Patient reported upper gastro-intestinal symptoms associated with fractionated image-guided conformal radiotherapy for metastatic spinal cord compression

Background and purpose Palliative radiotherapy is given to sustain or improve quality of life for patients with advanced cancer. Radiotherapy may however result in symptomatic side effects, which may affect the patient negatively. This prospective longitudinal study of 30 patients aimed at investigating the incidence and severity of early toxicity, particularly focusing on dysphagia, esophagitis and mucositis, following fractionated radiotherapy for cervical and thoracic metastatic spinal cord compression (MSCC), as well as determining the relationship between esophageal dose and early upper gastro-intestinal symptoms. Materials and methods Thirty patients receiving radiotherapy of 3Gyx10 for MSCC were included in the study. Patients were assessed for a total of 7 weeks from onset of radiotherapy using the Edmonton Symptom Assessment System (ESAS) questionnaire. Upper gastro-intestinal symptoms and severity were assessed from the tenth and eleventh question section of the ESAS questionnaire of “other problems” and how much this affected them. The relationships between the mean and maximum esophageal doses and incidence of dysphagia, esophagitis or mucositis were estimated and dose response curves determined. Results Eleven patients reported esophageal symptoms (average duration eleven days, range 1–18 days). Incidence of esophageal toxicity in patients treated at Th8 or above was 79 percent, while no patients treated below Th8 reported any symptoms (p < 0.001). Furthermore, 2 out of 3 patients irradiated at the cervical region reported substantial changes in taste sensation. Risk of symptoms correlated with both mean and maximum esophageal dose and may be a useful tool in planning radiotherapy for MSCC, potentially reducing early upper gastro-intestinal toxicity

Freshwater flux to Sermilik Fjord, SE Greenland

Terrestrial inputs of freshwater flux to Sermilik Fjord, SE Greenland, were estimated, indicating ice discharge to be the dominant source of freshwater. A freshwater flux of 40.4 &amp;plusmn; 4.9&amp;times;10&lt;sup&gt;9&lt;/sup&gt; m&lt;sup&gt;3&lt;/sup&gt; y&lt;sup&gt;−1&lt;/sup&gt; was found (1999–2008), with an 85% contribution originated from ice discharge (65% alone from Helheim Glacier), 11% from terrestrial surface runoff (from melt water and rain), 3% from precipitation at the fjord surface area, and 1% from subglacial geothermal and frictional melting due to basal ice motion. The results demonstrate the dominance of ice discharge as a primary mechanism for delivering freshwater to Sermilik Fjord. Time series of ice discharge for Helheim Glacier, Midgård Glacier, and Fenris Glacier were calculated from satellite-derived average surface velocity, glacier width, and estimated ice thickness, and fluctuations in terrestrial surface freshwater runoff were simulated based on observed meteorological data. These simulations were compared and bias corrected against independent glacier catchment runoff observations. Modeled runoff to Sermilik Fjord was variable, ranging from 2.9 &amp;plusmn; 0.4&amp;times;10&lt;sup&gt;9&lt;/sup&gt; m&lt;sup&gt;3&lt;/sup&gt; y&lt;sup&gt;−1&lt;/sup&gt; in 1999 to 5.9 &amp;plusmn; 0.9&amp;times;10&lt;sup&gt;9&lt;/sup&gt; m&lt;sup&gt;3&lt;/sup&gt; y&lt;sup&gt;−1&lt;/sup&gt; in 2005. The sub-catchment runoff of the Helheim Glacier region accounted for 25% of the total runoff to Sermilik Fjord. The runoff distribution from the different sub-catchments suggested a strong influence from the spatial variation in glacier coverage, indicating high runoff volumes, where glacier cover was present at low elevations

A compositional turnover zone of biogeographical magnitude within lowland Amazonia

Aim To assess the relative roles of geologically defined terrain types ( environmental heterogeneity) and a major river ( physical dispersal barrier) as predictors of ecological structuring and biogeographical differentiation within Amazonian forests.Location Western Brazilian Amazonia, where the Jurua river and its terraces cross a 1000-km-long boundary between two geological formations ( the Solimoes and Ica Formations).Methods We sampled a 500-km stretch of the Jurua with 71 transects ( 5 m by 500 m) that spanned both the river and the geological boundary. All transects were inventoried for pteridophytes ( ferns and lycophytes) and Melastomataceae, and a subset of 39 transects also for palms and Zingiberales. Three surface soil samples were collected from each transect. The data were analysed using ordinations, regression trees, indicator species analyses and Mantel tests.Results All plant groups showed congruent species turnover between geologically defined terrain types, but little evidence of isolation by the river or geographical distance. Soil cation concentration differed between the Solimoes Formation and other terrain types and emerged as the main explanatory factor for species turnover. A large proportion of the plant species were significant indicators for specific parts of the soil cation concentration gradient, and these edaphic associations were congruent with those found in other parts of Amazonia. Pteridophytes had a larger proportion of species in the cation-rich soils than the other plant groups did, and palms had a higher proportion of generalists.Main conclusions The geological boundary between the Solimoes and Ica formations is confirmed as significant floristic turnover zone. As it runs in a north-south orientation for more than 1000 km, the edaphic differences associated with this boundary have wide-ranging implications for speciation and biogeographical patterns in Amazonia

In-medium modifications of the ππ\pi\pi interaction in photon-induced reactions

Differential cross sections of the reactions $(\gamma,\pi^\circ\pi^\circ)$ and $(\gamma,\pi^\circ\pi^++\pi^\circ\pi^-)$ have been measured for several nuclei ($^1$H,$^{12}$C, and $^{\rm nat}$Pb) at an incident-photon energy of $E_{\gamma}$=400-460 MeV at the tagged-photon facility at MAMI-B using the TAPS spectrometer. A significant nuclear-mass dependence of the $\pi\pi$ invariant-mass distribution is found in the $\pi^\circ\pi^\circ$ channel. This dependence is not observed in the $\pi^\circ\pi^{+/-}$ channel and is consistent with an in-medium modification of the $\pi\pi$ interaction in the $I$=$J$=0 channel. The data are compared to $\pi$-induced measurements and to calculations within a chiral-unitary approach

Using digital soil maps to infer edaphic affinities of plant species in Amazonia: Problems and prospects

Amazonia combines semi-continental size with difficult access, so both current ranges of species and their ability to cope with environmental change have to be inferred from sparse field data. Although efficient techniques for modeling species distributions on the basis of a small number of species occurrences exist, their success depends on the availability of relevant environmental data layers. Soil data are important in this context, because soil properties have been found to determine plant occurrence patterns in Amazonian lowlands at all spatial scales. Here we evaluate the potential for this purpose of three digital soil maps that are freely available online: SOTERLAC, HWSD, and SoilGrids. We first tested how well they reflect local soil cation concentration as documented with 1,500 widely distributed soil samples. We found that measured soil cation concentration differed by up to two orders of magnitude between sites mapped into the same soil class. The best map-based predictor of local soil cation concentration was obtained with a regression model combining soil classes from HWSD with cation exchange capacity (CEC) from SoilGrids. Next, we evaluated to what degree the known edaphic affinities of thirteen plant species (as documented with field data from 1,200 of the soil sample sites) can be inferred from the soil maps. The species segregated clearly along the soil cation concentration gradient in the field, but only partially along the model-estimated cation concentration gradient, and hardly at all along the mapped CEC gradient. The main problems reducing the predictive ability of the soil maps were insufficient spatial resolution and/or georeferencing errors combined with thematic inaccuracy and absence of the most relevant edaphic variables. Addressing these problems would provide better models of the edaphic environment for ecological studies in Amazonia