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Orexins (hypocretins) are hypothalamic neuropeptides that innervate the entire neuraxis, including the prelimbic cortex and ventral tegmental area and have been implicated in ethanol-seeking behaviour. The present study aimed to use the orexin-1 (OX1 ) receptor antagonist SB-334867 to examine the role of prelimbic cortex and ventral tegmental area OX1 receptors in cue-induced reinstatement of ethanol-seeking. Ethanol-preferring rats (iP) rats were trained to self-administer ethanol (10 percent v/v, FR3) or sucrose (0.2-1 percent w/v, FR3) in the presence of reward-associated cues before being implanted with indwelling guide cannulae. Rats then underwent extinction training for 11 days. On test days, rats were given a microinjection of vehicle or SB-334867 (3 μg/side) and presented with reward-associated cues to precipitate reinstatement. Results show SB-334867 infused into the prelimbic cortex attenuated cue-induced reinstatement of ethanol-seeking, but not sucrose-seeking. OX1 antagonism in the ventral tegmental area also attenuated cue-induced reinstatement of ethanol-seeking. These findings suggest that OX1 receptors located in the prelimbic cortex and ventral tegmental area are part of a circuit driving cue-mediated ethanol-seeking behaviour.

Background: Although disulfiram has been used in the treatment of alcoholism due to the unpleasant sensations its concomitant ingestion with ethanol provokes, some patients reported stimulant effects after its ingestion. This issue has not been addressed in studies with animals. In mice, the stimulant effect of ethanol has been associated with increased locomotor activity and behavioural sensitization. This study sought to analyze the influence of disulfiram on the development of behavioural sensitization to the stimulant effect of ethanol. Methods: Male Swiss mice pre-treated with vehicle or disulfiram (15 mg/kg) received saline or ethanol (2.0 g/kg) every other day, for 5 days. Forty-eight hours afterwards mice were challenged with Saline, and 48 h later they received Disulfiram, or Disulfiram + Ethanol or Ethanol. Results: The co-administration of disulfiram (15 mg/kg) blocked the development of behavioural sensitization induced by ethanol (2.0 g/kg). Although the acute administration of disulfiram did not alter the locomotor activity, its acute administration-induced higher levels of locomotor activity in mice previously sensitized to ethanol than in controls which received saline. Conclusions: Our data suggest that besides the known psychological effects (fear of aversive effects) disulfiram efficacy on alcohol dependency treatment could also be due to its pharmacological interference in the brain neurotransmission.

This paper describes both theoretical and experimental studies on the application of a portable water mist extinguisher in suppressing multiple fire types. Two prototype portable water mist fire extinguishers were developed and their feasibility in extinguishing flammable liquid, cooking oil and wood crib fires, and for use in fires associated with an energized target was investigated. The interaction between water mist and the fire plume was studied by analyzing the instantaneous process of fire extinction, and fire and fuel temperature profiles. Both theoretical analysis and experimental results showed that the extinguishing mechanisms and process as well as water mist characteristics required (such as water flux density, droplet size and spray coverage) change with the types of fires encountered. The portable water mist extinguisher with appropriate mist characteristics was able to extinguish multiple fire types.

A study was undertaken to address concerns of corrosion in an electronic environment after fire suppression using HFC-227ea (C3F7H). Fire suppression using halocarbon agents, such as HFC-227ea, can produce thermal decomposition products, e.g., hydrogen fluoride (HF), which may cause corrosion in electronic equipment. In this study, full-scale experiments were conducted in a simulated electronic equipment room using six steel cabinets under various ventilation conditions. An in-cabinet cable fire was used in the tests as a fire source and HFC-227ea was used to suppress the fire. FTIR spectrometers were used to measure the gases in the cabinets and room. The test results showed that cabinet ventilation conditions affected fire extinguishment times in the cabinet, and therefore the amount of HF generation. In the open cabinet cable fire test, the concentration of HF was below 100 ppm in the fire cabinet. In the closed cabinet cable fire test, the maximum concentration of the HF reached 800 ppm in the fire cabinet. The migration of gaseous by-products from the fire cabinet to the adjacent non-fire cabinets was minimal. A large heptane pool fire test was also conducted in the simulated electronic equipment room; the maximum HF concentration in the room for this test reached 3900 ppm, slightly greater than the 3800 ppm within an open cabinet. However, peak HF concentrations of 1800 ppm and 500 ppm were observed within the ventilated and closed cabinets, respectively, during the heptane test.

