Artykuły w czasopismach na temat „Transfert asynchrone”
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Ho, Hao Tam, Hao Tam Ho, Emily Orchard-Mills, Hao Tam Ho, Emily Orchard-Mills i David Alais. "Visuotactile Temporal Recalibration Transfers Across Different Locations". Multisensory Research 28, nr 3-4 (2015): 351–70. http://dx.doi.org/10.1163/22134808-00002498.
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Following prolonged exposure to audiovisual asynchrony, an observer’s point of subjective simultaneity (PSS) shifts in the direction of the leading modality. It has been debated whether other sensory pairings, such as vision and touch, lead to a similar temporal recalibration, and if so, whether the internal timing mechanism underlying lag visuotactile adaptation is centralised or distributed. To address these questions, we adapted observers to vision- and tactile-leading visuotactile asynchrony on either their left or right hand side in different blocks. In one test condition, participants performed a simultaneity judgment on the adapted side (unilateral) and in another they performed a simultaneity judgment on the non-adapted side (contralateral). In a third condition, participants adapted concurrently to equal and opposite asynchronies on each side and were tested randomly on either hand (bilateral opposed). Results from the first two conditions show that observers recalibrate to visuotactile asynchronies, and that the recalibration transfers to the non-adapted side. These findings suggest a centralised recalibration mechanism not linked to the adapted side and predict no recalibration for the bilateral opposed condition, assuming the adapted effects were equal on each side. This was confirmed in the group of participants that adapted to vision- and tactile-leading asynchrony on the right and left hand side, respectively. However, the other group (vision-leading on the left and tactile-leading on the right) did show a recalibration effect, suggesting a distributed mechanism. We discuss these findings in terms of a hybrid model that assumes the co-existence of a centralised and distributed timing mechanism.
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Wilsher, Sandra, Amber Clutton-Brock i W. R. Allen. "Successful transfer of day 10 horse embryos: influence of donor–recipient asynchrony on embryo development". REPRODUCTION 139, nr 3 (marzec 2010): 575–85. http://dx.doi.org/10.1530/rep-09-0306.
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A total of 78 day 10 horse embryos were transferred non-surgically to recipient mares that had ovulated 9, 7, 6, 5, 4, 3, 2 or 1 day after (negative asynchrony), on the same day (synchronous), or 2 or 4 days before (positive asynchrony) the donor (n=6 or 8 mares per group). Pregnancy rates between 100% (6/6) and 63% (5/8) were seen in recipient mares that were between +2 and −6 days asynchronous. Embryo survival to the heartbeat stage declined in recipients that were −7 days asynchronous and no embryos survived in recipients that were −9 days asynchronous. Irrespective of uterine asynchrony, cessation of embryo mobility and fixation at the base of a uterine horn occurred when the conceptus was ∼17 days old. Conceptus growth and development was slowed when embryos were placed in negatively asynchronous uteri. At the greatest degree of negative asynchrony at which embryos survived to the heartbeat stage, i.e. −7 and −6 days, development of the embryo proper and allantois was retarded. Luteostasis was achieved in recipient mares when day 10 embryos were transferred to recipient mares at any stage of asynchrony between −9 and +2 days with respect to the donor. These results indicate that in the horse, there is a wide window for establishment of pregnancy following embryo transfer to asynchronous recipients. Although progesterone priming of the uterus to a stage equivalent to that of the transferred embryo does not appear to be a prerequisite for embryo survival, it does nonetheless influence embryonic development.
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Rodríguez-Alonso, Beatriz, José María Sánchez, Meriem Hamdi, Michael McDonald, Vitezslav Havlicek, Urban Besenfelder, Patrick Lonergan i Dimitrios Rizos. "Asynchrony between the early embryo and the reproductive tract affects subsequent embryo development in cattle". Reproduction, Fertility and Development 32, nr 6 (2020): 564. http://dx.doi.org/10.1071/rd19360.
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The aim of this study was to determine the effect of maternal–embryonic asynchrony in the reproductive tract (oviduct and uterus) on subsequent embryo development in cattle. Fifty Day 1invitro-produced zygotes were transferred endoscopically into the oviduct ipsilateral to the corpus luteum of heifers (n=40) that were either synchronous with the embryos (Day 1 after ovulation) or asynchronous and ahead of the embryo (Day 3 after ovulation). A subset of heifers was killed in a commercial abattoir 3, 6 or 14 days after embryo transfer. Location within the reproductive tract, developmental stage and the quality of embryos were recorded. Transfer of embryos to an advanced (asynchronous) oviduct resulted, on Day 4, in fewer embryos at the expected location (oviduct), and a greater number of degenerated and retarded embryos with a lower total cell number than for embryos in the synchronous group. Similarly, on Day 7, asynchrony led to a greater number of degenerated and retarded embryos compared with the synchronous group. Total embryo cell number was similar among groups. Although Day 15 conceptuses were longer following asynchronous transfer, only 50% of the asynchronous heifers yielded conceptuses, compared with 100% in the synchronous group. In conclusion, asynchrony between the developing embryo and the reproductive tract has a negative effect on embryo development.
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Tiegs, A. W., L. Sun, G. Patounakis i R. T. Scott. "Worth the wait? Day 7 blastocysts have lower euploidy rates but similar sustained implantation rates as Day 5 and Day 6 blastocysts". Human Reproduction 34, nr 9 (12.08.2019): 1632–39. http://dx.doi.org/10.1093/humrep/dez138.
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Abstract STUDY QUESTION Does the reproductive potential of embryos change when blastocyst development takes longer than the traditionally accepted 5 days when accounting for aneuploidy and endometrial-embryo asynchrony? SUMMARY ANSWER Aneuploidy increases with increasing duration of blastulation, but if blastocyst morphologic quality and endometrial-embryo asynchrony are controlled for, euploid Day 7 embryos have similar sustained implantation as compared to Days 5 and 6 euploid blastocysts. WHAT IS KNOWN ALREADY The relative contributions of diminished embryo quality versus endometrial and embryo asynchrony to poor outcomes associated with embryos cultured past Day 6 are not clear. Asynchrony can be eliminated by embryo vitrification with transfer in a subsequent month after retrieval. STUDY DESIGN, SIZE, DURATION Retrospective cohort study of patients from a single center attempting conception through ICSI and utilizing preimplantation genetic testing for aneuploidy screening (PGT-A) from January 2017 to September 2018. Cycles were excluded if they utilized surgical sperm or preimplantation genetic testing for monogenetic/single gene defects. ICSI cycle outcomes from 2586 patients were evaluated for ploidy status of embryos. PARTICIPANTS/MATERIALS, SETTING, METHODS Only patients undergoing single, euploid frozen embryo transfer were included when analyzing cycle outcomes by day of blastocyst expansion of the transferred embryo (n = 2130). Ploidy rates by the day upon which an embryo was considered to be usable (denoted, ‘usable blastulation day’) were determined so as to assess the contribution of aneuploidy to slow embryo development. Outcomes of euploid frozen single embryo transfers (SET) of Day 7 embryos were evaluated to assess the reproductive potential associated with embryos that were slowly developing for reasons other than aneuploidy. Analyses were adjusted by maternal age and blastocyst morphology. MAIN RESULTS AND THE ROLE OF CHANCE Overall, 67.7% (n = 3508) of usable Day 5 blastocysts were euploid, 52.1% (n = 5560) of usable Day 6 blastocysts were euploid and 43.1% (n = 229) of usable Day 7 embryos were euploid (Day 5 versus Day 6: odds ratio (OR) 0.7 (95% CI, 0.64–0.76), P < 0.001; Day 5 versus Day 7: OR 0.56 (95% CI, 0.46–0.69), P < 0.001; Day 6 versus Day 7: OR 0.81 (95% CI, 0.67–0.99), P = 0.036). Stratified by Society for Assisted Reproductive Technology maternal age groups, a reduction in the prevalence of euploidy by increasing time to embryo blastulation was still seen. The sustained implantation rate (SIR) was similar after euploid SET of Days 5 and 6 embryos (overall, 68.9% (95% CI, 66.0–71.6) and 66.8% (95% CI, 63.8–69.7), respectively; P = 0.81). SIR after euploid Day 7 SET appeared slightly lower than that of Days 5 and 6 embryos (52.6% (95% CI, 35.8–69.0); (Day 5 versus Day 7: OR, 0.67 (95% CI, 0.32–1.41), P = 0.29; Day 6 versus Day 7: OR 0.58 (95% CI, 0.28–1.2), P = 0.14)) but did not achieve statistical significance. LIMITATIONS, REASONS FOR CAUTION The primary limitation is the low number of Day 7 blastocyst transfers that limits statistical power. Additionally, the retrospective nature of this study may prevent full elucidation of potential biases with respect to culture, morphologic assessment and selection of Day 7 embryos for transfer. WIDER IMPLICATIONS OF THE FINDINGS Routine culture through Day 7 may successfully increase the pool of transferrable embryos for patients who would otherwise have no usable embryos if culture terminated on Day 6. This is particularly true for older patients (i.e. greater than 35 years of age), whose embryos take longer to blastulate and, therefore, are more susceptible to cycle cancelation. Additionally, as evidenced by an adequate overall SIR of 52.6% after euploid SET of Day 7 blastocysts, embryos developing to a usable blastocyst on Day 7 are likely within the ‘window of blastulation.’ STUDY FUNDING/COMPETING INTEREST(S) None.
