BACKGROUND Pancreatic cancer remains one of the most lethal malignancies worldwide,with a poor prognosis often attributed to late diagnosis.Understanding the correlation between pathological type and imaging features ...BACKGROUND Pancreatic cancer remains one of the most lethal malignancies worldwide,with a poor prognosis often attributed to late diagnosis.Understanding the correlation between pathological type and imaging features is crucial for early detection and appropriate treatment planning.AIM To retrospectively analyze the relationship between different pathological types of pancreatic cancer and their corresponding imaging features.METHODS We retrospectively analyzed the data of 500 patients diagnosed with pancreatic cancer between January 2010 and December 2020 at our institution.Pathological types were determined by histopathological examination of the surgical spe-cimens or biopsy samples.The imaging features were assessed using computed tomography,magnetic resonance imaging,and endoscopic ultrasound.Statistical analyses were performed to identify significant associations between pathological types and specific imaging characteristics.RESULTS There were 320(64%)cases of pancreatic ductal adenocarcinoma,75(15%)of intraductal papillary mucinous neoplasms,50(10%)of neuroendocrine tumors,and 55(11%)of other rare types.Distinct imaging features were identified in each pathological type.Pancreatic ductal adenocarcinoma typically presents as a hypodense mass with poorly defined borders on computed tomography,whereas intraductal papillary mucinous neoplasms present as characteristic cystic lesions with mural nodules.Neuroendocrine tumors often appear as hypervascular lesions in contrast-enhanced imaging.Statistical analysis revealed significant correlations between specific imaging features and pathological types(P<0.001).CONCLUSION This study demonstrated a strong association between the pathological types of pancreatic cancer and imaging features.These findings can enhance the accuracy of noninvasive diagnosis and guide personalized treatment approaches.展开更多
Globally,hyperuricemia is a growing health,social,and economic problem which could cause gout,chronic kidney diseases and other diseases.There are increasing evidences that a sensible diet makes sense to reduce the ri...Globally,hyperuricemia is a growing health,social,and economic problem which could cause gout,chronic kidney diseases and other diseases.There are increasing evidences that a sensible diet makes sense to reduce the risk of hyperuricemia.This review aims to explore the metabolic mechanism of dietary factors and effects of dietary types associated with hyperuricemia.Recommendations for dietary modification to prevent hyperuricemia are as following:decreasing intake of animal organs,seafood,sugar-sweetened,and alcohol beverages is essential;choosing water or unsweetened tea and coffee instead of sweetened beverages is beneficial;and increasing intake of vegetables,reduced-fat dairy products,foods containing fiber,micronutrients and unsaturated fatty acids is helpful.In addition,consumption of fruits and legumes in moderation is advantageous,and low-fructose of fruits and low-purine of non-soy beans are recommended.Moreover,personalized diet needs to be emphasized for hyperuricemic patients accompanied with diverse metabolic diseases.展开更多
Asian rice comprises two major subspecies:Xian(X)and Geng(G),and the diverged resistance genes(R)have provided a foundation for breeding improved cultivars to control rice blast disease.After conducting two-phase alle...Asian rice comprises two major subspecies:Xian(X)and Geng(G),and the diverged resistance genes(R)have provided a foundation for breeding improved cultivars to control rice blast disease.After conducting two-phase allele mining using six updated FNP marker systems,the functional haplotypes at Pit,Pib,and Pi63 strictly diverged into the X-populations and were defined as X-R loci,while those at Pi54,Pi37,and Pi36 into the G-populations as G-R loci.The genic diversity at the three X-R loci(16 alleles)was twofold higher than that at the three G-R loci(8 alleles),and the allelic diversity in the Southern region(21 alleles)was nearly double that in the Northeastern region(11 alleles).Both observations reflect a significant difference in genetic diversity between X-and G-populations,and indicate that the effective R-genes mainly originated from X-subspecies.Based on the allelic structures characterized by a set of 10 parameters,8 and 16 alleles were respectively recognized as favorable and promising ones for the regional breeding programs.The genotypic structures of the two regional populations were almost different,indicating that the diverged alleles have been further assembled into two series of regional genotypes through long-term breeding programs,despite the presence of one-third of region-common alleles.The genotypic diversity in the Southern region(55 genotypes)was nearly twice as high as that in the Northeastern region(28),which perfectly reflects the aforementioned differences in both genic and allelic diversities.After analyzing the genotypic structures using a set of 13 parameters,4 and 23 genotypes,respectively,can be recommended as the favorable and promising ones for the regional breeding programs.The case study serves as a concrete sample of how to identify the favorable and promising alleles and genotypes,and beneficial parents based their comprehensive population structures for gene-designed breeding.展开更多
Sintered silver nanoparticles(AgNPs)arewidely used in high-power electronics due to their exceptional properties.However,the material reliability is significantly affected by various microscopic defects.In this work,t...Sintered silver nanoparticles(AgNPs)arewidely used in high-power electronics due to their exceptional properties.However,the material reliability is significantly affected by various microscopic defects.In this work,the three primary micro-defect types at potential stress concentrations in sintered AgNPs are identified,categorized,and quantified.Molecular dynamics(MD)simulations are employed to observe the failure evolution of different microscopic defects.The dominant mechanisms responsible for this evolution are dislocation nucleation and dislocation motion.At the same time,this paper clarifies the quantitative relationship between the tensile strain amount and the failure mechanism transitions of the three defect types by defining key strain points.The impact of defect types on the failure process is also discussed.Furthermore,traction-separation curves extracted from microscopic defect evolutions serve as a bridge to connect the macro-scale model.The validity of the crack propagation model is confirmed through tensile tests.Finally,we thoroughly analyze how micro-defect types influence macro-crack propagation and attempt to find supporting evidence from the MD model.Our findings provide a multi-perspective reference for the reliability analysis of sintered AgNPs.展开更多
In generator design field,waveform total harmonic distortion(THD)and telephone harmonic factor(THF)are parameters commonly used to measure the impact of generator no-load voltage harmonics on the power communication q...In generator design field,waveform total harmonic distortion(THD)and telephone harmonic factor(THF)are parameters commonly used to measure the impact of generator no-load voltage harmonics on the power communication quality.Tubular hydrogenerators are considered the optimal generator for exploiting low-head,high-flow hydro resources,and they have seen increasingly widespread application in China's power systems recent years.However,owing to the compact and constrained internal space of such generators,their internal magnetic-field harmonics are pronounced.Therefore,accurate calculation of their THD and THF is crucial during the analysis and design stages to ensure the quality of power communication.Especially in the electromagnetic field finite element modeling analysis of such generators,the type and order of the finite element meshes may have a significant impact on the THD and THF calculation results,which warrants in-depth research.To address this,this study takes a real 34 MW large tubular hydrogenerator as an example,and establishes its electromagnetic field finite element model under no-load conditions.Two types of meshes,five mesh densities,and two mesh orders are analyzed to reveal the effect of electromagnetic field finite element mesh types and orders on the calculation results of THD and THF for such generators.展开更多
