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In vitro produced (IVP) embryos not hatching from the zona pellucida (ZP) after transfer is one possible contributing factor of a lower pregnancy rate when compared to in vivo embryos. This study evaluates using a microscope objective mounted laser to cut the ZP prior to transfer into the recipient to assist hatching. The preliminary data evaluated the effect of laser treatment on IVP embryos and subsequent blastomere survival. In six replicates, bovine oocytes were in vitro produced according to the standard laboratory procedures of TransOva Genetics, Sioux Center, IA. On days 5, 6, and 7 of in vitro culture, embryos were randomly divided into 3 groups: no treatment (Control; n=63), sham ZP cut (Sham; n=68), or ZP cut (Cut; n=70). Control embryos were immediately returned to the incubator. Sham embryos were exposed to all conditions as Cut except laser assisted hatching. The XyClone® system was used to treat the Cut group using pulse strength of 90% and pulse length of 600 μsec. Embryos were returned to culture until day 8 when embryonic development and the percentage of live cells were determined and analyzed with Chi square. The number of developing embryos and the percentage of live cells per embryo showed no significant difference. Mean live cells ranged from 89-96% regardless of day of treatment. The laser assisted hatching effect on IVP embryo viability was evaluated by randomly dividing commercially produced embryos obtained from TransOva Genetics into two groups on day of transfer, Control or Cut. The ZP of treated embryos were cut with the laser using 80% pulse strength and pulse length of 500 μsec on day 7, immediately prior to transfer into estrous synchronized recipients. Ultrasonagraphy determined pregnancy rates. Thirty day pregnancy rates were 49.2% and 54.1% for Control (n= 189) and Cut (n=148) embryos, respectively, and were not statistically different (p > 0.05). However, 60 day Control pregnancy rate was 45.7% (n= 166) and the Cut group rate was 57.7% (n= 123) revealing a statistical difference (p < 0.05). These results demonstrate that the XyClone® system assisted hatching can improve 60 day pregnancy rates for IVP embryos by approximately 11 %.

In vitro produced (IVP) embryos not hatching from the zona pellucida (ZP) after transfer is one possible contributing factor of a lower pregnancy rate when compared to in vivo embryos. This study evaluates using a microscope objective mounted laser to cut the ZP prior to transfer into the recipient to assist hatching. The preliminary data evaluated the effect of laser treatment on IVP embryos and subsequent blastomere survival. In six replicates, bovine oocytes were in vitro produced according to the standard laboratory procedures of TransOva Genetics, Sioux Center, IA. On days 5, 6, and 7 of in vitro culture, embryos were randomly divided into 3 groups: no treatment (Control; n=63), sham ZP cut (Sham; n=68), or ZP cut (Cut; n=70). Control embryos were immediately returned to the incubator. Sham embryos were exposed to all conditions as Cut except laser assisted hatching. The XyClone® system was used to treat the Cut group using pulse strength of 90% and pulse length of 600 μsec. Embryos were returned to culture until day 8 when embryonic development and the percentage of live cells were determined and analyzed with Chi square. The number of developing embryos and the percentage of live cells per embryo showed no significant difference. Mean live cells ranged from 89-96% regardless of day of treatment. The laser assisted hatching effect on IVP embryo viability was evaluated by randomly dividing commercially produced embryos obtained from TransOva Genetics into two groups on day of transfer, Control or Cut. The ZP of treated embryos were cut with the laser using 80% pulse strength and pulse length of 500 μsec on day 7, immediately prior to transfer into estrous synchronized recipients. Ultrasonagraphy determined pregnancy rates. Thirty day pregnancy rates were 49.2% and 54.1% for Control (n= 189) and Cut (n=148) embryos, respectively, and were not statistically different (p > 0.05). However, 60 day Control pregnancy rate was 45.7% (n= 166) and the Cut group rate was 57.7% (n= 123) revealing a statistical difference (p < 0.05). These results demonstrate that the XyClone® system assisted hatching can improve 60 day pregnancy rates for IVP embryos by approximately 11 %.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第20952号 / 理博第4404号 / 新制||理||1633(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 沼田 英治, 准教授 森 哲, 教授 中川 尚史 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM

Morley, S. A. (1998). Environmental and parental influences on the size of herring larvae. Ph.D. thesis submitted to the University of Liverpool for the degree of Doctor of Philosophy Investigations were carried out into the effects of mean egg dry weight and incubation temperature on the size of larvae from four N.E. Atlantic herring stocks (Buchan, Manx, Clyde and Celtic Sea). Hatching characterisitics (length, weight and yolk volume) of Buchan, Manx and Clyde herring were investigated. The time of hatching was inversely related to incubation temperature, although there was some variation between experiments in the date of peak hatching. The total length of larvae increased through the hatching period. In all experiments mean egg dry weight per female was strongly related to the average length, weight and yolk volume of larvae at hatching. The same regression model could be applied to all stocks. There were, however, stock-specific responses of hatching characteristics to incubation temperature although a reduction in length at hatching at higher temperatures was the most consistent response. Development at low temperature resulted in a modification of the length-weight relationship; larvae of the same weight were longer at lower temperatures. Both the increase in length of larvae during the hatching period and the variation in the timing of peak hatching have implications for the comparison of larvae hatching at different temperatures. The otoliths of Manx herring larvae [from "large" (> 0.33mg mean dry weight) and "small" «0.2Smg mean dry weight) eggs] were marked with either alizarin complexone or calcein so that larvae from pairs of large and small egg batches could be reared under identical conditions (at both 10 and I3.S0C) and relative growth monitored. Within each rearing tank large eggs generally produced larger larvae at hatch (length and weight) with higher growth rates (both weight and length specific). There were significant differences both between eggs from different females and between rearing tanks that confounded the comparisons between rearing temperatures. Fultons Condition factor is not thought to be a good measure of nutritional condition of herring larvae smaller than ISmm total length but may be used as a relative measure of body reserves (ReF) and give an indication of ability to withstand periods of poor feeding. This is indicated by a period of high mortality of larvae hatched from small eggs at 10°C, which corresponded with the time period when these larvae had the lowest body reserves. Video recording of the foraging behaviour of laboratory reared herring larvae was used to investigate differences between the feeding strategies of groups of larvae of the same size but different ages, i.e. fast and slow growers. Slow growing larvae searched larger areas, thus expending more energy, than fast growing larvae, but there was no difference in food acquisition. The difference in behaviour tended to increase through development A simple energetics calculation suggested that approximately 50% of the difference in growth rate could be explained by the extra swimming costs of slower growing larvae. The size of Celtic Sea and Manx herring eggs were experimentally reduced in order to investigate if the volume of yolk in each egg determines the size of hatching larvae. Length at hatch was determined by the volume of yolk in each egg but body weight was not. The development and chemical composition of embryos and larvae needs to be investigated in a further series of experiments. All results are discussed in terms of the influence of larval size on survival.

In this thesis, the morphology, crystallization and melting behavior of polypropylene copolymers (propylene/ethylene, propylene/1-butene, propylene/1-hexene and propylene/1-octene) has been examined. The multiple melting behavior has been correlated with the presence of alpha and gamma phases and with the occurrence of cross-hatching morphology. The Crystallization and melting behavior of propylene/ethylene and propylne/1-butene are qualitatively similar and compatible with the expectations that the ethylene and butene comonomers are partly included in the propylene lattice. Propylene/1-hexene and propylene/1-octene copolymers exhibit remarkably similar behavior and morphologies consistent with the expectations that the hexene and the octene comonomers are rigorously excluded from the crystal lattice. The origin and the crystallization time dependence of the multiple melting behavior is very different for these two pairs of copolymers. For PE and PB it is consistent with the melting of parent a-phase lamellae and alpha or gamma-phase daughter lamellae. For PH and PO copolymers it is very similar to that observed for ethylene-octene(EO) and ethylene-styrene(ES) copolymers and compatible with the melting of primary lamellae and secondary mosaic or fringed micellar structures. / Master of Science

