The long-term (142 years) spatiotemporal reconstruction and synoptic analysis of extreme low temperatures (− 15 °C or lower) in the northwest region of Iran

Author(s):  
Mehdi Aalijahan ◽  
Anthony R. Lupo ◽  
Bromand Salahi ◽  
Yusef Ghavidel Rahimi ◽  
Manuchehr Farajzadeh Asl
Author(s):  
Kyungpyo Hong ◽  
Stephanie Nadya Sutanto ◽  
Jeong A. Lee ◽  
Jongsup Hong

Ni–Rh and Ni–Co nano-scale alloys exhibit high methane conversion, hydrogen yield, resistance to carbon formation, and long-term stability at low temperatures, allowing them to cope with the various operating conditions of direct methane-fueled PCFCs.


2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Olayinka S. Ohunakin ◽  
Muyiwa S. Adaramola ◽  
Olanrewaju M. Oyewola ◽  
Richard L. Fagbenle ◽  
Fidelis I. Abam

Computer simulation of buildings and solar energy systems are being used increasingly in energy assessments and design. This paper evaluates the typical meteorological year (TMY) for Sokoto, northwest region, Nigeria, using 23-year hourly weather data including global solar radiation, dew point temperature, mean temperature, maximum temperature, minimum temperature, relative humidity, and wind speed. Filkenstein-Schafer statistical method was utilized for the creation of a TMY for the site. The persistence of mean dry bulb temperature and daily global horizontal radiation on the five candidate months were evaluated. TMY predictions were compared with the 23-year long-term average values and are found to have close agreement and can be used in building energy simulation for comparative energy efficiency study.


Author(s):  
V.M. Yezhov ◽  
◽  
V.I. Dubrovskyi ◽  
O.Yu. Ansieiev ◽  
O.A. Olenich ◽  
...  

The authors present the results of the collection’s formation of some ornamental shrubs, long-term phenological observations of them and the selection of the best forms and breeding hybrids in the Left-Bank Lisosteppe of Ukraine. In particular, the characteristic of the vegetation of 20 varieties of common lilac collection is given. The estimation of the terms and duration of the crop flowering enable to divide its varieties into groups of early, average and late flowering. The high decorative value of most of the strains has been described as well as their resistance to low temperatures and pests. The additional analysis of the latest literature data has shown the significant yield of aromatic substances in the common lilac plant, with the predominance of alkanes and lilac alcohol. The results have been presented of 70 rose cultivars of adaptation to the growing zone conditions. There are 20 promise varieties of the crop, which are characterized by high decorative value, resistance to pathogens and low temperatures and duration of flowering. The characteristics of the new variety of roses of the floribunda group – Olexandra has been given created by the authors. Along side with the high decorative value, different types of the rose plant provide the significant yield of aromatic substances with the domination of alkanes, monoterpenes and 2-phenylethanol. The analysis of the literature data also has shown the presence of aromatic substances in the jasmine and mock-orange plants. The first is characterized with esters based on benzene, cis-jasmon and isophytol, the second – with some sesquiterpenes and epi-13-manol. The further research included the phenological evaluation of the of white cedar and juniper collection. The best selected forms were characterized with decorativeness, resistance to frost, pests and pathogens. The literature data have shown, that the aromatic complex of the crops cultures includes mainly monoterpenes and their derivatives – alcohols and ketones. As a result, it was concluded that it is necessary to expand research with ornamental bushy crops in the direction of evaluating of their aromatic properties.


Author(s):  
S. Papavinasam ◽  
A. Doiron ◽  
T. Panneerselvam ◽  
Y. Lafrenie`re ◽  
M. Attard ◽  
...  

