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Cooling
Kinds of Cooling Terms modified by Cooling Selected AbstractsLIVE-BIRTH IN VIPERS (VIPERIDAE) IS A KEY INNOVATION AND ADAPTATION TO GLOBAL COOLING DURING THE CENOZOICEVOLUTION, Issue 9 2009Vincent J. Lynch The identification of adaptations and key innovations has long interested biologists because they confer on organisms the ability to exploit previously unavailable ecological resources and respond to novel selective pressures. Although it can be extremely difficult to test for the effects of a character on the rate of lineage diversification, the convergent evolution of a character in multiple lineages provides an excellent opportunity to test for the effect of that character on lineage diversification. Here, I examine the effect of parity mode on the diversification of vipers, which have independently evolved viviparity in at least 13 lineages. I find strong statistical evidence that viviparous species diversify at a greater rate than oviparous species and correlate major decreases in the diversification rate of oviparous species with periods of global cooling, such as the Oligocene. These results suggest that the evolution of viviparity buffered live-bearing species against the negative effects of global climate change during the Cenozoic, and was a key innovation in the evolution and diversification of live-bearing vipers. [source] CHARACTERISTICS OF CHAMBER TEMPERATURE CHANGE DURING VACUUM COOLINGJOURNAL OF FOOD PROCESS ENGINEERING, Issue 2 2009RUI ZHAO ABSTRACT In order to investigate the dynamic changing pattern of the chamber temperature with chamber pressure during vacuum cooling, 10 repeated experiments were conducted to evaluate the time-dependent temperature and pressure in the vacuum chamber during vacuum cooling of water. Water was chosen in the experiment as it is the main component of most foods. The results showed that the temperature in the vacuum chamber significantly depended on variation in pressure at different pumping stages. The temperature changes in the chamber generally followed a certain pattern. In the early stage of vacuum cooling, the chamber temperature dropped very quickly (0.26 K/s), while at the end of vacuum cooling, it increased rapidly (0.22 K/s), and was about 11.8 K higher than the ambient temperature when the vacuum was released with ambient air flowing back to the chamber. PRACTICAL APPLICATIONS Vacuum cooling is a rapid cooling method for the food industry; further understanding of the vacuum cooling mechanism can help to control and improve this cooling process. Temperature changing pattern and distribution affects the quality of the food product in vacuum cooling process. As the main component of most foods is water, it is necessary to investigate the dynamic temperature changing pattern and distribution with vacuum pressure during vacuum cooling of water so that the information obtained could be used as a reference for vacuum cooling of food products. [source] EFFECT OF RAPID COOLING ON THE GROWTH AND PENETRATION OF SALMONELLA ENTERITIDIS INTO EGG CONTENTSJOURNAL OF FOOD SAFETY, Issue 4 2002HAIQIANG CHEN ABSTRACT Shell eggs were inoculated internally with approximately 10 cells of Salmonella enterica serovar enteritidis (S. enteritidis) and subjected to three different cooling treatments. Eggs were cooled from an initial temperature of 27C to approximately 7.2C. After cooling, eggs were stored at approximately 7.2C for 36 days, or stored at 5.7,9.5C for 30 days plus 6 days at 37C to simulate temperature abuse. Rapid cooling and subsequent storage of eggs at approximately 7.2C inhibited the growth of S. enteritidis in eggs. Slow cooling, and/or temperature abuse promoted growth of S. enteritidis in eggs. The penetration study indicated that rapid cooling and subsequent storage at 7.2C for 30 days did not affect the penetration of S. enteritidis into egg contents. The S. enteritidis isolated from the eggshell with shell membranes was significantly higher (P < 0.05) than from the internal egg contents, indicating that most of the S. enteritidis cells were trapped within the shell pores and/or shell membranes. [source] Simulation Study of Radiative Cooling in the Divertor on JT-60 Super Advanced (JT-60SA)CONTRIBUTIONS TO PLASMA PHYSICS, Issue 1-3 2008Y. Suzuki Abstract A simulation study of the divertor for JT-60SA is discussed in both double-null (DN) and single-null (SN) configurations. In the DN case, the transition of peak heat load on the targets and divertor plasma states from CDN (connected double-null) to DDN (disconnected double-null) are shown in the simulation. The radiative cooling power in the divertor plasma is discussed in this study. The carbon impurity generated by the sputtering on the divertor target is included in the simulation. In the gas puffing cases of fueling gas (D2) and impurity gas (Ne), the reduction of heat load is confirmed consistently with increasing the radiative cooling loss power in the diverter plasma. The loss power and the distribution of radiative cooling in the divertor plasma are studied in this paper. