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Climate change impacts on the regional hydrological cycle are compared for model projections following an ambitious emissions-reduction scenario (E1) and a medium-high emissions scenario with no mitigation policy (A1B). The E1 scenario is designed to limit global annual mean warming to 2 °C or less above pre-industrial levels. A multi-model ensemble consisting of ten coupled atmosphere-ocean general circulation models is analyzed, which includes five Earth System Models containing interactive carbon cycles. The aim of the study is to assess the changes that could be mitigated under the E1 scenario and to identify regions where even small climate change may lead to strong changes in precipitation, cloud cover and evapotranspiration. In these regions the hydrological cycle is considered particularly vulnerable to climate change, highlighting the need for adaptation measures even if strong mitigation of climate change would be achieved. In the A1B projections, there are significant drying trends in sub-tropical regions, precipitation increases in high latitudes and some monsoon regions, as well as changes in cloudiness and evapotranspiration. These signals are reduced in E1 scenario projections. However, even under the E1 scenario, significant precipitation decrease in the subtropics and increase in high latitudes are projected. Particularly the Amazon region shows strong drying tendencies in some models, most probably related to vegetation interaction. Where climate change is relatively small, the E1 scenario tends to keep the average magnitude of potential changes at a level comparable to current intra-seasonal to inter-annual variability at that location. Such regions are mainly located in the mid-latitudes. [ABSTRACT FROM AUTHOR]

Perennial grass systems are being evaluated as a bioenergy feedstock in the northern Great Plains. Inter-annual and inter-seasonal precipitation variation in this region will require efficient water use to maintain sufficient yield production to support a mature bioenergy industry. Objectives were to evaluate the impact of a May-June (early season) and a July-August (late season) drought on the water use efficiency (WUE), amount of water used, and biomass production in monocultures of switchgrass ( Panicum virgatum L.), western wheatgrass ( Pascopyrum smithii (Rydb.) Á. Löve), and a western wheatgrass-alfalfa ( Medicago sativa L.) mixture using an automated rainout shelter. WUE was strongly driven by biomass accumulation and ranged from 5.6 to 7.4 g biomass mm water for switchgrass to 1.06 to 2.07 g biomass mm water used with western wheatgrass. Timing of water stress affected WUE more in western wheatgrass and the western wheatgrass-alfalfa mixture than switchgrass. Water deficit for the western wheatgrass-alfalfa mixture was 23 % lower than western wheatgrass ( P = 0.0045) and 31 % lower than switchgrass ( P < 0.0001) under the May-June stress water treatment, while switchgrass had a 37 and 38 % greater water deficit than did western wheatgrass or western wheatgrass-alfalfa mixture, respectively ( P < 0.001) under the July-August water stress treatment. Water depletion was always greatest in the upper 30 cm. Switchgrass had greater WUE but resulted in greater soil water depletion at the end of the growing season compared to western wheatgrass and a western wheatgrass-alfalfa mixture which may be a concern under multi-year drought conditions. [ABSTRACT FROM AUTHOR]

With an increasing political focus on limiting global warming to less than 2 °C above pre-industrial levels it is vital to understand the consequences of these targets on key parts of the climate system. Here, we focus on changes in sea level and sea ice, comparing twenty-first century projections with increased greenhouse gas concentrations (using the mid-range IPCC A1B emissions scenario) with those under a mitigation scenario with large reductions in emissions (the E1 scenario). At the end of the twenty-first century, the global mean steric sea level rise is reduced by about a third in the mitigation scenario compared with the A1B scenario. Changes in surface air temperature are found to be poorly correlated with steric sea level changes. While the projected decreases in sea ice extent during the first half of the twenty-first century are independent of the season or scenario, especially in the Arctic, the seasonal cycle of sea ice extent is amplified. By the end of the century the Arctic becomes sea ice free in September in the A1B scenario in most models. In the mitigation scenario the ice does not disappear in the majority of models, but is reduced by 42 % of the present September extent. Results for Antarctic sea ice changes reveal large initial biases in the models and a significant correlation between projected changes and the initial extent. This latter result highlights the necessity for further refinements in Antarctic sea ice modelling for more reliable projections of future sea ice. [ABSTRACT FROM AUTHOR]

