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Nutrient Losses in Soils on Loess Plateau 被引量:13
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作者 PENGLIN WANGJI-ZENG 《Pedosphere》 SCIE CAS CSCD 1995年第1期83-92,共10页
NutrientLossesinSoilsonLoessPlateanPENGLIN.WANGJI-ZENGandYUCUN-ZUNorthwesternInstituteofSoilandWaterConserua... NutrientLossesinSoilsonLoessPlateanPENGLIN.WANGJI-ZENGandYUCUN-ZUNorthwesternInstituteofSoilandWaterConseruation,AcademiaSini... 展开更多
关键词 黄土高原 土壤养分流失 径流 沉积物 产量 水土流失
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Effects of Accelerated Soil Erosion on Soil Nutrient Loss After Deforestation on the Loess Plateau 被引量:11
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作者 ZHENG Fen-Li 《Pedosphere》 SCIE CAS CSCD 2005年第6期707-715,共9页
Soil erosion and nutrient losses on newly-deforested lands in the Ziwuling Region on the Loess Plateau of China were monitored to quantitatively evaluate the effects of accelerated soil erosion, caused by deforestatio... Soil erosion and nutrient losses on newly-deforested lands in the Ziwuling Region on the Loess Plateau of China were monitored to quantitatively evaluate the effects of accelerated soil erosion, caused by deforestation, on organic matter, nitrogen and phosphorus losses. Eight natural runoff plots were established on the loessial hill slopes representing different erosion patterns of dominant erosion processes including sheet, rill and shallow gully (similar to ephemeral gully). Sediment samples were collected after each erosive rainfall event. Results showed that soil nutrients losses increased with an increase of erosion intensity. Linear relations between the losses of organic matter, total N, NH4-N, and available P and erosion intensity were found. Nutrient content per unit amount of eroded sediment decreased from the sheet to the shallow gully erosion zones, whereas total nutrient loss increased. Compared with topsoil, nutrients in eroded sediment were enriched, especially available P and NH4-N. The intensity of soil nutrient losses was also closely related to soil erosion intensity and pattern with the most severe soil erosion and nutrient loss occurring in the shallow gully channels on loessial hill slopes. These research findings will help to improve the understanding of the relation between accelerated erosion process after deforestation and soil quality degradation and to design better eco-environmental rehabilitation schemes for the Loess Plateau. 展开更多
关键词 黄土高原 土壤侵蚀 水土流失 营养元素
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Nutrient Loss from Various Land-Use Areas in Shixia Small Watershed of Miyun County, Beijing, China 被引量:3
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作者 王晓燕 王晓峰 +2 位作者 王振刚 汪青平 蔡新广 《Chinese Journal Of Geochemistry》 EI CAS 2003年第2期173-178,共6页
In the Shixia small watershed, twenty experimental plots and two monitoring channels, the residential area and livestock areas were used to monitor the flow, runoff and erosion. Nitrogen and phosphorous concentrations... In the Shixia small watershed, twenty experimental plots and two monitoring channels, the residential area and livestock areas were used to monitor the flow, runoff and erosion. Nitrogen and phosphorous concentrations associated with various land uses were analyzed at the same time. The results are presented as follows: (1) TP, TN and COD concentrations of runoff samples in the residential area and livestock areas are nearly 10 times those in other land-use areas. High nutrient loads are associated with village land use, which is due to unsuitable livestock rising. These areas should be treated as the critical areas of non-point source pollution. (2) Different land-use influences intensity the loss of nutrients, especially slope tillings in agricultural land. The amount of nutrient loss from agricultural land per unit is highest, that from forestry is intermediate and that from pastures is lowest. However, in consideration of the variability of land-use areas, agricultural land contributes the greatest to TP and forestry land to TN. (3) The concentrations of TN and TP in sediments from gangues are highest, those in forestry land are intermediate, and those in agricultural land are lowest. Nutrient loss from hilly areas is much greater than from mountainous areas. 展开更多
关键词 土地利用类型 营养损失 北京 农业用地 土壤侵蚀
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Impact of nutrient losses from agricultural lands on nutrient stocks in Dianshan Lake in Shanghai, China 被引量:2
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作者 Shou-bing WANG Xiao-xue MA +2 位作者 Zheng-qiu FAN Wei-qian ZHANG Xiao-yong QIAN 《Water Science and Engineering》 EI CAS CSCD 2014年第4期373-383,共11页
