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1.
Rev Sci Instrum ; 94(3): 031102, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-37012753

ABSTRACT

The Z machine is a current driver producing up to 30 MA in 100 ns that utilizes a wide range of diagnostics to assess accelerator performance and target behavior conduct experiments that use the Z target as a source of radiation or high pressures. We review the existing suite of diagnostic systems, including their locations and primary configurations. The diagnostics are grouped in the following categories: pulsed power diagnostics, x-ray power and energy, x-ray spectroscopy, x-ray imaging (including backlighting, power flow, and velocimetry), and nuclear detectors (including neutron activation). We will also briefly summarize the primary imaging detectors we use at Z: image plates, x-ray and visible film, microchannel plates, and the ultrafast x-ray imager. The Z shot produces a harsh environment that interferes with diagnostic operation and data retrieval. We term these detrimental processes "threats" of which only partial quantifications and precise sources are known. We summarize the threats and describe techniques utilized in many of the systems to reduce noise and backgrounds.

2.
J Phys Chem A ; 110(13): 4538-42, 2006 Apr 06.
Article in English | MEDLINE | ID: mdl-16571061

ABSTRACT

We have developed an efficient method for producing difunctional, bilateral nanospheres. A monolayer of nanoparticles was prepared followed by deposition of a thin layer of metal. By varying the base particle and metal deposited, bilateral nanoparticles were formed. The different regions of the nanoparticles were selectively functionalized with polymer linkers containing specific terminal groups, thereby creating bilateral, difunctional nanoparticles. Subsequent covalent cross-linking of different nanoparticles enabled the formation of stable architectures with programmed hierarchy and controlled chemical composition.


Subject(s)
Nanotechnology/methods , Nanotubes , Polyethylene Glycols/chemistry , Microscopy, Electron, Scanning , Molecular Structure , Nanotubes/chemistry , Nanotubes/ultrastructure , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
3.
J Reprod Fertil ; 84(1): 171-8, 1988 Sep.
Article in English | MEDLINE | ID: mdl-3184040

ABSTRACT

Embryos collected from donor ewes 2 days after oestrus were transferred to the oviducts of entire cyclic (Group EC), unilaterally ovariectomized and cyclic (Group UO), entire anoestrous (Group EA), and bilaterally ovariectomized (Group BO) ewes, and 4 h, 1, 3 or 5 days after transfer the oviducts and uteri were flushed to recover embryos. Ewes in Group BO were untreated or treated with regimens of progesterone and oestradiol designed to simulate ovarian secretion before, around the time of, and after oestrus in entire ewes. There were no differences in the proportions of transferred embryos that were recovered, or in their location (oviduct or uterus), between the two sides of Group UO ewes and they were similar to recovery rates and locations of embryos in Group EC ewes. At 3 days after transfer, 62% and 50%, respectively, of embryos recovered from ewes in Groups EC and UO were in the uterus and by 5 days the percentages had risen to 89% and 75%, respectively. With all treatment regimens fewer of the transferred embryos were recovered from Group BO ewes than from Group EC ewes and few were located in the uterus. In Group BO ewes low recovery rates, and failure of embryos to enter the uterus, appeared to be due to deficiencies in the treatment regimens rather than to effects of ovariectomy. Most embryos recovered from treated ewes in Group BO and those in Groups EC and UO showed apparently normal development (86% and 79%, respectively), while 65% and 75%, respectively, recovered from untreated Group BO and Group EA ewes had developed normally. Only 9 of 163 embryos recovered from the untreated Group BO and EA ewes were located in the uterus and 8 of the 9 had failed to develop normally. Clearly, the steroid hormone requirements for development in the oviducts are not critical, but this is not so for the uterus.


Subject(s)
Embryo Transfer , Fetal Death , Uterus/physiology , Animals , Fallopian Tubes/physiology , Female , Ovariectomy , Pregnancy , Sheep
4.
Theriogenology ; 29(5): 1149-53, 1988.
Article in English | MEDLINE | ID: mdl-16726438

ABSTRACT

Six fallow does were inseminated directly into the uterine horns 72 h (three does) or 78 h (three does) after the removal of progestagen intravaginal sponges. Three does were inseminated with fresh (two at 72 h and one at 78 h) or frozen-thawed (one at 72 h and two at 78 h) semen. The semen used had been collected by electroejaculation and had been stored for 2 yr in liquid nitrogen in a Tris, citric acid, glycerol diluent containing 2.25% egg yolk. Three does each produced a live fawn to insemination and all does had been inseminated 72 h after removal of sponges; two with fresh semen and one with frozen semen. The remaining three does failed to conceive to insemination, but did produce fawns to mating at a subsequent estrus.

