A review of current timed-AI (TAI) programs for beef and dairy cattle

PubMed Central

Colazo, Marcos G.; Mapletoft, Reuben J.

2014-01-01

This is a review of the physiology and endocrinology of the estrous cycle and how ovarian physiology can be manipulated and controlled for timed artificial insemination (TAI) in beef and dairy cattle. Estrus detection is required for artificial insemination (AI), but it is done poorly in dairy cattle and it is difficult in beef cattle. Protocols that synchronize follicle growth, corpus luteum regression and ovulation, allowing for TAI, result in improved reproductive performance, because all animals are inseminated whether they show estrus or not. As result, TAI programs have become an integral part of reproductive management in many dairy herds and offer beef producers the opportunity to incorporate AI into their herds. Gonadotropin-releasing hormone-based protocols are commonly used in North America for estrus synchronization as part of a TAI program. Protocols that increase pregnancy rates in lactating dairy cows and suckling beef cows have been developed. Protocols that improve pregnancy rates in heifers, acyclic beef cows, and resynchronized lactating dairy cows are also discussed. PMID:25082993

A review of current timed-AI (TAI) programs for beef and dairy cattle.

PubMed

Colazo, Marcos G; Mapletoft, Reuben J

2014-08-01

This is a review of the physiology and endocrinology of the estrous cycle and how ovarian physiology can be manipulated and controlled for timed artificial insemination (TAI) in beef and dairy cattle. Estrus detection is required for artificial insemination (AI), but it is done poorly in dairy cattle and it is difficult in beef cattle. Protocols that synchronize follicle growth, corpus luteum regression and ovulation, allowing for TAI, result in improved reproductive performance, because all animals are inseminated whether they show estrus or not. As result, TAI programs have become an integral part of reproductive management in many dairy herds and offer beef producers the opportunity to incorporate AI into their herds. Gonadotropin-releasing hormone-based protocols are commonly used in North America for estrus synchronization as part of a TAI program. Protocols that increase pregnancy rates in lactating dairy cows and suckling beef cows have been developed. Protocols that improve pregnancy rates in heifers, acyclic beef cows, and resynchronized lactating dairy cows are also discussed.

Effect of preovulatory follicle maturity on pregnancy establishment in cattle: the role of oocyte competence and the maternal environment

USDA-ARS?s Scientific Manuscript database

Reproductive technologies to synchronize estrus and ovulation in cattle have enhanced the ability to practically utilize artificial insemination to increase both genetic merit and reproductive management of beef and dairy herds. The ability to successfully synchronize a follicular wave and ovulation...

Supplementation with rumen-protected L-arginine-HCl increased fertility in sheep with synchronized estrus.

PubMed

de Chávez, Julio Agustín Ruiz; Guzmán, Adrian; Zamora-Gutiérrez, Diana; Mendoza, Germán David; Melgoza, Luz María; Montes, Sergio; Rosales-Torres, Ana María

2015-08-01

The aim of the present study was to evaluate the effects of L-arginine-HCl supplementation on ovulation rate, fertility, prolificacy, and serum VEGF concentrations in ewes with synchronized oestrus. Thirty Suffolk ewes with a mean body weight of 45 ± 3 kg and a mean body condition score (BCS) of 2.4 ± 0.28 were synchronized for estrus presentation with a progestin-containing sponge (20 mg Chronogest® CR) for 9 days plus PGF2-α (Lutalyse; Pfizer, USA) on day 7 after the insertion of the sponge. The ewes were divided into two groups; i.e., a control group (n = 15) that was fed on the native pasture (basal diet) and an L-arginine-HCl group (n = 15) that received 7.8 g of rumen-protected L-arginine-HCl from day 5 of the sponge insertion until day 25 after mating plus the basal diet. The L-arginine-HCl was administered daily via an esophageal probe between days 5 and 9 of the synchronization protocol and every third day subsequently. Blood samples were drawn from the jugular vein every 6 days throughout the entire experimental period. The results revealed that the L-arginine-HCl supplementation increased fertility during the synchronized estrus (P = 0.05). However, no effects were observed on the final BCS (P = 0.78), estrus presentation (P = 0.33), multiple ovulations (P = 0.24), prolificacy (P = 0.63), or serum VEGF concentration. In conclusion, L-arginine-HCl supplementation during the period used in this study increased fertility in sheep with synchronized estrus possibly due to improved embryo-fetal survival during early pregnancy.

Synchronization of ovulation and fixed time intrauterine insemination in ewes.

PubMed

Deligiannis, C; Valasi, I; Rekkas, C A; Goulas, P; Theodosiadou, E; Lainas, T; Amiridis, G S

2005-02-01

A novel method for oestrus-ovulation synchronization in sheep followed by fixed time insemination is presented herewith. Mature dry ewes (n = 28) of Karagouniko breed being at an unknown stage of the oestrous cycle, were used during the middle of breeding season. The treatment protocol consisted of an initial administration of a GnRH analogue followed 5 days later by a prostaglandin F2alpha injection. Thirty-six hours later a second GnRH injection was administered to synchronize ovulation, and laparoscopic intrauterine insemination was performed 12-14 h later. Three days after insemination, fertile rams were introduced into the flock twice daily and oestrus-mating detection was carried out. For progesterone (P(4)) determination, blood samples were collected on alternate days, starting 2 days before the first GnRH injection and continuing for 17 days after insemination. An additional sample was taken on the day of insemination. Pregnancy diagnosis was carried out by trans-abdominal ultrasonography. Fourteen ewes (50%) conceived at insemination and maintained pregnancy; from the remainder 14 ewes 10 became pregnant at natural service, while four, although they mated at least two to three times, failed to conceive. In response to the first GnRH, P(4) concentration increased at higher levels in ewes that conceived at AI compared with those that failed to conceive (47.54 and 22.44%, respectively; p < 0.05). Significant differences (p < 0.05) in mean P(4) concentration between pregnant and non-pregnant animals were detected 1 day before AI (0.17 +/- 0.06 and 0.26 +/- 0.14 ng/ml, respectively) on the day of AI (0.15 +/- 0.04 and 0.24 +/- 0.08 ng/ml, respectively) as well as 9 and 11 days thereafter (0.48 +/- 0.12 and 0.38 +/- 0.12 ng/ml; 0.68 +/- 0.14 and 0.50 +/- 0.18 ng/ml, respectively). These results indicate that using the proposed protocol, an acceptable conception rate can be achieved which could be further improved by modifying the time intervals between interventions.

Follicular dynamics, circulating progesterone, and fertility in Holstein cows synchronized with reused intravaginal progesterone implants that were sanitized by autoclave or chemical disinfection.

PubMed

Melo, L F; Monteiro, P L J; Nascimento, A B; Drum, J N; Spies, C; Prata, A B; Wiltbank, M C; Sartori, R

2018-04-01

This experiment aimed to compare circulating progesterone (P4), follicular dynamics, and fertility during reuse of intravaginal P4 implants that were sanitized by autoclave or chemical disinfection in lactating Holstein cows submitted to fixed-time artificial insemination (FTAI). For this, 123 primiparous and 226 multiparous cows from 2 farms, averaging (mean ± standard deviation) 163.9 ± 141.9 d in milk, 35.7 ± 11.3 kg of milk/d, and a body condition score of 2.9 ± 0.5, were enrolled in the study. Cows were randomly assigned to 1 of 2 treatments using a completely randomized design and each cow received a reused implant (1.9 g of P4; previously used for 8 d) that was either autoclaved (AUT; n = 177) or chemically disinfected (CHEM; n = 172) on d -10. Also on d -10, cows received 2 mg of estradiol benzoate and 100 μg of GnRH. On d -3, cows received 25 mg of dinoprost (PGF 2α ). A second PGF 2α was given on d -2, along with 1 mg of estradiol cypionate and P4 implant removal. Cows received FTAI on d 0. A subset of cows (n = 143) was evaluated by ultrasound on d -10, -8, -6, -3, -2, 0, and 5 to identify ovarian structures, and blood was sampled on d -10, -3, and -2 for P4 concentrations by RIA. Pregnancy diagnoses were performed at d 32 and 60. Statistical analyses was performed using PROC-MIXED for continuous variables and PROC-GLIMMIX of SAS 9.4 (SAS Institute Inc., Cary, NC) for binomial variables. The treatments did not differ in circulating P4 on d -10 or -3, but P4 was greater on d -2 in CHEM cows. Ovulation to the treatments on d -10 was associated with lower circulating P4 on d -10 (2.0 vs. 3.1 ng/mL) and resulted in greater P4 on d -3 (4.0 vs. 2.4 ng/mL) and more cows with a corpus luteum on d -3 (100 vs. 40%) than nonovulating cows. Cows that ovulated to d -10 treatments were more likely to have a synchronized new follicular wave (97.9 vs. 63.2%) and had an earlier wave emergence (1.9 vs. 2.6 d), resulting in less cows ovulating a persistent follicle (0.0 vs. 35.7%). Type of P4 implant, corpus luteum presence on d -10, and ovulation to d -10 treatments did not affect fertility (pregnancy per AI; P/AI). However, P/AI on farm A was greater than on farm B at 32 (40.8 vs. 27.8%) and 60 d (35.8 vs. 24.3%), independent of treatment. In conclusion, P4 implants with different P4 release patterns did not produce detectable differences in follicular dynamics, synchronization rate, or P/AI. Nevertheless, presence of corpus luteum or ovulation at the beginning of the FTAI protocol affected reproductive variables, such as timing and synchronization of follicular wave emergence, and size of the ovulatory follicle. Beyond that, more overall synchronized cows became pregnant to the FTAI protocol. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Clomiphene Stair-Step Protocol for Women With Polycystic Ovary Syndrome.

PubMed

Jones, Tiffanny; Ho, Jacqueline R; Gualtieri, Marc; Bruno-Gaston, Janet; Chung, Karine; Paulson, Richard J; Bendikson, Kristin A

2018-01-01

To compare time to ovulation, ovulation rates, and side effect profile of traditional and the stair-step protocol for ovulation induction using clomiphene citrate in women with polycystic ovary syndrome (PCOS). We performed a retrospective study of women seeking care for infertility with a diagnosis of PCOS at a university-based infertility clinic from July 2012 to July 2014. We included patients who were resistant to the initial starting dose of 50 mg clomiphene. The primary outcome was time to ovulation. Secondary outcomes included ovulation rates, clinical pregnancy rates, and mild and moderate-to-severe side effects based on dose. For the traditional protocol, higher doses of clomiphene were used each subsequent month if no ovulation occurred. For the stair-step protocol, higher doses of clomiphene were given 7 days after the last dose if no dominant follicles were seen on ultrasonography. Our study had 80% power to detect a 20% difference in ovulation. One hundred nine patients were included in the analysis with 66 (60.6%) in the traditional and 43 (39.4%) in the stair-step protocol. Age and body mass index were similar between groups. The time to ovulation was decreased in the stair-step protocol group compared with the traditional protocol group (23.1±0.9 days vs 47.5±6.3 days). Ovulation rates were increased in the stair-step group compared with the traditional group at 150 mg (16 [37%] vs 8 [12%], P=.004) and at 200 mg (9 [21%] vs 3 [5%], P=.01). Pregnancy rates were similar between groups once ovulation was achieved (12 [18.1%] vs 7 [16.3%], P=.08). The stair-step protocol had an increased incidence of mild side effects (vasomotor flushes, headaches, gastrointestinal disturbance, mastalgia, changes in mood; 18 [41%] vs 8 [12%]), but there was no difference in the incidence of severe side effects (headaches, visual disturbances). For women with PCOS, the stair-step clomiphene protocol is associated with decreased time to ovulation and increased ovulation rates at higher doses when compared with the traditional protocol.

Plasma oxidative stress biomarkers and progesterone profiles in a dairy cow diagnosed with an ovarian follicular cyst.

PubMed

Talukder, S; Ingenhoff, L; Kerrisk, K L; Celi, P

2014-01-01

This study was conducted to examine the oxidative stress biomarkers in a cow diagnosed with a follicular cyst in her left ovary. Progesterone (P4) and plasma oxidative stress status was measured in 13 Holstein cows after synchronization of oestrus with controlled internal drug release (CIDR) and prostaglandinF2α (PGF2α) protocol. The presence and size of ovarian structures were monitored by transrectal ultrasound at 4 hourly intervals. Of the 13 cows, 12 were monitored until ovulation was detected and recorded, whereas one cow failed to ovulate and developed a follicular cyst. Oxidative stress biomarkers; reactive oxygen metabolites (ROMs), biological antioxidant potential (BAP), oxidative stress index (OSI), glutathione (GSH), ceruloplasmin and advanced oxidation protein products (AOPP) were measured in the cystic cow and compared to those of the 12 ovulated cows and are referred to as higher or lower if they are outside the mean ± standard error of mean of those of ovulated cows. The cystic cow had lower ROMs and OSI between 36 and 84 h after PGF2α injection and at 9 h, from 36 to 60 h after PGF2α injection respectively. On the other hand, antioxidant (BAP and GSH) was higher in the cystic cow compared to her ovulated herd mates. The observed imbalance between oxidant and antioxidant might have disrupted the physiological events for ovulation to occur, leading to cystic ovarian disease.

Factors affecting the size of ovulatory follicles and conception rate in high-yielding dairy cows.

PubMed

Mokhtari, A; Kafi, M; Zamiri, M J; Akbari, R

2016-03-01

Two studies were designed to determine (1) the effects of Heatsynch and Ovsynch protocols versus spontaneous ovulation and (2) the effects of calving problems, clinical uterine infections, and clinical mastitis on the size of the ovulatory follicle, conception rate, and embryonic/fetal (E/F) death in high-yielding dairy cows. In study 1, cows without the history of calving problems, clinical uterine infections, and clinical mastitis were randomly allocated to either an Ovsynch (n = 45) or Heatsynch (n = 39) ovulation synchronization protocol or spontaneous ovulation (n = 43) groups. Blood samples were collected on the day of artificial insemination (AI) to measure progesterone (P4), estradiol-17β, and insulin-like growth factor 1 (IGF-1) and 7 days later to measure P4. Study 2 consisted of cows (n = 351) with or without the history of calving problems, clinical uterine infections, and clinical mastitis which were artificially inseminated after a 55-day voluntary waiting period. Transrectal ultrasonography was performed at the time of AI to measure the ovulatory follicle size and on Days 30 and 68 after AI to diagnose pregnancy in both studies. In study 1, the mean (±standard error of the mean) diameter of the ovulatory follicle was greater (P = 0.0005) and E/F mortality was lower (P = 0.007) for the spontaneous ovulation group compared with Ovsynch and Heatsynch groups. Serum concentration of P4 on Day 7 after AI was correlated with the size of the ovulatory follicle (P = 0.007). Conception rate at Days 30 and 68 was not significantly different between the three experimental groups in study 1. Cows with serum IGF-1 concentrations greater than 55 ng/mL at AI had significantly higher Day 68 conception rate (50% vs. 24%) and lower E/F death (16.6% vs. 40%) compared to cows with serum IGF-1 concentrations lower than 56 ng/mL at AI. The conception rate on Days 30 and 68 for follicles of 10 to 14 mm in diameter (34% and 21.8%) was significantly lower than follicles of 14.1 to 19 mm in diameter (60% and 50%), respectively (P < 0.05). In study 2, the ovulatory follicle in cows with clinical uterine infections was smaller than that in cows without clinical uterine infections (16.4 vs. 17.1 mm; P = 0.04). In conclusion, the size of the ovulatory follicle is affected by ovulation synchronizing protocols and postpartum clinical uterine infections. In addition, cows with higher serum IGF-1 concentrations on the day of AI had higher Day 68 conception rate and lower E/F death. Copyright © 2016 Elsevier Inc. All rights reserved.

Ultrasonographic and endocrine evaluation of three regimes for oestrus and ovulation synchronization for sheep in the subtropics.

PubMed

Ali, A; Hayder, M; Saifelnaser, E O H

2009-12-01

This study aimed to evaluate three regimes for oestrus and ovulation synchronization in Farafra ewes in the subtropics. During autumn, 43 ewes were assigned to (i) controlled internal drug releasing (CIDR)-eCG group, treated with CIDR for 12 days and eCG at insert withdrawal, n=13; (ii) PGF2alpha-PGF2alpha group, treated with two PGF2alpha injections at 11 days interval, n=14; and (iii) GnRH-PGF2alpha-GnRH group, treated with GnRH, followed 5 days later with PGF2alpha and 24 h later with a second GnRH, n=16. Oestrus-mating detection was carried out at 4 h intervals starting on day 0 [the day of CIDR withdrawal (CIDR-eCG group), the day of second PGF2alpha treatment (PGF2alpha-PGF2alpha group) and the day of PGF2alpha treatment (GnRH-PGF2alpha-GnRH group)]. Ovarian dynamics was monitored by ultrasound every 12 h beginning on day 0 and continued for 4 days. Blood samples were obtained daily for progesterone (P4) and oestradiol 17beta (E2) estimation starting on day 0 and continued for 4 days. The obtained results showed that, oestrus expression, ovulation and conception were greater (p<0.05) in CIDR-eCG and PGF2alpha-PGF2alpha groups than in GnRH-PGF2alpha-GnRH group. All ewes of PGF2alpha-PGF2alpha group presented, on day of second PGF2alpha injection with mature CL (P4>2.0 ng/ml), compared to 42.9% in GnRH-PGF2alpha-GnRH group (p=0.01). The peak of oestrus occurred 32-52, 48-60 and 28-96 h after the end of treatment in CIDR-eCG, PGF2alpha-PGF2alpha and GnRH-PGF2alpha-GnRH groups, respectively. Ovulation started 48 h after treatment in all groups and extended for 24, 36 and 48 h for CIDR-eCG, PGF2alpha-PGF2alpha and GnRH-PGF2alpha-GnRH groups, respectively. Results demonstrated that oestrus and ovulation synchronization could be efficiently achieved in Farafra ewes using either CIDR-eCG or PGF2alpha-PGF2alpha regimes; however, the GnRH-PGF2alpha-GnRH treatment induced a more spread oestrus and ovulation that may make the protocol inadequate for timed artificial insemination.

Timed artificial insemination should be performed early when used norgestomet ear implants are applied for synchronizing ovulation in beef heifers.

PubMed

Sá Filho, M F; Penteado, L; Siqueira, G R; Soares, J G; Mendanha, M F; Macedo, G G; Baruselli, P S

2013-10-01

The present study evaluated the effect of the type of norgestomet ear implant (new vs. used) on the ovarian follicular response (experiment 1) and pregnancy per artificial insemination (AI) (P/AI; experiment 2) of beef heifers subjected to an estradiol plus progestin timed artificial insemination (TAI) program. In experiment 1, 57 cyclic beef heifers were randomly assigned to one of two groups according to the type (new or previously used for 9 days) of norgestomet ear (NORG) implant. At the time of NORG implant insertion, the heifers were treated with 2 mg of intramuscular estradiol benzoate. Eight days later, the NORG implants were removed, and the heifers received an intramuscular administration of 150 μg of d-cloprostenol, 300 IU of equine chorionic gonadotropin, and 0.5 mg of estradiol cypionate. The heifers had their ovaries scanned every 12 hours from the time of NORG implant removal to 96 hours after verifying the occurrence and timing of ovulation. No difference (P = 0.89) was observed in the ovulation rates between the two treatments (new = 80.0%; 24/30 vs. used = 81.5%; 22/27). However, the heifers treated with a used NORG implant had (P = 0.04) higher proportion (36.4%; 8/22) of early ovulation (between 36 and 48 hours after NORG implant removal) compared with the heifers treated with a new NORG implant (8.3%; 2/24). In experiment 2, at the beginning of the synchronization protocol, 416 beef heifers were randomly assigned into two groups, as described in the experiment 1. Two days after the NORG implant removal, the heifers were reassigned to be inseminated at 48 or 54 hours after NORG implant removal. There was an interaction (P = 0.03) between the type of NORG implant and the timing of TAI on P/AI. The timing of insemination only had an effect (P = 0.02) on the P/AI when the heifers were treated with a used NORG implant [(TAI 54 hours = 41.9% (44/105) vs. TAI 48 hours = 58.6% (58/99)]. In conclusion, beef heifers synchronized with a used NORG implant plus estradiol exhibited a higher proportion of earlier ovulations, and TAI in these heifers should be performed 48 hours after removal of used NORG implants. Copyright © 2013 Elsevier Inc. All rights reserved.

The relationship between external auditory canal temperature and onset of estrus and ovulation in beef heifers.

PubMed

Randi, Federico; McDonald, Michael; Duffy, Pat; Kelly, Alan K; Lonergan, Patrick

2018-04-01

The aim of this study was to evaluate the relationship of body temperature fluctuations, as measured by external auditory canal temperature, to the onset of estrus and ovulation. Beef heifers (n = 44, mean age 23.5 ± 0.4 months, mean weight 603.3 ± 5.7 kg) were fitted with a Boviminder ® ear tag 2 weeks before the start of the estrous synchronization protocol to allow acclimatization. The device recorded the temperature, accurate to 0.01° Fahrenheit, every 10 min and transmitted the data via a base station over the internet where it could be accessed remotely. The estrous cycles of all heifers were synchronized using an 8-day progesterone-based synchronization program; on day 0 a PRID was inserted in conjunction with an injection of GnRH, and PGF2α was administered the day before PRID removal. Heifers were checked for signs of estrus at 4-h intervals (i.e., 6 times per day) commencing 24 h after PRID withdrawal. Beginning 12 h after the onset of estrus, the ovaries were ultrasound scanned at 4-h intervals to determine the time of ovulation. Body temperature was recorded every 10 min and averaged to hourly means for the following 4 periods relative to the detected oestrus onset (=Time 0): Period I: -48 h to -7 h, Period II: -6 h to +6 h, Period III +7 h to ovulation, and Period IV: ovulation to 48 h post ovulation. Data were analysed using a Mixed Model ANOVA in SAS in a completely randomized design to observe effects of induced estrus on external auditory canal temperature. The mean (±SD) interval from removal of the PRID to onset of estrus activity was 46.6 ± 14.7 h. The mean duration of estrus was 16.0 ± 5.67 h and the mean interval from estrus onset to ovulation was 27.9 ± 7.68 h. Highest temperatures (100.95 ± 0.03 °F) were observed in Period II around estrus onset, whereas lowest temperatures were observed in the 48 h preceding estrus onset (100.28 ± 0.03 °F; Period I) and around ovulation (100.30 ± 0.2 °F; Period III)(P < .001). Indeed, around the time of estrus onset (Period II) mean temperature was 0.66 °F (P < .001) higher compared with Period I. Diurnal temperature rhythms were similar (P > .10) before (Period I) and after oestrus (Period III). In conclusion, a significant elevation in external auditory canal temperature was associated with estrus in beef heifers and was followed by a decline in temperature leading up to ovulation approximately 28 h later. Future studies are required to assess pregnancy rates following AI based on changes in external auditory canal temperature. Copyright © 2018 Elsevier Inc. All rights reserved.

Fertility after ovarian follicular wave synchronization and fixed-time natural mating compared to random natural mating in dromedary camels (Camelus dromedarius).

PubMed

Nagy, P; Juhasz, J

2012-06-01

The objective of the study was to compare the efficiency of two ovarian follicular wave synchronization protocols coupled with fixed-time natural mating with that of random mating in dromedary camels. Dromedaries were assigned randomly to one of the three treatment groups. Group 1 animals (RM; n = 46) were mated randomly. Group 2 camels (1×GnRH-FTM; n = 46) were given a GnRH analog (Buserelin, 20 μg/animal, i.v.; Receptal, Intervet, Holland) at random, then were mated 14 days later. In Group 3 animals (2×GnRH-FTM; n = 41), random GnRH analog was followed by repeated GnRH injection 14 days later and fixed-time natural mating on Day 28. Transrectal examination and ultrasonography were performed at weekly intervals to evaluate ovarian follicular status, diagnose ovulation and pregnancy. Blood samples were collected for progesterone determination by ELISA to confirm ovulation and pregnancy. All female dromedaries were assigned randomly to one of thirteen fertile bulls and were bred once on Days 1, 14 and 28 in Groups 1-3, respectively. Ovarian follicular status and ovulation rate was similar among groups at the start of the study. Seventy-five of the 133 dromedaries (56.4%) ovulated after random natural mating or random GnRH treatment. Mean length of mating was 386 ± 17.8 (±SEM) seconds. There was no significant difference in mating time among groups and in pregnancy rate among dromedary bulls. In Group 3 (2×GnRH-FTM), ovarian follicular status before mating (P < 0.05), ovulation rate (n = 37, 90.2%, P < 0.001) and pregnancy rate at 21 and 60 days (PR 21 days n = 22, 53.7% and PR 60 days n = 19, 46.3%, P < 0.05) were greater compared to random natural mating (Group 1: OR n = 25, 54.3%, PR 21 days n = 13, 28.3% and PR 60 days n = 12, 26.1%). In Group 2 dromedaries (1×GnRH-FTM), treatment tended to improve follicular status before mating, ovulation rate (n = 34, 73.9%) and pregnancy rate at 21 and 60 days (PR 21 days n = 21, 45.7% and PR 60 days n = 16, 34.8%), but the effect was not significant compared to random natural mating. In conclusion, this is the first study demonstrating that favorable pregnancy rate can be achieved following ovarian follicular wave synchronization with repeated GnRH analog and fixed-time natural mating at 14 days intervals in dromedary camels. Copyright © 2012 Elsevier B.V. All rights reserved.

Concentrations of steroid hormones, estrous, ovarian and reproductive responses in sheep estrous synchronized with different prostaglandin-based protocols.

PubMed

Fierro, S; Viñoles, C; Olivera-Muzante, J

2016-04-01

To determine estrous, ovarian and reproductive responses after different prostaglandin (PG)-based protocols, ewes were assigned to groups PG10, PG12, PG14 or PG16 (twoPG injections administered 10, 12, 14 or 16 days apart; respectively). Experiment I (n=132) was conducted to evaluate the estrous response, ovulation rate (OR), conception and fertility. Experiment II (n=24) was conducted to evaluate ovarian follicle growth, steroid concentrations and the interval from the second PG injection to estrus (PG-estrus) and ovulation (PG-ovulation). Estrous response was less with the PG16 (P<0.05) treatment, and the extent of estrous synchrony was greater with the PG10 and PG12 treatments. Ovarian follicle growth and the intervals for the variables PG-estrus, PG-ovulation and OR were similar among groups (P>0.05). From 8 to 4 days before estrus, progesterone (P4) concentrations were greater for the PG14 and PG16 than for the PG10 and PG12 (P<0.05) groups. There were more days where concentrations of P4 were above 3.18 nmol/L with the PG14 and PG16 than PG10 and PG12 (P<0.05) treatments. Use of the PG14 and PG16 treatments resulted in greater estradiol (E2) at estrus and 12h later than use of the PG10 and PG12 treatments. A positive correlation was observed between the duration of the luteal phase and maximum E2 concentrations, and between duration of the luteal phase and days with E2 concentrations above 10 pmol/L. Conception and fertility were greater with use of the PG14 compared with PG10 and PG12 (P<0.05) treatments. The administration of two PG injections 10, 12, 14 or 16 days apart resulted in different durations of the luteal phase that were positively associated with E2 concentrations and the reproductive outcome. The shorter luteal phases were associated with greater synchrony in time of estrus. The intervals for the variables PG-estrus, PG-ovulation and OR were similar among groups. Copyright © 2016 Elsevier B.V. All rights reserved.

Seasonality, estrous cycle characterization, estrus synchronization, semen cryopreservation, and artificial insemination in the Pacific white-sided dolphin (Lagenorhynchus obliquidens).

PubMed

Robeck, T R; Steinman, K J; Greenwell, M; Ramirez, K; Van Bonn, W; Yoshioka, M; Katsumata, E; Dalton, L; Osborn, S; O'Brien, J K

2009-08-01

The reproductive physiology of the Pacific white-sided dolphin, Lagenorhynchus obliquidens, was characterized to facilitate the development of artificial insemination (AI) using cryopreserved spermatozoa. Specific objectives were to: 1) describe reproductive seasonality of the Pacific white sided dolphins; 2) describe urinary LH and ovarian steroid metabolites during the estrous cycle; 3) correlate LH and ovarian steroidal metabolite patterns to ultrasound-monitored follicular growth and ovulation; and 4) assess the efficacy of synchronizing estrus, sperm collection/cryopreservation, and intrauterine insemination. Ovulations (64%, n=37) and conceptions (83%, n=18) occurred from August to October. Peak mean serum testosterone (24 ng/ml), cross-sectional testicular area (41.6 cm(2)), and sperm concentration (144.3 x 10(7) sperm/ml) occurred in July, August, and September respectively. Spermatozoa were only found in ejaculates from July to October. Estrous cycles (n=22) were 31 d long and were comprised of a 10 d follicular and 21 d luteal phase. Ovulation occurred 31.2 h after the onset of the LH surge and 19.3 h after the LH peak. Follicular diameter and circumference within 12 h of ovulation were 1.52 and 4.66 cm respectively. Estrus synchronization attempts with altrenogest resulted in 17 (22%) ovulatory cycles with ovulation occurring 21 d post-altrenogest. Ten AI attempts using cryopreserved semen resulted in five pregnancies (50%). The mean gestation length was 356 days (range 348-367). These data provide new information on the Pacific white-sided dolphin's reproductive physiology and collectively enabled the first application of AI in this species.

Efficacy of four synchronization protocols on the estrus behavior and conception in native Korean cattle (Hanwoo).

PubMed

Lee, Myeung-Sik; Rahman, Md Saidur; Kwon, Woo-Sung; Chung, Hak-Jae; Yang, Boh-Suk; Pang, Myung-Geol

2013-11-01

Ineffective estrus detection is the foremost limiting factor in the fertility of farmed cattle worldwide. Failure to detect estrus or erroneous diagnosis of estrus results in great economic losses in Korea each year. This study was carried out in order to comprehensively describe the estrus behaviors and conception rates of different estrus synchronization protocols applied to 40 cycling native Korean cattle (Hanwoo). The cows were grouped into four (n = 10) and treated with the following protocols: (1) Day -15: controlled intravaginal drug-releasing device (CIDR) for 12 days; Day -5: prostaglandin F2α (PGF2α), (2) ovulation synchronization (OVS): Day -15: GnRH; Day -6: PGF2α; Day -4: GnRH, (3) Day -15: progesterone-releasing intravaginal device for 12 days; Day -5: PGF2α; and (4) Day -15: PGF2α; Day -4: PGF2α. Artificial insemination was performed 12 hours after the detection of estrus using frozen-thawed semen. Estrus signs were compared using a charge-coupled device camera (CCDC) and a control method (direct visual observation). The pregnancy of the cows was determined by transrectal ultrasonography at Days 25 to 30 postinsemination. The results indicated that the day of estrus return was significantly earlier using the CCDC method compared with direct visualization (P < 0.05). Mounting of other cows was the most predominant sign of estrus among the flock (P < 0.05), as analyzed using the CCDC. In the OVS group, a lower rate of mounting was observed than in the other three groups. Moreover, significantly fewer estrus behaviors were noticed in the OVS protocol group (P < 0.05). Both first service conception and overall conception rates were significantly higher (P < 0.05) in the CIDR and OVS treatment groups. In conclusion, the CIDR and OVS protocols appear to be the best practice for the synchronization of estrus for reproductive competence through the CCDC in Hanwoo cows. However, CIDR has a practical advantage over OVS with respect to estrus detection. Copyright © 2013 Elsevier Inc. All rights reserved.

Effect of serum paraoxonase-1 (PON1) activity on follicular development and pregnancy rate in cattle.

PubMed

Castro, Natália A; Pfeifer, Luiz F M; Andrade, Jéssica S; Rincón, Joao A A; Pegoraro, Ligia M Cantarelli; Schneider, Augusto

2018-01-01

Paraoxonase-1 (PON1) activity has been associated with improvement in ovarian function in early postpartum dairy cows and improved in vitro embryo development. The aim of the current study was to evaluate the potential association among PON1 activity and follicular growth, diameter of the preovulatory follicle and pregnancy per artificial insemination (AI) service in cattle. In Experiment 1, cows (n=33) were subjected to an estradiol-progesterone based protocol to control time of ovulation. Starting on Day 8 of the protocol, follicular growth and serum PON1 activity were monitored. Cows were separated according to the occurrence of ovulation into two groups: Ovulatory (Ov; n=22) and Anovulatory (Anov; n=11). The serum activity of PON1 was not different between Ov and Anov cows (P=0.94). In addition, using a regression model there was no effect of serum PON1 activity on the diameter of dominant follicle (r 2 =0.00; P=0.99). In Experiment 2, cows (n=193) were submitted to the same hormonal protocol as in Experiment 1. On the day of the timed artificial insemination (TAI), the diameter of dominant follicle was evaluated and blood samples were collected for analysis of PON1 activity. According to the serum PON1 activity, cows were divided into three groups: Low (<70U/mL), Medium (70-90U/mL) or High (>90U/mL) PON1 activity. The overall pregnancy rate was 62.7% (121/193), with no difference among PON1 activity groups. Additionally, using a regression model there was no effect of serum PON1 activity on the diameter of the preovulatory follicle (r 2 =0.03; P=0.65) and pregnancy rate (r 2 =0.005; P=0.94). The results of this study indicate that there is no effect of serum PON1 activity on the diameter of preovulatory follicle or establishment of pregnancy in cows submitted to time of ovulation synchronization protocols. Copyright © 2017 Elsevier B.V. All rights reserved.

Protected fatty acid supplementation during estrus synchronization treatment on reproductive parameters of dairy goats.

PubMed

Oliveira, Juliana Dos Santos Kuhner; Fonseca, Jeferson Ferreira da; Souza-Fabjan, Joanna Maria Gonçalves; Esteves, Luciana Vieira; Feres, Luiz Fernando Rodrigues; Rodrigues, Carla Aparecida Florentino; Torres Filho, Rodolpho de Almeida; de Oliveira, Juliana; Brandão, Felipe Zandonadi

2017-02-01

This study evaluated the effect of the protected fatty acid inclusion during estrus synchronization on reproductive parameters. Goats (n = 32) received progestagen sponges for 6 days and 200 IU equine chorionic gonadotropin and 30 µg d-cloprostenol were given on Day 5. No difference was found among control (C), 1% protected fatty acid inclusion (C + 1%) or 4% protected fatty acid inclusion (C + 4%) groups, respectively, in estrus (100.0, 100.0 or 90.9%), estrus duration (31.6 ± 12.3; 43.2 ± 12.9 or 40.8 ± 14.1 h), animals ovulating (100.0, 90.0 or 100.0%) or ovulation rate (1.3 ± 0.5; 1.1 ± 0.3 or 1.2 ± 0.4). The interval from sponge removal to ovulation and from estrus to ovulation, respectively, were shorter for C + 4% (45.2 ± 8.0 h; 18.3 ± 11.0 h) compared with C (56.3 ± 12.6 h; 30.6 ± 10.5 h) or C + 1% (57.7 ± 8.7 h; 30.3 ± 11.1 h). The average ovulatory follicle diameter was smaller for C + 4% (6.2 ± 0.7 mm) than C (7.5 ± 0.8 mm), but similar to C + 1% (7.0 ± 1.5 mm). Insulin, insulin-like growth factor 1, glucose and progesterone concentrations were similar among groups. The inclusion of protected fatty acid during synchronization treatment promoted no benefits on ovulation rate, but 4% anticipated the ovulation time. © 2016 Japanese Society of Animal Science.

Effects of estrus synchronization using Matrix® followed by treatment with the GnRH agonist triptorelin to control ovulation in mature gilts.

PubMed

Knox, R V; Webel, S K; Swanson, M; Johnston, M E; Kraeling, R R

2017-10-01

Estrus and ovulation responses in Matrix-treated gilts may affect ovulation synchrony in response to triptorelin. In experiment 1, estrus and ovulation measures at 12h intervals after last Matrix feeding (LMF) were analyzed. For the 398 gilts that displayed estrus, 87.4% were detected on Days 6-8 after LMF. Duration of estrus was 24-60h for 85.6% of gilts and negatively correlated with interval from LMF to estrus (r=-0.53, P<0.0001). The estrus to ovulation interval was positively correlated with duration of estrus (r=0.61, P<0.0001). In experiment 2, gilts (n=96) received intravaginal treatment with 2mL of gel containing placebo (Control) at 96h, 200μg of triptorelin at 96h (TRP96), 120h (TRP120) or 144h (TRP144) after LMF. Estrus measures did not differ (P>0.10) among treatments. The proportion of gilts ovulating 32-56h after treatment was greater for TRP120 and TRP144 (P<0.01) compared to other treatments. The treatment to ovulation intervals for all triptorelin treatments were shorter (P<0.001) than Control. In experiment 3, gilts (n=86) received placebo (Control), 100μg (TRP100), 200μg (TRP200), or 400μg (TRP400) of triptorelin at 120h after LMF. There was no effect of treatment (P>0.10) on estrus or on interval from LMF to estrus. The proportion of gilts ovulating by 40, 48 and 56h after treatment increased (P<0.05) with triptorelin compared to Control. Our results indicate that gilts receiving 100-400μg of triptorelin at 120h after LMF had the greatest ovulation synchrony 24-48h following treatment. These studies provide important information for developing a procedure for a single insemination in synchronized gilts. Copyright © 2017 Elsevier B.V. All rights reserved.

Recent advances in the synchronization of estrus and ovulation in dairy cows.

PubMed

Macmillan, Keith L

2010-01-01

Synchronization programs have become standard components in the current breeding management of cows in the dairy herds of most dairy industries. Many are based on protocols that allow timed inseminations (TAI) so as to circumvent the practical difficulties associated with estrus detection. These difficulties are exacerbated in modern herds of high producing cows either because of increasing herd size in which individual animal monitoring is difficult and often subjective, or because small intensively managed herds are milked in robotic systems that minimize animal: staff interactions. Additional reasons arise from high producing cows having less obvious symptoms of estrus, partly because of housing systems combined with intensive feeding and milking, partly because of higher metabolic clearance rates of reproductive hormones like estradiol and partly because of the increasing prevalence of prolonged post-partum anestrus and reproductive tract pathology. The most recently developed programs include protocols for resynchronization following first or subsequent inseminations. These re-synchronization protocols may involve selected forms of hormonal intervention during the diestrous and pro-estrous periods following TAI, or following pregnancy diagnosis by ultrasound from 28 days after TAI. The latter form of re-synchronization has become increasingly important with the recognition that late embryonic/early foetal death has become a major factor compromising the reproductive performance of high producing Holstein cows in many dairy industries. Although cows detected in estrus without any hormonal treatment before insemination have higher conception rates than those inseminated following synchronization and TAI, the low detection rates combined with embryonic death means that intervals from calving to conception (days open) are usually less when synchronization programs have been successfully implemented. One of the significant factors affecting a program's success is the compliance rate that may sometimes be less than 70%. Almost all programs involve strategically timed injections of prostaglandin F2alpha (PGF) and gonadotropin releasing hormone (GnRH). Injections of an estradiol ester and progesterone supplementation per vaginum may be included in some programs. The basic program is the "Ovsynch" regimen. Numerous variations have been tested and developed. Many involve increasingly complex protocols that increase the risk of non-compliance, none has consistently achieved conception rates that exceed 40% and few have reduced the incidence of embryonic death. These synchronization programs are the best that are currently available. They have not been able to overcome the consequences of lowered fertility associated with high levels of milk yield, forms of nutrition and environmental factors like heat stress that have profound effects on the physiology and metabolism of the high producing dairy cow.

Synchronization of ovulation and fertility in weaned sows treated with intravaginal triptorelin is influenced by timing of administration and follicle size.

PubMed

Knox, R V; Willenburg, K L; Rodriguez-Zas, S L; Greger, D L; Hafs, H D; Swanson, M E

2011-01-15

A 100 μg dose of triptorelin was tested for synchronizing ovulation in sows. In Experiment 1, conducted in April through June, sows (n = 125) were assigned to Control (untreated), TG-96 (Triptorelin Gel (TG) given intravaginally at 96 h post-weaning), or TG-E (given intravaginally at estrus). To optimize AI timing, sows were inseminated at 2 and 26 h after estrus for Control and TG-E and at 8 and 32 h following TG-96. Ovulation by 48 h post-treatment tended to be affected by treatment (P = 0.08) and more (P < 0.05) TG-96 sows ovulated (57.9%) compared to Controls (34.2%), but TG-E (45.1%) did not differ (P > 0.10). Duration of estrus was reduced (P < 0.005) in TG-96 (51 h) and TG-E (58 h) compared to Controls (65 h). There was no treatment effect on farrowing rate (71%) or total born (10.4). Average follicle size <6.5 mm at 96 h after weaning was associated with reduced (P < 0.01) estrus, ovulation and farrowing rate. Experiment 2 was conducted in August through September using 503 weaned sows. The TG-96 treatment reduced duration of estrus (P = 0.03), but treatment did not affect estrus expression, farrowing rate or total pigs born. In conclusion, use of a 100 μg dose of triptorelin intravaginally at 96 h or at estrus advanced ovulation and when used with timed insemination, resulted in similar farrowing rates and litter sizes comparable to sows mated based on estrus. However, ovulation induction and timed AI success may benefit from an approach that ensures sows have adequate follicle development at time of treatment. Copyright © 2011 Elsevier Inc. All rights reserved.

Timing of sperm penetration, pronuclear formation, pronuclear DNA synthesis, and first cleavage in naturally ovulated mouse eggs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krishna, M.; Generoso, W.M.

1977-11-01

Timing of development of naturally ovulated mouse eggs from sperm penetration to first cleavage, including that of DNA synthesis, was established. In an attempt to limit variability, partial synchronization of ovulation was accomplished by shortening the length of the dark period to five hours, and partial synchronization of sperm entry was attempted by mating the females soon after the ovulated eggs reached the ampulla and by limiting the period at which mating could occur to only 20 minutes. Evidence of sperm penetration (presence of one or more sperm in perivitelline space or inside the vitellus) was found beginning 1.75 hoursmore » after the end of the mating period. Pronuclei were formed three to four hours after sperm entry. Pronuclear DNA synthesis began about eight hours postmating, 3.25 to 4.5 hours after pronuclear formation, or about 6.25 to 8.5 hours after sperm entry; it was completed in almost all zygotes by 16 hours postmating. The first completed cleavage division was found 17 to 18 hours postmating, and almost all eggs had cleaved by 20 hours.« less

Induction of an LH surge and ovulation by buserelin (as Receptal) allows breeding of weaned sows with a single fixed-time insemination.

PubMed

Driancourt, M A; Cox, P; Rubion, S; Harnois-Milon, G; Kemp, B; Soede, N M

2013-09-01

The aim of this study was to demonstrate successful breeding of sows with a single fixed-time insemination following ovulation induction by buserelin, a GnRH analogue. In a first step, the optimal dose of buserelin (6, 10, or 16 μg) injected at 77 hours after weaning was determined in weaned sows (N = 15, 11, and 12, respectively) using its ability to induce an LH surge of similar magnitude as in control sows (N = 15) and induce ovulation. In 29/38 treated sows (76%), ovulation was induced and synchronized between 32 and 44 hours after injection, and the proportion of females ovulating during this time window was similar between groups at 73%, 73%, and 83% (6, 10, or 16 μg, respectively). Interestingly, whereas ovulation of 100% multiparous sows was induced and synchronized in the 32 to 44 hours posttreatment time window, successful induction was achieved in a lower proportion of primiparous sows (50%, 50%, and 67% following 6, 10, or 16 μg, respectively), the dose effect being nonsignificant. The magnitude of the LH surge was similar between control and treated sows, irrespective of the buserelin dose injected. Neither ovulation rate nor the number of good embryos on Day 5 postovulation differed between groups. Interestingly, the frequency of follicular cysts at slaughter was significantly affected by treatment (P < 0.05), being minimal and maximal in sows treated with 10 or 6 μg buserelin, respectively. In a second step, 419 sows from commercial herds in Spain, Germany, and France were randomly allocated to a control or treated group. The control sows were inseminated twice 12 ± 4 hours apart once estrus was detected. Treated sows received 10 μg buserelin at 86 ± 3 hours after weaning and were inseminated once 30 to 33 hours later. Farrowing rate of treated sows (87%, 166/192) was similar to that of control sows (84.5%, 169/200). Litter size was also similar between treated and control sows (13.6 ± 3.8 vs. 13.7 ± 3.2). In multiparous sows, neither duration of lactation nor magnitude of the fat loss during lactation significantly affected treatment effects. It is concluded that ovulation of weaned multiparous sows can be tightly synchronized by buserelin (10 μg) administration at 86 hours postweaning. This allows breeding once at a fixed time following buserelin injection while maintaining reproductive performance at a level similar to that of sows bred twice during estrus. Copyright © 2013 Elsevier Inc. All rights reserved.

Uterine artery flow velocity waveform, arterial flow indices, follicular dynamics, and sex hormones during preovulatory period in synchronized ovulatory cycle of Bos indicus beef cows.

PubMed

Moonmanee, Tossapol; Navanukraw, Chainarong; Yama, Punnawut; Jitjumnong, Jakree

2018-03-01

A greater understanding of the uterine artery's (UtA) biology is essential to the increase in female reproductive abilities. The UtA flow velocity waveform, blood flow volume (BFV), pulsatility and resistance indices (PI and RI), blood flow velocities, dynamics of the dominant follicle (DF), and estradiol (E2) and progesterone (P4) levels in an induced ovulatory cycle were evaluated in Thai native cattle. Twenty cows were induced with synchronized ovulation through a P4-releasing device, from Day -9 to Day -4, concurrent with the administration of two doses of a gonadotropin-releasing hormone on Day -9 and Day -1, and two doses of prostaglandin F 2α on Day -4 and 8 h later. Day 0 was designated as the day of ovulation. The cows underwent Doppler sonographic determination and blood collection from Day -4 to Day 0. The cows were classified in the non-ovulating (n = 5) and ovulating groups (n = 15). The ovulating cows presented higher BFV values, blood flow velocities, DF growth rates, and E2 levels; yet lower PI values and P4 concentrations, than those of the non-ovulating cows. The BFV values and the blood flow velocities were greater, but the RI and PI values were lower in the ovulatory side UtA than in the contraovulatory side UtA. The BFV values were positively correlated with blood flow velocities, DF growth rates and E2 concentrations in the ovulating cows; confirming the importance of UtA blood flow, follicular growth, and E2-vasodilation during preovulatory phase in the induced ovulatory cycle of Bos indicus beef cows. Copyright © 2018 Society for Biology of Reproduction & the Institute of Animal Reproduction and Food Research of Polish Academy of Sciences in Olsztyn. Published by Elsevier B.V. All rights reserved.

Oestrous synchronization, ovarian superovulation and intraspecific transfers from a closed breeding colony of inbred SLA miniature pigs.

PubMed

Arlaud, J J; Baker, L; Williams, R L; French, A J

2010-12-01

The inbred SLA miniature pig is a unique animal model developed for organ transplantation studies and pre-clinical experimental purposes. Reported oestrous synchronization and superovulation treatments were examined in two SLA haplotypes (AA and DD) to allow collection of embryos for both practical embryo transfer and experimental technologies from a closed breeding colony. Pre-puberal miniature pigs were poor responders to oestrous synchronization treatments, while post-puberal sows were equivalent to commercial sows. Following superovulation, the ovulation number (corpora .hemorrhagica) was higher (p < 0.05) in the cycling sows when compared with non-cycling sows. Ovulations were equivalent to commercial pre-puberal gilts and non-cycling sows (p > 0.05). No difference in ovulation number between haplotypes was observed, which differs from the previous report (DD>AA). Collection of zygotes for pronuclear injection was the highest in the non-cycling post-puberal miniature pig group (p < 0.05), although significantly lower when compared with the commercial pig treatment groups (p < 0.05). The incidence of cystic endometrial hyperplasia in our colony was equivalent to rates observed in commercial pigs. Pronuclear visualization following centrifugation was the highest in the non-cycling miniature sow group and approximates to about 25% of ovulations and about half the rate observed in the commercial pigs (50%). Miniature pig embryos transferred between SLA haplotypes and transfer of DD embryos to commercial pigs resulted in live births at a higher efficiency than previously reported. This study demonstrates the feasibility of undertaking assisted reproductive technologies in a closed breeding colony of inbred SLA miniature pigs without compromise to the breeding programmes. © 2009 Blackwell Verlag GmbH.

Successful induction of oestrus, ovulation and pregnancy in adult ewes and ewe lambs out of the breeding season using a GnRH+progesterone oestrus synchronisation protocol.

PubMed

Martinez, M F; McLeod, B; Tattersfield, G; Smaill, B; Quirke, L D; Juengel, J L

2015-04-01

A series of experiments was designed to assess the effect of a treatment protocol (U-synch) for inducing oestrus and ovulation out of the breeding season in adult ewes and ewe lambs. The protocol consisted of a 7-day treatment with an intravaginal progesterone-releasing device (IPRD), administration of GnRH at IPRD insertion on Day 0, and equine chorionic gonadotropin (eCG) and prostaglandin F2α at IPRD removal on Day 7. In Experiment 1, 50 or 100 μg GnRH were sufficient to induce ovulation at the beginning of the protocol in 3/9 and 4/9 ewes, respectively; while the resulting proportion of sheep ovulating after the treatment protocol was 88.9% and 77.8% in ewes initially treated with 50 or 100 μg GnRH, respectively. In Experiment 2, the proportion of Romney-cross ewe lambs ovulating was greater (P<0.0001) in the U-synch group (95.4%) than in the untreated Control group (3.2%). In Experiment 3, pregnancy rates of Dorset-cross sheep in the U-synch (60.7%) and Standard (12-day IPRD and eCG treatment; 56.5%) groups were greater (P=0.01) than in the untreated Control group (43.4%). The incidence of twin pregnancies was greater (P=0.005) in the U-synch group than in the Control group. A 7-day IPRD treatment including GnRH treatment at device insertion and eCG treatment at device removal induced oestrus and ovulation during the non-breeding season in a high proportion of mature ewes and ewe lambs. High pregnancy rates to natural mating, with a low rate of triplet pregnancies, were also observed. Copyright © 2015 Elsevier B.V. All rights reserved.

Effects of altering the dose and timing of triptorelin when given as an intravaginal gel for advancing and synchronizing ovulation in weaned sows.

PubMed

Knox, R V; Taibl, J N; Breen, S M; Swanson, M E; Webel, S K

2014-08-01

Previous studies have shown that triptorelin gel (TG) given intravaginally in gel form is effective for advancing the time of ovulation in weaned sows. Three experiments were performed to determine the effects of altering the dose and timing of administration of intravaginal TG for advancing and synchronizing ovulation in weaned sows. In all experiments, estrus was detected twice or three times daily and ultrasound was performed to determine ovulation at 8-hour intervals. In experiment 1, sows (n = 131) received intravaginal gel containing 0 (Placebo), 25, 100, or 200 μg of TG at 96 hours after weaning and sows were inseminated on each day of standing estrus. Wean-to-estrus interval and duration of estrus were correlated (P < 0.0001) with estrus duration longer in TG (P < 0.05) compared with Placebo. More sows ovulated (P < 0.001) by 48 hours after treatment with 200 (81%), 100 (64%), and 25 μg (63%) of TG compared with Placebo (42%). The farrowing rate and total pigs born did not differ (P > 0.10). In experiment 2, sows (n = 126) received 200 μg of TG at 72, 84, or 96 hours after weaning or were untreated (Control-96). Sows receiving TG were inseminated once 24 to 28 hours after treatment. Control-96 sows were inseminated on each day of standing estrus. Wean-to-estrus interval was not affected by treatment, but wean-to-ovulation interval was reduced (P < 0.05) by TG-72 and TG-84 compared with TG-96 and Control-96. More sows ovulated 40 hours after treatment (P < 0.001) with TG-72 (56.5%) and TG-84 (32.2%) compared with TG-96 and Control-96 (13%) and for all TG treatments 48 hours after treatment (64%) compared with Control-96 (34%, P < 0.05). The farrowing rate was lower (P < 0.05) for sows assigned to TG-72 and TG-84 compared with TG-96 and Control-96, whereas the number of liveborn pigs did not differ (P > 0.10). In experiment 3, sows (n = 113) were assigned to receive no treatment (Control), intravaginal gel alone (Placebo), or 200 μg of TG given intravaginally (OvuGel) at 96 hours after weaning. Wean-to-estrus interval did not differ, but the duration of estrus tended (P < 0.10) to be reduced with OvuGel compared with the other treatments. More sows ovulated (P < 0.001) by 48 hours after OvuGel treatment (79.1%) compared with Control (46.4%) and Placebo (37.9%) and by 56 hours (P < 0.05). The farrowing rate and the number of liveborn pigs did not differ among treatments. The results of these studies indicate that 200 μg of TG given intravaginally at 96 hours after weaning (OvuGel) synchronizes ovulation and results in fertility similar to Controls. Copyright © 2014 Elsevier Inc. All rights reserved.

A new classification of a preovulatory oocyte maturation stage suitable for the synchronization of ovulation in controlled reproduction of Eurasian perch Perca fluviatilis L.

PubMed

Zarski, Daniel; Bokor, Zoltán; Kotrik, László; Urbanyi, Béla; Horváth, Akos; Targońska, Katarzyna; Krejszeff, Sławomir; Palińska, Katarzyna; Kucharczyk, Dariusz

2011-11-01

To improve controlled reproduction of Eurasian perch Perca fluviatilis, the criteria for the evaluation of final oocyte maturation stages were revised. The new classification covers six preovulatory maturational stages (I -VI) from the end of vitellogenesis to germinal vesicle breakdown (GVBD) and was based on macroscopic changes of preovulatory oocytes (position of the germinal vesicle, GVBD, oil droplets coalescence). The observation was performed during out-of-season artificial reproduction with the use of a single hCG injection (500 IU/kg). The classification was subsequently verified with the controlled reproduction of wild female perch with the use of hormonal stimulation (500 IU hCG/kg of body weight at 12°C). The females were at different maturational stages and constituted respective experimental groups (I-VI). During the experiment, ovulation appeared to be considerably synchronized within particular groups. Statistical differences in latency time (time between hormonal treatment and ovulation) were found between experimental groups (mean latency time: 110, 92, 68, 49, 29 and 18 h in groups representing VI, V, IV, III, II and I stage of the proposed classification, respectively). The proposed classification and the results presented in the study allowed for effective synchronisation of ovulation. The use of our new oocyte maturation classification may positively influence the effectiveness of Eurasian perch production.

JSAR Innovative Technology Award. Development of ovulation synchronization and fixed time artificial insemination in dairy cows.

PubMed

Yamada, Kyoji

2005-04-01

Recently, reproductive management has become more difficult as a result of increased herd size. Problems with missing estrous signs and decrease in conception rate by artificial insemination (AI) performed at wrong timing have caused low AI conception rates. In 1995, ovulation synchronization and fixed-time AI (Ovsynch/TAI) was developed in the USA as a new reproductive technology, which was accepted as an useful reproductive management tool in many countries. However, no information on the use of Ovsynch/TAI was available in Japan. It was, therefore, warranted to show the ovulation rate and conception rate after Ovsynch/TAI using gonadotropin releasing hormone analogue (GnRH-A, fertirelin acetate) and prostaglandin F2alpha (PGF2alpha)-THAM, both were commercially available in this country. The conception rate after Ovsynch/TAI has been known to vary among different herds and individuals. Investigation and analysis of factors affecting the conception rate was also warranted to improve the conception rate. A series of experiments were carried out to establish Ovsynch/TAI using domestically produced GnRH-A and PGF2alpha and to study factors affecting conception rate after Ovsynch protocol. Ovsynch using 100 microg GnRH-A and 25 mg PGF2alpha were observed using ultrasonography. As a result, a high synchronization rate of ovulation at 16 to 20 h after the second GnRH injection was confirmed. The conception rate after Ovsynch/TAI was compared in 87 cows with the conception rate after AI at estrus induced by PGF2alpha (139 cows). Conception rate after Ovsynch/TAI was higher than the figure after AI at induced estrus (59.1% vs 20.9%, P<0.05). The dose of GnRH-A was also studied and a practical dose of GnRH-A was found to be 50 microg per cow. To clarify some factors affecting the conception rate after Ovsynch/TAI, 1,558 cows were investigated for the state of their ovaries, days after calving, parity, season, ovarian cyclicity postpartum and nutritional state at the day of Ovsynch. The overall conception rate after Ovsynch/TAI was 51.5%. Fifty-six cows (3.6%) showed estrus at 6 to 7 d after the first injection of GnRH-A. The conception rate after Ovsynch/TAI was low in cows that were 40 to 60 d postpartum, those in their 5th lactation or more, those bred in July to August, and those recovering ovarian cyclicity later than 56 d postpartum. The conception rate after Ovsynch/TAI was high in cows in which body condition score (BCS) was 3.75 at dry period and 3.0 at the day of Ovsynch. In conclusion, Ovsynch/TAI is an effective tool for the reproductive management of dairy cows. A steady and sufficient conception rate after Ovsynch/TAI could be expected by taking the factors affecting the conception rate into the consideration.

Ovarian and endocrine responses in tropical sheep treated with reduced doses of cloprostenol.

PubMed

Contreras-Solis, Ignacio; Vasquez, B; Diaz, T; Letelier, C; Lopez-Sebastian, A; Gonzalez-Bulnes, A

2009-09-01

The present study aimed to assess the efficacy of reduced doses of cloprostenol for synchronizing estrus and ovulation in hair sheep. With the aim to evaluate the luteolytic activity of reduced cloprostenol doses, a first experiment was performed using a relatively large (group H: 126 microg; n=8), medium (group M: 68.25 microg; n=6) and small (group L: 38.5 microg; n=6) cloprostenol dose. Luteolysis was assessed at Days 3 and 6 after injection (Day 0) by progesterone concentrations (P(4)) and transrectal ultrasonography (US). In Experiment 2, sheep were randomly assigned to the same three doses to evaluate a protocol for estrous synchronization using two injections administered 9 days apart. A third trial was performed with ewes treated (9 days apart) with the large dose (H=126 microg; n=12) and with a small dose adjusted for facilitating volume management (LA=43.75 microg; n=12). Presence of estrous cycling was determined in all the ewes by US and P(4) assay, at Days -9, -6, -2, 0 (Day of second cloprostenol injection), 8 and 11. Bleeding and US were done every 4h from 16 h of the beginning of the estrus during the third trial to assess the preovulatory LH surge and timing of ovulation. Additionally, blood samples were drawn at Days 0, 1, 2 and 3 to assess estradiol (Experiments 2 and 3) and P(4) (Experiment 2) concentrations during the ovarian follicular phase. In all experiments, percentage of animals showing luteolysis, preovulatory follicular dynamics and function and percentage of ewes showing behavioral estrus in response to treatment was similar among groups. Timing of estrus for group H was earlier than group L (28.6+/-1.8h compared with 37.1+/-2.4h; P<0.05). In the third trial, the preovulatory LH peak was higher in the LA group than group H, in terms of maximum mean concentration during the surge (27.7+/-1.8 ng/mL compared with 21.3+/-2.2 ng/mL; P<0.05) and area under the curve (AUC; 183.4+/-12.7 ng/mL compared with 127.7+/-10.9 ng/mL; P<0.01). However, timing of ovulation was similar for H and LA groups. Thereafter, ovulation rate and luteal function at Day 11 were similar. Current results demonstrate that reduced doses of cloprostenol may be applied in a practical manner for reproductive management of sheep, with the additional advantage of reducing treatment costs.

Response of anestrous ewes to the ram effect after follicular wave synchronization with a single dose of estradiol-17beta.

PubMed

Ungerfeld, Rodolfo; Dago, Ana L; Rubianes, Edgardo; Forsberg, Mats

2004-01-01

Anestrous ewes respond to the introduction of rams with either an ovulation within 2-3 days that may be followed by luteal phases of normal or short length, with delayed ovulations (5-6 days later), or with the luteinization of follicles. The aim of this work was to study the relationship between the growth status of the largest follicle present when rams are introduced and the type of ovarian response in non-treated ewes and in ewes treated with estradiol-17beta before ram introduction. Thirteen anestrous Corriedale ewes were divided into 2 groups: E2 (n = 7) and C (n = 6). The E2 ewes received a single dose of 50 microg estradiol-17beta 5 days before the introduction of the rams to synchronize the onset of their follicle waves, while C ewes remained untreated. When the rams were introduced, all E2 ewes had the largest follicle in a growing stage in contrast with the C ewes (3 out of 6; P < 0.05). Five C and 4 E2 ewes ovulated after the introduction of the rams (Day 3.4 +/- 0.4 for C vs. 4.8 +/- 0.3 for E2 ewes, respectively, P < 0.05). Only one ewe from each group developed a normal luteal phase: 4 C and 3 E2 ewes had short luteal phases. One C ewe and 2 E2 ewes had short luteal phases originating from follicles that did not ovulate. After the first luteal phase, all ewes returned to anesirus without a second ovulation or luteal phase. The remaining E2 ewe did not ovulate or show any changes in progesterone serum concentrations. We conclude that the growth status of the largest follicle alone does not determine the ovarian responding pattern of anestrous ewes to the ram effect.

Ovarian responses and pregnancy rate with previously used intravaginal progesterone releasing devices for fixed-time artificial insemination in sheep.

PubMed

Vilariño, M; Rubianes, E; Menchaca, A

2013-01-01

The objective was to determine serum progesterone concentrations, ovarian responses, and pregnancy rate in sheep inseminated following a short-term protocol (6 days of treatment) with a previously used controlled internal drug release-G (CIDR-G) device. In experiment 1, 30 ewes were put on a short-term protocol using a CIDR-G of first use (new devices, N = 10), second use (previously used for 6 days, N = 10), or third use (previously used twice for 6 days, N = 10). All ewes were given prostaglandin F(2α) (10 mg dinoprost) and eCG (300 IU) im at device withdrawal. Mean serum progesterone concentrations were greater for ewes treated with new versus reused devices (P < 0.05), but there were no significant effects on ovarian follicular development, namely: proportion of ewes that reached ovulation/treated ewes (8/10, 9/10, and 10/10); day of emergence of the ovulatory follicle (2.9 ± 1.8, 1.8 ± 2.4, and 2.5 ± 1.1 days after CIDR-G insertion); and lifespan of the ovulatory follicle (5.4 ± 1.8, 6.5 ± 2.2, and 5.6 ± 1.0 days) for devices of first, second, and third use, respectively. The proportion of ewes that ovulated from a new follicle emerging after CIDR-G insertion was 100% (10/10) with new devices, and 77.8% (7/9) and 80% (8/10) with devices used two and three times, respectively (P = not significant). In experiment 2, ewes (N = 319) received the short-term protocol as in experiment 1, using CIDR-G of first or third use (N = 158 and N = 161, respectively) for 6 days, with prostaglandin F(2α) and eCG given im at device withdrawal. Intrauterine (laparoscopy) fixed-time AI with fresh semen (100 × 10(6) sperm) was done 52 to 57 hours after device withdrawal. Pregnancy rates were 80.4% (127/158) and 71.4% (115/161) for devices of first and third use, respectively (P = 0.06). We concluded that the CIDR-G with short-term protocol was effective for estrous synchronization and ovulation, with lower serum progesterone concentrations for reused devices. Three times used CIDR-G yielded a pregnancy rate >70%, which tended to be lower than that obtained with new devices, adding evidence of the detrimental effect of low serum progesterone concentrations on fertility in sheep. Copyright © 2013 Elsevier Inc. All rights reserved.

21 CFR 522.850 - Estradiol valerate and norgestomet in combination.

Code of Federal Regulations, 2011 CFR

2011-04-01

.... (c) Conditions of use—(1) Amount. One implant and 2 milliliters of injection at time of implantation. (2) Indications for use. For synchronization of estrus/ovulation in cycling beef cattle and non...

21 CFR 522.850 - Estradiol valerate and norgestomet in combination.

Code of Federal Regulations, 2014 CFR

2014-04-01

.... (c) Conditions of use—(1) Amount. One implant and 2 milliliters of injection at time of implantation. (2) Indications for use. For synchronization of estrus/ovulation in cycling beef cattle and non...

21 CFR 522.850 - Estradiol valerate and norgestomet in combination.

Code of Federal Regulations, 2010 CFR

2010-04-01

.... (c) Conditions of use—(1) Amount. One implant and 2 milliliters of injection at time of implantation. (2) Indications for use. For synchronization of estrus/ovulation in cycling beef cattle and non...

21 CFR 522.850 - Estradiol valerate and norgestomet in combination.

Code of Federal Regulations, 2013 CFR

2013-04-01

.... (c) Conditions of use—(1) Amount. One implant and 2 milliliters of injection at time of implantation. (2) Indications for use. For synchronization of estrus/ovulation in cycling beef cattle and non...

21 CFR 522.850 - Estradiol valerate and norgestomet in combination.

Code of Federal Regulations, 2012 CFR

2012-04-01

.... (c) Conditions of use—(1) Amount. One implant and 2 milliliters of injection at time of implantation. (2) Indications for use. For synchronization of estrus/ovulation in cycling beef cattle and non...

Effects of different five-day progesterone-based fixed-time AI protocols on follicular/luteal dynamics and fertility in dairy cows

PubMed Central

GARCIA-ISPIERTO, Irina; LÓPEZ-GATIUS, Fernando

2014-01-01

This study compares in two experiments the responses of lactating dairy cows to four different progesterone-based protocols for fixed-time artificial insemination (FTAI) in terms of their effects on follicular/luteal dynamics and fertility. The protocols consisted of a progesterone intravaginal device fitted for five days, along with the administration of different combinations of gonadotropin releasing hormone, equine chorionic gonadotropin and a single or double dose (24 h apart) of prostaglandin F2α. In Experiment I, the data were derived from 232 lactating cows. Binary logistic regression identified no effects of treatment on ovulation failure or multiple ovulation 10 days post artificial insemination (AI). Based on the odds ratio, the likelihood of ovulation failure was lower (by a factor of 0.1) in cows showing at least one corpus luteum (CL) upon treatment than in cows lacking a CL; repeat breeders (> 3 AI) and cows with multiple CLs at treatment showed lower (by a factor of 0.44) and higher (by a factor of 9.0) risks of multiple ovulation, respectively, than the remaining animals. In Experiment II, the data were derived from 5173 AIs. The independent variable treatment failed to affect the conception rate 28–34 days post AI, twin pregnancy or early fetal loss 58–64 days post AI. The results of this study demonstrate the efficacy of 5-day progesterone-based protocols for FTAI. All four protocols examined were able to induce ovulation in both cyclic and non-cyclic animals so that FTAI returned a similar pregnancy rate to spontaneous estrus. Our results suggest that the ovarian response and fertility resulting from each treatment are due more to the effect of ovarian structures at treatment than to the different combinations of hormones investigated. PMID:25196275

Estrus synchronization and artificial insemination of hair sheep ewes in the tropics.

PubMed

Godfrey, R W; Collins, J R; Hensley, E L; Wheaton, J E

1999-04-01

Hair sheep ewes (St. Croix White and Barbados Blackbelly) were used to evaluate 3 methods of estrus synchronization for use with transcervical artificial insemination (TAI). To synchronize estrus, ewes (n = 18) were treated with PGF2alpha (15 mg, im) 10 d apart, with controlled internal drug release (CIDR) devices containing 300 mg progesterone for 12 d (n = 18), or with intravaginal sponges containing 500 mg progesterone for 12 d (n = 18). On the day of the second PGF2alpha injection or at CIDR or sponge removal, sterile rams were placed with the ewes. Jugular blood samples were collected from the ewes at 6-h intervals until the time of ovulation, and daily for 16 d after estrus (Day 0). Plasma was harvested and stored at -20 degrees C until LH, and progesterone concentrations were determined by RIA. There was no difference (P>0.10) in time to estrus among the CIDR-, PGF2alpha- or sponge-treated ewes. All of the ewes in the CIDR group and 94.4% of the sponge treated ewes exhibited estrus by 36 h after ram introduction, while only 72.2% of PGF2alpha-treated ewes showed signs of estrus by this time (P<0.06). The time from ram introduction to ovulation was not different (P>0.10) among the CIDR-, PGF2alpha- or sponge-treated ewes. The time to the preovulatory LH surge was similar (P>0.10) among CIDR, PGF2alpha and sponge treated ewes. Progesterone levels through Day 16 after the synchronized estrus were not different (P>0.10) among treatment groups. Hair sheep ewes (n = 23) were synchronized using PGF2alpha and bred by TAI using frozen-thawed semen 48 h after the second injection. The conception rate to TAI was 2/23 (8.7%) and produced 3 ram lambs. In a subsequent trial, 17 ewes were synchronized with CIDR devices and bred by TAI using frozen-thawed semen 48 h after CIDR removal, resulting in a conception rate of 52.9% (9/17). It is possible to synchronize estrus in hair sheep using either CIDRs, sponges or PGF2alpha. Even though there were no significant differences in the timing of ovulation or the LH surge among the treatment groups, a higher conception rate was achieved in ewes synchronized with CIDR devices during the second trial. This may reflect an increase in the skill level of the TAI technician.

Clinical relevance of pre-ovulatory follicular temperature in heat-stressed lactating dairy cows.

PubMed

López-Gatius, F; Hunter, Rhf

2017-06-01

Temperature gradients in female reproductive tissues seem to influence the success of key processes such as ovulation and fertilization. The objective of this study was to investigate whether pre-ovulatory follicles are cooler than neighbouring uterine tissue and deep rectal temperatures in lactating dairy cows under heat stress conditions. Temperatures within the pre-ovulatory follicle, on the uterine adjacent surface and 20 cm deep within rectum, were measured using fine thermistor probes within 45 min after sunrise (dawn). Cows were selected from synchronized groups for fixed-time insemination during the warm period of the year. Five cows under direct sun radiation and 11 cows in the shade were included in the study. None of the cows in the sun area ovulated within 24 hr, whereas 10 of the 11 cows in the sun area ovulated. Four of the 10 ovulating cows became pregnant. In the ovulating cows, follicular temperatures were 0.74 and 1.54°C significantly cooler than uterine surface and rectal temperatures, respectively, whereas temperatures in the uterine area were 0.80°C significantly cooler than rectal temperatures. No significant differences among temperatures were found in non-ovulating cows. Follicular size was similar for ovulating and non-ovulating cows. Environmental temperatures in the shade area were 6.4°C significantly lower than those in the sun area. Results of this study indicate that pre-ovulatory follicles are cooler than neighbouring uterine tissue and deep rectal temperatures and those temperature gradients were not found in cows suffering ovulation failure. © 2017 Blackwell Verlag GmbH.

[Comparison of Alarelin and Triptorelin in the long-protocol ovulation induction in in vitro fertilization and embryo transfer].

PubMed

Duan, Jin-Liang; Jiang, Yuan-Hua; Liu, Ying; Zeng, Qiong-Fang; Huang, Ya-Dan

2010-07-01

To compare the pituitary down-regulatory effects of the two gonadotropin-releasing hormone agonists Alarelin and Triptorelin in the long protocol of ovulation induction in in vitro fertilization and embryo transfer (IVF-ET). We included in this study 122 patients aged 24-39 years treated by IVF-ET for secondary infertility, with 10-20 pre-antral follicles and obstruction of the fallopian tube. Seventy-eight of them received Alarelin, and the other 44 Triptorelin. Comparative analyses were made on the pituitary down-regulatory effects of the two gonadotropin-releasing hormone agonists and the clinical outcomes of IVF-ET. No premature LH surge and ovulation, nor severe hyperovarian stimulation syndrome was found in either group. There were no significant differences between the two groups in the mean dose and duration of gonodatropin treatment, the numbers of oocytes retrieved, mature oocytes and top-quality embryos, and the rates of 2PN, multi-sperm fertilization, cleavage, embryo transfer, embryo implantation, clinical pregnancy and early miscarriage (P > 0.05), but the rate of cancelled cycles was significantly higher in the Triptorelin than in the Alarelin group (P < 0.05). Alarelin and Triptorelin can achieve similar pituitary down-regulatory effects and clinical outcomes in IVF-ET when used in the long protocol of ovulation induction.

Strategies to overcome seasonal anestrus in water buffalo.

PubMed

de Carvalho, Nelcio Antonio Tonizza; Soares, Julia Gleyci; Baruselli, Pietro Sampaio

2016-07-01

Reproductive seasonality in buffalo (Bubalus bubalis) is characterized by behavioral, endocrine, and reproductive changes that occur over distinct periods of the year. During the nonbreeding season (spring and summer), the greater light-dark ratio (long days) suppresses estrus behavior and the occurrence of ovulation. Anestrous buffaloes have insufficient pulsatile of LH to support the final stages of follicular development, and subsequently, estrus behavior and ovulation do not occur, limiting reproductive efficiency, especially in artificial insemination (AI) programs. A number of therapeutic strategies designed to synchronize follicular wave emergence and ovulation have allowed for the use of AI throughout the year, overcoming seasonal anestrus in buffalo. These therapies also improve reproductive performance by increasing the service rate and pregnancy per AI in buffalo herds, regardless of reproductive seasonality. Copyright © 2016 Elsevier Inc. All rights reserved.

A proportional integral estimator-based clock synchronization protocol for wireless sensor networks.

PubMed

Yang, Wenlun; Fu, Minyue

2017-11-01

Clock synchronization is an issue of vital importance in applications of WSNs. This paper proposes a proportional integral estimator-based protocol (EBP) to achieve clock synchronization for wireless sensor networks. As each local clock skew gradually drifts, synchronization accuracy will decline over time. Compared with existing consensus-based approaches, the proposed synchronization protocol improves synchronization accuracy under time-varying clock skews. Moreover, by restricting synchronization error of clock skew into a relative small quantity, it could reduce periodic re-synchronization frequencies. At last, a pseudo-synchronous implementation for skew compensation is introduced as synchronous protocol is unrealistic in practice. Numerical simulations are shown to illustrate the performance of the proposed protocol. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

Short-term nutritional treatments grazing legumes or feeding concentrates increase prolificacy in Corriedale ewes.

PubMed

Viñoles, C; Meikle, A; Martin, G B

2009-07-01

We tested whether short periods of increased nutrition will improve ovulation rate and prolificacy, irrespective of the method used to synchronise the cycles of the ewes. In Experiment 1, we used 138 Corriedale ewes to evaluate two factors: synchronization treatment (sponges versus a single injection of prostaglandin) and type of pasture (native versus improved with Lotus corniculatus). Ewes were mated at the end of the grazing period and prolificacy was evaluated at lambing. Grazing Lotus corniculatus for 12 days tended to increase the number of twin lambs born (P=0.09). The percentage of ewes showing oestrus during a 9-day period was similar among synchronization treatments. Animals in Experiments 2 (n=282) and 3 (n=288) were allocated to a control group or a group fed a supplement of corn grain and soybean meal for 7 days. Ewes received 2 prostaglandin injections and the supplement was fed from Days 11 to 17 after the second prostaglandin. Ovulation rate was measured in 65 (Experiment 2) and 61 (Experiment 3) ewes that were confirmed to have consumed the supplement and showed oestrus in a 4-day period. The supplement increased ovulation rate by 14% in both experiments (P<0.05). We conclude that Corriedale ewes can respond with increases in prolificacy to a 12-day period grazing Lotus corniculatus and in ovulation rate to 7 days feeding with a supplement rich in energy and protein. Moreover, in these studies, prostaglandin was as effective as sponges for synchronising oestrus, an important factor in future decisions about hormonal management of fertility.

Starting Ovsynch protocol on day 6 of first postpartum estrous cycle increased fertility in dairy cows by affecting ovarian response during heat stress.

PubMed

Dirandeh, E

2014-10-01

The objective was to compare fertility in cows using an Ovsynch protocol starting on day 6 of first postpartum estrous cycle with an Ovsynch protocol initiated at random stages of the estrous cycle during heat stress (temperature-humidity index (THI)=77-83). Cows (n=459) at the beginning of the lactation period were randomly assigned to time-of-ovulation synchronization treatments: (1) control, Ovsynch (first GnRH treatment, PGF2α treatment 7 days later, second GnRH treatment 56 h later, and TAI 16 h later), initiated at random stages of the estrous cycle (40 ± 2 days postpartum, n=224) and (2) Ovsynch initiated on day 6 of first postpartum estrous cycle (estrus=day 0) based on detection of the first estrus after day 30 postpartum (O6, 35 ± 2 postpartum, n=235). Statistical analyses were conducted using SAS. The percentage of cows responding to the initial GnRH injection using the Ovsynch protocol was greater with the O6 treatment compared to the control treatment (60.4% compared with 52.6%). The percentage of cows having a corpus luteum (CL) on the day of the PGF2α injection was not different among treatments (control=87.0% and O6=90.2%, respectively). Also more cows in the O6 treatment group responded to the second GnRH injection of the Ovsynch protocol compared with control treatments (82.5% compared with 75.8%). Treatment affected the percentage of cows diagnosed pregnant at 32 ± 0.7 days and 60 ± 3 days after the resynchronized timing of AI but pregnancy losses (5.3% compared with 6.8%) did not differ between treatment groups. It is concluded that initiating the Ovsynch protocol 6 days after estrus during the first 40 days postpartum resulted in a greater pregnancy rate at the synchronized estrus and increased fertility compared with control cows during heat stress. Copyright © 2014 Elsevier B.V. All rights reserved.

Effect of different hormonal combinations on follicular wave emergence and superovulatory response in sheep.

PubMed

Souza-Fabjan, Joanna Maria Gonçalves; da Rosa, Rômulo Mendonça; Balaro, Mário Felipe Alvarez; Pinto, Pedro Henrique Nicolau; Dos Santos, Gustavo Bervian; Arashiro, Eduardo Kenji Nunes; da Fonseca, Jeferson Ferreira; Ungerfeld, Rodolfo; Brandão, Felipe Zandonadi

2017-11-01

The aim of the present study was to compare hormonal treatments to induce and synchronize follicular wave emergence to improve the results of superovulatory (SOV) treatments in ewes. In Experiment 1 (n = 66), ewes were treated with a progesterone intravaginal implant plus a PGF 2α analogue (group G P4 ), or with the same treatment plus estradiol benzoate (G P4+EB ), a GnRH agonist (G P4+GnRH ), or both, estradiol benzoate and a GnRH agonist (G P4+EB+GnRH ) in a 2 × 2 factorial arrangement. Follicular wave emergence was determined by ultrasound. Follicular wave did not emerge during the studied period in 10 females (one from G P4 , six from G P4+EB and three from G P4+EB+GnRH ). Follicular emergence was less synchronized (P = 0.007) when estradiol was administered (G P4+EB : 103.6 ± 22.0 h), without any interaction with GnRH treatment (G P4+EB+GnRH : 80.1 ± 21.4 h, G P4+GnRH : 52.5 ± 8.7 h, G P4 : 56.6 ± 10.4 h). Estradiol administration delayed the moment of follicular emergence (P = 0.007) and the follicular wave emergence moment in which follicular dominance was achieved (P = 0.009), without interactions between estradiol and GnRH in the moment of follicular wave emergence or dominance. In Experiment 2 (n = 22), two SOV protocols were compared: the best treatment of Experiment 1 (G P4 ) was used to synchronize follicular wave emergence, initiating the SOV treatment 2.5 days later; in the control treatment, SOV treatment started 80 h after a short-term protocol to synchronize ovulation (G control ). The number of corpora lutea (CL) and the evaluation of the collected embryos were performed six days after estrus. Blood samples were collected daily for plasma progesterone determination. Although the number of CL was similar in G control (7.1 ± 1.0) and G P4 (6.9 ± 5.1), the number of structures and viable embryos recovered were greater in G control (P < 0.05). The occurrence of luteal premature regression was significantly greater in G P4 (60%) than in G control (8.3%). The use of GnRH agonist alone did not improve synchronization of follicular wave emergence. When EB was used (alone or associated) follicular wave emergence was less synchronized. The SOV protocol proposed had a similar ovarian response; however, it resulted in less transferable embryos. Copyright © 2017 Elsevier Inc. All rights reserved.

Corpus luteum function following single and double ovulation during estrous cycle in Sanjabi ewes.

PubMed

Shabankareh, H Karami; Habibizad, J; Torki, M

2009-09-01

This study compared the effect of double and single ovulation on serum progesterone concentrations and luteal characteristics in Sanjabi ewes at different days of the estrous cycle. The estrous cycles of 197 Sanjabi ewes were synchronized by a 12-day treatment with intravaginal sponges (Chronogest). Estrus was detected in 144 ewes 27-39 h after sponge removal. Daily blood samples were taken every morning and analyzed for serum progesterone (P4). Ewes were then transported to a local abattoir, where nine ewes were slaughtered on each experimental day (days 1-16 after estrus) for ovary collection. The ovarian follicles were measured and categorized by size (very small <2mm; small 2-3.5mm; medium 3.5-5mm; large >5mm). On each slaughter day, the number of corpora lutea per ewe was classified as single and double ovulation. The results show that the effect of dominant follicles was less during the mid-luteal phase. Ovulation rate of right, left and both ovaries were (54.9%), (23.6%) and (21.5%), respectively. The incidence of double ovulations was 40.2%. In the case of ewes exhibiting double ovulation, 46.6% occurred unilateral (ewes exhibited both ovulations on the right ovary); whereas 53.4% occurred bilateral (ewes exhibited ovulations on the right and left ovaries). Unilateral double ovulation was not observed in the left ovary. The right ovary appeared to play a significantly greater role in ewes showing single and double ovulations than the left ovary (P<0.05). Serum progesterone concentration showed minimum and maximum levels of 0.29+/-0.15 and 5.51+/-0.75 ng/ml on days 16 and 11 post-estrous, respectively (P<0.001). The mean volume of individual corpus lutea in ewes with single ovulations was significantly higher than in ewes with double ovulations (P<0.01). However, the total volume of corpus lutea in ewes with single ovulation was significantly lower than in ewes with double ovulations in some days of estrous cycle (P<0.01). The serum progesterone concentration was significantly higher in double than single ovulating animals on days 1-16 of the estrous cycle (P<0.001). These results indicated a relatively high incidence of double ovulation in ewes associated with increasing total luteal volume and high circulating concentrations of progesterone.

Effect of reproductive methods and GnRH administration on long-term protocol in Santa Ines ewes.

PubMed

Biehl, Marcos V; Ferraz Junior, Marcos V C; Ferreira, Evandro M; Polizel, Daniel M; Miszura, Alexandre A; Barroso, José P R; Oliveira, Gabriela B; Bertoloni, Analisa V; Pires, Alexandre V

2017-08-01

This study aimed to determine whether reproductive performance of ewes submitted to laparoscopic timed artificial insemination (TAI) would be similar to ante meridiem (AM)/post meridiem (PM) rule and assisted natural mating (NM), and whether GnRH may enhance the pregnancy rate in TAI. In experiment I, 191 non-lactating ewes were synchronized, then TAI was performed either 48 h after progesterone (P4) removal (TAI-48 h) or 12 h after estrus detection (AM/PM); moreover, some ewes were submitted to NM (NM) as control treatment. In experiment II, 247 non-lactating ewes were allocated in five treatments, a control (no-GnRH on protocol) and four treatments arranged in a factorial design 2 × 2. The factors were time and dose of GnRH: ewes that received either 10 μg (TAI-10 μg-36 h) or 25 μg of GnRH (TAI-25 μg-36 h) 36 h after P4 removal and ewes that received either 10 μg (TAI-10 μg-48 h) or 25 μg of GnRH (TAI-25 μg-48 h) at time of insemination, 48 h after P4 removal. In experiment I, pregnancy rate in TAI-48 h was lower (P = 0.03) than AM/PM and NM. Moreover, the probability of pregnancy in TAI-48 h was higher (P = 0.06) in ewes detected in estrus early. In experiment II, the use of GnRH in TAI protocols increased (P < 0.01) pregnancy rate at synchronization, and TAI-25 μ-48 h and TAI-10 μg-36 h treatments increased (P = 0.02) pregnancy rate compered to TAI-10 μg-48 h. We conclude that TAI decreased pregnancy rate compered to NM and AM/PM, which may be improved by GnRH use in TAI to synchronize ovulation.

Influence of short-term energy supplementation on estrus, ovarian activity, and blood biochemistry in Ossimi ewes synchronized with fluorogestone acetate in the subtropics.

PubMed

Senosy, W; Mahmoud, G B; Abdel-Raheem, Sh M

2017-01-15

The objective of this study was to evaluate if short-term high-energy diet treatments have any overstimulatory effects on ovarian function and metabolic status in Ossimi ewes synchronized with progesterone sponge. Thirteen ewes were divided into high-energy (HEG; n = 7) and normal-energy or control (NEG; n = 6) groups. Progesterone sponges were placed intravaginally for 14 days during the winter breeding season (December-February). Four days before the removal of the sponges, a high-energy diet (130% of maintenance) was fed to HEG, whereas NEG was offered maintenance diet throughout the experiment. Ovarian performance and progesterone, estradiol, and blood metabolites were assessed daily starting from the day of removal of the sponges. Estrus period was longer in HEG (P < 0.05) when compared with NEG. Ovulation took place considerably longer with larger ovulatory follicles in HEG (P < 0.05). A marked increase in the level of total protein, albumin, glucose, and blood urea during the first 2 days following the removal of progesterone sponge was noticed in HEG when compared with NEG ewes. Eighty-five percentage (85.7%; 6/7) and 66.6% (4/6) had ovulation for the HEG and NEG, respectively. Dietary energy had a nonsignificant effect on the number of the recruited follicles, whereas a significant effect was observed for the diameter of the ovulatory follicle and ovulation rate (HEG, 2.3 ± 0.1 vs. NEG, 1.2 ± 0.3). It is concluded that short-term energy supplementation improves estrus expression and ovarian activity in fluorgestone acetate (FGA)-synchronized Ossimi ewes. Copyright © 2016 Elsevier Inc. All rights reserved.