The design of coatings must be adequate to protect pipelines under long-term, severe environmental conditions, including the extreme climatic conditions that will apply in the North before the pipe is installed and operation begins. Practices and standardised methodologies for evaluating and qualifying pipeline coatings for application in northern pipelines are discussed. Results from laboratory and field experiments, carried out under the conditions to which coatings will be exposed during construction, are presented. Based on 1-year laboratory experiments in which samples were exposed to temperatures as low as −45°C and limited data from the field experiments, it is concluded that Canadian Standards Association (CSA) standards CSA Z662, CSA Z245.20 and CSA Z245.21 adequately cover evaluation of coatings for northern pipelines. However, in order to evaluate the effects of low-temperatures, the specimens should be exposed for at least 4 months. Coatings qualified by CSA Z245.21 (System B1 and B2) are less affected from exposure to low-temperatures than those qualified by CSA Z245.21 (System A1) and CSA Z245.20.


2019 ◽  
Vol 128 (3) ◽  
pp. 725-734
Author(s):  
Yasuko Kawakami ◽  
Kazuo Yamazaki ◽  
Kazunori Ohashi

Abstract Phenotypic polymorphisms are found in a wide array of taxa, and unravelling the mechanisms that maintain them is of great interest to evolutionary and ecological biologists. Temporal environmental heterogeneity may play a role in the maintenance of polymorphisms but is poorly understood. In the present study, we analysed trends in intergenerational elytral colour morph frequencies in relation to changes in fitness and life history traits (i.e. body size, mortality, fecundity, hatching rate and mate preference) in the ladybird beetle Cheilomenes sexmaculata (Coleoptera: Coccinellidae). A long-term field survey spanning nine years showed that the frequency of dark morphs increases over winter and then decreases in spring. Dark morphs may have an advantage in winter due to their higher tolerance of low temperatures compared with light morphs. Light-morph females were heavier in winter than dark-morph females. They also mated more frequently and had higher hatching rates, potentially causing an increase in light morphs in spring. These results suggest that fluctuations in morph frequencies resulting from the conflicting directions of selection pressures between overwintering and spring generations may help to maintain genetic polymorphism.


2009 ◽  
Vol 75 (23) ◽  
pp. 7310-7318 ◽  
Author(s):  
Nabila Haddad ◽  
Christopher M. Burns ◽  
Jean Michel Bolla ◽  
Hervé Prévost ◽  
Michel Fédérighi ◽  
...  

ABSTRACT Campylobacter jejuni is a leading cause of bacterial gastroenteritis worldwide. Infection generally occurs after ingestion of contaminated poultry products, usually conserved at low temperatures. The mechanisms promoting survival of C. jejuni in the cold remain poorly understood despite several investigations. The present study provides insight into the survival mechanism by establishing the involvement of polynucleotide phosphorylase (PNPase), a 3′-5′ exoribonuclease with multiple biological functions in cold survival. The role of PNPase was demonstrated genetically using strains with altered pnp genes (which encode PNPase) created in C. jejuni F38011 and C. jejuni 81-76 backgrounds. Survival assays carried out at low temperatures (4 and 10°C) revealed a difference of 3 log CFU/ml between the wild-type and the pnp deletion (Δpnp) strains. This did not result from a general requirement for PNPase because survival rates of the strains were similar at higher growth temperatures (37 or 42°C). trans-Complementation with plasmid pNH04 carrying the pnp gene under the control of its natural promoter restored the cold survival phenotype to the pnp deletion strains (at 4 and 10°C) but not to the same level as the wild type. In this study we demonstrate the role of PNPase in low-temperature survival of C. jejuni and therefore attribute a novel biological function to PNPase directly related to human health.


1978 ◽  
Vol 56 (17) ◽  
pp. 2119-2123 ◽  
Author(s):  
Douglas W. Larson

The effect of prolonged frozen storage on patterns of photosynthesis and respiration in the lichen Alectoria ochroleuca (Hoffm.) Massal. has been examined. The results indicate that this plant not only survives long-term exposure to low temperatures but also that its basic photosynthetic and respiratory responses to temperature, light intensity, and thallus moisture content are altered very little by long-term storage at −60 °C. This maintenance not only of absolute viability but also of the more subtle patterns of physiological activity suggests that such storage may be used to hold lichen material for use in multivariate experimental systems which require replicates having identical field pretreatment.


