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Experiments were conducted to characterize and develop predictive constitutive equations for the elastic-plastic, post-yield hysteresis behavior of Divinycell H100 foam at temperatures as low as −40°C. The initial elastic modulus and yield strength of the foam increased almost linearly by about 50% as temperatures decreased from 23 to−40°C. Post-yield hysteresis, which was described by strain hardening, viscoelasticity and damage also increased as the temperature fell to −40°C, but this behavior was curtailed by a sharp reduction in tensile and shear ductility as the foam approached its ductile-to-brittle transition temperature near −50°C. An anisotropic elastic-plastic, viscoelastic damage constitutive model was extended to predict cold temperature behavior. Good agreement was found between analytical predictions and the experimental results. The temperature-dependent constitutive equation can be used in conjunction with appropriate failure criteria to predict foam-core sandwich panel behavior in cold regions. [ABSTRACT FROM AUTHOR]

Thermal stress causes the reduction in productivity and harvest quality. To adapt to different temperature ranges, plants activate protecting metabolic pathways. Previous studies have reported that stressful environments due to abiotic stresses have an impact on the accumulation of glucosinolates (GSLs) in Brassicaceae plants. In order to determine the role of GSLs in the plant response to thermal stress, we conducted a study comparing four populations with a high and low GSL content. The GSL levels were analysed at different temperatures [control (20), 12 and 32 °C], detecting that populations with a higher GSL content increased their resistance to the cold. In addition, populations subjected to the cold increased the content of indolic GSLs. Populations with high levels of GSLs show higher levels of glucobrassicin (GBS) and sinigrin (SIN) under cold temperatures than plants grown under control conditions. High temperatures have a lower impact on GSLs accumulation. To elucidate the induced metabolic changes due to the accumulation of GSLs under cold conditions, we performed an untargeted metabolomic analysis and identified 25 compounds differentially expressed under cold conditions in the populations with a high GSL content. Almost 50% of these compounds are classified as lipids (fatty amides, monoradylglycerols, diterpenes, glycosylglycerols, linoleic acids and derivatives). Organoheterocyclic and nitrogenous organic compounds are also over-represented. Therefore, the current results suggest that GSLs play a key role in cold tolerance. Although the associated molecular mechanisms have not been elucidated, the non-targeted metabolomics assay shows a significant change in the lipid profile, with compounds that need to be studied further. [ABSTRACT FROM AUTHOR]

Cold stress restricts the growth and development of plants. Lignin plays an important role in stress resistance. However, there are few studies on lignin mechanisms regulation under low-temperature stress. In this study, the contents of both acid-soluble and -insoluble lignin were reduced after a short period of cold treatment. A targeted metabolomics analysis showed that the contents of caffeate, ferulic acid, coniferaldehyde, and p-coumaraldehyde decreased after cold stress, while the contents of L-phenylalanine and sinapaldehyde increased. The C3′H (p-coumaroylshikimate 3-hydroxylase) and COMT (caffeic acid O-methyltransferase) families, which catalyze the formation of caffeate and coniferaldehyde, were analyzed. Among them, the transcriptional levels of PtrC3′H1, PtrCOMTL4, and PtrCOMT1 were positively correlated with the decreased lignin after cold stimulation. The lignin-related transcription factor PtrMYBs, such as PtrMYB021, PtrMYB074, PtrMYB125/85, and PtrMYB103/46, were clearly induced by cold stress. The reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR) further verified that the level of transcription of key genes was consistent with the transcriptomic data. The identified key genes and metabolic intermediates in lignin synthesis provide a foundation for the functional characterization of the molecular mechanism of lignin biosynthesis under cold stress, which should help to efficiently utilize lignin in forest resources. [ABSTRACT FROM AUTHOR]

