Thermo-hydraulic performance of zeolite-bentonite mixtures stabilized with Zostera marina biomass

BackgroundCurrent dogma suggests sympathetic tone is the dominant regulator of rodent heart function at standard laboratory ambient temperature (LTA). Recent studies have shown, however, the high surface area to body mass ratio of rodents forces them to use non‐shivering thermogenesis driven by sympathetic stimulation of brown fat to maintain proper thermoregulation at LTA, raising heart rate (HR). When mice are studied at their thermoneutral ambient temperature (NTA) there is a decrease in HR and a formidable vagal component to HR regulation is revealed. HR regulation can be described by heart rate variability (HRV), a group of parameters which quantify the variation of beat‐to‐beat intervals. Additionally, HRV becomes reduced in advanced age due to reduced parasympathetic input.ObjectiveTo unravel the impact of autonomic input on age‐associated changes in HR and HRV over a range of ambient temperatures.MethodsHR was measured in young (3 mo) and aged (30 mo) male C57/BL6 telemetry‐implanted mice via in‐vivo ECG after a 3‐day acclimation period at 20ºC. Another ECG was recorded after a 3‐day acclimation period at 30ºC. HRV was evaluated in both time and frequency domains extrapolated from ECG recordings. Data was analyzed using linear mixed effects models. The double interaction term (temperature and age) in the models was used to evaluate the effect of temperature on HR and HRV by age group while correcting biases stemming from repeated measurements and uneven group sizes.ResultsChanging the ambient temperature altered mean HR of both age groups and several HRV indices in the aged mice. Mean HR of young mice was 595 ± 23 beats per minute (bpm) at 20ºC and decreased to 367 ± 14 bpm at 30ºC (p < 0.0001). Mean HR of aged mice was 622 ± 9.0 bpm at 20ºC and decreased to 323 ± 23 bpm at 30ºC (p < 0.0001) (Figure 1). Coefficient of variance (CV), an indicator of overall time‐domain HRV, was significantly reduced in old mice (2.24 ± 0.3 %) than in young mice (6.96 ± 1.5 %). This difference disappeared at 30ºC because the CV of the aged mice significantly increased to 6.57 ± 0.9 % (p < 0.0001) (Figure 2). Detrended fluctuation analysis (DFA), a measure of correlation within a time series, was significantly lower in the old mice at 30 C (0.81 ± 0.06) than 20ºC (1.1 ± 0.04) (p < 0.008) (Figure 3). The changes in CV and DFA suggest a restoration in complexity in the old mice at 30ºC. Aged mice also showed a significant increase in the high frequency power spectral density compared at 30ºC (175.4 ± 33.2 Hz) compared to 20ºC (20.79 ± 1.72), indicating increased parasympathetic tone at NTA (p < 0.0001) (Figure 4).ConclusionRodents are studied in cold‐stressed conditions at LTA and increased sympathetic stimulation distorts the correct view of autonomic balance. An age‐associated decline in HRV observed at LTA was ameliorated when mice were studied at their NTA. Thus, a true elucidation of autonomic neurotransmitter modulation of cardiovascular function alterations in advanced age require mammals to be at their NTA.Support or Funding InformationFunded by the National Institute of Health/National Institute on Aging Intramural Research Program.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

A temperature-controlled sample stage with an operational range of ~60 °C above or below ambient laboratory temperature (~ −35 to 85 °C) was constructed for in situ X-ray diffraction of minerals and materials using a Bruker D8 Discover diffractometer with θ-θ geometry. The stage was primarily designed for characterizing mirabilite-bearing samples from a Mars analog High Arctic perennial cold spring at an in situ temperature. Operation of the stage was demonstrated through the analysis of a synthetic sample of the hydrated sodium sulfate, mirabilite (Na 2 SO 4 ·10H 2 O). Mirabilite was held at −25 °C for approximately two hours without significant dehydration and then incrementally warmed to ambient laboratory temperature at 5 °C intervals, during the acquisition of in situ diffraction data. At ambient laboratory temperature, the mirabilite dehydrated and only polycrystalline thenardite (Na 2 SO 4 ) remained. Preliminary analysis of the cold spring precipitates demonstrates that when mirabilite is present in the sample the dehydration reaction is occurring between collection and analysis at ambient laboratory temperature. This temperature-controlled stage was designed for versatility and ease of X-ray access, with applications that can extend to many geological and planetary settings, including Mars analog environments.

