Journal articles: 'Long-term loss of strength'

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Clark, S. K. "Loss of Adhesion of Cord-Rubber Composites in Aircraft Tires." Tire Science and Technology 14, no. 1 (January 1, 1986): 33–43. http://dx.doi.org/10.2346/1.2148764.

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Abstract The degradation of adhesive strength between plies in aircraft tires was studied as a function of aging temperature, time, and environment. Adhesive strength degraded much faster than the cord tensile strength under the aging conditions used. Adhesive strength degraded faster in air than in nitrogen during the long-term aging. A 50% loss in adhesive strength is suggested as a reasonable critical value in determining tire life.

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Olama, Mohammed M., Kiran K. Jaladhi, Seddik M. Djouadi, and Charalambos D. Charalambous. "Recursive Estimation and Identification of Time-Varying Long-Term Fading Channels." Research Letters in Signal Processing 2007 (2007): 1–5. http://dx.doi.org/10.1155/2007/17206.

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This paper is concerned with modeling of time-varying wireless long-term fading channels, parameter estimation, and identification from received signal strength data. Wireless channels are represented by stochastic differential equations, whose parameters and state variables are estimated using the expectation maximization algorithm and Kalman filtering, respectively. The latter are carried out solely from received signal strength data. These algorithms estimate the channel path loss and identify the channel parameters recursively. Numerical results showing the viability of the proposed channel estimation and identification algorithms are presented.

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Aygörmez, Yurdakul, and Orhan Canpolat. "Long-term sulfuric and hydrochloric acid resistance of silica fume and colemanite waste reinforced metakaolin-based geopolymers." Revista de la construcción 20, no. 2 (August 2021): 291–307. http://dx.doi.org/10.7764/rdlc.20.2.291.

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For this paper, silica fume (SF), slag (S), and colemanite waste (C) were added to metakaolin (MK)-based geopolymer composites and exposed to 10% (by volume) hydrochloric acid (HCl) and sulfuric acid (H2SO4) solutions for up to 12 months. Geopolymer composites were examined in terms of weight loss, compressive strength, and flexural strength at 3, 6, and 12 months in solutions. Furthermore, Scanning Electron Microscopy (SEM), Micro-computed Tomography (micro-CT), Fourier Transform Infrared Spectroscopy (FTIR), and X-ray Diffraction (XRD) analyses were carried out to examine the microstructure before and after acid attacks. An important decrease in flexural and compressive strengths was seen when geopolymer mortars were subjected to sulfuric and hydrochloric acid attacks. The main cause of this situation is the deterioration of the oxy-aluminum bridge (-Al-Si-O) when exposed to sulfuric and hydrochloric acid. The oxy-aluminum bridge (-Al-Si-O), the primary factor in the geopolymer matrix, plays a significant role in consolidating the gel and enhancing the bond formed between the matrix components. Despite this, geopolymer mortar samples maintain the aluminosilicate structure. Compared to hydrochloric acid, sulfuric acid is a stronger solution, resulting in a greater loss of compressive and flexural strengths.

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Garthe, Ina, Truls Raastad, and Jorunn Sundgot-Borgen. "Long-Term Effect of Weight Loss on Body Composition and Performance in Elite Athletes." International Journal of Sport Nutrition and Exercise Metabolism 21, no. 5 (October 2011): 426–35. http://dx.doi.org/10.1123/ijsnem.21.5.426.

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Context:When weight loss (WL) is needed, it is recommended that athletes do it gradually by 0.5–1 kg/wk through moderate energy restriction. However, the effect of WL rate on long-term changes in body composition (BC) and performance has not been investigated in elite athletes.Purpose:To compare changes in body mass (BM), fat mass (FM), lean body mass (LBM), and performance 6 and 12 mo after 2 different WL interventions promoting loss of 0.7% vs. 1.4% of body weight per wk in elite athletes.Methods:Twenty-three athletes completed 6- and 12-mo postintervention testing (slow rate [SR] n = 14, 23.5 ± 3.3 yr, 72.2 ± 12.2 kg; fast rate [FR] n = 9, 21.4 ± 4.0 yr, 71.6 ± 12.0 kg). The athletes had individualized diet plans promoting the predetermined weekly WL during intervention, and 4 strength-training sessions per wk were included. BM, BC, and strength (1-repetition maximum) were tested at baseline, postintervention, and 6 and 12 mo after the intervention.Results:BM decreased by ~6% in both groups during the intervention but was not different from baseline values after 12 mo. FM decreased in SR and FR during the intervention by 31% ± 3% vs. 23% ± 4%, respectively, but was not different from baseline after 12 mo. LBM and upper body strength increased more in SR than in FR (2.0% ± 1.3% vs. 0.8% ± 1.1% and 12% ± 2% vs. 6% ± 2%) during the intervention, but after 12 mo there were no significant differences between groups in BC or performance.Conclusion:There were no significant differences between groups after 12 mo, suggesting that WL rate is not the most important factor in maintaining BC and performance after WL in elite athletes.

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Sahoo, Sanjukta, and Trupti Ranjan Mahapatra. "ANN Modeling to study strength loss of Fly Ash Concrete against Long term Sulphate Attack." Materials Today: Proceedings 5, no. 11 (2018): 24595–604. http://dx.doi.org/10.1016/j.matpr.2018.10.257.

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Ismail, Mohammad, Bala Muhammad, and Mohamed ElGelany Ismail. "Compressive strength loss and reinforcement degradations of reinforced concrete structure due to long-term exposure." Construction and Building Materials 24, no. 6 (June 2010): 898–902. http://dx.doi.org/10.1016/j.conbuildmat.2009.12.003.

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Niaza, Kirill V., Fedor S. Senatov, Andrey Stepashkin, Natalia Yu Anisimova, and Mikhail V. Kiselevsky. "Long-Term Creep and Impact Strength of Biocompatible 3D-Printed PLA-Based Scaffolds." Nano Hybrids and Composites 13 (January 2017): 15–20. http://dx.doi.org/10.4028/www.scientific.net/nhc.13.15.

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In the present work porous scaffolds for trabecular bone defects replacement were studied. PLA and PLA/HA сomposites were obtained by extrusion. Scaffolds were obtained by 3D-printing by fused filament fabrication method. Long-term creep and Charpy impact tests show that PLA/HA scaffolds with the maximum force for destruction at impact of 119 N can function under a load of up to 10 MPa without shape changing and loss of mechanical properties. In vivo tests were used to investigate biocompatibility of scaffolds. The scaffolds may be used as implants for unloaded small bone defects replacement

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Marchand, L., M. Derenne, and A. Bazergui. "Weight Loss Correlation for Sheet Gasket Materials." Journal of Pressure Vessel Technology 114, no. 1 (February 1, 1992): 1–7. http://dx.doi.org/10.1115/1.2929007.

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Elevated temperature aged tests were performed on two fiber-reinforced sheet gasket materials with acrylonitrile-butadiene rubber (NBR) binder; a compressed asbestos and a compressed aramid. Weight loss, relaxation and cross-fiber tensile strength measurements were taken. An aging parameter (Ap) based on weight loss correlation is proposed which successfully groups data for different test times and temperatures. Ap is shown to have good potential as an accurate predictive parameter for determining long-term operating temperature on the basis of short-term tests. The use of the thermogravimetric approach is also discussed.

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Porter, Michelle M. "The Effects of Strength Training on Sarcopenia." Canadian Journal of Applied Physiology 26, no. 1 (February 1, 2001): 123–41. http://dx.doi.org/10.1139/h01-009.

