Journal articles on the topic 'Deep-water immersion'
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WANG, QIAN, SHIBIAO WEI, GUANGHUI YUAN, and XIAO-CONG YUAN. "WATER-IMMERSION DEEP-SUBWAVELENGTH SURFACE PLASMON VIRTUAL PROBES." Journal of Molecular and Engineering Materials 02, no. 02 (June 2014): 1440010. http://dx.doi.org/10.1142/s2251237314400103.
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In this paper, we report the observation of surface plasmon virtual probes in water by using near-field scanning optical microscope. The full-width half-maximum of the probe is as small as λ0/5.5. Such deep-subwavelength sized plasmonic virtual probe may lead to many potential applications, such as super-resolution fluorescence optical imaging and optical manipulation.
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Romet, T. T. "Mechanism of afterdrop after cold water immersion." Journal of Applied Physiology 65, no. 4 (October 1, 1988): 1535–38. http://dx.doi.org/10.1152/jappl.1988.65.4.1535.
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It was hypothesized that if afterdrop is a purely conductive phenomenon, the afterdrop during rewarming should proceed initially at a rate equal to the rate of cooling. Eight male subjects were cooled on three occasions in 22 degrees C water and rewarmed once by each of three procedures: spontaneous shivering, inhalation of heated (45 degrees C) and humidified air, and immersion up to the neck in 40 degrees C water. Deep body temperature was recorded at three sites: esophagus, auditory canal, and rectum. During spontaneous and inhalation rewarming, there were no significant differences between the cooling (final 30 min) and afterdrop (initial 10 min) rates as calculated for each deep body temperature site, thus supporting the hypothesis. During rapid rewarming, the afterdrop rate was significantly greater than during the preceding cooling, suggesting a convective component contributing to the increased rate of fall. The rapid reversal of the afterdrop also indicates that a convective component contributes to the rewarming process as well.
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Castleberry, Todd, Vic BenEzra, Sarah Deemer, Tara Niemann, and Janie Foreman. "The Effects of Deep Water Running and Cold Water Immersion on Muscle Soreness." Medicine & Science in Sports & Exercise 47 (May 2015): 357. http://dx.doi.org/10.1249/01.mss.0000477395.02083.8a.
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Zheng, Jing, Junqiao Zhang, Lu Tan, Debing Li, Liangliang Huang, Qi Wang, and Yingchun Liu. "Effects of Aspect Ratio on Water Immersion into Deep Silica Nanoholes." Langmuir 32, no. 34 (August 17, 2016): 8759–66. http://dx.doi.org/10.1021/acs.langmuir.6b01575.
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Greenwood, Austin, and Cordial Gillette. "Effect of Cold Water Immersion on Metabolic Rate in Humans." International Journal of Kinesiology and Sports Science 5, no. 2 (April 30, 2017): 1. http://dx.doi.org/10.7575/aiac.ijkss.v.5n.2p.1.
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Background: Cold water immersion is a widely used form of cryotherapy in the active population despite the limited knowledge on its physiological effects. From an injury standpoint, reducing metabolic rate is advantageous to prevent secondary injury. In contrast, increased metabolism can be beneficial in ridding the body of unwanted metabolites. This study looked to determine the effect of cold water immersion on metabolic rate. Understanding this phenomenon will help determine appropriate clinical applications of cold water immersion and lead to a better understanding of cryotherapy in general. This study looked to determine the effect of cryotherapy in the form of waist deep cold water immersion at 9° C on metabolic rate. Methods: 10 participants from a university student population volunteered and completed a 15-minute treatment of waist deep cold water (9° C) immersion. Metabolic rate measurements were taken using a Jaeger Oxycon Mobile Unit for 5 minutes prior to treatment, 15 minutes of treatment, and 5 minutes post treatment for a total of 25 minutes. Statistical analysis was completed using a one way repeated measures ANOVA test to compare treatment intervals to baseline intervals. Results: Cold water immersion resulted in elevated metabolic rates for 8 of 10 participants during the first 5 minutes of treatment and for 6 of 10 in the 5 minute post treatment (p < 0.05). A second statistical analysis excluding the first 30 second data point in the 5-10 and 20-25 minute treatments was used to account for movement in and out of the whirlpool. The second analysis showed the same results as the first with the exception of one participant who no longer displayed a statistically significant change in the 20-25 minute interval. Conclusion: These results indicate that cold water immersion should not be used as a measure of reducing secondary injury because of its potential to increase metabolic rate, but instead may have potential benefits in exercise recovery.
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Bierens, Joost J. L. M., Philippe Lunetta, Mike Tipton, and David S. Warner. "Physiology Of Drowning: A Review." Physiology 31, no. 2 (March 2016): 147–66. http://dx.doi.org/10.1152/physiol.00002.2015.
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Drowning physiology relates to two different events: immersion (upper airway above water) and submersion (upper airway under water). Immersion involves integrated cardiorespiratory responses to skin and deep body temperature, including cold shock, physical incapacitation, and hypovolemia, as precursors of collapse and submersion. The physiology of submersion includes fear of drowning, diving response, autonomic conflict, upper airway reflexes, water aspiration and swallowing, emesis, and electrolyte disorders. Submersion outcome is determined by cardiac, pulmonary, and neurological injury. Knowledge of drowning physiology is scarce. Better understanding may identify methods to improve survival, particularly related to hot-water immersion, cold shock, cold-induced physical incapacitation, and fear of drowning.
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Forrest, George, and Kurt Rosen. "Ultrasound Treatments in Degassed Water." Journal of Sport Rehabilitation 1, no. 4 (November 1992): 284–89. http://dx.doi.org/10.1123/jsr.1.4.284.
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Ultrasound is a commonly used modality of deep heating. Two techniques of application have been recommended: a technique in which the applicator head is applied directly to the subject and an immersion technique, The purpose of this study was to determine whether ultrasound treatments using the immersion technique in degassed water are as effective as ultrasound treatments using the direct technique of application in raising the temperature of periarticular structures into the therapeutic range. The limbs of a pig were treated with the direct and immersion techniques of application. Temperatures of the skin surface and of the extensor tendons of the ankle were taken before and after both methods of application. Treatments with the applicator head in direct contact with the limb of the subject were the more effective form of heating.
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Iwamoto, J., S. Sagawa, F. Tajima, K. Miki, and K. Shiraki. "Critical water temperature during water immersion at various atmospheric pressures." Journal of Applied Physiology 64, no. 6 (June 1, 1988): 2444–48. http://dx.doi.org/10.1152/jappl.1988.64.6.2444.
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The present work was undertaken to determine the effect of atmospheric pressure [ranging from a high altitude of 4,300 m above sea level or 0.6 atmospheres absolute (ATA) to depths of 10 m deep or 2 ATA] on the critical water temperature (Tcw), defined as the lowest water temperature a subject can tolerate at rest for 2 h without shivering, of the unprotected subject during water immersion. Nine healthy males wearing only shorts were subjected to immersion to the neck in water at 0.6, 1, and 2 ATA while resting for 2 h. Continuous measurements included esophageal (Tes) and skin (Tsk) temperatures, direct heat loss from the skin (Htissue), and insulation of the tissue (Itissue). The Tcw was significantly higher at 0.6 ATA than 1 and 2 ATA: however, Tcw at 1 ATA was identical to that at 2 ATA. The metabolic heat production remained unchanged among the pressures. During the 2-h immersion in Tcw, Tes was identical among all atmospheric pressures: however, Tsk was significantly higher (P less than 0.05) at 0.6 ATA and was identical between 1 and 2 ATA. The overall mean Itissue was near maximal during immersion in Tcw in each pressure, and no difference was detected among the pressures. However, Itissue at the acral extremities (arm, hand, and foot) decreased significantly at 0.6 ATA, and subsequently heat loss from these parts was increased, which elevated an extremity-to-trunk heat loss ratio to 1.4 at 0.6 ATA from 1.1 at 1 and 2 ATA.
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Rodríguez, L., A. Benavides-Moran, and S. Laín. "Three-Bladed Horizontal Axis Water Turbine Simulations with Free Surface Effects." International Journal of Applied Mechanics and Engineering 26, no. 3 (August 26, 2021): 187–97. http://dx.doi.org/10.2478/ijame-2021-0044.
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Abstract The water level above a hydrokinetic turbine is likely to vary throughout the season and even along the day. In this work, the influence of the free surface on the performance of a three bladed horizontal-axis turbine is explored by means of a three-dimensional, transient, two-phase flow computational model implemented in the commercial CFD software ANSYS Fluent 19.0. The k – ω SST Transition turbulence model coupled with the Volume of Fluid (VOF) method is used to track the air-water interface. The rotor diameter is D = 0 8m. Two operating conditions are analyzed: deep tip immersion (0.55D) and shallow tip immersion (0.19D). Three tip speed ratios are evaluated for each immersion. Simulation results show a good agreement with experimental data reported in the literature, although the computed torque and thrust coefficients are slightly underestimated. Details of the free surface dynamics, the flow past the turbine and the wake near the rotor are also discussed.
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Jing, Wei, Xu Wang, Pengwei Hao, Laiwang Jing, and Weipei Xue. "Instability Mechanism and Key Control Technology of Deep Soft Rock Roadway under Long-Term Water Immersion." Advances in Civil Engineering 2021 (January 6, 2021): 1–13. http://dx.doi.org/10.1155/2021/6670379.
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More and more attention has been paid to the supporting problem of deep soft rock roadway floor with long-term water immersion in recent years. However, the existing soft rock roadway support technology rarely takes into account the influence of the immersion softening phenomenon of the roadway floor and the self-supporting structure characteristics of the surrounding rock on the stability of the surrounding rock at the same time, and the influence of the creep characteristics of rock on the deformation zone of the surrounding rock requires further research on the nature and division of the self-supporting structure of the surrounding rock. In response to the issues mentioned, based on the loading and unloading properties of the surrounding rock of the soft rock roadway, a new concept of the internal and external self-bearing structure was proposed. The fact of water-immersed mudstone softening in the soft rock roadway floor was revealed through the field practice, and the shape of the internal and external bearing structure was determined based on the in situ monitoring results. Then, the instability mechanism of the internal and external self-bearing structure of the surrounding rock was analyzed, the position of the critical control point was calculated, and the key control technology based on the method of controlling floor heave by using double-row anchor cables to control the deformation of the roadway sides was put forward. Finally, the field industrial test showed that this support technology can effectively control the deformation and failure of soft rock roadway in the case of water immersion on the floor. This work can provide a technical reference for similar roadway support designs.
