963 resultados para Preservation of embryo
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Foeniculum vulgare Mill. (fennel) and Matricaria recutita L. (chamomile) are two examples of plants with reported antioxidant and antimicrobial properties, which can be related with their composition in phenolic compounds [1,2]. Furthermore, according to previous results of our research group, the direct incorporation of the aqueous extracts showed capacity to maintain the nutritional properties of the cottage cheeses, up to 7 days of storage, while improving the antioxidant potential. However, after 14 days, a decrease in the antioxidant properties was observed [1,2], which can be related with factors such as light, moisture, temperature and pH, that can cause bioactive compounds degradation. Therefore, the aim of the present study was to prepare microcapsules with the aqueous extracts of fennel and chamomile for incorporation in cottage cheese samples, in order to protect the bioactive molecules present in the extracts, such as phenolic compounds, and prevent the decrease of the antioxidant activity observed after the 14 days period. The microspheres were prepared using an atomization/coagulation technique. Sodium alginate was used as the matrix material to produce the microspheres that were characterized through optical microscopy (OM), during and after atomization, for inspecting morphology. The encapsulation efficiency (EE) was determined by HPLC-DAD by an indirect method by analysing the coagulation solution. FTIR was also used to attest the presence of the extract inside of the alginate matrix. These microencapsulated extracts were incorporated in cottage cheese samples that were further characterized in terms of nutritional properties and antioxidant potential right after incorporation, and after 7 and 14 days of storage at 4•c. The EE was estimated as -100% and the FTIR analysis confirmed the presence of the extracts inside the microspheres. The results showed that the incorporation of the microencapsulated extracts did not cause changes in the nutritional value of cottage cheeses (through a comparison with control samples without extracts). The predominant fatty acids were palmitic (C16:0) and oleic (CI8:0) acids. The order of abundance of fatty acids was as follows: saturated fatty acids (SF A)> monounsaturatcd fatty acids (MUF A)> polyunsaturated fatty acids (PUF A). Regarding free sugars, lactose was the only sugar identified and quantified in all samples. Regarding the antioxidant activity, the samples functionalized with the microencapsulated extracts showed a higher preservation of this property even after the 7th day of storage. Overall, the incorporation of the protected plant extracts in dairy foods can be a strategy to provide health benefits to consumers.
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Chestnut flowers, lemon balm plants and their decoctions were incorporated into "Serra da Estrela" cheese, to assess their potential to preserve its nutritional properties and provide new foodstuffs. The analyses were carried out after the normal ripening period of 1month and after 6months of storage. The most abundant nutrients were proteins and fats. The most abundant minerals were Ca and Na, while C16:0 and C18:1 were the main fatty acids. Saturated fatty acids were the most abundant, followed by the monounsaturated. Moisture seemed to be lower in the samples with the plants incorporated. The dried plants, when incorporated, seemed to be more efficient as preservers then the decoctions, although these better preserved the proteins. These plants can be regarded as promising natural preservers in foodstuffs cheese, given the preservation of key parameters and the slight impact on the nutritional value.
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The production of natural extracts requires suitable processing conditions to maximize the preservation of the bioactive ingredients. Herein, a microwave-assisted extraction (MAE) process was optimized, by means of response surface methodology (RSM), to maximize the recovery of phenolic acids and flavonoids and obtain antioxidant ingredients from tomato. A 5-level full factorial Box-Behnken design was successfully implemented for MAE optimization, in which the processing time (t), temperature (T), ethanol concentration (Et) and solid/liquid ratio (S/L) were relevant independent variables. The proposed model was validated based on the high values of the adjusted coefficient of determination and on the non-significant differences between experimental and predicted values. The global optimum processing conditions (t=20 min; T=180 ºC; Et=0 %; and S/L=45 g/L) provided tomato extracts with high potential as nutraceuticals or as active ingredients in the design of functional foods. Additionally, the round tomato variety was highlighted as a source of added-value phenolic acids and flavonoids.