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In the past decade strength training has been investigated extensively as a means of reversing the muscle mass loss that occurs with aging (sarcopenia). High intensity resistance training (HIRT) has led to increased protein synthesis, along with muscle hypertrophy measured at the whole body, whole muscle, and muscle fibre levels, in older adults. Typically, the strength increments associated with HIRT have been much larger than the hypertrophic response. However, most HIRT periods have been quite short. Less is known about the long term hypertrophic response to HIRT in older adults. In order to lessen the effects of sarcopenia, HIRT should continue over the long-term in older adults, to improve functional performance and health. Key words: aging, muscle physiology, hypertrophy, exercise, weight lifting

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Liang, Robert Y., and Suckhong Lee. "Short-Term and Long-Term Aging Behavior of Rubber Modified Asphalt Paving Mixture." Transportation Research Record: Journal of the Transportation Research Board 1530, no. 1 (January 1996): 11–17. http://dx.doi.org/10.1177/0361198196153000102.

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Aging of asphalt has been an important subject area that has received extensive studies in recent years. Test results of short-term and long-term aging behavior of crumb rubber modifier (CRM) modified asphalt paving materials are presented. Eighteen combinations of CRM modified binders in terms of CRM size, CRM content, and base asphalt cement grade were studied by Brookfield viscometer test and dynamic shear rheometer test. The short-term aged binders were prepared using thin film oven test. Viscosity was measured at 350°F in the Brookfield thermosel after mixing at 375°F for 2 hr. The test results showed that the size and percentage of CRM affected the viscosity development in the modified binders: the smaller the CRM size and the higher the CRM content, the higher the viscosity measured after 2-hr reaction at 375°F. Short-term aging exerted more viscosity increase in the CRM modified binders than in the unmodified binders. Modified binders showed less weight loss than unmodified binders. The modified binders showed higher complex modulus G* than unmodified. Short-term aging increased G*, with modified binders exhibiting higher increase. The Marshall mix design yielded various CRM modified mixes. The result of indirect tensile strength tests showed that short-term and long-term aging increased the measured tensile strengths. The resilient modulus test results, in general, supported the general understanding that aging tended to increase resilient modulus.

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Huang, Jian Wei. "Long-Term Performance Prediction of GFRP Bar in Moist Concrete under Sustained Loads." Advanced Materials Research 255-260 (May 2011): 3119–23. http://dx.doi.org/10.4028/www.scientific.net/amr.255-260.3119.

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In this paper, the tensile strength retention of GFRP bars embedded in moist concrete under sustained loads is discussed on the basis of reported data. Long-term performance of GFRP bar is predicted by a newly developed model through time-temperature shift and time extrapolation approaches. Results indicated that higher temperature and longer exposure time result in more tensile strength loss of the sustained GFRP bar in moist concrete. Above certain temperature, GFRP bar in moist concrete with about 20% sustained load fails in rupture of GFRP bar for 75-year design lifetime. The temperature effect shall be taken into account in the design codes/guidelines.

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BURMAN, A., D. MAITY, S. SREEDEEP, and I. GOGOI. "LONG-TERM INFLUENCE OF CONCRETE DEGRADATION ON DAM–FOUNDATION INTERACTION." International Journal of Computational Methods 08, no. 03 (September 2011): 397–423. http://dx.doi.org/10.1142/s0219876211002472.

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The dam–foundation interaction behavior under the application of seismic load has been investigated in the present paper using finite element technique in the time domain. Since the dam face is in constant contact with water, concrete degradation due to hygromechanical loading is inevitable and should be considered in the analysis procedure. This ageing process of concrete leads to loss of stiffness and strength of the material. Therefore, to assess the behavior of the dam at a later stage of its life, it is important to determine the proper strength of the concrete at a certain age. An approach to include the time-dependent degradation of concrete owing to environmental factors and mechanical loading in terms of isotropic degradation index is presented. An iterative scheme has been developed to model the dam–foundation interaction effects of the coupled system. The strains and the displacements are observed to increase if the ageing procedure of the gravity dam is taken into account. The long-term behavior of the aged concrete gravity and foundation interaction has been observed by using a developed ageing model for concrete.

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Schenker, K., U. Kolb, and H. Ritter. "Nova Outbursts and the Secular Evolution of Cataclysmic Variables." International Astronomical Union Colloquium 158 (1996): 447–48. http://dx.doi.org/10.1017/s0252921100039373.

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AbstractWe present calculations of the long-term evolution of CVs which include the influence of nova outbursts. In particular we investigate the consequences of the discontinuous mass loss due to recurring outburst events and the effects of frictional angular momentum loss (FAML), i.e. the interaction of the expanding nova envelope with the secondary. We show that a description assuming continuous mass loss – averaged over a complete nova cycle – is applicable for determining the mean mass transfer rate and the secular evolution both with and without FAML. Between two subsequent outbursts, deviations from the mean evolution depend on the strength of FAML and on the mass ejected during the outburst. Formally FAML is a consequential angular momentum loss [1] and therefore increases the mean mass transfer rate by pushing the systems closer to mass transfer instability. Depending on the actual strenghth of FAML the long-term evolution of CVs could be significantly different from the standard model predictions.

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Spelter, Arne, Sarah Bergmann, Jan Bielak, and Josef Hegger. "Long-Term Durability of Carbon-Reinforced Concrete: An Overview and Experimental Investigations." Applied Sciences 9, no. 8 (April 21, 2019): 1651. http://dx.doi.org/10.3390/app9081651.

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Despite intensive research on material properties of non-metallic technical textiles for internal reinforcement in concrete, the long-term durability is not yet fully understood. In this work, results of preloaded long-term durability tensile tests on carbon-reinforced concrete specimens under environmental factors of stress, temperature, moisture and alkalinity are presented. Based on investigations of non-metallic glass fiber reinforcements with polymer matrices, where strength losses occur over time, it was planned to derive a time to failure curve and to determine a reduction factor for the tensile strength of the carbon textile reinforcement. However, no loss of strength was discovered in residual capacity tests due to the high material resistance and therefore no reduction factor due to the environmental factors could be derived. After more than 5000 h of testing, the residual capacity tests showed an increase in the ultimate failure stress in comparison with the short-term tests. In addition to the long term-durability tests, the influence of the preloading was investigated. The preload was applied to the long-term tests and led to a straighter alignment and loading of the filaments and thus to an increase in the ultimate capacity.

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Greenwood, K. L., D. A. MacLeod, and K. J. Hutchinson. "Long-term stocking rate effects on soil physical properties." Australian Journal of Experimental Agriculture 37, no. 4 (1997): 413. http://dx.doi.org/10.1071/ea96131.

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Summary. The effects of sheep stocking rate on soil physical properties were investigated in a long-term (>30-year-old) grazing trial on the Northern Tablelands of New South Wales. The soil physical properties studied were unsaturated hydraulic conductivity, soil strength and bulk density. Significant differences between the ungrazed and grazed pastures were found for all soil physical measurements. Compaction by sheep was limited to the upper 5 cm of the soil profile and resulted in lower porosity, mainly due to loss of pores larger than 1.2 mm equivalent diameter. However, after 30 years, the pastures grazed at 10, 15 and 20 sheep/ha had similar soil physical properties. Soil physical properties appear to be relatively insensitive to stocking rate in the long term and therefore other factors, such as maintenance of pasture cover, should be given a higher priority in grazing management decisions.

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Park, Ki-Bong, and Takafumi Noguchi. "Effects of Mixing and Curing Temperature on the Strength Development and Pore Structure of Fly Ash Blended Mass Concrete." Advances in Materials Science and Engineering 2017 (2017): 1–11. http://dx.doi.org/10.1155/2017/3452493.