5.
Aust J Biol Sci ; 41(1): 15-22, 1988.
Article in English | MEDLINE | ID: mdl-3077739

ABSTRACT

The ovariectomized ewe has been used to establish principles and procedures which have proved invaluable in controlled breeding in entire animals. Bioassays in the ovariectomized ewe, the end-point of oestrous behaviour, have been used to identify potent and rapidly metabolized progestagens which were subsequently used to control the time of oestrus and ovulation in cyclic ewes effectively, and to induce oestrus and ovulation in anoestrous ewes. Steroid hormone treatment of the ovariectomized ewe has been used to study relationships between the ovary and the pituitary-hypothalamic axis, to examine transport of embryos within the female tract and to establish the steroid hormone requirements of early pregnancy.


Subject(s)
Breeding , Ovariectomy/veterinary , Sheep , Anestrus/metabolism , Animals , Estrogens/physiology , Estrus/physiology , Female , Gonadal Steroid Hormones/physiology , Male , Ovulation Induction/veterinary , Pregnancy , Progesterone/physiology , Sexual Behavior, Animal
6.
Aust Vet J ; 62(7): 228-34, 1985 Jul.
Article in English | MEDLINE | ID: mdl-4051914

ABSTRACT

Five experiments involving 1,244 cows and heifers were carried out to investigate the factors which might influence the calving performance to fixed-time artificial insemination following intravaginal administration of progesterone (PRID) and intramuscular injection of pregnant mare serum gonadotrophin (PMSG). Factors examined were duration of PRID treatment, time of treatment after calving, time and dose PMSG and lactational status. Experiments 1, 2 and 3 were carried out on milked Friesian cows, experiment 4 on Friesian heifers and experiment 5 on suckled and dry Herefords. All cows were inseminated once with frozen/thawed semen 54 to 58 h or 46 to 50 h after completion of PRID treatment. Overall there was a progressive increase in calving rates with an increase in the duration of treatment from 12 to 14 to 16 days but there was little or no effect of time after calving (4 v 7 weeks) at which treatment was commenced. The poorer calving performance of cows treated for 12 to 14 days was associated with relatively high peripheral levels of plasma progesterone at the time of the PRID removal, suggesting the presence at the end of treatment of residual secretory luteal tissue. There was an effect on calving performance of PMSG given at the time of PRID removal but its effect varied according to the duration of PRID treatment. After 12 days treatments (experiments 1 and 5) PMSG had little effect, whereas after 14 days treatments, 0, 500 and 750 IU PMSG gave calving rates of 27%, 40% and 46% in experiment 2 and 5%, 24% and 38% in experiment 5.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Animal Husbandry , Gonadotropins, Equine/administration & dosage , Pregnancy, Animal/drug effects , Progesterone/administration & dosage , Animals , Cattle , Dose-Response Relationship, Drug , Drug Administration Schedule , Estradiol/administration & dosage , Estrus/drug effects , Female , Injections, Intramuscular , Insemination, Artificial/veterinary , Pregnancy , Progesterone/blood , Vagina/drug effects
7.
J Reprod Fertil ; 73(2): 353-9, 1985 Mar.
Article in English | MEDLINE | ID: mdl-4039363

ABSTRACT

The effects of treatment with intravaginal progesterone (PRID) oestradiol benzoate and cloprostenol at various stages of the oestrous cycle were examined in 2 experiments. In Exp. 1, PRIDs were inserted for 14 days commencing on Day 3, 10 or 17 of the oestrous cycle and half the animals in each group received 5 mg oestradiol benzoate at PRID insertion. Plasma samples were collected daily from the time of PRID insertion for 16 days, then every 4 days for a further 24 days. Samples were analysed for plasma progesterone concentration. In Exp. 2, heifers were treated on Day 10 as in Exp. 1, but half of each treatment group received 750 micrograms cloprostenol at PRID insertion. In Exp. 1, treatment with PRID alone appeared to inhibit endogenous progesterone production when treatment began on Day 3, but not when treatment began on Days 10 or 17. Treatment with oestradiol benzoate at the time of PRID insertion depressed progesterone levels, from about 2-5 days after injection. When treatment began on Day 10, the fall in progesterone levels after oestradiol benzoate was preceded by a marked rise in levels. In Exp. 2, treatment with cloprostenol markedly reduced peripheral concentrations of progesterone and also removed the effect of oestradiol. We suggest that oestradiol benzoate had a luteolytic effect, depressing luteal progesterone production when given on Days 3, 10 or 17 and that when given on Day 10 there was a transitory luteotrophic effect which preceded its luteolytic action.