Based on the daily average temperature from March 19 to April 2, 2021 at three surface meteorological stations in western Guizhou and the daily average temperature, maximum temperature and minimum temperature from March 19 to April 2, 2021 at 12 main automatic meteorological stations of red cartridge kiwifruit base, the effects of low temperature and high temperature on flowering and pollination of red cartridge kiwifruit in early spring of 2021 were analyzed. The results showed that slight cold spell in later spring in western Guizhou occurred from March 21 to 23. The lower limit of the daily average temperature required for flowering period (12 °C or below) appeared in each base of red cartridge kiwifruit during March 21 -23, which affected the red cartridge kiwifruit trees in Faer, Houchang, Miluo, Shunchang, Panlong and Jichang bases flowering and pollinating before March 20. From March 29 to April 2, the daily maximum temperature of Faer and other eleven bases was 30 °C or above, which caused the wilting and abscission of flowers and young fruits of of red cartridge kiwifruit trees in Faer, Houchang, Miluo, Shunchang, Panlong, shaomi, Jichang and Aga bases blooming and pollinating before March 24, but the flowers of red cartridge kiwifruit trees in Langdai, Longhe, Pugu and Shuangfeng bases blooming and pollinating after March 28 were not damaged. [ABSTRACT FROM AUTHOR]

Aim: Animal studies are an important knowledge base when information from clinical trials is missing or conflicting. The goal of this systematic review and meta-analysis was to investigate the effect of conventional targeted temperature management (TTM) between 32-36 °C in animal cardiac arrest models, and to estimate the influence of effect modifiers on the pooled effect of TTM.Data Sources: We searched Medline and Scopus from inception to May 2020 for randomised controlled animal trials assessing the effect of conventional TTM versus normothermia on neurologic outcome after cardiac arrest. We extracted data on study characteristics, study quality data, neurologic outcome, mortality, and potential effect modifiers.Results: We retrieved 1635 studies, 45 studies comprising data of 981 animals met the inclusion criteria. Risk of bias was high in 17 studies and moderate in 28 studies. We undertook random-effects meta-analyses and meta-regression analyses to calculate the pooled effect and the influence of effect modifiers. There was a strong beneficial effect of TTM as compared to normothermia on neurologic outcome (standardised mean difference of 1.4 [95% CI -1.7 to -1.1; I2 = 75%]). Faster cooling rates, lower target temperature of TTM within the range of 32-36 °C, and shorter duration of cooling were independently associated with an increasing effect size of TTM.Conclusions: This systematic review of animal cardiac arrest studies showed a consistent favourable effect of postresuscitation TTM as compared to normothermia on neurologic outcome that increased with lower target temperatures. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the impact resistance and mechanical properties of a number of developed lightweight self-consolidating concrete (LWSCC) mixtures under cold temperatures. To achieve LWSCC mixtures with minimum possible density, the authors explored different replacement levels of normalweight fine or coarse aggregates by lightweight fine and coarse expanded slate aggregates. The studied parameters included testing temperature (+20°C, 0°C, and -20°C), type of lightweight aggregate (either fine or coarse expanded slate aggregates), binder content (550 and 600 kg/m3 [34.3 and 37.5 lb/ft3]), coarse-to-fine (C/F) aggregate ratio (0.7 and 1.0), and the use of polyvinyl alcohol (PVA) fibers (fibered and nonfibered mixtures). The results indicated that for all tested mixtures, decreasing the temperature of concrete below room temperature significantly improved the mechanical properties and impact resistance. Increasing the percentage of lightweight fine or coarse aggregate in the mixture showed more improvement in the mechanical properties and impact resistance under cold temperatures. However, the failure mode of all tested specimens appeared to be more brittle under subzero temperatures. It was also observed that the inclusion of PVA fibers helped to compensate for the brittleness that resulted from decreasing the temperature, and it further enhanced the impact resistance and mechanical properties under low temperatures. [ABSTRACT FROM AUTHOR]

An efficient management of the newborn dairy calf around birth results in reduced rearing costs and increased future milk yield. To maintain young calves healthy and maximize performance and profit it is important to create an environment that maintain low levels of stress. Low environment temperature directly affects newborn and young calves' performance, health and survival due hypothermia. For that reason, the adaptation of the dairy calf to the cold environment is important, with body responses of primary importance. However, some strategies may also be adopted to reduce cold stress induced by heat loss. There are several ways to aid the young calf in low environmental temperature, starting immediately after birth with colostrum feeding. Besides that, factors such as adequate housing, management and nutrition, result in significantly decrease morbidity and mortality, and similar growth rates as calves in the zone of thermoneutrality. The calf physiology adaptation to cope with cold stress and the positive effect of feeding systems, resulting in greater heat production, health, and performance will be approach in this literature review. [ABSTRACT FROM AUTHOR]