BACKGROUND Nutrition recommendations in patients with type 2 diabetes mellitus(T2DM)are to consume rye or integral bread instead of white bread.A positive effect on glucoregulation has been achieved by enriching food ...BACKGROUND Nutrition recommendations in patients with type 2 diabetes mellitus(T2DM)are to consume rye or integral bread instead of white bread.A positive effect on glucoregulation has been achieved by enriching food with various biologically active substances of herbal origin,so we formulated an herbal mixture that can be used as a supplement for a special type of bread(STB)to achieve better effects on postprandial glucose and insulin levels in patients with T2DM.AIM To compare organoleptic characteristics and effects of two types of bread on postprandial glucose and insulin levels in T2DM patients.METHODS This trial included 97 patients with T2DM.A parallel group of 16 healthy subjects was also investigated.All participants were given 50 g of rye bread and the same amount of a STB with an herbal mixture on 2 consecutive days.Postprandial blood glucose and insulin levels were compared at the 30^(th),60^(th),90^(th) and 120th min.A questionnaire was used for subjective estimation of the organoleptic and satiety features of the two types of bread.RESULTS Compared to patients who consumed rye bread,significantly lower postprandial blood glucose and insulin concentrations were found in T2DM patients who consumed STB.No relevant differences were found among the healthy subjects.Subjectively estimated organoleptic and satiety characteristics are better for STB than for rye bread.CONCLUSION STB have better effects than rye bread on postprandial glucoregulation in T2DM patients.Subjectively estimated organoleptic and satiety characteristics are better for STB than for rye bread.Therefore,STB can be recommended for nutrition in T2DM patients.展开更多
Habanero pepper(Capsicum chinense Jacq.)is a crop of economic relevance in the Peninsula of Yucatan.Its fruits have a high level of capsaicinoids compared to peppers grown in other regions of the world,which gives the...Habanero pepper(Capsicum chinense Jacq.)is a crop of economic relevance in the Peninsula of Yucatan.Its fruits have a high level of capsaicinoids compared to peppers grown in other regions of the world,which gives them industrial importance.Soil is an important factor that affects pepper development,nutritional quality,and capsaicinoid content.However,the effect of soil type on fruit development and capsaicinoid metabolism has been little understood.This work aimed to compare the effect of soils with contrasting characteristics,black soil(BS)and red soil(RS),on the expression of genes related to the development of fruits,and capsaicinoid synthesis using a transcriptomic analysis of the habanero pepper fruits.Plants growing in RS had bigger fruits and higher expression of genes related to floral development,fruit abscission,and softening which suggests that RS stimulates fruit development from early stages until maturation stages.Fruits from plants growing in BS had enrichment in metabolic pathways related to growth,sugars,and photosynthesis.Besides,these fruits had higher capsaicinoid accumulation at 25 days post-anthesis,and higher expression of genes related to the branched-chain amino acids metabolism(ketol-acid reductisomerase KARI),pentose phosphate pathway and production of NADPH(glucose-6-phosphate-1-dehydrogenase G6PDH),and proteasome and vesicular traffic in cells(26S proteasome regulatory subunit T4 RPT4),which suggest that BS is better in the early stimulation of pathways related to the nutritional quality and capsaicinoid metabolism in the fruits.展开更多
In order to assess the responses of different skin types stimulated by tape stripping,after which two kinds of brand cosmetics of cream and hydrogel,were separately applied to evaluate the individual soothing effect o...In order to assess the responses of different skin types stimulated by tape stripping,after which two kinds of brand cosmetics of cream and hydrogel,were separately applied to evaluate the individual soothing effect of the product on different skin types.A total of 30 volunteers aged 18~65 years were recruited,which were divided into four groups(oily,dry,normal and combined)according to the self-oiling ability of facial and T zones.Four 3 cm×3 cm of skins on inner forearm of each volunteer were chosen and randomly marked as blank,negative control,soothing cream and soothing gel.The blank area was kept untreated,and the remaining areas were tape-stripped by 10 times(Transparent universal 1527C-1,3M China Co.,Ltd.,)to disrupt the skin corneum and induce erythema.Images,erythema index(EI)and transcutaneous water loss rate(TEWL)of the marked skin areas before and 5 min after tape-stripping were taken to assess the distinct responses of different skin type to the taping treatment;Ten minutes after tape-stripping,The soothing products were applied to the test area,the skin images,EI and TEWL at 20 min and 50 min(corresponding to 30 min and 60 min after tape-stripping,respectively)were measured after cosmetics application to compare and evaluate the soothing effects of cream and hydrogel on different skin types.Results showed that different skin displayed diverse reactions to the tape-stripping,and the oily skin was more sensitive with longer duration of erythema than other skin types.After the application of soothing products,both cream and hydrogel could relieve skin erythema,while the soothing effects are dependent both on skin types and the cosmetic base materials:Hydrogel has a better efficacy in alleviating erythema and TEWL of dry skin,while the cream was more effective on normal,oily and combined skin types.The results suggest that the modelling method for soothing evaluation should consider the skin types of the volunteers,and the cosmetics of different base materials might have the target skin types.展开更多
The Congolese population is organised into households, which are thus headed by a chief who ensures the social well-being, development and integration into working life of the individuals in his charge. This study exa...The Congolese population is organised into households, which are thus headed by a chief who ensures the social well-being, development and integration into working life of the individuals in his charge. This study examines the functional principles of new housing design as an instrument for transforming the (current) failing economy into a strong and resilient one. Accordingly, a literature review of the practice of designing and building housing in human settlements in the Congo revealed the state of the art on this subject. An analysis of the existing housing stock from a demographic, social and economic point of view made it possible to identify the most common household sizes and numbers, as well as the lifestyle processes that determine the need for developed space. To this end, the experimental method was used to propose configuration plans for various new types of dwelling. To this end, the study highlighted the link between people’s standard of living and the effectiveness of their involvement in the local economy. To achieve the aims of the National Development Plan (NDP), particular attention must be paid to solving the housing problem. The existing housing stock actively contributes to the problems associated with unemployment and insecurity. Functional principles for the design of new types of housing have been developed. Four model types are proposed in line with the demographic structure of the population, their socio-economic characteristics and their lifestyle.展开更多
Objective:To analyze the clinical and laboratory indices of patients with lupus nephritis(LN)of different pathological types and explore the related factors of LN pathological classification,it is helpful to grasp the...Objective:To analyze the clinical and laboratory indices of patients with lupus nephritis(LN)of different pathological types and explore the related factors of LN pathological classification,it is helpful to grasp the timing of renal biopsy.Methods:The clinical manifestations,laboratory parameters and renal pathological types of LN patients in recent 20 years were analyzed retrospectively by SPSS 26.0 software.Results:In this study,the first three pathological types were V,IV,V+IV;latent nephritis was common in type II and V;nephritic syndrome was common in type V;nephrotic syndrome was common in type V+IV;chronic renal insufficiency group was mostly type IV;pathological types were correlated with serum creatinine,C3,albumin and erythrocyte sedimentation rate(r=0.315,P<0.001),and serum creatinine was moderately correlated(r=0.315,P<0.001);AI,CI and SLEDAI scores were significantly different among LN patients of different pathological types.Conclusion:LN is closely related to clinical pathology,clinical manifestations,comprehensive analysis of laboratory indicators and SLEDAI score to make a preliminary prediction of LN pathological type,help to initially assess the severity of pathology,improve the timing of renal biopsy implementation,optimize the timing of treatment.展开更多
