Plants inhabit different environments and have evolved mechanisms to optimise growth within defined temperature ranges. In Arabidopsis thaliana, growth at high temperature (28°C) results in striking ...elongation of stems and increased leaf elevation from the soil surface 1–3. Despite insights into the molecular control of these responses 1–5, their physiological significance remains unknown. Here, we analysed the impact of high temperature-mediated development on plant water use strategy. We present the surprising finding that Arabidopsis plants developed at high temperature (28°C) show increased water loss and enhanced leaf cooling capacity in these conditions, despite producing fewer leaf surface pores (stomata). Our data suggest that plant architectural adaptations to high temperature may enhance evaporative leaf cooling in well-watered environments.
Neuropsychologists often need to estimate the abnormality of an individual patient’s test score, or test score discrepancies, when the normative or control sample against which the patient is ...compared is modest in size. Crawford and Howell The Clinical Neuropsychologist 12 (1998) 482 and Crawford et al. Journal of Clinical and Experimental Neuropsychology 20 (1998) 898 presented methods for obtaining
point estimates of the abnormality of test scores and test score discrepancies in this situation. In the present study, we extend this work by developing methods of setting
confidence limits on the estimates of abnormality. Although these limits can be used with data from normative or control samples of any size, they will be most useful when the sample sizes are modest. We also develop a method for obtaining point estimates and confidence limits on the abnormality of a discrepancy between a patient’s mean score on
k-tests and a test entering into that mean. Computer programs that implement the formulae for the confidence limits (and point estimates) are described and made available.
Nitrogen oxides (NOx) have fallen steadily across the US over the last 15 years. At the same time, NOx concentrations decrease on weekends relative to weekdays, largely without co-occurring changes ...in other gas-phase emissions, due to patterns of diesel truck activities. These trends taken together provide two independent constraints on the role of NOx in the nonlinear chemistry of atmospheric oxidation. In this context, we interpret interannual trends in wintertime ammonium nitrate (NH4NO3) in the San Joaquin Valley of California, a location with the worst aerosol pollution in the US and where a large portion of aerosol mass is NH4NO3. Here, we show that NOx reductions have simultaneously decreased nighttime and increased daytime NH4NO3 production over the last decade. We find a substantial decrease in NH4NO3 since 2000 and conclude that this decrease is due to reduced nitrate radical-initiated production at night in residual layers that are decoupled from fresh emissions at the surface. Further reductions in NOx are imminent in California, and nationwide, and we make a quantitative prediction of the response of NH4NO3. We show that the combination of rapid chemical production and efficient NH4NO3 loss via deposition of gas-phase nitric acid implies that high aerosol days in cities in the San Joaquin Valley air basin are responsive to local changes in NOx within those individual cities. Our calculations indicate that large decreases in NOx in the future will not only lower wintertime NH4NO3 concentrations but also cause a transition in the dominant NH4NO3 source from nighttime to daytime chemistry.
The NASA Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) mission was conducted in two 3-week deployments based in Alaska (April 2008) and western Canada ...(June–July 2008). Its goal was to better understand the factors driving current changes in Arctic atmospheric composition and climate, including (1) influx of mid-latitude pollution, (2) boreal forest fires, (3) aerosol radiative forcing, and (4) chemical processes. The June–July deployment was preceded by one week of flights over California (ARCTAS-CARB) focused on (1) improving state emission inventories for greenhouse gases and aerosols, (2) providing observations to test and improve models of ozone and aerosol pollution. ARCTAS involved three aircraft: a DC-8 with a detailed chemical payload, a P-3 with an extensive aerosol and radiometric payload, and a B-200 with aerosol remote sensing instrumentation. The aircraft data augmented satellite observations of Arctic atmospheric composition, in particular from the NASA A-Train. The spring phase (ARCTAS-A) revealed pervasive Asian pollution throughout the Arctic as well as significant European pollution below 2 km. Unusually large Siberian fires in April 2008 caused high concentrations of carbonaceous aerosols and also affected ozone. Satellite observations of BrO column hotspots were found not to be related to Arctic boundary layer events but instead to tropopause depressions, suggesting the presence of elevated inorganic bromine (5–10 pptv) in the lower stratosphere. Fresh fire plumes from Canada and California sampled during the summer phase (ARCTAS-B) indicated low NOx emission factors from the fires, rapid conversion of NOx to PAN, no significant secondary aerosol production, and no significant ozone enhancements except when mixed with urban pollution.
