64 resultados para wildfire suppression


Relevância:

30.00% 30.00%

Publicador:

Resumo:

During large scale wildfires, suppression activities are carried out under the direction of an Incident Management Team (IMT). The aim of the research was to increase understanding of decision processes potentially related to IMT effectiveness. An IMT comprises four major functions: Command, Operations, Planning, and Logistics. Four methodologies were used to study IMT processes: computer simulation experiments; analyses of wildfire reports; interviews with IMT members; and cognitive ethnographic studies of IMTs. Three processes were important determinants of IMT effectiveness: information management and cognitive overload; matching component function goals to overall goals; and team metacognition to detect and counter task-disruptive developments. These processes appear to be complex multi-person analogues of individual Incident Command processes identified previously. The findings have implications for issues such as: creating IMTs; training IMTs; managing IMTs; and providing decision support to IMTs.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The purpose of this study was to examine 1) wildfire fighters' ability to consume the prescribed fluid volume (1200 mL h-1), 2) the effect of fluid intake on plasma sodium and hydration, and 3) the effect of fluid intake on firefighters' heart rate, core temperature and activity during emergency suppression shifts. Methods: Thirty-four firefighters were divided into ad libitum (AD, n = 17) and prescribed (PR, n = 17) drinking groups. Results: PR drinkers did not meet the prescribed fluid target, yet consumed over double the volume of AD drinkers. No differences between groups in plasma sodium or hydration were noted. PR drinking resulted in lower core temperature between 2 and 6 h. This did not coincide with reduced cardiovascular strain, greater work activity or larger distances covered when compared to AD drinkers. Conclusion: Extra fluid consumption (above AD) did not improve firefighter activity or physiological function (though PR firefighters core temperature was lower earlier in their shift). Firefighter can self-regulate their fluid consumption behavior and work rate to leave the fireground euhydrated.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Purpose Zinc sulfate is known to inhibit the bitterness of the antimalarial agent quinine [R. S. J. Keast. The effect of zinc on human taste perception. J. Food Sci. 68:1871–1877 (2003)]. In the present work, we investigated whether zinc sulfate would inhibit other bitter-tasting compounds and pharmaceuticals. The utility of zinc as a general bitterness inhibitor is compromised, however, by the fact that it is also a good sweetness inhibitor [R. S. J. Keast, T. Canty, and P. A. S. Breslin. Oral zinc sulfate solutions inhibit sweet taste perception. Chem. Senses 29:513–521 (2004)] and would interfere with the taste of complex formulations. Yet, zinc sulfate does not inhibit the sweetener Na-cyclamate. Thus, we determined whether a mixture of zinc sulfate and Na-cyclamate would be a particularly effective combination for bitterness inhibition (Zn) and masking (cyclamate).

Method We used human taste psychophysical procedures with chemical solutions to assess bitterness blocking.

Results Zinc sulfate significantly inhibited the bitterness of quinine–HCl, Tetralone, and denatonium benzoate (DB) (p < 0.05), but had no significant effect on the bitterness of sucrose octa-acetate, pseudoephedrine (PSE), and dextromethorphan. A second experiment examined the influence of zinc sulfate on bittersweet mixtures. The bitter compounds were DB and PSE, and the sweeteners were sucrose (inhibited by 25 mM zinc sulfate) and Na-cyclamate (not inhibited by zinc sulfate). The combination of zinc sulfate and Na-cyclamate most effectively inhibited DB bitterness (86%) (p < 0.0016), whereas the mixture's inhibition of PSE bitterness was not different from that of Na-cyclamate alone.