The water quality of Dianshan Lake in Shanghai Municipality, China, is impacted by nutrient losses from agricultural lands around the lake. In this study, nine types of agricultural land use were monitored in 2010 and... The water quality of Dianshan Lake in Shanghai Municipality, China, is impacted by nutrient losses from agricultural lands around the lake. In this study, nine types of agricultural land use were monitored in 2010 and 2011, and a correlation analysis between nutrient losses from agricultural non-point sources(NPS) and nutrient stocks in the lake was conducted over monthly and seasonal time periods. The results indicate that the monthly average concentration of total nitrogen(TN) ranged from 1.41 to 7.34 mg/L in 2010 and from 1.52 to 5.90 mg/L in 2011, while the monthly average concentration of total phosphorous(TP) ranged from 0.11 to 0.26 mg/L in 2010 and from 0.13 to 0.30 mg/L in 2011. The annual loss of TN from agricultural NPS was 195.55 tons in 2010 and 208.40 tons in 2011. The cultivation of water oat made the largest contribution to the loss of TN. The annual loss of TP was 44.58 tons in 2010 and 48.12 tons in 2011, and multi-vegetable cultivation made the largest contribution to the loss of TP. The results of correlation analysis show that the monthly stocks of TN and TP in the lake have a positive correlation with the monthly losses of TN and TP from agricultural NPS. According to the seasonal data, the stocks of TN and TP in the lake both have a much stronger correlation with the losses of TN and TP from agricultural NPS in summer than in other seasons. Agricultural NPS pollution control should be the main focus for the water resource conservation in this area. 展开更多
关键词 营养损失 农田养分 淀山湖 上海市 中国 农业土地利用 面源污染控制 平均浓度
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Soil nutrient loss due to tuber crop harvesting and its environmental impact in the North China Plain 被引量:1
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作者 YU Han-qing LI Yong +3 位作者 ZHOU Na Adrian Chappell LI Xiao-yu Jean Poesen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第7期1612-1624,共13页
Soil loss due to crop harvesting(SLCH) is a soil erosion process that significantly contributes to soil degradation in croplands. However, little is known about soil nutrient losses caused by SLCH and its environmenta... Soil loss due to crop harvesting(SLCH) is a soil erosion process that significantly contributes to soil degradation in croplands. However, little is known about soil nutrient losses caused by SLCH and its environmental impacts. In the North China Plain area, we measured the losses of soil organic carbon(SOC) and nitrogen as well as phosphorus due to SLCH and assessed their relationship with soil particle size composition, agronomic practices and soil moisture content. Our results show that the losses by harvesting potato of SOC, total nitrogen(TN), available nitrogen(AN), available phosphorus(AP) and total phosphorus(TP) were 1.7, 1.8, 1.8, 15.9 and 14.1 times compared by harvesting sweet potato, respectively. The variation of SOC, N and P loss by SLCH are mainly explained by the variation of plant density(PD)(17–50%), net mass of an individual tuber(Mcrop/p)(16–74%), soil clay content(34–70%) and water content(19–46%). Taking into account the current sewage treatment system and the ratio of the nutrients adhering to the tubers during transportation from the field(NTRP/SP), the loss of TN and TP by harvesting of potato and sweet potato in the North China Plain area amounts to 3% N and 20% P loads in the water bodies of this region. The fate of the exported N and P in the sewage treatment system ultimately controls the contribution of N and P to the pollution of lakes and rivers. Our results suggest that a large amount of SLCH-induced soil nutrient export during transportation from the field is a potential pollutant source for agricultural water for vast planting areas of tuber crops in China, and should not be overlooked. 展开更多
关键词 土壤养分流失 作物收获 环境影响 块茎 华北 平原省 污水处理系统 养分损失
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Impact of soil texture and sweetpotato cropping system on soil erosion and nutrient loss in the Three Gorges Reservoir Area of the Changjiang River 被引量:1
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作者 LENG Jin-chuan FU Yu-fan +6 位作者 YANG Chun-xian LIANG Yuan-yuan KONG Ling-ming LUO Yong DUAN Ji-wen LI Bao-chun ZHANG Qi-tang 《Journal of Life Sciences》 2009年第5期30-35,共6页
关键词 土壤质地 土壤侵蚀 种植制度 养分流失 三峡库区 甘薯 长江 有效磷
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Effects of aeolian processes on nutrient loss from surface soils and their significance for sandy desertification in Mu Us Desert, China: a wind tunnel approach 被引量:5
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作者 LANG Lili WANG Xunming +2 位作者 WANG Guangtao HUA Ting WANG Hongtao 《Journal of Arid Land》 SCIE CSCD 2015年第4期421-428,共8页
