Background Cold stress has negative effects on the growth and health of mammals, and has become a factor restricting livestock development at high latitudes and on plateaus. The gut-liver axis is central to energy met...Background Cold stress has negative effects on the growth and health of mammals, and has become a factor restricting livestock development at high latitudes and on plateaus. The gut-liver axis is central to energy metabolism, and the mechanisms by which it regulates host energy metabolism at cold temperatures have rarely been illustrated. In this study, we evaluated the status of glycolipid metabolism and oxidative stress in pigs based on the gut-liver axis and propose that AMP-activated protein kinase(AMPK) is a key target for alleviating energy stress at cold temperatures by dietary fat supplementation.Results Dietary fat supplementation alleviated the negative effects of cold temperatures on growth performance and digestive enzymes, while hormonal homeostasis was also restored. Moreover, cold temperature exposure increased glucose transport in the jejunum. In contrast, we observed abnormalities in lipid metabolism, which was characterized by the accumulation of bile acids in the ileum and plasma. In addition, the results of the ileal metabolomic analysis were consistent with the energy metabolism measurements in the jejunum, and dietary fat supplementation increased the activity of the mitochondrial respiratory chain and lipid metabolism. As the central nexus of energy metabolism, the state of glycolipid metabolism and oxidative stress in the liver are inconsistent with that in the small intestine. Specifically, we found that cold temperature exposure increased glucose transport in the liver, which fully validates the idea that hormones can act on the liver to regulate glucose output. Additionally, dietary fat supplementation inhibited glucose transport and glycolysis, but increased gluconeogenesis, bile acid cycling, and lipid metabolism. Sustained activation of AMPK, which an energy receptor and regulator, leads to oxidative stress and apoptosis in the liver;dietary fat supplementation alleviates energy stress by reducing AMPK phosphorylation.Conclusions Cold stress reduced the growth performance and aggravated glycolipid metabolism disorders and oxidative stress damage in pigs. Dietary fat supplementation improved growth performance and alleviated cold temperature-induced energy stress through AMPK-mediated mitochondrial homeostasis. In this study, we high-light the importance of AMPK in dietary fat supplementation-mediated alleviation of host energy stress in response to environmental changes.展开更多
Background:In high latitude grassland habitats,altricial nestlings hatching in open-cup nests early in the breeding season must cope with cold temperature challenges.Thyroid hormones(triiodothyronine,T_(3)and thyroxin...Background:In high latitude grassland habitats,altricial nestlings hatching in open-cup nests early in the breeding season must cope with cold temperature challenges.Thyroid hormones(triiodothyronine,T_(3)and thyroxine,T_(4))and corticosterone play a crucial role in avian thermoregulation response to cold.Investigating the endocrine response of altricial nestlings to temperature variation is important for understanding the adaptive mechanisms of individual variation in the timing of breeding in birds.Methods:We compared nest temperature,ambient temperature,body temperature,plasma T_(3),T_(4)and corticosterone levels in Asian Short-toed Lark(Alaudala cheleensis)nestlings hatching in the early-,middle-,and late-stages of the breeding season in Hulunbuir grassland,northeast China.Results:Mean nest temperature in the early-,middle-and late-stage groups was-1.85,3.81 and 10.23℃,respectively,for the 3-day-old nestlings,and 6.83,10.41 and 11.81℃,respectively,for the 6-day-old nestlings.The nest temperature significantly correlated with body temperature,plasma T_(3),T_(4)and corticosterone concentrations of nestlings.Body temperature of 3-day-old nestlings in the early and middle groups was significantly lower than that of the late group,but there was no significant difference between the nestlings in the early and middle groups.The T_(4)and T_(3)concentrations and the ratio of T_(3)/T_(4)of both 3-and 6-day-old nestlings in the early-stage group were significantly higher compared to the middle and late groups.The corticosterone levels of 3-day-old nestlings were significantly higher in the early-stage group compared to the middle-and late-stage groups.Conclusion:Nestlings hatching early responded to cold temperature by increasing thyroid hormones and corticosterone levels even in the early days of post hatching development when the endothermy has not been established.These hormones may play a physiological role in neonatal nestlings coping with cold temperature challenges.展开更多
Germination at low spring temperatures may offer a competitive advantage for the growth and survival of plant species inhabiting temperate forest ecosystems.Pinus koraiensis is a dominant species in temperate forests ...Germination at low spring temperatures may offer a competitive advantage for the growth and survival of plant species inhabiting temperate forest ecosystems.Pinus koraiensis is a dominant species in temperate forests of northeastern China.Its seeds exhibit primary morphophysiological dormancy following dispersal in autumn,limiting natural or artificial regeneration:direct seeding and planting seedlings in spring.The aim of this study was to determine the optimum cold stratification temperature that induces germination to increase towards lower temperatures.Seeds from two populations(Changbaishan and Liangshui)were cold stratified at 0,5 and 10℃.Germination to incubation temperatures(10/5,20/10,25/15 and 30/20℃;14/10 h day/night)were determined after 2 and 4 weeks,and 5.5 and6.5 months of cold stratification.After 5.5 months,approximately 68-91%of seeds from both populations germinated at incubation temperatures of 25/15℃and 30/20℃,regardless of cold stratification temperatures.When the cold stratification temperature was reduced to 0℃and the period increased to 6.5 months,germination at 10/5℃significantly improved,reaching 37%and 64%for the Changbaishan and Liangshui populations,respectively.After 6.5 months of cold stratification,there was a significant linear regression between cold stratification temperatures and germination at10/5℃.The range in temperatures allowing for germination gradually expanded to include lower temperatures with decreasing cold stratification temperatures from 10 to 5℃and further to 0℃.展开更多
