Water Of Different Temperatures Research Articles

Influence of temperature on twitch potentiation following submaximal voluntary contractions in human plantar flexor muscles.

This study aimed to clarify the influence of temperature on post-activation twitch potentiation, a possible indicator of fast-twitch fiber activation during a preceding voluntary contraction. Ten healthy males immersed their left lower leg in water of different temperatures (cold: 0°C, neutral: 32-35°C, hot: ~43°C) for 20 min each. In each temperature condition, they performed submaximal (10%-50% of maximal voluntary contraction torque measured before water immersion) and maximal plantar flexions. Immediately after each voluntary contraction, twitch contractions were evoked with supramaximal stimulation of the posterior tibial nerve. The magnitude of twitch potentiation, defined as a percent increase in twitch torque following a voluntary contraction, increased with the intensity of the preceding voluntary contraction. The magnitude of twitch potentiation after the maximal voluntary contraction was smaller in Cold than in the other temperature conditions. However, temperature had no influence on the relative magnitude of twitch potentiation following the submaximal contractions. In addition, there was no difference in electromyographic activity between the gastrocnemius and soleus muscles in any temperature conditions. Collectively, the temperature dependence was not observed when using twitch potentiation or electromyographic amplitude as an indicator of fast-twitch fiber activation during brief submaximal voluntary contractions.

非麻痺側上肢を用いた感覚弁別課題により右上肢の痛みが軽減した左脳出血の一症例

[Purpose] This paper reports a case in which sensory discrimination tasks performed using the nonparalyzed and paralyzed upper limbs, in this order, effectively reduced pain in the latter. [Participant and Methods] The patient was a 40-year-old female with a complaint of pain at rest in her right upper limb 6 months after left cerebral hemorrhage. As various symptoms such as allodynia were present, complex regional pain syndrome (CRPS) type 1 was determined to be the cause of the pain. The therapeutic approaches included: a tactile discrimination task using balls that varied in hardness, surface roughness, and size; and a hot-cold discrimination task using water of different temperatures. The patient performed these tasks for 30 minutes each day for a period of 1 week, with her non-paralyzed upper limb first, and then with her paralyzed upper limb. [Results] The patient’s correct answer rate was higher than when she used only her paralyzed upper limb. Within 1 week of intervention, her right upper limb pain at rest was reduced. [Conclusion] The results support the effectiveness of sensory discrimination tasks also using the non-paralyzed upper limb when it is difficult to perform these tasks with the paralyzed upper limb only.

Growth characteristics of shallots and absorption of Mg ions dissolved from serpentinites

Magnesium (Mg)-rich water or food is highly beneficial to human health. Shallots are used in cooking, have simple growth conditions and have a short growth cycle. In this study, natural serpentinite was ground into powder (particle size: 50–200 nm), heated at high temperatures (400 and 800°C) and then dissolved in water of different temperatures (25, 60 and 100°C) to prepare natural magnesium-containing water. The experimental results indicated that natural serpentine minerals contain magnesium silicate, which has ionic properties and a high electrical conductivity. The dissolution of magnesium ions increased with the temperature of the distilled water. The heat-treated powder displayed higher crystallinity. However, the dissolution of magnesium was lower for the solution containing the powder heated to 800°C than for the solution containing the powder heated to 400°C. The 400°C powder exhibited favorable crystallinity and a low level of impurities, and its interlayer spacing did not change. The shallots grown with natural magnesium-containing water (magnesium shallots) had a high concentration of magnesium ions in their white and green parts. Such shallots can be provided by food platforms, and eating such shallots can help one meet the daily magnesium intake requirement of 300 mg/l for humans.