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Outcomes of Childhood Hemangiomas Treated with the Pulsed-Dye Laser with Dynamic Cooling: A Retrospective Chart AnalysisDERMATOLOGIC SURGERY, Issue 12 2009CARINA RIZZO MD BACKGROUND Laser treatment of childhood hemangiomas remains controversial. Previous studies have used outdated technology, resulting in a potential overrepresentation of adverse outcomes. OBJECTIVE To evaluate outcomes of hemangiomas treated with the most current laser technology. METHODS A retrospective chart analysis of 90 patients with a median age of 3.0 months and a total of 105 hemangiomas were enrolled over a 2.5-year period. All were treated with the 595-nm long-pulse pulsed-dye laser (LP-PDL) with dynamic epidermal cooling at 2- to 8-week intervals depending on the stage of growth. Exclusion criteria were previous laser, surgical, or corticosteroid treatment. Three reviewers assessed outcomes. RESULTS Near-complete or complete clearance in color were achieved for 85 (81%) and in thickness for 67 (64%) hemangiomas. There was no scarring or atrophy. Ulceration occurred in one case and resolved during treatment. Hyperpigmentation and hypopigmentation occurred in 4% and 14% of hemangiomas, respectively. CONCLUSION Early treatment of childhood hemangiomas with the 595-nm LP-PDL with dynamic cooling may reduce the proliferative phase and result in excellent rates of clearing and few adverse events. [source] Treatment of Port-Wine Stain Birthmarks Using the 1.5-msec Pulsed Dye Laser at High Fluences in Conjunction with Cryogen Spray CoolingDERMATOLOGIC SURGERY, Issue 4 2002Kristen M. Kelly MD Background. The majority of port-wine stain (PWS) patients treated with the pulsed dye laser (PDL) do not achieve complete blanching. Safe administration of higher fluences has been proposed as a means of improving treatment efficacy. Objective. To determine the safety and efficacy of PWS treatment with the 1.5-msec PDL at high fluences in conjunction with cryogen spray cooling. Methods. Twenty PWS patients were treated with the PDL in combination with cryogen spray cooling utilizing a 7 or 10 mm spot size and fluences ranging from 6 to 15 J/cm2. Before and after treatment photographs were compared on a blinded basis. Results. No scarring or skin textural changes occurred. Blanching scores were as follows: 20% of patients achieved 75% or greater blanching after an average of 3.3 treatments, 30% achieved 50,74% blanching, 20% achieved 25,49% blanching, and 30% achieved less than 25% blanching. Conclusion. In conjunction with cryogen spray cooling, the PDL can be safely used at high fluences. At this time it is not clear that the use of higher fluences improves treatment efficacy; however, as other aspects of PWS laser treatment are optimized, safe administration of higher fluences is likely to be advantageous. [source] Foot temperature in diabetic polyneuropathy: innocent bystander or unrecognized accomplice?DIABETIC MEDICINE, Issue 3 2005S. B. Rutkove Abstract Aim To explore mechanisms by which temperature could influence the pathogenesis and symptoms of diabetic polyneuropathy. Methods We conducted a literature review attempting to identify mechanisms by which diabetic polyneuropathy could be affected by temperature. Results Cooling can theoretically hasten the progression of diabetic polyneuropathy through several different mechanisms. Specifically, cooling can enhance neuronal ischaemia, increase formation of reactive oxygen species, slow axonal transport, increase protein kinase C activity, and interfere with immune function. Short-term temperature fluctuations (both warming and cooling) can initiate and exacerbate neuropathic pain by causing neuronal hyperexcitability and functional deafferentation. Although normal fluctuations of distal extremity temperature may be sufficient for these effects, impaired thermoregulation may make the distal extremities more susceptible to temperature extremes. Eventually, a ,vicious cycle' may ensue, resulting in neuronal deterioration with further disruption of temperature regulation. Limited epidemiological data suggest a higher prevalence of diabetic polyneuropathy in populations living in colder locations, supporting our hypothesis. Conclusions Variations in foot temperature may play an important but as yet unrecognized role in the development and symptoms of diabetic polyneuropathy. Further basic and clinical research exploring this concept could help elucidate the natural history of diabetic polyneuropathy and lead to novel therapeutic strategies. [source] Cooling Abolishes Neuronal Network Synchronization in Rat Hippocampal SlicesEPILEPSIA, Issue 6 2002Sam P. Javedan Summary: ,Purpose: We sought to determine whether cooling brain tissue from 34 to 21°C could abolish tetany-induced neuronal network synchronization (gamma oscillations) without blocking normal synaptic transmission. Methods: Intracellular and extracellular electrodes recorded activity in transverse hippocampal slices (450,500 ,m) from Sprague,Dawley male rats, maintained in an air,fluid interface chamber. Gamma oscillations were evoked by afferent stimulation at 100 Hz for 200 ms. Baseline temperature in the recording chamber was 34°C, reduced to 21°C within 20 min. Results: Suprathreshold tetanic stimuli evoked membrane potential oscillations in the 40-Hz frequency range (n = 21). Gamma oscillations induced by tetanic stimulation were blocked by bicuculline, a ,-aminobutyric acid (GABA)A -receptor antagonist. Cooling from 34 to 21°C reversibly abolished gamma oscillations in all slices tested. Short, low-frequency discharges persisted after cooling in six of 14 slices. Single-pulse,evoked potentials, however, were preserved after cooling in all cases. Latency between stimulus and onset of gamma oscillation was increased with cooling. Frequency of oscillation was correlated with chamber cooling temperature (r = 0.77). Tetanic