Heat wave effects on biomass and vegetative growth of macrophytes after long-term adaptation to different temperatures: a mesocosm study

Abstract Research on the behavioral responses of animals to extreme weather events, such as heat wave, is lacking even though their frequency and intensity in nature are increasing. Here, we investigated the behavioral response to a simulated heat wave in two species of antlions (Neuroptera: Myrmeleontidae). These insects spend the majority of their lives as larvae and live in sandy areas suitable for a trap-building hunting strategy. We used larvae of Myrmeleon bore and Euroleon nostras, which are characterized by different microhabitat preferences—sunlit in the case of M. bore and shaded in the case of E. nostras. Larvae were exposed to fluctuating temperatures (40 °C for 10 h daily and 25 °C for the remaining time) or a constant temperature (25 °C) for an entire week. We found increased mortality of larvae under heat. We detected a reduction in the hunting activity of larvae under heat, which corresponded to changes in the body mass of individuals. Furthermore, we found long-term consequences of the simulated heat wave, as it prolonged the time larvae needed to molt. These effects were pronounced in the case of E. nostras but did not occur or were less pronounced in the case of M. bore, suggesting that microhabitat-specific selective pressures dictate how well antlions handle heat waves. We, thus, present results demonstrating the connection between behavior and the subsequent changes to fitness-relevant traits in the context of a simulated heat wave. These results illustrate how even closely related species may react differently to the same event.

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Comparative Labelling and Biokinetic Studies of 99mTc-EDTA(Sn) and 99mTc-DTPA(Sn)

Nuklearmedizin ◽

10.1055/s-0037-1620603 ◽

1977 ◽

Vol 16 (01) ◽

pp. 30-35 ◽

Cited By ~ 1

Author(s):

N. Agha ◽

R. B. R. Persson

Keyword(s):

Complex Formation ◽

Significant Influence ◽

Room Temperature ◽

Ph Value ◽

Maximum Activity ◽

Reduction Step ◽

Labelling Yield ◽

Different Temperatures ◽

Kinetics Of

SummaryGelchromatography column scanning has been used to study the fractions of 99mTc-pertechnetate, 99mTcchelate and reduced hydrolyzed 99mTc in preparations of 99mTc-EDTA(Sn) and 99mTc-DTPA(Sn). The labelling yield of 99mTc-EDTA(Sn) chelate was as high as 90—95% when 100 μmol EDTA · H4 and 0.5 (Amol SnCl2 was incubated with 10 ml 99mTceluate for 30—60 min at room temperature. The study of the influence of the pH-value on the fraction of 99mTc-EDTA shows that pH 2.8—2.9 gave the best labelling yield. In a comparative study of the labelling kinetics of 99mTc-EDTA(Sn) and 99mTc- DTPA(Sn) at different temperatures (7, 22 and 37°C), no significant influence on the reduction step was found. The rate constant for complex formation, however, increased more rapidly with increased temperature for 99mTc-DTPA(Sn). At room temperature only a few minutes was required to achieve a high labelling yield with 99mTc-DTPA(Sn) whereas about 60 min was required for 99mTc-EDTA(Sn). Comparative biokinetic studies in rabbits showed that the maximum activity in kidneys is achieved after 12 min with 99mTc-EDTA(Sn) but already after 6 min with 99mTc-DTPA(Sn). The long-term disappearance of 99mTc-DTPA(Sn) from the kidneys is about five times faster than that for 99mTc-EDTA(Sn).

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Impact of Prolonged Exposure of Eleven Years to Hot Seawater on the Degradation of a Thermoset Composite

Polymers ◽

10.3390/polym13132154 ◽

2021 ◽

Vol 13 (13) ◽

pp. 2154

Author(s):

Amir Hussain Idrisi ◽

Abdel-Hamid I. Mourad ◽

Muhammad M. Sherif

Keyword(s):

Exposure Time ◽

Prolonged Exposure ◽

Mechanical Performance ◽

Matrix Cracking ◽

Pull Out ◽

Strength Based ◽

Different Temperatures ◽

River Line ◽

Composite Samples

This paper presents a long-term experimental investigation of E-glass/epoxy composites’ durability exposed to seawater at different temperatures. The thermoset composite samples were exposed to 23 °C, 45 °C and 65 °C seawater for a prolonged exposure time of 11 years. The mechanical performance as a function of exposure time was evaluated and a strength-based technique was used to assess the durability of the composites. The experimental results revealed that the tensile strength of E-glass/epoxy composite was reduced by 8.2%, 29.7%, and 54.4% after immersion in seawater for 11 years at 23 °C, 45 °C, and 65 °C, respectively. The prolonged immersion in seawater resulted in the plasticization and swelling in the composite. This accelerated the rate of debonding between the fibers and matrix. The failure analysis was conducted to investigate the failure mode of the samples. SEM micrographs illustrated a correlation between the fiber/matrix debonding, potholing, fiber pull-out, river line marks and matrix cracking with deterioration in the tensile characteristics of the thermoset composite.

