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Effect of cryoprotectant on the cryopreservation of
M.H Mapeka, K.C Lehloenya, T.L Nedambale, B Sutherland
South African Journal of Animal Science , 2009,
Abstract: The study evaluated the effect of different cryoprotectants on post-thaw survival and motility of Kolbroek sperm. Semen from Kolbroek boars was collected with the gloved hand technique. Ejaculates were diluted with Beltsville thawing solution (BTS) at a ratio of 1 : 1 prior to freezing. Semen was diluted with egg yolk tris; thereafter, one of the three cryoprotectants (14% glycerol, 14% DMSO or 7% glycerol + 7% DMSO) were added. Diluted samples were then loaded into 0.5 mL straws and cooled with a programmable freezer. Thereafter the semen straws were plunged directly into liquid nitrogen (-196 °C) and stored for 48 h. Frozen straws were thawed at 39 °C for a minute and evaluated for sperm motility and survival at 0, 30, 60 and 90 min post-thaw. The post-thaw sperm survival frozen using glycerol as a cryoprotectant was significantly higher immediately after thawing, compared to DMSO, however, similar to the combination of glycerol and DMSO. There was no significant difference on motility rate immediately (0 min) post-thaw between the three cryoprotectants. Sperm cryopreserved with glycerol exhibited a significantly higher percentage motility at 30, 60 and 90 min post-thaw than in the other cryoprotectants. Based on sperm motility, glycerol was a better cryoprotectant for cryopreservation of Kolbroek boar sperm.
A bottle in a freezer  [PDF]
Pavel Krejci,Elisabetta Rocca,Juergen Sprekels
Mathematics , 2009,
Abstract: We propose here a model for solidification of a liquid contents of an elastic bottle in a freezer. The main goal is to explain the occurrence of high stresses inside the bottle. As a by-product, we derive a formula for the undercooling coefficient in terms of the elasticity constants, latent heat, and the phase expansion coefficient. We investigate the well-posedness of the three-dimensional model: we prove the existence and uniqueness of a solution for the corresponding initial-boundary value problem which couples a PDE with an integrodifferential equation and an ordinary differential inclusion ruling the evolution of the phase parameter. Finally, we prove some results on the long time behavior of solutions.
Resurrection axioms and uplifting cardinals  [PDF]
Joel David Hamkins,Thomas A. Johnstone
Mathematics , 2013,
Abstract: We introduce the resurrection axioms, a new class of forcing axioms, and the uplifting cardinals, a new large cardinal notion, and prove that various instances of the resurrection axioms are equiconsistent over ZFC with the existence of an uplifting cardinal.
Absoluteness via Resurrection  [PDF]
Giorgio Audrito,Matteo Viale
Mathematics , 2014,
Abstract: The resurrection axioms are forms of forcing axioms that were introduced recently by Hamkins and Johnstone, developing on ideas of Chalons and Velickovic. We introduce a stronger form of resurrection axioms (the iterated resurrection axioms) and show that they imply generic absoluteness for the first-order theory of $H_{\mathfrak{c}}$ with parameters with respect to various classes of forcing. We also show that the consistency strength of these axioms is below that of a Mahlo cardinal for most forcing classes, and below that of a stationary limit of supercompact cardinals for the class of stationary set preserving posets. We also compare these results with the generic absoluteness results by Woodin and the second author.
Effect of cryoprotectant on the cryopreservation of South African Kolbroek pig semen
MH Mapeka, KC Lehloenya, TL Nedambale, B Sutherland
South African Journal of Animal Science , 2010,
Abstract: The study evaluated the effect of different cryoprotectants on post-thaw survival and motility of Kolbroek sperm. Semen from Kolbroek boars was collected with the gloved hand technique. Ejaculates were diluted with Beltsville thawing solution (BTS) at a ratio of 1 : 1 prior to freezing. Semen was diluted with egg yolk tris; thereafter, one of the three cryoprotectants (14% glycerol, 14% DMSO or 7% glycerol + 7% DMSO) were added. Diluted samples were then loaded into 0.5 mL straws and cooled with a programmable freezer. Thereafter the semen straws were plunged directly into liquid nitrogen (-196 °C) and stored for 48 h. Frozen straws were thawed at 39 °C for a minute and evaluated for sperm motility and survival at 0, 30, 60 and 90 min post-thaw. The post-thaw sperm survival frozen using glycerol as a cryoprotectant was significantly higher immediately after thawing, compared to DMSO, however, similar to the combination of glycerol and DMSO. There was no significant difference on motility rate immediately (0 min) post-thaw between the three cryoprotectants. Sperm cryopreserved with glycerol exhibited a significantly higher percentage motility at 30, 60 and 90 min post-thaw than in the other cryoprotectants. Based on sperm motility, glycerol was a better cryoprotectant for cryopreservation of Kolbroek boar sperm.