Clomiphene citrate 'stair-step' protocol vs. traditional protocol in patients with polycystic ovary syndrome: a randomized controlled trial.

PubMed

Deveci, Canan Dura; Demir, Berfu; Sengul, Ozlem; Dilbaz, Berna; Goktolga, Umit

2015-01-01

To evaluate the efficacy of the stair-step protocol using clomiphene citrate (CC) and to assess the uterine and systemic side effects in patients with polycystic ovary syndrome (PCOS). A total of 60 PCOS patients who failed to respond to 50 mg/day for 5 days of CC treatment within the cycle were randomly allocated to the control (traditional protocol) and study (stair-step protocol) groups. In the stair-step protocol,patients were treated with CC 50 mg/day for 5 days and then in nonresponsive patients, the dosage was increased to 100 mg/day for 5 days in the same cycle. Patients who failed the 50 mg/day CC treatment in the previous cycle were stimulated with 100 mg/day CC and were accepted as the control group. Ovulation and pregnancy rates, duration of treatment and uterine and systemic side effects were evaluated. Ovulation and pregnancy rates were similar between the stair-step and the control group (43.3 vs. 33.3 %, respectively) (16.7 vs. 10 %, respectively). The duration of treatment was significantly shorter in stair-step compared to traditional protocol (20.5 ± 2.0 vs. 48.6 ± 2.4 days, respectively). There were no significant differences in the systemic side effects between the groups. Uterine side effects were evaluated with endometrial thickness and uterine artery Doppler ultrasound; no significant differences were observed in stair-step compared to traditional protocol. The stair-step protocol was determined to have a significantly shorter treatment period without any detrimental effect on the ovulation and pregnancy rates.

Evaluation of hormone-free protocols based on the "male effect" for artificial insemination in lactating goats during seasonal anestrus.

PubMed

Pellicer-Rubio, Maria-Teresa; Boissard, Karine; Forgerit, Yvonnick; Pougnard, Jean Louis; Bonné, Jean Luc; Leboeuf, Bernard

2016-03-15

Goat estrous and ovulatory responses to the "male effect" were characterized to determine the time range over which fertile ovulations occur after buck exposure. The results were used to explore the efficacy of different hormone-free artificial insemination (AI) protocols aimed at diminishing the number of inseminations needed to optimize fertility. Adult bucks and does were exposed to artificially long days during winter and then exposed to a natural photoperiod before buck exposure (Day 0). Most goats (>70%) ovulated twice, developing a short cycle followed by a normal cycle over 13 days after buck exposure. Among them, 21% were in estrus at the short cycle and 94% at the normal cycle. This second ovulation occurred within 48 hours of Day 6 and was the target for AI protocols. In protocol A (n = 79), goats were inseminated 12 hours after estrus detection from Day 5 to Day 9. Up to six AI times over 4 days were needed to inseminate goats in estrus. Forty-nine percent of the inseminated goats kidded. In protocol B (n = 145), estrus detection started on Day 5. The earlier (group 1) and later (group 2) buck-marked goats received one single insemination at fixed times on Days 6.5 or 7 and 8, respectively; unmarked goats (group 3) were inseminated along with group 2. In protocol C (n = 153), goats were inseminated twice on Days 6.5 or 7 and 8 without needing to detect estrus. Goats induced to ovulate by hormonal treatment were used as the control (n = 319). Fertility was lower in protocol B than in protocol C and controls (47% vs. 58% and 65% kidding; P ≤ 0.05), whereas this was higher in buck-marked goats than in unmarked ones (64% vs. 33%; P ≤ 0.05). In protocol B, fertility can increase (>60%) when only goats coming into estrus are inseminated. The best kidding rate (∼70%) was achieved when does were inseminated within 24 hours of the LH surge. Protocols involving insemination on Day 7 instead of Day 6.5 led to more goats being inseminated during this favorable time. Copyright © 2016 Elsevier Inc. All rights reserved.

Short term protein supplementation during a long interval prostaglandin-based protocol for timed AI in sheep.

PubMed

Errandonea, N; Fierro, S; Viñoles, C; Gil, J; Banchero, G; Olivera-Muzante, J

2018-03-21

The aim of this study was to evaluate the reproductive impact of a short-term protein supplementation on a long interval prostaglandin-based protocol (two PG injections 15 d apart; PG15) for timed artificial insemination in sheep. During the breeding season, 437 multiparous Merino ewes grazing native pastures (forage allowance of 6 kg of dry matter/100 kg of live weight; crude protein: 10.8%, metabolic energy: 2.1 Mcal/kg of dry matter) were selected. Ewes were allocated, according to body condition score (3.2 ± 0.2) and body weight (40.6 ± 4.9 kg, mean ± SD), to a 2 × 2 factorial design: type of estrus -spontaneous estrus (SE) or induced with PG15 (PG15)-, and supplementation (yes or no) before insemination (+FF; soybean meal at Days -10 to -3; crude protein: 51.9%, metabolic energy: 2.8 Mcal/kg of dry matter; average consumption 0.9% live weight/ewe/day of dry matter). All ewes were cervically artificial inseminated (Day -2 to -3 in SE ewes at estrus detection; Day 0 = timed artificial insemination in PG15 ewes). Ovulation rate on Day 7, non-return to service on Day 23, conception, fertility, prolificacy and fecundity on Day 60 were evaluated. Ovulation rate (1.17 ± 0.40 vs. 1.06 ± 0.25), non-return to service at Day 23 (81.7 vs. 64.2%), conception (78.8 vs. 61.5%), fertility (75.2 vs. 61.5%) and fecundity (0.77 vs. 0.62) were higher in ewes from SE than PG15 group (P < 0.05). However, no differences were observed in prolificacy (1.02 ± 0.16 vs. 1.01 ± 0,12) between groups (P > 0.05). Protein supplementation increased ovulation rate (1.30 ± 0.45 vs. 1.17 ± 0.40), prolificacy (1.18 ± 0.39 vs. 1.02 ± 0.16) and fecundity (0.94 vs. 0.77%; P < 0.05), but not non-return to service on Day 23 (83.8 vs. 81.7%), conception (82.9 vs. 78.8%) or fertility (79.1 vs. 75.2%; P > 0.05) in SE group. The supplement feed to PG15 ewes increased ovulation rate (1.35 ± 0.45 vs. 1.06 ± 0.25), prolificacy (1.25 ± 0.43 vs. 1.01 ± 0.12) and fecundity (0.79 vs. 0.62%; P < 0.05) to levels comparable to SE + FF ewes (P > 0.05). The magnitude of the increase in ovulation rate in PG15 was greater than in the SE group (27 vs. 11%; P < 0.05). However, non-return to service on Day 23 (65.1 vs. 64.2%), conception (63.3 vs 61.5%), and fertility rate (63.3 vs. 61.5%; P < 0.05) remained similar in PG15 supplemented or not supplemented ewes. In conclusion, a short-term protein supplementation before cervical time artificial insemination improved the reproductive performance of ewes synchronized with the PG15 protocol to levels comparable to the SE group. Copyright © 2018 Elsevier Inc. All rights reserved.

Effect of a new device for sustained progesterone release on the progesterone concentration, ovarian follicular diameter, time of ovulation and pregnancy rate of ewes.

PubMed

Dias, Lilian Mara Kirsch; de Barros, Marina Berrettini Paes; Viau, Priscila; Sales, José Nélio de Sousa; Valentim, Renato; dos Santos, Fernanda Ferreira; da Cunha, Manoel Claudio; Marino, Carolina Tobias; de Oliveira, Claudio Alvarenga

2015-04-01

This study evaluated the effectiveness of a new progesterone intravaginal device (DPR) in ewes through four experiments: Experiment 1 compared the circulating progesterone concentration of ovariectomized ewes that received either a new or a re-used DPR. Experiment 2 compared the progesterone concentration between DPR-estrous-synchronized ewes and naturally estrous-cycling ewes. Experiment 3 evaluated the effect of new and re-used DPRs on ovarian follicular dynamics and time of ovulation of estrous cycling ewes. Experiment 4 compared the pregnancy rate after the use of a DPR and Controlled Internal Drug Releasing Device (CIDR). The mean concentration of progesterone released by the DPR device during its first use (New Group: 5.1 ± 0.5 ng/ml) was greater than that during the second use (Re-used Group: 2.4 ± 0.3 ng/ml). There was no difference between the animals that received DPR devices for first and second use in terms of ovulatory follicle diameter, follicular wave emergence day for ovulatory follicle and period of ovulatory wave of ovarian follicular development. However, there was a significant difference between groups regarding the time between DPR device removal and first ovulation (New Group: 71.7 ± 2.5h and Re-Used Group: 63.9 ± 2.7h). Pregnancy rates were similar between ewes with DPR and CIDR devices. It was concluded that DPR is effective in increasing and maintaining progesterone concentrations, controlling follicular dynamics, promoting synchronized times of ovulation from healthy follicles, promoting development of a competent corpus luteum and when used results in pregnancy rates similar to that with use of the CIDR. Copyright © 2015 Elsevier B.V. All rights reserved.

Clomiphene citrate before and after withdrawal bleeding for induction of ovulation in women with polycystic ovary syndrome: Randomized cross-over trial.

PubMed

Elbohoty, Ahmed E H; Amer, Mohamed; Abdelmoaz, Mohamed

2016-08-01

To compare the ovarian response to early versus late clomiphene citrate (CC) in women with polycystic ovary syndrome (PCOS). This cross-over randomized controlled clinical trial included 90 infertile amenorrheic women with PCOS. After inducing withdrawal bleeding, patients were randomly divided into two equal groups to receive ovulation induction with CC 100 mg/day for 5 days. Group I started treatment the next day after finishing medroxyprogesterone acetate course for a menstrual cycle, and after a washout period of another menstrual cycle, the treatment was shifted to start on day 2 of withdrawal bleeding. Group II received a reversed protocol: late then early treatment. Women were followed up on transvaginal ultrasonography to monitor follicular growth, endometrial thickness and evidence of ovulation. Human chorionic gonadotropin 10 000 IU was given i.m. to trigger ovulation when at least one mature follicle measured ≥18 mm at day 14. In all cases, early induction protocol resulted in significantly higher proportion of ovulating patients, thicker endometrium and higher number of follicles 14-17 mm in diameter, ≥ 18 mm in diameter and total number of follicles (P < 0.001 for all comparisons). In women with PCOS, early initiation of CC before withdrawal bleeding or during the last days of the luteal phase can achieve a better ovulatory response. © 2016 Japan Society of Obstetrics and Gynecology.

Control of the estrous cycle in guinea-pig (Cavia porcellus).

PubMed

Grégoire, A; Allard, A; Huamán, E; León, S; Silva, R M; Buff, S; Berard, M; Joly, T

2012-09-01

The aim of this work was to look for a simple method to obtain synchronized ovulation in guinea pigs under farming conditions while respecting animal welfare. The luteolytic activity of three different prostaglandins F2alpha (PGF2α) analogs (D-cloprostenol, D,L-cloprostenol and luprostiol) and a daily treatment with oral progestagen (altrenogest) was tested successively at different stages of the estrous cycle on the same group of females during a period of 8 mo. The estrous cycle length was not modified by the administration of PGF2α analogs, whatever the stage of the estrous cycle when the treatment was initiated. Our results led us to reject the use of PGF2α analog to induce practical synchronization of the estrus in this species. In females (n = 29), given 15 days with altrenogest (0.1 mL po once a day), ovulation occurred 4.43 ± 0.13 days after the end of the treatment. Altrenogest treatment was followed by mating. No negative impacts of the treatment on the pregnancy rates, delivery rates and litter sizes were observed. This standard method of guinea-pig estrus synchronization is less stressful for the animals compared to techniques using progesterone tubing. Copyright © 2012 Elsevier Inc. All rights reserved.

A synthetic kisspeptin analog that triggers ovulation and advances puberty

PubMed Central

Decourt, C.; Robert, V.; Anger, K.; Galibert, M.; Madinier, J.-B.; Liu, X.; Dardente, H.; Lomet, D.; Delmas, A. F.; Caraty, A.; Herbison, A. E.; Anderson, G. M; Aucagne, V.; Beltramo, M.

2016-01-01

The neuropeptide kisspeptin and its receptor, KiSS1R, govern the reproductive timeline of mammals by triggering puberty onset and promoting ovulation by stimulating gonadotrophin-releasing hormone (GnRH) secretion. To overcome the drawback of kisspeptin short half-life we designed kisspeptin analogs combining original modifications, triazole peptidomimetic and albumin binding motif, to reduce proteolytic degradation and to slow down renal clearance, respectively. These analogs showed improved in vitro potency and dramatically enhanced pharmacodynamics. When injected intramuscularly into ewes (15 nmol/ewe) primed with a progestogen, the best analog (compound 6, C6) induced synchronized ovulations in both breeding and non-breeding seasons. Ovulations were fertile as demonstrated by the delivery of lambs at term. C6 was also fully active in both female and male mice but was completely inactive in KiSS1R KO mice. Electrophysiological recordings of GnRH neurons from brain slices of GnRH-GFP mice indicated that C6 exerted a direct excitatory action on GnRH neurons. Finally, in prepubertal female mice daily injections (0.3 nmol/mouse) for five days significantly advanced puberty. C6 ability to trigger ovulation and advance puberty demonstrates that kisspeptin analogs may find application in the management of livestock reproduction and opens new possibilities for the treatment of reproductive disorders in humans. PMID:27245315

A Three-day PGF2α Plus eCG-based Fixed-time AI Protocol Improves Fertility Compared with Spontaneous Estrus in Dairy Cows with Silent Ovulation

PubMed Central

GARCIA-ISPIERTO, Irina; LÓPEZ-GATIUS, Fernando

2013-01-01

Abstract This study was designed to test the treatment with prostaglandin F2α (PGF2α) plus equine chorionic gonadotrophin (eCG) and GnRH 48 h later (PEG protocol) followed by fixed-time AI (FTAI) in dairy cows with silent ovulation (cows with a mature corpus luteum and no signs of estrus detected in the preceding 21 days). In Experiment I, ovulation following the PEG protocol monitored in 24 cows with silent ovulation was recorded in 83% of the cows 36 h after GnRH treatment. In Experiment II, control cows were artificially inseminated during spontaneous estrus (4615 AI), while cows in the PEG group (1266 AI) were subjected to FTAI 24 h after GnRH treatment. Binary logistic regression revealed a significant effect of the interactions of treatment by season, by parity or by repeat breeding syndrome (>3 AI) on the conception rate. The conception rate was negatively affected by the warm season and age in controls but not in treated cows, whereas repeat breeder cows in the control and PEG groups were less (by a factor of 0.7) or more (by a factor of 1.5) likely to become pregnant, respectively, than the remaining animals. Moreover, the likelihood of twin pregnancy was lower in multiparous PEG (by a factor of 0.4) cows than in the remaining cows. This protocol, besides overcoming the negative effects of heat stress and age on the conception rate, increased fertility in repeat breeder cows compared with spontaneous estrus. Moreover, this treatment regimen reduced the twin pregnancy rate in multiparous cows. PMID:23698789

Estrous cycle regulatory mechanisms of the uterus are altered in cows that do not demonstrate behavioral estrus during an ovulation induction protocol

USDA-ARS?s Scientific Manuscript database

Estrus is the start of an estrous cycle in cows, and triggers several precisely timed events including receptivity to the bull, ovulation, conception, formation of the corpus luteum, and recognition of pregnancy. In the absence of a pregnancy signal, the corpus luteum (CL) must regress in response ...

Evaluation of portable near infrared spectrophotometer to stage maturity in channel catfish

USDA-ARS?s Scientific Manuscript database

Gonadal maturity of channel catfish varies within the same cohort of fish. Female channel catfish with superior maturity need to be identified and staged for higher success to induce spawn wit ovulating hormones to produce channel x blue hybrid catfish fry in hatcheries. Maturation is not synchron...

Study of consensus-based time synchronization in wireless sensor networks.

PubMed

He, Jianping; Li, Hao; Chen, Jiming; Cheng, Peng

2014-03-01

Recently, various consensus-based protocols have been developed for time synchronization in wireless sensor networks. However, due to the uncertainties lying in both the hardware fabrication and network communication processes, it is not clear how most of the protocols will perform in real implementations. In order to reduce such gap, this paper investigates whether and how the typical consensus-based time synchronization protocols can tolerate the uncertainties in practical sensor networks through extensive testbed experiments. For two typical protocols, i.e., Average Time Synchronization (ATS) and Maximum Time Synchronization (MTS), we first analyze how the time synchronization accuracy will be affected by various uncertainties in the system. Then, we implement both protocols on our sensor network testbed consisted of Micaz nodes, and investigate the time synchronization performance and robustness under various network settings. Noticing that the synchronized clocks under MTS may be slightly faster than the desirable clock, by adopting both maximum consensus and minimum consensus, we propose a modified protocol, MMTS, which is able to drive the synchronized clocks closer to the desirable clock while maintaining the convergence rate and synchronization accuracy of MTS. © 2013 ISA. Published by ISA. All rights reserved.

Oestradiol-17β plasma concentrations after intramuscular injection of oestradiol benzoate or oestradiol cypionate in llamas (Lama glama)

PubMed Central

2010-01-01

Background Llamas (Lama glama) are induced ovulators and the process of ovulation depends on dominant follicular size. In addition, a close relationship between behavioural estrus and ovulation is not registered in llamas. Therefore, the exogenous control of follicular development with hormones aims to predict the optimal time to mate. Oestradiol-17β (E2) and its esters are currently used in domestic species, including camelids, in synchronization treatments. But, in llamas, there is no reports regarding the appropriate dosages to be used and most protocols have been designed by extrapolation from those recommended for other ruminants. The aim of the present study was to characterize plasma E2 concentrations in intact female llamas following a single intramuscular (i.m.) injection of two oestradiol esters: oestradiol benzoate (EB) and oestradiol cypionate (ECP). Methods Twelve non pregnant and non lactating sexually mature llamas were i.m. injected on day 0 with 2.5 mg of EB (EB group, n = 6) or ECP (ECP group, n = 6). Blood samples were collected immediately before injection, at 1, 6, 12, 24 h after treatment and then daily until day 14 post injection. Changes in hormone concentrations with time were analyzed in each group by analysis of variance (ANOVA) using a repeated measures (within-SS) design. Plasma E2 concentrations and area under the concentration-time curve (AUC) values were compared between groups by ANOVA. In all cases a Least-Significant Difference test (LSD) was used to determine differences between means. Hormonal and AUC data are expressed as mean ± S.E.M. Results Peak plasma E2 concentrations were achieved earlier and were higher in EB group than in ECP group. Thereafter, E2 returned to physiological concentrations earlier in EB group (day 5) than in ECP group (day 9). Although plasma E2 profiles differed over time among groups there were no differences between them on AUC values. Conclusions The i.m. injection of a single dose of both oestradiol esters resulted in plasma E2 concentrations exceeding physiological values for a variable period. Moreover, the plasma E2 profiles observed depended on the derivative of oestradiol administered. This basic information becomes relevant at defining treatment protocols including oestrogens in llamas. PMID:20149242

Early postpartum administration of equine chorionic gonadotropin to dairy cows calved during the hot season: Effects on fertility after first artificial insemination.

PubMed

Patron-Collantes, R; Lopez-Helguera, I; Pesantez-Pacheco, J L; Sebastian, F; Fernández, M; Fargas, O; Astiz, S

2017-04-01

Heat stress reduces fertility of high-producing dairy cows, and early administration of equine chorionic gonadotropin (eCG) may improve it. Here, 401 heat-stressed, high-producing dairy cows on a single commercial farm were given eCG (500 UI, n = 214) or saline (n = 187) on days 11-17 after calving, and the effects on fertility after the first artificial insemination (AI) were assessed. On post-partum day 96.34 ± 9.88, all cows were inseminated after a "double short Cosynch" synchronization protocol. Ovarian activity and uterine status were checked by ultrasound on the day of eCG administration and every 7 days thereafter for a total of 3 weeks; checks were also performed during synchronization, and 7 days after AI. On post-partum day 30, cytobrush uterine cytology was performed to check for subclinical endometritis. Pregnancy status was checked on days 30 and 60 after AI. The eCG and control groups did not differ significantly in terms of average lactations per cow (2.33 ± 1.34), days in milk at first AI (96.33 ± 9.88), average milk yield at AI (41.38 ± 7.74 L), or the particular inseminator or bull used for AI. The eCG and control groups showed increasing ovarian activity with time, with approximately 75% of cows in both groups showing a corpus luteum at the beginning of the synchronization protocol. On post-partum day 30, 17.4% of eCG cows and 22.9% of control cows showed subclinical endometritis. Cows treated with eCG showed a tendency toward lower hyperecogenic intraluminal content (16.8 vs. 21.4%, P = 0.15), but ovarian activity during the synchronization protocol was similar between eCG and control groups, with 91% of animals in both groups showing luteolysis after prostaglandin application and 88% showing ovulation after the last administration of gonadotropin-releasing hormone. Fertility was similar between the two groups at both time points after AI (30 days, 34.9 vs. 31.8%; 60 days, 30.6 vs. 28.5%; P > 0.2). These results suggest that early postpartum eCG administration does not improve fertility of heat-stressed dairy cows as long as 60 days after AI. Other strategies may be more effective at mitigating the ability of post-partum heat stress to reduce fertility of high-producing dairy cows. Copyright © 2017 Elsevier Inc. All rights reserved.

The use of altrenogest to avoid hyperestrogenism after eCG-hCG ovulation induction in southern tigrina (Leopardus guttulus).

PubMed

Micheletti, Tatiane; Brown, Janine L; Walker, Susan L; Cubas, Zalmir S; Furtado, Priscila V; Putman, Sarah B; de Moraes, Wanderlei; de Oliveira, Marcos J; de Oliveira, Claudio A; Moreira, Nei

2015-09-01

The goal of this study was to optimize an ovulation induction protocol for use with artificial insemination in the southern tigrina (Leopardus guttulus). The specific aims were to report the efficacy of using altrenogest, an oral progestin (Regumate, MSD Animal Health, Merck Animal Health), to suppress ovarian activity and prevent follicular hyperstimulation and hyperestrogenism after the administration of exogenous eCG and hCG. To monitor ovarian responses, fecal estrogen and progestogen metabolites were quantified by enzyme immunoassay in females before and after intramuscular administration of 200-IU eCG and 150-IU hCG in two trials, 4 months apart. During the first trial, there was no use of altrenogest, only the eCG-hCG ovulation induction protocol. In the second trial, the ovulation induction protocol was preceded by the administration of oral altrenogest for 14 days (minimum of 0.192 mg per kg per day). Altrenogest administration resulted in a suppression of follicular activity in three out of six females before eCG-hCG administration on the basis of lower mean estrogen concentrations (P < 0.05). It also resulted in four out of six females presenting lower fecal estrogen metabolite concentrations (P < 0.05) after ovulation induction, and two out of six individuals showed a reduction (P < 0.05) in postovulatory fecal progestogen metabolite concentrations, all when compared to the same female's cycles without the progestin. Fecal estrogen metabolite concentrations were closer to baseline in 50% of these individuals after altrenogest and eCG-hCG treatments when compared to basal concentrations before gonadotropins without the use of altrenogest. This study reported that use of altrenogest in southern tigrina can suppress ovarian activity and avoid hyperestrogenism after administration of eCG and hCG treatment. However, not all females responded uniformly, so more studies are needed to increase the efficacy of ovulation induction for use with artificial insemination in this species. Copyright © 2015 Elsevier Inc. All rights reserved.

The effect of follicle age on conception rate in beef heifers

USDA-ARS?s Scientific Manuscript database

The objective of this study was to determine the effect of age of the ovulatory follicle on fertility in beef heifers. Ovulation was synchronized with the 5 d CO-Synch + CIDR program in heifers in Montana (n = 162, Hereford and Angus Crossbred; MT) and Ohio (n = 170, Angus Crossbred; OH). All heifer...

Effect of P.G. 600 on the timing of ovulation in gilts treated with altrenogest.

PubMed

Horsley, B R; Estienne, M J; Harper, A F; Purcell, S H; Baitis, H K; Beal, W E; Knight, J W

2005-07-01

We previously reported that ovulation rate, but not pregnancy rate or litter size at d 30 after mating, was enhanced by treatment with P.G. 600 (400 IU of PMSG and 200 IU of hCG, Intervet America, Inc., Millsboro, DE) in gilts fed the orally active progestin, altrenogest (Matrix, Intervet America, Inc.) to synchronize estrus. We hypothesized that in addition to increasing ovulation rate, P.G. 600 may have altered the timing of ovulation. Therefore, mating gilts 12 and 24 h after first detection of estrus, as is common in the swine industry, may not have been the optimal breeding regimen, and as a consequence, pregnancy rate and litter size were not altered. The objective of the present study was to determine the effect of P.G. 600 on the timing of ovulation in gilts treated with altrenogest. Randomly cycling, crossbred gilts (5.5 mo old, 117 kg BW, and 14.7 mm of backfat) were fed a diet containing altrenogest (15 mg/d) for 18 d. Twenty-four hours after altrenogest withdrawal, gilts received i.m. injections of P.G. 600 (n = 25) or saline (n = 25). Gilts were checked for estrus at 8-h intervals. After first detection of estrus, transrectal ultrasonography was performed at 8-h intervals to determine the time of ovulation. Gilts were killed 9 to 11 d after the onset of estrus to determine ovulation rate. All gilts displayed estrus by 7 d after treatment with P.G. 600 or saline. Compared with saline, P.G. 600 increased (P = 0.07) ovulation rate (14.8 vs. 17.5, respectively; SE = 1.1). The intervals from injection to estrus (110.9 vs. 98.4; SE = 2.7 h; P < 0.01) and injection to ovulation (141.9 vs. 128.6; SE = 3.2 h; P < 0.01) were greater in gilts treated with saline than in gilts treated with P.G. 600. Duration of estrus (54.4 vs. 53.7; SE = 2.5 h), the estrus-to-ovulation interval (30.2 vs. 31.7; SE = 2.2 h), and the time of ovulation as a percentage of estrus duration (55.8 vs. 57.5; SE = 3.0%) did not differ for the P.G. 600 and saline-injected gilts, respectively. In summary, P.G. 600 advanced the onset of estrus and ovulation following termination of altrenogest treatment and increased ovulation rate; however, treatment of gilts with P.G. 600 had no effect on the timing of ovulation relative to the onset of estrus.

A synthetic auxin (NAA) suppresses secondary wall cellulose synthesis and enhances elongation in cultured cotton fiber.

PubMed

Singh, Bir; Cheek, Hannah D; Haigler, Candace H

2009-07-01

Use of a synthetic auxin (naphthalene-1-acetic acid, NAA) to start (Gossypium hirsutum) ovule/fiber cultures hindered fiber secondary wall cellulose synthesis compared with natural auxin (indole-3-acetic acid, IAA). In contrast, NAA promoted fiber elongation and ovule weight gain, which resulted in larger ovule/fiber units. To reach these conclusions, fiber and ovule growth parameters were measured and cell wall characteristics were examined microscopically. The differences in fiber from NAA and IAA culture were underpinned by changes in the expression patterns of marker genes for three fiber developmental stages (elongation, the transition stage, and secondary wall deposition), and these gene expression patterns were also analyzed quantitatively in plant-grown fiber. The results demonstrate that secondary wall cellulose synthesis: (1) is under strong transcriptional control that is influenced by auxin; and (2) must be specifically characterized in the cotton ovule/fiber culture system given the many protocol variables employed in different laboratories.

Analysis of Proximity-1 Space Link Interleaved Time Synchronization (PITS) Protocol

NASA Technical Reports Server (NTRS)

Woo, Simon S.

2011-01-01

To synchronize clocks between spacecraft in proximity, the Proximity-1 Space Link Interleaved Time Synchronization (PITS) Protocol has been proposed. PITS is based on the NTP Interleaved On-Wire Protocol and is capable of being adapted and integrated into CCSDS Proximity-1 Space Link Protocol with minimal modifications. In this work, we will discuss the correctness and liveness of PITS. Further, we analyze and evaluate the performance of time synchronization latency with various channel error rates in different PITS operational modes.

β-Nerve growth factor is a major component of alpaca seminal plasma and induces ovulation in female alpacas.

PubMed

Kershaw-Young, C M; Druart, X; Vaughan, J; Maxwell, W M C

2012-01-01

Ovulation in camelids is induced by an unidentified protein in the seminal plasma of the male termed 'ovulation-inducing factor'. This protein has been reported to be a 14-kDa protein under reducing conditions, which, when purified from seminal plasma, induces ovulation in llamas. The identification of this protein and investigation of its potential to induce ovulation in camelids may aid the development of protocols for the induction of ovulation. In the present study, alpaca seminal plasma proteins were separated using one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis and the most abundant protein of 14 kDa was identified as β-nerve growth factor (β-NGF) by liquid chromatography mass spectrometry. Female alpacas (n = 5 per group) were given intramuscular injections of: (1) 1 mL of 0.9% saline; (2) 4 µg buserelin, a gonadotrophin-releasing hormone agonist; (3) 2 mL alpaca seminal plasma; or (4) 1mg human β-NGF. Ovulation was detected by transrectal ultrasonography 8 days after treatment and confirmed by plasma progesterone concentrations. Ovulation occurred in 0%, 80%, 80% and 80% of animals treated with saline, buserelin, seminal plasma and β-NGF, respectively. Treatment type did not affect the diameter of the corpus luteum, but plasma progesterone concentrations were lower in saline-treated animals than in the other treatment groups owing to the lack of a corpus luteum. The present study is the first to identify the ovulation-inducing factor protein in alpacas. β-NGF successfully induces ovulation in alpacas and this finding may lead to new methods for the induction of ovulation in camelids.

Effect of altering the intervals between consecutive superovulatory doses of porcine follicle-stimulating hormone on ovarian responses and embryo yields in anestrous ewes.

PubMed

Bartlewski, P M; Murawski, M; Schwarz, T; Oliveira, M E F

2017-05-01

The effect of varying intervals between successive gonadotropin injections on the superovulatory outcomes in anestrous Rideau Arcott ewes superstimulated for ovarian follicular development with multiple doses of porcine FSH (pFSH) was evaluated in a single study. Twenty-five animals received six (1×2.5ml and 5×1.25ml) injections of Folltropin ® -V given at 0800 and 1600h or at 0800 and 2000h in Group 1 (n=9) or Group 2 (n=16), respectively. An i.m. injection of 500 IU of equine chorionic gonadotropin (eCG; Folligon ® ) was given concurrently with the first pFSH dose. Time of estrus was synchronized among ewes with intravaginal sponges containing 60mg of medroxyprogesterone acetate (Veramix ® ) that were left in place for 14days; sponges were removed at the time of the 5th pFSH injection. Six days after insertion of MAP sponges, all ewes received an i.m. injection of estradiol-17β dissolved in 1ml of sesame oil (350μg/ewe) to synchronize follicular wave emergence. Following the last pFSH dose, all animals were given a single i.m. injection of 50μg of gonadotropin-releasing hormone (GnRH; Cystorelin ® ) to induce ovulations before placing in a pen with four fertile rams for 36h. The ovarian responses were assessed and embryos recovered surgically 7days after GnRH injections. The mean number of corpora lutea was greater (P<0.05) in Group 1 compared with Group 2 ewes (21.0±2.9 compared with 10.4±1.6, respectively; mean±SEM) but there was no difference (P>0.05) in the number of transferable embryos (5.4±2.4 compared with 5.4±1.3/ewe, respectively), and Group 1 animals had significantly more degenerated embryos than Group 2 ewes (2.6±1.2 compared with 0.6±0.3/ewe, respectively). A superovulatory protocol wherein pFSH injections were given at 0800 and 1600h was more effective in terms of inducing multiple ovulations than the protocol with 12-h intervals between consecutive pFSH doses, but it was not associated with an increased production of transferable quality embryos by anestrous ewes. Copyright © 2017 Elsevier B.V. All rights reserved.

The effect of follicle age on pregnancy rate in beef cows

USDA-ARS?s Scientific Manuscript database

The objective of this study was to test the effect of age of the ovulatory follicle on fertility in beef cows. Ovulation was synchronized with the 5 d CO-Synch + CIDR program in multiparous (n = 171) and primiparous (n = 130) postpartum beef cows in two groups (G1 and G2) before application of treat...

The effect of Follicle Age on Pregnancy Rate in Beef Cows

USDA-ARS?s Scientific Manuscript database

The objective of this study was to test the effect of age of the ovulatory follicle on fertility in beef cows. Ovulation was synchronized with the 5 d CO-Synch + CIDR program in multiparous (n = 171) and primiparous (n = 130) postpartum beef cows in two groups (G1 and G2) before application of treat...

Effects of extending the length of pro-oestrus in an oestradiol- and progesterone-based oestrus synchronisation program on ovarian function, uterine environment and pregnancy establishment in beef heifers.

PubMed

de la Mata, J J; Núñez-Olivera, R; Cuadro, F; Bosolasco, D; de Brun, V; Meikle, A; Bó, G A; Menchaca, A

2018-05-21

The aim of the present study was to investigate the effects of a strategy for extending pro-oestrus (the interval between luteolysis and ovulation) in an oestrus synchronisation protocol (named J-Synch) in beef heifers on follicular growth, sexual steroid concentrations, the oestrogen receptor ERα and progesterone receptors (PR) in the uterus, insulin-like growth factor (IGF) 1 and pregnancy rates. In Experiment 1, heifers treated with the new J-Synch protocol had a longer pro-oestrus period than those treated with the conventional protocol (mean (±s.e.m.) 93.7±12.9 vs 65.0±13.7h respectively; P<0.05). The rate of dominant follicle growth from the time of progesterone device removal to ovulation was greater in heifers in the J-Synch than conventional group (P<0.05). Luteal area and serum progesterone concentrations were greater in the J-Synch Group (P<0.05) for the 12 days after ovulation. Progesterone receptor (PGR) staining on Day 6 after ovulation in the uterine stroma was lower in the J-Synch than conventional group (P<0.05), and the expression of PR gene (PGR) and IGF1 gene tended to be lower in J-Synch-treated heifers (P<0.1). In Experiment 2 (n=2349), the pregnancy rate 30-35 days after fixed-time AI (FTAI) was greater for heifers in the J-Synch than conventional group (56.1% vs 50.7% respectively). In conclusion, our strategy for extending pro-oestrus (i.e. the J-Synch protocol) significantly improves pregnancy establishment in beef heifers. This improvement was related to an increased rate of growth of the dominant ovulatory follicle, greater progesterone concentrations during the ensuing luteal phase and different uterine patterns of PGR and IGF1, which may have favoured embryo development and pregnancy establishment.

Time Synchronization and Distribution Mechanisms for Space Networks

NASA Technical Reports Server (NTRS)

Woo, Simon S.; Gao, Jay L.; Clare, Loren P.; Mills, David L.

2011-01-01

This work discusses research on the problems of synchronizing and distributing time information between spacecraft based on the Network Time Protocol (NTP), where NTP is a standard time synchronization protocol widely used in the terrestrial network. The Proximity-1 Space Link Interleaved Time Synchronization (PITS) Protocol was designed and developed for synchronizing spacecraft that are in proximity where proximity is less than 100,000 km distant. A particular application is synchronization between a Mars orbiter and rover. Lunar scenarios as well as outer-planet deep space mother-ship-probe missions may also apply. Spacecraft with more accurate time information functions as a time-server, and the other spacecraft functions as a time-client. PITS can be easily integrated and adaptable to the CCSDS Proximity-1 Space Link Protocol with minor modifications. In particular, PITS can take advantage of the timestamping strategy that underlying link layer functionality provides for accurate time offset calculation. The PITS algorithm achieves time synchronization with eight consecutive space network time packet exchanges between two spacecraft. PITS can detect and avoid possible errors from receiving duplicate and out-of-order packets by comparing with the current state variables and timestamps. Further, PITS is able to detect error events and autonomously recover from unexpected events that can possibly occur during the time synchronization and distribution process. This capability achieves an additional level of protocol protection on top of CRC or Error Correction Codes. PITS is a lightweight and efficient protocol, eliminating the needs for explicit frame sequence number and long buffer storage. The PITS protocol is capable of providing time synchronization and distribution services for a more general domain where multiple entities need to achieve time synchronization using a single point-to-point link.

True and sham acupuncture produced similar frequency of ovulation and improved LH to FSH ratios in women with polycystic ovary syndrome.

PubMed

Pastore, Lisa M; Williams, Christopher D; Jenkins, Jeffrey; Patrie, James T

2011-10-01

Acupuncture may represent a nonpharmaceutical treatment for women with polycystic ovary syndrome (PCOS), based on four studies. The objective of the study was to determine whether true, as compared with sham, acupuncture normalizes pituitary gonadotropin hormones and increases ovulatory frequency in women with PCOS. This was a randomized, double-blind, sham-controlled clinical trial (5 month protocol). The study was conducted in central Virginia. Eighty-four reproductive-aged women completed the intervention. Eligibility required a PCOS diagnosis and no hormonal intervention 60 d before enrollment. Intervention included 12 sessions of true or sham acupuncture (Park sham device) for 8 wk. Serum LH and FSH at baseline, after intervention, and 3 months later were measured. Ovulation was measured with weekly urine or blood samples. Both arms demonstrated a similar mean ovulation rate over the 5 months (0.37/month among n = 40 true acupuncture and 0.40/month among n = 44 sham participants, P = 0.6), similar LH to FSH ratio improvement (-0.5 and -0.8 true and sham, respectively, P < 0.04 after intervention vs. baseline) and a similar decline in LH over the 5-month protocol (P < 0.05). Neither arm experienced a change in FSH. There were seven pregnancies (no difference by intervention, P = 0.7). Lower fasting insulin and free testosterone were highly correlated with a higher ovulation rate within the true acupuncture group only (P = 0.03), controlling for prestudy menstrual frequency and body mass index. We were unable to discern a difference between the true and sham acupuncture protocols for these women with PCOS, and both groups had a similar improvement in their LH/FSH ratio.

Ovulation rate, antral follicle count, and circulating anti-Müllerian hormone in Trio allele carriers, a novel high fecundity bovine genotype.

PubMed

García-Guerra, Alvaro; Motta, Jéssica C L; Melo, Leonardo F; Kirkpatrick, Brian W; Wiltbank, Milo C

2017-10-01

High fecundity genotypes in sheep are a valuable model to study the physiological mechanisms underlying follicle selection and the control of ovulation rate. Similar genotypes in cattle had not been described until the recent identification of a major bovine allele, termed Trio, which had a large effect on ovulation rate. The present study was designed to evaluate ovulation rate, antral follicle count (AFC), circulating ant-müllerian hormone (AMH), and the association among these measures in unstimulated and superstimulated Trio carrier cattle. We hypothesized that AFC and AMH would be variable among individual cows but would be similar between Trio carriers and non-carrier control cows and that there would be no association between these measures of follicle numbers and ovulation rate. In experiment 1, ovulation rate was determined during 4 consecutive estrous cycles in Trio carriers (n = 34) and non-carrier controls (n = 27). Ovulation rate, on average, was greater (P < 0.01) in Trio carriers (3.5 ± 0.2) compared to non-carrier controls (1.1 ± 0.1) with ∼70% of carrier cycles (n = 136) having 3-4 ovulations while only ∼5% had single ovulations. In contrast, non-carrier cycles (n = 108) were mostly single ovulation (89%) with none having more than two ovulations. In experiment 2, AFC, determined at wave emergence, was not different (P = 0.54) between Trio carriers (24.5 ± 1.3; n = 45) and non-carrier controls (23.1 ± 0.9; n = 37), and no correlation was found between AFC and mean ovulation rate in either genotype (r = -0.009 and r = -0.07; P > 0.70, respectively). In Experiment 3, circulating AMH was also not different between genotypes (P = 0.65) while correlations were found between AFC and AMH in Trio carriers (r = 0.43; P = 0.05; n = 27) and non-carrier controls (r = 0.78; P < 0.01; n = 19). In experiment 4, AFC and AMH were determined in Trio-carriers (n = 9) in relation to a synchronized follicular wave which was unstimulated or stimulated with exogenous FSH. Stimulation with FSH increased ovulation rate, compared to unstimulated Trio carriers, however no association was found between AFC or AMH and ovulation rate regardless of whether superstimulation with exogenous FSH was used. In conclusion, the novel high fecundity bovine genotype Trio, results in consistent multiple ovulations despite having similar AFC and AMH. Therefore, our results suggest that differences in antral follicle numbers during the final stages of follicle development are not a key component of the mechanism underlying multiple ovulations in Trio carriers. Copyright © 2017. Published by Elsevier Inc.

Fixed-time induction of ovulation in camels superovulated by different eCG modalities during the transition period in Egypt : Superovulation in camels during the transition period.

PubMed

Khalifa, Marwa Ahmed; Rateb, Sherif Abdel-Razzak; El-Bahrawy, Khalid Ahmed

2016-04-01

The current investigation aimed to establish a fixed-time induction of ovulation/ insemination protocol in camels superovulated by different equine chorionic gonadotropin (eCG) regimens during the transition period in Egypt (mid-October to mid-November). Seventeen pluriparous camels, Camelus dromedarius, were used. All females retained controlled intra-vaginal drug releasers (CIDRs) for 13 consecutive days, and at CIDR withdrawal, the camels were randomly divided into three groups. The control group (n = 5) received 1 ml saline intra-muscularly (i.m.), whereas remaining camels were superovulated by 2500 IU eCG either in a single shot (SS, n = 6) or in serial decreasing doses over 3 days (DD, n = 6). Ovarian dynamics were monitored by transrectal ultrasonography at 2-day intervals, and ovulation was induced by 5000 IU hCG i.m. The changes in reproductive hormones throughout the period of the study were determined. The results showed that mean values of total no. of follicles and size of dominant follicles remained low (P < 0.05) in all groups until day of CIDR removal. Thereafter, total follicle no. increased (P < 0.05) in both superovulated groups compared to the control, where the dominant follicles attained the highest (P < 0.05) diameter 12 days after the eCG treatment. Double-ovulation rate was higher (P < 0.05) in SS (50%) and DD (66.6%) groups compared to that of control (0.0%). However, 33.3% of the SS group developed large anovulatory follicles (ø > 25 mm), which did not respond to induction to ovulation. These results elucidate that eCG administration in serial decreasing doses generates a reliable superovulatory response in camels, and ovulation can be blindly induced 12 days after the gonadotropin treatment. This fixed-time hormonal protocol represents a sufficient alternative to conventional day-to-day ultrasonography and would have profound implication for enhanced fertility in dromedary camels by facilitating infield application of embryo transfer technique.

Space Network Time Distribution and Synchronization Protocol Development for Mars Proximity Link

NASA Technical Reports Server (NTRS)

Woo, Simon S.; Gao, Jay L.; Mills, David

2010-01-01

Time distribution and synchronization in deep space network are challenging due to long propagation delays, spacecraft movements, and relativistic effects. Further, the Network Time Protocol (NTP) designed for terrestrial networks may not work properly in space. In this work, we consider the time distribution protocol based on time message exchanges similar to Network Time Protocol (NTP). We present the Proximity-1 Space Link Interleaved Time Synchronization (PITS) algorithm that can work with the CCSDS Proximity-1 Space Data Link Protocol. The PITS algorithm provides faster time synchronization via two-way time transfer over proximity links, improves scalability as the number of spacecraft increase, lowers storage space requirement for collecting time samples, and is robust against packet loss and duplication which underlying protocol mechanisms provide.

Fertility after two doses of PGF2α concurrently or at 6-hour interval on the day of CIDR removal in 5-day CO-Synch progesterone-based synchronization protocols in beef heifers.

PubMed

White, Stephanie S; Kasimanickam, Ramanathan K; Kasimanickam, Vanmathy R

2016-08-01

Timed artificial insemination protocols in beef cattle are designed to synchronize ovulation in a greater proportion of females while simultaneously achieving acceptable pregnancy rates and a concise calving season. Protocols achieving such goals reduce time and labor associated with estrus detection and make advanced reproductive technologies implementable for beef producers. The objective of the study was to determine the effect of three different PGF2α (PGF) dosage schemes on artificial insemination (AI) pregnancy rates in beef heifers. We hypothesized that two doses of PGF administered concurrently at the time of controlled internal drug release (CIDR) removal would attain similar pregnancy rates compared with two doses given 6-hours apart-one at CIDR removal and the next 6 hours later in the 5-day CO-Synch progesterone-based synchronization protocol. Angus heifers (n = 875) at six locations in Washington, Idaho, and Oregon states were included in this study. Heifers within locations were assigned a body condition score (BCS). All heifers received a CIDR (1.38 g of progesterone) and 100 μg IM of GnRH on Day 0. The CIDRs were removed on Day 5, heifers were randomly allocated to one of three protocol groups: 1PGF (n = 291), received 25 mg IM of dinoprost (PGF); 2CO-PGF (n = 291), received 50 mg IM of dinoprost at CIDR removal, 2PGF (n = 293), received 25 mg IM of dinoprost at CIDR removal, and an additional 25 mg IM of dinoprost 6 hours later. Each heifer was given GnRH (100 μg, IM) and artificially inseminated at 56 hours after CIDR removal. Heifers were examined for pregnancy status between 50 and 70 days after AI to determine time of conception. A mixed-model procedure (PROC GLIMMIX of SAS) was used to evaluate the effect of treatments (1PGF, 2CO-PGF, and 2PGF) on AI pregnancy rates. Models included were treatments, BCS categories (≤5 and >5), and treatment by BCS category interaction. Location (state), handling facilities, handlers, inseminators, and AI sires were included as a random effect in the model. The 2PGF group had greater AI pregnancy rate of 63.6% (185/291), compared with the 2CO-PGF group at 51.9% (151/291) and 1PGF group at 54.9% (161/293; P < 0.001). An AI pregnancy rate of 50% (104/208) was observed for heifers with BCS less than or equal to 5 versus 58.9% (393/667) for heifers with BCS greater than 5 (P < 0.05). Location did not influence the AI pregnancy rate (P > 0.1). In conclusion, beef heifers received two 25-mg doses of PGF at 6-hour interval on Day 5 at CIDR insert removal in a 5-day CO-Synch + CIDR synchronization protocols achieved greater pregnancy compared with heifers received 50 mg of PGF concurrently at CIDR removal. Copyright © 2016 Elsevier Inc. All rights reserved.

Byzantine-fault tolerant self-stabilizing protocol for distributed clock synchronization systems

NASA Technical Reports Server (NTRS)

Malekpour, Mahyar R. (Inventor)

2010-01-01

A rapid Byzantine self-stabilizing clock synchronization protocol that self-stabilizes from any state, tolerates bursts of transient failures, and deterministically converges within a linear convergence time with respect to the self-stabilization period. Upon self-stabilization, all good clocks proceed synchronously. The Byzantine self-stabilizing clock synchronization protocol does not rely on any assumptions about the initial state of the clocks. Furthermore, there is neither a central clock nor an externally generated pulse system. The protocol converges deterministically, is scalable, and self-stabilizes in a short amount of time. The convergence time is linear with respect to the self-stabilization period.

Fertility after implementation of long- and short-term progesterone-based ovulation synchronization protocols for fixed-time artificial insemination in beef heifers.

PubMed

Kasimanickam, R; Schroeder, S; Hall, J B; Whittier, W D

2015-04-15

Two experiments were conducted to evaluate the effect of long-term (LT; a 14-day controlled internal drug release insert [CIDR]-PGF2α [PGF]-GnRH) and short-term (ST; 5-day CO-Synch + CIDR) progesterone-based protocols on pregnancy rate to fixed-time artificial insemination (FTAI) in beef heifers. In experiment 1, Angus cross beef heifers (N = 1887) at nine locations received a body condition score and a reproductive tract score (RTS). Within the herd, heifers were randomly assigned to LT-72 and ST-56 protocol groups. Heifers in the LT-72 group received a CIDR from Days 0 to 14, followed by 25 mg of PGF 16 days later (Day 30). Heifers in the ST-56 group received a CIDR and 100 μg of gonadorelin hydrochloride (GnRH) on Day 25 followed by 25 mg of PGF at CIDR removal on Day 30 and a second dose of PGF 6 hours later (Day 30). Artificial insemination was performed at 56 hours (Day 32) after CIDR removal for the ST-56 group and at 72 hours (Day 33) after CIDR removal for the LT-72 group, and all heifers were given GnRH (100 μg, intramuscular) at the time of AI. In experiment 2, Angus cross beef heifers (N = 718) at four locations received a body condition score and an RTS. Within the herd, heifers were randomly assigned to LT-72 and ST-72 protocol groups. The protocol was similar to experiment 1 except that AI was performed at 72 hours after CIDR removal for both LT-72 and ST-72 groups. In experiment 1, no difference in AI pregnancy rates between the LT-72 and ST-56 groups was observed (54.5% [489 of 897] and 55.5% [549 of 990], respectively; P = 0.92) after accounting for the RTS. The AI pregnancy rates for heifers with RTS 3 or less, 4, and 5 were 52.6%, 53.6%, and 59.9%, respectively (P < 0.05). In experiment 2, controlling for the RTS, no difference in AI pregnancy rates was observed between the LT-72 and ST-72 groups, 56.9% (198 of 347) and 57.8% (214 of 371), respectively (P = 0.87). The AI pregnancy rates for heifers with RTS 3 or less, 4, and 5 were 49.3%, 58.4%, and 62.1%, respectively (P < 0.05). In conclusion, heifers synchronized for fixed-time AI with LT and ST protocols resulted in a similar AI pregnancy rate. Approximately, 55% of the herd was pregnant to one insemination in 33 days with the LT protocol compared with just 8 days with the ST protocol. Copyright © 2015 Elsevier Inc. All rights reserved.

Distributed synchronization of networked drive-response systems: A nonlinear fixed-time protocol.

PubMed

Zhao, Wen; Liu, Gang; Ma, Xi; He, Bing; Dong, Yunfeng

2017-11-01

The distributed synchronization of networked drive-response systems is investigated in this paper. A novel nonlinear protocol is proposed to ensure that the tracking errors converge to zeros in a fixed-time. By comparison with previous synchronization methods, the present method considers more practical conditions and the synchronization time is not dependent of arbitrary initial conditions but can be offline pre-assign according to the task assignment. Finally, the feasibility and validity of the presented protocol have been illustrated by a numerical simulation. Copyright © 2017. Published by Elsevier Ltd.

Comments on the "Byzantine Self-Stabilizing Pulse Synchronization" Protocol: Counter-examples

NASA Technical Reports Server (NTRS)

Malekpour, Mahyar R.; Siminiceanu, Radu

2006-01-01

Embedded distributed systems have become an integral part of many safety-critical applications. There have been many attempts to solve the self-stabilization problem of clocks across a distributed system. An analysis of one such protocol called the Byzantine Self-Stabilizing Pulse Synchronization (BSS-Pulse-Synch) protocol from a paper entitled "Linear Time Byzantine Self-Stabilizing Clock Synchronization" by Daliot, et al., is presented in this report. This report also includes a discussion of the complexity and pitfalls of designing self-stabilizing protocols and provides counter-examples for the claims of the above protocol.

[Effect of progesterone on ovulation length and duration of the ovarian cycle induced by the male effect in the Barbarine ewe and the local Tunisian goat].

PubMed

Lassoued, N; Khaldi, G; Cognié, Y; Chemineau, P; Thimonier, J

1995-01-01

Two experiments were conducted on 30 Barbarine ewes (Exp 1) and 40 local Tunisian goats (Exp 2) in seasonal anoestrus (May). In both experiments, half of the females received 20 mg of progesterone intramuscularly just before male introduction (day 0). Blood samples were taken at 4 h intervals from the time of introduction of the ram, for the determination of the time of the preovulatory LH surge in response to the 'ram effect' (Exp 1) and once a day from days 1 to 8 to determine plasmatic progesterone concentrations (Exp 1, Exp 2). The ovulation rate was determined by coelioscopy at days 4 and 9, and oestrus behaviour was monitored twice daily in each experiment. In the ewe, progesterone delayed the time of the preovulatory LH surge (58.8 +/- 10.1 vs 20.5 +/- 10.7 h, P < 0.001), and suppressed hypofunctional corpora lutea (0/15 vs 7/14, P < 0.001). The induced ovulation rate was not significantly different between control and treated females (1.50 +/- 0.52 vs 1.26 +/- 0.46 respectively). Only 1 female in the control group and 2 in the treated group showed oestrus behaviour at the induced ovulation. Suppression of short cycles by progesterone treatment allowed synchronization of oestrus between days 17 and 20 compared to days 14 and 23 in the control group (P < 0.001). In the goat, all induced ovulations in the control group were followed by a short cycle. In the progesterone-treated group, 3 out of 20 goats developed abnormal induced corpora lutea (P < 0.001). First oestrus occurred between days 1 and 8 in control group and between days 2 and 3 in treated goats. Treatment with progesterone increased the percentage of females showing oestrus at induced ovulation (100 vs 35%, P < 0.001). The ovulation rate at first oestrus was increased in treated goats (1.85 vs 1.35, P < 0.001). In conclusion, 20 mg progesterone administered at day 0 is efficient at preventing the occurrence of short ovarian cycles. After ovulation induced by the male effect, the percentage of females in oestrus, and the induced ovulation rate are increased by progesterone treatment.

A Byzantine-Fault Tolerant Self-Stabilizing Protocol for Distributed Clock Synchronization Systems

NASA Technical Reports Server (NTRS)

Malekpour, Mahyar R.

2006-01-01

Embedded distributed systems have become an integral part of safety-critical computing applications, necessitating system designs that incorporate fault tolerant clock synchronization in order to achieve ultra-reliable assurance levels. Many efficient clock synchronization protocols do not, however, address Byzantine failures, and most protocols that do tolerate Byzantine failures do not self-stabilize. Of the Byzantine self-stabilizing clock synchronization algorithms that exist in the literature, they are based on either unjustifiably strong assumptions about initial synchrony of the nodes or on the existence of a common pulse at the nodes. The Byzantine self-stabilizing clock synchronization protocol presented here does not rely on any assumptions about the initial state of the clocks. Furthermore, there is neither a central clock nor an externally generated pulse system. The proposed protocol converges deterministically, is scalable, and self-stabilizes in a short amount of time. The convergence time is linear with respect to the self-stabilization period. Proofs of the correctness of the protocol as well as the results of formal verification efforts are reported.

The long pollen tube journey and in vitro pollen germination of Phalaenopsis orchids.

PubMed

Chen, Jhun-Chen; Fang, Su-Chiung

2016-06-01

Pollen biology in P. aphrodite. Orchids have a distinct reproductive program. Pollination triggers ovule development and differentiation within flowers, and fertilization occurs days to months after pollination. It is unclear how pollen tubes travel through the developing ovaries during ovule development and when pollen tubes arrive at the mature embryo sac to achieve fertilization. Here, we report a robust staining protocol to image and record the timing of pollen germination, progressive growth of pollen tubes in ovaries, and arrival of pollen tubes at embryo sacs in Phalaenopsis aphrodite. The pollen germinated and pollen tubes entered the ovary 3 days after pollination. Pollen tubes continued to grow and filled the entire cavity of the ovary as the ovary elongated and ovules developed. Pollen tubes were found to enter the matured embryo sacs at approximately 60-65 days after pollination in an acropetal manner. Moreover, these temporal changes in developmental events such as growth of pollen tubes and fertilization were associated with expression of molecular markers. In addition, we developed an in vitro pollen germination protocol, which is valuable to enable studies on pollen tube guidance and tip growth regulation in Phalaenopsis orchids and possibly in other orchid species.

Prospective, randomized comparison between raloxifene and clomiphene citrate for ovulation induction in polycystic ovary syndrome.

PubMed

de Paula Guedes Neto, Ernesto; Savaris, Ricardo Francalacci; von Eye Corleta, Helena; de Moraes, Gisele Silva; do Amaral Cristovam, Rafael; Lessey, Bruce A

2011-09-01

To compare the ovulation rate between raloxifene and clomiphene citrate (CC) in patients with polycystic ovary syndrome (PCOS). Double-blind, randomized, superiority clinical trial. Tertiary university hospital. Women with ovulatory dysfunction and PCOS based on the Rotterdam criteria. One of two oral treatments: 5 days of 100 mg/day of CC or R. Ovulation, based on follicle collapse on serial ultrasound and midsecretory serum progesterone concentration (≥3 ng/dL). The women with PCOS (n = 82) were randomized to receive CC (n = 40) or raloxifene (n = 42). From these, 68 patients finished the trial according to the protocol (CC: n = 37; raloxifene: n = 31). There were no statistically significant differences between the groups in ovulation rates per an intention-to-treat analysis based on ultrasound alone (CC: 21 of 40 vs. raloxifene: 17 of 42) or on progesterone levels (CC: 16 of 40 vs. raloxifene: 11 of 42). No serious adverse events were observed in either group. No statistically significant difference in ovulation was observed between raloxifene and clomiphene citrate in patients with PCOS with ovulatory dysfunction. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Software Modules for the Proximity-1 Space Link Interleaved Time Synchronization (PITS) Protocol

NASA Technical Reports Server (NTRS)

Woo, Simon S.; Veregge, John R.; Gao, Jay L.; Clare, Loren P.; Mills, David

2012-01-01

The Proximity-1 Space Link Interleaved Time Synchronization (PITS) protocol provides time distribution and synchronization services for space systems. A software prototype implementation of the PITS algorithm has been developed that also provides the test harness to evaluate the key functionalities of PITS with simulated data source and sink. PITS integrates time synchronization functionality into the link layer of the CCSDS Proximity-1 Space Link Protocol. The software prototype implements the network packet format, data structures, and transmit- and receive-timestamp function for a time server and a client. The software also simulates the transmit and receive-time stamp exchanges via UDP (User Datagram Protocol) socket between a time server and a time client, and produces relative time offsets and delay estimates.

Comparison of the effect of natural mating, LH, and GnRH on interval to ovulation and luteal function in llamas.

PubMed

Ratto, Marcelo; Huanca, Wilfredo; Singh, Jaswant; Adams, Gregg P

2006-02-01

Gonadotropins and GnRH have been used to electively induce ovulation in llamas and alpacas, but critical evaluation of the natural interval to ovulation after mating has not been performed nor has a direct comparison of the effects of natural mating versus hormone treatments on this interval and subsequent luteal development. The objectives of this study were to compare the effects of hormonal treatments and natural mating on ovulation induction, interval to ovulation, and luteal development in llamas. The ovaries of llamas were examined by transrectal ultrasonography once daily. Llamas with a large follicle were assigned randomly to be: (1) mated with an intact male (mated; n=10); (2) given 5 mg of LH im (LH; n=11); or (3) 50 microg of GnRH im (GnRH; n=10). Ultrasound examinations were performed every 4h from treatment (day 0) to ovulation and thereafter once daily for 15 consecutive days to monitor CL growth and regression (n=5 per group). Plasma progesterone concentrations were measured at days 0, 3, 6, 9, and 12 after treatment to evaluate CL function. The size of the largest preovulatory follicle at the time of treatment did not differ among groups (11+/-0.6, 10.5+/-0.8, 11.8+/-0.9 mm, for mated, LH, and GnRH groups, respectively; P=0.6). No differences were detected among groups (mated, LH, and GnRH) in ovulation rate (80%, 91%, 80%, respectively; P=0.6), or interval from treatment to ovulation (30.0+/-0.5, 29.3+/-0.6, 29.3+/-0.7h, respectively; P=0.9). Similarly, no differences were detected among groups (mated, LH, and GnRH) in maximum CL diameter (14.2+/-0.3, 13.2+/-0.5, and 13.0+/-0.7 mm, respectively; P=0.5), the day of maximum CL diameter (7.6+/-0.2, 7.6+/-0.2, and 7.4+/-0.4 mm, respectively; P=0.6), or the day on which the CL began to regress (12.3+/-0.3 [non-pregnant, n=3], 11.8+/-0.6, 12.2+/-0.4, respectively; P=0.4). The diameter of the CL and plasma progesterone concentrations changed over days (P<0.0001) but the profiles did not differ among groups. In summary, ovulation rate, interval to ovulation, and luteal development were similar among llamas that were mated naturally or treated with LH or GnRH. We conclude that both hormonal preparations are equally reliable for inducing ovulation and suitable for synchronization for artificial insemination or embryo transfer program.

Using Integer Clocks to Verify the Timing-Sync Sensor Network Protocol

NASA Technical Reports Server (NTRS)

Huang, Xiaowan; Singh, Anu; Smolka, Scott A.

2010-01-01

We use the UPPAAL model checker for Timed Automata to verify the Timing-Sync time-synchronization protocol for sensor networks (TPSN). The TPSN protocol seeks to provide network-wide synchronization of the distributed clocks in a sensor network. Clock-synchronization algorithms for sensor networks such as TPSN must be able to perform arithmetic on clock values to calculate clock drift and network propagation delays. They must be able to read the value of a local clock and assign it to another local clock. Such operations are not directly supported by the theory of Timed Automata. To overcome this formal-modeling obstacle, we augment the UPPAAL specification language with the integer clock derived type. Integer clocks, which are essentially integer variables that are periodically incremented by a global pulse generator, greatly facilitate the encoding of the operations required to synchronize clocks as in the TPSN protocol. With this integer-clock-based model of TPSN in hand, we use UPPAAL to verify that the protocol achieves network-wide time synchronization and is devoid of deadlock. We also use the UPPAAL Tracer tool to illustrate how integer clocks can be used to capture clock drift and resynchronization during protocol execution

Effect of postpartum suppression of ovulation on uterine involution in dairy cows.

PubMed

Heppelmann, M; Brömmling, A; Weinert, M; Piechotta, M; Wrenzycki, C; Bollwein, H

2013-09-15

The objective of this study was to investigate the effect of time of first postpartum ovulation after calving on uterine involution in dairy cows with and without uterine puerperal disease. Transvaginal follicular puncture (FP) of follicles >6 mm suppressed ovulation and development of a CL until Day 42 after calving. Fifty-three lactating Holstein Friesian cows (3.4 ± 1.2 years old, parity 2.5 ± 1.0 [median ± mean absolute deviation]) were divided into groups on the basis of the presence (UD+) or absence (UD-) of uterine disease and whether FP was carried out (FP+) or not (FP-). Uterine disease was defined as the occurrence of retained fetal membranes and/or metritis. This resulted in the following groups: UD-FP- (n = 15), UD-FP+ (n = 13), UD+FP- (n = 13), and UD+FP+ (n = 12). A general examination, vaginoscopy, transrectal palpation, and transrectal B-mode sonography of the reproductive organs were conducted on Days 8, 11, 18, and 25 and then every 10 days until Day 65 after calving. After hormonal synchronization of ovulation (cloprostenol between Days 55 and 60 postpartum and GnRH 2 days later), cows were inseminated in the next spontaneous estrus. On average, the cows ovulated on Day 21.0 ± 6.0 (UD-FP-), 50.0 ± 4.0 (UD-FP+), 16.0 ± 3.0 (UD+FP-), and 48.0 ± 2.0 (UD+FP+) postpartum. Calving-to-conception interval and first-service conception rates were not affected by FP (P > 0.05). Healthy cows with FP had smaller (P < 0.05) uterine horn and cervical diameters assessed sonographically than cows without FP. FP reduced the prevalence of purulent vaginal discharge and uterine size assessed transrectally in UD+ cows (P < 0.05). The results showed that suppression of an early ovulation by transvaginal FP improved uterine involution in cows with and without uterine disease. Copyright © 2013 Elsevier Inc. All rights reserved.

IEEE-1588(Trademark) Standard for a Precision Clock Synchronization Protocol for Networked Measurement and Control Systems

DTIC Science & Technology

2002-12-01

34th Annual Precise Time and Time Interval (PTTI) Meeting 243 IEEE-1588™ STANDARD FOR A PRECISION CLOCK SYNCHRONIZATION PROTOCOL FOR... synchronization . 2. Cyclic-systems. In cyclic-systems, timing is periodic and is usually defined by the characteristics of a cyclic network or bus...incommensurate, timing schedules for each device are easily implemented. In addition, synchronization accuracy depends on the accuracy of the common

Treatment strategies for the infertile polycystic ovary syndrome patient.

PubMed

Tannus, Samer; Burke, Yechiel Z; Kol, Shahar

2015-11-01

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of reproductive age. Infertility is a prevalent presenting feature of PCOS, and approximately 75% of these women suffer infertility due to anovulation. Lifestyle modification is considered the first-line treatment and is associated with improved endocrine profile. Clomiphene citrate (CC) should be considered as the first line pharmacologic therapy for ovulation induction. In women who are CC resistant, second-line treatment should be considered, as adding metformin, laparoscopic ovarian drilling or treatment with gonadotropins. In CC treatment failure, Letrozole could be an alternative or treatment with gonadotropins. IVF is considered the third-line treatment; the 'short', antagonist-based protocol is the preferred option for PCOS patients, as it is associated with lower risk of developing ovarian hyperstimulation syndrome (specifically by using a gonadotropin--releasing hormone agonist as ovulation trigger), but with comparable outcomes as the long protocol.

Circulating anti-mullerian hormone as predictor of ovarian response to clomiphene citrate in women with polycystic ovary syndrome.

PubMed

Xi, Wenyan; Yang, Yongkang; Mao, Hui; Zhao, Xiuhua; Liu, Ming; Fu, Shengyu

2016-02-11

To investigate the impact of high circulating AMH on the outcome of CC ovulation induction in women with PCOS. This prospective cohort observational study included 81 anovulatory women with PCOS who underwent 213 cycles of CC ovarian stimulation. Serum AMH concentrations were measured on cycle day 3 before the commencement of CC in the first cycle, which were compared between responders and CC-resistant anovulation (CRA). Logistic regression analysis was applied to study the value of serum AMH for the prediction of ovarian responsiveness to CC stimulation. The receiver-operating characteristic (ROC) curve was used to evaluate the prognostic value of circulating AMH. Serum AMH levels. Women who ovulated after CC therapy had a significantly lower AMH compared with the CRA (5.34 ± 1.97 vs.7.81 ± 3.49, P < 0.001). There was a significant gradient increase of serum AMH levels with the increasing dose of CC required to achieve ovulation (P < 0.05). In multivariate logistic regression analysis, AMH was an independent predictor of ovulation induction by CC in PCOS patients. ROC curve analysis showed AMH to be a useful predictor of ovulation induction by CC in PCOS patients, having 92 % specificity and 65 % sensitivity when the threshold AMH concentration was 7.77 ng/ml. Serum AMH may be clinically useful to predict which PCOS women are more likely to respond to CC treatment and thus to direct the selection of protocols of ovulation induction.

The Amelioration of Olfactory Acuity upon Sexual Maturation Might Affect Food Preferences

PubMed Central

Bignetti, Enrico; Sinesio, Fiorella; Aiello, Gaetano L.; Cannella, Carlo

2009-01-01

Upon sexual maturation, olfactory acuity in women ameliorates and starts oscillating across the cycle. During ovulation, mean olfactory threshold is 30 times lower than during bleeding. Interestingly, menstruated women undergo maleodorant trimethylaminuria. We argued that olfactory amelioration during ovulation might concur to a mating strategy, whereas olfactory impairment during bleeding might protect women against self-refusal. Testosterone and its 17β-estradiol derivative might be responsible for the synchronization of these menstrual events. Furthermore, we posed the question whether olfactory detection amelioration upon sexual maturation might provoke a change in food preferences, for instance a reduction in fish consumption. A preliminary survey in Italy provided encouraging results: 15-44 year-old women have lower fish consumption than 3-14 year-old girls. Surprisingly, men exhibited the same behaviour, so new olfactory tests as well as testosterone measurements are under way. PMID:22253964

Effect of pre- and postpartum supplementation with lipid-encapsulated conjugated linoleic acid on reproductive performance and the growth hormone-insulin-like growth factor-I axis in multiparous high-producing dairy cows.

PubMed

Csillik, Z; Faigl, V; Keresztes, M; Galamb, E; Hammon, H M; Tröscher, A; Fébel, H; Kulcsár, M; Husvéth, F; Huszenicza, Gy; Butler, W R

2017-07-01

The objective of the study was to evaluate the effect of prepartum and postpartum (PP) supplementation with 2 isomers of conjugated linoleic acid (CLA) on reproductive parameters and some related metabolic factors in dairy cows. High-producing, multiparous Holstein Friesian cows (n = 60) were allotted to 3 treatment groups: the CLA1 group (n = 20) was supplemented with 70 g of lipid-encapsulated CLA providing 7 g each of cis-9,trans-11 and trans-10,cis-12 CLA from d 21 (d 21) before expected calving until d 7 after artificial insemination (AI), that is, until 77 to 91 d PP; the CLA2 group (n = 20) was supplemented with the same amount of CLA beginning at calving until d 7 after AI; and the control group (n = 20) received an isocaloric, isonitrogenous, and isolipidic diet. Blood samples were taken weekly to measure glucose, insulin, insulin-like growth factor-I (IGF-I), and leptin. Liver biopsy was performed in 10 cows per group for growth hormone receptor 1A and IGF-I mRNA analyses. At d 49 to 63 PP, ovulation was synchronized with the Pre-Synch protocol followed by fixed-time AI. Milk progesterone was monitored from calving until d 35 post-AI. Cows returning to estrus following AI were inseminated. Supplementation with CLA before calving improved the recovery of plasma leptin levels in the early PP period (from the day of calving until wk 3 PP; treatment effect). Later PP (wk 5), plasma IGF-I, and leptin remained significantly higher in both CLA1 and CLA2 groups compared with control, although hepatocellular IGF-I mRNA was not different among groups. Plasma IGF-I levels remained higher in both CLA-treated groups on the day of AI. Growth hormone receptor 1A mRNA levels in hepatic tissue decreased in all groups, reaching a nadir in the first week PP. Days to first PP ovulation did not differ between groups; however, both supplemented groups conceived earlier compared with control (d 97 ± 19, d 97 ± 23, and d 113 ± 30 for CLA1, CLA2, and control, respectively). Plasma progesterone concentration was higher in both supplemented groups on d 2 to 5 following the synchronized ovulation than in controls. We concluded that CLA supplementation around calving alters PP metabolic signals as reflected by higher plasma leptin and IGF-I levels. Conjugated linoleic acid stimulated early luteal function and reduced the PP interval to conception. The Authors. Published by the Federation of Animal Science Societies and Elsevier Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).

Parturition prediction and timing of canine pregnancy

PubMed Central

Kim, YeunHee; Travis, Alexander J.; Meyers-Wallen, Vicki N.

2007-01-01

An accurate method of predicting the date of parturition in the bitch is clinically useful to minimize or prevent reproductive losses by timely intervention. Similarly, an accurate method of timing canine ovulation and gestation is critical for development of assisted reproductive technologies, e.g. estrous synchronization and embryo transfer. This review discusses present methods for accurately timing canine gestational age and outlines their use in clinical management of high-risk pregnancies and embryo transfer research. PMID:17904630

Ovarian follicular dynamics and plasma steroid concentrations are not significantly different in ewes given intravaginal sponges containing either 20 or 40 mg of fluorogestone acetate.

PubMed

Letelier, C A; Contreras-Solis, I; García-Fernández, R A; Ariznavarreta, C; Tresguerres, J A F; Flores, J M; Gonzalez-Bulnes, A

2009-03-01

Although various progestagens are often used to induce and synchronize estrus and ovulation in ruminants, concerns regarding residues are the impetus to develop alternative approaches, including reduced doses of progestagens. Therefore, the objective was to determine whether ovarian function was affected by halving the dose of fluorogestone acetate in intravaginal sponges for synchronizing ovulation in sheep during the physiologic breeding season. Twenty Manchega ewes, 4-6-year-old, were randomly allocated to receive an intravaginal sponge containing either 20mg (P20, n=10) or 40 mg of fluorogestone acetate (P40, n=10). Cloprostenol (125 microg) was given at sponge insertion, and all sponges were removed after 6d. Ovarian follicular dynamics (monitored by daily ultrasonography) and other aspects of ovarian function did not differ significantly between the two groups. Ovulatory follicles (OF) grew at a similar growth rate (r=0.62; P<0.001), with comparable initial and maximum diameters (4.2+/-0.4 to 6.0+/-0.3mm in P20 vs. 4.6+/-0.6 to 5.7+/-0.2 mm in P40, mean+/-S.E.M.). Plasma estradiol concentrations (determined once daily) increased linearly during the 72 h interval after sponge removal (1.3+/-0.1 to 3.3+/-0.1 pg/mL for P20, P<0.005 and 1.4+/-0.1 to 3.1+/-0.2 pg/mL for P40, P<0.005). Ten days after sponge removal, ovulation rates (1.2+/-0.2 for P20 and 1.4+/-0.3 for P40), and plasma progesterone concentrations (3.8+/-0.35 ng/mL for P20 and 3.9+/-0.38 ng/mL for P40) were similar. In conclusion, reducing the dose of fluorogestone acetate from 40 to 20mg did not affect significantly ovarian follicular dynamics or other aspects of ovarian function.

Fertility following CIDR based synchronization regimens in anoestrous Nili-Ravi buffaloes.

PubMed

Naseer, Z; Ahmad, E; Singh, J; Ahmad, N

2011-10-01

The objective of this study was to compare oestrus expression and fertility rate in used and new controlled internal drug releasing (CIDR) device treated anoestrous buffaloes. Furthermore, to determine the timing of ovulation, and fertility rate in estradiol benzoate (EB) and GnRH-administered CIDR-treated anoestrous Nili-Ravi buffaloes. In experiment 1, buffaloes received either a used CIDR (UCIDR, n = 35) or a new CIDR (NCIDR, n = 36) for 7 day and PGF2α on day 6. Oestrous expression was similar (p > 0.05) between UCIDR (88.5%) and NCIDR (96.6%) buffaloes. The pregnancy rate did not differ (p > 0.05) because of treatment (37.1% in UCIDR vs 36.6% in NCIDR). In experiment 2, buffaloes (n = 55) received CIDR device for 7 days and PGF2α, on day 6 and randomly assigned into three treatment groups: (i) CIDR-EB (n = 17) received EB on day 8, (ii) CIDR-GnRH (n = 18) received GnRH on day 9 and (iii) control (n = 20) received no further treatment. Mean interval from CIDR removal to ovulation in CIDR-EB, CIDR-GnRH and CIDR group were 61.3 ± 0.8, 64.9 ± 1.8 and 65.1 ± 16.7 h, respectively. However, the buffaloes in the CIDR-EB and CIDR-GnRH group had lesser variability in the timing of ovulation compared to control. The pregnancy rate of both CIDR-EB group (58%) and CIDR-GnRH group (61%) were tended to be higher (p < 0.1) than control (30%). In conclusion, compared to NCIDR devices, previously UCIDR devices are equally effective to induce oestrus in anoestrous buffaloes resulting optimal pregnancy rate. Administration of EB and GnRH after CIDR removal results in tighter synchrony (less variability) and improved fertility in anoestrous buffaloes. CIDR based synchronization regimens have great potential in fertility improvement in anoestrous buffaloes. © 2011 Blackwell Verlag GmbH.

How to make optimal use of maximal multipartite entanglement in clock synchronization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ren, Changliang; Hofmann, Holger F.

2014-12-04

We introduce a multi-party quantum clock synchronization protocol that makes optimal use of the maximal multipartite entanglement of GHZ-type states. The measurement statistics of the protocol are analyzed and the efficiency is evaluated.

Reproductive performance of lactating dairy cows after inducing ovulation using hCG in a five-day progesterone-based fixed-time AI protocol.

PubMed

Garcia-Ispierto, I; De Rensis, F; Casas, X; Caballero, F; Mur-Novales, R; López-Gatius, F

2018-02-01

This study compares the effects of inducing ovulation using human chorionic gonadotropin (hCG) or gonadotropin releasing hormone (GnRH) at the end of a 5-day progesterone(P4)-based protocol for fixed-time artificial insemination (FTAI) in lactating dairy cows on ovarian dynamics and fertility. A P4 intravaginal device (PRID) was fitted for five days and GnRH administered upon PRID insertion and a double dose (24 h apart) of prostaglandin F 2α upon PRID removal. Cows received either GnRH (GnRH group; n = 98), 1000 IU hCG (hCG-1 group; n = 97), or 3000 IU hCG (hCG-2 group; n = 104) 36 h after PRID removal and were inseminated 50-56 h after PRID removal. Based on Tukey-Kramer tests, cows in hCG-1 and hCG-2 showed a larger follicle diameter at AI than cows in GnRH (P < 0.05). HCG-2 treatment increased corpus luteum (CL) size on Day 7 post-AI compared with the GnRH and hCG-1 treatments (P < 0.05). Based on odds ratios, the likelihood of ovulation failure decreased with increasing follicle diameter at AI (P = 0.002). Cows in hCG-1 or hCG-2 that did not become pregnant were more likely to return to estrus than cows in GnRH (P < 0.01). A larger CL size post-AI was related to an increased conception rate at FTAI (P = 0.003). Cows given hCG-2 treatment showed a 1.9-fold cumulative pregnancy rate after two rounds of AI compared to cows receiving GnRH. Our results indicate that hCG treatment hCG treatment used to induce ovulation at the end of a short protocol for FTAI improves follicular/luteal dynamics compared to GnRH treatment. Of the two hCG treatments tested, better results were obtained with the 3000 IU dose. Copyright © 2017 Elsevier Inc. All rights reserved.

A Self-Stabilizing Distributed Clock Synchronization Protocol for Arbitrary Digraphs

NASA Technical Reports Server (NTRS)

Malekpour, Mahyar R.

2011-01-01

This report presents a self-stabilizing distributed clock synchronization protocol in the absence of faults in the system. It is focused on the distributed clock synchronization of an arbitrary, non-partitioned digraph ranging from fully connected to 1-connected networks of nodes while allowing for differences in the network elements. This protocol does not rely on assumptions about the initial state of the system, other than the presence of at least one node, and no central clock or a centrally generated signal, pulse, or message is used. Nodes are anonymous, i.e., they do not have unique identities. There is no theoretical limit on the maximum number of participating nodes. The only constraint on the behavior of the node is that the interactions with other nodes are restricted to defined links and interfaces. We present an outline of a deductive proof of the correctness of the protocol. A model of the protocol was mechanically verified using the Symbolic Model Verifier (SMV) for a variety of topologies. Results of the mechanical proof of the correctness of the protocol are provided. The model checking results have verified the correctness of the protocol as they apply to the networks with unidirectional and bidirectional links. In addition, the results confirm the claims of determinism and linear convergence. As a result, we conjecture that the protocol solves the general case of this problem. We also present several variations of the protocol and discuss that this synchronization protocol is indeed an emergent system.

Introduction: Management of the luteal phase in assisted reproductive technology.

PubMed

Griesinger, Georg; Meldrum, David

2018-05-01

The increasing utilization of a gonadotropin-releasing hormone agonist ovulation trigger and the widespread use of artificial cycles for the transfer of frozen-thawed or donated embryos has renewed interest in the luteal phase in assisted reproductive technology. The "luteal phase defect" phenomenon is now understood as a continuum: there is less impairment with milder stimulation than with more intense ovarian stimulation, and less impairment after controlled ovarian stimulation and human chorionic gonadotropin ovulation triggering than after gonadotropin-releasing hormone agonist ovulation triggering, the latter being associated with rapid luteolysis. The intensity of the support of luteal phase necessary to achieve optimal outcomes therefore depends on the degree of luteal phase defect encountered in different treatment protocols. Ultimately, the luteal phase of an artificial cycle in which ovulation is suppressed, a corpus luteum is therefore absent, and the establishment of endometrial receptivity completely relies on the orchestrated exogenous administration of sex steroids, is the litmus test situation for the study of the efficacy of different luteal phase support preparations, doses, regimens, and routes of administration. Copyright © 2018 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

A Self-Stabilizing Byzantine-Fault-Tolerant Clock Synchronization Protocol

NASA Technical Reports Server (NTRS)

Malekpour, Mahyar R.

2009-01-01

This report presents a rapid Byzantine-fault-tolerant self-stabilizing clock synchronization protocol that is independent of application-specific requirements. It is focused on clock synchronization of a system in the presence of Byzantine faults after the cause of any transient faults has dissipated. A model of this protocol is mechanically verified using the Symbolic Model Verifier (SMV) [SMV] where the entire state space is examined and proven to self-stabilize in the presence of one arbitrary faulty node. Instances of the protocol are proven to tolerate bursts of transient failures and deterministically converge with a linear convergence time with respect to the synchronization period. This protocol does not rely on assumptions about the initial state of the system other than the presence of sufficient number of good nodes. All timing measures of variables are based on the node s local clock, and no central clock or externally generated pulse is used. The Byzantine faulty behavior modeled here is a node with arbitrarily malicious behavior that is allowed to influence other nodes at every clock tick. The only constraint is that the interactions are restricted to defined interfaces.

Distributed Synchronization Control of Multiagent Systems With Unknown Nonlinearities.

PubMed

Su, Shize; Lin, Zongli; Garcia, Alfredo

2016-01-01

This paper revisits the distributed adaptive control problem for synchronization of multiagent systems where the dynamics of the agents are nonlinear, nonidentical, unknown, and subject to external disturbances. Two communication topologies, represented, respectively, by a fixed strongly-connected directed graph and by a switching connected undirected graph, are considered. Under both of these communication topologies, we use distributed neural networks to approximate the uncertain dynamics. Decentralized adaptive control protocols are then constructed to solve the cooperative tracker problem, the problem of synchronization of all follower agents to a leader agent. In particular, we show that, under the proposed decentralized control protocols, the synchronization errors are ultimately bounded, and their ultimate bounds can be reduced arbitrarily by choosing the control parameter appropriately. Simulation study verifies the effectiveness of our proposed protocols.

A Self-Stabilizing Synchronization Protocol for Arbitrary Digraphs

NASA Technical Reports Server (NTRS)

Malekpour, Mahyar R.

2011-01-01

This paper presents a self-stabilizing distributed clock synchronization protocol in the absence of faults in the system. It is focused on the distributed clock synchronization of an arbitrary, non-partitioned digraph ranging from fully connected to 1-connected networks of nodes while allowing for differences in the network elements. This protocol does not rely on assumptions about the initial state of the system, other than the presence of at least one node, and no central clock or a centrally generated signal, pulse, or message is used. Nodes are anonymous, i.e., they do not have unique identities. There is no theoretical limit on the maximum number of participating nodes. The only constraint on the behavior of the node is that the interactions with other nodes are restricted to defined links and interfaces. This protocol deterministically converges within a time bound that is a linear function of the self-stabilization period. We present an outline of a deductive proof of the correctness of the protocol. A bounded model of the protocol was mechanically verified for a variety of topologies. Results of the mechanical proof of the correctness of the protocol are provided. The model checking results have verified the correctness of the protocol as they apply to the networks with unidirectional and bidirectional links. In addition, the results confirm the claims of determinism and linear convergence. As a result, we conjecture that the protocol solves the general case of this problem. We also present several variations of the protocol and discuss that this synchronization protocol is indeed an emergent system.

Self-stabilizing byzantine-fault-tolerant clock synchronization system and method

NASA Technical Reports Server (NTRS)

Malekpour, Mahyar R. (Inventor)

2012-01-01

Systems and methods for rapid Byzantine-fault-tolerant self-stabilizing clock synchronization are provided. The systems and methods are based on a protocol comprising a state machine and a set of monitors that execute once every local oscillator tick. The protocol is independent of specific application specific requirements. The faults are assumed to be arbitrary and/or malicious. All timing measures of variables are based on the node's local clock and thus no central clock or externally generated pulse is used. Instances of the protocol are shown to tolerate bursts of transient failures and deterministically converge with a linear convergence time with respect to the synchronization period as predicted.

Effects of progestagen exposure duration on estrus synchronization and conception rates of crossbreed ewes undergoing fixed time artificial insemination.

PubMed

Blaschi, Wanessa; Lunardelli, Paula A; Marinho, Luciana S R; Max, Marilu C; Santos, Gustavo M G; Silva-Santos, Katia C; Melo-Sterza, Fabiana A; Baldassarre, Hernan; Rigo, Thales R; Seneda, Marcelo M

2014-01-01

Synchronization of estrus and ovulation are of paramount importance in modern livestock improvement programs. These methods are critical for assisted reproduction technologies, including artificial insemination and embryo transfer, that can increase productivity. In the current study, subcutaneous implants containing norgestomet were placed for long (14 days), medium (9 days), and short (5 days) periods of time in 70 crossbred ewes undergoing fixed-time artificial insemination. The resulting effects on estrus synchronization and conception rates were subsequently evaluated. Among the synchronized ewes, 85.7% (60/70) underwent estrus over a period of 72 h after progestagen treatment ceased. The shortest mean interval between withdrawal of the device and onset of estrus (34.2 ± 8.9 h) was observed in the G14 days of P4 group (p < 0.05). The conception rate of the G14 days of P4 group was statistically higher than that of the other groups (83.3% vs. 60.9% vs. 47.8%; p < 0.05). In conclusion, 14 days of norgestomet treatment produced higher conception rates and a greater number of pregnancies at the beginning of the breeding season.

Effects of progestagen exposure duration on estrus synchronization and conception rates of crossbreed ewes undergoing fixed time artificial insemination

PubMed Central

Blaschi, Wanessa; Lunardelli, Paula A.; Marinho, Luciana S.R.; Max, Marilu C.; Santos, Gustavo M.G.; Silva-Santos, Katia C.; Melo-Sterza, Fabiana A.; Baldassarre, Hernan; Rigo, Thales R.