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WILSHER, S., M. KÖLLING i W. R. ALLEN. "Meclofenamic acid extends donor-recipient asynchrony in equine embryo transfer". Equine Veterinary Journal 38, nr 5 (5.01.2010): 428–32. http://dx.doi.org/10.2746/042516406778400547.
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García, María-Luz, Rafik Belabbas, Raquel Muelas, Iván Agea i María-José Argente. "Asynchrony between in vivo and in vitro rabbit embryos". Revista Colombiana de Ciencias Pecuarias 35, nr 2 (5.04.2022): 118–23. http://dx.doi.org/10.17533/udea.rccp.v35n2a02.
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Background: Comparative features of embryos developed under in vitro and in vivo conditions are particularly important in designing embryo transfer procedures that fulfil embryo-recipient synchronization requirements. Objective: To determine the degree of asynchrony in rabbit embryo development between cultured and in vivo embryos. Methods: A total of 55 non-lactating multiparous female rabbits were used. Embryos were classified as 16-cells or early morulae at 48 hours post-coitum (hpc). Embryos were cultured during 30 or 32 h and embryo development was compared with in vivo embryos of 72 hpc. In vitro and in vivo embryos at 72 hpc were classified as early or compacted morulae. Bayesian statistics was used. Difference between in vivo and in vitro embryos and the actual probability of the difference between the in vivo and in vitro embryo higher than zero (P) was estimated. Results: The percentage of compacted morulae was higher in in vivo embryos than in in vitro embryos with +6 h of asynchrony (73.5 and 32.8%, P=1.00). But the percentage of compacted morulae was similar with +8 h asynchrony. Conclusions: In vitro embryos delay their development by + 8 hours compared to in vivo embryos.
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Pan, Qing, Mengzhe Jia, Qijie Liu, Lingwei Zhang, Jie Pan, Fei Lu, Zhongheng Zhang, Luping Fang i Huiqing Ge. "Identifying Patient–Ventilator Asynchrony on a Small Dataset Using Image-Based Transfer Learning". Sensors 21, nr 12 (17.06.2021): 4149. http://dx.doi.org/10.3390/s21124149.
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Mechanical ventilation is an essential life-support treatment for patients who cannot breathe independently. Patient–ventilator asynchrony (PVA) occurs when ventilatory support does not match the needs of the patient and is associated with a series of adverse clinical outcomes. Deep learning methods have shown a strong discriminative ability for PVA detection, but they require a large number of annotated data for model training, which hampers their application to this task. We developed a transfer learning architecture based on pretrained convolutional neural networks (CNN) and used it for PVA recognition based on small datasets. The one-dimensional signal was converted to a two-dimensional image, and features were extracted by the CNN using pretrained weights for classification. A partial dropping cross-validation technique was developed to evaluate model performance on small datasets. When using large datasets, the performance of the proposed method was similar to that of non-transfer learning methods. However, when the amount of data was reduced to 1%, the accuracy of transfer learning was approximately 90%, whereas the accuracy of the non-transfer learning was less than 80%. The findings suggest that the proposed transfer learning method can obtain satisfactory accuracies for PVA detection when using small datasets. Such a method can promote the application of deep learning to detect more types of PVA under various ventilation modes.
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Bird, Tania L. F., Pua Bar (Kutiel), Elli Groner i Amos Bouskila. "Asynchrony Drives Plant and Animal Community Stability in Mediterranean Coastal Dunes". Applied Sciences 11, nr 13 (5.07.2021): 6214. http://dx.doi.org/10.3390/app11136214.
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Substantial evidence now suggests that a positive diversity–stability relationship exists. Yet few studies examine the facets of biodiversity that contribute to this relationship, and empirical research is predominantly conducted on grassland communities under controlled conditions. We investigate the roles of species richness, environmental condition (vegetation cover), asynchrony, and weighted population stability in driving community stability across multiple taxa. We used data from a Long-term Ecological Research project to investigate temporal stability of annual plants, beetles, reptiles, and rodents in Nizzanim Coastal Sand Dune Nature Reserve in Israel. All four taxa had a strong positive relationship between asynchrony and community stability. Only rodents showed a positive richness–stability relationship. Perennial plant cover had a significant relationship with community stability for three taxa, but the direction of the correlation varied. Asynchrony had a stronger relationship with perennial plant cover than it did with richness for both plants and beetles. We suggest that community stability is driven by asynchrony for flora as well as fauna. Stability appears to be determined by species’ interactions and their responses to the environment, and not always by diversity. This has important consequences for understanding the effects of environmental degradation on ecosystem stability and productivity, which have destabilizing consequences beyond biodiversity loss.
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Melican, D., R. Butler, N. Hawkins, S. Nims, N. Buzzel, T. Jellerette i W. Gavin. "58ESTRUS SYNCHRONIZATION OF DAIRY GOATS UTILIZED AS RECIPIENTS FOR CAPRINE NUCLEAR TRANSFER EMBRYOS". Reproduction, Fertility and Development 16, nr 2 (2004): 151. http://dx.doi.org/10.1071/rdv16n1ab58.
