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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
401

Hidroaliumosilikato įtaka maisto medžiagų pasisavinamumui skirtingos lyties šunų organizme bei sveikatos būklei / Influence of hydroaluminosilicate on nutrient absorption for male and female dogs and their health

Matonytė, Birutė 05 March 2014 (has links)
Darbo apimtis ir struktūra Darbas parašytas lietuvių kalba, kurį sudaro: įvadas, literatūros apžvalga, medžiagos ir metodai, rezultatai, išvados, naudotos literatūros sąrašas; darbo apimtis 65 puslapiai, darbe yra: 78 literatūros šaltiniai, 15 lentelių ir 13 paveikslėlių. Darbo tikslas įvertinti klinoptilolito įtaką skirtingo amžiaus ir lyties šuniukų augimo spartai ir sveikatingumui. Darbo uždaviniai:  įvertinti šuniukų ir suaugusių šunų šėrimui vartojamų ėdalų maistinę ir energinę vertę;  nustatyti ėdalų suvartojimo kiekius atskirais auginimo periodais priklausomai nuo gyvūno lyties;  nustatyti šuniukų ir suaugusių šunų svorio kitimą priklausomai nuo gyvūno lyties atskirais auginimo periodais;  paskaičiuoti gyvūnų kūno masės priaugimą atskirais auginimo periodais;  nustatyti pagrindinių maisto medžiagų kiekius patinėlių ir kalyčių išmatose;  paskaičiuoti maisto medžiagų pasisavinamumo lygį šuniukų ir suaugusių šunų organizme;  pateikti stebėjimo rezultatus apie išskiriamų išmatų konsistenciją;  pateikti šunų išmatų bakteriologinio tyrimo rezultatus;  pateikti išmatų pH dydžius atskirais auginimo tarpsniais. Šuniukų ir šunų šėrimui buvo naudojamas visavertis ėdalas „NATURE’S PROTECTION“, kurio sudėtyje nustatyta 920 g kg-1 sausosios medžiagos, 260 g kg-1 žalių baltymų, 150 g kg-1 žalių riebalų, 52 g kg-1 žalių pelenų, energinė vertė 20,25 MJ kg-1. Nustatyta, kad tiriamosios grupės šunys ir kalytės tiriamojo laikotarpio atskirais mėnesiais suvartojo mažesnius... [toliau žr. visą tekstą] / The scope of work and structure The Master's project is written in Lithuanian and consists of introduction, literature review, materials and methods, results, conclusions, references. The project comprises of 65 pages, 78 references, 15 tables and 13 pictures. Project aims: the main aim of this project is to evaluate the impact of a clinoptilolite of different age puppies growth rate and their health status. Objectives of the project:  to evaluate the puppies and dogs feeds nutritional and energy values  to determine the amount of food consumptions of different gender animals of various growth periods  to measure the weight alteration of different gender puppies and adult dogs of various growth periods  to estimate the animals weight gain of various growth periods  to measure the amount of the basic nutrients in male and female dogs faeces  to calculate the nutrients absorption level of puppies and adult dogs organisms  to represent the observation results about the dogs faeces consistency  to introduce the results of a bacteriological analysis of the dogs feaces  to present the dogs feaces values of pH of various growth periods Dogs and puppies have been fed with a full-rate dog‘s fodder “NATURE’S PROTECTION“, containing 920 g kg-1 of dry substance, 260 g kg-1 of raw protein, 150 g kg-1 of raw fats, 52 g kg-1 of raw ash; its energetic value - 20,25 MJ kg-1. As research data reveal, female and male dogs of a test group have been consuming lower amount of full-rate... [to full text]
402

Parametrization of relative humidity- and wavelength-dependent optical properties of mixed Saharan dust and marine aerosol