stimulation at high intensity elicited not only gamma oscillation, but also epileptiform bursts. Cooling dramatically attenuated gamma oscillation and abolished epileptiform bursts in a reversible manner. Conclusions: Tetany-induced neuronal network synchronization by GABAA -sensitive gamma oscillations is abolished reversibly by cooling to temperatures that do not block excitatory synaptic transmission. Cooling also suppresses transition from gamma oscillation to ictal bursting at higher stimulus intensities. These findings suggest that cooling may disrupt network synchrony necessary for epileptiform activity. [source] Rapid Cooling Aborts Seizure-Like Activity in Rodent Hippocampal-Entorhinal SlicesEPILEPSIA, Issue 10 2000Matthew W. Hill Summary Purpose: As a preliminary step in the development of an implantable Peltier device to abort focal neocortical seizures in vivo, we have examined the effect of rapid cooling on seizures in rodent hippocampal-entorhinal slices. Methods: Seizure-like discharges were induced by exposing the slices to extracellular saline containing 4-aminopyridine (50 ,mol/L). Results: When we manually activated a Peltier device that was in direct contact with the slice, seizures terminated within seconds of the onset of cooling, sometimes preceding a detectable decrease in temperature measured near the top of the slice. However, activation of the Peltier device did not stop seizures when slices were no longer in direct physical contact with the device, indicating that this was not a field effect. When cooling was shut off and temperature returned to 33oC, bursting some-times returned, but a longer-term suppressive effect on seizure activity could be observed. In two of our experiments, a custom computer program automatically detected seizure discharges and triggered a transistor-transistor logic pulse to activate the Peltier device. In these experiments, the Peltier device automatically terminated the slice bursting in less than 4 seconds. When the Peltier device was placed in contact with the normal, exposed cortex of a newborn pig, we found that the cortical temperature decreased rapidly from 36oC to as low as 26oC at a depth of 1.7 mm below the cooling unit. Conclusions: These experiments show that local cooling may rapidly terminate focal paroxysmal discharges and might be adapted for clinical practice. [source] Role of the nitric oxide on diazoxide-induced relaxation of the calf cardiac vein and coronary artery during coolingFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 3 2009K. E. Atalik Abstract The effects of cooling (to 28 °C) on the vasodilation induced by diazoxide (10,9,3 × 10,4 m) on carbachol-pre-contracted calf cardiac vein and coronary artery and the role of nitric oxide in these effects were analyzed. Diazoxide produced concentration-dependent relaxation of calf cardiac vein and coronary artery rings pre-contracted with carbachol (10,6 m). During cooling, the pIC50 values, but not the maximal responses, to diazoxide were significantly lower than at 37 °C in both preparations. Cooling to 28 °C in the presence of NG -nitro-L-arginine methyl ester (10,4 m) did not modify the effect of temperature both in cardiac vein and coronary artery. These results suggest that cooling-induced changes of diazoxide in calf cardiac vein and coronary artery are independent of nitric oxide. [source] Surface Cooling for Rapid Induction of Mild Hypothermia After Cardiac Arrest: Design Determines EfficacyACADEMIC EMERGENCY MEDICINE, Issue 4 2010Thomas Uray MD Abstract Objectives:, Recently, a novel cooling pad was developed for rapid induction of mild hypothermia after cardiac arrest. The aim of this study was to evaluate the cooling efficacy of three different pad designs for in-hospital cooling. Methods:, Included in this prospective interventional study were patients with esophageal temperature (Tes) > 34°C on admission. The cooling pad consists of multiple cooling units, filled with a combination of graphite and water, which is precooled to ,18°C (design A) or to ,9°C (designs B and C) before use. The designs of the cooling pad differed in number, shape, and thickness of the cooling units, with weights of 9.7 kg (design A), 5.3 kg (design B), and 6.2 kg (design C). All three designs were tested in sequential order and were changed according to the results found in the previous trial. Cooling was started after admission until Tes = 34°C, when the cooling pad was removed. The target temperature of Tes = 32,34°C was maintained for 24 hours. Data are presented as medians and interquartile ranges (IQRs = 25%,75%) or proportions. Results:, Cooling rates were 3.4°C/hour (IQR = 2.5,3.7) with design A (n = 12), 2.8°C/hour (IQR = 1.6,3.3) with design B (n = 7), and 2.9°C/hour (IQR = 1.9,3.6) with design C (n = 10; p = 0.5). To reach 34°C, the cooling pad had to be exchanged with a new one due to melting and therefore depleting cooling capacity in three patients with design A, in five patients with design B, and in no patient with design C (p = 0.004). Conclusions:, With adequate design and storage temperature, the cooling pad proved to be efficient for rapid in-hospital cooling of patients resuscitated from cardiac arrest. ACADEMIC EMERGENCY MEDICINE 2010; 17:360,367 © 2010 by the Society for Academic Emergency Medicine [source] Precipitation of lead,zinc ores in the Mississippi Valley-type deposit at Trèves, Cévennes region of southern FranceGEOFLUIDS (ELECTRONIC), Issue 1 2006D. LEACH Abstract The Trèves zinc,lead deposit