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Europium doped calcium titanate (CT:Eu 3+ ) powders containing 0.5%, 1.0% and 2.0% mol of Eu 3+ were syn- thesized by hydrothermal microwave method (HTMW) at 140 C for 10 min resulting in the samples CT:Eu 3+ (0.5%) CT:Eu 3+ (1.0%) and CT:Eu 3+ (2.0%). Eu 3+ ion was introduced into the perovskite lattice aim- ing to study the synthesis, photoluminescence emissions and morphological properties of these powders. X-ray diffraction patterns present a single phase indexed as Pbnm space group in a typical orthorhombic CaTiO3 (CT) structure. FT-Raman spectra of CT indicated a great arrangement in a short range, while UV- vis measurements did not show any substantial changes in the optical absorbance behavior of CT:Eu 3+

The study of the photoluminescent properties affected by order and disorder of the BaMoO(4) powders is the principal objective in this work. BaMoO(4) compounds were prepared using soft chemical process called Complex Polymerization Method. In this work, different deagglomeration types and different heating rates were used to promote different disorder degrees. Scheelite type phase (BaMoO(4)) was determined by X-ray Diffraction (XRD), Fourier Transformed Infra-Red (FTIR) and Raman spectroscopy after heat treating the sample at 400 degrees C. The room temperature luminescence spectra revealed an intense single-emission band in the visible region. Based on XRD and Raman data it was observed that the transition between the completely disordered structure to completely ordered structure is a good condition for photoluminescence (PL) emission. The best PL emission is obtained when the material possesses short range disorder, i.e., is periodically ordered (XRD), but some disorder as measured by Raman spectroscopy. The excellent optical properties observed for disordered BaMoO(4) suggested that this material is a highly promising candidate for optical applications.

Purpose The aim of this study was to compare inverse planning–simulated annealing (IPSA) with geometric optimization (GO) in high-dose-rate (HDR) prostate brachytherapy, to assess variations in dosimetric indices associated to catheter displacement. Methods and Materials We retrospectively studied the dosimetric effect of catheter displacement in 20 patients treated with HDR prostate brachytherapy with salvage intention. The catheter loadings, with optimized dwell positions, from the first fraction were transferred to the catheter positions in the second fraction. Results Median catheter displacement was 8.7 ± 3.3 mm (range, 2.7 ± 1.1 mm–14.7 ± 1.7 mm). D 90% median variations for IPSA and GO were −10% with a maximum of −59%, and −29% with a maximum of −63%, respectively. V 100% median variation was −11% with a maximum of −37% for IPSA, and −20% with a maximum of −37% for GO. V 150 / V 100 implant median variations were 15% and 9% for IPSA and GO with maximum values of 65% and 47%, respectively ( p V 200 / V 100 indices, nor were any significant differences found for organs at risk. Correlation between mean catheter displacement and dosimetric indices was found only in the planning target volume D 90% and V 100% ; linear regression slopes were −2.0% per mm and −2.6% per mm for IPSA vs. −2.4% per mm and −3.5% per mm for GO. Conclusions IPSA does not present any additional risk compared with GO in HDR prostate brachytherapy when catheter uncertainties are taken into account. Moreover, IPSA optimization preserves planning target volume coverage better than GO, suggesting that it may be superior when catheter displacement is considered.

The variations of leaf carbohydrate concentration, carbon isotope discrimination (A) of leaf soluble carbohydrate, gas-exchange and growth during a soil drying cycle under 350 and 700 μmol mol -1 CO 2 concentrations ([CO 2 ]) in Quercus robur seedlings were analysed. In well-watered conditions, a doubling of [CO 2 ] caused an increase of CO 2 assimilation rate (A) (+47%) and a decrease of stomatal conductance for water vapour (g) (-25%), and doubled the intrinsic water-use efficiency (A/g). The values of Δ were not affected by elevated [CO 2 ] which was consistent with the 2-fold increase of A/g. Elevated [CO 2 ] also significantly increased sucrose and starch leaf concentrations as well as aerial growth and plant dry weight. The stimulating effect of CO 2 enrichment on A and A/g was maintained in moderate drought conditions, but disappeared in the most severe drought conditions. Drought induced an increase of hexose concentrations in both [CO 2 ], but this effect was more pronounced under elevated [CO 2 ], which may contribute to increase osmoregulation. From the onset of drought, starch was depleted in both [CO 2 ]. Carbon isotope discrimination decreased in response to drought, which corresponded to an increase in A/g according to the two-step model of isotopic discrimination. In contrast, the A/g values derived from instantaneous leaf gas-exchange measurements decreased along the drying cycle. The discrepancy observed between the two independent estimates of water-use efficiency is discussed in terms of time-scale integration. The results obtained with the isotopic approach using soluble carbohydrate suggest a predominant stomatal limitation of CO 2 assimilation in response to drought.