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The constant need to improve helicopter performance requires the optimization of existing and future rotor designs. A crucial indicator of rotor capability is hover performance, which depends on the near-body flow as well as the structure and strength of the tip vortices formed at the trailing edge of the blades. Computational Fluid Dynamics (CFD) solvers must balance computational expenses with preservation of the flow, and to limit computational expenses the mesh is often coarsened in the outer regions of the computational domain. This can lead to degradation of the vortex structures which compose the rotor wake. The current work conducts three-dimensional simulations using OVERTURNS, a three-dimensional structured grid solver that models the flow field using the Reynolds-Averaged Navier-Stokes equations. The S-76 rotor in hover was chosen as the test case for evaluating the OVERTURNS solver, focusing on methods to better preserve the rotor wake. Using the hover condition, various computational domains, spatial schemes, and boundary conditions were tested. Furthermore, a mesh adaption routine was implemented, allowing for the increased refinement of the mesh in areas of turbulent flow without the need to add points to the mesh. The adapted mesh was employed to conduct a sweep of collective pitch angles, comparing the resolved wake and integrated forces to existing computational and experimental results. The integrated thrust values saw very close agreement across all tested pitch angles, while the power was slightly over predicted, resulting in under prediction of the Figure of Merit. Meanwhile, the tip vortices have been preserved for multiple blade passages, indicating an improvement in vortex preservation when compared with previous work. Finally, further results from a single collective pitch case were presented to provide a more complete picture of the solver results.
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Due to the sensitive nature of patient data, the secondary use of electronic health records (EHR) is restricted in scientific research and product development. Such restrictions pursue to preserve the privacy of respective patients by limiting the availability and variety of sensitive patient data. Current limitations do not correspond with the actual needs requested by the potential secondary users. In this thesis, the secondary use of Finnish and Swedish EHR data is explored for the purpose of enhancing the availability of such data for clinical research and product development. Involved EHR-related procedures and technologies are analysed to identify the issues limiting the secondary use of patient data. Successful secondary use of patient data increases the data value. To explore the identified circumstances, a case study of potential secondary users and use intentions regarding EHR data was carried out in Finland and Sweden. The data collection for the conducted case study was performed using semi-structured interviews. In total, 14 Finnish and Swedish experts representing scientific research, health management, and business were interviewed. The motivation for the corresponding interviews was to evaluate the protection of EHR data used for secondary purposes. The efficiency of implemented procedures and technologies was analysed in terms of data availability and privacy preserving. The results of the conducted case study show that the factors affecting EHR availability are divided to three categories: management of patient data, preservation of patients' privacy, and potential secondary users. Identified issues regarding data management included laborious and inconsistent data request procedures and the role and effect of external service providers. Based on the study findings, two secondary use approaches enabling the secondary use of EHR data are identified: data alteration and protected processing environment. Data alteration increases the availability of relevant EHR data, further decreasing the value of such data. Protected processing approach restricts the amount of potential users and use intentions while providing more valuable data content.
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Dissertação de Mestrado, Ciências Biomédicas, Departamento de Ciências Biomédicas e Medicina, Universidade do Algarve, 2016
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Purpose: To evaluate and compare the performance of Ripplet Type-1 transform and directional discrete cosine transform (DDCT) and their combinations for improved representation of MRI images while preserving its fine features such as edges along the smooth curves and textures. Methods: In a novel image representation method based on fusion of Ripplet type-1 and conventional/directional DCT transforms, source images were enhanced in terms of visual quality using Ripplet and DDCT and their various combinations. The enhancement achieved was quantified on the basis of peak signal to noise ratio (PSNR), mean square error (MSE), structural content (SC), average difference (AD), maximum difference (MD), normalized cross correlation (NCC), and normalized absolute error (NAE). To determine the attributes of both transforms, these transforms were combined to represent the entire image as well. All the possible combinations were tested to present a complete study of combinations of the transforms and the contrasts were evaluated amongst all the combinations. Results: While using the direct combining method (DDCT) first and then the Ripplet method, a PSNR value of 32.3512 was obtained which is comparatively higher than the PSNR values of the other combinations. This novel designed technique gives PSNR value approximately equal to the PSNR’s of parent techniques. Along with this, it was able to preserve edge information, texture information and various other directional image features. The fusion of DDCT followed by the Ripplet reproduced the best images. Conclusion: The transformation of images using Ripplet followed by DDCT ensures a more efficient method for the representation of images with preservation of its fine details like edges and textures.
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Family businesses are special in many respects. By examining their financial characteristics one can come to unique conclusions/results. This paper explores the general characteristics of the financial behaviour of family businesses, presents the main findings of the INSIST project’s company case studies concerning financing issues and strategies, and intends to identify the financial characteristics of company succession. The whole existence of family businesses is characterized by a duality of the family and business dimensions and this remains the case in their financial affairs. The financial decisions in family businesses (especially SMEs) are affected by aspects involving a duality of goals rather than exclusively profitability, the simultaneous presence of family and business financial needs, and the preferential handling of family needs at the expense of business needs (although it has to be said that there is evidence of family investments being postponed for the sake of business, too. Family businesses, beyond their actual effectiveness, are guided by individual goals like securing living standards, ensuring workplaces for family members, stability of operation, preservation of the company’s good reputation, and keeping the company’s size at a level that the immediate family can control and manage. The INSIST project’s company case studies revealed some interesting traits of family business finances like the importance of financial support from the founder’s family during the establishment of the company, the use of bootstrapping techniques, the financial characteristics of succession, and the role of family members in financial management.