Subject(s)
Cloprostenol/pharmacology , Corpus Luteum/metabolism , Estradiol/pharmacology , Progesterone/pharmacology , Prostaglandins F, Synthetic/pharmacology , Animals , Cattle , Corpus Luteum/drug effects , Estrus , Female , Pregnancy , Progesterone/administration & dosage , Progesterone/blood , Vagina
9.
J Reprod Fertil ; 68(1): 137-44, 1983 May.
Article in English | MEDLINE | ID: mdl-6188824

ABSTRACT

The secretion and synthesis of protein in vitro by explants of endometrium were examined in entire ewes during the first 10 days of the oestrous cycle and during an equivalent interval in ovariectomized ewes which received injections of oestradiol and progesterone. The schedule of steroid injections given was designed to simulate endogenous ovarian secretion of progesterone during the luteal phase before oestrus, of oestradiol around oestrus and of progesterone during the luteal phase after oestrus. The rate of protein synthesis and tissue RNA:DNA and protein:DNA ratios in intercaruncular and caruncular endometrium were generally higher in entire than in ovariectomized ewes. In ovariectomized ewes oestradiol increased these activities at 2-4 days after oestrus, whereas progesterone preceding oestradiol caused increases at oestrus, but not thereafter. In entire ewes and in ovariectomized ewes receiving the full steroid treatment regimen, protein secretion was high at oestrus and declined markedly during the next 4-6 days. In ovariectomized ewes not receiving progesterone before oestradiol, secretion increased between 4 and 6 days after oestrus, or during the equivalent stage of treatment in ewes which did not show oestrus. The omission of this progesterone did not modify secretion by caruncular endometrium. Oestradiol increased protein secretion by both tissues. The data suggest that progesterone given before oestradiol (or its equivalent in entire ewes) inhibits the secretion, at about 4-7 days after oestrus, of uterine proteins which may impair embryo development in ovariectomized ewes which do not receive this progesterone.


Subject(s)
Endometrium/metabolism , Protein Biosynthesis , Animals , Castration , DNA/biosynthesis , Endometrium/drug effects , Estradiol/pharmacology , Estrus , Female , In Vitro Techniques , Medroxyprogesterone/pharmacology , Pregnancy , Progesterone/pharmacology , RNA/biosynthesis , Sheep
10.
J Reprod Fertil ; 61(1): 79-82, 1981 Jan.
Article in English | MEDLINE | ID: mdl-7452629

ABSTRACT

Six nanny goats and 9 ewes were inseminated with Barbary semen and 4-5 days after insemination 16 hybrid embryos were recovered: 14 were transferred to ewes or nanny goats. Survival of embryos was monitored by return to service after transfer, peripheral plasma progesterone values and by examination at laparotomy. None of the Barbary ram x ewe embryos transferred to 4 ewes and 4 nanny goats or the Barbary ram x nanny goat embryos transferred to ewes survived. Of the 4 nanny goat recipients of Barbary rm x nanny goat embryos one had a resorbed fetus at 7 weeks after transfer, one was pregnant at 7 weeks but failed to produce a young and a third produced a healthy male 155 days after the transfer oestrus. The karyotype of the hybrid was 2n = 59XY, characterized by a single metacentric chromosome.


Subject(s)
Crosses, Genetic , Goats/genetics , Sheep/genetics , Animals , Embryo Transfer , Female , Fertilization , Hybridization, Genetic , Insemination, Artificial , Karyotyping/veterinary , Male , Pregnancy , Progesterone/blood
14.
Aust J Biol Sci ; 30(3): 225-8, 1977 Jun.
Article in English | MEDLINE | ID: mdl-562656

ABSTRACT

Ovariectomized ewes received injections designed to mimic to some extent oestradiol and progesterone secretion during early pregnancy (maintenance progesterone), during oestrus (oestrous oestradiol) and during the luteal phase of the previous cycle (priming progesterone). The animals were killed at times equivalent to 1, 4 or 7 days after oestrus in those animals which had received oestrous oestradiol. The level of soluble oestradiol and progesterone receptors in whole uterus, and [3H]oestradiol and [3H]progesterone metabolism by uterus minces were measured. Oestradiol receptor level was highest on day 1 in those animals receiving oestrous oestradiol with no significant effect at any stage of the inclusion or omission of priming or maintenance progesterone. Progesterone receptor level was also high on day 1 in those animals receiving oestrous oestradiol with high levels maintained to day 4. Again, inclusion of priming or maintenance progesterone was without effect. In animals not receiving oestrous oestradiol the level of both receptors was uniformly low. Metabolism of [3H]oestradiol was low and not affected by treatment. [3H]Progesterone metabolism, although more variable, was also low and not affected by treatment.


