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1.
Sulfluramid is an expensive active principle of insecticidal baits that is lost by volatilization during the pelletization of baits. To increase the thermal stability of sulfluramid, we tested its molecular encapsulation in beta-cyclodextrin (beta-CD), using molar ratios of 1:1 and 1:2 (sulfluramid:beta-CD), using the complex preparation techniques of coprecipitation and kneading. The physical mixture of sulfluramid and beta-CD was also tested for comparison. The products of complexation were characterized by differential scanning calorimetry, thermogravimetry, and derivative thermogravimetry, indicating the formation of a sulfluramid/beta-CD complex and showing that the release of the complexed sulfluramid occurs in the range of 270-300 degrees C, a temperature range that is well above the temperature at which sulfluramid sublimates (40 degrees C). This result warrants a reduced sulfluramid loss in the preparation of insecticidal baits. The preparation of the complex by kneading with molar ratio of 1:2 gave the highest yield of complex, about 64%, in relation to the theoretical maximum.  相似文献   
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INDEPTH seismic reflection profiling shows that the decollement beneath which Indian lithosphere underthrusts the Himalaya extends at least 225 kilometers north of the Himalayan deformation front to a depth of approximately 50 kilometers. Prominent reflections appear at depths of 15 to 18 kilometers near where the decollement reflector apparently terminates. These reflections extend north of the Zangbo suture to the Damxung graben of the Tibet Plateau. Some of these reflections have locally anomalous amplitudes (bright spots) and coincident negative polarities implying that they are produced by fluids in the crust. The presence of geothermal activity and high heat flow in the regions of these reflections and the tectonic setting suggest that the bright spots mark granitic magmas derived by partial melting of the tectonically thickened crust.  相似文献   
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Myophosphorylase deficiency (glycogen storage disease Type V) has been diagnosed in Charolais calves in New Zealand. It is manifested as exercise intolerance and recumbency, usually at several weeks of age, due to an inability to mobilise glucose, as glucose phosphate, from glycogen. Affected calves may rise and walk after a rest to again become affected on further exercise. There is rhabdomyolysis and after repeated or severe attacks the calf may remain recumbent and need to be euthanised. The mutant phosphorylase gene has been described. We have established a PCR-RFLP test based on a published method, and have confirmed the diagnosis in affected calves and heterozygous status of sires, dams and other related individuals belonging to an extended family. In addition, several other non-related heterozygotes have been identified in that and another herd. There appears to have been importations of the gene from both England and America.  相似文献   
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AIM: To describe a disease of muscle in Charolais calves and confirm the putative diagnosis of inherited myophosphorylase deficiency.

METHODS: Variously stained paraffin sections of muscle prepared from affected calves were used to describe the lesions. A polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) test was developed and applied to affected calves, their sires, dams and other individuals.

RESULTS: The lesions were those of rhabdomyolysis of skeletal muscles and sub-sarcolemmal spaces in normal fibres. The PCR-RFLP test confirmed the expected mutation for phosphorylase deficiency of Charolais cattle in two affected calves. In addition, sires, dams and other closely-related individuals of four affected calves tested as heterozygous for the mutation. Other apparently unrelated animals also tested as heterozygous.

CONCLUSIONS: The diagnosis of myophosphorylase deficiency was confirmed. The PCR-RFLP test is suitable for use in controlling this recessively-inherited disorder as it can diagnose heterozygous individuals that are otherwise clinically normal.  相似文献   
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Visible quantum cutting in LiGdF4:Eu3+ through downconversion   总被引:1,自引:0,他引:1  
For mercury-free fluorescent lamps and plasma display panels, alternative luminescent materials are required for the efficient conversion of vacuum ultraviolet radiation to visible light. Quantum cutting involving the emission of two visible photons for each vacuum ultraviolet photon absorbed is demonstrated in Eu3+-doped LiGdF4 with the concept of downconversion. Upon excitation of Gd3+ with a high-energy photon, two visible photons can be emitted by Eu3+ through an efficient two-step energy transfer from Gd3+ to Eu3+, with a quantum efficiency that approaches 200 percent.  相似文献   
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Modelling weed seedling emergence pattern appears to be a promising approach in the development of effective weed management programmes based on the selection of optimal timing of control operations. Thermal and hydrothermal time models propose that seed germination rates are proportional to the amount by which temperature and water potential exceed threshold values for these environmental factors. Hence, base temperature for seed germination is a fundamental biological parameter for the prediction of weed emergence. A series of laboratory experiments were conducted to estimate base temperature in three weed species belonging to the Asteraceae family, predominant in conservation tillage fields in north‐eastern Italy. The traditional method based on germination assays at constant temperatures was compared with a method based on assays at alternating temperatures. The latter might represent an alternative to the former for those species which do not germinate or only poorly under constant temperatures. Base temperature was estimated by regressing the reciprocal of the median germination time on temperature comparing two functions, a broken‐stick and an exponential‐type model. Both models showed good fit to all data in the whole temperature range and in almost all cases provided similar estimates of base temperature. The main result is that, for the weed species examined in this study, the use of alternating temperatures for base temperature estimation appears to be possible. However, further research is required to test if the use of germination assays performed at alternating temperatures can be a suitable method to estimate base temperature of species that have too low germination at constant temperatures.  相似文献   
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SnakeMap is a national cloud-based, veterinary snakebite registry. It was designed to prospectively collect data of the clinical circumstances and temporospatial information on cases of snake envenomation in dogs and cats. We herein introduce the project and summarise the data from the first 4 years of SnakeMap. The registry is a veterinary community-based online database allowing case entry from veterinary hospitals across Australia. Registry data comprise hospital characteristics, patient characteristics, envenoming snake type, treatment and outcome variables, including time and geolocation of the snake bite. We present summative information on select key variables from the SnakeMap registry (1 July 2015 to 30 June 2019). Twenty-eight hospitals from 6 states/territories entered 624 cases into the registry, including 419 dogs (67%) and 205 cats (33%). Bite time was available in 216 animals of which 90 (42%) were reported to be bitten in the 3 hours between 03:00 pm and 05:59 pm; median bite to presentation interval was 60 (interquartile range [IQR] 30, 211) minutes in dogs and 95 (IQR 41, 238) minutes in cats. Bites occurred in the owner's yard in 356 dogs (85%) and 53 cats (26%). A snake venom detection kit was used in 172 cases (28%) and antivenom was administered in 523 cases (85%). Most animals (n = 534, 88%) survived to discharge (median hospitalisation of 25 [IQR 16, 62] hours). SnakeMap effectively collects relevant clinical data from dogs and cats with presumed snake bite and provides locally specific information on the epidemiology of snake envenomation in small animals.  相似文献   
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