Experimental investigation on the macro- and micromechanical properties of water-cooled granite at different high temperatures.

To investigate the damage mechanisms in granite's physical and mechanical properties after high-temperature water quenching, this study employed MTS815.04 for uniaxial compression tests on thermally treated specimens, with concurrent acoustic emission monitoring, and utilized nanoindentation for micromechanical analysis. The results show that with increasing temperature, granite's peak strength and elastic modulus decrease, with a sharp decline after 400-500 °C, corresponding to a significant increase in the internal damage, which can be detected by acoustic emission monitoring. Below 500 °C, macroscopic mechanical degradation is due to mineral thermophysical property differences, while above 500 °C, microcrack development is the main deterioration factor. The failure mode shifts from tensile to tensile-shear complex to shear failure, with transition points at 400 °C and 800 °C. The results of this study are of certain reference value for improving the efficiency of extracting thermal energy from dry-hot rocks and providing security guidance for the tunnel restoration process following fire damage.

Concentration levels of selected hormones in judokas and the extent of their changes during a special performance test at different ambient temperatures.

BACKGROUND: There is little scientific literature available on the diversity of physiological responses of judokas to anaerobic interval exercises in warm environments. Understanding the dynamics of changes in the concentration of selected hormones during a special endurance test at different ambient temperatures may have significant practical value, as it provides an opportunity for optimal programming and monitoring of the training process. So, the main aim of the research was to survey interval anaerobic exercises in different ambient temperatures on Concentration levels of selected hormones in judokas. METHODS: 15 judokas athletes (age: 20.65 ± 2.03 years; body height: 178.00 ± 6.31 cm;  body mass: 76.26 ± 12.57 kg; training experience: 12.1 ± 1.57 years) volunteered for the study. The judokas performed five sequences (each lasting 7.20 min) of pulsatile exercises on a cycle ergometer and hand ergometer in a thermoclimatic chamber at temperatures of 21 ± 0.5 °C and 31 ± 0.5 °C. The exercises were different from typical interval exercises, with varying times, upper and lower limb loads, and were followed by a 15-minute break after each sequence. Total duration of the experiment, including the five sequences of pulsating exercise and four 15-minute rest breaks between each exercise sequence, amounted to 96 min and 20 s. The workload was increased by 20 W for the lower limb tests and 12 W for the upper limb tests every 2 min. Biochemical measurements of testosterone (T), cortisol (C), growth hormone (HGH), adrenocorticotropic hormone (ACTH), follicle-stimulating hormone (FSH), adrenaline (E), noradrenaline (NE), and ß-endorphin (ß-end)were performed using the enzyme-linked immunosorbent assay (ELISA) method on blood samples taken before and after five series of pulsatile exercises, at 1, 24, and 48 h. RESULTS: Pulsatile exercise at ambient temperatures of 21 and 31 °C resulted in a decrease in body weight of the studied athletes (p < 0.05) and significantly reduced body volume and plasma volume after training (p < 0.05). The concentration of HGH, testosterone, cortisol and NE showed a statistically significant difference after the end of the series of pulsating exercises at both temperatures (p < 0.05) and did not significantly affect the concentration of ACTH, FSH and adrenaline concentration. CONCLUSIONS: An increase in the concentration of growth hormone, cortisol and NE was observed after doing the work at both 21 and 31 °C ambient temperature. Physical exertion in both ambient temperatures contributed to a statistically significant decrease in testosterone concentration. Based on the obtained research results, it can be concluded that physical activity in various thermal conditions of the external environment activates the hormonal response to varying degrees, with the direction of changes depending on the external thermal factor.

The Assessment of Withdrawal Interval for Enrofloxacin in Yellow Catfish (Pelteobagrus fulvidraco) after Multiple Oral Administrations at Disparate Temperatures.

