Resistance of Species of the Drosophila Melanogaster Subgroup to Environmental Extremes.

1980 ◽  
Vol 28 (3) ◽  
pp. 413 ◽  
Author(s):  
SM Stanley ◽  
PA Parsons ◽  
GE Spence ◽  
L Weber

Resistance to the extreme stresses of high temperature-desiccation and low temperature were compared among six species of the melanogaster species subgroup of Drosophila. D. melanogaster was the most resistant to all stresses. The cosmopolitan species, D. melanogaster and D. simulans, were more resistant to cold stresses than the four endemic species, D. mauritiana, D. teissieri, D. yakuba and D. erecta. D. simulans, D. mauritiana and D. teissieri showed similar resistance to heat and desiccation, while D. yakuba and especially D. erecta were sensitive to these stresses. A prerequisite for the spread of the cosmopolitan species into temperate zones thus appears to have involved a level of resistance to cold stress exceeding that of the endemics. A greater resistance to heat and desiccation stresses, such as that found in D. melanogaster, may also be necessary for the invasion of more extreme environments. All species with the exception of D. erecta and to a lesser extent D. yakuba can survive 6 h at the extreme temperature of 34�C at 95% RH, and in addition most of those flies surviving stresses of this type are fertile. This suggests that these species can survive short stress periods in a humid microhabitat in the wild.

Author(s):  
Junhyeong Lee ◽  
Wanhyung Lee ◽  
Won-Jun Choi ◽  
Seong-Kyu Kang ◽  
Seunghon Ham

Exposure to extreme temperature is a critical occupational risk factor. This study aimed to investigate the association between exposure to extreme temperatures and injury at the workplace using data from 92,238 workers (46,175 male and 46,063 female) from the 2014 and 2017 Korean Working Condition Survey. Exposure to extremely high or low temperatures, injury experiences, and personal protective equipment (PPE) wearing behavior were investigated using a questionnaire. Logistic regression analyses were performed to investigate the association between exposure to extreme temperature and injury experience. The association between injury experience and PPE wearing behavior was analyzed for each exposure group. After adjusting for individual and occupational factors, the odds ratios (ORs) for injury experience were 2.06 (95% confidence interval (CI): 1.78–2.38) and 1.64 (95% CI: 1.44–1.85) in both high and low temperature exposure groups, respectively, and 1.45 (95% CI: 1.15–1.83) for those not wearing PPE when exposed to high temperature. There was no significant association shown with wearing PPE and injury experience in the low temperature exposure group. Exposure to extreme temperature tended to increase the risk of injury, and was higher in workers not wearing PPE in high temperature. PPE that can be worn comfortably in high temperature is needed to prevent occupational injury.


PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2376 ◽  
Author(s):  
Amy M. Savage ◽  
Justin Hills ◽  
Katherine Driscoll ◽  
Daniel J. Fergus ◽  
Amy M. Grunden ◽  
...  

High-throughput sequencing techniques have opened up the world of microbial diversity to scientists, and a flurry of studies in the most remote and extreme habitats on earth have begun to elucidate the key roles of microbes in ecosystems with extreme conditions. These same environmental extremes can also be found closer to humans, even in our homes. Here, we used high-throughput sequencing techniques to assess bacterial and archaeal diversity in the extreme environments inside human homes (e.g., dishwashers, hot water heaters, washing machine bleach reservoirs, etc.). We focused on habitats in the home with extreme temperature, pH, and chemical environmental conditions. We found a lower diversity of microbes in these extreme home environments compared to less extreme habitats in the home. However, we were nonetheless able to detect sequences from a relatively diverse array of bacteria and archaea. Habitats with extreme temperatures alone appeared to be able to support a greater diversity of microbes than habitats with extreme pH or extreme chemical environments alone. Microbial diversity was lowest when habitats had both extreme temperature and one of these other extremes. In habitats with both extreme temperatures and extreme pH, taxa with known associations with extreme conditions dominated. Our findings highlight the importance of examining interactive effects of multiple environmental extremes on microbial communities. Inasmuch as taxa from extreme environments can be both beneficial and harmful to humans, our findings also suggest future work to understand both the threats and opportunities posed by the life in these habitats.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Dongzhen Chen ◽  
Hua Lu ◽  
Shengyang Zhang ◽  
Jia Yin ◽  
Xuena Liu ◽  
...  