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The aim of this work is to know clearly the effects of temperature in response to curing condition, hydration heat, and outside weather conditions on the strength development of high-performance concrete. The concrete walls were designed using three different sizes and three different types of concrete. The experiments were conducted under typical summer and winter weather conditions. Temperature histories at different locations in the walls were recorded and the strength developments of concrete at those locations were measured. The main factors investigated that influence the strength developments of the obtained samples were the bound water contents, the hydration products, and the pore structure. Testing results indicated that the elevated summer temperatures did not affect the early-age strength gain of concrete made using ordinary Portland cement. Strength development was significantly increased at early ages in concrete made using belite-rich Portland cement or with the addition of fly ash. The elevated temperatures resulted in a long-term strength loss in both belite-rich and fly ash containing concrete. The long-term strength loss was caused by a reduction in the degree of hydration and an increase in the total porosity and amount of smaller pores in the material.

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Shamsuddoha, Md, Götz Hüsken, Wolfram Schmidt, Hans-Carsten Kühne, and Matthias Baeßler. "Long-term mechanical and shrinkage properties of cementitious grouts for structural repair." RILEM Technical Letters 4 (May 24, 2019): 9–15. http://dx.doi.org/10.21809/rilemtechlett.2019.82.

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Grouts have numerous applications in construction industry such as joint sealing, structural repair, and connections in precast elements. They are particularly favoured in rehabilitation of structures due to penetrability and convenience of application. Grouts for repair applications typically require high-performance properties such as rapid strength development and superior shrinkage characteristics. Sometimes industrial by-products referred as supplementary cementitious materials (SCM) are used with neat cement due to their capabilities to provide binding properties at delayed stage. Micro silica, fly ash and metakaolin are such SCMs, those can modify and improve properties of cement products. This study aims at investigating long-term mass loss and linear shrinkage along with long-term compressive and flexural strength for grouts produced from ultrafine cement and SCMs. A series of mixtures were formulated to observe the effect of SCMs on these grout properties. Properties were determined after 365 days of curing at 23oC and 55% relative humidity. The effect of SCMs on the properties are characterised by statistical models. Response surfaces were constructed to quantify these properties in relation to SCMs replacement. The results suggested that shrinkage was reduced by metakaolin, while micro silica and fly ash had positive effects on compressive and flexural strength, respectively.

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Wu, Qiongyao, Liangliang Huo, Enchun Zhu, Shuang Niu, and Huajie Wang. "An Investigation of the Duration of Load of Structural Timber and the Clear Wood." Forests 12, no. 9 (August 25, 2021): 1148. http://dx.doi.org/10.3390/f12091148.

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In this study, DOL of structural timber and the clear wood and DOL of modulus of elasticity of wood were investigated. The dimension lumber of Spruce-Pine-Fir of Grade No. 2 and Grade No. 3 and the small clear specimens of the same species of the dimension lumber were used to conduct the short-term and the long-term bending test. The short-term strength distributions of the dimension lumber and the small clear specimens were obtained. The long-term tests were conducted under constant environmental conditions for 18 months. The sample matching technique was used to estimate the short-term strength of the specimens that underwent long-term tests. It was found out that there is virtually no difference in DOL between different grades or quality of lumber and no difference between structural timber and clear wood, and DOL obtained from the test of this study is more in agreement with Wood’s curve. A threshold stress ratio of about 0.55, loaded above which the wood began to experience strength loss, was revealed from the test. Making use of the threshold ratio concept, the DOL of wood can be obtained not only from failed specimens under load in the process of the long-term loading, but also from the ramp loading test of the specimens that survived the long-term test. Sustained load also poses DOL on the modulus of elasticity of wood, though to less degree than DOL of strength of wood.

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Davison, Matt, C. Essex, and J. S. Shiner. "Global Predictability of Chaotic Epidemiological Dynamics in Coupled Populations." Open Systems & Information Dynamics 10, no. 04 (December 2003): 311–20. http://dx.doi.org/10.1023/b:opsy.0000009553.55368.7e.

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When the dynamics of an epidemic are chaotic, detailed prediction is effectively impossible, except perhaps in the short term. However, a probability distribution underlying the motion does allow for the long term prediction of statistical measures such as the mean or the standard deviation. Even this weaker long term predictability might be lost if distinct populations with chaotic dynamics are coupled. We show that such coupling can result in a phenomenon we call “sensitive dependence on neglected dynamics”. In light of this phenomenon, it is somewhat surprising that when two logistic maps are coupled, the long term predictability of the mean and standard deviation is maintained. This is true even though the probability distribution describing the time series depends on the coupling strength. The coupling-strength dependence does reveal itself in the loss of predictability of higher order moments such as skewness and kurtosis.

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Karozou, Aspasia, Stavroula Konopisi, Eleni Pavlidou, and Maria Stefanidou. "Long-Term Behavior and Durability of Alkali-Activated Clay Mortars." Materials 13, no. 17 (August 27, 2020): 3790. http://dx.doi.org/10.3390/ma13173790.

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The need to increase the durability of clay-based materials, due to their inherent low strength and vulnerability in contact with water, led researchers to examine different options. In this paper, clay mortars were produced using four different activating solutions. Alkali hydroxides, alkali carbonates, and alkali silicates activating solutions were used. Interest is given to long term properties while their behavior to wetting–drying and freeze–thaw cycles is recorded. In total, the results of the experiments indicated the positive effect of the potassium metasilicate on mechanical characteristics presenting, however, low performance at wetting–drying. The combination of sodium metasilicate with sodium hydroxide solution has also presented a positive effect on both mechanical and physical properties. In contrast, sodium carbonate acted better in enhancing physical properties and granting water-resistant abilities. Moreover, the performance of the specimens mixed with water–glass addition presented excellent volume stability and low mass loss in durability tests.

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Lee, Sang Ll, Moon Hee Lee, Jin Kyung Lee, Dong Su Bae, and Joon Hyun Lee. "Corrosion Resistance and Mechanical Properties of Carbon Steel under a High Temperature Pressurized Water." Key Engineering Materials 345-346 (August 2007): 1027–30. http://dx.doi.org/10.4028/www.scientific.net/kem.345-346.1027.

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The long-term corrosion strength properties for the carbon steels under pressurized water atmosphere have been investigated, in the conjunction with the detailed analysis of their microstructures. The corrosion test for carbon steels was carried out at the temperature of 200°C under a water pressure of 10 MPa. The corrosion test samples were maintained up to 50 weeks in the tube shaped reactor. The mechanical strength and the microstucture of carbon steels suffered from the long term corrosion test were evaluated by SEM, XRD and tensile test. The weight loss of carbon steel by the corrosion test was also examined. The tensile strength of carbon steels decreased with the increase of corrosion time under a pressurized water atmosphere, accompanying the creation of severe corrosion damages like stress corrosion crack.

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Hagiwara, Naruki, Shoma Sekizaki, Yuji Kuwahara, Tetsuya Asai, and Megumi Akai-Kasaya. "Long- and Short-Term Conductance Control of Artificial Polymer Wire Synapses." Polymers 13, no. 2 (January 19, 2021): 312. http://dx.doi.org/10.3390/polym13020312.

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Networks in the human brain are extremely complex and sophisticated. The abstract model of the human brain has been used in software development, specifically in artificial intelligence. Despite the remarkable outcomes achieved using artificial intelligence, the approach consumes a huge amount of computational resources. A possible solution to this issue is the development of processing circuits that physically resemble an artificial brain, which can offer low-energy loss and high-speed processing. This study demonstrated the synaptic functions of conductive polymer wires linking arbitrary electrodes in solution. By controlling the conductance of the wires, synaptic functions such as long-term potentiation and short-term plasticity were achieved, which are similar to the manner in which a synapse changes the strength of its connections. This novel organic artificial synapse can be used to construct information-processing circuits by wiring from scratch and learning efficiently in response to external stimuli.

