The purpose of this study was to examine the thermoregulatory responses between self-paced and fixed-intensity exercise matched for average workload, in different thermal profiles matched for vapour ...pressure.
Thirteen moderate to highly trained cyclists maximal oxygen uptake: 59 (2.5)ml/kg/min; peak power output: 392.7 (14.1)W were recruited, where they underwent two 30min self-selected pace trials and two 30min fixed-intensity trials in 35̊C 34.9 (0.2)̊C; relative humidity: 50.1 (1.1)%; absolute humidity: 2.80 (0.1)kPa and 29̊C 29.2 (0.2)̊C; 69.4 (0.9)%; 2.81 (0.05)kPa with the same vapour pressure. The exercise intensity of the fixed-intensity trial was based on the average power output of the self-paced trial.
Despite cutaneous blood flow at the forearm region showing counter intuitive results 35̊C: self-paced vs. fixed-intensity, 279.1 (28.4) vs. 227.1 (19.1)AU, P=.042; 29̊C: 301.3 (25.8) vs. 378 (39.1)AU, P=.03, all others variables were not different between self-paced and fixed-intensity or different thermal profiles, such as rectal temperature 35̊C: self-paced vs. fixed-intensity, 38.0 (0.1) vs. 37.9 (0.1)̊C; 29̊C: 37.9 (0.1) vs. 38.0 (0.1)̊C, all P>.2, skin temperature 35̊C: self-paced vs. fixed-intensity, 36.3 (0.1) vs. 36.2 (0.1)̊C; 29̊C: 34.5 (0.2) vs. 34.4 (0.2)̊C, all P>.4.
We conclude that self-paced exercise does not reduce thermoregulatory strain in mild and moderate heat, when average workload is matched.
L’objectif de cette étude était d’examiner les réponses thermorégulatrices à deux types d’exercices, l’un à intensité librement choisie et l’autre à intensité fixe. Ces deux types d’exercice étaient appariés pour la charge de travail moyenne, et réalisés sous deux ambiances climatiques à pression partielle constante.
Treize cyclistes, modérément à hautement entraînés consommation maximale d’oxygène: 59 (2,5)ml/kg/min ; puissance de sortie maximale: 392,7 (14,1)W ont participé volontairement à cette étude. Ils ont réalisé deux exercices d’intensité librement choisie de 30min et deux exercices d’intensité fixe de 30min. Ces exercices ont été effectués sous deux ambiances climatiques différentes à 35̊C 34,9 (0,2)̊C ; humidité relative : 50,1 (1,1)%; humidité absolue : 2,80 (0,1)kPa et 29̊C 29,2 (0,2)̊C; 69,4 (0,9)%; 2,81 (0,05)kPa, à pression partielle constante. L’intensité de l’exercice à intensité fixe et prédéterminée était égale à la puissance moyenne de l’exercice à intensité librement choisie.
La grande majorité des variables représentatives de la thermorégulation n’étaient pas différente entre l’intensité librement choisie et l’intensité fixe. C’est le cas pour la température rectale À 35̊C, intensité libre vs. intensité fixe, 38,0 (0,1) vs. 37,9 (0,1)̊C; À 29̊C : 37,9 (0,1) vs. 38,0 (0,1)̊C, p>0,2, la température cutanée moyenne À 35̊C : intensité libre vs. intensité fixe, 36,3 (0,1) vs. 36,2 (0,1)̊C; À 29̊C : 34,5 (0,2) contre 34,4 (0,2)̊C, p>0,4. Seul le débit sanguin cutané mesuré au niveau de l’avant-bras était plus important à l’intensité libre qu’à intensité fixe à 35̊C (279,1 (28,4) vs. 227,1 (19,1)AU, p=0,042). L’inverse est observé à 29̊C (301,3 (25,8) vs. 378(39,1) AU, p=0,03).
Nous concluons que pour des charges de travail similaires, l’exercice à intensité librement choisie n’affecte pas les réponses thermorégulatrices à des ambiances climatiques chaudes, légère et modérée.
To promote the adhesion strength between diamond-like carbon (DLC) films and nitrile butadiene rubber (NBR) substrates, titanium-doped carbon (Ti-C) films prepared by dual-target magnetron sputtering ...under varied substrate bias voltages were used as an interlayer on the rough NBR. The surface topography and structure of Ti-C films were investigated by atomic force microscopy (AFM) and Raman spectra. Raman analysis indicates that the increase of substrate bias voltage leads to an increase of the number or the size of sp2 clusters in the Ti-C interlayer. The adhesion strength and tribological properties of DLC films coated on NBR substrate were scrutinized by a scratch tester and a ball-on-disk tribometer, respectively. It was found that DLC film with a Ti-C interlayer at a certain bias voltage exhibited superior wear resistance with a low coefficient of friction (CoF) during the sliding of 6000 laps. No clear damages in the coatings were observed from the wear tracks. Besides, the scratch test also revealed a reliable adhesion when the interlayer was prepared at −150 V, as confirmed by a scratch crack width of ~50 μm as compared to that of the pure DLC film increasing to ~ 120 μm. Therefore, a Ti-C interlayer could significantly enhance the adhesion and wear resistance of DLC thin films deposited on NBR.
