Projections of climate change impacts on crop yields are inherently uncertain1. Uncertainty is often quantified when projecting future greenhouse gas emissions and their influence on climate2. ...However, multi-model uncertainty analysis of crop responses to climate change is rare because systematic and objective comparisons among process-based crop simulation models1, 3 are difficult4. Here we present the largest standardized model intercomparison for climate change impacts so far. We found that individual crop models are able to simulate measured wheat grain yields accurately under a range of environments, particularly if the input information is sufficient. However, simulated climate change impacts vary across models owing to differences in model structures and parameter values. A greater proportion of the uncertainty in climate change impact projections was due to variations among crop models than to variations among downscaled general circulation models. Uncertainties in simulated impacts increased with CO2 concentrations and associated warming. These impact uncertainties can be reduced by improving temperature and CO2 relationships in models and better quantified through use of multi-model ensembles. Less uncertainty in describing how climate change may affect agricultural productivity will aid adaptation strategy development and policymaking.
Using the RAdial Velocity Experiment fourth data release (RAVE DR4), and a new metallicity calibration that will be also taken into account in the future RAVE DR5, we investigate the existence and ...the properties of supersolar metallicity stars (M/H ... +0.1 dex) in the sample, and in particular in the solar neighbourhood. We find that RAVE is rich in supersolar metallicity stars, and that the local metallicity distribution function declines remarkably slowly up to +0.4 dex. Our results show that the kinematics and height distributions of the supersolar metallicity stars are identical to those of the M/H ... 0 thin-disc giants that we presume were locally manufactured. The eccentricities of the supersolar metallicity stars indicate that half of them are on a roughly circular orbit (e = 0.15), so under the assumption that the metallicity of the interstellar medium at a given radius never decreases with time, they must have increased their angular momenta by scattering at corotation resonances of spiral arms from regions far inside the solar annulus. The likelihood that a star will migrate radially does not seem to decrease significantly with increasing amplitude of vertical oscillations within range of oscillation amplitudes encountered in the disc. (ProQuest: ... denotes formulae/symbols omitted.)
Background: Patients with advanced renal failure are increasingly opting for conservative treatment, yet little is known of their palliative care needs. Methods: We performed a cross-sectional study, ...examining symptom burden and quality of life in patients with advanced renal failure (estimated GFR < 17 mL/min; n = 11). A contemporary cohort with terminal malignancy acted as comparators (n = 11). Symptom burden was scored using an extended Memorial Symptom Assessment Scale Short Form questionnaire. Quality of life was assessed using the Euroqol-5Q questionnaire. Demographic and pathological data, performance status and co-morbidity were also recorded. Results: Baseline characteristics were similar for the two groups. Symptom burden (renal 17; cancer 15; P =NS) and quality of life scores (renal 60; cancer 60; P =NS) were remarkably similar. Both groups reported high levels of psychological distress. Conclusions: Patients with advanced renal failure experience a symptom burden and impairment of quality of life similar to that of patients with terminal malignancy.
Abstract The ability of the immune system to effectively respond to human tumours is a matter of long-term controversy. There is an increasing body of recent evidence to support a role for the immune ...system in eliminating pre-clinical cancers, an old concept termed ‘immunosurveillance’. ‘Immunoediting’ is an updated hypothesis, in which selection pressures applied by the immune response to tumours modulate tumour immunogenicity and growth. Tumour infiltration by immune cells has been shown to have powerful prognostic significance in a host of cancer types. Paradoxically, in some circumstances the immune system can promote tumour development. Cytotoxic therapies, including radiotherapy and chemotherapy, induce potentially immunogenic cell death, releasing tumour-associated antigens in the context of a ‘danger’ signal to the immune system. An understanding of the interaction between immune cells, tumour cells and treatment modalities will therefore guide the future combination of immunotherapy with conventional therapy to achieve optimal anti-tumour effects.
This article summarizes the third step of a research program to identify variables that supplement the predictive power of the the Eastern Cooperative Oncology Group (ECOG) performance status (PS) ...for survival. The objective was to produce a simple, practical, stratification factor for phase III oncology clinical trials involving patients with advanced malignant disease.
A questionnaire was administered to 729 patients with metastatic colorectal or lung cancers. Patients provided a Karnofsky index and appetite rating while physicians provided a survival estimate and the ECOG-PS. Scores for each item were categorized as having a positive, neutral, or negative indication for survival. A patient was classified as having a relatively good prognosis if three or more of the four items showed a positive indication, a bad prognosis if three or more items were negative, and an uncertain prognosis otherwise (Good/Bad/Uncertain GBU index).
The GBU index improved on the prognostic power of a Cox model quartile index and PS alone and increased the accuracy of survival classification estimates by 5% to 10% more than ECOG-PS alone. For patients with PS of 0 or 1, significant survival patterns exist between GBU groups (P=.002 and.0001, respectively).
