Recommended Temperature Range Research Articles

Stability of Tranexamic Acid after 12-Week Storage at Temperatures from –20°C to 50°C

Background. Tranexamic acid (TXA) is an antifibrinolytic agent that reduces blood loss during surgery, decreases mortality in civilian and military trauma populations, was adopted for prehospital use by the British military, and is now issued to U.S. Special Operations Forces for use on the battlefield. Objective. This study tested whether storage of TXA ampoules at four temperatures (–20°C, 4°C, 22°C, or 50°C) for 1, 2, 4, and 12 weeks would result in chemical degradation and the loss of activity to block streptokinase-induced fibrinolysis in human plasma. Methods. For each temperature and storage duration, normal plasma, plasma plus streptokinase (SK) (50 units/mL), and plasma + SK + TXA (0.2 μg/mL, n = 4) were tested for D-dimer (DD), for fibrin degradation products (FDP), by thromboelastography (to measure the units/mL of SK needed to get 100% fibrinolysis at 60 minutes [LY60]), and by high-performance liquid chromatography (HPLC). The results were similar for all temperatures and storage durations, and were therefore combined. Results. Streptokinase led to a rise in LY60, DD, and FDP that was significantly (p < 0.05) attenuated with TXA. The results in the three test conditions were LY60: 0.00% ± 0.00%, 70.52% ± 4.7%, 0.02% ± 0.01%; DD: 0.23 ± 0.1, 205.05 ± 101.59, 0.31 ± 0.01 mg/L; and FDP: <10, >40, and <10 μg/mL, respectively. The HPLC results showed no chemical breakdown of TXA. All TXA glass ampoules at –20°C were cracked by week 1. Conclusions. Except for the finding that TXA ampoules cracked when frozen, this study indicated that the drug remains effective when stored under conditions likely to be encountered in the prehospital environment and outside the manufacturer's recommended temperature range for at least 12 weeks.

A Study of the Spawning Ecology and Early Life History Survival of Bonneville Cutthroat Trout

AbstractWe completed a large‐scale field experiment in four tributaries of the Logan River, Utah, where the largest metapopulation of imperiled Bonneville cutthroat troutOncorhynchus clarkii utahpersists. We documented the spatial and temporal distributions of spawners, quantified substrate use versus substrate availability, and evaluated differences in hatch and emergence fry success between and among sites in relation to habitat characteristics. We observed considerable variability in the timing, magnitude, and duration of spawning among study areas (streams), in part as a function of a variable, multipeaked hydrograph. Nevertheless, across study areas, &gt;70% of redds were constructed on the final descending limb of the hydrograph. Despite large differences in the amount of spawning substrate available, Bonneville cutthroat trout utilized a narrow range of substrate and sizes (3–80 mm) similar to that utilized by other subspecies of cutthroat trout, albeit biased towards larger sizes. Water temperatures generally remained below the recommended range (6–17°C) for spawning; however, the viability of this metapopulation of cutthroat trout suggests that the recommended temperature range for spawning is overestimated for this subspecies and (or) does not account for local thermal adaptation. Hatch varied from 43% to 77% and emergence survival from 39% to 65% among streams, and within‐stream variability was substantial; both survival rates declined significantly as a function of increased fine sediment concentrations. Egg development rates were nearly 50% greater in a high‐elevation tributary where redd counts were also lowest. In high, mountain systems with short growing seasons, this incubation delay likely presents a significant growth disadvantage for age‐0 trout. Our research enhances our understanding of Bonneville cutthroat trout spawning ecology and early survival and provides critical information for aiding in the development of benchmarks for their recovery. Effective conservation efforts should be directed towards minimizing anthropogenic activities that result in excess sedimentation in their critical spawning tributaries.Received April 15, 2011; accepted February 7, 2012

Reproductive toxicity of bisphenol A and cadmium in Potamopyrgus antipodarum and modulation of bisphenol A effects by different test temperature

An OECD initiative for the development of mollusc-based toxicity tests for endocrine disrupters and other chemicals has recommended three test species with respective test designs for further standardisation. Preparing a subsequent pre-validation study we performed a reproduction test with Potamopyrgus antipodarum, determining the concentration range of the selected test substances, bisphenol A (BPA) and cadmium (Cd). At 16 °C, the recommended test temperature, the number of embryos in the brood pouch was increased by BPA and decreased by Cd (NOEC: 20 μg BPA/L and 1 μg Cd/L). Coinstantaneous BPA tests at 7 °C and 25 °C demonstrated a temperature dependency of the response, resulting in lower NOECs (5 μg/L respectively). As expected, reproduction in control groups significantly varied depending on temperature. Additional observations of the brood stock showed seasonal fluctuations in reproduction under constant laboratory conditions. The recommended temperature range and test conditions have to be further investigated.