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With progressive climate change, the preservation of biodiversity is becoming increasingly important. Only if the gene pool is large enough and requirements of species are diverse, there will be species that can adapt to the changing circumstances. To maintain biodiversity, we must understand the consequences of the various strategies. Mathematical models of population dynamics could provide prognoses. However, a model that would reproduce and explain the mechanisms behind the diversity of species that we observe experimentally and in nature is still needed. A combination of theoretical models with detailed experiments is needed to test biological processes in models and compare predictions with outcomes in reality. In this thesis, several food webs are modeled and analyzed. Among others, models are formulated of laboratory experiments performed in the Zoological Institute of the University of Cologne. Numerical data of the simulations is in good agreement with the real experimental results. Via numerical simulations it can be demonstrated that few assumptions are necessary to reproduce in a model the sustained oscillations of the population size that experiments show. However, analysis indicates that species "thrown together by chance" are not very likely to survive together over long periods. Even larger food nets do not show significantly different outcomes and prove how extraordinary and complicated natural diversity is. In order to produce such a coexistence of randomly selected species—as the experiment does—models require additional information about biological processes or restrictions on the assumptions. Another explanation for the observed coexistence is a slow extinction that takes longer than the observation time. Simulated species survive a comparable period of time before they die out eventually. Interestingly, it can be stated that the same models allow the survival of several species in equilibrium and thus do not follow the so-called competitive exclusion principle. This state of equilibrium is more fragile, however, to changes in nutrient supply than the oscillating coexistence. Overall, the studies show, that having a diverse system means that population numbers are probably oscillating, and on the other hand oscillating population numbers stabilize a food web both against demographic noise as well as against changes of the habitat. Model predictions can certainly not be converted at their face value into policies for real ecosystems. But the stabilizing character of fluctuations should be considered in the regulations of animal populations.
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Background: Intensified selection of polled individuals has recently gained importance in predominantly horned dairy cattle breeds as an alternative to routine dehorning. The status quo of the current polled breeding pool of genetically-closely related artificial insemination sires with lower breeding values for performance traits raises questions regarding the effects of intensified selection based on this founder pool. Methods: We developed a stochastic simulation framework that combines the stochastic simulation software QMSim and a self-designed R program named QUALsim that acts as an external extension. Two traits were simulated in a dairy cattle population for 25 generations: one quantitative (QMSim) and one qualitative trait with Mendelian inheritance (i.e. polledness, QUALsim). The assignment scheme for qualitative trait genotypes initiated realistic initial breeding situations regarding allele frequencies, true breeding values for the quantitative trait and genetic relatedness. Intensified selection for polled cattle was achieved using an approach that weights estimated breeding values in the animal best linear unbiased prediction model for the quantitative trait depending on genotypes or phenotypes for the polled trait with a user-defined weighting factor. Results: Selection response for the polled trait was highest in the selection scheme based on genotypes. Selection based on phenotypes led to significantly lower allele frequencies for polled. The male selection path played a significantly greater role for a fast dissemination of polled alleles compared to female selection strategies. Fixation of the polled allele implies selection based on polled genotypes among males. In comparison to a base breeding scenario that does not take polledness into account, intensive selection for polled substantially reduced genetic gain for this quantitative trait after 25 generations. Reducing selection intensity for polled males while maintaining strong selection intensity among females, simultaneously decreased losses in genetic gain and achieved a final allele frequency of 0.93 for polled. Conclusions: A fast transition to a completely polled population through intensified selection for polled was in contradiction to the preservation of high genetic gain for the quantitative trait. Selection on male polled genotypes with moderate weighting, and selection on female polled phenotypes with high weighting, could be a suitable compromise regarding all important breeding aspects.