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Jing, Wei, Xu Wang, Pengwei Hao, Laiwang Jing, and Weipei Xue. "Instability Mechanism and Key Control Technology of Deep Soft Rock Roadway under Long-Term Water Immersion." Advances in Civil Engineering 2021 (January 6, 2021): 1–13. http://dx.doi.org/10.1155/2021/6670379.
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More and more attention has been paid to the supporting problem of deep soft rock roadway floor with long-term water immersion in recent years. However, the existing soft rock roadway support technology rarely takes into account the influence of the immersion softening phenomenon of the roadway floor and the self-supporting structure characteristics of the surrounding rock on the stability of the surrounding rock at the same time, and the influence of the creep characteristics of rock on the deformation zone of the surrounding rock requires further research on the nature and division of the self-supporting structure of the surrounding rock. In response to the issues mentioned, based on the loading and unloading properties of the surrounding rock of the soft rock roadway, a new concept of the internal and external self-bearing structure was proposed. The fact of water-immersed mudstone softening in the soft rock roadway floor was revealed through the field practice, and the shape of the internal and external bearing structure was determined based on the in situ monitoring results. Then, the instability mechanism of the internal and external self-bearing structure of the surrounding rock was analyzed, the position of the critical control point was calculated, and the key control technology based on the method of controlling floor heave by using double-row anchor cables to control the deformation of the roadway sides was put forward. Finally, the field industrial test showed that this support technology can effectively control the deformation and failure of soft rock roadway in the case of water immersion on the floor. This work can provide a technical reference for similar roadway support designs.
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Mawhinney, Chris, Ilkka Heinonen, David A. Low, Chunlei Han, Helen Jones, Kari K. Kalliokoski, Anna Kirjavainen, et al. "Changes in quadriceps femoris muscle perfusion following different degrees of cold-water immersion." Journal of Applied Physiology 128, no. 5 (May 1, 2020): 1392–401. http://dx.doi.org/10.1152/japplphysiol.00833.2019.
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Using positron emission tomography, we report for the first time muscle perfusion heterogeneity in the quadriceps femoris in response to different degrees of cold-water immersion (CWI). Noxious CWI temperatures (8°C) increase perfusion in the deep quadriceps muscle, whereas superficial quadriceps muscle perfusion is reduced in cooler (15°C) water. Therefore, these data have important implications for the selection of CWI approaches used in the treatment of soft tissue injury, while also increasing our understanding of the potential mechanisms underpinning CWI.
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Meyer, Katharina, and Marie-Claude Leblanc. "Aquatic therapies in patients with compromised left ventricular function and heart failure." Clinical & Investigative Medicine 31, no. 2 (April 1, 2008): 90. http://dx.doi.org/10.25011/cim.v31i2.3369.
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With water immersion, gravity is partly eliminated, and the water exerts a pressure on the body surface. Consequently there is a blood volume shift from the periphery to the central circulation, resulting in marked volume loading of the thorax and heart. This paper presents a selection of published literature on water immersion, balneotherapy, aqua exercises, and swimming, in patients with left ventricular dysfunction (LVD) and/or stable chronic heart failure (CHF). Based on exploratory studies, central hemodynamic and neurohumoral responses of aquatic therapies will be illustrated. Major findings are: 1. In LVD and CHF, a positive effect of therapeutic warm-water tub bathing has been observed, which is assumed to be from afterload reduction due to peripheral vasodilatation caused by the warm water. 2. In coronary patients with LVD, at low-level water cycling the heart is working more efficiently than at lowlevel cycling outside of water. 3. In patients with previous extensive myocardial infarction, upright immersion to the neck resulted in temporary pathological increases in mean pulmonary artery pressure (mPAP) and mean pulmonary capillary pressures (mPCP). 4. Additionally, during slow swimming (20-25m/min) the mPAP and/or PCP were higher than during supine cycling outside water at a 100W load. 5. In CHF patients, neck- deep immersion resulted in a decrease or no change in stroke volume. 6. Although patients are hemodynamically compromised, they usually maintain a feeling of well-being during aquatic therapy. Based on these findings, clinical indications for aquatic therapies are proposed and ideas are presented to provoke further research.
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Wang, Hong Song, Lei Li, Zi Wei Ni, and Qian Tian. "Water Absorption and Resistance to Chloride Ion Performance of Concrete Waterproof Silicone Material." Applied Mechanics and Materials 357-360 (August 2013): 809–12. http://dx.doi.org/10.4028/www.scientific.net/amm.357-360.809.
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Water, chloride ion, deicing salt and freeze-thaw cycle are the greatest enemy of the concrete, leading to concrete corrosion damage, the concrete building protection materials is utilized widely in the hydraulic and bridge engineering. Using the silane materials to an immersion treatment can effectively block the invasion of harmful substances,the results showed that the deep penetration of silicone material formed a hydrophobic layer and provided an effective protection against water corrosion and chloride ingress. Such an organic silicon material is no evaporation of solvent, friendly to the environment, so is considered the most suitable for concrete protection.
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Mendes de Barros Correia, José Renato, Erandy Gomes da Silva, Carlos Augusto França Schettini, José Carlos Pacheco dos Santos, Tiago Hilário Pedrosa Campello, and Maria Elisabeth De Araújo. "USING AGGREGATING DEVICES TO SAMPLE FISH RECRUITS AROUND DEEP SHIPWRECKS: EXPERIMENTS AND SUGGESTIONS." Arquivos de Ciências do Mar 53, no. 1 (August 31, 2020): 63–81. http://dx.doi.org/10.32360/acmar.v53i1.42376.
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Fish aggregating devices (FAD) are an ancient fishery technique that benefits from the gregarious behavior of many species. They represent alternatives to usual census approach to study fish recruits. Based on this, we test two FAD models built for fish recruitment research, Standard monitoring unit for the recruitment of reef fishes (SMURF) and Artificial Reef Mooring (ARM) moored for the first time close to deep shipwrecks inBrazil Northeastern coast. We compared fish recruits’ abundance sampled by both models at two depths, bottom and mid-water (6 meters from the bottom). SMURFs sampled seven times more fish recruits than ARM with no difference between depth. We discovered that SMURFs mooring tilted 24º in mean with local marine currents. A long-term study with SMURFs tested immersion time influence in recruit’s sampling, and explored recruit’s abundance and standard length at two depth from the bottom. Increasing immersion timefrom 14-28 days did not influence recruit’s abundance. Bottom and Mid-water SMURFs sampled equal recruit’s number and fish sizes were significantly larger at the bottom. FADs, specially SMURFs, showed good tool to sample fish recruits in deeper shipwrecks,however standardization of FAD deployment is indicated to maximize work time and security in unstable sea conditions.
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Kutcherov, V. G., K. S. Ivanov, and A. Yu Serovaiskii. "Deep hydrocarbon cycle." LITHOSPHERE (Russia) 21, no. 3 (July 8, 2021): 289–305. http://dx.doi.org/10.24930/1681-9004-2021-21-3-289-305.
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Research subject. Experimental modelling of the transformation of complex hydrocarbon systems under extreme thermobaric conditions was carried out. The results obtained were compared with geological observations in the Urals, Kamchatka and other regions.Material and methods. The materials for the research were a model hydrocarbon system similar in composition to natural gas condensate and a system consisting of a mixture of saturated hydrocarbons and various iron-containing minerals enriched in 57Fe. Two types of high-pressure equipment were used: a diamond anvils cell and a Toroid-type high-pressure chamber. The experiments were carried out at pressures up to 8.8 GPa in the temperature range 593–1600 K.Results. According to the obtained results, hydrocarbon systems submerged in a subduction slab can maintain their stability down to a depth of 50 km. Upon further immersion, during contact of the hydrocarbon fluid with the surrounding iron-bearing minerals, iron hydrides and carbides are formed. When iron carbides react with water under the thermobaric conditions of the asthenosphere, a water-hydrocarbon fluid is formed. Geological observations, such as methane finds in olivines from ultramafic rocks unaffected by serpentinization, the presence of polycyclic aromatic and heavy saturated hydrocarbons in ophiolite allochthons and ultramafic rocks squeezed out from the paleo-subduction zone of the Urals, are in good agreement with the experimental data.Conclusion. The obtained experimental results and presented geological observations made it possible to propose a concept of deep hydrocarbon cycle. Upon the contact of hydrocarbon systems immersed in a subduction slab with iron-bearing minerals, iron hydrides and carbides are formed. Iron carbides carried in the asthenosphere by convective flows can react with hydrogen contained in the hydroxyl group of some minerals or with water present in the asthenosphere and form a water-hydrocarbon fluid. The mantle fluid can migrate along deep faults into the Earth’s crust and form multilayer oil and gas deposits in rocks of any lithological composition, genesis and age. In addition to iron carbide coming from the subduction slab, the asthenosphere contains other carbon donors. These donors can serve as a source of deep hydrocarbons, also participating in the deep hydrocarbon cycle, being an additional recharge of the total upward flow of a water-hydrocarbon fluid. The described deep hydrocarbon cycle appears to be part of a more general deep carbon cycle.
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Lee, Jong-Sun, Ji-Won Han, Munyhung Jung, Kwang-Won Lee, and Myung-Sub Chung. "Effects of Thawing and Frying Methods on the Formation of Acrylamide and Polycyclic Aromatic Hydrocarbons in Chicken Meat." Foods 9, no. 5 (May 4, 2020): 573. http://dx.doi.org/10.3390/foods9050573.