Much research has been done in creating non-photorealistic renderings of objects that mimic the look of hand-made drawings by traditional artists. This thesis extends work in this area by presenting an NPR hatching method that can be applied to 3D animated films to help them feel more hand drawn. In contrast to most other NPR methods, this method preserves the 3D lighting and effects of the film that make it interesting to watch. This process includes a procedural algorithm to create a hatching pattern that can be easily integrated into any film's pipeline that uses Renderman. In addition, we create a set of controls to adjust the hatching that are easy to use and allow our style to be applied to many different objects in many shots of a film in an efficient manner. To show the success of our method, we will discuss the implementation and results of applying it to an actual 3D animated short film.

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第19018号 / 農博第2096号 / 新制||農||1029(附属図書館) / 学位論文||H27||N4900(農学部図書室) / 31969 / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 近藤 直, 教授 飯田 訓久, 准教授 小川 雄一 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM

For many organisms, embryonic development begins directly after an egg (ovum) has been fertilized by sperm; however, some organisms delay the onset of embryonic development until conditions are favorable for raising young. This delayed onset of development could occur by delaying implantation of fertilized ovum on the uterine wall, as seen in many mammals. Birds delay embryonic development by laying a set of fertilized ova over a period of consecutive days. These fertilized ova are protected from the ambient environment by an exterior shell, and it is in this shell outside of the female s body that embryonic development occurs, but only when females initiate incubation. The number of fertilized ova (eggs) that can be laid by a single female in a single clutch varies among and within bird species, and understanding this variation remains a vital, unanswered question in ornithology. A latitudinal gradient in clutch size is widely recognized, but the reason for this pattern is unclear. Some birds lay relatively large clutches over many days, thus we should expect that eggs could withstand fairly long exposure to ambient temperature and remain viable. However, recent evidence suggests that egg viability declines with increased exposure to ambient temperatures. The egg viability hypothesis predicts that eggs will fail to hatch if exposed to warm ambient temperatures for prolonged periods. I conducted a natural experiment to determine whether egg viability can explain site-specific variation in hatching failure. Hatching failure is higher in a suburban population of Florida Scrub-Jays than it is in a wildland population, possibly because suburban scrub-jays lay larger clutches. Scrub-jays, like many bird species, lay one egg per day and begin incubation with the last-laid egg, thus first-laid eggs in the larger suburban clutches should be exposed to the warm ambient temperatures of sub-tropical Florida longer than first-laid eggs in the smaller clutches typical of the wildland population. As predicted, I found hatching failure is higher in first-laid eggs in the suburbs, and these eggs experience increased exposure to warm ambient temperatures. At both sites, females appear to begin incubation earlier in the laying period as ambient temperatures increase seasonally, possibly to minimize exposure to warm ambient temperatures and minimize hatching failure in first-laid eggs. However, early onset of incubation causes eggs to hatch asynchronously ( > 24 hours between the first and last-hatched egg), and hatching asynchrony increases within-brood size-asymmetries, which leads to an increased frequency of brood reduction (the nonrandom loss of last-hatched young because of starvation). Thus, a tradeoff may exist between beginning incubation earlier in the laying period to minimize hatching failure in first-laid eggs and delaying the onset of incubation to minimize hatching asynchrony and brood reduction. This tradeoff can have profound effects on avian clutch sizes, and may potentially explain the widely known negative relationship between latitude and clutch size.

Effects of artificial water fluctuations called hydropeaking on the detachment rates of adhesive eggs were studied using a rheophlic fish (asp Leuciscus aspius) as a model species. I attempted to relate egg density to abiotic conditions of the spawning ground and identify optimal conditions for the eggs. Egg densities were also studied during spawning season when hydropeaking occurred. In the experimental setup, egg detachment rates were tested with different speeds, substrate type and exposition time and critical conditions for the eggs were assessed.