The objective of the present study was to investigate the residue depletion of EF and CF in yellow catfish to estimate its WTs in plasma and tissues after multiple oral doses for 3 days at 20 mg/kg at 15, 20, and 25 °C. Samples were collected at pre-designed time points after oral doses. A validated method was performed to quantify EF and CF in plasma and tissues by high-performance liquid chromatography. Statistical differences were conducted using one-way ANOVA analysis. According to the maximum residue limit of China and Europe considering 95% percentile with 95% confidence, the WTs were estimated to be 44, 72, 66, 99, and 95 days at 15 °C; 32, 66, 65, 86, and 73 days at 20 °C; and 32, 61, 64, 55, and 59 days at 25 °C in the plasma, muscle and skin, gill, liver, and kidney, respectively. We found that increased temperature shortened the WTs in plasma and tissues. Therefore, this study can help the risk assessment of EF in aquatic products for human health at different temperatures to avoid residue violation.

Plasma and tissue kinetics of enrofloxacin and its metabolite, ciprofloxacin, in yellow catfish (Pelteobagrus fulvidraco) after a single oral administration at different temperatures.

The objective of this study was to examine the pharmacokinetic (PK) properties of enrofloxacin (EF) and its metabolite, ciprofloxacin (CF), in yellow catfish (Pelteobagrus fulvidraco) after a single oral dose of EF at 20 mg/kg at 20, 25, and 30 °C. Samples were collected at pre-designed time points and determined by high-performance liquid chromatography with a fluorescent detector. Results showed that most concentrations of EF and CF in plasma and tissues at the same time point at different temperatures were statistically significant. With the increase in temperature, the terminal half-life (T1/2λz) of EF and CF was first reduced from 20 to 25 °C but elevated from 25 to 30 °C in plasma, muscle + skin, gill, liver, and kidney, respectively. The area under the plasma concentration-time curves (AUClast) of EF were all decreased in plasma, muscle + skin, and gill except for that of EF in the liver and kidney. However, the AUClast and the apparent metabolic rate of CF were exhibited first elevated and then decreased trend. The apparent volume of distribution (Vz_F) of EF was first reduced from 20 to 25 °C but increased at 30 °C. The apparent total body clearance (CL_F) of EF was increased from 0.15 to 0.32 L/h·kg with the temperature elevation. These indicated that increased temperature markedly affected the PKs of EF and CF in yellow catfish. Through in-depth analysis, the EF dosage of 20 mg/kg is appropriate to use in yellow catfish at 20 and 25 °C but 30 °C.

The influence of extreme thermal stress on the physiological and psychological characteristics of young women who sporadically use the sauna: practical implications for the safe use of the sauna.

Background: Many individuals who use the sauna at a temperature of 120°C of higher are not aware of the negative consequences of extreme thermal stress. Despite extensive research into sauna use, the impact of extreme thermal stress on the physiological and psychological characteristics of sauna users have not been examined to date. Aim: The aim was to determine the effect of 20 min sauna sessions with a temperature of 80°C and 120°C on the physiological and psychological characteristics of women who sporadically visit the sauna. Methods: The study was conducted on 22 full-time female university students. Physical activity (PA) levels were evaluated with the Polish short version of the International Physical Activity Questionnaire (IPAQ). Anthropometric characteristics were measured before the first sauna session by the InBody270 body composition analyzer. Physiological parameters, including heart, energy expenditure, physical effort, and blood pressure (systolic blood pressure - SBP, and diastolic blood pressure - DBP), were assessed indirectly using Polar V800 heart rate monitors and the Omron M6 Comfort blood pressure monitor. The participants' wellbeing was assessed with the Profile of Mood States (POMS) questionnaire. The presence of significant correlations between heat exhaustion and heat stress variables and syncope during the second sauna session was examined with the use of classification and regression trees (CRT) and the cross-validation technique. Results: Twenty-minute sauna sessions with a temperature of 80°C and 120°C induced a significant (p < 0.001) decrease in the values of SBP (excluding the temperature of 120°C), DBP, and body mass, as well as a significant increase in HR and forehead temperature. Exposure to a temperature of 80°C led to a significant (p < 0.001) increase in vigor with a simultaneous decrease in tension, depression, anger, fatigue, and confusion. In turn, sauna bathing at a temperature of 120°C had an opposite effect on the above mood parameters. Vomiting and confusion were the main predictors of syncope that occurred in some of the surveyed women. Conclusion: Excessive air temperature can induce symptoms characteristic of heat exhaustion and heat stress nausea, heavy sweating, fast weak or strong HR, high body temperature, and confusion. Therefore, sauna bathing at a temperature of 80°C can be recommended to women who sporadically use the sauna, whereas exposure to a temperature of 120°C is not advised in this group of sauna users. The present findings provide highly valuable inputs for managing wellness and SPA centers.