Delta carbonate (Delta C, AC) method is a commonly- used surface geochemical exploration method for petroleum surveys. Delta C holds that light hydrocarbon gases leak into near-surface soils or sediments from underl...Delta carbonate (Delta C, AC) method is a commonly- used surface geochemical exploration method for petroleum surveys. Delta C holds that light hydrocarbon gases leak into near-surface soils or sediments from underlying petroleum accumulations, then partly oxidized to CO2, resulting in a special carbonate precipitation, which is termed as Delta carbonate (△C).展开更多
This paper presents new high-resolution proxies and paleoclimatic reconstructions for studying climate changes in China for the past 2000 years. Multi-proxy synthesized reconstructions show that temperature variation ...This paper presents new high-resolution proxies and paleoclimatic reconstructions for studying climate changes in China for the past 2000 years. Multi-proxy synthesized reconstructions show that temperature variation in China has exhibited significant 50–70-yr, 100–120-yr, and 200–250-yr cycles. Results also show that the amplitudes of decadal and centennial temperature variation were 1.3℃ and 0.7℃, respectively, with the latter significantly correlated with long-term changes in solar radiation, especially cold periods, which correspond approximately to sunspot minima. The most rapid warming in China occurred over AD 1870–2000, at a rate of 0.56°± 0.42℃(100 yr)^(-1); however, temperatures recorded in the 20 th century may not be unprecedented for the last 2000 years, as data show records for the periods AD 981–1100 and AD1201–70 are comparable to the present. The ensemble means of dryness/wetness spatial patterns in eastern China across all centennial warm periods illustrate a tripole pattern: dry south of 25°N, wet from 25°–30°N, and dry to the north of 30°N. However, for all centennial cold periods, this spatial pattern also exhibits a meridional distribution. The increase in precipitation over the monsoonal regions of China associated with the 20 th century warming can primarily be attributed to a mega El Nino–Southern Oscillation and the Atlantic Multidecadal Oscillation. In addition, a significant association between increasing numbers of locusts and dry/cold conditions is found in eastern China. Plague intensity also generally increases in concert with wetness in northern China, while more precipitation is likely to have a negative effect in southern China.展开更多
The dynamic changes in the malondialdehyde(MDA), superoxide dismutase(SOD), soluble sugar, proline, and soluble protein contents, as well as the relative electrolyte conductivity and the corresponding cold resista...The dynamic changes in the malondialdehyde(MDA), superoxide dismutase(SOD), soluble sugar, proline, and soluble protein contents, as well as the relative electrolyte conductivity and the corresponding cold resistance, of Cinnamomum bodinieri Level., C. camphora L., and C. caudiferum Kisterm were investigated during the winter months of October 2009 to April 2010. During the short period of temperature decline that lasted until mid-December, the changes in the relative electrolyte conductivity and MDA content with temperature were insignificant. In January, SOD activity continued to increase and then peaked as a result of rapid increases in soluble sugar, proline, soluble protein, as well as the inhibition of the relative electrolyte conductivity and decrease in MDA content. These physiological changes protected the camphor trees from cold damage during winter. From February to March, SOD activity and the soluble protein and proline contents increased with the increase in temperature. However, the relative electrolyte conductivity and MDA content decreased, indicating that the cell membrane damaged by low temperature was gradually being repaired. The cold dip in April led to slight increases in the relative electrolyte conductivity and MDA content. Using a fuzzy mathematics method, the cold resistance adaptability of the camphor trees was divided into three periods namely, the enhancement setting stage, the vigorous stage, and the reducing stage. The cold tolerance abilities were ranked as the following order: C. bodinieri Level〉C. camphora L.〉C. caudiferum Kisterm.展开更多
Developmental disorders(DDs)are a kind of chronic maladies,which can cause serious irreversible detriment to children’s physical and mental health.It is predominantly regulated by the interaction of environment and h...Developmental disorders(DDs)are a kind of chronic maladies,which can cause serious irreversible detriment to children’s physical and mental health.It is predominantly regulated by the interaction of environment and heredity.Cold regions are mainly located in the high latitudes of China.Their living environment is characterized by frequent cold wave,huge temperature difference,severe air pollution,high calorie diet,less exercise,smoking,drinking,etc.In recent years,substantial advances have been made in studies of the correlation between the living environment features in cold regions and the DDs.Accordingly,this article reviews the impact of the peculiar living environment of cold regions on DDs,with a view to provide fresh prevention strategies for reducing the morbidity of DDs in China cold regions by ameliorating living environment.展开更多
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...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℃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℃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.展开更多
Skin sensitive difference of human body sections under clothing is the theoretic foundation of thermal insulation clothing design. By a new method of researching on clothing comfort perception, the skin temperature li...Skin sensitive difference of human body sections under clothing is the theoretic foundation of thermal insulation clothing design. By a new method of researching on clothing comfort perception, the skin temperature live changing procedure of human body sections affected by the same cold stimulation is inspected. Furthermore with the Smirnov test the skin temperatures dynamic changing patterns of main human body sections are obtained.展开更多