Cancer patients often develop the potentially debilitating condition of anaemia. Numerous controlled studies indicate that erythropoiesis-stimulating agents (ESAs) can raise haemoglobin levels and ...reduce transfusion requirements in anaemic cancer patients receiving chemotherapy. To evaluate recent safety concerns regarding ESAs, we carried out a meta-analysis of controlled ESA oncology trials to examine whether ESA use affects survival, disease progression and risk of venous-thromboembolic events.
This meta-analysis included studies from the 2006 Cochrane meta-analysis, studies published/updated since the 2006 Cochrane report, and unpublished trial data from Amgen and Centocor Ortho Biotech. The 60 studies analysed (15 323 patients) were conducted in the settings of chemotherapy/radiochemotherapy, radiotherapy only treatment or anaemia of cancer. Data were summarised using odds ratios (ORs) with 95% confidence intervals (CIs).
Results indicated that ESA use did not significantly affect mortality (60 studies: OR=1.06; 95% CI: 0.97-1.15) or disease progression (26 studies: OR=1.01; 95% CI: 0.90-1.14), but increased the risk for venous-thromoboembolic events (44 studies: OR=1.48; 95% CI: 1.28-1.72).
Though this meta-analysis showed no significant effect of ESAs on survival or disease progression, prospectively designed, future randomised clinical trials will further examine the safety and efficacy of ESAs when used according to the revised labelling information.
Titanium and its alloys remain the most popular choice as a medical implant material because of its desirable properties. The successful osseointegration of titanium implants is, however, adversely ...affected by the presence of bacterial biofilms that can form on the surface, and hence methods for preventing the formation of surface biofilms have been the subject of intensive research over the past few years. In this study, we report the response of bacteria and primary human fibroblasts to the antibacterial nanoarrays fabricated on titanium surfaces using a simple hydrothermal etching process. These fabricated titanium surfaces were shown to possess selective bactericidal activity, eliminating almost 50% of Pseudomonas aeruginosa cells and about 20% of the Staphylococcus aureus cells coming into contact with the surface. These nano-patterned surfaces were also shown to enhance the aligned attachment behavior and proliferation of primary human fibroblasts over 10 days of growth. These antibacterial surfaces, which are capable of exhibiting differential responses to bacterial and eukaryotic cells, represent surfaces that have excellent prospects for biomedical applications.
Criteria for mild cognitive impairment (MCI) consider impairment in instrumental activities of daily living (IADL) as exclusionary, but cross-sectional studies suggest that some high-level functional ...deficits are present in MCI. This longitudinal study examines informant-rated IADL in MCI, compared with cognitively normal (CN) older individuals, and explores whether functional abilities, particularly those with high cognitive demand, are predictors of MCI and dementia over a 2-year period in individuals who were CN at baseline.
A sample of 602 non-demented community dwelling individuals (375 CN and 227 with MCI) aged 70-90 years underwent baseline and 24-month assessments that included cognitive and medical assessments and an interview with a knowledgeable informant on functional abilities with the Bayer Activities of Daily Living Scale.
Significantly more deficits in informant-reported IADL with high cognitive demand were present in MCI compared with CN individuals at baseline and 2-year follow-up. Functional ability in CN individuals at baseline, particularly in activities with high cognitive demand, predicted MCI and dementia at follow-up. Difficulties with highly cognitively demanding activities specifically predicted amnestic MCI but not non-amnestic MCI whereas those with low cognitive demand did not predict MCI or dementia. Age, depressive symptoms, cardiovascular risk factors and the sex of the informant did not contribute to the prediction.
IADL are affected in individuals with MCI, and IADL with a high cognitive demand show impairment predating the diagnosis of MCI. Subtle cognitive impairment is therefore likely to be a major hidden burden in society.