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Air frying is commonly used as a substitute for deep-fat frying. However, few studies have examined the effect of air frying on the formation of potential carcinogens in foodstuffs. This study aimed to investigate the formation of acrylamide and four types of polycyclic aromatic hydrocarbons (PAHs) in air-fried and deep-fat-fried chicken breasts, thighs, and wings thawed using different methods, i.e., by using a microwave or a refrigerator, or by water immersion. The acrylamide and PAHs were analyzed by high-performance liquid chromatography–tandem mass spectrometry (HPLC-MS/MS) and gas chromatography–mass spectrometry (GC-MS), respectively. Deep-fat-fried chicken meat had higher acrylamide (n.d.–6.19 μg/kg) and total PAH (2.64–3.17 μg/kg) air-fried chicken meat (n.d.–3.49 μg/kg and 1.96–2.71 μg/kg). However, the thawing method did not significantly affect the formation of either acrylamide or PAHs. No significant differences in the acrylamide contents were observed among the chicken meat parts, however, the highest PAH contents were found in chicken wings. Thus, the results demonstrated that air frying could reduce the formation of acrylamide and PAHs in chicken meat in comparison with deep-fat frying.
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Gonçalves, Luana, Cristiane Mariote Amaral, Laiza Tatiana Poskus, José Guilherme Antunes Guimarães, and Eduardo Moreira da Silva. "Degradation of Resin Composites in a Simulated Deep Cavity." Brazilian Dental Journal 25, no. 6 (December 2014): 532–37. http://dx.doi.org/10.1590/0103-6440201300089.
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The aim of this study was to analyze the sorption and solubility of a nanofilled (Filtek Z350) and a midifilled (Filtek P60) resin composite in oral environment-like substances, in a simulated deep cavity. A cylindrical cavity prepared in a bovine incisor root was incrementally filled with resin composites. The obtained resin composite cylinders were cut perpendicularly to the axis to obtain 1-mm-thick discs that were divided into fifteen groups (n=5) according to depth (1, 2, 3, 4 and 5 mm) and immersion media (distilled water - DW, artificial saliva - AS and lactic acid - LA). The sorption and solubility were calculated based on ISO 4049:2000. Additionally, the degree of conversion (DC%) was calculated by FT-IR spectroscopy. Data were analyzed using multifactor analysis of variance (MANOVA) followed by Tukey's HSD post-hoc test and linear regression analysis (a=0.05). The DC% was higher for the midifilled resin composite and was negatively influenced by cavity depth (p<0.05). The nanofilled resin composite presented higher sorption and solubility than did the midifilled (p<0.05). The immersion media influenced the sorption and the solubility as follows: LA>AS>DW, (p<0.05). Both phenomena were influenced by cavity depth, with the sorption and solubility increasing from 1 to 5 mm (p<0.05). The degradation of resin composite restorations may be greater in the deepest regions of class II restorations when the composite is exposed to organic acids present in the oral biofilm (lactic acid).
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Dong, Chen-Yuan, Betty Yu, Peter D. Kaplan, and Peter T. C. So. "Performances of high numerical aperture water and oil immersion objective in deep-tissue, multi-photon microscopic imaging of excised human skin." Microscopy Research and Technique 63, no. 1 (2003): 81–86. http://dx.doi.org/10.1002/jemt.10431.
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Jacob, Robin H., and David L. Hopkins. "Techniques to reduce the temperature of beef muscle early in the post mortem period – a review." Animal Production Science 54, no. 4 (2014): 482. http://dx.doi.org/10.1071/an12338.
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A review of the literature was conducted on the effects of high temperature and low pH (HTLP) on meat quality, with a focus on interventions that increase the rate of cooling post slaughter. HTLP can potentially change meat tenderness, water-holding capacity and colour due primarily to protein denaturation during the first 5 h post mortem. Deep muscles in large carcasses are susceptible to HTLP when cooled conventionally. Ante mortem and post mortem solutions that increase the rate of carcass cooling are discussed. Ante mortem solutions include access to feed and water, showering with water and provision of shade. Post mortem solutions included vascular flushing, hot fat trimming, opening seams, hot boning, spray chilling, blast chilling, immersion cooling, and very fast chilling. Accelerating rigor with electrical stimulation before HTLP remains controversial. Combinations of different techniques, that suit the specific requirements of a particular processing plant, is the likely best solution to HTLP, but further development of commercial solutions is suggested.
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Rocha, Helena A., Daniel A. Marinho, Nuno D. Garrido, Liliane S. Morgado, and Aldo M. Costa. "The acquisition of aquatic skills in preschool children: deep versus shallow water swimming lessons." Motricidade 14, no. 1 (May 24, 2018): 66. http://dx.doi.org/10.6063/motricidade.13724.
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One of the key factors in the swimming teaching-learning process seems to be the variation of water’s depth.However, there are almost no studies about this topic and the existing ones usually follow a basic approach and with no control of the educational program used. It was our purpose to determine the effect of deep versus shallow water differences on developing pre-schoolers’ aquatic skills after 6 months of practice. Twenty-one Portuguese school-aged children of both genders (4.70 ± 0.51 yrs.), inexperienced in aquatic programs, participated in this study. The children were divided into two groups performing a similar aquatic program but in a different water depth: shallow water (n=10) and deep water (n=11). Each participant was evaluated twice for their aquatic readiness using an observation check list of 17 aquatic motor skills: during the first session (T0) and after six months of practice (two sessions per week with a total of 48 sessions) (T1). The aquatic proficiency on each skill was compared between the groups and a stepwise discriminant analysis was conducted to predict the conditions with higher or lower aquatic competence. Results suggested that swimming practice contributed positively to improvements on several basic aquatic skills, in both groups. The results showed that shallow water group managed to acquire a higher degree of aquatic competence particularly in five basic aquatic skills (p< .05): breath control combined with face immersion and eye opening; horizontal buoyancy; body position at ventral gliding; body position at dorsal gliding; leg kick with breath control at ventral body position, without any flutter device. The discriminant function revealed a significant association between both groups and four included factors (aquatic skills) (p< .001), accounting for 88% between group variability. The body position at ventral gliding was the main relevant predictor (r=0.535). Shallow water swimming lessons generated greater aquatic competence in preschool children after a period of 6 months of practice.
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Лычева, Н. А., И. И. Шахматов, Д. А. Макушкина, and А. В. Седов. "The state of rat hemostasis system under the action of a single exposure to immersion hypothermia." ZHurnal «Patologicheskaia fiziologiia i eksperimental`naia terapiia», no. 4() (November 21, 2018): 93–97. http://dx.doi.org/10.25557/0031-2991.2018.04.93-97.
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Цель - изучение системы гемостаза при однократной иммерсионной гипотермии у крыс. Методика. Исследования выполнены на 40 крысах-самцах Wistar, массой 300 ± 15 г. Иммерсионную гипотермию моделировали путем погружения находящихся в индивидуальных клетках животных в воду с температурой 5°С при t воздуха 7°С. Критерием прекращения воздействия служило снижение у экспериментальных животных ректальной температуры до 10-16°С, что соответствовало сверхглубокой степени гипотермии. Время экспозиции было индивидуальным и составило 55 ± 5 мин. Контролем служила кровь 20 животных, подвергшихся аналогичной процедуре при температуре воды 30°C и воздуха 22-25°С. Время экспозиции соответствовало времени охлаждения животных опытной группы. В дальнейшем все животные были разделены на 4 группы. У животных 1-й группы (контроль) забор крови осуществлялся сразу после извлечения из воды. У животных 2-й группы (опытная) сразу по достижении сверхглубокой степени гипотермии. В 3-й группе - кровь забирали через 24 ч после извлечения из теплой воды (контроль). В 4-й группе забор крови осуществлялся через 24 ч после прекращения охлаждения (опытная). Результаты. Сравнительный анализ результатов показал, что сразу по окончании однократного холодового воздействия наблюдалось увеличение агрегационной активности тромбоцитов и развитие гипокоагуляционных сдвигов, снижение концентрации антитромбина III на фоне повышения концентрации фибриногена и угнетения активности фибринолитического звена системы гемостаза. Описанный гемостазиологический статус укладывается в картину формирования дистрессорной реакции в ответ на однократное действие раздражителя. Через 1 сут. после достижения экспериментальными животными критической температуры ядра в кровотоке сохранялись гипокоагуляционные сдвиги, увеличивалась концентрация фибриногена и регистрировалось появление маркеров тромбинемии. Таким образом, через 1 сут. после общего переохлаждения сохранялся риск развития состояния тромботической готовности и усиливалось состояние дистресса. Заключение. Признаки нарушения гемостазиологических свойств крови, зафиксированные сразу после прекращения охлаждения, через сутки усугубляются появлением в кровотоке маркеров тромбинемии. Aim. To study the state of rat hemostasis system during hypothermia and in post-hypothermic period. Methods. The study was performed on 40 Wistar male rats weighing 300 ± 15 g. Immersion hypothermia was modeled by placing the animals in individual cells in water at a water temperature of 5°C and an air temperature of 7°C. The criterion for terminating the exposure was a decrease in rectal temperature to 10-16°C, which corresponded to ultra-deep hypothermia. Exposure time was individual and averaged 55 ± 5 minutes. The control was the blood of 20 animals withdrawn after they had been placed in water in individual cells at a water temperature of 30°C and an air temperature of 22-25°C. The exposure time was similar to the cooling time of animals of the experimental group. Then all animals were divided into 4 groups. In the first group (control), blood was withdrawn immediately after removing the rats from water. In the second group (experimental) - immediately after reaching ultra-deep hypothermia. In the third group - at 24 hours after removing the rats from water (control). In the fourth group - at 24 hours after the end of cooling (experimental). Results. Comparative analysis of the results showed that immediately after the end of single cold exposure, the platelet aggregation activity was increased with development of hypocoagulation shifts, and the аntithrombin III concentration was decreased, which was associated with increased fibrinogen concentration and inhibition of the fibrinolytic system activity. The described hemostasiological status fits into the picture of a distress response to a single action of the stimulus. One day after the experimental animals have reached the critical core temperature, hypocoagulation shifts persisted in the blood, fibrinogen concentration increased, and thrombinemia markers emerged. Therefore, one day after general hypothermia, the risk for developing the state of thrombotic readiness remained, and the state of distress increased. Conclusions. The signs of impaired hemostasiological properties of the blood observed immediately after the end of cooling were aggravated in 24 hours by emergence of thrombinemia markers in the blood.