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The timing of estrus synchrony between donor and recipient does is an important consideration in an embryo transfer program. Experiments were conducted to determine the optimal time of estrus synchrony between donor and recipient dairy goats used in a commercial nuclear transfer (NT) program. Donor and recipient synchronization was achieved by implanting either a 3-mg norgestomet ear implant (Crestar®, Intervet Int. B.V., Boxmeer, Holland) or a 300-mg progesterone vaginal implant (CIDR-G®, Pharmacia and Upjohn Ltd. Co., Auckland, NZ) on Day 0. A single 5mg intramuscular injection of prostaglandin (Lutalyse®, Pharmacia and Upjohn, Kalamazoo, MI, USA) was administered on Day 7. Recipients received a single 200–500IU intramuscular injection of PMSG (Calbiochem, LaJolla, CA, USA) on Day 13. Alternatively, starting on Day 12 donors received twice daily intramuscular injection (64mg/day) of FSH (Folltropin®, Vetrepharm, Ontario, Canada) over four consecutive days. On Day 15 the implants were removed from both donors and recipients and the animals were mated several times daily to vasectomized bucks over two consecutive days. In Experiment 1, estrus synchrony or asynchrony was achieved by removing the implant from recipients at the same time or 12h later than donors, respectively. In Experiment 2, only estrus asynchrony was utilized and was achieved by removing the implant from recipients either 12 or 18h later than donors. In vivo-ovulated MII oocytes surgically recovered from superovulated donors on Day 17 were enucleated and reconstructed with transfected caprine fetal or adult skin cells or transgenic adult skin cells. Couplets were simultaneously fused, activated, and then cultured in SOF/BSA for 48h at 38°C. Two-to-eight-cell NT embryos at 48h post-fusion and activation were surgically transferred to the oviducts of surrogate recipients with similar implant types and PMSG doses. Pregnancies were determined by ultrasonography starting at approximately Day 28 post-fusion and activation and then monitored weekly. In Experiment 1, there were significantly more pregnant asynchronous recipients compared with synchronous recipients (6 of 24 v. 12 of 124 does, respectively). While there were no significant differences, more offspring were produced per embryo transferred to asynchronous recipients compared with synchronous recipients (5 of 135 v. 11 of 690 offspring per embryo transferred, respectively). In Experiment 2, while not significant, there were more pregnant +12-h asynchronous recipients compared with +18-h asynchronous recipients (16 of 72 v. 5 of 36 does, respectively). Again, while there were no significant differences, more offspring were produced per embryo transferred to +12h compared with +18h asynchronous recipients (11 of 424 v. 3 of 224 offspring per embryo transferred, respectively). These results suggest that asynchrony of estrus between recipients and donors is more beneficial in a commercial caprine NT program, and that +12h may be a more optimal period of asynchrony for recipient does receiving NT embryos. Table 1 Summary of recipient estrus synchronization
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Stout, T. A., C. Gibson i M. de Ruijter Villani. "112 EFFECT OF ASYNCHRONOUS EMBRYO TRANSFER ON GLUCOSE TRANSPORTER EXPRESSION IN EQUINE TROPHECTODERM". Reproduction, Fertility and Development 27, nr 1 (2015): 148. http://dx.doi.org/10.1071/rdv27n1ab112.
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Equine pregnancy is characterised by an unusually long pre-implantation period (40 days) during which the conceptus is entirely dependent on uterine secretions for nutrient provision; although glucose is an important nutrient during development post-blastocyst formation, little is known about its transport into the early horse conceptus. Equine embryos are also known to tolerate an unusually large degree of uterine asynchrony following embryo transfer (ET). However, negative asynchrony (recipient behind the donor) of more than 5 days markedly retards conceptus growth and development, and thereby offers a unique tool for studying the effect of the uterine environment on early development. In a preliminary study, we detected abundant mRNA expression for the facilitative glucose transporters (SLC2As) 1–3, 5, 8 and 10 and sodium-glucose co-transporter (SLC5A)11 in Day 14 to 28 equine conceptus membranes. In the current study, we evaluated the effect of uterine asynchrony on trophectodermal glucose transporter expression. Day 8 horse embryos were transferred to recipient mares that ovulated on the same day (synchronous; n = 10) or 5 days after (asynchronous; n = 10) the donor mare. The conceptuses were collected 6 or 11 days after ET (Day 14 or 19 of embryo development: n = 5 per group). Trophectodermal mRNA expression for glucose transporters was evaluated by RT-qPCR, and the effects of asynchronous ET and stage of pregnancy were analysed by two-way ANOVA followed by independent-samples t-tests. Gene expression for SLC2A3 and 8 was stable over time and treatment. Expression of SLC2A1 and SLC5A11 decreased between Days 14 and 19 in synchronous pregnancies only (P < 0.05). SLC2A2 expression increased markedly on Day 19 in synchronous (P < 0.01) but not asynchronous pregnancies (P < 0.05). SLC2A5 expression was lower in the asynchronous group on Day 14, but increased beyond expression levels in synchronous pregnancies by Day 19 (P < 0.05). In summary, expression of SLC2A1 and 3, the major placental glucose transporters, was not affected by asynchronous ET. The marked up-regulation of SLC2A2 expression between Days 14 and 19 of synchronous but not asynchronous pregnancy suggests a stage-specific function, whereas the increase in SLC2A5 at Day 19 after asynchronous ET could be a compensatory response to growth retardation. This study was funded by EpiHealthNet (Project number 317146).
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Wieczorkiewicz, Maria, Jędrzej M. Jaśkowski, Agnieszka Wichtowska, Monika Olszewska-Tomczyk i Bartłomiej M. Jaśkowski. "Effectiveness of embryo transfer in cows - risk factors including in vivo derived and in vitro produced embryos". Medical Journal of Cell Biology 9, nr 3 (1.09.2021): 123–31. http://dx.doi.org/10.2478/acb-2021-0017.
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Abstract Multiple Ovulation Embryo Transfer is a biotech method with more than 50 years of history and an established position in cattle breeding. This procedure is beneficial in many ways, but it also carries a risk of failure. The study presents the overview of the most important risk factors that may affect conception rates in the course of embryo transfer, including the factors associated with the embryo sourcing (embryo production method, embryo quality, development stage and breed, embryo storage method), embryo transfer procedure (synchrony/asynchrony, embryo transfer difficulty, the time of the transcervical insemination gun passage, depth of embryo deposition, localization and structure of the corpus luteum relative to the follicle and both individual characteristics of donors and recipients (level of concentration of progesterone, the state of health of the udder, lactation level, body condition score and age) and some environmental factors.
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Gibson, Charlotte, Marta de Ruijter-Villani, Stefan Bauersachs i Tom A. E. Stout. "Asynchronous Embryo Transfer Followed by Comparative Transcriptomic Analysis of Conceptus Membranes and Endometrium Identifies Processes Important to the Establishment of Equine Pregnancy". International Journal of Molecular Sciences 21, nr 7 (7.04.2020): 2562. http://dx.doi.org/10.3390/ijms21072562.
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Preimplantation horse conceptuses require nutrients and signals from histotroph, the composition of which is regulated by luteal progesterone and conceptus-secreted factors. To distinguish progesterone and conceptus effects we shortened the period of endometrial progesterone-priming by asynchronous embryo transfer. Day 8 embryos were transferred to synchronous (day 8) or asynchronous (day 3) recipients, and RNA sequencing was performed on endometrium and conceptuses recovered 6 and 11 days later (embryo days 14 and 19). Asynchrony resulted in many more differentially expressed genes (DEGs) in conceptus membranes (3473) than endometrium (715). Gene ontology analysis identified upregulation in biological processes related to organogenesis and preventing apoptosis in synchronous conceptuses on day 14, and in cell adhesion and migration on day 19. Asynchrony also resulted in large numbers of DEGs related to ‘extracellular exosome’. In endometrium, genes involved in immunity, the inflammatory response, and apoptosis regulation were upregulated during synchronous pregnancy and, again, many genes related to extracellular exosome were differentially expressed. Interestingly, only 14 genes were differentially expressed in endometrium recovered 6 days after synchronous versus 11 days after asynchronous transfer (day 14 recipient in both). Among these, KNG1 and IGFBP3 were consistently upregulated in synchronous endometrium. Furthermore bradykinin, an active peptide cleaved from KNG1, stimulated prostaglandin release by cultured trophectoderm cells. The horse conceptus thus responds to a negatively asynchronous uterus by extensively adjusting its transcriptome, whereas the endometrial transcriptome is modified only subtly by a more advanced conceptus.