We have isolated several poly 3-hydroxybutyrate-co-3-hydroxyhexanoate (PHBH) degradable bacteria from the deep-sea sediment samples. The isolated microbes were involved into α-, γ- Proteobacteria group and the phylum Firmicutes, which were commonly diverged in the ocean environment. Four bacterial strains, Bacillus sp. MH10, Alteromonas sp. MH53, Psychrobacillus sp. PL87 and Rheinheimera sp. PL100, were selected as more active strains for the PHBH bio-degradation at high pressure and cold temperature conditions, and showed that those strains were piezotolerant up to 20–30 MPa. Our findings indicated that the PHBH could be well degraded not only in the ocean environment, but also at the deep-sea bottom, by means of those marine microorganisms. [ABSTRACT FROM AUTHOR]

Cold temperature is an important environmental factor that affects the lives of many organisms in various ways. In this study, cold temperature was found to promote the release of zoospores from Phytophthora sojae sporangia. To better understand this phenomenon, Illumina sequencing was used to examine the differential expression of P. sojae genes between three control libraries and three cold temperature (4°C) treatment libraries. The six libraries generated 1.04, 1.17, 1.11, 0.96, 1.23, and 1.13 million clean sequencing reads. Comparison of the gene expression levels between the control and cold treatment conditions revealed 175 differentially expressed genes (DEGs), including 38 up-regulated and 137 down-regulated genes in the cold temperature group compared to the control group. The DEGs were functionally classified using the Clusters of Orthologous Groups (COG) database, and the results indicated that these DEGs were mainly involved in signal transduction, translation, ribosomal structure and biogenesis, transcription and carbohydrate transport and metabolism. KEGG pathway analysis showed that the top 20 pathways significantly enriched in DEGs included amino sugar and nucleotide sugar metabolism, arginine and proline metabolism, and starch and sucrose metabolism. Some of the DEGs are involved in the release of zoospores from P. sojae sporangia is discussed in the present work. This information will be helpful for understanding the mechanism of zoospore release induced by cold temperature. [ABSTRACT FROM AUTHOR]

To investigate the effect of temperature on the recovery of aerobic granule stability, two continuous-flow reactors inoculated with disintegrated partial nitritation granules were operated at different temperatures for organic-free wastewater treatment. Granules disintegration and partial nitritation deterioration further occurred in the reactor (R1) operating at 25–28 °C. However, successful sludge re-granulation with a decrease of sludge volume index (SVI5) from 73 mL/g to 35 mL/g was observed in the reactor (R2) operated with the decreasing temperature from 20 °C to 12 °C. The reduced temperatures decreased the activity and growth rate of nitrifiers (from 47.2 mg/g VSS/h to 21.3 mg/g VSS/h), and selected the extracellular polymeric substance (EPS) producing bacteria (e.g., Flavobacterium and Rhodobacteraceae sp.). Correspondingly, an enhanced secretion of tightly-bound EPS (200.3–224.6 mg/g VSS in R2 vs 166.8–152.5 mg/g VSS in R1), particularly proteins, and an increased expression of quorum sensing-related enzyme genes (2.98% in R2 vs 2.75% in R1) were obtained. All of this contributed to the cold temperature-driven sludge re-granulation. The recovery of granular structure promoted the stable maintenance of efficient partial nitritation at low temperatures. Overall, this study gives insights into the positive role of cold temperatures on the stability of partial nitritation granules. [Display omitted] • Temperature effects on nitrifying granules were studied in continuous-flow reactors. • Granule disintegrated at 25–28 °C, but regranulation occurred at low temperatures. • Cold temperature enriched extracellular polymeric substance-producing microbes. • The mechanism of cold temperature-driven sludge regranulation was proposed. [ABSTRACT FROM AUTHOR]

