Durante los últimos años la creciente demanda por parte del consumidor de alimentos frescos, de primera calidad y listos para preparar y servir, ha generado un cambio importante en la aplicación de técnicas de conservación de alimentos, abriéndose nuevas líneas en el mercado. Ante este reto, la industria ha respondido mediante la elaboración de productos minimamente procesados en fresco. Sin embargo, estos alimentos presentan una vida útil corta, principalmente debido a problemas de pardeamiento. La metodología para controlar este tipo de problema se basa en la utilización de antioxidantes y atmósferas modificadas con bajo nivel de O2. Sin embargo, la sola aplicación de estas tecnologías, en muchos casos, resulta poco efectiva para garantizar una vida útil adecuada del producto minimamente procesado. Por lo tanto, resulta necesario seguir estudiando en el desarrollo y aplicación de otras tecnologías que ayuden a mantener la calidad de estos productos durante periodos adecuados para su comercialización. En este proyecto, se pretende estudiar la efectividad de tratamientos antioxidantes con recubrimientos comestibles y el envasado en atmósferas modificadas `no convencionales¿, con el objetivo de reducir el pardeamiento enzimático en productos como alcachofa, berenjena, manzana y caqui minimamente procesados. / Ghidelli, C. (2014). EFFECT OF SOY PROTEIN-BASED EDIBLE COATINGS WITH ANTIOXIDANT ACTIVITY AND MODIFIED ATMOSPHERE PACKAGING ON THE QUALITY OF FRESH-CUT PRODUCES [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/39104

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Forestry is an important industry in Sweden, with clear-cut as the most commonly used method for harvesting. Here the long-term impact of clear-cut on lake water quality (dissolved organic carbon (DOC), nitrogen, phosphorus and pH) has been investigated, based on 23 lakes sampled during autumn. Data for additional 15 lakes sampled for the Swedish monitoring program were also used. Lakes were classified as 5, 25, 40 and 60 year based on data of the forest age in the catchment, gathered from the Swedish national forest inventory. Clear-cut lakes were classified as 5 years (>20% of the catchment clear-cut during the last 10 years). The results showed that DOC and total nitrogen (TN) concentrations decreased with increasing age of the forests. In clear-cut lakes (5 year) average DOC- (20.5 mg/L) and TN concentrations (477 µg/L) were higher than the average concentration in lakes with older forests (25, 40 and 60 year) (i.e. DOC 13.5 mg/L and TN 351 µg/L). Also the quality of DOC were changing (measured as changes in absorbance at 254) with forest age, with more bioavailable (low molecular weight) DOC in clear-cut lakes. A greater clear-cut area compared to the catchment area did not significantly result in higher concentrations of DOC and TN in clear-cut lakes. In conclusion, the concentration of TN, and the concentration and quality of DOC, in small boreal lakes are affected by clear-cutting and are changing with the age of the forest stand. Thus, highest concentrations and more bioavailable carbon compounds are found in clear-cut lakes where forests recently has been removed (<10 year).

The influence of sucrose as an important factor in the vase-life of cut flowers has been dually noted. Sucrose is actively transported across the cell membrane via a symport system and the membrane-imbedded ATPase enzyme generates the required energy and proton gradient for the process. The activity of this enzyme decreases during the senescence of Petunia petals, concomitant with a decrease in sucrose-uptake in the post-climacteric phase. However, ATP does not appear to be limiting, indicating that a change in proton gradients may be responsible for this phenomenon. In order to study the uptake of sucrose in Petunia corollas various inhibitors of ATPase enzyme activity (DES and sodium orthovanadate) were introduced. The effect of potassium ferricyanide on the disruption of the membranal electro-chemical gradient was also determined. In addition it was found that the plasma membrane redox system seems to be influential in creating the H+-gradient necessary for sucrose-uptake. These effects were also studied in relation to prior treatment of flowers with the hormone, ethylene, for 24 hours. The results obtained have shown the i) importance of a stable inter- and intracellular pH environment; ii) the imbedded ATPase enzyme’s dependence on the membrane stability; iii) the maintenance of the electro-chemical gradient across membranes; the active energy generated by the ATPase enzyme; and lastly, iv) the effect of ethylene directly on membrane integrity and indirectly on sucrose-uptake. / Prof. C.S. Whitehead

The vase life of cut flowers is determined by various physiological factors that determine the rate of their senescence. A thorough understanding of these factors is required in order to design treatments that will extend the vase life and delay senescence of cut flowers. Senescence of climacteric flowers such as carnations (Dianthus caryophyllus L. cv. Nordika and cv. Snow White) and freesias (Freesia refracta cv. Athena) is characterized by a climacteric rise in respiration rate and ethylene synthesis during the late stages. The increase in ethylene production is preceded by an increase in the sensitivity of the flowers to ethylene. Pulse treatments with sucrose caused a delay and suppression of the climacteric rise in ethylene synthesis and a delay in the climacteric maximum of the respiration rate. A pulse treatment for 24 hours with a 20% sucrose solution was most effective in extending the longevity of both carnations and freesias. The ability of the receptor molecules to bind ethylene is greatly reduced when flowers are pulse-treated with sucrose. In freesias, the ability to bind ethylene is reduced even further when flowers are treated with STS or 1-MCP. Ethylene synthesis in freesias is suppressed and inhibited when treated with STS or 1-MCP but longevity of the freesias and number of open florets on the stem is not increased. The uptake and distribution of sucrose in the buds of freesias is seen by the distribution of sucrose from the first bud on the stem to the next bud after the bud opens. The distribution of sucrose from one bud to the next results in more buds opening on the stem than that on the stems of STS or 1-MCP treated freesias. It is thus clear from the results of the study, that pulsing senescing climacteric flowers with sucrose increases the vase life of the flowers and suppresses ethylene sensitivity of the flowers, thus delaying the autocatalytic process of ethylene production. It is also evident from the results that the osmolality in the flowers has a direct influence on the metabolic processes of the flowers. In freesias, pulse treatment with sucrose increases the number of open buds on the stem and delays senescence of the florets. / Mr. C.S. Whitehead