The GBU index may be recommended as a supplementary stratification factor for certain future phase III trials in metastatic lung or colorectal cancer where patient heterogeneity is a particular concern. The GBU represents a relatively modest increase to the cost and patient burden of a clinical trial given the additional control that is achieved over the potentially confounding concomitant to the treatment variable.
Canada in the Frame explores a photographic collection held at the British Library that offers a unique view of late nineteenth-century and early twentieth-century Canada. The collection, which ...contains in excess of 4,500 images, taken between 1895 and 1923, covers a dynamic period in Canada’s national history and provides a variety of views of its landscapes, developing urban areas and peoples. Colonial Copyright Law was the driver by which these photographs were acquired; unmediated by curators, but rather by the eye of the photographer who created the image, they showcase a grass-roots view of Canada during its early history as a Confederation. Canada in the Frame describes this little-known collection and includes over 100 images from it. The author asks key questions about what it shows contemporary viewers of Canada and its photographic history, and about the peculiar view these photographs offer of a former part of the British Empire in a post-colonial age, viewed from the old ‘Heart of Empire’. Case studies are included on subjects such as urban centres, railroads and migration, which analyse the complex ways in which photographers approached their subjects, in the context of the relationship between Canada, the British Empire and photography.
Scientists with the Agricultural Research Service (ARS) and various government agencies and private institutions have provided a great deal of fundamental information relating spectral reflectance ...and thermal emittance properties of soils and crops to their agronomic and biophysical
characteristics. This knowledge has facilitated the development and use of various remote sensing methods for non-destructive monitoring of plant growth and development and for the detection of many environmental stresses which limit plant productivity. Coupled with rapid advances in computing
and positionlocating technologies, remote sensing from ground-, air-, and space-based platforms is now capable of providing detailed spatial and temporal information on plant response to their local environment that is needed for site specific agricultural management approaches. This manuscript,
which emphasizes contributions by ARS researchers, reviews the biophysical basis of remote sensing; examines approaches that have been developed, refined, and tested for management of water, nutrients, and pests in agricultural crops; and assesses the role of remote sensing in yield prediction.
It concludes with a discussion of challenges facing remote sensing in the future.
Corn (Zea mays L.) grain yields are known to vary from plant to plant, but the extent of this variability across a range of environments has not been evaluated. This study was initiated to evaluate ...by-plant corn grain yield variability over a range of production environments and to establish the relationships among mean grain yield, standard deviation, coefficient of variation, and yield range. A total of forty-six 8- to 30-m corn transects were harvested by plant in Argentina, Mexico, Iowa, Nebraska, Ohio, Virginia, and Oklahoma from 2002 to 2004. By-plant corn grain yields were determined, and the average individual plant yields were calculated. Over all sites in all countries and states, plant-to-plant variation in corn grain yield averaged 2765 kg ha(-1) (44.1 bu ac(-1)). At the sites with the highest average corn grain yield (11 478 and 14 383 kg ha(-1), Parana Argentina, and Phillips, NE), average plant-to-plant variation in yield was 4211 kg ha(-1) (67 bu ac(-1)) and 2926 kg ha(-1) (47 bu ac(-1)), respectively. As average grain yields increased, so did the standard deviation of the yields obtained within each row. Furthermore, the yield range (maximum corn grain yield minus the minimum corn grain yield per row) was found to increase with increasing yield level. Regardless of yield level, plant-to-plant variability in corn grain yield can be expected and averaged more than 2765 kg ha(-1) over sites and years. Averaging yield over distances >0.5 m removed the extreme by-plant variability, and thus, the scale for treating other factors affecting yield should be less than 0.5 m. Methods that homogenize corn plant stands and emergence may decrease plant-to-plant variation and could lead to increased grain yields.
CPT-11 is a potent antitumor agent that is activated by carboxylesterases (CE) and intracellular expression of CEs that can activate the drug results in increased cytotoxicity to the drug. As ...activation of CPT-11 (irinotecan-7-ethyl-10-4-(1-piperidino)-1-piperidinocarbonyloxycamptothecin) by human CEs is relatively inefficient, we have developed enzyme/prodrug therapy approaches based on the CE/CPT-11 combination using a rabbit liver CE (rCE). However, the in vivo application of this technology may be hampered by the development of an immune response to rCE. Therefore, we have developed a mutant human CE (hCE1m6), based on the human liver CE hCE1, that can activate CPT-11 approximately 70-fold more efficiently than the wild-type protein and can be expressed at high levels in mammalian cells. Indeed, adenoviral-mediated delivery of hCE1m6 with human tumor cells resulted in up to a 670-fold reduction in the IC(50) value for CPT-11, as compared to cells transduced with vector control virus. Furthermore, xenograft studies with human tumors expressing hCE1m6 confirm the ability of this enzyme to activate CPT-11 in vivo and induce antitumor activity. We propose that this enzyme should likely be less immunogenic than rCE and would be suitable for the in vivo application of CE/CPT-11 enzyme/prodrug therapy.
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