Handheld FM-200, FE-36, CF3I and Halotron I extinguishers with 2B:C, 5B:C and 10B:C ratings (or equivalent) were tested for extinguishing Class B heptane pool fires in small and large enclosures (45, 120 and 21000 m3). Test results showed that the Halotron I and CF3I extinguishers performed better than the FE-36 and FM-200 extinguishers. The concentrations of the halocarbons and acid gas by-products in the operator breathing zone and surroundings were measured during the tests. Measurements showed that the agent concentrations were below the levels that would pose life or health risk to the operator. The concentrations of acid gas by-products generated during suppression, however, were at dangerous levels in the small enclosures (45 and 120 m3). Heat flux towards the operator was also measured. Heat exposure presented a severe hazard to the operator during the pool fire suppression. Test results indicate some potentially hazardous conditions to an unprotected operator.

This paper describes water mist fire suppression effectiveness under various ventilation conditions. The full-scale fire test series were conducted in an empty enclosure and in a simulated machiner...

We conducted a series of full-scale fire tests of a twin-fluid water mist system in an empty enclosure and in a simulated machinery space. During the tests, two water mist discharge modes, continuous and cycling, were used. We investigated the extinguishment performance of the water mist system using these two discharge modes under various fire scenarios, including different fire sizes, types, and locations, and different ventilation conditions. Test results showed that use of the cycling discharge substantially improved the effectiveness of the water mist system for fire suppression, in comparison to the continuous discharge. The corresponding extinguishing time and water requirement for fire suppression were significantly reduced, and some fires that could not be extinguished with the continuous discharge were extinguished with the cycling discharge. The improvement in fire suppression was attributed to high depletion and dilution rate of oxygen and the recurrent dynamic mixing generated by the cycling water mist discharge in the compartment.

Previous investigations made into protecting glazing assemblies with dedicated sprinklers included protecting wide windows with multiple sprinklers, but they did not address protecting exterior glazing assemblies from external fire exposure with sprinklers. In addition to a summary of the previous work on protecting glazing assemblies with dedicated sprinklers, this paper describes the test set-up and discusses the test results that led to a sprinkler system recommendation for protecting exterior glazing assemblies from external fire exposures.

Background According to the incentive sensitization theory, addiction is caused primarily by drug-induced sensitization in the brain mesocorticolimbic systems. After repeated ethanol administration, some animals develop psychomotor sensitization, a phenomenon which occurs simultaneously with the incentive sensitization. Recent evidence suggests the involvement of norepinephrine (NE) in drug addiction, with a critical role in the ethanol reinforcing properties. In this study we evaluated the influence of an agonist (phenylephrine) and an antagonist (prazosin) of alpha1-adrenergic receptors on the development and expression of behavioral sensitization to ethanol. Male Swiss mice, previously treated with ethanol or saline, were challenged with the combined administration of ethanol (or saline) with alpha1-adrenergic drugs. Prazosin (0.1; 0.5 and 1.0 mg/kg) and phenylephrine (1.0 and 2.0 mg/kg) administration blocked the expression of behavioral sensitization to ethanol. In another set of experiments, mice treated with 0.5 mg/kg of prazosin + ethanol did not present the development of behavioral sensitization. However, when challenged with ethanol alone, they showed the same sensitized levels of locomotor activity of those presented by mice previously treated with ethanol and saline. Phenylephrine (1.0 mg/kg) treatment did not affect the development of behavioral sensitization. Based on this data, we concluded that the alteration of alpha1-adrenergic receptors functioning, by the administration agonists or antagonists, affected the locomotor sensitization to the stimulant effect of ethanol, suggesting that the normal functioning of the noradrenergic system is essential to its development and expression.