Subject(s)
Castration , Estradiol/metabolism , Progesterone/metabolism , Receptors, Estrogen/analysis , Receptors, Progesterone/analysis , Sheep/metabolism , Uterus/metabolism , Animals , Estradiol/pharmacology , Estrus , Female , Pregnancy , Progesterone/pharmacology , Uterus/analysis
16.
Aust J Biol Sci ; 29(5-6): 565-73, 1976 Dec.
Article in English | MEDLINE | ID: mdl-1023869

ABSTRACT

The hormonal regulation of metabolism in the genital tract and the development of embryos during early pregnancy in the ewe have been examined. Ovariectomized ewes received injections of maintenance progesterone, oestrous oestradiol and priming progesterone according to schedules designed to simulate endogenous ovarian secretion during early pregnancy, around the time of oestrus and during the luteal phase of the oestrous cycle immediately preceding oestrus. The survival and development of embryos was dependent upon the dose of maintenaince progesterone and the duration of treatment at the time of transfer, but changes in progesterone dose did not change endometrial protein or RNA metabolism on particular days. Both priming progesterone and oestrous oestradiol were required for normal embryo development. Priming progesterone and oestrous oestradiol each increased endometrial RNA/DNA ratios during early pregnancy. There were no interactions between priming progesterone and oestrous oestradiol, their effects being simply additive. Neither maintenance nor priming progesterone had any effect on protein and RNA metabolism in the oviduct. It is suggested that in the intact ewe oestrogen secreted at oestrus and progesterone secreted prior to oestrus play important roles in the establishment of a uterine environment suitable for the subsequent normal development of embryos.


Subject(s)
Embryo, Mammalian/physiology , Estradiol/pharmacology , Genitalia, Female/metabolism , Progesterone/pharmacology , Protein Biosynthesis , RNA/metabolism , Sheep/physiology , Animals , Castration , Endometrium/metabolism , Fallopian Tubes/metabolism , Female , Ovary/physiology , Pregnancy , Pregnancy, Animal/drug effects
19.
Aust J Biol Sci ; 29(3): 237-44, 1976 Jul.
Article in English | MEDLINE | ID: mdl-791228

ABSTRACT

The susceptibility of fertilized sheep ova and oocytes, with and without zonae pellucidae, to lysis by complement plus antibodies in antisera raised against sheep ovaries, oocytes and sperm was examined in vitro. The presence of the zona reduced the proportion of ova lysed (8% v. 57%) and a large proportion of ova with zonae continued development in culture following exposure to antisera. Antisera to ovary and to oocytes lysed a higher proportion of ova than did antisera to sperm (51 and 56% v. 29%). There was no effect of age of fertilized ova (day 2, 4, 6; day 0 = day of oestrus) on susceptibility to lysis. Fluorescein-labelled antibodies from high-titre antisera to ovary and oocytes traversed the zona and attached to blastomeres. Following absorption of the antibody conjugates with sheep serum, fluorescein staining of ova with intact zonae was confined to the zona, whereas with zona-free ova the blastomeres were stained. It appears that the zona may protect embryos from lytic antibodies and it is suggested that the zona may be important in protecting the embryo from immunological attack in vivo.


Subject(s)
Antibodies/analysis , Antigen-Antibody Reactions , Ovum/immunology , Sheep/immunology , Animals , Complement System Proteins , Female , Fluorescent Antibody Technique , Male , Oocytes/immunology , Ovary/immunology , Spermatozoa/immunology , Zona Pellucida/immunology
20.
Aust J Biol Sci ; 29(1-2): 125-9, 1976 Mar.
Article in English | MEDLINE | ID: mdl-962719

ABSTRACT

Goat embryos collected 5 and 7 days after mating, were cultured in vitro at 37 degrees C for 2 days, or stored at 5 degrees C for 1 or 2 days and then cultured for 2 days, or stored in liquid nitrogen (-196 degrees C) for 2-4 weeks and then cultured for 1 day. After culture some of the embryos were transferred to recipient does. Culture and storage was carried out in Dulbecco phosphate buffer enriched with 25% goat serum. 1M glycerol or 2M dimethylsulphoxide (DMSO) was added to the media used for frozen storage. Thirteen of 15 embryos cultured without prior storage showed apparently normal development in culture. Ten of the 13 were transferred and five kids were born. Twenty of 38 embryos stored at 5 degrees C developed in culture and six kids were born following the transfer of 17 embryos. Duration of storage at 5 degrees C had no marked effect upon subsequent development. Six of 48 frozen stored embryos developed in culture. All six were transferred and three kids were born.


Subject(s)
Embryo, Mammalian , Goats , Tissue Preservation , Animals , Animals, Newborn , Cold Temperature , Culture Techniques , Embryo Transfer , Female , Freezing , Pregnancy , Transplantation, Homologous
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