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111.
Karen O. Mathews Cathie Savage Jacqueline M. Norris David Phalen Nick Malikides Paul A. Sheehy Katrina L. Bosward 《Zoonoses and public health》2023,70(1):69-80
Australian wildlife rehabilitators (AWR) are at increased risk of developing Q fever, a serious zoonotic disease caused by the intracellular bacterium Coxiella burnetii. Previous studies have suggested that Australian wildlife may be a potential C. burnetii infection source for humans. However, a recent serological survey of AWR found no association between C. burnetii exposure and direct contact with any wildlife species. To further explore the potential risk that wildlife may pose, this study aimed to identify associations between self-reported Q fever in AWR and risk factors for exposure to C. burnetii. An online cross-sectional survey was implemented in 2018 targeting AWR nationwide. Risk factors for self-reported Q fever were determined using multivariable logistic regression. Medically diagnosed Q fever was self-reported in 4.5% (13/287) of unvaccinated respondents. Rehabilitators who self-reported medically diagnosed Q fever were significantly more likely to: primarily rehabilitate wildlife at a veterinary clinic (OR 17.87, 95% CI: 3.09–110.92), have domestic ruminants residing on the property where they rehabilitate wildlife (OR 11.75, 95% CI: 2.91–57.42), have been educated at a High School/Technical and Further Education level (OR 10.29, 95% CI: 2.13–84.03) and be aged >50 years (OR 6.61, 95% CI: 1.60–38.35). No association was found between self-reported Q fever and direct contact with wildlife. These findings support previous work suggesting that AWR are at increased risk of C. burnetii infection and may develop Q fever potentially via exposure to traditional infection sources including livestock, other domestic animals, or contaminated environments, in association with their rehabilitation practices and lifestyle. Although Q fever vaccination is recommended for AWR, vaccine uptake is low in this population. Future studies should aim to determine the level of Q fever awareness and identify barriers to Q fever vaccination in this at-risk group. The difficulty in accessing the AWR population also highlights the need for a national centralized AWR database. 相似文献
112.
Crop growth models have been used in simulating the soil water balance for purposes of irrigation management and yield predictions.
The application of CropSyst, a cropping systems simulation model, was evaluated for Cedara, South Africa. Simulations included
soil water balance of fallow land and rainfed and irrigated winter crops [oats (Avena sativa), Italian ryegrass (Lolium multiflorum) and rye (Secale cereale)]; and irrigation scheduling of the winter crops. Soil, plant, weather and management inputs were used for the soil water
balance simulations. Model crop parameters were used from past experiments or obtained from model documentation, with a slight
modification to account for varietal differences. The fallow land soil water simulations were more accurate for dry than for
wet soil. For all three winter crops, the model consistently over-estimated the soil water content in the upper layers, with
a good agreement for the deeper layers until a large precipitation event occurred to which the model responded more slowly
than that observed. Simulations using model-scheduled irrigation based on 0.4 and 0.6 maximum allowable depletion criteria
indicated that the observed applied irrigation in the field was more than that required. Soil water depletion and accumulated
transpiration simulations were similar in both the observed and model-scheduled irrigations, but total soil evaporation and
percolation were greater in the case of the observed than the model-scheduled irrigations. Irrigation scheduling using crop
growth models may assist in avoiding over- or under-application of irrigation applications by ensuring efficient utilization
of rain and irrigation. 相似文献
113.
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115.
Summary The indigenous Maori people quickly adopted early introductions of potatoes into New Zealand. These early cultivars known
as Maori Potatoes are smaller in size and differently coloured when compared to modern potato cultivars and are thought to
have remained unselected. The glycoalkaloid content of tubers ranged from 38.7 to 142.6 mg kg−1 (mean 76.5). A taste test conducted on 10 different cultivars showed that they were generally well accepted; however all
panellists noted a slightly bitter after taste in some of the cultivars. The texture and flavour were within acceptable limits
for all the cultivars tested. 相似文献
116.
Guillermo Velo-Antón David Rodríguez Anna E. Savage Gabriela Parra-Olea Karen R. Lips Kelly R. Zamudio 《Biological conservation》2012,146(1):213-218
Emergent infectious diseases are a severe threat to global biodiversity, thus conservation biologists need to understand the emergence, spread, and evolution of pathogens to identify factors driving disease outbreaks. Amphibian chytridiomycosis is a recently emerged amphibian disease caused by the fungus Batrachochytrium dendrobatidis (Bd) that has led to species extinctions and declines worldwide. The spatio-temporal dynamics of pathogen occurrence and disease outbreaks, and comparative genomic analyses of global Bd strains, support the spreading pathogen hypothesis (SPH) with pandemics occurring after introduction of Bd into naïve host populations. Here we used population genetics of the amphibian-killing fungus to test for genetic consequences of pathogen spread. Our population genetic analyses are consistent with the spread of Bd from North to Central America, based on low genetic diversity, reduction in heterozygosity, and increased allele fixation in Bd from recently infected populations. Our findings confirm the spread of Bd in the New World, and indicate that future conservation efforts should focus on: (i) functional consequences (such as changes in pathogenicity) of these genetic changes, and (ii) public education and restrictions on wildlife trade to help slow spread of the pathogen at the invasion front. 相似文献
117.