Mu Us Desert, a region with high aeolian activity, is at extremely high risk of sandy desertification. Using surface soil samples collected from Mu Us Desert of northern China, we evaluated the effects of aeolian proc... Mu Us Desert, a region with high aeolian activity, is at extremely high risk of sandy desertification. Using surface soil samples collected from Mu Us Desert of northern China, we evaluated the effects of aeolian processes on nutrient loss from surface soils by employing wind tunnel experiments. The experiments were conducted using free-stream wind velocities of 14, 16, 18 and 22 m/s. Our results showed that the fine particles(<50 μm in diameter; 12.28% of all transported materials) carrying large nutrient loadings were exported outside the study area by aeolian processes. After the erodible fine particles were transported away from the soil surfaces at low wind velocity(i.e. 14 m/s), the following relatively high wind velocity(i.e. 22 m/s) did not have any significant effect on nutrient export, because the coefficients of variation for soil organic matter, total phosphorus, total nitrogen and available potassium were usually <5%. Our experimental results confirmed that aeolian processes result in a large amount of nutrient export, and consequently increase the risk of sandy desertification in arid and semi-arid ecosystems. 展开更多
关键词 土壤养分流失 毛乌素沙漠 风洞实验 风沙活动 中国北方 沙漠化 表层 半干旱生态系统
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Benefit Assessment of Forest Function in Reducing Soil Erosion and Nutrient Loss in Anji County of Taihu Lake Basin
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作者 Biao ZHANG Jixi GAO +2 位作者 Gaodi XIE Changxin ZOU Bin WANG 《Asian Agricultural Research》 2013年第4期93-96,100,共5页
The non-point source pollution arising from soil erosion is one of the main reasons for the deterioration of the water quality of the Taihu Lake Basin. Forest plays an important role in controlling soil erosion and re... The non-point source pollution arising from soil erosion is one of the main reasons for the deterioration of the water quality of the Taihu Lake Basin. Forest plays an important role in controlling soil erosion and reducing nutrient loss. Based on the survey data on forest resources in Anji County, we estimate the amount of soil erosion and nutrient loss of nitrogen and phosphorus reduced by forest, using soil erosion modulus method and soil nutrient content. In accordance with the degradation coefficient of pollutant and regional compensation standards of environmental resources, we assess the ecological benefits of forest function in reducing nutrient loss of nitrogen and phosphorus in Anji County. The results show that the forest in Anji County can reduce the soil erosion amount at 1.51 million t annually on the average, so as to control the nutrient loss of 1 409 t of total nitrogen and 577 t of total phosphorus in soil, equivalent to annually avoiding the flow of 824 t of total nitrogen and 410 t of total phosphorus into river water; this ecological service function can make forests in Anji County get 92.55 million yuan of ecological compensation funds (about 688 yuan/hm2·a), equivalent to 15 times of the current ecological compensation standard (47 yuan/hm2). The study reveals the importance of forest function in controlling soil erosion and nutrient loss in the upper reaches of Taihu Lake Basin to water environment protection in the basin, conducive to carrying out pollution control and protection work of the water environment in the basin. 展开更多
关键词 FOREST Soil erosion. nutrient control BENEFIT asse
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Assessment of Runoff, Sediment Yields and Nutrient Loss Using the Swat Model in Upper Indus Basin of Pakistan
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作者 Washakh Rana Muhammad Ali Ningsheng Chen +2 位作者 Waque Rana Muhammad Umar Almas Sundas Rahman Mahfuzur 《Journal of Geoscience and Environment Protection》 2020年第9期62-81,共20页
The main objective of this study is to understand the runoff, sediment yield and water quality of the Upper Indus River Basin of Pakistan. To achieve this goal, specific objectives have been met which include, setup o... The main objective of this study is to understand the runoff, sediment yield and water quality of the Upper Indus River Basin of Pakistan. To achieve this goal, specific objectives have been met which include, setup of a hydrological model using Soil and Water Assessment Tool (SWAT) then calibration and validation of the hydrological model using river discharges and in the end investigating the performance of the hydrological model by SWAT. This research will have great impacts on socio-economic conditions of Pakistan because study of upper Indus River basin is imperative to provide data needed for its management, and to warrant that it is sustainable to support the increasing population and conservational flows. A set of programmable mapping components MapWindow Geographic Information