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Pyrolysis and oxidation of triethyl phosphate (TEP) were performed in the reflected shock region at temperatures of 1462–1673 K and 1213–1508 K, respectively, and at pressures near 1.3 atm. CO concentration time histories during the experiments were measured using laser absorption spectroscopy at 4580.4 nm. Experimental CO yields were compared with model predictions using the detailed organophosphorus compounds (OPC) incineration mechanism from the Lawrence Livermore National Lab (LLNL). The mechanism significantly underpredicts CO yield in TEP pyrolysis. During TEP oxidation, predicted rate of CO formation was significantly slower than the experimental results. Therefore, a new improved kinetic model for TEP combustion was developed, which was built upon the AramcoMech2.0 mechanism for C0-C2 chemistry and the existing LLNL submechanism for phosphorus chemistry. Thermochemical data of 40 phosphorus (P)-containing species were reevaluated, either using recently published group values for P-containing speci...

As the expression of the LH receptor (LH-R) in granulosa cells is thought to be associated with later stages of folliculogenesis, this study was undertaken to evaluate the presence of LH-R mRNA as a suitable marker for developmental competence of oocytes. Granulosa cells and cumulus-oocyte complexes (COCs) were recovered from cows that had received ovarian stimulation. The COCs were subjected to embryo production procedures in vitro to assess the embryonic potential of the oocyte, and the corresponding granulosa cells were used to evaluate the presence of LH-R mRNA by RT-PCR. The presence of LH-R transcripts in granulosa cells is not a key characteristic of a follicle bearing a competent oocyte, although a higher proportion of oocytes reach the blastocyst stage when LH-R mRNA is detected in the granulosa cells. Different LH-R isoforms were cloned and sequence discrepancies among six of the isoforms enabled the design of specific oligonucleotides to study the presence of the isoforms in different follicular cells. All LH-R transcripts studied and the 80 kDa protein product corresponding to the full length receptor were found in granulosa cells of small (< 4 mm) and large (> 5 mm) follicles. When the granulosa cells were cultured, the transcripts were downregulated by the culture conditions; downregulation was more acute in granulosa cells from small follicles. The addition of LH to the culture media enhanced LH-R mRNA downregulation. The presence of several LH-R transcript isoforms was tissue specific and in the theca cells LH-R mRNA was restricted mainly to cells from larger follicles. This finding indicates that the expression and the splicing of LH-R mRNA are regulated in a cell-specific and follicular size-specific manner.

Superstimulation in donor cows increases the number of cumulus-oocyte complexes (COC), but when compared to in vivo maturation, in vitro maturation results in only half as many blastocysts after prolonged in vitro culture. The objective of this study was to establish a superstimulation protocol that would produce a maximal number of competent COC for standard in vitro embryo production. During experiment 1, eight cyclic Holstein heifers were superstimulated with four doses of FSH. Half the heifers received an injection of LH 6 h before ovum pick-up (OPU). The COC were collected following OPU either 33 or 48 h following the last FSH injection (coasting period). During experiment 2, six cyclic Holstein heifers were superstimulated with six doses of FSH, and in half the heifers, LH was administered 6 h before OPU. The COC were collected following ultrasound-guided transvaginal aspiration of both ovaries 48 h after the last FSH injection (coasting period). The COC originating from follicles with a diameter of 5 mm or more (n = 180 for experiment 1 and 57 for experiment 2) were subjected to standard in vitro maturation, fertilization, and development. When animals were administered four doses of FSH, 48 h of coasting resulted in significantly more 5- to 10-mm follicles (P < 0.01) than 33 h of coasting. If a 33-h coasting period was used, administration of LH 6 h before OPU resulted in a significant increase in both percentage of blastocysts and embryo production rate at Days 7 and 8 (P ≤ 0.05) of in vitro culture. If a 48-h coasting period was used, LH injection did not affect the rates of blastocyst production. When donors were administered six doses of FSH with a 48-h coasting period, the highest results, although not significant (P < 0.08), were obtained when animals received LH 6 h before OPU, with 80% ± 9% (mean ± SEM) blastocysts and 0.8 ± 0.09 embryo produced per COC retrieved per heifer at Day 8 of culture. Never has in vitro technology been so close to producing 100% developmentally competent COC.