`Since the outbreak of COVID-19,various regions have introduced their own TCM prevention and treatment methods.However,there are two opposing views on the nature of cold and temperature.Since modern times,the thought ...`Since the outbreak of COVID-19,various regions have introduced their own TCM prevention and treatment methods.However,there are two opposing views on the nature of cold and temperature.Since modern times,the thought of the unification of cold and temperature has developed rapidly,and many doctors gradually realized the importance and practicability of the unification of cold and temperature,and began to advocate the unification of cold and temperature syndrome.The prevention and treatment of COVID-19 in Jiangxi was developed by Professor Wu Bingcai,a master of Chinese medicine,based on the unified idea of cold and temperature,according to the characteristics of humid climate in Jiangxi,and in combination with the characteristics of COVID-19,the anti-toxin prescription for dispelling cold and desiccating dampness and the anti-toxin prescription for clearing heat and dehumidifying,which achieved exact and satisfactory results in clinical application.展开更多
In order to ensure the safe operation of the compressors used in water chillers,in the present study some interlock protections have been added to the related design.These include a low pressure protection,a high pres...In order to ensure the safe operation of the compressors used in water chillers,in the present study some interlock protections have been added to the related design.These include a low pressure protection,a high pressure protection,an exhaust temperature protection and a differential pressure protection.Some tests have been conducted by tuning the saturation suction and exhaust temperatures of the compressor through adjustment of the cold source outlet temperature and the ambient temperature.The results show that the ambient temperature increases with decreasing device load and increasing fan speed under the same saturated suction temperature;the device refrigerating capacity steps up with augmenting load and dropping saturation exhaust temperature,while it is not greatly affected by the fan speed.Moreover,the Energy efficiency ratio(COP)decreases with the rise of the saturation exhaust temperature.This parameter is not affected much by the device load and fan speed at high saturation exhaust temperature,while it improves on increasing the device load and decreasing the fan speed at low saturation exhaust temperature.展开更多
The low temperature cold damage of paddy rice is the major agricultural meteorological disaster in Ningxia.The real-time monitoring and early warning of low temperature cold damage are very important to develop the ad...The low temperature cold damage of paddy rice is the major agricultural meteorological disaster in Ningxia.The real-time monitoring and early warning of low temperature cold damage are very important to develop the advantages,avoid the disadvantages and reduce the disaster losses.Based on the prior researches on the low temperature cold damage indexes of paddy rice,we improved the small grid reckoning method of temperature and the reckoning precision with the support of GIS.By using the multitemporal remote sensing data,the paddy rice planting zone was picked.The calculation results of low temperature cold damage monitoring indexes were combined with the paddy rice planting zone,which judged the grade distribution and zone of low temperature cold damage in real time.Meanwhile,the low temperature cold damage of paddy rice was done the early warning,and the automatic monitoring early warning system was developed by using the weather forecast data.This method and system were applied to the business works,and the monitoring and early warning products of paddy rice low temperature cold damage business were made.The monitoring results basically corresponded with the actual situation,and the better monitoring service effect was gained.展开更多
This paper investigates the impact of cold and snow on daily and hourly truck traffic volume on a primary highway in Alberta, Canada. This research is based on a detailed case study of 5 years of weigh-in-motion data ...This paper investigates the impact of cold and snow on daily and hourly truck traffic volume on a primary highway in Alberta, Canada. This research is based on a detailed case study of 5 years of weigh-in-motion data recorded continuously at Leduc site on Highway 2A. Influence of the winter conditions on truck type distribution is examined by classifying trucks into single-unit trucks, single-trailer, and multi-trailer units. It is evident from the study that proportion of the three truck classes in the total truck traffic remained essentially stable over the study period (2005-2009). Dummy-variable regression models are used to relate daily and hourly truck traffic volume with snowfall and categorized cold as independent variables. The statistical significance of all the independent variables used in the model is established by conducting tests such as R2, F test, incremental F test, and t test. The study results suggested that the truck volume is not significantly affected by the normal snowfall or the typical cold temperatures, i.e., average daily snowfall about less than 15 cm or temperatures higher than -25 ℃ are not likely to affect the truck traffic patterns. It is believed that the findings of this study can benefit highway agencies in developing programs and policies for efficient monitoring of truck traffic throughout the year and snow removal during the winter season in Canada.展开更多
In order to improve the operational application ability of the Fengyun-4A(FY-4A)new sounding dataset,in this paper,validation of the FY-4A Geosynchronous Interferometric Infrared Sounder(FY-4A/GIIRS)temperature was ca...In order to improve the operational application ability of the Fengyun-4A(FY-4A)new sounding dataset,in this paper,validation of the FY-4A Geosynchronous Interferometric Infrared Sounder(FY-4A/GIIRS)temperature was carried out using the balloon sounding temperature from meteorological sounding stations.More than 350,000 samples were obtained through time–space matching,and the results show that the FY-4A/GIIRS temperature mean bias(MB)is 0.07°C,the mean absolute error(MAE)is 1.80°C,the root-mean-square error(RMSE)is 2.546°C,and the correlation coefficient(RR)is 0.95.The FY-4A/GIIRS temperature error is relatively larger in the upper and lower troposphere,and relatively smaller in the middle troposphere;that is,the temperature at 500 hPa is better than that at 850 hPa.The temporal variation is smaller in the upper and middle troposphere than in the lower troposphere.The reconstruction of missing data of FY-4A/GIIRS temperature in cloudy areas is also carried out and the results are evaluated.The spatial distribution of reconstructed FY-4A/GIIRS temperature and the fifth generation ECMWF reanalysis(ERA5)data is consistent and completely retains the minimum temperature center with high precision of FY-4A/GIIRS.There are more detailed characteristics of intensity and position at the cold center than that of the reanalysis data.Therefore,an operational satellite retrieval temperature product with time–space continuity and high accuracy is formed.The reconstructed FY-4A/GIIRS temperature is used to monitor a strong cold wave event in November 2021.The results show that the product effectively monitors the movement and intensity of cold air activities,and it also has good indication for the phase transition of rain and snow triggered by cold wave.展开更多
