The application of time-series MODIS NDVI profiles for the acquisition of crop information across Afghanistan

We investigated and developed a prototype crop information system integrating 250 m Moderate Resolution Imaging Spectroradiometer (MODIS) normalized difference vegetation index (NDVI) data with other available remotely sensed imagery, field data, and knowledge as part of a wider project monitoring opium and cereal crops. NDVI profiles exhibited large geographical variations in timing, height, shape, and number of peaks, with characteristics determined by underlying crop mixes, growth cycles, and agricultural practices. MODIS pixels were typically bigger than the field sizes, but profiles were indicators of crop phenology as the growth stages of the main first-cycle crops (opium poppy and cereals) were in phase. Profiles were used to investigate crop rotations, areas of newly exploited agriculture, localized variation in land management, and environmental factors such as water availability and disease. Near-real-time tracking of the current years’ profile provided forecasts of crop growth stages, early warning of drought, and mapping of affected areas. Derived data products and bulletins provided timely crop information to the UK Government and other international stakeholders to assist the development of counter-narcotic policy, plan activity, and measure progress. Results show the potential for transferring these techniques to other agricultural systems

Survey and monitoring of opium poppy and wheat in Afghanistan: 2003-2009

An integrated application of remote-sensing technology was devised and applied in Afghanistan during 2003–2009 providing critical information on cereal and poppy cultivation and poppy eradication. The results influenced UK and international policy and counter-narcotics actions in Afghanistan

Image segmentation for improved consistency in image-interpretation of opium poppy

The image-interpretation of opium poppy crops from very high resolution satellite imagery forms part of the annual Afghanistan opium surveys conducted by the United Nations Office on Drugs and Crime and the United States Government. We tested the effect of generalization of field delineations on the final estimates of poppy cultivation using survey data from Helmand province in 2009 and an area frame sampling approach. The sample data was reinterpreted from pan-sharpened IKONOS scenes using two increasing levels of generalization consistent with observed practice. Samples were also generated from manual labelling of image segmentation and from a digital object classification. Generalization was found to bias the cultivation estimate between 6.6% and 13.9%, which is greater than the sample error for the highest level. Object classification of image-segmented samples increased the cultivation estimate by 30.2% because of systematic labelling error. Manual labelling of image-segmented samples gave a similar estimate to the original interpretation. The research demonstrates that small changes in poppy interpretation can result in systematic differences in final estimates that are not included within confidence intervals. Segmented parcels were similar to manually digitized fields and could provide increased consistency in field delineation at a reduced cost. The results are significant for Afghanistan’s opium monitoring programmes and other surveys where sample data are collected by remote sensing

Demanding stories: television coverage of sustainability, climate change and material demand

This paper explores the past, present and future role of broadcasting, above all via the medium of television, in shaping how societies talk, think about and act on climate change and sustainability issues. The paper explores these broad themes via a focus on the important but relatively neglected issue of material demand and opportunities for its reduction. It takes the outputs and decision-making of one of the world’s most influential broadcasters, the BBC, as its primary focus. The paper considers these themes in terms of stories, touching on some of the broader societal frames of understanding into which they can be grouped. Media decision-makers and producers from a range of genres frequently return to the centrality of ‘story’ in the development, commissioning and production of an idea. With reference to specific examples of programming, and drawing on interviews with media practitioners, the paper considers the challenges of generating broadcast stories that can inspire engagement in issues around climate change, and specifically material demand. The concluding section proposes actions and approaches that might help to establish material demand reduction as a prominent way of thinking about climate change and environmental issues more widely. This article is part of the themed issue ‘Material demand reduction’

