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411.
The juçara fruits (Euterpe edulis Martius), native to the Atlantic Forest, are rich in anthocyanins. To preserve the anthocyanins in juçara fruit pulp, this study aimed to evaluate the effectiveness of microencapsulation by spray drying and freeze drying with maltodextrin (dextrose equivalent 16.5 to 19.5) and gum arabic in different proportions. The obtained microparticles were characterized by quantifying the total polyphenol and anthocyanin contents, by performing differential scanning calorimetry, thermogravimetry, and infrared spectroscopy and by using scanning electron microscopy to analyze the morphology of the particles. The total amount of polyphenols in the fruit pulp was 750?±?16.7 mg GAE/100 g of the freeze-dried sample. The total anthocyanins in the fruit pulp was 181.25?±?5.36 (mg/100 g). The microparticles were formed by employing maltodextrin and gum arabic in a 1:1 proportion as the polymeric matrix; the mixtures of pulp and polymeric matrix were prepared in proportions of 2:3 and 2:1, preserving up to 83.69% of the anthocyanin content. Lyophilization of the 2:1 mixture resulted in an anthocyanin content of 116.89?±?4.43 (mg/100 g), whereas lyophilization of the 2:3 mixture resulted in 151.68?±?1.39 (mg/100 g) anthocyanin content, which did not differ from the value obtained by spray drying the 2:3 mixture (150.76?±?5.79 (mg/100 g)). Thermal analyses showed that the microparticles obtained by freeze drying at a ratio of 2:3 presented greater resistance to degradation with increasing temperature. The incorporation of the pulp in the polymeric matrix was demonstrated by IR analyses. Microparticles obtained by freeze drying showed the formation of various-sized flakes, whereas those obtained by spray drying were spherical in shape. Microencapsulation is a possible alternative for improving the stability of the anthocyanins in this fruit.  相似文献   
412.
The two storms Vivian (1990) and Lothar (1999) left an area of roughly 9000 ha of fully damaged protection forests in Swiss mountain regions. Given this huge dimension, questions arose on how to manage these areas to keep the protection gap, i.e. the time period with reduced overall protection against natural hazards, short. Quantifications are presented for the stability of lying logs left in place, the frequency of post-disturbance mass movements, and the tree regeneration in windthrow areas. The average height above ground of unsalvaged lying logs decreased from 2.1 m shortly after disturbance to 0.8 m 20 years later. In the period 1990–2014, the number of avalanches in windthrow areas was markedly small, and annual rates of shallow landslides and debris flows in windthrow areas did not differ from rates in comparable undamaged forested areas. Regeneration density rarely exceeded 4000 stems ha?1 20 years post-windthrow at elevations above 1200–1500 m a.s.l. Mean height of tallest trees reached 5.6 m in areas that were cleared and 6.5 m in those left unsalvaged. Trees planted post-windthrow were 1.0–2.4 m taller than naturally regenerated ones. Practitioners rated the protective effect to be acceptable 24 years post-disturbance in only 5 out from 16 observed windthrow areas (31%), with planting trees as the main cause of success. We conclude that in protection forests the regeneration speed after disturbance rarely meets practitioner’s expectations in terms of both stem density and stand structure. However, leaving woody debris from wind disturbance in place proved to replace protective effects for an astonishingly long time. An intensive management with salvage logging, planting and even technical constructions seems therefore only inevitable on windthrown areas where risks seem too high based on hazard, damage potential and possible spread of bark beetles to nearby protection forests. A management alternative applicable to many other cases of windthrown protection forests is to plant trees between lying stems.  相似文献   
413.

Objectives

Neostigmine is routinely used to reverse non-depolarizing neuromuscular block. Given its indirect mechanism, a plateau may exist whereby increasing doses of neostigmine do not result in clinical benefit. This study was designed to measure the speed of reversal of vecuronium-induced neuromuscular block in isoflurane-anesthetized dogs after the administration of three doses of neostigmine as used in clinical practice.

Study design

Prospective, crossover, randomized study.

Animals

Seven adult, mixed-breed dogs with a mean ± standard deviation (SD) age of 2.0 ± 0.8 years and weight of 19.1 ± 9.1 kg.