is one of several Mississippi Valley-type (MVT) deposits in the Cévennes region of southern France. Fluid inclusion studies show that the ore was deposited at temperatures between approximately 80 and 150°C from a brine that derived its salinity mainly from the evaporation of seawater past halite saturation. Lead isotope studies suggest that the metals were extracted from local basement rocks. Sulfur isotope data and studies of organic matter indicate that the reduced sulfur in the ores was derived from the reduction of Mesozoic marine sulfate by thermochemical sulfate reduction or bacterially mediated processes at a different time or place from ore deposition. The large range of ,34S values determined for the minerals in the deposit (12.2,19.2, for barite, 3.8,13.8, for sphalerite and galena, and 8.7 to ,21.2, for pyrite), are best explained by the mixing of fluids containing different sources of sulfur. Geochemical reaction path calculations, based on quantitative fluid inclusion data and constrained by field observations, were used to evaluate possible precipitation mechanisms. The most important precipitation mechanism was probably the mixing of fluids containing different metal and reduced sulfur contents. Cooling, dilution, and changes in pH of the ore fluid probably played a minor role in the precipitation of ores. The optimum results that produced the most metal sulfide deposition with the least amount of fluid was the mixing of a fluid containing low amounts of reduced sulfur with a sulfur-rich, metal poor fluid. In this scenario, large amounts of sphalerite and galena are precipitated, together with smaller quantities of pyrite precipitated and dolomite dissolved. The relative amounts of metal precipitated and dolomite dissolved in this scenario agree with field observations that show only minor dolomite dissolution during ore deposition. The modeling results demonstrate the important control of the reduced sulfur concentration on the Zn and Pb transport capacity of the ore fluid and the volumes of fluid required to form the deposit. The studies of the Trèves ores provide insights into the ore-forming processes of a typical MVT deposit in the Cévennes region. However, the extent to which these processes can be extrapolated to other MVT deposits in the Cévennes region is problematic. Nevertheless, the evidence for the extensive migration of fluids in the basement and sedimentary cover rocks in the Cévennes region suggests that the ore forming processes for the Trèves deposit must be considered equally viable possibilities for the numerous fault-controlled and mineralogically similar MVT deposits in the Cévennes region. [source] The Association Between Hypothermia, Prehospital Cooling, and Mortality in Burn VictimsACADEMIC EMERGENCY MEDICINE, Issue 4 2010Adam J. Singer MD Abstract Objectives:, Hypothermia is associated with increased morbidity and mortality in trauma victims. The prognostic value of hypothermia on emergency department (ED) presentation in burn victims is not well known. The objective of this study was to determine the incidence of hypothermia in burn victims and its association with mortality and hospital length of stay (LOS). The study also examined the potential causative role of prehospital cooling in hypothermic burn patients. Methods:, This was a retrospective review of a county trauma registry. The county was both suburban and rural, with a population of 1.5 million and with one burn center. Burn patients between 1994 and 2007 who met trauma registry criteria were included. Demographic and clinical data including prehospital cooling, burn size and depth, and presence of inhalation injury were collected. Hypothermia was defined as a core body temperature of less than or equal to 35°C. Data analysis consisted of univariate associations between patient characteristics and hypothermia. Results:, There were 1,215 burn patients from 1994 to 2007. Mean age (±standard deviation [±SD]) was 29 (±24) years, 67% were male, 248 (26.7%) had full-thickness burns, and 24 (2.6%) had inhalation injury. Only 17 (1.8%) had a burn larger than 70% total body surface area (TBSA). A total of 929 (76%) patients had an initial ED temperature recorded. Only 15/929 (1.6%) burn patients had hypothermia on arrival, and all were mild (lowest temperature was 32.6°C). There was no association between sex, year, and presence of inhalation injury with hypothermia. Hypothermic patients were older (44 years vs. 29 years, p = 0.01), and median Injury Severity Score (ISS) was higher (25 vs. 4, p = 0.002) than for nonhypothermic patients. Hypothermia was present in 6/17 (35%) patients with a TBSA of 70% or greater and in 8/869 (0.9%) patients with a TBSA of <70% (p < 0.001). Mortality was higher in hypothermic patients (60% vs. 3%, p < 0.001). None of the hypothermic patients received prehospital cooling. Conclusions:, Hypothermia on presentation to the ED was noted in 1.6% of all burn victims in this trauma registry. Hypothermia was more common in very large burns and was associated with high mortality. In this series, prehospital cooling did not appear to contribute to hypothermia. ACADEMIC EMERGENCY MEDICINE 2010; 17:456,459 © 2010 by the Society for Academic Emergency Medicine [source] Cooling and inferred exhumation history of the Ryoke metamorphic belt in the Yanai district, south-west Japan: Constraints from Rb,Sr and fission-track ages of gneissose granitoid and numerical modelingISLAND ARC, Issue 2 2001Takamoto Okudaira Abstract The Ryoke