Hussain K Challis B Rocha N Payne F Minic M Thompson A Daly A Scott C Harris J Smillie BJ Savage DB Ramaswami U De Lonlay P O'Rahilly S Barroso I Semple RK 《Science (New York, N.Y.)》2011,334(6055):474
Pathological fasting hypoglycemia in humans is usually explained by excessive circulating insulin or insulin-like molecules or by inborn errors of metabolism impairing liver glucose production. We studied three unrelated children with unexplained, recurrent, and severe fasting hypoglycemia and asymmetrical growth. All were found to carry the same de novo mutation, p.Glu17Lys, in the serine/threonine kinase AKT2, in two cases as heterozygotes and in one case in mosaic form. In heterologous cells, the mutant AKT2 was constitutively recruited to the plasma membrane, leading to insulin-independent activation of downstream signaling. Thus, systemic metabolic disease can result from constitutive, cell-autonomous activation of signaling pathways normally controlled by insulin. 相似文献
118.
Robert J. Newman Kimberly M. Egeler Amanda L. Conkling Mason Y. Savage 《Veterinary radiology & ultrasound》2020,61(5):E40-E44
A 5‐year‐old spayed female English Bulldog was evaluated for acute anorexia, lethargy, respiratory distress, and syncope. Contrast‐enhanced computed tomography revealed the vascular malformation of azygous continuation of the caudal vena cava with extensive thrombus formation and pulmonary arterial thromboembolic disease. The patient was hospitalized for supportive treatment and was prescribed long‐term clopidogrel therapy. The patient survived to discharge and at last follow‐up remained clinically stable. While this vascular malformation has been reported in canines, to the authors’ knowledge, this is the first reported case of pulmonary thromboembolic disease in a canine concurrent with this condition. 相似文献
119.
In this paper, a new uterine discharge index (D‐index) was created and tested. It was based on a principal component analysis (PCA) of clinical findings of classical uterine discharge symptoms and rectal temperature during the postpartum period of dairy cattle. The PCA analysis revealed how uterine discharge features relate to each other and how they cluster together possibly representing different degrees of uterine inflammation. The D‐index was the result of the multivariate PCA‐analysis, and the D‐index gives a continuous value between 0 and 10. It was demonstrated that the same scale, i.e. the D‐index, can be used without any adjustment from 1 to 6 weeks post‐calving. It is valid for any type of uterine discharge without defining the type of infection or differentiating between infection and contamination. The D‐index was tested using the uterine involution data. Uterine involution was significantly delayed in the high‐D‐index group of cows. Similarly, in the test with all cows, involution was progressively delayed and the rate of involution of the pregnant horn was slowed down with the increase of the D‐index values. It is concluded that the D‐index can be a new practical, universal, tool for improved management of dairy cows in the postpartum period under commercial conditions. 相似文献
120.
R136 (HD 38268) is the central object of the 30 Doradus Nebula, a giant region of ionized hydrogen in the Large Magellanic Cloud. Observations of R136 at low and high spectral resolution with the International Ultraviolet Explorer reveal a peculiar hot object with a massive stellar wind. An outflow speed of 3500 kilometers per second and a temperature of approximately 60,000 K are indicated by the spectra. The bulk of the observed ultraviolet radiation must come from R136a, the brightest and bluest component of R136. Its absolute visual magnitude and observed temperature imply a luminosity about 10(8) times that of the sun. Most of the ionizations produced in 30 Doradus are provided by this peculiar object. If RI36a is a dense cluster of very hot stars, about 30 stars of classes O3 and WN3 exist in a region estimated to have a diameter of less than 0.1 parsec. This is inconsistent with the ultraviolet line spectrum and the evidence for optical variability. An alternative interpretation of the observations is that the radiation from R136a is dominated by a single superluminous object with the following approximate properties: luminosity and temperature as given above, a radius 100 times that of the sun, a mass 2500 times that of the sun, and a loss rate of 10(-3.5) solar masses per year. Model interior calculations for hydrogen-burning stars are consistent with these parameters. Such stars, however, are expected to be unstable, and this may account for the massive stellar wind. 相似文献