SPECIAL RESEARCHES OF CLAY SOILS WHICH ARE NOT REGULATED ON NPP SITES

Problem statement. The article presents the results of special non-normative research for saline clay soils sampled from excavations during the nuclear power plants’ construction at different times and in different countries. Of the NPP sites located in the arid climate zone, only the Crimean NPP, which is not yet under construction, the planned NPP in Uzbekistan and possibly the NPP in Egypt are close to the engineering and geological conditions relative to the described NPP site to a large extent. The purpose of the article. The researches’ purpose is to estimate the degree of leakages impact from technological pipelines for production water of different composition and temperature, which affect the soil properties of the foundations for responsible buildings and structures of NPPs and other critical energy facilities. The need for such research is obvious to ensure the safe operation of nuclear power plants, especially when NPP are located in difficult seismotectonic and geological conditions. Conclusions. The non-regulated method for investigating the plastic properties of clay soils proposed in this article is a combination of several already tested research methods. The essence and difference of this indirect method is to investigate the soils plastic properties only after their pretreatment at different times with ground water of different temperatures. The test process partially simulates the impact on soil bases of possible short-term (instantaneous) or long-term leakages from technological thermal water supply communications, which would result in significant ground water warming. As a work result, the upper horizons of the soils for some NPP sites were prone to soaking, including at elevated temperatures, but no fundamental differences from these impacts have yet been found. The results of these researches correlate quite well with the previously performed investigations on soils leaching in the upper part of the geological section of the NPP sites. As a result, the upper soil horizons of some NPP sites were prone to soaking, including at elevated temperatures, but no fundamental differences from these effects have yet been identified. The results of the conducted research correlate quite well with the previously performed studies on soil leaching in the upper part of the NPP sites geological section.

Utilization of telecommunication optical routes to power fiber-optic polarization sensors

A single-mode telecommunication optical route can be used for reliable power supplies of a remote non-electric temperature fiber-optic polarization sensor, but the optical route, due to many physical factors, affects an immediate state of polarization during the transmission. This negative phenomenon changes the sensitivity of the sensor itself. The thesis proposes two main approaches to solving that problem. The first approach is based on the suitable connection of a depolarizer and linear polarizers. The second approach is based on signal interference, which takes place in a polarization-maintaining fiber coupler. This article also evaluates the advantages and disadvantages of the two approaches and graphically demonstrates the functionality of the fiber-optic sensor, which was tested by applying a container with water of different temperatures. A big advantage of this type of sensor is that it is not necessary to have components, that are dependent on electricity, near the monitored place, where there may be no access to electricity, or the place may be sensitive to an electric charge. Paper demonstrates the possibility of successfully powering the non-electric sensor via a classical optical route.

Therapeutic Aspects of Hydrotherapy: A Review

Hydrotherapy is a procedure where water of different temperatures are used to relieve pain and treat illness. This review describes about different conditions of water treatments. Hydrotherapy can help treat a variety of conditions, including arthritis, stomach problems, sleep disorders, stress and depression. The theory behind hydrotherapy is that water has healing properties that can mitigate various ailments and conditions. Different states of water such as ice, liquid, and steam is used in the treatment of various conditions. Water cure therapies comprise enema therapy, gel therapy etc. and also includes colonic hydrotropic, sitz bath, hydro-massage, wraps and compress methods. Cryotherapy, cold water immersion or ice bath could be a new treatment method thatis used by physical therapists, sports medicine facilities and rehab clinics.
 Bangladesh J Medicine July 2021; 32(2) : 138-141

STRENGTH CHARACTERISTICS OF POLYMER COMPOSITES BASED ON RECYCLED POLYPROPYLENE FILLED WITH RICE HUSK DURING MOISTURE ABSORPTION AND NATURAL AGIN

The relevance of the issue under investigation is conditioned by an increase of the ecological burden on the environment due to the continuous increase of plastic waste, a significant proportion of polypropylene. One solution to this problem is the involvement of recycled polypropylene to obtain plastic products based on composites filled with rice husk. It makes it possible to reduce the prime cost of finished products, regulate their physical and mechanical properties, and reduce the volume of difficult-to-decompose synthetic polymers that end up in waste. The key property of polypropylene, which changes during its filling with rice husk, is moisture absorption, which contributes to a change in the strength characteristics of the polymer composite and accelerates its aging under the influence of environmental factors. In this regard, this research aims to identify the patterns of the influence of absorbed moisture and natural aging on the physical and mechanical properties of polymer composites based on recycled polypropylene filled with rice husk. The leading approach to the study of this issue is laboratory tests on the saturation of polymer composites with water of different temperatures and duration of exposure and testing materials during long-term natural aging under the influence of environmental factors. The key factor characterizing the change in the physical and mechanical properties of materials, in this case, is the elasticity modulus, elongation, and tensile stress at the break during stretching of the prototypes. The materials of the paper are of practical value for the processing of secondary thermoplastic polymers, as well as the development of biodegradable polymer composites.