Methods

Dogs were anesthetized on three occasions with isoflurane and administered vecuronium (0.1 mg kg–1) intravenously (IV). The train-of-four (TOF) ratio was measured on the pelvic limb with acceleromyography. When the second twitch of the TOF had returned spontaneously, atropine (0.03 mg kg–1) and neostigmine (0.02, 0.04 or 0.07 mg kg–1) were administered IV. Time to reach a TOF ratio of ≥0.9 after neostigmine administration was recorded.

Results

Increasing the dose of neostigmine from 0.02 mg kg–1 to 0.04 mg kg–1 and 0.07 mg kg–1 resulted in significant reductions in mean ± SD reversal times (10.5 ± 2.3, 7.4 ± 1.1 and 5.4 ± 0.5 minutes, respectively) (p < 0.0001) and smaller coefficients of variation (22%, 15% and 10%, respectively).

Conclusions and clinical relevance

Increasing the dose of neostigmine from 0.02 mg kg–1 to 0.04 mg kg–1 and 0.07 mg kg–1 produced faster and less variable reversal of vecuronium-induced neuromuscular block in isoflurane-anesthetized dogs. No ceiling effect was observed at this dose range.  相似文献   
414.

An investigation was made into the feeding behavior of goats to evaluate the effects of a detoxified castor bean meal in the diet of goats. Thirty-six ½ crossbred Boer goats were used, with an average weight of 20?±?3.2 kg. A completely randomized design was used with four treatments (diets with of 0, 100, 200, and 300 g detoxified castor bean meals/kg dry matter) and nine replicates. Castor bean meal was detoxified using calcium oxide. Diets were formulated to be isonitrogenous, and the forage:concentrate ratio was 50:50. The feeding behavior was observed on the 17th, 45th, and 70th days of the experiment. For the evaluation of feeding behavior (feeding, idle, and rumination times), the animals were observed in 5-min intervals for 24 h. The addition of detoxified castor bean meal did not change (P?>?0.05) the evaluated behavioral variables. Linear reduction was observed (P?<?0.05) in the efficiencies of feeding and rumination, expressed in g dry matter/h. The variables related to the time series discretization of the feeding behavior of goats did not change (P?>?0.05) with the inclusion of detoxified castor bean meal. The inclusion of detoxified castor bean meal in growing goats’ diets does not change the feeding, rumination, and idle times, however, decreases intake, feeding, and rumination efficiencies of dry matter.