The global three-dimensional Lagrangian chemistry-transport model STOCHEM has been used to follow changes in the tropospheric distributions of methane CH4 andozone O3 following the emission of pulses of the oxides of nitrogen NOx. Month-long emission pulses of NOx produce deficits in CH4 mixing ratios that bring about negative radiative forcing (climate cooling) and decay away with e-folding times of 10-15 years. They also produce short-term excesses in O3 mixing ratios that bring about positive radiative forcing (climate warming) that decay over several months to produce deficits, with their attendant negative radiative forcing (climate cooling) that decays away in step with the CH4 deficits. Total time-integrated net radiative forcing is markedly influenced by cancellation between the negative CH4 and long-term O3 contributions and the positive short-term O3 contribution to leave a small negative residual. Consequently, total net radiative forcing from NOx emission pulses and the global warming potentials derived from them, show a strong dependence on the magnitudes, locations and seasons of the emissions. These dependences are illustrated using the Asian continent as an example and demonstrate that there is no simple robust relationship between continental-scale NOx emissions and globally-integrated radiative forcing. We find that the magnitude of the time-integrated radiative forcing from NOx-driven CH4 depletion tends to approach and outweigh that from ozone enhancement, leaving net time-integrated radiative forcings and global warming potentials negative (climate cooling) in contrast to the situation for aircraft NOx (climate warming). Control of man-made surface NOx emissions alone may lead to positive radiative forcing (climate warming). [ABSTRACT FROM AUTHOR]

L1 cell adhesion molecule (L1-CAM) is a transmembrane cell adhesion molecule involved in cell migration and axon guidance in the developing nervous system. L1 is also overexpressed in ovarian and endometrial carcinomas and is associated with a bad prognosis. In carcinoma cell lines, L1 overexpression augments cell motility, tumor growth in mice and induces expression of Erk-dependent genes. Here, we show that a mutation in the cytoplasmic portion of L1 (T1247A, S1248A) abrogates Erk activation, blocks cell migration on extracellular matrix proteins and did not augment tumor growth in non-obese diabetic/severe combined immuno-deficient mice. In cells expressing mutant L1, the induction of Erk-dependent genes such as β3-integrin, cathepsin-B and several transcription factors is eliminated and the invasive phenotype is abrogated. L1 antibodies showed similar effects. They prevented Erk activation and interfered with the Erk-dependent gene expression pattern. These findings provide a rationale for the mode of action of L1 antibodies and suggest that interference with L1 function could become a valuable target for therapy.Oncogene (2008) 27, 1281–1289; doi:10.1038/sj.onc.1210747; published online 22 October 2007 [ABSTRACT FROM AUTHOR]

To assess the sensitivity of direct plating of bovine fecal samples for detection of Escherichia coli O157:H7, calves ( n = 28) were orally inoculated with 109 colony-forming units (cfu) per calf of a mixture of three strains of nalidixic acid-resistant E. coli O157:H7, and fecal samples were collected for analysis. One-gram samples from inoculated calves were mixed with 9 mL of Gram-negative broth with vancomycin, cefixime, and cefsoludin. From this suspension, serial dilutions were made (10−1 to 10−4) and spread plated in triplicate on Sorbitol MacConkey agar with nalidixic acid for enumeration of E. coli O157:H7 in fecal samples. Direct plating samples were streaked for isolation on Sorbitol MacConkey agar with cefixime, and tellurite (SMACct). After incubation overnight at 37°C, morphologically typical colonies from direct streak plates were plated onto blood agar and incubated overnight at 37°C; then an indole test was performed on each colony. Indole-positive colonies were confirmed by O157 agglutination and were then plated on SMAC agar with 20 μg/mL nalidixic acid (SMACnal) to confirm nalidixic acid resistance. Overall sensitivity of detection was 32.5% (110/338 samples). Sensitivity to detect fecal samples shedding at above 5 × 104 cfu/g was 83% (71/86 samples). Based on these data, direct plating of fecal samples might be an effective way to identify cattle that are likely to be shedding E. coli O157 at high levels. [ABSTRACT FROM AUTHOR]

