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Phytoplankton species exhibit fundamental temperature niches that drive observed species distributions linked to realized temperature niches. A recent analysis of field observations of Prochlorococcus showed that for all ecotypes, the realized niche was, on average, colder and wider than the fundamental niche. Using a simple trait‐based metacommunity model that resolves fundamental temperature niches for a range of competing phytoplankton, we ask how dispersal and local temperature variability influence species distributions and diversity, and whether these processes help explain the observed discrepancies between fundamental and realized niches for Prochlorococcus. We find that, independently, both dispersal and temperature variability increase realized temperature niche widths and local diversity. The combined effects result in high diversity and realized temperature niches that are consistently wider than fundamental temperature niches. These results have broad implications for understanding the drivers of phytoplankton biogeography as well as for refining species distribution models used to project how climate change impacts phytoplankton distributions. [ABSTRACT FROM AUTHOR]

Species coexistence attracts wide interest in ecology. Modern coexistence theory (MCT) identifies coexistence mechanisms, one of which, storage effects, hinges on relationships between fluctuations in environmental and competitive pressures. However, such relationships are typically measured using covariance, which does not account for the possibility that environment and competition may be more related to each other when they are strong than when weak, or vice versa. Recent work showed that such 'asymmetric tail associations' (ATAs) are common between ecological variables, and are important for extinction risk, ecosystem stability, and other phenomena. We extend MCT, decomposing storage effects to show the influence of ATAs. Analysis of a simple model and an empirical example using diatoms illustrate that ATA influences can be comparable in magnitude to other mechanisms of coexistence and that ATAs can make the difference between species coexistence and competitive exclusion. ATA influences may be an important new mechanism of coexistence. [ABSTRACT FROM AUTHOR]

Telomeres, DNA structures located at the end of eukaryotic chromosomes, shorten with each cellular cycle. The shortening rate is affected by factors associated with stress, and, thus telomere length has been used as a biomarker of ageing, disease, and different life history trade-offs. Telomere research has received much attention in the last decades, however there is still a wide variety of factors that may affect telomere measurements and to date no study has thoroughly evaluated the possible long-term effect of a storage medium on telomere measurements. In this study we evaluated the long-term effects of ethanol on relative telomere length (RTL) measured by qPCR, using blood samples of magpies collected over twelve years and stored in absolute ethanol at room temperature. We firstly tested whether storage time had an effect on RTL and secondly we modelled the effect of time of storage (from 1 to 12 years) in differences in RTL from DNA extracted twice in consecutive years from the same blood sample. We also tested whether individual amplification efficiencies were influenced by storage time, and whether this could affect our results. Our study provides evidence of an effect of storage time on telomere length measurements. Importantly, this effect shows a pattern of decreasing loss of telomere sequence with storage time that stops after approximate 4 years of storage, which suggests that telomeres may degrade in blood samples stored in ethanol. Our method to quantify the effect of storage time could be used to evaluate other storage buffers and methods. Our results highlight the need to evaluate the long-term effects of storage on telomere measurements, particularly in long-term studies. [ABSTRACT FROM AUTHOR]

Aims: We explored how long-term agricultural practices affect arbuscular mycorrhizal (AM) fungal traits and community structure. Methods: We sampled soil and roots from a 26-year-old field experiment comprising 16 replicated treatments, in which we manipulated tillage intensity (moldboard vs. chisel plow), fertilization (organic vs. mineral) and crop rotation (continuous barley vs barley-forage rotations) in a factorial design (N = 64). We measured AM fungal community-aggregated traits, namely the abundance of vesicles, arbuscules, extraradical mycelium (ERM) and spores. We characterized root-borne and soil-borne AM communities using Illumina sequencing. Results: Crop rotation was the main factor controlling AM fungal traits, with more arbuscules and ERM found in forage rotation plots, and more vesicles and spores found in continuous barley plots. Members of the Glomeraceae family were preferentially associated with continuous barley whereas the Gigasporaceae and Diversisporaceae families were overrepresented in the first stage of crop rotation. Trait-based and phylogenic filtering of AM fungal communities allowed us to speculate on different life history strategies among taxonomic families. AM community structure in soil responded to fertilizer type, whereas root-borne communities responded to crop rotation. We found the first evidence of temporal niche partitioning as a potential driver of coexistence among AM fungal taxa, resulting in higher species richness (i.e. storage effects). Conclusions: Crop rotation scheme strongly influences functional traits and coexistence of AM fungi, more so than soil disturbance intensity or fertilization regime. Future work is required to understand the implications of these shifts in AM fungal community structure for crop productivity. [ABSTRACT FROM AUTHOR]