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Verbanck, Sylvia, Daniel Schuermans, Sophie Van Malderen, Walter Vincken i Bruce Thompson. "The effect of conductive ventilation heterogeneity on diffusing capacity measurement". Journal of Applied Physiology 104, nr 4 (kwiecień 2008): 1094–100. http://dx.doi.org/10.1152/japplphysiol.00917.2007.
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It has long been assumed that the ventilation heterogeneity associated with lung disease could, in itself, affect the measurement of carbon monoxide transfer factor. The aim of this study was to investigate the potential estimation errors of carbon monoxide diffusing capacity (DlCO) measurement that are specifically due to conductive ventilation heterogeneity, i.e., due to a combination of ventilation heterogeneity and flow asynchrony between lung units larger than acini. We induced conductive airway ventilation heterogeneity in 35 never-smoker normal subjects by histamine provocation and related the resulting changes in conductive ventilation heterogeneity (derived from the multiple-breath washout test) to corresponding changes in diffusing capacity, alveolar volume, and inspired vital capacity (derived from the single-breath DlCO method). Average conductive ventilation heterogeneity doubled ( P < 0.001), whereas DlCO decreased by 6% ( P < 0.001), with no correlation between individual data ( P > 0.1). Average inspired vital capacity and alveolar volume both decreased significantly by, respectively, 6 and 3%, and the individual changes in alveolar volume and in conductive ventilation heterogeneity were correlated ( r = −0.46; P = 0.006). These findings can be brought in agreement with recent modeling work, where specific ventilation heterogeneity resulting from different distributions of either inspired volume or end-expiratory lung volume have been shown to affect DlCO estimation errors in opposite ways. Even in the presence of flow asynchrony, these errors appear to largely cancel out in our experimental situation of histamine-induced conductive ventilation heterogeneity. Finally, we also predicted which alternative combination of specific ventilation heterogeneity and flow asynchrony could affect DlCO estimate in a more substantial fashion in diseased lungs, irrespective of any diffusion-dependent effects.
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KIEU, Violet, Alex POLYAKOV, Genia ROZEN, Daniel LANTSBERG, Kate STERN i Wan Tinn TEH. "A Cross-Sectional Analysis of Live Birth Rates in Day 5 Fresh Versus Vitrified Single Blastocyst Transfer Cycles". Fertility & Reproduction 04, nr 03n04 (wrzesień 2022): 138. http://dx.doi.org/10.1142/s2661318222740504.
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Background: The use of frozen embryo transfers (FETs) in assisted reproduction has increased worldwide. Proponents of FETs suggest that controlled ovarian hyperstimulation (COH) in a fresh transfer impairs endometrial-embryo synchronicity, however there has been conflicting evidence on live birth rate (LBR) and clinical pregnancy rate (CPR) outcomes. Aim: To compare LBRs and CPRs between single autologous day 5 fresh versus vitrified blastocyst transfer cycles, in order to investigate the impact of COH on embryo-endometrium asynchrony. Method: A large cross-sectional analysis of 6,002 embryo transfers (ETs), comprising of 3774 fresh and 2228 FET cycles from 2016-2019. Inclusion criteria: first two stimulation cycles, single ET, and no pre-implantation genetic testing for aneuploidy (PGT-A). Multivariate analysis performed, also sub-group analysis for high-responders (>20 oocytes collected). Results: Univariate analysis showed no absolute difference in LBR (28.3% vs 27.4%, p=0.43) and CPR (32.2% vs 30.9%, p=0.30), however multivariate analysis demonstrated significantly lower LBR (OR 0.864, p<0.05, 95% CI 0.749-0.997) and CPR (OR 0.852, p<0.05, 95% CI 0.742-0.979) in FET compared to fresh ETs. Younger patient age, previous IVF pregnancy, advanced blastocyst expansion, higher trophectoderm quality and lower cumulative number of ETs all improved the odds of both LBR and CPR (p<0.001). Conventional IVF, rather than ICSI, improved CPR (p<0.05) but not LBR (p=0.138). BMI affected neither LBR (p=0.492) nor CPR (p=0.359). In sub-group multivariate analysis of high-responders, no significant difference in LBR (p=0.439) or CPR (p=0.450) noted. Conclusion: This study demonstrates a relative higher LBR and CPR for fresh ETs compared to FETs, in multivariate analysis. Having a FET decreased the odds of LBR by nearly 14% compared to fresh ET, when adjusted for confounders. Our results suggest that universal freeze-all strategy, without appropriate indication, may lead to suboptimal outcomes. In high-responders, freeze-all cycles may be beneficial, as adjusted outcomes appear to be similar.
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Gao, Pin, Yihao Huang, Feng He i Hongzhi Qi. "Improve P300-speller performance by online tuning stimulus onset asynchrony (SOA)". Journal of Neural Engineering 18, nr 5 (1.10.2021): 056067. http://dx.doi.org/10.1088/1741-2552/ac2f04.
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Abstract Objective. The P300-Speller is a classic brain–computer interface paradigm that has been subjected to numerous clinical trials. Some studies have reported that the performance of the P300-Speller is closely related to stimulus onset asynchrony (SOA), but very few studies have attempted to improve the performance of the P300-Speller by optimizing SOA. Approach. In this paper, we designed a P300-Speller system based on a variable SOA and dynamic stop strategy, which can automatically adjust SOA according to real-time operational performance. Main results. The online experiment results of 18 subjects showed that the event-related potential classifier and the dynamic stop algorithm established at 200 ms SOA can maintain the performance at a certain level among 50–300 ms SOA. The system can then reduce the SOA from an initial 200 ms to an average of about 98.5 ms while maintaining letter output accuracy. The average theoretical information transfer rate was significantly improved from 42.4 to 85 bit min−1 (the maximum was 232 bit min−1). Significance. These results demonstrate that the system established in this paper can automatically optimize the SOA settings, and this personalized SOA adjustment can effectively improve the performance of the P300-Speller.
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Li, Qingfu, Hao Guo i Biao Guo. "The Dual-Parameter Control of Synchronization in Steel Box Girder Incremental Launching Construction". Applied Sciences 13, nr 21 (6.11.2023): 12074. http://dx.doi.org/10.3390/app132112074.