2014-01-01

Synchronization of estrus and ovulation are of paramount importance in modern livestock improvement programs. These methods are critical for assisted reproduction technologies, including artificial insemination and embryo transfer, that can increase productivity. In the current study, subcutaneous implants containing norgestomet were placed for long (14 days), medium (9 days), and short (5 days) periods of time in 70 crossbred ewes undergoing fixed-time artificial insemination. The resulting effects on estrus synchronization and conception rates were subsequently evaluated. Among the synchronized ewes, 85.7% (60/70) underwent estrus over a period of 72 h after progestagen treatment ceased. The shortest mean interval between withdrawal of the device and onset of estrus (34.2 ± 8.9 h) was observed in the G14 days of P4 group (p < 0.05). The conception rate of the G14 days of P4 group was statistically higher than that of the other groups (83.3% vs. 60.9% vs. 47.8%; p < 0.05). In conclusion, 14 days of norgestomet treatment produced higher conception rates and a greater number of pregnancies at the beginning of the breeding season. PMID:24962414

Concentrations of nonesterified fatty acids and glucose in blood of periparturient dairy cows are indicative of pregnancy success at first insemination.

PubMed

Garverick, H A; Harris, M N; Vogel-Bluel, R; Sampson, J D; Bader, J; Lamberson, W R; Spain, J N; Lucy, M C; Youngquist, R S

2013-01-01

Greater blood concentrations of nonesterified fatty acids (NEFA) and lesser blood concentrations of glucose are indicative of the normal process of nutrient partitioning that occurs in early postpartum dairy cows. The objective was to determine the relationship between blood NEFA and glucose concentrations and subsequent conception at first insemination in postpartum dairy cows. Holstein (n=148) and Guernsey (n=8) dairy cows were blood sampled at approximately d 10, 7, and 3 prepartum, on the day of calving and 3, 7, 14, and 21 d postpartum for measurement of NEFA and glucose concentrations. Serum and plasma were harvested and used for measurement of NEFA and glucose concentrations, respectively. Cows were given a presynchronization treatment (2 injections of PGF(2α) 14 d apart) with the second PGF(2α) injection occurring 14 d before the initiation of the timed AI (TAI) protocol. Blood for determination of progesterone concentrations was collected at each presynchronization injection and at the initiation of the TAI protocol that was used for first insemination (74±7 d postpartum). Cows were considered noncycling if serum progesterone concentrations at the 2 presynchronization PGF(2α) injections (d 37 and 51±7 postpartum) and at the initiation of the TAI protocol (d 65±7 postpartum) were ≤1 ng/mL, and there was no indication of ovulation or presence of a corpus luteum by ultrasound examination at the initiation of the TAI protocol. Pregnancy was determined at 33 d and again at 61 d after first insemination by using ultrasound. Across all days, serum NEFA and plasma glucose concentrations were not different between cows that ovulated before the initiation of the TAI program (cycling) compared with those that did not ovulate (noncycling). Serum NEFA concentrations, however, were less and plasma glucose concentrations were greater during the early postpartum period for cows that subsequently became pregnant at first insemination compared with those that failed to become pregnant. Logistic regressions were used to predict the probability of pregnancy based on NEFA and glucose concentrations from individual days. The prediction with the greatest likelihood ratio was for d 3 postpartum NEFA and glucose concentrations. Nutritional status during the early postpartum period (within 1 wk after calving), as indicated by blood NEFA and glucose concentrations, may affect subsequent fertility by a mechanism that is independent from interval to first ovulation. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

UTC Time Transfer for High Frequency Trading Using IS-95 CDMA Base Station Transmissions and IEEE-1588 Precision Time Protocol

DTIC Science & Technology

2010-11-01

CDMA base stations are each synchronized by GPS receivers, they provide an indirect link to GPS system time and UTC time . The major stock...antenna synchronizes the Local Area Network (LAN) to within 10 microseconds of UTC using the IEEE-1588 Precision Time Protocol (PTP). This is an...activities. Understanding and measuring latency on the LAN is key to the success of HFTs. Without precise time synchronization below 1 millisecond

Follicle vascularity coordinates corpus luteum blood flow and progesterone production.

PubMed

de Tarso, S G S; Gastal, G D A; Bashir, S T; Gastal, M O; Apgar, G A; Gastal, E L

2017-03-01

Colour Doppler ultrasonography was used to compare the ability of preovulatory follicle (POF) blood flow and its dimensions to predict the size, blood flow and progesterone production capability of the subsequent corpus luteum (CL). Cows (n=30) were submitted to a synchronisation protocol. Follicles ≥7mm were measured and follicular wall blood flow evaluated every 12h for approximately 3.5 days until ovulation. After ovulation, cows were scanned daily for 8 days and similar parameters were evaluated for the CL. Blood samples were collected and plasma progesterone concentrations quantified. All parameters were positively correlated. Correlation values ranged from 0.26 to 0.74 on data normalised to ovulation and from 0.31 to 0.74 on data normalised to maximum values. Correlations between calculated ratios of both POF and CL in data normalised to ovulation and to maximum values ranged from moderate (0.57) to strong (0.87). Significant (P<0.0001) linear regression analyses were seen in all comparisons. In conclusion, higher correlations were observed between the dimensions of POF and/or CL and blood flow of both structures, as well as POF and/or CL blood flow with plasma progesterone concentrations of the resultant CL. These findings indicate that follicle vascularity coordinates CL blood flow and progesterone production in synchronised beef cows.

Network time synchronization servers at the US Naval Observatory

NASA Technical Reports Server (NTRS)

Schmidt, Richard E.

1995-01-01

Responding to an increased demand for reliable, accurate time on the Internet and Milnet, the U.S. Naval Observatory Time Service has established the network time servers, tick.usno.navy.mil and tock.usno.navy.mil. The system clocks of these HP9000/747i industrial work stations are synchronized to within a few tens of microseconds of USNO Master Clock 2 using VMEbus IRIG-B interfaces. Redundant time code is available from a VMEbus GPS receiver. UTC(USNO) is provided over the network via a number of protocols, including the Network Time Protocol (NTP) (DARPA Network Working Group Report RFC-1305), the Daytime Protocol (RFC-867), and the Time protocol (RFC-868). Access to USNO network time services is presently open and unrestricted. An overview of USNO time services and results of LAN and WAN time synchronization tests will be presented.

Progesterone plus PMSG Priming in seasonally anovulatory lactating Sarda ewes exposed to the ram effect.

PubMed

Todini, Luca; Malfatti, Alessandro; Barbato, Olimpia; Costarelli, Silva; Debenedetti, Alessandro

2007-04-01

The aim of this trial was to evaluate the effectiveness (fertility and lambing) of priming with a single injection of progesterone plus PMSG in anovulatory lactating Sarda ewes subjected to the ram effect (RE) in spring. Thirty ewes (P4 group) were i.m. injected with 30 mg progesterone and 500 IU PMSG 36 h before ram introduction (d 0). This treatment was compared to a 12-day treatment with fluorogestone acetate intravaginal sponges that was followed by injections of 350 IU PMSG upon sponge withdrawal (FGA group, n=30). All ewes responded to RE, showing plasma progestrone concentrations >1 ng/mL between d 6 and 12 (FGA) or 6 and 9 (P4). Eighty-nine percent of the P4 ewes conceived at first ovulation, and 11% conceived following a short estrus cycle. Lambings occurred on d 150.4 +/- 3.9, and the lambing rate was 100%. The fertility of the FGA ewes was 83% for the induced ovulation and was 7% for the second ovulation after a normal cycle. The FGA ewes lambed on d 149.8 +/- 4.4, and the lambing rate was 83%. Two abortions were recorded for the FGA ewes, which had higher prolificacy than the P4 group (2.2 +/- 0.8 vs. 1.8 +/- 0.4, respectively; P<0.05). Both fertility and the lambing rate were high in both groups, with a high degree of estrus synchronization, and there were no significant differences between the groups. We concluded that priming of lactating Sarda ewes in spring with P4+PMSG before RE is an effective and competitive method (cheaper and more practical than FGA+PMSG) of inducing fertile ovulations in these ewes.

A Unified Fault-Tolerance Protocol

NASA Technical Reports Server (NTRS)

Miner, Paul; Gedser, Alfons; Pike, Lee; Maddalon, Jeffrey

2004-01-01

Davies and Wakerly show that Byzantine fault tolerance can be achieved by a cascade of broadcasts and middle value select functions. We present an extension of the Davies and Wakerly protocol, the unified protocol, and its proof of correctness. We prove that it satisfies validity and agreement properties for communication of exact values. We then introduce bounded communication error into the model. Inexact communication is inherent for clock synchronization protocols. We prove that validity and agreement properties hold for inexact communication, and that exact communication is a special case. As a running example, we illustrate the unified protocol using the SPIDER family of fault-tolerant architectures. In particular we demonstrate that the SPIDER interactive consistency, distributed diagnosis, and clock synchronization protocols are instances of the unified protocol.

Knockdown of Progesterone Receptor (PGR) in Macaque Granulosa Cells Disrupts Ovulation and Progesterone Production.

PubMed

Bishop, Cecily V; Hennebold, Jon D; Kahl, Christoph A; Stouffer, Richard L

2016-05-01

Adenoviral vectors (vectors) expressing short-hairpin RNAs complementary to macaque nuclear progesterone (P) receptor PGR mRNA (shPGR) or a nontargeting scrambled control (shScram) were used to determine the role PGR plays in ovulation/luteinization in rhesus monkeys. Nonluteinized granulosa cells collected from monkeys (n = 4) undergoing controlled ovarian stimulation protocols were exposed to either shPGR, shScram, or no virus for 24 h; human chorionic gonadotropin (hCG) was then added to half of the wells to induce luteinization (luteinized granulosa cells [LGCs]; n = 4-6 wells/treatment/monkey). Cells/media were collected 48, 72, and 120 h postvector for evaluation of PGR mRNA and P levels. Addition of hCG increased (P < 0.05) PGR mRNA and medium P levels in controls. However, a time-dependent decline (P < 0.05) in PGR mRNA and P occurred in shPGR vector groups. Injection of shPGR, but not shScram, vector into the preovulatory follicle 20 h before hCG administration during controlled ovulation protocols prevented follicle rupture in five of six monkeys as determined by laparoscopic evaluation, with a trapped oocyte confirmed in three of four follicles of excised ovaries. Injection of shPGR also prevented the rise in serum P levels following the hCG bolus compared to shScram (P < 0.05). Nuclear PGR immunostaining was undetectable in granulosa cells from shPGR-injected follicles, compared to intense staining in shScram controls. Thus, the nuclear PGR appears to mediate P action in the dominant follicle promoting ovulation in primates. In vitro and in vivo effects of PGR knockdown in LGCs also support the hypothesis that P enhances its own synthesis in the primate corpus luteum by promoting luteinization. © 2016 by the Society for the Study of Reproduction, Inc.

Comparative Studies of Estrous Synchronization, Ovulation Induction, Luteal Function and Embryo Cryopreservation in Domestic Sheep and Application to Related Nondomestic Ungulate Species

DTIC Science & Technology

1989-12-20

adjacent pens in visual and olfactory proximity to females. All animals were fed a grain concentrate and alfalfa hay diet twice daily and allowed free...M. Bush, J.G. Howard, S.J. O’Brien, D. Meltzer, A. van Dyk, H. Ebedes and D.J. Brand. Unique seminal quality in the South African cheetah and a...hormonal characteristics of the captive male cheetah , tiger,leopard and puma. Bioi. Reprod. 38: 245-255, 1988. Wilkinson, L. SYSTAT: The System for

Temperature-Compensated Clock Skew Adjustment

PubMed Central

Castillo-Secilla, Jose María; Palomares, Jose Manuel; Olivares, Joaquín

2013-01-01

This work analyzes several drift compensation mechanisms in wireless sensor networks (WSN). Temperature is an environmental factor that greatly affects oscillators shipped in every WSN mote. This behavior creates the need of improving drift compensation mechanisms in synchronization protocols. Using the Flooding Time Synchronization Protocol (FTSP), this work demonstrates that crystal oscillators are affected by temperature variations. Thus, the influence of temperature provokes a low performance of FTSP in changing conditions of temperature. This article proposes an innovative correction factor that minimizes the impact of temperature in the clock skew. By means of this factor, two new mechanisms are proposed in this paper: the Adjusted Temperature (AT) and the Advanced Adjusted Temperature (A2T). These mechanisms have been combined with FTSP to produce AT-FTSP and A2T-FTSP Both have been tested in a network of TelosB motes running TinyOS. Results show that both AT-FTSP and A2T-FTSP improve the average synchronization errors compared to FTSP and other temperature-compensated protocols (Environment-Aware Clock Skew Estimation and Synchronization for WSN (EACS) and Temperature Compensated Time Synchronization (TCTS)). PMID:23966192

The management of anovulatory infertility in women with polycystic ovary syndrome: an analysis of the evidence to support the development of global WHO guidance.

PubMed

Balen, Adam H; Morley, Lara C; Misso, Marie; Franks, Stephen; Legro, Richard S; Wijeyaratne, Chandrika N; Stener-Victorin, Elisabet; Fauser, Bart C J M; Norman, Robert J; Teede, Helena

2016-11-01

Here we describe the consensus guideline methodology, summarise the evidence-based recommendations we provided to the World Health Organisation (WHO) for their consideration in the development of global guidance and present a narrative review on the management of anovulatory infertility in women with polycystic ovary syndrome (PCOS). The aim of this paper was to present an evidence base for the management of anovulatory PCOS. The evidence to support providing recommendations involved a collaborative process for: (i) identification of priority questions and critical outcomes, (ii) retrieval of up-to-date evidence and exiting guidelines, (iii) assessment and synthesis of the evidence and (iv) the formulation of draft recommendations to be used for reaching consensus with a wide range of global stakeholders. For each draft recommendation, the methodologist evaluated the quality of the supporting evidence that was then graded as very low, low, moderate or high for consideration during consensus. Evidence was synthesized and we made recommendations across the definition of PCOS including hyperandrogenism, menstrual cycle regulation and ovarian assessment. Metabolic features and the impact of ethnicity were covered. Management includes lifestyle changes, bariatric surgery, pharmacotherapy (including clomiphene citrate (CC), aromatase inhibitors, metformin and gonadotropins), as well as laparoscopic surgery. In-vitro fertilization (IVF) was considered as were the risks of ovulation induction and of pregnancy in PCOS. Approximately 80% of women who suffer from anovulatory infertility have PCOS. Lifestyle intervention is recommended first in women who are obese largely on the basis of general health benefits. Bariatric surgery can be considered where the body mass index (BMI) is ≥35 kg/m 2 and lifestyle therapy has failed. Carefully conducted and monitored pharmacological ovulation induction can achieve good cumulative pregnancy rates and multiple pregnancy rates can be minimized with adherence to recommended protocols. CC should be first-line pharmacotherapy for ovulation induction and letrozole can also be used as first-line therapy. Metformin alone has limited benefits in improving live birth rates. Gonadotropins and laparoscopic surgery can be used as second-line treatment. There is no clear evidence for efficacy of acupuncture or herbal mixtures in women with PCOS. For women with PCOS who fail lifestyle and ovulation induction therapy or have additional infertility factors, IVF can be used with the safer gonadotropin releasing hormone (GnRH) antagonist protocol. If a GnRH-agonist protocol is used, metformin as an adjunct may reduce the risk of ovarian hyperstimulation syndrome. Patients should be informed of the potential side effects of ovulation induction agents and of IVF on the foetus, and of the risks of multiple pregnancy. Increased risks for the mother during pregnancy and for the child, including the exacerbating impact of obesity on adverse outcomes, should also be discussed. This guidance generation and evidence-synthesis analysis has been conducted in a manner to be considered for global applicability for the safe administration of ovulation induction for anovulatory women with PCOS. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Correctness Proof of a Self-Stabilizing Distributed Clock Synchronization Protocol for Arbitrary Digraphs

NASA Technical Reports Server (NTRS)

Malekpour, Mahyar R.

2011-01-01

This report presents a deductive proof of a self-stabilizing distributed clock synchronization protocol. It is focused on the distributed clock synchronization of an arbitrary, non-partitioned digraph ranging from fully connected to 1-connected networks of nodes while allowing for differences in the network elements. This protocol does not rely on assumptions about the initial state of the system, and no central clock or a centrally generated signal, pulse, or message is used. Nodes are anonymous, i.e., they do not have unique identities. There is no theoretical limit on the maximum number of participating nodes. The only constraint on the behavior of the node is that the interactions with other nodes are restricted to defined links and interfaces. We present a deductive proof of the correctness of the protocol as it applies to the networks with unidirectional and bidirectional links. We also confirm the claims of determinism and linear convergence.

Controlador para un Reloj GPS de Referencia en el Protocolo NTP

NASA Astrophysics Data System (ADS)

Hauscarriaga, F.; Bareilles, F. A.

The synchronization between computers in a local network plays a very important role on enviroments similar to IAR. Calculations for exact time are needed before, during and after an observation. For this purpose the IAR's GNU/Linux Software Development Team implemented a driver inside NTP protocol (an internet standard for time synchronization of computers) for a GPS receiver acquired a few years ago by IAR, which did not have support in such protocol. Today our Institute has a stable and reliable time base synchronized to atomic clocks on board GPS Satellites according to computers's synchronization standard, offering precise time services to all scientific community and particularly to the University of La Plata. FULL TEXT IN SPANISH

Mechanical verification of a schematic Byzantine clock synchronization algorithm

NASA Technical Reports Server (NTRS)

Shankar, Natarajan

1991-01-01

Schneider generalizes a number of protocols for Byzantine fault tolerant clock synchronization and presents a uniform proof for their correctness. The authors present a machine checked proof of this schematic protocol that revises some of the details in Schneider's original analysis. The verification was carried out with the EHDM system developed at the SRI Computer Science Laboratory. The mechanically checked proofs include the verification that the egocentric mean function used in Lamport and Melliar-Smith's Interactive Convergence Algorithm satisfies the requirements of Schneider's protocol.

Quantum CSMA/CD Synchronous Communication Protocol with Entanglement

NASA Astrophysics Data System (ADS)

Zhou, Nanrun; Zeng, Binyang; Gong, Lihua

By utilizing the characteristics of quantum entanglement, a quantum synchronous communication protocol for Carrier Sense Multiple Access with Collision Detection (CSMA/CD) is presented. The proposed protocol divides the link into the busy time and leisure one, where the data frames are sent via classical channels and the distribution of quantum entanglement is supposed to be completed at leisure time and the quantum acknowledge frames are sent via quantum entanglement channels. The time span between two successfully delivered messages can be significantly reduced in this proposed protocol. It is shown that the performance of the CSMA/CD protocol can be improved significantly since the collision can be reduced to a certain extent. The proposed protocol has great significance in quantum communication.

Fabrication of Progesterone-Loaded Nanofibers for the Drug Delivery Applications in Bovine

NASA Astrophysics Data System (ADS)

Karuppannan, Chitra; Sivaraj, Mehnath; Kumar, J. Ganesh; Seerangan, Rangasamy; Balasubramanian, S.; Gopal, Dhinakar Raj

2017-02-01

Progesterone is a potent drug for synchronization of the estrus and ovulation cycles in bovine. At present, the estrus cycle of bovine is controlled by the insertion of progesterone-embedded silicone bands. The disadvantage of nondegradable polymer inserts is to require for disposal of these bands after their use. The study currently focuses on preparation of biodegradable progesterone-incorporated nanofiber for estrus synchronization. Three different concentrations (1.2, 1.9, and 2.5 g) of progesterone-impregnated nanofibers were fabricated using electrospinning. The spun membrane were characterized by scanning electron microscopy, X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis, and Fourier transform infrared spectroscopy. Uniform surface morphology, narrow size distribution, and interaction between progesterone and zein were confirmed by SEM. FTIR spectroscopy indicated miscibility and interaction between zein and progesterone. X-ray analysis indicated that the size of zein crystallites increased with progesterone content in nanofibers. Significant differences in thermal behavior of progesterone-impregnated nanofiber were observed by DSC. Cell viability studies of progesterone-loaded nanofiber were examined using MTT assay. In vitro release experiment is to identify the suitable progesterone concentration for estrus synchronization. This study confirms that progesterone-impregnated nanofibers are an ideal vehicle for progesterone delivery for estrus synchronization of bovines.

Relationships between fertility and postpartum changes in body condition and body weight in lactating dairy cows

PubMed Central

Carvalho, P. D.; Souza, A. H.; Amundson, M. C.; Hackbart, K. S.; Fuenzalida, M. J.; Herlihy, M. M.; Ayres, H.; Dresch, A. R.; Vieira, L. M.; Guenther, J. N.; Grummer, R. R.; Fricke, P. M.; Shaver, R. D.; Wiltbank, M. C.

2018-01-01

The relationship between energy status and fertility in dairy cattle was retrospectively analyzed by comparing fertility with body condition score (BCS) near artificial insemination (AI; experiment 1), early postpartum changes in BCS (experiment 2), and postpartum changes in body weight (BW; experiment 3). To reduce the effect of cyclicity status, all cows were synchronized with Double-Ovsynch protocol before timed AI. In experiment 1, BCS of lactating dairy cows (n = 1,103) was evaluated near AI. Most cows (93%) were cycling at initiation of the breeding Ovsynch protocol (first GnRH injection). A lower percentage pregnant to AI (P/AI) was found in cows with lower (≤2.50) versus higher (≥2.75) BCS (40.4 vs. 49.2%). In experiment 2, lactating dairy cows on 2 commercial dairies (n = 1,887) were divided by BCS change from calving until the third week postpartum. Overall, P/AI at 70-d pregnancy diagnosis differed dramatically by BCS change and was least for cows that lost BCS, intermediate for cows that maintained BCS, and greatest for cows that gained BCS [22.8% (180/789), 36.0% (243/675), and 78.3% (331/423), respectively]. Surprisingly, a difference existed between farms with BCS change dramatically affecting P/AI on one farm and no effect on the other farm. In experiment 3, lactating dairy cows (n = 71) had BW measured weekly from the first to ninth week postpartum and then had superovulation induced using a modified Double-Ovsynch protocol. Cows were divided into quartiles (Q) by percentage of BW change (Q1 = least change; Q4 = most change) from calving until the third week postpartum. No effect was detected of quartile on number of ovulations, total embryos collected, or percentage of oocytes that were fertilized; however, the percentage of fertilized oocytes that were transferable embryos was greater for cows in Q1, Q2, and Q3 than Q4 (83.8, 75.2, 82.6, and 53.2%, respectively). In addition, percentage of degenerated embryos was least for cows in Q1, Q2, and Q3 and greatest for Q4 (9.6, 14.5, 12.6, and 35.2% respectively). In conclusion, for cows synchronized with a Double-Ovsynch protocol, an effect of low BCS (≤2.50) near AI on fertility was detected, but change in BCS during the first 3 wk postpartum had a more profound effect on P/AI to first timed AI. This effect could be partially explained by the reduction in embryo quality and increase in degenerate embryos by d 7 after AI in cows that lost more BW from the first to third week postpartum. PMID:24731646

Relationships between fertility and postpartum changes in body condition and body weight in lactating dairy cows.

PubMed

Carvalho, P D; Souza, A H; Amundson, M C; Hackbart, K S; Fuenzalida, M J; Herlihy, M M; Ayres, H; Dresch, A R; Vieira, L M; Guenther, J N; Grummer, R R; Fricke, P M; Shaver, R D; Wiltbank, M C

2014-01-01

The relationship between energy status and fertility in dairy cattle was retrospectively analyzed by comparing fertility with body condition score (BCS) near artificial insemination (AI; experiment 1), early postpartum changes in BCS (experiment 2), and postpartum changes in body weight (BW; experiment 3). To reduce the effect of cyclicity status, all cows were synchronized with Double-Ovsynch protocol before timed AI. In experiment 1, BCS of lactating dairy cows (n = 1,103) was evaluated near AI. Most cows (93%) were cycling at initiation of the breeding Ovsynch protocol (first GnRH injection). A lower percentage pregnant to AI (P/AI) was found in cows with lower (≤ 2.50) versus higher (≥ 2.75) BCS (40.4 vs. 49.2%). In experiment 2, lactating dairy cows on 2 commercial dairies (n = 1,887) were divided by BCS change from calving until the third week postpartum. Overall, P/AI at 70-d pregnancy diagnosis differed dramatically by BCS change and was least for cows that lost BCS, intermediate for cows that maintained BCS, and greatest for cows that gained BCS [22.8% (180/789), 36.0% (243/675), and 78.3% (331/423), respectively]. Surprisingly, a difference existed between farms with BCS change dramatically affecting P/AI on one farm and no effect on the other farm. In experiment 3, lactating dairy cows (n = 71) had BW measured weekly from the first to ninth week postpartum and then had superovulation induced using a modified Double-Ovsynch protocol. Cows were divided into quartiles (Q) by percentage of BW change (Q1 = least change; Q4 = most change) from calving until the third week postpartum. No effect was detected of quartile on number of ovulations, total embryos collected, or percentage of oocytes that were fertilized; however, the percentage of fertilized oocytes that were transferable embryos was greater for cows in Q1, Q2, and Q3 than Q4 (83.8, 75.2, 82.6, and 53.2%, respectively). In addition, percentage of degenerated embryos was least for cows in Q1, Q2, and Q3 and greatest for Q4 (9.6, 14.5, 12.6, and 35.2% respectively). In conclusion, for cows synchronized with a Double-Ovsynch protocol, an effect of low BCS (≤ 2.50) near AI on fertility was detected, but change in BCS during the first 3 wk postpartum had a more profound effect on P/AI to first timed AI. This effect could be partially explained by the reduction in embryo quality and increase in degenerate embryos byd 7 after AI in cows that lost more BW from the first to third week postpartum. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Next Steps in Network Time Synchronization For Navy Shipboard Applications

DTIC Science & Technology

2008-12-01

40th Annual Precise Time and Time Interval (PTTI) Meeting NEXT STEPS IN NETWORK TIME SYNCHRONIZATION FOR NAVY SHIPBOARD APPLICATIONS...dynamic manner than in previous designs. This new paradigm creates significant network time synchronization challenges. The Navy has been...deploying the Network Time Protocol (NTP) in shipboard computing infrastructures to meet the current network time synchronization requirements

Characterization and manipulation of reproductive cycles in the jaguar (Panthera onca).

PubMed

Barnes, Serena A; Andrew Teare, J; Staaden, Sheryl; Metrione, Lara; Penfold, Linda M

2016-01-01

Basic reproductive information in female jaguars (Panthera onca) is lacking, thus longitudinal fecal samples from seven females were analyzed via enzyme immunoassay to measure estradiol and progestin metabolites throughout the year. Mean estrus length of 194 estrus periods measured hormonally was 6.5±0.3d, mean peak fecal estradiol concentration was 138.7±5.7ng/g; and in one female, estrus resumption occurred approximately 15d post-partum. Ovulation, as indicted by sustained elevated progestin concentrations (>20d), was successfully induced one time by treatment with exogenous hormones in one female and by physical vaginal stimulation in two females a combined total of three times. Elevated fecal progestin was observed outside exogenous stimulation on five occasions, suggesting ovulation occurred spontaneously. Mean length of physically induced and spontaneous pseudopregnancies was 24.7±4.2d and 29.6±2.6d, respectively, and mean length of pregnancy (n=2) was 98.0±0.0d. Mean peak progestin concentration for spontaneous and induced pseudopregnancies, and pregnancy was 7.4±1.4μg/g, 6.4±1.2μg/g, and 13.7±1.0μg/g, respectively. This data suggests jaguars are polyestrous and generally induced ovulators, with a moderate incidence of spontaneous ovulation. Additionally, two protocols to successfully stimulate ovarian activity in jaguars are described. Copyright © 2015 Elsevier Inc. All rights reserved.

Guaranteeing synchronous message deadlines with the timed token medium access control protocol

NASA Technical Reports Server (NTRS)

Agrawal, Gopal; Chen, Baio; Zhao, Wei; Davari, Sadegh

1992-01-01

We study the problem of guaranteeing synchronous message deadlines in token ring networks where the timed token medium access control protocol is employed. Synchronous capacity, defined as the maximum time for which a node can transmit its synchronous messages every time it receives the token, is a key parameter in the control of synchronous message transmission. To ensure the transmission of synchronous messages before their deadlines, synchronous capacities must be properly allocated to individual nodes. We address the issue of appropriate allocation of the synchronous capacities. Several synchronous capacity allocation schemes are analyzed in terms of their ability to satisfy deadline constraints of synchronous messages. We show that an inappropriate allocation of the synchronous capacities could cause message deadlines to be missed even if the synchronous traffic is extremely low. We propose a scheme called the normalized proportional allocation scheme which can guarantee the synchronous message deadlines for synchronous traffic of up to 33 percent of available utilization. To date, no other synchronous capacity allocation scheme has been reported to achieve such substantial performance. Another major contribution of this paper is an extension to the previous work on the bounded token rotation time. We prove that the time elapsed between any consecutive visits to a particular node is bounded by upsilon TTRT, where TTRT is the target token rotation time set up at system initialization time. The previous result by Johnson and Sevcik is a special case where upsilon = 2. We use this result in the analysis of various synchronous allocation schemes. It can also be applied in other similar studies.

Enhanced Precision Time Synchronization for Wireless Sensor Networks

PubMed Central

Cho, Hyuntae; Kim, Jongdeok; Baek, Yunju

2011-01-01

Time synchronization in wireless sensor networks (WSNs) is a fundamental issue for the coordination of distributed entities and events. Nondeterministic latency, which may decrease the accuracy and precision of time synchronization can occur at any point in the network layers. Specially, random back-off by channel contention leads to a large uncertainty. In order to reduce the large nondeterministic uncertainty from channel contention, we propose an enhanced precision time synchronization protocol in this paper. The proposed method reduces the traffic needed for the synchronization procedure by selectively forwarding the packet. Furthermore, the time difference between sensor nodes increases as time advances because of the use of a clock source with a cheap crystal oscillator. In addition, we provide a means to maintain accurate time by adopting hardware-assisted time stamp and drift correction. Experiments are conducted to evaluate the performance of the proposed method, for which sensor nodes are designed and implemented. According to the evaluation results, the performance of the proposed method is better than that of a traditional time synchronization protocol. PMID:22164035

Enhanced precision time synchronization for wireless sensor networks.

PubMed

Cho, Hyuntae; Kim, Jongdeok; Baek, Yunju

2011-01-01

Time synchronization in wireless sensor networks (WSNs) is a fundamental issue for the coordination of distributed entities and events. Nondeterministic latency, which may decrease the accuracy and precision of time synchronization can occur at any point in the network layers. Specially, random back-off by channel contention leads to a large uncertainty. In order to reduce the large nondeterministic uncertainty from channel contention, we propose an enhanced precision time synchronization protocol in this paper. The proposed method reduces the traffic needed for the synchronization procedure by selectively forwarding the packet. Furthermore, the time difference between sensor nodes increases as time advances because of the use of a clock source with a cheap crystal oscillator. In addition, we provide a means to maintain accurate time by adopting hardware-assisted time stamp and drift correction. Experiments are conducted to evaluate the performance of the proposed method, for which sensor nodes are designed and implemented. According to the evaluation results, the performance of the proposed method is better than that of a traditional time synchronization protocol.

SPEEDES - A multiple-synchronization environment for parallel discrete-event simulation

NASA Technical Reports Server (NTRS)

Steinman, Jeff S.

1992-01-01

Synchronous Parallel Environment for Emulation and Discrete-Event Simulation (SPEEDES) is a unified parallel simulation environment. It supports multiple-synchronization protocols without requiring users to recompile their code. When a SPEEDES simulation runs on one node, all the extra parallel overhead is removed automatically at run time. When the same executable runs in parallel, the user preselects the synchronization algorithm from a list of options. SPEEDES currently runs on UNIX networks and on the California Institute of Technology/Jet Propulsion Laboratory Mark III Hypercube. SPEEDES also supports interactive simulations. Featured in the SPEEDES environment is a new parallel synchronization approach called Breathing Time Buckets. This algorithm uses some of the conservative techniques found in Time Bucket synchronization, along with the optimism that characterizes the Time Warp approach. A mathematical model derived from first principles predicts the performance of Breathing Time Buckets. Along with the Breathing Time Buckets algorithm, this paper discusses the rules for processing events in SPEEDES, describes the implementation of various other synchronization protocols supported by SPEEDES, describes some new ones for the future, discusses interactive simulations, and then gives some performance results.

A hash based mutual RFID tag authentication protocol in telecare medicine information system.

PubMed

Srivastava, Keerti; Awasthi, Amit K; Kaul, Sonam D; Mittal, R C

2015-01-01

Radio Frequency Identification (RFID) is a technology which has multidimensional applications to reduce the complexity of today life. Everywhere, like access control, transportation, real-time inventory, asset management and automated payment systems etc., RFID has its enormous use. Recently, this technology is opening its wings in healthcare environments, where potential applications include patient monitoring, object traceability and drug administration systems etc. In this paper, we propose a secure RFID-based protocol for the medical sector. This protocol is based on hash operation with synchronized secret. The protocol is safe against active and passive attacks such as forgery, traceability, replay and de-synchronization attack.

Effects of sex pheromones and sexual maturation on locomotor activity in female sea lamprey (Petromyzon marinus)

USGS Publications Warehouse

Walaszczyk, Erin J.; Johnson, Nicholas S.; Steibel, Juan Pedro; Li, Weiming

2013-01-01

Synchronization of male and female locomotor rhythmicity can play a vital role in ensuring reproductive success. Several physiological and environmental factors alter these locomotor rhythms. As sea lamprey, Petromyzon marinus, progress through their life cycle, their locomotor activity rhythm changes multiple times. The goal of this study was to elucidate the activity patterns of adult female sea lamprey during the sexual maturation process and discern the interactions of these patterns with exposure to male pheromones. During these stages, preovulated and ovulated adult females are exposed to sex pheromone compounds, which are released by spermiated males and attract ovulated females to the nest for spawning. The locomotor behavior of adult females was monitored in a natural stream with a passive integrated tag responder system as they matured, and they were exposed to a sex pheromone treatment (spermiated male washings) or a control (prespermiated male washings). Results showed that, dependent on the hour of day, male sex pheromone compounds reduce total activity (p < 0.05) and cause increases in activity during several daytime hours in preovulated and ovulated females. These results are one of the first examples of how sex pheromones modulate a locomotor rhythm in a vertebrate, and they suggest that the interaction between maturity stage and sex pheromone exposure contributes to the differential locomotor rhythms found in adult female sea lamprey. This phenomenon may contribute to the reproductive synchrony of mature adults, thus increasing reproductive success in this species.

Prostaglandins and reproduction in female farm animals.

PubMed

Weems, C W; Weems, Y S; Randel, R D

2006-03-01

Prostaglandins impact on ovarian, uterine, placental, and pituitary function to regulate reproduction in female livestock. They play important roles in ovulation, luteal function, maternal recognition of pregnancy, implantation, maintenance of gestation, microbial-induced abortion, parturition, postpartum uterine and ovarian infections, and resumption of postpartum ovarian cyclicity. Prostaglandins have both positive and negative effects on reproduction; they are used to synchronize oestrus, terminate pseudopregnancy in mares, induce parturition, and treat retained placenta, luteinized cysts, pyometra, and chronic endometritis. Improved therapeutic uses for prostaglandins will be developed when we understand better their involvement in implantation, maintenance of luteal function, and establishment and maintenance of pregnancy.

Approximate Synchrony: An Abstraction for Distributed Almost Synchronous Systems

DTIC Science & Technology

2015-05-29

finding bugs. Verification of the TSCH Protocol. Time Synchronized Channel Hopping (TSCH) is a Medium Access Control scheme that enables low power...allotted by the schedule and remain in sleep mode otherwise. In the ab- sence of precise time-synchronization, the time-slots across nodes would not be

Distributed-observer-based cooperative control for synchronization of linear discrete-time multi-agent systems.

PubMed

Liang, Hongjing; Zhang, Huaguang; Wang, Zhanshan

2015-11-01

This paper considers output synchronization of discrete-time multi-agent systems with directed communication topologies. The directed communication graph contains a spanning tree and the exosystem as its root. Distributed observer-based consensus protocols are proposed, based on the relative outputs of neighboring agents. A multi-step algorithm is presented to construct the observer-based protocols. In light of the discrete-time algebraic Riccati equation and internal model principle, synchronization problem is completed. At last, numerical simulation is provided to verify the effectiveness of the theoretical results. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

Accelerated Growth and Initial Flowering of S2 Pinus Banksiana Selected for Precocious Flowering

Treesearch

Hyun Kang; Robert A. Cecich

1999-01-01

An accelerated growth protocol was applied in a greenhouse to hasten flowering in 13 S2 lines of jack pine (Pinus banksiana Lamb.) selected for precocious flowering. Seeds were sown on October 1. After the artificial "summer, fall, winter, and spring," seedlings were placed outdoors between June 20 and November 1. Ovulate strobili were...

A field investigation of a modified intravaginal progesterone releasing device and oestradiol benzoate based ovulation synchronisation protocol designed for fixed-time artificial insemination of Brahman heifers.

PubMed

Edwards, S A A; Boe-Hansen, G B; Satake, N; Chandra, K; McGowan, M R

2015-09-01

Pregnancy rates (PR) to fixed-time AI (FTAI) in Brahman heifers were compared after treatment with a traditional oestradiol-based protocol (OPO-8) or a modified protocol (OPO-6) where the duration of intravaginal progesterone releasing device (IPRD) was reduced from 8 to 6 days, and the interval from IPRD removal to oestradiol benzoate (ODB) was increased from 24 to 36 h. Rising 2 yo heifers on Farm A: (n = 238 and n = 215; two consecutive days AI); B (n = 271); and C (n = 393) were allocated to OPO-8 or OPO-6. An IPRD was inserted and 1mg ODB i.m. on Day 0 for OPO-8 heifers and Day 2 for OPO-6 heifers. On Day 8, the IPRD was removed and 500 μg cloprostenol i.m. At 24h, for OPO-8 heifers, and 36 h, for OPO-6 heifers, post IPRD removal all heifers received 1mg ODB i.m. FTAI was conducted at 54 and 72 h post IPRD removal for OPO-8 and OPO-6 heifers. At Farm A, OPO-6 heifers, AI on the second day, the PR was 52.4% to FTAI (P = 0.024) compared to 36.8% for OPO-8 heifers. However, no differences were found between OPO-8 and OPO-6 protocols at Farm A (first day of AI) (39.9 vs. 35.7%), or Farms B (26.2 vs. 35.4%) and C (43.2% vs. 40.3%). Presence of a corpus luteum at IPRD insertion affected PR to FTAI (43.9% vs. 28.8%; P < 0.001). This study has shown that the modified ovulation synchronisation protocol OPO-6 may be a viable alternative to the OPO-8 protocol for FTAI in B. indicus heifers. Copyright © 2015 Elsevier B.V. All rights reserved.

Performance comparison of token ring protocols for hard-real-time communication

NASA Technical Reports Server (NTRS)

Kamat, Sanjay; Zhao, Wei

1992-01-01

The ability to guarantee the deadlines of synchronous messages while maintaining a good aggregate throughput is an important consideration in the design of distributed real-time systems. In this paper, we study two token ring protocols, the priority driven protocol and the timed token protocol, for their suitability for hard real-time systems. Both these protocols use a token to control access to the transmission medium. In a priority driven protocol, messages are assigned priorities and the protocol ensures that messages are transmitted in the order of their priorities. Timed token protocols do not provide for priority arbitration but ensure that the maximum access delay for a station is bounded. For both protocols, we first derive the schedulability conditions under which the transmission deadlines of a given set of synchronous messages can be guaranteed. Subsequently, we use these schedulability conditions to quantitatively compare the average case behavior of the protocols. This comparison demonstrates that each of the protocols has its domain of superior performance and neither dominates the other for the entire range of operating conditions.

Dynamics of putative sex pheromone components during heat periods in estrus-induced cows.

PubMed

Mozūraitis, R; Kutra, J; Borg-Karlson, A-K; Būda, V

2017-09-01

Determination of the optimal insemination time in dairy cows is vital for fertilization success and is a challenging task due to silent or weak signs of estrus shown by some cows. This can be overcome by combining several estrus detection methods, leading to higher detection rates. However, an efficient, noninvasive method for detecting estrus in cows is still needed. Chemical cues released by the cow during estrus have been proposed to have pheromonal properties and signal readiness to mate to the bull. Such cues could be used in an industrial setting to detect cows in estrus. However, no conclusive published data show temporal changes in putative sex pheromone levels during estrus. The goal of this study was to determine the temporal pattern of putative sex pheromone components during estrus and to assess the reproducibility of changes in pheromone concentration with respect to ovulation time. Two injections of the hormone PGF 2α were administered over a 2-wk interval to induce and synchronize the estrous cycles of 6 Holstein cows. The precise time of ovulation was determined by means of an ultrasound technique, and estrus was determined by visual observation. Using solid-phase microextraction gas chromatography-mass spectrometry techniques, we showed that acetic and propionic acids, which have been proposed to be putative sex pheromone components in cows, were present in the headspaces of all estrous and diestrous fecal samples, whereas 1-iodoundecane was not detected by solid-phase microextraction or by solvent extraction with diethyl ether. Low levels of acids were observed until 1 d before ovulation, at which point their concentrations increased, peaking around 0.5 d before ovulation. The application of labeled synthetic standards revealed that during the peak of release, 36 ± 8 ng (average ± SD) of acetic acid and 10 ± 3 ng of propionic acid were present in 0.5-g samples of estrous-phase fecal matter compared with 19 ± 5 and 2.3 ± 1 ng of acetic and propionic acids, respectively, in the control diestrous samples. After the peak, the amounts of the compounds decreased sharply to match those of the control samples and afterward returned to the baseline readings. This decrease in the amounts of putative pheromone components was registered about 12 h before ovulation, indicating that acetic and propionic acids could be used as biomarkers for the electronic detection of ovulation. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Fenticonazole nitrate for treatment of vulvovaginitis: efficacy, safety, and tolerability of 1-gram ovules, administered as ultra-short 2-day regimen.

PubMed

Fernández-Alba, J; Valle-Gay, A; Dibildox, M; Vargas, J A; González, J; García, M; López, L H

2004-04-01

Because of its potential as a low cost first-line monotherapy for the most common vulvovaginal infections, we evaluated fenticonazole nitrate in a prospective, open-label, multicenter pilot study with 101 sexually active women (per-protocol; 16 to 61 years of age) with vulvovaginitis involving single or mixed infections with Candida albicans, Trichomonas vaginalis, and/or Gardnerella vaginalis. Fenticonazole nitrate (1 g) was administered as vaginal ovules, once daily on days 1 and 3. Eradication (direct phase-contrast microscopy of vaginal swabs and/or microbiological culture) on day 8 was 90% (C. albicans, 26/29, p < 0.001), 70% (T. vaginalis, 7/10, p = 0.161), 67% (G. vaginalis, 22/33, p < 0.009), and 45% (mixed infection, 13/29, p = 0.001). After 28 days, relapse was 0% for candidiasis and trichomoniasis, 27% (6/22) for G. vaginalis, and 23% (3/13) for mixed infection. Overall, eradication of all offending pathogens was achieved in 67% of the total per-protocol population, with a relapse rate of only 16%. Score sums for symptoms improved from 7.0 (baseline) to 1.7 (day 8), and 0.71 (day 28), (p < 0.001). Treatment was safe and well tolerated. The results of our pilot study suggest that application of fenticonazole nitrate 1 g intravaginal ovules on 2 alternate days is a suitable first-line treatment of vulvovaginitis with acceptable broad-spectrum efficacy against the most commonly involved pathogens and with a low rate of early relapse, reserving antibiotics for patients with treatment failure or relapse of infection. Our results should encourage further examination of this approach in larger and well controlled clinical trials.

A Group Neighborhood Average Clock Synchronization Protocol for Wireless Sensor Networks

PubMed Central

Lin, Lin; Ma, Shiwei; Ma, Maode

2014-01-01

Clock synchronization is a very important issue for the applications of wireless sensor networks. The sensors need to keep a strict clock so that users can know exactly what happens in the monitoring area at the same time. This paper proposes a novel internal distributed clock synchronization solution using group neighborhood average. Each sensor node collects the offset and skew rate of the neighbors. Group averaging of offset and skew rate value are calculated instead of conventional point-to-point averaging method. The sensor node then returns compensated value back to the neighbors. The propagation delay is considered and compensated. The analytical analysis of offset and skew compensation is presented. Simulation results validate the effectiveness of the protocol and reveal that the protocol allows sensor networks to quickly establish a consensus clock and maintain a small deviation from the consensus clock. PMID:25120163

Enhancing Time Synchronization Support in Wireless Sensor Networks

PubMed Central

Tavares Bruscato, Leandro; Heimfarth, Tales; Pignaton de Freitas, Edison

2017-01-01

With the emerging Internet of Things (IoT) technology becoming reality, a number of applications are being proposed. Several of these applications are highly dependent on wireless sensor networks (WSN) to acquire data from the surrounding environment. In order to be really useful for most of applications, the acquired data must be coherent in terms of the time in which they are acquired, which implies that the entire sensor network presents a certain level of time synchronization. Moreover, to efficiently exchange and forward data, many communication protocols used in WSN rely also on time synchronization among the sensor nodes. Observing the importance in complying with this need for time synchronization, this work focuses on the second synchronization problem, proposing, implementing and testing a time synchronization service for low-power WSN using low frequency real-time clocks in each node. To implement this service, three algorithms based on different strategies are proposed: one based on an auto-correction approach, the second based on a prediction mechanism, while the third uses an analytical correction mechanism. Their goal is the same, i.e., to make the clocks of the sensor nodes converge as quickly as possible and then to keep them most similar as possible. This goal comes along with the requirement to keep low energy consumption. Differently from other works in the literature, the proposal here is independent of any specific protocol, i.e., it may be adapted to be used in different protocols. Moreover, it explores the minimum number of synchronization messages by means of a smart clock update strategy, allowing the trade-off between the desired level of synchronization and the associated energy consumption. Experimental results, which includes data acquired from simulations and testbed deployments, provide evidence of the success in meeting this goal, as well as providing means to compare these three approaches considering the best synchronization results and their costs in terms of energy consumption. PMID:29261113

Enhancing Time Synchronization Support in Wireless Sensor Networks.

PubMed

Tavares Bruscato, Leandro; Heimfarth, Tales; Pignaton de Freitas, Edison

2017-12-20

With the emerging Internet of Things (IoT) technology becoming reality, a number of applications are being proposed. Several of these applications are highly dependent on wireless sensor networks (WSN) to acquire data from the surrounding environment. In order to be really useful for most of applications, the acquired data must be coherent in terms of the time in which they are acquired, which implies that the entire sensor network presents a certain level of time synchronization. Moreover, to efficiently exchange and forward data, many communication protocols used in WSN rely also on time synchronization among the sensor nodes. Observing the importance in complying with this need for time synchronization, this work focuses on the second synchronization problem, proposing, implementing and testing a time synchronization service for low-power WSN using low frequency real-time clocks in each node. To implement this service, three algorithms based on different strategies are proposed: one based on an auto-correction approach, the second based on a prediction mechanism, while the third uses an analytical correction mechanism. Their goal is the same, i.e., to make the clocks of the sensor nodes converge as quickly as possible and then to keep them most similar as possible. This goal comes along with the requirement to keep low energy consumption. Differently from other works in the literature, the proposal here is independent of any specific protocol, i.e., it may be adapted to be used in different protocols. Moreover, it explores the minimum number of synchronization messages by means of a smart clock update strategy, allowing the trade-off between the desired level of synchronization and the associated energy consumption. Experimental results, which includes data acquired from simulations and testbed deployments, provide evidence of the success in meeting this goal, as well as providing means to compare these three approaches considering the best synchronization results and their costs in terms of energy consumption.

A simple, effective media access protocol system for integrated, high data rate networks

NASA Technical Reports Server (NTRS)

Foudriat, E. C.; Maly, K.; Overstreet, C. M.; Khanna, S.; Zhang, L.

1992-01-01

The operation and performance of a dual media access protocol for integrated, gigabit networks are described. Unlike other dual protocols, each protocol supports a different class of traffic. The Carrier Sensed Multiple Access-Ring Network (CSMA/RN) protocol and the Circulating Reservation Packet (CRP) protocol support asynchronous and synchronous traffic, respectively. The two protocols operate with minimal impact upon each other. Performance information demonstrates that they support a complete range of integrated traffic loads, do not require call setup/termination or a special node for synchronous traffic control, and provide effective pre-use and recovery. The CRP also provides guaranteed access and fairness control for the asynchronous system. The paper demonstrates that the CSMA-CRP system fulfills many of the requirements for gigabit LAN-MAN networks most effectively and simply. To accomplish this, CSMA-CRP features are compared against similar ring and bus systems, such as Cambridge Fast Ring, Metaring, Cyclic Reservation Multiple Access, and Distributed Dual Queue Data Bus (DQDB).

Host-Parasite Interactions from the Inside: Plant Reproductive Ontogeny Drives Specialization in Parasitic Insects.

PubMed

Boivin, Thomas; Gidoin, Cindy; von Aderkas, Patrick; Safrana, Jonathan; Candau, Jean-Noël; Chalon, Alain; Sondo, Marion; El Maâtaoui, Mohamed

2015-01-01

Host plant interactions are likely key drivers of evolutionary processes involved in the diversification of phytophagous insects. Granivory has received substantial attention for its crucial role in shaping the interaction between plants and their seed parasites, but fine-scale mechanisms explaining the role of host plant reproductive biology on specialization of seed parasites remain poorly described. In a comparative approach using plant histological techniques, we tested the hypotheses that different seed parasite species synchronize their life cycles to specific stages in seed development, and that the stage they target depends on major differences in seed development programs. In a pinaceous system, seed storage products are initiated before ovule fertilization and the wasps target the ovule's nucellus during megagametogenesis, a stage at which larvae may benefit from the by-products derived from both secreting cells and dying nucellar cells. In a cupressaceous system, oviposition activity peaks later, during embryogenesis, and the wasps target the ovule's megagametophyte where larvae may benefit from cell disintegration during embryogenesis. Our cytohistological approach shows for the first time how, despite divergent oviposition targets, different parasite species share a common strategy that consists of first competing for nutrients with developing plant structures, and then consuming these developed structures to complete their development. Our results support the prediction that seed developmental program is an axis for specialization in seed parasites, and that it could be an important parameter in models of their ecological and taxonomic divergence. This study provides the basis for further investigating the possibility of the link between plant ontogeny and pre-dispersal seed parasitism.

Effects of progestagens and prostaglandin analogues on ovarian function and embryo viability in sheep.

PubMed

Gonzalez-Bulnes, A; Veiga-Lopez, A; Garcia, P; Garcia-Garcia, R M; Ariznavarreta, C; Sanchez, M A; Tresguerres, J A F; Cocero, M J; Flores, J M

2005-06-01

Current study assessed differences in the response of sheep to estrus synchronization either by the administration of two doses of prostaglandin or by the insertion of an intravaginal progestagen sponge. The preovulatory follicular dynamics and estradiol secretion, the ovulatory response and progesterone secretion and the number and quality of embryos were studied in 27 ewes treated with two doses of 100 microg of cloprostenol, 10 days apart, and in 29 sheep treated with progestagen sponges for 14 days. Percentage of sheep responding to the synchronization treatments with signs of estrus behaviour was similar between both groups (81.5% versus 72.4%, respectively). The use of progestagen resulted in a higher diameter of the largest follicle (6.6+/-0.2 versus 5.9+/-0.2, P<0.05), and a lower number of small (6.7+/-0.3 versus 9.6+/-0.4, P<0.005) and total follicles (10.3+/-0.3 versus 12.9+/-0.4, P<0.005). However, mean plasma estradiol concentration during the follicular phase was higher in cloprostenol treated sheep (P<0.005). The mean ovulation rate was similar in both treatments (1.7+/-0.2 versus 1.7+/-0.3), but progesterone concentration during the early luteal phase was again higher in sheep treated with cloprostenol (P<0.05). The mean number of retrieved oocytes/embryos was very similar in both treatments (1.2+/-0.2 versus 1.4+/-0.2) and showed similar fertilization rates (70.6% versus 66.7%), but, although differences did not reach statistical significance, final viability rate was higher in cloprostenol than in progestagen treated ewes (58.9% versus 46.1%, P=0.07). Current results give new evidences supporting the negative effects of progestagens on the functionality of ovulatory follicles and support the development of new protocols for assisted reproduction including the use of prostaglandin analogues.

Synchronized ovulation for first insemination improves reproductive performance and reduces cost per pregnancy in dairy heifers.

PubMed

Silva, T V; Lima, F S; Thatcher, W W; Santos, J E P

2015-11-01

The objectives were to evaluate the effects of synchronizing estrus and ovulation to implement a timed artificial insemination (AI) at first insemination on reproductive performance and cost per pregnancy in dairy heifers. Six hundred eleven Holsteins heifers at approximately 400 d of age from 3 farms were enrolled in the study. Six days before moving to the breeding pens, heifers were allocated randomly to AI after detected estrus from study d 0 to 84 (CON, n=306), or to timed AI for first AI followed by detected estrus for the remainder of the 84-d study (TAI, n=305). Heifers receiving TAI were enrolled in the 5-d timed AI protocol on study d -6 (d -6, GnRH and a progesterone insert; d -1, PGF2α and insert removal; d 0, PGF2α; d 2, GnRH + AI), and they were allowed to be bred the day before scheduled timed AI if detected in estrus. Starting on study d 0, estrus was detected daily. Heifers in estrus were inseminated on the same morning as detected estrus. Control heifers not inseminated by study d 7 received PGF2α and this treatment was repeated every 2 wk until AI. The study lasted 84 d to allow a period of breeding equivalent to four 21-d estrous cycles. A herd budget accounting for inputs for both treatments was created to determine the cost per pregnancy. Sensitivity analysis compared economic differences between the 2 treatments under different input scenarios when detection of estrus after the first AI varied from 50 to 80%. Interval to first AI was 8 d shorter for TAI than for CON. Pregnancy at first AI did not differ between treatments (CON=58.3 vs. TAI=62.8%). In contrast, TAI increased pregnancy per AI (P/AI) compared with CON in heifers inseminated with sex-sorted semen (CON=31.6 vs. TAI=54.8%). The 21-d cycle insemination rate was greater for TAI (91.4%) than for CON (82.4%), even when evaluated after the first 21 d in the study (CON=68.2 vs. TAI=77.1%). The increased insemination rate improved the 21-d cycle pregnancy rate from 47.9% in CON to 57.2% in TAI heifers. In fact, the hazard of pregnancy was 60% greater for TAI than CON. The increased pregnancy rate in TAI reduced the median days to pregnancy by 12 d (CON=2.0 vs. TAI=14.0) and increased the proportion of pregnant heifers by 6.3 percentage points by study d 84 (CON=85.2 vs. TAI=91.5%). The cost per pregnancy was $17.00 less for TAI than CON. The sensitivity analysis indicated that TAI was economically more advantageous to produce a pregnancy compared with CON. Only when insemination rate after the first 21 d of breeding was very high and P/AI was relatively low did the cost per pregnancy become similar for the 2 treatments. Collectively, inseminating all heifers within 2 d of breeding with the 5-d timed AI protocol maintains P/AI, improves pregnancy rate, and reduces cost per pregnancy compared with insemination after detected estrus. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Dynamics of neural cryptography

NASA Astrophysics Data System (ADS)

Ruttor, Andreas; Kinzel, Wolfgang; Kanter, Ido

2007-05-01

Synchronization of neural networks has been used for public channel protocols in cryptography. In the case of tree parity machines the dynamics of both bidirectional synchronization and unidirectional learning is driven by attractive and repulsive stochastic forces. Thus it can be described well by a random walk model for the overlap between participating neural networks. For that purpose transition probabilities and scaling laws for the step sizes are derived analytically. Both these calculations as well as numerical simulations show that bidirectional interaction leads to full synchronization on average. In contrast, successful learning is only possible by means of fluctuations. Consequently, synchronization is much faster than learning, which is essential for the security of the neural key-exchange protocol. However, this qualitative difference between bidirectional and unidirectional interaction vanishes if tree parity machines with more than three hidden units are used, so that those neural networks are not suitable for neural cryptography. In addition, the effective number of keys which can be generated by the neural key-exchange protocol is calculated using the entropy of the weight distribution. As this quantity increases exponentially with the system size, brute-force attacks on neural cryptography can easily be made unfeasible.

Dynamics of neural cryptography.

PubMed

Ruttor, Andreas; Kinzel, Wolfgang; Kanter, Ido

2007-05-01

Synchronization of neural networks has been used for public channel protocols in cryptography. In the case of tree parity machines the dynamics of both bidirectional synchronization and unidirectional learning is driven by attractive and repulsive stochastic forces. Thus it can be described well by a random walk model for the overlap between participating neural networks. For that purpose transition probabilities and scaling laws for the step sizes are derived analytically. Both these calculations as well as numerical simulations show that bidirectional interaction leads to full synchronization on average. In contrast, successful learning is only possible by means of fluctuations. Consequently, synchronization is much faster than learning, which is essential for the security of the neural key-exchange protocol. However, this qualitative difference between bidirectional and unidirectional interaction vanishes if tree parity machines with more than three hidden units are used, so that those neural networks are not suitable for neural cryptography. In addition, the effective number of keys which can be generated by the neural key-exchange protocol is calculated using the entropy of the weight distribution. As this quantity increases exponentially with the system size, brute-force attacks on neural cryptography can easily be made unfeasible.

Dynamics of neural cryptography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ruttor, Andreas; Kinzel, Wolfgang; Kanter, Ido

2007-05-15

Synchronization of neural networks has been used for public channel protocols in cryptography. In the case of tree parity machines the dynamics of both bidirectional synchronization and unidirectional learning is driven by attractive and repulsive stochastic forces. Thus it can be described well by a random walk model for the overlap between participating neural networks. For that purpose transition probabilities and scaling laws for the step sizes are derived analytically. Both these calculations as well as numerical simulations show that bidirectional interaction leads to full synchronization on average. In contrast, successful learning is only possible by means of fluctuations. Consequently,more » synchronization is much faster than learning, which is essential for the security of the neural key-exchange protocol. However, this qualitative difference between bidirectional and unidirectional interaction vanishes if tree parity machines with more than three hidden units are used, so that those neural networks are not suitable for neural cryptography. In addition, the effective number of keys which can be generated by the neural key-exchange protocol is calculated using the entropy of the weight distribution. As this quantity increases exponentially with the system size, brute-force attacks on neural cryptography can easily be made unfeasible.« less

Effects of physiological and/or disease status on the response of postpartum dairy cows to synchronization of estrus using an intravaginal progesterone device.

PubMed

McNally, Julie C; Crowe, Mark A; Roche, James F; Beltman, Marijke E

2014-12-01

Progesterone treatments are used to increase submission rates in postpartum dairy cows; however, in many cases the protocol is used as a blanket therapy for all cows without regard for physiological or disease state. The objective of this study was to identify the physiological or disease classes of cows that respond well (or not) to synchronization of estrus via progesterone. Dairy cows (n = 402) were monitored peri and postpartum to establish their physiological or disease status. Animals were classified as having negative energy balance, clinical lameness, uterine infection (UI), anovulatory anestrus, high somatic cell counts, and healthy (H). Blood samples were collected at five different time points and analyzed for metabolites. All animals received an 8-day controlled internal drug release protocol, which included GnRH at insertion and PGF2α the day before removal. Response to the protocol was determined by visual observation of estrus synchronization. Conception rate was determined by ultrasonography between Days 32 and 35 after artificial insemination. Animals without UI were 1.9 times more likely to respond and two times more likely to be confirmed pregnant than those with UI. There was no relationship between negative energy balance and clinical lameness in the visual estrous response, but both conditions were associated with reduced conception rates. Dairy cows in anovulatory anestrus responded successfully to the protocol in both estrous response and conception rates. High glutathione peroxidase concentrations had a positive effect on conception rates, whereas high non-esterified fatty acids and beta-hydroxybutyrate had a negative effect on the estrous response. In conclusion, disease and physiological states of dairy cows determined the response to progesterone-based synchronization. The more disease or physiological problems the cows had, the lower the estrous response and conception rates; cows with these problems were not ideal candidates for synchronization. Both anestrus and healthy dairy cows were good responders to progesterone-based synchronization. Copyright © 2014 Elsevier Inc. All rights reserved.

Homomorphic Filtering for Improving Time Synchronization in Wireless Networks

PubMed Central

Castillo-Secilla, José María; Palomares, José Manuel; León, Fernando; Olivares, Joaquín

2017-01-01

Wireless sensor networks are used to sample the environment in a distributed way. Therefore, it is mandatory for all of the measurements to be tightly synchronized in order to guarantee that every sensor is sampling the environment at the exact same instant of time. The synchronization drift gets bigger in environments suffering from temperature variations. Thus, this work is focused on improving time synchronization under deployments with temperature variations. The working hypothesis demonstrated in this work is that the clock skew of two nodes (the ratio of the real frequencies of the oscillators) is composed of a multiplicative combination of two main components: the clock skew due to the variations between the cut of the crystal of each oscillator and the clock skew due to the different temperatures affecting the nodes. By applying a nonlinear filtering, the homomorphic filtering, both components are separated in an effective way. A correction factor based on temperature, which can be applied to any synchronization protocol, is proposed. For testing it, an improvement of the FTSP synchronization protocol has been developed and physically tested under temperature variation scenarios using TelosB motes flashed with the IEEE 802.15.4 implementation supplied by TinyOS. PMID:28425955

Homomorphic Filtering for Improving Time Synchronization in Wireless Networks.

PubMed

Castillo-Secilla, José María; Palomares, José Manuel; León, Fernando; Olivares, Joaquín

2017-04-20

Wireless sensor networks are used to sample the environment in a distributed way. Therefore, it is mandatory for all of the measurements to be tightly synchronized in order to guarantee that every sensor is sampling the environment at the exact same instant of time. The synchronization drift gets bigger in environments suffering from temperature variations. Thus, this work is focused on improving time synchronization under deployments with temperature variations. The working hypothesis demonstrated in this work is that the clock skew of two nodes (the ratio of the real frequencies of the oscillators) is composed of a multiplicative combination of two main components: the clock skew due to the variations between the cut of the crystal of each oscillator and the clock skew due to the different temperatures affecting the nodes. By applying a nonlinear filtering, the homomorphic filtering, both components are separated in an effective way. A correction factor based on temperature, which can be applied to any synchronization protocol, is proposed. For testing it, an improvement of the FTSP synchronization protocol has been developed and physically tested under temperature variation scenarios using TelosB motes flashed with the IEEE 802.15.4 implementation supplied by TinyOS.

Influence of beta-carotene on fertility in rabbits when using embryo transfer programs.

PubMed

Besenfelder, U; Solti, L; Seregi, J; Brem, G

1993-05-01

The effect of beta-carotene on reproduction traits in rabbits was studied in 509 (superovulated and normally ovulated) donors and 239 recipients by using embryo/gene transfer performed at 2 different locations. All of the bucks and the half of the females were fed a diet supplemented with 40 mg synthetic beta-carotene (Rovimix((R)))/kg feed. Embryos at the pronucleus stage were collected 19 to 21 hours after induction of ovulation with human chorionic gonadotropin (hCG); they were then microinjected into the male pronucleus and transferred to synchronized recipients. Data were obtained from the time when the donors and recipients were caged, until the pups resulting from the embryo transfers were weaned. Supplemented beta-carotene did not affect most of the 30 traits that were analyzed. However superovulated donors in Project 2 that received the beta-carotene enriched diet had a 14% lighter ovary weight (P<0.05) and less than half of the oocytes were unfertilized (P<0.05). In Project 1 (beta-carotene group) there was a greater number of pups born (36%, P<0.05) and more of these pups were born alive (53%, P<0.05).

Successful attack on permutation-parity-machine-based neural cryptography.

PubMed

Seoane, Luís F; Ruttor, Andreas

2012-02-01

An algorithm is presented which implements a probabilistic attack on the key-exchange protocol based on permutation parity machines. Instead of imitating the synchronization of the communicating partners, the strategy consists of a Monte Carlo method to sample the space of possible weights during inner rounds and an analytic approach to convey the extracted information from one outer round to the next one. The results show that the protocol under attack fails to synchronize faster than an eavesdropper using this algorithm.

Update on Multiple Ovulations in Dairy Cattle

PubMed Central

Macmillan, Kira; Kastelic, John P.

2018-01-01

Simple Summary Multiple ovulations (MOV) in cattle can lead to twin pregnancies, which negatively affects the health, production, and reproduction of cows. Despite many studies, the causal mechanisms behind MOV are still not well understood. There is a general agreement that MOV are more likely during periods of low progesterone (P4), which may increase the luteinizing hormone (LH) release at the time of selection, resulting in more than one follicle becoming dominant. The MOV rate also increases in older cows and when the selection of a dominant follicle occurs concurrently with a high milk yield. Additional risk factors for MOV are ovarian cysts, diet, season, and genetics. A better understanding of the mechanisms underlying MOV may help to mitigate twinning, perhaps through the appropriate reproductive management protocols or genetic selection. Abstract This review updates the causal mechanisms and risk factors for multiple ovulations (MOV) in cattle. Clearly, MOV can lead to twin pregnancies, which negatively affects the health, production, and reproduction of cows. Therefore, a better understanding of the factors causing MOV may help to reduce twinning. Multiple ovulations occur after two or more follicles deviate and achieve codominance. The MOV rate is influenced by a complex network of hormones. For example, MOV is more common during periods of low progesterone (P4), that is, in anovulatory cattle or when luteolysis coincides with the selection of the future ovulatory follicle. There is also strong evidence for the luteinizing hormone (LH) being the primary factor leading to codominance, as high P4 concentrations suppress the transient LH surges and can reduce the ovulation rate in cattle or even inhibit deviation. Rates of MOV are increased in older and higher-producing dairy cows. Increased milk production and dry matter intake (DMI) increases hormone clearance, including P4; however, the association between milk yield and MOV has not been consistent. Additional risk factors for MOV include ovarian cysts, diet, season, and genetics. PMID:29695075

Relationship Between the Menstrual Cycle and Timing of Ovulation Revealed by New Protocols: Analysis of Data from a Self-Tracking Health App.

PubMed

Sohda, Satoshi; Suzuki, Kenta; Igari, Ichiro

2017-11-27

There are many mobile phone apps aimed at helping women map their ovulation and menstrual cycles and facilitating successful conception (or avoiding pregnancy). These apps usually ask users to input various biological features and have accumulated the menstrual cycle data of a vast number of women. The purpose of our study was to clarify how the data obtained from a self-tracking health app for female mobile phone users can be used to improve the accuracy of prediction of the date of next ovulation. Using the data of 7043 women who had reliable menstrual and ovulation records out of 8,000,000 users of a mobile phone app of a health care service, we analyzed the relationship between the menstrual cycle length, follicular phase length, and luteal phase length. Then we fitted a linear function to the relationship between the length of the menstrual cycle and timing of ovulation and compared it with the existing calendar-based methods. The correlation between the length of the menstrual cycle and the length of the follicular phase was stronger than the correlation between the length of the menstrual cycle and the length of the luteal phase, and there was a positive correlation between the lengths of past and future menstrual cycles. A strong positive correlation was also found between the mean length of past cycles and the length of the follicular phase. The correlation between the mean cycle length and the luteal phase length was also statistically significant. In most of the subjects, our method (ie, the calendar-based method based on the optimized function) outperformed the Ogino method of predicting the next ovulation date. Our method also outperformed the ovulation date prediction method that assumes the middle day of a mean menstrual cycle as the date of the next ovulation. The large number of subjects allowed us to capture the relationships between the lengths of the menstrual cycle, follicular phase, and luteal phase in more detail than previous studies. We then demonstrated how the present calendar methods could be improved by the better grouping of women. This study suggested that even without integrating various biological metrics, the dataset collected by a self-tracking app can be used to develop formulas that predict the ovulation day when the data are aggregated. Because the method that we developed requires data only on the first day of menstruation, it would be the best option for couples during the early stages of their attempt to have a baby or for those who want to avoid the cost associated with other methods. Moreover, the result will be the baseline for more advanced methods that integrate other biological metrics. ©Satoshi Sohda, Kenta Suzuki, Ichiro Igari. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 27.11.2017.

Low Latency MAC Protocol in Wireless Sensor Networks Using Timing Offset

NASA Astrophysics Data System (ADS)

Choi, Seung Sik

This paper proposes a low latency MAC protocol that can be used in sensor networks. To extend the lifetime of sensor nodes, the conventional solution is to synchronize active/sleep periods of all sensor nodes. However, due to these synchronized sensor nodes, packets in the intermediate nodes must wait until the next node wakes up before it can forward a packet. This induces a large delay in sensor nodes. To solve this latency problem, a clustered sensor network which uses two types of sensor nodes and layered architecture is considered. Clustered heads in each cluster are synchronized with different timing offsets to reduce the sleep delay. Using this concept, the latency problem can be solved and more efficient power usage can be obtained.

Ovulation induction: a mini review.

PubMed

Messinis, Ioannis E

2005-10-01

Ovulation induction is the method for treating anovulatory infertility. For patients with hypogonadotrophic hypogonadism, the treatment involves administration of both FSH and LH, while HCG is injected for follicle rupture. Pulsatile GnRH has the same effectiveness as gonadotrophins and the advantage of the low multiple pregnancy rate. In polycystic ovary syndrome (PCOS), the first treatment choice is clomiphene citrate. With this drug, in properly selected patients, the cumulative pregnancy rate approaches that of normal women. Low-dose protocols of FSH are the second line of treatment, effective in inducing monofollicular development. Laparoscopic ovarian drilling can be an alternative but not as a first choice treatment in clomiphene-resistant patients. Other treatments, such as pulsatile GnRH and GnRH agonists, are hardly used today in PCOS. However, in obese women with PCOS, weight loss and exercise should be recommended as the first line of therapy. Newer agents including aromatase inhibitors and insulin sensitizers, although promising, need further evaluation.

Distributed Dynamic Host Configuration Protocol (D2HCP)

PubMed Central

Villalba, Luis Javier García; Matesanz, Julián García; Orozco, Ana Lucila Sandoval; Díaz, José Duván Márquez

2011-01-01

Mobile Ad Hoc Networks (MANETs) are multihop wireless networks of mobile nodes without any fixed or preexisting infrastructure. The topology of these networks can change randomly due to the unpredictable mobility of nodes and their propagation characteristics. In most networks, including MANETs, each node needs a unique identifier to communicate. This work presents a distributed protocol for dynamic node IP address assignment in MANETs. Nodes of a MANET synchronize from time to time to maintain a record of IP address assignments in the entire network and detect any IP address leaks. The proposed stateful autoconfiguration scheme uses the OLSR proactive routing protocol for synchronization and guarantees unique IP addresses under a variety of network conditions, including message losses and network partitioning. Simulation results show that the protocol incurs low latency and communication overhead for IP address assignment. PMID:22163856

Distributed Dynamic Host Configuration Protocol (D2HCP).

PubMed

Villalba, Luis Javier García; Matesanz, Julián García; Orozco, Ana Lucila Sandoval; Díaz, José Duván Márquez

2011-01-01

Mobile Ad Hoc Networks (MANETs) are multihop wireless networks of mobile nodes without any fixed or preexisting infrastructure. The topology of these networks can change randomly due to the unpredictable mobility of nodes and their propagation characteristics. In most networks, including MANETs, each node needs a unique identifier to communicate. This work presents a distributed protocol for dynamic node IP address assignment in MANETs. Nodes of a MANET synchronize from time to time to maintain a record of IP address assignments in the entire network and detect any IP address leaks. The proposed stateful autoconfiguration scheme uses the OLSR proactive routing protocol for synchronization and guarantees unique IP addresses under a variety of network conditions, including message losses and network partitioning. Simulation results show that the protocol incurs low latency and communication overhead for IP address assignment.

Selection of G1 Phase Yeast Cells for Synchronous Meiosis and Sporulation.

PubMed

Stuart, David T

2017-01-01

Centrifugal elutriation is a procedure that allows the fractionation of cell populations based upon their size and shape. This allows cells in distinct cell cycle stages can be captured from an asynchronous population. The technique is particularly helpful when performing an experiment to monitor the progression of cells through the cell cycle or meiosis. Yeast sporulation like gametogenesis in other eukaryotes initiates from the G1 phase of the cell cycle. Conveniently, S. cerevisiae arrest in G1 phase when starved for nutrients and so withdrawal of nitrogen and glucose allows cells to abandon vegetative growth in G1 phase before initiating the sporulation program. This simple starvation protocol yields a partial synchronization that has been used extensively in studies of progression through meiosis and sporulation. By using centrifugal elutriation it is possible to isolate a homogeneous population of G1 phase cells and induce them to sporulate synchronously, which is beneficial for investigating progression through meiosis and sporulation. An additionally benefit of this protocol is that cell populations can be isolated based upon size and both large and small cell populations can be tested for progression through meiosis and sporulation. Here we present a protocol for purification of G1 phase diploid cells for examining synchronous progression through meiosis and sporulation.

Throughput analysis of the IEEE 802.4 token bus standard under heavy load

NASA Technical Reports Server (NTRS)

Pang, Joseph; Tobagi, Fouad

1987-01-01

It has become clear in the last few years that there is a trend towards integrated digital services. Parallel to the development of public Integrated Services Digital Network (ISDN) is service integration in the local area (e.g., a campus, a building, an aircraft). The types of services to be integrated depend very much on the specific local environment. However, applications tend to generate data traffic belonging to one of two classes. According to IEEE 802.4 terminology, the first major class of traffic is termed synchronous, such as packetized voice and data generated from other applications with real-time constraints, and the second class is called asynchronous which includes most computer data traffic such as file transfer or facsimile. The IEEE 802.4 token bus protocol which was designed to support both synchronous and asynchronous traffic is examined. The protocol is basically a timer-controlled token bus access scheme. By a suitable choice of the design parameters, it can be shown that access delay is bounded for synchronous traffic. As well, the bandwidth allocated to asynchronous traffic can be controlled. A throughput analysis of the protocol under heavy load with constant channel occupation of synchronous traffic and constant token-passing times is presented.

MTP: An atomic multicast transport protocol

NASA Technical Reports Server (NTRS)

Freier, Alan O.; Marzullo, Keith

1990-01-01

Multicast transport protocol (MTP); a reliable transport protocol that utilizes the multicast strategy of applicable lower layer network architectures is described. In addition to transporting data reliably and efficiently, MTP provides the client synchronization necessary for agreement on the receipt of data and the joining of the group of communicants.

Communication protocol in chassis detecting wireless transmission system based on WiFi

USDA-ARS?s Scientific Manuscript database

In chassis detecting wireless transmission system, the wireless network communication protocol plays a key role in the information exchange and synchronization between the host and chassis PDA. This paper presents a wireless network transmission protocol based on TCP/IP which makes the rules of info...

DE-Sync: A Doppler-Enhanced Time Synchronization for Mobile Underwater Sensor Networks.

PubMed

Zhou, Feng; Wang, Qi; Nie, DongHu; Qiao, Gang

2018-05-25

Time synchronization is the foundation of cooperative work among nodes of underwater sensor networks; it takes a critical role in the research and application of underwater sensor networks. Although numerous time synchronization protocols have been proposed for terrestrial wireless sensor networks, they cannot be directly applied to underwater sensor networks. This is because most of them typically assume that the propagation delay among sensor nodes is negligible, which is not the case in underwater sensor networks. Time synchronization is mainly affected by a long propagation delay among sensor nodes due to the low propagation speed of acoustic signals. Furthermore, sensor nodes in underwater tend to experience some degree of mobility due to wind or ocean current, or some other nodes are on self-propelled vehicles, such as autonomous underwater vehicles (AUVs). In this paper, we propose a Doppler-enhanced time synchronization scheme for mobile underwater sensor networks, called DE-Sync. Our new scheme considers the effect of the clock skew during the process of estimating the Doppler scale factor and directly substitutes the Doppler scale factor into linear regression to achieve the estimation of the clock skew and offset. Simulation results show that DE-Sync outperforms existing time synchronization protocols in both accuracy and energy efficiency.

Transcriptomic Signature of the SHATTERPROOF2 Expression Domain Reveals the Meristematic Nature of Arabidopsis Gynoecial Medial Domain1[OPEN

PubMed Central

Villarino, Gonzalo H.; Hu, Qiwen; Flores-Vergara, Miguel; Sehra, Bhupinder; Brumos, Javier; Stepanova, Anna N.; Sundberg, Eva; Heber, Steffen

2016-01-01

Plant meristems, like animal stem cell niches, maintain a pool of multipotent, undifferentiated cells that divide and differentiate to give rise to organs. In Arabidopsis (Arabidopsis thaliana), the carpel margin meristem is a vital meristematic structure that generates ovules from the medial domain of the gynoecium, the female floral reproductive structure. The molecular mechanisms that specify this meristematic region and regulate its organogenic potential are poorly understood. Here, we present a novel approach to analyze the transcriptional signature of the medial domain of the Arabidopsis gynoecium, highlighting the developmental stages that immediately proceed ovule initiation, the earliest stages of seed development. Using a floral synchronization system and a SHATTERPROOF2 (SHP2) domain-specific reporter, paired with FACS and RNA sequencing, we assayed the transcriptome of the gynoecial medial domain with temporal and spatial precision. This analysis reveals a set of genes that are differentially expressed within the SHP2 expression domain, including genes that have been shown previously to function during the development of medial domain-derived structures, including the ovules, thus validating our approach. Global analyses of the transcriptomic data set indicate a similarity of the pSHP2-expressing cell population to previously characterized meristematic domains, further supporting the meristematic nature of this gynoecial tissue. Our method identifies additional genes including novel isoforms, cis-natural antisense transcripts, and a previously unrecognized member of the REPRODUCTIVE MERISTEM family of transcriptional regulators that are potential novel regulators of medial domain development. This data set provides genome-wide transcriptional insight into the development of the carpel margin meristem in Arabidopsis. PMID:26983993

Role of myometrial activity in sperm transport through the genital tract and in fertilization in sows.

PubMed

Langendijk, P; Bouwman, E G; Kidson, A; Kirkwood, R N; Soede, N M; Kemp, B

2002-05-01

The effects of stimulation and suppression of uterine contractility at about the time of insemination on sperm distribution and fertilization in multiparous sows are described. For assessment of fertilization, sows were inseminated about 28 h before (synchronized) ovulation and killed at day 5 after ovulation (n = 53). For assessment of sperm distribution, sows were inseminated about 20 h before expected ovulation and were killed 12 h later (n = 26). At 10 min before insemination, sows received an intrauterine infusion of one of three solutions: (i) saline (control); (ii) 0.60 mg clenbuterol hydrochloride to suppress contractility; or (iii) 1 mg cloprostenol to stimulate contractility. Both clenbuterol and cloprostenol reduced median fertilization rate (P < 0.05) and median number of accessory sperm cells (P < 0.05). Distribution of sperm cells was also affected by treatments. Clenbuterol increased, and cloprostenol decreased, the number of sperm cells (P < 0.05) in the proximal 20 cm of the uterine horn and in the uterotubal junction. In addition, clenbuterol tended to increase and cloprostenol tended to decrease the number of sperm cells in the isthmus, although these effects were not significant. However, relative to the number of sperm cells in the uterus, clenbuterol treatment reduced the number of sperm cells in the uterotubal junction and oviduct, in contrast to cloprostenol. Cloprostenol increased the reflux of semen during insemination. It is hypothesized that suppression of uterine contractility increases transuterine transport time, reducing the ability of sperm cells to enter the uterotubal junction and the oviduct. Stimulation of uterine contractility above a certain level probably increases reflux and impedes transuterine transport of sufficient numbers of sperm cells.

Efficacy of Floor Control Protocols in Distributed Multimedia Collaboration

DTIC Science & Technology

1999-01-01

advanced consider- ably, support for such controlled group interaction, particularly for applications geared towards synchronous and wide-area groupwork ...transaction-oriented collaboration, and synchronous groupwork is limited mostly to text and chatting. The JETS system [32] is a recent example for a Java-based

Measurement of Survival Time in Brachionus Rotifers: Synchronization of Maternal Conditions.

PubMed

Kaneko, Gen; Yoshinaga, Tatsuki; Gribble, Kristin E; Welch, David M; Ushio, Hideki

2016-07-22

Rotifers are microscopic cosmopolitan zooplankton used as models in ecotoxicological and aging studies due to their several advantages such as short lifespan, ease of culture, and parthenogenesis that enables clonal culture. However, caution is required when measuring their survival time as it is affected by maternal age and maternal feeding conditions. Here we provide a protocol for powerful and reproducible measurement of the survival time in Brachionus rotifers following a careful synchronization of culture conditions over several generations. Empirically, poor synchronization results in early mortality and a gradual decrease in survival rate, thus resulting in weak statistical power. Indeed, under such conditions, calorie restriction (CR) failed to significantly extend the lifespan of B. plicatilis although CR-induced longevity has been demonstrated with well-synchronized rotifer samples in past and present studies. This protocol is probably useful for other invertebrate models, including the fruitfly Drosophila melanogaster and the nematode Caenorhabditis elegans, because maternal age effects have also been reported in these species.

Measurement of Survival Time in Brachionus Rotifers: Synchronization of Maternal Conditions

PubMed Central

Kaneko, Gen; Yoshinaga, Tatsuki; Gribble, Kristin E.; Welch, David M.; Ushio, Hideki

2016-01-01

Rotifers are microscopic cosmopolitan zooplankton used as models in ecotoxicological and aging studies due to their several advantages such as short lifespan, ease of culture, and parthenogenesis that enables clonal culture. However, caution is required when measuring their survival time as it is affected by maternal age and maternal feeding conditions. Here we provide a protocol for powerful and reproducible measurement of the survival time in Brachionus rotifers following a careful synchronization of culture conditions over several generations. Empirically, poor synchronization results in early mortality and a gradual decrease in survival rate, thus resulting in weak statistical power. Indeed, under such conditions, calorie restriction (CR) failed to significantly extend the lifespan of B. plicatilis although CR-induced longevity has been demonstrated with well-synchronized rotifer samples in past and present studies. This protocol is probably useful for other invertebrate models, including the fruitfly Drosophila melanogaster and the nematode Caenorhabditis elegans, because maternal age effects have also been reported in these species. PMID:27500471

Mother-daughter in vitro fertilization triplet surrogate pregnancy.

PubMed

Michelow, M C; Bernstein, J; Jacobson, M J; McLoughlin, J L; Rubenstein, D; Hacking, A I; Preddy, S; Van der Wat, I J

1988-02-01

A successful triplet pregnancy has been established in a surrogate gestational mother following the transfer of five embryos fertilized in vitro. The oocytes were donated by her biological daughter, and the sperm obtained from the daughter's husband. The daughter's infertility followed a total abdominal hysterectomy performed for a postpartum hemorrhage as a result of a placenta accreta. Synchronization of both their menstrual cycles was obtained using oral contraceptive suppression for 2 months, followed by stimulation of both the surrogate gestational mother and her daughter such that embryo transfer would occur at least 48 hr after the surrogate gestational mother's own ovulation. This case raises a number of medical, social, psychological, and ethical issues.

High-throughput synchronization of mammalian cell cultures by spiral microfluidics.

PubMed

Lee, Wong Cheng; Bhagat, Ali Asgar S; Lim, Chwee Teck

2014-01-01

The development of mammalian cell cycle synchronization techniques has greatly advanced our understanding of many cellular regulatory events and mechanisms specific to different phases of the cell cycle. In this chapter, we describe a high-throughput microfluidic-based approach for cell cycle synchronization. By exploiting the relationship between cell size and its phase in the cell cycle, large numbers of synchronized cells can be obtained by size fractionation in a spiral microfluidic channel. Protocols for the synchronization of primary cells such as mesenchymal stem cells, and immortal cell lines such as Chinese hamster ovarian cells (CHO-CD36) and HeLa cells are provided as examples.

Sperm retention site and its influence on pronucleus stage evaluation following intracytoplasmic sperm injection.

PubMed

Negishi, Momoko; Yanaihara, Atsushi; Iwasaki, Shinji; Suzuki, Norio; Hasegawa, Junichi; Yorimitsu, Takeshi; Okai, Takashi

2007-09-01

Aim:  It has been suggested that the position of the sperm after intracytoplasmic sperm injection (ICSI) has an effect on the development and quality of the embryo. In this study, we retrospectively examined whether pronucleus stage evaluation used through clinical studies in recent years has relevance with regard to sperm location. Methods:  From 2003 to 2005, 1285 oocytes from 459 patients (average age: 36 years) were retrospectively analyzed. The 459 patients underwent ICSI because of fertilization disorders and oligozoospermia. Follicle stimulation was via either Clomid or the long protocol. Human chorionic gonadotropin was administered to induce ovulation and oocyte retrieval was conducted 35 h later. After confirming the presence of a polar body, we immobilized the ovum at the 6 o'clock position, introduced the injection pipette at the 3 o'clock position and carried out ICSI. Results:  When a sperm was located at a position that was opposite to the polar body, both classifications of Scott and Tesarik regarding embryo quality were distinctly low. Furthermore, a good embryo classification ensued when the sperm was located adjacent to the polar body. Conclusion:  The zone in which the sperm was located did not always correlate with embryo quality; however, our study suggested that sperm location affects the synchronization of the nucleolus. When carrying out ICSI, it is important to take into consideration the insertion point of the sperm. (Reprod Med Biol 2007; 6 : 171-174).

Reproductive performance of lactating dairy cows managed for first service using timed artificial insemination with or without detection of estrus using an activity-monitoring system.