Wholegrain brown rice (WBR) with significantly enhanced quality attributes has been recently achieved after ultra-high pressure (UHP) processing, but the process-induced changes in physicochemical parameters following subsequent storage for UHP-treated WBR are scarcely documented. So this work was designed to investigate the effects of UHP treatments (0.1–450 MPa/10 min) on chemical composition, microstructure, and the changes in chemical reactions during storage (20 days/30 °C) as indicated by volatile profiling, color development, and antioxidant activities for WBR grains, compared to high-intensity ultrasound (HIU) and germination (GER) pretreatments. Results showed that significant variation in physicochemical properties was caused by both processing approaches and storage duration. Color changes ( a *, b *, L *, and Δ E ) were slightly noticeable after storage for all WBR samples, and UHP-treated grains represented clearly visible browning reactions. In addition, hierarchically clustered heatmap suggested that volatile fingerprinting could be preliminarily separated according to different pretreatments and storage duration. After immediate treatments, total antioxidant activities presented a decrease by 14–28% for all treated grains compared to the unprocessed samples. Within storage process, GER and HIU samples showed steadily declining trends for antioxidant activities whereas a fluctuation was observed in UHP-treated grains. Besides, samples treated by 350/450 MPa maintained more antioxidants (91–102%) than the control (83–87%), GER (64–76%) and HIU (76–88%) samples at the end of storage. Multivariate analysis revealed a close relationship between color changes and antioxidant activity. These results indicated the necessity of a complete evaluation for possible processing effects on physicochemical and nutritional characteristics of WBR grains within the entire process extending immediate treatments to its prolonged storage and consumption, in order to achieve better quality control using the optimized processing parameters. Industrial relevance The selected emerging techniques including UHP, HIU and GER allow the acquisition of WBR products with improved texture and cooking properties as well as the enrichment of bioactive components. Nevertheless, the processed WBR grains must be subjected to a storage process before consumption. A more comprehensive understanding of the effects of newly-developed techniques on quality characteristics of WBR grains contributes to better control of products quality, particularly extending from immediate effects to the prolonged storage. [ABSTRACT FROM AUTHOR]

We investigated the stability of adrenocorticotropic hormone (ACTH) in plasma after freezing for different lengths of time. The plasma ACTH concentrations of 12 horses were measured on day 0 (baseline) and over time, after stimulation with thyrotropin-releasing hormone. Samples were stored at −80°C for 3, 7, 30, 60, and 90 d, or at −20°C for 3, 7, 30, and 60 d, or between ice packs at −20°C for 3 and 7 d prior to determination of ACTH concentration. ACTH concentrations were compared to baseline (non-frozen day 0 plasma) for each storage method using a mixed model with repeated measures in which each horse served as its own control and day was the repeated effect. Statistical significance was set at p ≤ 0.05, and 0.05 < p < 0.10 was considered a trend. Plasma ACTH frozen at −20°C or at −80°C resulted in degradation of ACTH compared to baseline samples at 60 and 90 d respectively. There was no degradation of ACTH after 7 d when stored between ice packs, or before 30 d at −20°C, or before 60 d at −80°C. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate the effects of evaporation, gamma irradiation and temperature on the total polyphenols, flavonoids and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activities of Tualang honey samples (n = 14) following storage over three, six or twelve months. The mean polyphenol concentrations of the six gamma irradiated honey samples at three, six and twelve months, respectively, were 96.13%, 98.01% and 102.03% higher than the corresponding values of the eight non-gamma irradiated samples. Similarly, the mean values for flavonoids at three, six and twelve months were 111.52%, 114.81% and 110.04% higher, respectively, for the gamma irradiated samples. The mean values for DPPH radical-scavenging activities at three, six and twelve months were also 67.09%, 65.26% and 44.65% higher, respectively, for the gamma irradiated samples. These data indicate that all gamma irradiated honey samples had higher antioxidant potential following gamma irradiation, while evaporation and temperature had minor effects on antioxidant potential.