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Liang, Ji Feng, Chao Zhang, and Xin Yu Fang Wang. "Experimental Study of Sulfate Attack Resistance Performance on Cement Concrete Pavement." Applied Mechanics and Materials 505-506 (January 2014): 270–73. http://dx.doi.org/10.4028/www.scientific.net/amm.505-506.270.

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Airport concrete pavement in high latitude northwest area attacked by sulfate of different extent, which influence early strength and ultimate strength of cement concrete. In this paper, the double doped silica fume and fly ash concrete have been made long-term immersion test research. From the mass loss rate, compressive strength and flexural strength, effect on the corrosion resistance are studied with fly ash, silicon ash adding in a composite Portland cement. Methods to improve the performance of sulfate attack resistance are obtained by experiment.

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Sagarra-Romero, Lucía, and Andrea Viñas-Barros. "COVID-19: Short and Long-Term Effects of Hospitalization on Muscular Weakness in the Elderly." International Journal of Environmental Research and Public Health 17, no. 23 (November 24, 2020): 8715. http://dx.doi.org/10.3390/ijerph17238715.

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The COVID-19 pandemic has recently been the cause of a global public health emergency. Frequently, elderly patients experience a marked loss of muscle mass and strength during hospitalization, resulting in a significant functional decline. This paper describes the impact of prolonged immobilization and current pharmacological treatments on muscular metabolism. In addition, the scientific evidence for an early strength intervention, neuromuscular electrical stimulation or the application of heat therapy during hospitalization to help prevent COVID-19 functional sequels is analyzed. This review remarks the need to: (1) determine which potential pharmacological interventions have a negative impact on muscle quality and quantity; (2) define a feasible and reliable pharmacological protocol to achieve a balance between desired and undesired medication effects in the treatment of this novel disease; (3) implement practical strategies to reduce muscle weakness during bed rest hospitalization and (4) develop a specific, early and safe protocol-based care of functional interventions for older adults affected by COVID-19 during and after hospitalization.

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Rathje, H., T. E. Schellin, and A. Brehm. "Speed loss in waves and wave-induced torsion of a wide-breadth containership." Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment 225, no. 4 (August 25, 2011): 387–401. http://dx.doi.org/10.1177/1475090211412681.

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Aspects relevant for operational and structural design of a wide-breadth, neo-panmax containership were addressed. First, speed loss in waves was investigated. Second, wave-induced global hull girder torsion was determined to assess the effects of the increased breadth on this load component, generally considered critical for the ship’s structural strength. An extended Reynolds-averaged Navier–Stokes (RANS) equations solver simulated the ship advancing in calm water as well as in selected regular head and bow waves. A boundary element method (BEM) computed transfer functions of wave-induced ship response. Before using spectral techniques to obtain long-term predictions of hull girder torsion, these transfer functions were corrected to account for non-linear effects. To assess the reliability of the computed long-term hull girder torsion, the extended RANS equations solver was used to perform additional simulations for this ship advancing at selected speeds in equivalent regular design waves that represent wave conditions considered critical for structural design. Except for the very forward part of the ship, long-term BEM-based predictions of wave-induced hull girder torsion did not exceed rule values. Comparative BEM and RANS predictions of hull girder torsion differed significantly, underlining the need to validate the predictions systematically.

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Kulesh, A. Yu, M. A. Eron’yan, and I. K. Meshkovskii. "Short-term loss of strength of as-drawn silica optical fibers." Technical Physics Letters 40, no. 3 (March 2014): 260–62. http://dx.doi.org/10.1134/s1063785014030237.

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Lenardt, Maria Helena, Clóris Regina Blanski Grden, Jacy Aurélia Vieira de Sousa, Péricles Martim Reche, Susanne Elero Betiolli, and Dâmarys Kohlbeck de Melo Neu Ribeiro. "Factors associated with loss of handgrip strength in long-lived elderly." Revista da Escola de Enfermagem da USP 48, no. 6 (December 2014): 1006–12. http://dx.doi.org/10.1590/s0080-623420140000700007.

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Objective To investigate the prevalence of reduced grip strength and associated factors in long-lived elderly, who are users of primary health care. Method Cross-sectional quantitative study, data were collected during the period of January to December of 2013, by applying tests and questionnaires. The convenience sampling was comprised of 157 seniors. Results The findings indicate that the reduction in grip strength presents a moderate prevalence (25.5%), predominantly among females (19.1%), in the age group of 80-89 years (18.5%) and in those with lower educational levels (15.9%). The association between reduced grip strength and the variables of age and body mass index showed a statistical significance. Conclusion Investigations about the handgrip strength are essential for identifying clinical conditions of Brazilian long-lived elderly, and contribute to the development of plans towards the management of frailty.

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Lee, Jae, Taesu Yim, Hyouck Kim, Sungkook Hong, Doo Seo, and Hong Kim. "Investigation on Long Term Operation of Thermochemical Heat Storage with MgO-Based Composite Honeycombs." Energies 12, no. 7 (April 2, 2019): 1262. http://dx.doi.org/10.3390/en12071262.

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The efficient storing and utilizing of industrial waste heat can contribute to the reduction of CO2 and primary energy. Thermochemical heat storage uses a chemical and/or an adsorption-desorption reaction to store heat without heat loss. This study aims to assess the long-term operational feasibility of thermochemical material based composite honeycombs, so that a new thermochemical heat storage and peripheral system were prepared. The evaluation was done by three aspects: The compressive strength of the honeycomb, heat charging, and the discharging capabilities of the thermochemical heat storage. The compressive strength exceeded 1 MPa and is sufficient for safe use. The thermal performance was also assessed in a variety of ways during 100 cycles, 550 h in total. By introducing a new process, the amount of thermochemical-only charging was successfully measured for the first time. Furthermore, the heat charging capabilities were measured at 55.8% after the end of the experiment. Finally, the heat discharging capability was decreased until 60 cycles and there was no further degradation thereafter. This degradation was caused by charging at a too high temperature (550 °C). In comparative tests using a low temperature (450 °C), the performance degradation became slow, which means that it is important to find the optimal charging temperature.

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Vogel, Frederick, Leah Braun, German Rubinstein, Stephanie Zopp, Sarina Benedix, Holger Schneider, Katrin Ritzel, et al. "Patients with low IGF-I after curative surgery for Cushing’s syndrome have an adverse long-term outcome of hypercortisolism-induced myopathy." European Journal of Endocrinology 184, no. 6 (June 1, 2021): 813–21. http://dx.doi.org/10.1530/eje-20-1285.

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Background Glucocorticoid excess leads to muscle atrophy and weakness in patients with endogenous Cushing’s syndrome. Insulin-like growth factor I (IGF-I) is known to have protective effects on muscle loss. We hypothesized that individual serum IGF-I concentrations might be predictive for long-term myopathy outcome in Cushing’s syndrome. Patients and methods In a prospective longitudinal study of 31 patients with florid Cushing’s syndrome, we analyzed IGF-I and IGF binding protein 3 (IGFBP 3) concentrations at the time of diagnosis and following surgical remission over a period of up to 3 years. We assessed muscle strength by grip strength measurements using a hand grip dynamometer and muscle mass by bio-impedance measurements. Findings Individual serum IGF-I concentrations in the postoperative phase were strongly predictive of long-term grip strength outcome (rs = 0.696, P ≤ 0.001). Also, lower IGF-I concentrations were associated with a lower muscle mass after 3 years (rs = 0.404, P = 0.033). While patients with high IGF-I s.d. scores (SDS; >1.4) showed an improvement in grip strength within the follow-up period (P = 0.009), patients with lower IGF-I SDS (≤−0.4) had a worse outcome with persisting muscle dysfunction. In contrast, preoperative IGF-I concentrations during the florid phase of Cushing’s syndrome did not predict long-term muscle function outcome (rs = 0.285, P = 0.127). Conclusion Lower individual IGF-I concentrations 6 months after curative surgery for Cushing’s syndrome are associated with adverse long-term myopathy outcome and IGF-I might be essential for muscle regeneration in the early phase after correction of hypercortisolism.

