The effects of exercise and passive heating on the sweat glands ion reabsorption rates

The sweat glands maximum ion reabsorption rates were investigated (n = 12, 21.7 ± 3.0 years, 59.4 ± 9.8 kg, 166.9 ± 10.4 cm and 47.1 ± 7.5 mL/kg/min) during two separate endogenous protocols; cycling at 30% (LEX) and 60% VO2max(MEX) and one exogenous trial; passive heating (PH) (43°C water lower leg immersion) in 27°C, 50%RH. Oesophageal temperature (Tes), skin temperature (Tsk), and forearm, chest and lower back sweat rate (SR) and galvanic skin conductance (GSC) were measured. Salivary aldosterone was measured pre-and postheating (n = 3). Using the ∆SR threshold for an increasing ∆GSC to identify maximum sweat ion reabsorption rate revealed higher reabsorption rates during MEX compared to PH (mean of all regions: 0.63 ± 0.28 vs. 0.44 ± 0.3 mg/cm2/min, P  0.05). Aldosterone increased more during MEX (72.8 ± 36.6 pg/mL) compared to PH (39.2 ± 17.5 pg/mL) and LEX (1.8 ± 9.7 pg/mL). The back had a higher threshold than the forearm (P  0.05) (mean of all conditions; 0.64 ± 0.33, 0.42 ± 0.25, 0.54 ± 0.3 mg/cm2/min, respectively). Although the differences between conditions may be influenced by thermal or nonthermal mechanism, our results indicate a possibility that the sweat glands maximum ion reabsorption rates may be different between exercise and passive heating without mediating skin regional differences

The influence of local skin temperature on the sweat glands maximum ion reabsorption rate

PURPOSE: Changes in mean skin temperature (Tsk) have been shown to modify the maximum rate of sweat ion reabsorption. This study aims to extend this knowledge by investigating if modifications could also be caused by local Tsk. METHODS: The influence of local Tsk on the sweat gland maximum ion reabsorption rates was investigated in ten healthy volunteers (three female and seven male; 20.8 ± 1.2 years, 60.4 ± 7.7 kg, 169.4 ± 10.4 cm) during passive heating (water-perfused suit and lower leg water immersion). In two separate trials, in a randomized order, one forearm was always manipulated to 33 °C (Neutral), whilst the other was manipulated to either 30 °C (Cool) or 36 °C (Warm) using water-perfused patches. Oesophageal temperature (Tes), forearm Tsk, sweat rate (SR), galvanic skin conductance (GSC) and salivary aldosterone concentrations were measured. The sweat gland maximum ion reabsorption rates were identified using the ∆SR threshold for an increasing ∆GSC. RESULTS: Thermal [Tes and body temperature (Tb)] and non-thermal responses (aldosterone) were similar across all conditions (p > 0.05). A temperature-dependent response for the sweat gland maximum ion reabsorption rates was evident between 30 °C (0.18 ± 0.10 mg/cm2/min) and 36 °C (0.28 ± 0.14 mg/cm2/min, d = 0.88, p  0.05. CONCLUSION: The data indicate that small variations in local Tsk may not affect the sweat gland maximum ion reabsorption rates but when the local Tsk increases by > 6 °C, ion reabsorption rates also increase

Recombinant human activated protein C attenuates cardiovascular and microcirculatory dysfunction in acute lung injury and septic shock

Introduction: This prospective, randomized, controlled, experimental animal study looks at the effects of recombinant human activated protein C (rhAPC) on global hemodynamics and microcirculation in ovine acute lung injury (ALI) and septic shock, resulting from smoke inhalation injury

Microstructure and mechanical properties of mechanically alloyed ODS copper alloy for fusion material application