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Evaluation of long-term frozen storage of plasma for measurement of high-density lipoprotein and its subfractions by precipitation

Clinical Chemistry ◽

10.1093/clinchem/36.5.783 ◽

1990 ◽

Vol 36 (5) ◽

pp. 783-788 ◽

Cited By ~ 16

Author(s):

M N Nanjee ◽

N E Miller

Keyword(s):

High Density Lipoprotein ◽

Liquid Nitrogen ◽

Frozen Storage ◽

Density Lipoprotein ◽

High Density ◽

Long Term Stability ◽

Long Term Storage ◽

Different Temperatures ◽

Edta Plasma

Abstract The concentration of high-density lipoprotein cholesterol (HDL-C) in plasma is now established as an independent risk factor for coronary heart disease, but more data are needed on the relative risk-predictive powers of different HDL subclasses. For epidemiologic and clinical purposes, isolation of HDL from other lipoproteins and separation of its two major subclasses, HDL2 and HDL3, are performed most conveniently by precipitation. Although storage of plasma is commonly necessary, little information is available on the long-term stability of HDL subclasses at different temperatures. Therefore, we quantified HDL-C, HDL2-C, and HDL3-C by dual precipitation with heparin-MnCl2/15-kDa dextran sulfate (H-M/DS) in samples of EDTA-plasma from 93 healthy subjects, after storage for one to 433 days at -20 degrees C, at -70 degrees C, or in liquid nitrogen (-196 degrees C). Fourteen samples (15%) were stored for a year or longer. At -20 degrees C, HDL-C decreased by 4.8% per year and HDL3-C decreased by 6.9% per year (P = 0.002 for both variables) relative to results obtained with samples stored in liquid nitrogen; total cholesterol, HDL2-C, and triglyceride did not change significantly at this temperature. When stored at -70 degrees C, none of the lipids showed any change relative to results obtained with liquid nitrogen. Thus, long-term storage of EDTA-plasma at -20 degrees C is unsuitable for subsequent quantification of HDL-C and its subclasses by H-M/DS dual precipitation. Storage at -70 degrees C is preferable, and is as reliable as storage in liquid nitrogen.

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Seed longevity of maize conserved under germplasm bank conditions for up to 60 years

Annals of Botany ◽

10.1093/aob/mcab009 ◽

2021 ◽

Author(s):

Filippo Guzzon ◽

Maraeva Gianella ◽

Jose Alejandro Velazquez Juarez ◽

Cesar Sanchez Cano ◽

Denise E Costich

Keyword(s):

Seed Germination ◽

Plant Genetic Resources ◽

Seed Viability ◽

Storage Conditions ◽

Seed Longevity ◽

Germplasm Bank ◽

Significant Difference ◽

Different Temperatures ◽

Germination Experiments

Abstract Background and Aims The long-term conservation of seeds of plant genetic resources is of key importance for food security and preservation of agrobiodiversity. Nevertheless, there is scarce information available about seed longevity of many crops under germplasm bank conditions. Methods Through germination experiments as well as the analysis of historical monitoring data, we studied the decline in viability manifested by 1000 maize (Zea mays subsp. mays) seed accessions conserved for an average of 48 years at the CIMMYT germplasm bank, the largest maize seedbank in the world, under two cold storage conditions: an active (–3 °C; intended for seed distribution) and a base conservation chamber (–15 °C; for long-term conservation). Key Results Seed lots stored in the active chamber had a significantly lower and more variable seed germination, averaging 81.4 %, as compared with the seed lots conserved in the base chamber, averaging 92.1 %. The average seed viability detected in this study was higher in comparison with that found in other seed longevity studies on maize conserved under similar conditions. A significant difference was detected in seed germination and longevity estimates (e.g. p85 and p50) among accessions. Correlating seed longevity with seed traits and passport data, grain type showed the strongest correlation, with flint varieties being longer lived than floury and dent types. Conclusions The more rapid loss of seed viability detected in the active chamber suggests that the seed conservation approach, based on the storage of the same seed accessions in two chambers with different temperatures, might be counterproductive for overall long-term conservation and that base conditions should be applied in both. The significant differences detected in seed longevity among accessions underscores that different viability monitoring and regeneration intervals should be applied to groups of accessions showing different longevity profiles.