Abstract Background The effects of extreme temperature on infectious diseases are complex and far-reaching. There are few studies to access the relationship of pulmonary tuberculosis (PTB) with extreme temperature. The study aimed to identify whether there was association between extreme temperature and the reported morbidity of PTB in Shandong Province, China, from 2005 to 2016. Methods A generalized additive model (GAM) was firstly conducted to evaluate the relationship between daily reported incidence rate of PTB and extreme temperature events in the prefecture-level cities. Then, the effect estimates were pooled using meta-analysis at the provincial level. The fixed-effect model or random-effect model was selected based on the result of heterogeneity test. Results Among the 446,016 PTB reported cases, the majority of reported cases occurred in spring. The higher reported incidence rate areas were located in Liaocheng, Taian, Linyi and Heze. Extreme low temperature had an impact on the reported incidence of PTB in only one prefecture-level city, i.e., Binzhou (RR = 0.903, 95% CI: 0.817–0.999). While, extreme high temperature was found to have a positive effect on reported morbidity of PTB in Binzhou (RR = 0.924, 95% CI: 0.856–0.997) and Weihai (RR = 0.910, 95% CI: 0.843–0.982). Meta-analysis showed that extreme high temperature was associated with a decreased risk of PTB (RR = 0.982, 95% CI: 0.966–0.998). However, extreme low temperature was no relationship with the reported incidence of PTB. Conclusion Our findings are suggested that extreme high temperature has significantly decreased the risk of PTB at the provincial levels. The findings have implications for developing strategies to response to climate change.


2013 ◽  
Vol 2013 (1) ◽  
pp. 000951-000956 ◽  
Author(s):  
Hannes Greve ◽  
F. Patrick McCluskey

Low Temperature Transient Liquid Phase Sintering (LT-TLPS) enables the formation of joints robust to high temperatures at low process temperatures. TLPS systems consist of one or more low temperature constituents (i.e. Sn) and one or more high temperature constituents (i.e. Cu). The sinter joints are formed by intermetallic compound formation between these constituents. In this paper a paste based LT-TLPS approach is demonstrated. The organic binders and fluxes used to mix the pastes prevent the metal particles from oxidation and facilitate a vacuum-free process in air without the need of a reducing atmosphere. Pastes based on the Cu-Sn system have been developed enabling a completely pressure-less process. Furthermore sinter pastes for LT-TLPS at low pressure (<0.5MPa) applied during the initial stage of the sintering process have been developed which form almost void free joints. To assess the strength of the sintered joints a high-temperature shear fixture has been designed. Shear tests have been performed at 25°C, 400°C, and 600°C to characterize the influence of high temperature conditions on the joint performance. The shear strength of the joints formed without pressure has been assessed for different Cu-to-Sn ratios at all temperature levels. It is shown that the maximum application temperature and shear strength depends on the ratio of low melting temperature and high melting temperature constituents. The pastes introduced here can be used to form joints resilient to application temperatures of up to 600°C. They show the potential to form joints for reliable operation under extreme temperature conditions.


2016 ◽  
Author(s):  
Amy M. Savage ◽  
Justin Hills ◽  
Katherine Driscoll ◽  
Daniel J Fergus ◽  
Amy M Grunden ◽  
...  