A study was undertaken to assess the long-term chemical stability of dilute standard pesticide solutions of 4 compound classes. The solutions were studied under 4 storage conditions: freezer at —15°C; refrigerator at 3°C; ambient temperature in the dark; and ambient temperature on the bench top exposed to fluorescent and natural light. Pesticide compounds including 27 organochlorines, 20 organophosphates, 10 triazines, and 13 carbamates were monitored for periods of 6 months to 2 years. Most of the compounds were stable (<10% decomposition) under all conditions for the full length of the study. Solutions of CDEC, butylate, and disulfoton, however, decomposed when stored under all storage conditions. Solutions of carbaryl, methiocarb, and carbofuran decomposed when stored at ambient laboratory temperature with exposure to light. Recommendations are made for formulating solvents, storage, and practical shelf life of high concentration stock solutions and dilute gas chromatographic working standards representing 4 pesticide classes

Temperature and low concentration effects of the urease inhibitor N-(n-butyl) thiophosphoric triamide (nBTPT) on ammonia volatilization from urea

Effects of Elevated Thermal Regimes on Survival of Rainbow Trout ( Salmo Gairdneri) Alevins

Seagrasses are highly sensitive to human-induced disturbances and global environmental changes. Since the 1980s, Zostera marina meadows along the West Swedish coast (Skagerrak) have declined significantly, as evidenced by changes in morpho-anatomical traits, reductions in area coverage, and shifts in associated communities. However, infaunal assemblages within Z. marina meadows remain understudied compared to epifaunal communities and have not been previously used as indicators of seagrass regression. To investigate spatial variability in infaunal composition, we analysed samples from 15 coastal stations at depths of 1.5–3 m depth. Using an n-dimensional hypervolume framework, we assessed functional differences between infaunal and epifaunal communities. We examined infaunal community descriptors—such as species richness and individual abundance—biotic indices, environmental drivers (including wave exposure and Z. marina biomass), and correlations with epifauna. Variability in infaunal composition across sampling stations was primarily driven by differences in the abundance of dominant taxa, including the polychaete Capitella capitata, oligochaetes, nematodes, and chironomids. Several coastal stations, such as Marstrand and Finsbo, were classified as moderately polluted, though biotic indices, i.e., AMBI, M-AMBI and ISI, showed discrepancies. Spatial patterns in infaunal assemblages were mainly influenced by Z. marina biomass and maximum fetch, with a good representation of oligochaetes and chironomids in exposed stations. These findings suggest that infauna respond differently from epifauna but provide valuable additional insights into the ecological status, functional traits, and trophic diversity of Z. marina meadows. Integrating multiple community components is essential for a more comprehensive understanding of the processes and patterns driving seagrass ecosystem regression.

Experimental investigations of the reaction path in the MgO–CO2–H2O system in solutions with various ionic strengths, and their applications to nuclear waste isolation

Site investigations require the collection and analysis of representative environmental samples to delineate impacts, risks, and remediation options. When environmental samples are collected, concentrations of semi-volatile polycyclic aromatic hydrocarbons (PAHs) begin to change due to several processes, such as evaporation, adsorption, precipitation, photo, and microbial degradation. Preservation techniques are used to minimize these changes between collection and analysis. The most common techniques are refrigeration, freezing, and acidification. In the mid 1970s, regulatory agencies developed a holding time limit of 14days for PAHs in soil/sediment samples stored at < 6°C. The technical basis for this limit is not well defined yet failing to meet this limit may force resampling. This study examined the effectiveness of preservatives at maintaining PAH concentrations in sediment samples to 60days. Sediment samples were collected at three sites that were impacted with petrogenic and pyrogenic PAHs. Chemically preserved (sodium azide, NaN3) and unpreserved samples were analyzed at defined time intervals from 0 to 60days. Statistical analysis indicated acceptable preservation of PAHs in the sediment samples preserved with sodium azide for 60days when maintained at either ambient laboratory temperature or 4 ± 2°C, and for up to 21days with no preservative when maintained at 4 ± 2°C.