System (GIS) was used which is an open source GIS based mapping application. It is SWAT used spatially distributed information on elevation, land use, slope and soil. The program Sequential Uncertainty Fitting ver.2 (SUFI-2) in a combination of uncertainty analysis and calibration of outputs was used in SWAT-CUP. SWAT model used input data, which have climate information to obtain results. The observed climate data of temperature gauges and rain gauge were used as input in the SWAT model;the calibration results for three discharge stations were produced. The initial P-factor value was satisfactory but more iteration to attempt narrow uncertainty band with improving goal function, resulted in small percentage of observed data within uncertainty band. A warm up period of three years (1979-1982) was used for simulation of SWAT model. The model was calibrated for selected three catchments for the period 1982-2000 and validated for period 2001-2010. Results are quite comparable with the observed flows. 展开更多
关键词 Sediment Transport RUNOFF GIS SWAT Model Hydrological Modelling Nu-trient loss
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Water, Energy and Nutrient Losses from Food Wastage of Selected Crops in Three Agro-Climatic Zones in British Columbia, Canada
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作者 Ana Reinesch Lewis Fausak +1 位作者 Anne Joseph Les Lavkulich 《Agricultural Sciences》 CAS 2022年第8期947-972,共26页
Food waste is a growing global concern. Data on the factors and magnitude are largely global estimates, thus local studies aid in providing information on the impacts of food waste. Three important agro-climatic zones... Food waste is a growing global concern. Data on the factors and magnitude are largely global estimates, thus local studies aid in providing information on the impacts of food waste. Three important agro-climatic zones in British Columbia and nine common crops, both annual and perennial, were selected to evaluate the environmental and nutritional implications of local food waste. Using Canadian estimates of total food waste, the constituent water, caloric content, protein, vitamin C, phosphorus and potassium wasted by each crop were estimated. Regionally, the total production and losses were the highest in the Lower Fraser Valley which had high production of potatoes and blueberries, followed by the Okanagan, with grapes and apples, and Vancouver Island, with potatoes. Virtual water was estimated by the BC Agriculture Water Calculator and used to assess the soil and climatic factors impacting the local water demand. Although soil texture seemed to influence water demand, the agro-climatic zone was the main factor controlling the water demand and the corresponding amount of water wasted. Dry agro-climatic zones had annual virtual water up to two times higher for the same crop and soil texture. Lower water demand crops, finer soils and more efficient irrigation systems were more congruent with water stress scenarios. Total losses for each region were based on conservative estimates and would have supplied the caloric energy and protein for over 40,000 adults, and vitamin C for over 300,000 adults for one year. Additionally, the total N, P and K wasted accounted for up to 32, 2 and 13 kg/ha respectively for common fertilizers used in British Columbia. This study confirmed the significance of food waste impacts on local water demand, human nutrition and soil management based on regional data for representative crops. 展开更多
关键词 Food loss Food Waste Crop Water Demand Virtual Water NUTRITION
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The effects of land use on runoff and soil nutrient losses in a gully catchment of the hilly areas:implications for erosion control 被引量:3
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作者 WANG Jun FU Bojie +3 位作者 QIU Yang CHEN Liding CHEN Chen HU Baodong 《Journal of Geographical Sciences》 SCIE CSCD 2005年第4期396-404,共9页
Serious soilerosion is one ofthe majorissues threatening sustainable land use in semiarid areas,especially in the LoessPlateau ofChina.Understanding the effectsofland use on soiland water loss is important for sustain... Serious soilerosion is one ofthe majorissues threatening sustainable land use in semiarid areas,especially in the LoessPlateau ofChina.Understanding the effectsofland use on soiland water loss is important for sustainable land use strategy. Two sub-catchments: catchment A (CA) and catchment B (CB) with distinct land uses were selected to measure soil moisture,runoff and soil nutrientlossin Da Nangou catchmentofthe LoessPlateau ofChina.The effectsofland use patterns on runoffand nutrientlosseswere analyzed based on soilmoisture pattern by kriging and soilnutrients using multiple regression model.The resultsindicated thatthere were significantdifferencesin runoff yield and soil nutrient losses between the two sub-catchments. W ith similar land uses, the CA produced an average sediment yield of 49 kg ha-1 and 22.27 kg ha-1 during two storm events. M eanwhile,there was almostno runoffin the CB with dissimilarland uses during the same events. Bufferzonesshould be established to re-absorb runoffand to trap sedimentsin catchmentwith similar land use structure such as the CA.M oreover,land use managementstrategy aiming to increase the infiltration threshold ofhydrologicalresponse unitscould decrease the frequency ofrunoffoccurrence on aslopeand catchmentscale. 展开更多