Conclusion A combination of Na-cyclamate and zinc sulfate was most effective at inhibiting bitterness. Thus, the combined use of peripheral oral and central cognitive bitterness reduction strategies should be particularly effective for improving the flavor profile of bitter-tasting foods and pharmaceutical formulations.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Bitterness is an ongoing taste problem for both the pharmaceutical and food industries. This paper reports on how salts (NaCI, NaAcetate, NaGluconate, LiCI, KCI) and bitter compounds (urea, quinine-HCI, caffeine, amiloride-HCI, magnesium sulfate, KCI) interact to influence bitter perception. Sodium salts differentially suppress bitterness of these compounds; for example urea bitterness was suppressed by over 70% by sodium salts, while MgSO4 bitterness was not reduced. This study indicated that lithium ions had the same bitter suppressing ability as sodium ions, however the potassium cation had no bitter suppression ability. Changing the anion attached to the sodium did not affect bitter suppression, however, as the anion increased in size, perceived saltiness decreased. This indicates that sodium's mode of action is at the peripheral taste level, rather than a cognitive affect. A second experiment revealed that suppressing bitterness with a sodium salt in a bitter/sweet mixture causes an increase in sweetness. This suggests adding salt to a food matrix will not only increase salt perception, but also potentiate flavor by differential suppression of undesirable tastes such as bitter, while increasing more desirable tastes such as sweet.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Bovine viral diarrhea virus (BVDV) is a ubiquitous viral pathogen that affects cattle herds’ worldwide causing significant economic loss. The current strategies to control BVDV infection include vaccination (modified-live or killed) and control of virus spread by enhanced biosecurity management, however, the disease remains prevalent. With the discovery of the sequence-specific method of gene silencing known as RNA interference (RNAi), a new era in antiviral therapies has begun. Here we report the efficient inhibition of BVDV replication by small interfering (siRNA) and short hairpin RNA (shRNA)-mediated gene silencing. siRNAs were generated to target the 5′ non-translated (NTR) region and the regions encoding the C, NS4B and NS5A proteins of the BVDV genome. The siRNAs were first validated using an EGFP/BVDV reporter system and were then shown to suppress BVDV-induced cytopathic effects and viral titers in cell culture with surprisingly different activities compared to the reporter system. Efficient viral suppression was then achieved by bovine 7SK-expressed BVDV-specific shRNAs. Overall, our results demonstrated the use of siRNA and shRNA-mediated gene silencing to achieve efficient inhibition of the  replication of this virus in cell culture.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Abscisic acid (ABA) has been implicated in determining the outcome of interactions between many plants and their pathogens. We had previously shown that increased concentrations of ABA within leaves of Arabidopsis induced susceptibility towards an avirulent strain of Pseudomonas syringae pathovar (pv.) tomato. We now show that ABA induces susceptibility via suppression of the accumulation of components crucial for a resistance response. Lignin and salicylic acid concentrations in leaves were increased during a resistant interaction but reduced when plants were treated with ABA. The reduction in lignin and salicylic acid production was independent of the development of the hypersensitive response (HR), indicating that, in this host-pathogen system, HR is not required for resistance. Genome-wide gene expression analysis using microarrays showed that treatment with ABA suppressed the expression of many defence-related genes, including those important for phenylpropanoid biosynthesis and those encoding resistance-related proteins. Together, these results show that resistance induction in Arabidopsis to an avirulent strain of P. syringae pv. tomato is regulated by ABA.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Wildfires can induce or enhance soil water repellency under a range of vegetation communities. According to mainly USA-based laboratory studies, repellency is eliminated at a maximum soil temperature (T) of 280–400°C. Knowledge of T reached during a wildfire is important in evaluating post-fire soil physical properties, fertility and seedbed status. T is, however, notoriously difficult to ascertain retrospectively and often based on indicative observations with a large potential error. Soils under fire-prone Australian eucalypt forests tend to be water repellent when dry or moderately moist even if long unburnt. This study aims to quantify the temperature of water repellency destruction for Australian topsoil material sampled under three sites with contrasting eucalypt cover (Eucalyptus sieberi, E. ovata and E. baxteri). Soil water repellency was present prior to heating in all samples, increased during heating, but was abruptly eliminated at a specific T between 260 and 340°C. Elimination temperature varied somewhat between samples, but was found to be dependent on heating duration, with longest duration resulting in lowest elimination temperature. Results suggest that post-fire water repellency may be used as an aid in hindcasting soil temperature reached during the passage of a fire within repellency-prone environments.


Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper focuses on themes of emotionality and emotional labour derived inductively from retrospective narratives constructed by employees who experienced rapid organisational change and specifically addresses the question: 'How do people talk about the need to "dull down" their emotions during situations of organisational change?' We highlight themes of loss associated with retrospective displays of emotion and argue that loss and emotion management are most typically associated with issues concerning transition from the past or resistance to the future. We show how emotional labour serves both to mute and, ironically, to heighten emotions in the talk of change and extend studies of emotional labour beyond the service encounter and into the realm of organisational change.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Firefighting foams (Class A foams) are an effective and widespread firefighting tool which are frequently used in environmentally sensitive areas. Firefighting foams are known to be ecologically damaging in aquatic environments, however their impacts at the plant species or ecosystem level are relatively unknown. Reports of shoot damage to plants, suppressed flowering, and changes in plant community composition suggested that the ecological damage caused by their use may be unacceptable. However, applications of foam to seedlings of some Australian plant species from representative and widespread families, showed no detectable impacts on a range of vegetative growth characteristics. Application of 1.0% foam to heathland soils showed no detectable impacts on soil invertebrate Orders sampled over several months. The results are encouraging for the continued use of Class A foam as a fire suppression technique.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The phytohormone, abscisic acid (ABA) has been shown to influence the outcome of the interactions between various hosts with biotrophic and hemibiotrophic pathogens. Susceptibility to avirulent isolates can be induced in plants by addition of low physiological concentrations of ABA. In contrast, addition of ABA biosynthesis inhibitors induced resistance following challenge of plants by virulent isolates. ABA deficient mutants of Arabidopsis, such as aba1-1, were resistant to virulent isolates of Peronospora parasitica. In interactions of Arabidopsis with avirulent isolates of Pseudomonas syringae pv. tomato, susceptibility was induced following addition of ABA or imposition of drought stress. These results indicate a pivotal, albiet undefined, role for ABA in determining either susceptibility or resistance to pathogen attack. We have found that the production of the cell wall strengthening compound, lignin, is increased during resistant interactions of aba1-1 but suppressed in ABA-induced susceptible interactions. Using RT-PCR and microarray analysis we have found down-regulation by ABA of key genes of the phenylpropanoid pathway especially of those genes involved directly in lignin biosynthesis. ABA also down-regulates a number of genes in other functional classes including those involved in defence and cell signalling.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Purpose – The purpose of this paper is to explore the relationship between anti-money laundering (“AML”) and combating of financing of terrorism (“CFT”) customer due diligence (“CDD”) measures in the financial services industry, and exclusion from financial services.
Design/methodology/approach – An introduction to the concept of financial exclusion is provided as well as an overview of international AML/CFT CDD standards. The paper highlights a softening of national CDD measures in South Africa and the UK to lessen the impact on financial exclusion.
Findings – Countries should consider the impact that CDD requirements may have on financial exclusion when they design their AML/CFT systems.
Research limitations/implications – Multi-discilinary research is required to improve the understanding of the broader interaction between AML/CFT objectives, financial exclusion and economic development, especially in countries with a large informal economy.
Practical implications – CDD requirements may unnecessarily exacerbate financial exclusion if they are not formulated with care to reflect the reality of the particular country setting.
Originality/value – The paper offers insights into the international standards resulting to the identification of clients and the experiences in the UK and South Africa regarding the implementation of these standards on financial exclusion.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Stress compromises reproductive function and the major physiological system activated during stress is the hypothalamo-pituitary-adrenal axis. Corticotrophin-releasing hormone and arginine vasopressin (AVP), which are produced in neurones of the paraventricular nucleus (PVN), drive the hypothalamo-pituitary-adrenal axis and are also implicated in the suppression of the reproductive axis. We used retrograde tracing and Fos labelling to map the projections from the PVN to the preoptic area (POA) where most gonadotrophin releasing hormone (GnRH) neurones are found. Fluorogold (FG) injections were made into the POA of gonadectomised male and female sheep (n = 5/sex), the animals were stressed and the brains recovered for histochemistry. All animals responded to stress with an increase in the number of Fos-labelled nuclei in the PVN. Few retrogradely labelled cells of the PVN were activated by stress. Dual labelling showed that very few FG-labelled cells also stained for corticotrophin-releasing hormone, none for AVP or enkephalin. Dual labelling for FG and Fos in the bed nucleus of the stria terminalis (BNST) and the arcuate nucleus showed that no FG-labelled cells in the BNST and only few in the ARC were activated by stress. No sex differences were observed in the activation of FG-labelled cells in any of the nuclei examined. We conclude that, although cells of the PVN, BNST and/or arcuate nucleus may affect reproduction via the GnRH cells of the POA, this is unlikely to involve direct input to the POA. If cells of these regions are involved in GnRH suppression during stress, this may occur via interneuronal pathways.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Brooding rumination is associated with depressed mood, increased negative affect, prolonged anger and inhibited cardiovascular (CV) recovery. Distraction from rumination on a stressful interpersonal encounter is associated with faster CV recovery and decreased negative affect. Studies have suggested that a concurrent visuospatial (VS) task inhibits the maintenance of imagery associated with the perseveration of intrusive negative memories. 120 healthy participants were recruited for the study. As an analogue of repeated angry rumination, the authors explored the effects of repeated visual recall of a provocative confederate and the subsequent impact of two visuospatial (VS) distraction tasks on negative affect, blood pressure (BP) and heart rate (HR). Repeated recall of the provocation generated repeatedly elevated HR with a cumulative trend that may have CV disease risk implications for chronic ruminators. VS distraction did not aid recovery compared with the Control task.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Aching muscles and joints, lethargy, and sleepiness are all signs of firefighter fatigue during bushfire suppression. If not managed, fatigue may lead to injury or illness for the individual, which may also compromise the safety and productivity of their crew. Understanding the many sources of firefighter fatigue is, therefore, fundamental for all Australian fire agencies. This article will briefly address  several factors thought to contribute to firefighter fatigue including; sleep loss, firefighter’s work activity, their hydration, and nutrition, the hot and smoky  working environment, firefighter’s physical fitness and their experience. This brief overview draws on findings from firefighting research and the broader scientific literature.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background: Each year bushfire threatens Australia’s rural, forest, and urban-rural areas. Australia’s rural fire fighters work to curtail this threat in hot, smoky conditions, often at risk to their physical health. General practitioners, especially in rural areas, can help preserve the health of fire fighters during the fire season by understanding the stressors they face on the fireground.

Objective: This article outlines how the key fireground stressors of work intensity and duration, heat (from the weather, the fire, and the fire fighter’s own exertion) and smoke impact on the health of fire fighters. Practical advice for GPs treating Australia’s rural fire fighters is also included.

Discussion
: General practitioners can help preserve fire fighters' health during bushfire suppression in a number of ways, including: identifying fire fighters at risk of cardiac distress during physical labour and educating them about the early warning signs; advocating regular exercise; discouraging smoking; and promoting the benefits of maintaining fluid, carbohydrate, and electrolyte levels during a shift.