A newly combined bioelectrochemical and sulfur autotrophic denitrification system was developed and steadily operated to treat nitrate polluted water at 10˚C for 270 d. The parameters hydraulic retention time (HRT) and current were continuously adjusted to achieve better nitrate removal efficiency. Results demonstrated that the sulfur autotrophic denitrification part (S-part) efficiency was effectively improved by adjusting the parameter HRT, while current was the key control parameter for the electrochemical part (E-part) at low temperatures in this CBSAD reactor. This CBSAD system had the ability to maintain pH balance, and the effluent SO2-4 concentration could be effectively controlled at cold temperatures in this combined autotrophic system. [ABSTRACT FROM AUTHOR]

Temperature is the most influential environmental parameter during egg incubation affecting embryo development, hatchability and post-hatch performance of broilers. Industrial incubation operates to control the temperature and humidity around the eggs closely based on predefined setpoints and keep fluctuations to a minimum. On the other hand, during brooding, the mother hen regularly leaves the nest for self-maintenance resulting in a striking difference between the constant industrial versus fluctuating natural incubation temperature profiles. Previous studies on ducks and laying hens have found fear and/or social behaviours to be affected by temperatures below recommended values during incubation, a similar result could be existing in commercial broilers. Therefore, this study examines the effect of lowering machine temperatures during incubation on behaviour. Three incubation treatments were defined with a constant machine temperature of 37.6 °C on embryonic day (ED) 0–13 and 19–21 with the machine temperature differing on ED 13–18: (1) Control (C ; 37.6 °C), (2) non-optimal Incubation Treatment (IT ; 36.6 °C), (3) Natural Treatment (NT , 30 °C for 30 min per day). Post-hatch fear and social behaviour were quantified using six scientifically accepted behavioural tests: three fear tests (novel object on day (d) 1 and d8, tonic immobility (d40), inversion (d42)), two social tests (isolation (d19) and social reinstatement (25)) and one social/fear test (emergence (d18 and d20)). For the emergence test, wherein the time taken for an individual chick to emerge from a T-shaped box was measured, a treatment effect was found on the latency to emerge (P < 0.05) with C chicks emerging more often and faster than IT chicks. As no differences for IT were found in other social tests, the emergence suggest IT chicks to be more hesitant towards novel environments. No differences were present between NT and C or NT and IT. For the isolation test, where an individual chick is visually and audibly isolated for 3 min and the number of vocalisations was measured, an interaction was found between treatment and sex (P < 0.001). Females vocalised more than males in IT and C, but this was not the case for NT. NT male chicks could thus be considered more sensitive to social separation, which could be explained by the higher impact of early stress, caused by the severe temperature drops in NT, having a stronger impact on the anxiety behaviour of males compared to females in later life. • Investigating the effect of cold temperature stimuli on fear and social behaviour. • More fear of novel environments found in broilers incubated 1 °C lower than advised. • Increased fear of social separation in male broilers incubated such as in nature. [ABSTRACT FROM AUTHOR]

Abstract: Low temperature is one of the most important abiotic factors limiting growth, development and distribution of plants. The effect of cold temperature on phosphorylation and migration of LHCII has been studied by 77K fluorescence emission spectroscopy and immuno-blotting in Arabidopsis thaliana. It has been reported that the mechanism of state transitions has been well operated at optimum growth temperatures. In this study, exposure of leaves to cold conditions (10°C for 180min) along with low light treatment (for 3h) did not show any increase in F726 which corresponds to fluorescence from PSI supercomplex, whereas low light at optimal temperature (26±2°C) could enhanced F726. Therefore these results conclude that low light at cold condition did not enhance PSI absorption cross-section. We have also observed low levels of LHCII phosphorylation in cold exposed leaves in dark or low light. Though LHCII phosphorylation was detectable, the lateral movement of phosphorylated LHCII is reduced due to high granal stacking in cold treated leaves either in light or dark. Apart from these results, it is suggested that increased OJ phase and decreased JI and IP phases of Chl a fluorescence transients were due to reduced electron transport processes in cold treated samples. [Copyright &y& Elsevier]

