Numerical computations of dispersed flow and gravity stratified two-phase flow

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Cryopreservation and xenografting of testis tissue

The objective of this thesis was to investigate and expand the use of testis tissue xenografting as means of maintaining the developmental potential of donor testis tissue. The objective of the first study was to investigate the effect of donor age on spermatogenesis in canine testis tissue after xenografting into immunodeficient recipient mice. Fragments of testis tissue from 12 dogs of different ages were xenografted under the back skin of mice. Donors were categorized based on testis developmental status at the time of grafting into: less than four months (immature), four to six months (young), and greater than six months of age (adult). The grafts were evaluated at four, six or eight months post-grafting. At four months post-grafting, immature and young groups had higher graft recovery rates (92 ± 5.8 and 88 ± 4.4% versus 69 ± 3.5%; P = 0.001 and P = 0.001), graft weights (34 ± 8.1 and 32 ± 11.0 mg versus 7 ± 2.6 mg; P = 0.001 and P = 0.02), vesicular gland indices (1.1 ± 0.20 and 0.6 ± 0.18% versus 0.1 ± 0.03%; P 0.05). Young donor xenografts had greater seminiferous tubule number and diameter compared to adult donor xenografts (P = 0.009 and P = 0.004, respectively) at eight months post-grafting. Elongated spermatids were the most advanced germ cell type present at four and eight months post-grafting in the testis grafts of immature and young age groups. The objective of the second study was to evaluate three different strategies to preserve/cryopreserve immature porcine testis tissue. Immature porcine testes were cooled at 4 °C for 24, 48 or 72 hours, and testis tissue fragments were cryopreserved using programmed slow freezing with dimethyl sulfoxide (DMSO), glycerol, or ethylene glycol, or vitrified using DMSO or glycerol at 5, 15 or 30 min exposure time. In vitro cell viability was determined by trypan blue exclusion, and in vivo developmental potential was evaluated by xenografting into immunodeficient mice. Compared to fresh tissue, short-term cooling of porcine testis tissue resulted in similar in vitro cell survival rates (93 ± 2.2% for fresh versus 95 ± 0.3, 93 ± 1.7 and 87 ± 4.3% after 24, 48 and 72 hours at 4 °C, respectively; P = 0.74) and in vivo development, with generation of elongated spermatids and sperm after four months of grafting. Cryopreservation of testis tissue with programmed slow freezing using glycerol and vitrification with DMSO (5 min equilibration) or glycerol (5 or 15 min equilibration) did not compromise the developmental competence of xenografts when compared to fresh tissue (control), characterized by the formation of elongated spermatids and sperm. These findings suggest that canine testis tissue from immature donors and cooling of immature porcine testis tissue to refrigerator temperature for up to 72 hours or cryopreservation with slow controlled freezing or vitrification could be suitable methods to restore male fertility following xenografting

Tree decompositions and many-sided separations

A separation of a graph $G$ is a partition $(A_1, A_2, C)$ of $V(G)$ such that $A_1$ is anticomplete to $A_2$. A classic result from Robertson and Seymour's Graph Minors Project states that there is a correspondence between tree decompositions and laminar collections of separations. A many-sided separation of a graph $G$ is a partition $(A_1, \ldots, A_k, C)$ of $V(G)$ such that $A_i$ is anticomplete to $A_j$ for all $1 \leq i < j \leq k$. In this note, we show a correspondence between tree decompositions with a certain parity property, called deciduous tree decompositions, and laminar collections of many-sided separations

Raiding the Closet: Spring 09 Look Book

This is a written report documenting the creation of a fashion “Look Book” for a boutique in downtown San Luis Obispo. This creation includes photographic art direction, styling direction, layout design, and overall theme for design

Carrier Density Dependence of sp-d Exchange in Nanostructured ZnO:Mn Thin Film

In this work, the nanostructured ZnO:Mn thin films with different Mn concentration (5, 10 and 15 mol%) have been grown on glass substrates at 500°C by the spray pyrolysis technique. The average grain size was estimated about 25 nm using SEM micrographs. The Faraday rotations were determined in applied magnetic fields up to 1.05 T. The highest values of Faraday rotation were observed in the sample with 5 mol% Mn concentration. The carrier density has been calculated from the Faraday rotations and it is observed that the sp-d exchange in magnetic semiconductor is strongly affected by carrier parameters. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3490

A Meta-Learning Approach for Custom Model Training

Transfer-learning and meta-learning are two effective methods to apply knowledge learned from large data sources to new tasks. In few-class, few-shot target task settings (i.e. when there are only a few classes and training examples available in the target task), meta-learning approaches that optimize for future task learning have outperformed the typical transfer approach of initializing model weights from a pre-trained starting point. But as we experimentally show, meta-learning algorithms that work well in the few-class setting do not generalize well in many-shot and many-class cases. In this paper, we propose a joint training approach that combines both transfer-learning and meta-learning. Benefiting from the advantages of each, our method obtains improved generalization performance on unseen target tasks in both few- and many-class and few- and many-shot scenarios.Comment: AAAI 201