Using a solvothermal method for this research we synthesized nanocrystalline titanium dioxide (nc-TiO 2 ) anatase particles with a mean diameter of 5.4 nm and evaluated their potential antifungal effect against planktonic cells of Candida albicans without UV radiation. To complement experimental data, we analyzed structural and electronic properties of both the bulk and the (1 0 1) surface of anatase by first-principles calculations. Based on experimental and theoretical results, a reactive O 2 H ∗ and OH ∗ species formation mechanism was proposed to explain the key factor which facilitates the antifungal activity.

Des semis de chene pedoncule (Quercus robur L) ont ete soumis, durant leur premiere saison de vegetation, a des concentrations atmospheriques en CO 2 ([CO 2 ]) ambiantes (350 μmol mol -1 ) ou doublees (700 μmol mol -1 ) en conditions de bonne alimentation hydrique ou de secheresse (fourniture d'eau egale a 40 % de la transpiration des plants bien irrigues pour chacune des conditions de [CO 2 ]). L'humidite ponderale du sol (SWC) etait en moyenne inferieure de 4 10 -2 g g -1 sous [CO 2 ] eleve comparativement a la [CO 2 ] ambiante. En conditions hydriques favorables, l'augmentation de la concentration en CO 2 est a l'origine d'une stimulation de la croissance de 39 %. Cependant le taux de croissance relative (RGR) n'est stimule par l'augmentation de la concentration en CO 2 qu'au cours d'un intervalle de temps de 17 jours, en juillet, correspondant a la fin de la phase d'elongation de la tige (troisieme flush de croissance) et a la phase de vitesse d'expansion foliaire maximale. Le nombre de feuilles ainsi que la surface foliaire par plant sont augmentes de 30 % par l'augmentation de la concentration en CO 2 . En conditions de secheresse, aucune stimulation de croissance ponderale ni de surface foliaire par plant ne sont observees en reponse a l'augmentation de la concentration atmospherique en CO 2 . Le taux de transpiration est reduit par l'augmentation de la concentration en CO 2 , mais la transpiration totale par plant n'est pas affectee par la concentration atmospherique en CO 2 , traduisant une compensation entre augmentation de surface foliaire et fermeture stomatique. L'efficience de transpiration (W = accumulation de biomasse/eau transpiree) est augmentee de 47 % par l'augmentation de la concentration en CO 2 en regime hydrique favorable et seulement de 18 % en regime hydrique limitant. La discrimination isotopique du carbone (Δ) des plants est diminuee par la secheresse et augmentee par le doublement de la concentration en CO 2 . Une relation lineaire negative entre l'efficience de transpiration divisee par la concentration atmospherique en CO 2 et Δ est observee conformement a la theorie (equation 5).

Overexposure to radioactive sources used in radiotherapy or industrial radiography may result in severe health consequences. This report assesses the initial clinical status and the medical and psychological long-term follow-up of two radiation accident patients from Peru during the mid-to-late 1990s: one patient exposed to a radiotherapy (60)Co source in Arequipa, the other patient to a (192)Ir source in Yanango. Commonalities and differences are described. The main causes in both accidents were human error and the failure to apply appropriate safety guidelines and standard operating procedures. Education and training of the personnel working with radiation sources are essential to prevent accidents. The experience gained from the medical management of the two patients is valuable for future treatment of such patients.