Advanced oxide dispersion strengthened copper alloys are promising structural materials for application in divertor system of future fusion reactors due to high irradiation resistance, high thermal conductivity, and good mechanical properties. In this study, a new ODS copper including 0.42wt%Y2O3 nanosized oxide particles wasdeveloped successfully by mechanical alloying method using addition of 1 wt% Stearic acid in Ar atmosphere.Mechanical alloying resulted in decrease of crystallite size to 28 nm in concurrent with increment of dislocation density and hardness to the saturated level of × −1.7 10 m15 2 and 226HV0.1 after 48 h milling, respectively.Consolidated ODS copper by SPS and then hot roll-annealing at 900 °C/60 min showed an average grain size of 1.1 μm with a near random texture. Furthermore, TEM observations demonstrated fine semicoherent Y2O3 oxide particles distributed with a misfit parameter (δ) of 0.17 in copper matrix with an average size of 10.8 nm andinterparticle spacing of 152 nm. Finally, tensile test evaluation determined comparable mechanical properties of the annealed ODS copper (Cu-0.42wt%Y2O3) with Glidcop-Al25 including a yield strength of 272 MPa and total elongation of 12%, by two mechanisms of grain boundary strengthening and oxide particle strengthening

Brass-texture induced grain structure evolution in room temperature rolled ODS copper

Currently, advanced ODS copper alloy is under study as a potential fusion material providing good mechanical properties. In this work, in order to develop a high performance ODS copper containing 0.5 wt% Y2O3 oxide particles, the effect of room temperature rolling and subsequent annealing on the grain structure evolution, texture development and tensile properties are studied using EBSD, TEM and tensile tests. Microstructure evolution studies show the grain structure coarsens by enhancing the Brass texture during increase of rolling reduction and a unique single crystal-like brass-texture deformed structure is achieved after 80% rolling reduction. We found the deformation mechanism of partial slip by a/6 ⟨211⟩ by dislocations facilitated by the pinning of a/2 ⟨101⟩ perfect dislocations through fine oxide particles is responsible for formation of Brass texture during room temperature rolling. Furthermore, the recrystallization of ODS copper retards to high temperature of ~700 °C and shows a fine-grained microstructure with different orientations of Goss, Brass, S and Copper. Evaluation of microstructure-mechanical properties of the recrystallized samples expresses that the bimodal grain size distribution at 800 °C for 30 min offers a good tensile strength-ductility (UTS: 491 MPa, elt: 19%) at ambient temperature

Microstructure development and high tensile properties of He/H2 milled oxide dispersion strengthened copper

This study describes the effect of microstructural development on high tensile properties of a newly developed He/H2 milled oxide dispersion strengthened copper in a large centimeter sized spherical morphology. Electron back scattered diffraction showed development of a strong texture of (110) plane in micron sized (1.2 μm) grains on the surface of milled spheres. A combination of microstructural features of inhomogeneous grain size, nanoscale lenticular/rectangular deformation twins, high dislocation density and fine oxide particles distribution induced a very high ultimate tensile strength (688 MPa)-ductility (8.6% elongation)

Microstructure development in cryogenically rolled oxide dispersion strengthened copper

Recently, advanced oxide dispersion strengthened (ODS) copper alloys have been developed using mechanical alloying process as a fusion material. In this study, to develop a superior ODS copper alloy containing 0.5wt% Y2O3, the effect of cryogenic rolling on microstructure development and tensile properties was studied using high resolution EBSD, TEM and tensile tests. During cryogenic deformation of ODS copper, grain structure remains in submicron size scale as a combinatorial result of geometrically effects, nanotwin bundle deformation, interaction of dislocations with fine oxide particles and some diffusional processes including static recovery and recrystallization. Clear microstructural characterizations confirmed nucleation of fine new oriented recrystallized grains mainly on the HABs of 80%cryogenic rolled ODS copper. Quantitative analyses indicated grain boundary migration at room temperature following cryogenic deformation originated from high driving force induced by grain boundary bulging and high mobility induced by vacancies. The tensile properties of cryogenic deformed samples showed superior tensile strength than room temperature deformation leading to UTS: 624 MPa, elt: 5.5%, while saturation of strength between 60%-80% reduction, approved occurrence of softening by diffusional processes

An unusual association of diffuse adenomyomatosis with dysplastic adenoma in chronic calculous cholecystitis: case presentation