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Consoli, Nilo Cesar, Rodrigo Beck Saldanha, and Hugo Carlos Scheuermann Filho. "Short- and long-term effects of sodium chloride on strength and durability of coal fly ash stabilized with carbide lime." Canadian Geotechnical Journal 56, no. 12 (December 2019): 1929–39. http://dx.doi.org/10.1139/cgj-2018-0696.

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The research presented aims to quantify the influence of the curing period (t), dry unit weight (γd), lime amount (L), and the addition of sodium chloride (NaCl) on the short- and long-term behaviors of coal fly ash – carbide lime blends. Strength and wet–dry durability tests were carried out for differing values of porosity (η), L, and curing time (t) on mixtures that either contained small amounts of NaCl or contained none. Addition of NaCl to the mixtures resulted in significant increase in early strength gain when compared to specimens without NaCl, which demand longer curing periods to reach similar strength values. The addition of NaCl to coal fly ash – carbide lime blends reduced the accumulated loss of mass (ALM) after 12 wet–dry brushing cycles for specimens at early stages of curing (about 50% for 7 days). Equivalence in the unconfined compressive strength (qu) and ALM(after 12 wet–dry cycles) between the specimens with and without NaCl is achieved in the long term. Finally, a variance analysis performed regarding qu and ALM results yielded that the order of importance of the controllable factors changed from t, NaCl addition, γd, and L for strength to γd, t, NaCl addition, and L for ALM(after 12 wet–dry cycles).

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Li, Ying Tao, Ling Zhou, Yu Zhang, Jing Wei Cui, and Jun Shao. "Study on Long-Term Performance of Concrete Based on Seawater, Sea Sand and Coral Sand." Advanced Materials Research 706-708 (June 2013): 512–15. http://dx.doi.org/10.4028/www.scientific.net/amr.706-708.512.

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Experimental studies of the long-term performance such have been done in this paper for sea water and sea-sand concrete and sea water and coral sand concrete, such as the elastic modulus, frost resistance and corrosion of reinforcement behavior. The test results show that the compressive elastic modulus of the sea water and sea sand concrete and the sea water and coral sand concrete are slightly lower than that of ordinary concrete, while the adding of fly ash or ground slag in them lead the late compressive elastic modulus slight increase. Compared with the ordinary concrete after freeze-thaw cycle, the mass loss rate and the compressive strength loss rate of the sea water and sea sand concrete and coral sand concrete are slightly larger, but slightly reduced by mixing with ground slag in the concrete, while a little high by mixing with fly ash. Due to the presence of Cl- in the saltwater and sea sand concrete and coral sand concrete, [Cl-] / [OH-] values will be larger, which leads to corrosion of internal reinforced, so it is necessary to adopt appropriate ways to modification for the concrete and reinforced.

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Valenzuela, Pedro L., Adrián Castillo-García, Alejandro Lucia, and Fernando Naclerio. "Effects of Combining a Ketogenic Diet with Resistance Training on Body Composition, Strength, and Mechanical Power in Trained Individuals: A Narrative Review." Nutrients 13, no. 9 (September 1, 2021): 3083. http://dx.doi.org/10.3390/nu13093083.

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Ketogenic diets (KD) have gained popularity in recent years among strength-trained individuals. The present review summarizes current evidence—with a particular focus on randomized controlled trials—on the effects of KD on body composition and muscle performance (strength and power output) in strength-trained individuals. Although long-term studies (>12 weeks) are lacking, growing evidence supports the effectiveness of an ad libitum and energy-balanced KD for reducing total body and fat mass, at least in the short term. However, no or negligible benefits on body composition have been observed when comparing hypocaloric KD with conventional diets resulting in the same energy deficit. Moreover, some studies suggest that KD might impair resistance training-induced muscle hypertrophy, sometimes with concomitant decrements in muscle performance, at least when expressed in absolute units and not relative to total body mass (e.g., one-repetition maximum). KD might therefore be a beneficial strategy for promoting fat loss, although it might not be a recommendable option to gain muscle mass and strength/power. More research is needed on the adoption of strategies for avoiding the potentially detrimental effect of KD on muscle mass and strength/power (e.g., increasing protein intake, reintroduction of carbohydrates before competition). In summary, evidence is as yet scarce to support a major beneficial effect of KD on body composition or performance in strength-trained individuals. Furthermore, the long-term effectiveness and safety of this type of diet remains to be determined.

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Sartor, Lorena Cristina Alvarez, Gustavo José Luvizutto, Juli Thomaz de Souza, Evelin Roberta Silva Dalle Molle, Gabriel Pinheiro Modolo, Taís Regina da Silva, Robson Aparecido Prudente, et al. "Respiratory Function and Grip Strength in the Acute Phase of Stroke Are Associated with Stroke Severity and Disability at Hospital Discharge." Rehabilitation Research and Practice 2020 (February 3, 2020): 1–10. http://dx.doi.org/10.1155/2020/1636540.

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Introduction. Stroke can lead to musculoskeletal and respiratory dysfunction, chronic deconditioning, and functional limitations, as well as long-term complications. Objective. The aim of this study was to evaluate the association between respiratory function and grip strength in the acute phase of stroke and stroke severity, disability, and autonomy in the long term. Methods. This was a cohort study including 46 patients in the stroke unit. The stroke patients were assessed in the stroke unit at the following moments: at admission by the clinical and haemodynamic stability, demographic and anthropometric data, hand grip strength, stroke severity by National Institutes of Health Stroke Scale (NIHSS) score, and respiratory function using a manovacuometer; during hospitalization by clinical complications and the length of stay; and at hospital discharge and 90 days after discharge by the degrees of functional capacity and dependence using NIHSS, modified Rankin scale (mRs), and Barthel index. Data analysis was performed by multiple linear regression to verify the association between respiratory function and grip strength and the outcomes. Results. The median length of stay in the stroke unit was 7 days. A negative correlation was found between the palmar prehension strength on the unaffected side and mRs at discharge (β=‐0.034, p=0.049). The NIHSS scores at discharge (β=‐0.016, p=0.011) were negatively correlated with the MEP. The Barthel index at discharge was positively correlated with the palmar prehension strength on the unaffected side (β=0.480, p=0.023). Conclusion. It was concluded that a loss of grip strength is associated with a loss of ability and autonomy at discharge and poor respiratory function is associated with stroke severity at discharge.

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Šál, Jiří. "Testing of brick clay modifications as a raw material for building ceramic products." MATEC Web of Conferences 279 (2019): 02022. http://dx.doi.org/10.1051/matecconf/201927902022.

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Brick clay is nowadays modified by various procedures to achieve the best properties when used for building ceramic products. In the treatment of these clays, the properties are regulated by changing the quantity of water, sharpening, lightening, venting, settling, using additives, but also by consistent homogenization, crushing, grinding and mixing. This article compares several clay bricks before and after treatment and also compares them with ceramic clay. Comparative parameters are bulk density, porosity, water absorption, compressive strength and flexural strength, long-term changes in burning and weight loss by burning.

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Franck, R. E., J. A. Hawk, and G. J. Shiflet. "Microstructural characterization of a rapidly solidified Al-Fe-V-Si alloy for elevated temperature applications." Proceedings, annual meeting, Electron Microscopy Society of America 46 (1988): 550–51. http://dx.doi.org/10.1017/s0424820100104819.