A review of the performance of domestic refrigerators

This paper reviews the published data on the performance and use of domestic refrigerators throughout the world in the last 30 years. While there is considerable legislation defining maximum temperatures during the production, distribution and retailing of chilled food, as soon as the consumer purchases the food, it is outside of any of these legislative requirements. Inadequate domestic refrigeration or cooling is frequently cited as a possible factor in food poisoning incidents. It is clear from the many published surveys that many refrigerators throughout the world are running at higher than recommended temperatures. Since even these recommended temperatures are higher than the 0 to 1 °C that is usually the recommended temperature range for storing fish and seafood, meat and many chilled products the current situation is even more detrimental to maintaining the high quality life of chilled foods. Despite numerous surveys around the world, how refrigerator temperatures and cleanliness impacts on consumer health remains to be fully assessed.

Shell Temperatures for a Single-Heater Diffuser

A new diffuser/permeator design has been proposed for a new Savannah River Site tritium project. The use of a single heaterwell in the center of the shell had raised concerns that the Pd/Ag coils may be shielding radiative heat transfer to the walls thus reducing Pd/Ag tube temperatures near the shell below the recommended minimum operating temperature.The diffuser was fitted with thermocouples to measure shell temperatures during testing. Tests were run with the shell evacuated, helium Feed flows of 0, 1000, and 2000 sccm; Bleed pressures ranging from 0 to 203 kPa, and heater temperatures of 650, 675, and 700°C. Hydrogen permeation tests were run with two hydrogen/helium mixtures and Feed rates to simulate 1st and 2nd stage diffuser operations.Approximately 20 hours were required to bring the diffuser from ambient temperature to steady-state conditions. For tests with a heater temperature of 675°C and no hydrogen flow, helium flow rate and pressure had little impact on the measured shell temperatures, the thermowell temperature, roughly 415°C, and altered heater output by only 11 watts. Conversely, controlling the thermowell temperature to 415°C during hydrogen permeation tests increased heater power output, lowered heater temperature, and increased shell temperatures. The tests showed the diffuser can perform its intended function with reasonable assurance that the Pd/Ag tubes were within the recommended temperature range.

Effects of 1-methylcyclopropene on ripening of greenhouse tomatoes at three storage temperatures

Abstract Tomatoes (Lycopersicon esculentum Mill., cv. Rapsodie) were harvested at the mature green stage and treated with 250 nl l−1 1-methylcyclopropene (1-MCP) for 24 h at 20 °C. The fruit were then stored for 24 days at 15, 20 or 25 °C at 90–95% relative humidity. Sampling was carried out at 0, 6, 12, 18 and 24 days after treatment. Treatment with 1-MCP delayed ripening as measured by changes in lycopene, chlorophyll, hue angle, polygalacturonase (PG) activity and tissue firmness. Ripening was delayed by 6 days at 25 °C, by 12 days at 20 °C, and by 18 days at 15 °C in 1-MCP-treated fruit. In general, 1-MCP only delayed the onset of ripening-related changes and did not significantly alter final values for measures of firmness, color (hue angle), PG activity, and lycopene and chlorophyll contents at a particular storage temperature. The results suggest that 1-MCP is most effective at delaying ripening of mature-green tomatoes when they are stored near the currently recommended temperature range of 12.5–15 °C.

I MPROVEMENTS IN P REHOSPITAL M EDICATION S TORAGE P RACTICES IN R ESPONSE TO R ESEARCH

Previously the authors showed that prehospital medications were stored outside their recommended temperature range. In response, the state office of emergency medical services (EMS) issued regulations regarding temperature control and monitoring of prehospital medications. Objective: To determine the impact of previous research (on medication storage conditions) on current practices among the mobile intensive care units (MICUs) within the state. Methods: A statewide, structured telephone survey of MICU directors was conducted between April and December 2000. Questions focused on changes in storage and monitoring practices (including modifications to vehicles, medication boxes, and the use of temperature monitoring devices) since the authors' previous research. Results: Thirty-three of 35 (94%) programs (100 vehicles) participated in the survey. Eighty-five percent changed their practices since the research five years ago. Of the five that did not change, three already had temperature control measures in place, while two have not made any changes. Twenty-one (63%) of the programs reported changing specifically because of state regulations. Eighty-one percent of the programs have taken some measure to control temperature. Currently, 63% of the 100 vehicles in use have both heating and cooling devices specifically for the medications, whereas 14% have only a heater and 23% have neither. Thirty-one (94%) MICUs monitor the temperature in some manner: 42% in the vehicle, 58% in the medication box. Of these, 68% are using 30-day electronic temperature data recorders, whereas 32% are using nonrecording digital thermometers. Conclusions: This survey demonstrates a positive impact from previous research. Most of the MICUs in the state have changed their practices in controlling and monitoring prehospital medication storage temperature.