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Barrile, V., A. Fotia, and E. Bernardo. "THE SUBMERGED HERITAGE: A VIRTUAL JOURNEY IN OUR SEABED." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W10 (April 17, 2019): 17–24. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w10-17-2019.
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<p><strong>Abstract.</strong> On 21 and 22 August 1972, a young diver near the coast of Riace Marina (South Italy) found two bronze statues representing one of the highest moments of the sculptural production and the most important archaeological discovery of the last century: the Riace Bronzes. The Geomatics Laboratory of the Mediterranean University of Reggio Calabria sets a goal to relive and re-propose the experience of a real immersion and the exciting moment of the discovery: an immersive journey in the interest of interactivity in virtual reality. Immersive Virtual Reality tries to combine the real and the virtual world, even involving our senses. In other words, it allows us to enter into the scenery like the virtual reality one, but without being just simple spectators. We become protagonists and we can participate and decide what to do and how to do it. Unity 3D is the multi-platform development environment used. The scenarios and the objects included in the scene from three-dimensional models were realized through photogrammetric techniques (seabed and bronzes). Remote Operated Vehicles (ROVs) have been widely used in recent times by researchers to explore underwater environments, both in shallow and deep water, for different types of studies. The seabed was detected through the aid of an experimental ROV (realized in a broader project of agreement with the IPCF CNR Messina). The use of a grid of known dimensions assisted the ROV’s use in order to correct the effects of distortion effects obtained in water. The proposed app is still being perfected and completed.</p>
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Karnia, Mateusz Jakub, Daria Korewo, Dorota Myślińska, Ziemowit Maciej Ciepielewski, Monika Puchalska, Klaudia Konieczna-Wolska, Konrad Kowalski, and Jan Jacek Kaczor. "The Positive Impact of Vitamin D on Glucocorticoid-Dependent Skeletal Muscle Atrophy." Nutrients 13, no. 3 (March 14, 2021): 936. http://dx.doi.org/10.3390/nu13030936.
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(1) The study aimed to investigate whether vitamin D3 supplementation would positively affect rats with glucocorticoids-induced muscle atrophy as measured by skeletal muscle mass in two experimental conditions: chronic dexamethasone (DEX) administration and a model of the chronic stress response. (2) The study lasted 28 consecutive days and was performed on 45 male Wistar rats randomly divided into six groups. These included two groups treated by abdominal injection of DEX at a dose of 2 mg/kg/day supplemented with vegetable oil (DEX PL; n = 7) or with vitamin D3 600 IU/kg/day (DEX SUP; n = 8), respectively, and a control group treated with an abdominal injection of saline (CON; n = 6). In addition, there were two groups of rats chronically stressed by cold water immersion (1 hour/day in a glass box with 1-cm-deep ice/water mixture; temperature ~4 °C), which were supplemented with vegetable oil as a placebo (STR PL; n = 9) or vitamin D3 at 600 IU/kg/day (STR SUP; n = 9). The last group was of sham-stressed rats (SHM; n = 6). Blood, soleus, extensor digitorum longus, gastrocnemius, tibialis anterior, and quadriceps femoris muscles were collected and weighed. The heart, liver, spleen, and thymus were removed and weighed immediately after sacrifice. The plasma corticosterone (CORT) and vitamin D3 metabolites were measured. (3) We found elevated CORT levels in both cold water-immersed groups; however, they did not alter body and muscle weight. Body weight and muscle loss occurred in groups with exogenously administered DEX, with the exception of the soleus muscle in rats supplemented with vitamin D3. Decreased serum 25(OH)D3 concentrations in DEX-treated rats were observed, and the cold water immersion did not affect vitamin D3 levels. (4) Our results indicate that DEX-induced muscle loss was abolished in rats supplemented with vitamin D3, especially in the soleus muscle.
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Rhys Evans, PH, and M. Cameron. "Aural exostoses (surfer’s ear) provide vital fossil evidence of an aquatic phase in Man’s early evolution." Annals of The Royal College of Surgeons of England 99, no. 8 (November 2017): 594–601. http://dx.doi.org/10.1308/rcsann.2017.0162.
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For over a century, otolaryngologists have recognised the condition of aural exostoses, but their significance and aetiology remains obscure, although they tend to be associated with frequent swimming and cold water immersion of the auditory canal. The fact that this condition is usually bilateral is predictable since both ears are immersed in water. However, why do exostoses only grow in swimmers and why do they grow in the deep bony meatus at two or three constant sites? Furthermore, from an evolutionary point of view, what is or was the purpose and function of these rather incongruous protrusions? In recent decades, paleoanthropological evidence has challenged ideas about early hominid evolution. In 1992 the senior author suggested that aural exostoses were evolved in early hominid Man for protection of the delicate tympanic membrane during swimming and diving by narrowing the ear canal in a similar fashion to other semiaquatic species. We now provide evidence for this theory and propose an aetiological explanation for the formation of exostoses.
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Hüttel, Moritz, Tobias Golditz, Isabel Mayer, Rafael Heiss, Christoph Lutter, Matthias Wilhelm Hoppe, Martin Engelhardt, et al. "Effects of Pre- and Post-Exercise Cold-Water Immersion Therapy on Passive Muscle Stiffness." Sportverletzung · Sportschaden 34, no. 02 (July 18, 2019): 72–78. http://dx.doi.org/10.1055/a-0854-8302.
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Abstract Background Cold-water immersion (CWI) has become a popular preventive, regenerative and performance-enhancing intervention in various sports. However, its effects on soft tissue, including changes of intramuscular stiffness, are poorly understood. The purpose of this study was to investigate the effect of CWI on muscle stiffness. Patients/Material and Methods Thirty healthy participants were included and divided into the three following groups (n = 10): 1) post-ESU group: exercise and CWI (post-exercise set-up); 2) control group: exercise without CWI (control condition); 3) pre-ESU group: CWI alone (pre-exercise set-up). Acoustic radiation force impulse (ARFI) elastography was conducted to assess tissue stiffness (shear wave velocity, SWV). Values obtained at resting conditions (baseline, t0) were compared to values post-exercise (t1, for post-ESU group and control group), post-CWI (t2, for post-ESU group and pre-ESU group; rest for control group) and to 60-min follow-up time (t3, for all groups). Data were assessed in superficial and deep muscle tissue (rectus femoris muscle, RF; vastus intermedius muscle, VI). Results For the post-ESU group (CWI post-exercise), there was no significant difference between the time points of measurements: exercise (t1: RF: 1.63 m/s; VI: 1.54 m/s), CWI (t2: RF: 1.63 m/s; VI: 1.53 m/s) and at 60-min follow-up (t3: RF: 1.72 m/s; VI: 1.61 m/s). In the control group, a significant decrease of SWV was found between baseline conditions at t0 and post-exercise (t1) at VI (VI: 1.37 m/s; p = 0.004; RF: 1.59 m/s; p = 0.084). For t2 and t3, no further significant changes were detected. Regarding the pre-exercise set-up (pre-ESU group), a significant decrease in SWV from baseline to t2 in VI (1.60 m/s to 1.49 m/s; VI: p = 0.027) was found. Conclusion This study shows varying influences of CWI on muscle stiffness. Overall, we did not detect any significant effects of CWI on muscle stiffness post-exercise. Muscle stiffness-related effects of CWI differ in the context of a pre- or post-exercise condition and have to be considered in the implementation of CWI to ensure its potential preventive and regenerative benefits.
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Kempton, Karl. "The Ramadan Sonnets." American Journal of Islam and Society 14, no. 1 (April 1, 1997): 129. http://dx.doi.org/10.35632/ajis.v14i1.2264.
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Best book of poems I’ve read in years by a contemporary and have had thepleasure of being lifted by, shot into the orbit of harmonious rapture grins andthe joyousness of countless YES, O, YES. The collection resonates and purifiesthe deep sweet water in the cells where the real self drinks. The resonatingbuilds stanza by stanza, poem after poem, informed by an American spiritualand mystical lineage from Transcendentalism to the Beats of the BeatitudeVision into as-yet-to-be identified and named Third Wave, holding in itsunnumbered beckoning hands the world‘s mystical poetry body. Moore’s spectacularcontribution to this present building surge arrives before his audiencewith a thorough immersion in Islam’s Sufi way. This is experience inspired intosong, not a complex geometry of imaginary gymnastics afloat in an alienatedmental life ...
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Fagius, Jan. "Muscle Nerve Sympathetic Activity In Migraine. Lack of Abnormality." Cephalalgia 5, no. 4 (December 1985): 197–203. http://dx.doi.org/10.1046/j.1468-2982.1985.0504197.x.
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Microelectrode recordings of muscle nerve sympathetic activity (MSA) in the peroneal nerve were performed in eight patients with common migraine, when they were free of headache and during a spontaneously occurring attack of migraine. During the migraine headache all subjects remained on the same level of MSA as in the control situation and the responses to manoeuvres (slow deep breathing, the Valsalva manoeuvre, sustained hand grip, immersion of one hand into ice water) showed no qualitative or quantitative change. Assessment of vagal influence on the heart showed no change from control situation to attack of migraine. The study provides direct evidence against the existence of any abnormality of MSA during ongoing migraine headache and does not support the assumption that migraine is a generalized vasomotor disorder. No conclusions about possible dysfunction in other parts of the sympathetic nervous system can be drawn.
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Mohd Nasib, Amira, Irfan Hatim, Nora Jullok, and Syahmie Rasidi. "Preparation of supported-deep eutectic solvent membranes: Effects of bath medium composition on the structure and performance of supported-deep eutectic solvent membrane for CO2/N2 gas separation." Malaysian Journal of Fundamental and Applied Sciences 16, no. 3 (June 15, 2020): 338–41. http://dx.doi.org/10.11113/mjfas.v16n3.1485.