The correction of psychoemotional status in young people with overweight with increased consumption of mineral water

The aim. To study the influence of anthropometric indicators on the results of a drinking test with water of different temperatures, as well as on the psycho-emotional status.Materials and methods. The study involved 36 students. Conducted: measurement and calculation of basic anthropometric indicators, psychological testing using questionnaires, fasting drinking test with still water of different temperatures for four days with fixing the volume of liquids drunk. All examined students are divided into two groups according to the results of anthropometric examination.Results. The prevalence of overweight among students was 25,0%. Studies have shown the relationship between the main anthropometric indicators, the amount of fluid drunk and the temperature of the water taken, which indicate a violation of the relaxation accommodation of the stomach in individuals with a large amount of adipose tissue and% relative fat content. An increase in visceral hypersensitivity and a progressive deterioration of the relaxation accommodation of the stomach with an increase in the temperature of the received water were established. As a result of the work done, it was found that with an increase in BMI, a deterioration in well-being, an increase in depression, situational and personal anxiety and neurotization are observed. Overweight students with an increase in the volume and mass of total adipose tissue have a deterioration in mood and a greater tendency to depression. It was also proved the presence of a pronounced positive effect of drinking water on the human body with excess body weight, including its psychoemotional state.Conclusion. The results obtained make it possible to form anthropometric images of a person predisposed to disturbed accommodation of the stomach, taking into account gender, body weight and the nature of the distribution of adipose tissue. These studies confirmed a change in psychoemotional status depending on the main anthropometric indicators. The corrected effect of fasting drinking room-temperature water (30 °C) on the psycho-emotional state of overweight people is shown.

Mathematical estimation of fluid concentration in human skin during water immersion

IntroductionThe concentration of fluid and its analysis in human skin is innately a challenge due to its continuous movement and involvement in maximum life processes. The concentration of the fluid gets affected by the diffusion of fluids through the skin, which acts as the main barrier between the human body and the external environment. Therefore, it becomes imperative to study the process and impact of the diffusion of fluids through the skin. The problem becomes more interesting when the human body is immersed in water. ObjectivesThe present paper studies the change in the fluid distribution of human skin during its immersion in water of different temperatures. The application part of the paper visualizes various impaired vascular function and muscle soreness by water immersion during the physiotherapy treatment. MethodsA mathematical model based on the two-dimensional diffusion equation, along with appropriate boundary conditions, has been formulated. The maximum of the relevant parameters, such as fluid regulation, transfer coefficient, evaporation rate, etc., influencing the fluid distribution, have been incorporated. The model has been solved by variational finite element method, and numerical results have been obtained by the Crank-Nicholson scheme. ResultsThe increase in fluid concentration due to treatment with cold and acute hot water immersion has been noted, and the role of water immersion in enhancing the recovery in exercise-induced muscular damage has been analyzed. ConclusionsThe paper addressed the issue of rate of water diffusion through human skin, which otherwise couldn't be drawn from the analogy of gas diffusion through the membrane due to the variation in permeabilities of the two processes. The paper has applications in water immersion therapies and other activities like monitoring swimming induced pulmonary edema, etc.

A low-cost laboratory demonstration of the effects of temperature on the metabolism of an aquatic poikilotherm

ABSTRACT While metabolism is a fundamental process in physiology, the measurement of metabolism by living animals often requires specialized and expensive equipment. In 2016, I developed a novel laboratory exercise for animal physiology students where students were able to observe the effects of temperature and long-term temperature acclimation on the physiology of the Eastern grass shrimp, Palaemonetes paludosus. In this lab, grass shrimp were housed for 1 week at one of three temperatures, 20°C, 24°C, and 28°C. While grass shrimp encounter temperatures considerably colder than this in the wild, we were limited by the temperatures we could achieve without access to aquarium chillers. The students then moved shrimp into water of different temperatures and measured metabolic rates indirectly using heart rate and oxygen consumption. The initial results showed noticeable shifts in baseline metabolic rate over a relatively short, 2 week long acclimation period. In both heart rate and oxygen consumption, metabolic rates climbed predictably with temperature, consistent with the literature on responses in ectotherms. Also, consistent with the literature, the shrimp that were acclimated to warmer temperatures downregulated their metabolism to compensate, showing the lower metabolic rate at all three temperatures.

