There is an increased demand for artificial insemination and shipping canine semen in clinical practice. However, we need to process the semen samples using centrifugation and dilution with extenders to help preserve the breeding dose and semen quality. Our objective was to determine a clinically relevant range of centrifugation and concentration parameters for processing canine semen. In the first experiment, we hypothesized that higher g force and longer treatment improves sperm recovery rates yet causes greater decline in semen parameters over a 48-hour cooling period. Our study design used the raw semen evaluations which served as each dog's own control. Sperm RR (%) was calculated post-centrifugation, and sperm viability (%, Nucleocounter® SP-100™), total and progressive motility (%, subjective and computer-assisted sperm analysis), and morphology (NM%, eosin-nigrosin staining) were assessed on initial raw semen (T0), post-centrifugation (T1), and 24 (T2) and 48 hours (T3) after cooling. Sperm losses were minimal and similar for all treatment groups (median >98%, P≥0.062). Spermatozoa viability was not different between centrifugation groups at any time point (P≥0.38) but declined significantly during cooling (T1 vs. T2/T3, P≤0.001). Similarly, total and progressive motility did not differ across treatments but declined in all groups from T1 to T3 (P≤0.02). In conclusion, our study showed that centrifugation within a range of 400g-900g for 5-10 minutes is appropriate for processing canine semen. In the second phase, we compared different sperm concentrations for cooled canine semen storage and hypothesized that lower concentrations would result in better semen quality. Individual ejaculates were divided into a control aliquot (CON) extended 1:3 vol:vol with a commercial extender. The remaining sample was centrifuged and extended to 200 x106 sperm/ml (C200), then serially diluted to 100, 50, and 25 x106 sperm/ml concentrations (C100-C25). Aliquots were cooled for 24h, then centrifuged and re-extended. Parameters were assessed in raw semen (T0), post-extension (T1), after 24h of cooling (T2), and after processing at 24h (T3). Cooling resulted in significant declines in STM and NM for all groups, and in decreased PMI for CON and C25-50. After cooling (at T2), PMI was significantly lower for C25 compared to all groups and higher for CON compared to C25-100 (p≤0.038). For the motility parameters and NM, C25 performed worse than all or most of the other groups. Comparing CON at T3 with C25-200 at T2, PMI, STM and NM for CON were significantly lower than C25-200, C200, and C100-200, respectively. In conclusion, our results show that cooling canine semen for 24h at 200 x106 sperm/ml final concentration after processing or extending 1:3 vol:vol without centrifugation is preferred based on highest PMI. If volume restrictions apply, processing raw semen and extending to the desired volume with higher sperm concentrations at the collection facility is superior to centrifugation and volume adjustment after 24h of cooled storage. / Master of Science / We need to process canine semen using centrifugation and dilution for cooled shipments or cryopreservation. This is due to the increased demand for shipping canine semen for artificial insemination. Our goal was to define an acceptable range of centrifugation and concentration parameters (gravitational (g) force and time and sperm/ml) without severe negative impact on semen quality. In the first experiment, we hypothesized that higher g force (900g vs. 400g or 720g) and longer treatment (10 min. vs. 5 min.) improves sperm recovery rates yet causes greater decline in semen parameters over a 48-hour cooling period. Initial raw semen evaluations served as each dog's own control. Sperm recovery rates post-centrifugation were similar between treatment groups. Sperm viability, motility and morphology were not different between centrifugation treatment groups but declined over time. In conclusion, our range of 400-900g for 5-10 minutes centrifugation provides clinically viable semen quality after up to 48 hours of cooled storage in dogs. In the second phase, we compared different sperm concentrations for cooled canine semen storage and hypothesized that lower concentrations would result in better semen quality. Individual ejaculates were divided into a control aliquot (CON) extended 1:3 vol:vol with a commercial extender. The remaining sample was centrifuged and extended to 200 x106 sperm/ml (C200), then serially diluted to 100, 50, and 25 x106 sperm/ml concentrations (C100-C25). Aliquots were cooled for 24h, then centrifuged and re-extended. Cooling resulted in significant declines in subjective total motility and normal morphology (NM, %) for all groups, and in decreased viability for CON and C25-50. After cooling, viability of the sperm cells was significantly lower for C25 compared to all other groups, and higher for CON compared to C25-100 (P≤0.038). For motility parameters and NM, C25 performed worse than all or most of the other groups. In conclusion, our results show that cooling canine semen for 24h at 200 x106 sperm/ml final concentration after processing or extending 1:3 vol:vol without centrifugation is preferred based on highest plasma membrane integrity (PMI) or sperm cell viability. If volume restrictions apply, processing raw semen and extending to the desired volume with higher sperm concentrations at the collection facility is superior to centrifugation and volume adjustment after 24h of cooled storage.