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Ribot’s law refers to the better preservation of remote memories compared with recent ones that presumably characterizes retrograde amnesia. Even if Ribot-type temporal gradient has been extensively studied in retrograde amnesia, particularly in Alzheimer’s disease (AD), this pattern has not been consistently found. One explanation for these results may be that rehearsal frequency rather than remoteness accounts for the better preservation of these memories. Thus, the aim of present study was to address this question by studying retrograde semantic memory in subjects with amnestic mild cognitive impairment (aMCI) (n = 20), mild AD (n = 20) and in healthy older controls (HC; n = 19). In order to evaluate the impact of repetition as well as the impact of remoteness, we used a test assessing memory for enduring and transient public events that occurred in the recent and remote past. Results show no clear temporal gradient across time periods (1960–1975; 1976–1990; 1991–2005; 2006–2011), but a better performance was observed in all three groups for enduring compared with transient events. Moreover, although deficits were globally found in both patients groups compared with HC, more specific analyses revealed that aMCI patients were only impaired on transient events while AD patients were impaired on both transient and enduring events. Exploratory analyses also revealed a tendency suggesting preservation of remote transient events in aMCI. These findings are discussed with regards to memory consolidation models.
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The Charter of European Planning 2013 presents a Vision for the future of European cities and regions, highlighting the sustainability of cities and the preservation of urban ecosystems, integrating the man-made environment with the natural ecosystems and contribute to the well-being and quality of life of their inhabitants and other stakeholders. Thus, urban public policies are crucial to the improvement of the landscape ecological system, achievable by city planning and design. The paper aims to analyse if public urban policies in Portugal have been integrating strategies and/or guidelines to enhance the ecological system of the landscape. Then, which new perspectives are possible, framed by the recently approved law Bases of Public Policy of Soils, Land Management and Urban Planning (2014). This new law, in contrast with the previous ones, don’t allow reserving land to urbanize, in municipal master plans. Moreover, it is possible to revert land classified for urban purposes in those plans into rustic soils (when it is not yet infra-structured or built). It allows creating new planning and design dynamics, convert several areas and including them in the urban ecological structure, essential to the enhancement of landscape ecological system. This is a filed of work where landscape architecture has huge responsibilities, by associating and harmonize man-made environment with natural systems, enlightening sustainability consistent with conservation and improvement of Nature while contributing to the well-being and quality of life of Man. A sustainability that is ethical, aesthetic, ecological and cultural. The study is supported by a case study – the city of Évora. The ultimate goal is to propose measures to promote larger and better integration of ecological component in urban public policies, framed by the new territorial management law, taking into account and highlighting the specificities of the landscape system – Man and Nature – at the local level.
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The preservation of modern and contemporary art and costume collections in museums requires a complete understanding of their constituent materials which are often synthetic or semi-synthetic polymers. An extraordinary amount of quality information can be gained from instrumental techniques, but some of them have the disadvantage of being destructive. This paper presents a new totally integrated non-invasive methodology, for the identification of polymers and their additives, on plastic artefacts in museums. NMR (nuclear magnetic resonance) and in-situ FTIR-ATR (attenuated total reflection infrared spectroscopy) combination allowed the full characterization of the structure of thesematerials and correct identification of each one. The NMR technique applied to leached surface exudates identified unequivocally a great number of additives, exceeding the Py–GC–MS analysis of micro-fragments in number and efficiency. Additionally, in-situ FTIR-ATR provided exactly the same information of the destructive μ-FTIR about the polymer structure and confirmed the presence of some additives. Eight costume pieces (cosmetic boxes and purses), dating to the beginning of the 20th century and belonging to the Portuguese National Museum of Costume and Fashion, were correctly identified with this new integrated methodology, as beingmade of plastics derived fromcellulose acetate or cellulose nitrate polymers, contradicting the initial information that these pieces were made of Bakelite. The identification of a surprisingly large number of different additives forms an added value of this methodology and opens a perspective of a quick and better characterization of plastic artefacts in museum environments.