关键词 黄土丘陵 小流域 土地利用格局 径流 土壤养分
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Assessment of Economic Loss Caused by Agricultural Non-point Source Nutrient Loss
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作者 FAN Liang-qian CHEN Feng-hui 《Asian Agricultural Research》 2012年第9期67-70,77,共5页
Taking Zhejiang Province as an example, we use the JOHNES export coefficient model to estimate the total nitrogen (TN) and total phosphorus (TP) load of agricultural planting, livestock and poultry breeding and rural ... Taking Zhejiang Province as an example, we use the JOHNES export coefficient model to estimate the total nitrogen (TN) and total phosphorus (TP) load of agricultural planting, livestock and poultry breeding and rural living non-point source in 2009. Based on the protection cost method in environmental economics, we quantitatively assess the economic loss caused by these three types of non-point source nutrient loss. The results show that in TN non-point source load, the load of land for planting accounts for 57.48%, the load of rural living accounts for 30.22%, and the load of livestock and poultry breeding accounts for 12.30%; in TP non-point source load, the load of rural living accounts for 46.18%, the load of livestock and poultry breeding accounts for 29.00%, and the load of land for planting accounts for 24.82%. The economic loss arising from the agricultural non-point source nutrient loss is equivalent to 2.329 424 7 billion yuan per year (the loss from land for planting accounts for 55.46%; the loss from rural living accounts for 31.21%; the loss from livestock and poultry breeding accounts for 13.33%). It indicates that in order to reduce the loss arising from agricultural non-point source nutrient loss, we should pay attention to controlling the land for planting and rural living source. 展开更多
关键词 AGRICULTURAL non-point SOURCE Water ENVIRONMENT EC
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HOTSPOTS OF NUTRIENT LOSSES TO AIR AND WATER:AN INTEGRATED MODELING APPROACH FOR EUROPEAN RIVER BASINS
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作者 Aslihan URAL-JANSSEN Carolien KROEZE +3 位作者 Jan Peter LESSCHEN Erik MEERS Peter J.T.M.VANPUIJENBROEK Maryna STROKAL 《Frontiers of Agricultural Science and Engineering》 CSCD 2023年第4期579-592,共14页
Nutrient pollution of air and water is a persistent problem in Europe.However,the pollution sources are often analyzed separately,preventingthe formulation of integrative solutions.This study aimed to quantify the con... Nutrient pollution of air and water is a persistent problem in Europe.However,the pollution sources are often analyzed separately,preventingthe formulation of integrative solutions.This study aimed to quantify the contribution of agriculture to air,river and coastal water pollution by nutrients.A new MARINA-Nutrients model was developed for Europe to calculate inputs of nitrogen(N)and phosphorus(P)to land and rivers,N emissions to air,and nutrient export to seas by river basins.Under current practice,inputs of N and P to land were 34.4 and 1.8 Tg.yr^(-1),respectively.However,only 12%of N and 3%of P reached the rivers.Agriculture was responsible for 55%of N and sewage for 67%of P in rivers.Reactive N emissions to air from agriculture were calculated at 4.0 Tg.yr^(-1).Almost twofifths of N emissions to air were from animal housing and storage.Nearly a third of the basin area was considered as pollution hotspots and generated over half of N emissions to air and nutrient pollution in rivers.Over 25%of river export of N ended up in the Atlantic Ocean and of P in the Mediterranean Sea.These results could support environmental policies to reduce both air and water pollution simultaneously,and avoid pollution swapping. 展开更多
关键词 agriculture air-water modeling European rivers nutrient pollution sewage systems source attribution
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Hemoglobin loss method calculates blood loss during pancreaticoduodenectomy and predicts bleeding-related risk factors
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作者 Chao Yu Yi-Min Lin Guo-Zhe Xian 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第2期419-428,共10页
