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991.
992.
993.
Jamal El Khattabi Barbara Louche Hanan Darwishe Fadi Chaaban Erick Carlier 《Water, air, and soil pollution》2018,229(4):128
In France, the quality of water resources with respect to nitrates deteriorated between the beginning of 1970s and 2000s. A stabilization of the situation and of the improvements has been observed punctually since the 2000s. Despite the application of the Nitrates Directive in France (91/676/CEE), the overall situation remains degraded, with numerous increases in nitrate concentrations in the underground waters. In the North of France, an alluvial groundwater’s nitrate concentration exceeds the drinking water limit fixed at 50 mg/l, in the sectors of Catillon-sur-Sambre and Rejet-de-Beaulieu. In order to quantify and model the impact of agricultural nitrogen on groundwater, an approach based on an integrated model has been established using three specific codes for each lithological horizon: Agriflux (for the root zone), VS2DT (for the unsaturated zone), and ModFlow-MT3D (for the saturated zone). The results illustrate the sensitivity of quality to agricultural crops used. Based on scenarios over 20 years, the predictions show a link between nitrate concentrations in the groundwater and agricultural crops as well as fertilization. Improving quality with a concentration of nitrate less than 50 mg/l requires a reasoned management accompanied by rotations of crops and transformations into grasslands and for sensitive areas the use of the culture producing the least nitrogen flow such as beets. The integrated model constitutes an efficient tool for predicting the evolution of the groundwater quality, especially in sensitive areas like the valleys with a rapid nitrate transfer to the aquifer. The model makes it possible to correctly evaluate the concentrations of nitrates reaching the groundwater with a monitoring of the concentration evolution in each lithological horizon, thus constituting a good tool for the management of agricultural pollution. 相似文献
994.
Tanya Duke-Novakovski Barbara Ambros Cindy Feng Anthony P. Carr 《Veterinary anaesthesia and analgesia》2017,44(3):589-593
Objective
To determine the accuracy of high-definition oscillometry (HDO) for arterial pressure measurement during injectable or inhalation anesthesia in horses.Study design
Prospective, clinical study.Animals
Twenty-four horses anesthetized for procedures requiring lateral recumbency.Methods
Horses were premedicated with xylazine, and anesthesia induced with diazepam–ketamine. Anesthesia was maintained with xylazine–ketamine–guaifenesin combination [TripleDrip (TD; n = 12) or isoflurane (ISO; n = 12)]. HDO was used to obtain systolic (SAP), mean (MAP) and diastolic (DAP) arterial pressures, and heart rate (HR) using an 8-cm-wide cuff around the proximal tail. Invasive blood pressure (IBP), SAP, MAP, DAP and HR were recorded during HDO cycling. Bland–Altman analysis for repeated measures was used to compare HDO and IBP for all measurements. The generalized additive model was used to determine if means in the differences between HDO and IBP were similar between anesthetic protocols for all measurements.Results
There were >110 paired samples for each variable. There was no effect of anesthetic choice on HDO performance, but more variability was present in TD compared with ISO. Skewed data required log-transformation for statistical comparison. Using raw data and standard Bland–Altman analysis, HDO overestimated SAP (TD, 3.8 ± 28.3 mmHg; ISO, 3.5 ± 13.6 mmHg), MAP (TD, 4.0 ± 23.3 mmHg; ISO, 6.3 ± 10.0 mmHg) and DAP (TD, 4.0 ± 21.2 mmHg; ISO, 7.8 ± 13.6 mmHg). In TD, 26–40% HDO measurements were within 10 mmHg of IBP, compared with 60–74% in ISO. Differences between HDO and IBP for all measurements were similar between anesthetic protocols. The numerical difference between IBP and HDO measurements for SAP, MAP and DAP significantly decreased as cuff width:tail girth ratio increased toward 40%.Conclusion and clinical relevance
More variability in HDO occurred during TD. The cuff width:tail girth ratio is important for accuracy of HDO. 相似文献995.