Background: High throughput sequencing techniques have opened up the world of microbial diversity to scientists, and a flurry of studies in the most remote and extreme habitats on earth have begun to elucidate the key roles of microbes in ecosystems with extreme conditions. These same environmental extremes can also be found closer to humans; in fact, they can be found in our homes. Here, we used high throughput sequencing techniques to assess microbial diversity in the extreme environments inside human homes (e.g. dishwashers, hot water heaters, washing machine bleach reservoirs, etc.). We focused on habitats in the home with extreme temperature, pH and chemical environmental conditions. Results: We found that although these habitats supported a lower diversity of microbes than less extreme habitats in the home, there were still diverse microbial assemblages in extreme home environments. Habitats with extreme temperatures alone appeared to be able to support a greater diversity of microbes than habitats with extreme pH or extreme chemical environments alone. Microbial diversity was lowest when habitats had both extreme temperature and one of these other extremes. This interactive effect was strongest when habitats had both extreme temperatures and extreme pH. Under these conditions, taxa with known associations with extreme conditions dominated. Conclusions: Our findings highlight the importance of examining interactive effects of multiple environmental extremes on microbial communities. Inasmuch as taxa from extreme environments can be both pathogens and industrially useful, our findings also suggest future work to understand both the threats and opportunities posed by the life in these habitats.


2021 ◽  
Vol 3 (12) ◽  
Author(s):  
Xueyuan Kuang ◽  
Danqing Huang ◽  
Ying Huang

AbstractIncreasingly extreme temperature events under global warming can have considerable impacts on sectors such as industrial activities, health, and transportation, suggesting that risk for these kinds of events under climate change and its regional sensitivity should be reassessed. In this study, the observation and multi-model simulations from CMIP6 are comprehensively used to explore the regional differences of the extreme temperature response to climate change from the perspective of return period (RP). The Gumbel model of generalized extremum distribution is applied to estimate the RP for the annual extremum of temperature based on Gaussian distribution of daily temperature. The analysis on the observation in selected three sites indicates that the regional inconsistency of RP variation is not only existed in extreme high temperature (HTx) but also in low temperature (LTn) during the past several decades. The annual amplitude of temperature extremum in the Northeast China is enlarged with summer becoming hotter and winter becoming colder while the opposite situation is detected in Huang-Huai River Basin with cooler summer and relatively stable winter, and South China is characterized by hotter summer and slight warmer winter. From the spatial distribution of the HTx and LTn variations of fix RP, it is found that the Northeast China and Jiang-Huai River Basin is the most sensitive areas, respectively, in the response of extreme low temperature and high temperature to global warming. However, the regional inconsistency of the extreme temperature change is only observed under SSP1-2.6 scenario in the CMIP6 simulation but gradually disappeared from SSP2-4.5 to SSP5-8.5.


2016 ◽  
Author(s):  
Amy M. Savage ◽  
Justin Hills ◽  
Katherine Driscoll ◽  
Daniel J Fergus ◽  
Amy M Grunden ◽  
...  

High throughput sequencing techniques have opened up the world of microbial diversity to scientists, and a flurry of studies in the most remote and extreme habitats on earth have begun to elucidate the key roles of microbes in ecosystems with extreme conditions. These same environmental extremes can also be found closer to humans, even in our homes. Here, we used high throughput sequencing techniques to assess bacterial and archaeal diversity in the extreme environments inside human homes (e.g., dishwashers, hot water heaters, washing machine bleach reservoirs, etc.). We focused on habitats in the home with extreme temperature, pH and chemical environmental conditions. We found a lower diversity of microbes in these extreme home environments compared to less extreme habitats in the home. However, we were nonetheless able to detect sequences from a relatively diverse array of bacteria and archaea. Habitats with extreme temperatures alone appeared to be able to support a greater diversity of microbes than habitats with extreme pH or extreme chemical environments alone. Microbial diversity was lowest when habitats had both extreme temperature and one of these other extremes. In habitats with both extreme temperatures and extreme pH, taxa with known associations with extreme conditions dominated. Our findings highlight the importance of examining interactive effects of multiple environmental extremes on microbial communities. Inasmuch as taxa from extreme environments can be both beneficial and harmful to humans, our findings also suggest future work to understand both the threats and opportunities posed by the life in these habitats.


2016 ◽  
Author(s):  
Amy M. Savage ◽  
Justin Hills ◽  
Katherine Driscoll ◽  
Daniel J Fergus ◽  
Amy M Grunden ◽  
...  