PubMed

Fricke, P M; Giordano, J O; Valenza, A; Lopes, G; Amundson, M C; Carvalho, P D

2014-05-01

Lactating dairy cows (n=1,025) on a commercial dairy farm were randomly assigned at 10 ± 3 d in milk (DIM) to 1 of 3 treatments for submitting cows to first artificial insemination (AI) and were fitted with activity-monitoring tags (Heatime; SCR Engineers Ltd., Netanya, Israel) at 24 ± 3 DIM. Cows (n=339) in treatment 1 were inseminated based on increased activity from the end of the voluntary waiting period (50 DIM) until submission to an Ovsynch protocol; cows without increased activity from 21 to 65 DIM began an Ovsynch protocol at 65 ± 3 DIM, whereas cows without increased activity from 21 to 50 DIM but not from 51 to 79 DIM began an Ovsynch protocol at 79 ± 3 DIM. Cows (n=340) in treatment 2 were inseminated based on activity after the second PGF2α injection of a Presynch-Ovsynch protocol at 50 DIM, and cows without increased activity began an Ovsynch protocol at 65 ± 3 DIM. Cows (n=346) in treatment 3 were monitored for activity after the second PGF2α injection of a Presynch-Ovsynch protocol, but all cows received timed AI (TAI) at 75 ± 3 DIM after completing the Presynch-Ovsynch protocol. The activity-monitoring system detected increased activity in 56, 69, and 70% of cows in treatments 1, 2, and 3, respectively. Treatment-2 cows had the fewest average days to first AI (62.5), treatment-3 cows had the most average days to first AI (74.9), and treatment-1 cows had intermediate average days to first AI (67.4). Treatment-1 and -2 cows in which inseminations occurred as a combination between increased activity and TAI had fewer overall pregnancies per AI (P/AI) 35 d after AI (32% for both treatments) compared with treatment-3 cows, all of which received TAI after completing the Presynch-Ovsynch protocol (40%). Based on survival analysis, although the rate at which cows were inseminated differed among treatments, treatment did not affect the proportion of cows pregnant by 300 DIM. Thus, use of an activity-monitoring system to inseminate cows based on activity reduced days to first AI, whereas cows receiving 100% TAI after completing a Presynch-Ovsynch protocol had more P/AI. The trade-off between AI service rate and P/AI in the rate at which cows became pregnant was supported by an economic analysis in which the net present value ($/cow per year) differed by only $4 to $8 among treatments. We conclude that a variety of strategies using a combination of AI based on increased activity using an activity-monitoring system and synchronization of ovulation and TAI can be used to submit cows for first AI. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Model Checking a Self-Stabilizing Distributed Clock Synchronization Protocol for Arbitrary Digraphs

NASA Technical Reports Server (NTRS)

Malekpour, Mahyar R.

2011-01-01

This report presents the mechanical verification of a self-stabilizing distributed clock synchronization protocol for arbitrary digraphs in the absence of faults. This protocol does not rely on assumptions about the initial state of the system, other than the presence of at least one node, and no central clock or a centrally generated signal, pulse, or message is used. The system under study is an arbitrary, non-partitioned digraph ranging from fully connected to 1-connected networks of nodes while allowing for differences in the network elements. Nodes are anonymous, i.e., they do not have unique identities. There is no theoretical limit on the maximum number of participating nodes. The only constraint on the behavior of the node is that the interactions with other nodes are restricted to defined links and interfaces. This protocol deterministically converges within a time bound that is a linear function of the self-stabilization period.

Traffic placement policies for a multi-band network

NASA Technical Reports Server (NTRS)

Maly, Kurt J.; Foudriat, E. C.; Game, David; Mukkamala, R.; Overstreet, C. Michael

1990-01-01

Recently protocols were introduced that enable the integration of synchronous traffic (voice or video) and asynchronous traffic (data) and extend the size of local area networks without loss in speed or capacity. One of these is DRAMA, a multiband protocol based on broadband technology. It provides dynamic allocation of bandwidth among clusters of nodes in the total network. A number of traffic placement policies for such networks are proposed and evaluated. Metrics used for performance evaluation include average network access delay, degree of fairness of access among the nodes, and network throughput. The feasibility of the DRAMA protocol is established through simulation studies. DRAMA provides effective integration of synchronous and asychronous traffic due to its ability to separate traffic types. Under the suggested traffic placement policies, the DRAMA protocol is shown to handle diverse loads, mixes of traffic types, and numbers of nodes, as well as modifications to the network structure and momentary traffic overloads.

Inferences of body energy reserves on conception rate of suckled Zebu beef cows subjected to timed artificial insemination followed by natural mating.

PubMed

Ayres, H; Ferreira, R M; Torres-Júnior, J R S; Demétrio, C G B; Sá Filho, M F; Gimenes, L U; Penteado, L; D'Occhio, M J; Baruselli, P S

2014-09-01

The influence of body condition score (BCS), rump fat thickness (RFAT), and live weight (LW), and the changes in these parameters during the interval from 165 of prepartum (i.e., 125 days of prior gestation) to 112 postpartum on first service conception and pregnancy rates were investigated in suckled Zebu (Bos indicus) beef cows (n = 266) subjected to timed artificial insemination (TAI) followed by natural mating. The aforementioned parameters were recorded at 165 ± 14 days (mean ± standard error) prepartum (concurrent with the weaning of previous calf), at parturition, and at 42 ± 7 days (at the onset of the synchronization of ovulation protocol), 82 ± 7 days (30 days after TAI), and 112 ± 7 days (60 days after TAI) postpartum. At the start of the breeding season (BS), cows were subjected to a synchronization of ovulation program for TAI. Bulls were placed with cows 10 days after TAI and remained until the end of the study (112 days postpartum). Cows with the highest BCS at parturition had an increased probability of first service conception rate at 60 days after TAI (P = 0.02) and a reduced probability of occurrence of pregnancy loss (P = 0.05). Also, cows had a greater likelihood of conceiving postpartum if they had greater RFAT and BCS at 165 ± 14 days prepartum (P = 0.01 and P = 0.03, respectively) and at parturition (P = 0.0007 and P = 0.003, respectively). Cows that had an increase in RFAT and BCS during the dry period (i.e., interval from weaning of the previous calf to parturition) also had a greater likelihood of conceiving (P = 0.03 and P = 0.06, respectively) during the BS. Among the different time points, RFAT and BCS at parturition had the largest impact on risk of conception during the BS. The LW was a poor predictor of conception during the BS (P = 0.11-0.68) except for LW at 165 ± 14 days prepartum (P = 0.01). Collectively, the findings indicated that the likelihood of conception during the BS was highest in cows that had an improvement in RFAT and BCS during the dry period. Therefore, assuring a good nutritional status in the dry period (BCS ≥ 3.0 at 165 ± 14 days prepartum and ≥3.25 at parturition) is an important aim to optimize the postpartum conception rate of suckled Zebu beef cows subjected to TAI followed by natural mating. Copyright © 2014 Elsevier Inc. All rights reserved.

Effects of excess metabolizable protein on ovarian function and circulating amino acids of beef cows: 2. Excessive supply in varying concentrations from corn gluten meal.

PubMed

Geppert, T C; Meyer, A M; Perry, G A; Gunn, P J

2017-04-01

In the dairy industry, excess dietary CP is consistently correlated with decreased conception rates. However, amount of excess CP effects on reproductive function in beef cattle is largely undefined. The objective of this experiment was to determine the effects of excess metabolizable protein (MP) supplementation from a moderately abundant rumen undegradable protein (RUP) source (corn gluten meal: 62% RUP) on ovarian function and circulating amino acid (AA) concentrations in beef cows consuming low quality forage. Non-pregnant, non-lactating beef cows (n=16) were allocated by age, BW and body condition score (BCS) to 1 of 2 isocaloric supplements designed to maintain BW for 60 days. Cows had ad libitum access to corn stalks and were individually offered a corn gluten meal-based supplement daily at 125% (MP125) or 150% (MP150) of National Research Council (NRC) MP requirements. After a 20-day supplement adaptation period, cows were synchronized for ovulation. After 10 days of synchronization, follicular growth was reset with gonadotropin releasing hormone. Daily thereafter, transrectal ultrasonography was performed to diagram ovarian follicular waves, and blood samples were collected for hormone, metabolite and AA analyses. After 7 days of observation of estrus, corpus luteum (CL) size was determined via ultrasound. Data were analyzed using the MIXED procedures of SAS. No differences (P⩾0.21) in BW and BCS existed throughout the study; however, plasma urea N at ovulation was greater (P=0.04) in MP150. Preovulatory ovarian follicle size at dominance, duration of dominance, size at spontaneous luteolysis, length of proestrus and wavelength were not different (P⩾0.11) between treatments. However, ovulatory follicles were larger (P=0.04) and average antral follicle count was greater (P=0.01) in MP150 than MP125. Estradiol concentration and ratio of estradiol to ovulatory follicle volume were not different due to treatment (P⩾0.25). While CL volume 7 days post-estrus was greater (P<0.01) in MP150 than MP125, circulating progesterone 7 days post-estrus and ratio of progesterone to CL volume were not different (P⩾0.21). Total AA were not different (P⩾0.76) at study initiation or completion; however, as a percent of total AA, branched-chain AA at ovulation were greater (P=0.02) in MP150. In conclusion, supplementation of CP at 150% of NRC MP requirements from a moderately undegradable protein source may enhance growth of the ovulatory follicle and subsequent CL compared with MP supplementation at 125% of NRC MP requirements.

Verification of a Byzantine-Fault-Tolerant Self-stabilizing Protocol for Clock Synchronization

NASA Technical Reports Server (NTRS)

Malekpour, Mahyar R.

2008-01-01

This paper presents the mechanical verification of a simplified model of a rapid Byzantine-fault-tolerant self-stabilizing protocol for distributed clock synchronization systems. This protocol does not rely on any assumptions about the initial state of the system except for the presence of sufficient good nodes, thus making the weakest possible assumptions and producing the strongest results. This protocol tolerates bursts of transient failures, and deterministically converges within a time bound that is a linear function of the self-stabilization period. A simplified model of the protocol is verified using the Symbolic Model Verifier (SMV). The system under study consists of 4 nodes, where at most one of the nodes is assumed to be Byzantine faulty. The model checking effort is focused on verifying correctness of the simplified model of the protocol in the presence of a permanent Byzantine fault as well as confirmation of claims of determinism and linear convergence with respect to the self-stabilization period. Although model checking results of the simplified model of the protocol confirm the theoretical predictions, these results do not necessarily confirm that the protocol solves the general case of this problem. Modeling challenges of the protocol and the system are addressed. A number of abstractions are utilized in order to reduce the state space.

Clock Synchronization for Multihop Wireless Sensor Networks

ERIC Educational Resources Information Center

Solis Robles, Roberto

2009-01-01

In wireless sensor networks, more so generally than in other types of distributed systems, clock synchronization is crucial since by having this service available, several applications such as media access protocols, object tracking, or data fusion, would improve their performance. In this dissertation, we propose a set of algorithms to achieve…

The state-of-the-art of emergency contraception with the cutting edge drug.

PubMed

Sarkar, Narendra Nath

2011-01-01

The objective of this study is to evaluate and elucidated the potential of selective progesterone receptor modulators (SPRMs) to be an effective emergency contraception (EC). The data are extracted from the literature through the MEDLINE database service from 2000-2010. The SPRMs are in fact progesterone receptor ligands that could bind to progesterone receptor (PR) and exert antagonistic, agonistic or mixed agonist-antagonistic effects. These SPRMs are mifepristone, onapristone, asoprisnil, ulipristal, proellex among other compounds. Currently developed SPRMs may exert contraceptive effects by inhibiting ovulation and retarding endometrial synchronization. Low-doses of progesterone antagonists retard endometrial maturation without affecting ovulation. Mifepristone being a SPRM is effective for prevention of pregnancy but with prostaglandin acts as an excellent abortifacient; yet could not compete with levonorgestrel as EC. However, a single dose of 30 mg ulipristal acetate, another SPRM with similar effectiveness and side effect profiles as 1.5 mg levonorgestrel EC, has shown wider 'window of effect' by inhibition of the LH peak even if administered at the advanced pre-ovulatory phase, a time when use of levonorgestrel EC is no longer effective. Thus, ulipristal acetate goes one-step ahead of levonorgestrel in the field of emergency contraception treatment. Further studies are needed to explore the potential of other SPRMs to be cutting edge emergency contraceptive drugs.

Treatment with eCG decreases the vascular density and increases the glandular density of the bovine uterus.

PubMed

Mona e Pinto, J; Pavanelo, V; Alves de Fátima, L; Medeiros de Carvalho Sousa, L M; Pacheco Mendes, G; Machado Ferreira, R; Ayres, H; Sampaio Baruselli, P; Palma Rennó, F; de Carvallo Papa, P

2014-06-01

The uterus plays an essential role in mammalian reproduction and is a target of several hormonal protocols used to improve fertility in cattle. Many studies highlighted the importance of eCG treatment following fixed-time artificial insemination in improving follicular growth, ovulation and pregnancy rates in cattle. Moreover, eCG has been implicated in angiogenesis, leading to important changes in uterine blood flow and vascularisation. However, there is still a lack of information regarding the specific alterations induced by eCG upon glandular and vascular characteristics of bovine uterus. To investigate the influence of eCG on: uterine thickness and area; uterine artery diameter and area; uterine vascular and gland density; and the expression of the VEGFA-system, the uteri of crossbred beef cows were collected. All cows were submitted to follicular wave emergence synchronization. On day four of protocol, cows submitted to superovulation (n = 6) received 2000 IU eCG, on day eight, after expected follicular deviation, cows submitted to stimulatory treatment (n = 5) received 400 IU eCG. Control cows (n = 5) did not receive eCG. On day five po cows were subjected to ultrassonographic evaluation and slaughtered for uterine tissue sampling on day six po. Uterine vessels and glands were quantified by the counting point stereological method. The VEGFA-system was localized in different cellular types, showing no qualitative or quantitative differences in the site of expression or the intensity of the positive signal among the groups. Vascular density was decreased in the endometrium of stimulated and myometrium of superovulated cows compared with the control ones, which showed higher vascular density in the myometrium and endometrium of the ipsilateral uterine horn. The uterine gland density was higher in superovulated compared with stimulated and control cows. Thus, we can infer that stimulatory or superovulatory treatments with eCG influence the vascular density in the endometrium and myometrium in cattle. © 2014 Blackwell Verlag GmbH.

Cislan-2 extension final document by University of Twente (Netherlands)

NASA Astrophysics Data System (ADS)

Niemegeers, Ignas; Baumann, Frank; Beuwer, Wim; Jordense, Marcel; Pras, Aiko; Schutte, Leon; Tracey, Ian

1992-01-01

Results of worked performed under the so called Cislan extension contract are presented. The adaptation of the Cislan 2 prototype design to an environment of interconnected Local Area Networks (LAN's) instead of a single 802.5 token ring LAN is considered. In order to extend the network architecture, the Interconnection Function (IF) protocol layer was subdivided into two protocol layers: a new IF layer, and below the Medium Enhancement (ME) protocol layer. Some small enhancements to the distributed bandwidth allocation protocol were developed, which in fact are also applicable to the 'normal' Cislan 2 system. The new services and protocols are described together with some scenarios and requirements for the new internetting Cislan 2 system. How to overcome the degradation of the quality of speech due to packet loss on the LAN subsystem was studied. Experiments were planned in order to measure this speech quality degradation. Simulations were performed of two Cislan subsystems, the bandwidth allocation protocol and the clock synchronization mechanism. Results on both simulations, performed on SUN workstations using QNAP as a simulation tool, are given. Results of the simulations of the clock synchronization mechanism, and results of the simulation of the distributed bandwidth allocation protocol are given.

Minimal stimulation or clomiphene citrate as first-line therapy in women with polycystic ovary syndrome: a randomized controlled trial.

PubMed

Abu Hashim, Hatem; Bazeed, Mohamed; Abd Elaal, Ibrahim

2012-02-01

To compare the efficacy of minimal stimulation and clomiphene citrate (CC) as a first-line treatment for anovulatory infertility associated with polycystic ovary syndrome (PCOS). One hundred and thirteen women with PCOS were selected in this randomized controlled trial. Patients received minimal stimulation protocol consisted of 5 days CC (100 mg/day) then 150 IU of highly purified uFSH on cycle day 9 (n = 58, 159 cycles) or CC only (n = 55, 153 cycles) for up to three cycles. Outcome measures were: clinical pregnancy rate per cycle, number of growing and mature follicles, serum E2, endometrial thickness at the hCG day, serum P, ovulation and miscarriage rates. There were no differences between both groups regarding the clinical pregnancy rate per cycle and per woman (8.8% vs. 7.8 % and 24.1% vs. 21.8%; p = 0.23, p = 0.36, respectively). One twin pregnancy occurred in each group. Miscarriage rate was comparable (14.3% vs. 16.7%; p = 0.38). No differences were found regarding the number of follicles, serum P, ovulation rate, E2 and endometrial thickness at the hCG day (7.8 ± 0.5 vs. 7.6 ± 0.6 mm; p = 0.52). Ovulation induction with minimal stimulation is not more effective than CC alone for achieving pregnancy when used as initial treatment in PCOS patients.

An NTP Stratum-One Server Farm Fed By IEEE-1588

DTIC Science & Technology

2010-01-01

Serial Time Code Formats,” U.S. Army White Sands Missile Range, N.M. [11] J. Eidson , 2005, “IEEE-1588 Standard for a Precision Clock Synchronization ... synchronized to its Master Clocks via IRIG-B time code on a low- frequency RF distribution system. The availability of Precise Time Protocol (PTP, IEEE...forwarding back to the requestor. The farm NTP servers are synchronized to the USNO Master Clocks using IRIG-B time code. The current standard NTP

Return of ovulation and menses in postpartum nonlactating women: a systematic review.

PubMed

Jackson, Emily; Glasier, Anna

2011-03-01

To estimate, from the literature, when nonlactating postpartum women regain fertility. We searched PubMed and Cochrane Library databases for all articles (in all languages) published in peer-reviewed journals from database inception through May 2010 for evidence related to the return of ovulation and menses in nonlactating postpartum women. Search terms included "Fertility" (Mesh) OR "Ovulation" (Mesh) OR "Ovulation Detection" (Mesh) OR "Ovulation Prediction" (Mesh) OR fertility OR ovulat* AND "Postpartum Period" (Mesh) OR postpartum OR puerperium AND Human AND Female. We included articles assessing nonlactating women's first ovulation postpartum. Studies in which women breastfed for any period of time or in whom lactation was suppressed with medications were excluded. We identified 1,623 articles; six articles reported four studies met our inclusion criteria. In three studies utilizing urinary pregnanediol levels to measure ovulation, mean day of first ovulation ranged from 45 to 94 days postpartum; 20%-71% of first menses were preceded by ovulation and 0%-60% of these ovulations were potentially fertile. In one study that used basal body temperature to measure ovulation, mean first ovulation occurred on day 74 postpartum; 33% of first menses were preceded by ovulation and 70% of these were potentially fertile. Most nonlactating women will not ovulate until 6 weeks postpartum. A small number of women will ovulate earlier, potentially putting them at risk for pregnancy sooner, although the fertility of these early ovulations is not well-established. The potential risk of pregnancy soon after delivery underscores the importance of initiating postpartum contraception in a timely fashion.

Model Checking a Byzantine-Fault-Tolerant Self-Stabilizing Protocol for Distributed Clock Synchronization Systems

NASA Technical Reports Server (NTRS)

Malekpour, Mahyar R.

2007-01-01

This report presents the mechanical verification of a simplified model of a rapid Byzantine-fault-tolerant self-stabilizing protocol for distributed clock synchronization systems. This protocol does not rely on any assumptions about the initial state of the system. This protocol tolerates bursts of transient failures, and deterministically converges within a time bound that is a linear function of the self-stabilization period. A simplified model of the protocol is verified using the Symbolic Model Verifier (SMV) [SMV]. The system under study consists of 4 nodes, where at most one of the nodes is assumed to be Byzantine faulty. The model checking effort is focused on verifying correctness of the simplified model of the protocol in the presence of a permanent Byzantine fault as well as confirmation of claims of determinism and linear convergence with respect to the self-stabilization period. Although model checking results of the simplified model of the protocol confirm the theoretical predictions, these results do not necessarily confirm that the protocol solves the general case of this problem. Modeling challenges of the protocol and the system are addressed. A number of abstractions are utilized in order to reduce the state space. Also, additional innovative state space reduction techniques are introduced that can be used in future verification efforts applied to this and other protocols.

Effectiveness of intravaginal progesterone inserts and FSH for inducing synchronized estrus and increasing lambing rate in anestrous ewes.

PubMed

Knights, M; Hoehn, T; Lewis, P E; Inskeep, E K

2001-05-01

The objectives of this study were to determine whether a new progesterone (P4)-releasing intravaginal insert would induce fertile estrus and whether FSH combined with the insert would increase prolificacy in anestrous ewes introduced to rams. Ewes of mixed breeding on six farms were assigned to four randomized treatments: control (C), n = 73; 12 d P4 (polycapralactone [PCL] insert with 0.82 g P4), (P12), n = 73; 12 d P4 plus i.m. FSH (Folltropin, 55 mg NIH-FSH-P1 equivalent) in propylene glycol, 24 h before insert removal, (P12F), n = 71; and 5 d P4 plus FSH (P5F), n = 77. Growth and ovulation of follicles were observed ultrasonographically in 20 ewes at four farms (five/treatment) at insert removal and 36, 48, 72, and 96 h later. Intact rams (1:15 ewes in multiple-sire groups) were joined at insert removal, and raddle marks were observed every 12 h for 5 d. On d 26 to 30, rams were removed; ewes were examined for pregnancy then and 20 d later. Percentage of ewes marked by rams was greater in P4-treated (66 to 79%) than in C (12%; P < 0.01) ewes and in P5F (79%) than in P12F (66%; P < 0.05). Diameters of largest follicles at insert removal were greater (P < 0.05) in P4-treated (5.5 +/- 0.2) than in C ewes (4.8 +/- 0.2). Progesterone increased numbers of follicles > 3 mm (P < 0.01) or ovulated (P < 0.05; 2.6 +/- 0.6 vs 1.3 +/- 0.6 in C ewes) and FSH increased number of follicles > 3 mm (P < 0.05). In FSH-treated ewes, ovulation rate tended to be greater after treatment with P4 for 5 than for 12 d (P = 0.09, 3.3 +/- 0.6 and 2.2 +/- 0.4, respectively). More P4-treated than C ewes lambed (P < 0.01) to the first (38 to 45 vs 0%) or both (63 to 66 vs 41%) service periods. Prolificacy (first service) did not differ between FSH-treated ewes (P12F + P5F; 1.8 +/- 0.1) and ewes treated with P4 only (P12; 1.6 +/- 0.1). However, FSH increased prolificacy to first service (1.8 +/- 0.1) over prolificacy to second service (C ewes 1.5 +/- 0.1; P < 0.05, and all ewes 1.4 +/- 0.1; P < 0.01). Pregnancy retention did not differ among treatments but was greater (P < 0.01) in ewes that conceived at the first (90.9 +/- 3.7) than at the second (72.5 +/- 3.3) service period. In conclusion, a PCL insert in combination with ram introduction at insert removal was more effective than ram introduction alone to induce synchronized estrus and ovulation and to yield pregnancy after one or two service periods. Treatment with P4 for 5 d was as effective as for 12 d to induce fertile estrus in FSH-treated anestrous ewes.

78 FR 39691 - Closed Captioning of Internet Protocol-Delivered Video Programming: Implementation of the Twenty...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-02

... captioning synchronization requirements for covered apparatus, and on how DVD and Blu-ray players can fulfill... captioning capabilities of certain apparatus on which consumers view video programming. DATES: Comments are... synchronization requirements for covered apparatus, and on how DVD and Blu-ray players can fulfill the closed...

Ovulation home test

MedlinePlus

... test (home test); Ovulation prediction test; Ovulation predictor kit; Urinary LH immunoassays; At-home ovulation prediction test; ... Ovulation prediction test kits most often come with five to seven sticks. You may need to test for several days to detect a ...

Cessation of oscillations in a chemo-mechanical oscillator

NASA Astrophysics Data System (ADS)

Phogat, Richa; Tiwari, Ishant; Kumar, Pawan; Rivera, Marco; Parmananda, Punit

2018-06-01

In this paper, different methods for cessation of oscillations in a chemo-mechanical oscillator [mercury beating heart (MBH)] are presented. The first set of experiments were carried out on a single MBH oscillator. To achieve cessation of oscillations, two protocols, namely, inverted feedback and delayed feedback were employed. In the second set of experiments, two quasi-identical MBH oscillators are considered. They are first synchronized via a bidirectional attractive coupling. These two synchronized oscillators are thereafter coupled with a unidirectional repulsive coupling and the system dynamics were observed. Subsequently, in the next protocol, the effect of a unidirectional delay coupling on the two synchronized oscillators was explored. The cessation of oscillations in all the above experimental setups was observed as the feedback/coupling was switched on at a suitable strength. Oscillatory dynamics of the system were restored when the feedback/coupling was switched off.

Fault-Tolerant Self-Stabilizing Distributed Clock Synchronization Protocol for Arbitrary Digraphs

NASA Technical Reports Server (NTRS)

Malekpour, Mahyar R. (Inventor)

2014-01-01

A self-stabilizing network in the form of an arbitrary, non-partitioned digraph includes K nodes having a synchronizer executing a protocol. K-1 monitors of each node may receive a Sync message transmitted from a directly connected node. When the Sync message is received, the logical clock value for the receiving node is set to between 0 and a communication latency value (gamma) if the clock value is less than a minimum event-response delay (D). A new Sync message is also transmitted to any directly connected nodes if the clock value is greater than or equal to both D and a graph threshold (T(sub S)). When the Sync message is not received the synchronizer increments the clock value if the clock value is less than a resynchronization period (P), and resets the clock value and transmits a new Sync message to all directly connected nodes when the clock value equals or exceeds P.

Performance analysis of wireless sensor networks in geophysical sensing applications

NASA Astrophysics Data System (ADS)

Uligere Narasimhamurthy, Adithya

Performance is an important criteria to consider before switching from a wired network to a wireless sensing network. Performance is especially important in geophysical sensing where the quality of the sensing system is measured by the precision of the acquired signal. Can a wireless sensing network maintain the same reliability and quality metrics that a wired system provides? Our work focuses on evaluating the wireless GeoMote sensor motes that were developed by previous computer science graduate students at Mines. Specifically, we conducted a set of experiments, namely WalkAway and Linear Array experiments, to characterize the performance of the wireless motes. The motes were also equipped with the Sticking Heartbeat Aperture Resynchronization Protocol (SHARP), a time synchronization protocol developed by a previous computer science graduate student at Mines. This protocol should automatically synchronize the mote's internal clocks and reduce time synchronization errors. We also collected passive data to evaluate the response of GeoMotes to various frequency components associated with the seismic waves. With the data collected from these experiments, we evaluated the performance of the SHARP protocol and compared the performance of our GeoMote wireless system against the industry standard wired seismograph system (Geometric-Geode). Using arrival time analysis and seismic velocity calculations, we set out to answer the following question. Can our wireless sensing system (GeoMotes) perform similarly to a traditional wired system in a realistic scenario?

Construction and Operation of a High-Speed, High-Precision Eye Tracker for Tight Stimulus Synchronization and Real-Time Gaze Monitoring in Human and Animal Subjects.

PubMed

Farivar, Reza; Michaud-Landry, Danny

2016-01-01

Measurements of the fast and precise movements of the eye-critical to many vision, oculomotor, and animal behavior studies-can be made non-invasively by video oculography. The protocol here describes the construction and operation of a research-grade video oculography system with ~0.1° precision over the full typical viewing range at over 450 Hz with tight synchronization with stimulus onset. The protocol consists of three stages: (1) system assembly, (2) calibration for both cooperative, and for minimally cooperative subjects (e.g., animals or infants), and (3) gaze monitoring and recording.

On chaos synchronization and secure communication.

PubMed

Kinzel, W; Englert, A; Kanter, I

2010-01-28

Chaos synchronization, in particular isochronal synchronization of two chaotic trajectories to each other, may be used to build a means of secure communication over a public channel. In this paper, we give an overview of coupling schemes of Bernoulli units deduced from chaotic laser systems, different ways to transmit information by chaos synchronization and the advantage of bidirectional over unidirectional coupling with respect to secure communication. We present the protocol for using dynamical private commutative filters for tap-proof transmission of information that maps the task of a passive attacker to the class of non-deterministic polynomial time-complete problems. This journal is © 2010 The Royal Society

Kennedy Space Center Timing and Countdown Interface to Kennedy Ground Control Subsystem

NASA Technical Reports Server (NTRS)

Olsen, James C.

2015-01-01

Kennedy Ground Control System (KGCS) engineers at the National Aeronautics and Space Administration (NASA) Kennedy Space Center (KSC) are developing a time-tagging process to enable reconstruction of the events during a launch countdown. Such a process can be useful in the case of anomalies or other situations where it is necessary to know the exact time an event occurred. It is thus critical for the timing information to be accurate. KGCS will synchronize all items with Coordinated Universal Time (UTC) obtained from the Timing and Countdown (T&CD) organization. Network Time Protocol (NTP) is the protocol currently in place for synchronizing UTC. However, NTP has a peak error that is too high for today's standards. Precision Time Protocol (PTP) is a newer protocol with a much smaller peak error. The focus of this project has been to implement a PTP solution on the network to increase timing accuracy while introducing and configuring the implementation of a firewall between T&CD and the KGCS network.

Integrated Formal Analysis of Timed-Triggered Ethernet

NASA Technical Reports Server (NTRS)

Dutertre, Bruno; Shankar, Nstarajan; Owre, Sam

2012-01-01

We present new results related to the verification of the Timed-Triggered Ethernet (TTE) clock synchronization protocol. This work extends previous verification of TTE based on model checking. We identify a suboptimal design choice in a compression function used in clock synchronization, and propose an improvement. We compare the original design and the improved definition using the SAL model checker.

Incidence of double ovulation during the early postpartum period in lactating dairy cows.

PubMed

Kusaka, Hiromi; Miura, Hiroshi; Kikuchi, Motohiro; Sakaguchi, Minoru

2017-03-15

In lactating cattle, the incidence of twin calving has many negative impacts on production and reproduction in dairy farming. In almost all cases, natural twinning in dairy cattle is the result of double ovulation. It has been suggested that the milk production level of cows influences the number of ovulatory follicles. The objective of the present study was to investigate the incidence of double ovulations during the early postpartum period in relation to the productive and reproductive performance of dairy cows. The ovaries of 43 Holstein cows (26 primiparous and 17 multiparous) were ultrasonographically scanned throughout the three postpartum ovulation sequences. The incidence of double ovulation in the unilateral ovaries was 66.7%, with a higher incidence in the right ovary than in the left, whereas that in bilateral ovaries was 33.3%. When double ovulations were counted dividing into each side ovary in which ovulations occurred, the total frequency of ovulations deviated from a 1:1 ratio (60.3% in the right side and 39.7% in the left side, P < 0.05). In multiparous cows, double ovulation occurred more frequently than in primiparous cows (58.8% vs. 11.5% per cow and 30.0% vs. 3.8% per ovulation, respectively P < 0.01). The double ovulators experienced more anovulatory repeated waves of follicles before their first ovulations than the single ovulators, which resulted in an extension of the period from parturition to third ovulation (81.5 days vs. 64.2 days, P < 0.05). In the multiparous cows, the double ovulators exhibited higher peak milk yield (P < 0.01) with lower milk lactose concentration (P < 0.05), indicating the prevalence of a more severe negative energy balance during the postpartum 3-month compared to the multiparous single ovulators. Our results showed that, regardless of their parity, double ovulation had no impact on the reproductive performance of the cows. Two multiparous cows that experienced double ovulation during the early postpartum period subsequently conceived twin fetuses. It can be speculated that the incidence of double ovulations during the early postpartum period partly contributes to the increased incidence of undesirable twin births in multiparous dairy cows. Copyright © 2016. Published by Elsevier Inc.

Model Checking A Self-Stabilizing Synchronization Protocol for Arbitrary Digraphs

NASA Technical Reports Server (NTRS)

Malekpour, Mahyar R.

2012-01-01

This report presents the mechanical verification of a self-stabilizing distributed clock synchronization protocol for arbitrary digraphs in the absence of faults. This protocol does not rely on assumptions about the initial state of the system, other than the presence of at least one node, and no central clock or a centrally generated signal, pulse, or message is used. The system under study is an arbitrary, non-partitioned digraph ranging from fully connected to 1-connected networks of nodes while allowing for differences in the network elements. Nodes are anonymous, i.e., they do not have unique identities. There is no theoretical limit on the maximum number of participating nodes. The only constraint on the behavior of the node is that the interactions with other nodes are restricted to defined links and interfaces. This protocol deterministically converges within a time bound that is a linear function of the self-stabilization period. A bounded model of the protocol is verified using the Symbolic Model Verifier (SMV) for a subset of digraphs. Modeling challenges of the protocol and the system are addressed. The model checking effort is focused on verifying correctness of the bounded model of the protocol as well as confirmation of claims of determinism and linear convergence with respect to the self-stabilization period.

Pronuclear synchronization and nuclear morphology of mature and in vitro matured oocytes in the rat: an ultrastructural study.

PubMed

Cincik, M; Baykal, B; Zeteroglu, S; Onalan, G; Ceyhan, S T; Ergur, R

2005-01-01

The objective of this study was to evaluate synchronous and asynchronous pronucleus (PN) formation and the related patterns of juxtapositional nucleolus (n) formation in immature (prophase I [PI] and metaphase I [MI]) and mature (metaphase II [MII]) oocytes after fertilization, both ultrastructurally and at the level of light microscope. A single dose of 15 IU gonadotrophin was injected subcutaneously to twenty four 26-wk-old, female Wistar rats to induce ovulation. Human chorionic gonadotrophin (4 IU) was administered 40 h later, and after 4-6 h the ovaries were dissected, and the oocytes were aspirated. A total of 214 rat oocytes were classified according to a maturation index as follows: group I, 80 PI oocytes; group II, 50 MI oocytes; and group III, 84 MII oocytes. Immature oocytes were in vitro matured for 18-36 h. Spermatozoa were acquired by microepididymal sperm aspiration and processed using swim-up technique. Intracytoplasmic sperm injection was performed on mature oocytes after 2 h of incubation and on in vitro matured (IVM) oocytes 4 h after maturation. Pronuclear synchronization [both pronucleases (PNs) centrally located, equal sized, with equal numbers and sizes of juxtapositional nucleoli (Nn)] was observed in fertilized oocytes. Asynchronous PN formation (diversity between male and female PNs, related to dimensions, localization, and the number of Nn) in groups I, II, and III was found in 75, 86, and 47% of preembryos, respectively. There was a significant difference of synchronous pronuclear formation between mature and IVM oocytes (P < 0.05). In IVM oocytes, asynchronous PN formation is high, and juxtapositional pronucleolar patterns are observed to be low by transmission electron microscope (TEM).

Observations on the ovulating process of the red flagellated shrimp Acetes chinensis

NASA Astrophysics Data System (ADS)

Chen, Qiu

1986-12-01

Acetes chinensis always ovulate in the dark at night. Two to five hours before ovulation, the mature oocytes change from white to orange. In the meantime, meiosis of the oocytes occurs, and reaches the metaphase just prior to ovulation. If ovarian colour change starts in the dark at night but ovulation does not start by break of dawn, ovulation will be inhibited and meiosis of the cells will be blocked.

Finite-Time and Fixed-Time Cluster Synchronization With or Without Pinning Control.

PubMed

Liu, Xiwei; Chen, Tianping

2018-01-01

In this paper, the finite-time and fixed-time cluster synchronization problem for complex networks with or without pinning control are discussed. Finite-time (or fixed-time) synchronization has been a hot topic in recent years, which means that the network can achieve synchronization in finite-time, and the settling time depends on the initial values for finite-time synchronization (or the settling time is bounded by a constant for any initial values for fixed-time synchronization). To realize the finite-time and fixed-time cluster synchronization, some simple distributed protocols with or without pinning control are designed and the effectiveness is rigorously proved. Several sufficient criteria are also obtained to clarify the effects of coupling terms for finite-time and fixed-time cluster synchronization. Especially, when the cluster number is one, the cluster synchronization becomes the complete synchronization problem; when the network has only one node, the coupling term between nodes will disappear, and the synchronization problem becomes the simplest master-slave case, which also includes the stability problem for nonlinear systems like neural networks. All these cases are also discussed. Finally, numerical simulations are presented to demonstrate the correctness of obtained theoretical results.

Review: Using artificial insemination v. natural service in beef herds.

PubMed

Baruselli, P S; Ferreira, R M; Sá Filho, M F; Bó, G A

2018-03-20

The aim of this review is to compare the performance of different reproductive programs using natural service, estrus synchronization treatment before natural service (timed natural breeding (TNB)), artificial insemination (AI) following estrus detection and timed artificial insemination (TAI) in beef herds. It is well known that after parturition the beef cow undergoes a period of anestrous, when they do not exhibit estrus, eliminating the opportunity to become pregnant in the early postpartum by natural mating or by AI after detection of estrus. Hormonal stimulation is already a consistent and well-proven strategy used to overcome postpartum anestrus in beef herds. Basically, hormones that normally are produced during the estrous cycle of the cow can be administered in physiological doses to induce cyclicity and to precisely synchronize follicular growth, estrus and ovulation. Furthermore, two options of mating may be used after hormonal stimulation: natural service (i.e. utilization of bull service after synchronization, referred to as TNB) and TAI. These strategies improve the reproductive efficiency of the herds compared with natural service without estrus induction or synchronization. After the first synchronized service, the most common strategy adopted to get non-pregnant cows pregnant soon is the introduction of clean-up bulls until the end of the breeding season. However, methods to resynchronize non-pregnant cows after the first service are already well established and offer a potential tool to reduce the time for subsequent inseminations. Thus, the use of these technologies enable to eliminate the use of bulls by using resynchronization programs (i.e. two, three or four sequential TAI procedures). The dissemination of efficient reproductive procedures, such as TNB, TAI and Resynch programs, either isolated or in combination, enables the production of a greater quantity (obtaining increased pregnancy rates early in the breeding season) and quality (maximization of the use of AI with superior genetic sires) of beef calves. These technologies can contribute to improve the production efficiency, and consequently, improve livestock profitability.

Communication requested: Boar semen transport through the uterus and possible consequences for insemination.

PubMed

Rath, D; Knorr, C; Taylor, U

2016-01-01

Recent insemination techniques bypass the interactions between sperm and the uterine wall because the semen is deposited deep into the tip of uterine horn or directly into the oviduct. Such techniques allow high dilution of the ejaculates. After normal mating, semen entering the uterus communicates with the uterine milieu. Intact sperm of high mitochondrial membrane potential bind to uterine epithelial cells, whereas most of the unbound sperm in the uterine lumen have damaged membranes. Lectins are the most likely factors to mediate these sperm-uterine interactions. The lectin wheat germ agglutinin is known to induce the strongest binding of sperm, whereas binding is impaired when sialic acid receptors are blocked by wheat germ agglutinin. This suggests that sialic acid is involved in porcine sperm-endometrium interactions, and it is hypothesized that the use of a semen extender supplemented with sialidase would allow insemination with reduced sperm numbers. A lack of contact of sperm and seminal plasma with the uterine wall, as a result of deep insemination, may adversely affect (1) events during ovulation, (2) induction of immunologic tolerance against paternal antigens, (3) preparation of the endometrium for implantation and placentation, and (4) immunologic support required for the fetus during pregnancy. Seminal plasma is known to signal post-insemination changes in the uterine endometrium involving the redistribution of leukocytes. This may involve migration of leukocytes from the uterine wall to the ovary, as seminal plasma particularly increases the appearance of the major histocompatibility complex class II-positive cells. Uterine epithelial cells respond to sperm binding by the production of pro- or anti-inflammatory cytokines. These cytokines may include synchronizing substances, transferred through a counter-current pathway to the ipsilateral ovary, thereby accelerating the final maturation of preovulatory follicles and advancing time of ovulation. In several species, an ovulation-inducing factor exists in seminal plasma, first identified as ß-nerve growth factor in camelid semen, indicating another pathway that influences the hypothalamic-pituitary-gonadal axis. In summary, low-dose inseminations may not necessarily require semen deposition deep into the uterine horn, as binding inhibitors can circumvent the binding of sperm to the uterine wall. However, subsequent immune-relevant events that control ovulation and prepare the uterine milieu for the developing embryo should be taken into account. Copyright © 2016 Elsevier Inc. All rights reserved.

[Management by assisted reproductive technology in women with endometriosis: CNGOF-HAS Endometriosis Guidelines].

PubMed

Chauffour, C; Pouly, J-L; Gremeau, A-S

2018-03-01

Should the presence of endometriosis change the management of assisted reproductive technology? There is no difference in pregnancy rate after IVF between an agonist or antagonist protocol in patients with endometriosis, so the choice between one or the other of these protocols is free. But the review of the literature has shown an improvement in the chances of pregnancy in case of prolonged ovulation suppression before stimulation for IVF with a GnRH agonist analogue or with oral contraception, especially in cases of severe endometriosis. Endometriosis, regardless of the stage and type of lesions, would have no effect on the IVF results in terms of pregnancy rate and live birth rate, but with a lower number of oocytes collected, especially in cases of severe endometriosis. In a context of superficial endometriosis without pain and of infertility, surgical treatment of superficial endometriosis is not recommended just to increase the chances of pregnancy in IVF. Surgery may have a place in case of failure of IVF to improve the results of the ART. In case of recurrence of endometriosis, surgery is not better than IVF, a medico-surgical concertation is recommended. In addition, studies on ovulation stimulation for IVF do not show any aggravation of the symptoms associated with endometriosis lesions, or an acceleration of its progression, or an increase in the rate of recurrence of the disease. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Ovule development: identification of stage-specific and tissue-specific cDNAs.

PubMed Central

Nadeau, J A; Zhang, X S; Li, J; O'Neill, S D

1996-01-01

A differential screening approach was used to identify seven ovule-specific cDNAs representing genes that are expressed in a stage-specific manner during ovule development. The Phalaenopsis orchid takes 80 days to complete the sequence of ovule developmental events, making it a good system to isolate stage-specific ovule genes. We constructed cDNA libraries from orchid ovule tissue during archesporial cell differentiation, megasporocyte formation, and the transition to meiosis, as well as during the final mitotic divisions of female gametophyte development. RNA gel blot hybridization analysis revealed that four clones were stage specific and expressed solely in ovule tissue, whereas one clone was specific to pollen tubes. Two other clones were not ovule specific. Sequence analysis and in situ hybridization revealed the identities and domain of expression of several of the cDNAs. O39 encodes a putative homeobox transcription factor that is expressed early in the differentiation of the ovule primordium; O40 encodes a cytochrome P450 monooxygenase (CYP78A2) that is pollen tube specific. O108 encodes a protein of unknown function that is expressed exclusively in the outer layer of the outer integument and in the female gametophyte of mature ovules. O126 encodes a glycine-rich protein that is expressed in mature ovules, and O141 encodes a cysteine proteinase that is expressed in the outer integument of ovules during seed formation. Sequences homologous to these ovule clones can now be isolated from other organisms, and this should facilitate their functional characterization. PMID:8742709

Improvement of bovine in vitro embryo production by ovarian follicular wave synchronization prior to ovum pick-up.

PubMed

Cavalieri, F L B; Morotti, F; Seneda, M M; Colombo, A H B; Andreazzi, M A; Emanuelli, I P; Rigolon, L P

2018-09-01

This study evaluated the effects of the synchronization of ovarian follicular wave emergence on the efficiency of in vitro embryo production. Bos indicus cows (n = 20) were divided into two groups (control vs. synchronization) and subjected to repeated ovum pick-up (OPU) sessions (8 replicates each, with an interval of 21 days in a 2 × 2 crossover design) and subsequent in vitro embryo production. Cows in the control group (n = 10) were submitted to OPU procedures without any stimulation every 21 days. Animals in the synchronization group received a protocol-based progesterone implant, estradiol benzoate and prostaglandin on a random day of the estrus cycle (Day 0) and the OPU was performed on Day 5. After in vitro production, embryos were transferred to recipients synchronized at a fixed time and the diagnosis was performed 60 days later. An evaluation of the parameters for each OPU session revealed that donors that received the synchronization protocol pre-OPU showed a greater number of embryos (5.9 ± 0.5 vs. 4.5 ± 0.4; P = 0.037), higher rate of embryo production (45.8% vs. 38.5%; P = 0.001) and higher mean number of conceptions per group (2.2 ± 0.2 vs. 1.6 ± 0.2; P = 0.07) in relation to the group that did not receive hormonal treatment. We concluded that synchronization of the follicular wave prior to OPU showed positive effects on in vitro embryo production as well as on pregnancy rates. Copyright © 2017 Elsevier Inc. All rights reserved.

Synchronization of Somatic Embryogenesis in Date Palm Suspension Culture Using Abscisic Acid.

PubMed

Alwael, Hussain A; Naik, Poornananda M; Al-Khayri, Jameel M

2017-01-01

Somatic embryogenesis is considered the most effective method for commercial propagation of date palm. However, the limitation of obtaining synchronized development of somatic embryos remains an impediment. The synchronization of somatic embryo development is ideal for the applications to produce artificial seeds. Abscisic acid (ABA) is associated with stress response and influences in vitro growth and development. This chapter describes an effective method to achieve synchronized development of somatic embryos in date palm cell suspension culture. Among the ABA concentrations tested (0, 1, 10, 50, 100 μM), the best synchronized growth was obtained in response to 50-100 μM. Here we provide a comprehensive protocol for in vitro plant regeneration of date palm starting with shoot-tip explant, callus initiation and growth, cell suspension establishment, embryogenesis synchronization with ABA treatment, somatic embryo germination, and rooting as well as acclimatized plantlet establishment.

Versatile synchronized real-time MEG hardware controller for large-scale fast data acquisition.

PubMed

Sun, Limin; Han, Menglai; Pratt, Kevin; Paulson, Douglas; Dinh, Christoph; Esch, Lorenz; Okada, Yoshio; Hämäläinen, Matti

2017-05-01

Versatile controllers for accurate, fast, and real-time synchronized acquisition of large-scale data are useful in many areas of science, engineering, and technology. Here, we describe the development of a controller software based on a technique called queued state machine for controlling the data acquisition (DAQ) hardware, continuously acquiring a large amount of data synchronized across a large number of channels (>400) at a fast rate (up to 20 kHz/channel) in real time, and interfacing with applications for real-time data analysis and display of electrophysiological data. This DAQ controller was developed specifically for a 384-channel pediatric whole-head magnetoencephalography (MEG) system, but its architecture is useful for wide applications. This controller running in a LabVIEW environment interfaces with microprocessors in the MEG sensor electronics to control their real-time operation. It also interfaces with a real-time MEG analysis software via transmission control protocol/internet protocol, to control the synchronous acquisition and transfer of the data in real time from >400 channels to acquisition and analysis workstations. The successful implementation of this controller for an MEG system with a large number of channels demonstrates the feasibility of employing the present architecture in several other applications.

Versatile synchronized real-time MEG hardware controller for large-scale fast data acquisition

NASA Astrophysics Data System (ADS)

Sun, Limin; Han, Menglai; Pratt, Kevin; Paulson, Douglas; Dinh, Christoph; Esch, Lorenz; Okada, Yoshio; Hämäläinen, Matti

2017-05-01

Versatile controllers for accurate, fast, and real-time synchronized acquisition of large-scale data are useful in many areas of science, engineering, and technology. Here, we describe the development of a controller software based on a technique called queued state machine for controlling the data acquisition (DAQ) hardware, continuously acquiring a large amount of data synchronized across a large number of channels (>400) at a fast rate (up to 20 kHz/channel) in real time, and interfacing with applications for real-time data analysis and display of electrophysiological data. This DAQ controller was developed specifically for a 384-channel pediatric whole-head magnetoencephalography (MEG) system, but its architecture is useful for wide applications. This controller running in a LabVIEW environment interfaces with microprocessors in the MEG sensor electronics to control their real-time operation. It also interfaces with a real-time MEG analysis software via transmission control protocol/internet protocol, to control the synchronous acquisition and transfer of the data in real time from >400 channels to acquisition and analysis workstations. The successful implementation of this controller for an MEG system with a large number of channels demonstrates the feasibility of employing the present architecture in several other applications.

A role for parasites in stabilising the fig-pollinator mutualism.

PubMed

Dunn, Derek W; Segar, Simon T; Ridley, Jo; Chan, Ruth; Crozier, Ross H; Yu, Douglas W; Cook, James M

2008-03-11

Mutualisms are interspecific interactions in which both players benefit. Explaining their maintenance is problematic, because cheaters should outcompete cooperative conspecifics, leading to mutualism instability. Monoecious figs (Ficus) are pollinated by host-specific wasps (Agaonidae), whose larvae gall ovules in their "fruits" (syconia). Female pollinating wasps oviposit directly into Ficus ovules from inside the receptive syconium. Across Ficus species, there is a widely documented segregation of pollinator galls in inner ovules and seeds in outer ovules. This pattern suggests that wasps avoid, or are prevented from ovipositing into, outer ovules, and this results in mutualism stability. However, the mechanisms preventing wasps from exploiting outer ovules remain unknown. We report that in Ficus rubiginosa, offspring in outer ovules are vulnerable to attack by parasitic wasps that oviposit from outside the syconium. Parasitism risk decreases towards the centre of the syconium, where inner ovules provide enemy-free space for pollinator offspring. We suggest that the resulting gradient in offspring viability is likely to contribute to selection on pollinators to avoid outer ovules, and by forcing wasps to focus on a subset of ovules, reduces their galling rates. This previously unidentified mechanism may therefore contribute to mutualism persistence independent of additional factors that invoke plant defences against pollinator oviposition, or physiological constraints on pollinators that prevent oviposition in all available ovules.

A Role for Parasites in Stabilising the Fig-Pollinator Mutualism

PubMed Central

Dunn, Derek W; Segar, Simon T; Ridley, Jo; Chan, Ruth; Crozier, Ross H; Yu, Douglas W; Cook, James M

2008-01-01

Mutualisms are interspecific interactions in which both players benefit. Explaining their maintenance is problematic, because cheaters should outcompete cooperative conspecifics, leading to mutualism instability. Monoecious figs (Ficus) are pollinated by host-specific wasps (Agaonidae), whose larvae gall ovules in their “fruits” (syconia). Female pollinating wasps oviposit directly into Ficus ovules from inside the receptive syconium. Across Ficus species, there is a widely documented segregation of pollinator galls in inner ovules and seeds in outer ovules. This pattern suggests that wasps avoid, or are prevented from ovipositing into, outer ovules, and this results in mutualism stability. However, the mechanisms preventing wasps from exploiting outer ovules remain unknown. We report that in Ficus rubiginosa, offspring in outer ovules are vulnerable to attack by parasitic wasps that oviposit from outside the syconium. Parasitism risk decreases towards the centre of the syconium, where inner ovules provide enemy-free space for pollinator offspring. We suggest that the resulting gradient in offspring viability is likely to contribute to selection on pollinators to avoid outer ovules, and by forcing wasps to focus on a subset of ovules, reduces their galling rates. This previously unidentified mechanism may therefore contribute to mutualism persistence independent of additional factors that invoke plant defences against pollinator oviposition, or physiological constraints on pollinators that prevent oviposition in all available ovules. PMID:18336072

Gene Expression Profiles in Rice Developing Ovules Provided Evidence for the Role of Sporophytic Tissue in Female Gametophyte Development.

PubMed

Wu, Ya; Yang, Liyu; Cao, Aqin; Wang, Jianbo

2015-01-01

The development of ovule in rice (Oryza sativa) is vital during its life cycle. To gain more understanding of the molecular events associated with the ovule development, we used RNA sequencing approach to perform transcriptome-profiling analysis of the leaf and ovules at four developmental stages. In total, 25,401, 23,343, 23,647 and 23,806 genes were identified from the four developmental stages of the ovule, respectively. We identified a number of differently expressed genes (DEGs) from three adjacent stage comparisons, which may play crucial roles in ovule development. The DEGs were then conducted functional annotations and Kyoto encyclopedia of genes and genomes (KEGG) pathway analyses. Genes related to cellular component biogenesis, membrane-bounded organelles and reproductive regulation were identified to be highly expressed during the ovule development. Different expression levels of auxin-related and cytokinin-related genes were also identified at various stages, providing evidence for the role of sporophytic ovule tissue in female gametophyte development from the aspect of gene expression. Generally, an overall transcriptome analysis for rice ovule development has been conducted. These results increased our knowledge of the complex molecular and cellular events that occur during the development of rice ovule and provided foundation for further studies on rice ovule development.

Performance bounds on parallel self-initiating discrete-event

NASA Technical Reports Server (NTRS)

Nicol, David M.

1990-01-01

The use is considered of massively parallel architectures to execute discrete-event simulations of what is termed self-initiating models. A logical process in a self-initiating model schedules its own state re-evaluation times, independently of any other logical process, and sends its new state to other logical processes following the re-evaluation. The interest is in the effects of that communication on synchronization. The performance is considered of various synchronization protocols by deriving upper and lower bounds on optimal performance, upper bounds on Time Warp's performance, and lower bounds on the performance of a new conservative protocol. The analysis of Time Warp includes the overhead costs of state-saving and rollback. The analysis points out sufficient conditions for the conservative protocol to outperform Time Warp. The analysis also quantifies the sensitivity of performance to message fan-out, lookahead ability, and the probability distributions underlying the simulation.

Conservative parallel simulation of priority class queueing networks

NASA Technical Reports Server (NTRS)

Nicol, David

1992-01-01

A conservative synchronization protocol is described for the parallel simulation of queueing networks having C job priority classes, where a job's class is fixed. This problem has long vexed designers of conservative synchronization protocols because of its seemingly poor ability to compute lookahead: the time of the next departure. For, a job in service having low priority can be preempted at any time by an arrival having higher priority and an arbitrarily small service time. The solution is to skew the event generation activity so that the events for higher priority jobs are generated farther ahead in simulated time than lower priority jobs. Thus, when a lower priority job enters service for the first time, all the higher priority jobs that may preempt it are already known and the job's departure time can be exactly predicted. Finally, the protocol was analyzed and it was demonstrated that good performance can be expected on the simulation of large queueing networks.

Conservative parallel simulation of priority class queueing networks

NASA Technical Reports Server (NTRS)

Nicol, David M.

1990-01-01

A conservative synchronization protocol is described for the parallel simulation of queueing networks having C job priority classes, where a job's class is fixed. This problem has long vexed designers of conservative synchronization protocols because of its seemingly poor ability to compute lookahead: the time of the next departure. For, a job in service having low priority can be preempted at any time by an arrival having higher priority and an arbitrarily small service time. The solution is to skew the event generation activity so that the events for higher priority jobs are generated farther ahead in simulated time than lower priority jobs. Thus, when a lower priority job enters service for the first time, all the higher priority jobs that may preempt it are already known and the job's departure time can be exactly predicted. Finally, the protocol was analyzed and it was demonstrated that good performance can be expected on the simulation of large queueing networks.

Size of Ovulatory Follicles in Cattle Expressing Multiple Ovulations Naturally and Its Influence on Corpus Luteum Development and Fertility

USDA-ARS?s Scientific Manuscript database

Long-term genetic selection of cattle for fraternal twins has increased the frequency of twin and triplet ovulations. Although twin and triplet ovulations increased pregnancy rates initially, ratio of fetal number:ovulation site in pregnant females with twin (0.83) or triplet (0.73) ovulations was <...

Plasma progesterone profiles, ovulation rate, donor embryo yield and recipient embryo survival in native Saloia sheep in the fall and spring breeding seasons.

PubMed

Chagas e Silva, J; Lopes da Costa, L; Cidadão, R; Robalo Silva, J

2003-08-01

The response to superovulatory (SOV) and estrus synchronization (ES) treatments and the fertility of donor (n=68) and recipient (n=118) Saloia ewes was evaluated in the fall and spring breeding seasons. The proportion of acyclic ewes at treatment time was significantly higher in the spring than in the fall (42.6% versus 4.0%, P<0.00001). Donors treated with eCG had a significantly higher mean number of follicles over 5mm in diameter in the ovaries at embryo recovery and a significantly lower mean efficiency of recovery than FSH-treated ewes. These negative effects were more pronounced in the fall than in the spring, which resulted in a significantly lower mean number of total and fertilized ova recovered from eCG-treated ewes, compared to FSH donors in the fall, but not in the spring. Season had no significant effect on the ovulation rate and plasma P4 concentrations of recipients treated with a progestagen plus eCG combination. Although the recipient lambing and embryo survival rates were higher in the fall than in the spring the differences were not significant. No significant differences were observed in the ovulation rate or P4 concentrations of recipients that lambed compared to those that did not lamb. These preliminary results show that, in Portugal, response of Saloia ewes to SOV or ES treatments and donor fertility following the SOV treatment were similar in the spring and the fall, which suggests that in the spring acyclic ewes are in moderate anestrus. The effect of season on fertility following embryo transfer should be confirmed in further studies involving a larger number of animals. The semilaparoscopic transfer method reported here allowed lambing and embryo survival rates higher (although not significantly) than a standard surgical approach.

Use of two doses of cloprostenol in different intervals for estrus synchronization in hair sheep under tropical conditions.

PubMed

de Carvalho Menezes de Almeida, Sheylla Foligno; Souza-Fabjan, Joanna Maria Gonçalves; Balaro, Mario Felipe Alvarez; Bragança, Gláucia Mota; Pinto, Pedro Henrique Nicolau; de Almeida, José Gabriel; Moura, Ana Beatriz Bossois; da Fonseca, Jeferson Ferreira; Brandão, Felipe Zandonadi

2018-02-01

This study evaluated the effect of two doses of prostaglandin at different intervals on reproductive parameters of crossbred ewes. In Experiment 1, 30 ewes received two doses of 120 μg cloprostenol at 7 (G 7 days ), 9 (G 9 days ), or 11.5 (G 11.5 days ) days apart. Ultrasound assessments were performed from the first and second cloprostenol administration for 5 days or ovulation detection. Estrus signs were checked by a teaser male. Plasma progesterone concentration was measured before each cloprostenol dose. In Experiment 2, 95 ewes were allocated into the same treatments and after the second dose, ewes in estrus were mated. At 30 days after breeding, pregnancy diagnosis was conducted and prolificacy was evaluated at lambing. In Experiment 1, at the first cloprostenol administration, 50% of ewes had an active CL and all showed estrus. At the second administration, 66.7% of ewes had an active CL and one did not present estrus. There was no difference (P > 0.05) after the second dose for as follows: overall estrous response (90%), interval from cloprostenol administration to estrous onset (42.0 ± 4.9 h), estrus duration (31.5 ± 2.1 h), ovulation rate (100.0%), and number of ovulations (1.5 ± 0.3). In Experiment 2, both pregnancy and prolificacy rates were similar (P > 0.05) for G 7 days (73.3; 145%), G 9 days (75.9; 125%), or G 11.5 days (75.9; 145%), leading to an overall pregnancy rate of 75.0% (66/88) and prolificacy rate of 137% . Therefore, the three treatments proposed were able to promote high pregnancy and prolificacy rates in crossbred ewes.

Using synchronous software in Web-based nursing courses.

PubMed

Little, Barbara Battin; Passmore, Denise; Schullo, Shauna

2006-01-01

To promote learning and enhance immediacy and satisfaction, a college of nursing at a large research I southern university undertook a pilot project to incorporate synchronous classroom software into an ongoing online program. Two synchronous class sessions using voice over Internet protocol were offered in the Community/Public Health Nursing course through Elluminate Live! Upon conclusion of the lecture, students were divided into breakout groups to work on group projects. Surveys were administered to the students and faculty before and after the class sessions. Evaluation of the pedagogical strategies used in the synchronous sessions was conducted by instructional technology faculty. Students in the pilot group reported higher levels of satisfaction with the Web-based course with synchronous sessions. In addition, students reported that group time at the end of the session was helpful for completing group projects. A majority responded that synchronous session activities and assignments facilitated their understanding of course content. This article presents a description of the synchronous classroom pilot project along with recommendations for implementation and pedagogical approaches.

Angiosperm ovules: diversity, development, evolution

PubMed Central

Endress, Peter K.

2011-01-01

Background Ovules as developmental precursors of seeds are organs of central importance in angiosperm flowers and can be traced back in evolution to the earliest seed plants. Angiosperm ovules are diverse in their position in the ovary, nucellus thickness, number and thickness of integuments, degree and direction of curvature, and histological differentiations. There is a large body of literature on this diversity, and various views on its evolution have been proposed over the course of time. Most recently evo–devo studies have been concentrated on molecular developmental genetics in ovules of model plants. Scope The present review provides a synthetic treatment of several aspects of the sporophytic part of ovule diversity, development and evolution, based on extensive research on the vast original literature and on experience from my own comparative studies in a broad range of angiosperm clades. Conclusions In angiosperms the presence of an outer integument appears to be instrumental for ovule curvature, as indicated from studies on ovule diversity through the major clades of angiosperms, molecular developmental genetics in model species, abnormal ovules in a broad range of angiosperms, and comparison with gymnosperms with curved ovules. Lobation of integuments is not an atavism indicating evolution from telomes, but simply a morphogenetic constraint from the necessity of closure of the micropyle. Ovule shape is partly dependent on locule architecture, which is especially indicated by the occurrence of orthotropous ovules. Some ovule features are even more conservative than earlier assumed and thus of special interest in angiosperm macrosystematics. PMID:21606056

Bouncing Ball with a Uniformly Varying Velocity in a Metronome Synchronization Task.

PubMed

Huang, Yingyu; Gu, Li; Yang, Junkai; Wu, Xiang

2017-09-21

Sensorimotor synchronization (SMS), a fundamental human ability to coordinate movements with external rhythms, has long been thought to be modality specific. In the canonical metronome synchronization task that requires tapping a finger along with an isochronous sequence, a well-established finding is that synchronization is much more stable to an auditory sequence consisting of auditory tones than to a visual sequence consisting of visual flashes. However, recent studies have shown that periodically moving visual stimuli can substantially improve synchronization compared with visual flashes. In particular, synchronization of a visual bouncing ball that has a uniformly varying velocity was found to be not less stable than synchronization of auditory tones. Here, the current protocol describes the application of the bouncing ball with a uniformly varying velocity in a metronome synchronization task. The usage of the bouncing ball in sequences with different inter-onset intervals (IOI) is included. The representative results illustrate synchronization performance of the bouncing ball, as compared with the performances of auditory tones and visual flashes. Given its comparable synchronization performance to that of auditory tones, the bouncing ball is of particular importance for addressing the current research topic of whether modality-specific mechanisms underlay SMS.

Microprocessor-based integration of microfluidic control for the implementation of automated sensor monitoring and multithreaded optimization algorithms.

PubMed

Ezra, Elishai; Maor, Idan; Bavli, Danny; Shalom, Itai; Levy, Gahl; Prill, Sebastian; Jaeger, Magnus S; Nahmias, Yaakov

2015-08-01

Microfluidic applications range from combinatorial synthesis to high throughput screening, with platforms integrating analog perfusion components, digitally controlled micro-valves and a range of sensors that demand a variety of communication protocols. Currently, discrete control units are used to regulate and monitor each component, resulting in scattered control interfaces that limit data integration and synchronization. Here, we present a microprocessor-based control unit, utilizing the MS Gadgeteer open framework that integrates all aspects of microfluidics through a high-current electronic circuit that supports and synchronizes digital and analog signals for perfusion components, pressure elements, and arbitrary sensor communication protocols using a plug-and-play interface. The control unit supports an integrated touch screen and TCP/IP interface that provides local and remote control of flow and data acquisition. To establish the ability of our control unit to integrate and synchronize complex microfluidic circuits we developed an equi-pressure combinatorial mixer. We demonstrate the generation of complex perfusion sequences, allowing the automated sampling, washing, and calibrating of an electrochemical lactate sensor continuously monitoring hepatocyte viability following exposure to the pesticide rotenone. Importantly, integration of an optical sensor allowed us to implement automated optimization protocols that require different computational challenges including: prioritized data structures in a genetic algorithm, distributed computational efforts in multiple-hill climbing searches and real-time realization of probabilistic models in simulated annealing. Our system offers a comprehensive solution for establishing optimization protocols and perfusion sequences in complex microfluidic circuits.

In vivo and in vitro study of the function of the left and right bovine ovaries.

PubMed

Karamishabankareh, Hamed; Hajarian, Hadi; Shahsavari, Mohammadhamed; Moradinejad, Ruhollah

2015-09-15

Inequality in function of the left and right bovine ovaries and uterine horns was evaluated in two separate experiments. In the first experiment (in vivo), the relationship between the left and right ovarian activities and reproductive indices was evaluated. Therefore, the total number of 1284 randomly chosen lactating dairy cows were examined from Day 50 to 60 postpartum, and according to the presence of an active CL on the ovaries, they were divided into 502 LCL3-cows and 782 RCL3-cows (cows with an active CL on the left [L] or right [R] ovary, respectively). To induce estrus synchronization and investigate the effects of PGF2α administration on the incidence of estrus in both LCL3-cows and RCL3-cows, the cows were treated with one luteolytic dose of PGF2α and were inseminated after observed estrus (via visual observation lasting at least 30 minutes three times a day). To investigate the effects of side of ovulation at the time of PGF2α administration on reproductive parameters, pregnancy diagnosis was performed 28 days after insemination (using ultrasound) and 42 days after insemination (using transrectal palpation). The results showed that the percentage of the RCL3-cows was greater than the LCL3-cows (60.9% vs. 39.1%, respectively). Furthermore, ovulations switching from the left to right ovary in two successive ovulations were greater than those that switched from the right to left ovary. On the other hand, the sex ratio (male percentage) in the right uterine horn was greater than that of the left one. In the second experiment (in vitro), the developmental potential of bovine oocytes derived from the left (L-oocytes) and right (R-oocytes) ovaries after in vitro embryo production and heterogeneity in the developmental competence of L-oocytes and R-oocytes using the brilliant cresyl blue staining test as a selection criterion were evaluated. Results of the in vitro experiment showed that the percentage of cleavage and blastocyst rate of R-oocytes were greater (P < 0.001) than those of L-oocytes. Moreover, it appears that the side of ovaries had greater effects on the developmental competence of oocytes than other factors associated with heterogeneity in the developmental competence of oocytes, which can be detected by the brilliant cresyl blue test. In conclusion, the results of the in vivo study confirmed the observations in previous studies in which the right ovarian response (distribution of ovulation) was superior to that of the left ones. Interestingly, the in vitro experiments for the first time clearly showed that more ovulation on the right side is not the only reason for this unequal activity. In fact, in cattle, the greater developmental potential of oocytes originating from right ovaries may cause superior activity of the right side, and the effect is even higher than the differences in ovulation response between the left and right ovaries. Copyright © 2015 Elsevier Inc. All rights reserved.

An Improved System for Generation of Diploid Cloned Porcine Embryos Using Induced Pluripotent Stem Cells Synchronized to Metaphase.

PubMed

Kim, Eunhye; Zheng, Zhong; Jeon, Yubyeol; Jin, Yong-Xun; Hwang, Seon-Ung; Cai, Lian; Lee, Chang-Kyu; Kim, Nam-Hyung; Hyun, Sang-Hwan

2016-01-01

Pigs provide outstanding models of human genetic diseases due to their striking similarities with human anatomy, physiology and genetics. Although transgenic pigs have been produced using genetically modified somatic cells and nuclear transfer (SCNT), the cloning efficiency was extremely low. Here, we report an improved method to produce diploid cloned embryos from porcine induced pluripotent stem cells (piPSCs), which were synchronized to the G2/M stage using a double blocking method with aphidicolin and nocodazole. The efficiency of this synchronization method on our piPSC lines was first tested. Then, we modified our traditional SCNT protocol to find a workable protocol. In particular, the removal of a 6DMAP treatment post-activation enhanced the extrusion rate of pseudo-second-polar bodies (p2PB) (81.3% vs. 15.8%, based on peak time, 4hpa). Moreover, an immediate activation method yielded significantly more blastocysts than delayed activation (31.3% vs. 16.0%, based on fused embryos). The immunofluorescent results confirmed the effect of the 6DMAP treatment removal, showing remarkable p2PB extrusion during a series of nuclear transfer procedures. The reconstructed embryos from metaphase piPSCs with our modified protocol demonstrated normal morphology at 2-cell, 4-cell and blastocyst stages and a high rate of normal karyotype. This study demonstrated a new and efficient way to produce viable cloned embryos from piPSCs when synchronized to the G2/M phase of the cell cycle, which may lead to opportunities to produce cloned pigs from piPSCs more efficiently.

Global synchronization algorithms for the Intel iPSC/860

NASA Technical Reports Server (NTRS)

Seidel, Steven R.; Davis, Mark A.

1992-01-01

In a distributed memory multicomputer that has no global clock, global processor synchronization can only be achieved through software. Global synchronization algorithms are used in tridiagonal systems solvers, CFD codes, sequence comparison algorithms, and sorting algorithms. They are also useful for event simulation, debugging, and for solving mutual exclusion problems. For the Intel iPSC/860 in particular, global synchronization can be used to ensure the most effective use of the communication network for operations such as the shift, where each processor in a one-dimensional array or ring concurrently sends a message to its right (or left) neighbor. Three global synchronization algorithms are considered for the iPSC/860: the gysnc() primitive provided by Intel, the PICL primitive sync0(), and a new recursive doubling synchronization (RDS) algorithm. The performance of these algorithms is compared to the performance predicted by communication models of both the long and forced message protocols. Measurements of the cost of shift operations preceded by global synchronization show that the RDS algorithm always synchronizes the nodes more precisely and costs only slightly more than the other two algorithms.

LH (Luteinizing Hormone) Test

MedlinePlus

... to predict ovulation by detecting a woman's monthly pre-ovulation LH surge. It indicates ovulation but cannot, however, be used to confirm that ovulation has occurred. Why would a man need a test for FSH and LH; I thought these were ...

Clomiphene citrate alternatives for the initial management of polycystic ovary syndrome: an evidence-based approach.

PubMed

Abu Hashim, Hatem

2012-06-01

Polycystic ovary syndrome (PCOS) is a prevalent and heterogeneous condition affecting 4-8% of reproductive age women. It is the most common cause of chronic anovulation and is associated with hyperandrogenemia. Clomiphene citrate (CC) is considered as the first-line therapy for ovulation induction in these patients. Despite progress in understanding the pathophysiology of PCOS over the past 20 years, many questions persist to the extent that PCOS was described as "A Riddle Wrapped in a Mystery inside an Enigma". On the other hand, a recent publication from the Centers for Disease Control suggested that CC may be associated with an increased risk of birth defects. The purpose of this review is to critically evaluate and summarize the current literature regarding CC alternatives for the initial management of PCOS focusing specifically on the roles of weight loss and other approaches to ovulation induction as insulin-sensitizing drugs, aromatase inhibitors, minimal stimulation protocol, gonadotrophins and surgery (laparoscopic ovarian drilling). Finally, the efficacy of intrauterine insemination with CC for the initial management of PCOS will be evaluated.

Gonadotropin-releasing hormone for infertility in women with primary hypothalamic amenorrhea. Toward a more-interventional approach.

PubMed

Kesrouani, A; Abdallah, M A; Attieh, E; Abboud, J; Atallah, D; Makhoul, C

2001-01-01

To assess the effectiveness of a protocol of pulsatile gonadotropin releasing-hormone (GnRH) in treating infertility in women with primary hypothalamic amenorrhea. Retrospective analysis of 44 cycles treated at an infertility center. Twenty-four patients with primary hypothalamic amenorrhea were treated intravenously with pulsatile GnRH using 5 micrograms per bolus every 90 minutes. Ultrasound monitoring and cervical assessment by Insler's scoring system allowed timed injection of human chorionic gonadotropin (hCG) and intrauterine insemination if needed. Luteal support was provided with hCG. The ovulation rate was 95% with the 5-microgram dose. A single follicle was produced in 91% of cycles. The overall pregnancy rate per ovulatory cycle was 45%, and the pregnancy rate per patient was 83%. In patients treated previously with exogenous gonadotropins, poor results were observed. Only one case of mild overstimulation was reported. Pulsatile GnRH is an effective and safe method of treating infertility in women with primary hypothalamic amenorrhea, thus simulating normal ovulation; however, more-interventional management, including the qualitative estrogenic response, may lead to optimal results and increase the pregnancy rate.

Expression of Na(+)/H(+) exchanger isoforms 1, 2, 3, and 4 in bovine endometrium and the influence of uterine pH at time of fixed-time AI of pregnancy success.

PubMed

Bolzenius, Jennifer K; Cushman, Robert A; Perry, George A

2016-08-01

Cows that exhibit estrus prior to fixed-time AI had increased sperm transport to the site of fertilization, and improved embryo quality on d 6 after insemination. Sperm transport is influenced by uterine pH, and research has reported that uterine pH decreased at onset of estrus, but must return to normal prior to ovulation. Therefore, the objectives of these studies were to investigate a possible mechanism for the regulation of uterine pH around the onset of estrus, and to determine if uterine pH at time of fixed-time AI influenced pregnancy success. In experiment 1, Angus-cross beef cows (n=40 and 28 in rep. 1 and 2, respectively) were synchronized with the PG 6-day CIDR protocol (PGF2α on d -9, GnRH and insertion of a CIDR on d -6, and PGF2α and CIDR removal on d 0). Cows were blocked by follicle size at time of CIDR removal, and uterine biopsies were collected at 0, 12, 24, 36, 48, 60 (Rep. 1), 72, 84, or 96h (Rep2) after CIDR removal, and total cellular RNA was extracted from all biopsies. Estrus was monitored by the HeatWatch Estrous Detection System. In experiment 2, 223 postpartum beef cows in 2 herds were synchronized with a fixed-time AI protocol (herd 1: n=97; CO-Synch plus CIDR protocol; herd 2: n=126; Co-synch protocol). Uterine pH was determined at time of AI (n=80 and 63 for herd 1 and 2, respectively), and estrus was monitored by visual estrus detection with the aid of an ESTROTECT estrous detection patches, and pregnancy was determined by transrectal ultrasonography. In experiment 1, there was a significant (P<0.01), quadratic relationship in expression of Na(+)/H(+) exchanger isoforms 1, 2, and 3 among animals that exhibited estrus, with expression greatest at time of CIDR removal, decreasing to the onset of estrus, and then increasing again following the onset of estrus. Among cows that did not exhibit estrus, the preceding relationship did not exist (P>0.46). In experiment 2, cows that had initiated estrus prior to fixed-time AI had decreased (P=0.01) uterine pH compared to cows that did not initiate estrus (6.78±0.03 and 6.89±0.03, respectively), and uterine pH at AI had an approximately linear effect on pregnancy success within the observed pH range. Furthermore, cows that initiated estrus prior to AI had increased (P=0.05) pregnancy success (52% vs. 38%) compared to cows that had not initiated estrus. In summary, expression of Na(+)/H(+) exchanger isoforms 1, 2, and 3 decreased after CIDR removal among cows that exhibited estrus, but did not change among cows that did not exhibit estrus. Additionally, as uterine pH decreased pregnancy success tended to increase (P=0.076, logistics regression). Thus, Na(+)/H(+) exchanger isoforms 1, 2, and 3 appear to be key regulators of uterine pH around the onset of estrus, and this change in uterine pH is critical for pregnancy success. Expression of Na(+)/H(+) exchanger isoforms 1, 2, and 3 decreased after CIDR removal among cows that exhibited estrus, but did not change among cows that did not exhibit estrus, and as uterine pH decreased, pregnancy success tended to increase. Copyright © 2016 Elsevier B.V. All rights reserved.

Effect of the Camelid’s Seminal Plasma Ovulation-Inducing Factor/β-NGF: A Kisspeptin Target Hypothesis

PubMed Central

El Allali, Khalid; El Bousmaki, Najlae; Ainani, Hassan; Simonneaux, Valérie

2017-01-01

Female mammals are classified into spontaneous and induced ovulators based on the mechanism eliciting ovulation. Ovulation in spontaneous species (e.g., human, sheep, cattle, horse, pigs, and most rodents) occurs at regular intervals and depends upon the circulating estradiol. However, in induced ovulators (e.g., rabbits, ferrets, cats, and camelids), ovulation is associated with coitus. In the later, various factors have been proposed to trigger ovulation, including auditory, visual, olfactory, and mechanic stimuli. However, other studies have identified a biochemical component in the semen of induced ovulators responsible for the induction of ovulation and named accordingly ovulation-inducing factor (OIF). In camelids, intramuscular or intrauterine administration of seminal plasma (SP) was shown to induce the preovulatory luteinizing hormone (LH) surge followed by ovulation and subsequent formation of corpus luteum. Recently, this OIF has been identified from SP as a neurotrophin, the β subunit of nerve growth factor (β-NGF). β-NGF is well known as promoting neuron survival and growth, but in this case, it appears to induce ovulation through an endocrine mode of action. Indeed, β-NGF may be absorbed through the endometrium to be conveyed, via the blood stream, to the central structures regulating the LH preovulatory surge. In this review, we provide a summary of the most relevant results obtained in the field, and we propose a working hypothesis for the central action of β-NGF based on our recent demonstration of the presence of neurons expressing kisspeptin, a potent stimulator of GnRH/LH, in the camel hypothalamus. PMID:28713816

Effect of the Camelid's Seminal Plasma Ovulation-Inducing Factor/β-NGF: A Kisspeptin Target Hypothesis.

PubMed

El Allali, Khalid; El Bousmaki, Najlae; Ainani, Hassan; Simonneaux, Valérie

2017-01-01

Female mammals are classified into spontaneous and induced ovulators based on the mechanism eliciting ovulation. Ovulation in spontaneous species (e.g., human, sheep, cattle, horse, pigs, and most rodents) occurs at regular intervals and depends upon the circulating estradiol. However, in induced ovulators (e.g., rabbits, ferrets, cats, and camelids), ovulation is associated with coitus. In the later, various factors have been proposed to trigger ovulation, including auditory, visual, olfactory, and mechanic stimuli. However, other studies have identified a biochemical component in the semen of induced ovulators responsible for the induction of ovulation and named accordingly ovulation-inducing factor (OIF). In camelids, intramuscular or intrauterine administration of seminal plasma (SP) was shown to induce the preovulatory luteinizing hormone (LH) surge followed by ovulation and subsequent formation of corpus luteum. Recently, this OIF has been identified from SP as a neurotrophin, the β subunit of nerve growth factor (β-NGF). β-NGF is well known as promoting neuron survival and growth, but in this case, it appears to induce ovulation through an endocrine mode of action. Indeed, β-NGF may be absorbed through the endometrium to be conveyed, via the blood stream, to the central structures regulating the LH preovulatory surge. In this review, we provide a summary of the most relevant results obtained in the field, and we propose a working hypothesis for the central action of β-NGF based on our recent demonstration of the presence of neurons expressing kisspeptin, a potent stimulator of GnRH/LH, in the camel hypothalamus.

Effect of ovule position within the pod on the probability of seed production in Bauhinia ungulata (Fabaceae).

PubMed

Mena-Alí, Jorge I; Rocha, Oscar J

2005-02-01

It has been claimed that ovules linearly ordered within a fruit differ in their probabilities of reaching maturity. This was investigated by studying the effect the position of an ovule within the pod has on seed abortion and seed production in Bauhinia ungulata. Fruits collected during the dry seasons of 1999, 2000 and 2001 were opened, and the number, position and status of each ovule within the fruit were recorded. A GLM model was used to assess the effects of population, tree identity and ovule position within the pod on ovule fertilization, seed abortion, seed damage and seed maturation in two populations of B. ungulata. Nearly 30% of the ovules were not fertilized in 1999; this percentage dropped to 5% the following two years. Seed abortion (50%) and seed damage (15%) were the same every year during the study period. Only 15% of the initial ovules developed into mature seeds in 1999; this value increased to 35% in 2000 and 2001. However, seed survivorship was dependent on the position of the ovule within the pod; non-fertilized and early aborted ovules were found more often near the basal end of the ovary. The frequency of seed damage was not affected by position. Mature seeds were found mainly in the stylar half of fruits, where ovules are likely to be fertilized by fast pollen tubes. The pattern of seed production in B. ungulata is non-random but is dependent upon the position of the ovule within the pod. The results suggest that the seeds produced within a fruit might differ in their vigour.

Baseline AMH Level Associated With Ovulation Following Ovulation Induction in Women With Polycystic Ovary Syndrome.

PubMed

Mumford, Sunni L; Legro, Richard S; Diamond, Michael P; Coutifaris, Christos; Steiner, Anne Z; Schlaff, William D; Alvero, Ruben; Christman, Gregory M; Casson, Peter R; Huang, Hao; Santoro, Nanette; Eisenberg, Esther; Zhang, Heping; Cedars, Marcelle I

2016-09-01

Anti-Müllerian hormone (AMH) reduces aromatase activity and sensitivity of follicles to FSH stimulation. Therefore, elevated serum AMH may indicate a higher threshold for response to ovulation induction in women with polycystic ovary syndrome (PCOS). This study sought to determine the association between AMH levels and ovulatory response to treatment among the women enrolled into the Pregnancy in PCOS II (PPCOS II) trial. This was a secondary analysis of data from a randomized clinical trial in academic health centers throughout the United States Participants: A total of 748 women age 18-40 years, with PCOS and measured AMH levels at baseline, were included in this study. Couples were followed for up to five treatment cycles to determine ovulation (midluteal serum progesterone > 5 ng/mL) and the dose required to achieve ovulation. A lower mean AMH and AMH per follicle was observed among women who ovulated compared with women who never achieved ovulation during the study (geometric mean AMH, 5.54 vs 7.35 ng/mL; P = .0001; geometric mean AMH per follicle, 0.14 vs 0.18; P = .01) after adjustment for age, body mass index, T, and insulin level. As AMH levels increased, the dose of ovulation induction medication needed to achieve ovulation also increased. No associations were observed between antral follicle count and ovulation. These results suggest that high serum AMH is associated with a reduced response to ovulation induction among women with PCOS. Women with higher AMH levels may require higher doses of medication to achieve ovulation.

Synchronous colonic tumours of dual pathology.

PubMed

Basu, S; Selvachandran, S N; Cade, D

2001-05-01

Synchronous colonic tumours of dual pathology are extremely rare. A review of the literature revealed that few cases have been reported to date. Because of their rarity and lack of specific symptoms, preoperative diagnosis is not easy and there is no protocol as yet for the ideal management of these cases. We present such a case which was treated by a combination of surgery and chemotherapy.

A Novel Group Coordination Protocol for Collaborative Multimedia Systems

DTIC Science & Technology

1998-01-01

technology have advanced considerably, ef- ficient group coordination support for applications characterized by synchronous and wide-area groupwork is...As a component within a general coordination architecture for many-to-many groupwork , floor control coexists with proto- cols for reliable ordered...multicast and media synchronization at a sub-application level. Orchestration of multiparty groupwork with fine-grained and fair floor control is an

How the ovules get enclosed in magnoliaceous carpels.

PubMed

Zhang, Xin; Liu, Wenzhe; Wang, Xin

2017-01-01

Angiosperms distinguish themselves from gymnosperms by their ovules that are enclosed before pollination. However, how the ovules get enclosed in angiosperms remains a mystery, especially for Magnoliaceae. The only key to this mystery is finding a series of carpels transitional from fully closed with enclosed ovules to open with naked ovules. We use routine paraffin section technology, LM, SEM to document the morphology and anatomy of carpel variation in Michelia figo (Magnoliaceae). A series of carpel variations within a single flower of Michelia figo (Magnoliaceae) are documented, in which the ovules are exposed in atypical carpels. These atypical and typical carpels for the first time demonstrate clearly how the naked ovule get enclosed. Each atypical carpel, with naked ovules, clearly comprises two parts, namely, subtending foliar part and branches bearing ovules, suggesting that a typical carpel is actually an end-product of the fusion between the ovuliferous branches and subtending foliar parts. The only difference among these carpels is the extent of fusion between these two parts. This generalization is in full agreement with the molecular genetic studies on angiosperm flowers.

Superovulation induction in the house musk shrew (Suncus murinus).

PubMed

Matsuzaki, T; Matsuzaki, K; Yokoyama, M; Yamada, S; Saito, M

1997-07-01

The number of ovulated oocytes in the adult house musk shrews was examined by natural mating. The positive rate of ovulation was 83.3%, and the mean number of ovulated oocytes was 4.4 +/- 1.9 (Mean +/- SD). The induction of superovulation was examined by administering either pregnant mare's serum gonadotropin (PMSG) or human chorionic gonadotropin (hCG), exogenous gonadotropin, to house musk shrews. As a result, the number of ovulated oocytes were within the number of oocytes ovulated spontaneously. The method of superovulation induction by administering both PMSG and hCG to house musk shrews was investigated. In the group intraperitoneally with 7.5 i.u. of PMSG followed by 7.5 i.u. of hCG 48 hr later, the positive rate of ovulation was as high as 94.6% and the mean number of ovulated oocytes was 11.7 +/- 13.4. Moreover, in 15 out of these 35 animals positive for ovulation, 10 oocytes or more were observed and the mean number of ovulated oocytes was 21.0 +/- 16.5, showing the superovulatory response. In the group of 5.0 i.u. PMSG and 5.0 i.u. hCG injected at an interval of 72 hr, every animal was induced to ovulate and the mean number of ovulated oocytes was 41.3 +/- 19.9. Thus, the injection of PMSG and hCG at a longer interval increased the number of superovulated oocytes. Furthermore, 97.5% of eggs recovered from superovulating animals contained cumulus cells.