We investigate the relation between diabetes mellitus and risk of prostate cancer among older (age 65-79 years) men in a population-based case-control study of 407 incident histologically confirmed cases registered in the South Carolina Central Cancer Registry between 1999 and 2001 (70.6% response rate); controls were 393 men identified through the Health Care Financing Administration Medicare beneficiary file for South Carolina in 1999 (63.8% response rate). After adjusting for age, race, and prostate cancer screening in the past 5 years, a history of diabetes mellitus was associated with a reduced risk of prostate cancer (adjusted odds ratio (aOR)=0.64; 95% confidence interval (CI)=0.45, 0.91). The protective effect was stronger for those with complications associated with diabetes (aOR=0.61; 95% CI=0.42, 0.90) and for African-American men (aOR=0.36; 95% CI=0.21, 0.62). Additional research is needed to understand the biologic mechanisms by which diabetes may influence prostate cancer risk; genetic factors may play an important role in understanding this association.British Journal of Cancer (2004) 90, 2171-2175. doi:10.1038/sj.bjc.6601857 www.bjcancer.com Published online 4 May 2004 [ABSTRACT FROM AUTHOR]

Many previous assessments of the global hydrogen budget have used assumed global averages of temperatures and levels of key reactants to calculate the magnitudes of the various sinks. Dry deposition is by far the largest hydrogen sink but has not been considered in detail in previous estimates of the hydrogen budget. Simulations of hydrogen using a global three-dimensional Lagrangian chemistry-transport model and two different dry deposition schemes were compared with surface measurements. An improved dry deposition scheme which included the effects of soil moisture gave better agreement between the modelled hydrogen levels and surface measurements. The seasonal variation in the hydrogen levels was also simulated much more accurately with the new dry deposition scheme. The model results at high southern latitudes were insensitive to the relative partitioning of the sources between fossil fuel combustion and biomass burning. The results indicate a global mean hydrogen dry deposition velocity of 5.3×10-4 m s-1 which is lower than the previously used 7×10-4 m s-1. [ABSTRACT FROM AUTHOR]

Big brown bats can discriminate between echoes that alternate in delay (jitter) by as little as 10–15 ns and echoes that are stationary in delay. This delay hyperacuity seems so extreme that it has been rejected in favor of an explanation in terms of artifacts in echoes, most likely spectral in nature, that presumably are correlated with delay. Using different combinations of digital, analog, and cable delays, we dissociated the overall delay of jittering echoes from the size of the analog component of delay, which alone is presumed to determine the strength of the apparatus artifact. The bats' performance remains invariant with respect to the overall delay of the jittering echoes, not with respect to the amount of analog delay. This result is not consistent with the possible use of delay-related artifacts produced by the analog delay devices. Moreover, both electronic and acoustic measurements disclose no spectral cues or impedance-mismatch reflections in delayed signals, just time-delays. The absence of artifacts from the apparatus and the failure of overlap and interference from reverberation to account for the 10-ns result means that closing the gap between the level of temporal accuracy plausibly explained from physiology and the level observed in behavior may require a better understanding of the physiology. [ABSTRACT FROM AUTHOR]

We assessed breast cancer risk in relation to weight at birth and adolescence. In-person interviews were completed with the biological mothers of women aged 45 years and younger who participated in the Shanghai Breast Cancer Study in 1996-98 (288 cases, 350 controls). After adjustment for confounding, women who were 4000 g or more at birth were not at increased risk of breast cancer (odds ratio=0.7; 95% confidence interval 0.4-1.4) relative to women whose birth weight was 2500-2999 g. Compared with women of average perceived weight at age 15 years, no relation was apparent for heavier than average weight based on maternal report (odds ratio=0.7; 95% confidence interval 0.5-1.2) or self-report (odds ratio=1.0; 95% confidence interval 0.7-1.6). Perceived adolescent weight and height did not modify the association of birth weight with breast cancer risk. These results suggest that weight early in life is not related to premenopausal breast cancer risk in this low-risk population. [ABSTRACT FROM AUTHOR]

