12,306 research outputs found

    Patchy He II reionization and the physical state of the IGM

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    We present a Monte-Carlo model of He II reionization by QSOs and its effect on the thermal state of the clumpy intergalactic medium (IGM). The model assumes that patchy reionization develops as a result of the discrete distribution of QSOs. It includes various recipes for the propagation of the ionizing photons, and treats photo-heating self-consistently. The model provides the fraction of He III, the mean temperature in the IGM, and the He II mean optical depth -- all as a function of redshift. It also predicts the evolution of the local temperature versus density relation during reionization. Our findings are as follows: The fraction of He III increases gradually until it becomes close to unity at zāˆ¼2.8āˆ’3.0z\sim 2.8-3.0. The He II mean optical depth decreases from Ļ„āˆ¼10\tau\sim 10 at zā‰„3.5z\geq 3.5 to Ļ„ā‰¤0.5\tau\leq 0.5 at zā‰¤2.5z\leq 2.5. The mean temperature rises gradually between zāˆ¼4z\sim 4 and zāˆ¼3z\sim 3 and declines slowly at lower redshifts. The model predicts a flattening of the temperature-density relation with significant increase in the scatter during reionization at zāˆ¼3z\sim 3. Towards the end of reionization the scatter is reduced and a tight relation is re-established. This scatter should be incorporated in the analysis of the LyĪ±\alpha forest at zā‰¤3z\leq 3. Comparison with observational results of the optical depth and the mean temperature at moderate redshifts constrains several key physical parameters.Comment: 18 pages, 9 figures; Changed content. Accepted for publication in MNRA

    Arkansas Cotton Variety Test 1999

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    The primary aim of the Arkansas Cotton Variety Test is to provide unbiased data regarding the agronomic performance of cotton varieties in the major cotton growing areas in Arkansas. This information helps seed dealers establish marketing strategies and assists producers in choosing varieties to plant. In this way the annual test facilitates the inclusion of new, improved genetic material into Arkansas cotton production. The 1999 test had 67 entries (including 25 transgenic genotypes and 35 first-year entries), which were evaluated at sixsites in eastern Arkansas. The presence of four transgenic and five first-year entries among the top 10 yielding entries suggests that improvement is being accomplished in varietal development. This report also includes the Mississippi County Variety Test (an on-farm evaluation of selected varieties) and on-farm variety trials conducted by the Cooperative Extension Service

    Application of remote sensing to selected problems within the state of California

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    Specific case studies undertaken to demonstrate the usefulness of remote sensing technology to resource managers in California are highlighted. Applications discussed include the mapping and quantization of wildland fire fuels in Mendocino and Shasta Counties as well as in the Central Valley; the development of a digital spectral/terrain data set for Colusa County; the Forsythe Planning Experiment to maximize the usefulness of inputs from LANDSAT and geographic information systems to county planning in Mendocino County; the development of a digital data bank for Big Basin State Park in Santa Cruz County; the detection of salinity related cotton canopy reflectance differences in the Central Valley; and the surveying of avocado acreage and that of other fruits and nut crops in Southern California. Special studies include the interpretability of high altitude, large format photography of forested areas for coordinated resource planning using U-2 photographs of the NASA Bucks Lake Forestry test site in the Plumas National Forest in the Sierra Nevada Mountains

    Application of remote sensing to selected problems within the state of California

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    There are no author-identified significant results in this report

    Application of remote sensing to selected problems within the state of California

    Get PDF
    There are no author-identified significant results in this report

    Application of remote sensing to selected problems within the state of California

    Get PDF
    There are no author-identified signficant results in this report

    Integration of patient-reported outcome measures with key clinical outcomes after immediate latissimus dorsi breast reconstruction and adjuvant treatment

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    Background: linical evidence on patient-reported outcome measures (PROMS) in breast reconstruction is lacking. The aim of this study was to evaluate PROMs in implant-assisted latissimus dorsi (LDI) or tissue-only autologous latissimus dorsi (ALD) flap reconstruction in relation to complications and adjuvant treatments.Methods: this was a prospective cohort study involving six UK centres. Eligible patients had primary early-stage breast cancer. The European Organization for Research and Treatment of Cancer quality-of-life questionnaire (QLQ)-C30 and QLQ-BR23, Functional Assessment of Cancer Therapyā€”Breast Cancer scale (FACT-B), Body Image Scale, and Hospital Anxiety and Depression Scale were completed before operation and at 3, 6 and 12 months after surgery.Results: a total of 182 patients (82 LDI and 100 ALD) were recruited between 2007 and 2010 with symptomatic (59Ā·9 per cent) or screen-detected (39Ā·6 per cent) cancers. Some 64Ā·3 per cent had lymph node-negative disease; 30 per cent of the LDI group had radiotherapy, compared with 53Ā·0 per cent in the ALD group (P = 0Ā·004). Early complications up to 3 months after surgery were reported in 66 and 51Ā·0 per cent of patients in the LDI and ALD groups respectively (P = 0Ā·062) and long-term complications (4ā€“12 months) in 48 and 45Ā·0 per cent (P = 0Ā·845). Role functioning and pain (P = 0Ā·002 for both) were adversely affected in the ALD group compared with results in the LDI group, with no significant effects of radiotherapy on any health-related quality of life (HRQL). Chemotherapy and early complications adversely affected HRQL, which improved between 3 and 12 months after surgery (P < 0Ā·010 for all).Conclusion: there is evidence of similar HRQL between types of latissimus dorsi breast reconstruction for up to a year after surgery. There appear to be no overarching effects for radiotherapy after mastectomy on the specific HRQL domains studied in the short term. The identification of variables that affect HRQL is important, including their integration into the analysis of PROM

    Calculating Farm Machinery Field Capacities

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    Calculating field capacities is just part of the overall concept of farm machinery management. Successful farm machinery management does not guarantee a profit, but machinery costs are a major expense and they must be monitored and managed. Therefore, the efficient use of farm machinery starts with determining working capacity in conjunction with the amount of work to be accomplished in a timely manner
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