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141.
Andrea Cote Ryan M. Wallace David A. Jackson Maria A. Said Karl Musgrave Cuc H. Tran Clayton Van Houten Alexia Harrist Danielle Buttke Ashley Busacker Veronica Pickens Sarah Anne J. Guagliardo 《Zoonoses and public health》2019,66(5):504-511
Mass bat exposures (MBEs) occur when multiple people are exposed to a bat or a bat colony, often over an extended period. In August 2017, a public health investigation was started in response to an MBE that occurred during May–August 2017 at a national park research station in Wyoming. We identified 176 people who had slept primarily in two lodges (Lodges A and B) at the research station, and successfully contacted 165 (93.8%) of these individuals. Risk assessments (RAs) were administered to all 165 individuals to determine degree and type of exposures to bats (e.g., biting or scratching). Exposure status for research station guests was classified as “non‐exposed,” “low risk” or “high risk,” and counselling was provided to guide post‐exposure prophylaxis (PEP) recommendations. Prior to public health notification and intervention, 19 persons made the decision to pursue PEP. The healthcare‐seeking behaviours of this group were taken to represent outcomes in the absence of public health intervention. (These persons received a RA, and their risk classification was retrospectively assigned.) Approximately 1–2 weeks after conducting the RAs, we conducted a follow‐up survey to determine whether recommendations regarding PEP were ultimately followed. The proportion of individuals that unnecessarily pursued PEP was higher among the 19 individuals that sought health care prior to receiving the RA (p < 0.00001). Among those receiving the RA first, all persons classified as high risk followed public health guidance to seek PEP treatment. Despite this, upon re‐interview, only 21/79 (26.6%) of guests could accurately recall their risk classification, with most people (55.7%) overestimating their risk. Study findings demonstrate that early public health interventions such as RAs can reduce unnecessary use of PEP and that messaging used during rabies counselling should be clear. 相似文献
142.
David Süss Michael Iwersen Vanessa Schweinzer Erika Gusterer Peter Kanz Stefanie Krieger Harald Pothmann Karen Wagener Michael Hoelker Dawit Tesfaye Karl Schellander Ariane Helmbrecht Claudia Parys Marc Drillich 《Reproduction in domestic animals》2019,54(9):1265-1273
There is evidence that supplementing methionine has positive effects on uterine environment, oocyte quality and embryo development in cattle. Thus, the objective of this study was to evaluate reproductive traits of cows supplemented with rumen‐protected methionine (RPM) during early to mid‐lactation in comparison with an untreated control group (CON). An additional focus was on the effect of puerperal diseases on reproductive performance parameters in RPM‐supplemented group MET and in CON. A total of 1,709 multiparous Holstein‐Friesian cows were enrolled in this field trial conducted on a commercial dairy farm in Slovakia. Cows were allocated at approximately 12 days post‐partum (dpp) to either CON or MET, the latter supplemented with 25.0 g–27.2 g RPM per cow per day incorporated into the total mixed ration (TMR) until leaving the study pen at approximately 140 dpp. The amount of RPM was calculated based on individual feed ingredients analysis and adjusted during the study period when TMR changed. Cows were monitored during the post‐partum period by vaginal examination (day 5 pp), measuring of beta‐hydroxybutyrate in blood (3, 5, and 8 dpp) and by vaginal examination, uterine cytology and measuring of back fat thickness by ultrasound (all at 31 ± 3 dpp). Compared with CON, cows supplemented with RPM did not show better reproduction performance parameters (first service submission rate, days to first service, conception risk, days open 140). Results from binary logistic regression model for the risk of conception showed that metritis had a significant effect, but the supplementation of methionine had not. Results of Cox regression analysis for the odds of conception within 140 dpp revealed only metritis and clinical endometritis as significant factors. In conclusion, supplementation of RPM had no beneficial effect on reproductive performance in this study farm compared with an untreated control group. 相似文献
143.