Attached growth biological treatment systems are a promising solution to ammonia removal in cold-temperature climates. Environmental scanning electron microscopy (ESEM) and confocal laser scanning microscopy in combination with fluorescent in situ hybridization (FISH) was used to investigate the effects of 4 months of exposure to 4 °C on nitrifying biofilm and biomass. These molecular and microscopic methods were modified to minimize loss of mass and distortion of in situ perspectives. Environmental scanning electron microscopy revealed that nitrifying biofilm did not exhibit significant changes in volume with exposure to 4 °C. Confocal laser scanning microscopy in combination with FISH showed that the number of ammonia-oxidizing bacteria (AOB) cells present in the biofilm was statistically consistent during exposure to 4 °C. The RNA content of AOB cells remained sufficient for FISH enumeration. The number of nitrite-oxidizing bacteria cells remained steady during exposure to 4 °C; however, the RNA content of the cells appeared to decrease with exposure to 4 °C, thereby preventing their enumeration using FISH. Water Environ. Res., 84, 328 (2012). [ABSTRACT FROM AUTHOR]

Abstract: Stormwater biofilters have the ability to remove nutrients from stormwater. Reliable pollutant removal during the cold season is particularly important due to the comparably high contamination levels. However, the removal performance might be negatively affected by low temperatures. A biofilter column study was conducted in thermostat-controlled climate rooms (at 2, 7 and 20°C) to investigate the effect of low temperatures on nutrient removal. Phosphorus and suspended solids removal were significantly correlated and consistently very high (typically in excess of 90% and 95%, respectively, at all temperatures). This is important for the successful implementation of biofilters in cold climates since phosphorus is commonly of principal concern, often being the limiting factor for eutrophication in freshwater ecosystems. Unfortunately, nitrogen removal was poor and leaching was shown, which increased with temperature. The increasing nitrate–nitrogen production rates with temperature were well described by the Arrhenius relationship with temperature coefficients Q 10 in the range which is typically used to describe temperature effects on nitrification. Thus, temperature effects have to be considered when nitrogen removal is targeted and the biofilter might be exposed to cold temperatures. [ABSTRACT FROM AUTHOR]

A mobile testing center was installed at a lagoon wastewater treatment plant (WWTP) at Terrebonne, Canada to investigate the rate of ammonia removal of attached growth treatment systems at 4°C and at low influent carbon concentrations. The testing center housed two laboratory-scale reactors, a pilot-scale BioStyr system (Veolia Water) and a pilot-scale moving bed bioreactor (MBBR) system (Veolia Water). Although the rates of laboratory-scale and the pilot-scale systems demonstrated that the exposure time to low temperature has a significant effect on the kinetics of the system, the ammonia removal rates of all the systems were shown to be significant at 4°C. A strong correlation was demonstrated between the rates of ammonia removal produced by the laboratory-scale reactors, the pilot BioStyr system and pilot MBBR system; thus verifying the scale-up capability of the laboratory-scale reactors and demonstrating that nitrifiers can achieve ammonia removal under cold temperature conditions for elapsed periods of time independent of the reactor design. Finally, the ammonia removal rates of the laboratory-scale systems, the BioStyr pilot system, and the MBBR pilot system were all accurately predicted by a recently proposed Theta model. [ABSTRACT FROM AUTHOR]

Abstract: An icephobic surface is always desirable for high voltage overhead transmission lines to reduce ice formation on their aluminum surface, especially in a low temperature and high humidity environment. This work studied the effects of two hydrophobic coatings when applied on aluminum surfaces under cold and raining conditions in an artificial climatic chamber. Compared with bare hydrophilic aluminum surfaces, the aluminum surfaces coated with hydrophobic room temperature vulcanized silicone rubber (RTV SR) did resist ice formation but was covered by a layer of ice after 30min of spraying supercooled water. However, a superhydrophobic coating can largely prevent ice formation on the surface except a few ice growth spots at a working temperature of −6°C. Furthermore, such coating keeps average water contact angles larger than 150° even at a working temperature of −10°C. This highly icephobic performance of the above samples is mainly attributed to the superhydrophobic property of the coating, which was obtained on micronanoscale structured aluminum surfaces after the low surface-energy stearic acid treatment. [Copyright &y& Elsevier]