The main objective of this study was to identify mRNA expressed in the granulosa cells characterizing differentiated follicles bearing developmentally competent bovine oocytes. Analytical comparisons were made on mRNA pools of granulosa cells using differential display reverse transcription polymerase chain reaction (DDRT) analysis and suppressive subtractive hybridization (SSH). With DDRT, mRNA patterns of granulosa cells from small ( 8 mm) follicles cultured in the presence or absence of LH were compared to identify mRNA associated with follicular size or with the LH response. Nine clones were sequenced, and two were identified. One of the clones, DRAK 1, was associated with the presence of LH in the medium. Other comparisons directed toward the identification of mRNA associated with the presence of a competent oocyte were done on granulosa cells collected in vivo from superstimulated heifers. With the DDRT analysis, four clones associated with the oocyte developmental competence status were identified. With the SSH analysis, four clones specific to the presence of an incompetent oocyte were sequenced and none were identified, whereas 49 clones specific to the presence of a competent oocyte were sequenced and 18 were identified. Among these clones, early growth response 1, sprouty 2, cytochrome C oxidase, matrix metalloproteinase inducer, matrix metalloproteinase, epiregulin, prostaglandin receptor, and progesterone receptor were the most relevant to the ovarian physiology being examined.

There were four groups that worked on this project in different areas related to Smart Girds and Security. They included faculty and students from electric computer and energy engineering, law, business and sociology. The results of the work are summarized in a verity of reports, papers and thesis. A major report to the Governor of Colorado’s energy office with contributions from all the groups working on this project is given bellow. Smart Grid Deployment in Colorado: Challenges and Opportunities, Report to Colorado Governor’s Energy Office and Colorado Smart Grid Task Force(2010) (Kevin Doran, Frank Barnes, and Puneet Pasrich, eds.) This report includes information on the state of the grid cyber security, privacy, energy storage and grid stability, workforce development, consumer behavior with respect to the smart grid and safety issues.

Superstimulation in donor cows increases the number of cumulus-oocyte complexes (COC), but when compared to in vivo maturation, in vitro maturation results in only half as many blastocysts after prolonged in vitro culture. The objective of this study was to establish a superstimulation protocol that would produce a maximal number of competent COC for standard in vitro embryo production. During experiment 1, eight cyclic Holstein heifers were superstimulated with four doses of FSH. Half the heifers received an injection of LH 6 h before ovum pick-up (OPU). The COC were collected following OPU either 33 or 48 h following the last FSH injection (coasting period). During experiment 2, six cyclic Holstein heifers were superstimulated with six doses of FSH, and in half the heifers, LH was administered 6 h before OPU. The COC were collected following ultrasound-guided transvaginal aspiration of both ovaries 48 h after the last FSH injection (coasting period). The COC originating from follicles with a diameter of 5 mm or more (n = 180 for experiment 1 and 57 for experiment 2) were subjected to standard in vitro maturation, fertilization, and development. When animals were administered four doses of FSH, 48 h of coasting resulted in significantly more 5- to 10-mm follicles (P0.01) than 33 h of coasting. If a 33-h coasting period was used, administration of LH 6 h before OPU resulted in a significant increase in both percentage of blastocysts and embryo production rate at Days 7 and 8 (Por = 0.05) of in vitro culture. If a 48-h coasting period was used, LH injection did not affect the rates of blastocyst production. When donors were administered six doses of FSH with a 48-h coasting period, the highest results, although not significant (P0.08), were obtained when animals received LH 6 h before OPU, with 80% +/- 9% (mean +/- SEM) blastocysts and 0.8 +/- 0.09 embryo produced per COC retrieved per heifer at Day 8 of culture. Never has in vitro technology been so close to producing 100% developmentally competent COC.

