Effect of habituation on the susceptibility of the rat to restraint ulcers

The frequency and gravity of restraint ulcers were found to significantly diminish in rats previously exposed to brief periods of immobilization. The rats' becoming habituated to restraint conditions probably explains this phenomenon

Couplage ou découplage ? Une analyse de la corrélation des cycles entre pays.

Un fort ralentissement de la croissance américaine affecterait la zone euro car la croissance économique de cette dernière reste assez largement corrélée avec celle des États-Unis.Synchronisation des cycles internationaux, modèles à facteurs.

O/Fe in metal-poor main sequence and subgiant stars

A study of the O/Fe ratio in metal-poor main sequence and subgiant stars is presented using the \ion{O{i}},6300 Å line, the \ion{O}{i} 7774 Å triplet, and a selection of weak \ion{Fe}{ii} lines observed on high-resolution spectra acquired with the VLT UVES spectrograph. The \ion{O{i} line is detected in the spectra of 18 stars with -2.4 < [Fe/H] < -0.5, and the triplet is observed for 15 stars with Fe/H ranging from -1.0 to -2.7. The abundance analysis was made first using standard model atmospheres taking into account non-LTE effects on the triplet: the \ion{O{i}} line and the triplet give consistent results with [O/Fe] increasing quasi-linearly with decreasing [Fe/H] reaching [O/Fe] =~ +0.7 at [Fe/H] = -2.5. This trend is in reasonable agreement with other results for [O/Fe] in metal-poor dwarfs obtained using standard atmospheres and both ultraviolet and infrared OH lines. There is also broad agreement with published results for [O/Fe] for giants obtained using standard model atmospheres and the \ion{O{i}} line, and the OH infrared lines, but the \ion{O}{i} lines give higher [O/Fe] values which may, however, fall into place when non-LTE effects are considered. When hydrodynamical model atmospheres representing stellar granulation in dwarf and subgiant stars replace standard models, the [O/Fe] from the \ion{O{i}} and \ion{Fe}{ii} lines is decreased by an amount which increases with decreasing [Fe/H]. These 3D effects on [O/Fe] is compounded by the opposite behaviour of the \ion{O{i}} (continuous opacity effect) and \ion{Fe}{ii} lines (excitation effect). The [O/Fe] vs. [Fe/H] relation remains quasi-linear extending to [O/Fe] =~ +0.5 at [Fe/H] = -2.5, but with a tendency of a plateau with [O/Fe] =~ +0.3 for -2.0 < [Fe/H] < -1.0, and a hint of cosmic scatter in [O/Fe] at [Fe/H] =~ -1.0. Use of the hydrodynamical models disturbs the broad agreement between the oxygen abundances from the \ion{O{i}} , \ion{O}{i}, and OH lines, but 3D non-LTE effects may serve to erase these differences. The [O/Fe] values from the \ion{O{i}} line and the hydrodynamical model atmospheres for dwarfs and subgiant stars are lower than the values for giants using standard model atmospheres and the \ion{O{i}}, and \ion{O}{i} lines. Based on observations collected at the European Southern Observatory, Chile (ESO Nos. 65.L-0131, 65.L-0507, and 67.D-0439)

Noncrossover Dither Creeping Mutation-Based Genetic Algorithm for Pipe Network Optimization

Ceylon [Sri Lanka]ColorVolume 9, Page 1

Detection and location of a partial blockage in a pipeline using damping of fluid transients

The effects of a partial blockage on pipeline transients are investigated analytically. A partial blockage is simulated using an orifice equation, and the influence of the blockage on the unsteady pipe flow is considered in the governing equations using a Dirac delta function. A simplified, linear dimensionless governing equation has been derived, and an analytical solution expressed in terms of a Fourier series has been developed under nonvarying boundary conditions. The linear analysis indicates that pipe friction and a partial blockage both introduce damping on fluid transients. The friction damping and blockage damping are exponential for each of the individual harmonic components. For each individual harmonic component, the blockage-induced damping depends on the blockage magnitude and position and is also independent of measurement location and the transient event. A new blockage detection method using the blockage-induced transient damping is developed based on the analytical solution. The magnitude of the blockage-induced damping rate indicates the size of the blockage, and the ratios of different damping rates can be used to locate the blockage. The proposed blockage detection method has been successfully used in detecting, locating, and quantifying a pipe blockage based on laboratory experiments. [Abstract from author

The importance of self-consistency in determining interface properties of S-I-N and D-I-N structures

We develop a method to solve the Bogoliubov de Gennes equation for superconductors self-consistently, using the recursion method. The method allows the pairing interaction to be either local or non-local corresponding to $s$ and $d$--wave superconductivity, respectively. Using this method we examine the properties of various $S-I-N$ and $D-I-N$ interfaces. In particular we self-consistently calculate the spatially varying density of states and the superconducting order parameter. We see that changing the strength of the insulating barrier, at the interface, does not, in the case of an $s$--wave superconductor, dramatically, change the low energy local density of states, in the superconducting region near the interface. This is in stark contrast to what we see in the case of a $D-I-N$ interface where the local particle density of states is changed dramatically. Hence we deduce that in calculating such properties as the conductance of $S-I-N$ and $D-I-N$ structures it is far more important to carry out a self-consistent calculations in the $d$--wave case.Comment: 14 pages, 8 figures, submitted to special issue of "Superlattices and Microstructures