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When a steel box girder is constructed using the jacking method, the contact area between the jack and the bottom of the girder is subjected to complex forces, and it is very critical to ensure the local stability of the girder. When the phenomenon of unsynchronized jacking occurs, it will lead to changes in the contact area and affect the structural safety. In order to solve the above problems, this paper takes the background of the incremental launching construction of the main bridge across the Yellow River on Jiao Ping Expressway, adopts the Midas FEA NX 2021 finite element software to establish a finite element hybrid unit model under the maximum cantilever condition for the first time, and analyzes the local stresses in this state. The results show that the local maximum equivalent stress of the steel box girder is 198.301 MPa, which meets the requirements. The effect of jacking asynchrony on the structural forces is analyzed by simulating jacking asynchrony in the local model. The results show that both vertical jacking asynchrony and lateral deflection will lead to an increase in local stresses in the steel box girder and even steel yielding. On the basis of the above single-parameter study, a two-parameter correlation analysis is carried out to obtain the two-parameter control equation of jacking, the control threshold of the vertical jacking height difference is formulated to be 15 mm, and the dynamic control of lateral deflection is realized according to the control equation. Through comparison, it is found that the two-parameter control threshold of jacking synchronization is reduced, which can supplement the unfavorable state missed during single-parameter control and is a safer and more effective means of control.
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Gibson, C., M. de Ruijter Villani i T. A. Stout. "114 ASYNCHRONOUS EMBRYO TRANSFER AFFECTS THE EXPRESSION OF IMPRINTED GENES IN EQUINE TROPHECTODERM". Reproduction, Fertility and Development 27, nr 1 (2015): 149. http://dx.doi.org/10.1071/rdv27n1ab114.
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Gene imprinting is a form of epigenetic modification that results in parent-of-origin specific monoallelic expression. Imprinted genes play important roles during fetal-placental growth with paternally imprinted genes generally promoting and maternally imprinted genes suppressing fetal growth. Imprinted genes are therefore believed to have important effects on trophoblast differentiation and placental development, and in adjusting fetal nutrition to maternal supply. The horse is an interesting model of early placental development because of its unusually long pre-implantation period (40 days), during which the conceptus is dependent on uterine secretions for nutrient provision. Moreover, horse embryos tolerate a wide range of uterine asynchrony following embryo transfer (ET), offering a unique tool to study maternal influences on conceptus development. This study examined the effect of asynchronous ET on the expression of imprinted genes in equine trophectoderm. Twenty Day 8 embryos were transferred to recipient mares that either ovulated on the same day (synchronous; n = 10) or 5 days after (asynchronous; n = 10) the donor mare. The conceptuses were recovered 6 or 11 days after ET (Day 14 or 19 of conceptus development; n = 5 per group). Bilaminar trophectoderm was isolated and mRNA expression for a range of genes known to be imprinted in equine trophectoderm (H19, PHLDA2, IGF2R, IGF2, PEG3, PEG10, SNRPN, INSR, and INS) was investigated by RT-qPCR. The effects of asynchronous ET and stage of pregnancy on gene expression were analysed by two-way ANOVA followed by independent-samples t-tests. IGF2, PEG3, PEG10, INSR, H19, and PHLDA2 all showed a significant up-regulation in gene expression between Days 14 and 19 of pregnancy; however, expression was higher in synchronous than asynchronous pregnancies at Day 19 (P < 0.05). IGF2R expression increased significantly from Day 14 to 19 in the synchronous pregnancies (P < 0.05), but did not differ between treatments at Day 19. SNRPN expression increased from Day 14 to 19, and was unaffected by asynchrony. INS mRNA was not detectable in trophectoderm. In conclusion, asynchronous ET had a significant effect on gene expression at Day 19 of gestation that was not evident at Day 14. This may be either a contributor to the delayed development that is observed in asynchronous pregnancies or a result/response; in either case, it may affect subsequent development. This study was founded by EpiHealthNet (Project number 317146).
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Hofemeier, Philipp, Rami Fishler i Josué Sznitman. "The role of respiratory flow asynchrony on convective mixing in the pulmonary acinus". Fluid Dynamics Research 46, nr 4 (9.04.2014): 041407. http://dx.doi.org/10.1088/0169-5983/46/4/041407.
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Glushneva, Iuliia. "Translation (Dis)Junctions, or Postsocialist Connectivity". A Peer-Reviewed Journal About 9, nr 1 (4.08.2020): 94–107. http://dx.doi.org/10.7146/aprja.v9i1.121492.
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This article focuses on language transfer as a fundamental factor in the construction of postsocialist network technosociality. By looking at the early days of the Internet in Russia and the current landscape of the Russian-language cyberspace, it demonstrates that excessive translation activity becomes an essential tool of postsocialist integration with global network economies and cultures. At the center of this activity is voice-over, a form of “half dubbing” and a dominant screen translation practice on the Runet. While this article explores the histories and defining features of performance and labor of this practice, it argues that the voice-over translation is a mode of connectivity that exposes the centrality of asynchrony and distortion to postsocialist networking as well as to the network as such.
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Jacob, J. C. F., K. T. Haag, G. O. Santos, J. P. Oliveira, M. O. Gastal i E. L. Gastal. "Effect of embryo age and recipient asynchrony on pregnancy rates in a commercial equine embryo transfer program". Theriogenology 77, nr 6 (kwiecień 2012): 1159–66. http://dx.doi.org/10.1016/j.theriogenology.2011.10.022.
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Ashworth, Cheryl J., i Fuller W. Bazer. "Changes in Ovine Conceptus and Endometrial Function Following Asynchronus Embryo Transfer or Administration of Progesterone1". Biology of Reproduction 40, nr 2 (1.02.1989): 425–33. http://dx.doi.org/10.1095/biolreprod40.2.425.
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Pasteka, Richard, Joao Pedro Santos da Costa, Nelson Barros, Radim Kolar i Mathias Forjan. "Patient–Ventilator Interaction Testing Using the Electromechanical Lung Simulator xPULM™ during V/A-C and PSV Ventilation Mode". Applied Sciences 11, nr 9 (21.04.2021): 3745. http://dx.doi.org/10.3390/app11093745.
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During mechanical ventilation, a disparity between flow, pressure and volume demands of the patient and the assistance delivered by the mechanical ventilator often occurs. This paper introduces an alternative approach of simulating and evaluating patient–ventilator interactions with high fidelity using the electromechanical lung simulator xPULM™. The xPULM™ approximates respiratory activities of a patient during alternating phases of spontaneous breathing and apnea intervals while connected to a mechanical ventilator. Focusing on different triggering events, volume assist-control (V/A-C) and pressure support ventilation (PSV) modes were chosen to test patient–ventilator interactions. In V/A-C mode, a double-triggering was detected every third breathing cycle, leading to an asynchrony index of 16.67%, which is classified as severe. This asynchrony causes a significant increase of peak inspiratory pressure (7.96 ± 6.38 vs. 11.09 ± 0.49 cmH2O, p < 0.01)) and peak expiratory flow (−25.57 ± 8.93 vs. 32.90 ± 0.54 L/min, p < 0.01) when compared to synchronous phases of the breathing simulation. Additionally, events of premature cycling were observed during PSV mode. In this mode, the peak delivered volume during simulated spontaneous breathing phases increased significantly (917.09 ± 45.74 vs. 468.40 ± 31.79 mL, p < 0.01) compared to apnea phases. Various dynamic clinical situations can be approximated using this approach and thereby could help to identify undesired patient–ventilation interactions in the future. Rapidly manufactured ventilator systems could also be tested using this approach.
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Duque Rodriguez, Matteo, Andrés Gambini, Laura D. Ratner, Adrian J. Sestelo, Olinda Briski, Cynthia Gutnisky, Susana B. Rulli, Rafael Fernández Martin, Pablo Cetica i Daniel F. Salamone. "Aggregation of Leopardus geoffroyi hybrid embryos with domestic cat tetraploid blastomeres". Reproduction 161, nr 5 (maj 2021): 539–48. http://dx.doi.org/10.1530/rep-20-0589.