The rate of nitrification within a laboratory-scale Biological Aerated Filtration treatment system at 4°C was investigated during an exposure time of approximately four months (acclimatized experiments). In addition, shock experiments from 20°C to 4°C and from 4°C to 20°C were performed. The acclimatized experiments demonstrated that the exposure time the system remained at low temperature strongly affects the rates of nitrification. Nevertheless, the experiments showed that significant nitrification rates are maintained for up to 115 days at 4°C. The rate of ammonia removal after an exposure time of 115 days at 4°C was shown to be as high as 16% of the rate of removal observed at 20°C. The 20°C to 4°C shock experiment demonstrated a 56% decrease in the rate of ammonia removal. On the other hand, the 4°C to 20°C shock experiment demonstrated an increase in the relative rates of ammonia removal of up to 300% when compared to rates of removal measured after 115 days at 4°C. Thus, although the rates of nitrification have been shown to decrease significantly as a function of exposure time at 4°C, the process has demonstrated important rates of ammonia removal at 4°C for the approximate span of the North American winter. [ABSTRACT FROM AUTHOR]

Abstract: Though microbial activity is known to occur in frozen soils, little is known about the fate of animal manure N applied in the fall to agricultural soils located in areas with prolonged winter periods. Our objective was to examine transformations of soil and pig slurry N at low temperatures. Loamy and clay soils were either unamended (Control), amended with 15NH4-labeled pig slurry, or amended with the pig slurry and wheat straw. Soils were incubated at −6, −2, 2, 6, and 10 °C. The amounts of NH4, NO3 and microbial biomass N (MBN), and the presence of 15N in these pools were monitored. Total mineral N, NO3 and 15NO3 increased at temperature down to −2 °C in the loam soil and −6 °C in the clay soil, indicating that nitrification and mineralization proceeded in frozen soils. Nitrification and mineralization rates were 1.8–4.9 times higher in the clay than in the loamy soil, especially below freezing point (3.2–4.9), possibly because more unfrozen water remained in the clay than in the loamy soil. Slurry addition increased nitrification rates by 3–14 times at all temperatures, indicating that this process was N-limited even in frozen soils. Straw incorporation caused significant net N immobilization only at temperatures ≥2 °C in both soils; the rates were 1.4–3.4 higher in the loam than in the clay soil. Nevertheless, up to 30% of the applied 15N was present in MBN at all temperatures. These findings indicate that microbial N immobilization occurred in frozen soils, but was not strong enough to induce net immobilization below the freezing point, even in the presence of straw. The Q 10 values for estimated mineralization and nitrification rates were one to two orders-of-magnitude larger below 2 °C than above this temperature (13–208 versus 1.5–6.9, respectively), indicating that these processes are highly sensitive to a small increase in soil temperature around the freezing point of water. This study confirms that net mineralization and nitrification can occur at potentially significant rates in frozen agricultural soils, especially in the presence of organic amendments. In contrast, net N immobilization could be detected essentially above the freezing point. Our results imply that fall-applied N could be at risk of overwinter losses, particularly in fine-textured soils. [Copyright &y& Elsevier]

Isolated sympathetic ganglia from various mammalian species fire spontaneous, rhythmic discharge when exposed to low temperatures. Extracellular recording from rat, guinea pig, and rabbit superior cervical ganglia as well as dog lumbar ganglion revealed large single potentials or bursts of potentials, occurring at regular intervals, when the bath temperature was kept between 15-30°C. When the temperature was reduced below 15°C or raised above 30°C, the rhythmic discharge decreased in frequency and finally stopped. Rhythmic discharge also appeared when ganglia were treated with emetine or the K+ channel blockers, cesium and 4-aminopyridine. The frequency and amplitude of potentials and the pattern of rhythm varied from ganglion to ganglion. The single potential or rhythmic burst firing seemed to originate from a single unit or multiple discharging units, as indicated by the amplitude and frequency of the potentials in a burst. The discharge was abolished by ganglionic blocking agents or by the absence of Ca2+, suggesting a presynaptic origin. The spontaneous rhythmic discharge may be important as a support mechanism for the cardiovascular system in victims of exposure to extreme cold temperature. [ABSTRACT FROM AUTHOR]