  相似文献   
415.
Hematophagous gastrointestinal parasites cause significant economic losses in small ruminant grazing systems. The growing reports of multi-drug resistant parasites call for intensive research on alternative treatments for anthelmintics to help small ruminants cope with these parasites. Two-month-old lambs with mean body weight (BW) of 22.5 kg were experimentally infected with a multidrug-resistant Haemonchus contortus strain. Infected animals were dosed orally with Cymbopogon schoenanthus essential oil to evaluate its anthelmintic potential. Eighteen animals were allocated into three groups of six animals, and each received one of the following treatments: Group 1 - control (10 mL of water), Group 2 - C. schoenanthus essential oil (180 mg/kg BW); and Group 3 - C. schoenanthus essential oil (360 mg/kg BW). Animals received the oil once a day for 3 consecutive days. Lambs were evaluated clinically for blood biochemistry before, at 1, 5, 10, 15 and 20 days after treatment, and then were euthanized to assess the total worm burden. No statistically significant reduction in fecal egg count, packed cell volume or total worm count was observed after treatments. Also, no statistical difference among group means for blood levels of urea, creatinine, albumin, alkaline phosphatase, aspartate aminotransferase and gamma glutamyl transferase was found. Larval development assay (LDA) and egg hatch assay (EHA) were performed from feces of treated animals at 1, 5, 10 and 15 days after essential oil administration. An inhibition in LDA was observed 1 day after the 3-day treatment in larvae from feces of animals treated with 360 mg/kg essential oil. In conclusion, the essential oil at the doses of 180 mg/kg and 360 mg/kg was safe to sheep, but failed as an anthelmintic treatment when applied to young sheep artificially infected with a multidrug-resistant H. contortus strain.  相似文献   
416.
This trial was conducted to assess the efficacy of a?ai seeds in the diet of sheep, specifically, to evaluate the intake, digestibility, and weight gain in sheep that are fed with diets containing four different mixtures of a?ai seeds and coastcross hay. Sixteen noncastrated male sheep with an average initial body weight of 22?kg were randomly assigned to one of four diet treatments using initial body weight as a covariate. The diets used coastcross hay as the basal roughage in a 60:40 roughage/concentrate ratio. The concentrate was the same in all the treatments. The a?ai seed was added to the diet as a partial substitute for the coastcross hay to make up four diet treatments: 0 (control), 5, 10, and 15?% a?aí added to the diet on a dry matter basis. The daily weight gain, final body weight, and feed intake were found to linearly increase with the increase in added dietary a?ai seed meal (P?相似文献   
417.
Wearable sensors have been explored as an alternative for real-time monitoring of cattle feeding behavior in grazing systems. To evaluate the performance of predictive models such as machine learning (ML) techniques, data cross-validation (CV) approaches are often employed. However, due to data dependencies and confounding effects, poorly performed validation strategies may significantly inflate the prediction quality. In this context, our objective was to evaluate the effect of different CV strategies on the prediction of grazing activities in cattle using wearable sensor (accelerometer) data and ML algorithms. Six Nellore bulls (average live weight of 345 ± 21 kg) had their behavior visually classified as grazing or not-grazing for a period of 15 d. Elastic Net Generalized Linear Model (GLM), Random Forest (RF), and Artificial Neural Network (ANN) were employed to predict grazing activity (grazing or not-grazing) using 3-axis accelerometer data. For each analytical method, three CV strategies were evaluated: holdout, leave-one-animal-out (LOAO), and leave-one-day-out (LODO). Algorithms were trained using similar dataset sizes (holdout: n = 57,862; LOAO: n = 56,786; LODO: n = 56,672). Overall, GLM delivered the worst prediction accuracy (53%) compared with the ML techniques (65% for both RF and ANN), and ANN performed slightly better than RF for LOAO (73%) and LODO (64%) across CV strategies. The holdout yielded the highest nominal accuracy values for all three ML approaches (GLM: 59%, RF: 76%, and ANN: 74%), followed by LODO (GLM: 49%, RF: 61%, and ANN: 63%) and LOAO (GLM: 52%, RF: 57%, and ANN: 57%). With a larger dataset (i.e., more animals and grazing management scenarios), it is expected that accuracy could be increased. Most importantly, the greater prediction accuracy observed for holdout CV may simply indicate a lack of data independence and the presence of carry-over effects from animals and grazing management. Our results suggest that generalizing predictive models to unknown (not used for training) animals or grazing management may incur poor prediction quality. The results highlight the need for using management knowledge to define the validation strategy that is closer to the real-life situation, i.e., the intended application of the predictive model.  相似文献   
418.
419.
In situ and in vitro techniques were employed to investigate the metabolic changes caused by Tomato spotted wilt virus in hypersensitive and susceptible hosts; Petunia hybrida and Nicotiana tabacum, respectively. In petunia, H2O2 accumulation preceded increased peroxidase and shikimate dehydrogenase activity at local lesion sites. In systemic tobacco plants, peroxidase activity was induced prior to symptom onset and the activity of shikimate dehydrogenase was disrupted upon viral infection. Taken together, our data suggest that reactive oxygen species-based mechanisms of defense are shared by hypersensitive and susceptible hosts, although downstream components and regulatory mechanisms are distinct.  相似文献   
420.
Published serum cholesterol values in captive western lowland gorillas (Gorilla gorilla gorilla) are much higher than human ranges, with a national mean of 7.36 mmol/L (284 mg/dl, n = 863). Complete blood lipid profiles were examined in 15 captive gorillas. High-density lipoprotein (HDL) was found to decrease more rapidly with age than total cholesterol, resulting in an increasing ratio of cholesterol HDL with age. The ratio of apolipoprotein B to apolipoprotein Al also increased with age. Establishment of a database of blood lipid values for captive gorillas with correlative analysis of animals with known atherosclerosis status may help to identify sensitive predictors of coronary heart disease risk.  相似文献   
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