Generally water is not favored for use in suppressing hot liquid fuel fires due to concerns of vapor explosion and boil-over, which could present potential danger to nearby personnel or firefighters. This paper reports on a series of full-scale fire experiments in which water mist was used in extinguishing large hot cooking oil fires. It was shown that water mist not only extinguished large fires effectively but also cooled hot oil from its ignition point (up to 360 °C) to below its flash point (200 °C) in a short period of time and prevented the fire from re-igniting. No vapor explosion was observed in the experiments when water droplets touched the hot oil whose temperature was higher than the superheat-limited temperature of water. A boiling layer of mixed bubbles, water droplets and oil was formed in the hot oil after all flames were extinguished, as water droplets boiled, bubbled and expanded in the hot oil. No boil-over or spillage of the oil over the container was observed in the experiments when water mist was discharged into the oil at high temperature (>300 °C) but boil-over did occur in experiments when the water mist was discharged into oil at a relatively moderate temperature (∼200 °C). In this paper, the mechanisms of cooling of hot oil by water mist are investigated, and the formation and development of the boiling layer during cooling are analyzed both experimentally and theoretically.

O conhecimento da microbiota que compõe as diferentes áreas do organismo tem importância reconhecida para a compreensão de doenças infecciosas que podem acometer os avestruzes, embora se disponha de dados limitados acerca deste assunto na literatura. Foi objetivo deste estudo determinar as espécies de microrganismos (bactérias aeróbias e fungos) que compõem a microbiota normal de avestruzes. Para tanto, foram coletadas amostras de cloaca (N=50) e orofaringe (N=50) de avestruzes hígidos de um criadouro. Das amostras de cloaca, foram isolados Escherichia coli (76% das amostras positivas), Bacillus spp. (60%), Streptococcus spp. (18%), Staphylococcus coagulase-negativo (16%), Pseudomonas aeruginosa (8%), Rhodotorula spp. (8%), dentre outros microrganismos isolados em cultura pura ou em associação com outras bactérias e/ou fungos. Das amostras de orofaringe, foram isolados E. coli (74% das amostras positivas), Candida albicans (44%), Bacillus spp. (38%), Staphylococcus coagulase-negativo (32%), Klebsiella pneumoniae (32%), Rhodotorula spp. (8%), Criptococcus spp. (4%), dentre outros microrganismos isolados em cultura pura ou em associação com outras bactérias e/ou fungos. Verificou-se predominância de bactérias Gram negativas em relação às Gram positivas, nas microbiotas da cloaca e orofaringe. Verificou-se freqüência de ocorrência semelhante entre bactérias Gram negativas nas microbiotas da cloaca e orofaringe, bem como de bactérias Gram positivas nestes mesmos sítios. Observou-se maior ocorrência de leveduras em amostras de orofaringe quando comparadas com as de cloaca. The knowledge of the microbiota present in different parts of the organism is important for the understanding of the infectious diseases of ostriches, although limited literature is available on this matter. The objective of this study was to determine the species of microorganisms (aerobic bacteria and fungi) that form the normal microbiota of ostriches. Samples from cloaca (N=50) and oropharynx (N=50) were collected from healthy ostriches of a breeder. In samples from cloaca, the following microorganisms were isolated: Escherichia coli (76% of the positive samples), Bacillus spp. (60%), Streptococcus spp. (18%), coagulase-negative Staphylococcus (16%), Pseudomonas aeruginosa (8%), Rhodotorula spp. (8%), among others, considering that these microorganisms were isolated in pure culture or associated with other bacteria and/or fungi. In samples collected from oropharynx, the following microorganisms were isolated: E. coli (74% of the positive samples), Candida albicans (44%), Bacillus spp. (38%), coagulase-negative Staphylococcus (32%), Klebsiella pneumoniae (32%), Rhodotorula spp. (8%), Criptococcus spp. (4%), among others, considering that these microorganisms were isolated in pure culture or associated with other bacteria and/or fungi. A predominance of Gram negative bacteria in relation to Gram positive ones was observed in the microbiotas of cloaca and oropharynx. A similar frequence of occurrence between Gram negative bacteria in the microbiotas of cloaca and oropharynx, as well as Gram positive bacteria in these same areas, was verified. A higher occurrence of yeasts was observed in samples of oropharynx when compared to samples from cloaca.