Though olive oil is a perishable product, there is not a European regulation for maximum consumption time after production, in part because its durability depends on the storage conditions. The main objectives of this study were to compare the influence of the type of storage on changes of Portuguese virgin olive oils and to verify whether the addition of Catostylus tagi could increase the oxidative stability of olive oil. Over 12 months, the conservation status of monovarietal and blended olive oils in four contexts possible to be used by the consumer was monitored. The analyzed parameters were chlorophyll content, free acidity, peroxide value, specific extinction coefficients at 232 and 270 nm and delta K. Spaced determinations of iodine index and total tocopherol contents complemented the study. Results showed that at Mediterranean temperatures and normal storage procedure, the mean time to reach maximum peroxides value was 12-13 months. At artificial light storage, C. tagi was effective in reducing peroxides evolution by 11 %. [ABSTRACT FROM AUTHOR]

Analysis of fecal glucocorticoid (GC) metabolites has recently become the standard method to monitor adrenocortical activity in primates noninvasively. However, given variation in the production, metabolism, and excretion of GCs across species and even between sexes, there are no standard methods that are universally applicable. In particular, it is important to validate assays intended to measure GC production, test extraction and storage procedures, and consider the time course of GC metabolite excretion relative to the production and circulation of the native hormones. This study examines these four methodological aspects of fecal GC metabolite analysis in tufted capuchins ( Cebus apella). Specifically, we conducted an adrenocorticotrophic hormone (ACTH) challenge on one male and one female capuchin to test the validity of four GC enzyme immunoassays (EIAs) and document the time course characterizing GC metabolite excretion in this species. In addition, we compare a common field-friendly technique for extracting fecal GC metabolites to an established laboratory extraction methodology and test for effects of storing 'field extracts' for up to 1 yr. Results suggest that a corticosterone EIA is most sensitive to changes in GC production, provides reliable measures when extracted according to the field method, and measures GC metabolites which remain highly stable after even 12 mo of storage. Further, the time course of GC metabolite excretion is shorter than that described yet for any primate taxa. These results provide guidelines for studies of GCs in tufted capuchins, and underscore the importance of validating methods for fecal hormone analysis for each species of interest. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate the effects of evaporation, gamma irradiation and temperature on the total polyphenols, flavonoids and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activities of Tualang honey samples (n = 14) following storage over three, six or twelve months. The mean polyphenol concentrations of the six gamma irradiated honey samples at three, six and twelve months, respectively, were 96.13%, 98.01% and 102.03% higher than the corresponding values of the eight non-gamma irradiated samples. Similarly, the mean values for flavonoids at three, six and twelve months were 111.52%, 114.81% and 110.04% higher, respectively, for the gamma irradiated samples. The mean values for DPPH radical-scavenging activities at three, six and twelve months were also 67.09%, 65.26% and 44.65% higher, respectively, for the gamma irradiated samples. These data indicate that all gamma irradiated honey samples had higher antioxidant potential following gamma irradiation, while evaporation and temperature had minor effects on antioxidant potential. [ABSTRACT FROM AUTHOR]

The present investigation highlights the effect of storage on the physico-chemical status and bacteriological quality of sachet water produced in Port Harcourt, Nigeria for a period of four months. Ten brands of sachet water were collected within 24 hours of production and stored at ambient temperature. Sub-samples were drawn from the stock samples on monthly basis for physico-chemical measurement and on weekly basis for enumeration of total aerobic heterotrophic bacteria and indicator organisms using ASTM, APHA and WHO analytical methods. pH values increased in all brands to acceptable WHO limits within 8 weeks of storage and gradually decreased toward the end of the experiment. Dissolved oxygen, volatile organic matter and nitrate values decreased throughout the investigation period while phosphate and potassium values increased throughout the investigation period in all brands tested. Total aerobic heterotrophic bacterial count increased gradually in all brands to unacceptable limit within four weeks of storage and gradually diminished to zero level by the end of experiment. Total and faecal coliform appeared in 40% of sachet water samples analyzed within the first three weeks and were no longer detected throughout the investigation period. Escherichia coli was isolated in one brand at the onset while faecal Streptococci were absent throughout the investigation period. Results of the experiment indicate that 60% of the brands analyzed met the WHO guideline limit for drinking when stored at ambient temperature within four week period. However, storage beyond this period led to diminished aesthetic quality of sachet water and increased proliferation of bacteria to a level deleterious to human health. [ABSTRACT FROM AUTHOR]