Induction of Germinal Centers by MMTV Encoded Superantigen on B Cells

It has not been established whether an endogenous superantigen (SAg) expressed on B cells can induce germinal centers (GCs). An interesting model is that of mammary tumor virus encoded viral SAgs, which induce vigorous T cell proliferation and are predominantly expressed on activated B cells. We have used this model to analyze the possibility that direct stimulation of Mtv7+ DBA/2 B cells by vSAg-responsive (Vβ6+) BALB/c T cells can give rise to GCs. Injection of BALB/c SCID mice iv with 2 × 106 DBA/2 B cells, together with LPS, followed by 2 × 106 BALB/c T cells induces numerous large splenic GCs within 3–5 days. The GCs are still large on day 7, but are very much reduced by day 10. B cell activation with LPS is needed for this effect. These GCs form in spite of the apparent absence of follicular dendritic cells (FDCs) as judged by staining for several FDC surface markers. Control mice receiving either BALB/c T or DBA/2 B cells + LPS alone or DBA/2 T + B cells + LPS fail to exhibit any GCs on days 3–7. Numerous small clusters of PNA+ cells, but few large GCs are observed when TNF-R(p55)-Ig is also injected, whereas LTβR-Ig treatment impeded the formation of aggregations of these cells even further, leaving scattered PNA+ single cells and very small clumps throughout the white pulp of the spleens. Anti-TNFα had no effect. These results suggest that endogenous vSAg mediated GC formation is independent of antigen trapping by FDCs

Trade unions and precariat in Europe : representative claims

Trade unions have been charged with neglecting labour market ‘outsiders’, while alternative actors have emerged to represent these. In response, unions have stepped up their claim to be representative of all workers, without distinction. We review the theoretical and policy debates on this issue, and argue that representation as such has been under-theorized. We draw on Saward’s concept of ‘representative claims’ to analyse the different grounds for competing assertions of representativeness. We identify four main forms of claims, and illustrate these with empirical examples. We conclude that these different claims are mutually reinforcing in stimulating attention to the outsiders, and in their interaction with institutional settings, they have a performative effect in defining new social actors

Argonne National Laboratory Reports

Test E8 simulated a hypothetical $3/s transient overpower accident in an LMFBR using seven (plutonium, uranium) oxide fuel elements of the FTR type. The test elements were pre-irradiated in the PNL-10 assembly in EBR-II to 5 at.% burnup at 30 kW/m. The pre-irradiation in EBR-II caused a fuel-restructuring range characteristic of a low-to-moderate power microstructure for FTR. Failure predictions indicated that fuel with this microstructural characteristic would fail at a lower energy deposition than fuel irradiated at higher power. Data from test-vehicle sensors, hodoscope, and postmortem examinations were used to construct the sequence of events occurring within the test zone. The sequence occurred incoherently across the test cluster, the initial event occurring abruptly at about 29 times nominal power level at an estimated stored energy of about 925 kJ/kg with 50% of the fuel above the solidus at the suspected failure site. After the initial failure, about 2% of the total mass of test fuel was ejected above the original top of the active fuel column. Sodium voiding occurred rapidly. A fuel-debris blockage also apparently prevented further fuel dispersal. Inherent test-vehicle limitations, loss of flow-tube geometry, and nontypical power generation after failure may have caused a departure from the fuel motion predicted for FTR conditions. No violent fuel-coolant interaction or associated work-energy conversion to the coolant was observed

Development of a rapid semi-automated tool to measure total kidney volume in autosomal dominant polycystic kidney disease