Finite-time synchronization for second-order nonlinear multi-agent system via pinning exponent sliding mode control.

PubMed

Hou, Huazhou; Zhang, Qingling

2016-11-01

In this paper we investigate the finite-time synchronization for second-order multi-agent system via pinning exponent sliding mode control. Firstly, for the nonlinear multi-agent system, differential mean value theorem is employed to transfer the nonlinear system into linear system, then, by pinning only one node in the system with novel exponent sliding mode control, we can achieve synchronization in finite time. Secondly, considering the 3-DOF helicopter system with nonlinear dynamics and disturbances, the novel exponent sliding mode control protocol is applied to only one node to achieve the synchronization. Finally, the simulation results show the effectiveness and the advantages of the proposed method. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

Effects of breed, age, season, and multiple ovulations on cyclic, PGF2α-induced, and postpartum estrus characteristics in Spanish jennies.

PubMed

Perez-Marin, C C; Galisteo, I; Perez-Rico, A; Galisteo, J

2016-04-01

This retrospective, population-based, cross-sectional study analyzed data for a total of 104 jennies reared in southern Spain over the period 1995 to 2014. Intervals to ovulation and incidence of multiple ovulation and pregnancy were charted for spontaneous, PGF2α-induced, and postpartum estrous cycles. In spontaneous estrous cycles, the interovulatory interval varied as a function of breed (P < 0.03) and month of ovulation (P < 0.01), and duration of estrus signs was longer in older jennies (0.04). Spontaneous cycles were also associated with higher ovulation rates from September to January (P < 0.006). When PGF2α was used to induce the estrus, not only did estrus signs last longer in old (P < 0.004) and in polyovular (0.02) jennies but old jennies also displayed significantly higher ovulation rates (P < 0.03). In postpartum jennies, no variations were observed as a function of any of the independent variables analyzed. Comparison of ovulation rates between different types of cycle revealed that postpartum jennies exhibited significantly lower ovulation rates (1.32 ± 0.07) and a lower incidence of multiple ovulation (30.4%) than spontaneous (1.62 ± 0.04, 55.0%) and PGF2α-induced (1.74 ± 0.08, 65.5%) groups. No differences were observed in the incidence of ovulation or pregnancy depending on the location of ovulation in polyovular cycles, and ovulation occurred at similar rates in the right and left ovaries. These findings shed further light on reproductive physiology in jennies and may be of value in improving animal management. Copyright © 2016 Elsevier Inc. All rights reserved.

Effect of Ovule Position within the Pod on the Probability of Seed Production in Bauhinia ungulata (Fabaceae)

PubMed Central

MENA-ALÍ, JORGE I.; ROCHA, OSCAR J.

2004-01-01

• Background and Aims It has been claimed that ovules linearly ordered within a fruit differ in their probabilities of reaching maturity. This was investigated by studying the effect the position of an ovule within the pod has on seed abortion and seed production in Bauhinia ungulata. • Methods Fruits collected during the dry seasons of 1999, 2000 and 2001 were opened, and the number, position and status of each ovule within the fruit were recorded. A GLM model was used to assess the effects of population, tree identity and ovule position within the pod on ovule fertilization, seed abortion, seed damage and seed maturation in two populations of B. ungulata. • Key Results Nearly 30 % of the ovules were not fertilized in 1999; this percentage dropped to 5 % the following two years. Seed abortion (50 %) and seed damage (15 %) were the same every year during the study period. Only 15 % of the initial ovules developed into mature seeds in 1999; this value increased to 35 % in 2000 and 2001. However, seed survivorship was dependent on the position of the ovule within the pod; non-fertilized and early aborted ovules were found more often near the basal end of the ovary. The frequency of seed damage was not affected by position. Mature seeds were found mainly in the stylar half of fruits, where ovules are likely to be fertilized by fast pollen tubes. • Conclusions The pattern of seed production in B. ungulata is non-random but is dependent upon the position of the ovule within the pod. The results suggest that the seeds produced within a fruit might differ in their vigour. PMID:15596452

DOE Office of Scientific and Technical Information (OSTI.GOV)

Duan, Sisi; Nicely, Lucas D; Zhang, Haibin

Modern large-scale networks require the ability to withstand arbitrary failures (i.e., Byzantine failures). Byzantine reliable broadcast algorithms can be used to reliably disseminate information in the presence of Byzantine failures. We design a novel Byzantine reliable broadcast protocol for loosely connected and synchronous networks. While previous such protocols all assume correct senders, our protocol is the first to handle Byzantine senders. To achieve this goal, we have developed new techniques for fault detection and fault tolerance. Our protocol is efficient, and under normal circumstances, no expensive public-key cryptographic operations are used. We implement and evaluate our protocol, demonstrating that ourmore » protocol has high throughput and is superior to the existing protocols in uncivil executions.« less

Interactions among Genes Regulating Ovule Development in Arabidopsis Thaliana

PubMed Central

Baker, S. C.; Robinson-Beers, K.; Villanueva, J. M.; Gaiser, J. C.; Gasser, C. S.

1997-01-01

The INNER NO OUTER (INO) and AINTEGUMENTA (ANT) genes are essential for ovule integument development in Arabidopsis thaliana. Ovules of ino mutants initiate two integument primordia, but the outer integument primordium forms on the opposite side of the ovule from the normal location and undergoes no further development. The inner integument appears to develop normally, resulting in erect, unitegmic ovules that resemble those of gymnosperms. ino plants are partially fertile and produce seeds with altered surface topography, demonstrating a lineage dependence in development of the testa. ant mutations affect initiation of both integuments. The strongest of five new ant alleles we have isolated produces ovules that lack integuments and fail to complete megasporogenesis. ant mutations also affect flower development, resulting in narrow petals and the absence of one or both lateral stamens. Characterization of double mutants between ant, ino and other mutations affecting ovule development has enabled the construction of a model for genetic control of ovule development. This model proposes parallel independent regulatory pathways for a number of aspects of this process, a dependence on the presence of an inner integument for development of the embryo sac, and the existence of additional genes regulating ovule development. PMID:9093862

Cell Cycle Synchronization of HeLa Cells to Assay EGFR Pathway Activation.

PubMed

Wee, Ping; Wang, Zhixiang

2017-01-01

Progression through the cell cycle causes changes in the cell's signaling pathways that can alter EGFR signal transduction. Here, we describe drug-derived protocols to synchronize HeLa cells in various phases of the cell cycle, including G1 phase, S phase, G2 phase, and mitosis, specifically in the mitotic stages of prometaphase, metaphase, and anaphase/telophase. The synchronization procedures are designed to allow synchronized cells to be treated for EGF and collected for the purpose of Western blotting for EGFR signal transduction components.S phase synchronization is performed by thymidine block, G2 phase with roscovitine, prometaphase with nocodazole, metaphase with MG132, and anaphase/telophase with blebbistatin. G1 phase synchronization is performed by culturing synchronized mitotic cells obtained by mitotic shake-off. We also provide methods to validate the synchronization methods. For validation by Western blotting, we provide the temporal expression of various cell cycle markers that are used to check the quality of the synchronization. For validation of mitotic synchronization by microscopy, we provide a guide that describes the physical properties of each mitotic stage, using their cellular morphology and DNA appearance. For validation by flow cytometry, we describe the use of imaging flow cytometry to distinguish between the phases of the cell cycle, including between each stage of mitosis.

Hormonal profile and follicular dynamics concurrent with CIDR and insulin modified Ovsync TAI programs and their impacts on the fertility response in buffaloes.

PubMed

Ramoun, A A; Emara, A M; Heleil, B A; Darweish, S A; Abou-Ghait, H A

2017-12-01

Fifty one cyclic Egyptian buffaloes were used to study the hormonal profile and follicular dynamics concurrent with CIDR and insulin modified Ovsync TAI programs and their impacts on the consequent fertility responses. The buffaloes were randomly assigned into 3 ovulation synchronization protocols: Ovsync-alone (n = 13, control) CIDR-sync (n = 20) and Insulin-sync (n = 18). Ovsync-alone protocol consisted of two im injections of 20 μg bueserlin (GnRHa) on Day 0 (GnRH 1) and on Day 9 (GnRH 2) with an im injection of 500 μg of cloprostenol sodium (PGF 2 α) on Day 7. The CIDR-sync protocol consisted of the same treatment protocol as in Ovsync in addition to intra-vaginal insertion of CIDR (contains 1.38 gm of progesterone) on Day 0 followed by removal on Day 7. The Insulin-sync protocol consisted of the same treatment protocol as in Ovsync plus 3 sc injections of insulin at a dose of 0.25 i.u/1 kg, on Days 7, 8, and 9. Buffaloes in all groups were inseminated 16 h after GnRH2 by the same inseminator using frozen semen in straws. Blood samples were collected on Days 0, 3, 5 for serum progesterone assay and on Day 9 to measure serum concentrations of estradiol, insulin and IGF-1. Transrectal ultrasonographic scanning of the ovaries was conducted on Days 7, 8 and 9 to record the diameter of the largest follicle. Pregnancy diagnosis was conducted on Day 30 post-TAI by trans-rectal ultrasonographic scanning of the uterus to calculate conception rate. The serum progesterone concentration showed an increase (p < 0.01) in pregnant compared with non-pregnant buffaloes in both Ovsync-alone and Insulin-sync groups, but not in CIDR-sync group (p > 0.05) on Days 3 and 5. The serum estradiol concentration on Day 9 showed an increase (p < 0.01) in pregnant compared with the non-pregnant buffaloes in all of the treated groups. In Insulin-sync and Ovsync-alone groups, the diameter of the largest follicle (LF) was larger (p < 0.01) in pregnant compared with non-pregnant buffaloes, but in CIDR-sync, the diameter of the (LF) was larger (p < 0.01) in non-pregnant compared with pregnant buffaloes. Also, the results showed that the greatest diameter of LF was observed in pregnant buffaloes in Insulin-sync compared with either pregnant or non-pregnant buffaloes in all groups. It is concluded that modified CIDR-sync and Insulin-sync could improve fertility response through modulating hormonal profile and follicular dynamics in buffaloes during low breeding season. Copyright © 2017 Elsevier Inc. All rights reserved.

Software Design Document MCC CSCI (1). Volume 1 Sections 1.0-2.18

DTIC Science & Technology

1991-06-01

AssociationUserProtocol /simnet/common!include/prot ____________________ ____________________ ocol/p assoc.h Primitive long Standard C type...Information. 2.2.1.4.2 ProcessMessage ProcessMessage processes a message from another process. type describes the message as either one-way, a synchronous or...Macintosh Consoles. This is sometimes necessary due to normal clock skew so that operations among the MCC components will remain synchronized . This

Assessment of DoD and Industry Networks for Computer Aided Logistics Support (CALS) Telecommunications.

DTIC Science & Technology

1987-06-01

International Business Machines ( IBM ) Corporation compatible synchronous terminals (2780/3780/327X), and the Federal Data Corporation (FDC) has developed...the interfaces for Burroughs look-alike asynchronous and synchronous terminals. Basically, this means that the IBM and Burroughs protocols are...and other vendor computers, such as IBM , UNIVAC, and Honeywell. The Navy has developed file transfer capabilities between Tandem and Burroughs. These

Leader-Follower Output Synchronization of Linear Heterogeneous Systems With Active Leader Using Reinforcement Learning.

PubMed

Yang, Yongliang; Modares, Hamidreza; Wunsch, Donald C; Yin, Yixin

2018-06-01

This paper develops optimal control protocols for the distributed output synchronization problem of leader-follower multiagent systems with an active leader. Agents are assumed to be heterogeneous with different dynamics and dimensions. The desired trajectory is assumed to be preplanned and is generated by the leader. Other follower agents autonomously synchronize to the leader by interacting with each other using a communication network. The leader is assumed to be active in the sense that it has a nonzero control input so that it can act independently and update its control to keep the followers away from possible danger. A distributed observer is first designed to estimate the leader's state and generate the reference signal for each follower. Then, the output synchronization of leader-follower systems with an active leader is formulated as a distributed optimal tracking problem, and inhomogeneous algebraic Riccati equations (AREs) are derived to solve it. The resulting distributed optimal control protocols not only minimize the steady-state error but also optimize the transient response of the agents. An off-policy reinforcement learning algorithm is developed to solve the inhomogeneous AREs online in real time and without requiring any knowledge of the agents' dynamics. Finally, two simulation examples are conducted to illustrate the effectiveness of the proposed algorithm.

Time Warp Operating System (TWOS)

NASA Technical Reports Server (NTRS)

Bellenot, Steven F.

1993-01-01

Designed to support parallel discrete-event simulation, TWOS is complete implementation of Time Warp mechanism - distributed protocol for virtual time synchronization based on process rollback and message annihilation.

Face-to-Face versus Computer-Mediated Discussion of Teaching Cases: Impacts on Preservice Teachers' Engagement, Critical Analyses, and Self-Efficacy

ERIC Educational Resources Information Center

PytlikZillig, Lisa M.; Horn, Christy A.; Bruning, Roger; Bell, Stephanie; Liu, Xiongyi; Siwatu, Kamau O.; Bodvarsson, Mary C.; Kim, Doyoung; Carlson, Deborah

2011-01-01

Two frequently-used discussion protocols were investigated as part of a program to implement teaching cases in undergraduate educational psychology classes designed for preservice teachers. One protocol involved synchronous face-to-face (FTF) discussion of teaching cases, which occurred in class after students had individually completed written…

An improved embryo-rescue protocol for hybrid progeny from seedless Vitis vinifera grapes × wild Chinese Vitis species.

PubMed

Li, Gui Rong; Ji, Wei; Wang, Gang; Zhang, Jian Xia; Wang, Yue Jin

A highly efficient technique of embryo rescue is critical when using stenospermocarpic Vitis vinifera cultivars (female parents) to breed novel, disease-resistant, seedless grape cultivars by hybridizing with wild Chinese Vitis species (male parents) having many disease-resistance alleles. The effects of various factors on the improvement of embryo formation, germination, and plantlet development for seven hybrid combinations were studied. The results indicated that Beichun and Shuangyou were the best male parents. The best sampling time for ovule inoculation differed among the female parents. When hybrid ovules were cultured on a double-phase medium with five different solid medium types, percent embryo formation was highest (11.3-28.3%) on a modified MM3 medium. Percentages of embryo germination (15.4-55.4%) and plantlet development (11.15-44.6%) were all highest when embryos were cultured on Woody Plant Medium + 5.7 μM indole-3-acetic acid + 4.4 μM 6-benzylaminopurine + 1.4 μM gibberellic acid + 2% sucrose + 0.05% casein hydrolysate + 0.3% activated charcoal + 0.7% agar. In the absence of other amino acids, the addition of proline significantly increased embryo formation (36.1%), embryo germination (64.6%), and plantlet development (90.5%). A highly efficient protocol has been developed for hybrid embryo rescue from seedless V. vinifera grapes × wild Chinese Vitis species that results in a significant improvement in breeding efficiency for new disease-resistant seedless grapes.

An adaptive transmission protocol for managing dynamic shared states in collaborative surgical simulation.

PubMed

Qin, J; Choi, K S; Ho, Simon S M; Heng, P A

2008-01-01

A force prediction algorithm is proposed to facilitate virtual-reality (VR) based collaborative surgical simulation by reducing the effect of network latencies. State regeneration is used to correct the estimated prediction. This algorithm is incorporated into an adaptive transmission protocol in which auxiliary features such as view synchronization and coupling control are equipped to ensure the system consistency. We implemented this protocol using multi-threaded technique on a cluster-based network architecture.

Effectiveness of a short-term treatment with progesterone injections on synchrony of lambing and fertility in tropical hair sheep.

PubMed

Knights, Marlon; Ramgattie, Reeza; Siew, Narendra; Singh-Knights, Doolarie; Bourne, Gregory

2011-06-01

The efficacy of using a low cost system for delivering progesterone as part of an estrous synchronization protocol in sheep was evaluated. In experiment 1, Barbados Black Belly ewes (n=34) and ewe lambs (n=35; 37.5±0.9 kg) were assigned to be untreated, control animals (C), or to receive PGF(2α) on d0 (PG), or receive two injections of progesterone (200mg, i.m. each) on D -5 and on D -2.5, prior to PGF(2α), on D 0 (2PPG). Treatment with 2PPG increased the proportion of animals lambing to the first service (P<0.05), an effect that was greater in ewe lambs than ewes (treatment × parity; P<0.05). The interval from ram introduction to lambing and the mean lambing day was less (P=0.04) in the 2PPG-treated animals compared to control animals. In Experiment 2, lactating ewes from experiment 1 (n=61) 60-85 days postpartum were assigned within parity and number of lambs reared to remain nursing (S; n=29) or weaned (W; n=32) 3 weeks prior to treatment with the 2PPG protocol. There was no effect of treatment on the proportion of animals lambing to the first service or overall, interval from ram introduction to lambing and lambing interval. An 8-month lambing interval was observed in ewes in which estrus was synchronized regardless of physiological state. In conclusion, the two-progesterone injection synchronization protocol may be used as a practical low cost and efficient method of synchronizing estrus to reduce the lambing interval and maximize productivity in tropical breeds of sheep. Copyright © 2011 Elsevier B.V. All rights reserved.

Differences in uterine immunoexpression of PR, ERα and OTR when comparing prostaglandin- to progestagen-based protocols for ovine estrus synchronization.

PubMed

Ruiz-González, I; Sánchez, M A; García-Palencia, P; Sánchez, B; García-Fernández, R A; González-Bulnes, A; Flores, J M

2012-07-01

The aim of this work was to compare PR, ERα and OTR uterine expression between days 9 and 21 of pregnancy in ewes whose estrus had been synchronized with two different protocols. Sixty-four adult Manchega ewes were synchronized with either conventional progestagens (P) or prostaglandin analogues (PG), and mated. Uterine samples were obtained from pregnant animals (group P, n=24; group PG, n=25) on days 9 post coitus (pc), 13pc, 15pc, 17pc and 21pc. Immunohistochemical detection of progesterone receptor (PR), estrogen receptor-α (ERα) and oxytocin receptor (OTR) was assessed in different uterine cell compartments including luminal and glandular epithelium, stroma and myometrium. Interaction day × treatment was obtained when assessing PR expression in the caruncular stroma (P=0.027) and myometrium (P=0.000), as well as for ERα in the superficial stroma (P=0.05). Significant "day post coitus" effect was found regarding to PR (P<0.01, with the exception of the superficial stroma, deep stroma and myometrium), ERα (P<0.01), and OTR (P<0.05, except in the deep compartments). No significant "treatment" effect was found for PR, ERα or OTR protein immunoexpression. This study supports the implication of PR, ERα and OTR within days 9-21 of the ovine pregnancy. Moreover, different expression pattern of PR and ERα proteins has been found between treatments in various compartments studied. Collectively, these results indicate that PR, ERα and OTR expression during early pregnancy is similar between ewes treated with either progestagens or prostaglandin analogues-based protocols for estrus synchronization. Copyright © 2012 Elsevier B.V. All rights reserved.

A precise time synchronization method for 5G based on radio-over-fiber network with SDN controller

NASA Astrophysics Data System (ADS)

He, Linkuan; Wei, Baoguo; Yang, Hui; Yu, Ao; Wang, Zhengyong; Zhang, Jie

2018-02-01

There is an increasing demand on accurate time synchronization with the growing bandwidth of network service for 5G. In 5G network, it's necessary for base station to achieve accurate time synchronization to guarantee the quality of communication. In order to keep accuracy time for 5G network, we propose a time synchronization system for satellite ground station based on radio-over-fiber network (RoFN) with software defined optical network (SDON) controller. The advantage of this method is to improve the accuracy of time synchronization of ground station. The IEEE 1588 time synchronization protocol can solve the problems of high cost and lack of precision. However, in the process of time synchronization, distortion exists during the transmission of digital time signal. RoF uses analog optical transmission links and therefore analog transmission can be implemented among ground stations instead of digital transmission, which means distortion and bandwidth waste in the process of digital synchronization can be avoided. Additionally, the thought of SDN, software defined network, can optimize RoFN with centralized control and simplifying base station. Related simulation had been carried out to prove its superiority.

Ovulation induction by antiestrogens in an Indian tropical vespertillionid bat, Scotophilus heathi.

PubMed

Pakrasi, Pranab Lal; Tiwari, Anjana

2006-11-02

The ovulation induction property of ICI 182,780 a pure antiestrogen and enclomiphene citrate (ENC) was carried out in Scotophilus heathi, an Indian tropical vespertillionid bat, during December to February i.e., preovulatory period. This bat ovulates two ova naturally and shows ovulatory asynchrony. The study showed that 100 ìg of ENC followed by 10 IU hCG resulted in significantly lower number of ovulation. Whereas, the pure antiestrogen ICI 182,780 at a dose of 100 ìg followed by 10 IU hCG resulted in ovulation induction (4.2 +/- 0.4), which is significantly different in comparison to other groups. This is possibly the first report of ovulation induction using this pure antiestrogen i.e., ICI 182,780 in any bat as well as in any animal model that exhibits temporary anovulation similar to polycystic ovary disease (PCOD). This antiestrogen may be useful to induce ovulation in PCOD patients.

Isolation of Individual Egg Cells and Zygotes in Alstroemeria Followed by Manual Selection with a Microcapillary-connected Micropump

PubMed Central

HOSHINO, YOICHIRO; MURATA, NAHO; SHINODA, KOICHI

2006-01-01

• Aims To develop a procedure for isolating living egg cells and zygotes from Alstroemeria ovules. • Scope An attempt was made to isolate egg cells and zygotes from the ovules of Alstroemeria aurea. The ovules were histologically observed using a clearing procedure which revealed the localization and sizes of the embryo sacs and egg apparatus within the ovules. For the isolation of egg cells, ovules were cut into sections with a surgical blade and treated with an enzyme solution. Subsequently, these ovule sections were dissected using a glass needle under an inverted microscope. Egg cells successfully isolated by this procedure were collected using microcapillaries connected to a micropump. For zygote isolation, ovules were excised from ovaries 24 h after self-pollination. By treating excised ovules with an enzyme solution and subsequently dissecting them using a glass needle, zygotes were successfully isolated from the ovules and collected with a microcapillary. The isolated zygotes were associated with pollen tubes and one of the synergids. Egg cells and zygotes were viable for up to 2 h following isolation, as determined by fluorescein diacetate staining. • Conclusions The procedures for isolating egg cells and zygotes in Alstroemeria were established, and each egg cell and zygote was captured with a microcapillary. PMID:16621859

The evolution of ovule number and flower size in wind-pollinated plants.

PubMed

Friedman, Jannice; Barrett, Spencer C H

2011-02-01

In angiosperms, ovules are "packaged" within individual flowers, and an optimal strategy should occur depending on pollination and resource conditions. In animal-pollinated species, wide variation in ovule number per flower occurs, and this contrasts with wind-pollinated plants, where most species possess uniovulate flowers. This pattern is usually explained as an adaptive response to low pollen receipt in wind-pollinated species. Here, we develop a phenotypic model for the evolution of ovule number per flower that incorporates the aerodynamics of pollen capture and a fixed resource pool for provisioning of flowers, ovules, and seeds. Our results challenge the prevailing explanation for the association between uniovulate flowers and wind pollination. We demonstrate that when flowers are small and inexpensive, as they are in wind-pollinated species, ovule number should be minimized and lower than the average number of pollen tubes per style, even under stochastic pollination and fertilization regimes. The model predicts that plants benefit from producing many small inexpensive flowers, even though some flowers capture too few pollen grains to fertilize their ovules. Wind-pollinated plants with numerous flowers distributed throughout the inflorescence, each with a single ovule or a few ovules, sample more of the airstream, and this should maximize pollen capture and seed production.

Effect of exogenous progesterone administration on luteal sensitivity to PGF during the early development of the corpus luteum in mares and cows.

PubMed

Garcia-Muñoz, A; Valldecabres-Torres, X; Newcombe, J R; Cuervo-Arango, J; Garcia-Rosello, E

2017-12-01

The objective of this study was to determine the effect of exogenous progesterone administration at ovulation and during the early development of the CL, on its future sensitivity to a single administration of PGF2a in mares and cows. Horse Retrospective reproductive data from an equine clinic in the UK during three breeding seasons were used. Mares were divided into: control group, cycles with single ovulations; double ovulation group cycles with asynchronous double ovulations; and PRID group: cycles with single ovulations and treatment with intravaginal progesterone device (CIDR) immediately after the ovulation. All mares were treated with d-cloprostenol (PGF) at either: (i) 88 hr; (ii) 96 hr; (iii) 104 hr; or (iv) 112 hr after the last ovulation. Cattle A total of nine non-lactating Holstein cows were used. All cows were administered PGF14 d apart and allocated to one of two groups control group GnRH was administered 56 hr after the second PGF administration. CIDR group CIDR was inserted at the same time of GnRH administration. All cows were administered PGF at 120 hr post-ovulation. The complete luteolysis rate of mares with double ovulation (66.7%) and those treated with exogenous progesterone (68.4%) was significantly higher than the rate of mares with single ovulation (35.6%) at 104 hr. In the cow, however, the treatment with CIDR did not increase the luteolytic response in cows treated at 120 hr post-ovulation. In conclusion, the degree of complete luteolysis can be influenced by increasing the concentration of progesterone during the early luteal development in mares. © 2017 Blackwell Verlag GmbH.

Development and fate of the postovulatory follicle complex, postovulatory follicle, and observations on folliculogenesis and oocyte atresia in ovulated common snook, Centropomus undecimalis (Bloch, 1792).

PubMed

Grier, Harry J; Neidig, Carole L; Quagio-Grassiotto, Irani

2017-04-01

The common snook, Centropomus undecimalis, was induced to ovulate using a time-release, GnRH analogue. Ovulation occurred the afternoon or evening the day after hormone administration. The time of ovulation was established within half an hour. At ovulation, three fish per time-group were divided into 0, 6, 12, 18 hr and one thru five days post-ovulation to study changes in the postovulatory follicle complex (POC). Histology of the ovaries revealed changes in the POC, postovulatory follicle (POF) and oocyte atresia through five days post-ovulation. Within 24 hr, nuclei of the POF cells lost their initial spherical or oval configuration, and by four days the basement membrane within the POC had fragmented. There was a temporal separation between ovulation and post-ovulation folliculogenesis; that is, in that the formation of new follicles commenced within the germinal epithelium between 12-48 hrs after ovulation. Morphology of the POC was best revealed with the reticulin stain; it is composed of the POF and postovulatory theca (POT). These are separated by a basement membrane, reflecting the origin of a follicle from a germinal epithelium while the theca is derived from stroma. The POF is composed of the former follicle cells that surrounded and contacted the oocyte during its development; the follicle is composed of the oocyte and its surrounding follicle cells. The POC is composed of a prominent basement membrane separating the POT from the POF. The reticulin stain clearly defines compartmentation in the ovary and supports redefinition of the POF as the follicle cells that formerly surrounded the oocyte prior to ovulation. J. Morphol. 278:547-562, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Mixed messages: wild female bonobos show high variability in the timing of ovulation in relation to sexual swelling patterns.

PubMed

Douglas, Pamela Heidi; Hohmann, Gottfried; Murtagh, Róisín; Thiessen-Bock, Robyn; Deschner, Tobias

2016-06-30

The evolution of primate sexual swellings and their influence on mating strategies have captivated the interest of biologists for over a century. Across the primate order, variability in the timing of ovulation with respect to females' sexual swelling patterns differs greatly. Since sexual swellings typically function as signals of female fecundity, the temporal relation between ovulation and sexual swellings can impact the ability of males to pinpoint ovulation and thereby affect male mating strategies. Here, we used endocrine parameters to detect ovulation and examined the temporal relation between the maximum swelling phase (MSP) and ovulation in wild female bonobos (Pan paniscus). Data were collected at the Luikotale field site, Democratic Republic of Congo, spanning 36 months. Observational data from 13 females were used to characterise female swelling cycles (N = 70). Furthermore, we measured urinary oestrone and pregnanediol using liquid chromatography-tandem mass spectrometry, and used pregnanediol to determine the timing of ovulation in 34 cycles (N = 9 females). We found that the duration of females' MSP was highly variable, ranging from 1 to 31 days. Timing of ovulation varied considerably in relation to the onset of the MSP, resulting in a very low day-specific probability of ovulation and fecundity across female cycles. Ovulation occurred during the MSP in only 52.9 % of the analysed swelling cycles, and females showed regular sexual swelling patterns in N = 8 swelling cycles where ovulation did not occur. These findings reveal that sexual swellings of bonobos are less reliable indicators of ovulation compared to other species of primates. Female bonobos show unusual variability in the duration of the MSP and in the timing of ovulation relative to the sexual swelling signal. These data are important for understanding the evolution of sexual signals, how they influence male and female mating strategies, and how decoupling visual signals of fecundity from the periovulatory period may affect intersexual conflict. By prolonging the period during which males would need to mate guard females to ascertain paternity, the temporal variability of this signal may constrain mate-guarding efforts by male bonobos.

A verified design of a fault-tolerant clock synchronization circuit: Preliminary investigations

NASA Technical Reports Server (NTRS)

Miner, Paul S.

1992-01-01

Schneider demonstrates that many fault tolerant clock synchronization algorithms can be represented as refinements of a single proven correct paradigm. Shankar provides mechanical proof that Schneider's schema achieves Byzantine fault tolerant clock synchronization provided that 11 constraints are satisfied. Some of the constraints are assumptions about physical properties of the system and cannot be established formally. Proofs are given that the fault tolerant midpoint convergence function satisfies three of the constraints. A hardware design is presented, implementing the fault tolerant midpoint function, which is shown to satisfy the remaining constraints. The synchronization circuit will recover completely from transient faults provided the maximum fault assumption is not violated. The initialization protocol for the circuit also provides a recovery mechanism from total system failure caused by correlated transient faults.

Size of ovulatory follicles in cattle expressing multiple ovulations naturally and its influence on corpus luteum development and fertility.

PubMed

Echternkamp, S E; Cushman, R A; Allan, M F

2009-11-01

Long-term genetic selection of cattle for fraternal twins has increased the frequency of twin and triplet ovulations. In contrast, the ratio of fetal numbers to ovulation sites in pregnant females with twin (0.83) or triplet (0.73) ovulations is <1.0 and the number of calves per parturition is 1.6 and 2.0, respectively. Failure of individual twin or triplet ovulations to yield a conceptus in fertile females indicates a significant contribution of ovulation or oocyte anomalies to increased fertilization failure or early embryonic mortality. The present objective was to identify physiological traits affecting conception in cyclic cattle expressing multiple ovulations naturally, including the effect of ovulation rate on follicle or corpus luteum (CL) size, and their relationship to conception. Diameter of the individual ovulatory follicles was measured by transrectal ultrasonography at AI and ranged from 8 to 30 mm, with a trend for diameter of the individual follicles, and associated CL, to decrease with increasing ovulation rate. Independent of ovulation rate, ovulatory follicles were smaller (P < 0.05) for nulliparous heifers (1.5 yr) compared with parous cows (> or =2.5 yr). Pregnancy and fetal status were diagnosed by transrectal ultrasonography between 42 and 72 d after AI. Fertility was reduced (P < 0.01) for small twin or triplet ovulatory follicles (8 to 8.9 mm vs. 10 to 17.9 mm diam.), whereas fertility in monovular females was reduced (P < 0.01) for large ovulatory follicles (> or =22 vs. 14 to 17.9 mm). Plasma progesterone concentrations increased with ovulation rate and were correlated positively with total CL or ovulatory follicle volume per female, indicating that CL size and function were influenced by the size of the follicle of origin. Progesterone was greater (P < 0.05) in the blood of nulliparous heifers compared with parous cows. The increased proportion of small ovulatory follicles associated with twin and triplet ovulations indicates that some ovulatory follicles were either selected to ovulate at a lesser stage of maturity or rescued while undergoing atresia, thus compromising oocyte competency or ovulation. Of greatest importance for reduced fertility was the greater incidence of pregnancy losses occurring in the middle of gestation in females gestating 2 or more fetuses as an apparent effect of uterine crowding, especially when 2 or more fetuses were contained within 1 uterine horn.

Production, Preservation, and Transfer of South American Camelid Embryos

PubMed Central

Trasorras, Virginia L.; Carretero, María Ignacia; Neild, Deborah M.; Chaves, Maria Graciela; Giuliano, Susana M.; Miragaya, Marcelo H.

2017-01-01

The current review summarizes progress in the field of in vitro and in vivo production of South American Camelid embryos. Both methods require ovarian superstimulation (with FSH and eCG) to obtain multiple ovulations (in vivo embryo production) or to induce follicle growth for oocyte collection (in vitro embryo production). Moreover, superstimulation entails prior administration of hormones that inhibit follicular growth (progesterone, progestagens, and estrogens). Cumulus-oocyte complexes obtained must mature in vivo (buserelin administration) or in vitro to then be subjected to in vitro fertilization or intracytoplasmic sperm injection. All these techniques also require morphologically normal, motile spermatozoa to achieve fertilization. Methods used to decrease semen viscosity and to select the best spermatozoa (Percoll®; Androcoll-ETM) are described. Additionally, nuclear transfer or cloning has been applied in llamas. Up to now, embryo deep-freezing and vitrification have progressed slowly but are at the height of development. Embryos that are obtained by any of these techniques, either in vivo or in vitro, need to be transferred to synchronized recipient females. The best results are achieved after transfer to the left uterine horn with an ipsilateral ovulation. No live offspring have been obtained after the transfer of cryopreserved embryos. Applying reproductive biotechnologies, such as those described, will permit the expansion of genetically selected animals in the population and also that of wild camelid species, vicunas, and guanacos, whose embryos could then be transferred to the uterus of domestic species. PMID:29181380

First live offspring born in superovulated sika deer (Cervus nippon) after embryo vitrification.

PubMed

Wang, L; Zhou, G B; Shi, W Q; Shi, J M; Tian, X Z; Gao, C; Zhang, L; Zhu, S E; Zhang, T T; Zeng, S M; Liu, G S

2012-10-15

The rapid growth in sika deer (Cervus nippon) farming and interest in their conservation is an impetus for development of embryo transfer (ET) procedures. However, a paucity of research has prevented widespread application of ET in this species. The objective of the present study was to establish a multiple ovulation and ET procedure with both fresh and vitrified embryos in sika deer. Multiparous weaned hinds (N = 18) were used as embryo donors during the reproductive season of 2008 at a local breeding farm in China. Estrus was synchronized in donors and recipients (N = 38) by inserting a controlled internal drug release for 12 days (insertion = Day 0). Superovulation was induced with a total of 320 mg of NIH-FSH-P1 (Folltropin-V; Bioniche, Belleville, ON, Canada) given as 40 mg im every 12 h from the afternoon of Day 9 to the morning of Day 13. After estrus was detected, donors were artificially inseminated using a transcervical technique. The embryo recovery rate was 76.8% (63/82), including 1.6% (1/63), 77.8% (49/63), and 1.6% (1/63) blastocysts, morula, and eight-cell embryos, respectively. After transfer of fresh and vitrified embryos, pregnancy rates were 85.7% and 61.6% and birth rates were 64.3% and 53.9% (P > 0.05). In conclusion, we developed a satisfactory multiple ovulation and ET procedure in farmed sika deer using vitrified embryos. Copyright © 2012 Elsevier Inc. All rights reserved.

Safety of a progesterone-releasing intravaginal device as assessed from vaginal mucosal integrity and indicators of systemic inflammation in postpartum dairy cows

PubMed Central

Walsh, Robert B.; LeBlanc, Stephen J.; Vernooy, Erin; Leslie, Kenneth E.

2008-01-01

A clinical trial was conducted to investigate the animal safety of a progesterone-releasing intravaginal device (PRID). Anestrus cows at a mean of 63 ± 3.5 d in milk were randomly assigned to an ovulation-synchronization protocol that included placement of either a PRID or a placebo intravaginal device (PID) or no such treatment. At enrolment and at device removal 7 d later, blood samples were collected. The outcomes of interest included the vaginal reaction to the device, the vaginal mucosal integrity, and the results of bacterial culture of swabs of the vaginal mucosa. In addition, the leukocyte and haptoglobin responses were measured. Although only 5% of the PRID-treated animals compared with 19% of the PID-treated animals had a copious purulent vaginal discharge at the time of device removal, there was no significant difference in the proportions; furthermore, there was no evidence of vaginal mucosal damage associated with either device. The total blood leukocyte count was significantly lower in both the PRID-treated cows and the PID-treated cows after device removal compared with the start of treatment (P < 0.05) and compared with no treatment (P < 0.001); there was no difference in leukocyte response between the 2 device-treated groups. The decrease in leukocyte count was attributed to a significant reduction in the numbers of circulating neutrophils and lymphocytes, a pattern consistent with the luteal phase of the bovine estrus cycle. There was no significant difference in the circulating haptoglobin concentration between the 3 groups of cows. Culture revealed commensal bacterial growth in the vagina of all the cows. PMID:18214161

Accelerated convergence for synchronous approximate agreement

NASA Technical Reports Server (NTRS)

Kearns, J. P.; Park, S. K.; Sjogren, J. A.

1988-01-01

The protocol for synchronous approximate agreement presented by Dolev et. al. exhibits the undesirable property that a faulty processor, by the dissemination of a value arbitrarily far removed from the values held by good processors, may delay the termination of the protocol by an arbitrary amount of time. Such behavior is clearly undesirable in a fault tolerant dynamic system subject to hard real-time constraints. A mechanism is presented by which editing data suspected of being from Byzantine-failed processors can lead to quicker, predictable, convergence to an agreement value. Under specific assumptions about the nature of values transmitted by failed processors relative to those transmitted by good processors, a Monte Carlo simulation is presented whose qualitative results illustrate the trade-off between accelerated convergence and the accuracy of the value agreed upon.

Virtual memory support for distributed computing environments using a shared data object model

NASA Astrophysics Data System (ADS)

Huang, F.; Bacon, J.; Mapp, G.

1995-12-01

Conventional storage management systems provide one interface for accessing memory segments and another for accessing secondary storage objects. This hinders application programming and affects overall system performance due to mandatory data copying and user/kernel boundary crossings, which in the microkernel case may involve context switches. Memory-mapping techniques may be used to provide programmers with a unified view of the storage system. This paper extends such techniques to support a shared data object model for distributed computing environments in which good support for coherence and synchronization is essential. The approach is based on a microkernel, typed memory objects, and integrated coherence control. A microkernel architecture is used to support multiple coherence protocols and the addition of new protocols. Memory objects are typed and applications can choose the most suitable protocols for different types of object to avoid protocol mismatch. Low-level coherence control is integrated with high-level concurrency control so that the number of messages required to maintain memory coherence is reduced and system-wide synchronization is realized without severely impacting the system performance. These features together contribute a novel approach to the support for flexible coherence under application control.

New protocol of clomiphene citrate treatment in women with hypothalamic amenorrhea.

PubMed

Borges, Lavinia Estrela; Morgante, Giuseppe; Musacchio, Maria Concetta; Petraglia, Felice; De Leo, Vincenzo

2007-06-01

To determine if a new protocol of administration of clomiphene citrate (CC) is effective in menstrual cycle recovery in women with hypothalamic secondary amenorrhea. This was an open-label study. Patients comprised a group of eight women with secondary amenorrhea. Interventions. An oral preparation containing CC (50 mg/day) was administered for 5 days followed by a double dose (100 mg/day) for another 5 days, initiated on day 3 after estrogen/progestogen-induced withdrawal bleeding. If ovulation and vaginal bleeding occurred, treatment continued in the two next months with 100 mg/day from day 3 to day 7 day of the cycle. Cycle control was evaluated at each visit, when patients recorded bleeding patterns and tablet intake. Data on the intensity and duration of bleeding were collected. Six patients responded to the first cycle of CC administration, resuming normal menstrual cycles. The other two patients failed to menstruate after the first 10 days of treatment with CC and repeated the same protocol. After the second administration, these two women also had normal menstrual bleeding. The present data show that this new protocol of CC treatment may be useful to restore normal menstrual cycles in young women with hypothalamic amenorrhea.

Reproductive Medicine in Amphibians.

PubMed

Chai, Norin

2017-05-01

Reproduction of amphibians includes ovulation, spermiation, fertilization, oviposition, larval stage and development, and metamorphosis. A problem at any stage could lead to reproductive failure. To stimulate reproduction, environmental conditions must be arranged to simulate changes in natural habits. Reproductive life history is well documented in amphibians; a thorough knowledge of this subject will aid the practitioner in diagnosis and treatment. Technologies for artificial reproduction are developing rapidly, and some protocols may be transferable to privately kept or endangered species. Reproductive tract disorders are rarely described; no bacterial or viral diseases are known that specifically target the amphibian reproductive system. Copyright © 2016 Elsevier Inc. All rights reserved.

Effect of Aegle marmelos and Murraya koenigii in treatment of delayed pubertal buffaloes heifers

PubMed Central

Baitule, Mohan M.; Gawande, A. P.; Kumar, Umesh; Sahatpure, S. K.; Patil, Manoj S.; Baitule, Mansi M.

2016-01-01

Aim: This study aims to study the estrus induction, ovulation, and conception rate of delayed puberty in buffaloes heifers by feeding a herbal plants Aegle marmelos (bael/bili/bhel leaf) and Murraya koenigii (Curry leaf). Materials and Methods: Totally, 24 buffalo heifers with delayed puberty were selected for the present study and divided randomly in four equal groups (n=6). Before experiment, all animals were dewormed with albendazole at 10 mg/kg body weight to prevent them from the stress of parasitism. In the present experiment, four group taken and Group I (n=6) treated with A. marmelos, Group II (n=6) treated with M. koenigii, Group III (n=6) treated with mixture of A. marmelos and M. koenigii and fed for 9 days. Group IV (n=6) considered as control and fed with concentrate only. The blood samples were collected from all the animals on day 0 (before treatment), 4, 9 (during treatment), on the day of estrus and day 8 after the onset of estrus. The 10 ml blood was collected from the jugular vein of all the experimental animals for estimation of serum calcium, inorganic phosphorus, and progesterone (P4). The estrus response, ovulation, conception rate along with serum calcium, inorganic phosphorus, and progesterone level were determined by the standard protocol. Results: From Group III 4 heifers, from Group II 3 heifers, and from Group I and IV (Control) 2 heifers each, exhibited the estrus. The estrus response was recorded as 33.33%, 50.00%, 75.00%, and 33.33% in Group I, Group II, Group III, and Group IV, respectively. In treatment Group III, serum calcium found significantly more (p<0.05) on day 8 post-estrus as compared to other groups at a similar interval. Inorganic phosphorus and progesterone show no significant difference between groups. The ovulation and conception rates are comparatively better in Group III (75%) buffalo heifers than other groups. Conclusion: Herbal supplementation of A. marmelos and M. koenigii in combination, as well as M. koenigii alone, were found effective in fertility improvement in delayed pubertal buffalo heifers by increasing ovulation and conception rate. PMID:28096608

Intravenous infusion of PAF affects ovulation, fertilization and preimplantation embryonic development in NZB x NZW F1 hybrid mice.

PubMed

Sakellariou, Maria; Drakakis, Peter; Antonopoulou, Smaragdi; Anagnostou, Elli; Loutradis, Dimitris; Patargias, Theoxaris

2008-03-01

Platelet Activating Factor (PAF) is a bioactive phospholipid, which exhibits a variety of biological activities and plays a significant role in all aspects of reproduction. In this work, a single intravenous injection of various concentrations of PAF shortly after Human Chorionic Gonadotropin (HCG) administration as well as 24 and 48 h before HCG administration was studied in NZB x NZW F1 hybrid mice. Optimum results were observed when PAF was injected just after the administration of HCG. In this protocol, the concentrations of PAF exhibited bell-shaped response to every stage of development. Any concentration of PAF between 5.5 x 10(-11) and 5.5 x 10(-15)g/g b.w., caused an improved ovulation rate, an increased fertilization rate, an increased rate of cell cycle and an enhanced hatching blastocyst rate (P<0.05 for all stages). Injection of lyso-PAF had no effect in any stage. Our data show that the effect of PAF on early stages of embryo development in vitro is dependent on its way of administration, on the concentrations used as well as on the time PAF is injected.

Evaluation of the acceptability of intravaginal prasterone ovule administration using an applicator.

PubMed

Montesino, Marlene; Labrie, Fernand; Archer, David F; Zerhouni, Jaâfar; Côté, Isabelle; Lavoie, Lyne; Beauregard, Adam; Martel, Céline; Vaillancourt, Mario; Moyneur, Erick; Balser, John

2016-01-01

The objective of the study is to evaluate the acceptability of the intravaginal administration of ovules/suppositories of DHEA (dehydroepiandrosterone, prasterone) for the treatment of vulvovaginal atrophy (VVA) in women with moderate to severe dyspareunia who were administered daily for 12 weeks intravaginal 0.50% (6.5 mg) DHEA or placebo. There were a total of 373 women in the per-protocol population who responded to the questionnaire for both treatment groups. While it was planned that the applicator would be evaluated as suitable if at least 80% of participants have a global score  ≤ 2 units, 99% and 100% of participants had a score  ≤ 2 units in the placebo and DHEA groups, respectively, for the global score (mean of 5 questions). When asked about like and dislike the technique of drug administration, 284 comments were positive, while 114 women gave no comment. About 92-94% of women indicated that they were very confident to be able use the applicator successfully in the future. The survey shows a high degree of satisfaction and of confidence to use the applicator successfully in the future.

Conceptus development and transcriptome at preimplantation stages in lactating dairy cows of distinct genetic groups and estrous cyclic statuses.

PubMed

Ribeiro, E S; Monteiro, A P A; Bisinotto, R S; Lima, F S; Greco, L F; Ealy, A D; Thatcher, W W; Santos, J E P

2016-06-01

The objectives were to compare development and transcriptome of preimplantation conceptuses 15 d after synchronized ovulation and artificial insemination (AI) according to the genetic background of the cow and estrous cyclicity at the initiation of the synchronization program. On d 39±3 postpartum, Holstein cows that were anovular (HA; n=10), Holstein cows that were estrous cyclic (HC; n=25), and Jersey/Holstein crossbred cows that were estrous cyclic (CC; n=25) were randomly selected in a grazing herd and subjected to the Ovsynch protocol. All cows were inseminated on d 49±3 postpartum, which was considered study d 0. Blood was sampled and analyzed for concentrations of progesterone, estradiol, insulin, and insulin-like growth factor 1 (IGF-1) on study d -10, -3, -1, 7, and 15 relative to AI. On study d 15, uteri were flushed and recovered fluid had IFN-τ concentrations measured and subjected to metabolomic analysis. Morphology of the recovered conceptuses was evaluated, and mRNA was extracted and subjected to transcriptome microarray analysis. Compared with HC, CC presented greater concentrations of progesterone and estradiol in plasma, with corpora lutea and preovulatory follicles of similar size. Conceptuses from CC were larger, tended to secrete greater amounts of IFN-τ, and had greater transcript expression of peroxisome proliferator-activated receptor gamma (PPARγ), an important transcription factor that coordinates lipid metabolism and elongation at preimplantation development. In addition, pregnant CC had greater concentrations of anandamide in the uterine flush, which might be important for elongation of the conceptus and early implantation. Conceptuses from HA were also longer and secreted greater amounts of IFN-τ than conceptuses from HC, likely because of the distinct progesterone profiles before and after AI. Nonetheless, anovular cows had reduced concentrations of IGF-1 in plasma, and their conceptuses presented remarkable transcriptomic differences. Some of the altered transcripts suggest that conceptus cells from anovular cows might be under greater cellular stress and presented markers suggesting increased apoptosis and autophagy, which could lead to increased mortality after d 15 of development. Estrous cyclicity had more impact on transcriptome of bovine conceptus than genetic background, and the developmental changes observed during the preimplantation period might be linked to differences in fertility among groups. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Robust outer synchronization between two nonlinear complex networks with parametric disturbances and mixed time-varying delays

NASA Astrophysics Data System (ADS)

Zhang, Chuan; Wang, Xingyuan; Luo, Chao; Li, Junqiu; Wang, Chunpeng

2018-03-01

In this paper, we focus on the robust outer synchronization problem between two nonlinear complex networks with parametric disturbances and mixed time-varying delays. Firstly, a general complex network model is proposed. Besides the nonlinear couplings, the network model in this paper can possess parametric disturbances, internal time-varying delay, discrete time-varying delay and distributed time-varying delay. Then, according to the robust control strategy, linear matrix inequality and Lyapunov stability theory, several outer synchronization protocols are strictly derived. Simple linear matrix controllers are designed to driver the response network synchronize to the drive network. Additionally, our results can be applied on the complex networks without parametric disturbances. Finally, by utilizing the delayed Lorenz chaotic system as the dynamics of all nodes, simulation examples are given to demonstrate the effectiveness of our theoretical results.

Sporophytic ovule tissues modulate the initiation and progression of apomixis in Hieracium.

PubMed

Tucker, Matthew R; Okada, Takashi; Johnson, Susan D; Takaiwa, Fumio; Koltunow, Anna M G

2012-05-01

Apomixis in Hieracium subgenus Pilosella initiates in ovules when sporophytic cells termed aposporous initial (AI) cells enlarge near sexual cells undergoing meiosis. AI cells displace the sexual structures and divide by mitosis to form unreduced embryo sac(s) without meiosis (apomeiosis) that initiate fertilization-independent embryo and endosperm development. In some Hieracium subgenus Pilosella species, these events are controlled by the dominant LOSS OF APOMEIOSIS (LOA) and LOSS OF PARTHENOGENESIS (LOP) loci. In H. praealtum and H. piloselloides, which both contain the same core LOA locus, the timing and frequency of AI cell formation is altered in derived mutants exhibiting abnormal funiculus growth and in transgenic plants expressing rolB which alters cellular sensitivity to auxin. The impact on apomictic and sexual reproduction was examined here when a chimeric RNAse gene was targeted to the funiculus and basal portions of the ovule, and also when polar auxin transport was inhibited during ovule development following N-1-naphthylphthalamic acid (NPA) application. Both treatments led to ovule deformity in the funiculus and distal parts of the ovule and LOA-dependent alterations in the timing, position, and frequency of AI cell formation. In the case of NPA treatment, this correlated with increased expression of DR5:GFP in the ovule, which marks the accumulation of the plant hormone auxin. Our results show that sporophytic information potentiated by funiculus growth and polar auxin transport influences ovule development, the initiation of apomixis, and the progression of embryo sac development in Hieracium. Signals associated with ovule pattern formation and auxin distribution or perception may influence the capacity of sporophytic ovule cells to respond to LOA.

Seminal Plasma Induces Ovulation in Llamas in the Absence of a Copulatory Stimulus: Role of Nerve Growth Factor as an Ovulation-Inducing Factor

PubMed Central

Berland, Marco A.; Ulloa-Leal, Cesar; Barría, Miguel; Wright, Hollis; Dissen, Gregory A.; Silva, Mauricio E.; Ojeda, Sergio R.

2016-01-01

Llamas are considered to be reflex ovulators. However, semen from these animals is reported to be rich in ovulation-inducing factor(s), one of which has been identified as nerve growth factor (NGF). These findings suggest that ovulation in llamas may be elicited by chemical signals contained in semen instead of being mediated by neural signals. The present study examines this notion. Llamas displaying a preovulatory follicle were assigned to four groups: group 1 received an intrauterine infusion (IUI) of PBS; group 2 received an IUI of seminal plasma; group 3 was mated to a male whose urethra had been surgically diverted (urethrostomized male); and group 4 was mated to an intact male. Ovulation (detected by ultrasonography) occurred only in llamas mated to an intact male or given an IUI of seminal plasma and was preceded by a surge in plasma LH levels initiated within an hour after coitus or IUI. In both ovulatory groups, circulating β-NGF levels increased within 15 minutes after treatment, reaching values that were greater and more sustained in llamas mated with an intact male. These results demonstrate that llamas can be induced to ovulate by seminal plasma in the absence of copulation and that copulation alone cannot elicit ovulation in the absence of seminal plasma. In addition, our results implicate β-NGF as an important mediator of seminal plasma-induced ovulation in llamas because ovulation does not occur if β-NGF levels do not increase in the bloodstream, a change that occurs promptly after copulation with an intact male or IUI of seminal plasma. PMID:27355492

Extended-release metformin does not reduce the clomiphene citrate dose required to induce ovulation in polycystic ovary syndrome.

PubMed

Cataldo, Nicholas A; Barnhart, Huiman X; Legro, Richard S; Myers, Evan R; Schlaff, William D; Carr, Bruce R; Diamond, Michael P; Carson, Sandra A; Steinkampf, Michael P; Coutifaris, Christos; McGovern, Peter G; Gosman, Gabriella; Nestler, John E; Giudice, Linda C

2008-08-01

When used for ovulation induction, higher doses of clomiphene may lead to antiestrogenic side effects that reduce fecundity. It has been suggested that metformin in combination with clomiphene can restore ovulation to some clomiphene-resistant anovulators with polycystic ovary syndrome (PCOS). Our objective was to determine if cotreatment with extended-release metformin (metformin XR) can lower the threshold dose of clomiphene needed to induce ovulation in women with PCOS. A secondary analysis of data from the National Institute of Child Health and Human Development Cooperative Multicenter Reproductive Medicine Network prospective, double-blind, placebo-controlled multicenter clinical trial, Pregnancy in Polycystic Ovary Syndrome, was performed. Study volunteers at multiple academic medical centers were included. Women with PCOS and elevated serum testosterone who were randomized to clomiphene alone or with metformin (n = 209 in each group) were included in the study. Clomiphene citrate, 50 mg daily for 5 d, was increased to 100 and 150 mg in subsequent cycles if ovulation was not achieved; half also received metformin XR, 1000 mg twice daily. Treatment was for up to 30 wk or six cycles, or until first pregnancy. Ovulation was confirmed by a serum progesterone more than or equal to 5 ng/ml, drawn prospectively every 1-2 wk. The overall prevalence of at least one ovulation after clomiphene was 75 and 83% (P = 0.04) for the clomiphene-only and clomiphene plus metformin groups, respectively. Using available data from 314 ovulators, the frequency distribution of the lowest clomiphene dose (50, 100, or 150 mg daily) resulting in ovulation was indistinguishable between the two treatment groups. Metformin XR does not reduce the lowest dose of clomiphene that induces ovulation in women with PCOS.

Effects of varying doses of β-nerve growth factor on the timing of ovulation, plasma progesterone concentration and corpus luteum size in female alpacas (Vicugna pacos).

PubMed

Stuart, C C; Vaughan, J L; Kershaw-Young, C M; Wilkinson, J; Bathgate, R; de Graaf, S P

2015-11-01

Ovulation in camelids is induced by the seminal plasma protein ovulation-inducing factor (OIF), recently identified as β-nerve growth factor (β-NGF). The present study measured the total protein concentration in alpaca seminal plasma using a bicinchoninic acid (BCA) protein quantification assay and found it to be 22.2±2.0mgmL(-1). To measure the effects of varying doses of β-NGF on the incidence and timing of ovulation, corpus luteum (CL) size and plasma progesterone concentration, 24 female alpacas were synchronised and treated with either: (1) 1mL 0.9% saline (n=5); (2) 4µg buserelin (n=5); (3) 1mg β-NGF protein (n=5); (4) 0.1mg β-NGF (n=5); or (5) 0.01mg β-NGF (n=4). Females were examined by transrectal ultrasonography at 1-2-h intervals between 20 and 45h after treatment or until ovulation occurred, as well as on Day 8 to observe the size of the CL, at which time blood was collected to measure plasma progesterone concentrations. Ovulation was detected in 0/5, 5/5, 5/5, 3/5 and 0/4 female alpacas treated with saline, buserelin, 1, 0.1 and 0.01mg β-NGF, respectively. Mean ovulation interval (P=0.76), CL diameter (P=0.96) and plasma progesterone concentration (P=0.96) did not differ between treatments. Mean ovulation interval overall was 26.2±1.0h. In conclusion, buserelin and 1mg β-NGF are equally effective at inducing ovulation in female alpacas, but at doses ≤0.1mg, β-NGF is not a reliable method for the induction of ovulation.

Seminal Plasma Induces Ovulation in Llamas in the Absence of a Copulatory Stimulus: Role of Nerve Growth Factor as an Ovulation-Inducing Factor.

PubMed

Berland, Marco A; Ulloa-Leal, Cesar; Barría, Miguel; Wright, Hollis; Dissen, Gregory A; Silva, Mauricio E; Ojeda, Sergio R; Ratto, Marcelo H

2016-08-01

Llamas are considered to be reflex ovulators. However, semen from these animals is reported to be rich in ovulation-inducing factor(s), one of which has been identified as nerve growth factor (NGF). These findings suggest that ovulation in llamas may be elicited by chemical signals contained in semen instead of being mediated by neural signals. The present study examines this notion. Llamas displaying a preovulatory follicle were assigned to four groups: group 1 received an intrauterine infusion (IUI) of PBS; group 2 received an IUI of seminal plasma; group 3 was mated to a male whose urethra had been surgically diverted (urethrostomized male); and group 4 was mated to an intact male. Ovulation (detected by ultrasonography) occurred only in llamas mated to an intact male or given an IUI of seminal plasma and was preceded by a surge in plasma LH levels initiated within an hour after coitus or IUI. In both ovulatory groups, circulating β-NGF levels increased within 15 minutes after treatment, reaching values that were greater and more sustained in llamas mated with an intact male. These results demonstrate that llamas can be induced to ovulate by seminal plasma in the absence of copulation and that copulation alone cannot elicit ovulation in the absence of seminal plasma. In addition, our results implicate β-NGF as an important mediator of seminal plasma-induced ovulation in llamas because ovulation does not occur if β-NGF levels do not increase in the bloodstream, a change that occurs promptly after copulation with an intact male or IUI of seminal plasma.

Sporophytic ovule tissues modulate the initiation and progression of apomixis in Hieracium

PubMed Central

Tucker, Matthew R.; Okada, Takashi; Johnson, Susan D.; Takaiwa, Fumio; Koltunow, Anna M. G.

2012-01-01

Apomixis in Hieracium subgenus Pilosella initiates in ovules when sporophytic cells termed aposporous initial (AI) cells enlarge near sexual cells undergoing meiosis. AI cells displace the sexual structures and divide by mitosis to form unreduced embryo sac(s) without meiosis (apomeiosis) that initiate fertilization-independent embryo and endosperm development. In some Hieracium subgenus Pilosella species, these events are controlled by the dominant LOSS OF APOMEIOSIS (LOA) and LOSS OF PARTHENOGENESIS (LOP) loci. In H. praealtum and H. piloselloides, which both contain the same core LOA locus, the timing and frequency of AI cell formation is altered in derived mutants exhibiting abnormal funiculus growth and in transgenic plants expressing rolB which alters cellular sensitivity to auxin. The impact on apomictic and sexual reproduction was examined here when a chimeric RNAse gene was targeted to the funiculus and basal portions of the ovule, and also when polar auxin transport was inhibited during ovule development following N-1-naphthylphthalamic acid (NPA) application. Both treatments led to ovule deformity in the funiculus and distal parts of the ovule and LOA-dependent alterations in the timing, position, and frequency of AI cell formation. In the case of NPA treatment, this correlated with increased expression of DR5:GFP in the ovule, which marks the accumulation of the plant hormone auxin. Our results show that sporophytic information potentiated by funiculus growth and polar auxin transport influences ovule development, the initiation of apomixis, and the progression of embryo sac development in Hieracium. Signals associated with ovule pattern formation and auxin distribution or perception may influence the capacity of sporophytic ovule cells to respond to LOA. PMID:22378948

Reproductive performance of seasonally anovular mixed-bred dairy goats induced to ovulate with a combination of progesterone and eCG or estradiol.

PubMed

Contreras-Villarreal, Viridiana; Meza-Herrera, César A; Rivas-Muñoz, Raymundo; Angel-Garcia, Oscar; Luna-Orozco, Juan R; Carrillo, Evaristo; Mellado, Miguel; Véliz-Deras, Francisco G

2016-06-01

Adult goats (n = 32) were randomly assigned to one of four treatments (n = 8, each): (i) progesterone (P4 ) + equine chorionic gonadotropin (eCG), treated with 25 mg progesterone intramuscularly (i.m.) + 250 IU eCG 24 h later; (ii) cronolone + eCG, treated with vaginal sponges - 20 mg cronolone × 7 days + 250 IU eCG at pessary removal; (ii) P4 + estradiol (E2 ), treated with 25 mg progesterone i.m. + 1 mg estradiol 24 h later; (iv) cronolone + E2 , treated with vaginal sponges - 20 mg cronolone × 7 days + 1 mg of estradiol i.m. at pessary removal. Goats were tested for estrus throughout the presence of a buck. Seven days prior and after treatment, an ovarian ultrasonographic scanning was performed to determine ovarian function and structures. An ultrasonographic pregnancy diagnosis was performed on day 30 post-service. In all groups, 100% estrus response was observed within 96 h post-treatment. While ovulation occurred in 100% of P4 + eCG and cronolone + eCG treated goats, the other groups only depicted 50% ovulatory activity (P < 0.05). Pregnancy rate was higher (P <0.05) in the P4 + eCG and cronolone + eCG groups (88 and 100%, respectively), compared with 38% in P4 + E2 and cronolone + E2 groups. The best treatments were those in which eCG was applied. The P4 + eCG treatment was a pessary-free, cheaper and effective protocol to induce ovulation in goats during the seasonal anovulatory period. © 2015 Japanese Society of Animal Science.

Effectiveness of electroacupuncture for polycystic ovary syndrome: study protocol for a randomized controlled trial.

PubMed

Chen, Jiao; Feng, Shuwei; Zeng, Jiuzhi; Wu, Xi; Yang, Mingxiao; Tang, Hongzhi; Fan, Huaying; Yang, Jie; Liang, Fanrong

2016-05-21

Whether electroacupuncture is effective for patients with polycystic ovary syndrome is still inconclusive. Therefore, this study aims to evaluate the add-on effects of electroacupuncture to conventional drugs for the treatment of polycystic ovary syndrome. This study is a two-center, open-labeled, randomized, controlled trial. A total of 116 eligible patients with polycystic ovary syndrome will be randomly allocated in a 1:1 ratio to the electroacupuncture plus clomiphene citrate group or to the clomiphene citrate group. Participants in the electroacupuncture plus clomiphene citrate group will receive electroacupuncture treatment in addition to clomiphene citrate capsules, whereas participants in the clomiphene citrate group will be prescribed clomiphene citrate capsules only. Electroacupuncture treatment will be performed from the fifth day of menstruation or withdrawal bleeding until the next menstruation, in three sessions per week for three menstrual cycles. The primary outcome is the ovulation rate. The secondary outcomes include the dominant follicle rate, mean number of dominant follicles, endometrial thickness, time point of ovulation, follicular size before ovulation, luteinizing hormone, estradiol level, and pregnancy rate. The measuring points for outcomes will be baseline and the completion of treatment. Any adverse events occurring during the trial process will be recorded. In addition, a quality-monitoring group independent from the research team will be set up to control the quality of the trial. The design and methodological rigor of this trial will allow for the collection of valuable data to evaluate the effectiveness of electroacupuncture for treating polycystic ovary syndrome. Therefore, this trial will contribute reliable evidence for use in clinical decision-making in acupuncture therapy of polycystic ovary syndrome as well as to future research in acupuncture for polycystic ovary syndrome. Chinese Clinical Trial Registry, ChiCTR-IOR-15007358 , registered on 26 October 2015.

Use of equine chorionic gonadotropin to control reproduction of the dairy cow: a review.

PubMed

De Rensis, F; López-Gatius, F

2014-04-01

Equine chorionic gonadotropin (eCG) is a member of the glycoprotein family of hormones along with LH, FSH and thyroid-stimulating hormone. In non-equid species, eCG shows high LH- and FSH-like activities and has a high affinity for both FSH and LH receptors in the ovaries. On the granulosa and thecal cells of the follicle, eCG has long-lasting LH- and FSH-like effects that stimulate oestradiol and progesterone secretion. Thus, eCG administration in dairy cattle results in fewer atretic follicles, the recruitment of more small follicles showing an elevated growth rate, the sustained growth of medium and large follicles and improved development of the dominant and pre-ovulatory follicle. In consequence, the quality of the ensuing CL is improved, and thereby progesterone secretion increased. Based on these characteristics, eCG treatment is utilized in veterinary medicine to control the reproductive activity of the cow by i) improving reproductive performance during early post-partum stages; ii) increasing ovulation and pregnancy rates in non-cyclic cows; iii) improving the conception rate in cows showing delayed ovulation; and finally, iv) eCG is currently included in protocols for fixed-time artificial insemination since after inducing the synchrony of ovulation using a progesterone-releasing device, eCG has beneficial effects on embryo development and survival. The above effects are not always observed in cyclic animals, but they are evident in animals in which LH secretion and ovarian activity are reduced or compromised, for instance, during the early post-partum period, under seasonal heat stress, in anoestrus animals or in animals with a low body condition score. © 2014 Blackwell Verlag GmbH.

Permutation parity machines for neural cryptography.

PubMed

Reyes, Oscar Mauricio; Zimmermann, Karl-Heinz

2010-06-01

Recently, synchronization was proved for permutation parity machines, multilayer feed-forward neural networks proposed as a binary variant of the tree parity machines. This ability was already used in the case of tree parity machines to introduce a key-exchange protocol. In this paper, a protocol based on permutation parity machines is proposed and its performance against common attacks (simple, geometric, majority and genetic) is studied.

Permutation parity machines for neural cryptography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reyes, Oscar Mauricio; Escuela de Ingenieria Electrica, Electronica y Telecomunicaciones, Universidad Industrial de Santander, Bucaramanga; Zimmermann, Karl-Heinz

2010-06-15

Recently, synchronization was proved for permutation parity machines, multilayer feed-forward neural networks proposed as a binary variant of the tree parity machines. This ability was already used in the case of tree parity machines to introduce a key-exchange protocol. In this paper, a protocol based on permutation parity machines is proposed and its performance against common attacks (simple, geometric, majority and genetic) is studied.

Ovule positions within linear fruit are correlated with nonrandom mating in Robinia pseudoacacia

PubMed Central

Yuan, Cunquan; Sun, Yuhan; Sun, Peng; Li, Yunfei; Hu, Ruiyang; Zhao, Keqi; Wang, Jinxing; Li, Yun

2016-01-01

Post-pollination processes can lead to nonrandom mating among compatible pollen donors. Moreover, morphological patterns of ovule development within linear fruits are reportedly nonrandom and depend on ovule position. However, little is known about the relationship between nonrandom mating and ovule position within linear fruit. Here, we combined controlled pollen competition experiments and paternity analyses on R. pseudoacacia to better understand nonrandom mating and its connection with ovule position. Molecular determination of siring success showed a significant departure from the expected ratio based on each kind of pollen mixture, suggesting a nonrandom mating. Outcrossed pollen grains, which were strongly favored, produced significantly more progeny than other pollen grains. Paternity analyses further revealed that the distribution of offspring produced by one specific pollen source was also nonrandom within linear fruit. The stylar end, which has a higher probability of maturation, produced a significantly higher number of outcrossed offspring than other offspring, suggesting a correlation between pollen source and ovule position. Our results suggested that a superior ovule position exists within the linear fruit in R. pseudoacacia, and the pollen that was strongly favored often preferentially occupies the ovules that were situated in a superior position, which ensured siring success and facilitated nonrandom mating. PMID:27819357

Files synchronization from a large number of insertions and deletions

NASA Astrophysics Data System (ADS)

Ellappan, Vijayan; Kumari, Savera

2017-11-01

Synchronization between different versions of files is becoming a major issue that most of the applications are facing. To make the applications more efficient a economical algorithm is developed from the previously used algorithm of “File Loading Algorithm”. I am extending this algorithm in three ways: First, dealing with non-binary files, Second backup is generated for uploaded files and lastly each files are synchronized with insertions and deletions. User can reconstruct file from the former file with minimizing the error and also provides interactive communication by eliminating the frequency without any disturbance. The drawback of previous system is overcome by using synchronization, in which multiple copies of each file/record is created and stored in backup database and is efficiently restored in case of any unwanted deletion or loss of data. That is, to introduce a protocol that user B may use to reconstruct file X from file Y with suitably low probability of error. Synchronization algorithms find numerous areas of use, including data storage, file sharing, source code control systems, and cloud applications. For example, cloud storage services such as Drop box synchronize between local copies and cloud backups each time users make changes to local versions. Similarly, synchronization tools are necessary in mobile devices. Specialized synchronization algorithms are used for video and sound editing. Synchronization tools are also capable of performing data duplication.

Use of letrozole and clomiphene citrate combined with gonadotropins in clomiphene-resistant infertile women with polycystic ovary syndrome: a prospective study

PubMed Central

Xi, Wenyan; Liu, Shankun; Mao, Hui; Yang, Yongkang; Xue, Xiang; Lu, Xiaoning

2015-01-01

Background Gonadotropin has been used to stimulate ovulation in clomiphene-resistant infertile women with polycystic ovary syndrome (PCOS), but it is associated with overstimulated cycles with the development of many follicles. The aim of the study was to evaluate the effectiveness and efficacy of letrozole and clomiphene citrate (CC) combined with human menopausal gonadotropin (HMG) in CC-resistant infertile women with PCOS. Methods Ninety-four women received the letrozole + HMG, 90 women received CC + HMG, and 71 women received HMG only. All women received one treatment regimen in one treatment cycle. All patients were given HMG 75 IU on alternate days daily starting on day 3 or day 7 until the day of administration of human chorionic gonadotropin. Results The rate of monofollicular development was 80.2% in the letrozole + HMG group, 65.3% in the CC + HMG group, and 54.7% in the HMG-only group (P<0.05 for letrozole + HMG vs the other two groups). The number of developing follicles (≥14 mm follicles) and the cycle cancellation rate due to ovarian hyperresponse were the lowest in the letrozole + HMG group, but the difference was not significant. The ovulation and pregnancy rate were similar among the three protocols. The HMG dose needed and the mean duration of treatment were significantly lower in the letrozole + HMG and CC + HMG groups compared with the HMG-only group. Conclusion Letrozole in combination with HMG is an effective protocol for reducing the risks of hyperstimulation for ovarian induction in CC-resistant women with PCOS. This combination may be more appropriate in patients who are particularly sensitive to gonadotropin. PMID:26648691

Use of letrozole and clomiphene citrate combined with gonadotropins in clomiphene-resistant infertile women with polycystic ovary syndrome: a prospective study.

PubMed

Xi, Wenyan; Liu, Shankun; Mao, Hui; Yang, Yongkang; Xue, Xiang; Lu, Xiaoning

2015-01-01

Gonadotropin has been used to stimulate ovulation in clomiphene-resistant infertile women with polycystic ovary syndrome (PCOS), but it is associated with overstimulated cycles with the development of many follicles. The aim of the study was to evaluate the effectiveness and efficacy of letrozole and clomiphene citrate (CC) combined with human menopausal gonadotropin (HMG) in CC-resistant infertile women with PCOS. Ninety-four women received the letrozole + HMG, 90 women received CC + HMG, and 71 women received HMG only. All women received one treatment regimen in one treatment cycle. All patients were given HMG 75 IU on alternate days daily starting on day 3 or day 7 until the day of administration of human chorionic gonadotropin. The rate of monofollicular development was 80.2% in the letrozole + HMG group, 65.3% in the CC + HMG group, and 54.7% in the HMG-only group (P<0.05 for letrozole + HMG vs the other two groups). The number of developing follicles (≥14 mm follicles) and the cycle cancellation rate due to ovarian hyperresponse were the lowest in the letrozole + HMG group, but the difference was not significant. The ovulation and pregnancy rate were similar among the three protocols. The HMG dose needed and the mean duration of treatment were significantly lower in the letrozole + HMG and CC + HMG groups compared with the HMG-only group. Letrozole in combination with HMG is an effective protocol for reducing the risks of hyperstimulation for ovarian induction in CC-resistant women with PCOS. This combination may be more appropriate in patients who are particularly sensitive to gonadotropin.

Effects of Letrozole-HMG and Clomiphene-HMG on Incidence of Luteinized Unruptured Follicle Syndrome in Infertile Women Undergoing Induction Ovulation and Intrauterine Insemination: A Randomised Trial.

PubMed

Azmoodeh, Azra; Pejman Manesh, Mansoureh; Akbari Asbagh, Firouzeh; Ghaseminejad, Azizeh; Hamzehgardeshi, Zeinab

2015-09-01

Luteinized unruptured follicle (LUF) syndrome is considered a cause of ovulation failure and a subtle cause of infertility. Preovulatory injection of human chorionic gonadotropin (HCG) prevents or treats LUF syndrome, but it has also occurred after the induction of ovulation with clomiphene/HMG and HCG. This study was designed for evaluation and comparison of LUF incidence in eligible infertile women undergoing two stimulation protocols (clomiphene + HMG and letrozole + HMG) in addition to intrauterine insemination (IUI). Some related factors were compared between LUF and non-LUF cycles as secondary outcomes. The study was designed as a prospective randomized controlled trial. Patients were randomized using a table of random numbers into two equal protocol groups. For group A, (n = 90) clomiphene citrate was administrated orally in doses of 100 mg/day, and group B (n = 90) orally received letrozole 5 mg/day from day 3 to 7 of the menstrual cycle. Then HMG 75IU/day was administered intramuscularly in both groups on day 8 of the menstrual cycle and the dose was adjusted on the basis of ovarian response. The optimum size of preovulatory follicles for the injection of HCG (10,000 IU) was considered 18-23 mm. The number and size of preovulatory follicles were assessed by vaginal ultrasound 12 h before HCG (D0). Endometrial thickness was measured as well. IUI was performed on all patients 38-40 h after HCG. The second ultrasound examination was performed to observe the evidence of oocyte releasing at the time of IUI (D1). If the follicles were unruptured, a third sonography was performed on day 7 after HCG (D7) to observe LUF syndrome. There was a significant difference between clomiphene-HMG and letrozole-HMG in LUF (p = 0.021) and pregnancy (p = 0.041). The complete LUF in letrozole-HMG was lower than the alternative group and the pregnancy rate was higher. The patients in the non-LUF group had higher midluteal progesterone and a thicker endometrium compared to LUF cycles (p = 0.039) and (p < 0.001). The results of our multivariate logistic regression indicate that size 18-19.9 mm leads to the complete LUF  less than ≥22 mm [AOR: 0.25, P = 0.005], and  in size 20- 21.9 mm  as well [AOR: 0.17, P = 0.002]. Letrozole, with lower incidences of LUF, is more effective than clomiphene citrate for the induction of ovulation in IUI cycles. In our study, we illustrated that larger follicles of ≥22 mm diameter were associated with higher incidences of LUF. We recommend that further studies investigate and focus on the relationship between follicular size and/or full hormonal profiles and LUF.

Analysis of OPACITY and PLAID Protocols for Contactless Smart Cards

DTIC Science & Technology

2012-09-01

9 3. Access Control ........................................................................ 9 E . THREATS AND...Synchronization .............................. 23 c. Simple Integration and Interoperability ..................... 24 E . MODES OF OPERATION...Interoperability ..................... 47 E . MODES OF OPERATIONS ................................................................ 47 F. SUGGESTED KEY

Progestogen treatments for cycle management in a sheep model of assisted conception affect the growth patterns, the expression of luteinizing hormone receptors, and the progesterone secretion of induced corpora lutea.

PubMed

Letelier, Claudia; García-Fernández, Rosa Ana; Contreras-Solis, Ignacio; Sanchez, María Angeles; Garcia-Palencia, Pilar; Sanchez, Belen; Gonzalez-Bulnes, Antonio; Flores, Juana María

2010-03-01

To determine, in a sheep model, the effect of a short-term progestative treatment on growth dynamics and functionality of induced corpora lutea. Observational, model study. Public university. Sixty adult female sheep. Synchronization and induction of ovulation with progestogens and prostaglandin analogues; ovarian ultrasonography, blood sampling, and ovariectomy. Determination of pituitary function and morphologic characteristics, expression of luteinizing hormone (LH) receptors, and progesterone secretion of corpora lutea. The use of progestative pretreatments for assisted conception affect the growth patterns, the expression of LH receptors, and the progesterone secretion of induced corpora lutea. The current study indicates, in a sheep model, the existence of deleterious effects from progestogens on functionality of induced corpora lutea. Copyright 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Bidirectional private key exchange using delay-coupled semiconductor lasers.

PubMed

Porte, Xavier; Soriano, Miguel C; Brunner, Daniel; Fischer, Ingo

2016-06-15

We experimentally demonstrate a key exchange cryptosystem based on the phenomenon of identical chaos synchronization. In our protocol, the private key is symmetrically generated by the two communicating partners. It is built up from the synchronized bits occurring between two current-modulated bidirectionally coupled semiconductor lasers with additional self-feedback. We analyze the security of the exchanged key and discuss the amplification of its privacy. We demonstrate private key generation rates up to 11  Mbit/s over a public channel.

Semiannual Report, October 1, 1989 through March 31, 1990 (Institute for Computer Applications in Science and Engineering)

DTIC Science & Technology

1990-06-01

synchronization . We consider the performance of various synchronization protocols by deriving upper and lower bounds on optimal perfor- mance, upper bounds on Time ...from universities and from industry, who have resident appointments for limited periods of time , and by consultants. Members of NASA’s research staff...convergence to steady state is also being studied together with D. Gottlieb. The idea is to generalize the concept of local- time stepping by minimizing the

Technologies for unattended network operations

NASA Technical Reports Server (NTRS)

Jaworski, Allan; Odubiyi, Jide; Holdridge, Mark; Zuzek, John

1991-01-01

The necessary network management functions for a telecommunications, navigation and information management (TNIM) system in the framework of an extension of the ISO model for communications network management are described. Various technologies that could substantially reduce the need for TNIM network management, automate manpower intensive functions, and deal with synchronization and control at interplanetary distances are presented. Specific technologies addressed include the use of the ISO Common Management Interface Protocol, distributed artificial intelligence for network synchronization and fault management, and fault-tolerant systems engineering.

Management strategies for ovulation induction in women with polycystic ovary syndrome and known clomifene citrate resistance.

PubMed

Palomba, Stefano; Falbo, Angela; Zullo, Fulvio

2009-12-01

Clomifene citrate is the first and the most used agent for inducing ovulation in patients affected by polycystic ovary syndrome (PCOS). About 60-85% of PCOS women ovulated under clomifene citrate, whereas the others were defined clomifene citrate-resistant. The purpose of the current review will be to describe treatment strategies to induce ovulation in infertile PCOS patients with clomifene citrate resistance. Clomifene citrate and metformin association are a valid option for inducing ovulation in clomifene citrate-resistant PCOS patients. Surgical ovulation induction by laparoscopic ovarian drilling should be reserved to well selected cases. Excellent preliminary results are obtained using new drug formulations, such as aromatase inhibitors. In clomifene citrate-resistant PCOS patients, clomifene citrate and metformin combination and laparoscopic ovarian drilling, in selected cases, should be considered before gonadotropin administration. The efficacy of the other treatments must be confirmed in future well designed studies.

Robust relativistic bit commitment

NASA Astrophysics Data System (ADS)

Chakraborty, Kaushik; Chailloux, André; Leverrier, Anthony

2016-12-01

Relativistic cryptography exploits the fact that no information can travel faster than the speed of light in order to obtain security guarantees that cannot be achieved from the laws of quantum mechanics alone. Recently, Lunghi et al. [Phys. Rev. Lett. 115, 030502 (2015), 10.1103/PhysRevLett.115.030502] presented a bit-commitment scheme where each party uses two agents that exchange classical information in a synchronized fashion, and that is both hiding and binding. A caveat is that the commitment time is intrinsically limited by the spatial configuration of the players, and increasing this time requires the agents to exchange messages during the whole duration of the protocol. While such a solution remains computationally attractive, its practicality is severely limited in realistic settings since all communication must remain perfectly synchronized at all times. In this work, we introduce a robust protocol for relativistic bit commitment that tolerates failures of the classical communication network. This is done by adding a third agent to both parties. Our scheme provides a quadratic improvement in terms of expected sustain time compared with the original protocol, while retaining the same level of security.

The 9-day CIDR-PG protocol: Incorporation of PGF2α pretreatment into a long-term progestin-based estrus synchronization protocol for postpartum beef cows.

PubMed

Thomas, Jordan M; Bishop, Brianne E; Abel, Jillian M; Ellersieck, Mark R; Smith, Michael F; Patterson, David J

2016-06-01

A pilot experiment was designed to test the hypothesis that administration of PGF2α before progestin treatment would allow for a reduced duration of progestin treatment in a long-term progestin-based estrus synchronization protocol. A modified presynchronization treatment was compared with a standard long-term controlled internal drug release (CIDR) treatment, and treatments were compared on the basis of ovarian follicular dynamics, estrous response rate, synchrony of estrus expression, and pregnancy rates resulting from timed artificial insemination (TAI) in postpartum beef cows. Estrous was synchronized for 85 cows, with cows assigned to one of two treatments based on age, days postpartum, and body condition score. Cows assigned to the 14-day CIDR-PG protocol received a CIDR insert (1.38 g progesterone) on Day 0, CIDR removal on Day 14, and administration of PGF2α (25 mg im) on Day 30. Cows assigned to the 9-day CIDR-PG protocol received PGF2α concurrent with CIDR insertion on Day 5, PGF2α concurrent with CIDR removal on Day 14, and administration of PGF2α on Day 30. In both treatments, split-time AI was performed based on estrous response. At 72 hours after PGF2α (Day 33), cows having expressed estrus received TAI; cows that failed to express estrus by 72 hours received TAI 24 hours later (96 hours after PGF2α on Day 34), with GnRH (100 μg im) administered to nonestrous cows. Estrus-detection transmitters were used from CIDR removal until AI to determine onset time of estrus expression both after CIDR removal and after PGF2α. Ovarian ultrasonography was performed at CIDR removal on Day 14, PGF2α on Day 30, and AI on Days 33 or 34. At CIDR removal on Day 14, diameter of the largest follicle present on the ovary was similar between treatments. The proportion of cows expressing estrus after CIDR removal tended to be higher (P = 0.09) among cows assigned to the 9-day CIDR-PG treatment (93%; 40 of 43) than among cows assigned to the 14-day CIDR-PG treatment (81%; 34 of 42). After PGF2α, a significantly higher proportion (P = 0.02) of cows expressed estrus after synchronization with the 9-day CIDR-PG treatment (91%; 39 of 43) than the 14-day CIDR-PG treatment (69%; 29 of 42). Consequently, pregnancy rate to TAI tended to be increased (P = 0.09) among the 9-day CIDR-PG treatment (76.7%; 33 of 43) compared with the 14-day CIDR-PG treatment (59.5%; 25 of 42). In summary, a long-term CIDR-based estrous synchronization protocol for postpartum beef cows was enhanced through administration of PGF2α at CIDR insertion and CIDR removal. Copyright © 2016 Elsevier Inc. All rights reserved.

Gestational length assignment based on last menstrual period, first trimester crown-rump length, ovulation, and implantation timing.

PubMed

Mahendru, Amita A; Wilhelm-Benartzi, Charlotte S; Wilkinson, Ian B; McEniery, Carmel M; Johnson, Sarah; Lees, Christoph

2016-10-01

Understanding the natural length of human pregnancy is central to clinical care. However, variability in the reference methods to assign gestational age (GA) confound our understanding of pregnancy length. Assignation from ultrasound measurement of fetal crown-rump length (CRL) has superseded that based on last menstrual period (LMP). Our aim was to estimate gestational length based on LMP, ultrasound CRL, and implantation that were known, compared to pregnancy duration assigned by day of ovulation. Prospective study in 143 women trying to conceive. In 71 ongoing pregnancies, gestational length was estimated from LMP, CRL at 10-14 weeks, ovulation, and implantation day. For each method of GA assignment, the distribution in observed gestational length was derived and both agreement and correlation between the methods determined. Median ovulation and implantation days were 16 and 27, respectively. The gestational length based on LMP, CRL, implantation, and ovulation was similar: 279, 278, 276.5 and 276.5 days, respectively. The distributions for observed gestational length were widest where GA was assigned from CRL and LMP and narrowest when assigned from implantation and ovulation day. The strongest correlation for gestational length assessment was between ovulation and implantation (r = 0.98) and weakest between CRL and LMP (r = 0.88). The most accurate method of predicting gestational length is ovulation day, and this agrees closely with implantation day. Prediction of gestational length from CRL and known LMP are both inferior to ovulation and implantation day. This information could have important implications on the routine assignment of gestational age.

Time Synchronization Prototype, Server Upgrade Procedure Support and Remote Software Development

NASA Technical Reports Server (NTRS)

Sanders, Shania R.

2014-01-01

Networks are roadways of communication that connect devices. Like all roadways, there are rules and regulations that govern whatever (information in this case) travels along them. One type of rule that is commonly used is called a protocol. More specifically, a protocol is a standard that specifies how data should be transmitted over a network. The project outlined in this document seeks to implement one protocol in particular, Precision Time Protocol, within the Kennedy Ground Control Subsystem network at Kennedy Space Center. This document also summarizes work completed for server upgrades, remote software developer training and how all three assignments demonstrated the importance of accountability and security.

Ovulation induction in women with polycystic ovary syndrome.

PubMed

Perales-Puchalt, Alfredo; Legro, Richard S

2013-08-01

Polycystic ovary syndrome (PCOS) is the most common cause of anovulatory infertility. There are multiple ways to induce ovulation in PCOS patients, which will eventually provide a successful live birth. Each of these treatments varies in aggressiveness and effectiveness. Ranging from lifestyle modifications, through insulin-sensitizing agents, selective estrogen receptor modulators, aromatase inhibitors, gonadotropins, to laparoscopic ovarian drilling and assisted reproductive techniques, each method achieves ovulation induction through different mechanisms of action. This review provides a description and specific characteristics of the different methods used for ovulation induction which can help to design a personalized approach to each PCOS patient, and a general stepwise approach to ovulation induction in these patients. Copyright © 2013 Elsevier Inc. All rights reserved.