metamorphic belt in south-west Japan consists mainly of I-type granitoids and associated low-pressure/high-temperature metamorphic rocks. In the Yanai district, it has been divided into three structural units: northern, central and southern units. In this study, we measured the Rb,Sr whole-rock,mineral isochron ages and fission-track ages of the gneissose granodiorite in the central structural unit. Four Rb,Sr ages fall in a range of ca 89,87 Ma. The fission-track ages of zircon and apatite are 68.9 ± 2.6 Ma and 57.4 ± 2.5 Ma (1, error), respectively. Combining the newly obtained ages with previously reported (Th,)U,Pb ages from the same unit, thermochronologic study revealed two distinctive cooling stages; 1) a rapid cooling (> 40°C/Myr) for a period (~7 Myr) soon after the peak metamorphism (~ 95 Ma) and 2) the subsequent slow cooling stage (~ 5°C/Myr) after ca 88 Ma. The first rapid cooling stage corresponds to thermal relaxation of the intruded granodiorite magma and its associated metamorphic rocks, and to the uplift by a displacement along low-angle faults which initiated soon after the intrusion of the magma. Uplift by the later stage deformation having formed large-scale upright folds resulted in progress of the exhumation during the first stage. The average exhumation velocity of the stage is , 2 mm/yr. During the second stage, the rocks were not accompanied by ductile deformation and were exhumed with the rate of 0.1,0.2 mm/yr. The difference in the exhumation velocity between the first and second cooling stages resulted from the difference in the thickness of the crust and in the activity of ductile deformation between the early and later stages of the orogenesis. [source] Effects of Fat on Temporal Cooling by Menthol in LozengesJOURNAL OF FOOD SCIENCE, Issue 8 2001A-M.A. Allison ABSTRACT: Ingredients such as fat may suppress or enhance menthol cooling in a finished product. In this study, trained descriptive sensory panelists tested oral and nasal cooling, oral burn, and other attributes in lozenges with various concentrations of fat (0 to 5%) and menthol (0 to 0.4%). Increasing fat content reduced oral and nasal cooling and burn. Linear increases in menthol resulted in linear responses to nasal cooling and oral burn and nonlinear responses to oral cooling. Residual oral and nasal cooling and burn illustrated that the effect of fat became less important after the lozenge was expectorated. [source] Clinical utility of dorsal sural nerve conduction studiesMUSCLE AND NERVE, Issue 6 2001James M. Killian MD Abstract A technique of testing sensory nerve conduction of the dorsal sural nerve in the foot was used in 38 normal subjects and 70 patients with peripheral neuropathies. The normal dorsal sural sensory nerve action potential (SNAP) had a mean amplitude of 8.9 ,V (range 5,15 ,V), mean latency to negative peak of 4.0 ms (range 3.2,4.7 ms), and mean conduction velocity of 34.8 m/s (range 30,44 m/s). Optimal placement of the recording electrodes to obtain a maximal nerve action potential was proximal to digits 4 and 5. Cooling to below 25°C prolonged the latency but did not decrease the SNAP amplitude. Among the patients with peripheral neuropathy, dorsal sural SNAP was absent in 68 (97%), whereas only 54 (77%) showed abnormalities of sural sensory conduction. The diagnostic sensitivity of sensory nerve conduction studies in peripheral neuropathies may be significantly improved by the use of this technique for evaluating the action potential of the dorsal sural nerve. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 817,820, 2001 [source] Limiting Global Cooling after Global Warming is Over , Differentiating Between Short- and Long-Lived Greenhouse GasesOPEC ENERGY REVIEW, Issue 4 2003Axel Michaelowa Current climate policy does not take into account that, after greenhouse gas emissions have been reduced to an extent that atmospheric concentrations stabilise and then start to fall, natural decay of greenhouse gases will lead to a global cooling phase spanning several centuries. This cooling will lead to damage to humans and ecosystems that depends on the rate of temperature change. Current climate policy should thus concentrate on the reduction of short- and medium-lived greenhouse gases, while exempting long-lived gases. This reduces the cooling rate. Another policy option is to sequester carbon in geological reservoirs that allow controlled release in the future. [source] Reduction of Oxidative Stress in Bovine Spermatozoa During Flow Cytometric SortingREPRODUCTION IN DOMESTIC ANIMALS, Issue 1 2007P Klinc Contents The goal of the study was to investigate the effect of antioxidant supplementation on the quality of frozen-thawed flow cytometrically sorted bull spermatozoa. Twelve ejaculates from two Holstein Friesian bulls were sorted according to the Beltsville Sperm Sexing Technology. Each ejaculate was divided into three parts and processed as (i) unsorted controls, (ii) according to a standard sorting protocol and (iii) in the presence of different antioxidants (S-AO). Cooling and freezing of the samples were performed in the same way for all three groups, except that antioxidants were added to the TRIS-egg-yolk freezing extender for those semen samples that were already sorted in the presence of antioxidants. The semen quality in frozen-thawed samples was determined by morphology analysis immediately after thawing, motility estimation in a thermo-resistance test after 0, 6, 12 and 24 h incubation at 37°C and Fluorescein isothiocyanate