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A cross-sectional study was conducted at the height of the pandemic influenza H1N1/09 outbreak in Australia in 2009. The objectives of the study were to evaluate public perceptions about transmission and prevention of the disease, to understand their concerns and preparedness to cope with the disease, and to investigate drivers influencing their behaviour. A questionnaire was designed and administered to 510 customers visiting 15 butcher shops in the Greater Sydney region between 26th June and 2nd August 2009. Data were analysed to estimate the proportion of people with certain perceptions and to evaluate the influence of these perceptions on two binary outcome variables: (1) whether or not people believed that avoiding pork would protect them from contracting H1N1/09, and (2) whether or not they actually made some changes to pork consumption after the outbreak. A majority of the respondents had perceptions based on fact about transmission and prevention of H1N1/09. As many as 96.8% of the respondents believed that washing their hands frequently was likely to protect them from contracting H1N1/09. Similarly, most believed that they could contract H1N1/09 by travelling on public transport with a sick person present (94.1%), by shaking hands with a sick person (89.2%), or by attending a community gathering (73.7%). Women were more likely than men to have factual perceptions about protective behaviours. Misconceptions regarding transmission of the disease were evident, with 21.7% believing that avoiding eating pork could protect them against H1N1/09, 11.1% believing that they could contract H1N1/09 by drinking tap water, 22.8% by handling uncooked pork meat and 15.6% by eating cooked pork. Approximately one third of respondents believed that working in a pig farm or an abattoir increased their likelihood of contracting H1N1/09 (36.9% and 32.3%, respectively). Younger people (<35 years old) were more likely to have these misconceptions than older people. Reduction in consumption of pork, ham or bacon was significantly associated with misconceptions regarding the risk of contracting H1N1/09 from eating pig meat products. It is recommended that in the event of a future disease emergency, communication activities providing factual information and targeting younger people should be used. 相似文献
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Sylwia Dobrzeniecka Kabwe K. Nkongolo Paul Michael Melanie Mehes-Smith Peter Beckett 《Water, air, and soil pollution》2011,215(1-4):117-125
Genetic variation and genetic structure of black spruce (Picea mariana L.) populations growing in wet land (lowlands) and dry lands (uplands) with different levels of metal contaminations were analyzed using ISSR. Polymorphic loci (P%) ranged from 65% to 90% with a mean of 75%. Nei??s gene diversity (h) varied from 0.264 to 0.359 with a mean of 0.310, and Shannon??s index (I) ranged from 0.381 to 0.524 with a mean of 0.449. The level of genetic variation was higher in populations from wet lands than those from dry lands. Variation within populations accounts for most of total genetic variation. The genetic distance among the black spruce (P. mariana) populations ranged from 0.171 to 0.351. The present study indicates that genetic variation and long-term exposure to metals (more than 30 years) are not associated. Cytological analysis of black spruce seeds from metal-contaminated and -uncontaminated areas showed normal mitotic behavior during prophase, metaphase, anaphase, and telophase. 相似文献
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A simple and rapid method for the determination of naturally occurring, potentially hazardous glycoalkaloids (GAs) in potatoes
and their products has been developed. The procedure is based on the on-line solid-phase extraction of the acetic acid extracts
from potato products and combined with liquid chromatography (LC)-mass spectrometry (MS) in a fully automated system (Symbiosis™,
Spark Holland Instruments, Emmen, The Netherlands). As sorbent material HySphere™ 18HD was used for alkaloid enrichment. GAs
were eluted with the LC gradient and directly analysed by MS. Detection of the analytes was achieved in the sensitive multiple
reaction monitoring mode using two characteristic ions (m/z 98 as a qualifier for GAs and m/z 868.3 as a quantifier for α-solanine or m/z 852.4 for α-chaconine). Typical validation data for method precision (v
k α-solanine = 5.3–6.5, v
k α-chaconine = 3.4–15.4), accuracy (average recovery of α-solanine = 84%, average recovery of α-chaconine = 87%) and linearity
over the range from 1 to 1,000 ng ml−1 (R
2 = 0.9915 for α-solanine, R
2 = 0.9939 for α-chaconine) with detection limits of 0.3 ng ml−1 for α-chaconine and 0.5 ng ml−1 for α-solanine were obtained. GA contents of commercial potato products were determined by the new on-line method and afterwards
compared with those obtained with an established high-performance LC routine procedure. Better performance of the on-line
procedure was obvious from the standard deviations of both methods. Other advantages included a strong reduction of overall
analysis time, human intervention and solvent consumption as well as waste production. The time required for the on-line analysis
was 5 min, which would allow processing of almost 100 samples in 8 h. 相似文献
68.
Fijen Thijs P. M. Read Samantha F. J. Walker Melanie K. Gee Megan Nelson Warrick R. Howlett Brad G. 《Landscape Ecology》2022,37(7):1787-1799
Landscape Ecology - Landscape simplification is a main driver of insect decline, threatening crop pollination services. Changes in functional features in simplified agroecosystems may impact the... 相似文献
69.
Boly M Garrido MI Gosseries O Bruno MA Boveroux P Schnakers C Massimini M Litvak V Laureys S Friston K 《Science (New York, N.Y.)》2011,332(6031):858-862
Frontoparietal cortex is involved in the explicit processing (awareness) of stimuli. Frontoparietal activation has also been found in studies of subliminal stimulus processing. We hypothesized that an impairment of top-down processes, involved in recurrent neuronal message-passing and the generation of long-latency electrophysiological responses, might provide a more reliable correlate of consciousness in severely brain-damaged patients, than frontoparietal responses. We measured effective connectivity during a mismatch negativity paradigm and found that the only significant difference between patients in a vegetative state and controls was an impairment of backward connectivity from frontal to temporal cortices. This result emphasizes the importance of top-down projections in recurrent processing that involve high-order associative cortices for conscious perception. 相似文献
70.
Karol A. Mathews DVM DVSc Melanie J. Brooks RVT Anne E. Valliant BSC 《Journal of Veterinary Emergency and Critical Care》1996,6(1):33-43
A one year prospective study was conducted to determine the association between intravenous catheter contamination and increased dwell time, and to identify any related risk factors. Intravenous catheters obtained from 23 cats and 98 dogs in the Intensive Care Unit at the Ontario Veterinary College with dwell times > 72 hours for the test group (n=58) and < 72 hours for a corresponding control group (n=63) were cultured between April 1991 and March 1992. One hundred and twenty one catheters were cultured, 16 jugular, 99 cephalic, and 6 saphenous. The overall contamination rate was 13 out of 121 catheters cultured (10.7%); 9/63 (14.3%) control and 4/58 (6.9%) test catheters. The bacteria isolated were E.aerogenes, S.aureus (3), P.aeruginosa, P.multocida, and Bacillus sp (7). The Bacillus sp positive catheters (5 control and 2 test) were placed during a five day period, and contaminated gauze squares were identified as the source of infection in these catheters. After these were removed from the study, the group infection rate was 6.9% control and 3.6% test. There was no significant difference between groups and no associated risk factors were identified. We conclude that intravenous dwell time need not be restricted to <72 hours. 相似文献