Survival of ESKAPE pathogen Acinetobacter baumannii in water of different temperatures and pH.

Bacterium Acinetobacter baumannii is an emergent pathogen associated with nosocomial infections, which can be also found in natural waters. The impact of ecological factors on A. baumannii is insufficiently investigated. The aim was to examine the influence of temperatures (-20 to 80 °C) and pH values (2 to 12) on the survival of environmental and clinical isolates of A. baumannii in nutrient-deprived spring water (SW) and nutrient-rich diluted nutrient broth during 5 months. A. baumannii successfully survived at -20 to 44 °C and neutral pH for 5 months, which is consistent with the persistence of this pathogen in the hospital environment. At temperatures 50 to 80 °C the survival of A. baumannii ranged from 5 days to 5 min. The pH 2 was the most lethal with survival time up to 3 hours, suggesting that acidic conditions are promising for disinfection of water contaminated with A. baumannii. Although the type of media was not statistically significant for long-time survival, the extensively resistant or pandrug-resistant isolates survived better in SW than susceptible or multidrug-resistant isolates. Two distinct colony phenotypes were recorded at extreme temperatures and pH values. The results of this study provide insight into the behaviour of this emerging pathogen in the environment.

Comparison of physical technologies for biomass control in biofilters treating gaseous toluene

ABSTRACTExcessive accumulation of biomass within gas-phase biofilters often results in the deterioration of removal performance. Compared with chemical and biological technologies, physical technologies are more effective in removing biomass and inducing less inhibition of the biofilter performance. This study applied different physical technologies, namely, air sparging, mechanical mixing, and washing with water at various temperatures, to remove excess biomass in biofilters treating toluene. Filter pressure drop, removed dry biomass, biofilter performance, and microbial metabolic characteristics were analyzed to evaluate the effectiveness of the methods. Results showed that air sparging was inefficient for biomass removal (1 kg dry biomass/m3 filter), whereas mechanical mixing significantly inhibited removal efficiencies (<30%). Washing of the packing with fluids was feasible, and hot fluids can remove a large amount of biomass. However, hot fluids reduce microbial activity and inhibit removal performance. Washing of the packing with either 20°C or 50°C water showed efficiency as >3 kg dry biomass/m3 filter can be removed at both temperatures with removal efficiencies at approximately 40% after treatment. Finally, different technologies were compared and summarized to propose an optimized strategy of biomass control for industrial biofilters.Implications: This study is to apply different physical technologies, namely, air sparging, mechanical mixing, and washing with water of different temperatures, to remove the excess biomass in biofilters treating toluene. The filter pressure drop, removed dry biomass, biofilter performance, and microbial metabolic characteristics were all analyzed to evaluate the effectiveness of the methods. The results of this study provide useful information regarding biomass control of industrial biofilters.

Heating Impact of a Tropical Reservoir on Downstream Water Temperature: A Case Study of the Jinghong Dam on the Lancang River

Reservoirs change downstream thermal regimes by releasing water of different temperatures to that under natural conditions, which may then alter downstream biodiversity and ecological processes. The hydropower exploitation in the mainstream Lancang-Mekong River has triggered concern for its potential effects on downstream countries, especially the impact of the released cold water on local fishery production. However, it was observed recently that the annual water temperature downstream of the Jinghong Reservoir (near the Chinese border) has increased by 3.0 °C compared to its historical average (1997–2004). In this study, a three-dimensional (3D) model of the Jinghong Reservoir was established to simulate its hydro- and thermodynamics. Results show that: (1) the impoundment of the Jinghong Reservoir contributed about 1.3 °C to the increment of the water temperature; (2) the solar radiation played a much more important role in comparison with atmosphere-water heat exchange in changing water temperatures; and (3) the outflow rate also imposed a significant influence on the water temperature by regulating the residence time. After impoundment, the residence time increased from 3 days to 11 days, which means that the duration that the water body can absorb solar radiation has been prolonged. The results explain the heating mechanism of the Jinghong Reservoir brought to downstream water temperatures.

