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[en] To understand traffic-related metal(loid) status and uptake by dominant plants growing naturally in roadside soils in the Tibetan plateau, China, aboveground parts and root samples of three dominant plant species (Kalidium slenderbranch, Stipa purpurea, Kobresia pygmaea) were collected along the Qinghai–Tibet highway, and were analyzed for concentrations of traffic-related metal(loid)s such as chromium (Cr), zinc (Zn), copper (Cu), cadmium (Cd), arsenic (As), and lead (Pb). The results indicated that concentrations of metal(loid)s in plant tissues varied greatly among plant species and sites. Tissue distribution of metal(loid)s was significantly related to distance and demonstrated variability as an exponential function of traffic proximity. It was deduced that Cd in Kalidium slenderbranch and Cu and Zn in S. purpurea were mainly derived from soil; Kalidium slenderbranch and Kobresia pygmaea absorbed Zn, and S. purpurea absorbed Cd, mainly through stomata, from atmospheric deposition; enrichments of Pb and As in S. purpurea presented similar characteristics to those of Cd and Pb in Kobresia pygmaea and were affected by both soil and atmospheric deposition. After excluding the effects of the traffic, the highest value obtained for metal(loid)-translocation capacity (7.51 for translocation factor, TF) was observed for S. purpurea collected from Tuotuohe, while the lowest value for metal(loid)-uptake capacity (0.015 for bioaccumulation factor, BF) was for Kalidium slenderbranch collected from Golmud. The three plant species showed limited soil-to-root transfer of metal(loid)s, possibly due to the high soil pH along the Qinghai–Tibet highway, but demonstrated great potential for metal(loid) transfer from roots to aboveground parts. - Highlights: • Metal(loid) concentrations in plants varied as the exponential function of proximity. • The uptake styles of plant vary with species and metal(loid) types. • The studied plant presented limited BF and high TF.
[en] Measurements of body composition have evident value in evaluating growing children and adolescents, and dual-energy X-ray absorptiometry (DXA) is a tool that provides accurate measurements of whole-body bone mineral content (WBBMC), lean body mass (LBM), and fat mass (FM). To interpret such measurements in the context of ill health, normative values must be available. Such information could be expected to be regionally specific because of differences in ethnic, dietary, and physical activity determinants. In this study, DXA was performed with Hologic densitometers in normal girls (n = 91) and boys (n 88) between 3 and 18 years of age. The derivation of normal ranges is presented for boys and girls. The correlation of the sum of WBBMC, LBM, and FM with directly measured body weight was almost perfect (r > 0.997). As expected, FM and body mass index correlated strongly. The normal values for WBBMC, LBM, and FM from this study are compared with other Canadian data and with published normative data from Argentina and the Netherlands, all of which use different densitometers. The results of this study allow the calculation of z scores for each facet of body composition and facilitate the use of DXA to report routine evaluations of body composition in children and adolescents. (author)
[en] When the radioimmunoassay developed for abscisic acid (ABA) estimation was applied to a plant extract, results appeared overestimated. Purification by thin-layer chromatography established that ABA in its free and alkali-hydrolysable forms constituted only a small part of the immunoreactive material. The major source of the cross-reactivity was a group of polar metabolites, poorly soluble in ether and well recovered by ethyl acetate and butanol. These immunoreactive metabolites were compared with polar metabolites already described in experiments wher e [14C]ABA was fed to plant tissue, particularly with recently identified glucosides of ABA and dihydrophaseic acid
[en] Crown sections of pineapple were inoculated aseptically in Murashige and Skoog (MS) medium with varying levels of benzyl adenine (BA) in combination with napthalene acetic acid (NAA). Callus was induced from crown sections that was grown in MS with 0 ppm BA + 2 ppm NAA, 2 ppm BA + 6 ppm NAA. These calli when grown continuously in the same medium developed profusely into shoots. Callus and shoots developed profusely at medium containing 2 ppm BA + 2 ppm NAA. Calli that were further sub-cultured in MS with 2 ppm BA + 2 ppm NAA produced multiple shoots. Calli and shoots that were further sub-cultured in 0 to 4 ppm BA to 4 to 6 ppm NAA formed roots. Results showed that complete plantlets were produced from crown sections of pineapple variety Queen in MS medium supplemented with the different treatment combinations of BA and NAA. (Author). 9 refs.; 1 fig