Tree mortality significantly influences forest structure and function,yet our understanding of its dynamic patterns among a range of tree sizes and among different plant functional types(PFTs)remains incomplete.This s...Tree mortality significantly influences forest structure and function,yet our understanding of its dynamic patterns among a range of tree sizes and among different plant functional types(PFTs)remains incomplete.This study analysed size-dependent tree mortality in a temperate forest,encompassing 46 tree species and 32,565 individuals across different PFTs(i.e.,evergreen conifer vs.deciduous broadleaf species,shade-tolerant vs.shade-intolerant species).By employing all-subset regression procedures and logistic generalized linear mixed-effects models,we identified distinct mortality patterns influenced by biotic and abiotic factors.Our results showed a stable mortality patte rn in eve rgreen conifer species,contrasted by a declining pattern in deciduous broadleaf and shadetolerant,as well as shade-intolerant species,across size classes.The contribution to tree mortality of evergreen conifer species shifted from abiotic to biotic factors with increasing size,while the mortality of deciduous broadleaf species was mainly influenced by biotic factors,such as initial diameter at breast height(DBH)and conspecific negative density.For shade-tolerant species,the mortality of small individuals was mainly determined by initial DBH and conspecific negative density dependence,whereas the mortality of large individuals was subjected to the combined effect of biotic(competition from neighbours)and abiotic factors(i.e.,convexity and pH).As for shade-intolerant species,competition from neighbours was found to be the main driver of tree mortality throughout their growth stages.Thus,these insights enhance our understanding of forest dynamics by revealing the size-dependent and PFT-specific tree mortality patterns,which may inform strategies for maintaining forest diversity and resilience in temperate forest ecosystems.展开更多
Identification of reservoir types in deep carbonates has always been a great challenge due to complex logging responses caused by the heterogeneous scale and distribution of storage spaces.Traditional cross-plot analy...Identification of reservoir types in deep carbonates has always been a great challenge due to complex logging responses caused by the heterogeneous scale and distribution of storage spaces.Traditional cross-plot analysis and empirical formula methods for identifying reservoir types using geophysical logging data have high uncertainty and low efficiency,which cannot accurately reflect the nonlinear relationship between reservoir types and logging data.Recently,the kernel Fisher discriminant analysis(KFD),a kernel-based machine learning technique,attracts attention in many fields because of its strong nonlinear processing ability.However,the overall performance of KFD model may be limited as a single kernel function cannot simultaneously extrapolate and interpolate well,especially for highly complex data cases.To address this issue,in this study,a mixed kernel Fisher discriminant analysis(MKFD)model was established and applied to identify reservoir types of the deep Sinian carbonates in central Sichuan Basin,China.The MKFD model was trained and tested with 453 datasets from 7 coring wells,utilizing GR,CAL,DEN,AC,CNL and RT logs as input variables.The particle swarm optimization(PSO)was adopted for hyper-parameter optimization of MKFD model.To evaluate the model performance,prediction results of MKFD were compared with those of basic-kernel based KFD,RF and SVM models.Subsequently,the built MKFD model was applied in a blind well test,and a variable importance analysis was conducted.The comparison and blind test results demonstrated that MKFD outperformed traditional KFD,RF and SVM in the identification of reservoir types,which provided higher accuracy and stronger generalization.The MKFD can therefore be a reliable method for identifying reservoir types of deep carbonates.展开更多
The cloud type product 2B-CLDCLASS-LIDAR based on CloudSat and CALIPSO from June 2006 to May 2017 is used to examine the temporal and spatial distribution characteristics and interannual variability of eight cloud typ...The cloud type product 2B-CLDCLASS-LIDAR based on CloudSat and CALIPSO from June 2006 to May 2017 is used to examine the temporal and spatial distribution characteristics and interannual variability of eight cloud types(high cloud, altostratus, altocumulus, stratus, stratocumulus, cumulus, nimbostratus, and deep convection) and three phases(ice,mixed, and water) in the Arctic. Possible reasons for the observed interannual variability are also discussed. The main conclusions are as follows:(1) More water clouds occur on the Atlantic side, and more ice clouds occur over continents.(2)The average spatial and seasonal distributions of cloud types show three patterns: high clouds and most cumuliform clouds are concentrated in low-latitude locations and peak in summer;altostratus and nimbostratus are concentrated over and around continents and are less abundant in summer;stratocumulus and stratus are concentrated near the inner Arctic and peak during spring and autumn.(3) Regional averaged interannual frequencies of ice clouds and altostratus clouds significantly decrease, while those of water clouds, altocumulus, and cumulus clouds increase significantly.(4) Significant features of the linear trends of cloud frequencies are mainly located over ocean areas.(5) The monthly water cloud frequency anomalies are positively correlated with air temperature in most of the troposphere, while those for ice clouds are negatively correlated.(6) The decrease in altostratus clouds is associated with the weakening of the Arctic front due to Arctic warming, while increased water vapor transport into the Arctic and higher atmospheric instability lead to more cumulus and altocumulus clouds.展开更多
The Ground Cover Rice Production System(GCRPS)has considerable potential for securing rice production in hilly areas.However,its impact on yields and nitrogen(N)fates remains uncertain under varying rainfall condition...The Ground Cover Rice Production System(GCRPS)has considerable potential for securing rice production in hilly areas.However,its impact on yields and nitrogen(N)fates remains uncertain under varying rainfall conditions.A two-year field experiment(2021–2022)was conducted in Ziyang,Sichuan Province,located in the hilly areas of Southwest China.The experiment included two cultivation methods:conventional flooding paddy(Paddy,W1)and GCRPS(W2).These methods were combined with three N management practices:N1(no-N fertilizer),N2(135 kg/hm^(2)urea as a base fertilizer in both W1 and W2),and N3(135 kg/hm^(2)urea with split application for W1 and 67.5 kg/hm^(2)urea and chicken manure separately for W2).The WHCNS(Soil Water Heat Carbon Nitrogen Simulator)model was calibrated and validated to simulate ponding water depth,soil water storage,soil mineral N content,leaf area index,aboveground dry matter,crop N uptake,and rice yield.Subsequently,this model was used to simulate the responses of rice yield and N fates to GCRPS under different types of precipitation years using meteorological data from 1980 to 2018.The results indicated that the WHCNS model performed well in simulating crop growth and N fates for both Paddy and GCRPS.Compared with Paddy,GCRPS reduced N leaching(35.1%–54.9%),ammonia volatilization(0.7%–13.6%),N runoff(71.1%–83.5%),denitrification(3.8%–6.7%),and total N loss(33.8%–56.9%)for all precipitation year types.However,GCRPS reduced crop N uptake and yield during wet years,while increasing crop N uptake and yield during dry and normal years.Fertilizer application reduced the stability and sustainability of rice yield in wet years,but increased the stability and sustainability of rice yield in dry and normal years.In conclusion,GCRPS is more suitable for normal and dry years in the study region,leading to increased rice yield and reduced N loss.展开更多
Soil soluble organic matter is an important component in the study of carbon and nitrogen cycling in terrestrial ecosystems. Soil microorganisms, as soil decomposers, participate in soil biogeochemical processes and p...Soil soluble organic matter is an important component in the study of carbon and nitrogen cycling in terrestrial ecosystems. Soil microorganisms, as soil decomposers, participate in soil biogeochemical processes and play an important role in maintaining the balance of soil ecosystems. As a typical subtropical regional unit, Queensland, Australia, is a relatively concentrated distribution area of forests in Australia. It is very sensitive to climate change and plays an important role in Australian climate and even global climate change. Its unique natural environment and ecosystem occupy a special position in the world. However, the knowledge of available carbon and nitrogen pool and microbial activity in forest soil is still very limited. Pinus elliottii, Araucaria cunninghamii and Agathis australis are the three most important forest types in southern Queensland, Australia. In our research, the function and structural diversity of soil microbial communities of these three forest types were studied using biochemical and molecular biological methods, and the effective carbon and nitrogen pools of soil of different forest types and related microbial processes were discussed, which has important theoretical guiding significance for further research on the structure and function of soil ecosystem. The number of PLFAs in the soil of P. elliottii was 45, the number of PLFAs in the soil of Araucaria cunninghamii and Agathis australis was 39 and 35, respectively. The number and content of PLFAs monomer in P. elliottii were higher than those in the other two kinds of forest soil.展开更多