conjugated PNA/propidium iodide (FITC-PNA/PI) staining after 0, 12 and 24 h of incubation at 37°C. There was a significantly higher (p < 0.05) percentage of motile spermatozoa in S-AO samples in comparison to unsorted frozen-thawed control at 0, 6 and 24 h after thawing and compared with normally sorted samples at all times after thawing. The percentage of damaged acrosomes was significantly lower (p < 0.05) in S-AO samples than in the unsorted controls (20.8 ± 6.9% vs 30.3 ± 12.0%). The percentage of morphologically abnormal spermatozoa in this group was significantly lower (p < 0.05) than in the unsorted controls and normally sorted samples (25.8 ± 5.2%, 36.0 ± 12.5% and 35.1 ± 7.4%, respectively). Analysis of frozen-thawed spermatozoa with FITC/PI revealed no significant difference in membrane integrity at 0 and 12 h after sorting, but after 24 h of incubation the S-AO samples had a significantly higher (p < 0.001) percentage of spermatozoa with intact membranes in comparison to unsorted controls and normally sorted semen (40.7 ± 6.3%, 7.8 ± 4.7% and 7.4 ± 4.6%, respectively). The percentage of acrosome-reacted spermatozoa was significantly lower (p < 0.05) in the S-AO samples than in the unsorted controls (14.1 ± 7.5%, 23.4 ± 5.4% and 28.8 ± 6.3% vs 25.9 ± 14.4%, 38.5 ± 16.7% and 79.8 ± 4.1%, for 0, 12 and 24 h after thawing, respectively) and in comparison to normally sorted semen 24 h after thawing (67.3 ± 10.0%). This study demonstrates the highly protective effects of antioxidants on the quality of flow cytometrically sorted frozen-thawed bull spermatozoa. [source] Transient Cooling of Heat-Generating Materials with Thermoelectric CoolersCHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 6 2006Y. Makino Abstract The transient cooling of heat-generating materials contacted with a thermoelectric microcooler was discussed, and the operation of a fixed electric current was proposed as an alternative to the conventional operation of a variable electric current to obtain the maximum heat flux of cooling. The changes in temperature of the materials cooled by the thermoelectric cooler were obtained by numerical calculation of the unsteady one-dimensional energy equation. The proposed operation of a fixed current was found to be a useful alternative to the conventional operation. An approximate analysis was made on the basis of the results of the numerical calculation. The results showed that the transient response of cooling of material without heat generation could be expressed by the first-order delay. Comparisons with the numerical calculation indicated that the expression by the first-order delay is also applicable to the cooling of material with heat generation and that the time constant decreases with increasing rate of heat generation from the material. [source] Application of Visual Analytics for Thermal State Management in Large Data CentresCOMPUTER GRAPHICS FORUM, Issue 6 2010M. C. Hao I.3.3 [Computer Graphics]: Picture/Image Generation,Display Algorithms; H.5.0 [Information Systems]: Information Interfaces and Presentation,General Abstract Today's large data centres are the computational hubs of the next generation of IT services. With the advent of dynamic smart cooling and rack level sensing, the need for visual data exploration is growing. If administrators know the rack level thermal state changes and catch problems in real time, energy consumption can be greatly reduced. In this paper, we apply a cell-based spatio-temporal overall view with high-resolution time series to simultaneously analyze complex thermal state changes over time across hundreds of racks. We employ cell-based visualization techniques for trouble shooting and abnormal state detection. These techniques are based on the detection of sensor temperature relations and events to help identify the root causes of problems. In order to optimize the data centre cooling system performance, we derive new non-overlapped scatter plots to visualize the correlations between the temperatures and chiller utilization. All these techniques have been used successfully to monitor various time-critical thermal states in real-world large-scale production data centres and to derive cooling policies. We are starting to embed these visualization techniques into a handheld device to add mobile monitoring capability. [source] A new temperature-sensitive contrast mechanism for MRI: Curie temperature transition-based imagingCONTRAST MEDIA & MOLECULAR IMAGING, Issue 1 2007F. Settecase Abstract A temperature-sensitive MRI contrast mechanism is proposed based on the physical property, the Curie temperature (Tc), at which a ferromagnetic material transitions to paramagnetic state and vice versa. To evaluate the feasibility of this new contrast mechanism, experiments were performed with solid gadolinium metal, which has a Tc of 20°C. In phantom and ex vivo experiments, the magnetic susceptibility artifact area decreased with increasing temperature transitioning across Tc (p,<,0.05). Similar results would be expected for a variety of ferromagnetic substances with substance-specific Tc values. Temperature-sensitive MRI contrast agents harnessing this mechanism may be used to (1) indicate regional attainment of specific temperatures in thermotherapy, (2) render an accumulated contrast agent more or less visible by the external application of appropriate heating or cooling, or (3) quantify tissue temperature based on MR image characteristics and magnetic susceptibility artifact caused by a ferromagnetic,paramagnetic transitioning substance. Copyright © 2007 John Wiley & Sons, Ltd. [source] Magnetohydrodynamic Simulation of Tungsten Wire in Wire-Array Z PinchCONTRIBUTIONS TO PLASMA PHYSICS, Issue 2 2010D.