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Polyvinylidene fluoride-co-polytetrafluoroethylene, PVDF-co-PTFE polymer was used as a membrane support. The asymmetric membranes were formed by immersion of casted membrane film into the coagulation bath. This work manipulated the coagulant bath medium by mixing ethanol with distilled water at different weight percentages (0, 25 and 50 wt. % of ethanol). The structures of fabricated membranes were observed to have different morphologies. Higher ethanol content altered the membrane structure from finger-like to sponge-like structure, and hence differed in membrane porosity. Vacuum-based technique was chosen to impregnate the deep eutectic solvent (DES) into the pores of membrane support. DES was prepared by mixing choline chloride (ChCl) and ethylene glycol at a ratio of 1:3. Scanning electron microscopy (SEM) was used to study the membrane morphology changes while in order to determine the immobilization of DES, energy dispersive X-ray (EDX) analysis was used. The porosity of fabricated PVDF-co-PTFE membrane was determined by means of gravimetric method. Lastly, the membrane separation performance using CO2 and N2 gasses were used to determine the capability of the supported-DES-membrane. The results demonstrated the highest immobilization of DES in supported membrane pores was achieved when combination of 25 wt. % of ethanol and 75 wt. % distilled water was used as a coagulant bath medium. The respective membrane has 74.5% porosity with the most excellent performance of CO2 separation at 25.5 x 103 GPU with CO2/N2 selectivity of 2.89.
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Portella, Fernando Freitas, Fabrício Mezzomo Collares, Paula Dapper Santos, Cláudia Sartori, Everton Wegner, Vicente Castelo Branco Leitune, and Susana Maria Werner Samuel. "Glycerol Salicylate-based Pulp-Capping Material Containing Portland Cement." Brazilian Dental Journal 26, no. 4 (August 2015): 357–62. http://dx.doi.org/10.1590/0103-6440201300218.
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<p>The purpose of this study was to evaluate the water sorption, solubility, pH and ability to diffuse into dentin of a glycerol salicylate-based, pulp-capping cement in comparison to a conventional calcium hydroxide-based pulp capping material (Hydcal). An experimental cement was developed containing 60% glycerol salicylate resin, 10% methyl salicylate, 25% calcium hydroxide and 5% Portland cement. Water sorption and solubility were determined based on mass changes in the samples before and after the immersion in distilled water for 7 days. Material discs were stored in distilled water for 24 h, 7 days and 28 days, and a digital pHmeter was used to measure the pH of water. The cement's ability to diffuse into bovine dentin was assessed by Raman spectroscopy. The glycerol salicylate-based cement presented higher water sorption and lower solubility than Hydcal. The pH of water used to store the samples increased for both cements, reaching 12.59±0.06 and 12.54±0.05 after 7 days, for Hydcal and glycerol salicylate-based cements, respectively. Both cements were able to turn alkaline the medium at 24 h and sustain its alkalinity after 28 days. Hydcal exhibited an intense diffusion into dentin up to 40 µm deep, and the glycerol salicylate-based cement penetrated 20 µm. The experimental glycerol salicylate-based cement presents good sorption, solubility, ability to alkalize the surrounding tissues and diffusion into dentin to be used as pulp capping material.</p>
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Hood, David D., James C. Eisenach, and Robin Tuttle. "Phase I Safety Assessment of Intrathecal Neostigmine Methylsulfate in Humans." Anesthesiology 82, no. 2 (February 1, 1995): 331–43. http://dx.doi.org/10.1097/00000542-199502000-00003.
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Background In dogs, sheep, and rats, spinal neostigmine produces analgesia alone and enhances analgesia from alpha 2-adrenergic agonists. This study assesses side effects and analgesia from intrathecal neostigmine in healthy volunteers. Methods After institutional review board approval and informed consent, 28 healthy volunteers were studied. The first 14 volunteers received neostigmine (50-750 micrograms) through a #19.5 spinal needle followed by insertion of a spinal catheter. The remaining 14 volunteers received neostigmine through a #25 or #27 spinal needle without a catheter. Safety measurements included blood pressure, heart rate, oxyhemoglobin saturation, end-tidal carbon dioxide, neurologic evaluation, and computer tests of vigilance and memory. Analgesia in response to ice water immersion was measured. Results Neostigmine (50 micrograms) through the #19.5 needle did not affect any measured variable. Neostigmine (150 micrograms) caused mild nausea, and 500-750 micrograms caused severe nausea and vomiting. Neostigmine (150-750 micrograms) produced subjective leg weakness, decreased deep tendon reflexes, and sedation. The 750-micrograms dose was associated with anxiety, increased blood pressure and heart rate, and decreased end-tidal carbon dioxide. Neostigmine (100-200 micrograms) in saline, injected through a #25 or #27 needle, caused protracted, severe nausea, and vomiting. This did not occur when dextrose was added to neostigmine. Neostigmine by either method of administration reduced visual analog pain scores to immersion of the foot in ice water. Conclusions The incidence and severity of these adverse events from intrathecal neostigmine appears to be affected by dose, method of administration, and baricity of solution. These effects in humans are consistent with studies in animals. Because no unexpected or dangerous side effects occurred, cautious examination of intrathecal neostigmine alone and in combination with other agents for analgesia is warranted.
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Tetzlaff, Kay, and Paul S. Thomas. "Short- and long-term effects of diving on pulmonary function." European Respiratory Review 26, no. 143 (March 29, 2017): 160097. http://dx.doi.org/10.1183/16000617.0097-2016.
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The diving environment provides a challenge to the lung, including exposure to high ambient pressure, altered gas characteristics and cardiovascular effects on the pulmonary circulation. Several factors associated with diving affect pulmonary function acutely and can potentially cause prolonged effects that may accumulate gradually with repeated diving exposure. Evidence from experimental deep dives and longitudinal studies suggests long-term adverse effects of diving on the lungs in commercial deep divers, such as the development of small airways disease and accelerated loss of lung function. In addition, there is an accumulating body of evidence that diving with self-contained underwater breathing apparatus (scuba) may not be associated with deleterious effects on pulmonary function. Although changes in pulmonary function after single scuba dives have been found to be associated with immersion, ambient cold temperatures and decompression stress, changes in lung function were small and suggest a low likelihood of clinical significance. Recent evidence points to no accelerated loss of lung function in military or recreational scuba divers over time. Thus, the impact of diving on pulmonary function largely depends on factors associated with the individual diving exposure. However, in susceptible subjects clinically relevant worsening of lung function may occur even after single shallow-water scuba dives.
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Ageenkov, E. V., A. A. Sitnikov, and E. N. Vodneva. "Influence of the probe dimensions on the display of the low-frequency dispersion of the earth’s electromagnetic properties for measure-ments in marine waters up to 100 m deep." Earth sciences and subsoil use 43, no. 3 (October 7, 2020): 325–38. http://dx.doi.org/10.21285/2686-9993-2020-43-3-325-338.
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The purpose of the study is to show the effect of the probe dimensions on the display of the low-frequency dispersion of the geological formations’ electromagnetic properties in transient measurements by electric lines in the axial area of the source for the water areas up to 100 m deep. The study analyzes the change in the transient signal, the finite difference, and the transform (the ratio of the above two) as a function of the length of the source (a horizontal grounded electric line (AB) 50 to 2,000 m), the receiver (a three-electrode electric line (MON) 50 to 2,000 m), and the distance between their centers (spacing) 100 to 4,000 m. The values obtained from the conductive and conductive polarizing models are compared for the identical probes installed at the same depth. The grounded electric line is located within the conducting medium with a conductive polarizable base. The conducting medium is associated with the seawater thickness in the marine shelves up to 100 m deep. The conductive polarizable base is a geological environment (earth) covered with a layer of water. The polarizability of the base is registered by introducing frequency-dependent electrical resistivity by the Cole-Cole formula. The calculations show the display of different transient components associated with the transient buildup and the earth’s low-dispersion properties caused by both galvanic and eddy currents. These components manifest themselves differently for the probes with different dimensions of the source line, receiving line, and spacing. Based on the calculations, it can be argued that in the time range from 1 ms to 16 s, at the probes that have different dimensions and are immersed in the water layer up to 100 m thick, the signal changes depending on the immersion depth for “small” installations (AB of 50 and 100 m), while there is no such dependence for the rest of the probes used in the calculations (AB of 250, 500, 1,000, and 2,000 m).
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Zhu, Yimo, Liang Chen, Heng Zhang, Zelin Zhou, and Shougen Chen. "Physical and Mechanical Characteristics of Soft Rock Tunnel and the Effect of Excavation on Supporting Structure." Applied Sciences 9, no. 8 (April 12, 2019): 1517. http://dx.doi.org/10.3390/app9081517.
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The problem of large deformation is very prominent in deep-buried tunnel excavation in soft rock, which brings serious potential safety hazards and economic losses to projects. The knowledge of deformation law and support measures is the key to ensure the rational design and safe construction in a large deformation tunnel of soft rock. This paper describes rock physical and mechanical tests and field monitoring is employed to investigate the cause and development process of large deformation in Dongsong hydropower station in Sichuan Province, China. The results show that the free expansion rate of the rock sample is 20.0%, the average expansion stress of the rock sample is 11.0 kPa, and the expansibility of the rock is low. Large deformation of surrounding rock mainly comes from the dilatancy effect with high geostress and relaxation deformation with weak support. Shotcrete sealing exposed surrounding rock, and early strength support avoiding water immersion are useful to deal with the three main factors (weathering, water and confining pressure) that affect the strength of surrounding rocks. The second lining applied in time can effectively limit the further development of stress and deformation of initial support, and prevent the cracking and large deformation of concrete. Clearance convergence is suggested to be the main monitoring work in construction, because of its advantages of intuitive results, easy quality assurance of instrument installation and high accuracy.
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Saleeby, Stephen M., and Susan C. van den Heever. "Developments in the CSU-RAMS Aerosol Model: Emissions, Nucleation, Regeneration, Deposition, and Radiation." Journal of Applied Meteorology and Climatology 52, no. 12 (December 2013): 2601–22. http://dx.doi.org/10.1175/jamc-d-12-0312.1.