The effect of two cryoprotectant mixtures on frozen surubí surimi
Medina, J.R.;Garrote, R.L.;
Brazilian Journal of Chemical Engineering , 2002, DOI: 10.1590/S0104-66322002000400010
Abstract: "surimi" itself is not a food; it is an intermediate phase of the production of "kamaboko"(a gel formed by the addition of salt to the surimi and direct heating to 80-90oc) and a series of high-priced shellfish analogs. the protective effect that two cryoprotectant mixtures exerted during freezing and frozen storage of frozen surimi of surubí (pseudoplatystoma coruscans) on the functional quality of the gels prepared was studied. the selected washing conditions selected to obtain an acceptable functional quality of gels prepared from frozen surimi (25% extracted proteins and of final moisture) using the response surface methodology were wash temperature, 18oc; washing time for each of the three washing cycles, 4.62 min. and water-mince ratio, 3.5:1. cryoprotectant mixtures used were sucrose/sorbitol (1:1) and maltodextrin/sorbitol (1:1) and they were added (8%) to the washed and drained minced fish before freezing. to evaluate the functionality of the frozen surimi during six months of storage, the penetration test to measure the gel strength was chosen; samples were assessed at 4, 45, 90 and 180 days of frozen storage. results showed that even with the cryoprotectants freezing decreased gel strength, since it produced a decrease of almost 32% in the strength of the gel prepared with fresh surimi. however, the two cryoprotectant mixtures tested showed very good behaviour throughout frozen storage; specially at 45 and 90 days of storage the surimi gels with the sucrose/sorbitol mixture had a greater resistance than those with maltodextrin/sorbitol.
The effect of two cryoprotectant mixtures on frozen surubí surimi  [cached]
Medina J.R.,Garrote R.L.
Brazilian Journal of Chemical Engineering , 2002,
Abstract: "Surimi" itself is not a food; it is an intermediate phase of the production of "kamaboko"(a gel formed by the addition of salt to the surimi and direct heating to 80-90oC) and a series of high-priced shellfish analogs. The protective effect that two cryoprotectant mixtures exerted during freezing and frozen storage of frozen surimi of surubí (Pseudoplatystoma coruscans) on the functional quality of the gels prepared was studied. The selected washing conditions selected to obtain an acceptable functional quality of gels prepared from frozen surimi (25% extracted proteins and of final moisture) using the response surface methodology were wash temperature, 18oC; washing time for each of the three washing cycles, 4.62 min. and water-mince ratio, 3.5:1. Cryoprotectant mixtures used were sucrose/sorbitol (1:1) and maltodextrin/sorbitol (1:1) and they were added (8%) to the washed and drained minced fish before freezing. To evaluate the functionality of the frozen surimi during six months of storage, the penetration test to measure the gel strength was chosen; samples were assessed at 4, 45, 90 and 180 days of frozen storage. Results showed that even with the cryoprotectants freezing decreased gel strength, since it produced a decrease of almost 32% in the strength of the gel prepared with fresh surimi. However, the two cryoprotectant mixtures tested showed very good behaviour throughout frozen storage; specially at 45 and 90 days of storage the surimi gels with the sucrose/sorbitol mixture had a greater resistance than those with maltodextrin/sorbitol.
Strongly uplifting cardinals and the boldface resurrection axioms  [PDF]
Joel David Hamkins,Thomas A. Johnstone
Mathematics , 2014,
Abstract: We introduce the strongly uplifting cardinals, which are equivalently characterized, we prove, as the superstrongly unfoldable cardinals and also as the almost hugely unfoldable cardinals, and we show that their existence is equiconsistent over ZFC with natural instances of the boldface resurrection axiom, such as the boldface resurrection axiom for proper forcing.
The origin of the resurrection idea: A dialogue with George Nickelsburg  [cached]
P.J.W. (Flip) Schutte
HTS Theological Studies/Teologiese Studies , 2009, DOI: 10.4102/hts.v64i2.52
Abstract: This is a review article on George W E Nickelsburg’s book Resurrection, immortality, and eternal life in intertestamental Judaism and early Christianity. The aim of this article is to reflect on the results of Nickelsburg’s research with regard to the earliest Christians’ understanding of Jesus’ resurrection. Nickelsburg investigated the topic of the afterlife in intertestamental Judaism and early Christianity from three perspectives namely, resurrection, immortality, and eternal life. The book focuses on the origins of these perspectives and the dynamics involved in the development of theological understanding of Jesus’ resurrection in earliest Christianity. Part one of the article represents the content of Nickelsburg’s book, and part two consists of comments debating the results that Nickelsburg puts on the table.
DEVELOPMENT OF A CHEST FREEZER – OPTIMUM DESIGN OF AN EVAPORATOR COIL  [PDF]
K. Kalyani Radha,S. Naga Sarada,K. Rajagopal
International Journal of Automotive and Mechanical Engineering , 2012,
Abstract: In a country such as India, food grains, fruit, vegetables, meat, poultry and fish, are very susceptible to microbial contamination and spoilage and require stringent preservation methods. One such method is by the use of a chest freezer for the storage of frozen food. This investigation considers different loads and design parameters for the development of a chest freezer using R134a as the working fluid. Experimental designs of an evaporator coil, condenser coil and capillary tube are investigated through the development of storage periods in terms of steady state and cyclic performance, by optimising the quantity of refrigerant charge, with strict adherence to the standards and requirement for maintaining an internal temperature of -23 °C at 43 °C ambient. Cyclic load performance tests optimise the performance of individual components selected for the design of a chest freezer. The system selection has a highly balanced performance with R134a and showed 118 kJ/kg cooling capacity with 8.42 coefficient of performance (COP). By the replacement of R134a, temperatures of -23 °C are maintained inside the freezer cabinet with low power consumption and an increase in the net refrigerating effect, which in turn increases the COP. The system design has optimum efficiency with moderate costs by optimising the length and diameter of the evaporator coil, i.e., 34.15 m and 7.94 mm, respectively.
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