[Objective] The research was aimed to study the dynamics of slope runoff and soil erosion in different forest types in karst depression.[Method] Precipitation observation sites at the bottom of karst depression and ru...[Objective] The research was aimed to study the dynamics of slope runoff and soil erosion in different forest types in karst depression.[Method] Precipitation observation sites at the bottom of karst depression and runoff observation sites in different forest types were established to monitor regularly the main indices changes of runoff and soil erosion at fixed position in 4 years.[Result] The surface runoff of different forest types appeared singer peak from February to November,with lowest valley from June to July.The runoff coefficient appeared double peaks from February to May and from July to September.The changing coefficient of runoff appeared three peaks from March to April,from July to August and from September to November.The silt concentration appeared one peak from March to May and The erosion modulus appeared double peaks from March to May and from June to August.Runoff showed annually reduced trend with the growth of forests and the development of vegetation layer＇s structure.There was a positive correlation between the runoff and its silt concentration in different forest types.Precipitation and evaporation had notable positive correlation with the runoff,and similar correlation but not marked with silt concentration.The fitting analysis results of surface runoff and erosion modulus showed that rocky desertification intensified the unevenness of surface runoff and increased the surface runoff and erosion modulus.The penetrability of surface soil in new planted forest was lower than that in young forest,and that in surface soil of different forest types was higher than in bottom soil.[Conclusion] The research provided theoretical basis for the biological management technologies of water and soil conservation and the control of karst rocky desertification in karst regions.展开更多
[Objective] Through the investigation of weeds in Coffea arabica orchads in NuJiang River basin, this study aimed to provide scientific guidance for the weed control and improving the ecological and economic benefits ...[Objective] Through the investigation of weeds in Coffea arabica orchads in NuJiang River basin, this study aimed to provide scientific guidance for the weed control and improving the ecological and economic benefits of the plantation of Cof- fea arabica. [Method] The types of weeds and the characteristics of weed occur- rence in Coffea arabica orchads in Nujiang River basin were investigated from July to August in 2012. [Result] The results showed that there were 69 types of weeds belonging to 21 families in Coffea arabica orchads. The predominant harmful types were shown as follows： Commelina nudiflora L. ＋ Leptochloa chinensis, Cyperus ro- tundus L. ＋ Bidens pilosa L. ＋ Eleusine indica, Imperata cylindrical ＋ Ageratum conyzoides L. ＋ Eupatorium odoratum L., Ageratum conyzoides L. ＋ Digitaria san- guinalis （L.） Scop. The preponderant weeds consisted mainly of 10 species, namely, Cyperus rotundus L., Commelina nudiflora L., Leptochloa chinensis, Digitaria san- guinalis （L.） Scop, Imperata cylindrical, Bidens pilosa L., Ageratum conyzoides L, E- upatorium odoratum L., Eleusine indica and Chenopodium serotinum L. [Conclusion] The result from this study is of great significance for the plantation of Coffea arabica in Nujiang River basin, as well as the control of weeds.展开更多
In the research, pot experiment and field testing were conducted to study the effect of different crops, soil types, and irrigation modes on biogas slurry diges- tions. The results showed that when silage maize, sweet...In the research, pot experiment and field testing were conducted to study the effect of different crops, soil types, and irrigation modes on biogas slurry diges- tions. The results showed that when silage maize, sweet sorghum and Chinese cabbage were planted in purple soils, the quantities of digested biogas slurry were of 57, 157.5, and 34.5 t/hm2, respectively, while the quantities of digested biogas slurry were 70.5, 157.5 and 40.5 t/hm2 in yellow soils. Besides, the digested biogas slurries reached 36 and 27 t/hm2 as per flood irrigation and sprinkling irrigation when Chinese cabbages were planted in yellow soils. The research indicated crop variety, soil type, and irrigation method all have effects on farmland digestion of biogas slurry.展开更多
[Objective] The aim was to reveal changes of soil organic matter fraction and their corresponding carbon management indexes as affected by different land use types.[Method]Soil organic carbon,active soil organic carbo...[Objective] The aim was to reveal changes of soil organic matter fraction and their corresponding carbon management indexes as affected by different land use types.[Method]Soil organic carbon,active soil organic carbon and soil carbon management index（CMI）of different land use types in Guilin Maocun karst area were studied.Sampling with field investigation and laboratory testing was carried out.Heavy potassium chromate method was adopted to determine soil organic matter.333 mmol/L KMnO4 oxidation method was used to determine active organic carbon.[Result]With active soil organic matter increasing,the differences of CMI between different land use types were bigger.The CMI value of different land uses was shrubforest paddy fielddry farmland.The statistical analysis showed that labile organic matter was related with major soil properties at a significant level.[Conclusion]Labile organic matter could be used to reveal the influence of different land use types on soil organic matter and carbon management index in karst area.展开更多
[Objective] The aim was to study influences of different land use ways on soil qualities in plateau karst depression.[Method] Different land use types were divided by topographic map of 1∶10 000 scales and soil prope...[Objective] The aim was to study influences of different land use ways on soil qualities in plateau karst depression.[Method] Different land use types were divided by topographic map of 1∶10 000 scales and soil properties of physics and chemistry were analyzed.[Result] The results showed that the variation trend of soil depth(A+B stratum)was slope plough(include returning farm to forest)land>natural forest land>planted forest land>shrub forest land,and relative indexes changing regularities of soil...展开更多
文摘BACKGROUND Pancreatic cancer remains one of the most lethal malignancies worldwide,with a poor prognosis often attributed to late diagnosis.Understanding the correlation between pathological type and imaging features is crucial for early detection and appropriate treatment planning.AIM To retrospectively analyze the relationship between different pathological types of pancreatic cancer and their corresponding imaging features.METHODS We retrospectively analyzed the data of 500 patients diagnosed with pancreatic cancer between January 2010 and December 2020 at our institution.Pathological types were determined by histopathological examination of the surgical spe-cimens or biopsy samples.The imaging features were assessed using computed tomography,magnetic resonance imaging,and endoscopic ultrasound.Statistical analyses were performed to identify significant associations between pathological types and specific imaging characteristics.RESULTS There were 320(64%)cases of pancreatic ductal adenocarcinoma,75(15%)of intraductal papillary mucinous neoplasms,50(10%)of neuroendocrine tumors,and 55(11%)of other rare types.Distinct imaging features were identified in each pathological type.Pancreatic ductal adenocarcinoma typically presents as a hypodense mass with poorly defined borders on computed tomography,whereas intraductal papillary mucinous neoplasms present as characteristic cystic lesions with mural nodules.Neuroendocrine tumors often appear as hypervascular lesions in contrast-enhanced imaging.Statistical analysis revealed significant correlations between specific imaging features and pathological types(P<0.001).CONCLUSION This study demonstrated a strong association between the pathological types of pancreatic cancer and imaging features.These findings can enhance the accuracy of noninvasive diagnosis and guide personalized treatment approaches.