α Function for a Series of Hydrocarbons to Peng−Robinson and van der Waals Equations of State

This paper reports estimated coefficients for the α function based on vapor pressure data to a series of 438 components, mainly hydrocarbons, for both van der Waals and Peng−Robinson equations of state (EoS). The α function utilized for the attractive term is the one proposed by Mathias and Copeman in 1983, and it improves the cubic EoS calculations. Accurate vapor-pressure correlations and critical data required for the estimation of the constants were retrieved from two databases, i.e., AIChE DIPPR and the Reid et al. (The Properties of Gases and Liquids; McGraw-Hill: New York, 1987) reference book. The method of calculation is described, and the constants are tested with respect of their representation of thermodynamic properties, mainly in terms of the vapor-pressure deviations. The behavior of density and enthalpy EoS predictions is also evaluated. The estimated coefficients for the α function are reported in the Supporting Information and may be applied as a data bank in a simulator, providing more accurate thermodynamic property calculations in the recommended temperature range, as demonstrated.

Vaccine storage in pharmacies on the Central Coast of New South Wales.

Pharmacies on the Central Coast of NSW were surveyed to assess the ability of refrigerators used for vaccine storage to maintain the recommended temperature range (2 to 8 degrees C). Refrigerators used for vaccine storage were monitored over a 3-day period using a temperature data logger. Fifty-nine (59) retail pharmacies were identified. The response rate was 90% (53/59) and 52 refrigerators were monitored successfully. Only 10 (19%) of the refrigerators maintained temperatures wholly within the recommended range for the 3-day monitoring period. The remaining refrigerators were considered in three groups--refrigerators keeping temperatures in the range 0.1 to 11.9 degrees C, below 0 degree C and above 8 degrees C for most of the time. There were 15 (29%), 12 (23%) and 15 (29%) refrigerators in these groups respectively keeping temperatures in the recommended range for 91%, 19% and 30% of the time. Of the refrigerators achieving temperatures below 0 degree C, none went below -5 degrees C and on average they kept temperatures less than 0 degree C for 49% of the time. This survey highlights the need for vigilance in vaccine storage for immunisation programs to be successful. Of the vaccines affected by freezing, hepatitis B vaccine was identified as being most at risk.

Laboratory reference values for a group of captive Ball Pythons (Python regius)

Abstract Objective Laboratory reference values, including hematologic and serum biochemical variables, and oropharyngeal bacteria flora, were determined in a group of captive Ball Pythons (Python regius). Animals 20 adult Ball Pythons, weighing between 700 and 1,510 g, were allowed to acclimate at the recommended temperature range for the species (25 C nighttime, up to 30 C daytime), then were evaluated for internal parasites and treated with appropriate medication prior to the start of the study. Procedure Hematologic values determined included WBC, hemoglobin, hematocrit, plasma protein, and differential cell count. Clinical biochemical analysis included determination of glucose, uric acid, calcium, phosphorus, total protein, alanine transaminase, alkaline phosphatase, and aspartate transaminase values. In addition to blood values, oropharyngeal swab specimens of the mouth were submitted for culture to determine the species of bacteria found in this population. Descriptive statistics were calculated for each hematologic and clinical biochemical value. Mean, SEM, and ranges were calculated. Results Hematologic values were similar to those reported in other snake species, except the hematocrit, which was lower. Clinical biochemical values different from those of other species were alkaline phosphatase activity, which was lower, and calcium and phosphorus concentrations, which were lower than values in other species. Bacteria isolated from the oropharynx were principally gram-negative organisms. Conclusion Reference intervals reported in this study are important for establishing a database for comparative studies of Ball Pythons in other locations and under different husbandry conditions. Clinical Relevance Accumulated laboratory reference values will assist veterinarians in assessing the health status of Ball Pythons. (Am J Vet Res 1996;57:1304-1307)

Conversion electron Mössbauer spectroscopy and x-ray photoemission spectroscopy studies of thermal oxidation of Fe67Co18B14Si1 metallic glass

The oxidation kinetics and associated structural and chemical transformations in the Fe67Co18B14Si1 metallic glass have been investigated by using the techniques of conversion electron Mössbauer spectroscopy (CEMS) and x-ray photoemission spectroscopy (XPS). The as-quenched as well as vacuum-annealed samples of the metallic glass have been subjected to thermal treatment in air at 100, 300, and 390 °C for 1/2 h in each case. The information regarding the structural transformations and chemical reactions has been obtained by deconvoluting the complex CEMS spectra and analyzing the contributions of various elements to the XPS spectra. It is shown that oxygen incorporation in the glass initiates the process of recrystallization of the glassy state at a temperature which is lower as compared to its temperature of recrystallization in vacuum. The oxygen-coordinated phases in the oxide scale and the other phases precipitated due to the reactive thermal treatment have been identified and the physical mechanisms underlying the observed effects have been commented upon. Experiments have also been performed to examine the transformations occurring in the metallic glass upon its prolonged thermal treatment in air at a typical temperature (∼100 °C) within the recommended temperature range (25–125 °C) for its use in applications. It has been demonstrated that the surface layers of the as-received glass are affected by such a treatment, though the sample preannealed at 300 °C remains relatively unaffected. The observations made on the basis of CEMS and XPS studies have been supported by x-ray diffraction and resistance-annealing measurements.