Abstract: Rice is a major source of food for more than 2.7 billion people and planted on nearly 130 million hectares in which 10% is subjected to low temperature problems. Dry season (DS) rice cropping has been expanding in the high altitude lands in Asia and the low temperature is one of constraints to rice production. This study aims to quantify the potential for growing irrigated rice in DS, particularly in high altitude areas in northern Lao PDR where temperatures are low and pose problems for seedling establishment. Research focused on identifying sowing times to avoid the detrimental effects of low temperature, the optimal seedling age for transplanting, the potential of plastic covers and half burnt paddy husk layer to protect nursery seedbeds from low temperature and varieties suitable for this environment. Studies were conducted over 5 years and were examined at six locations. In two locations, where temperature was favorable for rice production throughout the DS, time of sowing was not critical. In higher altitude areas in northern Lao PDR, however, low temperature caused establishment problems in nurseries. In these areas, mid-November sowing before the onset of winter reduced the low temperature effects on seedling establishment while sowing in mid winter (December and January) increased the risk of failure. There were no significant effects of seedling age (25-, 35- and 45-day old) for transplanting on yield for DS rice. Using clear plastic to cover the nursery increased minimum temperatures on average by about 4°C, which improved seedling growth and resulted in higher grain yield. The mean minimum temperature of 12°C for 30 days after seeding is critical and temperature below 12°C resulted in high risk of crop failure due to poor germination, poor seedling growth or insufficient seedlings. Rice needs to be sown at times where the mean minimum temperature exceeds 12°C or plastic covers are required to protect seedlings. The current popular varieties did not show significant tolerance to extreme cold temperature. [Copyright &y& Elsevier]

Methyl jasmonate (MeJA) has recently been shown to act as a plant-to-bacteria signal. We tested the hypothesis that pre-induction of Rhizobium leguminosarum bv. phaseoli cells with genistein and/or MeJA would at least partially overcome the negative effects of low root zone temperature (RZT) on bean nodulation, nitrogen fixation and plant growth. Otebo bean plants were grown at constant air temperature (25 o C) and two RZT regimes (25 and 17 o C) and inoculated with R. leguminosarum bv. phaseoli pre-induced with MeJA and/or genistein. Our results indicate that low RZT inhibited nodulation, nitrogen fixation and plant growth. The plants growing at low RZT began fixing nitrogen seven days later compared to those at higher RZT. The low RZT plants had fewer nodules, lower nodule weight, less N fixation, slower plant growth, fewer leaves, smaller leaf area, and less dry matter accumulation comared to plants at a higher RZT. Rhzobium leguminosarum bv. phaseoli cells induced with genistein and/or MeJA enhanced bean nodulation, nitrogen fixation and growth at both optimum and suboptimum RZTs. The results of this study indicate that MeJA improves bean nitrogen fixation and growth at both optimum and suboptimum RZTs, and can be used alone or in combination with genistein to partially overcome the low RZT induced inhibitory effects on nodulation and nitrogen fixation. [ABSTRACT FROM AUTHOR]