基金supported by the National Natural Science Foundation of China(No.32122069)Beijing Outstanding Young Scientist Program(No.BJJWZYJH01201910011025)China Postdoctoral Science Foundation(No.2023M730134)。
文摘Globally,hyperuricemia is a growing health,social,and economic problem which could cause gout,chronic kidney diseases and other diseases.There are increasing evidences that a sensible diet makes sense to reduce the risk of hyperuricemia.This review aims to explore the metabolic mechanism of dietary factors and effects of dietary types associated with hyperuricemia.Recommendations for dietary modification to prevent hyperuricemia are as following:decreasing intake of animal organs,seafood,sugar-sweetened,and alcohol beverages is essential;choosing water or unsweetened tea and coffee instead of sweetened beverages is beneficial;and increasing intake of vegetables,reduced-fat dairy products,foods containing fiber,micronutrients and unsaturated fatty acids is helpful.In addition,consumption of fruits and legumes in moderation is advantageous,and low-fructose of fruits and low-purine of non-soy beans are recommended.Moreover,personalized diet needs to be emphasized for hyperuricemic patients accompanied with diverse metabolic diseases.
基金funded by grants from the National Key R&D Project(2023YFD1400201-02,2023YFD1400203-02)the National Natural Science Foundation of China(31870137)+1 种基金the National Transgenic Research Project(2015ZX08001-002)the Key R&D Project of Guangdong Province(2022B0202060005).
文摘Asian rice comprises two major subspecies:Xian(X)and Geng(G),and the diverged resistance genes(R)have provided a foundation for breeding improved cultivars to control rice blast disease.After conducting two-phase allele mining using six updated FNP marker systems,the functional haplotypes at Pit,Pib,and Pi63 strictly diverged into the X-populations and were defined as X-R loci,while those at Pi54,Pi37,and Pi36 into the G-populations as G-R loci.The genic diversity at the three X-R loci(16 alleles)was twofold higher than that at the three G-R loci(8 alleles),and the allelic diversity in the Southern region(21 alleles)was nearly double that in the Northeastern region(11 alleles).Both observations reflect a significant difference in genetic diversity between X-and G-populations,and indicate that the effective R-genes mainly originated from X-subspecies.Based on the allelic structures characterized by a set of 10 parameters,8 and 16 alleles were respectively recognized as favorable and promising ones for the regional breeding programs.The genotypic structures of the two regional populations were almost different,indicating that the diverged alleles have been further assembled into two series of regional genotypes through long-term breeding programs,despite the presence of one-third of region-common alleles.The genotypic diversity in the Southern region(55 genotypes)was nearly twice as high as that in the Northeastern region(28),which perfectly reflects the aforementioned differences in both genic and allelic diversities.After analyzing the genotypic structures using a set of 13 parameters,4 and 23 genotypes,respectively,can be recommended as the favorable and promising ones for the regional breeding programs.The case study serves as a concrete sample of how to identify the favorable and promising alleles and genotypes,and beneficial parents based their comprehensive population structures for gene-designed breeding.
基金supported by the China Scholarship Council (CSC) (No.202206020149)the Academic Excellence Foundation of BUAA for PhD Students,the Funding Project of Science and Technology on Reliability and Environmental Engineering Laboratory (No.6142004210106).
文摘Sintered silver nanoparticles(AgNPs)arewidely used in high-power electronics due to their exceptional properties.However,the material reliability is significantly affected by various microscopic defects.In this work,the three primary micro-defect types at potential stress concentrations in sintered AgNPs are identified,categorized,and quantified.Molecular dynamics(MD)simulations are employed to observe the failure evolution of different microscopic defects.The dominant mechanisms responsible for this evolution are dislocation nucleation and dislocation motion.At the same time,this paper clarifies the quantitative relationship between the tensile strain amount and the failure mechanism transitions of the three defect types by defining key strain points.The impact of defect types on the failure process is also discussed.Furthermore,traction-separation curves extracted from microscopic defect evolutions serve as a bridge to connect the macro-scale model.The validity of the crack propagation model is confirmed through tensile tests.Finally,we thoroughly analyze how micro-defect types influence macro-crack propagation and attempt to find supporting evidence from the MD model.Our findings provide a multi-perspective reference for the reliability analysis of sintered AgNPs.
基金sponsored by the National Natural Science Foundation,Youth Foundation of China,Grant/Award Number:51607146Sichuan Natural Sciences Fund,Grant/Award Number:2023NSFSC0295。
文摘In generator design field,waveform total harmonic distortion(THD)and telephone harmonic factor(THF)are parameters commonly used to measure the impact of generator no-load voltage harmonics on the power communication quality.Tubular hydrogenerators are considered the optimal generator for exploiting low-head,high-flow hydro resources,and they have seen increasingly widespread application in China's power systems recent years.However,owing to the compact and constrained internal space of such generators,their internal magnetic-field harmonics are pronounced.Therefore,accurate calculation of their THD and THF is crucial during the analysis and design stages to ensure the quality of power communication.Especially in the electromagnetic field finite element modeling analysis of such generators,the type and order of the finite element meshes may have a significant impact on the THD and THF calculation results,which warrants in-depth research.To address this,this study takes a real 34 MW large tubular hydrogenerator as an example,and establishes its electromagnetic field finite element model under no-load conditions.Two types of meshes,five mesh densities,and two mesh orders are analyzed to reveal the effect of electromagnetic field finite element mesh types and orders on the calculation results of THD and THF for such generators.
