SummaryTo determine the role of ethylene during tomato (Lycopersicon esculentum Mill. cv. Ailsa Craig} leaf senescence, transgenic ACC oxidase antisense plants were analysed. Northern analysis of wild-type plants indicated that ACC oxidase mRNA accumulation normally begins in pre-senescent green leaves but was severely reduced in the antisense plants. Although the levels of ethylene evolved by wild-type and transgenic leaves increased during the progression of senescence, levels were extremely low in transgenic leaves. Leaf senescence, as assessed by colour change from green to yellow, was clearly delayed by 10-14 days in the antisense plants when compared with wild-type plants. Northern analysis of the photosynthesis-associated genes, cab and rbcS, indicated that levels of the corresponding mRNAs were higher in transgenic leaves which were not yet senescing compared with senescing wild-type leaves of exactly the same age. Northern analysis using probes for tomato fruit ripening-related genes expressed during leaf senescence indicated that once senescence was initiated the expression pattern of these mRNAs was similar in transgenic and wildtype leaves. In the anticense plants chlorophyll levels, photosynthetic capacity and chlorophyll fluorescence were higher when compared with senescing wild-type plants of the same age. Photosynthetic capacity and the quantum efficiency of photosystem II were maintained for longer in the transformed plants at values close to those observed in wild-type leaves prior to the visible onset of senescence. These results indicate that inhibiting ACC oxidase expression and ethylene synthesis results in delayed leaf senes- cence, rather then inducing a stay-green phenotype. Once senescence begins, it progresses normally. Onset of senescence is not, therefore, related to a critical level of ethylene. The correlation between higher levels prior to senescence and early onset, however, suggests that ethylene experienced by the plant may be a significant contributing factor in the timing of senescence.

Cities and tourism entities invest massive resources into smart system initiatives as information technologies are a key factor for a city’s destination competitiveness. Moreover cities around the world are increasingly recognizing the smart tourism city concept and related strategies as means of optimizing sustainable environments. Particularly for cities facing emerging issues of residents’ negative perceptions towards tourism, smart tourism city empowers a city to rise to this challenge by creating urban spaces that residents and visitors can enjoy together. However, smart tourism city research initiatives still fail to address the full spectrum of related and potential developments. This study presents a conceptual approach to defining smart tourism city: the smart city and its components are defined and contrasted with smart tourism and its components. The resulting convergence—smart tourism city—is then examined in light of a number of pioneering examples of smart tourism cities and its vital roles in the age of sustainable development. The main purpose of this study is to show the interests of locals and tourists context and the roles of ‘smart’ government leadership to researchers and practitioners.

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An indexed rotational immobilization system was developed for supine total body irradiation (TBI). Treatment plans had multi-isocentric volumetric modulated arc therapy (VMAT) beams to the upper body and parallelopposed fields to the lower body, with a 12 Gy prescription dose to > 90% of the body and mean lung dose ∼8 Gy. In the end-to-end test, point dose measurements had < 10% error. Compared to conventional TBI, the VMAT-based TBI technique increased the mean dose to the body by ∼1.0-1.5 Gy and decreased the mean dose to the lung by ∼1.0-1.5 Gy. Overall treatment time was ∼1.5 h, similar to conventional TBI. 2.2. IRIS-VMAT-TBI treatment workflow During simulation, the IRIS was aligned and anchored to the CT couch. The patient was immobilized in a supine position in a Vac-Lok

Purpose: To improve the accuracy of liver tumor localization, this study tests a biomechanical modeling-guided liver cone-beam CT (CBCT) estimation (Bio-CBCT-est) technique, which generates new CBCTs by deforming a prior high-quality CT or CBCT image using deformation vector fields (DVFs). The DVFs can be used to propagate tumor contours from the prior image to new CBCTs for automatic 4D tumor localization. Methods/ Materials: To solve the DVFs, the Bio-CBCT-est technique employs an iterative scheme that alternates between intensity-driven 2D-3D deformation and biomechanical modelingguided DVF regularization and optimization. The 2D-3D deformation step solves DVFs by matching digitally reconstructed radiographs of the 3D deformed prior image to 2D phase-sorted on-board projections according to imaging intensities. This step's accuracy is limited at lowcontrast intra-liver regions without sufficient intensity variations. To boost the DVF accuracy in these regions, we use the intensity-driven DVFs solved at higher-contrast liver boundaries to finetune the intra-liver DVFs by finite element analysis-based biomechanical modeling. We evaluated Bio-CBCT-est's accuracy with seven liver cancer patient cases. For each patient, we simulated 4D cone-beam projections from 4D-CT images, and used these projections for Bio-CBCT-est based image estimations. After Bio-CBCT-est, the DVF-propagated liver tumor/cyst contours were quantitatively compared with the manual contours on the original 4D-CT 'reference' images, using the DICE similarity index, the center-of-mass-error (COME), the Hausdorff distance (HD) and the voxel-wise cross-correlation (CC) metrics. In addition to