278 research outputs found
Influence motor aktivity on physical development of students
The character of organic carbon (OC) in lake waters is strongly dependent on the time water has spent in the landscape as well as in the lake itself due to continuous biogeochemical OC transformation processes. A common view is that upstream lakes might prolong the water retention in the landscape, resulting in an altered OC character downstream. We calculated the number of lakes upstream for 24,742 Swedish lakes in seven river basins spanning from 56º to 68º N. For each of these lakes, we used a lake volume to discharge comparison on a landscape scale to account for upstream water retention by lakes (Tn tot). We found a surprisingly weak relationship between the number of lakes upstream and Tn tot. Accordingly, we found that the coloured fraction of organic carbon was not related to lake landscape position but significantly related to Tn tot when we analysed lake water chemical data from 1,559 lakes in the studied river basins. Thus, we conclude that water renewal along the aquatic continuum by lateral water inputs offsets cumulative retention by lakes. Based on our findings, we suggest integrating Tn tot in studies that address lake landscape position in the boreal zone to better understand variations in the character of organic carbon across lake districts
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Lake surface temperature [in “State of the Climate in 2017”]
Observed lake surface water temperature anomalies
in 2017 are placed in the context of the recent
warming observed in global surface air temperature
by collating long-term in situ lake
surface temperature observations from some of the
world’s best-studied lakes and a satellite-derived
global lake surface water temperature dataset. The
period 1996–2015, 20 years for which satellite-derived
lake temperatures are available, is used as the base
period for all lake temperature anomaly calculations
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Substantial increase in minimum lake surface temperatures under climate change
The annual minimum of lake surface water temperature influences ecological and biogeochemical processes, but variability and change in this extreme has not been investigated. Here, we analysed observational data from eight European lakes and investigated the changes in annual minimum surface water temperature. We found that, between 1973 and 2014, the annual minimum lake surface temperature has increased at an average rate of +0.35°C decade-1; comparable to the rate of summer average lake surface temperature change during the same period (+0.32°C decade-1). Coherent responses to climatic warming are observed between the increase in annual minimum lake surface temperature and the increase in winter air temperature variations. As a result of the rapid warming of annual minimum lake surface temperatures, some of the studied lakes no longer reach important minimum surface temperature thresholds that occur in winter, with complex and significant potential implications for lakes and the ecosystem services that they provide
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Modulation of Mcl-1 sensitizes glioblastoma to TRAIL-induced apoptosis
Glioblastoma (GBM) is the most aggressive form of primary brain tumour, with dismal patient outcome. Treatment failure is associated with intrinsic or acquired apoptosis resistance and the presence of a highly tumourigenic subpopulation of cancer cells called GBM stem cells. Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) has emerged as a promising novel therapy for some treatment-resistant tumours but unfortunately GBM can be completely resistant to TRAIL monotherapy. In this study, we identified Mcl-1, an anti-apoptotic Bcl-2 family member, as a critical player involved in determining the sensitivity of GBM to TRAIL-induced apoptosis. Effective targeting of Mcl-1 in TRAIL resistant GBM cells, either by gene silencing technology or by treatment with R-roscovitine, a cyclin-dependent kinase inhibitor that targets Mcl-1, was demonstrated to augment sensitivity to TRAIL, both within GBM cells grown as monolayers and in a 3D tumour model. Finally, we highlight that two separate pathways are activated during the apoptotic death of GBM cells treated with a combination of TRAIL and R-roscovitine, one which leads to caspase-8 and caspase-3 activation and a second pathway, involving a Mcl-1:Noxa axis. In conclusion, our study demonstrates that R-roscovitine in combination with TRAIL presents a promising novel strategy to trigger cell death pathways in glioblastoma. Electronic supplementary material The online version of this article (doi:10.1007/s10495-013-0935-2) contains supplementary material, which is available to authorized users
Матеріали міжнародної науково-практичної конференції „Маркетинговий інструментарій управління попитом на товари та послуги“
Матеріали міжнародної науково-практичної конференції є результатом
наукових досліджень авторів з проблем розроблення концептуальних засад
маркетингового інструментарію управління попитом на товари і послуги
України
Increased winter drownings in ice-covered regions with warmer winters
Winter activities on ice are culturally important for many countries, yet they constitute a high
safety risk depending upon the stability of the ice. Because consistently cold periods are
required to form stable and thick ice, warmer winters could degrade ice conditions and
increase the likelihood of falling through the ice. This study provides the first large-scale
assessment of winter drowning from 10 Northern Hemisphere countries. We documented
over 4000 winter drowning events. Winter drownings increased exponentially in regions with
warmer winters when air temperatures neared 0 ̊C. The largest number of drownings
occurred when winter air temperatures were between -5 ̊C and 0 ̊C, when ice is less stable,
and also in regions where indigenous traditions and livelihood require extended time on ice.
Rates of drowning were greatest late in the winter season when ice stability declines. Children and adults up to the age of 39 were at the highest risk of winter drownings. Beyond temperature, differences in cultures, regulations, and human behaviours can be important
additional risk factors. Our findings indicate the potential for increased human mortality with
warmer winter air temperatures. Incorporating drowning prevention plans would improve
adaptation strategies to a changing climate.Funding was provided to SS by the
Ontario Ministry of Research, Innovation and
Science Early Researcher Award and York
University Research Chair programme. Funding
support for BAD was provided by
Kempestiftelserna. AL was supported by Estonian
Research Council Grant PSG 32. The funders had
no role in study design, data collection and analysis, decision to publish, or preparation of the
manuscript.Funding was provided to SS by the
Ontario Ministry of Research, Innovation and
Science Early Researcher Award and York
University Research Chair programme. Funding
support for BAD was provided by
Kempestiftelserna. AL was supported by Estonian
Research Council Grant PSG 32. The funders had
no role in study design, data collection and analysis, decision to publish, or preparation of the
manuscript
NotCal04; comparison/ calibration 14C records 26-50 cal kyr BP
Author Posting. © Arizona Board of Regents on behalf of the University of Arizona, 2004. This article is posted here by permission of Dept. of Geosciences, University of Arizona for personal use, not for redistribution. The definitive version was published in Radiocarbon 46 (2004): 1225-1238.The radiocarbon calibration curve IntCal04 extends back to 26 cal kyr BP. While several high-resolution
records exist beyond this limit, these data sets exhibit discrepancies of up to several millennia. As a result, no calibration curve
for the time range 26–50 cal kyr BP can be recommended as yet, but in this paper the IntCal04 working group compares the
available data sets and offers a discussion of the information that they hold
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