Ardent Dwellings is a work about longing, self-exploration, and construction of identity through the arrangement of meticulously drawn and cut paper elements. Mainly consisting of drawn dried flower forms and expressive female hands, these elements come together in deliberate arrangements of spaces and relations. The moments of sensuality resulting from these exploratory touches signify moments created through traversing bodies and identities. To achieve this exploration visually, I created a collection of eight drawing collages and a large paper installation with mixed media components. The elements in this work are carefully placed in relation to one another with the intent of constructing an abstract narrative exploring the who, how, and the why of the self—specifically the queer self and the search for belonging that accompanies the discovery of this identity. / Includes bibliography. / Thesis (M.F.A.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection

Despite the fact that fish are a common component of coastal and other aquatic archaeological sites, fish bone taphonomy--including bone surface modifications and the effects of burial--remains woefully understudied. Various ethnographic accounts describe fish butchering techniques for immediate consumption and drying, yet cut marks are rarely reported on archaeological fish remains. To address a significant gap in our understanding of fish taphonomy, I devised an experimental research program aimed at assessing whether butchering fish produces cut marks on fish bones and, if so, what factors might account for the discrepancy between the experimental results and the archaeological record. Chapter I provides an introduction to experimental archaeology, including the criticisms and benefits of this approach. Chapter II presents the results of my initial butchery experiment, which establishes that butchering fish can produce abundant cut marks. Chapter III evaluates the effect of the butcher's skill level on the number and distribution of cut marks produced on fish bone during butchery. The results indicate that professional butchers produce nearly 50 percent fewer cut marks than novice- and intermediate-level butchers. Chapter IV addresses the effect of post-depositional taphonomic processes on the long-term visibility of cut marks. Despite a relatively short burial period (27 months), visible cut marks decreased by up to 75 percent, depending on the species. Chapter V is a re-analysis of the fish bone from column E6 at Daisy Cave (CA-SMI-261). Appling the referential framework I acquired through the experiments, I identified 62 cut marks on bones dating from the Early to Late Holocene. A comprehensive understanding of aquatic resource use has implications for a broad range of archaeological topics, including our understanding of hominid diet and resource use; identifying butchery and processing practices among fishing peoples; distinguishing between human and natural agency in the accumulation of fish remains; and assessing questions of behavioral modernity and social complexity. As we continue to recognize the primacy of coastal adaptations throughout human history, it is increasingly critical to expand the breadth of our knowledge regarding the taphonomy of fish remains at archaeological sites. This dissertation includes previously published and unpublished co-authored material.

O presente trabalho tem como objetivos identificar a percepção dos líderes sindicais frente às mudanças que estão sendo propostas na estrutura sindical brasileira e na flexibilização de direitos sociais e compreender o funcionamento das entidades pesquisadas, apresentando suas principais bandeiras de luta e a forma como atuam para alcançá-las. A revisão da literatura estrutura-se em torno das implicações da globalização econômica sobre o processo produtivo e as relações de trabalho, a evolução histórica dos sindicatos brasileiros, as caraterísticas do atual modelo sindical brasileiro e as transformações que estão sendo propostas para mudança desse modelo. A metodologia adotada é a do estudo exploratório descritivo combinado, dividido em duas fases – uma fase qualitativa e outra quantitativa. A análise dos dados identifica a posição das lideranças de dois grupos de sindicatos, um vinculado à Central Única dos Trabalhadores - CUT e outro associado à Força Sindical. A análise é complementada com os dados obtidos nas entrevistas realizadas com uma liderança de cada uma das centrais citadas. A partir dos dados apontados na pesquisa, tecem-se os comentários finais.

Copies of author's previously published articles inserted. / Bibliography: leaves 122-137. / xiv, 158 leaves, [16] leaves of plates : ill. (chiefly col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / 18 species of Eucalyptus were subjected to trials to investigate their suitability for floriculture and the effect of pruning for cut flower production. Post harvest trials were conducted to assess the vase life of cut stems, and the effect of pulsing and simulated transportation on vase life. Species of Eucalyptus were also studied for changes in wax morphology of juvenile foliage with leaf age and for variation in amount and composition of leaf epicuticular wax. Molecular markers were discovered which may facilitate the management of E. gunnii breeding and selection for the cut foliage industry, by providing an initial screen for glaucousness. 12 species were recommened for the cut foliage industry. / Thesis (Ph.D.)--University of Adelaide, Dept. of Horticulture, Viticulture and Oenology, 1999