A series of full-scale experiments were conducted in a mock-up commercial cooking area to study extinguishing mechanisms and effectiveness of water mist against cooking oil fires. The impact of water mist characteristics, such as spray angle, droplet size, flow rate, discharge pressure and type of nozzle, on the effectiveness of water mist against cooking oil fires was investigated. A series of oil splash experiments were also conducted to determine if the oil was splashed by water mist. In addition, the change in oil composition during heating and fire suppression was determined using Fourier Transform Infrared (FTIR) technique. The study showed that cooking oil fires were very difficult to extinguish, because they burned at high temperature and re-ignited easily due to changes in oil composition during heating and fire suppression. The water mist systems developed in the present work effectively extinguished cooking oil fires and prevented them from re-ignition. The spray angle, discharge pressure, and water flow rate were important factors to determine the effectiveness of water mist in extinguishing cooking oil fires.

The progress on fire detection technologies has been substantial over the last decade due to advance in sensor, microelectronics and information technologies, as well as a greater understanding of fire physics. This paper provides a review of progress in fire detection technologies over the last decade, including various emerging sensor technologies (e.g., computer vision system, distributed fiber optic temperature sensor, and intelligent multiple sensor), signal processing and monitoring technology (e.g., real-time control via Internet) and integrated fire detection systems. Some problems and future research efforts related to current fire detection technologies are discussed.

The progress on the research and application of water mist technology in fire suppression has been substantial over the last decade. This paper, following our previous review on water mist fundamental studies, reviews recent water mist applications for the extinguishment of Class B spray and pool fires in machinery spaces, gas turbine enclosures, combat vehicles, and flammable liquid storage rooms; the extinguishment of Class A fires in residential occupancies, marine accommodations and public spaces,heritage buildings and libraries; the extinguishment of Class C fires in the electronic equipment and computer rooms; and for the protection of aircraft onboard cabin and cargo compartments. Some new applications, such as the use of water mist for the extinguishment of Class K fires in the commercial cooking areas; the use of water mist as a possible total-ship protection method, as well as the use of water mist for the protection of heavy goods vehicle shuttle trains, are also reviewed. Up-to-date development ofcorresponding test and design criteria for the installation of water mist fire protection systems and for the evaluation of the capabilities and limitations of water mist for fire suppression in some application areas, such as machinery spaces, ship's cabins and corridors, and turbine enclosures, are discussed.

Water spray is one method of protecting glazing exposed to fire. Research conducted at the National Research Council's National Fire Laboratory indicates that, under ideal con ditions, a window assembly, when protected by special sprinklers, will stay intact, and can obtain a fire resistance rating of 2 hours or longer. Experiments showed that there are several parameters related to sprinkler operation which affect the performance of the glazing assembly under fire exposure. This paper describes the test facility and discuss es the results of investigations conducted to determine the effect of the sprinkler activa tion time and sprinkler water flow rate on the effectiveness of dedicated sprinkler sys tems for protecting large glazing assemblies. The effect of the sprinklers on the average temperature and temperature gradient in the test room is also discussed.