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Heat waves in Berlin and Potsdam, Germany – Long‐term trends and comparison of heat wave definitions from 1893 to 2017

International Journal of Climatology ◽

10.1002/joc.5962 ◽

2018 ◽

Vol 39 (4) ◽

pp. 2422-2437 ◽

Cited By ~ 14

Author(s):

Daniel Fenner ◽

Achim Holtmann ◽

Alexander Krug ◽

Dieter Scherer

Keyword(s):

Heat Wave ◽

Heat Waves ◽

Long Term Trends

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Using Forecast and Observed Weather Data to Assess Performance of Forecast Products in Identifying Heat Waves and Estimating Heat Wave Effects on Mortality

Environmental Health Perspectives ◽

10.1289/ehp.1306858 ◽

2014 ◽

Vol 122 (9) ◽

pp. 912-918 ◽

Cited By ~ 21

Author(s):

Kai Zhang ◽

Yeh-Hsin Chen ◽

Joel D. Schwartz ◽

Richard B. Rood ◽

Marie S. O’Neill

Keyword(s):

Heat Wave ◽

Heat Waves ◽

Weather Data ◽

Wave Effects

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Long-Term Impact of Moscow Heat Wave and Wildfires on Mortality

Epidemiology ◽

10.1097/ede.0000000000000251 ◽

2015 ◽

Vol 26 (2) ◽

pp. e21-e22 ◽

Cited By ~ 9

Author(s):

Dmitry Shaposhnikov ◽

Boris Revich ◽

Tom Bellander ◽

Getahun Bero Bedada ◽

Matteo Bottai ◽

...

Keyword(s):

Heat Wave ◽

Long Term Impact

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Evaluating sub-seasonal heatwave reforecasts of the ECMWF over Europe

10.5194/ems2021-146 ◽

2021 ◽

Author(s):

Natalia Korhonen ◽

Otto Hyvärinen ◽

Matti Kämäräinen ◽

Kirsti Jylhä

Keyword(s):

Heat Wave ◽

Heat Waves ◽

Lead Times ◽

Weather Forecasts ◽

Wave Forecast ◽

Extended Range ◽

Hot Days ◽

Medium Range ◽

Summer Temperatures

Severe heatwaves have harmful impacts on ecosystems and society. Early warning of heat waves help with decreasing their harmful impact. Previous research shows that the Extended Range Forecasts (ERF) of the European Centre for Medium-Range Weather Forecasts (ECMWF) have over Europe a somewhat higher reforecast skill for extreme hot summer temperatures than for long-term mean temperatures. Also it has been shown that the reforecast skill of the ERFs of the ECMWF was strongly increased by the most severe heat waves (the European heatwave 2003 and the Russian heatwave 2010).Our aim is to be able to estimate the skill of a heat wave forecast at the time the forecast is given. For that we investigated the spatial and temporal reforecast skill of the ERFs of the ECMWF to forecast hot days (here defined as a day on which the 5 days running mean surface temperature is above its summer 90th percentile) in the continental Europe in summers 2000-2019. We used the ECMWF 2-meter temperature reforecasts and verified them against the ERA5 reanalysis. The skill of the hot day reforecasts was estimated by the symmetric extremal dependence index (SEDI) which considers both hit rates and false alarm rates of the hot day forecasts. Further, we investigated the skill of the heatwave reforecasts based on at which time steps of the forecast the hot days were forecasted. We found that on the mesoscale (horizontal scale of ~500 km) the ERFs of the ECMWF were most skillful in predicting the life cycle of a heat wave (lasting up to 25 days) about a week before its start and during its course. That is, on the mesoscale those reforecasts, in which hot day(s) were forecasted to occur during the first 7&#8230;11 days, were more skillful on lead times up to 25 days than the rest of the heat wave forecasts. This finding is valuable information, e.g., in the energy and health sectors while preparing for a coming heat wave.The work presented here is part of the research project HEATCLIM (Heat and health in the changing climate) funded by the Academy of Finland.

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Single-Cell Tests to Explore the Reliability of Sofc Installations Operating Offshore

Energies ◽

10.3390/en13071624 ◽

2020 ◽

Vol 13 (7) ◽

pp. 1624

Author(s):

Nelson Thambiraj ◽

Ivar Waernhus ◽

Crina Suciu ◽

Arild Vik ◽

Alex C. Hoffmann

Keyword(s):

Cell Structure ◽

Oxygen Depletion ◽

X Ray Diffraction ◽

Short Term ◽

Sem Images ◽

Cathode Degradation ◽

Air Supply ◽

Different Temperatures ◽

Effect Of Oxygen

This paper studies the robustness of off-shore solid oxide fuel cell (SOFC) installations and the nature and causes of possible cell degradation in marine environments. Two important, cathode-related, impediments to ensuring SOFC reliability in off-shore installations are: cathode degradation due to salt contamination and oxygen depletion in the air supply. Short-term and long-term tests show the effect of salt contamination in the cathode feed on cell performance, and reveal the underlying cause of the degradation seen. SEM/X-ray Diffraction/(XRD) analyses made it possible to identify salt taken up in the cathode microstructure after the short-term testing while the macroscopic cell structure remained intact after the short-term tests. The long-term degradation was found to be more severe, and SEM images showed delamination at the cathode/electrolyte interface with salt present, something that was not seen after long-term testing without salt. The effect of oxygen depletion on the performance was also determined at three different temperatures using I-V curves.

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