Effect of coating on flavor metabolism of fish under different storage temperatures.

Two edible coatings (gelatin coating and ginger essential oil-gelatin coating) were prepared to maintain the flavor quality of fish fillets at two storage temperatures (4 °C and 25 °C). The effects of coating on fish fillets were evaluated by detecting the physical properties, microstructure, microbial properties, volatile flavor and taste flavor of fish. In the same coating method, fish fillets stored at 4 °C showed better effect than that at 25 °C on maintain water content, color and texture, however, fish fillets stored at 25 °C were closer to fresh fish in volatile flavor and taste flavor than that at 4 °C; whatever the storage temperature, coating could slow down the growth of fish microorganisms, maintain water content, color, texture, volatile flavor and taste flavor of fish fillets; GGC exhibited better effect on maintain flavor quality than GC.

Temperature-Dependent Antimicrobial Activity of Menhaden Fish Oil In Vitro and on Pet Food Kibbles against Salmonella.

ABSTRACT: Fish oil inclusion into a dry pet food provides a source of long-chain omega-3 fatty acids. Polyunsaturated fatty acids in fish oil have antibacterial activity against various foodborne pathogens, such as Salmonella and pathogenic Escherichia coli. The purpose of this study was to determine the effect of temperature applied to dry pet food kibbles on the antimicrobial activity of menhaden fish oil against Salmonella spp. Sterile menhaden oil was inoculated with ∼8 log of a Salmonella cocktail (∼3% moisture; Salmonella Enteritidis, Salmonella Heidelberg, and Salmonella Typhimurium) and incubated at 25, 37, and 45°C. Microbiological evaluation of the water phase was done after 2 h on tryptic soy agar. Sterile kibbles were coated with fish oil (7.0%, w/w). Canola oil coating was kept as a control. One hour after coating, the kibbles were inoculated with ∼9 log of Salmonella and incubated at the respective temperature. The microbiological evaluation was conducted at 0, 2, 6, 12, and 24 h. The oil phase of the fish oil system was negative for Salmonella after 2 h of incubation and confirmed by enrichment and PCR. From the water phase, 8.1 and 7.3 log were recovered at 25 and 37°C, respectively, and no Salmonella was detected at 45°C. On the kibble, menhaden oil had higher antimicrobial (P ≤ 0.05) activity after 12 h at 25°C and throughout the experiment at 37°C. At 45°C, the fish oil had a superior antimicrobial activity against the Salmonella cocktail after 2 h. When the fish oil alone was compared at different temperatures, a higher antimicrobial activity was observed at 37 and 45°C across all time points. The results indicate antimicrobial activity of menhaden oil increases with temperature. This is an important finding to the pet food industry: a higher fat holding temperature (∼45°C) and the application process may help mitigate Salmonella on extruded kibbles.

[Impact of different temperatures and ambient PM2.5 on the cytotoxicity and cytophagocytic function of alveolar macrophages of rat].