文摘BACKGROUND Nutrition recommendations in patients with type 2 diabetes mellitus(T2DM)are to consume rye or integral bread instead of white bread.A positive effect on glucoregulation has been achieved by enriching food with various biologically active substances of herbal origin,so we formulated an herbal mixture that can be used as a supplement for a special type of bread(STB)to achieve better effects on postprandial glucose and insulin levels in patients with T2DM.AIM To compare organoleptic characteristics and effects of two types of bread on postprandial glucose and insulin levels in T2DM patients.METHODS This trial included 97 patients with T2DM.A parallel group of 16 healthy subjects was also investigated.All participants were given 50 g of rye bread and the same amount of a STB with an herbal mixture on 2 consecutive days.Postprandial blood glucose and insulin levels were compared at the 30^(th),60^(th),90^(th) and 120th min.A questionnaire was used for subjective estimation of the organoleptic and satiety features of the two types of bread.RESULTS Compared to patients who consumed rye bread,significantly lower postprandial blood glucose and insulin concentrations were found in T2DM patients who consumed STB.No relevant differences were found among the healthy subjects.Subjectively estimated organoleptic and satiety characteristics are better for STB than for rye bread.CONCLUSION STB have better effects than rye bread on postprandial glucoregulation in T2DM patients.Subjectively estimated organoleptic and satiety characteristics are better for STB than for rye bread.Therefore,STB can be recommended for nutrition in T2DM patients.
文摘Habanero pepper(Capsicum chinense Jacq.)is a crop of economic relevance in the Peninsula of Yucatan.Its fruits have a high level of capsaicinoids compared to peppers grown in other regions of the world,which gives them industrial importance.Soil is an important factor that affects pepper development,nutritional quality,and capsaicinoid content.However,the effect of soil type on fruit development and capsaicinoid metabolism has been little understood.This work aimed to compare the effect of soils with contrasting characteristics,black soil(BS)and red soil(RS),on the expression of genes related to the development of fruits,and capsaicinoid synthesis using a transcriptomic analysis of the habanero pepper fruits.Plants growing in RS had bigger fruits and higher expression of genes related to floral development,fruit abscission,and softening which suggests that RS stimulates fruit development from early stages until maturation stages.Fruits from plants growing in BS had enrichment in metabolic pathways related to growth,sugars,and photosynthesis.Besides,these fruits had higher capsaicinoid accumulation at 25 days post-anthesis,and higher expression of genes related to the branched-chain amino acids metabolism(ketol-acid reductisomerase KARI),pentose phosphate pathway and production of NADPH(glucose-6-phosphate-1-dehydrogenase G6PDH),and proteasome and vesicular traffic in cells(26S proteasome regulatory subunit T4 RPT4),which suggest that BS is better in the early stimulation of pathways related to the nutritional quality and capsaicinoid metabolism in the fruits.
文摘In order to assess the responses of different skin types stimulated by tape stripping,after which two kinds of brand cosmetics of cream and hydrogel,were separately applied to evaluate the individual soothing effect of the product on different skin types.A total of 30 volunteers aged 18~65 years were recruited,which were divided into four groups(oily,dry,normal and combined)according to the self-oiling ability of facial and T zones.Four 3 cm×3 cm of skins on inner forearm of each volunteer were chosen and randomly marked as blank,negative control,soothing cream and soothing gel.The blank area was kept untreated,and the remaining areas were tape-stripped by 10 times(Transparent universal 1527C-1,3M China Co.,Ltd.,)to disrupt the skin corneum and induce erythema.Images,erythema index(EI)and transcutaneous water loss rate(TEWL)of the marked skin areas before and 5 min after tape-stripping were taken to assess the distinct responses of different skin type to the taping treatment;Ten minutes after tape-stripping,The soothing products were applied to the test area,the skin images,EI and TEWL at 20 min and 50 min(corresponding to 30 min and 60 min after tape-stripping,respectively)were measured after cosmetics application to compare and evaluate the soothing effects of cream and hydrogel on different skin types.Results showed that different skin displayed diverse reactions to the tape-stripping,and the oily skin was more sensitive with longer duration of erythema than other skin types.After the application of soothing products,both cream and hydrogel could relieve skin erythema,while the soothing effects are dependent both on skin types and the cosmetic base materials:Hydrogel has a better efficacy in alleviating erythema and TEWL of dry skin,while the cream was more effective on normal,oily and combined skin types.The results suggest that the modelling method for soothing evaluation should consider the skin types of the volunteers,and the cosmetics of different base materials might have the target skin types.
文摘The Congolese population is organised into households, which are thus headed by a chief who ensures the social well-being, development and integration into working life of the individuals in his charge. This study examines the functional principles of new housing design as an instrument for transforming the (current) failing economy into a strong and resilient one. Accordingly, a literature review of the practice of designing and building housing in human settlements in the Congo revealed the state of the art on this subject. An analysis of the existing housing stock from a demographic, social and economic point of view made it possible to identify the most common household sizes and numbers, as well as the lifestyle processes that determine the need for developed space. To this end, the experimental method was used to propose configuration plans for various new types of dwelling. To this end, the study highlighted the link between people’s standard of living and the effectiveness of their involvement in the local economy. To achieve the aims of the National Development Plan (NDP), particular attention must be paid to solving the housing problem. The existing housing stock actively contributes to the problems associated with unemployment and insecurity. Functional principles for the design of new types of housing have been developed. Four model types are proposed in line with the demographic structure of the population, their socio-economic characteristics and their lifestyle.
基金Shandong Province Medical and Health Science and Technology Development Plan Project(No.202203051068).
文摘Objective:To analyze the clinical and laboratory indices of patients with lupus nephritis(LN)of different pathological types and explore the related factors of LN pathological classification,it is helpful to grasp the timing of renal biopsy.Methods:The clinical manifestations,laboratory parameters and renal pathological types of LN patients in recent 20 years were analyzed retrospectively by SPSS 26.0 software.Results:In this study,the first three pathological types were V,IV,V+IV;latent nephritis was common in type II and V;nephritic syndrome was common in type V;nephrotic syndrome was common in type V+IV;chronic renal insufficiency group was mostly type IV;pathological types were correlated with serum creatinine,C3,albumin and erythrocyte sedimentation rate(r=0.315,P<0.001),and serum creatinine was moderately correlated(r=0.315,P<0.001);AI,CI and SLEDAI scores were significantly different among LN patients of different pathological types.Conclusion:LN is closely related to clinical pathology,clinical manifestations,comprehensive analysis of laboratory indicators and SLEDAI score to make a preliminary prediction of LN pathological type,help to initially assess the severity of pathology,improve the timing of renal biopsy implementation,optimize the timing of treatment.
