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91.
The copepod Tegastes acroporanus is a notorious pest of captive corals in the genus Acropora. In recent years, infestations of T. acroporanus have become widespread among public aquaria and coral propagation facilities and have been largely controlled with the extra-label use of milbemycin oxime formulations (Carl 2008). Many of these drug formulations (which were intended for dogs) have been discontinued by their manufacturers in favor of multidrug products, many of which are unsuitable for corals, forcing experimentation with alternatives. This report provides the first data on populations of T. acroporanus treated with milbemycin oxime and documents the first known use of an otic solution, MilbeMite Otic (Novartis Animal Health U.S., Greensboro, North Carolina), against copepods on live corals. MilbeMite Otic was found to be soluble in seawater and successful at eradicating T. acroporanus in a large exhibit over the course of 6-h waterborne baths (n = 12) at 0.167 µg/L. The resident population of T. acroporanus was also quantified before each treatment to provide the first estimates of coral parasite burden in response to the application of a waterborne chemotherapeutic agent.

Received November 19, 2015; accepted June 7, 2016 Published online October 24, 2016  相似文献   

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Fecal samples were taken at the time of pregnancy examinations and at parturition from two beef herds. They were also taken from sick calves at the onset of disease, and from 25% of the healthy calves at 15 days of age. All fecal samples were examined by electron microscopy for viruses.

Four cows in herd A were detected excreting coronavirus, one at the time of the pregnancy examinations and three at parturition. The first cow was removed from the herd and the others calved at the end of the season. There were no sick calves.

No cows in herd B were detected excreting virus at the time of pregnancy checks, but fourteen coronavirus and two rotavirus carrier cows were found at parturition. All but two calves sampled had large numbers of virus particles in their feces. Clinical illness was associated with dams shedding virus and with nightly low temperatures.

  相似文献   
94.
将部分第二语言习得理论和应用策略汇总,表述语言教育和教学法的系列原则和理论。这些原则和理论解释说明获得第二语言知识能力的惯例和基本规则,探讨学习者个别差异现象重要性,自主学习和指导学习获得第二语言能力的过程以及评估。理解这些理论可以帮助教师制定适当的教学计划,教学策略和合理的教学评估,引导教师和学生遵循低端认知要求,语境嵌入式课程到高端认知要求的连续语言教育和学习发展过程。  相似文献   
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Persistent soil infestations with Phaeolus schweinitzii were successfully established in the forest environment using basidiospores, but there was no evidence that the fungus spread freeely through the soil while existing as a competitive saprophyte. Diseased stumps and roots of Sitka spruce remained a source of sporophore production for more than 17 years, but the principal flush of sporulation occurred within the first 7 years after felling.  相似文献   
97.
The underlying mechanisms governing nonenzymatic pectin and pectate degradation during thermal treatment have not yet been fully elucidated. This study determined the extent of nonenzymatic degradation due to beta-elimination, acid hydrolysis, and demethylation during prolonged heating of citrus pectins and its influence on physicochemical properties. Solutions of citrus pectins, buffered from pH 4.0 to 8.5, were heated at 75, 85, 95, and 110 degrees C for 0-300 min. Evolution of methanol and formation of reducing groups and unsaturated uronides were monitored during heating. Molecular weight and viscosity changes were determined through size exclusion chromatography and capillary viscometry, respectively. Results showed that at pH 4.5, the activation energies of acid hydrolysis, beta-elimination, and demethylation are 95, 136, and 98 kJ/mol, respectively. This means that at this pH, acid hydrolysis occurs more rapidly than beta-elimination. Furthermore, the rate of acid hydrolysis is diminished by higher levels of methyl esterification. Also, citrus pectin (93% esterified) degrades primarily via beta-elimination even under acidic conditions. Acid hydrolysis and beta-elimination caused significant reduction in relative viscosity and molecular weight.  相似文献   
98.
This article offers some tips on working with statistics and develops four relatively simple procedures to deal with most kinds of data with which veterinarians work. The criterion for a procedure to be a "Hood of the Truck Statistics" (HOT Stats) technique is that it must be simple enough to be done with pencil, paper, and a calculator. The goal of HOT Stats is to have the tools available to run quick analyses in only a few minutes so that decisions can be made in a timely fashion. The discipline allows us to move away from the all-too-common guess work about effects and differences we perceive following a change in treatment or management. The techniques allow us to move toward making more defensible, credible, and more quantifiably "risk-aware" real-time recommendations to our clients.  相似文献   
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C99 is the transmembrane carboxyl-terminal domain of the amyloid precursor protein that is cleaved by γ-secretase to release the amyloid-β polypeptides, which are associated with Alzheimer's disease. Nuclear magnetic resonance and electron paramagnetic resonance spectroscopy show that the extracellular amino terminus of C99 includes a surface-embedded "N-helix" followed by a short "N-loop" connecting to the transmembrane domain (TMD). The TMD is a flexibly curved α helix, making it well suited for processive cleavage by γ-secretase. Titration of C99 reveals a binding site for cholesterol, providing mechanistic insight into how cholesterol promotes amyloidogenesis. Membrane-buried GXXXG motifs (G, Gly; X, any amino acid), which have an established role in oligomerization, were also shown to play a key role in cholesterol binding. The structure and cholesterol binding properties of C99 may aid in the design of Alzheimer's therapeutics.  相似文献   
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