Ecology Letters (2010) 13: 453–463 Environmental variability in space and time is a primary mechanism allowing species that share resources to coexist. Fluctuating conditions are a double edged sword for diversity, either promoting coexistence through temporal niche partitioning or excluding species by stochastic extinctions. The net effect of environmental variation on diversity is largely unknown. We examined the association between zooplankton species richness in lakes and environmental variability on interannual, seasonal and shorter time scales, as well as long-term average conditions. We analyzed data on physical, chemical and biological limnology in 53 temperate zone lakes in North America and Europe sampled over a combined 1042 years. Large fluctuations in pH, phosphorus and dissolved organic carbon concentration on different time scales were associated with reduced zooplankton species richness. More species were found in lakes that showed greater temperature variation on all time scales. Environmental variability on different time scales showed similar or, in some cases, stronger associations with zooplankton species richness compared with long-term average conditions. Our results suggest that temporal fluctuations in the chemical environment tend to exclude zooplankton species while temperature variability promotes greater richness. The results indicate that anthropogenic increases in temporal variability of future climates may have profound effects on biodiversity. [ABSTRACT FROM AUTHOR]

Chemical composition of the essential oil hydrodistilled from the Artemisia lobelii All., after a storage period of seven years, was studied by GC and GC/MS and compared with the chemical composition of the oil obtained right after drying the same plant material. Although two leading constituents of the compared oils were camphor and 1,8-cineole (36.6% and 17.9% in the oil distilled directly after plant material drying and 17.8% and 11.0% in the oil obtained after prolonged storage, respectively), significant decrease in the oil yield (from 0.17% to 0.09%) and increase in the number of components (from 26 to 120) during plant material storage was observed. These changes in the oil content and composition are most probably influenced by the evaporation of the volatile constituents from the plant material during storage, and by the chemical transformations of the plant native metabolites. [ABSTRACT FROM AUTHOR]

Copyright of Basic & Applied Ecology is the property of Urban & Fischer Verlag and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Wide variation in reproductive success is common among amphibians that breed in seasonal ponds, but persistence of adults can buffer against these fluctuations, particularly for long-lived species. We hypothesized that the frequent episodes of catastrophic failure of the marbled salamander ( ) enhance the importance of high terrestrial survival. At Rainbow Bay in South Carolina reproductive success was poor (<1 metamorph/breeding female) in nearly half of the 22 years that the species bred. Complete failure occurred in 6 of 22 years. To study catastrophic failure, we adapted an age-structured, individual-based model with density-dependent growth and survival of larvae. The model was based on extensive data from local field studies and experiments. With consistently good survival in the pond stages, the simulated population required survival probabilities in the upland stages (juveniles and adults) near 0.5/year to persist and near 0.8/year to achieve the increases observed. Catastrophic failure, occurring randomly with probability 0.5/year, created additional fluctuations in the population, raised the thresholds of survival required for persistence, and caused extinction under conditions that were otherwise favorable. The marbled salamander at Rainbow Bay is not at great risk of extinction because of catastrophic failure, but the risk increases dramatically if life span is decreased or frequency of failure is increased. Any reduction in terrestrial survival will have deleterious consequences by reducing the breeding populations at equilibrium, even if it does not jeopardize persistence. Our model provides assessments of risk that can be applied to poorly studied species with similar life histories, such as the endangered flatwoods salamander ( ). [ABSTRACT FROM AUTHOR]