Cold plasma at room temperature and pressure is an emerging and novel tool for the inactivation of cell derived from its ionic energy,which is capable of breaking bonds such as carbon-carbon,carbon-hydrogen,carbon-oxy...Cold plasma at room temperature and pressure is an emerging and novel tool for the inactivation of cell derived from its ionic energy,which is capable of breaking bonds such as carbon-carbon,carbon-hydrogen,carbon-oxygen,among others,these being the ones that support the biological structure of microorganisms.This work tries to create its own infrastructure that includes a high voltage source,an infrared trigger which reduces the effect of the ozone created,an ionic reactor in which the plasma acts at atmospheric temperature and pressure,and a magnetic field that allow aligning the plasma to the combined processes that are carried out.展开更多
Plant long noncoding RNAs(lncRNAs)have emerged as important regulators of chromatin dynamics,impacting on transcriptional programs leading to different developmental outputs.The lncRNA AUXIN-REGULATED PROMOTER LOOP(AP...Plant long noncoding RNAs(lncRNAs)have emerged as important regulators of chromatin dynamics,impacting on transcriptional programs leading to different developmental outputs.The lncRNA AUXIN-REGULATED PROMOTER LOOP(APOLO)directly recognizes multiple independent loci across the Arabidopsis genome and modulates their three-dimensional chromatin conformation,leading to transcriptional shifts.Here,we show that APOLO recognizes the locus encoding the root hair(RH)master regulator ROOT HAIR DEFECTIVE 6(RHD6)and controls RHD6 transcriptional activity,leading to cold-enhanced RH elongation through the consequent activation of the transcription factor gene RHD6-like RSL4.Furthermore,we demonstrate that APOLO interacts with the transcription factor WRKY42 and modulates its binding to the RHD6 promoter.WRKY42 is required for the activation of RHD6 by low temperatures and WRKY42 deregulation impairs cold-induced RH expansion.Collectively,our results indicate that a novel ribonucleoprotein complex with APOLO and WRKY42 forms a regulatory hub to activate RHD6 by shaping its epigenetic environment and integrate signals governing RH growth and development.展开更多
Cold air outbreaks(CAOs)always hit East Asia during boreal winter and have significant impacts on human health and public transport.The amplitude and route of CAOs are closely associated with blocking circulations o...Cold air outbreaks(CAOs)always hit East Asia during boreal winter and have significant impacts on human health and public transport.The amplitude and route of CAOs are closely associated with blocking circulations over the Eurasian continent.Two categories of CAOs are recognized,namely,the ordinary cold wave events(CWEs)and the extensive and persistent extreme cold events(EPECEs),with the latter having even stronger impacts.The blocking features associated with these two types of CAOs and their differences are investigated in this study on the intraseasonal timescale.What these two CAOs do have in common is that they are both preceded by the intensification and recurrence of a blocking high over the midlatitude North Atlantic.The difference between these events is primarily reflected on the spatial scale and duration of the corresponding blocking high.During the CWEs,blocking occurs around the Ural Mountains,and exhibits a regional feature.The resulting cold air temperature persists for only up to 8 days.In contrast,during the EPECEs,the blocking region is quite extensive and is not only confined around the Ural Mountains but also extends eastward into Northeast Asia in a southwest–northeast orientation.As a result,the cold air tends to accumulate over a large area and persists for a much longer time.The blocking activity is primarily induced by an increased frequency and eastward extension of the synoptic anticyclonic Rossby wave breaking(AWB).Compared with the CWEs,characterized by a regional and short-lived synoptic AWB frequency,the EPE-CEs tend to be accompanied by more recurrent and eastward extensions of the synoptic AWB.展开更多
At the 2022 Winter Olympics in Beijing,the XC skiing,biathlon and nordic combined events will be held at altitudes of~1700 m above sea level,possibly in cold environmental conditions and while requiring adjustment to ...At the 2022 Winter Olympics in Beijing,the XC skiing,biathlon and nordic combined events will be held at altitudes of~1700 m above sea level,possibly in cold environmental conditions and while requiring adjustment to several time zones.However,the ongoing COVID-19 pandemic may lead to sub-optimal preparations.The current commentary provides the following evidence-based recommendations for the Olympic preparations:make sure to have extensive experience of training(>60 days annually)and competition at or above the altitude of competition(~1700 m),to optimize and individualize your strategies for acclimatization and competition.In preparing for the Olympics,10-14 days at~1700 m seems to optimize performance at this altitude effectively.An alternative strategy involves two-three weeks of training at>2000 m,followed by 7-10 days of tapering off at~1700 m.During each of the last 3 or 4 days prior to departure,shift your sleeping and eating schedule by 0.5-1 h towards the time zone in Beijing.In addition,we recommend that you arrive in Beijing one day earlier for each hour change in time zone,followed by appropriate timing of exposure to daylight,meals,social contacts,and naps,in combination with a gradual increase in training load.Optimize your own individual procedures for warming-up,as well as for maintaining body temperature during the period between the warm-up and competition,effective treatment of asthma(if necessary)and pacing at~1700 m with cold ambient temperatures.Although we hope that these recommendations will be helpful in preparing for the Beijing Olympics in 2022,there is a clear need for more solid evidence gained through new sophisticated experiments and observational studies.展开更多
