To rigorously study hot stars, we need to determine their properties as accurately as possible. This thesis focuses on improving the accuracy of parameters of two hot stars and contributes to the collection of stars with more known parameters. While photometric and spectroscopic data sets on hot stars δ Ori A and ω CMa are plentiful, the former is a triple star that suffers from having a faint spectrum of the secondary, which complicates its analysis, and the latter is a Be star, the origin, formation, and long-term variability of whose gaseous envelopes (veils) remain unexplained. Using mathematical techniques (Fourier transforms) and modelling software PHOEBE 1, properties of δ Ori A are determined, and conjecture on the presence of a circumstellar envelope in δ Ori A might be true by considering the shape changes of the Hα line. A conjecture that period changes of ω CMa correlate to the mass of the circumstellar envelopes seems to be proved true by considering variations of radial velocities, V/R ratio, and determining profile line asymmetry. 1

[pt] Este trabalho apresenta o desenvolvimento de um sistema computacional para ser utilizado na diagramação (encaixe) de figuras planas em cartões retangulares na indústria de embalagens de papel. O sistema aparece como o primeiro passo para a automação total da fabricação de embalagens. Consta de quatro subsistemas: a edição de figuras; e edição de cores das arestas destas figuras; a confecção e edição de encaixes,onde se leva em conta a relação entre as cores das arestas das figuras de acordo com diferentes tipos de problema; a saída destes encaixes por plotter. É apresentada uma discussão detalhada sobre os cálculos de distância entre figuras e sua utilização no esquema de encaixe. Uma série de exemplos gráficos e apresentada cobrindo as diversas situações possíveis. / [en] This research work consists of the development of a computer system to be used in the nesting of plane figures on rectangular cardboards in the paper industry. This system is a first step towards the total automation of the manufacture of paper packs. The system consists of four parts: a figure editor; a subsystem for editing the colors of the edges; the nesting subsystem, in which the colors of the edges are taken into account; and a subsystem for outputing the drawings. A detailed discussion on the calculation of the distance between the figures and its influence on the nesting system is presented. Finally, graphical examples which cover the various possible situations are presented.

No description available.

Studien lyfter fritidspersonalens ambitioner gällande det relationsskapande arbetet med eleverna i verksamheten. Forskning beskriver fritidspersonalens omsorgsuppdrag som en helhet där barnen på fritidshemmet skall känna sig trygga och utveckla goda relationer. Studien tar upp relevant forskning som stärker vikten av relationsskapande för elevers lärande och utveckling. Relationsarbetet försvåras av strukturella faktorer som barngruppens storlek, personaltäthet och krav från styrdokumenten. Studiens centrala innehåll lyfter personalens ambitioner och beskriver hur dessa ser ut när strävan möter realitet. Syftet med studien är att undersöka vad fritidspersonalens har för ambitioner gällande relationsarbetet med eleverna samt hur de hanterar situationer som gör att de inte kan nå sina ambitionsnivåer. Undersökningen är utformad av en kvalitativ metod med intervju som redskap där åtta yrkesverksamma pedagoger medverkade. Empirin och resultatet är analyserat utifrån ett relationellt perspektiv. Studiens resultat visar att informanterna ansåg att relationsarbetet är betydelsefullt där ambitionsnivåerna är höga. Tillit och trygghet anses som en central ambition där kommunikation används som medel. Det framgår att informanterna vill möta barnet med ett öppet sinne, där en balansgång mellan att vara personlig men inte för privat blir tydlig. Informanterna lyfter vikten av att jobba relationsskapande för att utveckla jaget hos eleverna där personalen skall utgå från barnets bästa. Studien beskriver hur olika faktorer påverkar deras ambitionsnivåer vilket leder till kompromisser med dessa. När rätt förutsättningar inte finns sänks ambitionerna och personalen belyser värdet av att be om hjälp från sina kollegor och ledning. Resultatet av studien instämmer med undersökningens bakgrund.

Gastroesophageal reflux disease (GERD), or acid reflux, affects 6-9 million people in the United States. It is characterized by a reflux of gastric acid and bile salts from the stomach into the esophagus, causing injuries to the esophagus known as Barrett's esophagus (BE). BE is the main risk factor for the development of esophageal adenocarcinoma (EAC), a devastating cancer in the esophagus whose molecular roots remain poorly understood. In recent years, evidence points to the esophageal epithelium itself as responsible for causing and promoting inflammation upon injury by gastric reflux, namely via an increase in inflammatory cytokine secretion. This project was focused on a cytokine of interest, Activin A, which is known for its importance during embryogenesis and stem cell differentiation. It has recently been studied for its role in inflammation and tumor formation, but not in the case of esophageal diseases. Here, we demonstrate that Activin A signaling in esophageal epithelial cells is heavily upregulated shortly after exposure to bile salts and acid. We show evidence that this upregulation causes an increase in cell migration upon a reconstituted extracellular matrix. We also provide further evidence that bile and acid injury causes epithelial cells to secrete cytokines, which drive inflammation. We show that the upregulated Activin A secretion and signaling plays an important role in promoting this inflammatory state. Finally, we provide evidence that bile salts and acid exposure, as well as increased Activin A signaling, causes esophageal epithelial cells to upregulate stem cell and transdifferentiation markers, supporting the latest theories on the origin of Barrett' esophagus stem cells as well as paligenosis.

No description available.

No description available.

No description available.

No description available.

No description available.