Aline M. Ambrosio Tatiana P.A. Carvalho-Kamakura Keila K. Ida Barbara Varela Felipe S.R.M. Andrade Lara L. Facó Denise T. Fantoni 《Veterinary anaesthesia and analgesia》2017,44(2):254-263
Objective
To examine the intrapulmonary gas distribution of low and high tidal volumes (VT) and to investigate whether this is altered by an alveolar recruitment maneuver (ARM) and 5 cmH2O positive end-expiratory pressure (PEEP) during anesthesia.Study design
Prospective randomized clinical study.Animals
Fourteen client-owned bitches weighing 26 ± 7 kg undergoing elective ovariohysterectomy.Methods
Isoflurane-anesthetized dogs in dorsal recumbency were ventilated with 0 cmH2O PEEP and pressure-controlled ventilation by adjusting the peak inspiratory pressure (PIP) to achieve a low (7 mL kg?1; n = 7) or a high (12 mL kg?1; n = 7) VT. Ninety minutes after induction (T90), an ARM (PIP 20 cmH2O for 10 seconds, twice with a 10 second interval) was performed followed by the application of 5 cmH2O PEEP for 35 minutes (RM35). The vertical (ventral=0%; dorsal=100%) and horizontal (right=0%; left=100%) center of ventilation (CoV), four regions of interest (ROI) (ventral, central-ventral, central-dorsal, dorsal) identified in electrical impedance tomography images, and cardiopulmonary data were analyzed using two-way repeated measures anova.Results
The low VT was centered in more ventral (nondependent) areas compared with high VT at T90 (CoV: 38.8 ± 2.5% versus 44.6 ± 7.2%; p = 0.0325). The ARM and PEEP shifted the CoV towards dorsal (dependent) areas only during high VT (50.5 ± 7.9% versus 41.1 ± 2.8% during low VT, p = 0.0108), which was more distributed to the central-dorsal ROI compared with low VT (p = 0.0046). The horizontal CoV was centrally distributed and cardiovascular variables remained unchanged throughout regardless of the VT, ARM, and PEEP.Conclusions and clinical relevance
Both low and high VT were poorly distributed to dorsal dependent regions, where ventilation was improved following the current ARM and PEEP only during high VT. Studies on the role of high VT on pulmonary complications are required. 相似文献996.
Chutsuda Junsopa Sanun Jogloy Weerasak Saksirirat Patcharin Songsri Thawan Kesmala Barbara B. Shew 《European journal of plant pathology / European Foundation for Plant Pathology》2018,151(1):251-255
Stem rot caused by Sclerotium rolfsii is an important problem for Jerusalem artichoke production. Host plant resistance is the most promising method to control disease. If resistant genotypes can be identified in seedlings and this resistance is closely related to resistance at maturity, the evaluation of disease resistance in adult plants could be curtailed or omitted, increasing the speed and efficiency of screening. The objective of this study was to determine the relationship between resistance to S. rolfsii in Jerusalem artichoke in seedling and in adult stages under field conditions. Field experiments were set up in different soil fertility environments in the rainy season during July to October 2014. In each environment, 10 varieties of Jerusalem artichoke with differences in resistance to S. rolfsii were planted and inoculated either 15 or 45 days after transplanting. Higher disease incidence was observed on adult plant stage, but disease severity was similar for both plant stages. The correlations between seedling and adult responses were positive and significant for disease incidence, area under disease progress curve and severity index. Screening for resistance to S. rolfsii in Jerusalem artichoke can be carried out on seedlings, thus improving the efficiency of selection. 相似文献
997.
Lahoz Ernesto Tarantino Paola Mormile Pasquale Malinconico Mario Immirzi Barbara Cermola Michele Carrieri Raffaele 《植物病害和植物保护杂志》2018,125(3):287-296
Journal of Plant Diseases and Protection - Two field trials in integrated cultivation (2014 and 2016) were carried out with the aim to evaluate the efficacy and the persistence of copper... 相似文献
998.