The INTEX‐A field mission was conducted in the summer of 2004 (1 July to 15 August 2004) over North America (NA) and the Atlantic in cooperation with multiple national and international partners as ...part of a consortium called ICARTT. The main goals of INTEX‐A were to (1) characterize the composition of the troposphere over NA, (2) characterize the outflow of pollution from NA and determine its chemical evolution during transatlantic transport, (3) validate satellite observations of tropospheric composition, (4) quantitatively relate atmospheric concentrations of gases and aerosols with their sources and sinks, and (5) investigate aerosol properties and their radiative effects. INTEX‐A primarily relied on instrumented DC‐8 and J‐31 aircraft platforms to achieve its objectives. The DC‐8 was equipped to measure detailed gas and aerosol composition and provided sufficient range and altitude capability to coordinate activities with distant partners and to sample the entire midlatitude troposphere. The J‐31 was specifically focused on radiative effects of clouds and aerosols and operated largely in the Gulf of Maine. Satellite products along with meteorological and 3‐D chemical transport model forecasts were integrated into the flight planning process. Intercomparisons were performed to quantify the accuracy of data and to create a unified data set. Satellite validation activities principally focused on Terra (MOPITT, MODIS, and MISR), Aqua (AIRS and MODIS) and Envisat (SCIAMACHY) to validate observations of CO, NO2, HCHO, H2O, and aerosol. Persistent fires in Alaska and NW Canada offered opportunities to quantify emissions from fires and study the transport and evolution of biomass burning plumes. Contrary to expectations, several pollution plumes of Asian origin, frequently mixed with stratospheric air, were sampled over NA. Quasi‐Lagrangian sampling was successfully carried out to study chemical aging of plumes during transport over the Atlantic. Lightning NOx source was found to be far larger than anticipated and provided a major source of error in model simulations. The composition of the upper troposphere was significantly perturbed by influences from surface pollution and lightning. Drawdown of CO2 was characterized over NA and its atmospheric abundance related to terrestrial sources and sinks. INTEX‐A observations provide a comprehensive data set to test models and evaluate major pathways of pollution transport over NA and the Atlantic. This overview provides a context within which the present and future INTEX‐A/ICARTT publications can be understood.
The granulocyte colony-stimulating factor (G-CSF) is utilized to reduce neutropenic complications in patients receiving cancer chemotherapy. This study represents a systematic review and evidence ...summary of the impact of G-CSF support on chemotherapy dose intensity and overall mortality.
All randomized controlled trials (RCTs) comparing chemotherapy with or without G-CSF support and reporting all-cause mortality with at least 2 years of follow-up were sought. Dual-blind data abstraction of disease, treatment, patient and outcome study results with conflict resolution by third party was carried out.
The search revealed 61 randomized comparisons of chemotherapy with or without initial G-CSF support. Death was reported in 4251 patients randomized to G-CSFs and in 5188 controls. Relative risk (RR) with G-CSF support for all-cause mortality was 0.93 (95% confidence interval: 0.90–0.96; P < 0.001). RR for mortality varied by intended chemotherapy dose and schedule: same dose and schedule (RR = 0.96; P = 0.060), dose dense (RR = 0.89; P < 0.001), dose escalation (RR = 0.92; P = 0.019) and drug substitution or addition (RR = 0.94; P = 0.003). Greater RR reduction was observed among studies with longer follow-up (P = 0.02), where treatment was for curative intent (RR = 0.91; P < 0.001), and where survival was the primary outcome (RR = 0.91; P < 0.001).
All-cause mortality is reduced in patients receiving chemotherapy with primary G-CSF support. The greatest impact was observed in RCTs in patients receiving dose-dense schedules.
Sampling seabirds
The vastness of the worlds' oceans makes them difficult to monitor. Seabirds that forage and breed across oceans globally have been recognized as sentinels of ocean health. Sydeman
...et al.
looked across seabird species of both the Northern and Southern Hemispheres and found varying patterns. Northern Hemisphere species exhibited greater signs of stress and reduced breeding success, indicative of low fish resources. Southern Hemisphere species showed less impact on reproductive output, suggesting that the fish populations there have thus far been less disturbed. The differences across hemispheres indicate different strategies for conservation, with active recovery needed in the north and enhanced protection in the south.
Science
, abf1772, this issue p.
980
The breeding success of seabirds is tracking hemispheric differences in ocean warming and human impacts.
Climate change and other human activities are causing profound effects on marine ecosystem productivity. We show that the breeding success of seabirds is tracking hemispheric differences in ocean warming and human impacts, with the strongest effects on fish-eating, surface-foraging species in the north. Hemispheric asymmetry suggests the need for ocean management at hemispheric scales. For the north, tactical, climate-based recovery plans for forage fish resources are needed to recover seabird breeding productivity. In the south, lower-magnitude change in seabird productivity presents opportunities for strategic management approaches such as large marine protected areas to sustain food webs and maintain predator productivity. Global monitoring of seabird productivity enables the detection of ecosystem change in remote regions and contributes to our understanding of marine climate impacts on ecosystems.
PDF