Author(s):  
Yingying Qiao ◽  
Oleksandr Kyselov ◽  
Changzhong Liu

The experiment aims to study the effects of long-term relatively high and low temperatures on growth performance and meat quality of broiler chickens. The experiment was carried out in Yunnan Academy of Animal Science, for determine the quality of meat used the laboratories of Henan Institute of Science and Technology. A total of experiment use 240 healthy 1-day-old Avian broiler chickens were randomly divided into three groups: relatively high temperature group, low temperature group and control group. The results of the experiment confirm that at low temperatures, when the energy consumption of the animal decreases, it leads to weight loss, which we can see in the low-temperature group, the average daily weight gain in this experiment was significantly lower than in the control group (P <0.05). It was found that low-temperature stress significantly increased the mortality of broilers, at the age of 42 days in the low-temperature group, the mortality of chickens was higher than in the control group, by 71.4%. Among all evaluated groups on the content of unsaturated fatty acids SFA, PUFA, MUFA and EFA in the muscles of the breasts of broilers, the lowest content was in the lower temperature group than in the control group, by 48.3%, 46.9%, 51.5% and 43.9%. Studies have shown that influence of high-temperature above 30°C causes disturbances in poultry behavior and physiology, leading to reduced production performance. Broilers aged 35-40 days experienced 31°C high-temperature stress and found that their performance and immunity decreased. Broilers feed intake and growth rate at 35°C high temperature were reduced by 13% and 32% than at 20°C. The results showed that: ① Relatively high temperature and low temperature for a long time reduced the growth performance and mortality of broilers, and long-term relatively low temperature decreased the slaughter performance of broilers.② Relatively high and low temperatures for a long period of time reduced the levels of serine, glycine, SFA, PUFA, USFA, EFA and MUFA in broiler breast muscles negative effect on meat quality. ③ The long-term relatively low temperature has a greater adverse effect on broilers than the long-term relatively high temperature. The results provided some theoretical basis for accurately setting the broiler breeding environment temperature, improving broiler quality, maximizing broiler production performance, and increasing the economic benefits of the farm.


Author(s):  
Miao Zhang ◽  
Guofang Wu ◽  
Lei Wang ◽  
Bei Zhang ◽  
Jun Chen ◽  
...  

Abstract Background Silages, as a nutritious and long-term preserved fodder, is achieved through fermentation. However, the constant low temperatures and freeze–thaw event are key factors that affect the quality of silages due to low levels of lactic acid production and undesirable microbial community revitalization. In this study, we attempt to investigate the effects of Lactobacillus plantarum QZW5 on the fermentation characteristics of wheat silage under ensiling conditions at the order of the following temperatures: constant low temperatures (5 °C for 30 days), multigelation (10 ℃ at day and – 10 ℃ at night for 30 days) and room temperature (aerobic/anaerobic, 10 days). Results Under multigelation condition, Lactobacillus plantarum QZW5 inoculation significantly increased the contents of lactic acid and acetic (P < 0.05) in the silage. The pH, bacterial richness index (Chao) and diversity index (Shannon) of the silage were significantly decreased by Lactobacillus plantarum QZW5 (P < 0.05). In Lactobacillus plantarum QZW5 inoculated silage, the dominant genera were L. plantarum subsp. plantarum. However, those in the control silage were Leuconostoc mesenteroides and Leuconostoc fallax. LAB (lactic acid bacteria) inoculation increased the abundance of desirable Lactobacillus spp. and inhibited the growth of undesirable Escherichia coli, Saccharomyces cerevisiae, and Filamentous fungi, among others in the silage. Conclusions Therefore, inoculation of L. plantarum QZW5 during ensiling could stimulate favorable fermentation and reconstruct bacterial community for better silage preservation. Graphic abstract


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