Schladitz, Alexander 01 July 2011 (has links) (PDF)
Aerosol particles interact with sunlight through scattering and absorption and have therefore a direct radiative effect. Hygroscopic aerosol particles take up water and are able to grow in size below 100% relative humidity, which involves the change of optical properties and the direct radiative effect. The change of aerosol optical properties for aerosol mixtures under humidification is presently not well understood, especially for the largest particle sources worldwide. The present PhD-thesis quantifies wavelength- and humidity-dependent aerosol optical properties for a mixture of Saharan mineral dust and marine aerosol. For quantification, an aerosol model was developed, which based on in-situ measurements of microphysical and optical properties at Cape Verde. With this model, aerosol optical properties were calculated from the dry state up to 90% relative humidity. To validate the model, a measure of the total extenuated light from particles under ambient conditions was used. Finally, the humidity dependence of aerosol optical properties for marine aerosol, Saharan dust aerosol, and a mixture of both species was described by two empirical equations. With the wavelength of the incident visible solar radiation, relative humidity, and dry dust volume fraction, the humidity dependence of optical properties can be calculated from tabulated values. To calculate radiative effects, aerosol optical properties were used as input parameters for global circulation models including radiative transfer. Due to the complexity of aerosol related processes, they have been treated implicitly, meaning in parameterized form. For modelling purposes, the present PhD-thesis provides a solution to include humidity effects of aerosol optical properties. / Aerosolpartikel wechselwirken durch Streu- und Absorptionsprozesse mit der einfallenden Sonnenstrahlung und haben somit einen direkten Strahlungseffekt. Bei relativen Feuchten bis 100% können Aerosolpartikel aufquellen und somit ihre Größe ändern. Im Zuge des Aufquellens, ändern sich die optischen Eigenschaften und somit auch der direkte Strahlungseffekt der Aerosolpartikel. Speziell für Mischungen von verschiedenen Aerosolspezies ist die Änderung der optischen Eigenschaften des Aerosols durch Feuchte Einfuss noch nicht ausreichend verstanden. Gegenstand der vorliegenden Arbeit ist daher die Quantifizierung der wellenlängen- und feuchteabhängigen optischen Eigenschaften einer Mischung von Saharastaub- und marinen Aerosol. Die zur Quantifizierung notwendigen Daten wurden im Rahmen einer Feldmessung von mikrophysikalischen- und optischen Aerosol-Eigenschaften auf den Kapverdischen Inseln gesammelt. Auf Grundlage dieser Messungen wurde ein Aerosol-Modell entwickelt. Dieses Modell wurde daraufhin verwendet, um Berechnungen von optischen Aerosol-Eigenschaften bei relativen Feuchten bis 90% durchzuführen. Eine Messung der Lichtschwächung durch Aerosolpartikel unter Umgebungsbedingungen wurde verwandt, um das Modell bei Umgebungsfeuchten zu validieren. Die Wellenlängen- und Feuchteabhängigkeit der optischen Eigenschaften des Aerosols wurde parametrisiert und konnte anhand von zwei Parametergleichungen bestimmt werden. Unter Benutzung von tabellierten Werten und der Wellenlänge des einfallenden sichtbaren Sonnenlichtes, der relativen Feuchte, sowie der Staubvolumenfraktion, kann die Feuchteabhängigkeit von wichtigen Aerosol-optischen Eigenschaften für Saharastaub, marinen Aerosol und einer Mischung aus beiden Komponenten bestimmt werden. Globale Zirkulationsmodelle, die auch eine Berechnung von Strahlungseffekten durch Aerosolpartikel beinhalten, nutzen Aerosol-optische Eigenschaften als Eingabeparameter. Durch zunehmende Komplexitiät zur Beschreibung von Wechselwirkungen in der Atmosphäre, sind einfache Parametrisierungen unabdingbar. Die vorliegende Arbeit liefert daher einen wichtigen Beitrag für die Modellierung von Strahlungseffekten durch Aerosolpartikel und somit zum Verständnis des Strahlungshaushaltes der Erde.
403

Διαχείριση και έλεγχος Programmable Logic Controller (PLC) μέσω Ethernet/Internet

Χριστόπουλος, Κωνσταντίνος 20 September 2010 (has links)
Ο στόχος της παρούσας διπλωματικής εργασίας είναι ο έλεγχος και αποκατάσταση της θερμοκρασίας και της υγρασίας από απόσταση σε ένα χώρο ο οποίος απαιτεί συγκεκριμένες τιμές των δύο παραπάνω μεγεθών. Ένας τέτοιος χώρος μπορεί να είναι μια αίθουσα χειρουργείου ή μια μονάδα εντατικής θεραπείας. Ανάλογα με τις επιθυμητές θερμοκρασίες που έχουν τεθεί, ενεργοποιούνται οι βάνες του θερμαντικού ή του ψυκτικού στοιχείου. Όταν η υγρασία του χώρου είναι κατώτερη της επιθυμητής, ενεργοποιείται η τρίοδος βάνα ατμού. Όταν η υγρασία του χώρου είναι υψηλότερη της επιθυμητής ενεργοποιείται η τρίοδος βάνα του ψυκτικού στοιχείου για επιπλέον ψύξη (αφύγρανση) και παράλληλα, αν χρειαστεί ενεργοποιεί και την τρίοδο βάνα του θερμαντικού στοιχείου για να διατηρήσει τη θερμοκρασία του χώρου στα επιθυμητά επίπεδα. Όλα αυτά υλοποιούνται με τη βοήθεια του PLC S7 300 όσο αφορά το λειτουργικό μέρος, της μονάδας CP 343-1 Lean για την επικοινωνία της εγκατάστασης από απόσταση μέσω ethernet, το LabVIEW 9.0 για την υλοποίηση του SCADA(Supervisory Control and Data Acquisition) και τέλος ο OPC SERVER της National instrument για την επικοινωνία του PLC S7 300 με το LabVIEW 9.0. / The scope of this thesis is the control and restoration of temperature and humidity from distance in environments which demand precise values of these two measurements. Such an environment can be an Operating Room or an Intensive Care Unit. The valves of the heating or the cooling element are activated according to the desired temperature. When room humidity is below the desired one, the dew three-port valve is activated. On the other hand when humidity is above the desired level the three-port valve of the cooling element is activated for further cooling (dehydration) and at the same time, if needed, it activates the three-port valve of the heating element to maintain the room temperature at the desired level. This is possible with the use of PLC S7 300, when it comes to the functional part, the CP 343-1 Lean unit for the distant communication of the installation through the use of Ethernet, the LabVIEW 9.0 for the implementation of the SCADA(Supervisory Control and Data Acquisition) and the OPC SERVER of the National Instrument for the communication of the PLC S7 300 with LabVIEW 9.0.
404