Effect of water temperature on air-core generation and disappearance during draining

Understanding the air-core development during the draining of liquid from a cylindrical tank is of particular interest because this phenomenon has multiple engineering applications. In this study, experiments are performed for draining water of different temperatures from a cylindrical tank. Results show that the air-core generation and disappearance during draining depend on the temperature of the water in the tank, in which the total draining time increases with the water temperature. A correlation is proposed to predict the water height with time during draining. A numerical study is then performed for some of the temperature cases. Numerical and correlation results show a good agreement with the experimental data. Findings show that viscosity plays an important role behind the mechanism of air-core generation and disappearance phenomena.

Proportionally and non-proportionally perturbed fatigue of stainless steel

Computational fluid dynamics and finite element based simulation of the cyclic thermal shock loading caused by turbulent mixing of water of different temperatures in the primary cooling system of a nuclear power plant, suggest a specific kind of non-proportional multi-axial fatigue loading exists on the inner surface cooling structures. Stress controlled experiments mimicking these loading conditions were designed and run on an axial-torsional fatigue testing system. The cyclic loading observed in the finite element simulations consists of the superposition of proportional loading and a second, non-proportionality inducing component, the latter with a substantially lower amplitude and running at a higher cycling frequency. The amplitude of the non-proportionality inducing loading component is of a magnitude so small that the fatigue loading criteria, typically used in engineering standards for nuclear power plant safety, do not recognize the difference with the reference loading without this component. However, first experimental results show that the endurance limit of stainless steel of grade 316L is reduced by this additional loading, which we name non-proportional fatigue noise. The fact that the endurance limit is unexpectedly lowered is a non-conservative safety issue that challenges the currently existing criteria used to estimate the fatigue damage for this type of loading.

Effect of temperature during vital gluten adhesive preparation and application on shear-bond strength

If protein-based adhesives are to become a competitive bio-based alternative to synthetic adhesives, the preparation and application methods have to be considerable improved to reduce process time and thereby improve the economy of the adhesive system. The purpose of this study was to investigate the impact of the temperature during preparation and application on the shear-bond strength of an adhesive based on vital gluten for use in wood applications. Vital gluten was used in its natural form and mixed with water of different temperatures (preparation temperature 0 °C or 20 °C), and applied on beech veneer at different temperature (application temperature –10, 20, 60 and 100 °C). Tensile shear-bond strength samples were prepared and tested according to EN 205. The results showed that an increase in veneer temperature during application of the adhesive led to a decrease in the shear-bond strength, but that the preparation temperature of the adhesive had no influence on the strength.

The Science of Solubility: Using Reverse Engineering to Brew a Perfect Cup of Coffee

ABSTRACTThe Next Generation Science Standards call for the integration of science and engineering. Often, the introduction of engineering activities occurs after instruction in the science content. That is, engineering is used as a way for students to elaborate on science ideas that have already been explored. However, using only this sequence of instruction communicates a limited view of the relationship between science and engineering. In this article, we focus on the process of reverse engineering, and we provide a model 5E lesson in which we flip the typical science-to-engineering sequence and, instead, use principles of engineering design as a springboard from which to develop scientific concepts. Specifically, students use principles of engineering to deconstruct already engineered devices (i.e., different types of coffeemakers) in an effort to propose scientific explanations (i.e., factors affecting solubility) for the design features. These proposed explanations are then tested by isolating individual variables (e.g., solute size, temperature of solution) and testing the results. Students are provided whole coffee beans, grinders, water of different temperatures, timers, and apparatus for brewing samples of coffee and then test the effects of changing the variables by tasting, observing, or quantifying results of the individual samples.