-K. Kim Abstract The magnetohydrodynamic behavior of tungsten wire ablating in wire-array Z pinch discharge on MAGPIE is simulated in a two-dimensional fine-grid domain using the GORGON code. A nonideal resistivity model has been implemented in the simulation to obtain plasma transport coefficients in the high density regime along with a screened hydrogenic model to calculate the radiative cooling. Starting from the initial state of warm dense plasma, the evolution of ablated wire is demonstrated to show its explosion and implosion dynamics as a function of discharge time and then the computed profile of electron density is compared with the contour lines reproduced from the measurement by a laser interferometer during the early stage of discharge. The comparison overall shows a fair agreement in terms of the magnitude and the profile shape while some discrepancies can be attributed to the simplified description of the internal wire core physics (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] 3D Edge Transport Studies with EMC3-EIRENE for the Dynamic Ergodic Divertor (DED) at TEXTORCONTRIBUTIONS TO PLASMA PHYSICS, Issue 1-3 2008D. Harting Abstract In this paper we introduce some model extensions to the energy balances of the 3D fluid Monte-Carlo code EMC3 and study their influence on the simulation results for TEXTOR-DED. We implemented local kinetic corrections to the classical parallel heat conductivity of electrons (heat flux limit). Depending on the DED configuration, a cooling effect in the outermost SOL region, resulting from the heat flux limit, can be observed. In addition, also the adiabatic cooling term mnV2, which was neglected before, was implemented into the energy iterations. This term causes a localized cooling of the ions in front of the wall, where the plasma is accelerated towards the first wall. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Application of High Current and Current Zero Simulations of High-Voltage Circuit BreakersCONTRIBUTIONS TO PLASMA PHYSICS, Issue 10 2006C. M. Franck Abstract This paper reports on the use of computational fluid dynamic (CFD) simulations to predict the interruption behaviour of high-voltage circuit breakers (HV-CB) using the self-blast principle. Two different levels of accuracy of the arc model are proven to be sufficiently accurate for simulating the high-current phase and the period around current zero (CZ). For the high-current phase, a simplified equivalent model of the arc is implemented to predict the pressure build-up, and even more important to accurately trace the hot gas from the arcing zone into the exhausts and the heating volume. A detailed analysis of the gas mixing in the heating volume for different arcing times and current amplitudes showed the optimum geometrical design of the heating volume. For the CZ phase, a more detailed arc model is needed including the effects of ohmic heating, radiative energy transfer, and turbulent cooling fully resolved in space and time. The validation with experiments was done and shows good agreement which justifies the use of the implemented model. With it, scaling laws varying only one parameter at a time (pressure and applied current slope) were derived and confirm previously found empirical laws. This is of particular interest, as it is very difficult to derive such scaling laws from experiments where the scatter is always very large and where it is impossible to vary only one parameter at a time. The influence of the most important geometrical parameters of the nozzle on the interruption performance is shown. In addition to previous experimental indications of this, the simulation reveals that turbulent cooling on the arc edge is the main reason for the difference in interruption performance. Moreover, the exact spatio-temporal build-up of arc resistance and with it the detailed understanding of the arc interruption process is possible and shown here for the first time. These simulations enable us to predict HV-CB performance and to minimise the number of development tests and are routinely used in new development projects. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] A chilly breeze leads to heavy breathing , facial cooling and the human peripheral chemoreflexACTA PHYSIOLOGICA, Issue 2 2008A. William SheelArticle first published online: 5 SEP 200 No abstract is available for this article. [source] Nucleation kinetics and growth of nonlinear optical bis (dimethyl sulfoxide) manganese mercury thiocyanate single crystalsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 10 2008C. M. Raghavan Abstract Nonlinear optical (NLO) material of bis (dimethyl sulfoxide) manganese mercury thiocyanate (MMTD) was synthesized by two step reaction method. The solubility and metastable zonewidth were experimentally determined in order to optimize the growth parameters. Bulk crystals of MMTD were grown by slow cooling and slow evaporation methods. The structure of the grown crystal was confirmed by X-ray diffraction analysis. Presence of functional groups and the coordination of Lewis base ligand of dimethyl sulfoxide (DMSO) were confirmed by FT-IR analysis. Optical transparency of the grown crystals was studied by UV-Vis spectroscopy. Nonlinear optical property of the grown crystal was confirmed by Kurtz powder method. Etching studies reveal the formation of triangular hillock etch patterns, indicative of 2D nucleation mechanism. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Severe periodontal damage by an ultrasonic endodontic device: a case reportDENTAL TRAUMATOLOGY, Issue 2 2007John D. Walters Abstract,,, Heat produced within a root canal during use of an ultrasonic instrument can be conducted through the dentin into periodontal ligament, bone and soft tissue. If severe in intensity or long in duration, it can induce damage to these tissues. This report describes a case in which an ultrasonic endodontic instrument apparently induced severe damage to alveolar bone, gingiva and nasal mucosa in a 42-year-old female. Overheating of a maxillary central incisor caused necrosis of soft tissue and bone on the facial and mesial aspects and triggered a protracted inflammatory response in the adjacent nasal cavity. To relieve the severe discomfort associated with this damage, the patient chose to have her maxillary incisors extracted and replaced by a removable partial denture. A defect in the soft tissue and bone was present at a follow-up visit 10 months after the extractions. While morbidity of this nature is rare, this case reinforces the need to maintain adequate cooling of ultrasonic instruments. [source] Outcomes of Childhood Hemangiomas Treated with the Pulsed-Dye Laser with Dynamic Cooling: A Retrospective Chart AnalysisDERMATOLOGIC SURGERY, Issue 12 2009CARINA RIZZO MD BACKGROUND Laser treatment of childhood hemangiomas remains controversial. Previous studies have used outdated technology, resulting in a potential overrepresentation of adverse outcomes. OBJECTIVE To evaluate outcomes of hemangiomas treated with the most current laser technology. METHODS A retrospective chart analysis of 90 patients with a median age of 3.0 months and a total of 105 hemangiomas were enrolled over a 2.5-year period. All were treated with the 595-nm long-pulse pulsed-dye laser (LP-PDL) with dynamic epidermal cooling at 2- to 8-week intervals depending on the stage of growth. Exclusion criteria were previous laser, surgical, or corticosteroid treatment. Three reviewers assessed outcomes. RESULTS Near-complete or complete clearance in color were achieved for 85 (81%) and in thickness for 67 (64%) hemangiomas. There was no scarring or atrophy. Ulceration occurred in one case and resolved during treatment. Hyperpigmentation and hypopigmentation occurred in 4% and 14% of hemangiomas, respectively. CONCLUSION Early treatment of childhood hemangiomas with the 595-nm LP-PDL with dynamic cooling may reduce the proliferative phase and result in excellent rates of clearing and few adverse events. [source] Variable-Pulse Nd:YAG Laser in the Treatment of Facial TelangiectasiasDERMATOLOGIC SURGERY, Issue 1 2006AVERY A. BEVIN MD BACKGROUND Variable-pulse 1,064 nm wavelength lasers have been used with good effectiveness on leg telangiectasias and reticular veins and have shown promising results on facial telangiectasias as well. OBJECTIVE To investigate the effectiveness of a variable-pulse neodymium:yttrium-aluminum-garnet (Nd:YAG) laser using a small spot size in the treatment of facial telangi-ectasias. METHODS Eight male patients (mean age 75 years) underwent a single treatment session using a variable-pulse 1.5 mm spot size Nd:YAG laser with epidermal cooling. Telangiectasia diameters were 0.3 to 2.0 mm. Test sites were performed using three pulse widths (3, 20, and 60 ms), with fluences varying depending on vessel size and response. Full treatments were per-formed using test parameters giving the best response. Thirteen weeks later, the patients returned for final evaluation and satisfaction rating. RESULTS Fluences ranged from 226 to 425 J/cm2, with smaller vessels requiring larger energies. Pulse duration was equally divided between the 20 and 60 ms settings. The shortest pulse width (3 ms) was inferior in all patients. Longer pulse durations achieved superior vessel elimination with minimal immediate purpura and no postinammatory hyperpigmentation. The average mean vessel clearance was 26 to 50% in half of the patients and 51 to 75% in the other half as evaluated by three unbiased dermatologists with extensive laser experience. CONCLUSION A small,spot size Nd:YAG laser using a pulse width of 20 ms or higher appears to be effective in clearing a significant percentage of facial telangectasias with a single pass. The side effects were minimal. [source] Concurrent Use of a Handheld Forced Cold Air Device Minimizes Patient Discomfort during Fractional PhotothermolysisDERMATOLOGIC SURGERY, Issue 2005Galen H. Fisher MD Objective:. To assess the analgesic effect of a handheld forced cold air device during fractional photothermolysis. Methods. Twenty patients who were being treated with full-face fractional photothermolysis were asked to rate their pain level with and without the handheld air-cooling device. Pain was rated on a scale of 1 to 10, with 10 being the worst. Results. Nineteen of 20 patients noted decreased pain with the addition of handheld cooling. The mean level of pain without air-cooling was 6.95 6 2.0. The mean level of discomfort with air cooling was 4.0 6 1.8. The mean decrease in pain with the addition of air-cooling was 2.9 6 1.8. Conclusion:. The addition of a handheld forced cold air device to cool the skin before and after fractional photothermolysis treatment is an effective adjunctive analgesic modality. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||