Μελέτη της επίδρασης των φυσικοχημικών παραμέτρων ανάπτυξης της μυκοτοξίνης Ζεαραλενόνης (ΖΟΝ) σε δημητριακά

Αποστολόπουλος, Νεκτάριος 12 January 2012 (has links)
Το πρόβλημα με τις μυκοτοξίνες είναι σημαντικό και δικαιολογημένα προκαλεί ανησυχίες. Αναφέρεται ως παγκόσμιος κίνδυνος και θεωρείται ως μία από τις πλέον σοβαρές προκλήσεις για την ασφάλεια των τροφίμων, την υγεία των ανθρώπων, των ζώων, και για τη σύγχρονη τοξικολογία. Με τον «όρο» μυκοτοξίνες εννοούμε τοξίνες οι οποίες παράγονται από μύκητες. Συγκεκριμένα πρόκειται για προϊόντα δευτερογενούς μεταβολισμού των μυκήτων (Aspergillus spp Fusarium spp, Penicillium spp, κ.α). Υπάρχει μία πληθώρα από διάφορες μυκοτοξίνες οι οποίες απαντώνται σε πολλές τροφές, όπως στο γάλα, στα δημητριακά, στους ξηρούς καρπούς, στα αποξηραμένα φρούτα, στο αλεύρι κ.α. που καταναλώνουν καθημερινά οι άνθρωποι, αλλά και σε ζωικές τροφές. ωστόσο μόνο για κάποιες από αυτές υπάρχουν τεκμηριωμένες μελέτες ενώ ακόμα λιγότερες είναι αυτές, για τις οποίες έχουν προσδιοριστεί τα νόμιμα επιτρεπτά όρια συγκέντρωσης στις τροφές, που καταναλώνονται καθημερινά. Οι μυκοτοξίνες θεωρούνται γενικά επικίνδυνες ενώσεις που παράγονται από ορισμένα είδη μυκήτων, οι οποίοι αναπτύσσονται σε προϊόντα αγροτικών καλλιεργειών είτε πριν τη συγκομιδή, είτε κατά την αποθήκευσή τους σε γεωργικές εγκαταστάσεις και παραμένουν δραστικές για μεγάλο χρονικό διάστημα και μετά την καταστροφή των μυκήτων από τους οποίους προήλθαν. Η εμφάνισή τους στα τρόφιμα και στα ποτά έχει αναγνωριστεί ως απειλή για την υγεία τόσο του ανθρώπου όσο και των ζώων, είτε αυτή προέρχεται από την άμεση μόλυνση των φυτικών ιστών, είτε από προϊόντα που έχουν παραχθεί από αυτά, είτε από την μεταφορά των μυκοτοξινών και των μεταβολιτών τους στους ζωικούς ιστούς, και κατά συνέπεια στο γάλα, στα αυγά και αλλού. Μερικές από αυτές τις μυκοτοξίνες, όπως για παράδειγμα οι αφλατοξίνες, παρουσιάζουν εξαιρετικά υψηλή τοξικότητα, γεγονός που τις καθιστά ενώσεις που χρήζουν ιδιαίτερη προσοχή. ως εκ τούτου κρίνεται απαραίτητο όλα τα αγροτικά προϊόντα που προορίζονται για τον άνθρωπο ή για ζωοτροφές να υποβάλλονται σε συνεχή και σχολαστικό έλεγχο. Αντικείμενο μελέτης της παρούσας εργασίας είναι να μελετήσει τις παραμέτρους (θερμοκρασία και υγρασία) οι οποίοι επηρεάζουν την ανάπτυξη της μυκοτοξίνης ζεαραλενόνης χρησιμοποιώντας ως υπόστρωμα αλεύρι από αποθηκευμένο αραβόσιτο. Στόχος ήταν ο έλεγχος των συνθηκών καλλιέργειας, αποθήκευσης και συντήρησης των πρωτογενών γεωργικών προϊόντων έτσι ώστε να ελαττώνεται η ανάπτυξη μυκοτοξινών στα γεωργικά προϊόντα και στα τρόφιμα. Η δραστηριότητα βοήθησε στη διερεύνηση του μηχανισμού δράσης των συνθηκών που οδηγούν στην ανάπτυξη μυκοτοξινών τόσο κατά την αποθήκευση της πρώτης ύλης, όσο και κατά τα στάδια επεξεργασίας, παραγωγής και τυποποίησης του τελικού προϊόντος. / The problem with mycotoxins is a significant and legitimate concern. Referred to as global risk and is considered one of the most serious challenges to food security, human health, animals, and modern toxicology. With the "average" mean toxins mycotoxins produced by fungi. It is a secondary metabolic products of fungi (Aspergillus spp Fusarium spp, Penicillium spp, etc.). There is a plethora of different mycotoxins found in many foods such as milk, cereals, nuts, dried fruits, flour, etc. consumed daily by people, but also in animal feeds. But only some of them are documented studies and even fewer are those, which have been identified, legally permissible concentration limits in foods consumed daily. The mycotoxins are generally considered harmful compounds produced by certain species of fungi which grow on agricultural products or crops before harvest or during storage in agricultural systems and remain active for a long time after the destruction of fungi of which came. Their occurrence in foods and beverages has been recognized as a health threat to both human and animal, whether it comes from direct infection of plant tissues or products derived there from, or the transfer of mycotoxins and their metabolites in animal tissues, and hence in milk, eggs and elsewhere. Some of these mycotoxins such as aflatoxins, are extremely high toxicity, which makes compounds that deserve particular attention. Therefore it is essential that all agricultural products intended for human or animal feed can be subjected to constant and meticulous. The subject of this paper is to study the parameters (temperature and humidity) that influence the development of the mycotoxin zearalenone using as substrate flour stored maize. The aim was to check the growing conditions, storage and maintenance of primary agricultural products and thus reduce the development of mycotoxins in agricultural products and foodstuffs. The activity helped to investigate the mechanism of action of the conditions that lead to the development of both mycotoxins during storage of raw materials and in processing, production and packaging of finished product.
405