Background Total kidney volume (TKV) is an approved early prognostic marker of progression in autosomal dominant polycystic kidney disease. The approval of tolvaptan for patients with rapid disease progression in Europe requires accurate patient stratification. Current methods of TKV measurement rely on manual segmentation which is time consuming, restricting its clinical use. To address this important clinical challenge we report the development and performance of a semi-automated method (Sheffield TKV tool) to measure TKV in patients with this disease. Methods 1.5T MRI scans were acquired (Siemens Avanto) in 61 adult patients with autosomal dominant polycystic kidney disease. Manual segmentation of the kidneys was performed on T2 true fast imaging with steady state precession MRI. Computational semi-automated segmentation methods were tested in a subgroup of ten patients and the optimum method used in all 61 cases to measure TKV (mL). Manual and semi-automated results were compared by Bland–Altman analyses. Processing time for manual and semi-automated methods were recorded. Findings Our cohort consisted of 29 men and 32 women (mean age 45 years, SD 14). Estimated GFR (eGFR) in patients within 1 month of the MRI ranged between 32 and 138 mL/min. TKV measured by manual segmentation ranged between 258 and 3680 mL. The Sheffield TKV tool performed optimally for calculating TKV, reporting accurate results in 80% of cases compared with manual TKV. Inaccuracies were associated with erroneous inclusion of blood vessels, the renal hilum, or leakage into neighbouring tissues, and overall were more frequent in smaller kidneys. Processing time for TKV with the Sheffield TKV tool was 2–5 min compared with 20–30 min for manual segmentation. Interpretation We describe a new rapid, semi-automated method for measuring TKV on MRI which should be a useful tool for evaluating patients with autosomal dominant polycystic kidney disease. We plan to optimise MRI acquisition sequences and extract the renal hilar volume to improve performance of the Sheffield TKV tool and validate it in another population with autosomal dominant polycystic kidney disease, with the ultimate aim of using it in clinical practice. Funding Insigneo (Institute for in silico medicine) bursary (from Sheffield Teaching Hospitals NHS Foundation Trust), National Institute for Health Research

Increased Frequency and Compromised Function of T Regulatory Cells in Systemic Sclerosis (SSc) Is Related to a Diminished CD69 and TGFβ Expression

Contains fulltext : 80239.pdf (publisher's version ) (Open Access)BACKGROUND: Regulatory T cells (Tregs) are essential in the control of tolerance. Evidence implicates Tregs in human autoimmune conditions. Here we investigated their role in systemic sclerosis (SSc). METHODS/PRINCIPAL FINDINGS: Patients were subdivided as having limited cutaneous SSc (lcSSc, n = 20) or diffuse cutaneous SSc (dcSSc, n = 48). Further subdivision was made between early dcSSc (n = 24) and late dcSSc (n = 24) based upon the duration of disease. 26 controls were studied for comparison. CD3+ cells were isolated using FACS and subsequently studied for the expression of CD4, CD8, CD25, FoxP3, CD127, CD62L, GITR, CD69 using flow cytometry. T cell suppression assays were performed using sorted CD4CD25(high)CD127(-) and CD4CD25(low)CD127(high) and CD3(+) cells. Suppressive function was correlated with CD69 surface expression and TGFbeta secretion/expression. The frequency of CD4(+)CD25(+) and CD25(high)FoxP3(high)CD127(neg) T cells was highly increased in all SSc subgroups. Although the expression of CD25 and GITR was comparable between groups, expression of CD62L and CD69 was dramatically lower in SSc patients, which correlated with a diminished suppressive function. Co-incubation of Tregs from healthy donors with plasma from SSc patients fully abrogated suppressive activity. Activation of Tregs from healthy donors or SSc patients with PHA significantly up regulated CD69 expression that could be inhibited by SSc plasma. CONCLUSIONS/SIGNIFICANCE: These results indicate that soluble factors in SSc plasma inhibit Treg function specifically that is associated with altered Treg CD69 and TGFbeta expression. These data suggest that a defective Treg function may underlie the immune dysfunction in systemic sclerosis

Adaptive response and enlargement of dynamic range

Many membrane channels and receptors exhibit adaptive, or desensitized, response to a strong sustained input stimulus, often supported by protein activity-dependent inactivation. Adaptive response is thought to be related to various cellular functions such as homeostasis and enlargement of dynamic range by background compensation. Here we study the quantitative relation between adaptive response and background compensation within a modeling framework. We show that any particular type of adaptive response is neither sufficient nor necessary for adaptive enlargement of dynamic range. In particular a precise adaptive response, where system activity is maintained at a constant level at steady state, does not ensure a large dynamic range neither in input signal nor in system output. A general mechanism for input dynamic range enlargement can come about from the activity-dependent modulation of protein responsiveness by multiple biochemical modification, regardless of the type of adaptive response it induces. Therefore hierarchical biochemical processes such as methylation and phosphorylation are natural candidates to induce this property in signaling systems.Comment: Corrected typos, minor text revision