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AbstractThe Colorado State University (CSU) Regional Atmospheric Modeling System (RAMS) has undergone development focused on improving the treatment of aerosols in the microphysics model, with the goal of examining the impacts of aerosol characteristics, scavenging, and regeneration processes, among others, on precipitation processes in clouds ranging from stratocumulus to deep convection and mixed-phase orographic clouds. Improvements in the representation of aerosols allow for more comprehensive studies of aerosol effects on cloud systems across scales. In RAMS there are now sub- and supermicrometer modes of sulfate, mineral dust, sea salt, and regenerated aerosol. All aerosol species can compete for cloud droplet nucleation, and they are regenerated via hydrometeor evaporation. A newly applied heterogeneous ice nuclei parameterization accounts for deposition nucleation and condensation and immersion freezing of aerosols greater than 0.5-μm diameter. There are also schemes for trimodal sea salt emissions and bimodal dust lofting that are functions of wind speed and surface properties. Aerosol wet and dry deposition accounts for collection by falling hydrometeors as well as gravitational settling of aerosols on water, soil, and vegetation. Aerosol radiative effects are parameterized via the Mie theory. An examination of the simulated impact of aerosol characteristics, sources, and sinks reveals mixed sensitivity among cloud types. For example, reduced aerosol solubility has little impact on deep convection since supersaturations are large and nearly all accumulation-mode aerosols activate. In contrast, reduced solubility results in reduced aerosol activation in precipitating stratocumulus. This leads to lower cloud droplet concentration, larger droplet size, and more efficient warm rain processes.
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Whitham, Martin, Stewart J. Laing, Anna Jackson, Norbert Maassen, and Neil P. Walsh. "Effect of exercise with and without a thermal clamp on the plasma heat shock protein 72 response." Journal of Applied Physiology 103, no. 4 (October 2007): 1251–56. http://dx.doi.org/10.1152/japplphysiol.00484.2007.
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The contribution of heat and exercise related stress to the release of heat shock protein 72 (HSP72) is currently unknown. The purpose of the present study was to determine the combined and independent effects of heat and exercise on the extracellular (e)HSP72 response. Eleven moderately trained male volunteers [means ± SD: age 21 ± 4 yr; body mass 75.7 ± 7.7 kg; maximal oxygen uptake (V̇o2 max) 57.8 ± 3.3 ml·kg−1·min−1] completed four 2-h, heat-manipulated, water-immersion trials. Trials were exercise-induced heat (EIH; rectal temperature change +2.2°C), clamped exercise (CEx; 0°C), passive heating (PHT; +2.3°C), and control (Con; 0°C). Exercise trials (EIH and CEx) comprised deep-water running at 58.5 ± 2.4 and 59.1 ± 1.7% v̇o2max. eHSP72 and catecholamine concentrations were determined by ELISA and HPLC, respectively, pre- and postimmersion. All trials induced an eHSP72 response ( P < 0.05) with postimmersion values significantly greater on EIH compared with other trials (6.0 ± 3.4; CEx 3.8 ± 2.6; PHT 2.7 ± 2.1; Con 2.2 ± 1.9 ng/ml). Exercising with a thermal clamp blunted the eHSP72 response, but postimmersion values were also greater than Con. PHT induced a large catecholamine response, but postimmersion eHSP72 values did not reach significance vs. Con. Given that exercising with a thermal clamp evoked a significant increase in plasma eHSP72 concentration, exercise-related stressors other than heat appeared influential in stimulating HSP72 release. Moreover, the catecholamine data from PHT suggest neither epinephrine nor norepinephrine was solely responsible for eHSP72 release.
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Nakamori, T., A. Morimoto, K. Morimoto, N. Tan, and N. Murakami. "Effects of alpha- and beta-adrenergic antagonists on rise in body temperature induced by psychological stress in rats." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 264, no. 1 (January 1, 1993): R156—R161. http://dx.doi.org/10.1152/ajpregu.1993.264.1.r156.
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We investigated the effects of intraperitoneal injection of alpha- and beta-adrenergic antagonists on psychological stress-induced responses in free-moving rats. Psychological stress was induced by immersion in 2-cm-deep water. The intraperitoneal injection of the alpha-adrenergic blocker, phentolamine (10 mg/kg), attenuated the stress-induced rise in body temperature and hypertension but enhanced tachycardia. In contrast, intraperitoneal injection of the beta-adrenergic blocker, propranolol (1 mg/kg), suppressed tachycardia but had no effect on rise in body temperature and hypertension during stress. The intraperitoneal injection of both blockers had no effect on the increase in metabolic rate (O2 consumption) induced by stress. The intravenous injection of propranolol (1 mg/kg) suppressed the stress-induced rise in body temperature. We then examined the effect of intracerebroventricular injection of propranolol on the stress-induced rise in body temperature and found that intracerebroventricular injection of propranolol (50 micrograms) suppressed the stress-induced rise in body temperature. These results support the following hypotheses: 1) Systemic injection of phentolamine suppresses the psychological stress-induced rise in body temperature by facilitating heat-loss; 2) Peripheral beta-adrenergic stimulation probably does not contribute to psychological stress-induced rises in body temperature; and 3) central beta-adrenergic receptors are important in stress-induced increases in body temperature.
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Diao, Minghui, George H. Bryan, Hugh Morrison, and Jorgen B. Jensen. "Ice Nucleation Parameterization and Relative Humidity Distribution in Idealized Squall-Line Simulations." Journal of the Atmospheric Sciences 74, no. 9 (August 16, 2017): 2761–87. http://dx.doi.org/10.1175/jas-d-16-0356.1.
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Abstract Output from idealized simulations of a squall line are compared with in situ aircraft-based observations from the Deep Convective Clouds and Chemistry campaign. Relative humidity distributions around convection are compared between 1-Hz aircraft observations (≈250-m horizontal scale) and simulations using a double-moment bulk microphysics scheme at three horizontal grid spacings: Δx = 0.25, 1, and 4 km. The comparisons focus on the horizontal extent of ice supersaturated regions (ISSRs), the maximum and average relative humidity with respect to ice (RHi) in ISSRs, and the ice microphysical properties during cirrus cloud evolution, with simulations at 0.25 and 1 km providing better results than the 4-km simulation. Within the ISSRs, all the simulations represent the dominant contributions of water vapor horizontal heterogeneities to ISSR formation on average, but with larger variabilities in such contributions than the observations. The best results are produced by a Δx = 0.25-km simulation with the RHi threshold for initiating ice nucleation increased to 130%, which improves almost all the ISSR characteristics and allows for larger magnitude and frequency of ice supersaturation (ISS) > 8%. This simulation also allows more occurrences of clear-sky ISSRs and a higher spatial fraction of ISS for in-cloud conditions, which are consistent with the observations. These improvements are not reproduced by modifying other ice microphysical processes, such as a factor-of-2 reduction in the ice nuclei concentration; a factor-of-10 reduction in the vapor deposition rate; turning off heterogeneous contact and immersion freezing; or turning off homogeneous freezing of liquid water.
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Laing, Stewart J., Anna R. Jackson, Robert Walters, Enid Lloyd-Jones, Martin Whitham, Norbert Maassen, and Neil P. Walsh. "Human blood neutrophil responses to prolonged exercise with and without a thermal clamp." Journal of Applied Physiology 104, no. 1 (January 2008): 20–26. http://dx.doi.org/10.1152/japplphysiol.00792.2007.
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The purpose of this study was to investigate the effects of prolonged exercise with and without a thermal clamp on neutrophil trafficking, bacterial-stimulated neutrophil degranulation, stress hormones, and cytokine responses. Thirteen healthy male volunteers (means ± SE: age 21 ± 1 yr; mass 74.9 ± 2.1 kg; maximal oxygen uptake 58 ± 1 ml·kg−1·min−1) completed four randomly assigned, 2-h water-immersion trials separated by 7 days. Trials were exercise-induced heating (EX-H: water temperature 36°C), exercise with a thermal clamp (EX-C: 24°C), passive heating (PA-H: 38.5°C), and control (CON: 35°C). EX-H and EX-C was comprised of 2 h of deep water running at 58% maximal oxygen uptake. Blood samples were collected at pre-, post-, and 1 h postimmersion. Core body temperature was unaltered on CON, clamped on EX-C (−0.02°C), and rose by 2.23°C and 2.31°C on EX-H and PA-H, respectively. Exercising with a thermal clamp did not blunt the neutrophilia postexercise (EX-C postexercise: 9.6 ± 1.1 and EX-H postexercise: 9.8 ± 1.0 × 109/liter). Neutrophil degranulation decreased ( P < 0.01) similarly immediately after PA-H (−21%), EX-C, and EX-H (−28%). EX-C blunted the circulating norepinephrine, cortisol, granulocyte-colony stimulating factor, and IL-6 response ( P < 0.01) but not the plasma epinephrine and serum growth hormone response. These results show a similar neutrophilia and decrease in neutrophil degranulation after prolonged exercise with and without a thermal clamp. As such, the rise in core body temperature does not appear to mediate neutrophil trafficking and degranulation responses to prolonged exercise. In addition, these results suggest a limited role for cortisol, granulocyte-colony stimulating factor, and IL-6 in the observed neutrophil responses to prolonged exercise.
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Smilanick, J. L., M. F. Mansour, D. A. Margosan, F. Mlikota Gabler, and W. R. Goodwine. "Influence of pH and NaHCO3 on Effectiveness of Imazalil to Inhibit Germination of Penicillium digitatum and to Control Postharvest Green Mold on Citrus Fruit." Plant Disease 89, no. 6 (June 2005): 640–48. http://dx.doi.org/10.1094/pd-89-0640.
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In vitro, spores of Penicillium digitatum germinated without inhibition between pH 4 and 7, but were inhibited at higher pH. Estimated concentrations of imazalil (IMZ) in potato-dextrose broth-Tris that caused 50% reduction in the germination of spores (ED50) of an IMZ-sensitive isolate M6R at pH 4, 5, 6, and 7 were 0.16, 0.11, 0.015, and 0.006 μg/ml, respectively. ED50 IMZ concentrations of an IMZ-resistant isolate D201 at pH 4, 5, 6, and 7 were 5.9, 1.4, 0.26, and 0.07 μg/ml, respectively. The natural pH within 2-mm-deep wounds on lemon was 5.6 to 5.1 and decreased with fruit age. IMZ effectiveness to control green mold and its residues increased with pH. The pH in wounds on lemon fruit 24 h after immersion in 1, 2, or 3% NaHCO3 increased from pH 5.3 to 6.0, 6.3, and 6.7, respectively. NaHCO3 dramatically improved IMZ performance. Green mold incidence among lemon fruit inoculated with M6R and treated 24 h later with IMZ at 10 μg/ml, 1% NaHCO3, or their combination was 92, 55, and 22%, respectively. Green mold among lemon fruit inoculated with D201 and treated 24 h later with water, IMZ at 500 μg/ml, 3% NaHCO3, or their combination was 96.3, 63.0, 44.4, and 6.5%, respectively. NaHCO3 did not influence IMZ fruit residue levels.
