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111.
Climate change and violent conflict 总被引:2,自引:0,他引:2
Scheffran J Brzoska M Kominek J Link PM Schilling J 《Science (New York, N.Y.)》2012,336(6083):869-871
Current debates over the relation between climate change and conflict originate in a lack of data, as well as the complexity of pathways connecting the two phenomena. 相似文献
112.
AJ DART N PERKINS BA DOWLING T BATTERHAM C LIVINGSTON DR HODGSON 《Australian veterinary journal》2001,79(9):624-627
OBJECTIVE: To evaluate the effects of three different doses of sodium pentosan polysulphate (PPS) on haematological and haemostatic variables in adult horses. DESIGN: Eight adult standardbred horses were used. All horses received a single injection of 0, 3, 6, and 10 mg/kg of PPS at the beginning of each treatment week for 4 weeks so that by the end of the study all horses had received all four doses of PPS. Blood samples were collected at 0, 1, 2, 3, 4, 6, 8, 12, 24, 48, and 168 h after each weekly injection of PPS. Variables measured were packed cell volume, haemoglobin, red blood cell count, mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration, platelet count, white cell count, neutrophil count, lymphocyte count, eosinophil count, monocyte count, serum protein, fibrinogen, prothrombin time, and activated partial thromboplastin time (PTT). Data were analysed using an ANOVA. Significance was set at P < 0.05. RESULTS: There was a dose-dependent increase in PTT. A significant increase in PTT occurrred in all treatment groups when compared to horses receiving 0 mg/kg in which there was no change over time. The PTT values all returned to baseline by 48 h after treatment. The mean neutrophil count was higher 3 h after treatment when compared to time 0. Horses receiving 3 mg/kg of PPS had a higher lymphocyte count 4 h after injection, and those receiving 6 and 10 mg/kg had higher counts at 3,4,6 and 8 h after injection when compared to time 0. At 8 h after injection horses receiving 6 and 10 mg PPS had higher lymphocyte counts than horses not receiving PPS. CONCLUSIONS: PPS causes a dose-dependent prolongation of PTT in horses. At the dose rates currently recommended for treatment of joint problems in horses this increase was small and remained elevated from baseline for up to 24 h. Based on these findings doses of PPS up to 3 mg/kg should not be administered to horses within 24 h of high stress activities or where physical injury may occur. 相似文献
113.
L. Gaschen DVM DR. Med. Vet. PhD P. Kircher DR. Med. Vet. G. Hoffmann DR. Med. Vet. N. Luckschander DR. Med. Vet. H. Schmoekel DR. Med. Vet. D. Spreng DR. Med. Vet. J. Lang PD DR. Med. Vet. 《Veterinary radiology & ultrasound》2003,44(3):292-299
Endoscopic ultrasound was developed initially in humans to overcome limitations of conventional ultrasound in examining certain internal organs due to intervening bone or air-filled structures. Endoscopic ultrasound has been used most widely in investigation of the gastrointestinal tract in humans, but many intrathoracic applications as well as endoscopic ultrasound-guided techniques have recently been described. Mediastinal and pulmonary structures can be examined with endoscopic ultrasound since a high frequency ultrasound probe can be brought into close contact with the areas of interest via a transesophageal approach. The purpose of this report is to describe the application of endoscopic ultrasound as an aid in the diagnosis of intrathoracic disease in the dog. Two dogs, one with a history of prior esophageal foreign body extraction, the other with apathy, weakness and dyspnea were referred for further investigation. Both dogs had caudal intrathoracic soft tissue opacities diagnosed radiographically, but their origin and nature were difficult to determine. Conventional ultrasound was limiting in both dogs due to their location and superimposition of gas-filled structures. With endosonography lesions were characterized more completely. We have found endoscopic ultrasound to be an elegant diagnostic tool for the investigation of radiographically detected intrathoracic lesions in the dog whose origins are difficult to determine or do not lend themselves to investigation by conventional ultrasound. Endoscopic ultrasound provides valuable diagnostic information complementary to that provided radiographically which aids in therapeutic planning. Endoscopic ultrasound was also more sensitive for detecting mediastinal lymphadenomegaly than radiography in one of the dogs. An additional advantage of endoscopic ultrasound is the fact that US-guided tissue sampling can be performed during the examination. 相似文献
114.
Faba bean is a partially allogamous grain legume, mostly sown as spring crop in Central Europe, and in few mild coastal areas
of UK and France as a winter crop. A population with a genetically wide base, conceived and selected for superior winter hardiness
showing promise as winter crop in Germany was evaluated. The reproductive behaviour of this population was evaluated for its
degree of cross-fertilization at five German environments (1999–2001), and inbred lines bred from it, plus one F1 bulk and
further checks, were assessed for variation in cross-fertilization at three German environments (2001). Seed hilum colour,
a dominant-recessive, biallelic locus, was used as a morphological marker. Cross-fertilization (population mean value of 60%)
was shown to be higher than in spring faba beans and was environmentally influenced. Genetic variation was demonstrated, heritability
was high (h2= 0.75), and heterosis was negative. Inbred lines with a cross-fertilization of 70% can be easily bred. Breeding synthetic
cultivars is recommended, their optimum number of components is expected to be higher than the optimum recommended for spring
faba beans.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
115.