Enucleated mouse zygotes receiving eight-cell nuclei rarely develop beyond the two-cell stage, whereas enucleated two-cell embryos with eight-cell nuclei develop to blastocysts, and a few develop to midgestation. In this study the function of eight-cell nuclei in either the zygote or two-cell recipient was assessed by monitoring several nuclear-dependent events. These included methionine uptake, qualitative changes in protein synthesis, the time of blastocoele formation, and changes in nuclear volume. Although enucleated zygotes with nuclei from eight-cell embryos did not develop past the two-cell stage and had abnormally low levels of methionine uptake, they did show a normal zygote-to-two-cell transition in the types of polypeptides synthesized. Enucleated two-cell embryos with eight-cell nuclei formed blastocysts on schedule with the recipient cell stage and reached levels of methionine uptake equivalent to control embryos. The types of proteins synthesized by two-cell embryos with eight-cell nuclei indicated that the nucleus was developing partly in accord with its own developmental program. Transplanted nuclei did not enlarge to acquire the volume of the recipient cell's nucleus in either the zygote or the two-cell recipient. These results indicate that the difference in development between zygotes and two-cell embryos (each with eight-cell nuclei) may be the result of a greater overlap of function between the two-cell and eight-cell stages, rather than the extent of nuclear reprogramming. Nuclear function was not completely normal in either type of embryo, which may explain their failure to develop to term.

In cows, protein synthesis is required for germinal vesicle breakdown (GVBD). This study examines more closely the need for protein synthesis and the nuclear changes in the bovine oocyte during 24 h of culture. Bovine oocytes with compact and complete cumulus were washed and incubated in groups of 10 for up to 24 h in SO-pd drops of TCM-199 supplemented with follicle-stimulating hormone (NIAMADD, 0.5 �.Lg/ml), luteinizing hormone (LH) NJAMADD, 5 �.tg/ml), estradiol-17fi (1 �.tg/ml), pyruvate (20 pM), and 10% heattreated fetal calf serum. Medium was overlaid with paraffin oil. Oocytes (n = 891) were fixed at the end of each 3-h interval from 0 to 24 h of culture, or at 24 h after addition of cycloheximide (10 pg/ml at 10 different times during maturation (0, 1, 2, 3, 6, 9, 12, 15, 18, 21 h; n = 175). At each time point, the chromosomal status of oocytes was evaluated, frequencies were computed, and the time spent on each step was determined. The germinal vesicle (GV) was present from 0 to 6.6 h, GVBD at 6.6 to 8.0 h, chromatin condensation at 8.0 to 10.3 h, metaphase I at 10.3 to 15.4 h, anaphase I at 15.4 to 16.6, telophase I at 16.6 to 18.0 h, and metaphase II at 18.0 to 24 h. Cycloheximide blocked oocyte maturation at GVBD, if added from 0 to 3 h; at chromatin condensation, 4fpresent from 6 to 24 h; and at metaphase 1, when present from 9 to 12 h. When cycloheximide was present from 12 to 24 h an increasing number of oocytes reached metaphase II (19% for 12 h, 36% for 15 h, 51% for 18 h, 90% for 21 h, 94% for 24 h), but many abnormalities were noted

Blastomeres from 2- to 32-cell bovine embryos were transferred to enucleated oocytes matured either in vivo or in vitro by micromanipulation and electrofusion. The percentage of donor cells fusing with the recipient oocytes was dependent on relative cell size or stage of development. Therefore, when smaller donor karyoplasts (17- to 32-cell vs. 2- to 8-cell) were transferred, the rate of fusion was significantly less (p less than 0.01). After fusion, nuclear transfer embryos were cultured either in vitro or in vivo (in a ligated ovine oviduct). Nuclear transfer embryos cultured in vitro developed to the 4- to 6-cell stage after 72 h (4-cell, 71%; 8-cell, 33%, 16-cell, 33%; p less than 0.30), whereas nuclear transfer embryos cultured in vivo developed to the morula or blastocyst stage (2- to 8-cell, 11.7%; 9- to 16-cell, 16.0%; 17- to 32-cell, 8.3%; p greater than 0.30) after 4 or 5 days. Freshly ovulated oocytes (collected 36 h after the onset of estrus), when used as recipients, resulted in morula/blastocyst-stage embryos more often than in vitro-matured oocytes or in vivo-matured oocytes collected 48 h after the onset of estrus (20% vs. 7.8% and 6.7%, respectively; p less than 0.02). After in vivo culture, nuclear transfer embryos were mounted and fixed or transferred nonsurgically to the uteri of 6- to 8-day postestrus heifers. Seven pregnancies resulted from the transfer of 19 embryos into 13 heifers; 2 heifers completed pregnancy with the birth of live calves.(ABSTRACT TRUNCATED AT 250 WORDS)