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111.
In six experiments, we studied the effects of lesions to either the dorsal or ventral noradrenergic bundle on the acquisition and extinction of the conditioned emotional response (CER) as measured in a conditioned suppression paradigm. Infusions of the neurotoxin 6-hydroxy-dopamine (6-OHDA) into the trajectory of the dorsal noradrenergic ascending bundle (DNAB) impaired the acquisition of on-the-baseline and off-the-baseline conditioned suppression. The acquisition impairment for on-the-baseline conditioning was also shown to still be present when training did not commence until 8 weeks following central noradrenergic depletion. However, in rats previously trained on the CER, DNAB lesions did not affect performance. There was also a small resistance to extinction following on-, but not off-the-baseline conditioning. The acquisition impairment was shown not to be because of an altered sensitivity to the footshock. In contrast, infusions of 6-OHDA into the ventral noradrenergic ascending bundle (VNAB) had no effect upon the acquisition of the CER in an on-the-baseline procedure, but retarded its extinction to a much greater extent. The results here are discussed in terms of other acquisition deficits shown by rats with DNAB lesions and with reference to Gray's "anxiety" and Mason's "selective attention" theories of locus coeruleus function. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
112.
H Gao J Arrington EJ Beise B Bray RW Carr BW Filippone A Lung RD McKeown B Mueller ML Pitt CE Jones D DeSchepper G Dodson K Dow R Ent M Farkhondeh J Hansen W Korsch LH Kramer K Lee N Makins RG Milner DR Tieger TP Welch E Candell J Napolitano BB Wojtsekhowski C Tripp W Lorenzon 《Canadian Metallurgical Quarterly》1994,50(2):R546-R549
113.
Dominique Bouchard Jean-Paul Nadeau Daniel Simard François G. Hamel Belinda Howes Clotilde Paumelle 《Metallurgical and Materials Transactions B》2002,33(3):403-411
To determine the optimal roll temperature in a twin-roll copper-strip caster, copper blocks preheated between 25 °C and 350
°C were immersed in a bath of molten copper for 0.5 seconds. A significant increase in the contact heat-transfer coefficient
at the substrate-shell interface was obtained when the substrates were heated above 200 °C and the gain in the solidified
shell thickness was 20 pct. The shell growth was also approximately 35 pct more uniform at a high substrate temperature, and
micrographic examination showed the dendritic structure to be finer. The contact heat-transfer coefficient was decomposed
into two constituents, one for the substrate and the other for the shell. The former was found to be the limiting factor in
heat transfer. 相似文献
114.
115.
Ardeshir Mahdavi Belinda Kainrath Kristina Orehounig Josef Lechleitner 《Building Simulation》2008,1(3):223-233
This paper presents the results of a number of case studies concerning measurement and simulation of room acoustical parameters
in both historical and contemporary instances of bath spaces. Historical instances of such spaces are, in our study, traditional
hammam (bath) buildings in Mediterranean and north-African countries (Algeria, Morocco, Syria). Modern instances include a
modern hammam, a spa, and an indoor swimming pool in central Europe (Austria). The analysis is based on data obtained from
measurements and simulations of pertinent indicators of room acoustic quality in such spaces. The results of the analysis
permit the identification of certain salient features of room acoustics in highly humid spaces and corresponding technical
challenges (e.g., excessive reverberation and high noise exposure). Moreover, the results allow for the statistically grounded
estimation of uncertainties in simulation of room acoustics in architectural spaces. 相似文献
116.
Feng W Hatt BE McCarthy DT Fletcher TD Deletic A 《Environmental science & technology》2012,46(9):5100-5108
A large-scale stormwater biofilter column study was conducted to evaluate the impact of design configurations and operating conditions on metal removal for stormwater harvesting and protection of aquatic ecosystems. The following factors were tested over 8 months of operation: vegetation selection (plant species), filter media type, filter media depth, inflow volume (loading rate), and inflow pollutant concentrations. Operational time was also integrated to evaluate treatment performance over time. Vegetation and filter type were found to be significant factors for treatment of metals. A larger filter media depth resulted in increased outflow concentrations of iron, aluminum, chromium, zinc, and lead, likely due to leaching and mobilization of metals within the media. Treatment of all metals except aluminum and iron was generally satisfactory with respect to drinking water quality standards, while all metals met standards for irrigation. However, it was shown that biofilters could be optimized for removal of iron to meet the required drinking water standards. Biofilters were generally shown to be resilient to variations in operating conditions and demonstrated satisfactory removal of metals for stormwater-harvesting purposes. 相似文献
117.