Community level physiological profiles (CLPPs) have been implemented in many European soil monitoring programmes as a rapid tool for the assessment of the functional properties of soil microbial communities. However, this technique has not been harmonized among different laboratories. In this experiment, the changes of the CLPPs after storage of three Mediterranean forest soils were characterised for two sampling depths. The methods to store the samples were cooling, freezing and room temperature storage. Data presented in this study provide evidence that substantial changes can occur to the soil microbial community functions, regardless of the kind of storage. Changes in functional diversity and substrate evenness depended on the profile and sampling depth. The rate of consumption of the groups of substrates, however, shifted towards an enhanced utilisation of carboxylic acids, phenols and/or amines after 1 month storage at 4°C, regardless of the profile or sampling depth. This was attributed to the physical disruption of soil aggregates and exposure of relatively recalcitrant occluded organic matter. These effects levelled out during 1-year storage. The great sensitivity of CLPPs to storage treatment suggests to take care for immediate analysis after sampling. In case fresh samples are not available, freezing is recommended as a convenient alternative; in that case, however, the kinetic approach is required for data analysis. [Copyright &y& Elsevier]

Acoustic wave interaction with non-bonded contacts was found to be inherently non-linear due to asymmetrical stiffness distribution across the interface. A diode-type non-linearity results in local static elastic fields inside the contact, which are shown to be a source of transient longitudinal and shear DC-acoustic pulses polarized oppositely to a biasing contact stress. A parametric modulation of contact stiffness leads to acoustic instability effects, multiple sub-harmonics, and amplitude “self-modulation”, and provides chaotic noise-like non-linear acoustic excitations in solids. For realistic cracked flaws, contact acoustic non-linearity exhibits amplitude hysteresis and storage caused by acoustic wave impact on the defect. Maximum storage time observed comes to several hours for read-in time less than half a minute. A long-term non-linear memory is believed to be due to a slow relaxation of thermally induced micro-strain within the crack area. [Copyright &y& Elsevier]

For wastewater discharged into one branch of a narrow estuary, the resulting maximum concentration or temperature can vary markedly depending upon the proximity of the discharge site to the branching and upon how the rate of discharge is adjusted. Explicit formulae are derived for the optimal discharge rate to minimize the maximum concentration or temperature experienced in the estuary, while disposing of a given total wasteload over a tidal period. Graphs are used to show the approximately factors of two reductions in that minimized maximum concentration or temperature when the second branch is large, the discharge close to the branching, the decay rate large or the mean river flow large. By optimizing with respect to one pollutant, there is a reasonably wide range of other pollutants for which the environmental impact is nearly minimized. [ABSTRACT FROM AUTHOR]

Copyright of American Potato Journal is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Biomass pellets provide a pivotal opportunity in promising energy transition scenarios as a renewable source of energy. A large share of the current utilization of pellets is facilitated by intensive global trade operations. Considering the long distance between the production site and the end-user locations, pellets may face fluctuating storage conditions, resulting in their physical and chemical degradation. We tested the effect of different storage conditions, from freezing temperatures (−19 °C) to high temperature (40 °C) and humidity conditions (85% relative humidity), on the physicochemical properties of untreated and torrefied biomass pellets. Moreover, the effect of sudden changes in the storage conditions on pellet properties was studied by moving the pellets from the freezing to the high temperature and relative humidity conditions and vice versa. The results show that, although storage at one controlled temperature and RH may degrade the pellets, a change in the temperature and relative humidity results in higher degradation in terms of higher moisture uptake and lower mechanical strength. [ABSTRACT FROM AUTHOR]

The plant volatile profile and the essential-oil chemical composition change during the storage of plant material. The objective of this study was to develop a mathematical model able to predict, explain, and quantify these changes. Mathematical equations, derived under the assumption that the essential oil contained within plant material could be treated as an ideal solution (Raoult's law), were applied for tracking of postharvest changes in the volatile profile of Artemisia absinthium L. (the essential oils were analyzed by GC-FID and GC/MS). Starting from a specific chemical composition of an essential-oil sample obtained from plant material after a short drying period (typically 5-10 d), and by using the equations derived from this model, one could easily predict evaporation-induced changes in the volatile profile of the plant material. Based on the composition of the essential-oil sample obtained after a given storage time t, it is possible to identify those components that were involved in chemical reactions, both as reactants and possible products. The established model even allowed the recognition of pairs of transformation, i.e., 'daughter' products and their 'parent' compounds. The obtained results highlight that the essential-oil composition is highly dependent on the storage period of any plant material and urges caution in different types of phytochemical studies, especially chemotaxonomic ones, or practical application., (Copyright © 2015 Verlag Helvetica Chimica Acta AG, Zürich.)