Developing a Complete and Effective ACT-R Architecture

DTIC Science & Technology

2008-01-01

of computational primitives , as contrasted with the predominant “one-off” and “grab-bag” cognitive models in the field. These architectures have...transport/ semaphore protocols connected via a glue script. Both protocols rely on the fact that file rename and file remove operations are atomic...the Trial Log file until just prior to processing the next input request. Thus, to perform synchronous identifications it is necessary to run an

Performance and evaluation of real-time multicomputer control systems

NASA Technical Reports Server (NTRS)

Shin, K. G.

1985-01-01

Three experiments on fault tolerant multiprocessors (FTMP) were begun. They are: (1) measurement of fault latency in FTMP; (2) validation and analysis of FTMP synchronization protocols; and investigation of error propagation in FTMP.

A Self-Stabilizing Hybrid-Fault Tolerant Synchronization Protocol

NASA Technical Reports Server (NTRS)

Malekpour, Mahyar R.

2014-01-01

In this report we present a strategy for solving the Byzantine general problem for self-stabilizing a fully connected network from an arbitrary state and in the presence of any number of faults with various severities including any number of arbitrary (Byzantine) faulty nodes. Our solution applies to realizable systems, while allowing for differences in the network elements, provided that the number of arbitrary faults is not more than a third of the network size. The only constraint on the behavior of a node is that the interactions with other nodes are restricted to defined links and interfaces. Our solution does not rely on assumptions about the initial state of the system and no central clock nor centrally generated signal, pulse, or message is used. Nodes are anonymous, i.e., they do not have unique identities. We also present a mechanical verification of a proposed protocol. A bounded model of the protocol is verified using the Symbolic Model Verifier (SMV). The model checking effort is focused on verifying correctness of the bounded model of the protocol as well as confirming claims of determinism and linear convergence with respect to the self-stabilization period. We believe that our proposed solution solves the general case of the clock synchronization problem.

Follicular synchronization using transdermal estradiol patch and GnRH antagonists in the luteal phase; does it increase oocyte yield in poor responders to gonadotropin stimulation for in vitro fertilization (IVF)? A comparative study with microdose flare-up protocol.

PubMed

Ata, Baris; Zeng, Xing; Son, Weon Y; Holzer, Hananel; Tan, Seang L

2011-11-01

The aim of this retrospective study was to compare the oocyte yield with the luteal estradiol patch (LPA) - GnRH antagonist and microdose (MD) flare-up protocols in anticipated poor responders. Fifty-seven women who underwent IVF treatment following stimulation with LPA or MD protocols at McGill Reproductive Centre were matched for age and markers of ovarian reserve. Numbers of oocytes collected (6 vs 7), mature oocytes collected (5 vs 5), and oocyte maturation rates (72% vs 74%) were similar. The numbers of good quality embryos available (2 vs 1) and embryos transferred (3 vs 3) were likewise similar. Embryo implantation rate of 16.7% and clinical pregnancy rate of 38.9% achieved in the LPA group were almost 50% higher than the corresponding figures at 10.3% and 22.2% in the MD group; however, the differences were not statistically significant (p > 0.05 for all comparisons). Although the results do not suggest an increased oocyte yield or follicular synchronization with the LPA protocol, the observed trend toward higher embryo implantation and clinical pregnancy rates requires further research.

Synchronization of random bit generators based on coupled chaotic lasers and application to cryptography.

PubMed

Kanter, Ido; Butkovski, Maria; Peleg, Yitzhak; Zigzag, Meital; Aviad, Yaara; Reidler, Igor; Rosenbluh, Michael; Kinzel, Wolfgang

2010-08-16

Random bit generators (RBGs) constitute an important tool in cryptography, stochastic simulations and secure communications. The later in particular has some difficult requirements: high generation rate of unpredictable bit strings and secure key-exchange protocols over public channels. Deterministic algorithms generate pseudo-random number sequences at high rates, however, their unpredictability is limited by the very nature of their deterministic origin. Recently, physical RBGs based on chaotic semiconductor lasers were shown to exceed Gbit/s rates. Whether secure synchronization of two high rate physical RBGs is possible remains an open question. Here we propose a method, whereby two fast RBGs based on mutually coupled chaotic lasers, are synchronized. Using information theoretic analysis we demonstrate security against a powerful computational eavesdropper, capable of noiseless amplification, where all parameters are publicly known. The method is also extended to secure synchronization of a small network of three RBGs.

Differential effects of unilateral lesions in the medial amygdala on spontaneous and induced ovulation.

PubMed

Sanchez, M A; Dominguez, R

1995-01-01

The possible existence of asymmetry in the control of ovulation by the medial amygdala was explored. Unilateral lesions of the medial amygdala were performed on each day of the estrous cycle. The estral index diminished in almost all animals with a lesion in the right side of medial amygdala. Lesions of the right medial amygdala, when performed on diestrus-1, resulted in a significant decrease in the number of rats ovulating compared to controls (4/8 vs. 8/8, p < 0.05). In ovulating animals a significant reduction in the number of ova shed by the left ovary was found (2.2 +/- 0.8 vs. 6.3 +/- 0.8, p < 0.05). Lesions of the stria terminalis performed on diestrus-1 did not affect ovulation. In a second experiment, administration of GnRH did not restore ovulation in rats with lesions of the right medial amygdala. However, sequential injections of PMSG-hCG did result in ovulation by all members of a group of lesioned animals. In this last condition a significant decrease in the number of ova shed by the right ovary was found compared to animals in the lesion-only condition (1.5 +/- 0.5 vs. 6.0 +/- 1.5, p < 0.05). These data suggest that control of ovulation by the medial amygdala is asymmetric and varies during the estrous cycle.

Ovulation-inducing factor: a protein component of llama seminal plasma

PubMed Central

2010-01-01

Background Previously, we documented the presence of ovulation-inducing factor (OIF) in the seminal plasma of llamas and alpacas. The purpose of the study was to define the biochemical characteristics of the molecule(s) in seminal plasma responsible for inducing ovulation. Methods In Experiment 1, llama seminal plasma was centrifuged using filtration devices with nominal molecular mass cut-offs of 30, 10 and 5 kDa. Female llamas (n = 9 per group) were treated i.m. with whole seminal plasma (positive control), phosphate-buffered saline (negative control), or the fraction of seminal plasma equal or higher than 30 kDa, 10 to 30 kDa, 5 to 10 kDa, or < 5 kDa. In Experiment 2, female llamas (n = 7 per group) were given an i.m. dose of seminal plasma treated previously by: 1) enzymatic digestion with proteinase-K, 2) incubation with charcoal-dextran, 3) heating to 65°C, or 4) untreated (control). In Experiment 3, female llamas (n = 10 per group) were given an i.m. dose of pronase-treated or non-treated (control) seminal plasma. In all experiments, llamas were examined by transrectal ultrasonography to detect ovulation and CL formation. Ovulation rate was compared among groups by Fisher's exact test and follicle and CL diameters were compared among groups by analyses of variance or student's t-tests. Results In Experiment 1, all llamas in the equal or higher than 30 kDa and positive control groups ovulated (9/9 in each), but none ovulated in the other groups (P < 0.001). In Experiment 2, ovulations were detected in all llamas in each treatment group; i.e., respective treatments of seminal plasma failed to inactivate the ovulation-inducing factor. In Experiment 3, ovulations were detected in 0/10 llamas given pronase-treated seminal plasma and in 9/10 controls (P < 0.01). Conclusions We conclude that ovulation-inducing factor (OIF) in llama seminal plasma is a protein molecule that is resistant to heat and enzymatic digestion with proteinase K, and has a molecular mass of approximately equal or higher than 30 kDa. PMID:20462434

Does metformin augment the ovulation inducing effects of clomiphene in non-obese women with polycystic ovary syndrome?

PubMed

Chaudhury, Kalyansree; Chaudhury, Sudeshna; Chowdhury, Subhankar

2008-10-01

To decide if metformin augments clomiphene response for ovulation induction in non-obese women with polycystic ovary syndrome, a prospective randomised placebo-controlled trial was undertaken among 27 patients, who were found eligible for this study following clinical assessment and basic investigations. Women with polycystic ovary syndrome, even when non-obese, has increased insulin-resistance and do not respond favourably when treated with clomiphene for ovulation induction. The hypothesis is that by improving insulin- resistance and thus reversing from hyperinsulinaemia towards normal insulin secretion will enhance the responsiveness of these women to ovulation inducing effects of clomiphene. In the metformin group there were 15 patients who were given metformin 500mg orally 8 hourly daily for initial 3 months whereas in the placebo group there were 12 patients who were given folic acid (as placebo) 5mg orally once daily for initial 3 months. Thereafter, all the 27 patients in both groups were treated with clomiphene 50mg orally once daily from day 2 for 5 days in each month for subsequent 3 months. However, metformin and folic acid was continued in the metformin group and placebo group respectively for these subsequent 3 months when these patients were being treated with clomiphene for ovulation induction. Ovulation, as the outcome measure, was assessed by serial transvaginal ultrasound scanning from day 8/ day 9 and serum progesterone estimation on the 7th or 8th day following the ultrasound evidence of ovulation. Ovulation is taken to have occurred when serum progesterone was > or =8 ng/ml. Ovulation was noted to have occurred in 71.11% of the 45 cycles studied in 15 patients in the metformin group whereas ovulation occurred in 11.11% of the 36 cycles studied in 12 patients in the placebo group. This difference was highly statistically significant (p < 0.001) by Fisher's exact test. It can be conducted that metformin augments the ovulation inducing effects of clomiphene in non-obese women with polycystic ovary syndrome.

Follicular wave emergence in Santa Inês ewes subjected to long-term, progesterone-based estrous synchronization protocols at different times of the year.

PubMed

Oliveira, M E F; Ayres, H; Oliveira, L G; Oba, E; Kridli, R T; Bartlewski, P M; Fonseca, J F; Bicudo, S D; Vicente, W R R

2016-11-01

This study was conducted to document the pattern of antral follicular wave emergence throughout the 14-day, progesterone (P 4 )-based estrous synchronization protocol in ewes that were maintained in subtropical conditions, during the period of increasing day lengths (ID), decreasing day lengths (DD), and the transitional period (TP). In addition, the influence of ovarian status (i.e., size of ovarian antral follicles and the presence of corpora lutea) at the outset of P 4 treatment on ensuing ovarian follicular wave development was examined. Sexually mature Santa Inês ewes (n=70) were subjected to one of the two estrous synchronization protocols in the three seasons. On Day 0, the ewes received an i.m. injection of prostaglandin F 2α and an intravaginal P 4 -releasing device that remained in place for 14days (G-1CIDR) or was replaced on Day 7 (G-2CIDR). Daily ultrasonography of ovaries was conducted from Days 0 to 15. Mean (±SEM) numbers of follicular waves per ewe were 3.7±0.1 and 3.6±0.1 for G-1CIDR and G-2CIDR (P>0.05). The number of emerging follicular waves was greater (P<0.05) during the ID period than during the TP and DD periods (4.0±0.1, 3.4±0.1 and 3.6±0.1, respectively). The presence of medium-sized antral follicles (4.0 to 5.75mm) in the absence of corpora lutea at the time of CIDR insertion tended to advance follicular wave emergence. Although the long-term P 4 treatment was not originally designed to synchronize follicular waves, there was a distinctive pattern of follicular wave dynamics during the period of application of CIDRs that was affected mainly by the number of emerging follicular waves and ovarian status at CIDR insertion. Copyright © 2016 Elsevier B.V. All rights reserved.

Extended-Release Metformin Does Not Reduce the Clomiphene Citrate Dose Required to Induce Ovulation in Polycystic Ovary Syndrome

PubMed Central

Cataldo, Nicholas A.; Barnhart, Huiman X.; Legro, Richard S.; Myers, Evan R.; Schlaff, William D.; Carr, Bruce R.; Diamond, Michael P.; Carson, Sandra A.; Steinkampf, Michael P.; Coutifaris, Christos; McGovern, Peter G.; Gosman, Gabriella; Nestler, John E.; Giudice, Linda C.

2008-01-01

Context: When used for ovulation induction, higher doses of clomiphene may lead to antiestrogenic side effects that reduce fecundity. It has been suggested that metformin in combination with clomiphene can restore ovulation to some clomiphene-resistant anovulators with polycystic ovary syndrome (PCOS). Objective: Our objective was to determine if cotreatment with extended-release metformin (metformin XR) can lower the threshold dose of clomiphene needed to induce ovulation in women with PCOS. Design: A secondary analysis of data from the National Institute of Child Health and Human Development Cooperative Multicenter Reproductive Medicine Network prospective, double-blind, placebo-controlled multicenter clinical trial, Pregnancy in Polycystic Ovary Syndrome, was performed. Setting: Study volunteers at multiple academic medical centers were included. Participants: Women with PCOS and elevated serum testosterone who were randomized to clomiphene alone or with metformin (n = 209 in each group) were included in the study. Interventions: Clomiphene citrate, 50 mg daily for 5 d, was increased to 100 and 150 mg in subsequent cycles if ovulation was not achieved; half also received metformin XR, 1000 mg twice daily. Treatment was for up to 30 wk or six cycles, or until first pregnancy. Main Outcome Measures: Ovulation was confirmed by a serum progesterone more than or equal to 5 ng/ml, drawn prospectively every 1–2 wk. Results: The overall prevalence of at least one ovulation after clomiphene was 75 and 83% (P = 0.04) for the clomiphene-only and clomiphene plus metformin groups, respectively. Using available data from 314 ovulators, the frequency distribution of the lowest clomiphene dose (50, 100, or 150 mg daily) resulting in ovulation was indistinguishable between the two treatment groups. Conclusion: Metformin XR does not reduce the lowest dose of clomiphene that induces ovulation in women with PCOS. PMID:18505764

Comparison of Ovulation Induction Protocols After Endometrioma Resection

PubMed Central

Yasa, Cenk; Dural, Ozlem; Mutlu, Mehmet Firat; Celik, Cem; Ugurlucan, Funda Gungor; Buyru, Faruk

2014-01-01

Background and Objectives: The aim of this study was to compare the in vitro fertilization (IVF) outcomes of long gonadotropin-releasing hormone agonist (GnRH-a) and GnRH-antagonist (GnRH-ant) protocols in endometriosis patients who have undergone laparoscopic endometrioma resection surgery. To our knowledge, there is no study in the current literature that compares the effectiveness of long GnRH-a and GnRH-ant protocols in management of IVF cycles in endometriosis patients who underwent laparoscopic endometrioma resection surgery. Methods: Eighty-six patients with stage III to IV endometriosis who had undergone laparoscopic resection surgery for endometrioma were divided into 2 groups: those who had ovarian stimulation with a long GnRH-a protocol (n = 44), and those who had ovarian stimulation with a GnRH-ant protocol (n = 42). Results: The number of follicles on human chorionic gonadotropin injection day, duration of hyperstimulation, number of retrieved metaphase II oocytes, and total number of grade 1 embryos were statically significantly higher in the long GnRH-a protocol. There were no significant differences in positive β-human chorionic gonadotropin pregnancy rates (25% vs 21.4%; P = .269) and ongoing pregnancy rates per patient (20.5% vs 19.1%; P = .302) between the 2 protocols. Conclusions: Long GnRH-a and GnRH-ant protocols both present similar IVF outcomes in patients with endometriosis who have undergone laparoscopic endometrioma resection surgery. A long GnRH-a protocol may lead to a higher number of embryos that can be cryopreserved, providing the possibility of additional embryo transfers without having to go through the process of ovarian stimulation again. PMID:25392665

Transcriptional changes during ovule development in two genotypes of litchi (Litchi chinensis Sonn.) with contrast in seed size.

PubMed

Pathak, Ashish K; Singh, Sudhir P; Gupta, Yogesh; Gurjar, Anoop K S; Mantri, Shrikant S; Tuli, Rakesh

2016-11-08

Litchi chinensis is a subtropical fruit crop, popular for its nutritional value and taste. Fruits with small seed size and thick aril are desirable in litchi. To gain molecular insight into gene expression that leads to the reduction in the size of seed in Litchi chinensis, transcriptomes of two genetically closely related genotypes, with contrasting seed size were compared in developing ovules. The cDNA library constructed from early developmental stages of ovules (0, 6, and 14 days after anthesis) of bold- and small-seeded litchi genotypes yielded 303,778,968 high quality paired-end reads. These were de-novo assembled into 1,19,939 transcripts with an average length of 865 bp. A total of 10,186 transcripts with contrast in expression were identified in developing ovules between the small- and large- seeded genotypes. A majority of these differences were present in ovules before anthesis, thus suggesting the role of maternal factors in seed development. A number of transcripts indicative of metabolic stress, expressed at higher level in the small seeded genotype. Several differentially expressed transcripts identified in such ovules showed homology with Arabidopsis genes associated with different stages of ovule development and embryogenesis.

Ovarian responses of dairy buffalo cows to timed artificial insemination protocol, using new or used progesterone devices, during the breeding season (autumn-winter).

PubMed

Monteiro, Bruno Moura; de Souza, Diego Cavalcante; Vasconcellos, Guilherme Souza Floriano Machado; Corrêa, Thalita Bueno; Vecchio, Domenico; de Sá Filho, Manoel Francisco; de Carvalho, Nelcio Antonio Tonizza; Baruselli, Pietro Sampaio

2016-01-01

This study evaluated the effect of new or used P4 devices on the ovarian responses of dairy buffalo that were administered an estradiol (E2) plus progesterone (P4)-based timed artificial insemination (TAI) protocol during the breeding season. On the first day of the TAI protocol, 142 cows were randomly assigned to receive one of the following: a new device (New; 1.0 g of P4; n = 48); a device that had previously been used for 9 days (Used1x, n = 47); or a device that had previously been used for 18 days (Used2x, n = 47). Ultrasound was used to evaluate the following: the presence of a corpus luteum (CL); the diameter of the dominant follicle (ØDF) during protocol; ovulatory response; and pregnancies per AI (P/AI). Despite similar responses among the treatments, there was a significant positive association of the ØDF during TAI protocol with ovulatory responses and number of pregnancies. In conclusion, satisfactory ovarian responses and a satisfactory pregnancy rate were achieved when grazing dairy buffalo were subjected to the TAI protocol in breeding season, independent of whether a new or used P4 device was used. Furthermore, the presence of the larger follicle was associated with a higher ovulation rate and higher P/AI following TAI. © 2015 Japanese Society of Animal Science.

Microdose gonadotropin-releasing hormone agonist flare-up protocol versus multiple dose gonadotropin-releasing hormone antagonist protocol in poor responders undergoing intracytoplasmic sperm injection-embryo transfer cycle.

PubMed

Kahraman, Korhan; Berker, Bulent; Atabekoglu, Cem Somer; Sonmezer, Murat; Cetinkaya, Esra; Aytac, Rusen; Satiroglu, Hakan

2009-06-01

To compare the efficacy of microdose GnRH agonist (GnRH-a) flare-up and multiple dose GnRH antagonist protocols in patients who have a poor response to a long luteal GnRH-a protocol. Prospective, randomized, clinical study. University hospital. Forty-two poor responder patients undergoing intracytoplasmic sperm injection (ICSI)-embryo transfer cycle. Twenty-one patients received microdose leuprolide acetate (LA) (50 microg twice daily) starting on the second day of withdrawal bleeding. The other 21 patients received 0.25 mg of cetrorelix daily when the leading follicle reached 14 mm in diameter. Serum E(2) levels, number of growing follicles and mature oocytes, embryo quality, dose of gonadotropin used, cancellation, fertilization, implantation rate and pregnancy rate (PR). The mean serum E(2) concentration on the day of hCG administration was significantly higher in the microdose GnRH-a group than in the GnRH antagonist group (1,904 vs. 1,362 pg/mL). The clinical PRs per started cycle of microdose GnRH-a and GnRH antagonist groups were 14.2% and 9.5%, respectively. There were no statistically significant differences in the other ovulation induction characteristics, fertilization and implantation rates. Microdose GnRH-a flare-up protocol and multiple dose GnRH antagonist protocol seem to have similar efficacy in improving treatment outcomes of poor responder patients.

Suppression of anomalous synchronization and nonstationary behavior of neural network under small-world topology

NASA Astrophysics Data System (ADS)

Boaretto, B. R. R.; Budzinski, R. C.; Prado, T. L.; Kurths, J.; Lopes, S. R.

2018-05-01

It is known that neural networks under small-world topology can present anomalous synchronization and nonstationary behavior for weak coupling regimes. Here, we propose methods to suppress the anomalous synchronization and also to diminish the nonstationary behavior occurring in weakly coupled neural network under small-world topology. We consider a network of 2000 thermally sensitive identical neurons, based on the model of Hodgkin-Huxley in a small-world topology, with the probability of adding non local connection equal to p = 0 . 001. Based on experimental protocols to suppress anomalous synchronization, as well as nonstationary behavior of the neural network dynamics, we make use of (i) external stimulus (pulsed current); (ii) biologic parameters changing (neuron membrane conductance changes); and (iii) body temperature changes. Quantification analysis to evaluate phase synchronization makes use of the Kuramoto's order parameter, while recurrence quantification analysis, particularly the determinism, computed over the easily accessible mean field of network, the local field potential (LFP), is used to evaluate nonstationary states. We show that the methods proposed can control the anomalous synchronization and nonstationarity occurring for weak coupling parameter without any effect on the individual neuron dynamics, neither in the expected asymptotic synchronized states occurring for large values of the coupling parameter.

The aryl hydrocarbon receptor is required for normal gonadotropin responsiveness in the mouse ovary.

PubMed

Barnett, Kimberly R; Tomic, Dragana; Gupta, Rupesh K; Babus, Janice K; Roby, Katherine F; Terranova, Paul F; Flaws, Jodi A

2007-08-15

The aryl hydrocarbon receptor (AHR) mediates the toxicity of a variety of environmental chemicals. Although little is known about the physiological role of the AHR, studies suggest that it plays an important role in regulating ovulation because Ahr deficient (AhRKO) mice have a reduced number of ovulations compared to wild-type (WT) mice. The reasons for the reduced ability of AhRKO mice to ovulate are unknown. Normal ovulation, however, requires estrous cyclicity, appropriate luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels, and LH and FSH responsiveness. Thus, the purpose of this study was to test the hypothesis that Ahr deletion regulates ovulation by altering cyclicity, FSH and LH levels, follicle-stimulating hormone receptor (Fshr) and luteinizing hormone receptor (Lhcgr) levels and/or gonadotropin responsiveness. The data indicate that AhRKO and WT mice have similar levels of FSH and LH, but AhRKO mice have reduced Fshr and Lhcgr mRNA levels compared to WT mice. Furthermore, AhRKO ovaries contain fewer corpora lutea compared to WT ovaries after 5 IU equine chorionic gonadotropin (eCG) treatment. Lastly, both AhRKO and WT mice ovulate a similar number of eggs in response to 5 IU human chorionic gonadotropin (hCG), but AhRKO mice ovulate fewer eggs than WT mice in response to 2.5 IU and 1.25 IU hCG. Collectively, these data indicate that AhRKO follicles have a reduced capacity to ovulate compared to WT follicles and that this is due to reduced responsiveness to gonadotropins. Thus, in addition to mediating toxicity of environmental chemicals, the Ahr is required for normal ovulation.

Transcriptome analysis and gene expression profiling of abortive and developing ovules during fruit development in hazelnut.

PubMed

Cheng, Yunqing; Liu, Jianfeng; Zhang, Huidi; Wang, Ju; Zhao, Yixin; Geng, Wanting

2015-01-01

A high ratio of blank fruit in hazelnut (Corylus heterophylla Fisch) is a very common phenomenon that causes serious yield losses in northeast China. The development of blank fruit in the Corylus genus is known to be associated with embryo abortion. However, little is known about the molecular mechanisms responsible for embryo abortion during the nut development stage. Genomic information for C. heterophylla Fisch is not available; therefore, data related to transcriptome and gene expression profiling of developing and abortive ovules are needed. In this study, de novo transcriptome sequencing and RNA-seq analysis were conducted using short-read sequencing technology (Illumina HiSeq 2000). The results of the transcriptome assembly analysis revealed genetic information that was associated with the fruit development stage. Two digital gene expression libraries were constructed, one for a full (normally developing) ovule and one for an empty (abortive) ovule. Transcriptome sequencing and assembly results revealed 55,353 unigenes, including 18,751 clusters and 36,602 singletons. These results were annotated using the public databases NR, NT, Swiss-Prot, KEGG, COG, and GO. Using digital gene expression profiling, gene expression differences in developing and abortive ovules were identified. A total of 1,637 and 715 unigenes were significantly upregulated and downregulated, respectively, in abortive ovules, compared with developing ovules. Quantitative real-time polymerase chain reaction analysis was used in order to verify the differential expression of some genes. The transcriptome and digital gene expression profiling data of normally developing and abortive ovules in hazelnut provide exhaustive information that will improve our understanding of the molecular mechanisms of abortive ovule formation in hazelnut.

The aryl hydrocarbon receptor is required for normal gonadotropin responsiveness in the mouse ovary

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barnett, Kimberly R.; Tomic, Dragana; Gupta, Rupesh K.

2007-08-15

The aryl hydrocarbon receptor (AHR) mediates the toxicity of a variety of environmental chemicals. Although little is known about the physiological role of the AHR, studies suggest that it plays an important role in regulating ovulation because Ahr deficient (AhRKO) mice have a reduced number of ovulations compared to wild-type (WT) mice. The reasons for the reduced ability of AhRKO mice to ovulate are unknown. Normal ovulation, however, requires estrous cyclicity, appropriate luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels, and LH and FSH responsiveness. Thus, the purpose of this study was to test the hypothesis that Ahr deletion regulatesmore » ovulation by altering cyclicity, FSH and LH levels, follicle-stimulating hormone receptor (Fshr) and luteinizing hormone receptor (Lhcgr) levels and/or gonadotropin responsiveness. The data indicate that AhRKO and WT mice have similar levels of FSH and LH, but AhRKO mice have reduced Fshr and Lhcgr mRNA levels compared to WT mice. Furthermore, AhRKO ovaries contain fewer corpora lutea compared to WT ovaries after 5 IU equine chorionic gonadotropin (eCG) treatment. Lastly, both AhRKO and WT mice ovulate a similar number of eggs in response to 5 IU human chorionic gonadotropin (hCG), but AhRKO mice ovulate fewer eggs than WT mice in response to 2.5 IU and 1.25 IU hCG. Collectively, these data indicate that AhRKO follicles have a reduced capacity to ovulate compared to WT follicles and that this is due to reduced responsiveness to gonadotropins. Thus, in addition to mediating toxicity of environmental chemicals, the Ahr is required for normal ovulation.« less

A wide range real-time synchronous demodulation system for the dispersion interferometer on HL-2M

NASA Astrophysics Data System (ADS)

Wu, Tongyu; Zhang, Wei; Yin, Zejie

2017-09-01

A real-time synchronous demodulation system has been developed for the dispersion interferometer on a HL-2M tokamak. The system is based on the phase extraction method which uses a ratio of modulation amplitudes. A high-performance field programmable gate array with pipeline process capabilities is used to realize the real time synchronous demodulation algorithm. A fringe jump correction algorithm is applied to follow the fast density changes of the plasma. By using the Peripheral Component Interconnect Express protocol, the electronics can perform real-time density feedback with a temporal resolution of 100 ns. Some experimental results presented show that the electronics can obtain a wide measurement range of 2.28 × 1022 m-2 with high precision.

Public channel cryptography: chaos synchronization and Hilbert's tenth problem.

PubMed

Kanter, Ido; Kopelowitz, Evi; Kinzel, Wolfgang

2008-08-22

The synchronization process of two mutually delayed coupled deterministic chaotic maps is demonstrated both analytically and numerically. The synchronization is preserved when the mutually transmitted signals are concealed by two commutative private filters, a convolution of the truncated time-delayed output signals or some powers of the delayed output signals. The task of a passive attacker is mapped onto Hilbert's tenth problem, solving a set of nonlinear Diophantine equations, which was proven to be in the class of NP-complete problems [problems that are both NP (verifiable in nondeterministic polynomial time) and NP-hard (any NP problem can be translated into this problem)]. This bridge between nonlinear dynamics and NP-complete problems opens a horizon for new types of secure public-channel protocols.

Anovulation and ovulation induction

PubMed Central

Katsikis, I; Kita, M; Karkanaki, A; Prapas, N; Panidis, D

2006-01-01

Conventional treatment of normogonadotropic anovulatory infertility is ovulation induction using the antiestrogen clomiphene citrate, followed by follicle-stimulating hormone. Multiple follicle development, associated with ovarian hyperstimulation, and multiple pregnancy remain the major complications. Cumulative singleton and multiple pregnancy rate data after different induction treatments are needed. Newer ovulation induction interventions, such as insulin-sensitizing drugs, aromatase inhibitors and laparoscopic ovarian electrocoagulation, should be compared with conventional treatments. Ovulation induction efficiency might improve if patient subgroups with altered chances for success or complications with new or conventional techniques could be identified, using multivariate prediction models based on initial screening characteristics. This would make ovulation induction more cost-effective, safe and convenient, enabling doctors to advise patients on the most effective and patient-tailored treatment strategy. PMID:20351807

Hack-proof Synchronization Protocol for Multi-player Online Games

NASA Astrophysics Data System (ADS)

Fung, Yeung Siu; Lui, John C. S.

Modern multi-player online games are popular and attractive because they provide a sense of virtual world experience to users: players can interact with each other on the Internet but perceive a local area network responsiveness. To make this possible, most modern multi-player online games use similar networking architecture that aims to hide the effects of network latency, packet loss, and high variance of delay from players. Because real-time interactivity is a crucial feature from a player's point of view, any delay perceived by a player can affect his/her performance [16]. Therefore, the game client must be able to run and accept new user commands continuously regardless of the condition of the underlying communication channel, and that it will not stop responding because of waiting for update packets from other players. To make this possible, multi-player online games typically use protocols based on "dead-reckoning" [5, 6, 9] which allows loose synchronization between players.

Ovulation leads women to perceive sexy cads as good dads.

PubMed

Durante, Kristina M; Griskevicius, Vladas; Simpson, Jeffry A; Cantú, Stephanie M; Li, Norman P

2012-08-01

Why do some women pursue relationships with men who are attractive, dominant, and charming but who do not want to be in relationships--the prototypical sexy cad? Previous research shows that women have an increased desire for such men when they are ovulating, but it is unclear why ovulating women would think it is wise to pursue men who may be unfaithful and could desert them. Using both college-age and community-based samples, in 3 studies we show that ovulating women perceive charismatic and physically attractive men, but not reliable and nice men, as more committed partners and more devoted future fathers. Ovulating women perceive that sexy cads would be good fathers to their own children but not to the children of other women. This ovulatory-induced perceptual shift is driven by women who experienced early onset of puberty. Taken together, the current research identifies a novel proximate reason why ovulating women pursue relationships with sexy cads, complementing existing research that identifies the ultimate, evolutionary reasons for this behavior.

Ovulation in Drosophila is controlled by secretory cells of the female reproductive tract

PubMed Central

Sun, Jianjun; Spradling, Allan C

2013-01-01

How oocytes are transferred into an oviduct with a receptive environment remains poorly known. We found that glands of the Drosophila female reproductive tract, spermathecae and/or parovaria, are required for ovulation and to promote sperm storage. Reducing total secretory cell number by interferring with Notch signaling during development blocked ovulation. Knocking down expression after adult eclosion of the nuclear hormone receptor Hr39, a master regulator of gland development, slowed ovulation and blocked sperm storage. However, ovulation (but not sperm storage) continued when only canonical protein secretion was compromised in adult glands. Our results imply that proteins secreted during adulthood by the canonical secretory pathway from female reproductive glands are needed to store sperm, while a non-canonical glandular secretion stimulates ovulation. Our results suggest that the reproductive tract signals to the ovary using glandular secretions, and that this pathway has been conserved during evolution. DOI: http://dx.doi.org/10.7554/eLife.00415.001 PMID:23599892

The zinc-finger transcription factor Hindsight regulates ovulation competency of Drosophila follicles

PubMed Central

Deady, Lylah D; Li, Wei

2017-01-01

Follicle rupture, the final step in ovulation, utilizes conserved molecular mechanisms including matrix metalloproteinases (Mmps), steroid signaling, and adrenergic signaling. It is still unknown how follicles become competent for follicle rupture/ovulation. Here, we identify a zinc-finger transcription factor Hindsight (Hnt) as the first transcription factor regulating follicle’s competency for ovulation in Drosophila. Hnt is not expressed in immature stage-13 follicle cells but is upregulated in mature stage-14 follicle cells, which is essential for follicle rupture/ovulation. Hnt upregulates Mmp2 expression in posterior follicle cells (essential for the breakdown of the follicle wall) and Oamb expression in all follicle cells (the receptor for receiving adrenergic signaling and inducing Mmp2 activation). Hnt’s role in regulating Mmp2 and Oamb can be replaced by its human homolog Ras-responsive element-binding protein 1 (RREB-1). Our data suggest that Hnt/RREB-1 plays conserved role in regulating follicle maturation and competency for ovulation. PMID:29256860

Induction of ovarian cystic follicles in sheep.

PubMed

Christman, S A; Bailey, M T; Head, W A; Wheaton, J E

2000-10-01

Cystic follicles are a significant cause of infertility in women, dairy cattle and sheep. Sheep were used as a model to identify factors that may elicit formation of cystic follicles. Insulin resistance and elevated LH activity were tested in overweight ewes because of associations among these factors and the formation of cystic follicles. Sheep were synchronized using a progesterone-releasing pessary and insulin resistance was induced during the synchronization period through administration of bovine somatotropin. Following removal of pessaries follicular growth was stimulated by treatment with eCG or eCG and hCG (PG-600). Follicular growth was monitored via daily transrectal ultrasonography and blood samples were collected for hormonal analyses. Six of 18 ewes had a subnormal or absent preovulatory gonadotropin surge and developed cystic follicles. Neither insulin resistance nor elevated LH activity were associated with formation of cystic follicles. Ewes that developed cystic follicles were heavier (93 +/- 4 kg) than ewes that ovulated (81 +/- 3 kg; P = 0.02). Furthermore, following pessary removal and initiation of daily ultrasonography, ewes that developed cystic follicles lost body weight (-3 +/- 1%), while ovulatory ewes continued to gain body weight (1 +/- 1%; P = 0.005). It is speculated that in heavy ewes metabolic factors associated with acute body weight loss inhibit the positive feedback of estradiol and thereby suppress the preovulatory gonadotropin surge leading to formation of cystic follicles.

Dog cloning with in vivo matured oocytes obtained using electric chemiluminescence immunoassay-predicted ovulation method.

PubMed

Lee, Seunghoon; Zhao, Minghui; No, Jingu; Nam, Yoonseok; Im, Gi-Sun; Hur, Tai-Young

2017-01-01

Radioactive immunoassay (RIA) is a traditional serum hormone assay method, but the application of the method in reproductive studies is limited by the associated radioactivity. The aim of present study was to evaluate the reliability of RIA and to compare its canine serum progesterone concentration determination accuracy to that of the electric chemiluminescence immunoassay (ECLI). In vivo matured oocytes were utilized for canine somatic cell nuclear transfer (SCNT), and serum progesterone levels were assessed to accurately determine ovulation and oocyte maturation. Canine serum progesterone concentrations during both proestrus and estrus were analyzed by RIA and ECLI to determine the ovulation day. Although both methods detected similar progesterone levels before ovulation, the mean progesterone concentration determined using ECLI was significantly higher than of RIA three days before ovulation. Following ovulation, oocytes were collected by surgery, and a lower percentage of mature oocytes were observed using ECLI (39%) as compared to RIA (67%) if 4-8ng/ml of progesterone were used for determination of ovulation. A high percentage of mature oocytes was observed using ECLI when 6-15 ng/mL of progesterone was used for ovulation determination. To determine whether ECLI could be used for canine cloning, six canines were selected as oocyte donors, and two puppies were obtained after SCNT and embryo transfer. In conclusion, compared to the traditional RIA method, the ECLI method is a safe and reliable method for canine cloning.

The Evolutionary Origin of Female Orgasm.

PubMed

Pavličev, Mihaela; Wagner, Günter

2016-09-01

The evolutionary explanation of female orgasm has been difficult to come by. The orgasm in women does not obviously contribute to the reproductive success, and surprisingly unreliably accompanies heterosexual intercourse. Two types of explanations have been proposed: one insisting on extant adaptive roles in reproduction, another explaining female orgasm as a byproduct of selection on male orgasm, which is crucial for sperm transfer. We emphasize that these explanations tend to focus on evidence from human biology and thus address the modification of a trait rather than its evolutionary origin. To trace the trait through evolution requires identifying its homologue in other species, which may have limited similarity with the human trait. Human female orgasm is associated with an endocrine surge similar to the copulatory surges in species with induced ovulation. We suggest that the homolog of human orgasm is the reflex that, ancestrally, induced ovulation. This reflex became superfluous with the evolution of spontaneous ovulation, potentially freeing female orgasm for other roles. This is supported by phylogenetic evidence showing that induced ovulation is ancestral, while spontaneous ovulation is derived within eutherians. In addition, the comparative anatomy of female reproductive tract shows that evolution of spontaneous ovulation is correlated with increasing distance of clitoris from the copulatory canal. In summary, we suggest that the female orgasm-like trait may have been adaptive, however for a different role, namely for inducing ovulation. With the evolution of spontaneous ovulation, orgasm was freed to gain secondary roles, which may explain its maintenance, but not its origin. © 2016 Wiley Periodicals, Inc.

Which insemination results in fertilization when several are performed before ovulation?

PubMed

Clément, F; Vincent, P; Mahla, R; Meriaux, J C; Palmer, E

2000-01-01

The aim of the present study was to determine which artificial insemination results in fertilization when mares are inseminated several times before ovulation. Mares in oestrus were inseminated over 62 cycles with fresh semen at 48 h intervals from when a follicle > or =30 mm in diameter was detected until ovulation. The number of inseminations was limited to three. Three fertile stallions were used and a different stallion was used for each artificial insemination. The order of the three stallions was changed for each cycle. Embryos were collected between day 10 and day 12 after ovulation and paternity was checked using DNA typing. When two inseminations were performed per cycle, 14 of 17 embryos were the result of the insemination performed on days 2-4 before ovulation and three embryos were the result of the insemination performed on days 0-2. When three inseminations were performed, 1 of 6, 2 of 6 and 3 of 6 embryos resulted from the inseminations performed 4-6, 2-4 and 0-2 days before ovulation, respectively. Thus, 17 of 23 (74%) oocytes were not fertilized as a result of the insemination performed 0-2 days before ovulation. The mean interval between fertilization and ovulation in the mares from which embryos were recovered and tested (n=23) was 2.6 +/- 1.0 days. These results indicate that spermatozoa can remain viable in the genital tract of mares for at least 2.6 days.

Growth rate of ovulatory follicles during the first ovulatory oestrus (after seasonal anoestrus) and subsequent oestrous period in Irish Draught mares.

PubMed

Newcombe, John R; Cuervo-Arango, Juan

2013-03-12

It is believed that during the spring transition, the developing follicle tends to grow more slowly, persist longer and grow to a larger diameter prior to ovulation than at subsequent oestrus periods. A general suspicion, that the first ovulation of the year is less fertile than subsequent ovulations could be explained by a slower growth rate of the ovulatory follicle during transition with the consequent production of a subfertile oocyte. By detailed serial examination of the same group of Irish Draught mares over three winter/spring periods, no significant difference was found in either growth rate or pre-ovulatory diameter when compared with subsequent ovulations. Mean growth rates over the ten days prior to ovulation were 2.20 mm/day (range 1.18 to 3.64) and 2.19 mm/day (range 1.25 to 3.41) for first and subsequent ovulations respectively. Mean maximum pre-ovulatory diameters were 44.7 mm (range 35 to 59) and 43.5 mm (range 31 to 57.5) for first and subsequent ovulations respectively. The impression gained by practitioners that the first follicle develops more slowly during the transition to the first ovulation of the season may be due to less frequent examinations and consequently a failure to observe and record that follicles may grow and then regress during this period. The largest follicle observed a few days previously is not necessarily the same large follicle found at a later examination.

Dog cloning with in vivo matured oocytes obtained using electric chemiluminescence immunoassay-predicted ovulation method

PubMed Central

No, Jingu; Nam, Yoonseok; Im, Gi-Sun; Hur, Tai-Young

2017-01-01

Radioactive immunoassay (RIA) is a traditional serum hormone assay method, but the application of the method in reproductive studies is limited by the associated radioactivity. The aim of present study was to evaluate the reliability of RIA and to compare its canine serum progesterone concentration determination accuracy to that of the electric chemiluminescence immunoassay (ECLI). In vivo matured oocytes were utilized for canine somatic cell nuclear transfer (SCNT), and serum progesterone levels were assessed to accurately determine ovulation and oocyte maturation. Canine serum progesterone concentrations during both proestrus and estrus were analyzed by RIA and ECLI to determine the ovulation day. Although both methods detected similar progesterone levels before ovulation, the mean progesterone concentration determined using ECLI was significantly higher than of RIA three days before ovulation. Following ovulation, oocytes were collected by surgery, and a lower percentage of mature oocytes were observed using ECLI (39%) as compared to RIA (67%) if 4-8ng/ml of progesterone were used for determination of ovulation. A high percentage of mature oocytes was observed using ECLI when 6–15 ng/mL of progesterone was used for ovulation determination. To determine whether ECLI could be used for canine cloning, six canines were selected as oocyte donors, and two puppies were obtained after SCNT and embryo transfer. In conclusion, compared to the traditional RIA method, the ECLI method is a safe and reliable method for canine cloning. PMID:28288197

Betacarotene supplementation increases ovulation rate without an increment in LH secretion in cyclic goats.

PubMed

Meza-Herrera, Cesar A; Vargas-Beltran, Fermin; Vergara-Hernandez, Hector P; Macias-Cruz, Ulises; Avendaño-Reyes, Leonel; Rodriguez-Martinez, Rafael; Arellano-Rodriguez, Gerardo; Veliz-Deras, Francisco G

2013-03-01

This study aimed to evaluate the effects of betacarotene (BC) supplementation on ovulation rate (OR) and luteinizing hormone (LH) secretion in adult goats during the breeding season. Additionally, total ovarian activity (TOA) comprising the total number of ultrasonographically detectable antral follicles (AF) and corpora lutea (OR) was also assessed. In early October, adult goats [n=22, 3.5 years of age, 7/8 Sannen-Alpine; 26°N, 103°W at 1117m.a.s.l.] were randomly assigned to: (i) BC group (BCG), orally supplemented with 50mg of BC/goat/day [n=10; live weight (LW)=45.9±2.0kg, body condition score (BCS; range: 0-emaciated to 5-obese)=3.0±0.1], and (ii) control group (CONT) [n=12; LW=46.2±2.0kg, BCS=3.0±0.1]. All animals received a basal diet of alfalfa hay, corn silage and corn grain, with free access to water and mineral salts. The whole experimental period spanned 34 days before and 17 days after ovulation. On day 23 of the experiment, estrus was synchronized with progestin-releasing intravaginal sponges; 36h prior to estrus, an intensive blood sampling (every 15min for 6h) was performed to determine mean LH concentrations, pulsatility (LH-PULSE) and area under the curve (LH-AUC) for serial LH concentrations. Afterwards, by the end of the luteal phase (i.e., 17 days after the onset of estrus), an ultrasonographic scanning was performed to evaluate OR and TOA [AF+OR]. The average LW and BCS did not differ (p>0.05) during the experimental period. BC-supplemented goats showed an increase in OR (3.4±0.2 versus 2.8±0.2; p<0.05) and exhibited lower (p<0.05) serum LH concentrations, LH-AUC and LH-PULSE compared to CONT. A positive correlation was recorded between OR and LW (r(2)=0.42, p<0.05) and BCS (r(2)=0.47, p<0.05). In addition, AF (5.0±0.6 versus 3.4±0.6) and TOA (8.4±0.6 versus 6.2±0.6) were greater (p<0.05) in the BC-supplemented group than CONT. Supplementation with BC enhanced ovarian follicular development and ovulation rate in adult female goats under decreased photoperiods through LHRH-independant pathways or direct effects of BC on ovarian function. Copyright © 2013 Society for Biology of Reproduction & the Institute of Animal Reproduction and Food Research of Polish Academy of Sciences in Olsztyn. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Treatment of lactating dairy cows with gonadotropin-releasing hormone before first insemination during summer heat stress.

PubMed

Voelz, B E; Rocha, L; Scortegagna, F; Stevenson, J S; Mendonça, L G D

2016-09-01

The objectives of the experiments were to compare ovarian responses, pregnancy per artificial insemination, and pattern of insemination of 2 estrus detection-based presynchronization protocols before first artificial insemination (AI) during heat stress. In experiment 1, primiparous lactating dairy cows (n=1,358) from 3 dairies were assigned randomly to 2 treatments at 60±3 (±SD) DIM (study d 0): (1) treatment with 100 µg of GnRH on study d 0 (Gpresynch), or (2) no treatment on study d 0 (control). In experiment 2, multiparous lactating dairy cows (n=1,971) from 3 dairies were assigned randomly to 2 treatments at 49±3 (±SD) DIM (study d 0), similar to experiment 1. In both experiments, PGF2α injections were administered 14 d apart starting on study d 7 for all cows. Cows not inseminated after detection of estrus were submitted to a timed artificial insemination protocol at study d 35. In a subgroup of cows from 2 dairies, concentrations of progesterone were determined from blood samples collected on study d 0 and 7. Furthermore, ovaries were examined by ultrasonography on study d -14, 0, and 7 to determine cyclic status and ovulation in response to GnRH treatment. In experiment 1, progesterone concentration was not different on d 0, but progesterone was increased for Gpresynch compared with control cows on study d 7 (3.6±0.3 vs. 2.7±0.4 ng/mL), respectively. Ovulation risk from study d 0 to 7 was increased for Gpresynch compared with control (50.6 vs. 15.2%). Control cows were inseminated at a faster rate than Gpresynch cows [adjusted hazard ratio (AHR)=0.89, 95% confidence interval=0.80 to 1.00], and the interaction between treatment and dairy affected pregnancy per artificial insemination at 36 and 94 d post-artificial insemination. In experiment 2, concentrations of progesterone did not differ on study d 0 or 7, despite ovulation risk from study d 0 to 7 being greater in Gpresynch than control cows (46.9 vs. 23.8%). The interaction between treatment and dairy affected hazard of insemination with Gpresynch cows from dairy 1 (AHR=1.21; 1.05 to 1.41) being inseminated faster than control cows. Hazard of pregnancy was affected by treatment because Gpresynch cows became pregnant at a faster rate than control cows (AHR=1.25; 1.04 to 1.50). In conclusion, GnRH-based presynchronization protocols initiated before the end of the voluntary waiting period may have benefits in reproductive efficiency of estrus detection-based programs during heat stress. In addition, treatment with GnRH decreased the prevalence of anovular cows at the initiation of PGF2α injections. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Editing wild points in isolation - Fast agreement for reliable systems (Preliminary version)

NASA Technical Reports Server (NTRS)

Kearns, Phil; Evans, Carol

1989-01-01

Consideration is given to the intuitively appealing notion of discarding sensor values which are strongly suspected of being erroneous in a modified approximate agreement protocol. Approximate agreement with editing imposes a time bound upon the convergence of the protocol - no such bound was possible for the original approximate agreement protocol. This new approach is potentially useful in the construction of asynchronous fault tolerant systems. The main result is that a wild-point replacement technique called t-worst editing can be shown to guarantee convergence of the approximate agreement protocol to a valid agreement value. Results are presented for a four-processor synchronous system in which a single processor may be faulty.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jason L. Wright; Milos Manic

Time synchronization and event time correlation are important in wireless sensor networks. In particular, time is used to create a sequence events or time line to answer questions of cause and effect. Time is also used as a basis for determining the freshness of received packets and the validity of cryptographic certificates. This paper presents secure method of time synchronization and event time correlation for TESLA-based hierarchical wireless sensor networks. The method demonstrates that events in a TESLA network can be accurately timestamped by adding only a few pieces of data to the existing protocol.

Embryonic and postnatal telomere length decrease with ovulation order within clutches

PubMed Central

Noguera, José C.; Metcalfe, Neil B.; Reichert, Sophie; Monaghan, Pat

2016-01-01

Telomere length (TL) in early life has been found to be predictive of subsequent lifespan. Factors such as parental TL, parental age and environmental conditions during development have been shown to contribute to the observed variation in TL among individuals. One factor that has not hitherto been considered is ovulation order, although it is well established that the last hatched/born offspring in a brood or litter often show relatively poor subsequent performance. We examined the within- and across-clutch effect of ovulation order on TL in embryos of zebra finches experiencing the same controlled incubation conditions (N = 151), and tested whether any such ovulation order effects remained detectable in adults (N = 122). Irrespective of clutch and egg size, TL in early-stage embryos (72 h incubation) markedly decreased with within-clutch ovulation order; the difference in TL of first and last-laid embryos was equivalent to the average within-individual telomere loss over the entire period of nestling and juvenile life. This ovulation-order effect occurred only within but not across clutches, and was still evident in adults. Given that TL in early life predicts lifespan, our results suggest that parental effects on telomere length could contribute to the known poor performance of later-ovulated family members. PMID:27174767

Self-sterility in Ipomopsis aggregata (Polemoniaceae) is due to prezygotic ovule degeneration.

PubMed

Sage, Tammy L; Price, Mary V; Waser, Nickolas M

2006-02-01

Based on previous studies, extreme (>99%) self-sterility in scarlet gilia (Ipomopsis aggregata) appears to be involved in late-acting ovarian self-incompatibility (OSI). Here, we confirm this suggestion by comparing structural events that follow from cross- vs. self-pollinations of I. aggregata. Growth of cross- and self-pollen tubes in the style at 11 h and growth in the ovary at 24 h was equivalent. Nonetheless, by 24 h, cross-pollen effected a significantly higher percentage of both ovule penetration and fertilization. Ovules in self-pollinated flowers showed pronounced changes, including an absence of embryo sac expansion and reduced starch in the integument, by 11 h post-pollination, well before pollen tube entry into the ovary. In addition, the integumentary tapetum and adjacent 1-3 cell layers exhibited abnormal cell division, pronounced deposition of thick, pectin-rich cell walls, and cellular collapse. Ovules and embryo sacs from cross-pollinated flowers rarely showed such features. Developmental changes in ovules from self-pollinated flowers eventually resulted in integument and embryo sac collapse, a process not observed in ovules of unpollinated flowers. We suggest that OSI involves long-distance signaling between self-pollen or self-pollen tubes and carpel tissue that reduces availability of receptive ovules for fertilization before pollen tubes arrive in the ovary.

The induction of ovulation by pulsatile administration of GnRH: an appropriate method in hypothalamic amenorrhea.

PubMed

Christou, Fotini; Pitteloud, Nelly; Gomez, Fulgencio

2017-08-01

The induction of ovulation by the means of a pump which assures the pulsatile administration of GnRH is a well-known method that applies to women suffering from amenorrhea of hypothalamic origin. Although a simple and efficient method to establish fertility, it is underused. Twelve patients suffering from this condition, 1 Kallmann syndrome, 4 normosmic isolated hypogonadotropic hypogonadism, and 7 functional hypothalamic amenorrhea desiring pregnancy were treated. They underwent one or more cycles of pulsatile GnRH, at a frequency of 90 minutes, either by the intravenous or the subcutaneous route. An initial dose of 5 μg per pulse in the intravenous route was administered and of 15 μg per pulse in the subcutaneous route. The treatment was monitored by regular dosing of gonadotropins, estradiol and progesterone, and the development of follicles and ovulation was monitored by intra-vaginal ultrasonography. All the patients had documented ovulation, after a mean of 17 days on pump stimulation. Single ovulation occurred in 30 of 33 treatment cycles, irrespective of the route of administration. Ovulation resulted in 10 pregnancies over 7 patients (2 pregnancies in 3 of them), distributed in the 3 diagnostic categories. For comparison, a patient with PCOS treated similarly, disclosed premature LH surge without ovulation.

Distribution and change patterns of free IAA, ABP 1 and PM H⁺-ATPase during ovary and ovule development of Nicotiana tabacum L.

PubMed

Chen, Dan; Deng, Yingtian; Zhao, Jie

2012-01-15

Auxin plays key roles in flower induction, embryogenesis, seed formation and seedling development, but little is known about whether auxin regulates the development of ovaries and ovules before pollination. In the present report, we measured the content of free indole-3-acetic (IAA) in ovaries of Nicotiana tabacum L., and localized free IAA, auxin binding protein 1 (ABP1) and plasma membrane (PM) H⁺-ATPase in the ovaries and ovules. The level of free IAA in the developmental ovaries increased gradually from the stages of ovular primordium to the functional megaspore, but slightly decreased when the embryo sacs formed. Immunoenzyme labeling clearly showed that both IAA and ABP1 were distributed in the ovules, the edge of the placenta, vascular tissues and the ovary wall, while PM H⁺-ATPase was mainly localized in the ovules. By using immunogold labeling, the subcellular distributions of IAA, ABP1 and PM H⁺-ATPase in the ovules were also shown. The results suggest that IAA, ABP1 and PM H⁺-ATPase may play roles in the ovary and ovule initiation, formation and differentiation. Crown Copyright © 2011. Published by Elsevier GmbH. All rights reserved.

Role of arachidonic acid and protein kinase C during maturation-inducing hormone-dependent meiotic resumption and ovulation in ovarian follicles of Atlantic croaker

USGS Publications Warehouse

Patino, R.; Yoshizaki, G.; Bolamba, D.; Thomas, P.

2003-01-01

The roles of arachidonic acid (AA) and protein kinase C (PKC) during in vitro maturation-inducing hormone (MIH)-dependent meiotic resumption (maturation) and ovulation were studied in ovarian follicles of Atlantic croaker (Micropogonias undulatus). The requirement for cyclooxygenase (COX) metabolites of AA was examined using a nonspecific COX inhibitor, indomethacin (IM), as well as two COX products, prostaglandin (PG) F2?? and PGE2, whereas the role of lipoxygenase (LOX) was investigated using a specific LOX inhibitor, nordihydroguaiaretic acid (NDGA). The involvement of PKC was examined using phorbol 12-myristate 13-acetate (PMA), a PKC activator, as well as GF109203X (GF), a specific inhibitor of PKC and 1-(5-isoquin- olinesulfonyl)-2-methylpiperazine (H7), nonspecific inhibitor of protein kinases. Genomic mechanisms were examined with the transcription-inhibitor actinomycin D (ActD) and the functionality of heterologous (oocyte-granulosa) gap junctions (GJ) with a dye transfer assay. The AA (100 ??M) and PGF2?? (5 ??M) did not induce maturation, and NDGA (10 ??M) did not affect MIH-dependent maturation. However, IM (100 ??M) partially inhibited MIH-dependent maturation. Conversely, AA and both PGs induced, and IM and NDGA inhibited, MIH-dependent ovulation in matured follicles. The PMA (1 ??g/ml) did not induce maturation but caused ovulation in matured follicles, whereas PKC inhibitors (GF, 5 ??M; H7, 50??M) did not affect MIH-dependent maturation but inhibited MIH- and PMA-dependent ovulation. The PMA-dependent ovulation was inhibited by IM but not by NDGA. In addition, ActD (5 ??M) blocked MIH-dependent, but not PMA-dependent, ovulation, and PGF2?? restored MIH-dependent ovulation in ActD-blocked follicles. The AA and PGs did not induce, and GF did not inhibit, MIH-dependent heterologous GJ uncoupling. In conclusion, AA and PKC mediate MIH-dependent ovulation but not meiotic resumption or heterologous GJ uncoupling in croaker follicles, but a permissive role of COX products of AA during maturation is possible. A novel model of MIH-dependent ovulation is proposed in which 1) LOX and COX metabolites of AA are both required for ovulation, but at upstream and downstream sites of the pathway, respectively, relative to PKC, and 2) PKC is downstream of genomic activation.

14 CFR 431.41 - Communications plan.

Code of Federal Regulations, 2013 CFR

2013-01-01

... direct access to real-time, safety-critical information required for making decisions and issuing... communications during launch and reentry; (3) A protocol is established for utilizing defined radio... that accurately reflects communications made on individual channels, synchronized time coding, and...

14 CFR 431.41 - Communications plan.

Code of Federal Regulations, 2011 CFR

2011-01-01

... direct access to real-time, safety-critical information required for making decisions and issuing... communications during launch and reentry; (3) A protocol is established for utilizing defined radio... that accurately reflects communications made on individual channels, synchronized time coding, and...

14 CFR 431.41 - Communications plan.

Code of Federal Regulations, 2012 CFR

2012-01-01

... direct access to real-time, safety-critical information required for making decisions and issuing... communications during launch and reentry; (3) A protocol is established for utilizing defined radio... that accurately reflects communications made on individual channels, synchronized time coding, and...

14 CFR 431.41 - Communications plan.

Code of Federal Regulations, 2014 CFR

2014-01-01

... direct access to real-time, safety-critical information required for making decisions and issuing... communications during launch and reentry; (3) A protocol is established for utilizing defined radio... that accurately reflects communications made on individual channels, synchronized time coding, and...

Parallel simulation today

NASA Technical Reports Server (NTRS)

Nicol, David; Fujimoto, Richard

1992-01-01

This paper surveys topics that presently define the state of the art in parallel simulation. Included in the tutorial are discussions on new protocols, mathematical performance analysis, time parallelism, hardware support for parallel simulation, load balancing algorithms, and dynamic memory management for optimistic synchronization.

A retrospective study of artificial insemination of 251 mares using chilled and fixed time frozen-thawed semen.

PubMed

Crowe, C A M; Ravenhill, P J; Hepburn, R J; Shepherd, C H

2008-09-01

Historically, artificial insemination (AI) using frozen semen has been perceived to have poorer success rates and be more labour intensive than using chilled semen. A retrospective study was therefore conducted to compare the conception rate achieved by AI between chilled and frozen semen, using fixed time insemination protocols over 2 breeding seasons. Artificial insemination using chilled semen produces a higher conception rate than that achieved with frozen semen. Mares (n = 251) were inseminated with either chilled (n = 112) or frozen (n = 139) semen in the 2006 and 2007 northern hemisphere breeding season. Per rectum ultrasonography of the mare's reproductive tract determined the timing of insemination, and deslorelin acetate was used to induce ovulation. Chilled semen insemination was performed using a single preovulatory dose delivered into the uterine body. Frozen semen was administered as 2 doses (pre- and post ovulation) using a deep uterine insemination technique. Pregnancy was detected ultrasonographically at 15 days post insemination. Conception rates were compared using a Chi-squared test. Insemination with frozen semen produced a significantly (P = 0.022) higher seasonal conception rate (82.0%) than that achieved with chilled semen (69.6%). Insemination with frozen semen can achieve conception rates equal to those with chilled semen, enabling the mare owner a greater selection of stallions.

Do estrogen receptor alpha polymorphisms have any impact on the outcome in an ART program?

PubMed

Anagnostou, Elli; Malamas, Fotodotis; Mavrogianni, Despina; Dinopoulou, Vasiliki; Drakakis, Peter; Kallianidis, Konstantinos; Loutradis, Dimitris

2013-04-01

To investigate two of the most studied estrogen receptor alpha polymorphisms (PvuII and XbaI) in combination, in order to evaluate their impact on an ART program outcome. 203 normally ovulating women who underwent IVF or ICSI treatment were genotyped for PvuII and XbaI polymorphisms in ESR1 intron 1 using Real-Time PCR. The relationship between the presence of polymorphic alleles and the ovulation induction parameters and outcome was examined. Women were grouped according to the number of polymorphic alleles they carried in two groups (0-2 versus 3-4 polymorphic alleles). The presence of 3 or more polymorphic alleles was associated with significantly lower E2 levels on the day of hCG administration and a significantly lower rate of good quality embryos. There is an association between ESR1 polymorphisms and some ART parameters such as the level of E2 on the day of hCG administration and the quality of the embryos. These results underline the importance of ESR1 as a candidate gene for the prediction of ovarian response to IVF/ICSI protocols. Future research work concerning several more genes is necessary for a better evaluation of patients before entering an IVF/ICSI program.

Breast-feeding and postpartum ovulation.

PubMed

Howie, P W; Mcneilly, A S

1982-04-01

This paper reviews the evidence for the contraceptive effects of breastfeeding on postpartum ovulation. In developing countries breastfeeding prevents more pregnancies than all the other methods of contraception. In a detailed Edinburgh longitudinal study of 27 breastfeeding and 10 bottlefeeding mothers, the return of ovarian follicular development and ovulation was determined by several estimations of total urinary estrogen and pregnanedial excretion, respectively. In the bottlefeeding mothers the patterns of events after delivery was consistent. Basal prolactin levels fell to non-pregnant levels within 2-3 weeks postpartum. By 15 weeks all bottlefeeding mothers had resumed ovulation and menstruation. By contrast, all breastfeeding mothers who breastfed for a mean of 40 weeks maintained elevated basal prolactin levels for longer than the bottlefeeders. The mean time to 1st ovulation was 36 weeks with a range between 15-66 weeks postpartum. The infant feeding patterns showed striking differences between these mothers (33% of the whole group) who suppressed ovulation for more than 40 weeks postpartum and the rest of the mothers (67%) who ovulated before that time. The mothers who suppressed ovulation for more than 40 weeks not only maintained breastfeeding for the greatest number of weeks, but also suckled more frequently, breastfed for a longer total time each day, and maintained 1 or more night feeds for a longer time. After supplementary food was given there was a rapid increase in the number of mothers with evidence of ovarian activity and within 16 weeks of starting, 71% had evidence of follicular activity and 52% had ovulated. Mothers who introduce weaning food abruptly and reduce sucking rapidly will be more likely to experience an early return of ovulation and potential fertility. The mechanism of lactational infertility is not clearly understood. 45% of the completed menstrual cycles during lactation were anovular and of the 55% which were ovular, many were associated with defective luteal phases. The birth spacing effect of lactation is of great importance in communities where alternative contraceptive devices are not available or not acceptable. Breastfeeding is a complementary form of contraception.

The effects of calcitriol on improvement of insulin resistance, ovulation and comparison with metformin therapy in PCOS patients: a randomized placebo- controlled clinical trial.

PubMed

Bonakdaran, Shokoufeh; Mazloom Khorasani, Zahra; Davachi, Behrooz; Mazloom Khorasani, Javad

2012-09-01

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in females of reproductive age. Insulin resistance is a frequent metabolic disturbance in PCOS. Vitamin D deficiency is a common problem. Accumulating evidence suggests that vitamin D has a role on insulin sensitivity so may contribute to reduction of hyperandrogenemia. The aim was to determine the effects of vitamin D treatment in metabolic components and ovulation evidence in PCOS. Fifty one untreated PCOS patients were randomly divided into three groups and treated with calcitriol, metformin, or placebo. Before and 3 months after treatment, ovulation evidence was assessed by ovarian trans abdominal sonography. Plasma fasting glucose, insulin, homeostasis model assessment insulin resistance (HOMA-IR), 25-hydroxyvitamin D, parathyroid hormone and androgen levels were measured before and after treatment. A 75gr glucose test was performed before and after treatment and two set of results was compared. Three patients did not continue this study. Only 11 patient (22.9%) had sufficient vitamin D levels (>30 ng/ml). Metformin caused a significant decrease in weight (p=0.027), insulin level (p=0.043), and insulin resistance (p=0.048). Systolic blood pressure and PTH significantly improved after calcitriol (p=0.029, p=0.009 respectively). An improvement in ovulation was detected after calcitriol and seven patients, without evidence of ovulation before treatment, illustrated ovulation after 3 months. Difference with calcitriol in ovulation was significant versus other two methods (p=0.02). Calcitriol treatment in PCOS may be prior to metformin in ovulation induction.

Transcriptional analysis of the Arabidopsis ovule by massively parallel signature sequencing

PubMed Central

Sánchez-León, Nidia; Arteaga-Vázquez, Mario; Alvarez-Mejía, César; Mendiola-Soto, Javier; Durán-Figueroa, Noé; Rodríguez-Leal, Daniel; Rodríguez-Arévalo, Isaac; García-Campayo, Vicenta; García-Aguilar, Marcelina; Olmedo-Monfil, Vianey; Arteaga-Sánchez, Mario; Martínez de la Vega, Octavio; Nobuta, Kan; Vemaraju, Kalyan; Meyers, Blake C.; Vielle-Calzada, Jean-Philippe

2012-01-01

The life cycle of flowering plants alternates between a predominant sporophytic (diploid) and an ephemeral gametophytic (haploid) generation that only occurs in reproductive organs. In Arabidopsis thaliana, the female gametophyte is deeply embedded within the ovule, complicating the study of the genetic and molecular interactions involved in the sporophytic to gametophytic transition. Massively parallel signature sequencing (MPSS) was used to conduct a quantitative large-scale transcriptional analysis of the fully differentiated Arabidopsis ovule prior to fertilization. The expression of 9775 genes was quantified in wild-type ovules, additionally detecting >2200 new transcripts mapping to antisense or intergenic regions. A quantitative comparison of global expression in wild-type and sporocyteless (spl) individuals resulted in 1301 genes showing 25-fold reduced or null activity in ovules lacking a female gametophyte, including those encoding 92 signalling proteins, 75 transcription factors, and 72 RNA-binding proteins not reported in previous studies based on microarray profiling. A combination of independent genetic and molecular strategies confirmed the differential expression of 28 of them, showing that they are either preferentially active in the female gametophyte, or dependent on the presence of a female gametophyte to be expressed in sporophytic cells of the ovule. Among 18 genes encoding pentatricopeptide-repeat proteins (PPRs) that show transcriptional activity in wild-type but not spl ovules, CIHUATEOTL (At4g38150) is specifically expressed in the female gametophyte and necessary for female gametogenesis. These results expand the nature of the transcriptional universe present in the ovule of Arabidopsis, and offer a large-scale quantitative reference of global expression for future genomic and developmental studies. PMID:22442422

Transcriptional analysis of the Arabidopsis ovule by massively parallel signature sequencing.

PubMed

Sánchez-León, Nidia; Arteaga-Vázquez, Mario; Alvarez-Mejía, César; Mendiola-Soto, Javier; Durán-Figueroa, Noé; Rodríguez-Leal, Daniel; Rodríguez-Arévalo, Isaac; García-Campayo, Vicenta; García-Aguilar, Marcelina; Olmedo-Monfil, Vianey; Arteaga-Sánchez, Mario; de la Vega, Octavio Martínez; Nobuta, Kan; Vemaraju, Kalyan; Meyers, Blake C; Vielle-Calzada, Jean-Philippe

2012-06-01

The life cycle of flowering plants alternates between a predominant sporophytic (diploid) and an ephemeral gametophytic (haploid) generation that only occurs in reproductive organs. In Arabidopsis thaliana, the female gametophyte is deeply embedded within the ovule, complicating the study of the genetic and molecular interactions involved in the sporophytic to gametophytic transition. Massively parallel signature sequencing (MPSS) was used to conduct a quantitative large-scale transcriptional analysis of the fully differentiated Arabidopsis ovule prior to fertilization. The expression of 9775 genes was quantified in wild-type ovules, additionally detecting >2200 new transcripts mapping to antisense or intergenic regions. A quantitative comparison of global expression in wild-type and sporocyteless (spl) individuals resulted in 1301 genes showing 25-fold reduced or null activity in ovules lacking a female gametophyte, including those encoding 92 signalling proteins, 75 transcription factors, and 72 RNA-binding proteins not reported in previous studies based on microarray profiling. A combination of independent genetic and molecular strategies confirmed the differential expression of 28 of them, showing that they are either preferentially active in the female gametophyte, or dependent on the presence of a female gametophyte to be expressed in sporophytic cells of the ovule. Among 18 genes encoding pentatricopeptide-repeat proteins (PPRs) that show transcriptional activity in wild-type but not spl ovules, CIHUATEOTL (At4g38150) is specifically expressed in the female gametophyte and necessary for female gametogenesis. These results expand the nature of the transcriptional universe present in the ovule of Arabidopsis, and offer a large-scale quantitative reference of global expression for future genomic and developmental studies.

Growth rate of ovulatory follicles during the first ovulatory oestrus (after seasonal anoestrus) and subsequent oestrous period in Irish Draught mares

PubMed Central

2013-01-01

It is believed that during the spring transition, the developing follicle tends to grow more slowly, persist longer and grow to a larger diameter prior to ovulation than at subsequent oestrus periods. A general suspicion, that the first ovulation of the year is less fertile than subsequent ovulations could be explained by a slower growth rate of the ovulatory follicle during transition with the consequent production of a subfertile oocyte. By detailed serial examination of the same group of Irish Draught mares over three winter/spring periods, no significant difference was found in either growth rate or pre-ovulatory diameter when compared with subsequent ovulations. Mean growth rates over the ten days prior to ovulation were 2.20 mm/day (range 1.18 to 3.64) and 2.19 mm/day (range 1.25 to 3.41) for first and subsequent ovulations respectively. Mean maximum pre-ovulatory diameters were 44.7 mm (range 35 to 59) and 43.5 mm (range 31 to 57.5) for first and subsequent ovulations respectively. The impression gained by practitioners that the first follicle develops more slowly during the transition to the first ovulation of the season may be due to less frequent examinations and consequently a failure to observe and record that follicles may grow and then regress during this period. The largest follicle observed a few days previously is not necessarily the same large follicle found at a later examination. PMID:23497443

Ovule Morphogenesis in Ranunculaceae and its Systematic Significance

PubMed Central

Wang, Zi-Fen; Ren, Yi

2008-01-01

Background and Aims Ranunculaceae has a prominent phylogenetic position in Ranunculales which appears at the base of eudicots. The aims of the present paper are to reveal the features of ovule morphogenesis in different taxa and gain a better understanding of the systematics of Ranunculaceae. Methods Flowers of 17 species from three subfamilies, nine tribes and 16 genera of Ranunculaceae, at successive developmental stages, were collected in the wild and studied with a scanning electron microscope. Key Results The integuments in the unitegmic ovules in Helleborus, Ranunculus and Oxygraphis, as well as the inner integuments in the bitegmic genera, initiate annularly and eventually become cup-shaped. However, the integuments in the unitegmic ovules in Anemone and Clematis, as well as the outer integuments in the bitegmic genera, arise semi-annularly and eventually become hood-shaped. Different kinds of appendages appear on the ovules during development. In Coptis of subfamily Coptidoideae, a wrap-shaped appendage arises outside the ovule and envelopes the ovule entirely. In the genera of subfamily Thalictroideae and tribe Anemoneae of subfamily Ranunculoideae, appendages appear on the placenta, the funicle or both. In tribe Helleboreae of subfamily Ranunculoideae, an alary appendage is initiated where the integument and the funicle join and becomes hood-shaped. Conclusions Ovule morphogenesis characteristics are significant in classification at the levels of subfamilies and tribes. The initiation patterns of the integuments and the development of appendages show diversity in Ranunculaceae. The present observations suggest that the bitegmic, hood-shaped outer integument and endostomic micropyle are primitive while the unitegmic, cupular-shaped outer integument and bistomic micropyle are derivative. PMID:18065776

Role of exogenous estrogen in initiation of estrus and induction of an LH surge

USDA-ARS?s Scientific Manuscript database

Among cattle the LH surge that causes ovulation occurs shortly after the onset of a spontaneous estrus. In addition an injection of 100 'g of GnRH can induce an LH surge capable of inducing ovulation. We hypothesized that different preovulatory estradiol profiles would result in different ovulator...

Makeup and Menstrual Cycle: Near Ovulation, Women Use More Cosmetics

ERIC Educational Resources Information Center

Gueguen, Nicolas

2012-01-01

Research has demonstrated that women near ovulation change their appearance in order to look more attractive. I hypothesized that, near ovulation, women would use more cosmetics. In a first study, female participants received an LH test in a laboratory setting to determine their fertility risk. Participants estimated the time they had spent…

Use of progestagen-gonadotrophin treatments in estrus synchronization of sheep.

PubMed

Boscos, C M; Samartzi, F C; Dellis, S; Rogge, A; Stefanakis, A; Krambovitis, E

2002-10-15

The main objective of this study was to investigate the effectiveness of certain progestagen-gonadotrophin treatments on synchronization of estrus in sheep. In Experiment I, 30 Chios ewes were treated at the beginning of the breeding season with medroxyprogesterone acetate (MAP) intravaginal sponges for 12 days and a single i.m. treatment of either FSH (Group 1,10 IU, n = 8; Group 2, 5 IU, n = 8; Group 3, 2.5 IU, n = 8) or eCG (Group 4, 400 IU, n = 6) at the time of sponge removal. Ten days after sponge removal laparotomy was performed to record ovarian response. Clinical estrus was observed in more (though not at a significant level) FSH treated than eCG treated sheep (62.5% versus 33.3%). Administration of 400 IU eCG resulted in the highest mean number of CL perewe ovulating (2.8 +/- 0.2), with administration of 10 IU FSH producing the next best results (2.1 +/- 0.3). Statistically significant differences in the mean number of CL per ewe ovulating were found only between ewes in Group 3 (1.7 +/- 0.4) and Group 4 (2.8 +/- 0.2) (P < 0.05). In Experiment II, 53 Chios and 30 Berrichon ewes were treated during the mid-breeding season with MAP intravaginal sponges for 12 days and a single i.m. treatment of either 10 IU FSH (27 Chios and 16 Berrichon ewes) or 400 IU eCG (26 Chios and 14 Berrichon ewes), at the time of sponge removal. Ewes that were in estrus on Days 2-4 and 19-23 after sponge removal were mated to fertile rams. No significant differences were recorded between treatment or breed groups in the proportions of ewes observed in estrus after treatment. In the Berrichon breed, FSH administration resulted in higher lambing rates (93.8% versus 57.1%, P < 0.05) and higher mean number of lambs born per ewe exposed to rams (1.4 +/- 0.2 versus 0.8 +/- 0.2, P < 0.05) than that of eCG. After treatment with eCG, the mean number of lambs born per ewe exposed to rams was higher in the Chios than the Berrichon breed (1.4 +/- 0.2 versus 0.8 +/- 0.2, P < 0.05). After treatment with FSH, the lambing rate was higher in the Berrichon than the Chios breed (93.8% versus 63.0%, P < 0.05). In conclusion, a single FSH treatment (5 or 10 IU) at the end of progestagen treatment appears to be more effective than eCG for the induction of synchronized estrus in sheep at the beginning of the breeding season, with no cases of abnormal ovarian response observed. During the mid-breeding season FSH (10 IU) appears to be equally as effective as eCG (400 IU) in respect of lambing rate and mean number of lambs born per ewe.

A Simulation System Based on the Actor Paradigm

DTIC Science & Technology

1988-02-01

of the protocol. Shared memory communication requires the programmer to wait and signal semaphores explicitly to synchronize the communicating parties...wide range of possibilities within the same basic protocol. - The simplicity of the primitive operation set affords those creating new operations...more flexibility (Ada has a large and complicated primitive set). -3- II I I I B A I -I I I I I . 0 1 2 3 4 5 Time 0: Both processes A and B are

Manipulation of follicle development to ensure optimal oocyte quality and conception rates in cattle.

PubMed

Baruselli, P S; Sá Filho, M F; Ferreira, R M; Sales, J N S; Gimenes, L U; Vieira, L M; Mendanha, M F; Bó, G A

2012-08-01

Over the last several decades, a number of therapies have been developed that manipulate ovarian follicle growth to improve oocyte quality and conception rates in cattle. Various strategies have been proposed to improve the responses to reproductive biotechnologies following timed artificial insemination (TAI), superovulation (SOV) or ovum pickup (OPU) programmes. During TAI protocols, final follicular growth and size of the ovulatory follicle are key factors that may significantly influence oocyte quality, ovulation, the uterine environment and consequently pregnancy outcomes. Progesterone concentrations during SOV protocols influence follicular growth, oocyte quality and embryo quality; therefore, several adjustments to SOV protocols have been proposed depending on the animal category and breed. In addition, the success of in vitro embryo production is directly related to the number and quality of cumulus oocyte complexes harvested by OPU. Control of follicle development has a significant impact on the OPU outcome. This article discusses a number of key points related to the manipulation of ovarian follicular growth to maximize oocyte quality and improve conception rates following TAI and embryo transfer of in vivo- and in vitro-derived embryos in cattle. © 2012 Blackwell Verlag GmbH.

Outer synchronization of complex networks with internal delay and coupling delay via aperiodically intermittent pinning control

NASA Astrophysics Data System (ADS)

Zhang, Chuan; Wang, Xingyuan; Wang, Chunpeng; Xia, Zhiqiu

This paper concerns the outer synchronization problem between two complex delayed networks via the method of aperiodically intermittent pinning control. Apart from previous works, internal delay and coupling delay are both involved in this model, and the designed intermittent controllers can be aperiodic. The main work in this paper can be summarized as follows: First, two cases of aperiodically intermittent control with constant gain and adaptive gain are implemented, respectively. The intermittent control and pinning control are combined to reduce consumptions further. Then, based on the Lyapunov stability theory, synchronization protocols are given by strict derivation. Especially, the designed controllers are indeed simple and valid in application of theory to practice. Finally, numerical examples put the proposed control methods to the test.

The in vitro maintenance of clock genes expression within the rat pineal gland under standard and norepinephrine-synchronized stimulation.

PubMed

Andrade-Silva, Jéssica; Cipolla-Neto, José; Peliciari-Garcia, Rodrigo A

2014-01-01

Although the norepinephrine (NE) synchronization protocol was proved to be an important procedure for further modulating in vitro pineal melatonin synthesis, the maintenance of clock genes under the same conditions remained to be investigated. The aim of this study was to investigate the maintenance of the clock genes expression in pineal gland cultures under standard and NE-synchronized stimulation. The glands were separated into three experimental groups: Control, Standard (acute NE-stimulation), and NE-synchronized. The expression of Bmal1, Per2, Cry2, Rev-erbα, the clock controlled gene Dbp and Arylalkylamine-N-acetyltransferase were investigated, as well as melatonin content. No oscillations were observed in the expression of the investigated genes from the control group. Under Standard NE stimulation, the clock genes did not exhibit a rhythmic pattern of expression. However, in the NE-synchronized condition, a rhythmic expression pattern was observed in all cases. An enhancement in pineal gland responsiveness to NE stimulation, reflected in an advanced synthesis of melatonin was also observed. Our results reinforce our previous hypothesis that NE synchronization of pineal gland culture mimics the natural rhythmic release of NE in the gland, increasing melatonin synthesis and keeping the pineal circadian clock synchronized, ensuring the fine adjustments that are relied in the clockwork machinery. Copyright © 2014 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

Ovarian follicle maturation and ovulation: An integrated perspective

USGS Publications Warehouse

Patino, R.; Thomas, P.; Yoshizaki, G.

2003-01-01

Numerous studies with teleosts have addressed the regulation and mechanisms of oocyte maturation, but largely at the exclusion of ovulation. A smaller but still considerable number of studies have focused on ovulation, and ignored maturation. Consequently, little is known about the mechanistic linkages between these two events. New information is presented here indicating that luteinizing hormone regulates the acquisition not only of oocyte maturational competence, but also ovulatory competence. The thesis is presented that maturation and ovulation are closely integrated and overlapping events that are best viewed conceptually and experimentally as parts of a functional whole. ?? 2004 Kluwer Academic Publishers.

Functional analysis of sporophytic transcripts repressed by the female gametophyte in the ovule of Arabidopsis thaliana.

PubMed

Armenta-Medina, Alma; Huanca-Mamani, Wilson; Sanchez-León, Nidia; Rodríguez-Arévalo, Isaac; Vielle-Calzada, Jean-Philippe

2013-01-01

To investigate the genetic and molecular regulation that the female gametophyte could exert over neighboring sporophytic regions of the ovule, we performed a quantitative comparison of global expression in wild-type and nozzle/sporocyteless (spl) ovules of Arabidopsis thaliana (Arabidopsis), using Massively Parallel Signature Sequencing (MPSS). This comparison resulted in 1517 genes showing at least 3-fold increased expression in ovules lacking a female gametophyte, including those encoding 89 transcription factors, 50 kinases, 25 proteins containing a RNA-recognition motif (RRM), and 20 WD40 repeat proteins. We confirmed that eleven of these genes are either preferentially expressed or exclusive of spl ovules lacking a female gametophyte as compared to wild-type, and showed that six are also upregulated in determinant infertile1 (dif1), a meiotic mutant affected in a REC8-like cohesin that is also devoided of female gametophytes. The sporophytic misexpression of IOREMPTE, a WD40/transducin repeat gene that is preferentially expressed in the L1 layer of spl ovules, caused the arrest of female gametogenesis after differentiation of a functional megaspore. Our results show that in Arabidopsis, the sporophytic-gametophytic cross talk includes a negative regulation of the female gametophyte over specific genes that are detrimental for its growth and development, demonstrating its potential to exert a repressive control over neighboring regions in the ovule.

Ovarian activity and safety of a novel levonorgestrel/ethinyl estradiol continuous oral contraceptive regimen.

PubMed

Archer, David F; Kovalevsky, George; Ballagh, Susan A; Grubb, Gary S

2009-09-01

A continuous regimen of oral levonorgestrel (LNG) 90 mcg/ethinyl estradiol (EE) 20 mcg was evaluated for inhibition of ovulation, time to return to ovulation after stopping treatment and safety. This open-label study was conducted in healthy women aged 18-35 years. Ovulation was documented before treatment, and then participants received oral tablets containing LNG 90 mcg/EE 20 mcg to be taken continuously for three 28-day intervals. Ovarian activity was assessed three times per week during the treatment period with transvaginal ultrasound scans and measurements of serum 17beta-estradiol, progesterone, follicle-stimulating hormone and luteinizing hormone concentrations. Safety assessments included physical examinations, laboratory evaluations and adverse event records. Thirty-seven of the 58 subjects who received treatment met predefined criteria for efficacy analysis. No on-treatment ovulations occurred in the efficacy or intent-to-treat population. There was evidence of ovulation within 37 days of stopping treatment for 46 (98%) of 47 subjects evaluated posttreatment. The final subject with a history of polycystic ovarian syndrome ovulated by Day 66. The safety profile observed during this 84-day continuous regimen was similar to that seen with other low-dose oral contraceptives administered in a cyclic regimen. The continuous LNG/EE regimen completely inhibited ovulation, with little evidence of follicular development and with rapid return of ovulatory capacity after stopping treatment.

Determinants of embryo development and quality in beef cattle: Effect of pre-ovulatory follicle size, CL volume, and serum concentrations of progesterone

USDA-ARS?s Scientific Manuscript database

Previous research indicates cows ovulating a small dominant follicle (<_ 12 mm) had lower pregnancy rates than cows ovulating a large follicle (> 12 mm). We hypothesized cows ovulating a small follicle would have delayed embryo development and decreased embryo quality. Objectives of this study wer...

Oviposition strategies of conifer seed chalcids in relation to host phenology.

PubMed

Rouault, Gaëlle; Turgeon, Jean; Candau, Jean-Noël; Roques, Alain; von Aderkas, Patrick

2004-10-01

Insects are considered the most important predators of seed cones, the female reproductive structures of conifers, prior to seed dispersal. Slightly more than 100 genera of insects are known to parasitize conifer seed cones. The most diverse (i.e., number of species) of these genera is Megastigmus (Hymenoptera: Torymidae), which comprises many important seed pests of native and exotic conifers. Seed chalcids, Megastigmus spp., lay eggs inside the developing ovules of host conifers and, until recently, oviposition was believed to occur only in fertilized ovules. Ovule development begins just after pollination, but stops if cells are not fertilized. The morphological stage of cone development at the time of oviposition by seed chalcids has been established for many species; however, knowledge of ovule development at that time has been documented for only one species, M. spermotrophus. Megastigmus spermotrophus oviposits in Douglas-fir ovules after pollination but before fertilization. Unlike the unfertilized ovules, those containing a M. spermotrophus larva continue to develop, whether fertilized or not, stressing the need to broaden our understanding of the insect-plant interactions for this entire genus. To achieve this task, we reviewed the scientific literature and assembled information pertaining to the timing of oviposition and to the pollination and fertilization periods of their respective host(s). More specifically, we were searching for circumstantial evidence that other species of Megastigmus associated with conifers could behave (i.e., oviposit before ovule fertilization) and impact on female gametophyte (i.e., prevent abortion) like M. spermotrophus. The evidence from our compilation suggests that seed chalcids infesting Pinaceae may also oviposit before ovule fertilization, just like M. spermotrophus, whereas those infesting Cupressaceae seemingly oviposit after ovule fertilization. Based on this evidence, we hypothesize that all species of Megastigmus associated with Pinaceae can oviposit in unfertilized ovules, whereas those exploiting Cupressaceae cannot, and thus oviposit only in already fully developed fertilized seeds. Furthermore, we predict that the presence of a larva in unfertilized ovules of all Pinaceae will influence the development of the female gametophyte by preventing its abortion. This influence on the Pinaceae can be interpreted as an ability to parasitize any of the potential seeds present in a seed cone, and as such represents a much more efficient oviposition strategy than searching and locating only fertilized seeds. Concomitantly, this ability has likely led to an overestimation of the impact of the species of seed chalcid infesting Pinaceae on seed production.