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Heterospecific embryo transfer of an endangered species has been carried out using recipients from related domestic females. Aggregation of an embryo from an endangered species with a tetraploid embryo from the species to be transferred could improve the development of pregnancy to term. The main objective of the present study was to analyze embryo aggregation in domestic cat model using hybrid embryos. For this purpose, we compared in vitro development of synchronic (Sync) or asynchronic (Async) and asynchronic with a tetraploid (Async4n) aggregation of domestic cat IVF embryos. Furthermore, aggregated blastocyst quality was analyzed by evaluation of the total cell number, cell allocation by mitotrackers staining of embryonic cells, expression of Oct4, Nanog, Sox2, Cdx2 genes, number of OCT4+ nuclei, and presence of DNA fragmentation. Additionally, the developmental rates of Async4n aggregation of domestic cat with Leopardus geoffroyi hybrid (hLg) embryos were evaluated. Async aggregation increased blastocyst cell number and the number of OCT4+ nuclei as compared to non-aggregated diploid (2n) and tetraploid (4n) embryos. Moreover, blastocysts produced by Async4n aggregation showed reduced rates of fragmented DNA. No differences were found in the expression of the pluripotent genes, with exception of the Cdx2 expression, which was higher in 4n and aggregated embryos as compared to the control group. Interestingly, hybrids embryos derived by Async4n aggregation with domestic cat embryos had similar rates of blastocysts development as the control. Altogether, the findings support the use of two-cell-fused embryos to generate tetraploid blastomeres and demonstrate that Async4n aggregation generates good quality embryos.
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Wilsher, Sandra, i W. R. Allen. "Uterine influences on embryogenesis and early placentation in the horse revealed by transfer of day 10 embryos to day 3 recipient mares". REPRODUCTION 137, nr 3 (marzec 2009): 583–93. http://dx.doi.org/10.1530/rep-08-0328.
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Eight day 10 horse embryos were transferred non-surgically to recipient mares that had ovulated 7 days after the donors. The embryonic vesicle was seen ultrasonographically in all eight recipients, and three out of eight (38%) of the vesicles developed an embryo proper with a beating heart. Conceptus expansion was initially slower than that in control mares but continued until day 22 (recipient day 15). Time of fixation of the vesicle was related to its diameter, rather than uterine stage. Although the embryo proper first appeared ultrasonographically on day 22, as normal, it grew more slowly and the allantois expanded more slowly than that in control mares with normal pregnancies. The development of endometrial cups and their secretion of equine chorionic gonadotropin in the two mares allowed to remain pregnant to >50 days occurred at a conceptus age ∼7 days later than that in the control mares. The results demonstrated the uniqueness of the horse conceptus in being able to overcome a 7-day asynchrony with the uterus, and also highlighted the overriding influence of the uterine environment on conceptus development in the mare.
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Choi, K., E. A. Park, Y. Cho, H. S. Choi, S. Choe, R. Kim, T. K. Yoon i in. "Efficiancy of all frozen embryo transfer in IVF cycles with late developing blastocyst: improve the asynchrony between the embryo and endometrium". Fertility and Sterility 108, nr 3 (wrzesień 2017): e372. http://dx.doi.org/10.1016/j.fertnstert.2017.07.1085.
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Duque Rodriguez, M., A. Gambini, C. Gutnisky, L. Ratner, S. Rulli, A. Sestelo, O. Briski, R. Fernandez Martin, P. D. Cetica i D. Salamone. "24 Asynchronic tetraploid complementation and embryo quality in domestic cat and Leopardus geoffroyi hybrid embryos". Reproduction, Fertility and Development 32, nr 2 (2020): 138. http://dx.doi.org/10.1071/rdv32n2ab24.
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Fusion of 2-cell embryos generates tetraploid (4n) blastomeres with an increased commitment to trophectoderm. Complementation of embryos from endangered species with 4n blastomeres derived from a phylogenetically related domestic species could improve healthy pregnancy establishment after embryo transfer in domestic females. However, generation, development, and quality of tetraploid complemented embryos in felids remain unstudied. Therefore, our objectives were (1) to evaluate tetraploidy of 2-cell fused embryos; (2) to analyse the blastocyst cell number, distribution after synchronic (S) or asynchronic (AS) complementation, OCT4+ cells, DNA-fragmentation levels and CDX2 gene expression of IVF complemented embryos; and (3) to evaluate the developmental rates of tetraploid complemented Felis catus-Leopardus geoffroyi hybrid embryos. After ovariectomy, Felis catus oocytes were IVM and subjected to IVF. For Experiment 1 (n=66), 2-cell embryos (2n) were exposed to two 30-ms DC pulses at 8 kV cm−1 electric field in fusion media. Fused (4n) and nonfused embryos were cultured invitro in 50-μL drops of modified Tyrode's medium. Karyotype analysis was performed at Day 4. For Experiment 2 (n=24), zona-free IVF embryos were aggregated S (4-cell-2n/4-cell-2n) or AS (4-cell-2n/2-cell-2n and 4-cell-2n/1-cell-4n). For Experiment 3 (n=36), blastocysts generated by AS complementation (4-cell-2n/2-cell-2n and 4-cell-2n/1-cell-4n) were either fixed with 4% paraformaldehyde for immunofluorescence and terminal deoxynucleotidyl transferase dUTP nick end labeling assay or saved in RNA-Later for RT-qPCR analysis. For this experiment, nonaggregated 2n and 4n blastocysts were used as a control. For Experiment 4 (n=60), IVM oocytes were co-incubated with Leopardus geoffroyi and Felis catus (control) spermatozoa and then 4-cell-2n heterologous embryos were complemented with 1-cell-4n homologous IVF embryos. Data were analysed by Fisher's exact test. Our results showed that 67% of the 2-cell fused embryos were 4n. Moreover, 82% of nonfused embryos were aneuploids compared with 78% of 2n embryos in the control group. The AS complemented blastocysts (4-cell-2n/1-cell-4n and 4-cell-2n/2-cell-2n) had significantly higher cell number compared with S complemented (4-cell-2n/4-cell-2n) or noncomplemented embryos. The AS complementation also increased the number of OCT4+ cells independently of the ploidy of the embryos. Interestingly, AS tetraploid complemented embryos had significantly lower number of cells with fragmented DNA. No differences were found in CDX2 expression among complemented embryos; however, noncomplemented 2n blastocysts showed a significantly lower expression compared with the others group. Finally, we observed that AS complementation of 2n hybrid embryos with 4n homologous embryos reached similar blastocyst rates, 70 and 88%, respectively. Our findings support the use of 2-cell fused embryos to generate 4n blastomeres and demonstrated that tetraploid complementation generates good quality embryos, providing evidences that encourage the use of this technology to improve the developmental competence of interspecific embryos after transfer.
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Sun, Kecheng, Qinghua Zeng, Jianye Liu i Shouyi Wang. "Fault Detection of Resilient Navigation System Based on GNSS Pseudo-Range Measurement". Applied Sciences 12, nr 11 (24.05.2022): 5313. http://dx.doi.org/10.3390/app12115313.