Développement de couches de diffusion de piles PEMFC pour un fonctionnement à faible humidité relative / Development of PEMFCs Gas Diffusion Layers operating at low relative humidity

Jonquille, Jenny 21 April 2011 (has links)
Afin de favoriser la commercialisation à grande échelle des piles à combustible PEMFC, de nombreuses études sont menées dans le but de réduire les coûts et d'augmenter la durée de vie tout en améliorant les performances et de comprendre les phénomènes physiques mis en jeu. Cette étude se concentre sur le développement de couches de diffusion pour un fonctionnement à faible humidité relative, en particulier sur l'influence de la structure du support de diffusion sur les performances. Grâce à un procédé de fabrication différent de ceux utilisés pour les produits actuellement commercialisés, la structure des supports est plus aisément modifiée. Ainsi, selon les paramètres de fabrication choisis, les propriétés physico-chimiques associées donnent accès à des niveaux de performances différents. Le modèle d'analyse mis en place permet d'expliquer ces différences observées. Par conséquent, il permet de relier les paramètres de fabrication aux propriétés physiques et aux performances en pile. / To help PEMFC development and large scale commercialization, several studies deal with reducing costs and increasing durability while trying to improve performances and to understand physical phenomena involved. This study focuses on developing gas diffusion media which operates at low relative humidity, more particularly it deals with the influence of the structure of gas diffusion media on performances. Thanks to a process different from those used for currently commercialized gas diffusion layers, the structure of the media is more easily modified. According to the manufacturing parameters chosen, different physical and chemical properties will be obtained and thus different performances. A model is used to help analyze these differences and consequently allow the link between manufacturing parameters and physical properties and performances.
406

Aspectos termodinâmicos de um vórtice ciclônico de altos níveis sobre o Nordeste do Brasil.