基金supported by the China Postdoctoral Science Foundation (No.2023M733712)the National Natural Science Foundation of China (No.31971491)。
文摘Tree mortality significantly influences forest structure and function,yet our understanding of its dynamic patterns among a range of tree sizes and among different plant functional types(PFTs)remains incomplete.This study analysed size-dependent tree mortality in a temperate forest,encompassing 46 tree species and 32,565 individuals across different PFTs(i.e.,evergreen conifer vs.deciduous broadleaf species,shade-tolerant vs.shade-intolerant species).By employing all-subset regression procedures and logistic generalized linear mixed-effects models,we identified distinct mortality patterns influenced by biotic and abiotic factors.Our results showed a stable mortality patte rn in eve rgreen conifer species,contrasted by a declining pattern in deciduous broadleaf and shadetolerant,as well as shade-intolerant species,across size classes.The contribution to tree mortality of evergreen conifer species shifted from abiotic to biotic factors with increasing size,while the mortality of deciduous broadleaf species was mainly influenced by biotic factors,such as initial diameter at breast height(DBH)and conspecific negative density.For shade-tolerant species,the mortality of small individuals was mainly determined by initial DBH and conspecific negative density dependence,whereas the mortality of large individuals was subjected to the combined effect of biotic(competition from neighbours)and abiotic factors(i.e.,convexity and pH).As for shade-intolerant species,competition from neighbours was found to be the main driver of tree mortality throughout their growth stages.Thus,these insights enhance our understanding of forest dynamics by revealing the size-dependent and PFT-specific tree mortality patterns,which may inform strategies for maintaining forest diversity and resilience in temperate forest ecosystems.
基金supported by the National Natural Science Foundation of China(No.U21B2062)the Natural Science Foundation of Hubei Province(No.2023AFB307)。
文摘Identification of reservoir types in deep carbonates has always been a great challenge due to complex logging responses caused by the heterogeneous scale and distribution of storage spaces.Traditional cross-plot analysis and empirical formula methods for identifying reservoir types using geophysical logging data have high uncertainty and low efficiency,which cannot accurately reflect the nonlinear relationship between reservoir types and logging data.Recently,the kernel Fisher discriminant analysis(KFD),a kernel-based machine learning technique,attracts attention in many fields because of its strong nonlinear processing ability.However,the overall performance of KFD model may be limited as a single kernel function cannot simultaneously extrapolate and interpolate well,especially for highly complex data cases.To address this issue,in this study,a mixed kernel Fisher discriminant analysis(MKFD)model was established and applied to identify reservoir types of the deep Sinian carbonates in central Sichuan Basin,China.The MKFD model was trained and tested with 453 datasets from 7 coring wells,utilizing GR,CAL,DEN,AC,CNL and RT logs as input variables.The particle swarm optimization(PSO)was adopted for hyper-parameter optimization of MKFD model.To evaluate the model performance,prediction results of MKFD were compared with those of basic-kernel based KFD,RF and SVM models.Subsequently,the built MKFD model was applied in a blind well test,and a variable importance analysis was conducted.The comparison and blind test results demonstrated that MKFD outperformed traditional KFD,RF and SVM in the identification of reservoir types,which provided higher accuracy and stronger generalization.The MKFD can therefore be a reliable method for identifying reservoir types of deep carbonates.
基金supported in part by the National Natural Science Foundation of China (Grant No. 42105127)the Special Research Assistant Project of the Chinese Academy of Sciencesthe National Key Research and Development Plans of China (Grant Nos. 2019YFC1510304 and 2016YFE0201900-02)。
文摘The cloud type product 2B-CLDCLASS-LIDAR based on CloudSat and CALIPSO from June 2006 to May 2017 is used to examine the temporal and spatial distribution characteristics and interannual variability of eight cloud types(high cloud, altostratus, altocumulus, stratus, stratocumulus, cumulus, nimbostratus, and deep convection) and three phases(ice,mixed, and water) in the Arctic. Possible reasons for the observed interannual variability are also discussed. The main conclusions are as follows:(1) More water clouds occur on the Atlantic side, and more ice clouds occur over continents.(2)The average spatial and seasonal distributions of cloud types show three patterns: high clouds and most cumuliform clouds are concentrated in low-latitude locations and peak in summer;altostratus and nimbostratus are concentrated over and around continents and are less abundant in summer;stratocumulus and stratus are concentrated near the inner Arctic and peak during spring and autumn.(3) Regional averaged interannual frequencies of ice clouds and altostratus clouds significantly decrease, while those of water clouds, altocumulus, and cumulus clouds increase significantly.(4) Significant features of the linear trends of cloud frequencies are mainly located over ocean areas.(5) The monthly water cloud frequency anomalies are positively correlated with air temperature in most of the troposphere, while those for ice clouds are negatively correlated.(6) The decrease in altostratus clouds is associated with the weakening of the Arctic front due to Arctic warming, while increased water vapor transport into the Arctic and higher atmospheric instability lead to more cumulus and altocumulus clouds.
基金supported by the National Natural Science Foundation of China (Grant No.41977008)the 2115 Talent Development Program of China Agricultural University (Grant No.1191-00109011)。
文摘The Ground Cover Rice Production System(GCRPS)has considerable potential for securing rice production in hilly areas.However,its impact on yields and nitrogen(N)fates remains uncertain under varying rainfall conditions.A two-year field experiment(2021–2022)was conducted in Ziyang,Sichuan Province,located in the hilly areas of Southwest China.The experiment included two cultivation methods:conventional flooding paddy(Paddy,W1)and GCRPS(W2).These methods were combined with three N management practices:N1(no-N fertilizer),N2(135 kg/hm^(2)urea as a base fertilizer in both W1 and W2),and N3(135 kg/hm^(2)urea with split application for W1 and 67.5 kg/hm^(2)urea and chicken manure separately for W2).The WHCNS(Soil Water Heat Carbon Nitrogen Simulator)model was calibrated and validated to simulate ponding water depth,soil water storage,soil mineral N content,leaf area index,aboveground dry matter,crop N uptake,and rice yield.Subsequently,this model was used to simulate the responses of rice yield and N fates to GCRPS under different types of precipitation years using meteorological data from 1980 to 2018.The results indicated that the WHCNS model performed well in simulating crop growth and N fates for both Paddy and GCRPS.Compared with Paddy,GCRPS reduced N leaching(35.1%–54.9%),ammonia volatilization(0.7%–13.6%),N runoff(71.1%–83.5%),denitrification(3.8%–6.7%),and total N loss(33.8%–56.9%)for all precipitation year types.However,GCRPS reduced crop N uptake and yield during wet years,while increasing crop N uptake and yield during dry and normal years.Fertilizer application reduced the stability and sustainability of rice yield in wet years,but increased the stability and sustainability of rice yield in dry and normal years.In conclusion,GCRPS is more suitable for normal and dry years in the study region,leading to increased rice yield and reduced N loss.
