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81.
美国食品工业正处在一个转折点,即如何生产和销售健康食品。据加州大学戴维斯分校哲学博士布鲁斯教授介绍,“未来的食品不仅要求更加健康,同时要求更容易被人接受。食品安全、便利甚至外形将会日益个性化。”布鲁斯教授称,“应该考虑食用什么食品对自身健康有利。健康不只是脱离疾病,它还可以保证我们的生活质量,使我们获得运动、认知的能力,  相似文献   
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Aquaculture production and invasive species are intricately linked. Invasives enter waterways threatening production, increasing costs, and diminishing grower returns. Live plants and animals introduced for economic production escape their confines and establish in the wild. This paper provides an overview of the dominant issues illustrated with cases from around the world.  相似文献   
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BACKGROUND: Glyphosate resistance has been confirmed in 58 populations of Lolium rigidum (Gaud.), a major weed of crops in southern Australia. Extensive use of glyphosate in conjunction with minimal soil disturbance has been identified as high risk for resistance to that herbicide. Land managers need a simple method for rapid assessment of the risk of resistance occurring as a result of past and proposed future management practices. Modelled on risk assessment nomographs, a simple calculator for indicating the risk of evolved glyphosate resistance in L. rigidum is described. RESULTS: The calculator uses the generations since first use and the frequency of use of glyphosate in combination with historical cultivation levels as critical factors for determining the risk of glyphosate resistance evolution. Based on the management history of a field, a land manager can graphically determine a glyphosate resistance risk for that field. CONCLUSION: The calculator enables the farmer or the advisor to assess the risk of a weed's population becoming resistant and modify practices accordingly to manage for sustainable glyphosate use. The risk calculator could be modified for other herbicides and different weed species.  相似文献   
85.

Objective

The effect of user experience and inflation technique on endotracheal tube cuff pressure using a feline airway simulator.

Study design

Prospective, experimental clinical study.

Methods

Participants included veterinary students at the beginning (group S1) and end (group S2) of their 2-week anaesthesia rotation and veterinary anaesthetists (group A). The feline airway simulator was designed to simulate an average size feline trachea, intubated with a 4.5 mm low-pressure, high-volume cuffed endotracheal tube, connected to a Bain breathing system with oxygen flow of 2 L minute?1. Participants inflated the on-endotracheal tube cuff by pilot balloon palpation and by instilling the minimum occlusive volume (MOV) required for loss of airway leaks during manual ventilation. Intracuff pressures were measured by manometers obscured to participants and ideally were 20–30 cm H2O. Student t, Fisher exact, and Chi-squared tests were used where appropriate to analyse data (p < 0.05).

Results

Participants were 12 students and eight anaesthetists. Measured intracuff pressures for palpation and MOV, respectively, were 19 ± 12 and 29 ± 19 cm H2O for group S1, 10 ± 5 and 20 ± 11 cm H2O for group S2 and 13 ± 6 and 29 ± 18 cm H2O for group A. All groups performed poorly at achieving intracuff pressures within the ideal range. There was no significant difference in intracuff pressures between techniques. Students administered lower (p = 0.02) intracuff pressures using palpation after their training.

Conclusions and clinical relevance

When using palpation and MOV for cuff inflation operators rarely achieved optimal intracuff pressures. Experience had no effect on this skill and, as such, a cuff manometer is recommended.  相似文献   
86.
In an effort to increase suicide awareness skills among veterinary undergraduates, a three-hour suicide awareness workshop (safeTALK) was delivered to third-year Royal (Dick) School of Veterinary Studies undergraduates as part of their professional development curriculum. Students were able to opt out of the session by contacting the course organisers. A total of 26 of 151 (17 per cent) third-year students attended the workshop, and 17 completed a feedback questionnaire. The vast majority of the students reported that after completing the workshop they were more likely or much more likely to recognise the signs of a person at risk of suicide, approach a person at risk of suicide, ask a person about suicide, and connect a person at risk of suicide with help. Five veterinary academics attended a two-day Applied Suicide Intervention Skills Training (ASIST) course, and all reported that the course was effective in improving suicide awareness and intervention skills.  相似文献   
87.
Rabies is an incurable zoonotic disease caused by rabies virus, a member of the rhabdovirus family. It is transmitted through the bite of an infected animal. Control methods, including oral rabies vaccination (ORV) programs, have led to a reduction in the spread and prevalence of the disease in wildlife. This study evaluated the stability of RABORAL, a recombinant vaccinia virus vaccine that is used in oral rabies vaccination programs. The vaccine was studied in various field microenvironments in order to describe its viability and facilitate effective baiting strategies. Field microenvironments influenced the stability of this vaccine in this study. This study emphasizes the importance of understanding how vaccines perform under varying field conditions in order to plan effective baiting strategies.  相似文献   
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Methylcyclopentadienyl manganese tricarbonyl (MMT) was used between 1990 and 2003 as an antiknock agent and as an octane booster in Canadian unleaded gasoline. Its combustion leads to Mn emissions. The objective of this research was to examine the variations in atmospheric Mn in Montreal (Canada) from 2001 to 2007, covering the period prior (2001?C2003) to and following (2005?C2007) MMT use. Three sampling stations were selected because of their proximity to roads with widely differing and well-known traffic patterns. Filters from 2001 to 2007 were obtained from the Montreal Urban Community. The first sample of each month was selected, and Mn analysis was performed by neutron activation analysis. Total suspended particulates (TSP) was calculated by weighing the filters before and after dust collection. Results show a significant decrease of Mn over time at each station, whereas TSP decreased significantly in two stations. Comparing atmospheric Mn during and after the period of use of MMT 2001?C2003 vs 2005?C2007 showed a significant decrease at all stations. For TSP, only one station showed borderline significant decline between these two periods. Overall, between the two periods, Mn and TSP decreased by 39% and 17%, respectively. These data suggest that the combustion of MMT led to an increase of airborne Mn of approximately 22%. These findings should help in decision-making processes concerning the use of MMT in gasoline in other countries.  相似文献   
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