OBJECTIVE: To investigate the interactive effects of different temperatures and ambient PM2.5 on the rat alveolar macrophages. METHODS: The rat alveolar macrophages were collected. The cells were exposed in vitro to 18℃, 24℃, 30℃, 37℃ and 43℃ with PM2.5 at the concentrations of 100 µg/ml, 50 µg/ml, 25 µg/ml and 0 µg/ml respectively. The cells were cultured in the different cases for 8 hours, then cytotoxicity was assessed by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide(MTT)reduction assay and phagocytosis function of macrophages was assessed by neutral red absorption test. RESULTS: The relative survival rate and the cytophagocytic function of alveolar macrophages of rats among the different concentration groups decreased significantly (P<0.05) compared with the blank control group. Both were dose-dependent. The 37℃ group had the highest level of relative survival rate and the cytophagocytic function compared with other different temperatures groups. Interactive effect of different temperatures and ambient PM2.5 was not observed. But the lower temperature and the higher PM2.5 concentration group had stronger toxicity to alveolar macrophages. CONCLUSIONS: The results suggested that different temperatures and ambient PM2.5 have cytotoxicity on alveolar macrophages,injuring the phagocytosis. The two factors had some interaction.

The Hybrid Strategy of Thermoactinospora rubra YIM 77501T for Utilizing Cellulose as a Carbon Source at Different Temperatures.

Thermoactinospora rubra YIM 77501T is an aerobic, Gram-positive, spore-forming and cellulose degrading thermophilic actinomycete isolated from a sandy soil sample of a volcano. Its growth temperature range is 28-60°C. The genomic sequence of this strain revealed that there are 27 cellulase genes belonging to six glycoside hydrolase families. To understand the strategy that this strain uses to utilize carbon sources such as cellulose at different temperatures, comparative transcriptomics analysis of T. rubra YIM 77501T was performed by growing it with cellulose (CMC) and without cellulose (replaced with glucose) at 30, 40, and 50°C, respectively. Transcriptomic analyses showed four cellulase genes (TrBG2, TrBG3, TrBG4, and ThrCel6B) were up-regulated at 30, 40, and 50°C. The rate of gene expression of TrBG2, TrBG3, TrBG4, and ThrCel6B were 50°C > 30°C > 40°C. One cellulase gene (TrBG1) and two cellulase genes (TrBG5 and ThrCel6A) were up-regulated only at 30 and 50°C, respectively. These up-regulated cellulase genes were cloned and expressed in Escherichia coli. The enzymatic properties of up-regulated cellulases showed a variety of responses to temperature. Special up-regulated cellulases TrBG1 and ThrCel6A displayed temperature acclimation for each growth condition. These expression patterns revealed that a hybrid strategy was used by T. rubra to utilize carbon sources at different temperatures. This study provides genomic, transcriptomics, and experimental data useful for understanding how microorganisms respond to environmental changes and their application in enhancing cellulose hydrolysis for animal feed and bioenergy production.

Temperature selection of intravesical sodium hyaluronate in the treatment of interstitial cystitis / 中国临床药理学与治疗学

AIM: To investigate the efficacy of bladder infusion of sodium hyaluronate (HA) in the treatment of interstitial cystitis (IC) at different temperatures. METHODS: Forty patients with IC admitted in our hospital from March 2018 to April 2019 were simply randomized and divided into two groups for prospective study, with 20 patients in each group. The temperature of perfusion fluid in normal temperature group was 37 ℃, and the temperature of perfusion fluid in high temperature group was 43 ℃. Compared the two groups before treatment, one month after treatment, and three months after treatment of interstitial cystitis problem score (ICPI), interstitial bladder symptoms score (ICSI), pre-veeing pain visual analogue score (VAS), and anxiety self-assessment scale (SAS), depression self-assessment scale (SDS), quality of life score (QOL), daily urination times, maximum bladder volume, bladder mast cell count, and immune factors [interleukin (IL)-6, IL-10] expression. RESULTS:The ICPI, ICSI, VAS, SAS, and SDS scores of the hyperthermia group were lower than those of the normal temperature group after one month and three months of treatment, and the QOL scores were higher than those of the normal temperature group after three months of treatment (P0.05). CONCLUSION:Compared with 37 ℃, intravesical instillation of HA in the treatment of IC can effectively relieve the clinical symptoms and signs of patients when the perfusion fluid is at a temperature of 43 ℃, and it improves the maximum bladder capacity and anxiety and depression, improves the quality of life of patients, which is safe and reliable. The mechanism may be related to the regulation of large cell, IL-6, IL-10 of bladder mucosa.