文摘Soil soluble organic matter is an important component in the study of carbon and nitrogen cycling in terrestrial ecosystems. Soil microorganisms, as soil decomposers, participate in soil biogeochemical processes and play an important role in maintaining the balance of soil ecosystems. As a typical subtropical regional unit, Queensland, Australia, is a relatively concentrated distribution area of forests in Australia. It is very sensitive to climate change and plays an important role in Australian climate and even global climate change. Its unique natural environment and ecosystem occupy a special position in the world. However, the knowledge of available carbon and nitrogen pool and microbial activity in forest soil is still very limited. Pinus elliottii, Araucaria cunninghamii and Agathis australis are the three most important forest types in southern Queensland, Australia. In our research, the function and structural diversity of soil microbial communities of these three forest types were studied using biochemical and molecular biological methods, and the effective carbon and nitrogen pools of soil of different forest types and related microbial processes were discussed, which has important theoretical guiding significance for further research on the structure and function of soil ecosystem. The number of PLFAs in the soil of P. elliottii was 45, the number of PLFAs in the soil of Araucaria cunninghamii and Agathis australis was 39 and 35, respectively. The number and content of PLFAs monomer in P. elliottii were higher than those in the other two kinds of forest soil.
基金Supported by 973 Project of National Basic Research Program of China(2006CB403200 )Science and Technology Program of Guizhou Province (S2007-1021,2008-73,TZJF2008-17)National Scientific and Technological Support Project of China(2006BAD03-A0303)~~
文摘[Objective] The research was aimed to study the dynamics of slope runoff and soil erosion in different forest types in karst depression.[Method] Precipitation observation sites at the bottom of karst depression and runoff observation sites in different forest types were established to monitor regularly the main indices changes of runoff and soil erosion at fixed position in 4 years.[Result] The surface runoff of different forest types appeared singer peak from February to November,with lowest valley from June to July.The runoff coefficient appeared double peaks from February to May and from July to September.The changing coefficient of runoff appeared three peaks from March to April,from July to August and from September to November.The silt concentration appeared one peak from March to May and The erosion modulus appeared double peaks from March to May and from June to August.Runoff showed annually reduced trend with the growth of forests and the development of vegetation layer＇s structure.There was a positive correlation between the runoff and its silt concentration in different forest types.Precipitation and evaporation had notable positive correlation with the runoff,and similar correlation but not marked with silt concentration.The fitting analysis results of surface runoff and erosion modulus showed that rocky desertification intensified the unevenness of surface runoff and increased the surface runoff and erosion modulus.The penetrability of surface soil in new planted forest was lower than that in young forest,and that in surface soil of different forest types was higher than in bottom soil.[Conclusion] The research provided theoretical basis for the biological management technologies of water and soil conservation and the control of karst rocky desertification in karst regions.
基金Supported by the Special Fund for Agro-scientific Research in the Public Interest,China(200903024-02)~~
文摘[Objective] Through the investigation of weeds in Coffea arabica orchads in NuJiang River basin, this study aimed to provide scientific guidance for the weed control and improving the ecological and economic benefits of the plantation of Cof- fea arabica. [Method] The types of weeds and the characteristics of weed occur- rence in Coffea arabica orchads in Nujiang River basin were investigated from July to August in 2012. [Result] The results showed that there were 69 types of weeds belonging to 21 families in Coffea arabica orchads. The predominant harmful types were shown as follows： Commelina nudiflora L. ＋ Leptochloa chinensis, Cyperus ro- tundus L. ＋ Bidens pilosa L. ＋ Eleusine indica, Imperata cylindrical ＋ Ageratum conyzoides L. ＋ Eupatorium odoratum L., Ageratum conyzoides L. ＋ Digitaria san- guinalis （L.） Scop. The preponderant weeds consisted mainly of 10 species, namely, Cyperus rotundus L., Commelina nudiflora L., Leptochloa chinensis, Digitaria san- guinalis （L.） Scop, Imperata cylindrical, Bidens pilosa L., Ageratum conyzoides L, E- upatorium odoratum L., Eleusine indica and Chenopodium serotinum L. [Conclusion] The result from this study is of great significance for the plantation of Coffea arabica in Nujiang River basin, as well as the control of weeds.
基金Supported by International Science&Technology Cooperation Program of China(2013DFA61260)Sub-project of National Science and Technology Planning in Rural Areas during the 12th Five-year Plan(2011BAD36B01)~~
文摘In the research, pot experiment and field testing were conducted to study the effect of different crops, soil types, and irrigation modes on biogas slurry diges- tions. The results showed that when silage maize, sweet sorghum and Chinese cabbage were planted in purple soils, the quantities of digested biogas slurry were of 57, 157.5, and 34.5 t/hm2, respectively, while the quantities of digested biogas slurry were 70.5, 157.5 and 40.5 t/hm2 in yellow soils. Besides, the digested biogas slurries reached 36 and 27 t/hm2 as per flood irrigation and sprinkling irrigation when Chinese cabbages were planted in yellow soils. The research indicated crop variety, soil type, and irrigation method all have effects on farmland digestion of biogas slurry.
基金Supported by the Work Project of China Geological Survey(1212010911062)Open Foundation of Karst Dynamics Laboratory(kdl2008-10)+1 种基金Guangxi Zhuang Autonomous Region Innovation Project(0842008)National Natural Science Foundation(40872213)~~
文摘[Objective] The aim was to reveal changes of soil organic matter fraction and their corresponding carbon management indexes as affected by different land use types.[Method]Soil organic carbon,active soil organic carbon and soil carbon management index（CMI）of different land use types in Guilin Maocun karst area were studied.Sampling with field investigation and laboratory testing was carried out.Heavy potassium chromate method was adopted to determine soil organic matter.333 mmol/L KMnO4 oxidation method was used to determine active organic carbon.[Result]With active soil organic matter increasing,the differences of CMI between different land use types were bigger.The CMI value of different land uses was shrubforest paddy fielddry farmland.The statistical analysis showed that labile organic matter was related with major soil properties at a significant level.[Conclusion]Labile organic matter could be used to reveal the influence of different land use types on soil organic matter and carbon management index in karst area.
基金Supported by 973 Project of National Basic Research Program ofChina(2006CB403200)Science and technology program of Guizhou Province(S2007-1021,2008-73,TZJF2008-17)National Scientific and Technological Support Project of China(2006BAD03A0303)~~
文摘[Objective] The aim was to study influences of different land use ways on soil qualities in plateau karst depression.[Method] Different land use types were divided by topographic map of 1∶10 000 scales and soil properties of physics and chemistry were analyzed.[Result] The results showed that the variation trend of soil depth(A+B stratum)was slope plough(include returning farm to forest)land>natural forest land>planted forest land>shrub forest land,and relative indexes changing regularities of soil...