A routine soil testing procedure for soil N mineralization is needed that is rapid and precise. Not accounting for N mineralization can result in the over-application of N, especially in soils with a history of manure application. Our objectives were to compare results from a recently proposed rapid laboratory procedure with: (1) long-term N mineralization under standard laboratory conditions, and (2) actual forage N uptake from soil receiving dairy cattle ( Bos taurus) manure in a 2-year field study. The rapid procedure is based on the quantity of CO2-C evolved during 24 h under optimum laboratory conditions following the rewetting of dried soil. Dairy cattle manure was surface applied beginning in 1992 at annual rates of 0, 112, 224, or 448 kg N ha–1 to field plots on a Windthorst fine sandy loam soil (fine, mixed, thermic Udic Paleustalf) near Stephenville, Texas (32°N, 98°W). Results of the one-day CO2 procedure were highly correlated with soil N mineralized from samples collected in March of 1995 ( P=0.004) and 1996 ( P<0.001) and with forage N uptake ( P<0.001) both years of the study. Residual inorganic N in the same soil samples was poorly correlated with soil N mineralization and forage N uptake. [ABSTRACT FROM AUTHOR]

A correction to the article "Regional hydrological cycle changes in response to an ambitious mitigation scenario" that was published in the September 6, 2013 issue is presented.

The oxidation behavior of Cu-2Be, Cu-5Al, Cu-8Al, Cu-3Si, Cu-2Al-2Si, Cu-2.5Al-2.5Si, Cu-4.5Al-2Si, Cu-7.5 Al-2Si, Cu-6.5Al-4Si, and Cu-4.5Al-5Si, in the temperature range 100-800°C, in air, has been investigated by gravimetric measurements and by electron microscopical examination of stripped oxide films. Most of the alloys showed considerable resistance to oxidation. This was given mainly by a thermally grown film of γ-alumina on the Cu-Al and Cu-Al-Si alloys and by a beryllia film on the Cu-Be alloy. Other oxide phases, principally copper oxides, were also found to grow on the alloys and these are described. Silicon additions to Cu-Al alloys are found to improve their oxidation resistance, although no crystalline oxides containing silicon were observed in the oxide films stripped from the Cu-Al-Si alloys. [ABSTRACT FROM AUTHOR]

The structure and composition of oxide films formed on Cu-7.5 Al-2 Si in air over the temperature range 100° to 800°C have been studied by transmission electron microscopy of stripped films, replicas, and thin foils. At the highest temperature, the formation of a thin (250Å) film consisting mainly of γ alumina is followed within the first minute by the nucleation of single crystals of cuprous oxide epitaxially oriented to the α phase of the alloy. These grow to a depth of about 6000Å. The location of these crystals and the mechanism by which they are formed, have been studied by experiments involving selective oxidation and short exposure times. An extensive discussion of possible mechanisms is included. While silicon has a beneficial effect upon the oxidation resistance of Cu-Al, no compound of silicon was detected in the oxide films. [ABSTRACT FROM AUTHOR]

Comments on the article of Van Noord regarding preconceptional mitochondrial hypothesis published in the 'British Journal of Cancer.' Link of DNA base excision repair genes to breast cancer risk among daughters born to older mothers; DNA damage in breast cancer tissue; Association of parental age to breast cancer risk.

Setting: Public health practitioners are called to effectively communicate with the public on climate change. The climate crisis requires swift action that starts with public awareness of climate-related health impacts and leads to public support for individual, community and systemic actions to mitigate and adapt to climate change., Intervention: This paper discusses learnings about public opinion research and communication strategies and how a health-focused climate communication campaign-#MakeItBetter-could help to increase awareness and engage new audiences, including public health partners, in conversations about climate change in order to reduce climate-related health impacts for current and future generations. The #MakeItBetter campaign was grounded in evidence-informed messaging, being sensitive to health inequities. Emerging research and pre-campaign testing suggest that framing climate change as a health issue is a promising practice., Outcomes: The #MakeItBetter campaign appeals to parents/caregivers to learn more about climate-related health impacts, take protective action for children and support multi-level climate action. The campaign launch secured 89 news stories, including multicultural media coverage. Longer-term evaluation is required to determine the campaign's effectiveness in building public support for climate action., Implications: An innovative approach to climate communication that draws on the intersections between behavioural and climate sciences and engages in multi-sectoral collaboration can spur both climate action and health protection, aiding public health practitioners and partners in effectively communicating the urgency for climate action. More work is needed to support communication on climate change as an inequity multiplier and promote climate action and community resilience for health equity co-benefits.