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Because of the resilient frame structure, the factor graph is often used in navigation systems to solve the sensor asynchrony problem and realize plug-and-play effectively in the navigation information fusion method. To improve the fault detection performance of resilient integrated navigation systems under complex interference environments, a fault detection method in factor graph navigation framework based on INS measurements and GNSS pseudo-range measurements is proposed in this paper. The proposed method can effectively locate the fault satellite pseudo-range information based on the Chi-square fault detection method. Due to the plug-and-play characteristic of the factor graph framework, this method can quickly isolate faults to improve navigation accuracy. Finally, the effect of the method is verified by simulation and experiment. Compared with the Chi-square fault detection method, positioning accuracy is improved by more than 40%.
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Pandey, Tulika, Deepak Garg i Manoj Madhava Gore. "Structured P2P Overlay of Mobile Brokers for Realizing Publish/Subscribe Communication in VANET". Scientific World Journal 2014 (2014): 1–12. http://dx.doi.org/10.1155/2014/136365.
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Publish/subscribe communication paradigm provides asynchrony and decoupling, making it an elegant alternative for designing applications in distributed and dynamic environment such as vehicular ad hoc networks (VANETs). In this paradigm, the broker is the most important component that decouples other two components, namely, publisher and subscriber. Previous research efforts have either utilized the deployment of distributed brokers on stationary road side info-stations or have assigned the role of broker to any moving vehicle on ad hoc basis. In one approach, lots of preinstalled infrastructures are needed whereas, in another, the quality of service is not guaranteed due to unpredictable moving and stopping patterns of vehicles. In this paper, we present the architecture of distributed mobile brokers which are dynamically reconfigurable in the form of structured P2P overlay and act as rendezvous points for matching publications and subscriptions. We have taken city buses in urban settings to act as mobile brokers whereas other vehicles are considered to be in role of publishers and subscribers. These mobile brokers also assist in locating a vehicle for successful and timely transfer of notifications. We have performed an extensive simulation study to compare our approach with previously proposed approaches. Simulation results establish the applicability of our approach.
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Rodriguez, M. D., A. Gambini, A. Sestelo, O. Briski, R. Fernandez-Martin i D. F. Salamone. "81 Generation of presumptive domestic cat tetraploid embryos and its application for asynchronic complementation with diploid blastomeres". Reproduction, Fertility and Development 31, nr 1 (2019): 166. http://dx.doi.org/10.1071/rdv31n1ab81.
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Tetraploid complementation has been extensively used to verify the pluripotency of stem cells and also for improving placenta formation when tetraploid embryos are aggregated synchronously or asynchronously with diploid (2n) embryos. Generation of tetraploid embryos can be achieved by the electric fusion of a 2-cell embryo. However, the optimal electric intensity pulse to generate tetraploid embryos has not been studied in the feline. The aims of this study were to (1) evaluate the optimal fusion conditions to achieve the highest fusion rate without affecting embryo developmental competence, (2) compare the in vitro development of synchronic and asynchronic aggregated domestic cat IVF embryos, and (3) assess pre-implantation development of embryos generated by asynchronic complementation of presumptive 1-cell tetraploid embryos with diploid blastomeres. Domestic cat cumulus-oocyte complexes were matured in vitro on 21% O2 in air at 38.5°C for 22h. The IVF embryos were generated by co-incubation of in vitro-matured oocytes with 2×106 motile spermatozoa mL−1 on 21% O2 in air at 38.5°C for 18 to 20h. After 24h of IVF, 2-cell embryos were selected. For Experiment 1, membrane fusion of 2-cell IVF embryos (n=164) was performed with two 30-ms DC pulses at different electric field (0.8, 2, 4, and 8 kV/cm) in fusion media (Mannitol, MgSO4, CaCl2, and polyvinyl alcohol). Presumptive fused embryos and nonfused were cultured in vitro in 50-µL drops of modified Tyrode’s medium on 6.5% CO2 in air at 38.5°C (Pope et al. 2006 Methods in Molecular Biology 254, 227-244). Cleavage was determined 24h after pulse. For Experiment 2, zona pellucida-free IVF embryos (n=110) were synchronically (two 4-cell embryos) or asynchronically (one 4-cell embryo and one 2-cell embryo) aggregated in 1 microwell. For Experiment 3, 1-cell presumptive tetraploid embryo (2-cell fused embryo) was asynchronically complemented with a 4-cell embryo (n=38). For all experiments, blastocyst stage was evaluated at Day 8, and embryos presenting more than one structure per microwell were considered non-aggregated. Data were analysed by Fisher’s exact test using GraphPad Prism 6.0 (GraphPad Inc., San Diego, CA, USA), and differences were considered significant at P<0.05. The highest fusion rates (30 and 46%) with the best developmental competence (31 and 46%) were observed with 4 and 8 Kv/cm electric pulses, respectively. Electric fusion did not affect the embryo developmental competence. We observed that synchronic and asynchronic complementation reached similar blastocysts rates (54 and 65%, respectively), indicating that both techniques are suitable for tetraploid embryo complementation. Finally, when presumptive tetraploid embryos were asynchronically complemented with diploid blastomeres, the high blastocyst rate (90%) was obtained from embryos that form only one structure (aggregated embryos). Further experiments will be performed to track the distribution of cells using mitotrackers after complementation using tetraploid IVF and diploid somatic cell nuclear transfer embryos.
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Minnaard, Vivian Aurelia. "Science Scientific Knowledge and COVID 19 in the Chair of Scientific Research Methodology". Journal La Edusci 2, nr 6 (19.01.2022): 7–12. http://dx.doi.org/10.37899/journallaedusci.v2i6.529.
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The objective of this work was: To investigate the degree of participation of medical students from a privately managed university in the city of Mar del Plata, Argentina, in the recovery activity in October 2021 and the associations they make between the topics presented.The research was developed in a descriptive way with a non-experimental design. The practical work was proposed for the students to do it asynchronously within a week, with daily monitoring by the teaching team. The sample selected in a non-probabilistic way for convenience is 16 fourth-year students studying MethodologyThe most frequent characteristics of the scientific knowledge identified by the students were descriptive, explanatory and predictive It is striking that none recognized the provisional nature of the knowledge that flowed permanently with the information provided by the sources consulted.It is interesting to note that the number of views was 200, therefore if an average per student of 12.5 views of this resource available on the web offers the possibility of a truly enriching exchange. As heads of chairs such as Methodology where students begin to go through the steps of an investigation,it is necessary to look for alternatives within the available resources that motivate students, generating curiosity, synergy and proactivity. Promoting spaces for the exchange of opinions, information transfer is key to strengthen skills associated with critical thinking and communication. New technologies by providing the possibility of asynchrony and synchrony allow a fluidity in the exchanges between the teaching body and the students.
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Ran, Yue, Hongying Tang, Baoqing Li i Guohui Wang. "Self-Supervised Video Representation and Temporally Adaptive Attention for Audio-Visual Event Localization". Applied Sciences 12, nr 24 (9.12.2022): 12622. http://dx.doi.org/10.3390/app122412622.
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Localizing the audio-visual events in video requires a combined judgment of visual and audio components. To integrate multimodal information, existing methods modeled the cross-modal relationships by feeding unimodal features into attention modules. However, these unimodal features are encoded in separate spaces, resulting in a large heterogeneity gap between modalities. Existing attention modules, on the other hand, ignore the temporal asynchrony between vision and hearing when constructing cross-modal connections, which may lead to the misinterpretation of one modality by another. Therefore, this paper aims to improve event localization performance by addressing these two problems and proposes a framework that feeds audio and visual features encoded in the same semantic space into a temporally adaptive attention module. Specifically, we develop a self-supervised representation method to encode features with a smaller heterogeneity gap by matching corresponding semantic cues between synchronized audio and visual signals. Furthermore, we develop a temporally adaptive cross-modal attention based on a weighting method that dynamically channels attention according to the time differences between event-related features. The proposed framework achieves state-of-the-art performance on the public audio-visual event dataset and the experimental results not only show that our self-supervised method can learn more discriminative features but also verify the effectiveness of our strategy for assigning attention.