Three procedures for the isolation of volatiles from grilled goat meat were compared: dynamic headspace entrainment on Tenax TA, simultaneous steam distillation-extraction, and solid-phase microextraction. Headspace entrainment on Tenax TA extracted the highest number of Maillard-derived volatile compounds. Two hundred and three volatile components were identified; 159 are reported for the first time in goat meat. Most of the volatiles detected (155) were lipid oxidation products, such as hydrocarbons, aldehydes, alcohols, ketones, carboxylic acids and esters. Forty-eight Maillard-derived compounds were identified, comprising pyrazines, pyrroles, thiophenes, furanthiol derivatives, alkyl and alicyclic sulphides, pyridines, and thiazoles. Some reported character impact compounds of cooked meat, e.g., 12-methyltridecanal, (E,E)-2,4-decadienal, methional, and dimethyl trisulphide were identified in the volatile profile of goat meat, together with a series of C2 to C5 alkylformylcyclopentenes, which have been reported in cooked chicken, pork, beef and lamb, as being important for the characteristic flavour impression of different animal species. 相似文献
118.
Diana M. Granda-Restrepo Herlinda Soto-Valdez Elizabeth Peralta Rosalba Troncoso-Rojas Belinda Vallejo-Crdoba Nohemí Gmez-Meza Abril Z. Graciano-Verdugo 《Food research international (Ottawa, Ont.)》2009,42(10):1396-1402
Antioxidant active packaging is a promising technology for whole milk powder (WMP) protection. In this study, the migration of α-tocopherol from a multilayer active packaging (made of high density polyethylene, ethylene vinyl alcohol and a layer of low density polyethylene containing the antioxidant) to WMP was studied. A model based on the Fick’s diffusion equation was used to calculate the diffusion coefficients (D) of α-tocopherol as 2.34 × 10−11, 3.06 × 10−11, and 3.14 × 10−11 cm2 s−1 at 20, 30 and 40 °C, respectively. The D at 20 °C was different from those at 30 and 40 °C (P < 0.05); but it was similar at 30 and 40 °C. This low influence of temperature on the migration of α-tocopherol from 20 to 40 °C assures the release at real storage and commercialization conditions in regions with warm/hot climate. The antioxidant delivering system delayed the lipid oxidation of WMP and it was more effective at 30 and 40 °C since the rate of oxidative reactions was higher at these temperatures than at 20 °C. 相似文献
119.
Aline Reyes‐Díaz Aarón F González‐Córdova Adrián Hernández‐Mendoza Ricardo Reyes‐Díaz Belinda Vallejo‐Cordoba 《International Journal of Dairy Technology》2018,71(1):1-9
Milk protein‐derived peptides have shown immunomodulatory properties either singly or in a mixture. However, information on the behaviour of these compounds is scarce, complicating their further study. This review presents current knowledge on immunomodulatory milk protein‐derived peptides, including hydrolysates, peptide fractions and single peptides. The evidence shows that hydrolysates derived from both casein and whey proteins show immunomodulatory effects; however, this bioactivity is mainly attributed to peptides derived from caseins. The identification of peptides in hydrolysates, as well as their characterisation and knowledge of the mechanisms behind their bioactivity, is necessary to further exploit their potential health benefits. 相似文献
120.
Felmingham Kim; Williams Leanne M.; Kemp Andrew H.; Liddell Belinda; Falconer Erin; Peduto Anthony; Bryant Richard 《Canadian Metallurgical Quarterly》2010,119(1):241
Although women have a greater propensity than men to develop posttraumatic stress disorder (PTSD) following trauma, sex differences in neural activations to threat have received little investigation. This study tested the prediction that trauma would heighten activity in automatic fear-processing networks to a greater extent in women than in men. Functional magnetic resonance imaging (fMRI) data were recorded in 23 participants with PTSD (13 women, 10 men), 21 trauma-exposed controls (9 women, 12 men), and 42 non-trauma-exposed controls (22 women, 20 men) while they viewed masked facial expressions of fear. Exposure to trauma was associated with enhanced brainstem activity to fear in women, regardless of the presence of PTSD, but in men, it was associated only with the development of PTSD. Men with PTSD displayed greater hippocampal activity to fear than did women. Both men and women with PTSD showed enhanced amygdala activity to fear relative to controls. The authors conclude that greater brainstem activation to threat stimuli may contribute to the greater prevalence of PTSD in women, and greater hippocampal activation in men may subserve an enhanced capacity for contextualizing fear-related stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献