Efficacy of Different Cooling Methods for Capture-Induced Hyperthermia in Antelope

The capture of wild animals is a stressful event which may cause a capture-induced hyperthermia, resulting in morbidity or mortality. We investigated whether various cooling techniques were effective at lowering the body temperature of hyperthermic animals. To achieve this, we implanted miniature temperature-sensitive data loggers into the abdomens of 12 blesbok (Damaliscus pygargus phillipsi ). Five animals were cooled by dousing with water of different temperatures (4°C, 17°C, 28°C) and fanning after dousing with 28°C water. Seven animals were cooled by ice-packs, a fine mist spray of 28°C water, intravenous (IV) infusion of one litre of 4°C saline solution or 28°C water-dousing. The body temperature after capture was significantly elevated to as high as 41°C to 42°C. Water-dousing interventions significantly decreased minimum body temperature but there was no difference in the minimum body temperature reached or the magnitude of cooling between the different water temperatures or by the addition of fanning. The ice-packs also lowered body temperature, whereas mist spraying did not. The use of ice packs and dousing with water between 4°C and 28°C were the most effective techniques to reduce capture-induced hyperthermia in blesbok. Water-dousing, when done appropriately, is the most practical and effective method to cool an animal with capture-induced hyperthermia.

Sudomotor activity and heat balance with serial cooling and heating of thermosensors in the esophagus and stomach

This study assessed heat balance parameters and characterized transient sweating responses on the forehead following graded changes in local temperature of the esophagus and stomach from ingesting water of different temperatures. Seven male participants cycled for 75‐min in a temperate environment while ingesting four 3.2 mL·kg−1 boluses of either 1.5°C, 10°C, 37°C or 50°C water, 5‐min before, and 15, 30 and 45‐min after the start of exercise at 50% VO2max. Whole‐body sweat loss (WBSL), rectal temperature (Tre), mean skin temperature (Tsk) and local sweat rate on the forehead (SRhead) were measured throughout. Evaporative heat loss from sweating (Esk), respiratory heat loss, dry heat losses and heat exchange with ingested water were subsequently calculated to estimate net body heat storage (S). Despite no differences in Tre or Tsk, the onset time for sudmotor activity on the forehead was significantly greater with declining fluid temperature (P&lt;0.05), and both mean SRhead throughout exercise and WBSL was significantly lower with 1.5°C compared to 50°C water ingestion (P=0.002). Values for S were significantly greater following 1.5°C water ingestion relative to 50°C (P=0.033), indicating a disproportionate reduction of thermoregulatory sweating, and therefore Esk, relative to the internal heat transfer with 1.5°C water. It is proposed that these data present evidence of independent thermoafferent processes arising from changes in local temperature of the esophagus and/or stomach.Funding for the study was provided by a NSERC discovery grant.

Surface modification of thin-film composite polyamide reverse osmosis membranes by coating N-isopropylacrylamide-co-acrylic acid copolymers for improved membrane properties

Commercial thin-film composite aromatic polyamide reverse osmosis membranes were modified by depositing N-isopropylacrylamide-co-acrylic acid copolymers (P(NIPAm-co-AAc)) on the membrane surface, and the modified membranes showed improved membrane properties. P(NIPAm-co-AAc) copolymers were synthesized by free radical copolymerization and their aqueous solutions of different concentrations were used to modify the polyamide membranes through in situ surface coating technique. The deposition of P(NIPAm-co-AAc) layer was shown to increase membrane surface hydrophilicity and surface charge at neutral pH, but offer additional resistance to water permeation. The effect of surface modification on membrane salt permeability was investigated through permeation tests with different salts under different pHs. The membrane modification was found to decrease the salt permeability of NaCl and Na2SO4 under neutral and alkaline conditions, and the decrease was significant for Na2SO4 that has divalent anions than for NaCl that has monovalent anions. The results of the fouling experiments with bovine serum albumin (BSA) aqueous solution and washing experiments with de-ionized water of different temperatures also revealed that the P(NIPAm-co-AAc) coating layer improved the fouling resistance to BSA and the cleaning efficiency. The phase transition of the coating layer under temperatures above its LCST would facilitate the removal of foulants located on the membrane surface.