Study on assessment of proximate composition and meat quality of fresh and stored Clarias gariepinus and Cyprinus carpio / Estudo da avaliação da composição centesimal e da qualidade da carne de Clarias gariepinus e Cyprinus carpio

Abstract The organoleptic evaluation and proximate analysis of Clarias gariepinus and Cyprinus carpio were determined in fresh fish and when refrigerated at two different temperatures (-21 °C and 4 °C) for a period of six weeks. A panel of twelve trained judges evaluated the color (live), texture, softness and flavor of fish meat after two minutes' steam cooking. Average score revealed a general decline in organoleptic properties such as color, texture, freshness, and taste of C. gariepinus and C. carpio stored at two temperatures compared to the fresh fish. Proximate analysis revealed a more decrease in crude protein and lipid contents and increase in ash content in C. gariepinus and C. carpio at the two storage temperatures compared to the fresh fish muscle. Moisture content decreased in the fish muscle samples of both the fish species stored at -21 °C but increased in the 4 °C stored samples. pH of fish was found to increase in the two stored temperatures. There were significant differences (P<0.05) in the organoleptic and proximate composition of the ice stored and fresh C. gariepinus and C. carpio, the same temperature and between the two different temperatures. The quality of fish muscle stored at 4 °C deteriorated faster than that of the -21 °C. Thus, storage temperature and duration have adverse effects on the nutritional quality of fish meat.

Resumo A avaliação organoléptica e a análise aproximada de Clarias gariepinus e Cyprinus carpio foram determinadas em peixe fresco e refrigerado a duas temperaturas diferentes (-21 °C e 4 °C) por um período de seis semanas. Um painel de doze juízes treinados avaliou a cor (ao vivo), textura, maciez e sabor da carne de peixe após dois minutos de cozimento a vapor. O escore médio revelou um declínio geral nas propriedades organolépticas, como cor, textura, frescor e sabor de C. gariepinus e C. carpio armazenados a duas temperaturas em comparação com o peixe fresco. A análise imediata revelou uma maior diminuição nos teores de proteína bruta e lipídios e aumento no teor de cinzas em C. gariepinus e C. carpio nas duas temperaturas de armazenamento em comparação com o músculo do peixe fresco. O teor de umidade diminuiu nas amostras de músculo de peixe de ambas as espécies de peixes armazenadas a -21 °C, mas aumentou nas amostras armazenadas a 4 °C. O pH dos peixes aumentou nas duas temperaturas armazenadas. Houve diferenças significativas (P <0,05) na composição organoléptica e próxima do gelo armazenado e fresco C. gariepinus e C. carpio, a mesma temperatura e entre as duas temperaturas diferentes. A qualidade do músculo do peixe armazenado a 4 °C deteriorou-se mais rapidamente do que a temperatura de -21 °C. Assim, a temperatura e duração do armazenamento têm efeitos adversos na qualidade nutricional da carne de peixe.

Microbial contribution to spoilage of African breadfruit (Artocarpus communis, Forst) during storage.