An annular centrifugal contactor pilot plant incorporating 30 stages of commercial 5 cm CINC V-02 units has been built and operated at INL during the past year. The pilot plant includes an automated process control and data acquisitioning system. The primary purpose of the pilot plant is to evaluate the performance of a large number of inter-connected centrifugal contactors and obtain temperature profile measurements within a 30-stage cascade. Additional solvent extraction flowsheet testing using stable surrogates is also being considered. Preliminary hydraulic testing was conducted with all 30 contactors interconnected for continuous counter-current flow. Hydraulic performance and system operational tests were conducted successfully but with higher single-stage rotor speeds found necessary to maintain steady interstage flow at flowrates of 1 L/min and higher. Initial temperature profile measurements were also completed in this configuration studying the performance during single aqueous and two-phase counter-current flow at ambient and elevated inlet solution temperatures. Temperature profile testing of two discreet sections of the cascade required additional feed and discharge connections. Lamp oil, a commercially available alkane mixture of C14 to C18 chains, and tap water adjusted to pH 2 were the solution feeds for all the testing described in this report. Numerous temperature profiles were completed using a newly constructed 30-stage centrifugal contactor pilot plant. The automated process control and data acquisition system worked very well throughout testing. Temperature data profiles for an array of total flowrates (FT) and contactor rpm values for both single-phase and two-phase systems have been collected with selected profiles and comparisons reported. Total flowrates (FT) ranged from 0.5-1.4 L/min with rotor speeds from 3500-4000 rpm. Solution inlet temperatures ranging from ambient up to 50° C were tested. Ambient temperature testing shows that a small amount of heat is added to the processed solution by the mechanical energy of the contactors. The temperature profiles match the ambient temperature of the laboratory but are nearly 10° C higher toward the middle of the cascade. Heated input solution testing provides temperature profiles with smaller temperature gradients and are more influenced by the temperature of the inlet solutions than the ambient laboratory temperature. The temperature effects of solution mixing, even at 4000 rpm, were insignificant in any of the studies conducted on lamp oil and water.

In fishes of the genus Xiphophorus, hybrid offspring of the spotted dorsal female platyfish, X. maculatus, and male swordtails, X. helleri, are genetically programmed to develop melanoma when raised at ambient laboratory temperatures. When these hybrid offspring were raised under hyperthermic conditions, there was no development of melanoma. Electron microscopy revealed degenerative changes in the melanocytes of heat-treated hybrids not seen in hybrids raised at ambient temperatures. The platyfish-swordtail melanoma system represents an appropriate model for the investigation of the relationship between hyperthermia and melanoma formation and treatment in poikilothermic vertebrates.

_ This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 210414, “First Evidence for Shale Production Decline as a Result of Formation Damage Caused by C60+ Paraffin Wax Deposition: A Permian Case Study,” by Amir Mahmoudkhani, SPE, Locus Fermentation Solutions, and Jonathan Rogers and Martin Shumway, SPE, Locus Bio-Energy Solutions, et al. The paper has not been peer reviewed. _ Analysis of production decline curves revealed that three candidate wells in West Texas depleted faster than indicated by a type decline curve, indicating a potentially abnormal permeability-reduction mechanism. A biosurfactant-based squeeze program was recommended and applied in three horizontal wells. The biosurfactant treatment offers an alternative and economical method for remediation of formation damage caused by high‑molecular‑weight paraffin wax deposition in porous media that does not require costly intervention techniques to apply. Introduction The Bone Springs horizontal oil play in the Delaware Basin spans from southeast New Mexico into West Texas. Stacked, multipay reservoirs, each with diverse rock properties, possess upside but also complexity. The initial targets in the play were conventional sandstones. Wells then tapped into carbonate lenses and, ultimately, low-permeability sandstones. As a result of horizontal drilling technology combined with hydraulic fracturing, very thin sands and other facies are now being produced. Generally, reservoir quality of this unconventional hydrocarbon system is controlled by carbonate content, where increased carbonate content typically is associated with lower productivity. Experimental Methods All crude oils exhibited precipitation of organics at ambient laboratory temperatures. Even after storing crudes at the bottomhole temperature of 140°F, a small amount of wax remained insoluble in bulk liquid. Samples of formation drill cuttings were received for various depth intervals between 8,500 and 12,000 ft. X‑ray diffraction analyses of solids revealed quartz as the major mineral phase, with clays and carbonates account for remaining phases. Combined fractions with 160-micron size were used for microcolumn oil-recovery screening tests. Carbon distributions of oils and waxes were performed by high-temperature gas chromatography (HTGC). The Du Noüy ring method was used to measure static surface tensions of biosurfactant solutions at different concentrations and was applied to calculate critical micelle concentrations at ambient temperature. Interfacial tension (IFT) measurements were performed using a drop-shaped tensiometer using the pendant-drop method. Finally, the IFTs of oil in synthetic formation water and in biosurfactant solutions prepared in city tap water were determined. Contact-angle measurements also were performed. The wax-appearance temperature (WAT) of crude and wax samples was determined by the differential scanning calorimetry method. Spontaneous imbibition experiments were performed using the Amott-cell method at reservoir temperature. Berea sandstone core plugs (25×50 mm) with a permeability of 385 md and porosity of 18.4% were used. Core plugs were saturated with homogenized crude oil samples at 140°F for 7 days.