Palinkas, L. A., Mäkinen, T. M., Pääkkönen, T., Rintamäki, H., Leppäluoto, J.&Hassi, J. (2005). Influence of seasonally adjusted exposure to cold and darkness on cognitive performance in circumpolar residents.Scandinavian Journal of Psychology,46, 239–246.The effects of seasonally adjusted 24-h exposure to cold and darkness on cognitive performance in urban circumpolar residents was assessed in 15 male subjects who spent three 24-h periods in a climatic chamber at 65° latitude during the winter (January–March) and/or summer (August–September). Each subject was exposed to three different environmental conditions in random order: (1) 22°C temperature and 500 lx lighting; (2) 10°C temperature and 500 lx lighting; and (3) 10°C temperature and 0.5–l lx lighting. Accuracy on an addition-subtraction task was significantly greater in the summer than in the winter (p= 0.038), while accuracy on a repeated acquisition task was significantly greater in the winter than in the summer (p<0.001). Independent of season, exposure to cold and darkness was significantly associated with a decline in response time on five cognitive tests, an improvement in accuracy on three tests measuring complex cognitive tasks, and a decline in accuracy on two tests measuring simple tasks. Increased performance on complex tasks may result from increased arousal in response to the combination of cold temperatures and dim light characteristic of the winter in urban circumpolar settings. [ABSTRACT FROM AUTHOR]

Constructed wetland (CW), a robust eco-technology used for wastewater reclamation can be considered as an ideal synergism among water security, energy harvesting and environmental services. The technology as an alternative to existing energy and chemical intensive treatments has attained maturity for treating contaminants from range of waste streams, under wide range of climates and conditions. Recent trend shows additional research interventions for better expansion of the technology such as energy harvesting to make the system a net energy producer by coupling CW to microbial fuel cell (CW-MFC) and improved operation under climatically challenged condition. The assessment discusses treatment efficiency, bioelectricity production, improved electrode efficiency, performance variation w.r.t. Macrophyte, emerging pollutant removal and microbial community structure in CW-MFC, which reveal that carefully designed integrated CW-MFC with optimized system elements (electrode, spacing, separator, macrophyte, C source, rhizosphere microbes) are necessary for its more profitable futuristic application. Further, low temperature challenges of the technology and the strategies to achieve satisfactory low temperature performance were assessed. Successful implementation of the technology in cold climate calls for design of CW with incorporation of appropriate heat preservation method, active macrophyte or microbial consortia to work effectively under low temperature. Comparative evaluation of the technology with other treatment processes using Life cycle assessment (LCA) with cradle to grave approach (considering alternative substrates, energy harvesting, macrophyte use and disposal options) would further boost the technology penetration. Potential research areas that appear to be worth pursuing in future to obtain further gains in CW performance are also discussed. • An optimally designed CW represents a robust multifaceted treatment system for wastewater. • Well-designed CW with heat preservation measures would help its expansion in cold. • CW-MFC as an energy efficient wastewater treatment option should be exploited further. • LCA application on CW including end use of by-product will make the technology more sustainable. [ABSTRACT FROM AUTHOR]

Growth of Listeria monocytogenes in cold temperatures coupled with its tolerance of antimicrobials can promote its survival and persistence in food processing environments. The food industry relies heavily on cleaning and sanitation to control L. monocytogenes ; therefore, it is important to understand the environmental context (i.e., temperature) on the efficacy of antimicrobials used in food industry. The minimum bactericidal concentrations (MBCs) of an "eco-friendly" citric acid-based (CAB) sanitizer and a conventional quaternary ammonium compound (CQAC) sanitizer were determined against 14 L. monocytogenes isolates at 4–30 °C. A subset of isolates (n = 3) was also exposed to sub-lethal concentrations of sanitizers to assess differences in growth behavior. CAB and CQAC were effective at manufacturer recommended concentrations in liquid assays. The MBC of CAB was significantly lower at 4 °C compared to 23 °C (p < 0.05), whereas the MBC of CQAC was unchanged between 4 °C and 23 °C. Manufacturers' recommendations for dose and duration of CAB and CQAC were unable to consistently achieve a >5-log reduction of L. monocytogenes attached to surfaces. Findings from this study demonstrate the importance of sanitizer evaluation under conditions representative of their use in the food industry. • Sanitizers inactivated L. monocytogenes at manufacturer concentrations in liquid media. • Quaternary ammonium compound (QAC) sanitizers remain inhibitory at high dilutions. • Commercial-QAC minimum bactericidal concentrations were unaffected by low temperature. • Consistent 5-log reduction was not observed for any sanitizer for attached cells. [ABSTRACT FROM AUTHOR]