基金funded by the National Key Research and Development Program of China (2021YFD1300403)。
文摘Background Cold stress has negative effects on the growth and health of mammals, and has become a factor restricting livestock development at high latitudes and on plateaus. The gut-liver axis is central to energy metabolism, and the mechanisms by which it regulates host energy metabolism at cold temperatures have rarely been illustrated. In this study, we evaluated the status of glycolipid metabolism and oxidative stress in pigs based on the gut-liver axis and propose that AMP-activated protein kinase(AMPK) is a key target for alleviating energy stress at cold temperatures by dietary fat supplementation.Results Dietary fat supplementation alleviated the negative effects of cold temperatures on growth performance and digestive enzymes, while hormonal homeostasis was also restored. Moreover, cold temperature exposure increased glucose transport in the jejunum. In contrast, we observed abnormalities in lipid metabolism, which was characterized by the accumulation of bile acids in the ileum and plasma. In addition, the results of the ileal metabolomic analysis were consistent with the energy metabolism measurements in the jejunum, and dietary fat supplementation increased the activity of the mitochondrial respiratory chain and lipid metabolism. As the central nexus of energy metabolism, the state of glycolipid metabolism and oxidative stress in the liver are inconsistent with that in the small intestine. Specifically, we found that cold temperature exposure increased glucose transport in the liver, which fully validates the idea that hormones can act on the liver to regulate glucose output. Additionally, dietary fat supplementation inhibited glucose transport and glycolysis, but increased gluconeogenesis, bile acid cycling, and lipid metabolism. Sustained activation of AMPK, which an energy receptor and regulator, leads to oxidative stress and apoptosis in the liver;dietary fat supplementation alleviates energy stress by reducing AMPK phosphorylation.Conclusions Cold stress reduced the growth performance and aggravated glycolipid metabolism disorders and oxidative stress damage in pigs. Dietary fat supplementation improved growth performance and alleviated cold temperature-induced energy stress through AMPK-mediated mitochondrial homeostasis. In this study, we high-light the importance of AMPK in dietary fat supplementation-mediated alleviation of host energy stress in response to environmental changes.
基金supported by the National Natural Science Foundation of China(No.32071515)。
文摘Background:In high latitude grassland habitats,altricial nestlings hatching in open-cup nests early in the breeding season must cope with cold temperature challenges.Thyroid hormones(triiodothyronine,T_(3)and thyroxine,T_(4))and corticosterone play a crucial role in avian thermoregulation response to cold.Investigating the endocrine response of altricial nestlings to temperature variation is important for understanding the adaptive mechanisms of individual variation in the timing of breeding in birds.Methods:We compared nest temperature,ambient temperature,body temperature,plasma T_(3),T_(4)and corticosterone levels in Asian Short-toed Lark(Alaudala cheleensis)nestlings hatching in the early-,middle-,and late-stages of the breeding season in Hulunbuir grassland,northeast China.Results:Mean nest temperature in the early-,middle-and late-stage groups was-1.85,3.81 and 10.23℃,respectively,for the 3-day-old nestlings,and 6.83,10.41 and 11.81℃,respectively,for the 6-day-old nestlings.The nest temperature significantly correlated with body temperature,plasma T_(3),T_(4)and corticosterone concentrations of nestlings.Body temperature of 3-day-old nestlings in the early and middle groups was significantly lower than that of the late group,but there was no significant difference between the nestlings in the early and middle groups.The T_(4)and T_(3)concentrations and the ratio of T_(3)/T_(4)of both 3-and 6-day-old nestlings in the early-stage group were significantly higher compared to the middle and late groups.The corticosterone levels of 3-day-old nestlings were significantly higher in the early-stage group compared to the middle-and late-stage groups.Conclusion:Nestlings hatching early responded to cold temperature by increasing thyroid hormones and corticosterone levels even in the early days of post hatching development when the endothermy has not been established.These hormones may play a physiological role in neonatal nestlings coping with cold temperature challenges.
基金the National Natural Science Foundation of China(No.31901300)Natural Science Foundation of Guizhou Province+2 种基金China(No.(2019)1165)Science and Technology Foundation of Guizhou ProvinceChina(No.[2018]137,No.[2018]133)。
文摘Germination at low spring temperatures may offer a competitive advantage for the growth and survival of plant species inhabiting temperate forest ecosystems.Pinus koraiensis is a dominant species in temperate forests of northeastern China.Its seeds exhibit primary morphophysiological dormancy following dispersal in autumn,limiting natural or artificial regeneration:direct seeding and planting seedlings in spring.The aim of this study was to determine the optimum cold stratification temperature that induces germination to increase towards lower temperatures.Seeds from two populations(Changbaishan and Liangshui)were cold stratified at 0,5 and 10℃.Germination to incubation temperatures(10/5,20/10,25/15 and 30/20℃;14/10 h day/night)were determined after 2 and 4 weeks,and 5.5 and6.5 months of cold stratification.After 5.5 months,approximately 68-91%of seeds from both populations germinated at incubation temperatures of 25/15℃and 30/20℃,regardless of cold stratification temperatures.When the cold stratification temperature was reduced to 0℃and the period increased to 6.5 months,germination at 10/5℃significantly improved,reaching 37%and 64%for the Changbaishan and Liangshui populations,respectively.After 6.5 months of cold stratification,there was a significant linear regression between cold stratification temperatures and germination at10/5℃.The range in temperatures allowing for germination gradually expanded to include lower temperatures with decreasing cold stratification temperatures from 10 to 5℃and further to 0℃.