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Zhou, Yong, Pei Zhang, Jinping Xiong, and Fuan Yan. "The corrosion behavior of chromated AA2024 aluminum alloy in 3.5% NaCl solution." Anti-Corrosion Methods and Materials 66, no. 6 (November 4, 2019): 879–87. http://dx.doi.org/10.1108/acmm-01-2019-2070.
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Purpose A chromate conversion coating was prepared on the surface of bare AA2024 aluminum alloy by direct immersion in the chromating treatment bath, and the corrosion behavior of chromated AA2024 aluminum alloy in 3.5 per cent NaCl solution was studied by electrochemical measurement and microstructural observation. Design/methodology/approach According to the polarization curve test and the scanning electron microscope observation, the corrosion evolution of chromated AA2024 in 3.5 per cent NaCl solution was divided into the following three stages: coating failure, pitting corrosion and intergranular corrosion (IGC). Findings In the first stage, the chromate coating degraded gradually due to the combined action of chloride anions and water molecules, resulting in the complete exposure of AA2024 substrate to 3.5 per cent NaCl solution. Subsequently, in the second stage, chloride anions adsorbed at the sites of θ phase (Al2Cu) and S phase (Al2CuMg) on the AA2024 surface preferentially, and some corrosion pits initiated at the above two sites and propagated towards the deep of crystal grains. However, the propagation of a pit terminated when the pit front arrived at the adjacent grain boundary, where the initiation of IGC occurred. Originality/value Finally, in the third stage, the corrosion proceeded along the continuous grain boundary net and penetrated the internal of AA2024 substrate, resulting in the propagation of IGC. The related corrosion mechanisms for the bare and the chromated AA2024 were also discussed.
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Archer, D. "A model of the methane cycle, permafrost, and hydrology of the Siberian continental margin." Biogeosciences Discussions 11, no. 6 (June 3, 2014): 7853–900. http://dx.doi.org/10.5194/bgd-11-7853-2014.
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Abstract. A two-dimensional model of a passive continental margin was adapted to the simulation of the methane cycle on Siberian continental shelf and slope, attempting to account for the impacts of glacial/interglacial cycles in sea level, alternately exposing the continental shelf to freezing conditions with deep permafrost formation during glacial times, and immersion in the ocean in interglacial times. The model is used to gauge the impact of the glacial cycles, and potential anthropogenic warming in the deep future, on the atmospheric methane emission flux, and the sensitivities of that flux to processes such as permafrost formation and terrestrial organic carbon (Yedoma) deposition. Hydrological forcing drives a freshening and ventilation of pore waters in areas exposed to the atmosphere, which is not quickly reversed by invasion of seawater upon submergence, since there is no analogous saltwater pump. This hydrological pump changes the salinity enough to affect the stability of permafrost and methane hydrates on the shelf. Permafrost formation inhibits bubble transport through the sediment column, by construction in the model. The impact of permafrost on the methane budget is to replace the bubble flux by offshore groundwater flow containing dissolved methane, rather than accumulating methane for catastrophic release when the permafrost seal fails during warming. By far the largest impact of the glacial/interglacial cycles on the atmospheric methane flux is attenuation by dissolution of bubbles in the ocean when sea level is high. Methane emissions are highest during the regression (soil freezing) part of the cycle, rather than during transgression (thawing). The model-predicted methane flux to the atmosphere in response to a warming climate is small, relative to the global methane production rate, because of the ongoing flooding of the continental shelf. A slight increase due to warming could be completely counteracted by sea level rise on geologic time scales, decreasing the efficiency of bubble transit through the water column. The methane cycle on the shelf responds to climate change on a long time constant of thousands of years, because hydrate is excluded thermodynamically from the permafrost zone by water limitation, leaving the hydrate stability zone at least 300 m below the sediment surface.
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Nagasaka, T., K. Hirata, T. Mano, S. Iwase, and Y. Rossetti. "Heat-induced finger vasoconstriction controlled by skin sympathetic nerve activity." Journal of Applied Physiology 68, no. 1 (January 1, 1990): 71–75. http://dx.doi.org/10.1152/jappl.1990.68.1.71.
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Finger blood flow (BF) and skin sympathetic nerve activity (SSA) to the glabrous side of the hand were measured during immersion of the hand in a water bath in which temperature (Tw) was raised every 10 min by steps of 2 degrees C from 35 or 37 to 41 degrees C. The experiments were conducted during the summer in rooms in which ambient temperature was 28-32 degrees C or 35 degrees C. The nine healthy male subjects were wearing summer clothes. Finger BF through vessels located deep in the skin was measured by using laser-Doppler flowmetry (ALF-2100, Advance). With the use of a tungsten microelectrode SSA was recorded directly from the median nerve at the wrist or antecubital fossa of the tested arm. With finger vessels already dilated at Tw of 35 or 37 degrees C, finger BF decreased, with a concomitant increase in the SSA bursts as Tw rose to 39-41 degrees C. We confirmed in one subject that anesthetic blockade of the median nerve at the site proximal, but not distal, to the recording site blocked responses to the step rise in Tw in the SSA bursts and in finger BF. From these results we conclude that, with the subject in a warm state, blood vessels of the finger respond to local heating with vasoconstriction, and this finger vasoconstriction is evoked reflexively, largely through the increased sympathetic outflow to the resistance vessels of the finger.
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Sieber, Arne, Antonio L'Abbate, Mirko Passera, Erika Garbella, Antonio Benassi, and Remo Bedini. "Underwater study of arterial blood pressure in breath-hold divers." Journal of Applied Physiology 107, no. 5 (November 2009): 1526–31. http://dx.doi.org/10.1152/japplphysiol.91438.2008.
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Knowledge regarding arterial blood pressure (ABP) values during breath-hold diving is scanty. It derives from a few reports of measurements performed at the water's surface, showing slight or no increase in ABP, and from a single study of two simulated deep breath-hold dives in a hyperbaric chamber. Simulated dives showed an increase in ABP to values considered life threatening by standard clinical criteria. For the first time, using a novel noninvasive subaquatic sphygmomanometer, we successfully measured ABP in 10 healthy elite breath-hold divers at a depth of 10 m of freshwater (mfw). ABP was measured in dry conditions, at the surface (head-out immersion), and twice at a depth of 10 mfw. Underwater measurements of ABP were obtained in all subjects. Each measurement lasted 50–60 s and was accomplished without any complications or diver discomfort. In the 10 subjects as a whole, mean ABP values were 124/93 mmHg at the surface and 123/94 mmHg at a depth of 10 mfw. No significant statistical differences were found when blood pressure measurements at the water surface were compared with breath-hold diving conditions at a depth of 10 mfw. No systolic blood pressure values >140 mmHg or diastolic blood pressure values >115 mmHg were recorded. In conclusion, direct measurements of ABP during apnea diving showed no or only mild increases in ABP. However, our results cannot be extended over environmental conditions different from those of the present study.
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Lopushansky, O. M., S. V. Sander, M. M. Ruban, O. P. Fejaga, and V. M. Kroshka. "Substantiation of the method of manufacturing gauze swabs depending on the purpose of use." Reports of Vinnytsia National Medical University 25, no. 1 (March 27, 2021): 97–101. http://dx.doi.org/10.31393/reports-vnmedical-2021-25(1)-18.
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Annotation. Gauze remains the main dressing. It is used to make swabs for drying wounds and dissecting tissues. The purpose of the work is to establish the optimal density of the swab for drainage of the wound and preparation of tissues. Swabs made of 10x12 cm gauze fragments were investigated. The gauze fragments were weighed before and after immersion in water and the absorption capacity per unit dry weight was calculated. The dissecting properties of the swabs were investigated on plasticine blocks, the surface of which was pressed with a force of 12 N. The formed depressions were filled with gypsum. The volume and weight of the casts were determined. To determine the reliability of the difference between the two mean values used the reliability criterion t (Student’s test). It was found that loose swabs absorbed 913.5±43.9% of water, medium density – 766.3±55.2%, dense – 682.9±70.1 (p˂0.05). This is due to the fact that loose swabs have the largest in radius and length of the capillaries. When studying the recesses formed by embossing the swab on the surface of the block, it was found that when using loose swabs formed a deep conical recess, which indicated the risk of injury. When embossed with dry swabs of medium density received molds weighing 0.034±0.0000011 g, wet – 0.033±0.0000011 g (p>0.05). When using dense swabs – 0.037±0.0000011 g and 0.034±0.0000011 g, respectively (p˂0.05). Dense swabs showed the best dissecting properties. When wet, they are slightly but significantly reduced. Medium density swabs have slightly worse dissecting properties. When wet, they did not change significantly. We attribute the decrease in dissecting properties to the displacement of water from the gauze when pressed. Thus, loose swabs (∆M=913.5%±43.9%) absorb fluid best, which determines their predominant use for wound drying. Dense swabs are characterized by the lowest absorption capacity (682.9±70.1%), the best dissecting properties.
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Chamov, N. P., I. E. Stukalova, S. Yu Sokolov, A. A. Peyve, N. V. Gor’kova, A. A. Razumovskiy, M. E. Bylinskaya, and L. A. Golovina. "Tectonic-sedimentary system of the Atlantis-meteor seamounts (North Atlantic): late Miocene to Pliocene volcanic and sedimentary environments and the position within the Atlantic-arctic structures." Литология и полезные ископаемые, no. 5 (October 20, 2019): 418–38. http://dx.doi.org/10.31857/s0024-497x20195418-438.