Development and application of a simple hydrologic model simulation for a Brazilian headwater basin 总被引:1,自引:0,他引:1
Physically based hydrologic models for watersheds are important tools to support water resources management and predict hydrologic impacts produced by land-use change. Grande River Basin is located in southern Minas Gerais State, and the Grande River is the main tributary of Basin which has 2080 km2 draining into the Camargos Hydropower Plant Reservoir (CEMIG — “Minas Gerais State Energy Company”). The objectives of this work were: 1) to create a semi-physically based hydrologic model in semi-distributed to sub-basins approach and based on GIS and Remote Sensing tools and, 2) to simulate the hydrologic responses of the Grande River Basin, thus creating an important tool for management and planning of water resources for region. The hydrologic model is based on the SCS Curve Number (SCS-CN) and MGB/IPH models, and structured into three hydrologic components: estimation of the flow components (quick runoff, hortonian and base flows), propagation into the respective soil reservoirs (surface, sub-surface and shallow saturated zone) and propagation into the channels. Precipitation and discharge data sets were obtained from the Brazilian National Water Agency (ANA). Reference evapotranspiration (ETo) data were obtained from the Brazilian National Meteorological Institute (INMET). In order to estimate actual evapotranspiration, crop coefficient, soil moisture and satellite image interpretation of actual land-use were applied. The long-term hydrologic data series were structured for period between 1990 and 2003. The calibration and validation process was carried out by evaluating the behavior of the Nash–Sutcliffe Coefficient (CNS), obtained from three different combinations of calibration and validation years. This allowed us to evaluate the model performance to simulate years in which El Niño (EN) and La Niña (LN) events were registered (1997–1998 and 1999–2000, respectively). The combinations of calibration and validation years were: the first 7 years to calibrate and remaining 6 years to validate; the first 9 years to calibrate and remaining 4 years to validate; and first 11 years to calibrate and the last 2 years to validate. The statistical precision showed that the model was able to simulate the hydrologic impacts, including years of EN and LN events, with CNS scores greater than 0.70 in both situations. The evaluation of the CNS scores showed small variation in the coefficient as the years of validation decreased. In addition, the model was also able to simulate the hydrologic impacts of land-use change in the Grande River Basin, based on the CNS scores of 0.80 for different combinations of validation periods. The hydrologic impacts in Grande River Basin produced from grassland area converted to eucalyptus under three specific scenarios were evaluated, which predicted annual runoff mean reductions of up to 17.8%, due to an increase in evapotranspiration rate for the eucalyptus plantation. 相似文献
999.
Williams E Stewart-Knox B McConville C Bradbury I Armstrong NC McNulty H 《Public health nutrition》2008,11(2):118-123
OBJECTIVE: To explore the relationship between subjective mood, folate status and homocysteine in healthy individuals. DESIGN: Subjective mood assessments were completed twice daily over the course of one week using the Positive and Negative Affect Scale (PANAS). The PANAS is a validated scale which considers mood state on two distinct continua, one reflecting positive mood and the other negative mood, each requiring response to 10 adjectives on a Likert scale. A blood sample was taken on one occasion at the start of the week during which subjective mood was assessed and analysed for red-blood-cell (RBC) folate, serum folate and plasma homocysteine concentrations. SUBJECTS: Male volunteers aged 19-47 years (n = 58) were recruited from local industries. RESULTS: High concentrations of RBC folate were associated with less variability (lower standard deviation) in negative mood (P = 0.023). Subjective mood, however, was not related to serum folate or homocysteine. CONCLUSIONS: This study appears to be the first to uncover an association between long-term folate status and subjective mood (employing the PANAS) in healthy males. More research is needed to further explore the relationship between nutritional status and mood. 相似文献
1000.
Thaís Chagas Barros Renato de Mello Prado Cassiano Garcia Roque Marcelo Valentin Arf Rafael Gonçalves Vilela 《Journal of plant nutrition》2019,42(5):458-465
Silicon (Si) and salicylic acid (SA) foliar applications can benefit cotton yield especially if there is stress during cultivation. The objective of this study was to evaluate the foliar application of Si and SA on the photosynthetic variables and cotton yield. The experimental design used was randomized complete block, constituted by Si foliar application in potassium and sodium balanced silicate form (0 and 3.6?g L?1 of Si) and SA (0 and 210?mg L?1). The treatments were applied in three leaf sprays during the reproductive stage that coincided with water stress in tillage. Therefore, the Si foliar application associated with SA favors the physiological variables, increasing the photosynthesis, stomatal conductance and water use efficiency reflecting on the increase of cotton yield. 相似文献