基金supported by National Natural Science Foundation of China(grant No.41302099)Open Foundation of State Key Laboratory of Organic Geochemistry(grant No.OG2015-03)Open Foundation of Key Laboratory of Marine Mineral Resources,Ministry of Land and Resources(grant No.KLMMR-2013-A-25)
文摘Delta carbonate (Delta C, AC) method is a commonly- used surface geochemical exploration method for petroleum surveys. Delta C holds that light hydrocarbon gases leak into near-surface soils or sediments from underlying petroleum accumulations, then partly oxidized to CO2, resulting in a special carbonate precipitation, which is termed as Delta carbonate (△C).
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA050800)the Key Program of the Chinese Academy of Sciences (Grant No. KJZD-EW-TZ-G10)the National Natural Science Foundation of China (Grant No.41671201 and 91525101)
文摘This paper presents new high-resolution proxies and paleoclimatic reconstructions for studying climate changes in China for the past 2000 years. Multi-proxy synthesized reconstructions show that temperature variation in China has exhibited significant 50–70-yr, 100–120-yr, and 200–250-yr cycles. Results also show that the amplitudes of decadal and centennial temperature variation were 1.3℃ and 0.7℃, respectively, with the latter significantly correlated with long-term changes in solar radiation, especially cold periods, which correspond approximately to sunspot minima. The most rapid warming in China occurred over AD 1870–2000, at a rate of 0.56°± 0.42℃(100 yr)^(-1); however, temperatures recorded in the 20 th century may not be unprecedented for the last 2000 years, as data show records for the periods AD 981–1100 and AD1201–70 are comparable to the present. The ensemble means of dryness/wetness spatial patterns in eastern China across all centennial warm periods illustrate a tripole pattern: dry south of 25°N, wet from 25°–30°N, and dry to the north of 30°N. However, for all centennial cold periods, this spatial pattern also exhibits a meridional distribution. The increase in precipitation over the monsoonal regions of China associated with the 20 th century warming can primarily be attributed to a mega El Nino–Southern Oscillation and the Atlantic Multidecadal Oscillation. In addition, a significant association between increasing numbers of locusts and dry/cold conditions is found in eastern China. Plague intensity also generally increases in concert with wetness in northern China, while more precipitation is likely to have a negative effect in southern China.
基金Supported by Youth Science Foundation from Henan University of Science and Technology(2013)
文摘The dynamic changes in the malondialdehyde(MDA), superoxide dismutase(SOD), soluble sugar, proline, and soluble protein contents, as well as the relative electrolyte conductivity and the corresponding cold resistance, of Cinnamomum bodinieri Level., C. camphora L., and C. caudiferum Kisterm were investigated during the winter months of October 2009 to April 2010. During the short period of temperature decline that lasted until mid-December, the changes in the relative electrolyte conductivity and MDA content with temperature were insignificant. In January, SOD activity continued to increase and then peaked as a result of rapid increases in soluble sugar, proline, soluble protein, as well as the inhibition of the relative electrolyte conductivity and decrease in MDA content. These physiological changes protected the camphor trees from cold damage during winter. From February to March, SOD activity and the soluble protein and proline contents increased with the increase in temperature. However, the relative electrolyte conductivity and MDA content decreased, indicating that the cell membrane damaged by low temperature was gradually being repaired. The cold dip in April led to slight increases in the relative electrolyte conductivity and MDA content. Using a fuzzy mathematics method, the cold resistance adaptability of the camphor trees was divided into three periods namely, the enhancement setting stage, the vigorous stage, and the reducing stage. The cold tolerance abilities were ranked as the following order: C. bodinieri Level〉C. camphora L.〉C. caudiferum Kisterm.
基金This work was supported by the Key Project of Harbin Medical University Cultivation Fund.
文摘Developmental disorders(DDs)are a kind of chronic maladies,which can cause serious irreversible detriment to children’s physical and mental health.It is predominantly regulated by the interaction of environment and heredity.Cold regions are mainly located in the high latitudes of China.Their living environment is characterized by frequent cold wave,huge temperature difference,severe air pollution,high calorie diet,less exercise,smoking,drinking,etc.In recent years,substantial advances have been made in studies of the correlation between the living environment features in cold regions and the DDs.Accordingly,this article reviews the impact of the peculiar living environment of cold regions on DDs,with a view to provide fresh prevention strategies for reducing the morbidity of DDs in China cold regions by ameliorating living environment.
基金Supported by Municipal Science and Technology Cooperation Project of Guizhou Province(52020-2015-01-02)Science and Technology Plan Project of Guizhou Province(QINKEHE NY[2012]3020)Liupanshui Planning Project(52020-2021-01-03).
文摘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℃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℃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.
基金Supported by the national education ministry key research project 02107
文摘Skin sensitive difference of human body sections under clothing is the theoretic foundation of thermal insulation clothing design. By a new method of researching on clothing comfort perception, the skin temperature live changing procedure of human body sections affected by the same cold stimulation is inspected. Furthermore with the Smirnov test the skin temperatures dynamic changing patterns of main human body sections are obtained.