Oviposition strategies of conifer seed chalcids in relation to host phenology

NASA Astrophysics Data System (ADS)

Rouault, Gaëlle; Turgeon, Jean; Candau, Jean-Noël; Roques, Alain; Aderkas, Patrick

2004-10-01

Insects are considered the most important predators of seed cones, the female reproductive structures of conifers, prior to seed dispersal. Slightly more than 100 genera of insects are known to parasitize conifer seed cones. The most diverse (i.e., number of species) of these genera is Megastigmus (Hymenoptera: Torymidae), which comprises many important seed pests of native and exotic conifers. Seed chalcids, Megastigmus spp., lay eggs inside the developing ovules of host conifers and, until recently, oviposition was believed to occur only in fertilized ovules. Ovule development begins just after pollination, but stops if cells are not fertilized. The morphological stage of cone development at the time of oviposition by seed chalcids has been established for many species; however, knowledge of ovule development at that time has been documented for only one species, M. spermotrophus. Megastigmus spermotrophus oviposits in Douglas-fir ovules after pollination but before fertilization. Unlike the unfertilized ovules, those containing a M. spermotrophus larva continue to develop, whether fertilized or not, stressing the need to broaden our understanding of the insect plant interactions for this entire genus. To achieve this task, we reviewed the scientific literature and assembled information pertaining to the timing of oviposition and to the pollination and fertilization periods of their respective host(s). More specifically, we were searching for circumstantial evidence that other species of Megastigmus associated with conifers could behave (i.e., oviposit before ovule fertilization) and impact on female gametophyte (i.e., prevent abortion) like M. spermotrophus. The evidence from our compilation suggests that seed chalcids infesting Pinaceae may also oviposit before ovule fertilization, just like M. spermotrophus, whereas those infesting Cupressaceae seemingly oviposit after ovule fertilization. Based on this evidence, we hypothesize that all species of Megastigmus associated with Pinaceae can oviposit in unfertilized ovules, whereas those exploiting Cupressaceae cannot, and thus oviposit only in already fully developed fertilized seeds. Furthermore, we predict that the presence of a larva in unfertilized ovules of all Pinaceae will influence the development of the female gametophyte by preventing its abortion. This influence on the Pinaceae can be interpreted as an ability to parasitize any of the potential seeds present in a seed cone, and as such represents a much more efficient oviposition strategy than searching and locating only fertilized seeds. Concomitantly, this ability has likely led to an overestimation of the impact of the species of seed chalcid infesting Pinaceae on seed production.

A New On-Line Diagnosis Protocol for the SPIDER Family of Byzantine Fault Tolerant Architectures

NASA Technical Reports Server (NTRS)

Geser, Alfons; Miner, Paul S.

2004-01-01

This paper presents the formal verification of a new protocol for online distributed diagnosis for the SPIDER family of architectures. An instance of the Scalable Processor-Independent Design for Electromagnetic Resilience (SPIDER) architecture consists of a collection of processing elements communicating over a Reliable Optical Bus (ROBUS). The ROBUS is a specialized fault-tolerant device that guarantees Interactive Consistency, Distributed Diagnosis (Group Membership), and Synchronization in the presence of a bounded number of physical faults. Formal verification of the original SPIDER diagnosis protocol provided a detailed understanding that led to the discovery of a significantly more efficient protocol. The original protocol was adapted from the formally verified protocol used in the MAFT architecture. It required O(N) message exchanges per defendant to correctly diagnose failures in a system with N nodes. The new protocol achieves the same diagnostic fidelity, but only requires O(1) exchanges per defendant. This paper presents this new diagnosis protocol and a formal proof of its correctness using PVS.

Ovulation induced by mucosa vaginal absorption of buserelin and triptorelin in rabbit.

PubMed

Viudes-de-Castro, M P; Lavara, R; Marco-Jiménez, F; Cortell, C; Vicente, J S

2007-10-15

The aim of this study was to evaluate the supplementation of semen extender with two synthetic GnRH analogues (buserelin and triptorelin) to induce ovulation in rabbit does submitted to artificial insemination. In a first experiment, 255 receptive multiparous does were inseminated with 0.5 mL of Tris-citrate-glucose extender supplemented or not with two GnRH synthetic analogues. Experimental groups were: NC (not supplemented extender), PC (not supplemented extender and does treated with 1 microg of buserelin i.m.), B2 (2 microg per female buserelin supplemented extender), B5 (5 microg per female buserelin supplemented extender), T2 (2 microg per female triptorelin supplemented extender) and T5 (5 microg per female triptorelin supplemented extender). Thirteen does of NC females ovulated, reaching an ovulation rate similar to the other groups. Ovulation rate was similar in all groups (11.4-12.5). The efficiency of ovulation induction was very low (32.5%) in NC group and showed the higher results in PC females (97.8%). Only B5 females reached similar ovulation induction response than PC group. In a second experiment, 702 receptive does were inseminated to compare fertility and prolificacy parameters from the conventional insemination technique (control group, females treated with 1 microg per female of buserelin intramuscularly) versus a supplementation with buserelin or triptorelin (5 microg per female) in semen extender (B5 and T5 groups, respectively). Fertility and prolificacy parameters were similar among the groups (77.8% fertility rate, 73.9% kindling rate, 9.4 live born and 9.9 total born). This study demonstrate the possibility of ovulation induction in rabbits by adding two GnRH synthetic analogues in the seminal doses and open up new prospects for changing rabbit insemination procedures.

In vivo imaging in the rabbit as a model for the study of ovulation-inducing factors.

PubMed

Cervantes, M P; Palomino, J M; Adams, G P

2015-01-01

The study of factors responsible for eliciting ovulation in rabbits has been hampered by the lack of a suitable method of monitoring the ovaries in vivo. Ovarian imaging by ultrasound biomicroscopy was used in two experiments designed to determine the effects of seminal plasma on the ovulatory response in rabbits. In Experiment 1, female rabbits were group-housed and treated intramuscularly with saline, gonadotropin releasing hormone (GnRH), or seminal plasma of llamas or rabbits (n = 4 to 6 per group). Rabbits were euthanized eight days later to evaluate the ovarian response by ultrasound biomicroscopy ex situ. No differences among groups were detected in the proportion of rabbits that ovulated or in the number and size of corpora lutea. The high incidence of ovulation in the negative control group was unexpected, and confounded determination of an ovulation-inducing effect of seminal plasma. In Experiment 2, female rabbits were caged individually, and treated as in Experiment 1 (n = 5 to 7 per group). The ovarian response was evaluated in vivo by transcutaneous ultrasound biomicroscopy. Ovulation and formation of corpora lutea were detected only in rabbits given GnRH. A preovulatory surge in plasma luteinizing hormone concentration and a post-ovulatory rise in plasma progesterone concentration were detected only in rabbits treated with GnRH. Surgical translocation of the ovaries to a subcutaneous position enabled longitudinal assessment of the ovulatory response by ultrasound biomicroscopy. Results clearly documented the effect of physical/social interaction on ovulation in rabbits, and did not support the hypothesis that seminal plasma elicits ovulation in rabbits. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Effects of immunization against bone morphogenetic protein-15 and growth differentiation factor-9 on ovarian function in mares.

PubMed

Davis, Kelli A; Klohonatz, Kristin M; Mora, Darcy S O; Twenter, Hannah M; Graham, Peter E; Pinedo, Pablo; Eckery, Douglas C; Bruemmer, Jason E

2018-05-01

Currently there is no contraceptive vaccine that can cause permanent sterility in mares. This study investigates the effect of vaccination against oocyte-specific growth factors, Bone Morphogenetic Protein 15 (BMP-15) and Growth Differentiation Factor 9 (GDF-9), on ovarian function of mares. It was hypothesized that immunization against these growth factors would prevent ovulation and/or accelerate depletion of the oocyte reserve. For this study, 30 mares were randomly assigned to three groups (n = 10/group) and vaccinated with BMP-15 or GDF-9 peptides conjugated to KLH and adjuvant, or a control of phosphate buffered saline and adjuvant. Horses received vaccinations at weeks 0, 6, 12, and 18. Ovarian activity and estrous behavior were evaluated 3 days a week via ultrasonography and interaction with a stallion. The study was initiated on March1, 2016. Upon evaluation of ovulation rate, the GDF-9 group did not have a difference (P = 0.66) in ovulation rate when compared to controls (10.8 and 10.0 ovulations, respectively), but the number of ovulations in the BMP-15 group was less (P = 0.02; 4.9 ovulations). Average follicle size prior to ovulation was less (P < 0.0001) in both treatment groups compared to controls. Estrous behavior was altered in both the BMP-15 and GDF-9 groups compared to controls after the second vaccination (P = 0.05 and 0.03, respectively). Although further research is required to determine the continued effects of vaccination against GDF-9 on ovulation rates, these results indicate that vaccination against BMP-15 and GDF-9 could serve as a contraceptive in wild horse populations. Copyright © 2018 Elsevier B.V. All rights reserved.

Effect of follicular aspiration just before ovulation on corpus luteum characteristics, circulating progesterone concentrations and uterine receptivity in single-ovulating and superstimulated heifers.

PubMed

O'Hara, L; Scully, S; Maillo, V; Kelly, A K; Duffy, P; Carter, F; Forde, N; Rizos, D; Lonergan, P

2012-05-01

The aim of this study was to investigate, in unstimulated and superstimulated heifers, the effect of follicle aspiration just before ovulation on corpus luteum (CL) development, circulating progesterone (P(4)) concentrations and the ability of the uterus to support embryo development. Following follicle aspiration or ovulation timed from GNRH administration, CL development was assessed by daily ultrasonography, and CL function was assessed in terms of the capacity to produce P(4) and the expression of genes involved in steroidogenesis in luteal tissue. The capacity of the uterine environment to support conceptus development was assessed following transfer and recovery of in vitro-produced embryos. Follicular aspiration just before the expected time of ovulation leads to a significant reduction in CL diameter, CL area and area of luteal tissue. This was associated with a decrease in circulating P(4) in both unstimulated and superstimulated heifers. Follicle aspiration leads to a reduction in conceptus length and area on day 14 in unstimulated heifers only. Follicle aspiration leads to a reduction in the expression of LHCGR in luteal tissue from unstimulated heifers compared with those in which the CL formed after ovulation. Superstimulation significantly reduced the expression of STAR in luteal tissue in both ovulated and follicle-aspirated heifers. In conclusion, in stimulated and unstimulated heifers, aspiration of the preovulatory dominant follicle(s) just before expected ovulation interferes with the subsequent formation and function of the CL, in terms of size and P(4) output and this, in turn, is associated with a reduced capacity of the uterus to support conceptus elongation in unstimulated heifers.

Maitake mushroom (Grifola frondosa) extract induces ovulation in patients with polycystic ovary syndrome: a possible monotherapy and a combination therapy after failure with first-line clomiphene citrate.

PubMed

Chen, Jui-Tung; Tominaga, Kunihiko; Sato, Yoshiaki; Anzai, Hideo; Matsuoka, Ryo

2010-12-01

Insulin resistance is a prominent feature of polycystic ovary syndrome (PCOS), and insulin-sensitizing drugs are used to induce ovulation. Recently, it was reported that an extract from Maitake mushroom (Grifola frondosa) improves insulin resistance. The objective was to explore the effects of Maitake extract (SX-fraction: MSX) to induce ovulation in patients with PCOS in comparison with and in combination with clomiphene citrate (CC). We conducted an open trial with 80 patients with PCOS at three clinics in Japan. Seventy-two (72) new patients were randomly assigned to receive MSX or CC monotherapy for up to 12 weeks. Eighteen (18) patients who did not respond to MSX or CC were subjected to combination therapy of MSX and CC for up to 16 weeks. Eight (8) patients with documented history of failure to CC received combination therapy from the beginning. Ovulation was assessed by ultrasonography. Twenty-six (26) patients in the MSX group and 31 in the CC group were evaluated for ovulation. The ovulation rates for MSX and CC were as follows: 76.9% (20/26) and 93.5% (29/31), respectively by the patients (NS), and 41.7% (30/72) and 69.9% (58/83), respectively, by the cycles (p = 0.0006). In the combination therapy, 7 of 7 patients who failed in MSX monotherapy and 6 of 8 patients who failed in CC monotherapy showed ovulation. The present study suggests that MSX alone may induce ovulation in PCOS patients and may be useful as an adjunct therapy for patients who failed first-line CC treatment.

Understanding the cone scale in Cupressaceae: insights from seed-cone teratology in Glyptostrobus pensilis.

PubMed

Dörken, Veit Martin; Rudall, Paula J

2018-01-01

Both wild-type and teratological seed cones are described in the monoecious conifer Glyptostrobus pensilis and compared with those of other Cupressaceae sensu lato and other conifers. Some Cupressaceae apparently possess a proliferation of axillary structures in their cone scales. In our interpretation, in Glyptostrobus each bract of both typical and atypical seed cones bears two descending accessory shoots, interpreted here as seed scales (ovuliferous scales). The primary seed scale is fertile and forms the ovules, the second is sterile and forms characteristic tooth-like structures. The bract and the two axillary seed scales are each supplied with a single distinct vascular bundle that enters the cone axis as a separate strand; this vasculature also characterises the descending accessory short shoots in the vegetative parts of the crown. In wild-type seed cones, the fertile seed scale is reduced to its ovules, and the ovules are always axillary. In contrast, the ovules of some of the teratological seed cones examined were located at the centre of the cone scale. An additional tissue found on the upper surface of the sterile lower seed scale is here interpreted as the axis of the fertile seed scale. Thus, the central position of the ovules can be explained by recaulescent fusion of the upper fertile and lower sterile seed scales. In several teratological cone scales, the ovules were enveloped by an additional sterile tissue that is uniseriate and represents an epidermal outgrowth of the fertile seed scale. Close to the ovules, the epidermis was detached from lower tissue and surrounded the ovule completely, except at the micropyle. These teratological features are potentially significant in understanding seed-cone homologies among extant conifers.

Ovulation induction in normogonadotropic anovulation (PCOS).

PubMed

van Santbrink, Evert J P; Fauser, Bart C J M

2006-06-01

Treatment of normogonadotropic anovulatory infertility (World Health Organization class 2, or WHO2) is by induction of ovulation using clomiphene citrate (CC), followed by follicle-stimulating hormone (FSH) in cases of treatment failure. Not all patients will become ovulatory or will conceive with this treatment. Others, exhibiting multifollicular instead of monofollicular development, may encounter complications such as ovarian hyperstimulation and multiple pregnancy. Recently introduced alternative treatment interventions-such as insulin-sensitizing drugs, aromatase inhibitors, or laparoscopic electrocautery of the ovaries-may offer the possibility of improving the efficacy of the classical ovulation induction algorithm. Based on initial patient characteristics, it may be possible to identify specific patient subgroups with altered chances of success or complications while using one of these interventions. Regarding CC and FSH ovulation induction, this has been performed using multivariate prediction models. This approach may enable us to improve safety, cost-effectiveness, and patient convenience in future ovulation induction.

Candidate gene identification of ovulation-inducing genes by RNA sequencing with an in vivo assay in zebrafish.

PubMed

Klangnurak, Wanlada; Fukuyo, Taketo; Rezanujjaman, M D; Seki, Masahide; Sugano, Sumio; Suzuki, Yutaka; Tokumoto, Toshinobu

2018-01-01

We previously reported the microarray-based selection of three ovulation-related genes in zebrafish. We used a different selection method in this study, RNA sequencing analysis. An additional eight up-regulated candidates were found as specifically up-regulated genes in ovulation-induced samples. Changes in gene expression were confirmed by qPCR analysis. Furthermore, up-regulation prior to ovulation during natural spawning was verified in samples from natural pairing. Gene knock-out zebrafish strains of one of the candidates, the starmaker gene (stm), were established by CRISPR genome editing techniques. Unexpectedly, homozygous mutants were fertile and could spawn eggs. However, a high percentage of unfertilized eggs and abnormal embryos were produced from these homozygous females. The results suggest that the stm gene is necessary for fertilization. In this study, we selected additional ovulation-inducing candidate genes, and a novel function of the stm gene was investigated.

Sin1, a Mutation Affecting Female Fertility in Arabidopsis, Interacts with Mod1, Its Recessive Modifier

PubMed Central

Lang, J. D.; Ray, S.; Ray, A.

1994-01-01

In Arabidopsis thaliana, a mutation in the SIN1 gene causes aberrant ovule development and female-specific sterility. The effect of the sin1 mutation is polymorphic and pleiotropic in different genetic backgrounds. The polymorphism concerns morphology of the mutant ovules. The pleiotropism involves internodal distance and inflorescence initiation time. The particular ovule phenotype and the length of internodes are dependent on an interaction of sin1 with a second recessive gene, which we term mod1. The recessive mod1 allele in a homozygous sin1 mutant plant reduces internode length and ovule integument size. The mutation sin1, but not mod1, has a demonstrable effect on ovule morphology when acting idependently. In our crosses mod1 was inseparably linked to the well known mutation erecta that is known to cause a reduction in internode and pedicel lengths. PMID:7982564

Evaluation of gene expression in pigs selected for enhanced reproduction using differential display PCR: II. Anterior pituitary.

PubMed

Bertani, G R; Gladney, C D; Johnson, R K; Pomp, D

2004-01-01

The objective of this study was to identify differentially expressed genes in the anterior pituitary (AP) of sows selected for enhanced reproductive phenotypes. Selection in the Index (I) line was based on an index of ovulation rate and embryo survival, whereas random selection was used in the Control (C) line. Average numbers of fully formed piglets at birth were 12.5 +/- 1.5 and 9.9 +/- 2.0 for Line I and C sows used in this study, respectively. In order to induce luteolysis and synchronize follicle development, sows were injected (i.m.) with 2 mL of prostaglandin F2alpha analog between d 12 and 14 of the estrous cycle. Tissue was harvested 2 d (d2) or 4 d (d4) after injection, resulting in four experimental groups: Cd2 (n = 6), Cd4 (n = 4), Id2 (n = 6), and Id4 (n = 7). Differential display PCR (ddPCR) was used to search for transcriptional changes between selection lines in the AP, using samples within line but pooled across days. Northern hybridization was used to confirm ddPCR results. For ddPCR, two pools were used from each line (C and I). Three genes were confirmed to be differentially expressed between Lines I and C: G-beta like protein, ferritin heavy-chain, and follicle stimulating hormone beta subunit, whereas many other expressed sequence tags were observed to be differentially expressed but still require confirmation. Our findings indicate that long-term selection to increase ovulation rate and decrease embryo mortality has altered transcriptional patterns in the anterior pituitary, most likely as correlated responses.

Effect of restricted suckling on the onset of follicular dynamics and body condition score in Brahman cattle raised under tropical conditions.

PubMed

Mondragón, Violeta; Galina, Carlos S; Rubio, Ivette; Corro, Manuel; Salmerón, Frida

2016-04-01

With the aim of evaluating the effect of restricted suckling on the onset of follicular dynamics and body condition, multiparous Bos indicus cows were distributed in two groups. One group (RS=36) was subjected to a scheme of restricted suckling starting at 21 days postpartum. Calves were allowed to suckle once per day for a period of two h whilst the control group (C=18) remained with their dams at all times. At calving, body condition score, back fat thickness and body weight had similar values (p>0.05) for both groups. By day 85 postpartum both groups had recorded losses in body weight. The cows in the continuous group formed a greater (p<0.05) number of follicles of class size <6mm in both periods before and after synchronization. The proportion of cows showing estrus and ovulation before 45 days, was not different (p>0.05). The number of cows that exhibited estrus after 45 days, was greater (p<0.05) in RS than C group, 72.2% and 55.5%, respectively. Same situation (p<0.05) occurred in cows that ovulated, 88.8 and 66.7%, for groups RS and C, respectively. The subset in the intensive observations showed that the size of the bigger follicle was larger (p<0.05) for RS cows than C cows from 36 h after CIDR withdrawal. At 57 h, the size of the biggest follicle recorded was not different between groups (p>0.05). A regime of restricted suckling favors the earlier growth of follicles and the prompt restoration of ovarian activity. Copyright © 2016 Elsevier B.V. All rights reserved.

Climatic factors affecting quantity and quality grade of in vivo derived embryos of cattle.

PubMed

Chinchilla-Vargas, Josué; Jahnke, Marianna M; Dohlman, Tyler M; Rothschild, Max F; Gunn, Patrick J

2018-05-01

The present study investigated the effects of climatic variables on the quality grade and quantity of in vivo derived cattle embryos in the Midwestern United States. Climatic information included greatest and least daily temperature, average daily wind speed and average temperature-humidity index for each of the 765 records. The response variables included the number of ovarian structures, viable embryos, quality grade 1 embryos, quality grade 2 embryos, quality grade 3 embryos, freezable embryos (sum of quality grade 1 and quality grade 2 embryos), transferable embryos (sum of quality grade 1-3 embryos), degenerate embryos and unfertilized ova. Measures for variables among the breeds of donors and sires grouped by geographical origin were compared. A negative effect of greater temperatures during the early embryonic development stage tended (P < 0.10) to be associated with a decrease in the quality of embryos recovered. Interestingly, the greater the Temperature-Humidity Index (THI) during the early ovarian antral follicular development stage 40-45 days prior to ovulation was associated with a tendency for greater numbers of total number of freezable and transferable embryos recovered per uterine flushing (P < 0.10). Increased wind speed at the early antral follicular phase 40-45 days prior to ovulation was associated with an increase in the percentage of quality grade 1 embryos recovered (P < 0.05). Wind speed during the estrous synchronization period was also associated with a lesser number of embryos recovered (P < 0.05). This retrospective study confirms that climatic variables have significant effects on the in vivo production of cattle embryos and that wind speed should be considered in future analyses of factors affecting embryo quality. Copyright © 2018 Elsevier B.V. All rights reserved.

[Clinical outcomes and economic analysis of two ovulation induction protocols in patients undergoing repeated IVF/ICSI cycles].

PubMed

Chen, Xiao; Geng, Ling; Li, Hong

2014-04-01

To compare the clinical outcomes and cost-effectiveness of luteal phase down-regulation with gonadotrophin-releasing hormone (GnRH) agonist protocol and GnRH antagonist protocol in patients undergoing repeated in vitro fertilization and intracytoplasmic sperm injection (IVF-ICSI) cycles. A retrospective analysis of clinical outcomes and costs was conducted among 198 patients undergoing repeated IVF-ICSI cycles, including 109 receiving luteal phase down-regulation with GnRH agonist protocol (group A) and 89 receiving GnRH antagonist protocol (group B). The numbers of oocytes retrieved and good embryos, clinical pregnancy rate, abortion rate, the live birth rate, mean total cost, and the cost-effective ratio were compared between the two groups. In patients undergoing repeated IVF-ICSI cycles, the two protocols produced no significant differences in the number of good embryos, clinical pregnancy rate, abortion rate, or twin pregnancy rate. Compared with group B, group A had better clinical outcomes though this difference was not statistically significant. The number of retrieved oocytes was significantly greater and live birth rate significantly higher in group A than in group B (9.13=4.98 vs 7.11=4.74, and 20.2% vs 9.0%, respectively). Compared with group B, group A had higher mean total cost per cycle but lower costs for each oocyte retrieved (2729.11 vs 3038.60 RMB yuan), each good embryo (8867.19 vs 9644.85 RMB yuan), each clinical pregnancy (77598.06 vs 96139.85 RMB yuan). For patients undergoing repeated IVF/ICSI cycle, luteal phase down-regulation with GnRH agonist protocol produces good clinical outcomes with also good cost-effectiveness in spite an unsatisfactory ovarian reserve.

Effect of Exercise on Ovulation: A Systematic Review.

PubMed

Hakimi, Osnat; Cameron, Luiz-Claudio

2017-08-01

Infertility has been described as a devastating life crisis for couples, and has a particularly severe effect on women, in terms of anxiety and depression. Anovulation accounts for around 30% of female infertility, and while lifestyle factors such as physical activity are known to be important, the relationship between exercise and ovulation is multi-factorial and complex, and to date there are no clear recommendations concerning exercise regimes. The objective of this review was to systematically assess the effect of physical activity on ovulation and to discuss the possible mechanisms by which exercise acts to modulate ovulation in reproductive-age women. This was done with a view to improve existing guidelines for women wishing to conceive, as well as women suffering from anovulatory infertility. The published literature was searched up to April 2016 using the search terms ovulation, anovulatory, fertility, sport, physical activity and exercise. Both observational and interventional studies were considered, as well as studies that combined exercise with diet. Case studies and articles that did not report anovulation/ovulation or ovarian morphology as outcomes were excluded. Studies involving administered drugs in addition to exercise were excluded. In total, ten interventions and four observational cohort studies were deemed relevant. Cohort studies showed that there is an increased risk of anovulation in extremely heavy exercisers (>60 min/day), but vigorous exercise of 30-60 min/day was associated with reduced risk of anovulatory infertility. Ten interventions were identified, and of these three have studied the effect of vigorous exercise on ovulation in healthy, ovulating women, but only one showed a significant disruption of ovulation as a result. Seven studies have investigated the effect of exercise on overweight/obese women suffering from polycystic ovary syndrome (PCOS) or anovulatory infertility, showing that exercise, with or without diet, can lead to resumption of ovulation. The mechanism by which exercise affects ovulation is most probably via modulation of the hypothalamic-pituitary-gonadal (HPG) axis due to increased activity of the hypothalamic-pituitary-adrenal (HPA) axis. In heavy exercisers and/or underweight women, an energy drain, low leptin and fluctuating opioids caused by excess exercise have been implicated in HPA dysfunction. In overweight and obese women (with or without PCOS), exercise contributed to lower insulin and free androgen levels, leading to the restoration of HPA regulation of ovulation. Several clear gaps have been identified in the existing literature. Short-term studies of over-training have not always produced the disturbance to ovulation identified in the observational studies, bringing up the question of the roles of longer term training and chronic energy deficit. We believe this merits further investigation in specific cohorts, such as professional athletes. Another gap is the complete absence of exercise-based interventions in anovulatory women with a normal body mass index (BMI). The possibly unjustified focus on weight loss rather than the exercise programme means there is also a lack of studies comparing types of physical activity, intensity and settings. We believe that these gaps are delaying an efficient and effective use of exercise as a therapeutic modality to treat anovulatory infertility.

IEEE 1588 Time Synchronization Board in MTCA.4 Form Factor

NASA Astrophysics Data System (ADS)

Jabłoński, G.; Makowski, D.; Mielczarek, A.; Orlikowski, M.; Perek, P.; Napieralski, A.; Makijarvi, P.; Simrock, S.

2015-06-01

Distributed data acquisition and control systems in large-scale scientific experiments, like e.g. ITER, require time synchronization with nanosecond precision. A protocol commonly used for that purpose is the Precise Timing Protocol (PTP), also known as IEEE 1588 standard. It uses the standard Ethernet signalling and protocols and allows obtaining timing accuracy of the order of tens of nanoseconds. The MTCA.4 is gradually becoming the platform of choice for building such systems. Currently there is no commercially available implementation of the PTP receiver on that platform. In this paper, we present a module in the MTCA.4 form factor supporting this standard. The module may be used as a timing receiver providing reference clocks in an MTCA.4 chassis, generating a Pulse Per Second (PPS) signal and allowing generation of triggers and timestamping of events on 8 configurable backplane lines and two front panel connectors. The module is based on the Xilinx Spartan 6 FPGA and thermally stabilized Voltage Controlled Oscillator controlled by the digital-to-analog converter. The board supports standalone operation, without the support from the host operating system, as the entire control algorithm is run on a Microblaze CPU implemented in the FPGA. The software support for the card includes the low-level API in the form of Linux driver, user-mode library, high-level API: ITER Nominal Device Support and EPICS IOC. The device has been tested in the ITER timing distribution network (TCN) with three cascaded PTP-enabled Hirschmann switches and a GPS reference clock source. An RMS synchronization accuracy, measured by direct comparison of the PPS signals, better than 20 ns has been obtained.

Comparison of acupuncture pretreatment followed by letrozole versus letrozole alone on live birth in anovulatory infertile women with polycystic ovary syndrome: a study protocol for a randomised controlled trial.

PubMed

Li, Juan; Ng, Ernest Hung Yu; Stener-Victorin, Elisabet; Hu, Zhenxing; Wu, Wanting; Lai, Maohua; Wu, Taixiang; Ma, Hongxia

2016-10-07

The high prevalence of insulin resistance in women with polycystic ovary syndrome (PCOS) is considered to be one of the major pathophysiological changes in PCOS that leads to anovulatory infertility. We hypothesise that electroacupuncture pretreatment improves insulin sensitivity and leads to a higher ovulation rate and greater chances of live birth after the induction of ovulation. The effect of electroacupuncture pretreatment followed by ovulation induction in women with anovulatory PCOS has not been investigated before, and we present here a randomised controlled trial to test this hypothesis by comparing electroacupuncture pretreatment followed by letrozole versus letrozole alone in anovulatory women with PCOS. This is a multicentre, randomised,and controlled trial. A total of 384 patients will be enrolled in this study and will be randomly allocated by a central randomisation system to the treatment group or the control group in a 1:1 ratio. The treatment group will undergo 16 weeks of electroacupuncture pretreatment followed by 4 cycles of letrozole, and the control group will only undergo 4 cycles of letrozole. The primary outcome will be the live birth rate. All statistical analyses will be performed using the SPSS program V.21.0 (SPSS, Chicago, Illinois, USA), and a p value <0.05 will be considered statistically significant. This study has been approved by the ethics committees of each participating centre. Written consent will be obtained from each patient and her husband before any study procedure is performed. Adverse events will be categorised, and the percentage of patients experiencing adverse events or serious adverse events during the treatment period will be documented. The results of this trial will be disseminated in peer-reviewed journals and presented at international meetings. NCT02491320. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Comparison of acupuncture pretreatment followed by letrozole versus letrozole alone on live birth in anovulatory infertile women with polycystic ovary syndrome: a study protocol for a randomised controlled trial

PubMed Central

Li, Juan; Ng, Ernest Hung Yu; Stener-Victorin, Elisabet; Hu, Zhenxing; Wu, Wanting; Lai, Maohua; Wu, Taixiang; Ma, Hongxia

2016-01-01

Introduction The high prevalence of insulin resistance in women with polycystic ovary syndrome (PCOS) is considered to be one of the major pathophysiological changes in PCOS that leads to anovulatory infertility. We hypothesise that electroacupuncture pretreatment improves insulin sensitivity and leads to a higher ovulation rate and greater chances of live birth after the induction of ovulation. The effect of electroacupuncture pretreatment followed by ovulation induction in women with anovulatory PCOS has not been investigated before, and we present here a randomised controlled trial to test this hypothesis by comparing electroacupuncture pretreatment followed by letrozole versus letrozole alone in anovulatory women with PCOS. Methods/analysis This is a multicentre, randomised,and controlled trial. A total of 384 patients will be enrolled in this study and will be randomly allocated by a central randomisation system to the treatment group or the control group in a 1:1 ratio. The treatment group will undergo 16 weeks of electroacupuncture pretreatment followed by 4 cycles of letrozole, and the control group will only undergo 4 cycles of letrozole. The primary outcome will be the live birth rate. All statistical analyses will be performed using the SPSS program V.21.0 (SPSS, Chicago, Illinois, USA), and a p value <0.05 will be considered statistically significant. Ethics/dissemination This study has been approved by the ethics committees of each participating centre. Written consent will be obtained from each patient and her husband before any study procedure is performed. Adverse events will be categorised, and the percentage of patients experiencing adverse events or serious adverse events during the treatment period will be documented. The results of this trial will be disseminated in peer-reviewed journals and presented at international meetings. Trial registration number NCT02491333. PMID:27855085

Appetitive and Consummatory Sexual Behaviors of Rams Treated with Exogenous Testosterone and Exposed to Anestrus Dorper Ewes: Efficacy of the Male Effect.

PubMed

Tejada, Luz M; Meza-Herrera, Cesar A; Rivas-Muñoz, Raymundo; Rodríguez-Martínez, Rafael; Carrillo, Evaristo; Mellado, Miguel; Véliz-Deras, Francisco G

2017-04-01

We determine whether Dorper rams treated with testosterone in the sexual resting season trigger both appetitive and consummatory sexual behaviors and sexual and reproductive outcomes in anestrous ewes at 26° North during March-April. Dorper rams (n = 12, 2.5 years) were randomly divided prior to mating in two groups: GT (treated group; n = 6), treated with testosterone propionate (25 mg i.m. every 3 days × 3 weeks) and GC (control group; n = 6), treated with saline. Thereafter, adult anovulatory Dorper ewes (n = 61) were exposed to the GT-rams while the other group (n = 60) was exposed to the GC-rams. Ram's appetitive sexual behavior was similar (50 %) in both groups, yet the GT-rams exerted 100 % of the consummatory sexual behavior. Sexual and reproductive outcomes of the anestrus females exposed to both male groups considered two phases: 0-15 and 16-25 days from exposure to males. Involved variables were: ewes in estrus, ewes ovulating, duration of estrus, pregnant ewes, and lambed ewes. All the average variables favored those ewes exposed to GT-males: ewes in estrus: 85 versus 40 %; ewes ovulating: 80 versus 53 %; duration of estrus: 37 versus 25 h; pregnant ewes: 60 versus 31 %, and lambed ewes: 57 versus 31 %. Results confirm that adult Dorper rams treated with exogenous testosterone had improved consummatory sexual behavior and induced increased ovulation and pregnancy rates when exposed to anestrus ewes. This feasible and inexpensive testosterone-based protocol through the male effect also enhanced both sexual and reproductive outcomes in previously anestrous Dorper ewes during the natural out-of-season. Results are important to speed up reproductive performance of sheep during the natural anestrous season at this latitude, while also they embrace interesting outcomes from a comparative sexual behavior stand point.

[Influence of undernutrition in the lactating cow on ovulation induction by serum gonadotropins (PMSG) during the post-partum period].

PubMed

Gauthier, D; Yaouanc, A; Cochaud, J; Mauléon, P

1981-01-01

Two experiments were carried out to assess the influence of undernutrition on postpartum ovulation in nursing Charolais cows after PMSG injection. In each experiment, the nursing cows were divided into 2 groups: one fed at a low nutritional level and the other at a normal nutritional level. In the first experiment, 19 animals were injected on post-partum days 15 and 30 with 600 IU of PMSG; in the second experiment, 34 received the same injection on post-partum day 54 after 9 days of priming with a Norgestomet implant. On post-partum day 15, only one cow in each group ovulated. At post-partum day 30, 1 out of 8 cows at the low nutritional plane ovulated vs 5 out of 9 at the normal nutritional plane (P less than 0.05). Likewise, on post-partum day 54, 5 out of 14 cows at the low nutritional plane ovulated vs 17 out of 17 at the normal nutritional level (P less than 0.05). Therefore, there is a time during the post-partum period when the nursing cow ovary does not respond to PMSG by ovulation. The length of this time is increased by undernutrition.

Flotation preferentially selects saccate pollen during conifer pollination.

PubMed

Leslie, Andrew B

2010-10-01

• Among many species of living conifers the presence of pollen with air bladders (saccate pollen) is strongly associated with downward-facing ovules and the production of pollination drops. This combination of features enables saccate pollen grains captured in the pollination drop to float upwards into the ovule. Despite the importance of this mechanism in understanding reproduction in living conifers and in extinct seed plants with similar morphologies, experiments designed to test its effectiveness have yielded equivocal results. • In vitro and in vivo pollination experiments using saccate and nonsaccate pollen were performed using modeled ovules and two Pinus species during their natural pollination period. • Buoyant saccate pollen readily floated through aqueous droplets, separating these grains from nonbuoyant pollen and spores. Ovules that received saccate pollen, nonsaccate pollen or a mixture of both all showed larger amounts and higher proportions of saccate pollen inside ovules after drop secretion. • These results demonstrate that flotation is an effective mechanism of pollen capture and transport in gymnosperms, and suggest that the prevalence of saccate grains and downward-facing ovules in the evolutionary history of seed plants is a result of the widespread use of this mechanism.

Are relationships between pollen-ovule ratio and pollen and seed size explained by sex allocation?

PubMed

Burd, Martin

2011-10-01

Positive correlations between pollen-ovule ratio and seed size, and negative correlations between pollen-ovule ratio and pollen grain size have been noted frequently in a wide variety of angiosperm taxa. These relationships are commonly explained as a consequence of sex allocation on the basis of a simple model proposed by Charnov. Indeed, the theoretical expectation from the model has been the basis for interest in the empirical pattern. However, the predicted relationship is a necessary consequence of the mathematics of the model, which therefore has little explanatory power, even though its predictions are consistent with empirical results. The evolution of pollen-ovule ratios is likely to depend on selective factors affecting mating system, pollen presentation and dispensing, patterns of pollen receipt, pollen tube competition, female mate choice through embryo abortion, as well as genetic covariances among pollen, ovule, and seed size and other reproductive traits. To the extent the empirical correlations involving pollen-ovule ratios are interesting, they will need explanation in terms of a suite of selective factors. They are not explained simply by sex allocation trade-offs. © 2011 The Author(s). Evolution© 2011 The Society for the Study of Evolution.

Comparison of single serum progesterone and endometrial biopsy for confirmation of ovulation in infertile Nigerian women.

PubMed

Ilesanmi, A O; Adeleye, J A; Osotimehin, B O

1995-03-01

Infertility remains a medico-social problem in Nigeria and it accounts for a large percentage of outpatient gynecological consultations. The evaluation of the infertile couple remains a continuing challenge to the practising doctor in this part of the world. The need to evaluate the two methods commonly used for determining ovulation in these patients is indicated. Endometrial biopsy specimen and a single sample for serum progesterone estimation were obtained simultaneously in the luteal phase from 50 normally menstruating infertile Nigerian women. Subsequent analysis showed that a serum progesterone value of 6.6 nmol/l (2.2 ng/ml) or above was always associated with a secretory endometrium. Forty-six cycles yielded sufficient information to compare the two methods for confirmation of ovulation. Patients who ovulated with a progesterone value of 6.6 nmol/l (2.2 ng/ml) were 91.3% (42/46) or above, while 89% (41/46) showed secretory endometrium. Forty-six of the cases 86.9% (40/46) were judged to have ovulated by both parameters while 6.5% demonstrated anovulatory cycle using both criteria. From the study, a significant correlation was obtained between endometrial biopsy and progesterone assay methods in confirming ovulation.

A network control concept for the 30/20 GHz communication system baseband processor

NASA Technical Reports Server (NTRS)

Sabourin, D. J.; Hay, R. E.

1982-01-01

The architecture and system design for a satellite-switched TDMA communication system employing on-board processing was developed by Motorola for NASA's Lewis Research Center. The system design is based on distributed processing techniques that provide extreme flexibility in the selection of a network control protocol without impacting the satellite or ground terminal hardware. A network control concept that includes system synchronization and allows burst synchronization to occur within the system operational requirement is described. This concept integrates the tracking and control links with the communication links via the baseband processor, resulting in an autonomous system operational approach.

An Enhanced Biometric Based Authentication with Key-Agreement Protocol for Multi-Server Architecture Based on Elliptic Curve Cryptography.

PubMed

Reddy, Alavalapati Goutham; Das, Ashok Kumar; Odelu, Vanga; Yoo, Kee-Young

2016-01-01

Biometric based authentication protocols for multi-server architectures have gained momentum in recent times due to advancements in wireless technologies and associated constraints. Lu et al. recently proposed a robust biometric based authentication with key agreement protocol for a multi-server environment using smart cards. They claimed that their protocol is efficient and resistant to prominent security attacks. The careful investigation of this paper proves that Lu et al.'s protocol does not provide user anonymity, perfect forward secrecy and is susceptible to server and user impersonation attacks, man-in-middle attacks and clock synchronization problems. In addition, this paper proposes an enhanced biometric based authentication with key-agreement protocol for multi-server architecture based on elliptic curve cryptography using smartcards. We proved that the proposed protocol achieves mutual authentication using Burrows-Abadi-Needham (BAN) logic. The formal security of the proposed protocol is verified using the AVISPA (Automated Validation of Internet Security Protocols and Applications) tool to show that our protocol can withstand active and passive attacks. The formal and informal security analyses and performance analysis demonstrates that the proposed protocol is robust and efficient compared to Lu et al.'s protocol and existing similar protocols.

The female menstrual cycle does not influence testosterone concentrations in male partners.

PubMed

Strom, Jakob O; Ingberg, Edvin; Druvefors, Emma; Theodorsson, Annette; Theodorsson, Elvar

2012-01-03

The time of ovulation has since long been believed to be concealed to male heterosexual partners. Recent studies have, however, called for revision of this notion. For example, male testosterone concentrations have been shown to increase in response to olfactory ovulation cues, which could be biologically relevant by increasing sexual drive and aggressiveness. However, this phenomenon has not previously been investigated in real-life human settings. We therefore thought it of interest to test the hypothesis that males' salivary testosterone concentrations are influenced by phases of their female partners' menstrual cycle; expecting a testosterone peak at ovulation. Thirty young, healthy, heterosexual couples were recruited. During the course of 30-40 days, the women registered menses and ovulation, while the men registered sexual activity, physical exercise, alcohol intake and illness (confounders), and obtained daily saliva samples for testosterone measurements. All data, including the registered confounders, were subjected to multiple regression analysis. In contrast to the hypothesis, the ovulation did not affect the testosterone levels, and the resulting testosterone profile during the menstrual cycle was on the average flat. The specific main hypothesis, that male testosterone levels on the day of ovulation would be higher than day 4 of the cycle, was clearly contradicted by a type II error(β)-analysis (< 14.3% difference in normalized testosterone concentration; β = 0.05). Even though an ovulation-related salivary testosterone peak was observed in individual cases, no significant effect was found on a group level.

The female menstrual cycle does not influence testosterone concentrations in male partners

PubMed Central

2012-01-01

Background The time of ovulation has since long been believed to be concealed to male heterosexual partners. Recent studies have, however, called for revision of this notion. For example, male testosterone concentrations have been shown to increase in response to olfactory ovulation cues, which could be biologically relevant by increasing sexual drive and aggressiveness. However, this phenomenon has not previously been investigated in real-life human settings. We therefore thought it of interest to test the hypothesis that males' salivary testosterone concentrations are influenced by phases of their female partners' menstrual cycle; expecting a testosterone peak at ovulation. Methods Thirty young, healthy, heterosexual couples were recruited. During the course of 30-40 days, the women registered menses and ovulation, while the men registered sexual activity, physical exercise, alcohol intake and illness (confounders), and obtained daily saliva samples for testosterone measurements. All data, including the registered confounders, were subjected to multiple regression analysis. Results In contrast to the hypothesis, the ovulation did not affect the testosterone levels, and the resulting testosterone profile during the menstrual cycle was on the average flat. The specific main hypothesis, that male testosterone levels on the day of ovulation would be higher than day 4 of the cycle, was clearly contradicted by a type II error(β)-analysis (< 14.3% difference in normalized testosterone concentration; β = 0.05). Conclusions Even though an ovulation-related salivary testosterone peak was observed in individual cases, no significant effect was found on a group level. PMID:22214343

Networking Foundations for Collaborative Computing at Internet Scope

DTIC Science & Technology

2006-01-01

network-supported synchronous multime- dia groupwork at Internet scope and for large user groups. Contributions entail an novel classification for...multimedia resources in interactive groupwork , generalized to the domain of CSCW from the “right to speak” [26]. A floor control protocol mediates access to

A mechanized process algebra for verification of device synchronization protocols

NASA Technical Reports Server (NTRS)

Schubert, E. Thomas

1992-01-01

We describe the formalization of a process algebra based on CCS within the Higher Order Logic (HOL) theorem-proving system. The representation of four types of device interactions and a correctness proof of the communication between a microprocessor and MMU is presented.

Effect of the Transient Pharmacological Inhibition of Mapk3/1 Pathway on Ovulation in Mice

PubMed Central

Siddappa, Dayananda; Beaulieu, Élaine; Gévry, Nicolas; Roux, Philippe P.; Bordignon, Vilceu; Duggavathi, Raj

2015-01-01

Mitogen-activated protein kinase 3/1 (Mapk3/1) pathway is critical for LH signal transduction during ovulation. However, the mechanisms remain incompletely understood. We hypothesized that Mapk pathway regulates ovulation through transcriptional regulation of ovulatory genes. To test this hypothesis we used immature mice superovulated with equine and human chorionic gonadotropins (eCG and hCG) and PD0325901, to inhibit hCG-induced Mapk3/1 activity. Mice received either the inhibitor PD0325901 (25 μg/g, i.p.) or vehicle at 2h before hCG stimulation. Administration of the inhibitor abolished Mapk3/1 phosphorylation in granulosa cells. While vehicle-treated mice ovulated normally, there were no ovulations in inhibitor-treated mice. First, we analyzed gene expression in granulosa cells at 0h, 1h and 4h post-hCG. There was expected hCG-driven increase in mRNA abundance of many ovulation-related genes including Ptgs2 in vehicle-treated granulosa cells, but not (P<0.05) in inhibitor-treated group. There was also reduced mRNA and protein abundance of the transcription factor, early growth response 1 (Egr1) in inhibitor-treated granulosa cells. We then used GRMO2 cell-line to test if Egr1 is recruited to promoter of Ptgs2 followed by chromatin immunoprecipitation with either Egr1 or control antibody. Enrichment of the promoter regions in immunoprecipitants of Egr1 antibody indicated that Egr1 binds to the Ptgs2 promoter. We then knocked down Egr1 expression in mouse primary granulosa cells using siRNA technology. Treatment with Egr1-siRNA inhibited Egr1 transcript accumulation, which was associated with reduced expression of Ptgs2 when compared to control-siRNA treated granulosa cells. These data demonstrate that transient inhibition of LH-stimulated MAPK3/1 activity abrogates ovulation in mice. We conclude that Mapk3/1 regulates ovulation, at least in part, through Egr1 and its target gene, Ptgs2 in granulosa cells of ovulating follicles in mice. PMID:25803847

Local versus systemic effect of ovulation-inducing factor in the seminal plasma of alpacas

PubMed Central

Ratto, Marcelo H; Huanca, Wilfredo; Singh, Jaswant; Adams, Gregg P

2005-01-01

Background Camelids are induced (reflex) ovulators. We have recently documented the presence of an ovulation-inducing factor (OIF) in the seminal plasma of alpacas and llamas. The objective was to test the hypothesis that OIF exerts its effect via a systemic rather than a local route and that endometrial curettage will enhance the ovulatory response to intrauterine deposition of seminal plasma in alpacas. Methods Female alpacas were assigned randomly to 6 groups (n = 15 to 17 per group) in a 2 × 3 factorial design to test the effect of seminal plasma versus phosphate-buffered saline (PBS) given by intramuscular injection, by intrauterine infusion, or by intrauterine infusion after endometrial curettage. Specifically, alpacas in the respective groups were given 1) 2 ml of alpaca seminal plasma intramuscularly, 2) 2 ml of PBS intramuscularly (negative control group), 3) 2 ml of alpaca seminal plasma by intrauterine infusion, 4) 2 ml of PBS by intrauterine infusion (negative control group), 5) 2 ml of alpaca seminal plasma by intrauterine infusion after endometrial curettage, or 6) 2 ml of PBS by intrauterine infusion after endometrial curettage (negative control group). The alpacas were examined by transrectal ultrasonography to detect ovulation and measure follicular and luteal diameters. Results Intramuscular administration of seminal plasma resulted in a higher ovulation rate than intrauterine administration of seminal plasma (93% versus 41%; P < 0.01), while intrauterine seminal plasma after endometrial curettage was intermediate (67%). None of the saline-treated controls ovulated. The diameter of the CL after treatment-induced ovulation was not affected by the route of administration of seminal plasma. Conclusion We conclude that 1) OIF in seminal plasma effects ovulation via a systemic rather than a local route, 2) disruption of the endometrial mucosa by curettage facilitated the absorption of OIF and increased the ovulatory effect of seminal plasma, and 3) ovulation in alpacas is not associated with a physical stimulation of the genital tract, and 4) the alpaca represents an excellent biological model to evaluate the bioactivity of OIF. PMID:16018817

Neural Synchronization and Cryptography

NASA Astrophysics Data System (ADS)

Ruttor, Andreas

2007-11-01

Neural networks can synchronize by learning from each other. In the case of discrete weights full synchronization is achieved in a finite number of steps. Additional networks can be trained by using the inputs and outputs generated during this process as examples. Several learning rules for both tasks are presented and analyzed. In the case of Tree Parity Machines synchronization is much faster than learning. Scaling laws for the number of steps needed for full synchronization and successful learning are derived using analytical models. They indicate that the difference between both processes can be controlled by changing the synaptic depth. In the case of bidirectional interaction the synchronization time increases proportional to the square of this parameter, but it grows exponentially, if information is transmitted in one direction only. Because of this effect neural synchronization can be used to construct a cryptographic key-exchange protocol. Here the partners benefit from mutual interaction, so that a passive attacker is usually unable to learn the generated key in time. The success probabilities of different attack methods are determined by numerical simulations and scaling laws are derived from the data. They show that the partners can reach any desired level of security by just increasing the synaptic depth. Then the complexity of a successful attack grows exponentially, but there is only a polynomial increase of the effort needed to generate a key. Further improvements of security are possible by replacing the random inputs with queries generated by the partners.

Correlations between ovarian follicular blood flow and superovulatory responses in ewes.

PubMed

Oliveira, Maria E F; Feliciano, Marcus A R; D'Amato, Carla C; Oliveira, Luís G; Bicudo, Sony D; Fonseca, Jeferson F; Vicente, Wilter R R; Visco, Elise; Bartlewski, Pawel M

2014-01-10

The primary goal of this study was to employ ultrasonography to examine the ovaries of ewes undergoing superovulatory treatment for correlations between antral follicular blood flow and ovarian responses/embryo yields. Five Santa Inês ewes were subjected to a short- (Days 0-6, Group 1) and five to a long-term progesterone-based protocol (Days 0-12, Group 2) to synchronize estrus and ovulations after the superovulatory treatment. Porcine FSH (pFSH, 200mg) was administered in 8 decreasing doses over 4 days, starting on Days 4 and 10 in Groups 1 and 2, respectively. After CIDR removal, all ewes were bred by a ram and embryos were recovered surgically 7 days later. Transrectal ovarian ultrasonography was performed the day before and on all 4 days of the superovulatory treatment. Both an arbitrary-scale [(0) non-detectable; (1) small; (2) moderate; (3) intense blood flow] and quantitative analysis of the blood flow area were used to assess the follicular blood flow in color Doppler images. There were no significant correlations between the arbitrary blood flow scores and superovulatory responses in the ewes of the present study. However, there was a positive correlation between the quantitative estimates of follicular blood flow on the final day of the superovulatory treatment, and the number (DA: r=0.68, P<0.05; DA/TA×100%: r=0.85, P<0.05) and percentage (DA: r=0.65, P<0.05; DA/TA×100%: r=0.91, P<0.001) of unfertilized eggs (DA: Doppler area, TA: total area of the largest ovarian cross section). This experiment presents a commercially practical tool for predicting superovulatory outcomes in ewes and evidence for the existence of follicular blood flow threshold that may impinge negatively on oocyte quality when surpassed during hormonal ovarian superstimulation. Copyright © 2013 Elsevier B.V. All rights reserved.

Successful pregnancy following low-dose hCG administration in addition to hMG in a patient with hypothalamic amenorrhea due to weight loss.

PubMed

Tsutsumi, Ryo; Fujimoto, Akihisa; Osuga, Yutaka; Harada, Miyuki; Takemura, Yuri; Koizumi, Minako; Yano, Tetsu; Taketani, Yuji

2012-06-01

We describe successful ovulation induction with low-dose hCG administration in addition to hMG in a patient with refractory hypothalamic amenorrhea. A 24-year-old woman with weight loss-related amenorrhea underwent ovulation induction and intracytoplasmic sperm injection (ICSI). Administration of exogenous gonadotropins was ineffective in ovulation induction. Supplementation with low-dose hCG in order to increase luteinizing hormone (LH) activity in the late follicular phase produced late folliculogenesis and steroidogenesis, and ovulation was then successfully induced. This report reacknowledges the critical role that LH plays cooperatively with follicle-stimulating hormone in both folliculogenesis and steroidogenesis.

Modulators of Bufo arenarum ovulation.

PubMed

Ramos, Inés; Cisint, Susana B; Crespo, Claudia A; Medina, Marcela F; Fernández, Silvia N

2008-02-01

In this study we investigated ovulation in vitro using ovary samples from Bufo arenarum with respect to their response to stimulation with homologous pituitary homogenate (HPH) or with progesterone and prostaglandins (PGF2alpha and PGE1) as intermediates of pituitary action. Ovary samples were obtained from animals captured during the breeding period. Our results demonstrate that the ovulatory response to all different inducers was dose dependent, the highest percentage of ovulated oocytes being obtained with HPH treatment. An important increase in the ovulatory response was obtained by the association of PGF2alpha with either HPH or progesterone at suboptimal doses, indicating that this prostaglandin induced a synergistic potentiating effect. Incubation with cyclooxygenase inhibitors (indomethacin or diclofenac sodium) produced a significant decrease in the ovulation induced by HPH, demonstrating that prostaglandins are involved in the action of the pituitary gland in this process. According to our results, PGE1 not only had no participation in the ovulatory process, but also produced an inhibitory effect on ovulation induced by HPH treatment.

Anti-bacterial factors secreted from cumulus cells of ovulated COCs enhance sperm capacitation during in vitro fertilization.

PubMed

Shimada, Masayuki; Mihara, Toshihiro; Kawashima, Ikko; Okazaki, Tetsuji

2013-02-01

The aim of this study was to find immune-related genes expressed in cumulus cells of ovulated cumulus oocyte complexes (COCs) and to clear the functional roles during fertilization process. Ovulated COCs were collected from oviduct 16 hr after the hCG injections followed by eCG priming. The cumulus cells were used for RT-PCR or western blotting study. COCs were also used for in vitro fertilization study. Cramp, Trf, Lyz2, S100a8, and S100a9 were expressed in cumulus cells during ovulation process. The protein levels of CRAMP or transferrin were detected in ovulated COCs and then secreted into hyaluronan-rich matrix. The high dose of these factors reduced the proliferative activity of E. coli; however, the lower levels of them significantly increased the rate of fertilization in in vitro via the induction of sperm capacitation. Cumulus-secreted anti-bacterial factors act on sperm to induce sperm capacitation. © 2012 John Wiley & Sons A/S.

Artificial reproduction of wild and cultured barbel (Barbus barbus, Cyprinidae) under controlled conditions.

PubMed

Targońska, Katarzyna; Kucharczyk, Dariusz; Zarski, Daniel; Cejko, Beata Irena; Krejszeff, Sławomir; Kupren, Krzysztof; Król, Radosław; Dryl, Katarzyna; Kowalski, Radosław Kajetan; Glogowski, Jan

2011-09-01

The aim of this work was to compare the effects of controlled reproduction of cultured and wild common barbel, Barbus barbus (L.). Preparations containing different GnRH analogues and dopamine receptor antagonists (Ovopel, Ovaprim) as well as human chorionic gonadotropin (hCG) (in the case of cultured fish) were applied and their influence on ovulation, spermiation and quality of gametes obtained was determined. No differences in the qualitative or quantitative parameters of semen were found between fish stimulated with different hormonal preparations and those not receiving hormonal stimulation. The high suitability of Ovaprim for ovulation induction in (cultured and wild) barbel was confirmed. The highest synchronisation of ovulation was obtained after the application of Ovopel (18 ± 3 h), but the best results of controlled reproduction (expressed as the percentage of ovulations and survival of embryos) were obtained by applying Ovaprim (83.2 ± 4.1). A significantly higher percentage of ovulation was obtained in cultured fish (80-90%) than in wild fish (< 25%).

New observations on gametogenic development and reproductive experimental tools to support seed yield improvement in cowpea [Vigna unguiculata (L.) Walp].

PubMed

Salinas-Gamboa, Rigel; Johnson, Susan D; Sánchez-León, Nidia; Koltunow, Anna M G; Vielle-Calzada, Jean-Philippe

2016-06-01

Cowpea reproductive tools. Vigna unguiculata L. Walp. (cowpea) is recognized as a major legume food crop in Africa, but seed yields remain low in most varieties adapted to local conditions. The development of hybrid cowpea seed that could be saved after each generation, enabling significant yield increases, will require manipulation of reproductive development from a sexual to an asexual mode. To develop new technologies that could support the biotechnological manipulation of reproductive development in cowpea, we examined gametogenesis and seed formation in two transformable, African-adapted, day-length-insensitive varieties. Here, we show that these two varieties exhibit distinct morphological and phenological traits but share a common developmental sequence in terms of ovule formation and gametogenesis. We present a reproductive calendar that allows prediction of male and female gametogenesis on the basis of sporophytic parameters related to floral bud size and reproductive organ development, determining that gametogenesis occurs more rapidly in the anther than in the ovule. We also show that the mode of megagametogenesis is of the Polygonum-type and not Oenothera-type, as previously reported. Finally, we developed a whole-mount immunolocalization protocol and applied it to detect meiotic proteins in the cowpea megaspore mother cell, opening opportunities for comparing the dynamics of protein localization during male and female meiosis, as well as other reproductive events in this emerging legume model system.

Role of exercise training in polycystic ovary syndrome: a systematic review and meta-analysis.

PubMed

Benham, J L; Yamamoto, J M; Friedenreich, C M; Rabi, D M; Sigal, R J

2018-06-12

Preliminary evidence suggests exercise in polycystic ovary syndrome (PCOS) may improve reproductive and cardiometabolic parameters. Our primary aim was to determine the impact of exercise training on reproductive health in women with PCOS. Our secondary aim was to determine the effect of exercise training on cardiometabolic indices. A systematic review of published literature was conducted using MEDLINE and EMBASE based on a pre-published protocol (PROSPERO CRD42017065324). The search was not limited by year. Randomized controlled trials, non-randomized controlled trials and uncontrolled trials that evaluated an exercise intervention in women with PCOS and reported reproductive outcomes were included. Reproductive outcomes were analysed semi-quantitatively and a meta-analysis was conducted for reported cardiometabolic outcomes. Of 517 screened abstracts, 14 studies involving 617 women with PCOS were included: seven randomized controlled trials, one non-randomized controlled trial and six uncontrolled trials. There were insufficient published data to describe the effect of exercise interventions on ovulation quantitatively, but semi-quantitative analysis suggested that exercise interventions may improve menstrual regularity, pregnancy and ovulation rates. Our meta-analysis found that exercise improved lipid profiles and decreased waist circumference, systolic blood pressure and fasting insulin. The impact of exercise interventions on reproductive function remains unclear. However, our meta-analysis suggests that exercise interventions may improve cardiometabolic profiles in women with PCOS. © 2018 World Obesity Federation.

The Impact of Serum Progesterone Levels on the Results of In Vitro Fertilization Treatments: A Literature Review.

PubMed

Castillo, Jaime Larach Del; Bousamra, Maroun; Fuente, Laura De La; Ruiz-Balda, Jose A; Palomo, Marissa

2015-08-01

The aim of this review is to analyze the relationship between preovulatory progesterone (P) rise and in vitro fertilization (IVF) pregnancy outcomes. It also investigates the sources and effects of rises in progesterone levels, including the underlying mechanisms and potential strategies in preventing its elevation during ovarian stimulation. Progesterone is produced in the early follicular phase in the adrenal gland, which shifts toward the ovaries prior to ovulation. Several factors contribute to the etiology of P level increase including the number of multiple follicles, the overdose of gonadotropins and poor ovarian response. Nowadays, the influence of the preovulatory P rise on IVF outcome remains controversial. Several authors have failed to demonstrate any negative impact, while others reported a detrimental effect associated with the rise of P. It seems that P rise (1.5 ng/ml or 4.77 nmol/l) may have deleterious effects on endometrial receptivity, namely, accelerating the endometrial maturation process that subsequently narrows the period for implantation and thus decreases pregnancy rates. Recent studies have proposed different cutoffs according to the ovarian response, which may be a little high in patients with high response in relation to those of normal response or low response. To prevent a P rise, it might be preferable to use milder stimulation protocols, earlier trigger of ovulation, cryopreservation of all embryos and transfer in the natural cycle.

Contribution to More Patient-Friendly ART Treatment: Efficacy of Continuous Low-Dose GnRH Agonist as the Only Luteal Support—Results of a Prospective, Randomized, Comparative Study

PubMed Central

Pirard, Céline; Loumaye, Ernest; Wyns, Christine

2015-01-01

Background. The aim of this pilot study was to evaluate intranasal buserelin for luteal phase support and compare its efficacy with standard vaginal progesterone in IVF/ICSI antagonist cycles. Methods. This is a prospective, randomized, open, parallel group study. Forty patients underwent ovarian hyperstimulation with human menopausal gonadotropin under pituitary inhibition with gonadotropin-releasing hormone antagonist, while ovulation trigger and luteal support were achieved using intranasal GnRH agonist (group A). Twenty patients had their cycle downregulated with buserelin and stimulated with hMG, while ovulation trigger was achieved using 10,000 IU human chorionic gonadotropin with luteal support by intravaginal progesterone (group B). Results. No difference was observed in estradiol levels. Progesterone levels on day 5 were significantly lower in group A. However, significantly higher levels of luteinizing hormone were observed in group A during the entire luteal phase. Pregnancy rates (31.4% versus 22.2%), implantation rates (22% versus 15.4%), and clinical pregnancy rates (25.7% versus 16.7%) were not statistically different between groups, although a trend towards higher rates was observed in group A. No luteal phase lasting less than 10 days was recorded in either group. Conclusion. Intranasal administration of buserelin is effective for providing luteal phase support in IVF/ICSI antagonist protocols. PMID:25945092

Fertility after deep intra-uterine artificial insemination of concentrated low-volume boar semen doses.

PubMed

Wongtawan, Tuempong; Saravia, Fernando; Wallgren, Margareta; Caballero, Ignacio; Rodríguez-Martínez, Heriberto

2006-03-01

Boar semen can be successfully frozen - highly packed - in small containers (medium-straw, MS or MiniFlatPack, MFP). The use of deep intra-uterine artificial insemination (DIU-AI) can make possible the deposition of small volumes of this thawed, non re-extended semen deeply intra-uterine, close to the sperm reservoir. The present experiments studied the fertility achieved after single or double DIU-AI per oestrus, with special attention to the interval between AI and spontaneous ovulation. Semen from two boars of proven fertility was frozen in MS or MFP holding 1 x 10(9) total spermatozoa. Multiparous (2-5 parity, n=42) crossbred sows were checked for oestrous behaviour after weaning and the occurrence of spontaneous ovulation was checked with transrectal ultrasonography (TUS) to establish the mean interval between onset of oestrus (OO) and ovulation which was found to be when approximately 2/3 of the oestrus period has passed. The sows were, in the following standing oestrus, subjected to DIU-AI using thawed semen from either MS (n=20) or MFP (n=22), inseminated without further re-extension. The sows were randomly allotted to one of three groups: (1) single DIU-AI 8 h before expected ovulation (control group, n=19); (2) single DIU-AI 4 h before expected ovulation (treatment group S, n=15); and (3) double DIU-AI 12 and 4 h before expected ovulation (treatment group D, n=8). Occurrence of spontaneous ovulation was confirmed by TUS, performed as during the first oestrous period and used to determine the real interval of DIU-AI and ovulation. Pregnancy was also confirmed by TUS 28 days after OO in those sows not returning to oestrus. These sows were slaughtered (30-45 days of pregnancy), and the appearance of the reproductive tract and ovaries, the number of live and dead foetuses, of implantation sites and of corpora lutea (CL) were recorded. Sows (n=9) returning to oestrus ("open") were re-inseminated (either once [n=4] or twice [n=5]) the following oestrus with either MFP (n=5) or MS (n=4) and slaughtered 12-14 h post-ovulation for recovery of tubal oocytes and of spermatozoa from the uterotubal junctions (sperm reservoir), to assess the degree of effectiveness of sperm transport. Post-thaw sperm motility was 44.3+/-3.21% in MFP and 42.8+/-0.72% for MS (LSmean+/-S.E.M., n.s.), and did not significantly change from thawing to AI. The DIU-AI could be performed in all sows, but insertion was difficult (slow >5 min) in 5/42 sows. Four of these sows returned to oestrus. Pregnancy rate averaged 35% (group D: 25%, group S: 40%, control: 36%, n.s.). The interval between DIU-AIs and spontaneous ovulation varied largely, ranging from -13 to -3 h for group C, for group S from -11 to +3 h and for group D from -17 to -4 h. Pregnancy rates were clearly related to the interval DIU-AI and ovulation, being highest (60%, 12/20) when AI occurred between 8 and 4 h before spontaneous (not expected) ovulation. The number of implantation sites ranged 6-22 (n.s. among groups), and the number of alive foetuses 2-11 (n.s. among groups). Implantation rate (total number of implantations/CL) ranged 48.0-69.7% being highest in the D-group (P<0.05). The examination of the "open" sows slaughtered 12-14 h post-ovulation revealed few recovered oocytes were fertilized (approximately 10%). Only 40% of oocytes had spermatozoa bound to the zona pellucida, not more than two spermatozoa per oocyte. Moreover, low sperm numbers (approximately 4000) were found in the sperm reservoirs (UTJs), irrespective of using single or double DIU-AI (n.s.). The highest values (P<0.05) for these variables were recorded when DIU-AI (either single or double [second AI]) occurred 4-8 h before ovulation, especially when MFP-semen was used (P<0.05). (1) DIU-AI can be easily performed in most sows; (2) pregnancies can be obtained by the DIU-AI of low volumes of highly concentrated frozen-thawed boar semen, once or twice during oestrus, but fertility is still low, probably owing to an unsatisfactory sperm transport when expected and real ovulation differ; and (3) fertility is related to the interval DIU-AI and ovulation which should be -8 to -4 h of spontaneous ovulation and to the package, MFP having shown better results in vivo. The results stress the need for careful, and frequent, control of oestrus signs.

Successful ovulation induction, conception, and normal delivery after chronic therapy with etanercept: a recombinant fusion anti-cytokine treatment for rheumatoid arthritis.

PubMed

Sills, E S; Perloe, M; Tucker, M J; Kaplan, C R; Palermo, G D

2001-11-01

Etanercept (Enbrel; Wyeth-Ayerst/Immunex Inc, Seattle, WA, USA) is a subcutaneously administered novel fusion protein consisting of the extracellular ligand-binding domain of the 75 kD receptor for tumor necrosis factor-alpha (anti-TNFalpha) and the Fc portion of human IgG1. The agent is synthesized by plasmid transfection of a Chinese hamster ovary cell line, utilizing recombinant DNA technology. Etanercept was approved by the US FDA for treatment of multi-drug resistant rheumatoid arthritis in 1998, but no human data exist regarding the impact of anti-TNFalpha therapy on human reproductive function or its use before ovulation induction. As TNFalpha potentiates collagenolysis via matrix metalloproteinase gene expression (thereby facilitating ovulation), there exists a theoretical risk that TNFalpha-inhibition could exert an undesirable effect on ovulation and pregnancy. In this report, we describe the first case of ovulation induction, intrauterine insemination, normal pregnancy and singleton delivery of a healthy infant following chronic ( > 1 year) pre-ovulatory TNFalpha-inhibitor therapy for rheumatoid arthritis. Reproductive endocrinologists and obstetrician-gynecologists should be familiar with etanercept therapy in the context of severe rheumatic disease, and offer appropriate reassurance regarding its safe use for infertility patients planning ovulation induction.

Comparison of clomiphene citrate and letrozole for ovulation induction in women with polycystic ovary syndrome: a prospective randomized trial.

PubMed

Liu, Chang; Feng, Guimei; Huang, Wei; Wang, Qiuyi; Yang, Shiyuan; Tan, Jing; Fu, Jing; Liu, Dong

2017-11-01

To compare the therapeutic efficacy of clomiphene citrate (CC) and letrozole (LE) on ovulation, pregnancy, and live birth in women with polycystic ovary syndrome (PCOS); and to ensure if LE can replace CC as the first-line therapy for ovulation induction in these women. This is a prospectively, randomized, controlled trial in the tertiary hospital. Two-hundred and sixty-eight anovulatory PCOS patients were treated by CC or CC plus metformin and LE or LE plus metformin for three continuous cycles or conception; their ovulation rates, pregnancy rates, and live birth rates were calculated and compared. No significant difference was noted among the four groups regarding to the baseline data of clinical manifestations, serum sex hormone levels, and serum insulin levels. A total of 240 patients completed the therapies. The ovulation rate was significantly higher in the group LE than the group CC; however, no significant difference was noted between the groups LE and CC, CC, and CC + MET, or LE and LE + MET in the pregnancy rate, abortion rate, and live birth rate. No birth defect was found in the total of 63 newborns. CC regimen was still recommended to be the first-line therapy of ovulation induction for PCOS.

Efficacy of Clindamycin Vaginal Ovule (3-Day Treatment) vs. Clindamycin Vaginal Cream (7-Day Treatment) in Bacterial Vaginosis

PubMed Central

Peipert, Jeffrey F.; McGregor, James A.; Livengood, Charles; Martin, Maureen; Robbins, Jill; Wajszczuk, Charles P.

2001-01-01

Objective: To compare the efficacy and safety of a 3-day regimen of clindamycin vaginal ovules with a 7-day regimen of clindamycin vaginal cream for the treatment of bacterial vaginosis (BV) Methods: Women with a clinical diagnosis of BV were treated with a 3-day course of clindamycin ovules or a 7-day course of clindamycin cream administered intravaginally. Three hundred and eighty-four patients received study drug and were included in the evaluable patient population (ovule group, n = 204; cream group, n = 180). Assessments included pelvic examination and diagnostic testing. Primary efficacy endpoints were a resolution of two of three diagnostic criteria at the first follow-up visit and three of three diagnostic criteria at the second. Results: Cure rates in the evaluable patient population were similar between treatment groups: 53.7% (109/204) for the ovule group and 47.8% (85/180) for the cream group (p = 0.2471, 95% CI– 4.1–16.0%). The most commonly reported medical event, vulvovaginal pruritus, had similar incidence in both treatment groups. Conclusions: A 3-day course of clindamycin vaginal ovules is as effective and well-tolerated as a 7-day course of clindamycin vaginal cream in the treatment of BV. PMID:11368263

Myeloperoxidase in blood neutrophils during normal and abnormal menstrual cycles in women of reproductive age.

PubMed

Shibata, T; Sakamoto, J; Osaka, Y; Neyatani, N; Fujita, S; Oka, Y; Takagi, H; Mori, H; Fujita, H; Tanaka, Y; Sasagawa, T

2017-04-01

We previously reported that granulocyte colony-stimulating factor (G-CSF) plays a critical role in ovulation, suggesting that neutrophils may maintain ovulation. We assessed myeloperoxidase (MPO), a major and specific enzyme of neutrophils, in women with abnormal and normal menstrual cycles to clarify the relationship between MPO and ovulation. We analyzed MPO activity in blood neutrophils of women with abnormal menstrual cycles (indicative of anovulation, n = 12) and age- and body mass index-matched normal menstrual cycles (indicative of ovulation, n = 24) using two parameters as a marker of MPO, Neut X and mean peroxidase index (MPXI). MPO of women with abnormal menstrual cycles was significantly lower than that of women with normal menstrual cycles [Neut X: 62.6 ± 1.1 (mean ± standard error of the mean) vs. 66.2 ± 0.3, P = 0.009; MPXI: -0.54 ± 1.66 vs. 4.91 ± 0.53, P = 0.008]. Among women with normal menstrual cycles, MPO was highest in the follicular phase (Neut X: 67.0 ± 0.3; P = 0.033). The difference in MPO between women with abnormal and normal menstrual cycles and the upregulation of MPO before ovulation suggest that neutrophils and MPO are closely related to ovulation. © 2016 John Wiley & Sons Ltd.

Evolutionary and ecological consequences of multiscale variation in pollen receipt for seed production.

PubMed

Schreiber, Sebastian J; Rosenheim, Jay A; Williams, Neal W; Harder, Lawrence D

2015-01-01

Variation in resource availability can select for traits that reduce the negative impacts of this variability on mean fitness. Such selection may be particularly potent for seed production in flowering plants, as they often experience variation in pollen receipt among individuals and among flowers within individuals. Using analytically tractable models, we examine the optimal allocations for producing ovules, attracting pollen, and maturing seeds in deterministic and stochastic pollen environments. In deterministic environments, the optimal strategy attracts sufficient pollen to fertilize every ovule and mature every zygote into a seed. Stochastic environments select for allocations proportional to the risk of seed production being limited by zygotes or seed maturation. When producing an ovule is cheap and maturing a seed is expensive, among-plant variation selects for attracting more pollen at the expense of producing fewer ovules and having fewer resources for seed maturation. Despite this increased allocation, such populations are likely to be pollen limited. In contrast, within-plant variation generally selects for an overproduction of ovules and, to a lesser extent, pollen attraction. Such populations are likely to be resource limited and exhibit low seed-to-ovule ratios. These results highlight the importance of multiscale variation in the evolution and ecology of resource allocations.

Anatomy of ovary and ovule in dandelions (Taraxacum, Asteraceae).

PubMed

Musiał, K; Płachno, B J; Świątek, P; Marciniuk, J

2013-06-01

The genus Taraxacum Wigg. (Asteraceae) forms a polyploid complex within which there are strong links between the ploidy level and the mode of reproduction. Diploids are obligate sexual, whereas polyploids are usually apomictic. The paper reports on a comparative study of the ovary and especially the ovule anatomy in the diploid dandelion T. linearisquameum and the triploid T. gentile. Observations with light and electron microscopy revealed no essential differences in the anatomy of both the ovary and ovule in the examined species. Dandelion ovules are anatropous, unitegmic and tenuinucellate. In both sexual and apomictic species, a zonal differentiation of the integument is characteristic of the ovule. In the integumentary layers situated next to the endothelium, the cell walls are extremely thick and PAS positive. Data obtained from TEM indicate that these special walls have an open spongy structure and their cytoplasm shows evidence of gradual degeneration. Increased deposition of wall material in the integumentary cells surrounding the endothelium takes place especially around the chalazal pole of the embryo sac as well as around the central cell. In contrast, the integumentary cells surrounding the micropylar region have thin walls and exhibit a high metabolic activity. The role of the thick-walled integumentary layers in the dandelion ovule is discussed. We also consider whether this may be a feature of taxonomic importance.

Effects of a single use of the GnRH analog buserelin on the induction of ovulation and endocrine profiles in heavy draft mares.

PubMed

Miki, Wataru; Oniyama, Hiroyuki; Takeda, Naomasa; Kimura, Yuki; Haneda, Shingo; Matsui, Motozumi; Taya, Kazuyoshi; Nambo, Yasuo

2016-01-01

We observed structural changes in the follicles and uterus of heavy draft mares during estrus and examined the effect of a single injection of the gonadotropin-releasing hormone analog buserelin on ovulation and endocrine profiles. Twenty-two heavy draft mares were divided into a buserelin-treated group (n=8) and a control group (n=14). Mares were given an intramuscular injection of 40 µg buserelin when they presented signs of estrus to a teaser stallion, had ≥45 mm diameter follicles, and presented decreased uterine edema compared with the previous examination. The follicles and uterus were monitored using transrectal ultrasound imaging and measurement of blood levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), progesterone, and estradiol-17β. The ovulation rates within 48 hr was significantly higher in the treated group (100%, 8/8) than in the control group (57.1%, 8/14; P=0.051). The mean ± SEM time before confirmation of ovulation was 29 ± 9 hr for the treated group and 59 ± 7 hr for the control group. There were no significant differences in mating frequency, double ovulation rate, or fertility rate between the two groups. One to two days after administering buserelin, LH and FSH temporarily increased, and in the control group, LH was high during ovulation, whereas FSH temporarily increased with the growth of the follicle. These results indicate that a single injection of 40 µg buserelin when follicles are at least 45 mm in diameter and uterine edema is decreased is effective for inducing ovulation.

Parturition to resumption of ovarian cyclicity: comparative aspects of beef and dairy cows.

PubMed

Crowe, M A; Diskin, M G; Williams, E J

2014-05-01

There is a variable anoestrous period following parturition in the cow. Follicular growth generally resumes within 7 to 10 days in the majority of cows associated with a transient FSH rise that occurs within 3 to 5 days of parturition. Dairy cows that are not nutritionally stressed generally ovulate their first postpartum dominant follicle (~15 days), whereas beef suckler cows in good body condition normally have a mean of 3.2±0.2 dominant follicles (~30 days) to first ovulation; moreover, beef cows in poor body condition have a mean of 10.6±1.2 dominant follicles (~70 to 100 days) to first ovulation. The lack of ovulation of dominant follicles during the postpartum period is associated with infrequent LH pulses, with both maternal-offspring bonding and low body condition score (BCS) at calving being implicated as the predominant causes of delayed resumption of cyclicity in nursed beef cows. In dairy cows, the normal pattern of early resumption of ovulation may be delayed in high-yielding Holstein type cows generally owing to the effects of severe negative energy balance, dystocia, retained placental membranes and uterine infections. First ovulation, in both dairy and beef cows, is generally silent (i.e., no behavioural oestrus) and followed by a short inter-ovulatory interval (>70%). The key to optimizing the resumption of ovulation in both beef and dairy cows is appropriate pre-calving nutrition and management so that cows calve down in optimal body condition (BCS; 2.75 to 3.0) with postpartum body condition loss restricted to <0.5 BCS units.

Review: aromatase inhibitors for ovulation induction.

PubMed

Casper, Robert F; Mitwally, Mohamed F M

2006-03-01

For the last 40 yr, the first line of treatment for anovulation in infertile women has been clomiphene citrate (CC). CC is a safe, effective oral agent but is known to have relatively common antiestrogenic endometrial and cervical mucous side effects that could prevent pregnancy in the face of successful ovulation. In addition, there is a significant risk of multiple pregnancy with CC, compared with natural cycles. Because of these problems, we proposed the concept of aromatase inhibition as a new method of ovulation induction that could avoid many of the adverse effects of CC. The objective of this review was to describe the different physiological mechanisms of action for CC and aromatase inhibitors (AIs) and compare studies of efficacy for both agents for ovulation induction. We conducted a systematic review of all the published studies, both controlled and noncontrolled, comparing CC and AI treatment, either alone or in combination with gonadotropins, for ovulation induction or augmentation, identified through the Entrez-PubMed search engine. Because of the recent acceptance of the concept of using AIs for ovulation induction, few controlled studies were identified, and the rest of the studies were pilot or preliminary comparisons. Based on these studies, it appears that AIs are as effective as CC in inducing ovulation, are devoid of any antiestrogenic side effects, result in lower serum estrogen concentrations, and are associated with good pregnancy rates with a lower incidence of multiple pregnancy than CC. When combined with gonadotropins for assisted reproductive technologies, AIs reduce the dose of FSH required for optimal follicle recruitment and improve the response to FSH in poor responders. Preliminary evidence suggests that AIs may replace CC in the future because of similar efficacy with a reduced side effect profile. Although worldwide experience with AIs for ovulation induction is increasing, at present, definitive studies in the form of randomized controlled trials comparing CC with AIs are lacking.

[Optimal Ovulation Induction in Polycystic Ovary Syndrome Resistant to Clomiphene Citrate or Letrozole.

PubMed

Chen, Ying; Zhang, Dan

2016-11-01

To investigate the optimal ovulation induction with the combination of combining letrozole(LE),clomiphene citrate (CC),and human menopausal gonadotropin (HMG) in polycystic ovary syndrome(PCOS) patients resistant to CC or LE. Two hundreds nine PCOS patients (209 cycles) resistant to CC or LE were randomly divided into three groups: CC+HMG group (59 cycles),LE+HMG group (72 cycles) and LE+CC group (78 cycles).The patients in LE+CC group unable to form the dominant follicle after 54 cycles were enrolled into LE+CC+HMG group.Maximum follicle diameter (MFD),endometrial thickness,number of follicles (diameter>1.4 cm),the level of serum estradiol (E2) were measured on the day of HMG administration.Also these results were observed and compared including the duration of treatment,dosage of HMG,number of ovulated follicles,clinical pregnancy rate,biochemical pregnancy rate,early abortion rate,twinning rate,and ectopic pregnancy rate. The ovulation rate was significantly lower in LE+CC group (30.77%) ( P <0.05),but similar in the other three groups.The number of >1.4 cm follicles and ovulated follicles,ovulation duration and E2 concentration in LE+CC group were also at a lower level ( P <0.05).The patients in LE+CC+HMG group showed higher E2 level and more HMG consumption ( P <0.05).There was no statistical difference in endometrial thickness,MFD,clinical pregnancy rate,biochemical pregnancy rate,early abortion rate and twinning rate among these groups ( P >0.05).No severe ovarian hyperstimulation syndrome (OHSS) or luteinized unruptured follicle (LUF) occurred. Combintion of LE with CC could achieve 1/3 ovulation induction in PCOS resistant to CC or LE alone.When both combined with HMG,the induction of ovulation could be significantly higher than LE+HMG and CC+HMG,while the risk of multiple pregnancy and OHSS was reduced.

Chronology of early embryonic development and embryo uterine migration in alpacas.

PubMed

Picha, Y; Tibary, A; Memon, M; Kasimanickam, R; Sumar, J

2013-03-01

The objectives were to: (1) describe the chronology of early embryonic development from ovulation to entry into the uterus; and (2) to determine the timing of embryo migration to the left uterine horn when ovulation occurred from the right ovary. The experiment was conducted in Peru. Females (n = 132) were randomly assigned to 15 experimental groups. All females were mated to an intact male, given 50 μg GnRH im (Cystorelin) and ovulation time determined by transrectal ultrasonography, conducted every 6 hours, starting 24 hours postmating. Animals were slaughtered at a specific intervals postovulation and reproductive tracts were recovered and subjected to oviductal and uterine flushing for females slaughtered between 1 and 6 days postovulation (dpo; Day 0 = ovulation) and uterine flushing for females slaughtered from 7 to 15 dpo for recovery of oocytes/embryos. Season of mating did not influence the interval from mating to ovulation (winter: 29 ± 6 hours vs. summer: 30 ± 6 hours; P = 0.49). Ovulation rates for females mated during winter and summer were 92% versus 100%, respectively (P = 0.05). Fertilization rates for winter and summer mated females were 72% and 82% (P = 0.29). Unfertilized ova were not retained in the uterine tube. All embryos collected were in the uterine tube ipsilateral to the side of ovulation between 1 and 5 dpo. Embryos reached the uterus on 6 dpo. Embryos began to elongate on 9 dpo; at this time, 83% of embryos derived from right-ovary ovulations were collected from the left uterine horn. Embryos occupied the entire uterine cavity by 10 dpo. In conclusion, we characterized early embryo development and location of embryo during its early developmental stages in alpaca. This was apparently the first report regarding chronology of embryo development and migration to the left horn in alpaca which merits further investigation regarding its role in maternal recognition of pregnancy. Copyright © 2013 Elsevier Inc. All rights reserved.

Unilateral intrauterine horn insemination of fresh semen in cats.

PubMed

Tsutsui, T; Tanaka, A; Takagi, Y; Nakagawa, K; Fujimoto, Y; Murai, M; Anzai, M; Hori, T

2000-12-01

The sperm count required were investigated to obtain a conception rate of 80% by unilateral intrauterine insemination (UIUI) of fresh semen in cats. The conception rates obtained by insemination before and after ovulation were also examined. Thirty-six female cats aged 1-7 years were used in the experiments, and the number of experimental cases was 44. Seven male cats aged 2-12 years from which semen could be collected by the artificial vagina method were used. In artificial insemination, 100 iu x 2 or 250 iu of hCG was administered on days 2-4 of estrus, and sperm were introduced into the uterine horn with a greater number of ovulations (or mature follicles) 15, 20 and 30 hr after hCG administration by laparotomy. The inseminated sperm counts were 2 x 10(6) (Exp. 1). 4 x 10(6) (Exp. 2), and 8 x 10(6) (Exp. 3). As a result, ovulation was induced in 42 of 44 cases (induction rate: 95.5%) regardless of the dosage of hCG. Conception was obtained by UIUI in two of 16 animals (conception rate: 12.5%) in the Exp. 1, five of 16 animals (31.3%) in Exp. 2, and eight of 10 animals (80.0%) in Exp. 3. Regarding the relationship between the ovulation state at insemination and conception, the conception rate obtained by insemination before ovulation was clearly higher than that obtained by insemination after ovulation (p<0.05). Regarding the number of kits compared to the number of ovulations on the inseminated side, the percentages of cases in which the number of kits exceeded the number of ovulations on the inseminated side were similar in all groups inseminated with a different number of sperm. It is therefore necessary to investigate conception rates obtained by bilateral insemination to increase the fertility rate. Based on the above findings, it was shown that the sperm count required for fertilization by UIUI is 8 x 10(6).

Effects of acute feed restriction combined with targeted use of increasing luteinizing hormone content of follicle-stimulating hormone preparations on ovarian superstimulation, fertilization, and embryo quality in lactating dairy cows

PubMed Central

Bender, R. W.; Hackbart, K. S.; Dresch, A. R.; Carvalho, P. D.; Vieira, L. M.; Crump, P. M.; Guenther, J. N.; Fricke, P. M.; Shaver, R. D.; Combs, D. K.; Wiltbank, M. C.