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Rapid solidification processing (RSP) is one method of producing high strength aluminum alloys for elevated temperature applications. Allied-Signal, Inc. has produced an Al-12.4 Fe-1.2 V-2.3 Si (composition in wt pct) alloy which possesses good microstructural stability up to 425°C. This alloy contains a high volume fraction (37 v/o) of fine nearly spherical, α-Al12(Fe, V)3Si dispersoids. The improved elevated temperature strength and stability of this alloy is due to the slower dispersoid coarsening rate of the silicide particles. Additionally, the high v/o of second phase particles should inhibit recrystallization and grain growth, and thus reduce any loss in strength due to long term, high temperature annealing.The focus of this research is to investigate microstructural changes induced by long term, high temperature static annealing heat-treatments. Annealing treatments for up to 1000 hours were carried out on this alloy at 500°C, 550°C and 600°C. Particle coarsening and/or recrystallization and grain growth would be accelerated in these temperature regimes.

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Tateiwa, Toshiyuki, Elia Marin, Alfredo Rondinella, Marco Ciniglio, Wenliang Zhu, Saverio Affatato, Giuseppe Pezzotti, et al. "Burst Strength of BIOLOX®delta Femoral Heads and Its Dependence on Low-Temperature Environmental Degradation." Materials 13, no. 2 (January 12, 2020): 350. http://dx.doi.org/10.3390/ma13020350.

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Zirconia-toughened alumina (ZTA) currently represents the bioceramic gold standard for load-bearing components in artificial hip joints. ZTA is long known for its high flexural strength and fracture toughness, both properties arising from a microscopic crack-tip shielding mechanism due to the stress-induced tetragonal-to-monoclinic (t→m) polymorphic transformation of zirconia. However, there have been concerns over the years regarding the long-term structural performance of ZTA since the t→m transformation also spontaneously occurs at the material’s surface under low-temperature environmental conditions with a concomitant degradation of mechanical properties. Spontaneous surface degradation has been extensively studied in vitro, but predictive algorithms have underestimated the extent of in vivo degradation observed in retrievals. The present research focused on burst-strength assessments of Ø28 mm ZTA femoral before and after long-term in vitro hydrothermal ageing according to ISO 7206-10. An average burst strength of 52 kN was measured for pristine femoral heads. This value was ~36% lower than results obtained under the same standard conditions by other authors. A further loss of burst strength (~13% in ultimate load) was observed after hydrothermal ageing, with increased surface monoclinic content ranging from ~6% to >50%. Nevertheless, the repetitively stressed and hydrothermally treated ZTA heads exceeded the minimum burst strength stipulated by the US Food and Drug Administration (FDA) despite severe test conditions. Lastly, Raman spectroscopic assessments of phase transformation and residual stresses on the fracture surface of the femoral heads were used to clarify burst-strength fluctuations and the effect of hydrothermal ageing on the material’s overall strength degradation.

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Linfante, Italo, Francesca Tari Capone, Guilherme Dabus, Sergio Gonzalez-Arias, Patricio E. Lau, and Edgar A. Samaniego. "Spinal arteriovenous malformation associated with spinal metameric syndrome: a treatable cause of long-term paraplegia?" Journal of Neurosurgery: Spine 16, no. 4 (April 2012): 408–13. http://dx.doi.org/10.3171/2011.12.spine11636.

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Cutaneomeningospinal angiomatosis, or Cobb syndrome, is a rare metameric developmental disorder presenting as an extradural-intradural vascular malformation that involves bone, muscle, skin, spinal cord, and nerve roots. A 14-year-old girl with a red nevus involving the T6–9 dermatomes on the left side of her back presented with a 5-year history of bowel and bladder incontinence, paraplegia, and lower-extremity sensory loss. Magnetic resonance imaging demonstrated a hemangioma in the T-8 and T-9 vertebral bodies and a spinal cord AVM nidus extending from T-6 to T-9. The AVM was successfully embolized and the patient regained lower-extremity strength, ambulation, and normal sphincter functions after 5 years of having been wheelchair bound. The authors report the restoration of ambulation after endovascular embolization of a large spinal AVM in a patient with long-standing paraplegia due to Cobb syndrome.

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Rachner, Tilman D., Andy Göbel, Nikolai P. Jaschke, and Lorenz C. Hofbauer. "Challenges in Preventing Bone Loss Induced by Aromatase Inhibitors." Journal of Clinical Endocrinology & Metabolism 105, no. 10 (July 16, 2020): 3122–33. http://dx.doi.org/10.1210/clinem/dgaa463.

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Abstract Context: Aromatase inhibitors have become a mainstay in the adjuvant treatment regimen in postmenopausal women with hormone receptor–positive breast cancer. While many of these patients have an excellent long-term prognosis, adverse effects on bone represent an emerging complication of aromatase inhibitor treatment, resulting in substantial bone loss and fragility fractures. Treatment approaches to prevent aromatase inhibitor–induced bone loss typically consist of an antiresorptive approach with bisphosphonates or the RANKL antibody denosumab. However, different guidelines vary with respect to treatment thresholds, duration, and dosing. The choice of antiresorptive regime is further complicated by comorbidities and potential disease-modifying effects of individual agents. Objective: This review summarizes the evidence of how aromatase inhibitors affect bone health and provides an update of clinical approaches to preserve bone strength in affected women. (J Clin Endocrinol Metab XX: 0–0, 2020)

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Yang, Jun, Tong Guo, and Aiqun Li. "Experimental investigation on long-term behavior of prestressed concrete beams under coupled effect of sustained load and corrosion." Advances in Structural Engineering 23, no. 12 (May 11, 2020): 2587–96. http://dx.doi.org/10.1177/1369433220919067.

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Prestressed concrete beams are widely used in construction, while they may be attacked by the corrosion medium during the service. Past research works show that coupled effect of high stress and corrosion can significantly deteriorate the performance of prestressed concrete structures. This article presents an experimental investigation on long-term behavior of prestressed concrete beams under the coupled effect of sustained load and corrosion. During the accelerated corrosion process, six prestressed concrete beams were subjected to different levels of sustained loads, and time-dependent prestress loss and concrete stains were recorded and analyzed. It is observed that the local corrosion (i.e. pitting corrosion) of the steel strands was significantly affected by the sustained load level, and the coupled effect led to more serious damage on the beams than individual sustained load or corrosion. Bending loads were finally applied to investigate the influence of corrosion on flexural capacities of these beams. It was found that the flexural capacities and failure mode of the beams were significantly influenced by corrosion. Meanwhile, the corrosion has more significant effect on tension strength of strands rather than bond strength.

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Verbist, Maxime, Jorge M. Branco, and Lina Nunes. "Characterization of the Mechanical Performance in Compression Perpendicular to the Grain of Insect-Deteriorated Timber." Buildings 10, no. 1 (January 19, 2020): 14. http://dx.doi.org/10.3390/buildings10010014.

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Among biological agents, insect attacks may cause severe degradation of timber structures in the service life of buildings which leads to lower mechanical performance and, thus, maintenance problems over time. Additionally, compression perpendicular to the grain always features a weak spot with respect to the long-term mechanical performance of timber members and joints. In the present work, the respective strength and elastic modulus were thus investigated for insect deteriorated wood. Following a standardized geometry, small samples degraded by anobiids were extracted from beams made of sweet chestnut wood (Castanea sativa Mill.) that were removed from service. Visual assessment of the external wood surfaces was then performed to identify areas infested by insects. Afterwards, destructive monotonic compression tests were carried out perpendicularly to the grain on the damaged area to determine the loss of compressive strength and elastic modulus. The experimental results showed that the loss of compressive strength and elastic modulus might be linearly correlated to the wood density loss for small samples infested by insects. Nonetheless, future work should focus on determining accurately the density loss in the insect-deteriorated part through non- or semi-destructive tests, in order to establish stronger relationships with the mechanical properties loss investigated.