Laurent S. Garosi DVM Ruth Dennis MA VetMB Tobias Schwarz MA DR Med Vet 《Veterinary radiology & ultrasound》2003,44(2):137-146
Diagnostic imaging techniques (conventional radiography, computed tomography and magnetic resonance imaging) are an essential tool in the diagnostic work-up of ear diseases. Conventional radiography is commonly used, but often lacks sensitivity. Computed tomography (CT) and magnetic resonance (MR) are complementary imaging studies of the middle ear, labyrinth, internal auditory canal and their contents. CT provides excellent images of bony structures and is indicated where osseous changes are of greatest diagnostic importance. MR is superior in imaging soft tissue components including intralabyrinthine fluid. Therefore, more than one of these imaging techniques may be required in order to make a diagnosis. 相似文献
116.
RF Cooper JB Fanselow JKR Weber DR Merkley DB Poker 《Science (New York, N.Y.)》1996,274(5290):1173-1176
Rutherford backscattering spectroscopy (RBS) and microscopy demonstrate that the approximately 1400°C oxidation of levitated droplets of a natural Fe2+-bearing aluminosilicate (basalt) melt occurs by chemical diffusion of Fe2+ and Ca2+ to the free surface of the droplet; internal oxidation of the melt results from the required counterflux of electron holes. Diffusion of an oxygen species is not required. Oxidation causes the droplets to go subsolidus; magnetite (Fe3O4) forms at the oxidation-solidification front with a morphology suggestive of a Liesegang-band nucleation process. 相似文献
117.
118.
Walba DM Korblova E Shao R Maclennan JE Link DR Glaser MA Clark NA 《Science (New York, N.Y.)》2000,288(5474):2181-2184
We describe the design and synthesis of a ferroelectric liquid crystal composed of racemic molecules. The ferroelectric polarization results from spontaneous polar symmetry breaking in a fluid smectic. The ferroelectric phase is also chiral, resulting in the formation of a mixture of macroscopic domains of either handedness at the isotropic-to-liquid crystal phase transition. This smectic liquid crystal is thus a fluid conglomerate. Detailed investigation of the electrooptic and polarization current behavior within individual domains in liquid crystal cells shows the thermodynamically stable structure to be a uniformly tilted smectic bow-phase (banana phase), with all layer pairs homochiral and ferroelectric (SmC(S)P(F)). 相似文献
119.
Common mechanism of chromosome inversion in B- and T-cell tumors: relevance to lymphoid development 总被引:12,自引:0,他引:12
C T Denny G F Hollis F Hecht R Morgan M P Link S D Smith I R Kirsch 《Science (New York, N.Y.)》1986,234(4773):197-200
An inversion of chromosome 14 present in the tumor cells of a patient with childhood acute lymphoblastic leukemia of B-cell lineage was shown to be the result of a site-specific recombination event between an immunoglobulin heavy-chain variable gene and the joining segment of a T-cell receptor alpha chain. This rearrangement resulted in the formation of a hybrid gene, part immunoglobulin and part T-cell receptor. Furthermore, this hybrid gene was transcribed into messenger RNA with a completely open reading frame. Thus, two loci felt to be normally activated at distinct and disparate points in lymphocyte development were unified and expressed in this tumor. 相似文献
120.
Megan D. Higgs William A. Link Gary C. White Mark A. Haroldson Daniel D. Bjornlie 《Journal of Agricultural, Biological & Environmental Statistics》2013,18(4):556-577
Mark-resight designs for estimation of population abundance are common and attractive to researchers. However, inference from such designs is very limited when faced with sparse data, either from a low number of marked animals, a low probability of detection, or both. In the Greater Yellowstone Ecosystem, yearly mark-resight data are collected for female grizzly bears with cubs-of-the-year (FCOY), and inference suffers from both limitations. To overcome difficulties due to sparseness, we assume homogeneity in sighting probabilities over 16 years of bi-annual aerial surveys. We model counts of marked and unmarked animals as multinomial random variables, using the capture frequencies of marked animals for inference about the latent multinomial frequencies for unmarked animals. We discuss undesirable behavior of the commonly used discrete uniform prior distribution on the population size parameter and provide OpenBUGS code for fitting such models. The application provides valuable insights into subtleties of implementing Bayesian inference for latent multinomial models. We tie the discussion to our application, though the insights are broadly useful for applications of the latent multinomial model. 相似文献