Liza Wittenberg-Voges Sabine BR. Kästner Marja Raekallio Outi M. Vainio Karl Rohn Klaus Hopster 《Veterinary anaesthesia and analgesia》2018,45(2):165-174
Objective
To compare the effects of MK-467 during isoflurane anaesthesia combined with xylazine or dexmedetomidine on global and gastrointestinal perfusion parameters.Study design
Prospective, randomized experimental trial.Animals
A total of 15 warmblood horses.Methods
Horses were divided into two groups for administration of either dexmedetomidine (D) or xylazine (X) for premedication (D: 3.5 μg kg?1; X: 0.5 mg kg?1) and as constant rate infusion during isoflurane anaesthesia (D: 7 μg kg?1 hour?1; X: 1 mg kg?1 hour?1). During anaesthesia, heart rate, mean arterial blood pressure (MAP), systemic vascular resistance index (SVRI) and cardiac index (CI) were measured. Microperfusion of the colon, jejunum and stomach was measured using laser Doppler flowmetry. After 2 hours of stabilization, MK-467 (250 μg kg?1) was administered, and measurements were continued for another 90 minutes. For statistical analysis, the permutation test and Wilcoxon rank-sum test were used (p < 0.05).Results
There were no differences in baseline measurements between groups. The MK-467 bolus resulted in a significant decrease in MAP (D: –58%; X: –48%) and SVRI (D: –68%; X: –65%) lasting longer in group D (90 minutes) compared to group X (60 minutes). While CI increased (D: +31%; X: +35%), microperfusion was reduced in the colon (D: –44%; X: –34%), jejunum (D: –26%; X: –33%) and stomach (D: –37%; X: –35%).Conclusions and clinical relevance
Alpha-2-agonist induced vasoconstriction was reversed by the MK-467 dose used, resulting in hypotension and rise in CI. Gastrointestinal microperfusion decreased, probably as a result of insufficient perfusion pressure. An infusion rate for MK-467 as well as an ideal agonist/antagonist ratio should be determined. 相似文献144.
Karl Heinrich Hartge 《植物养料与土壤学杂志》2001,164(3):247-252
Soil as a volume — means to record its changes on profile basis Compaction and loosening of soils always means change of its total volume. Since such changes cannot occur downward, or sideways beyond the effect of closing cracks after previous shrinkage, the total effect is a change in the level of the soil surface. Such changes can be assessed by aid of the void ratio‐depth relation. This function is treated as an analogy to the compression curve of classical soil mechanics as obtained by 1‐dimensional confined oedometer measurement. It was termed as packing characteristic in earlier papers. Starting at this curve the solid volume for a freely chosen depth/vertical stress level in the soil column is calculated to be used as reference level. To this column the related height of pores is added which is calculated from the void‐ratio/vertical stress diagram. By this method the upper end of this calculation has to be chosen to be e.g. ca. 0.4 cm below proper surface. Using this procedure volume i.e. height changes can be compared for deliberately chosen soil profiles, fresh sediments, and artificial land fills. An important item for the precision of the result is the correctness of the assumption for linearity of the packing characteristic. This assumption was tested using sets of values from 63 soils. The observed deviations are interpreted in terms of mechanisms that may cause them. 相似文献
145.
The following parameters were measured on seven field plots at 3 sites which had been under organic farming for different periods of time: mineral nitrogen (N min) contents, in situ net nitrogen mineralization (N net), soil microbial biomass carbon (C mic), and nitrogen (N mic) contents, and extractable organic N contents. The measurements were conducted every three weeks from spring 1995/1996 to autumn 1997. The objective was to test whether, under organic farming: 1) temporal fluctuations of Nmic contents over the course of the year are indicative for a source‐and‐sink function for plant‐available N of the soil microbial biomass, and 2) temporal variations in Nmic content can be related with in situ Nnet or plant N uptake. Nmin contents gradually increased after ploughing in autumn until late winter. During intensive plant growth in spring, values rapidly declined. In situ Nnet fluctuated only moderately and reached high values during intensive plant growth (May—July) as well as after soil cultivation in autumn. The Cmic and Nmic contents generally were low in winter, increased in spring and reached maxima in late spring or summer. In spring, the increase in Cmic contents preceded the increase in Nmic contents, resulting in elevated Cmic:Nmic ratios until shooting of winter wheat. This corresponds to an uptake of available soil nitrogen by the plants at the expense of soil micro‐organisms. The subsequent increase in Nmic contents, coinciding with high plant N uptake rates, indicates an enhanced, plant‐induced N mobilization at that time. Possible mobilization mechanisms are discussed. Soil microbial biomass exerted a source‐and‐sink function for extractable organic N on some of the field plots. Estimates of in situ Nnet measurements were neither correlated significantly with soil microbial biomass N, Nmic flux, Nmic turnover, nor with plant N uptake. Lower Nmic turnover rates on 41 years versus 3 years organically managed fields indicate a stabilizing effect of organic farming on soil microflora. 相似文献
146.
Complete removal of roots from soil samples is a prerequisite for most of the chemical and biological analyses. A simple electrostatic method of separating roots from sieved, largely mineral soil substrates was optimized and examined by the addition of 14C labeled fine roots to sandy, silt loamy and clay loamy samples. Depending on soil texture, between 40% and 50% of fine roots can be removed from 100 g of sieved soil in less than 10 minutes. The root‐free soil substrate and the extracted roots can be used for analyzes or experiments immediately after the separation. The proportion of the mineral particles remaining in the root fraction depends on duration of separation, distance between the charged plate and the sample, and soil texture. The proportion of separated mineral particles is about 90%—95% (w/w) in sandy and 70%—85% in silt loamy and clay loamy substrates. The electrostatic method of root separation may take place before the analysis of Ct and Nt contents, and is suitable for soil samples preparation for incubation experiments. 相似文献
147.