Display omitted
•A Ti-C interlayer on rubber promotes the adhesion of diamond-like carbon film.•The tribology property of diamond-like carbon film is tailored by the Ti-C interlayer.•The wear resistance of diamond-like carbon film on rubber is tuned by bias voltage.
In this paper, the sulfate resistance of mortars made from ordinary Portland cement containing available pozzolans viz., fly ash and ground rice husk ash (RHA) was studied. Class F lignite fly ash ...and RHA were used at replacement dosages of 20 and 40% by weight of cement. Expansion of mortar prisms immersed in 5% sodium sulfate solution and the change in the pH values of the solution were monitored. The incorporation of fly ash and RHA reduced the expansion of the mortar bars and the pH values of the solutions. RHA was found to be more effective than fly ash. Examination of the fractured surface of mortar prisms, after a period of immersion, by scanning electron microscopy confirmed that sulfate attack of blended cement mortars was restricted owing to the reductions in calcium hydroxide and C/S ratio of the C–S–H gel in the blended cement mortar. In comparison to Portland cement mortar, less calcium sulfate and much less ettringite formations were found in the mortars made from blended cement containing RHA. The amounts of calcium sulfate and ettringite found in the blended cement mortar containing fly ash were also small but were slightly more than those of RHA mortar. Up to 40% of Portland cement could be replaced with these pozzolans in making blended cement with good sulfate resistance.
Genetic analysis of historical museum collections presents an opportunity to clarify the evolutionary history of understudied primate groups, improve taxonomic inferences, and inform conservation ...efforts. Among the most understudied primate groups, slow and pygmy lorises (genera
and
) are nocturnal strepsirrhines found in South and Southeast Asia. Previous molecular studies have supported five species, but studies using morphological data suggest the existence of at least nine species. We sequenced four mitochondrial loci,
, and
, for a total of 3324 aligned characters per sample from 41 historical museum specimens for the most comprehensive geographic coverage to date for these genera. We then combined these sequences with a larger dataset composed of samples collected in Vietnam as well as previously published sequences (total sample size N = 62). We inferred phylogenetic relationships using Bayesian inference and maximum likelihood methods based on data from each locus and on concatenated sequences. We also inferred divergence dates for the most recent common ancestors of major lineages using a BEAST analysis. Consistent with previous studies, we found support for
as a basal taxon to the others in the group. We also confirmed the separation between lineages of
from northern Vietnam/Laos/China and southern Vietnam/Cambodia and included a taxonomic revision recognizing a second taxon of pygmy loris,
. Our results found support for multiple reciprocally monophyletic taxa within Borneo and possibly Java. The study will help inform conservation management of these trade-targeted animals as part of a genetic reference database for determining the taxonomic unit and provenance of slow and pygmy lorises confiscated from illegal wildlife trade activities.
Motivated by the recent proposed models of the information engine Proc. Natl. Acad. Sci. USA 109, 11641 (2012) and the information refrigerator Phys. Rev. Lett. 111, 030602 (2013), we propose a ...minimal model of the information pump and the information eraser based on enzyme kinetics. This device can either pump molecules against the chemical potential gradient by consuming the information to be encoded in the bit stream or (partially) erase the information initially encoded in the bit stream by consuming the Gibbs free energy. The dynamics of this model is solved exactly, and the "phase diagram" of the operation regimes is determined. The efficiency and the power of the information machine is analyzed. The validity of the second law of thermodynamics within our model is clarified. Our model offers a simple paradigm for the investigating of the thermodynamics of information processing involving the chemical potential in small systems.
In this paper, the resistance to chloride penetration of concrete containing fly ash of various finenesses was examined. Three different fly ash finenesses viz., original fly ash, 45% fine portion ...and 10% fine portion fly ashes were used for the study. Chloride resistance of concretes was evaluated using the measurement of the Coulomb charge as per ASTM C1202 and by determination of chloride ingress after different periods of exposure to 3% NaCl solution in full immersion and partial immersion modes. From the tests, it is found that the resistance to chloride penetration of concrete depends on the fineness of fly ash. The rapid chloride permeability test (ASTM C1202) clearly indicates that the Coulomb charge of concrete at the age of 28 days is significantly reduced with the incorporation of fly ash. The decrease is promoted with an increase in fly ash fineness. The immersion of cut cylinders in the 3% NaCl solution for 3 and 6 months confirm that the resistance of the chloride penetration of concrete increases with an incorporation with fly ash and with an increase in the fly ash fineness.