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The article concerns the original materials obtained in the 33-rd cruise of the R/V Akademik Nikolai Strakhov in the eastern part of the North Atlantic while studying the system of AtlantisMeteor seamounts. The system is a single volcanic uplift formed on the Canary Abyssal Plate, and is one of the key objects for understanding the geological history of this segment of the Atlantic Ocean. The article discusses basalts, tefrites, and organogenic-terrigenous lagoon-marine sediments dredged from the Atlantis, Plateau, and Cruiser seamounts. The petrographic properties and compositions of the basalts of the seamounts Atlantis and Cruiser reflect significant differences in the environments of their effusions. In the first case, well-crystallized, not showing signs of vesicularity, olivine basalts poured out in deep-water conditions. Glassy highly vesicular basalts from the Cruiser seamount are characteristic of shallow subaerial effusions. Evidence has been obtained in favor of the subaerial settings of the accumulation of tefrites from the Plato seamount. The regularities of lithogenetic transformations of organogenic-terrigenous deposits of the Cruiser seamount, exposed to high-temperature effects of subaerial lava flows, are revealed. In the course of volcanogenic-sedimentary lithogenesis, the lignite-like material lost its primary structure, turning into natural anisotropic coke with a wide development of fusinite and pyrofusinite. The authors of the article associate the studied volcanic manifestations with the final (Late MiocenePliocene) stage of volcanism in the seamount system, which preceded the disintegration of the system, its progressive immersion and the transformation of islands into guyots.
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Qi, Meiqin, and Mahesh K. Upadhyaya. "Seed Germination Ecophysiology of Meadow Salsify (Tragopogon pratensis) and Western Salsify (T. dubius)." Weed Science 41, no. 3 (September 1993): 362–68. http://dx.doi.org/10.1017/s0043174500052061.
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To understand persistence strategies of meadow and western salsify, ecophysiological characteristics of their seed germination were studied. Anaerobiosis (immersion in deoxygenated water) induced secondary dormancy in seeds of both species. Dormancy could be induced in 86% of meadow salsify seeds and in 65% of western salsify seeds by a 1-d anaerobiosis treatment. The induced dormancy was gradually released during storage of air-dried secondary dormant meadow salsify seeds, and the rate of this release was influenced by storage temperature; 30 C was more effective than 10 or 20 C in releasing secondary dormancy. These results suggest that the two species may rely on induced dormancy as an option in their persistence strategy. The optimum temperature for germination of nondormant seeds of both species was 15 C. Maximum germination percentages for both species were established within 4 to 6 d of incubation at 15 C and within 14 to 28 d of incubation at 25 C. Nondormant seeds did not germinate below 10 or above 30 C. Stratification (at 5 C for 2 to 10 wk) stimulated germination of secondary dormant seeds of meadow salsify. This stratification requirement can be important in preventing germination of dormant salsify seeds in the fall, thereby avoiding high seedling mortality in the winter. Light (red and far-red) had no effect on germination of seeds in secondary dormancy. In a separate study, seeds of both species were planted in pots at depths of 2 to 14 cm and seedling emergence was observed. Maximum emergence occurred when seeds were buried 2 cm deep. Seeds planted 8 cm or deeper germinated but did not emerge.
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Lycheva, N. A., A. V. Sedov, D. A. Makushkina, I. I. Shakhmatov, and V. M. Vdovin. "Accidental hypothermia as a factor of microcirculatory disorders." Kazan medical journal 100, no. 2 (December 15, 2019): 252–56. http://dx.doi.org/10.17816/kmj2019-252.
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Aim. To study the dynamics of indicators of microcirculation during a single episode of hypothermia of moderate degree in rats, both immediately after cessation of cooling, and in different periods of posthypothermia. Methods. The study was performed on 25 Wistar rats. The animals were subjected to a single immersion cooling in water at a temperature of 5 °C until reaching a rectal temperature of 27-30 °C. Analysis of the microvasculature was carried out immediately upon reaching a moderate degree of hypothermia, 2, 5, 10 and 14 days after the cooling. The microcirculation parameters were estimated using a laser analyzer of capillary circulation LAKK-02 (SMO «Lazma», Russia) at a wavelength of 0.63 μm. The main parameters of microcirculation were recorded, and the amplitude-frequency spectrum of blood flow oscillations was analyzed. Results. Immediately after reaching a moderate degree of hypothermia, vasospasm was recorded, which was confirmed by a decrease in the rate of perfusion and wave amplitudes of all frequency ranges. 2 days after stopping the cooling perfusion index returned to baseline, a decrease in amplitude of endothelial, vasomotor and respiratory waves was observed with an increase in pulse waves. On day 5, perfusion increased by 5 times was observed along with decreased amplitudes of the waves of all ranges. By day 10, the level of blood flow returned to its original values, and the wave amplitudes of all frequency ranges remained at the same low level. By day 14, a progressive decrease of the factors of bloodflow modulation was associated by the decrease of perfusion. Conclusion. Single cooling to a moderate degree of hypothermia leads to a progressive decrease of tissue perfusion and deep inhibition of active and passive factors of bloodflow modulation.
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Vasilenko, V. N., L. N. Frolova, I. V. Dragan, and N. A. Mihajlova. "Development of production extruded feed for tilapia industrial production." Proceedings of the Voronezh State University of Engineering Technologies 81, no. 1 (July 18, 2019): 132–37. http://dx.doi.org/10.20914/2310-1202-2019-1-132-137.
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As a result of the analysis of domestic experience over the past 10 years and foreign experience (on the example of 9 countries: Vietnam, India, Spain, Canada, China, Norway, the USA, Chile, Japan, which possess the most advanced technologies and equipment for the production of highly effective feed for fish ) in the development of innovative technologies and equipment for the production of highly effective feed for fish, it was found out that the methods of both dry and wet pressing are outdated and do not meet modern requirements for the production of feed for fish, as they do not allow to carry out deep physicochemical transformations in the protein-carbohydrate complex and to introduce fat components at 40% level. Modern fish technologies are based on the use of extrusion processing of a multicomponent mixture to impart different buoyancy and adjustable immersion speed of the resulting feed. Extrusion technology will allow to introduce a large amount of fat into the product - up to 35–40%, to achieve 100% starch cleavage level. Extruded product has high water resistance, keeps its shape. New generation developed compound feed formulations for tilapia with 60% protein content, 40% fat, with the introduction of growth stimulants, dietary supplements, etc., will increase the digestibility of compound feed by fish by 10-12%, increase of fish weight by 10-12%, reduce the cost of commercial fish farming by 10–15%, reduce feed conversion by 15%. The proposed technology will allow to create new generation compound feeds formulations for various fish species with a high content of protein-fat complex, which will increase the weight gain of fish by 12-17%, reduce the cost of final fish production by reducing the cost of feed by 10-15%. .
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Moura, Orilda M., Daniel A. Marinho, Jorge E. Morais, Mafalda P. Pinto, Luís B. Faíl, and Henrique P. Neiva. "Learn-to-swim program in a school context for a twelve-week period enhance aquatic skills and motor coordination in Brazilian children (Las clases de natación en el contexto escolar durante un período de doce semanas mejoran las habilidades acuáticas y l." Retos 43 (July 19, 2021): 316–24. http://dx.doi.org/10.47197/retos.v43i0.88903.
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This study aimed to verify the effects of 12 weeks of swimming lessons implemented in age school Brazilian children’s aquatic skills and motor coordination. Fifty children aged 6 to 10 years old (mean ± SD: 8.34 ± 1.10 years), participated in one swimming lesson per week provided by the school curriculum. Each child was evaluated for their aquatic skills (17 skills checklist) and motor coordination (Körperkoordinationstest Für Kinder test–KTK) before and after the swimming program. This study showed significant improvements in the sum of scores obtained in swimming skills evaluation (31.40 ± 12.89 vs. 46.90 ± 10.73 points, p < .01, d = 3.38). Large effects were found in water orientation and adjustment at the vertical position, breath control, horizontal buoyancy, body position at ventral, dorsal gliding and at longitudinal rotation, front and back somersaults, leg kicking with breath control, feet-first/head-first entries, autonomy in a deep pool and vertical buoyancy and immersion at deep water. The sum of scores in motor coordination assessment increased from 140.64 ± 41.94 to 175.20 ± 41.39 points (p < .01, d = 1.56). These results showed that 12 weeks of swimming practices, even conditioned by state school context (i.e., once a week), allowed Brazilian children aged 6-10 years old to increase aquatic skills and motor coordination.
Resumen. Este estudio tuvo como objetivo verificar los efectos de las clases de natación durante un período de 12 semanas en las habilidades acuáticas y la coordinación motora en niños brasileños. Cincuenta niños entre los 6 y los 10 años de edad (media ± DE: 8.34 ± 1.10 años) participaron una vez por semana en una clase de natación ofrecida por el plan de estudios escolar. Cada niño fue evaluado en cuanto a sus habilidades acuáticas (lista de verificación de 17 habilidades) y coordinación motora (Körperkoordinationstest Für Kinder test - KTK) antes y después del programa de natación. Los resultados del estudio mostraron mejoras significativas en la suma de las puntuaciones obtenidas en la evaluación de las habilidades de natación (31.40 ± 12.89 frente a 46.90 ± 10.73 puntos, p < .01, d = 3.38). Se observaran efectos importantes en la orientación y el ajuste del agua en la posición vertical, en el control de la respiración, en la flotabilidad horizontal, en la posición del cuerpo en la posición ventral, en el deslizamiento dorsal y la rotación longitudinal, en los saltos mortales hacia adelante y hacia atrás, en los empujes con las piernas con control de la respiración, pies primero / cabeza primero entradas, en la autonomía en piscina profunda y flotabilidad vertical y inmersión en aguas profundas. La suma de las puntuaciones en la evaluación de la coordinación motora aumentó de 140.64 ± 41.94 a 175.20 ± 41.39 puntos (p < .01, d = 1.56). Estos resultados mostraron que 12 semanas de prácticas de natación, incluso condicionadas por el contexto de la escuela estatal (es decir, una vez por semana), permitieron a los niños brasileños de 6 a 10 años aumentar de forma significativa la preparación acuática y la coordinación motora.