International audience; The humid tropics have seen a considerable expansion in ruminant farming since the 1970s (at present 25% of the world’s ruminant stock). This situation is often criticized for its negative environmental impacts: deforestation, loss of biodiversity, greenhouse gas (GHG) production (carbon dioxide, methane, nitrous oxide). The increase of direct emissions from the agriculture sector (17%) mostly occur in emerging countries like Brazil (IPCC, 2007). Although ruminant production systems are viewed as a major source of GHG emissions (18% of global emissions according to FAO soil carbon (C) sequestration (SOC) the world’s permanent pastures could potentially offset up to 4% of the global GHG emissions (Soussana et al., 2009; Steinfeld et al., 2010). This research, started in 2010, aims at identifying the carbon dynamics in pastures and define the management practices likely to compensate a part of the C losses resulting from their establishment

Stereotactic Body Radiation Therapy With Volumetric Modulated Arc Therapy and Flattening Filter-Free Beams in Lowor Intermediate-Risk Prostate Cancer: Early Experience and Quality of Life Assessment in Phase 1-2 Trial F. Ferrer, O. Garin, H.A. Letelier, R. De Blas, A. Boladeras, E. Garcia, E. Zardoya, R. Pineiro, A. Hervas, M. Castells, V. Macias, M. Galdeano, C. Gutierrez, M. Ventura, D. Najjari, E. Martinez, J.F. Suarez, C. Picon, J. Pera, and F. Guedea; Catalan Institute of Oncology, L’Hospitalet-Barcelona, Spain, Health Services Research Group IMIM (Hospital del Mar Research Institute), Barcelona, Spain, Escuela de Medicina, Universidad de Valparaiso, Valparaiso, Chile, Ramon y Cajal Hospital, Madrid, Spain, Bellvitge Hospital, L’Hospitalet-Barcelona, Spain, Salamanca Hospital, Salamanca, Spain, University of Barcelona, L’Hospitalet-Barcelona, Spain

The authors evaluated calculations of Percent Depth Dose (PDD) when the grid size and position were changed in the Cadplan radiotherapy planning system. A Scanditronix diode and a plane parallel ionization chamber were used to obtain measured PDD. The measurements were performed on Clinac 2100 C with 6, 9, 12, 16 and 20 MeV electrons, for all electron applicators and representative clinical fields. Cadplan calculations for electrons are based on a generalized Gaussian pencil beam model. The PDD were extracted from the calculated dose distributions with a variable step (1-1.5 mm) between the points (100 points is the maximum) regardless of the grid size, using the Cadplan dose vertical line utility. The curves showed a good agreement, within /spl plusmn/2 mm or /spl plusmn/3% for all electrons beams. For small grid size (1.25-2.5 mm, used in general for low energy electrons), the PDD were discontinuous and not as smooth as the measured PDD. These discrepancies or discontinuities were in general within /spl plusmn/3% for the fields and energies measured. In conclusion, Cadplan calculations for PDD are in good agreement with measurements. When a small grid size is used, the calculated PDD are not as smooth as the measured PDD.

The authors' purpose was to verify dose distributions and monitor unit calculations for Enhanced Dynamic Wedges (EDW) in the Cadplan radiotherapy planning system. A Scanditronix diode array was used to obtain dose profiles and a cylindrical ionization chamber for point absorbed dose calculations. The measurements were performed on a Clinac 600 (6 MV) and on a Clinac 2100 C (6 and 18 MV) for representative clinical fields. Cadplan calculations for EDW are based on a photon pencil beam model, using Varian Golden Segmented Treatment Table (GSTT). For absorbed dose calculations in reference point, agreement within 1.5% was obtained for 6 MV and within 1% for 18 MV. For high dose and low dose gradient region calculations, agreement within 2.5% was obtained, in general, for all photon beams. For large dose gradient region (>30%/cm), agreement within 2 mm was found if appropriate grid size was used for all photon beams. For low dose and low dose gradient region (i.e. 10/spl times/10 cm/sup 2/); agreement within 3% was obtained for small fields. In conclusion Cadplan calculations for EDW are in good agreement with measurements, and they are at least as good as the hard wedge calculations arc. The difference found for low dose and low gradient region in large fields with EDW is due to the photon pencil beam algorithm used by Cadplan. The same order discrepancies are found for large fields when this model is used.