FERREIRA, Rosaria Rodrigues. 14 August 2018 (has links)
Submitted by Lucienne Costa (lucienneferreira@ufcg.edu.br) on 2018-08-14T20:28:08Z No. of bitstreams: 1 ROSARIA RODRIGUES FERREIRA – DISSERTAÇÃO (PPGMET) 2017.pdf: 5493897 bytes, checksum: c1fcaad15dec53c48dd9576c47d0d0f2 (MD5) / Made available in DSpace on 2018-08-14T20:28:08Z (GMT). No. of bitstreams: 1 ROSARIA RODRIGUES FERREIRA – DISSERTAÇÃO (PPGMET) 2017.pdf: 5493897 bytes, checksum: c1fcaad15dec53c48dd9576c47d0d0f2 (MD5) Previous issue date: 2017-02-24 / Capes / Os balanços de calor e umidade são comumente utilizados no estudo do comportamento atmosférico na presença de forçamento térmicos e dinâmicos. Em 1973, alguns autores introduziram um método para o cálculo do que chamaram de fonte aparente de calor (Q1) e sumidouro aparente de umidade (Q2), obtidos como resíduos dos balanços de calor e umidade em grande escala. Com este trabalho pretende-se investigar as características dos balanços de umidade e calor para a região de atuação de um vórtice ciclônico de altos níveis (VCAN) sobre a região nordeste do Brasil (NEB), para um evento ocorrido durante o período de 13 a 24 de janeiro de 2011. A análise do ciclo de vida relacionada ao VCAN em termos do balanço de umidade e calor configura-se de grande relevância, já que as mudanças de fase da água são importantes fontes ou sumidouros de energia na atmosfera tropical, em que a condensação da grande quantidade de vapor d’água leva à liberação de grande quantidade de energia, na forma de calor latente de condensação. Os conjuntos de dados utilizados neste estudo foram de reanálises do ERA-Interim pertencentes ao European Centre for Medium-Range Weather Forecasts (ECMWF) com uma resolução espacial de 0.5ᵒx0.5ᵒ, juntamente com o uso de imagens de satélite GOES-12 do canal infravermelho realçado pertencente ao banco de imagens da Divisão de Satélites Ambientais (DSA/INPE), informações de radiossondagem atmosféricas, dados de precipitação estimada pelo satélite Tropical Rainfall Measuring Mission (TRMM), e ainda dados de estação meteorológica de superfície do Instituto Nacional de Meteorologia (INMET). A justificativa que resultou na escolha deste caso de VCAN levou em consideração o fato deste evento ter sido bastante intenso durante seu tempo vida, e teve características bem significantes nas áreas em que o seu centro e sua periferia atuaram. Foram definidos pontos de análises de Q1 e Q2, esses pontos foram ditos como regiões onde o centro e a borda do vórtice estiveram atuando durante seu ciclo de vida. Como resultado foi observado que sobre o ponto da borda, houve uma evolução temporal de Q1 e Q2 desde o nível de 1000 até 200 hPa, durante o período de atuação do vórtice sobre Bom Jesus da Lapa, esses parâmetros mostraram que devido ao centro do VCAN atuar com mais intensidade sobre o local, a subsidência foi dominante, principalmente nos dias em que esse sistema esteve mais intenso. Os picos de Q1 por volta de 400 hPa são indicativos de que o ar frio que advém do centro do VCAN, pode inibir o processo de convecção, e os picos de Q2 por volta de 700 hPa podem estar associados a uma convecção rasa. Já para a cidade de Natal foi visto que durante a atuação da borda do VCAN, Q1 e Q2 se mostraram bem correlacionados, sendo isto um indicativo que o processo de formação de convecção profunda e a liberação de calor latente estiveram acontecendo. / A Heat and moisture balance are commonly used in the study of atmospheric behavior in the presence of thermal and dynamic forcing. In 1973, some authors introduced a method for calculating what they called apparent heat source (Q1) and apparent moisture sink (Q2), obtained as a residual of large-scale heat and moisture balance. This work intends to investigate the characteristics of moisture and heat balance for the performance of a cyclonic vortex of upper levels (VCAN) in northeastern Brazil (NEB) that occurred during the period from 13 to 24 January 2011. The life cycle analysis of VCAN in terms of moisture and heat balance is of major importance, since the phase changes of water are important sources or sinks of energy for the tropical atmosphere, in which large amounts of condensation water vapour leads to release of large amount of energy, in the form of latent heat of condensation. The data set used in this study are of the ERA-Interim reanalysis of the European Centre for MediumRange Weather Forecasts (ECMWF) with a spatial resolution of 0.5°, along with the use of GOES-12 infrared-channel satellite imagery from the Division of Environmental Satellites (DSA/INPE), atmospheric apparatus information, estimated precipitation data the satellite Rainfall Tropical Measuring Mission (TRMM) , and weather station data of the surface of the National Institute of meteorology (INMET). The justification that resulted in the choice of this case VCAN took into account the fact this event was very intense during his time, life and it had very significant characteristics in the areas in which the center and its periphery acted. Points were defined analyses of Q1 and Q2, these points were defined as regions where the center and the edges of the vortex were acting during their life cycle. As a result it was observed that at the border point, there was a temporal evolution of Q1 and Q2 since the 1000 level up to 200 hPa, during the period of operation of the vortex at Bom Jesus da Lapa these parameters showed that due to the center of the VCAN act with more intensity about this site, the subsidence was dominant, especially in the days when this system was more intense, the negative peaks of Q1 around 400 hPa are indicative that the cold air comes from the center of the VCAN may inhibit the process of convection, and the peaks of Q2 around 700 hPa can be associated with shallow convection. For the city of Natal it was seen during the performance of the VCAN, Q1 and Q2 were well correlated, being this an indication that the process of formation of deep convection and the latent heat release were occuring.
407

Influência da umidade e temperatura intrabucais na resistência de união de sistemas adesivos convencionais de dois passos à dentina : estudo in situ.