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This essay addresses the application of indigenous plants in Landscape Architecture projects, based on studies carried out in the field of phytosociology and sinphytosociology. Through this knowledge, it is possible to increase and improve the use of indigenous plants in Projects, aiming at the preservation of biodiversity. Thus, to better understand the western Mediterranean territory, we present a brief biophysical characterization, in which we point out the main factors which contribute to the ground coverage’s distribution in the landscape, namely, concerning climate (oceanity, ombroclimate and thermoclimate) and substrate (geology and lithology). In view of the high level of uniqueness of the identified conditions, a synthesis of the potential main existing climatophilous woods is carried out, regarding sinphytosocialogical class/order, furthermore, pointing out, the main serial stages, their vegetation bioindicators and the ecological peculiarities of each stage (regressive or progressive). Therefore, based on the study area, we point out the vegetation bioindicator’s value as a work tool during analysis, thus allowing us to understand the existing edaphoclimatic conditions, as well as to elaborate a quick diagnosis of each potential climatophilous vegetation series. Moreover, based on the main stages of substitution, it is also possible to identify the presence of endemic plants, or under protection status, and finally, the conservation state of the study area. Further ahead, in project proposal phase, based on information gathered previously, we point out the possibility of elaborating a list of plants correctly adapted to the existing mesologicall conditions. Thus, within each serial stage, the necessary ecological conditions for a correct adaption of the vegetation material are referred, therefore, avoiding possible limiting factors to their development, such as precipitation, soil erosion, light availability, salinity, among many others. Lastly, some considerations are made about the main ideas that should be remembered throughout this essay, namely, regarding the importance of the use of sinphytosociology’s knowledge as an analysis tool, as well as of high interest for the elaboration of proposals which aim at the floristic heritage’s conservation and the landscape’s scenic quality. Ce travail traite de l`application de plantes autochtones dans des projets d`Architecture Paysagiste ayant pour base des études réalisées dans le cadre de la phytosociologie et Symphytosociologie. À travers ces connaissances, il est possible d`incrémenter et améliorer l`utilisation de plantes autochtones dans les Projets basés sur la conservation de la biodiversité. Ainsi, afin de mieux comprendre le territorie de la méditérrannée occidentale, on présente une brève caractérisation biophysique, dans laquelle nous soulignons les principaux facteurs qui contribuent à la répartition de la végétation dans le paysage, notamment au niveau climatique (l`océanité, ombrothermique et thermoclimatique) et du substrat (géologie et lithologie). Face aux conditions, identifiées ci-dessus, élévées en originalité, il est utile d`élaborer une synthèse des principaux bois potentiels climatophiles existants au niveau de la classe/ordre symphitosociologique, en soulignant également les principales étapes de série, leurs bioindicateurs végétaux et aux particularités écologiques de chaque étape (régressive ou progressive). Ainsi, sur la base de l`interprétation de la zone d`étude, le bioindicateur végétal se distingue comme un outil de travail durant l`analyse, permettant de cette façon comprendre les conditions édapho-climatiques existantes, ainsi comme élaborer un rapide diagnostic de chaque série de végétation potentielle climatophile. En outre, sur la base des principales étapes de remplacement, il est également possible d`identifier la présence de plantes endémiques, ou avec un statut de protection et enfin l`état de conservation de la zone d`étude. Déjà au stade de proposition du projet, basée sur l`information recueillie précédemment, il y a la possibilité d`établir une liste de plantes bien adaptées aux conditions mésologiques. Ainsi, dans chaque étape de série, les conditions écologiques nécessaires à une bonne adaptation de la matière végétale sont référées, évitant ainsi des facteurs limitant à son développement, tels que les précipitations, l`érosion des soís, disponibilité de la lumière, de la salinité, parmi beaucoup d`autres. Et enfin, quelques considérations se tissent sur les principales idées à retenir tout au long du travail, notamment l`importance d`utiliser la connaissance de la symphytosociologie comme un outil d`analyse d`un grand intérêt pour la développement de propositions pour la conservation du patrimoine floristique et la qualité pittoresque du paysage.
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Nowadays, World Heritage Sites (WHS) have been facing new challenges, partially due to a different tourism consumption patterns. As it is highlighted in a considerable amount of studies, visits to these sites are almost justified by this prestigious classification and motivations are closely associated with their cultural aspects and quality of the overall environment (among others, Marujo et al, 2012). However, a diversity of tourists’ profiles have been underlined in the literature. Starting from the results obtained in a previous study about cultural tourists’ profile, conducted during the year 2009 in the city of Évora, Portugal, it is our intend to compare the results with a recent survey applied to the visitors of the same city. Recognition of Évora by UNESCO in 1986 as “World Heritage” has fostered not only the preservation of heritage but also the tourist promotion of the town. This study compares and examined tourists’ profile, regarding from the tourists’ expenditure patterns in Évora. A total of 450 surveys were distributed in 2009, and recently, in 2015, the same numbers of surveys were collected. Chi-squared Automatic Interaction Detection (CHAID) was applied to model consumer patterns of domestic and international visitors, based on socio demographic, trip characteristics, length of stay and the degree of satisfaction of pull factors. CHAID allowed find a population classification in groups that able to describe the dependent variable, average daily tourist expenditure. Results revealed different patterns of daily average expenditure amongst the years, 2009 and 2015, even if primarily results not revealed significant variations in socio-demographic and trip characteristics among the visitors’ core profile. Local authorities should be aware of this changing expensive behavior of cultural visitors and should formulate strategies accordingly. Policy and managerial recommendations are discussed.