BACKGROUND The common clinical method to evaluate blood loss during pancreaticoduoden-ectomy(PD)is visual inspection,but most scholars believe that this method is extremely subjective and inaccurate.Currently,there is... BACKGROUND The common clinical method to evaluate blood loss during pancreaticoduoden-ectomy(PD)is visual inspection,but most scholars believe that this method is extremely subjective and inaccurate.Currently,there is no accurate,objective me-thod to evaluate the amount of blood loss in PD patients.We retrospectively analyzed the clinical data of 341 patients who underwent PD in Shandong Provincial Hospital from March 2017 to February 2019.According to different surgical methods,they were divided into an open PD(OPD)group and a laparoscopic PD(LPD)group.The differences and correlations between the in-traoperative estimation of blood loss(IEBL)obtained by visual inspection and the intraoperative calculation of blood loss(ICBL)obtained using the Hb loss method were analyzed.ICBL,IEBL and perioperative calculation of blood loss(PCBL)were compared between the two groups,and single-factor regression analysis was performed.RESULTS There was no statistically significant difference in the preoperative general patient information between the two groups(P>0.05).PD had an ICBL of 743.2(393.0,1173.1)mL and an IEBL of 100.0(50.0,300.0)mL(P<0.001).There was also a certain correlation between the two(r=0.312,P<0.001).Single-factor analysis of ICBL showed that a history of diabetes[95%confidence interval(CI):53.82-549.62;P=0.017]was an independent risk factor for ICBL.In addition,the single-factor analysis of PCBL showed that body mass index(BMI)(95%CI:0.62-76.75;P=0.046)and preoperative total bilirubin>200μmol/L(95%CI:7.09-644.26;P=0.045)were independent risk factors for PCBL.The ICBLs of the LPD group and OPD group were 767.7(435.4,1249.0)mL and 663.8(347.7,1138.2)mL,respectively(P>0.05).The IEBL of the LPD group 200.0(50.0,200.0)mL was slightly greater than that of the OPD group 100.0(50.0,300.0)mL(P>0.05).PCBL was greater in the LPD group than the OPD group[1061.6(612.3,1632.3)mL vs 806.1(375.9,1347.6)mL](P<0.05).CONCLUSION The ICBL in patients who underwent PD was greater than the IEBL,but there is a certain correlation between the two.The Hb loss method can be used to evaluate intraoperative blood loss.A history of diabetes,preoperative bilirubin>200μmol/L and high BMI increase the patient's risk of bleeding. 展开更多
关键词 PANCREATICODUODENECTOMY Hemoglobin loss Calculated blood loss Estimated blood loss
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Numerical study of alpha particle loss with toroidal field ripple based on CFETR steady-state scenario
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作者 李钮琦 徐颖峰 +1 位作者 钟方川 张德兵 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期503-510,共8页
Effects of plasma equilibrium parameters on the alpha particle loss with the toroidal field ripple based on the CFETR steady-state scenario have been numerically investigated by the orbit-following code GYCAVA. It is ... Effects of plasma equilibrium parameters on the alpha particle loss with the toroidal field ripple based on the CFETR steady-state scenario have been numerically investigated by the orbit-following code GYCAVA. It is found that alpha particle losses decrease and loss regions become narrower with the plasma current increasing or with the magnetic field decreasing. It is because the ripple stochastic transport and the ripple well loss of alpha particle are reduced with the safety factor decreasing. Decrease of the plasma density and temperature can reduce alpha particle losses due to enhancement of the slowing-down effect. The direction of the toroidal magnetic field can significantly affect heat loads induced by lost alpha particle. The vertical asymmetry of heat loads induced by the clockwise and counter-clockwise toroidal magnetic fields are due to the fact that the ripple distribution is asymmetric about the mid-plane, which can be explained by the typical orbits of alpha particle. The maximal heat load of alpha particle for the clockwise toroidal magnetic field is much smaller than that for the counter-clockwise one. 展开更多
关键词 alpha particle loss RIPPLE orbit-following TOKAMAK
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Effect of wall-disruption on nutrient composition and in vitro digestion of camellia and lotus bee pollens
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作者 Yuan Yuan Shun Zhong +3 位作者 Zeyuan Deng Guangyan Li Jinwu Zhang Hongyan Li 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1567-1577,共11页