2018-01-01

Multiple metabolic and hormonal factors can affect the success of protocols for ovarian superstimulation. In this study, the effect of acute feed restriction and increased LH content in the superstimulatory FSH preparation on numbers of ovulations, fertilization, and embryo quality in lactating dairy cows was evaluated. Two experiments were performed using a Latin square design with treatments arranged as a 2 × 2 factorial: feed restriction (FR; 25% reduction in dry matter intake) compared with ad libitum (AL) feeding, combined with high (H) versus low (L) LH in the last 4 injections of the superstimulatory protocol. As expected, FR decreased circulating insulin concentrations (26.7 vs. 46.0 μU/mL). Two analyses were performed: one that evaluated the complete Latin square in experiment 2 and a second that evaluated only the first periods of experiments 1 and 2. For both analyses, follicle numbers, ovulation rates, and corpora lutea on d 7 were not different. In the first period analysis of experiments 1 and 2, we observed an interaction between feed allowance and amount of LH on fertilization rates, percentage of embryos or oocytes that were quality 1 and 2 embryos, and number of embryos or oocytes that were degenerate. Fertilization rates were greater for the AL-L (89.4%) and FR-H (80.1%) treatments compared with the AL-H (47.9%) and FR-L (59.9%) treatments. Similarly, the proportion of total embryos or oocytes designated as quality 1 and 2 embryos was greater for AL-L (76.7%) and FR-H (73.4%) treatments compared with AL-H (35.6%) and FR-L (47.3%) treatments. In addition, the number of degenerate embryos was decreased for AL-L (1.3) and FR-H (0.4) treatments compared with the AL-H (2.6) and FR-L (2.3) treatments. Thus, cows with either too low (FR-L) or too high (AL-H) insulin and LH stimulation had lesser embryo production after superstimulation because of reduced fertilization rate and increased percentage of degenerate embryos. Therefore, interaction of the gonadotropin content of the superstimulatory preparation with the nutritional program of the donor cow needs to be considered to optimize success of ovarian superstimulatory protocols. PMID:24359829

Effects of excess metabolizable protein on ovarian function and circulating amino acids of beef cows: 1. Excessive supply from corn gluten meal or soybean meal.

PubMed

Geppert, T C; Meyer, A M; Perry, G A; Gunn, P J

2017-04-01

In the dairy industry, excess dietary CP is consistently correlated with decreased conception rates. However, the source from which excess CP is derived and how it affects reproductive function in beef cattle is largely undefined. The objective of this experiment was to determine the effects of feeding excess metabolizable protein (MP) from feedstuffs differing in rumen degradability on ovulatory follicular dynamics, subsequent corpus luteum (CL) development, steroid hormone production and circulating amino acids (AA) in beef cows. Non-pregnant, non-lactating mature beef cows (n=18) were assigned to 1 of 2 isonitrogenous diets (150% of MP requirements) designed to maintain similar BW and body condition score (BCS) between treatments. Diets consisted of ad libitum corn stalks supplemented with corn gluten meal (moderate rumen undegradable protein (RUP); CGM) or soybean meal (low RUP; SBM). After a 20-day supplement adaptation period, cows were synchronized for ovulation. After 10 days of synchronization, gonadotropin releasing hormone (GnRH) was administered to reset ovarian follicular growth. Starting at GnRH administration and daily thereafter until spontaneous ovulation, transrectal ultrasonography was used to diagram ovarian follicular growth, and blood samples were collected for hormone, metabolite and AA analyses. After 7 days of visual detection of estrus, CL size was determined via ultrasound. Data were analyzed using the MIXED procedures of SAS. As designed, cow BW and BCS were not different (P⩾0.33). Ovulatory follicular wavelength, antral follicle count, ovulatory follicle size at dominance and duration of dominance were not different (P>0.13) between treatments. Cows supplemented with CGM had greater post-dominance ovulatory follicle growth, larger dominant follicles at spontaneous luteolysis, shorter proestrus, and larger ovulatory follicles (P⩽0.03) than SBM cows. No differences (P⩾0.44) in peak estradiol, ratio of estradiol to ovulatory follicle volume, or plasma urea nitrogen were observed. While CL volume and the ratio of progesterone to CL volume were not affected by treatment (P⩾0.24), CGM treated cows tended to have decreased (P=0.07) circulating progesterone 7 days post-estrus compared with SBM cows. Although total circulating plasma AA concentration did not differ (P=0.70) between treatments, CGM cows had greater phenylalanine (P=0.03) and tended to have greater leucine concentrations (P=0.07) than SBM cows. In summary, these data illustrate that excess MP when supplemented to cows consuming a low quality forage may differentially impact ovarian function depending on ruminal degradability of the protein source.

Characterizing Deep Brain Stimulation effects in computationally efficient neural network models.

PubMed

Latteri, Alberta; Arena, Paolo; Mazzone, Paolo

2011-04-15

Recent studies on the medical treatment of Parkinson's disease (PD) led to the introduction of the so called Deep Brain Stimulation (DBS) technique. This particular therapy allows to contrast actively the pathological activity of various Deep Brain structures, responsible for the well known PD symptoms. This technique, frequently joined to dopaminergic drugs administration, replaces the surgical interventions implemented to contrast the activity of specific brain nuclei, called Basal Ganglia (BG). This clinical protocol gave the possibility to analyse and inspect signals measured from the electrodes implanted into the deep brain regions. The analysis of these signals led to the possibility to study the PD as a specific case of dynamical synchronization in biological neural networks, with the advantage to apply the theoretical analysis developed in such scientific field to find efficient treatments to face with this important disease. Experimental results in fact show that the PD neurological diseases are characterized by a pathological signal synchronization in BG. Parkinsonian tremor, for example, is ascribed to be caused by neuron populations of the Thalamic and Striatal structures that undergo an abnormal synchronization. On the contrary, in normal conditions, the activity of the same neuron populations do not appear to be correlated and synchronized. To study in details the effect of the stimulation signal on a pathological neural medium, efficient models of these neural structures were built, which are able to show, without any external input, the intrinsic properties of a pathological neural tissue, mimicking the BG synchronized dynamics.We start considering a model already introduced in the literature to investigate the effects of electrical stimulation on pathologically synchronized clusters of neurons. This model used Morris Lecar type neurons. This neuron model, although having a high level of biological plausibility, requires a large computational effort to simulate large scale networks. For this reason we considered a reduced order model, the Izhikevich one, which is computationally much lighter. The comparison between neural lattices built using both neuron models provided comparable results, both without traditional stimulation and in presence of all the stimulation protocols. This was a first result toward the study and simulation of the large scale neural networks involved in pathological dynamics.Using the reduced order model an inspection on the activity of two neural lattices was also carried out at the aim to analyze how the stimulation in one area could affect the dynamics in another area, like the usual medical treatment protocols require.The study of population dynamics that was carried out allowed us to investigate, through simulations, the positive effects of the stimulation signals in terms of desynchronization of the neural dynamics. The results obtained constitute a significant added value to the analysis of synchronization and desynchronization effects due to neural stimulation. This work gives the opportunity to more efficiently study the effect of stimulation in large scale yet computationally efficient neural networks. Results were compared both with the other mathematical models, using Morris Lecar and Izhikevich neurons, and with simulated Local Field Potentials (LFP).

Somatic embryos from culture ovules of polyembryonic Mangifera indica L.

PubMed

Litz, R E; Knight, R L; Gazit, S

1982-12-01

Ovules were aseptically removed from 2 month old fruits of 9 naturally polyembryonic cultivars and 1 monoembryonic cultivar of mango (Mangifera indica L.). Ovules were placed into culture on solid Murashige and Skoog medium that had been modified by the addition of half strength major salts and chelated iron, 6% sucrose, 400 mg/l glutamine, 100 mg/l ascorbic acid with or without the following growth regulators: 20% (v/v) CW, 1 or 2 mg/1 BA. Somatic embryogenesis occurred from the nucellus excised from the ovules of 5 of the naturally polyembryonic cultivars after 1-2 months in culture. Somatic embryogenesis was not apparently affected by the growth regulator composition of the media; however, efficient somatic embryogenesis only occurred in liquid containing 20% CW.

Ovarian function in South American camelids (alpacas, llamas, vicunas, guanacos).

PubMed

Vaughan, Jane

2011-04-01

Ultrasound technology and hormone assays have provided a better understanding of folliculogenesis and ovulation in South American camelids in the last two decades. Females exhibit waves of ovarian follicular growth and are induced ovulators and therefore do not exhibit oestrous cycles in the manner of spontaneously ovulating species such as sheep and cattle. There is much variation in inter-wave interval among camelid species (alpaca/llama 10-22 days, vicuna 4-11 days), within species and within individual animals as the range of each phase of follicular growth is wide. Ovulation occurs 24-30h after mating and luteolysis occurs approximately 10 days later if conception fails to occur. Copyright © 2010 Elsevier B.V. All rights reserved.

Conifer ovulate cones accumulate pollen principally by simple impaction.

PubMed

Cresswell, James E; Henning, Kevin; Pennel, Christophe; Lahoubi, Mohamed; Patrick, Michael A; Young, Phillipe G; Tabor, Gavin R

2007-11-13

In many pine species (Family Pinaceae), ovulate cones structurally resemble a turbine, which has been widely interpreted as an adaptation for improving pollination by producing complex aerodynamic effects. We tested the turbine interpretation by quantifying patterns of pollen accumulation on ovulate cones in a wind tunnel and by using simulation models based on computational fluid dynamics. We used computer-aided design and computed tomography to create computational fluid dynamics model cones. We studied three species: Pinus radiata, Pinus sylvestris, and Cedrus libani. Irrespective of the approach or species studied, we found no evidence that turbine-like aerodynamics made a significant contribution to pollen accumulation, which instead occurred primarily by simple impaction. Consequently, we suggest alternative adaptive interpretations for the structure of ovulate cones.

Conifer ovulate cones accumulate pollen principally by simple impaction

PubMed Central

Cresswell, James E.; Henning, Kevin; Pennel, Christophe; Lahoubi, Mohamed; Patrick, Michael A.; Young, Phillipe G.; Tabor, Gavin R.

2007-01-01

In many pine species (Family Pinaceae), ovulate cones structurally resemble a turbine, which has been widely interpreted as an adaptation for improving pollination by producing complex aerodynamic effects. We tested the turbine interpretation by quantifying patterns of pollen accumulation on ovulate cones in a wind tunnel and by using simulation models based on computational fluid dynamics. We used computer-aided design and computed tomography to create computational fluid dynamics model cones. We studied three species: Pinus radiata, Pinus sylvestris, and Cedrus libani. Irrespective of the approach or species studied, we found no evidence that turbine-like aerodynamics made a significant contribution to pollen accumulation, which instead occurred primarily by simple impaction. Consequently, we suggest alternative adaptive interpretations for the structure of ovulate cones. PMID:17986613

Constellation Program Electrical Ground Support Equipment Research and Development

NASA Technical Reports Server (NTRS)

McCoy, Keegan S.

2010-01-01

At the Kennedy Space Center, I engaged in the research and development of electrical ground support equipment for NASA's Constellation Program. Timing characteristics playa crucial role in ground support communications. Latency and jitter are two problems that must be understood so that communications are timely and consistent within the Kennedy Ground Control System (KGCS). I conducted latency and jitter tests using Alien-Bradley programmable logic controllers (PLCs) so that these two intrinsic network properties can be reduced. Time stamping and clock synchronization also play significant roles in launch processing and operations. Using RSLogix 5000 project files and Wireshark network protocol analyzing software, I verified master/slave PLC Ethernet module clock synchronization, master/slave IEEE 1588 communications, and time stamping capabilities. All of the timing and synchronization test results are useful in assessing the current KGCS operational level and determining improvements for the future.

Synchronization of hybrid coupled reaction-diffusion neural networks with time delays via generalized intermittent control with spacial sampled-data.

PubMed

Lu, Binglong; Jiang, Haijun; Hu, Cheng; Abdurahman, Abdujelil

2018-05-04

The exponential synchronization of hybrid coupled reaction-diffusion neural networks with time delays is discussed in this article. At first, a generalized intermittent control with spacial sampled-data is introduced, which is intermittent in time and data sampling in space. This type of control strategy not only can unify the traditional periodic intermittent control and the aperiodic case, but also can lower the update rate of the controller in both temporal and spatial domains. Next, based on the designed control protocol and the Lyapunov-Krasovskii functional approach, some novel and readily verified criteria are established to guarantee the exponential synchronization of the considered networks. These criteria depend on the diffusion coefficients, coupled strengths, time delays as well as control parameters. Finally, the effectiveness of the proposed control strategy is shown by a numerical example. Copyright © 2018 Elsevier Ltd. All rights reserved.

Assessing the mental frame syncing in the elderly: a virtual reality protocol.

PubMed

Serino, Silvia; Cipresso, Pietro; Gaggioli, Andrea; Riva, Giuseppe

2014-01-01

Decline in spatial memory in the elderly is often underestimated, and it is crucial to fully investigate the cognitive underpinnings of early spatial impairment. A virtual reality-based procedure was developed to assess deficit in the "mental frame syncing", namely the cognitive ability that allows an effective orientation by synchronizing the allocentric view-point independent representation with the allocentric view-point dependent representation. A pilot study was carried out to evaluate abilities in the mental frame syncing in a sample of 16 elderly participants. Preliminary results indicated that the general cognitive functioning was associated with the ability in the synchronization between these two allocentric references frames.

An Enhanced Biometric Based Authentication with Key-Agreement Protocol for Multi-Server Architecture Based on Elliptic Curve Cryptography

PubMed Central

Reddy, Alavalapati Goutham; Das, Ashok Kumar; Odelu, Vanga; Yoo, Kee-Young

2016-01-01

Biometric based authentication protocols for multi-server architectures have gained momentum in recent times due to advancements in wireless technologies and associated constraints. Lu et al. recently proposed a robust biometric based authentication with key agreement protocol for a multi-server environment using smart cards. They claimed that their protocol is efficient and resistant to prominent security attacks. The careful investigation of this paper proves that Lu et al.’s protocol does not provide user anonymity, perfect forward secrecy and is susceptible to server and user impersonation attacks, man-in-middle attacks and clock synchronization problems. In addition, this paper proposes an enhanced biometric based authentication with key-agreement protocol for multi-server architecture based on elliptic curve cryptography using smartcards. We proved that the proposed protocol achieves mutual authentication using Burrows-Abadi-Needham (BAN) logic. The formal security of the proposed protocol is verified using the AVISPA (Automated Validation of Internet Security Protocols and Applications) tool to show that our protocol can withstand active and passive attacks. The formal and informal security analyses and performance analysis demonstrates that the proposed protocol is robust and efficient compared to Lu et al.’s protocol and existing similar protocols. PMID:27163786

Timing of follicular phase events and the postovulatory progesterone rise following synchronisation of oestrus in cows.

PubMed

Starbuck, G R; Gutierrez, C G; Peters, A R; Mann, G E

2006-07-01

In cows the timing of both ovulation and the subsequent postovulatory progesterone rise are critical to successful fertilisation and early embryo development. The aim of this study was to determine the degree of variability in the timing of ovulation relative to other follicular phase events and to determine how variations in the timing of follicular phase events contribute to the timing of the postovulatory progesterone rise. Plasma concentrations of progesterone, oestradiol and luteinising hormone (LH) and the timing of oestrus and ovulation were determined following induction of luteolysis were determined in 18 mature, non-lactating Holstein-Friesian cows. Four cows were excluded on the basis of abnormal reproductive function. In the remaining 14 cows oestrus occurred at 57.4+/-4.3h and the LH surge at 54.6+/-4.0h following luteolysis (progesterone <1ngmL(-1)) followed by a fall in circulating oestradiol concentration at 64.6+/-4.4h. Cows ovulated at 88.0+/-4.7h with the postovulatory progesterone rise (to >1ngmL(-1)) occurring 159+/-7.2h after luteolysis. There was considerable variation in the timing of ovulation following luteolysis (range 64-136h) onset of oestrus (range 24-40h) and onset of the LH surge (range 24-44h). Cows were then split on the basis of interval from progesterone fall to progesterone rise giving groups (n=7 per group) with intervals of 180.6+/-6.7 and 138.3+/-5.7h (P<0.001). Between groups, both the intervals from luteolysis to ovulation (98.3+/-6.9 vs 77.7+/-3.4h; P<0.05) and ovulation to progesterone rise (82.3+/-4.2 vs. 60.6+/-5.5h; P<0.01) were longer in late rise cows. There was no difference between groups in the interval from oestrus or LH surge to ovulation. In conclusion the results of this study further highlight the high variability that exists in the timing and interrelationships of follicular phase events in the modern dairy cow, reemphasising the challenges that exist in optimising mating strategies. However, the data do suggest that in cows with poor post ovulatory progesterone secretion, the key problem appears to be poor post ovulatory development rather than a delay in ovulation.

Non-reproductive Effects of Anovulation

PubMed Central

Niethammer, B.; Körner, C.; Schmidmayr, M.; Luppa, P. B.; Seifert-Klauss, V. R.

2015-01-01

Introduction: Several authors have linked subclinical ovulatory disturbances in normal length menstrual cycles to premenopausal fracture risk and bone changes. This study systematically examined the influence of ovulation and anovulation on the bone metabolism of premenopausal women. Participants and Methods: In 176 cycles in healthy premenopausal women, FSH, 17β-estradiol (E2) and progesterone (P4) as well as bone alkalic phosphatase (BAP), pyridinoline (PYD) and C-terminal crosslinks (CTX) were measured during the follicular and during the luteal phase. The probability and timing of ovulation was self-assessed by a monitoring device. In addition, bone density of the lumbar spine was measured by quantitative computed tomography (QCT) at baseline and at the end of the study. Analysis was restricted to blood samples taken more than three days before the following menstruation. Results: 118 cycles out of the 176 collected cycles were complete with blood samples taken within the correct time interval. Of these, 56.8 % were ovulatory by two criteria (ovulation symbol shown on the monitor display and LP progesterone > 6 ng/ml), 33.1 % were possibly ovulatory by one criterion (ovulation symbol shown on the monitor display or LP progesterone > 6 ng/ml), and 10.2 % were anovulatory by both criteria). Ovulation in the previous cycle and in the same cycle did not significantly influence the mean absolute concentrations of the bone markers. However, bone formation (BAP) was higher in the luteal phase of ovulatory cycles than in anovulatory cycles (n. s.) and the relative changes within one cycle were significantly different for bone resorption (CTX) during ovulatory vs. anovulatory cycles (p < 0.01). In 68 pairs of cycles following each other directly, both ovulation in the previous cycle and ovulation in the present cycle influenced CTX, but not the differences of other bone markers. Conclusion: Ovulatory cycles reduce bone resorption in their luteal phase and that of the following cycle. The interaction between ovulation and bone metabolism is complex. Since anovulation may occur in low estrogen states such as pre-anorexic dietary restraint, as well as with high estrogenic circumstances e.g. from functional perimenopausal ovarian cysts, the association with bone changes has been variable in the literature. Accumulating physiological and clinical evidence however point towards a role for ovulation in enhancing bone formation and limiting bone resorption. PMID:26726266

Exposure to bisphenol A in young adult mice does not alter ovulation but does alter the fertilization ability of oocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moore-Ambriz, Teresita Rocio; Acuña-Hernández, Deyanira Guadalupe; Ramos-Robles, Brenda

Follicle growth culminates in ovulation, which allows for the expulsion of fertilizable oocytes and the formation of corpora lutea. Bisphenol A (BPA) is present in many consumer products, and it has been suggested that BPA impairs ovulation; however, the underlying mechanisms are unknown. Therefore, this study first evaluated whether BPA alters ovulation by affecting folliculogenesis, the number of corpora lutea or eggs shed to the oviduct, ovarian gonadotropin responsiveness, hormone levels, and estrous cyclicity. Because it has been suggested (but not directly confirmed) that BPA exerts toxic effects on the fertilization ability of oocytes, a second aim was to evaluatemore » whether BPA impacts the oocyte fertilization rate using an in vitro fertilization assay and mating. The possible effects on early zygote development were also examined. Young adult female C57BL/6J mice (39 days old) were orally dosed with corn oil (vehicle) or 50 μg/kg bw/day BPA for a period encompassing the first three reproductive cycles (12–15 days). BPA exposure did not alter any parameters related to ovulation. Moreover, BPA exposure reduced the percentage of fertilized oocytes after either in vitro fertilization or mating, but it did not alter the zygotic stages. The data indicate that exposure to the reference dose of BPA does not impact ovulation but that it does influence the oocyte quality in terms of its fertilization ability. - Highlights: • Bisphenol A targets the fertilization ability of oocytes. • Bisphenol A does not alter ovulation. • Young adult females may be susceptible to the effects of bisphenol A on fertilization.« less

Endometrial Shedding Effect on Conception and Live Birth in Women With Polycystic Ovary Syndrome

PubMed Central

Diamond, Michael P.; Kruger, Michael; Santoro, Nanette; Zhang, Heping; Casson, Peter; Schlaff, William; Coutifaris, Christos; Brzyski, Robert; Christman, Gregory; Carr, Bruce R.; McGovern, Peter G.; Cataldo, Nicholas A.; Steinkampf, Michael P.; Gosman, Gabriella G.; Nestler, John E.; Carson, Sandra; Myers, Evan E.; Eisenberg, Esther; Legro, Richard S.

2013-01-01

Objective To estimate whether progestin-induced endometrial shedding, prior to ovulation induction with clomiphene citrate, metformin, or a combination of both, affects ovulation, conception, and live birth rates in women with polycystic ovary syndrome (PCOS). Methods A secondary analysis of the data from 626 women with PCOS from the National Institutes of Child Health and Human Development Cooperative Reproductive Medicine Network trial was performed. Women had been randomized to up to six cycles of clomiphene citrate alone, metformin alone, or clomiphene citrate plus metformin. Women were assessed for occurrence of ovulation, conception, and live birth in relation to prior bleeding episodes (after either ovulation or exogenous progestin-induced withdrawal bleed). Results While ovulation rates were higher in cycles preceded by spontaneous endometrial shedding than after anovulatory cycles (with or without prior progestin withdrawal), both conception and live birth rates were significantly higher after anovulatory cycles without progestin-induced withdrawal bleeding (live birth per cycle: spontaneous menses 2.2%; anovulatory with progestin withdrawal 1.6%; anovulatory without progestin withdrawal 5.3%; p<0.001). The difference was more marked when rate was calculated per ovulation (live birth per ovulation: spontaneous menses 3.0%; anovulatory with progestin withdrawal 5.4%; anovulatory without progestin withdrawal 19.7%; p < .001). Conclusion Conception and live birth rates are lower in women with PCOS after a spontaneous menses or progestin-induced withdrawal bleeding as compared to anovulatory cycles without progestin withdrawal. The common clinical practice of inducing endometrial shedding with progestin prior to ovarian stimulation may have an adverse effect on rates of conception and live birth in anovulatory women with PCOS. PMID:22525900

Pretreatment and co-administration of oral anti-diabetic agent with clomiphene citrate or rFSH for ovulation induction in clomiphene-citrate-resistant polycystic ovary syndrome.

PubMed

Begum, Mosammat Rashida; Akhter, Sayeba; Ehsan, Mariya; Begum, Mosammat Shahina; Khan, Farzana

2013-05-01

The objective of this study was to explore the result of pretreatment and concomitant use of metformin with clomiphene citrate (CC) and rFSH for ovulation induction in clomiphene-citrate-resistant polycystic ovary syndrome (PCOS). This randomized controlled trial was done in the Dhaka Medical College and Hospital and the Infertility Care and Research Centre, Dhaka, Bangladesh. A total of 165 infertile patients with CC-resistant PCOS who attended for treatment were the target population for this study. Patients were divided into three groups: groups A and B were given metformin and group C was the control. Along with metformin, group A received CC and group B received rFSH. Group C was treated with only rFSH. Metformin was given 1500 mg daily for 4 weeks. Afterwards CC or rFSH were added for induction of ovulation along with metformin. Six ovulatory cycles were assessed. Treatment was terminated when there was no response with maximum dose of CC and rFSH or after six ovulatory cycles without pregnancy or after achieving pregnancy. A P-value of <0.5 was considered as significant. Ovulation (89.09%) and pregnancy (54.55%) rates were higher in group B. Ovulation (74.55%) and pregnancy (29.09%) rates were also satisfactory in group C but a dose of rFSH requirement was significantly higher (P = 0.000). In group A, both ovulation and pregnancy rate were much lower than the other two groups (27.27% and 12.73%, respectively). Use of metformin increases the response of ovulation-inducing agents and can be used safely in PCOS. © 2013 The Authors. Journal of Obstetrics and Gynaecology Research © 2013 Japan Society of Obstetrics and Gynecology.

Ovule identity mediated by pre-mRNA processing in Arabidopsis

PubMed Central

Rodríguez-Cazorla, Encarnación; Candela, Héctor; Bailey-Steinitz, Lindsay J.; Yanofsky, Martin F.; Martínez-Laborda, Antonio

2018-01-01

Ovules are fundamental for plant reproduction and crop yield as they are the precursors of seeds. Therefore, ovule specification is a critical developmental program. In Arabidopsis thaliana, ovule identity is redundantly conferred by the homeotic D-class genes SHATTERPROOF1 (SHP1), SHP2 and SEEDSTICK (STK), phylogenetically related to the MADS-domain regulatory gene AGAMOUS (AG), essential in floral organ specification. Previous studies have shown that the HUA-PEP activity, comprised of a suite of RNA-binding protein (RBP) encoding genes, regulates AG pre-mRNA processing and thus flower patterning and organ identity. Here, we report that the HUA-PEP activity additionally governs ovule morphogenesis. Accordingly, in severe hua-pep backgrounds ovules transform into flower organ-like structures. These homeotic transformations are most likely due to the dramatic reduction in SHP1, SHP2 and STK activity. Our molecular and genome-wide profiling strategies revealed the accumulation of prematurely terminated transcripts of D-class genes in hua-pep mutants and reduced amounts of their respective functional messengers, which points to pre-mRNA processing misregulation as the origin of the ovule developmental defects in such backgrounds. RNA processing and transcription are coordinated by the RNA polymerase II (RNAPII) carboxyl-terminal domain (CTD). Our results show that HUA-PEP activity members can interact with the CTD regulator C-TERMINAL DOMAIN PHOSPHATASE-LIKE1 (CPL1), supporting a co-transcriptional mode of action for the HUA-PEP activity. Our findings expand the portfolio of reproductive developmental programs in which HUA-PEP activity participates, and further substantiates the importance of RNA regulatory mechanisms (pre-mRNA co-transcriptional regulation) for correct gene expression during plant morphogenesis. PMID:29329291

Optical slotted circuit switched network: a bandwidth efficient alternative to wavelength-routed network

NASA Astrophysics Data System (ADS)

Li, Yan; Collier, Martin

2007-11-01

Wavelength-routed networks have received enormous attention due to the fact that they are relatively simple to implement and implicitly offer Quality of Service (QoS) guarantees. However, they suffer from a bandwidth inefficiency problem and require complex Routing and Wavelength Assignment (RWA). Most attempts to address the above issues exploit the joint use of WDM and TDM technologies. The resultant TDM-based wavelength-routed networks partition the wavelength bandwidth into fixed-length time slots organized as a fixed-length frame. Multiple connections can thus time-share a wavelength and the grooming of their traffic leads to better bandwidth utilization. The capability of switching in both wavelength and time domains in such networks also mitigates the RWA problem. However, TMD-based wavelength-routed networks work in synchronous mode and strict synchronization among all network nodes is required. Global synchronization for all-optical networks which operate at extremely high speed is technically challenging, and deploying an optical synchronizer for each wavelength involves considerable cost. An Optical Slotted Circuit Switching (OSCS) architecture is proposed in this paper. In an OSCS network, slotted circuits are created to better utilize the wavelength bandwidth than in classic wavelength-routed networks. The operation of the protocol is such as to avoid the need for global synchronization required by TDM-based wavelength-routed networks.

Synchronization of Mammalian Cells and Nuclei by Centrifugal Elutriation.

PubMed

Banfalvi, Gaspar

2017-01-01

Synchronized populations of large numbers of cells can be obtained by centrifugal elutriation on the basis of sedimentation properties of small round particles, with minimal perturbation of cellular functions. The physical characteristics of cell size and sedimentation velocity are operative in the technique of centrifugal elutriation also known as counterstreaming centrifugation. The elutriator is an advanced device for increasing the sedimentation rate to yield enhanced resolution of cell separation. A random population of cells is introduced into the elutriation chamber of an elutriator rotor running in a specially designed centrifuge. By increasing step-by-step the flow rate of the elutriation fluid, successive populations of relatively homogeneous cell size can be removed from the elutriation chamber and used as synchronized subpopulations. For cell synchronization by centrifugal elutriation, early log S phase cell populations are most suitable where most of the cells are in G1 and S phase (>80 %). Apoptotic cells can be found in the early elutriation fractions belonging to the sub-Go window. Protocols for the synchronization of nuclei of murine pre-B cells and high-resolution centrifugal elutriation of CHO cells are given. The verification of purity and cell cycle positions of cells in elutriated fractions includes the measurement of DNA synthesis by [ 3 H]-thymidine incorporation and DNA content by propidium iodide flow cytometry.

Treatment strategies and cumulative live birth rates in WHO-II ovulation disorders.

PubMed

Braam, Sanne C; de Bruin, Jan Peter; Buisman, Erato T I A; Brandes, Monique; Nelen, Willianne L D M; Smeenk, Jesper M J; van der Steeg, Jan Willem; Mol, Ben Willem J; Hamilton, Carl J C M

2018-04-10

To assess the live birth rate in women with WHO II anovulation and the proportion of women that need second or third line treatments if the initial therapy fails. In this multicenter cohort study we included couples with unfulfilled child wish who were referred to three fertility clinics in the Netherlands and selected women with a WHO II ovulation disorder as the only final infertility diagnosis (n = 468). The cumulative live birth rate of the total group was 82% (383/468). The majority started with clomiphene-citrate as first-line treatment (n = 378) resulting in 180 (48%) live births. There were 153 couples (40%) who underwent a second-line treatment (recombinant-FSH or laparoscopic electrocoagulation of the ovaries, LEO) and 52 couples (14%) a third-line treatment (IVF/ICSI), resulting in 44% and 63% treatment dependent live births rates, respectively. Of all couples, 92 (20%) conceived naturally, 186 (40%) after clomiphene-citrate, 60 (13%) after recombinant-FSH, nine (2%) after LEO and 36 (8%) after IVF. Subfertile women with a WHO II ovulation disorder have a good prognosis on live birth, and most did so after ovulation induction with clomiphene-citrate. If first-line ovulation induction has failed ovulation induction with gonadotrophins or IVF still result in a live birth in about half of the cases. Copyright © 2018 Elsevier B.V. All rights reserved.

[Effect of clomiphene citrate and Dingkun Dan on ovulation induction and clinical pregnancy of polycystic ovary syndrome].

PubMed

Chen, Lan; Tan, Yong; Chen, Shu-Ping

2017-10-01

The evaluation is based on clomiphene citrate (CC)+gonadotropin (Gn), clinical study on CC and Dingkun Dan's treatment on ovulation induction and clinical pregnancy effect of PCOS, and to provide ideas and methods for traditional Chinese medicine assisted reproductive treatment. This study selected 60 PCOS infertility patients treated with ovulation induction in reproductive medicine clinic, Jiangsu Province Hospital of traditional Chinese medicine during 2015-10-01-2017-04-23. They were randomly divided into two groups： Group A (CC+Gn+HCG) and Group B (CC+Gn+Dingkun Dan). These results were observed and compared including cycle ovulation rate, cycle cancellation rate, cycle pregnancy rate, cumulative pregnancy rate, endometrial thickness, duration of Gn, total amount of Gn, the occurring rate of luteinized unruptured follicle syndrome and ovarian hyperstimulation syndrome. Group A had lower cycle ovulation rate, cycle pregnancy rate, cumulative pregnancy rate and endometrial thickness, compared with Group B, the difference was statistically significant(P＜0.05). However, Group A had higher cycle cancellation rate, duration of Gn and total amount of Gn, compared with Group B, the difference was statistically significant(P＜0.05). In this study, no case of LUFS or OHSS was found in all patients. CC and Dingkun Dan had the effect of promoting ovulation on PCOS infertility patients, and CC+Gn+Dingkun Dan could elevate clinical pregnancy rate. Copyright© by the Chinese Pharmaceutical Association.

Cardiac phase-synchronized myocardial thallium-201 single-photon emission tomography using list mode data acquisition and iterative tomographic reconstruction.

PubMed

Vemmer, T; Steinbüchel, C; Bertram, J; Eschner, W; Kögler, A; Luig, H

1997-03-01

The purpose of this study was to determine whether data acquisition in the list mode and iterative tomographic reconstruction would render feasible cardiac phase-synchronized thallium-201 single-photon emission tomography (SPET) of the myocardium under routine conditions without modifications in tracer dose, acquisition time, or number of steps of the a gamma camera. Seventy non-selected patients underwent 201T1 SPET imaging according to a routine protocol (74 MBq/2 mCi 201T1, 180 degrees rotation of the gamma camera, 32 steps, 30 min). Gamma camera data, ECG, and a time signal were recorded in list mode. The cardiac cycle was divided into eight phases, the end-diastolic phase encompassing the QRS complex, and the end-systolic phase the T wave. Both phase- and non-phase-synchronized tomograms based on the same list mode data were reconstructed iteratively. Phase-synchronized and non-synchronized images were compared. Patients were divided into two groups depending on whether or not coronary artery disease had been definitely diagnosed prior to SPET imaging. The numbers of patients in both groups demonstrating defects visible on the phase-synchronized but not on the non-synchronized images were compared. It was found that both postexercise and redistribution phase tomograms were suited for interpretation. The changes from end-diastolic to end-systolic images allowed a comparative assessment of regional wall motility and tracer uptake. End-diastolic tomograms provided the best definition of defects. Additional defects not apparent on non-synchronized images were visible in 40 patients, six of whom did not show any defect on the non-synchronized images. Of 42 patients in whom coronary artery disease had been definitely diagnosed, 19 had additional defects not visible on the non-synchronized images, in comparison to 21 of 28 in whom coronary artery disease was suspected (P < 0.02; chi 2). It is concluded that cardiac phase-synchronized 201T1 SPET of the myocardium was made feasible by list mode data acquisition and iterative reconstruction. The additional findings on the phase-synchronized tomograms, not visible on the non-synchronized ones, represented genuine defects. Cardiac phase-synchronized 201T1 SPET is advantageous in allowing simultaneous assessment of regional wall motion and tracer uptake, and in visualizing smaller defects.

DNA Damage Response Resulting from Replication Stress Induced by Synchronization of Cells by Inhibitors of DNA Replication: Analysis by Flow Cytometry.

PubMed

Halicka, Dorota; Zhao, Hong; Li, Jiangwei; Garcia, Jorge; Podhorecka, Monika; Darzynkiewicz, Zbigniew

2017-01-01

Cell synchronization is often achieved by transient inhibition of DNA replication. When cultured in the presence of such inhibitors as hydroxyurea, aphidicolin or excess of thymidine the cells that become arrested at the entrance to S-phase upon release from the block initiate progression through S then G 2 and M. However, exposure to these inhibitors at concentrations commonly used to synchronize cells leads to activation of ATR and ATM protein kinases as well as phosphorylation of Ser139 of histone H2AX. This observation of DNA damage signaling implies that synchronization of cells by these inhibitors is inducing replication stress. Thus, a caution should be exercised while interpreting data obtained with use of cells synchronized this way since they do not represent unperturbed cell populations in a natural metabolic state. This chapter critically outlines virtues and vices of most cell synchronization methods. It also presents the protocol describing an assessment of phosphorylation of Ser139 on H2AX and activation of ATM in cells treated with aphidicolin, as a demonstrative of one of several DNA replication inhibitors that are being used for cell synchronization. Phosphorylation of Ser139H2AX and Ser1981ATM in individual cells is detected immunocytochemically with phospho-specific Abs and intensity of immunofluorescence is measured by flow cytometry. Concurrent measurement of cellular DNA content followed by multiparameter analysis allows one to correlate the extent of phosphorylation of these proteins in response to aphidicolin with the cell cycle phase.

Clomiphene citrate combined with metformin versus letrozole for induction of ovulation in clomiphene-resistant polycystic ovary syndrome: a randomized clinical trial.

PubMed

Rezk, Mohamed; Shaheen, Abd-Elhamid; Saif El-Nasr, Ibrahim

2018-04-01

A total of 202 patients with clomiphene citrate (CC) -resistant polycystic ovary syndrome (PCOS) were randomly allocated into two arms of induction of ovulation; the first group (n = 102) received CC 100 mg and metformin 500 mg while the second group (n = 100) received letrozole 2.5 mg with ovulation rate, clinical pregnancy rate, adverse effects, and acceptability were assessed. Patients in the letrozole arm experienced higher rate of ovulation (82% versus 43.1%, p < .001), more dominant follicles (p < .05), better endometrial thickness (p < .001), higher clinical pregnancy rate (36% versus 9.8%, p < .001), higher multiple pregnancy rate (p < .05), lesser adverse effects (p < .05) and higher acceptability (p < .001) compared to patients in the CC and metformin arm. In conclusion; letrozole is better and more acceptable than combined CC and metformin for inducing ovulation in patients with CC-resistant PCOS with higher clinical pregnancy rate and unexpectedly higher multiple pregnancy rate.

Intravaginal metronidazole gel versus metronidazole plus nystatin ovules for bacterial vaginosis: a randomized controlled trial.

PubMed

Sanchez, Sixto; Garcia, Patricia J; Thomas, Katherine K; Catlin, Mary; Holmes, King K

2004-12-01

We compared metronidazole 0.75% gel (containing 37.5 mg metronidazole per dose) with ovules containing metronidazole 500 mg and nystatin 100,000 U, for intravaginal treatment of bacterial vaginosis (BV). In a single-blinded trial, symptomatic women with BV by both Amsel and Nugent criteria were randomly assigned to gel or ovules, once nightly for 5 nights, and asked to return 3 times after treatment. Analyses were intent-to-treat. Of 151 women with BV by both criteria at enrollment, 138 (91%) returned at least once. Product limit estimates for persistence or recurrence of BV at 14, 42, and 104 days were 20% (95% CI 10%-29%), 38% (95% CI 25%-48%), and 52% (95% CI 37%-63%) after gel treatment, and 4% (95% CI 0%-9%), 17% (95% CI 7%-26%), and 33% (95% CI 21%-46%) after ovule treatment ( P = .01). Among women without BV at first follow-up, subsequent intercourse without condoms independently predicted subsequent recurrence ( P

Steroid signaling in mature follicles is important for Drosophila ovulation

PubMed Central

Knapp, Elizabeth

2017-01-01

Although ecdysteroid signaling regulates multiple steps in oogenesis, it is not known whether it regulates Drosophila ovulation, a process involving a matrix metalloproteinase-dependent follicle rupture. In this study, we demonstrated that ecdysteroid signaling is operating in mature follicle cells to control ovulation. Moreover, knocking down shade (shd), encoding the monooxygenase that converts ecdysone (E) to the more active 20-hydroxyecdysone (20E), specifically in mature follicle cells, blocked follicle rupture, which was rescued by ectopic expression of shd or exogenous 20E. In addition, disruption of the Ecdysone receptor (EcR) in mature follicle cells mimicked shd-knockdown defects, which were reversed by ectopic expression of EcR.B2 but not by EcR.A or EcR.B1 isoforms. Furthermore, we showed that ecdysteroid signaling is essential for the proper activation of matrix metalloproteinase 2 (Mmp2) for follicle rupture. Our data strongly suggest that 20E produced in follicle cells before ovulation activates EcR.B2 to prime mature follicles to be responsive to neuronal ovulatory stimuli, thus providing mechanistic insights into steroid signaling in Drosophila ovulation. PMID:28069934

Regulation of the ovarian inflammatory response at ovulation by nuclear progesterone receptor.

PubMed

Akison, Lisa K; Robertson, Sarah A; Gonzalez, Macarena B; Richards, JoAnne S; Smith, C Wayne; Russell, Darryl L; Robker, Rebecca L

2018-06-01

The nuclear progesterone receptor (PGR) transcription factor is essential for ovulation; however, the exact mechanisms by which PGR controls ovulation are not known. The aim of this study was to determine whether PGR regulates inflammatory mediators in the ovary. Ovaries from mice lacking PGR (PRKO) and heterozygous PR+/- littermates were subjected to microarray analysis of a large panel of inflammatory genes. Immune cell subsets were detected by gene expression; and neutrophils by immunohistochemistry and chemotaxis assay. PRKO ovaries exhibited dysregulated expression of vasodilator (Edn1), cytokine (Il-6, Tgfb1), adhesion receptor (Cd34), apoptotic factor (Bax) and transcription factors (Nfkb2, Socs1, Stat3). Ptgs2 was also reduced in PRKO ovaries, but mRNA and protein were not different in granulosa cells. There were reduced neutrophils in ovaries of PRKO mice at ovulation; however, chemotaxis assays showed PRKO neutrophils migrate normally and that PRKO ovarian extracts exhibit chemotactic properties in vitro. Specific inflammatory mediators are altered in the ovaries of PRKO mice indicating that progesterone regulates features of inflammation at ovulation. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

GnRHa to trigger final oocyte maturation: a time to reconsider.

PubMed

Humaidan, P; Papanikolaou, E G; Tarlatzis, B C

2009-10-01

Recently GnRH antagonist protocols for the prevention of a premature LH surge were introduced, allowing final oocyte maturation to be triggered with a single bolus of a GnRH agonist (GnRHa). GnRHa is as effective as hCG for the induction of ovulation, and apart from the LH surge a FSH surge is also induced. Until recently, prospective randomized studies reported a poor clinical outcome when GnRHa was used to trigger final oocyte maturation in IVF/ICSI antagonist protocols, presumably due to a luteal phase deficiency, despite standard luteal phase supplementation with progesterone and estradiol. As GnRHa triggering of final oocyte maturation could possess advantages over hCG triggering in terms of a reduced if not eliminated risk of ovarian hyperstimulation syndrome (OHSS) and the retrieval of more mature oocytes, the challenge has been to rescue the luteal phase. In the literature now several studies report a luteal phase rescue with a reproductive outcome comparable to that of hCG induced final oocyte maturation. Although more research is needed, GnRHa triggering is now a valid alternative with potential benefits.

Real-Time System Verification by Kappa-Induction

NASA Technical Reports Server (NTRS)

Pike, Lee S.

2005-01-01

We report the first formal verification of a reintegration protocol for a safety-critical, fault-tolerant, real-time distributed embedded system. A reintegration protocol increases system survivability by allowing a node that has suffered a fault to regain state consistent with the operational nodes. The protocol is verified in the Symbolic Analysis Laboratory (SAL), where bounded model checking and decision procedures are used to verify infinite-state systems by k-induction. The protocol and its environment are modeled as synchronizing timeout automata. Because k-induction is exponential with respect to k, we optimize the formal model to reduce the size of k. Also, the reintegrator's event-triggered behavior is conservatively modeled as time-triggered behavior to further reduce the size of k and to make it invariant to the number of nodes modeled. A corollary is that a clique avoidance property is satisfied.

Effect of clomiphene citrate on endometrial thickness, ovulation, pregnancy and live birth in anovulatory women: systematic review and meta-analysis.

PubMed

Gadalla, M A; Huang, S; Wang, R; Norman, R J; Abdullah, S A; El Saman, A M; Ismail, A M; van Wely, M; Mol, B W J

2018-01-01

To compare the impact of clomiphene citrate (CC) vs other drug regimens on mid-cycle endometrial thickness (EMT), ovulation, pregnancy and live birth rates in women with World Health Organization (WHO) group II ovulatory disorders. We searched MEDLINE, EMBASE, Scopus, Web of Science, The Cochrane Central Register of Clinical Trials (CENTRAL) and the non-MEDLINE subset of PubMed from inception to December 2016 and cross-checked references of relevant articles. We included only randomized controlled trials (RCTs) comparing CC used alone vs other drug regimens for ovulation induction in women with WHO group II anovulation. Outcomes were mid-cycle EMT, ovulation, pregnancy and live birth rates. We pooled weighted mean differences (WMD) with 95% confidence intervals (CI) for continuous variables (EMT) and risk ratios (RR) with 95% CI for binary variables (ovulation, pregnancy and live birth rates). We retrieved 1718 articles of which 33 RCTs (4349 women, 7210 ovulation induction cycles) were included. In 15 RCTs that compared CC with letrozole, EMT was lower in the CC group (1957 women, 3892 cycles; WMD, -1.39; 95% CI, -2.27 to -0.51; I 2  = 100%), ovulation rates after CC and letrozole were comparable (1710 women, 3217 cycles; RR, 0.97; 95% CI, 0.90-1.04; I 2  = 47%), while CC led to a lower pregnancy rate (1957 women, 3892 cycles; RR, 0.78; 95% CI, 0.63-0.95; I 2  = 43%) and a lower live birth rate (RR, 0.70; 95% CI, 0.49-0.98; I 2  = 35%). In two RCTs that compared CC with CC plus metformin, EMT, ovulation and pregnancy rates were comparable (101 women, 140 cycles; WMD, -0.23; 95% CI, -0.92 to 0.45; I 2  = 78%; RR, 0.84; 95% CI, 0.67-1.06; I 2  = 0%; and RR, 0.79; 95% CI, 0.33-1.87; I 2  = 0%). In three studies that compared CC with CC plus N-acetyl cysteine (NAC), EMT was lower in the CC group (340 women, 300 cycles; WMD, -1.51; 95% CI, -1.98 to -1.04; I 2  = 45%). In two studies that compared CC with CC + nitric oxide (NO) donor, EMT was lower in the CC group (120 women, 304 cycles; WMD, -1.75; 95% CI, -2.08 to -1.41; I 2  = 0%). Compared with CC plus NO donor or NAC, CC showed statistically significant lower ovulation and pregnancy rates. Compared with tamoxifen in three studies, CC showed a tendency towards lower EMT (571 women, 844 cycles; WMD, -1.34; 95% CI, -2.70 to 0.01; I 2  = 96%) with comparable ovulation and pregnancy rates. In women with WHO group II ovulatory disorders, ovulation induction with CC might result in lower EMT than other ovulation induction regimens. Whether the lower EMT caused the lower pregnancy and live birth rates remains to be elucidated. Letrozole seems to be beneficial for these women. However, our findings should be interpreted with caution as the quality of evidence was very low. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

A Secure RFID Tag Authentication Protocol with Privacy Preserving in Telecare Medicine Information System.

PubMed

Li, Chun-Ta; Weng, Chi-Yao; Lee, Cheng-Chi

2015-08-01

Radio Frequency Identification (RFID) based solutions are widely used for providing many healthcare applications include patient monitoring, object traceability, drug administration system and telecare medicine information system (TMIS) etc. In order to reduce malpractices and ensure patient privacy, in 2015, Srivastava et al. proposed a hash based RFID tag authentication protocol in TMIS. Their protocol uses lightweight hash operation and synchronized secret value shared between back-end server and tag, which is more secure and efficient than other related RFID authentication protocols. Unfortunately, in this paper, we demonstrate that Srivastava et al.'s tag authentication protocol has a serious security problem in that an adversary may use the stolen/lost reader to connect to the medical back-end server that store information associated with tagged objects and this privacy damage causing the adversary could reveal medical data obtained from stolen/lost readers in a malicious way. Therefore, we propose a secure and efficient RFID tag authentication protocol to overcome security flaws and improve the system efficiency. Compared with Srivastava et al.'s protocol, the proposed protocol not only inherits the advantages of Srivastava et al.'s authentication protocol for TMIS but also provides better security with high system efficiency.

Robust Timing Synchronization in Aeronautical Mobile Communication Systems

NASA Technical Reports Server (NTRS)

Xiong, Fu-Qin; Pinchak, Stanley

2004-01-01

This work details a study of robust synchronization schemes suitable for satellite to mobile aeronautical applications. A new scheme, the Modified Sliding Window Synchronizer (MSWS), is devised and compared with existing schemes, including the traditional Early-Late Gate Synchronizer (ELGS), the Gardner Zero-Crossing Detector (GZCD), and the Sliding Window Synchronizer (SWS). Performance of the synchronization schemes is evaluated by a set of metrics that indicate performance in digital communications systems. The metrics are convergence time, mean square phase error (or root mean-square phase error), lowest SNR for locking, initial frequency offset performance, midstream frequency offset performance, and system complexity. The performance of the synchronizers is evaluated by means of Matlab simulation models. A simulation platform is devised to model the satellite to mobile aeronautical channel, consisting of a Quadrature Phase Shift Keying modulator, an additive white Gaussian noise channel, and a demodulator front end. Simulation results show that the MSWS provides the most robust performance at the cost of system complexity. The GZCD provides a good tradeoff between robustness and system complexity for communication systems that require high symbol rates or low overall system costs. The ELGS has a high system complexity despite its average performance. Overall, the SWS, originally designed for multi-carrier systems, performs very poorly in single-carrier communications systems. Table 5.1 in Section 5 provides a ranking of each of the synchronization schemes in terms of the metrics set forth in Section 4.1. Details of comparison are given in Section 5. Based on the results presented in Table 5, it is safe to say that the most robust synchronization scheme examined in this work is the high-sample-rate Modified Sliding Window Synchronizer. A close second is its low-sample-rate cousin. The tradeoff between complexity and lowest mean-square phase error determines the rankings of the Gardner Zero-Crossing Detector and both versions of the Early-Late Gate Synchronizer. The least robust models are the high and low-sample-rate Sliding Window Synchronizers. Consequently, the recommended replacement synchronizer for NASA's Advanced Air Transportation Technologies mobile aeronautical communications system is the high-sample-rate Modified Sliding Window Synchronizer. By incorporating this synchronizer into their system, NASA can be assured that their system will be operational in extremely adverse conditions. The quick convergence time of the MSWS should allow the use of high-level protocols. However, if NASA feels that reduced system complexity is the most important aspect of their replacement synchronizer, the Gardner Zero-Crossing Detector would be the best choice.

[Lactation and amenorrhea in women from the rural and urban areas of Yucatan].

PubMed

Canto-de Cetina, T; Polanco-Reyes, L; Vera-Gamboa, L

1993-09-01

Influence of environment and lactation patterns on amenorrhea duration and frequency of ovulation before the first menstrual bleeding postpartum are studied on a group of 100 women (half rural, half from urban areas). All subjects studied were highly motivated to breastfeed for prolonged periods. Results show a more prolonged amenorrhea, although not statistically significant, in those women from the rural zone. Ovulation frequency before the first vaginal bleeding was 14% none ovulated before six months.

An improved method for growing neurons: Comparison with standard protocols.

PubMed

Pozzi, Diletta; Ban, Jelena; Iseppon, Federico; Torre, Vincent

2017-03-15

Since different culturing parameters - such as media composition or cell density - lead to different experimental results, it is important to define the protocol used for neuronal cultures. The vital role of astrocytes in maintaining homeostasis of neurons - both in vivo and in vitro - is well established: the majority of improved culturing conditions for primary dissociated neuronal cultures rely on astrocytes. Our culturing protocol is based on a novel serum-free preparation of astrocyte - conditioned medium (ACM). We compared the proposed ACM culturing method with other two commonly used methods Neurobasal/B27- and FBS- based media. We performed morphometric characterization by immunocytochemistry and functional analysis by calcium imaging for all three culture methods at 1, 7, 14 and 60days in vitro (DIV). ACM-based cultures gave the best results for all tested criteria, i.e. growth cone's size and shape, neuronal outgrowth and branching, network activity and synchronization, maturation and long-term survival. The differences were more pronounced when compared with FBS-based medium. Neurobasal/B27 cultures were comparable to ACM for young cultures (DIV1), but not for culturing times longer than DIV7. ACM-based cultures showed more robust neuronal outgrowth at DIV1. At DIV7 and 60, the activity of neuronal network grown in ACM had a more vigorous spontaneous electrical activity and a higher degree of synchronization. We propose our ACM-based culture protocol as an improved and more suitable method for both short- and long-term neuronal cultures. Copyright © 2017 Elsevier B.V. All rights reserved.

Imaging of cardiac perfusion of free-breathing small animals using dynamic phase-correlated micro-CT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sawall, Stefan; Kuntz, Jan; Socher, Michaela

Purpose:Mouse models of cardiac diseases have proven to be a valuable tool in preclinical research. The high cardiac and respiratory rates of free breathing mice prohibit conventional in vivo cardiac perfusion studies using computed tomography even if gating methods are applied. This makes a sacrification of the animals unavoidable and only allows for the application of ex vivo methods. Methods: To overcome this issue the authors propose a low dose scan protocol and an associated reconstruction algorithm that allows for in vivo imaging of cardiac perfusion and associated processes that are retrospectively synchronized to the respiratory and cardiac motion ofmore » the animal. The scan protocol consists of repetitive injections of contrast media within several consecutive scans while the ECG, respiratory motion, and timestamp of contrast injection are recorded and synchronized to the acquired projections. The iterative reconstruction algorithm employs a six-dimensional edge-preserving filter to provide low-noise, motion artifact-free images of the animal examined using the authors' low dose scan protocol. Results: The reconstructions obtained show that the complete temporal bolus evolution can be visualized and quantified in any desired combination of cardiac and respiratory phase including reperfusion phases. The proposed reconstruction method thereby keeps the administered radiation dose at a minimum and thus reduces metabolic inference to the animal allowing for longitudinal studies. Conclusions: The authors' low dose scan protocol and phase-correlated dynamic reconstruction algorithm allow for an easy and effective way to visualize phase-correlated perfusion processes in routine laboratory studies using free-breathing mice.« less

Relation of supplementary feeding to resumptions of menstruation and ovulation in lactating postpartum women.

PubMed

Li, Wei; Qiu, Yi

2007-05-20

Resumption of menstrual cycles is one of the indicators for restoration of reproductive capability in postpartum women. However, menstruation does not necessarily mean that ovulation has taken place. The aim of this study was to investigate the relation of supplementary feeding to return of menstruation and ovulation after delivery. A questionnaire was used to obtain data from 101 breastfeeding mothers. The following elements were analyzed: age, education level, breastfeeding practice, time of return of menstruation, contraceptive practice, and starting time of supplementary feeding during the lactation at intervals of 6 weeks to 18 months after delivery. The ovulation was continuously monitored by ultrasonography and basal body temperature (BBT) measurement. By ultrasonography, 53 of the 101 women (52.5%) had the first ovulation (follicle > 1.8 cm in diameter) within 154 days after delivery on average, among whom 11 (10.9%, 11/101) had restoration of ovulation within 4 months and 42 (41.6%, 42/101) had it after 4 months. In women with follicles > 1.8 cm in diameter (n = 53), the menstruation resumed (138 +/- 84) days after delivery, and the supplementary feeding was started at (4.0 +/- 1.1) months, which were significantly earlier than those in the women with follicular diameter < 1.7 cm (n = 48; (293 +/- 88) days, (5.1 +/- 1.3) months; t = 9.003, P < 0.01 and t = 4.566, P < 0.01). In the women with follicles < 1.8 cm in diameter, 30 had return of menstruation before the end of ultrasonographic monitoring, while only 8 in the women with follicular diameter < 1.7 cm had menstrual resumption at the same time (chi(2) = 16.91, P < 0.01). The starting time of supplementary feeding was positively correlated with the time of the restoration of menstruation (n = 100, r = 0.4764, P < 0.01) and first ovulation after delivery (n = 53, r = 0.5554, P < 0.01). In this series, no woman had pregnancy within 18 months postpartum. Supplementary feeding can affect the restoration of menstrual cycles and ovulation in lactating postpartum women.

A Web-Free Prototype for Distance Learning.

ERIC Educational Resources Information Center

Molinari, Andrea; Colazzo, Luigi

This paper presents a prototype for the construction of interactive educational hypermedia that can be used on the Internet without being bound to typical World Wide Web protocols and tools. Its most innovative aspect is interactivity: it allows teachers and learners to remotely interact in real time in both a synchronous and asynchronous manner.…

A Self-Organizing Interaction and Synchronization Method between a Wearable Device and Mobile Robot

PubMed Central

Kim, Min Su; Lee, Jae Geun; Kang, Soon Ju

2016-01-01

In the near future, we can expect to see robots naturally following or going ahead of humans, similar to pet behavior. We call this type of robots “Pet-Bot”. To implement this function in a robot, in this paper we introduce a self-organizing interaction and synchronization method between wearable devices and Pet-Bots. First, the Pet-Bot opportunistically identifies its owner without any human intervention, which means that the robot self-identifies the owner’s approach on its own. Second, Pet-Bot’s activity is synchronized with the owner’s behavior. Lastly, the robot frequently encounters uncertain situations (e.g., when the robot goes ahead of the owner but meets a situation where it cannot make a decision, or the owner wants to stop the Pet-Bot synchronization mode to relax). In this case, we have adopted a gesture recognition function that uses a 3-D accelerometer in the wearable device. In order to achieve the interaction and synchronization in real-time, we use two wireless communication protocols: 125 kHz low-frequency (LF) and 2.4 GHz Bluetooth low energy (BLE). We conducted experiments using a prototype Pet-Bot and wearable devices to verify their motion recognition of and synchronization with humans in real-time. The results showed a guaranteed level of accuracy of at least 94%. A trajectory test was also performed to demonstrate the robot’s control performance when following or leading a human in real-time. PMID:27338384

A Self-Organizing Interaction and Synchronization Method between a Wearable Device and Mobile Robot.

PubMed

Kim, Min Su; Lee, Jae Geun; Kang, Soon Ju

2016-06-08

In the near future, we can expect to see robots naturally following or going ahead of humans, similar to pet behavior. We call this type of robots "Pet-Bot". To implement this function in a robot, in this paper we introduce a self-organizing interaction and synchronization method between wearable devices and Pet-Bots. First, the Pet-Bot opportunistically identifies its owner without any human intervention, which means that the robot self-identifies the owner's approach on its own. Second, Pet-Bot's activity is synchronized with the owner's behavior. Lastly, the robot frequently encounters uncertain situations (e.g., when the robot goes ahead of the owner but meets a situation where it cannot make a decision, or the owner wants to stop the Pet-Bot synchronization mode to relax). In this case, we have adopted a gesture recognition function that uses a 3-D accelerometer in the wearable device. In order to achieve the interaction and synchronization in real-time, we use two wireless communication protocols: 125 kHz low-frequency (LF) and 2.4 GHz Bluetooth low energy (BLE). We conducted experiments using a prototype Pet-Bot and wearable devices to verify their motion recognition of and synchronization with humans in real-time. The results showed a guaranteed level of accuracy of at least 94%. A trajectory test was also performed to demonstrate the robot's control performance when following or leading a human in real-time.

High frequency of luteal phase deficiency and anovulation in recreational women runners: blunted elevation in follicle-stimulating hormone observed during luteal-follicular transition.

PubMed

De Souza, M J; Miller, B E; Loucks, A B; Luciano, A A; Pescatello, L S; Campbell, C G; Lasley, B L

1998-12-01

The purposes of this investigation were to evaluate the characteristics of three consecutive menstrual cycles and to determine the frequency ofluteal phase deficiency (LPD) and anovulation in a sample of sedentary and moderately exercising, regularly menstruating women. For three consecutive menstrual cycles, subjects collected daily urine samples for analysis of FSH, estrone conjugates (E1C), pregnanediol-3-glucuronide (PdG), and creatinine (Cr). Sedentary (n=11) and exercising (n=24) groups were similar in age (27.0+/-1.3 yr), weight (60.3+/-3.1 kg), gynecological age (13.8+/-1.2 yr), and menstrual cycle length (28.3+/-0.8 days). Menstrual cycles were classified by endocrine data as ovulatory, LPD, or anovulatory. No sedentary women (0%) had inconsistent menstrual cycle classifications from cycle to cycle, but 46% of the exercising women were inconsistent. The sample prevalence of LPD in the exercising women was 48%, and the 3-month sample incidence was 79%. In the sedentary women, 90% of all menstrual cycles were ovulatory (SedOvul; n=28), whereas in the exercising women only 45% were ovulatory (ExOvul; n=30); 43% were LPD (ExLPD; n=28), and 12% were anovulatory (ExAnov; n=8). In ExLPD cycles, the follicular phase was significantly longer (17.9+/-0.7 days), and the luteal phase was significantly shorter (8.2+/-0.5 days) compared to ExOvul (14.8+/-0.9 and 12.9+/-0.3 days) and SedOvul (15.9+/-0.6 and 12.9+/-0.4 days) cycles. Luteal phase PdG excretion was lower (P < 0.001) in ExLPD (2.9+/-0.3 microg/mg Cr) and ExAnov (0.8+/-0.1 microg/mg Cr) cycles compared to SedOvul cycles (5.0+/-0.4 microg/mg Cr). ExOvul cycles also had less (P < 0.01) PdG excretion during the luteal phase (3.7+/-0.3 microg/mg Cr) than the SedOvul cycles. E1C excretion during follicular phase days 2-5 was lower (P=0.05) in ExOvul, ExLPD, and ExAnov cycles compared to SedOvul cycles and remained lower (P < 0.02) in the ExLPD and ExAnov cycles during days 6-12. The elevation in FSH during the luteal-follicular transition was lower (P < 0.007) in ExLPD (0.7+/-0.1 ng/mg Cr) cycles compared to SedOvul and ExOvul cycles (1.0+/-0.1 and 1.1+/-0.1 ng/mg Cr, respectively). Energy balance and energy availability were lower (P < 0.05) in ExAnov cycles than in other menstrual cycle categories. The blunted elevation in FSH during the luteal-follicular transition in exercising women with LPD may explain their lower follicular estradiol levels. These alterations in FSH may act in concert with disrupted LH pulsatility as a primary and proximate factor in the high frequency of luteal phase and ovulatory disturbances in regularly menstruating, exercising women.

Phosphatidylcholine catabolism in the MCF-7 cell cycle.

PubMed

Lin, Weiyang; Arthur, Gilbert

2006-10-01

The catabolism of phosphatidylcholine (PtdCho) appears to play a key role in regulating the net accumulation of the lipid in the cell cycle. Current protocols for measuring the degradation of PtdCho at specific cell-cycle phases require prolonged periods of incubation with radiolabelled choline. To measure the degradation of PtdCho at the S and G2 phases in the MCF-7 cell cycle, protocols were developed with radiolabelled lysophosphatidylcholine (lysoPtdCho), which reduces the labelling period and minimizes the recycling of labelled components. Although most of the incubated lysoPtdCho was hydrolyzed to glycerophosphocholine (GroPCho) in the medium, the kinetics of the incorporation of label into PtdCho suggests that the labelled GroPCho did not contribute significantly to cellular PtdCho formation. A protocol which involved exposing the cells twice to hydroxyurea, was also developed to produce highly synchronized MCF-7 cells with a profile of G1:S:G2/M of 90:5:5. An analysis of PtdCho catabolism in the synchronized cells following labelling with lysoPtdCho revealed that there was increased degradation of PtdCho in early to mid-S phase, which was attenuated in the G2/M phase. The results suggest that the net accumulation of PtdCho in MCF-7 cells may occur in the G2 phase of the cell cycle.

Prognostic value of total testosterone for pregnancy during treatment in patients with clomiphene-citrate-resistant polycystic ovary syndrome: a pilot study.

PubMed

Li, Chunyang; Cheng, Jing; Wang, Jianguang; Xue, Yamei; Huang, Zhaoxia; Zhang, Shengkun; Lv, Jieqiang

2011-09-01

Reduction of serum total testosterone (TT) is associated with pregnancy rate in polycystic ovary syndrome (PCOS) women receiving metformin, but most of the studies focus on the changes of basal levels of TT. The aim of this study was to evaluate whether the TT level around the ovulation period is related to the outcome of pregnancy in women with PCOS. In total, 30 non-obese PCOS women with clomiphene citrate (CC) resistance from the Medical College's Reproductive Health Center were enrolled and randomly assigned to be treated with placebo (Group 1) or metformin (850 mg) (Group 2) twice daily for 3 months as the pre-treatment. Then, metformin alone was administered with CC, human menopausal gonadotropin (HMG) and human chorionic gonadotropin (HCG) to induce ovulation for 3 months in Group 1. In Group 2, CC/HMG/HCG was used to induce ovulation for 3 months without metformin. Follicle-stimulating hormone, luteinizing hormone, estradiol and TT levels before and after ovulation in pregnant cycles and non-pregnant cycles were evaluated over the course of treatment. A total of 26 subjects completed 65 cycles. The TT levels after ovulation in the pregnant cycles were significantly lower than in the non-pregnant cycles in both groups (P = 0.001 and P < 0.001, respectively). The level of TT after ovulation may be of prognostic value for pregnancy in non-obese women with PCOS and CC resistance during treatment.

Perception of facial profiles: influence of female sex hormones and personality traits.

PubMed

Jovic, T; Pavlic, A; Varga, S; Kovacevic Pavicic, D; Slaj, M; Spalj, S

2016-11-01

The observational study investigated whether women's perception of the facial profile is related to changes in sex hormones during the menstrual cycle and under the influence of personality traits. Participants were heterosexual Caucasian normally menstruating women not using oral contraceptives (N = 30, aged 20-44 years). The profile attractiveness was assessed by grading of thirteen men's and women's Caucasian profile distortions by a visual analogue scale (0 = least to 100 = most attractive) in the non-ovulating phase and ovulating phase of the menstrual cycle. Male profiles were graded twice-in social and emotional contexts. Personality traits were assessed by Big Five Inventory. The most attractive male profiles in both phases and contexts were a straight profile or mild lip retrusion. According to cluster analysis, non-ovulating females distinguish skeletal from dentoalveolar alterations; however, maxillary retrognathism was considered to be closer to an attractive profile, which were resulting from dentoalveolar manipulations only. Ovulating females, when considering emotional relationship, exhibit lowest preference for males with convex profiles and extreme concave profile, while they consider males with slightly prominent chins due to maxillary retrognathism, mandibular prognathism or pronounced lip retrusion closer to the most attractive males. No clear patterns of influence of personality traits were detected. Moderate lip protrusion was the most attractive female profile in ovulating and straight profile in non-ovulating phase. The favorable profiles, on average, are the same regardless of the female hormonal status and personality traits. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Ca2+-induced uncoupling of Aplysia bag cell neurons.

PubMed

Dargaei, Zahra; Standage, Dominic; Groten, Christopher J; Blohm, Gunnar; Magoski, Neil S

2015-02-01

Electrical transmission is a dynamically regulated form of communication and key to synchronizing neuronal activity. The bag cell neurons of Aplysia are a group of electrically coupled neuroendocrine cells that initiate ovulation by secreting egg-laying hormone during a prolonged period of synchronous firing called the afterdischarge. Accompanying the afterdischarge is an increase in intracellular Ca2+ and the activation of protein kinase C (PKC). We used whole cell recording from paired cultured bag cell neurons to demonstrate that electrical coupling is regulated by both Ca2+ and PKC. Elevating Ca2+ with a train of voltage steps, mimicking the onset of the afterdischarge, decreased junctional current for up to 30 min. Inhibition was most effective when Ca2+ entry occurred in both neurons. Depletion of Ca2+ from the mitochondria, but not the endoplasmic reticulum, also attenuated the electrical synapse. Buffering Ca2+ with high intracellular EGTA or inhibiting calmodulin kinase prevented uncoupling. Furthermore, activating PKC produced a small but clear decrease in junctional current, while triggering both Ca2+ influx and PKC inhibited the electrical synapse to a greater extent than Ca2+ alone. Finally, the amplitude and time course of the postsynaptic electrotonic response were attenuated after Ca2+ influx. A mathematical model of electrically connected neurons showed that excessive coupling reduced recruitment of the cells to fire, whereas less coupling led to spiking of essentially all neurons. Thus a decrease in electrical synapses could promote the afterdischarge by ensuring prompt recovery of electrotonic potentials or making the neurons more responsive to current spreading through the network. Copyright © 2015 the American Physiological Society.

Preparation of TPP-crosslinked chitosan microparticles by spray drying for the controlled delivery of progesterone intended for estrus synchronization in cattle.

PubMed

Helbling, Ignacio M; Busatto, Carlos A; Fioramonti, Silvana A; Pesoa, Juan I; Santiago, Liliana; Estenoz, Diana A; Luna, Julio A

2018-02-20

Planned reproduction in cattle involves regulation of estrous cycle and the use of artificial insemination. Cycle control includes the administration of exogenous progesterone during 5-8 days in a controlled manner allowing females to synchronize their ovulation. Several progesterone delivery systems are commercially available but they have several drawbacks. The aim of the present contribution was to evaluate chitosan microparticles entrapping progesterone as an alternative system. Microparticles were prepared by spray drying. The effect of formulation parameters and experimental conditions on particle features and delivery was studied. A mathematical model to predict progesterone plasma concentration in animals was developed and validated with experimental data. Microparticle size was not affected by formulation parameters but sphericity enhances as Tween 80 content increases and it impairs as TPP content rises. Z potential decreases as phosphate content rises. Particles remain stable in acidic solution but the addition of surfactant is required to stabilize dispersions in neutral medium. Encapsulation efficiencies was 69-75%. In vitro delivery studies showed burst and diffusion-controlled phases, being progesterone released faster at low pH. In addition, delivery extend in cows was affected mainly by particle size and hormone initial content, while the amount injected altered plasma concentration. Theoretical predictions with excellent accuracy were obtained. The mathematical model developed can help to find proper particle features to reach specific delivery rates in the animals. This not only save time, money and effort but also minimized experimentation with animals which is desired from an ethical point of view.

Non-reproductive Effects of Anovulation: Bone Metabolism in the Luteal Phase of Premenopausal Women Differs between Ovulatory and Anovulatory Cycles.

PubMed

Niethammer, B; Körner, C; Schmidmayr, M; Luppa, P B; Seifert-Klauss, V R

2015-12-01

Introduction: Several authors have linked subclinical ovulatory disturbances in normal length menstrual cycles to premenopausal fracture risk and bone changes. This study systematically examined the influence of ovulation and anovulation on the bone metabolism of premenopausal women. Participants and Methods: In 176 cycles in healthy premenopausal women, FSH, 17β-estradiol (E2) and progesterone (P4) as well as bone alkalic phosphatase (BAP), pyridinoline (PYD) and C-terminal crosslinks (CTX) were measured during the follicular and during the luteal phase. The probability and timing of ovulation was self-assessed by a monitoring device. In addition, bone density of the lumbar spine was measured by quantitative computed tomography (QCT) at baseline and at the end of the study. Analysis was restricted to blood samples taken more than three days before the following menstruation. Results: 118 cycles out of the 176 collected cycles were complete with blood samples taken within the correct time interval. Of these, 56.8 % were ovulatory by two criteria (ovulation symbol shown on the monitor display and LP progesterone > 6 ng/ml), 33.1 % were possibly ovulatory by one criterion (ovulation symbol shown on the monitor display or LP progesterone > 6 ng/ml), and 10.2 % were anovulatory by both criteria). Ovulation in the previous cycle and in the same cycle did not significantly influence the mean absolute concentrations of the bone markers. However, bone formation (BAP) was higher in the luteal phase of ovulatory cycles than in anovulatory cycles (n. s.) and the relative changes within one cycle were significantly different for bone resorption (CTX) during ovulatory vs. anovulatory cycles (p < 0.01). In 68 pairs of cycles following each other directly, both ovulation in the previous cycle and ovulation in the present cycle influenced CTX, but not the differences of other bone markers. Conclusion: Ovulatory cycles reduce bone resorption in their luteal phase and that of the following cycle. The interaction between ovulation and bone metabolism is complex. Since anovulation may occur in low estrogen states such as pre-anorexic dietary restraint, as well as with high estrogenic circumstances e.g. from functional perimenopausal ovarian cysts, the association with bone changes has been variable in the literature. Accumulating physiological and clinical evidence however point towards a role for ovulation in enhancing bone formation and limiting bone resorption.

Suppression of ovulation by a new subcutaneous depot medroxyprogesterone acetate (104 mg/0.65 mL) contraceptive formulation in Asian women.

PubMed

Toh, Yeong Cheng; Jain, John; Rahnny, Mohamad H; Bode, Frederick R; Ross, Doug

2004-11-01

A new progestin-only, nondaily depot medroxyprogesterone acetate (DMPA) SC injectable contraceptive suspension (104 mg/0.65 mL) has been developed. Clinical trials (including dose-ranging, pharmacokinetic/pharmacodynamic, and contraceptive efficacy studies) indicating the effectiveness of this new formulation were conducted primarily in white women. However, results of an early study by the World Health Organization suggested that in Thai women, medroxyprogesterone acetate (MPA) may be metabolized in <91 +/- 7 days (the range for effective suppression of ovulation established in clinical trials), resulting in a faster return to ovulation in this population. This study was designed to determine the duration of ovulation suppression and investigate the pharmacokinetic profile of MPA after a single SC injection of DMPA 104 mg/0.65 mL in Asian women. It also assessed the effect of ethnicity and injection site on the duration of ovulation suppression. : This was a single-center, single-dose, open-label outpatient trial conducted in Singapore in Asian women aged 18 to 40 years. After 1 control cycle, women with confirmed ovulation were randomized in a 1:1 ratio to receive an SC injection of DMPA 104 mg/0.65 mL in either the anterior thigh or the abdomen. Serum concentrations of MPA, progesterone, estradiol, luteinizing hormone, and follicle-stimulating hormone were measured during the 91-day dosing interval and for an additional 15 days thereafter. Twenty-four Asian women (mean [SD] age, 33.8 [43] years; range, 22.7-40.1 years; mean [SD] body mass index, 22.4 [3.0] kg/m(2)) belonging to 5 ethnic groups (Chinese, Filipino, Indian, Malaysian, and Thai) were included in the study Ovulation suppression was maintained throughout the 91-day dosing interval, regardless of ethnicity or injection site. Ovulation was suppressed for at least 112 days after injection in 23 (95.8%) women, as evidenced by maintenance of serum progesterone concentrations <4.7 ng/mL. The pharmacokinetic parameters for MPA in these Asian women were similar to those previously reported in white women. The most frequently reported adverse events were flulike symptoms and headache, all of mild to moderate intensity. No serious adverse events were reported. In this study, SC DMPA 104 mg/0.65 mL provided effective suppression of ovulation for at least 91 days in Asian women. Ethnicity and injection site had no effect on MPA profiles.

Gynogenesis in the vine cacti Hylocereus and Selenicereus (Cactaceae).

PubMed

Garcia, Reinerio Benega; Cisneros, Aroldo; Schneider, Bert; Tel-Zur, Noemi

2009-05-01

Gynogenesis was investigated on the allotetraploid Selenicereus megalanthus and the diploid Hylocereus polyrhizus and Hylocereus undatus vine cactus species. Unpollinated ovules from developing flower buds containing microspores at middle uninucleate developmental stage were cultured on MS basal medium containing 2,4-D/TDZ with different sucrose concentrations. Ovule size increased under dark culture conditions in all the three species and the level of response was species and sucrose concentration dependent. The best responses were achieved in the two S. megalanthus accessions, E-123 and J-80, at 0.18 and 0.26 M sucrose. Only ovule enlargement was obtained in H. undatus and both ovule enlargement and callus were obtained in H. polyrhizus. Development in both species ceased and embryoids were not formed. Plant regeneration was directly and indirectly obtained in both S. megalanthus accessions. Ploidy level was determined for a total of 29 S. megalanthus gynogenic plants using flow cytometry: 15 were found to be dihaploid (plants with the gametophytic chromosome number) and the other 14 were found to have higher ploidy levels. This is the first report of successful gynogenesis in Cactaceae. The dihaploids of S. megalanthus successfully produced by ovule culture techniques opens new perspectives in vine cacti breeding.

Physiological mechanisms associated with ovulation prediction using the CUE Ovulation Predictor.

PubMed

Fernando, R S; Regas, J; Betz, G

1988-05-01

It has been shown that monitoring of salivary electrical resistance (SR) enables prediction of ovulation several days in advance, since a peak in SR is seen 5-6 days before the LH peak. This paper explores physiological mechanisms that may account for this change. The pathway whereby oestrogen stimulates aldosterone (ALDO) secretion acting through the renin-angiotensin system was considered. It is shown that this mechanism would only result in increasing SR as oestrogen values rise during the follicular phase and therefore is not an explanation of the SR peak and declining SR 5-6 days before the LH peak. The reported trend of sodium in milk of ovulating women parallels that of SR. It is shown that these changes are most likely to be due to a similar change in aldosterone levels. A possible role for adrenocorticotrophic hormone (ACTH) in causing the changes in aldosterone is discussed and supported with data from other independent studies as well as with preliminary data obtained from two normally ovulating subjects. Peaks in ACTH, ALDO and SR were coincidental and occurred 6 days before the LH peak. The temporal relationship observed among these variables suggest that ACTH, by affecting ALDO, modifies salivary electrolytes and hence SR.

Coevolution of female ovulatory signals and male-male competition in primates.

PubMed

Nakahashi, Wataru

2016-03-07

Visual signals of ovulation vary among primate species. Although slight ovulatory signals are considered primate ancestral traits of which some species still exhibit, some show prominent swelling of their perineal skin (exaggerated sexual swellings) and others do not exhibit any signals of ovulation (concealed ovulation). These signals strongly affect male mating behaviors. I develop an evolutionary model of female ovulatory signals and male-male competition. I assume that each male allocates his effort between attraction of females and male-male competition for dominance. Each female gains a benefit if she is fertile and free from the alpha male who always guards one of the most fertile females in the group, but suffers a cost if she expresses a different ovulatory signal from an ancestral trait. I show that various types of ovulatory signals may evolve and can be multistable. Male-male competition becomes intense when the signal honestly indicates ovulation. Ovulatory signals may evolve to be less exaggerated in unimale groups than in multimale groups and monogamy is more likely to evolve when ovulation is concealed. These results may partly explain why various types of primate ovulatory signals evolved and how they have affected primate societies. Copyright © 2015 Elsevier Ltd. All rights reserved.

The importance of interactions among nutrition, seasonality and socio-sexual factors in the development of hormone-free methods for controlling fertility.

PubMed

Scaramuzzi, R J; Martin, G B

2008-07-01

Around the world, consumers are demanding animal products that are produced to agreed standards for human health, environmental management and animal welfare. This has led to the development in Australia of the concept of 'clean, green and ethical' (CGE) animal production based on the manipulation of nutrition ('focus feeding') and the application of phenomena, such as the 'male effect', to provide 'natural' methods for managing small ruminant production systems. With respect to the management of fertility, CGE involves utilization of the inherited responses of animals to environmental factors to manipulate their reproductive processes. The successful development and implementation of this new generation of management tools depends on a thorough yet holistic understanding of the interactions among environmental factors and the ways these interactions affect reproductive physiology and behaviour of the animal. For sheep and goats, a central aspect of CGE management is the way in which ovarian function is affected by three major factors (nutrition, photoperiod and socio-sexual signals) and by interactions among them. Nutrition can exert two profound yet contrasting types of effect on ovarian activity: (i) the complete inhibition of reproduction by undernutrition through the hypothalamic mechanism that controls ovulation and (ii) the enhancement of fecundity by nutritional supplementation, through a direct ovarian mechanism, in females that are already ovulating. A similarly profound control over ovarian function in female sheep and goats is exerted by the well-known endocrine responses to photoperiod (seasonality) and to male socio-sexual signals. The 'male effect' already has a long history as a valuable technique for inducing a synchronized fertile ovulation during seasonal and post-partum anoestrus in sheep and goats. Importantly, experimentation has shown that these three major environmental factors interact, synergistically and antagonistically, but the precise nature of these interactions and their significance to reproductive outcomes are not well understood. Most research to date has been with small ruminants but CGE principles can be applied to any species in a managed environment. For example, a male effect has been reported for lactating cattle and, in the horse, the pattern of seasonality of oestrus can be altered by nutrition. Well-fed mares have a longer breeding season and some animals become non-seasonal. Similar observations have been reported for sheep and goats. By working towards a holistic perspective of the physiology, nutrition, genetics and behaviour of our animals, we will be able to formulate ways to manipulate the animals' environment that will improve management, productivity and profitability and, simultaneously, promote a CGE industry.

Pre- and post-partum mild underfeeding influences gene expression in the reproductive tract of cyclic dairy cows.

PubMed

Valour, D; Hue, I; Degrelle, S A; Déjean, S; Marot, G; Dubois, O; Germain, G; Humblot, P; Ponter, A A; Charpigny, G; Grimard, B

2013-06-01

Undernutrition before and after calving has a detrimental effect on the fertility of dairy cows. The effect of nutritional stress was previously reported to influence gene expression in key tissues for metabolic health and reproduction such as the liver and the genital tract early after calving, but not at breeding, that is, between 70 and 90 days post-partum. This study investigated the effects of pre- and post-partum mild underfeeding on global gene expression in the oviduct, endometrium and corpus luteum of eight multiparous Holstein cows during the early and middle phases of an induced cycle 80 days post-partum. Four control cows received 100% of energy and protein requirements during the dry period and after calving, while four underfed received 80% of control diet. Oestrous synchronization treatment was used to induce ovulation on D80 post-partum. Oviducts, ovaries and the anterior part of each uterine horn were recovered surgically 4, 8, 12 and 15 days after ovulation. Corpora lutea were dissected from the ovaries, and the endometrium was separated from the stroma and myometrium in each uterine horn. The oviduct segments were comprised of ampulla and isthmus. RNAs from ipsi- and contralateral samples were pooled on an equal weight basis. In each tissue, gene expression was assessed on a custom bovine 10K array. No differentially expressed gene (DEG) in the corpus luteum was identified between underfed and control, conversely to 293 DEGs in the oviduct vs 1 in the endometrium under a false discovery rate (FDR) < 0.10 and 1370 DEGs vs 3, respectively, under FDR < 0.15. Additionally, we used dedicated statistics (regularized canonical correlation analysis) to correlate the post-partum patterns of six plasma metabolites and hormones related to energy metabolism measured weekly between calving and D80 with gene expression. High correlations were observed between post-partum patterns of IGF-1, insulin, β-hydroxybutyrate and the expression in the oviduct of genes related to reproductive system disease, connective tissue disorders and metabolic disease. Moreover, we found special interest in the literature to retinoic acid-related genes (e.g. FABP5/CRABP2) that might indicate abnormalities in post-partum tissue repair mechanisms. In conclusion, this experiment highlights relationships between underfeeding and gene expression in the oviduct and endometrium after ovulation in cyclic Holstein cows. This might help to explain the effect of mild undernutrition on fertilization failure and early embryonic mortality in post-partum dairy cows. © 2012 Blackwell Verlag GmbH.

Characteristics of ovulation method acceptors: a cross-cultural assessment.

PubMed

Klaus, H; Labbok, M; Barker, D

1988-01-01

Five programs of instruction in the ovulation method (OM) in diverse geographic and cultural settings are described, and characteristics of approximately 200 consecutive OM acceptors in each program are examined. Major findings include: the religious background and family size of acceptors are variable, as is the level of previous contraceptive use. Acceptors are drawn from a wide range of socioeconomic and religious backgrounds; however, family planning intention was similarly distributed in all five countries. In sum, the ovulation method is accepted by persons from a variety of backgrounds within and between cultural setting.

[Comparison of the frequency of chromosomal disorders in populations of in vitro-matured and ovulating rat oocytes].

PubMed

Kitaev, E M; Pimenova, M N

1980-12-01

The rat oocytes extracted from the rat ovaries and cultivated for 42-46 hours were compared with ovulated oocytes by the chromosomal aberration rate. The chromosomal aberration rate in the population of "follicular" oocytes was 8.2% on the average whereas in ovulated oocytes, it did not exceed 1.8%. Analysis of the chromosomal aberrations depending on the phase of the estral cycle suggests that the main portion of chromosomal aberrations in cultivated oocytes occurs during the physiological process of follicular atresia.

On the designing of a tamper resistant prescription RFID access control system.

PubMed

Safkhani, Masoumeh; Bagheri, Nasour; Naderi, Majid

2012-12-01

Recently, Chen et al. have proposed a novel tamper resistant prescription RFID access control system, published in the Journal of Medical Systems. In this paper we consider the security of the proposed protocol and identify some existing weaknesses. The main attack is a reader impersonation attack which allows an active adversary to impersonate a legitimate doctor, e.g. the patient's doctor, to access the patient's tag and change the patient prescription. The presented attack is quite efficient. To impersonate a doctor, the adversary should eavesdrop one session between the doctor and the patient's tag and then she can impersonate the doctor with the success probability of '1'. In addition, we present efficient reader-tag to back-end database impersonation, de-synchronization and traceability attacks against the protocol. Finally, we propose an improved version of protocol which is more efficient compared to the original protocol while provides the desired security against the presented attacks.

The Use of a Dexamethasone-inducible System to Synchronize Xa21 Expression to Study Rice Immunity.

PubMed

Caddell, Daniel F; Wei, Tong; Park, Chang-Jin; Ronald, Pamela C

2015-05-05

Inducible gene expression systems offer researchers the opportunity to synchronize target gene expression at particular developmental stages and in particular tissues. The glucocorticoid receptor (GR), a vertebrate steroid receptor, has been well adopted for this purpose in plants. To generate steroid-inducible plants, a construct of GAL4-binding domain-VP16 activation domain-GR fusion (GVG) with the target gene under the control of upstream activation sequence (UAS) has been developed and extensively used in plant research. Immune receptors perceive conserved molecular patterns secreted by pathogens and initiate robust immune responses. The rice immune receptor, XA21 , recognizes a molecular pattern highly conserved in all sequenced genomes of Xanthomonas , and confers robust resistance to X. oryzae pv. oryzae ( Xoo ). However, identifying genes downstream of XA21 has been hindered because of the restrained lesion and thus limited defense response region in the plants expressing Xa21 . Inducible expression allows for a synchronized immune response across a large amount of rice tissue, well suited for studying XA21-mediated immunity by genome-wide approaches such as transcriptomics and proteomics. In this protocol, we describe the use of this GVG system to synchronize Xa21 expression.