<p>Abstract</p> <p>Background</p> <p>Gallbladder adenomyomatosis is an epithelial proliferation and hypertrophy of the muscularis mucosae of the gallbladder. Rokitansky-Aschoff sinuses are a characteristic of this condition. The segmental adenomyomatosis has a higher risk of developing into gallbladder carcinoma, especially in the fundal region of elderly patients.</p> <p>We report the case of a patient affected by chronic calculous cholecystitis with diffuse adenomyomatosis associated with dysplastic adenoma.</p> <p>Case presentation</p> <p>An 81-year-old woman presented at our hospital with a 1-year history of intermittent pain localized at the right upper abdominal quadrant, without diffusion to any other body part. On physical examination the abdomen was soft, not distended, and tender to palpation in the right upper quadrant. Murphy sign was negative. Laboratory tests were normal. The patient was scheduled for a laparoscopic cholecystectomy, and neither endoscopic ultrasonographic scan nor magnetic resonance imaging was performed. The operation, performed after obtaining informed consent, was uncomplicated and the intra-operative pathological examination showed no malignancy. The definitive pathological examination of the gallbladder showed: multiple stones of cholesterol origin; diffuse mucosal adenomyomatosis; and a 1.1 cm pedunculated mass localized at the fundus, whose surface was lumpy. This mass was diagnosed as an adenoma with multiple areas of severe dysplasia.</p> <p>Conclusions</p> <p>The adenoma of the gallbladder, together with the dysplasia, represents a biological carcinogenetic model. Carcinoma has rarely been reported in adenomyomatosis. Degenerative risk suggests surgery should be mandatory when there is a concomitant presence of large adenoma and adenomyomatosis.</p

An overview of research on biolubricants in Malaysia and Japan for tribological applications

Significant research and development is being done to substitute petroleum based lubricants with biolubricants derived from vegetable oils having similar physicochemical properties and tribological characteristics. This paper presents an overview of biolubricants in Malaysia and Japan for tribological applications. Research and development trends on biolubricants are described under the following categories: biolubricants as basestock, biolubricants in mixtures and biolubricants with additives. Excellent lubricant performance is obtained by biolubricant blends with selected additives. Biolubricants having similar performance to petroleum based lubricants, reduce dependence on nonrenewable resources, and increases markets industrial applications

Multimodel uncertainty changes in simulated river flows induced by human impact parameterizations

Human impacts increasingly affect the global hydrological cycle and indeed dominate hydrological changes in some regions. Hydrologists have sought to identify the human-impact-induced hydrological variations via parameterizing anthropogenic water uses in global hydrological models (GHMs). The consequently increased model complexity is likely to introduce additional uncertainty among GHMs. Here, using four GHMs, between-model uncertainties are quantified in terms of the ratio of signal to noise (SNR) for average river flow during 1971–2000 simulated in two experiments, with representation of human impacts (VARSOC) and without (NOSOC). It is the first quantitative investigation of between-model uncertainty resulted from the inclusion of human impact parameterizations. Results show that the between-model uncertainties in terms of SNRs in the VARSOC annual flow are larger (about 2% for global and varied magnitude for different basins) than those in the NOSOC, which are particularly significant in most areas of Asia and northern areas to the Mediterranean Sea. The SNR differences are mostly negative (-20% to 5%, indicating higher uncertainty) for basin-averaged annual flow. The VARSOC high flow shows slightly lower uncertainties than NOSOC simulations, with SNR differences mostly ranging from -20% to 20%. The uncertainty differences between the two experiments are significantly related to the fraction of irrigation areas of basins. The large additional uncertainties in VARSOC simulations introduced by the inclusion of parameterizations of human impacts raise the urgent need of GHMs development regarding a better understanding of human impacts. Differences in the parameterizations of irrigation, reservoir regulation and water withdrawals are discussed towards potential directions of improvements for future GHM development. We also discuss the advantages of statistical approaches to reduce the between-model uncertainties, and the importance of calibration of GHMs for not only better performances of historical simulations but also more robust and confidential future projections of hydrological changes under a changing environment