Saraiva, Letícia Oliveira January 2008 (has links)
Submitted by Suelen Reis (suziy.ellen@gmail.com) on 2013-04-23T18:30:00Z No. of bitstreams: 2 Dissertacao Leticia Saraiva2.pdf: 1296302 bytes, checksum: 1e07502c1e338a38db482de4808d32f7 (MD5) Dissertacao Leticia Saraiva1.pdf: 179952 bytes, checksum: cf1d7c8753ea10452ef96eb6607fddad (MD5) / Approved for entry into archive by Rodrigo Meirelles(rodrigomei@ufba.br) on 2013-05-16T18:04:08Z (GMT) No. of bitstreams: 2 Dissertacao Leticia Saraiva2.pdf: 1296302 bytes, checksum: 1e07502c1e338a38db482de4808d32f7 (MD5) Dissertacao Leticia Saraiva1.pdf: 179952 bytes, checksum: cf1d7c8753ea10452ef96eb6607fddad (MD5) / Made available in DSpace on 2013-05-16T18:04:08Z (GMT). No. of bitstreams: 2 Dissertacao Leticia Saraiva2.pdf: 1296302 bytes, checksum: 1e07502c1e338a38db482de4808d32f7 (MD5) Dissertacao Leticia Saraiva1.pdf: 179952 bytes, checksum: cf1d7c8753ea10452ef96eb6607fddad (MD5) Previous issue date: 2008 / O presente estudo teve como objetivos avaliar o efeito das condições de temperatura e umidade relativa intrabucais na resistência de união à dentina de dois sistemas adesivos convencionais de dois passos (Single Bond 2/SB2 e One Step Plus/OSP), e avaliar a umidade e a temperatura presentes nas regiões de incisivos e molares superiores. Sessenta fragmentos dentários foram esterilizados, fixados em moldeiras de acetato individualizadas, e posicionados in situ em um voluntário para serem restaurados com resina composta, sendo aleatoriamente divididos em seis grupos, de acordo com o sistema adesivo e com a condição de temperatura e umidade: G1 – SB2 na condição ambiental de um consultório odontológico; G2 – SB2 na condição da região de incisivos; G3 – SB2 na condição da região de molares; G4 – OSP na condição ambiental de um consultório odontológico; G5 – OSP na condição da região de incisivos e G6 – OSP na condição da região de molares. Em todas as condições, foram obtidas e registradas a temperatura e a umidade relativa do ar no momento e no local em que as restaurações foram produzidas, usando um termo-higrômetro digital. Após ensaio de microtração, os dados do teste de resistência de união foram submetidos à análise estatística (ANOVA - 2 fatores/ Teste de Tukey, α=5%) e os valores médios em MPa foram: G1 = 20,2 (7,6); G2 = 23,0 (6,5); G3 = 22,7 (6,0); G4 = 29,0 (5,8); G5 = 29,7 (4,9) e G6 = 27,7 (4,8). Os resultados demonstraram que os grupos que utilizaram o OSP (G4, G5 e G6) apresentaram médias semelhantes entre si (p=0,67) e maiores do que os grupos que utilizaram o SB2 (G1, G2 e G3) (p=0,001), também semelhantes entre si (p=0,67). Foi observado que as condições de temperatura presentes nas regiões intrabucais (incisivos e molares) foram semelhantes entre si, e maiores que a condição ambiental do consultório odontológico. A condição de umidade na região de molares foi superior à condição na região de incisivos, e esta foi maior do que a condição presente no ambiente do consultório odontológico. As condições de temperatura e umidade intrabucais não influenciaram a resistência de união dos sistemas adesivos simplificados à dentina. O sistema adesivo One Step Plus apresentou melhores resultados que o sistema Single Bond 2, independentemente das condições de umidade e temperatura. / Salvador
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Estresse térmico em cabras Saanen nos períodos seco e chuvoso criadas em clima tropical quente e úmido no Estado do Ceará / Heat stress in Goats Saanen during the dry created in rainy weather and tropical hot and humid in Ceará