Display omitted
•A cathodic serrated interface and voids are observed under current stressing.•The back-diffusion of Sn and Cu atoms are found in solder grooves.•The Sn orientation of the solder ...grooves influences the solder robustness.
In this paper, a Cu/SnAg3.0Cu0.5/Cu solder joint is current stressed under 6 A at 120 °C. After current stressing for 300 h, a serrated interface and voids are observed at the cathode. Current-crowding and thermal-crowding in solder grooves between adjacent Cu6Sn5 grains are found to be responsible for the back-diffusion of Sn and Cu atoms, eventually leading to the formation of a cathodic serrated interface and voids. In addition, the Sn orientation of the solder grooves may also play an important role in the robustness of the cathodic Cu6Sn5 grains and electrode. Our study may provide understanding of electromigration/thermomigration-induced evolution of the Cu/Sn interface under current stressing and provide visual data for interpreting early open-circuit failure of solder joints.
The objective of this field-scale study was to assess the effectiveness of applying an emulsified polycolloid substrate (EPS; containing cane molasses, soybean oil, and surfactants) biobarrier in the ...control and remediation of a petroleum-hydrocarbon plume in natural waters. An abandoned petrochemical manufacturing facility site was contaminated by benzene and other petroleum products due to a leakage from a storage tank. Because benzene is a petroleum hydrocarbon with a high migration ability, it was used as the target compound in the field-scale study. Batch partition and sorption experiment results indicated that the EPS to water partition coefficient for benzene was 232 mg/mg at 25 °C. This suggests that benzene had a higher sorption affinity to EPS, which decreased the benzene concentrations in groundwater. The EPS solution was pressure-injected into three remediation wells (RWs; 150 L EPS in 800 L groundwater). Groundwater samples were collected from an upgradient background well, two downgradient monitor wells (MWs), and the three RWs for analyses. EPS injection increased total organic carbon (TOC) concentrations (up to 786 mg/L) in groundwater, which also resulted in the formation of anaerobic conditions. An abrupt drop in benzene concentration (from 6.9 to below 0.04 mg/L) was observed after EPS supplementation in the RWs due to both sorption and biodegradation mechanisms. Results show that the EPS supplement increased total viable bacteria and enhanced bioremediation efficiency, which accounted for the observed decrease in benzene concentration. The first-order decay rate in RW1 increased from 0.003 to 0.023 d−1 after EPS application. Injection of EPS resulted in significant growth of indigenous bacteria, and 23 petroleum-hydrocarbon-degrading bacterial species were detected, which enhanced the in situ benzene biodegradation efficiency. Results demonstrate that the EPS biobarrier can effectively contain a petroleum-hydrocarbon plume and prevent its migration to downgradient areas, which reduces the immediate risk presented to downgradient receptors.
Petroleum hydrocarbons can be contained and biodegraded through the adsorption and enhanced bioremediation mechanisms after EPS injection. Display omitted
•Emulsified polycolloid substrate (EPS) barrier was developed for plume containment.•Benzene has high sorption affinity for EPS (EPS to H2O partition coefficient = 232).•EPS can prevent benzene and petroleum hydrocarbons migration to downgradient area.•Anaerobic petroleum hydrocarbons biodegradation can be enhanced within EPS barrier.•Sorption and biodegradation result in petroleum hydrocarbon removal within barrier.
Malaria affects ∼ ¼ billion people globally and requires the development of additional tools to aid in elimination efforts. The recently approved RTS,S/AS01 vaccine represents a positive step, ...however, the moderate efficacy necessitates the development of more efficacious vaccines. PfCSP is a key target antigen for pre-erythrocytic vaccines aimed at preventing Plasmodium falciparum malaria infections. Epitopes within the central repeat region and at the junction of the repeat and N-terminal domain are well documented as major protective B cell epitopes. On the other hand, a majority of antibodies against the epitopes in the C-terminal domain, have been shown to be non-protective against sporozoite challenge. The C-terminal domain, however, contains CD4+ and CD8+ T cell epitopes previously shown to be important for regulating immune responses. The present study was designed to further explore the immunomodulatory potential of the C-terminal domain using DNA vaccines encoding PfCSP with sequential C-terminal truncations following known T cell epitopes. Five DNA vaccines encoding different truncations of PfCSP within the C-terminal domain were administered via intramuscular route and in vivo electroporation for effective immunogenicity. Protection in mice was evaluated by challenge with transgenic P. berghei expressing PfCSP. In Balb/c mice, antibody responses and protective efficacy were both affected progressively with sequential deletion of C-terminal amino acid residues. Similar studies in C57Bl/6 mice revealed that immunizations with plasmids encoding truncated PfCSP showed partial protection from sporozoite challenge with no significant differences in antibody titers observed compared to full-length PfCSP DNA immunized mice. Further analysis revealed murine strain-specific differences in the recognition of specific epitopes.
PDF
