11C-PET imaging reveals transport dynamics and sectorial plasticity of oak phloem after girdling

Carbon transport processes in plants can be followed non-invasively by repeated application of the short-lived positron-emitting radioisotope (11)C, a technique which has rarely been used with trees. Recently, positron emission tomography (PET) allowing 3D visualization has been adapted for use with plants. To investigate the effects of stem girdling on the flow of assimilates, leaves on first order branches of two-year-old oak (Quercus robur L.) trees were labeled with (11)C by supplying (11)CO2-gas to a leaf cuvette. Magnetic resonance imaging gave an indication of the plant structure, while PET registered the tracer flow in a stem region downstream from the labeled branches. After repeated pulse labeling, phloem translocation was shown to be sectorial in the stem: leaf orthostichy determined the position of the phloem sieve tubes containing labeled (11)C. The observed pathway remained unchanged for days. Tracer time-series derived from each pulse and analysed with a mechanistic model showed for two adjacent heights in the stem a similar velocity but different loss of recent assimilates. With either complete or partial girdling of bark within the monitored region, transport immediately stopped and then resumed in a new location in the stem cross-section, demonstrating the plasticity of sectoriality. One day after partial girdling, the loss of tracer along the interrupted transport pathway increased, while the velocity was enhanced in a non-girdled sector for several days. These findings suggest that lateral sugar transport was enhanced after wounding by a change in the lateral sugar transport path and the axial transport resumed with the development of new conductive tissue.We thank the Research Foundation – Flanders (FWO) for the PhD funding granted to Veerle De Schepper, the scientific research committee (CWO) of the Faculty of bioscience engineering (UGent) to support the research visit of Veerle De Schepper at the Forschungszentrum Jülich and the Special Research Fund (B.O.F.) of Ghent University for the post-doc funding granted to Veerle De Schepper

Influence of Melt-Pool Stability in 3D Printing of NdFeB Magnets on Density and Magnetic Properties

The current work presents the results of an investigation focused on the influence of process parameters on the melt-track stability and its consequence to the sample density printed out of NdFeB powder. Commercially available powder of Nd7.5Pr0.7Fe75.4Co2.5B8.8Zr2.6Ti2.5 alloy was investigated at the angle of application in selective laser melting of permanent magnets. Using single track printing the stability of the melt pool was investigated under changing process parameters. The influence of changing laser power, scanning speed, and powder layer thickness on density, porosity structure, microstructure, phase composition, and magnetic properties were investigated. The results showed that energy density coupled with powder layer thickness plays a crucial role in melt-track stability. It was possible to manufacture magnets of both high relative density and high magnetic properties. Magnetization tests showed a significant correlation between the shape of the demagnetization curve and the layer height. While small layer heights are beneficial for sufficient magnetic properties, the remaining main parameters tend to affect the magnetic properties less. A quasi-linear correlation between the layer height and the magnetic properties remanence (Jr), coercivity (HcJ) and maximum energy product ((BH)max) was found

Retrospective evaluation of whole exome and genome mutation calls in 746 cancer samples

Funder: NCI U24CA211006Abstract: The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) curated consensus somatic mutation calls using whole exome sequencing (WES) and whole genome sequencing (WGS), respectively. Here, as part of the ICGC/TCGA Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium, which aggregated whole genome sequencing data from 2,658 cancers across 38 tumour types, we compare WES and WGS side-by-side from 746 TCGA samples, finding that ~80% of mutations overlap in covered exonic regions. We estimate that low variant allele fraction (VAF < 15%) and clonal heterogeneity contribute up to 68% of private WGS mutations and 71% of private WES mutations. We observe that ~30% of private WGS mutations trace to mutations identified by a single variant caller in WES consensus efforts. WGS captures both ~50% more variation in exonic regions and un-observed mutations in loci with variable GC-content. Together, our analysis highlights technological divergences between two reproducible somatic variant detection efforts

Application of net marketing a distribution's company

Orientador: Antonio BatocchioDissertação (mestrado profissional) - Universidade Estadual de Campinas, Faculdade de Engenharia MecanicaResumo: Nas últimas décadas e mais fortemente no início do século XXI, tem se presenciado uma maior projeção, uma maior compreensão e uma maior aceitação do Marketing de Rede de Distribuição como um negócio e um processo de distribuição, divulgação e comercialização de produtos e serviços que pode ser adotado por quaisquer dos segmentos da economia. Esta realidade quanto ao número crescente de empresas que estão adotando este processo de distribuição, quer seja por estruturação de sistemas próprios, quer seja por se utilizarem de parceria com empresas que já desenvolvem Marketing de Rede de Distribuição, é constatada diante da quantidade real de negócios que surgem a cada dia e em setores da economia como indústria, comércio e prestação de serviços. Como quaisquer outras atividades comerciais, a implementação de um processo de distribuição no formato de Marketing de Rede de Distribuição requer um mínimo de conhecimento que são essenciais para garantir maiores probabilidades de sucesso quanto ao desenvolvimento, lucro e continuidade do empreendimento. Isto posto, este trabalho tem por objetivo discutir conceitos, técnicas, sistemas aplicáveis, aspectos legais, eficácia do processo, capacidade de geração de resultados e impacto econômico e social que o Marketing de Rede de Distribuição pode promover numa economiaAbstract: In the last decades and stronger in the beginning of century XXI, we have witnessed a bigger projection, a bigger understanding and a bigger acceptance of the Marketing of Distribution¿s Net as a business and a process of distribution, spreading and commercialization of products and services that can be adopted by any of the segments of the economy. This reality in the aspect of the increasing number of companies that are adopting this process of distribution, either for organization of proper systems, or for its using of partnership with companies that already develop the Marketing of Distribution¿s Net, is evidenced by the amount real business that appears each day and in parts of the economy as industry, commerce and rendering of services. As any other commercial activities, the implementation of a process of distribution in the format of Marketing of Distribution¿s Net requires a minimum of knowledge that are essential to guarantee bigger probabilities of success on the development, profit and continuity of the enterprise. With this analysis, this work wishes to discuss concepts, techniques, the applying system, legal aspects, effectiveness of the process, capacity of promoting results and the economic and social impact that the Marketing of Distribution¿s Net can generate in any economyMestradoGestão da Qualidade TotalMestre em Engenharia Mecânic