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Aoki, Kai, Masaki Konno, Katsunari Honda, Takuya Abe, Takeshi Nagata, Masaaki Takehara, Takehito Sugasawa, Kazuhiro Takekoshi, and Hajime Ohmori. "Habitual Aerobic Exercise Diminishes the Effects of Sarcopenia in Senescence-Accelerated Mice Prone8 Model." Geriatrics 5, no. 3 (September 9, 2020): 48. http://dx.doi.org/10.3390/geriatrics5030048.

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Loss of muscle mass and strength are progressing with aging. Exercise is a beneficial method to prevent physical dysfunction, and habitual exercise can improve the muscle quality. Therefore, we evaluated the effects of long-term habitual exercise’s impact on sarcopenia utilizing the senescence-accelerated mice prone8 (SAMP8) model. Notably, 27 w SAMP8 were used in this study. Mice were classified into 28 (28 w) and 44 weeks old. The 44-week group was divided into the sedentary group (44 w) and a group exercising for 16 weeks (44 w + Ex). The 44 w + Ex performed habitual exercise from 28 to 44 weeks. Additionally, grip strength tests were performed with mice aged 28 and 44 weeks. Muscles were harvested and measured muscle weight at 44 w. Gastrocnemius decreased in 44 w, but was unchanged in 44 w + Ex. There was a trend for lower muscle grip strength in the 44 w group, but there was no change in 44 w + Ex. The phosphorylation levels of Akt and p70S6K as a protein synthesis marker were decreased in 44 w. Cytochrome c oxidase subunit IV (CoxIV) mRNA and protein levels decreased in 44 w. These results suggested that long-term habitual exercise attenuates muscle mass and strength decline, possibly through maintenance of muscle protein synthesis and mitochondrial maintenance.

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Haefele, Peter, and Oscar Herrera. "Strength and Stiffness Degradation of Carbon Fiber Reinforced Plastic under Cyclic Loading under Membran-, Shear- and Bending Loading." Materials Science Forum 825-826 (July 2015): 968–75. http://dx.doi.org/10.4028/www.scientific.net/msf.825-826.968.

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In order to meet the increasing lightweight requirements, the application of fiber reinforced plastics is indispensable. To ensure the structural durability of the car or machine under operational conditions, it is essential to know the long term behavior of carbon fiber reinforced plastic material (CFRP) under the numerous influencing factors under fatigue loading. For a reliable safety assessment of the car structure under operational conditions, the degradation of the stiffness and of the static strength after a certain damage due to cyclic loading is of particular importance. The paper covers the loss of stiffness and remaining strength as a function of fatigue damage for specimen and components under membrane, shear and bending loading. The tests are done using different layer set-ups (unidirectional, angle ply, quasiisotropic) and various loading conditions (membrane, shear and bending loading). In order to account for the transferability, the tests are carried out using specimen and components (hat sections). Both specimen and components show a significant loss in strength and stiffness.

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Obál, Izabella, Bernát Nógrádi, Valéria Meszlényi, Roland Patai, Gerda Ricken, Gabor G. Kovacs, Kornélia Tripolszki, Márta Széll, László Siklós, and József I. Engelhardt. "Experimental Motor Neuron Disease Induced in Mice with Long-Term Repeated Intraperitoneal Injections of Serum from ALS Patients." International Journal of Molecular Sciences 20, no. 10 (May 25, 2019): 2573. http://dx.doi.org/10.3390/ijms20102573.

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In an earlier study, signs of commencing degeneration of spinal motor neurons were induced in mice with short-term intraperitoneal injections of immunoglobulin G (IgG) taken from patients with amyotrophic lateral sclerosis (ALS). Since in that study, neither weakness nor loss of motor neurons was noted, to test whether the ALS IgG in this paradigm has the potential to evoke relentless degeneration of motor neurons, treatment with repeated injections over a longer period was carried out. Mice were systematically injected intraperitoneally with serum taken from ALS patients over a 75-day period. At selected time points, the isometric force of the limbs, number of spinal motor neurons and their intracellular calcium levels were determined. Furthermore, markers of glial activation and the motoneuronal uptake of human IgG were monitored. During this period, gliosis and progressive motoneuronal degeneration developed, which led to gradual loss of spinal motor neurons, more than 40% at day 21, along with decreasing muscle strength in the limbs. The inclusion-like accumulation of IgG appeared in the perikarya with the increase of intracellular calcium in the cell bodies and motor nerve terminals. Our results demonstrate that ALS serum can transfer motor neuron disease to mice.

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Gao, Kun Yuan, Zuo Ren Nie, Huang Hui, Sheng Ping Wen, Xiao Lan Wu, and Yu Sheng Ding. "The Effect of Heat Treatment on the Long-Term Corrosion Resistance in Er Containing 5083 Cold Rolled Sheets." Materials Science Forum 794-796 (June 2014): 199–204. http://dx.doi.org/10.4028/www.scientific.net/msf.794-796.199.

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The effect of heat treatment on the long-term corrosion resistance of Er containing 5083 aluminum alloy was studied using the micro-hardness test and mass loss test. The microstructure was analyzed by TEM. To maintain the strength, the annealing temperature was selected to be 100-230°C below the recrystallization onset temperature determined by the micro-hardness test. The plot of the annealing temperature versus the Intergranular Corrosion (IGC) initial time, which is determined by the Nitric Acid Mass Loss Test, showed a C-curve. The shortest IGC initial time (~1h) happened at 175°C, the nose temperature of the C-curve. When annealed at 125-200°C, the samples were IGC sensitive with the initial time less than 3h. The entirely IGC resistant (stabilized) samples were obtained when annealed at 220-230°C. The 175°C sensitized treatment was performed on the 220°C-stabilized samples, which showed that the 3-12h stabilization could significantly improve the resistance for long-term corrosion. TEM results showed that, for the IGC sensitive samples, β phases (Al3Mg2) grew along the grain boundary continuously, while for the stabilized samples, they were isolated on triangle grain boundary and phase boundary.

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Gowthaman, Sivakumar, Kazunori Nakashima, and Satoru Kawasaki. "Durability analysis of bio-cemented slope soil under the exposure of acid rain." Journal of Soils and Sediments 21, no. 8 (June 11, 2021): 2831–44. http://dx.doi.org/10.1007/s11368-021-02997-w.

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Abstract Purpose Instability of slope surface is a critical concern in Geotechnical and Environmental Engineering. MICP (Microbial-Induced Carbonate Precipitation), an innovative bio-cementation technique, has attracted the attention for slope surface protection. In this work, MICP was investigated to evaluate its durability under the exposure of acid rain and to advance the understanding on long-term performance of slope soil preserved by MICP. Methods MICP treatment was applied to a fine-grained slope soil using indigenous bacteria. Specimens treated to different cementation levels (% CaCO3) were exposed to acid rain (of varying pH) through two sorts of mechanisms: (i) infiltration and (ii) immersion. The evaluations were based on corrosion of CaCO3, mass loss, needle penetration tests, and scanning electron microscopy. Results The decrease in pH increased the corrosion of CaCO3, resulting in considerable loss in aggregate and unconfined compressive strength. However, increased cementation level showed high durability of specimens. The soils treated to 12.5% CaCO3 showed 19.9% soil loss, whereas it was reduced to 5.4% when cemented to 22.5% CaCO3. The results also revealed that the contact time of acid rain significantly governed the rate of corrosion, i.e., specimens subjected to lower infiltration rate (20 mm/h) showed higher loss of mass compared to that of higher rate (100 mm/h). Conclusion The long-term performance of MICP treatment is determined by (i) cementation level, (ii) pH, and (iii) infiltration rate of acid rain. High cementation level promotes the longevity of the treatment. Therefore, MICP to higher cementation level is recommended for long-term preservation of slope surface.