基金Science and Technology Research Project of Jiangxi Provincial Department of Science and Technology(No.S2020ZPYFG0006)"National Innovative Backbone Talents of Traditional Chinese Medicine"Training Program(National Letter of Education of Traditional Chinese Medicine Personnel[2019]No.128)
文摘`Since the outbreak of COVID-19,various regions have introduced their own TCM prevention and treatment methods.However,there are two opposing views on the nature of cold and temperature.Since modern times,the thought of the unification of cold and temperature has developed rapidly,and many doctors gradually realized the importance and practicability of the unification of cold and temperature,and began to advocate the unification of cold and temperature syndrome.The prevention and treatment of COVID-19 in Jiangxi was developed by Professor Wu Bingcai,a master of Chinese medicine,based on the unified idea of cold and temperature,according to the characteristics of humid climate in Jiangxi,and in combination with the characteristics of COVID-19,the anti-toxin prescription for dispelling cold and desiccating dampness and the anti-toxin prescription for clearing heat and dehumidifying,which achieved exact and satisfactory results in clinical application.
基金This work was supported by the National Natural Science Foundation of China(No.41877251)Major Science and Technology Projects of Xinxiang City(No.21ZD012).
文摘In order to ensure the safe operation of the compressors used in water chillers,in the present study some interlock protections have been added to the related design.These include a low pressure protection,a high pressure protection,an exhaust temperature protection and a differential pressure protection.Some tests have been conducted by tuning the saturation suction and exhaust temperatures of the compressor through adjustment of the cold source outlet temperature and the ambient temperature.The results show that the ambient temperature increases with decreasing device load and increasing fan speed under the same saturated suction temperature;the device refrigerating capacity steps up with augmenting load and dropping saturation exhaust temperature,while it is not greatly affected by the fan speed.Moreover,the Energy efficiency ratio(COP)decreases with the rise of the saturation exhaust temperature.This parameter is not affected much by the device load and fan speed at high saturation exhaust temperature,while it improves on increasing the device load and decreasing the fan speed at low saturation exhaust temperature.
基金Supported by The New Technology Popularization Item of China Meteorological Administration(CMATG005M44)~~
文摘The low temperature cold damage of paddy rice is the major agricultural meteorological disaster in Ningxia.The real-time monitoring and early warning of low temperature cold damage are very important to develop the advantages,avoid the disadvantages and reduce the disaster losses.Based on the prior researches on the low temperature cold damage indexes of paddy rice,we improved the small grid reckoning method of temperature and the reckoning precision with the support of GIS.By using the multitemporal remote sensing data,the paddy rice planting zone was picked.The calculation results of low temperature cold damage monitoring indexes were combined with the paddy rice planting zone,which judged the grade distribution and zone of low temperature cold damage in real time.Meanwhile,the low temperature cold damage of paddy rice was done the early warning,and the automatic monitoring early warning system was developed by using the weather forecast data.This method and system were applied to the business works,and the monitoring and early warning products of paddy rice low temperature cold damage business were made.The monitoring results basically corresponded with the actual situation,and the better monitoring service effect was gained.
基金the Natural Science and Engineering Research Council of Canada(NSERC)the Faculty of Graduate Studies at the University of Regina,and Saskatchewan Government Insurance(SGI)for their financial support
文摘This paper investigates the impact of cold and snow on daily and hourly truck traffic volume on a primary highway in Alberta, Canada. This research is based on a detailed case study of 5 years of weigh-in-motion data recorded continuously at Leduc site on Highway 2A. Influence of the winter conditions on truck type distribution is examined by classifying trucks into single-unit trucks, single-trailer, and multi-trailer units. It is evident from the study that proportion of the three truck classes in the total truck traffic remained essentially stable over the study period (2005-2009). Dummy-variable regression models are used to relate daily and hourly truck traffic volume with snowfall and categorized cold as independent variables. The statistical significance of all the independent variables used in the model is established by conducting tests such as R2, F test, incremental F test, and t test. The study results suggested that the truck volume is not significantly affected by the normal snowfall or the typical cold temperatures, i.e., average daily snowfall about less than 15 cm or temperatures higher than -25 ℃ are not likely to affect the truck traffic patterns. It is believed that the findings of this study can benefit highway agencies in developing programs and policies for efficient monitoring of truck traffic throughout the year and snow removal during the winter season in Canada.
基金Supported by the National Natural Science Foundation of China(42175014)National Key Research and Development Program of China(2021YFB3900400).
文摘In order to improve the operational application ability of the Fengyun-4A(FY-4A)new sounding dataset,in this paper,validation of the FY-4A Geosynchronous Interferometric Infrared Sounder(FY-4A/GIIRS)temperature was carried out using the balloon sounding temperature from meteorological sounding stations.More than 350,000 samples were obtained through time–space matching,and the results show that the FY-4A/GIIRS temperature mean bias(MB)is 0.07°C,the mean absolute error(MAE)is 1.80°C,the root-mean-square error(RMSE)is 2.546°C,and the correlation coefficient(RR)is 0.95.The FY-4A/GIIRS temperature error is relatively larger in the upper and lower troposphere,and relatively smaller in the middle troposphere;that is,the temperature at 500 hPa is better than that at 850 hPa.The temporal variation is smaller in the upper and middle troposphere than in the lower troposphere.The reconstruction of missing data of FY-4A/GIIRS temperature in cloudy areas is also carried out and the results are evaluated.The spatial distribution of reconstructed FY-4A/GIIRS temperature and the fifth generation ECMWF reanalysis(ERA5)data is consistent and completely retains the minimum temperature center with high precision of FY-4A/GIIRS.There are more detailed characteristics of intensity and position at the cold center than that of the reanalysis data.Therefore,an operational satellite retrieval temperature product with time–space continuity and high accuracy is formed.The reconstructed FY-4A/GIIRS temperature is used to monitor a strong cold wave event in November 2021.The results show that the product effectively monitors the movement and intensity of cold air activities,and it also has good indication for the phase transition of rain and snow triggered by cold wave.