National audience

Elle affecte directement le fonctionnement des vegetaux et notamment celui des arbres forestiers a travers des effets aboutissant le plus souvent a une augmentation de leur vitesse de croissance. Cet effet a ete mis en evidence pour un grand nombre d’especes forestieres a l’aide d’experimentations basees sur le doublement de la concentration atmospherique en CO2 a partir du niveau actuel (Ceulemans et Mousseau, 1994 ; Saxe et al., 1998). L’effet CO2 est sans doute deja effectif actuellement et constitue un facteur explicatif tres probable dans le determinisme de l’augmentation de la productivite forestiere observee en zone temperee (Spiecker et al., 1996).

The responses of predawn leaf water potential (Ψ wp ), leaf conductance to water vapour diffusion (g), CO 2 assimilation rate (A) and carbon isotope competition (δ 13 C) to a soil drying cycle were assessed in Pinus pinaster, a drought-avoiding species with high stomatal sensitivity to drought, and Quercus petraea, a drought-tolerant species with lower stomatal sensitivity to drought, under present (350 μmol mol -1 ) and elevated (700 μmol mol -1 ) atmospheric CO 2 concentrations ([CO 2 ]). In P. pinaster, decreasing A in response to drought was associated with increasing plant intrinsic water use efficiency (A/g) and with decreasing calculated intercellular [CO 2 ] (C i ), suggesting a stomatal limitation of A. In contrast, in Q. petraea, A/g declined and C i increased during the drying cycle, which suggests a non-stomatal origin for the decrease in A. In P. pinaster, a negative relationship was observed between the gas exchange-derived values of C i /C a and δ 13 C, which conforms to the classical two-step carbon isotope discrimination model. In Q. petraea, the relationship between C i /C a and δ 13 C was positive. Possible causes of this discrepancy are discussed. Lower g values were observed under elevated [CO 2 ] than under present [CO 2 ] in Q. petraea, whereas g was unaffected in P. pinaster. A stimulation of A by elevated [CO 2 ] was found in P. pinaster but not in Q. petraea. In both species, A/g was markedly higher under elevated than under present [CO 2 ]. Whether the differences in the g response to elevated [CO 2 ] found here can be generalized to other drought-avoiding and non-avoiding species remains to be assessed.

The responses of growth and transpiration efficiency (W = biomass accumulation/water consumption) to ambient and elevated atmospheric CO(2) concentrations (350 and 700 micro mol mol(-1), respectively) were investigated under optimal nutrient supply in well-watered and in drought conditions in two temperate-forest tree species: Quercus petraea Liebl. and Pinus pinaster Ait. Under well-watered conditions, doubling the CO(2) concentration for one growing season increased biomass growth by 138% in Q. petraea and by 63% in P. pinaster. In contrast, under drought conditions, elevated CO(2) increased biomass growth by only 47% in Q. petraea and had no significant effect on biomass growth in P. pinaster. Transpiration efficiency was higher in Q. petraea than in P. pinaster in all treatments. This difference was linked (i) to lower carbon isotope discrimination (Delta), and thus lower values of the intercellular/ambient CO(2) concentration (c(i)/c(a)) ratio, in Q. petraea, (ii) to lower values of leaf mass ratio (LMR, leaf mass/whole plant mass), which we suggest was positively related to the proportion of daytime carbon fixation lost by respiration (Phi), in Q. petraea, and (iii) to slightly lower C concentrations in Q. petraea than in P. pinaster. The CO(2)-promoted increase in W was higher in Q. petraea (+80%) than in P. pinaster (+50%), and the difference was associated with a more pronounced decrease in Phi in response to elevated CO(2) in Q. petraea than in P. pinaster, which could be linked with the N dilution effect observed in Q. petraea. Because Phi also directly affects growth, the CO(2)-induced enhancement of Phi in Q. petraea is a crucial determinant of the growth stimulation observed in this species. Leaf gas exchange regulation was not the only factor involved in the responses of growth and W to elevated CO(2) and drought, other physiological processes that have crucial roles include carbon and N allocation and respiration.