Actuellement, le secteur des nanotechnologies est en développement intense. Les nanoparticules de dioxyde de titane et d¿or occupent une part importante de ce secteur, avec des applications utilisant principalement leurs propriétés optiques et catalytiques. Les synergies pouvant exister entre les nanoparticules d¿or et leur support, en particulier via l¿effet plasmon, permettent de modifier la réponse optique de dispositifs catalytiques ou photovoltaïques. Une nouvelle technique polyvalente de mise en forme de film mésoporeux à base de nanoparticules de dioxyde de titane et d¿or a été développée. L¿utilisation de différentes méthodes de synthèse des nanoparticules a permis le contrôle de la morphologie et des propriétés physiques des films déposés par centrifugation. Finalement, l¿adéquation de ces films à leur utilisation en tant qu¿anode de cellules solaires à colorant a été évaluée. / Nanotechnologies represent a fast growing market. Gold and titanium dioxide nanoparticles are an important part of this market, thanks to their optical and catalytic properties. Existing synergies between gold nanoparticles and their substrate, mainly via the plasmonic effect, allow modifying the optical response of catalytic and photovoltaic systems. A new versatile approach is proposed to form mesoporous nanostructures composed of gold and titanium dioxide nanoparticles. The use of various syntheses allowed the formation of nanoparticles leading to a good control upon aggregation morphology and physical properties of centrifuged films. Finally, appropriateness of these films for a use as dye sensitized solar cell anodes was evaluated.