Souza, Priscila Teixeira de January 2010 (has links)
SOUZA, Priscila Teixeira de. Estresse térmico em cabras Saanen nos períodos seco e chuvoso criadas em clima tropical quente e úmido no Estado do Ceará. 60 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Zootecnia, Programa de Pós-Graduação em Zootecnia, Fortaleza-CE, 2010. / Submitted by demia Maia (demiamlm@gmail.com) on 2016-08-12T13:50:24Z No. of bitstreams: 1 2010_dis_ptsouza.pdf: 460141 bytes, checksum: b2cd1ae6cbd7dde232cde4d6345e51a6 (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-08-12T13:52:02Z (GMT) No. of bitstreams: 1 2010_dis_ptsouza.pdf: 460141 bytes, checksum: b2cd1ae6cbd7dde232cde4d6345e51a6 (MD5) / Made available in DSpace on 2016-08-12T13:52:02Z (GMT). No. of bitstreams: 1 2010_dis_ptsouza.pdf: 460141 bytes, checksum: b2cd1ae6cbd7dde232cde4d6345e51a6 (MD5) Previous issue date: 2010 / This study aimed to evaluate the existence of heat stress in Saanen goats during the dry season and rainy in a hot humid tropical climate in the state of Ceara. For this, we assessed the climatic factors, air temperature (TA) and relative humidity (RH) inside and outside the shed, from 8 to 16 h, used to calculate the index of temperature and humidity (ITU) and as the monitoring of physiological parameters (rectal temperature, surface temperature, respiratory rate and heart rate) of 15 lactating goats twice a week, in the morning (9:00 am) and afternoon (14:00 h). The coefficient of adaptability (CA) was estimated by the test Benezra. The data were submitted to analysis of variance at 5% probability. Correlations between environmental variables and physiological parameters were performed using the method of Pearson (P <0.01). The results showed that the highest values of temperature inside and outside the shed, were recorded during the dry season, when the maximum temperatures (TAmax) and minimum (TAmin) was more out of the shed (FG) that in the shed (DG). In the rainy season, only significant difference at 12 h for TAmax (FG - 30.4 º C; DG - 28.5 º C) and 13 h for TAmin (FG - 29.3; DG - 28.2 º C). For relative humidity (RH) showed a statistical difference (P <0.05) at all times between the periods as the URAmax and URAmin inside and outside the shed, and values are always higher in the rainy season. The ITUmax was higher outside the shed at all times during the dry season, whereas in the rainy season only between 9 and 14 hours. Comparing the periods, ITUmax was higher in the rainy season, significant difference (P <0.05) in the shed between 9 and 12 and out of the shed between 9 and 11. For the average ITUmin, the highest values were also observed in the rainy season. All physiological parameters were higher in the afternoon and in the dry season, except for rectal temperature (RT) which was higher in the rainy season. The ITU estimated at the time of collection of physiological parameters was also higher in the afternoon, but between periods, was higher in the rainy season. The TA and the ITU had the best correlation with rectal temperature (r = 0.501 and r = 0.503, P <0.01) and FR (r = 0.642 and r = 0.578, P <0.01) in the rainy season and the surface temperature (TS) and the udder (TSU) with TA in the dry season (TS - r = 0.873 and TSU - r = 0.840), showing that temperature alone is the environmental factor with greatest impact on animal welfare. All correlations of environmental variables and the heart rate were low. The CA among the goats ranged from 4.5 to 6.0 in the dry season to 4.0 / 5.0 out rainy, and those well above the standard coefficient of adaptability, which equals 2.0. Environmental conditions of this study concluded that regardless of the period of the year, Saanen goats are exposed to a hostile environment, and the rainy season is the propitious period to cause heat stress, with higher rates of UTI and consequently high rectal temperature / Este trabalho teve o objetivo de avaliar a existência de estresse térmico em cabras Saanen, nos períodos seco e chuvoso, criadas em clima tropical quente e úmido no estado do Ceará. Para tanto, foram avaliados os elementos climáticos, temperatura do ar (TA) e umidade relativa do ar (URA), dentro e fora do galpão, das 8 às 16 h, utilizados no cálculo do índice de temperatura e umidade (ITU), bem como o acompanhamento dos parâmetros fisiológicos (temperatura retal, temperatura superficial, frequência respiratória e frequência cardíaca) de 15 cabras lactantes, duas vezes por semana, nos turnos da manhã (9:00 h) e da tarde (14:00 h). O coeficiente de adaptabilidade (CA) foi estimado a partir do teste de Benezra. Os dados foram submetidos a analise de variância a 5% de probabilidade. Correlações entre as variáveis ambientais e os parâmetros fisiológicos foram realizadas através do método de Pearson (P<0,01). Os resultados mostraram que os maiores valores de temperatura ambiente, dentro e fora do galpão, foram registrados no período seco, quando as temperaturas máximas (TAmax) e mínimas (TAmin) foram maiores fora do galpão (FG) que dentro do galpão (DG). Já no período chuvoso, só houve diferença significativa às 12 h para a TAmax (FG – 30,4ºC; DG – 28,5ºC) e às 13 h para a TAmin (FG – 29,3; DG – 28,2ºC). Para umidade relativa do ar (URA) constatou-se diferença estatística (P<0,05) em todos os horários entre os períodos quanto a URAmax e URAmin, dentro e fora do galpão, sendo os valores sempre maiores no período chuvoso. O ITUmax foi mais elevado fora do galpão em todos os horários no período seco, enquanto que no período chuvoso somente entre 9 e 14 horas. Ao se comparar os períodos, o ITUmax foi maior no período chuvoso, havendo diferença significativa (P<0,05) dentro do galpão entre 9 e 12 horas e fora do galpão entre 9 e 11 horas. Para as médias de ITUmin, os maiores valores também foram observados no período chuvoso. Todos os parâmetros fisiológicos foram mais elevados à tarde e no período seco, exceto a temperatura retal (TR) que foi maior no período chuvoso. O ITU calculado no momento da coleta dos parâmetros fisiológicos, também foi maior no turno da tarde, contudo entre os períodos, foi mais elevado no período chuvoso. A TA e o ITU apresentou maior correlação com a temperatura retal (r = 0,501 e r = 0,503; P<0,01) e FR (r = 0,642 e r = 0,578; P<0,01) no período chuvoso e a temperatura superficial (TS) e do úbere (TSU) com a TA no período seco (TS - r = 0,873 e TSU - r = 0,840), mostrando que a temperatura ambiente é, isoladamente, o fator ambiental de maior impacto sobre o bem estar animal. Todas as correlações das variáveis ambientais com a freqüência cardíaca foram baixas. O CA entre as cabras variou de 4,5 a 6,0 no período seco e de 4,0 a 5,0 no período chuvoso, estando esses valores bem acima do coeficiente padrão de adaptabilidade, cujo valor é 2,0. Nas condições ambientais do presente estudo, conclui-se que independente do período do ano, as cabras Saanen estão sujeitas a um ambiente hostil, sendo o período chuvoso o mais propício a causar estresse térmico, apresentando os maiores valores de ITU e, consequentemente, de temperatura retal.
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Respostas biológicas de bovinos das raças Holandesa e Girolando sob estresse térmico / Biological responses in holstein and girolando cows under heat stress