The existing engineering properties of soils cannot always provide sufficient strength and optimization, resulting in the need for soil improvement. There are many methods and additive materials currently used in soil improvement. However, if the method to be used includes an alternative additive material, the material's sustainability, environmental friendliness and low cost play a major role considering the increasing world population and energy need. At the same time, the increasing population's demand for energy and the resulting increase in the number of energy structures increase the interaction of the soils with temperature. When all these are evaluated together, seaweed-added mixtures, terminologically known as "Zostera marina", were created within the scope of this study and their hydraulic conductivity behavior was examined under room and high temperatures. Dried seaweed is a sustainable, low-cost marine plant that has been used for thermal insulation for years in countries with a cold climate, such as Denmark. In this study, seaweed additive was added to zeolite-bentonite mixtures and hydraulic conductivity tests of the mixtures were determined under room and high temperatures (40°C). Thus, the effects of additive and temperature effects on permeability were examined separately. The test results showed that the seaweed additive had a reducing effect on hydraulic conductivity behavior at room temperature, while permeability increased under high temperature, parallel to the literature.

Elevated environmental temperature and methamphetamine neurotoxicity

Stability of hydrolytic enzyme activity and microbial phosphorus during storage of tropical rain forest soils

Abstract. We studied the population dynamics and reproductive traits of two phytal gastropods, Lirularia iridescens and Hiloa tristis, inhabiting a seagrass bed consisting of two seagrass species, Zostera marina and Zostera caulescens, in Otsuchi Bay, north‐eastern Japan. The main objectives of the study were to (1) determine seasonal and between‐substrata variations in gastropod populations and (2) examine two major factors potentially responsible for the variations, namely space (seagrass) and food (epiphytes). The biomass of Z. marina reached a peak in summer and decreased through autumn, whereas the biomass of Z. caulescens showed little seasonal fluctuation. Epiphyte biomass was maximum in April and remained low from summer to winter on both seagrass substrata. The population densities of both gastropod species increased rapidly due to increases in their new recruits from May to July for L. iridescens, from June to October for H. tristis. Eggs of L. iridescens were found in almost all months of the study period, with a breeding peak in April, whereas oviposition of H. tristis occurred only from June to October. The new recruits of both gastropods grew rapidly, with their abundance decreasing from summer to autumn. The peak densities of new recruits of the two species coincide with that of seagrass biomass rather than epiphyte biomass, and the juveniles grew when the epiphyte biomass was fairly low. Hence, large postrecruitment declines in gastropods may be caused by food shortage. Egg density, size structure and growth rate of both gastropod species were not significantly different between seagrass substrata. Total abundance was not significantly different for L. iridescens. For H. tristis, however, abundance was lower on Z. caulescens than Z. marina during most of the year, mainly due to higher post‐recruitment decline on the former. The ability of L. iridescens to breed continuously may enable them to successfully inhabit two seagrass species with different phenology, whereas the much shorter breeding season of H. tristis, which coincides with the periods of higher Z. marina biomass, may be more adaptive for inhabiting Z. marina than Z. caulescens.