High throughput sequencing techniques have opened up the world of microbial diversity to scientists, and a flurry of studies in the most remote and extreme habitats on earth have begun to elucidate the key roles of microbes in ecosystems with extreme conditions. These same environmental extremes can also be found closer to humans, even in our homes. Here, we used high throughput sequencing techniques to assess bacterial and archaeal diversity in the extreme environments inside human homes (e.g., dishwashers, hot water heaters, washing machine bleach reservoirs, etc.). We focused on habitats in the home with extreme temperature, pH and chemical environmental conditions. We found a lower diversity of microbes in these extreme home environments compared to less extreme habitats in the home. However, we were nonetheless able to detect sequences from a relatively diverse array of bacteria and archaea. Habitats with extreme temperatures alone appeared to be able to support a greater diversity of microbes than habitats with extreme pH or extreme chemical environments alone. Microbial diversity was lowest when habitats had both extreme temperature and one of these other extremes. In habitats with both extreme temperatures and extreme pH, taxa with known associations with extreme conditions dominated. Our findings highlight the importance of examining interactive effects of multiple environmental extremes on microbial communities. Inasmuch as taxa from extreme environments can be both beneficial and harmful to humans, our findings also suggest future work to understand both the threats and opportunities posed by the life in these habitats.


Author(s):  
Sida Liu ◽  
Emily Yang Ying Chan ◽  
William Bernard Goggins ◽  
Zhe Huang

(1) Background: The adverse health effect associated with extreme temperature has been extensively reported in the current literature. Some also found that temperature effect may vary among the population with different socioeconomic status (SES), but found inconsistent results. Previous studies on the socioeconomic vulnerability of temperature effect were mainly achieved by multi-city or country analysis, but the large heterogeneity between cities may introduce additional bias to the estimation. The linkage between death registry and census in Hong Kong allows us to perform a city-wide analysis in which the study population shares virtually the same cultural, lifestyle and policy environment. This study aims to examine and compare the high and low temperature on morality in Hong Kong, a city with a subtropical climate and address a key research question of whether the extreme high and low temperature disproportionally affects population with lower SES. (2) Methods: Poisson-generalized additive models and distributed-lagged nonlinear models were used to examine the association between daily mortality and daily mean temperature between 2007–2015 with other meteorological and confounding factors controlled. Death registry was linked with small area census and area-level median household income was used as the proxy for socioeconomic status. (3) Results: 362,957 deaths during the study period were included in the analysis. The minimum mortality temperature was found to be 28.9 °C (82nd percentile). With a subtropical climate, the low temperature has a stronger effect than the high temperature on non-accidental, cardiovascular, respiratory and cancer deaths in Hong Kong. The hot effect was more pronounced in the first few days, while cold effect tended to last up to three weeks. Significant heat effect was only observed in the lower SES groups, whilst the extreme low temperature was associated with significantly higher mortality risk across all SES groups. The older population were susceptible to extreme temperature, especially for cold. (4) Conclusions: This study raised the concern of cold-related health impact in the subtropical region. Compared with high temperature, low temperature may be considered a universal hazard to the entire population in Hong Kong rather than only disproportionally affecting people with lower SES. Future public health policy should reconsider the strategy at both individual and community levels to reduce temperature-related mortality.


Author(s):  
P.P.K. Smith

Grains of pigeonite, a calcium-poor silicate mineral of the pyroxene group, from the Whin Sill dolerite have been ion-thinned and examined by TEM. The pigeonite is strongly zoned chemically from the composition Wo8En64FS28 in the core to Wo13En34FS53 at the rim. Two phase transformations have occurred during the cooling of this pigeonite:- exsolution of augite, a more calcic pyroxene, and inversion of the pigeonite from the high- temperature C face-centred form to the low-temperature primitive form, with the formation of antiphase boundaries (APB's). Different sequences of these exsolution and inversion reactions, together with different nucleation mechanisms of the augite, have created three distinct microstructures depending on the position in the grain.In the core of the grains small platelets of augite about 0.02μm thick have farmed parallel to the (001) plane (Fig. 1). These are thought to have exsolved by homogeneous nucleation. Subsequently the inversion of the pigeonite has led to the creation of APB's.


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