Dispersion and migration of fine particles in two palygorskite‐containing soils of the Jordan Valley
Migration of different mineral particles within columns of soil‐sand mixtures containing 10 or 20 mass % of soil was investigated by establishing differences in the mineral suite between the ”︁bulk clay” and the ”︁mobile fine material” fractions. The ”︁bulk clay” fractions of all soils contained smectite, palygorskite, kaolinite, quartz, feldspar, and calcite. The soils were saturated with sodium by leaching with NaCl solution, and then leached with distilled water. Clay dispersion and particle migration occurred in the columns. Values of SAR (sodium adsorption ratio) of the effluent decreased with time due to carbonate dissolution. At a certain SAR value, the clays apparently formed aggregates, and as a consequence particle migration stopped in the column. In addition to clay‐sized particles (< 2 μm), very‐fine‐silt‐sized particles (2— 5 μm) were able to migrate in the soil‐sand mixtures, too, and to some extent fine‐silt‐sized particles (5—10 μm) as well. Average size of mobile particles decreases with increase of soil content in the soil‐sand mixtures. The mineralogical composition of the ”︁mobile fine material” changed during the experiment. At the beginning of the experiment, the ”︁mobile fine material” was enriched in the non‐phyllosilicates (especially in calcite, and in some cases in quartz, feldspar and dolomite) and contained low concentrations of phyllosilicates (smectite, palygorskite and kaolinite). At the end of the experiment, the proportion of non‐phyllosilicates decreased, and as a consequence, the proportion of phyllosilicates increased. Among the non‐phyllosilicates, calcite was the most mobile mineral. Among the phyllosilicates, palygorskite was preferentially mobilized in topsoil horizons. In subsoil horizons, on the other hand, kaolinite was preferentially mobilized. This difference was explained by the different nature of carbonates in the topsoil and subsoil horizons. Palygorskite is preferentially occluded within the soil carbonates of lacustrine origin over smectite and kaolinite. These carbonates are present mainly in the subsoil horizons. As a consequence, the presence of these carbonates in the subsoil horizons decreases the migration of mainly palygorskite. 相似文献
148.
Joaquín Soler Catherine Boisneau Philippe Jug Nina Richard Yann Guerez Laure Morisseau Karl Matthias Wantzen Rafael Araujo 《水产资源保护:海洋与淡水生态系统》2019,29(10):1758-1770
- 相似文献
149.
Correlating phosphorus extracted by simple soil extraction methods with foliar phosphorus concentrations of Picea abies (L.) H. Karst. and Fagus sylvatica (L.)
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Phosphorus (P) concentrations in needles and leaves of forest trees are declining in the last years in Europe. For a sustainable forest management the knowledge of site specific P nutrition/availability in forest soils is vital, but we are lacking verified simple methods for the estimation of plant available P. Within this study, four soil P extraction methods [water ( ), double‐lactate (Plac), citric acid (Pcit), and sodium bicarbonate ( )], as well as total P content of the soil (Ptot) were tested to investigate which method is best correlated with foliar P concentrations of spruce [Picea abies (L.) H. Karst.] and beech [Fagus sylvatica (L.)]. Mineral soil samples from 5 depth levels of 48 forest sites of the Bavarian sample set of the second National Forest Soil Inventory (BZE II) were stratified according to tree species (spruce and beech) and soil pH (pH < 6.2 and > 6.2), covering the whole range of P nutrition. The extractable amount of P per mass unit of soil increased in the order << Plac < < Pcit, decreased with soil depth, and was higher in soils with pH < 6.2. Citric acid extracted up to 10% of Ptot in acidic soils. Whereas Pcit delivers adequate regression models for P nutrition in the case of spruce (R2 up to 0.53) and beech (R2 up to 0.58) for acidic soils, shows good results for spruce growing on acidic soils (R2 up to 0.66) and for beech on soils with pH > 6.2 (R2 up to 0.57). Plac produces adequate models only for beech on high pH soils (R2 up to 0.64), while did not produce acceptable regression models. Ptot seems suitable to explain the P nutrition status of beech on acidic (R2 up to 0.62) and alkaline soils (R2 up to 0.61). Highest R2s are obtained mostly in soil depths down to 40 cm. As and Pcit showed good results for both investigated tree species, they should be considered preferentially in future studies. 相似文献
150.