The light-response of the apparent quantum yield of photosynthetic O(2) evolution (Phi(O(2) )) under non-photorespiratory conditions was measured together with the photochemical efficiency of PS II (DeltaF/F(m)'), the photochemical efficiency of open PS II reaction centers (F(v)'/F(m)') and the photochemical fluorescence quenching (q(p)) of leaf disks punched from oak leaves of seedlings grown in ambient (350 micro mol mol(-1)) or elevated (700 micro mol mol(-1)) CO(2) in a greenhouse, and from sunlit leaves of mature oak trees (Quercus petraea (Matt.) Liebl.). There were marked differences between seedlings and trees. In seedlings, CO(2) concentration during growth did not modify the light response of photosynthesis or PS II activity. There was a single linear relationship between Phi(O(2) ) and DeltaF/F(m)' in seedling leaves that was independent of the CO(2) concentration imposed during growth. In contrast, this relationship was curvilinear in sunlit leaves of adult trees. In seedling leaves, the decrease in q(p) (i.e., the proportion of open PS II reaction centers) largely accounted for the decrease in DeltaF/F(m)', whereas the decrease in DeltaF/F(m)' in sunlit leaves of mature oak trees was dependent on both q(p) and F(v)'/F(m)'.

Intense and broad visible photoluminescent (PL) band in structurally disordered SrWO4 compounds was observed at room temperature. The polycrystalline scheelite strontium tungstate (SrWO4) samples prepared by the polymeric precursor method at different temperatures of annealing were structurally characterized by x-ray diffraction and Fourier transform Raman spectroscopy measurements. Quantum-mechanical calculations showed that the local disorder in the cluster of the network modifiers Sr has a very important role in the charge transfer. The experimental and theoretical results are in good agreement, indicating that the generation of the intense visible PL band can be related to short-range order-disorder degree in the scheelite structure.

Currently, survival of breast cancer patients with brain metastasis ranges from 2 to 16 months. In experimental brain metastasis studies, only 10% of lesions with the highest permeability exhibited cytotoxic responses to paclitaxel or doxorubicin. Therefore, radiation is the most frequently used treatment, and sensitizing agents, which synergize with radiation, can improve the efficacy of the therapy. In this study we used 435-Br1 cells containing the fluorescent protein (eGFP) gene and the photinus luciferase (PLuc) gene to develop a new brain metastatic cell model in mice through five in vivo/in vitro rounds. BR-eGFP-CMV/Luc-V5 brain metastatic cells induce parenchymal brain metastasis within 60.8 ± 13.8 days of intracarotid injection in all mice. We used this model to standardize a preclinical chemoradiotherapy protocol comprising three 5.5 Gy fractions delivered on consecutive days (overall dose of 16.5 Gy) which improved survival with regard to controls (60.29 ± 8.65 vs. 47.20 ± 11.14). Moreover, the combination of radiotherapy with temozolomide, 60 mg/Kg/day orally for five consecutive days doubled survival time of the mice 121.56 ± 52.53 days (Kaplan-Meier Curve, p < 0.001). This new preclinical chemoradiotherapy protocol proved useful for the study of radiation response/resistance in brain metastasis, either alone or in combination with new sensitizing agents.Currently, survival of breast cancer patients with brain metastasis ranges from 2 to 16 months. In experimental brain metastasis studies, only 10% of lesions with the highest permeability exhibited cytotoxic responses to paclitaxel or doxorubicin. Therefore, radiation is the most frequently used treatment, and sensitizing agents, which synergize with radiation, can improve the efficacy of the therapy. In this study we used 435-Br1 cells containing the fluorescent protein (eGFP) gene and the photinus luciferase (PLuc) gene to develop a new brain metastatic cell model in mice through five in vivo/in vitro rounds. BR-eGFP-CMV/Luc-V5 brain metastatic cells induce parenchymal brain metastasis within 60.8 ± 13.8 days of intracarotid injection in all mice. We used this model to standardize a preclinical chemoradiotherapy protocol comprising three 5.5 Gy fractions delivered on consecutive days (overall dose of 16.5 Gy) which improved survival with regard to controls (60.29 ± 8.65 vs. 47.20 ± 11.14). Moreover, the combination of radiotherapy with temozolomide, 60 mg/Kg/day orally for five consecutive days doubled survival time of the mice 121.56 ± 52.53 days (Kaplan-Meier Curve, p < 0.001). This new preclinical chemoradiotherapy protocol proved useful for the study of radiation response/resistance in brain metastasis, either alone or in combination with new sensitizing agents.