Prediction of the Total Energy Cost of an Acute Bout of Resistance Exercise in Young Men and Women

Prediction of the Total Energy Cost of an Acute Bout of Resistance Exercise in Young Men and Women Brad S. Lambert†, Steven E. Martin‡, John S. Green‡ (FACSM), Aaron F. Carbuhn†, Stephen F. Crouse‡ (FACSM). Department of Health and Kinesiology, Texas A&M University, College Station, TX (Sponsor S.F. Crouse) ACSM currently recommends resistance training (RT) for each major muscle group at least 2 times per week with a traditional repetition range of 8-12 per set. Because many investigators as well as fitness professionals consider kcal expenditure when creating training protocols, energy costs during both RT and aerobic training must be considered. PURPOSE: To develop a regression equation to predict kcal expenditure for a RT bout involving each major muscle group using VO2max, height, weight, lean body mass, fat mass, and total exercise volume (TV=sets*reps*wt) as independent variables. METHODS: Twelve subjects (7 men, 5 women, age 21-25 yrs) were tested using the standard Bruce treadmill protocol for VO2max, and strength tested to determine their 3-5 repetition max (RM) on Keiser® RT equipment 1 week prior to their experimental RT bout. Body composition was assessed using DEXA. For their experimental RT bout, a warm-up set followed by 2-3 sets of 8-12 reps at 60-70% predicted 1RM were performed for each exercise. Each set was started every two minutes. Exercises progressed in the following order: leg press, chest press, leg curl, lat pull, leg ext., triceps ext., biceps curl. Oxygen consumption was measured continuously throughout the RT bout using an automated metabolic cart. Multiple Linear Regression was used to determine the best model for prediction of kcal consumption. Results: Mean kcal expenditure for the entire RT bout was 221.8±20.65 kcal (men = 272±36 & women = 150±16) with a mean kcal cost of 26.32-38.94 per exercise. Large muscle group/multi-joint exercises had the highest total kcal expenditures as expected. Collinearity diagnostics from the regression revealed that VO2max (L/min) and the square root of TV (TV0.5) were the only predictors needed in the model with all other variables being highly intercorrellated with VO2max (L/min), thus not adding significant improvement to the model. The prediction equation was (p\u3c0.05, R2=0.86): Total kcal = (37.264*VO2max L/min) + (1.087*TV0.5) – 132.488 CONCLUSIONS: VO2max (L/min) and TV0.5 were found to be significant predictors of the energy cost of a RT bout involving each major muscle group. In regards to fitness, performance, and weight management, this equation may aid practitioners and young exercising adults in documenting kcal expenditure from resistance training

Absence of charge backscattering in the nonequilibrium current of normal-superconductor structures

We study the nonequilibrium transport properties of a normal-superconductor-normal structure, focussing on the effect of adding an impurity in the superconducting region. Current conservation requires the superfluid velocity to be nonzero, causing a distortion of the quasiparticle dispersion relation within the superconductor. For weakly reflecting interfaces we find a regime of intermediate voltages in which Andreev transmission is the only permitted mechanism for quasiparticles to enter the superconductor. Impurities in the superconductor can only cause Andreev reflection of these quasiparticles and thus cannot degrade the current. At higher voltages, a state of gapless superconductivity develops which is sensitive to the presence of impurities.Comment: Latex file, 11 pages, 2 figures available upon request [email protected], to be published in Journal of Physics: Condensed Matte

Association of Aerobic Fitness and Metabolic Syndrome in Male Firefighters

Metabolic syndrome has been shown in numerous studies to be related to a higher incidence of coronary artery disease. A study by Jurca and coworkers (Med. Sci. Sports Exerc 36(8):1301-1307, 2004) found a relationship between aerobic fitness and the prevalence of metabolic syndrome in a group of men enrolled in the Aerobics Center Longitudinal Study (ACLS). In addition, recent work in our lab (Int J Exerc Sci 2(1): S43, 2009) has supported these findings. However, research exploring this relationship is still lacking in male firefighters, whose leading cause of line-of-duty deaths is heart attacks. Purpose: To further evaluate the association of metabolic syndrome and aerobic fitness in male fire fighters. Methods: As part of an annual physical exam, 210 male fire fighters (average age = 36) underwent evaluation of risk factors associated with metabolic syndrome as defined by NCEP III. These include the presence of three or more of the following: Waist Circumference \u3e 40 , HDL Cholesterol \u3c 40 mg/dL, Triglycerides \u3e 150 mg/dL, Blood Glucose \u3e 110 mg/dL, and Resting Blood Pressure \u3e 130/85 mm Hg. Aerobic Fitness was determined by estimating VO2max from time on treadmill during a Bruce protocol. Results: The subjects were ranked and divided into quartiles based on VO2max. All data were analyzed using a Chi Square test (p \u3c 0.05). Prevalence of metabolic syndrome increased significantly across quartiles as aerobic fitness declined. Conclusion: These data suggest that as aerobic fitness improves, the likelihood of male firefighters having metabolic syndrome decreases