and the extinction coefficients of all the films were lower than 10-4.
基金This work was financially supported by the Science and Technology Project of the Department of Science and Technology of Sichuan Province:Key research and development projects(2019YFN0107).
文摘Objectives:Amino acid profiles of whole soybean curds(WSCs)and conventional soybean curds(CSCs)were comparatively studied to 1.,evaluate their nutritional value and 2.,study the suitable soybean material to fabricate WSCs.Materials and Methods:Nine types of soybean materials were selected to make WSCs and CSCs.Protein digestibility-corrected amino acid score(PDCAAS)and principal component analysis were selected to perform the comparative analysis of amino acid profiles of the products.Results:Total contents of amino acids in WSCs and CSCs were 41.24-54.87 mg/g and 27.77-36.82 mg/g.Content ranges of essential amino acids were 13.59-19.38 mg/g and 8.46-11.76 mg/g for WSCs and CSCs.The essential amino acid pattern of WSCs was basically close to amino acid pattern spectrum requirements except valine and sulfur amino acids.As a limiting amino acid,methionine represented less than 0.4 for PDCAAS in all soybean curds except WSCs made from relay-cropping Nandou12 and Nandou25.Conclusions:The overall quality of amino acids in WSCs was higher than that in CSCs,indicating that WSCs indeed exhibited higher nutritional value than CSCs from the viewpoint of amino acid profile.WSCs with the high nutritional value could be made using Nandou25 and relay-cropping Nandou12 as materials.