The nutrient digestion,absorption and biological activity of bee pollen may be limited due to the complex pollen wall.Here,the effect of superfine grinding technology on the release of nutrients from bee pollen were i... The nutrient digestion,absorption and biological activity of bee pollen may be limited due to the complex pollen wall.Here,the effect of superfine grinding technology on the release of nutrients from bee pollen were investigated,and their antioxidant activities and in vitro digestion were explored in this study.Results showed that the content of nutrients in bee pollen increased after wall disruption.Among them,fat content increased by 22.55%-8.31%,protein content increased by 0.54%-4.91%,starch content increased by 36.31%-48.64%,soluble sugar content increased by 20.57%-29.67%,total phenolic acid content increased by 11.73%-86.98%and total flavonoids content increased by 14.29%-24.79%.At the same time,the antioxidant activity increased by 14.84%-46.00%.Furthermore,the active components such as phenolic compounds in the wall-disruption bee pollen were more readily to be released during the in vitro digestion,and easier to be absorbed because of their higher bioaccessibility.Antioxidant activities during in vitro digestion were also improved in walldisruption bee pollen.These findings provide evidence that bee pollen wall disruption was suggested,thus,it is more conducive to exerting the value of bee pollen in functional foods. 展开更多
关键词 Bee pollen nutrientS Wall disruption Phenolic compounds In vitro digestion
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Effect of Saline Water on Soil Acidity, Alkalinity and Nutrients Leaching in Sandy Loamy Soil in Rwamagana Bella Flower Farm, Rwanda
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作者 Abel Mwubahaman Wali Umaru Garba +3 位作者 Hussein Bizimana Jean de Dieu Bazimenyera Eric Derrick Bugenimana Jean Nepomuscene Nsengiyumva 《Agricultural Sciences》 2024年第1期15-35,共21页
The necessity to saline and sodic waters is sometimes used for irrigating agricultural activities under certain circumstances, but it is important to note that the use of these waters comes with specific consideration... The necessity to saline and sodic waters is sometimes used for irrigating agricultural activities under certain circumstances, but it is important to note that the use of these waters comes with specific considerations and limitations. One way to decrease undesirable effects of sodic waters on the physical and chemical properties of soils is to apply organic and chemical amendments within the soil. This study aimed to assess the effectiveness of saline water on soil acidity, alkalinity and nutrients leaching in sandy loamy soil at Bella flower farm, in Rwamagana District, Rwanda. The water used was from the Muhazi Lake which is classified as Class I (Saline water quality). Column leaching experiments using treated soils were then conducted under saturated conditions. The soil under experimental was first analyzed for its textural classification, soil properties and is classified as sandy loamy soil. The t-test was taken at 1%, 5% and 10% levels of statistical significance compared to control soil. The results indicated that the application of saline water to soils caused an increase in some soil nutrients like increase of Phosphorus (P), Potassium (K<sup>+</sup>), Magnesium (Mg2<sup>+</sup>), Sulphur (S), CN ratio and Sodium (Na<sup>+</sup>) and decreased soil texture, physical and chemical properties and remained soil nutrients. Consequently, the intensive addition of saline water leachates to soil in PVC pipes led to decreased of soil EC through leaching and a raiser Soluble Sodium Percentage (SSP). The rate of saline water application affected the increase accumulation of SAR and Na% in the top soil layers. The study indicated that saline water is an inefficient amendment for sandy soil with saline water irrigation. The study recommends further studies with similar topic with saline water irrigation, as it accentuated the alkalinity levels. 展开更多
关键词 nutrientS LEACHING Saline Water Soil Acidity Soil Alkalinity
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Dynamics and genetic regulation of macronutrient concentrations during grain development in maize
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作者 Pengcheng Li Shuangyi Yin +7 位作者 Yunyun Wang Tianze Zhu Xinjie Zhu Minggang Ji Wenye Rui Houmiao Wang Chenwu Xu Zefeng Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期781-794,共14页