文摘Cold plasma at room temperature and pressure is an emerging and novel tool for the inactivation of cell derived from its ionic energy,which is capable of breaking bonds such as carbon-carbon,carbon-hydrogen,carbon-oxygen,among others,these being the ones that support the biological structure of microorganisms.This work tries to create its own infrastructure that includes a high voltage source,an infrared trigger which reduces the effect of the ozone created,an ionic reactor in which the plasma acts at atmospheric temperature and pressure,and a magnetic field that allow aligning the plasma to the combined processes that are carried out.
基金supported by grants from ANPCyT(PICT2016-0132 and PICT2017-0066)Instituto Milenio iBio-Iniciativa Cientffica Milenio,MINECON to J.M.E.
文摘Plant long noncoding RNAs(lncRNAs)have emerged as important regulators of chromatin dynamics,impacting on transcriptional programs leading to different developmental outputs.The lncRNA AUXIN-REGULATED PROMOTER LOOP(APOLO)directly recognizes multiple independent loci across the Arabidopsis genome and modulates their three-dimensional chromatin conformation,leading to transcriptional shifts.Here,we show that APOLO recognizes the locus encoding the root hair(RH)master regulator ROOT HAIR DEFECTIVE 6(RHD6)and controls RHD6 transcriptional activity,leading to cold-enhanced RH elongation through the consequent activation of the transcription factor gene RHD6-like RSL4.Furthermore,we demonstrate that APOLO interacts with the transcription factor WRKY42 and modulates its binding to the RHD6 promoter.WRKY42 is required for the activation of RHD6 by low temperatures and WRKY42 deregulation impairs cold-induced RH expansion.Collectively,our results indicate that a novel ribonucleoprotein complex with APOLO and WRKY42 forms a regulatory hub to activate RHD6 by shaping its epigenetic environment and integrate signals governing RH growth and development.
基金Supported by the National Natural Science Foundation of China(41305047,41375064,and 41630424)National Science and Technology Support Program of China(2015BAC03B03)
文摘Cold air outbreaks(CAOs)always hit East Asia during boreal winter and have significant impacts on human health and public transport.The amplitude and route of CAOs are closely associated with blocking circulations over the Eurasian continent.Two categories of CAOs are recognized,namely,the ordinary cold wave events(CWEs)and the extensive and persistent extreme cold events(EPECEs),with the latter having even stronger impacts.The blocking features associated with these two types of CAOs and their differences are investigated in this study on the intraseasonal timescale.What these two CAOs do have in common is that they are both preceded by the intensification and recurrence of a blocking high over the midlatitude North Atlantic.The difference between these events is primarily reflected on the spatial scale and duration of the corresponding blocking high.During the CWEs,blocking occurs around the Ural Mountains,and exhibits a regional feature.The resulting cold air temperature persists for only up to 8 days.In contrast,during the EPECEs,the blocking region is quite extensive and is not only confined around the Ural Mountains but also extends eastward into Northeast Asia in a southwest–northeast orientation.As a result,the cold air tends to accumulate over a large area and persists for a much longer time.The blocking activity is primarily induced by an increased frequency and eastward extension of the synoptic anticyclonic Rossby wave breaking(AWB).Compared with the CWEs,characterized by a regional and short-lived synoptic AWB frequency,the EPE-CEs tend to be accompanied by more recurrent and eastward extensions of the synoptic AWB.
文摘At the 2022 Winter Olympics in Beijing,the XC skiing,biathlon and nordic combined events will be held at altitudes of~1700 m above sea level,possibly in cold environmental conditions and while requiring adjustment to several time zones.However,the ongoing COVID-19 pandemic may lead to sub-optimal preparations.The current commentary provides the following evidence-based recommendations for the Olympic preparations:make sure to have extensive experience of training(>60 days annually)and competition at or above the altitude of competition(~1700 m),to optimize and individualize your strategies for acclimatization and competition.In preparing for the Olympics,10-14 days at~1700 m seems to optimize performance at this altitude effectively.An alternative strategy involves two-three weeks of training at>2000 m,followed by 7-10 days of tapering off at~1700 m.During each of the last 3 or 4 days prior to departure,shift your sleeping and eating schedule by 0.5-1 h towards the time zone in Beijing.In addition,we recommend that you arrive in Beijing one day earlier for each hour change in time zone,followed by appropriate timing of exposure to daylight,meals,social contacts,and naps,in combination with a gradual increase in training load.Optimize your own individual procedures for warming-up,as well as for maintaining body temperature during the period between the warm-up and competition,effective treatment of asthma(if necessary)and pacing at~1700 m with cold ambient temperatures.Although we hope that these recommendations will be helpful in preparing for the Beijing Olympics in 2022,there is a clear need for more solid evidence gained through new sophisticated experiments and observational studies.