Stumpf, Marcelo Tempel January 2014 (has links)
Trinta e oito vacas leiteiras, 19 da raça Holandês e 19 da raça Girolando (½ e ¾), foram submetidas à elevadas temperaturas por restrição à sombra durante o período entre a ordenha da manhã e da tarde. Mensurações de temperatura retal, frequências respiratória e cardíaca e escore de ofegação, além de coletas de sangue, foram realizadas nos períodos pré ordenha. Produção de leite e características físico-químicas do mesmo foram acessadas. Durante os períodos de coleta se avaliou características ambientais com vistas a calcular um índice de temperatura e umidade (ITU). Primeiramente se buscou estabelecer diferenças em parâmetros fisiológicos, de leite e sangue de vacas com diferentes porcentagens de alelos oriundos da raça Holandesa no genoma (100, 75 e 50%) em função de aumentos no ITU. Animais puros Holandês apresentaram características que condizem com menor tolerância ao calor do que animais Girolando. Em um segundo momento se analisou o efeito do estresse térmico sobre a permeabilidade das junções firmes das células epiteliais da glândula mamária de vacas Holandês. Além disso, buscou-se perceber alterações na estabilidade do leite ao teste do álcool decorrentes de um possível aumento na permeabilidade de tais estruturas celulares. O parâmetro utilizado para aferir tal efeito foi o nível sanguíneo de lactose no plasma. Alterações lácteas foram percebidas em função de aumentos de ITU e se devem principalmente à reduções em produção de leite. Aumento nos parâmetros fisiológicos não influenciou a estabilidade do leite. Leite instável apresentou maior teor de lactose. Maior número de dias em lactação pode ser o responsável pela redução na estabilidade do leite. Percebeu-se relação inversamente proporcional entre permeabilidade das junções firmes e estabilidade do leite, porém o estado de estresse térmico, ao contrário do esperado, não apresentou influência nas células da glândula mamária. / Thirty-eight dairy cows, 19 Holstein and 19 Girolando (½ e ¾), were submitted to elevated temperatures due to shade deprivation between morning and evening milkings. Rectal temperature, heart and respiratory rates and panting score measurements, besides blood samples collection, were performed before each milking. Milk production and its physical-chemical characteristics were studied. Climatic variables were measured during data collection to calculate a temperature-humidity index (THI). Firstly, the study evaluated changes in physiological, blood and milk parameters according to the percentage of alleles derived from the Holstein breed (100, 75 and 50%) due to increases in THI. Pure Holstein cows presented characteristics that indicate lower heat tolerance than Girolando cows. Secondly, heat stress effects on mammary gland cells tight junctions permeability were evaluated in Holstein cows. Alterations in milk stability due to changes in permeability were also assessed. Plasma lactose was the parameter used to detect changes in tight junctions permeability. Modifications in milk characteristics were probably due to reduction in milk production. Increase in physiological parameters did not affect milk stability. Unstable milk samples presented higher lactose levels. Higher days in milk might be the main responsible for reductions in milk stability. There was an inversely proportional relation between tight junctions permeability and milk stability to the ethanol test, although heat stress, contradicting the expected, did not influenced mammary gland cells.
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Studiu klíčivosti a vzcházivosti semen technického konopí / Study of germination and emergence of industial hemp seeds

ŘEZÁČOVÁ, Veronika January 2018 (has links)
Nowadays hemp is listed among plants with a wide range of potentials. It can be used as a source of fibre, oil, food or medicine. The aim of this work was to investigate optimal conditions for hemp seed germination grown in laboratory as well as field conditions and to propose the application of acquired findings. Hemp seed was split into 2 size groups: above 3 mm and 2 - 3 mm. Divided seeds with the humidity level of 6, 9 and 12% were stored at the temperature of 0, 8 and 20? 1°C for half a year. In 2 months interval, there were evaluated: germination, energy of sprouting, speed of sprouting, further seed viability and laboratory emergence. From next influences were evaluated the influence of dryness, wetting, autotoxicity, exudates of perennial weeds, seed treatment with the infusion of field horsetail and the grown stimulator. The best germination and laboratory emergence had seeds stored at 0°C. Test of seed viability confirmed significant decline in live seeds stored over 4 months at the 0°C temperature. The best germination was achieved by seed size 2 - 3 mm. Hemp requires sufficient amount of water for germination. Leachates from rhizomes of couch grass inhibited germination of hemp by 10%. On the other hand, germination was significantly increased by the stimulator.

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