Submitted by Samira Ramos (samira.ramos@unifenas.br) on 2019-02-26T16:35:22Z No. of bitstreams: 1 Amarildo_Marciano_Rosa.pdf: 697737 bytes, checksum: f45cb56a60aced2c55ace1d99ecec4f0 (MD5) / Made available in DSpace on 2019-02-26T16:35:22Z (GMT). No. of bitstreams: 1 Amarildo_Marciano_Rosa.pdf: 697737 bytes, checksum: f45cb56a60aced2c55ace1d99ecec4f0 (MD5) Previous issue date: 2018-06-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The objective of this study was to evaluate the influence of the use of single-layer colloidal silica of glycidoxypropyltrimethoxysilane-equine formulation-Androcoll-E® (Minitube, Germany) on the freezing of canine semen. For this, 5 dogs, of different breeds, with satisfactory semen characteristics (CBRA, 2013) were used. Seven ejaculates / animal were collected and subdivided, forming: Group A - samples centrifuged at 300g for 10 minutes using Androcoll-E® and group E samples centrifuged at 700g for 10 minutes using CaniPlus Enhance® medium (Minitube; Germany). In both groups, the steps of discarding the supernatant, resuspension of the pellet in CaniPlus Enhance® (1mL of medium / 100 x 106 spermatozoa), packaging (25 x 106 spermatozoa / pallet), refrigeration (2 to 6ºC for 2 hours) , freezing (20 minutes at 5cm over N2 vapor and storage at -196C in N2 canister) and thawing (at 37 ° C for 60 seconds). After 7 days, the samples were resubmitted to centrifugation, forming 4 subgroups (16 straws / animal / subgroup): AA (Androcoll-E® centrifugation in the pre- and post-thawing stage), AE (Androcoll-E® centrifugation at pre-freezing stage and CaniPlus Enhance® in post-thawing), EA (CaniPlus Enhance® centrifugation in pre-freezing and with Androcoll-E® after thawing) and EE (CaniPlus Enhance® centrifugation in pre and post-thaw stages). Microscopic analysis of semen (concentration, vigor, membrane integrity, sperm morphology, subjective and computerized motility) was performed. Test of variance, Tukey and Kruskall Wallis were used, considering p <0.05. There was a statistical difference in relation to computerized motility and sperm morphology. The mean trajectory velocity and curvilinear velocity were higher in the EE group, the cross flagellar beating and the rectilinearity in the EA group and the linearity in the AA group. In relation to sperm morphology, the EA group presented the highest percentage of morphologically intact cells (95%), whereas in the AE group, minor defects (23%) and higher were greater than acceptable (12%). The use of equine colloidal silica after thawing (EA group) selects morphologically intact spermatozoa, which present parameters that indicate a better migration capacity and penetration into the cervical mucus. / O objetivo deste estudo foi avaliar a influência do uso da centrifugação em camada única de sílica coloidal de glicidoxipropiltrimetoxissilano- formulação equina-Androcoll-E® (Minitube, Germany), na congelação do sêmen canino. Para isso, 5 cães, de raças distintas, com características seminais satisfatórias (CBRA, 2013) foram utilizados. Sete ejaculados/animal foram coletados e subdivididos, formando: Grupo A- amostras centrifugadas a 300g, por 10 minutos, utilizando Androcoll-E® e grupo E- amostras centrifugadas a 700g, por 10 minutos, utilizando o meio CaniPlus Enhance® (Minitube; Germany). Em ambos os grupos foram realizadas as etapas de descarte do sobrenadante, ressuspensão do pellet em CaniPlus Enhance® (1mL de meio/100 x 106espermatozoides), envase (25 x 106 espermatozoides móveis/palheta), refrigeração (2 a 6ºC por 2 horas), congelação (20 minutos a 5cm sobre vapor de N2 e armazenamento a -196ºC em botijão de N2) e descongelação (a 37ºC por 60 segundos). Após 7 dias, as amostras foram ressubmetidas à centrifugação, formando 4 subgrupos (16 palhetas/animal/subgrupo): AA (centrifugação com Androcoll-E® na etapa de pré e pós descongelação), AE (centrifugação com Androcoll-E® na etapa pré congelação e com CaniPlus Enhance® na pós descongelação), EA (centrifugação com CaniPlus Enhance® na pré congelação e com Androcoll-E® na pós descongelação) e EE (centrifugação com CaniPlus Enhance® nas etapas pré e pós descongelação). A análise microscópica do sêmen (concentração, vigor, integridade de membrana, morfologia espermática, motilidade subjetiva e computadorizada) foi realizada. Teste de variância, Tukey e Kruskall Wallis foram usados, considerando p<0,05. Houve diferença estatística em relação à motilidade computadorizada e morfologia espermática. A velocidade média da trajetória e curvilínea foram superiores no grupo EE, o batimento flagelar cruzado e a retilinearidade no grupo EA e a linearidade no grupo AA. Em relação à morfologia espermática, o grupo EA foi o que apresentou maior porcentagem de células morfologicamente íntegras (95%) enquanto no grupo AE, os defeitos menores (23%) e maiores foram superiores aos aceitáveis (12%). O uso da centrifugação com sílica coloidal equina pós descongelação (grupo EA) seleciona espermatozoides morfologicamente íntegros, que apresentam parâmetros que indicam melhor capacidade de migração e penetração no muco cervical.

Reproduction de : Thèse de doctorat : Matériaux-Structure-Mécanique : Toulouse, INPT : 2004. / Titre provenant de l'écran-titre. Bibliogr. 192 réf.

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Bibliography: leaves 208-216. / xxii, 231 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / The aim of this thesis is to define optimal centrifuge operating conditions for inclusion body recovery. Special attention is directed to the interaction of the recovery step with upstream and downstream processes. A new Eschenchia coli debris sizing method, Asoc, is developed to overcome the limitations of existing sizing methods. / Thesis (Ph.D.)--University of Adelaide, Dept. of Chemical Engineering, 1997?

Thesis (Ph.D.)--University of Delaware, 2008. / Principal faculty advisors: Steven K. Dentel, Dept. of Civil & Environmental Engineering; and Diane S. Herson, Dept. of Biological Sciences. Includes bibliographical references.

Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2004. / Includes bibliographical references (leaves 146-151). Also available in electronic version. Access restricted to campus users.

Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references (leaves 266-279). Also available in electronic version. Access restricted to campus users.

Th. doct.-ing.--Génie chim.--Toulouse--I.N.P., 1985. N°: 359.