824 research outputs found
Analysis of scanner data for crop inventories
There are no author-identified significant results in this report
Wood and Paper Properties of Vacuum Airlift Segregated Juvenile Poplar Whole-Tree Chips
Whole-tree chips from a hybrid poplar clone (Populus 'Tristis #1') grown under short rotation, intensive culture (SRIC) were separated into three fractions using vacuum airlift segregation (VAS). The fractions were: accepts, which was predominantly a woody fraction; rejects, which contained less wood and more bark and twigs; and fines, which consisted mostly of bark particles. The raw material quality was evaluated and kraft pulp and paper properties were determined on the whole-tree chips and each VAS fraction as well as on a 50:50 mixture of the accepts: rejects fractions. A 50:50 mixture of VAS accepts and 55-yr-old mill-run jack pine was also studied. Pulp and paper properties of the whole-tree chips, the VAS accepts and rejects, and a 50:50 mixture of accepts:rejects were similar and were only slightly lower in quality than those of mature aspen chips. The 50:50 mixture of VAS accepts and mill-run jack pine was acceptable by industrial standards. These results suggest that whole-tree chips from SRIC poplar stands can be mixed with conifer chips to supplement furnishes for kraft pulping
Rotating strings
Analytical expressions are provided for the configurations of an
inextensible, flexible, twistable inertial string rotating rigidly about a
fixed axis. Solutions with trivial radial dependence are helices of arbitrary
radius and pitch. Non-helical solutions are governed by a cubic equation whose
roots delimit permissible values of the squared radial coordinate. Only curves
coplanar with the axis of rotation make contact with it.Comment: added to discussion and made small revisions to tex
Detection of the PAX3-FKHR fusion gene in paediatric rhabdomyosarcoma: a reproducible predictor of outcome?
Rhabdomyosarcoma has 2 major histological subtypes, embryonal and alveolar. Alveolar histology is associated with the fusion genes PAX3-FKHR and PAX7-FKHR. Definition of alveolar has been complicated by changes in terminology and subjectivity. It is currently unclear whether adverse clinical behaviour is better predicted by the presence of these fusion genes or by alveolar histology. We have determined the presence of the PAX3/7-FKHR fusion genes in 91 primary rhabdomyosarcoma tumours using a combination of classical cytogenetics, FISH and RT-PCR, with a view to determining the clinical characteristics of tumours with and without the characteristic translocations. There were 37 patients with t(2;13)/PAX3-FKHR, 8 with t(1;13) PAX7-FKHR and 46 with neither translocation. One or other of the characteristic translocations was found in 31/38 (82%) of alveolar cases. Univariate survival analysis revealed the presence of the translocation t(2;13)/PAX3-FKHR to be an adverse prognostic factor. With the difficulties in morphological diagnosis of alveolar rhabdomyosarcoma on increasingly used small needle biopsy specimens, these data suggest that molecular analysis for PAX3-FKHR will be a clinically useful tool in treatment stratification in the future. This hypothesis requires testing in a prospective study. Variant t(1;13)/PAX7-FKHR appears biologically different, occurring in younger patients with more localised disease. Š 2001 Cancer Research Campaignhttp://www.bjcancer.co
Can additive beta-diversity be reliably partitioned into nestedness and turnover components?
Aims: Quantifying βâdiversity (differences in the composition of communities) is central to many ecological studies. There are many βâdiversity metrics, falling mostly into two approaches: varianceâbased (e.g., the Sørensen index), or diversity partitioning (e.g., additive βâdiversity). The former cannot be used when speciesâsites matrices are unavailable (which is often the case in island biogeography in particular) and only species richness data are provided. Recently, efforts have been made to partition additive βâdiversity, a metric calculated using only Îąâdiversity and Îłâdiversity, into nestedness and turnover components (termed here ârichnessâonly βâdiversity partitioningâ). We set out to test whether this form of βâdiversity partitioning generates interpretable results, comparable with metrics based on species incidence βâdiversity partitioning.
Location: Global.
Time period: Present day.
Major taxa studied: Multiple taxa.
Methods: We first provide a brief review of βâdiversity partitioning methods, with a particular focus on the development of richnessâonly βâdiversity partitioning. Second, we use 254 empirical incidence matrices (provided with the paper) sourced from the literature to measure turnover and nestedness using incidence βâdiversity partitioning, comparing the resulting values with those calculated using richnessâonly βâdiversity.
Results: We provide an account of the emergence of βâdiversity partitioning, with particular reference to the analysis of richnessâonly datasets, and to the definition and usage of the relevant metrics. Analytically, we report weak correlations between turnover and nestedness calculated using the two different approaches. We show that this is because identical values of Îąâdiversity and Îłâdiversity can correspond to incidence matrices with a range of different structures.
Main conclusions: Our results demonstrate that the use of richnessâonly βâdiversity partitioning to measure turnover and nestedness is problematic and can produce patterns unrelated to conventional measures of turnover and nestedness. We therefore recommend that more accurate definitions are adopted for these terms in future studies.</br
Intensity Modulated Radiotherapy (IMRT) and Fractionated Stereotactic Radiotherapy (FSRT) for children with head-and-neck-rhabdomyosarcoma
<p>Abstract</p> <p>Background</p> <p>The present study evaluates the outcome of 19 children with rhabdomyosarcoma of the head-and-neck region treated with Intensity Modulated Radiotherapy (IMRT) or Fractionated Stereotactic Radiotherapy (FSRT) between August 1995 and November 2005.</p> <p>Methods</p> <p>We treated 19 children with head-and-neck rhabdomyosarcoma with FSRT (n = 14) or IMRT (n = 5) as a part of multimodal therapy. Median age at the time of radiation therapy was 5 years (range 2â15 years). All children received systemic chemotherapy according to the German Soft Tissue Sarcoma Study protocols.</p> <p>Median size of treatment volume for RT was 93,4 ml. We applied a median total dose of 45 Gy (range 32 Gy â 54 Gy) using a median fractionation of 5 Ă 1,8 Gy/week (range 1,6 Gy â 1,8 Gy).</p> <p>The median time interval between primary diagnosis and radiation therapy was 5 months (range 3â9 months).</p> <p>Results</p> <p>After RT, the 3- and 5-year survival rate was 94%. The 3- and 5-year actuarial local control rate after RT was 89%.</p> <p>The actuarial freedom of distant metastases rate at 3- and 5-years was 89% for all patients.</p> <p>Radiotherapy was well tolerated in all children and could be completed without interruptions > 4 days. No toxicities >CTC grade 2 were observed. The median follow-up time after RT was 17 months.</p> <p>Conclusion</p> <p>IMRT and FSRT lead to excellent outcome in children with head-and-neck RMS with a low incidence of treatment-related side effects.</p
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