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Ferreira, Eduardo, Katrien Hendrix, Nele Bleyen, Elie Valcke, Erik Coppens, Katrien Meert, and Seif Ben Hadj Hassine. "Durability tests on plasma treated surrogate cemented concentrates and resins." MRS Advances 5, no. 3-4 (December 26, 2019): 149–58. http://dx.doi.org/10.1557/adv.2019.478.

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AbstractPlasma incineration might be a promising technique for the conditioning of various radioactive waste streams. Assessing the long-term durability of the plasma slag is essential to predict its performance during long-term disposal. In this paper, the stability of six plasma treated surrogate cemented concentrates or resins in a high pH environment is investigated. The slags were crushed (2 different granulometries) and immobilized in a cement matrix, after which samples were submitted to long-term durability tests (stability under water at 20 °C; stability in a high relative humidity environment at 38 °C) and to an accelerated Alkali-Silica-Reaction (ASR) test (1 M NaOH at 80 °C). The first results show that the expansion and strength loss of the cement-slag mixtures remain limited in the test conditions, although differences between the different materials and granulometries could be perceived. No visual damage was observed. Some tests are still ongoing and will last 2 years.

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Zhang, Qian, Bin Chen, Fuhua Yan, Jianbin Guo, Xiaofeng Zhu, Shouzhi Ma, and Wenrong Yang. "Interleukin-10 Inhibits Bone Resorption: A Potential Therapeutic Strategy in Periodontitis and Other Bone Loss Diseases." BioMed Research International 2014 (2014): 1–5. http://dx.doi.org/10.1155/2014/284836.

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Periodontitis and other bone loss diseases, decreasing bone volume and strength, have a significant impact on millions of people with the risk of tooth loss and bone fracture. The integrity and strength of bone are maintained through the balance between bone resorption and bone formation by osteoclasts and osteoblasts, respectively, so the loss of bone results from the disruption of such balance due to increased resorption or/and decreased formation of bone. The goal of therapies for diseases of bone loss is to reduce bone loss, improve bone formation, and then keep healthy bone density. Current therapies have mostly relied on long-term medication, exercise, anti-inflammatory therapies, and changing of the life style. However there are some limitations for some patients in the effective treatments for bone loss diseases because of the complexity of bone loss. Interleukin-10 (IL-10) is a potent anti-inflammatory cytokine, and recent studies have indicated that IL-10 can contribute to the maintenance of bone mass through inhibition of osteoclastic bone resorption and regulation of osteoblastic bone formation. This paper will provide a brief overview of the role of IL-10 in bone loss diseases and discuss the possibility of IL-10 adoption in therapy of bone loss diseases therapy.

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Wallner, C., J. M. Wagner, S. Dittfeld, M. Drysch, M. Lehnhardt, and B. Behr. "Myostatin serum concentration as an indicator for deviated muscle metabolism in severe burn injuries." Scandinavian Journal of Surgery 108, no. 4 (November 25, 2018): 297–304. http://dx.doi.org/10.1177/1457496918812230.

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Introduction: Patients experiencing thermal injuries with an extent of over 20% of total body surface area suffer from systemic catabolic disease. The thermal trauma-induced loss of muscle mass causes a higher incidence for comorbidities and subsequently a higher mortality. In this study, we aimed to investigate the role of myostatin in the interplay with follistatin during muscle cachexia. Methods: Patients with burn injuries (>10% total body surface area) between the ages of 18 and 75 were prospectively included within the first 48 h after trauma to determine deviations of parameters connected to muscle catabolism. In the chronic state of burn injury (9–12 months after trauma), we re-evaluated myostatin and follistatin concentrations as well as muscle strength of the non-dominant forearm. Results: We were able to show a time-dependent alteration (9–12 months after burn injury) of myostatin with an initial decrease ( p < 0.001) and long-term increase ( p < 0.001) after thermal injury in blood serum. For follistatin, a reciprocal correlation was observed ( r = −0.707, p = 0.001). Accordingly, muscle strength of the non-dominant hand and forearm was significantly decreased 9–12 months after injury in post-burn patients compared with healthy patients with a significant correlation to myostatin levels ( r = −0.899, p < 0.001). In addition, initial myostatin serum concentration was predictive for long-term muscle strength impairment. Conclusion: With regard to the muscle metabolism after thermal trauma, our data suggest an acute anabolic response, presumably to spare muscle mass, which is converted to catabolic conditions accompanied by muscle strength reduction in the chronic phase. Myostatin plays a crucial role in this orchestration and initial myostatin concentration may predict the long-term muscle strength.

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Hernández-Álvarez, David, Beatriz Mena-Montes, Rafael Toledo-Pérez, Gibrán Pedraza-Vázquez, Stefanie Paola López-Cervantes, Alfredo Morales-Salazar, Edith Hernández-Cruz, et al. "Long-Term Moderate Exercise Combined with Metformin Treatment Induces an Hormetic Response That Prevents Strength and Muscle Mass Loss in Old Female Wistar Rats." Oxidative Medicine and Cellular Longevity 2019 (November 11, 2019): 1–14. http://dx.doi.org/10.1155/2019/3428543.

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Sarcopenia is a syndrome characterized by a progressive and generalized skeletal muscle mass and strength loss, as well as a poor physical performance, which as strongly been associated with aging. Sedentary lifestyle in the elderly contributes to this condition; however, physical activity improves health, reducing morbidity and mortality. Recent studies have shown that metformin (MTF) can also prevent muscle damage promoting muscular performance. To date, there is great controversy if MTF treatment combined with exercise training improves or nullifies the benefits provided by physical activity. This study is aimed at evaluating the effect of long-term moderate exercise combined with MTF treatment on body composition, strength, redox state, and survival rate during the life of female Wistar rats. In this study, rats performed moderate exercise during 20 of their 24 months of life and were treated with MTF for one year or for 6 months, i.e., from 12 to 24 months old and 18 to 24 months old. The body composition (percentage of fat, bone, and lean mass) was determined using a dual-energy X-ray absorption scanner (DXA), and grip strength was determined using a dynamometer. Likewise, medial and tibial nerve somatosensory evoked potentials were evaluated and the redox state was measured by HPLC, calculating the GSH/GSSG ratio in the gastrocnemius muscle. Our results suggest- that the MTF administration, both in the sedentary and the exercise groups, might activate a mechanism that is directly related to the induction of the hormetic response through the redox state modulation. MTF treatment does not eliminate the beneficial effects of exercise throughout life, and although MTF does not increase muscle mass, it increases longevity.

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Goroshko, A., V. Royzman, and S. Petraschuk. "Simulation of a thin long rod that does not have critical forces and does not lose stability to Euler." Problems of tribology 97, no. 3 (September 28, 2020): 25–31. http://dx.doi.org/10.31891/2079-1372-2020-97-3-25-31.

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The paper proposes a method of preventing the loss of Euler stability by thin rods. Such rods do not have critical forces and therefore do not lose stability from longitudinal compressive force. The method is based on a temporary change in the stiffness of the rod-support system, in particular, a change in the length of the rod between the supports when approaching the value of critical forces, and after passing the return to the previous value. The results of simulation modeling of the rod behavior are presented, which confirm the possibility to eliminate the loss of its stability with increasing compressive force to the maximum allowable value, which is determined from the condition of strength.

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Journal articles on the topic 'Long-term loss of strength'

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