[en] Background: To appraise the potential of volumetric modulated arc therapy (VMAT, RapidArc) and proton beams to simultaneously achieve target coverage and enhanced sparing of bone tissue in the treatment of soft-tissue sarcoma with adequate target coverage. Material and methods: Ten patients presenting with soft-tissue sarcoma of the leg were collected for the study. Dose was prescribed to 66.5 Gy in 25 fractions to the planning target volume (PTV) while significant maximum dose to the bone was constrained to 50 Gy. Plans were optimised according to the RapidArc technique with 6 MV photon beams or for intensity modulated protons. RapidArc photon plans were computed with: 1) AAA; 2) Acuros XB as dose to medium; and 3) Acuros XB as dose to water. Results: All plans acceptably met the criteria of target coverage (V95% >90-95%) and bone sparing (D1cm3 <50 Gy). Significantly higher PTV dose homogeneity was found for proton plans. Near-to-maximum dose to bone was similar for RapidArc and protons, while volume receiving medium/low dose levels was minimised with protons. Similar results were obtained for the remaining normal tissue. Dose distributions calculated with the dose to water option resulted 5% higher than corresponding ones computed as dose to medium. Conclusion: High plan quality was demonstrated for both VMAT and proton techniques when applied to soft-tissue sarcoma
[en] This paper presents a synopsis of fractional calculus tools for characterising respiratory mechanics. A discussion on power law impedance, viscoelasticity and tissue heterogeneity is made based on morphological and structural properties of lungs. Although targeted towards respiratory system applications, these tools can serve as a basis for modelling other biological structures as well. The paper underlines the importance of characterising the viscoelastic properties of the respiratory tissue and its time-varying properties as a function of disease progress. Perspectives are suggested for developing models able to mimic disease progression and understand treatment effects for better therapeutic management.
[en] We have obtained MR images of 82 patients with various osseous and soft tissue tumors from April 1987 to May 1988. Seven patients had fluid-fluid levels in tumors on MRI.They included four osseous tumors (three aneurysmal bone cysts and one giant cell tumor), three soft tissue tumors (two malignant fibrous histiocytomas and one schwannoma). Fluid-fluid levels were probably due to intracystic non-coagulated blood. The fluid-fluid levels are thought to represent differentiation of red blood cells and fluid component within cystic cavities. We thought that fluid-fluid levels are very useful for quality diagnosis of osseous and soft tissue tumors. (author)
[en] The field of tissue engineering aims to produce living, biological constructs which possess the appropriate spatial ordering of cells and their extra cellular matrix products. The complexity of a single cell and its interactions in a large collective have made development of useful models to assist in tissue culture difficult, and consequentially most tissue culture endeavors are limited to trial and error approaches. Some cell types display a natural tendency to spontaneously self-assemble into large domains of parallel-oriented cells. In this work, we show that these cell culture systems can be studied in the context of continuous disorder–order phase transformations. We suggest that collective ordering of the cells is controlled by the amount of noise in the walk of the individual cells (directional persistence) because undifferentiated mesenchymal stem cells display a seven-times higher directional persistence than mature fibroblasts and have a 24-times larger final-oriented domain size, an observation that corresponds with collective ordering in self-propelled particle systems. The study of cell culture systems using analogies derived from statistical mechanics yields simple, practical models offering insight into how a long-range order can be obtained in tissue-engineered constructs, providing a new paradigm for managing operations with large collectives of living cells
[en] The goal of our work was to develop a simple method to evaluate a compensation treatment after unplanned treatment interruptions with respect to their tumour- and normal tissue effect. We developed a software tool in java programming language based on existing recommendations to compensate for treatment interruptions. In order to express and visualize the deviations from the originally planned tumour and normal tissue effects we defined the compensability index. The compensability index represents an evaluation of the suitability of compensatory radiotherapy in a single number based on the number of days used for compensation and the preference of preserving the originally planned tumour effect or not exceeding the originally planned normal tissue effect. An automated tool provides a method for quick evaluation of compensation treatments. The compensability index calculation may serve as a decision support system based on existing and established recommendations