The contributions of microorganisms in the deterioration of African breadfruit during storage were investigated in this study. Matured fruits of the seedless variety of the African breadfruit (Artocarpus communis, Forst) were stored under different temperature conditions and morphological changes observed at 24-h intervals for 120 h. Spoilage of breadfruit was observed after 72 h with microbial growth. Although all the fruits in the different media deteriorated by the 72nd hour (this was revealed in morphology and confirmed by the proximate analysis which showed an increase in %crude protein in all the stored fruits), microbial growth was observed only in those fruits stored at room temperature and in water, and there was no significant microbial growth in fruits stored in refrigerator, freezer, and vinegar. A higher rate of deterioration (i.e., higher %crude protein) was observed in morphology of fruits which had microbial growth during storage (i.e., those stored in the room, under water, and refrigerator) than in those stored fruits with no significant microbial growth. The difference between the %crude protein in fruits where there is microbial growth and that of the fruits where there is no microbial growth (i.e., freezer and vinegar) proved to be significant (P ≤ 0.05). The study thus reveals that microorganisms play a substantial role in the spoilage of African breadfruit. A strain of the Aspergillus sp., two strains of the Penicillium sp., and a strain of the Molinia sp. were isolated as fungal spoilage organisms. Bacillus sp. and Pseudomonas sp. strains were isolated as bacteria spoilage organisms.

Study on assessment of proximate composition and meat quality of fresh and stored Clarias gariepinus and Cyprinus carpio

Abstract The organoleptic evaluation and proximate analysis of Clarias gariepinus and Cyprinus carpio were determined in fresh fish and when refrigerated at two different temperatures (-21 °C and 4 °C) for a period of six weeks. A panel of twelve trained judges evaluated the color (live), texture, softness and flavor of fish meat after two minutes steam cooking. Average score revealed a general decline in organoleptic properties such as color, texture, freshness, and taste of C. gariepinus and C. carpio stored at two temperatures compared to the fresh fish. Proximate analysis revealed a more decrease in crude protein and lipid contents and increase in ash content in C. gariepinus and C. carpio at the two storage temperatures compared to the fresh fish muscle. Moisture content decreased in the fish muscle samples of both the fish species stored at -21 °C but increased in the 4 °C stored samples. pH of fish was found to increase in the two stored temperatures. There were significant differences (P 0.05) in the organoleptic and proximate composition of the ice stored and fresh C. gariepinus and C. carpio, the same temperature and between the two different temperatures. The quality of fish muscle stored at 4 °C deteriorated faster than that of the -21 °C. Thus, storage temperature and duration have adverse effects on the nutritional quality of fish meat.

Resumo A avaliação organoléptica e a análise aproximada de Clarias gariepinus e Cyprinus carpio foram determinadas em peixe fresco e refrigerado a duas temperaturas diferentes (-21 °C e 4 °C) por um período de seis semanas. Um painel de doze juízes treinados avaliou a cor (ao vivo), textura, maciez e sabor da carne de peixe após dois minutos de cozimento a vapor. O escore médio revelou um declínio geral nas propriedades organolépticas, como cor, textura, frescor e sabor de C. gariepinus e C. carpio armazenados a duas temperaturas em comparação com o peixe fresco. A análise imediata revelou uma maior diminuição nos teores de proteína bruta e lipídios e aumento no teor de cinzas em C. gariepinus e C. carpio nas duas temperaturas de armazenamento em comparação com o músculo do peixe fresco. O teor de umidade diminuiu nas amostras de músculo de peixe de ambas as espécies de peixes armazenadas a -21 °C, mas aumentou nas amostras armazenadas a 4 °C. O pH dos peixes aumentou nas duas temperaturas armazenadas. Houve diferenças significativas (P 0,05) na composição organoléptica e próxima do gelo armazenado e fresco C. gariepinus e C. carpio, a mesma temperatura e entre as duas temperaturas diferentes. A qualidade do músculo do peixe armazenado a 4 °C deteriorou-se mais rapidamente do que a temperatura de -21 °C. Assim, a temperatura e duração do armazenamento têm efeitos adversos na qualidade nutricional da carne de peixe.