Nitrogen(N), phosphorus(P), and potassium(K) are essential macronutrients that are crucial not only for maize growth and development, but also for crop yield and quality. The genetic basis of macronutrient dynamics an... Nitrogen(N), phosphorus(P), and potassium(K) are essential macronutrients that are crucial not only for maize growth and development, but also for crop yield and quality. The genetic basis of macronutrient dynamics and accumulation during grain filling in maize remains largely unknown. In this study, we evaluated grain N, P, and K concentrations in 206 recombinant inbred lines generated from a cross of DH1M and T877 at six time points after pollination. We then calculated conditional phenotypic values at different time intervals to explore the dynamic characteristics of the N, P, and K concentrations. Abundant phenotypic variations were observed in the concentrations and net changes of these nutrients. Unconditional quantitative trait locus(QTL) mapping revealed 41 non-redundant QTLs, including 17, 16, and 14 for the N, P, and K concentrations, respectively. Conditional QTL mapping uncovered 39 non-redundant QTLs related to net changes in the N, P, and K concentrations. By combining QTL, gene expression, co-expression analysis, and comparative genomic data, we identified 44, 36, and 44 candidate genes for the N, P, and K concentrations, respectively, including GRMZM2G371058 encoding a Doftype zinc finger DNA-binding family protein, which was associated with the N concentration, and GRMZM2G113967encoding a CBL-interacting protein kinase, which was related to the K concentration. The results deepen our understanding of the genetic factors controlling N, P, and K accumulation during maize grain development and provide valuable genes for the genetic improvement of nutrient concentrations in maize. 展开更多
关键词 MAIZE nutrient concentration unconditional QTL mapping conditional QTL mapping dynamic trait
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Large-scale interplant exchange of macromolecules between soybean and dodder under nutrient stresses
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作者 Jingxiong Zhang Shalan Li +9 位作者 Wenxing Li Zerui Feng Shuhan Zhang Xijie Zheng Yuxing Xu Guojing Shen Man Zhao Guoyan Cao Xuna Wu Jianqiang Wu 《Plant Diversity》 SCIE CAS CSCD 2024年第1期116-125,共10页
Parasitic plants and their hosts communicate through haustorial connections.Nutrient deficiency is a common stress for plants,yet little is known about whether and how host plants and parasites communicate during adap... Parasitic plants and their hosts communicate through haustorial connections.Nutrient deficiency is a common stress for plants,yet little is known about whether and how host plants and parasites communicate during adaptation to such nutrient stresses.In this study,we used transcriptomics and proteomics to analyze how soybean(Glycine max)and its parasitizing dodder(Cuscuta australis)respond to nitrate and phosphate deficiency(-N and-P).After-N and-P treatment,the soybean and dodder plants exhibited substantial changes of transcriptome and proteome,although soybean plants showed very few transcriptional responses to-P and dodder did not show any transcriptional changes to either-N or-P.Importantly,large-scale interplant transport of mRNAs and proteins was detected.Although the mobile mRNAs only comprised at most 0.2%of the transcriptomes,the foreign mobile proteins could reach 6.8%of the total proteins,suggesting that proteins may be the major forms of interplant communications.Furthermore,the interplant mobility of macromolecules was specifically affected by the nutrient regimes and the transport of these macromolecules was very likely independently regulated.This study provides new insight into the communication between host plants and parasites under stress conditions. 展开更多
关键词 CUSCUTA Mobile molecules nutrient deficiency Host plant-parasitic plant interaction Interplant transport Systemic signaling
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Genetically modified pigs:Emerging animal models for hereditary hearing loss
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作者 Xiao Wang Tian-Xia Liu +7 位作者 Ying Zhang Liang-Wei Xu Shuo-Long Yuan A-Long Cui Wei-Wei Guo Yan-Fang Wang Shi-Ming Yang Jian-Guo Zhao 《Zoological Research》 SCIE CSCD 2024年第2期284-291,共8页
Hereditary hearing loss(HHL),a genetic disorder that impairs auditory function,significantly affects quality of life and incurs substantial economic losses for society.To investigate the underlying causes of HHL and e... Hereditary hearing loss(HHL),a genetic disorder that impairs auditory function,significantly affects quality of life and incurs substantial economic losses for society.To investigate the underlying causes of HHL and evaluate therapeutic outcomes,appropriate animal models are necessary.Pigs have been extensively used as valuable large animal models in biomedical research.In this review,we highlight the advantages of pig models in terms of ear anatomy,inner ear morphology,and electrophysiological characteristics,as well as recent advancements in the development of distinct genetically modified porcine models of hearing loss.Additionally,we discuss the prospects,challenges,and recommendations regarding the use pig models in HHL research.Overall,this review provides insights and perspectives for future studies on HHL using porcine models. 展开更多
关键词 PIGS Animal models Hereditary hearing loss Genetic modification Inner ear
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