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Skidmore, Julian A., M. Billah i W. R. Allen. "Investigation of factors affecting pregnancy rate after embryo transfer in the dromedary camel". Reproduction, Fertility and Development 14, nr 2 (2002): 109. http://dx.doi.org/10.1071/rd01100.
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The uteri of 36 adult dromedary camels were flushed non-surgically three times each with 90–120 mL of embryo flushing medium 7 days after ovulation. A total of 242 embryos were recovered, of which 139 were transferred non-surgically to recipient camels that were either at different levels of synchrony with respect to the Day 7 donor (+1 to –3 days; n = 58), or were at Day 6 after ovulation, but received one of the following treatments: (i) none (controls, n = 15); (ii) 150 mg progesterone-in-oil injected intramuscularly once daily during Days 5–20 after ovulation inclusive (n = 16); (iii) 500 mg flunixin meglumine given intravenously 15 min before transfer of the embryo (n = 6); (iv) 20 μg of the gonadotrophin-releasing hormone (GnRH) analogue buserelin given on Day 5 after ovulation (n = 12); or (v) the embryo was cooled to 4˚C and held at this temperature in an insulated container for 24 h before being transferred (n = 32). Jugular vein blood samples, taken daily from all the recipient camels during Days 0–20 after ovulation, were assayed for progesterone concentration and closely timed serial samples taken from the camels receiving flunixin meglumine or GnRH were assayed for 13,14-dihydro-15-keto prostaglandin F2α (PGFM) or oestradiol concentrations. The pregnancy rate increased to a maximum of 67% when ovulation in the recipient was negatively synchronized to have occurred 1 day behind that in the donor, and it fell dramatically when the level of asynchrony between recipient and donor increased to +1 (9%) or –3 (10%) days. It was not improved by daily injections of progesterone (44%), flunixin meglumine given before transfer (16%), or GnRH given on Day 5 (33%). Of the 32 embryos that were cooled to 4˚C before being transferred to Day 6 recipients, 20 resulted in pregnancies (63%) to give a success rate similar to that attained with the control fresh embryos (67%). Serum progesterone concentrations in the recipients increased to a mean ± SEM of 2.6 ± 0.8 ng mL–1 by Day 8 after ovulation and, in those that were pregnant, levels remained elevated at 3–5 ng mL–1 for the remainder of the sampling period; in non-pregnant recipients the concentrations declined to <1 ng mL–1 by Day 11. Plasma PGFM concentrations in the flunixin meglumine-treated camels remained low (40–90 pg mL–1) compared with those in the untreated control camels, in which peak values of around 180 pg mL–1 were reached within 10 min after transfer after which a steady decline occurred until resting concentrations of 90–100 pg mL–1 were reached by 110 min after transfer. Treatment with GnRH on Day 5 after ovulation produced a transitory increase in serum oestradiol-17β concentrations for 24 h. However, from Day 8, oestradiol concentrations in both the GnRH-treated and the untreated camels increased steadily to reach 2.5–3.5 pg mL–1 by Day 12.
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Hroch, Miroslav. "Obecné, světové, globální dějiny?" Dějiny – teorie – kritika, nr 2 (3.04.2023): 270–74. http://dx.doi.org/10.14712/24645370.2882.
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Autor v návaznosti na diskusní příspěvek Jana Horského „Obecné dějiny“, „obsahová filozofie dějin“ a evoluční teorie ohledává proměny vztahu české historiografie k pojmu obecné dějiny od 60. do 90. let 20. století, přičemž upozorňuje na komplikovaný vztah českých národních dějin k dějinám ne-národním, resp. mimonárodním. Spolu s tím autor předkládá šest způsobů žánrového vymezení mimonárodních dějin s důrazem na jejich náročnost a přínos, resp. na jejich možné slabiny: syntézy; monografické analýzy; dějiny mezinárodních vztahů; historické zpracování tzv. vztahových témat, která se váží k národním dějinám, jež mohou být kulturní, politické i hospodářské; pramenné studie zkoumající dílčí témata z dějin jiných „ne-národních“ zemí a regionů na základě nových pramenů; analýza a výklad procesů sociálních, ekonomických či kulturních proměn, které proběhly v několika zemích, synchronně či asynchronně. Právě onen poslední žánr autor považuje za shodný s termínem „obecné dějiny“ v pojetí Jana Horského. Sám se však spíše kloní k užívání pojmů transnacionální, komparativní dějiny, historii transferu či l’histoire croisée, a naopak se negativně vymezuje vůči pojmu globální dějiny. Důraz přitom klade na rozdílnou povahu zkoumaných procesů a proměn a na rozdílnou podobu metodologických otázek, které si historikové obecných dějin kladou. Práce na obecných dějinách podle autora preferuje makroanalýzu (i když neodmítá mikroanalýzu), ve značné míře se opírá o mimopramenné poznání, aplikuje či měla by aplikovat nepřímou metodu. Pracuje tedy do velké míry s výsledky sekundární literatury a je na její úrovni závislá. Hledá a kombinuje souvislosti, nepovažuje za primární úkol zjišťovat dosud neznámé informace. Neomezuje se představou o jedinečnosti historických jevů. Dává přednost analýze před narací.
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Giraldo, A. M., J. W. Lynn, C. E. Pope, R. A. Godke i K. R. Bondioli. "34 LIFESPAN AND CHROMOSOMAL STABILITY OF BOVINE AND PORCINE FETAL FIBROBLAST CELLS CULTURED IN VITRO". Reproduction, Fertility and Development 17, nr 2 (2005): 167. http://dx.doi.org/10.1071/rdv17n2ab34.
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The low efficiency of nuclear transfer (NT) has been related to factors such as mitochondria heteroplasmy, failure of genomic activation, and asynchrony between the donor karyoplast and recipient cytoplast. Few studies have characterized donor cell lines in terms of proliferative capacity and chromosomal stability. It is known that suboptimal culture conditions can induce chromosomal abnormalities, and the use of aneuploid donor cells during NT can lead to a high incidence of abnormal cloned embryos (Giraldo et al. 2004 Reprod. Fertil. Dev. 16, 124 abst). The purpose of this study was to determine the lifespan and chromosomal stability of bovine and porcine fetal cells. Four bovine and four porcine fibroblast cells lines were established from 50-day and 40-day fetuses, respectively. Cells were cultured in DMEM medium supplemented with 10% fetal bovine serum and 1% penicillin and streptomycin at 37°C in 5% CO2. Each cell line was passaged to senescence. Total population doublings (PDs) and cell cycle duration were calculated. To determine the chromosome numbers at different PDs, cells were synchronized in metaphase, fixed, and stained. ANOVA and chi-square tests were used to analyze differences in PDs and proportion of aneuploid cells between cell lines, respectively (P < 0.05). The results show that proliferative capacity was not different between cell lines derived from the same species. Cell lines derived from bovine and porcine fetuses had different in vitro lifespans (33 PDs vs. 42 PDs, respectively; P < 0.05). The mean length of the cell cycles for both bovine and porcine fetal fibroblasts was ∼28 h. The percentage of aneupliod cells in both bovine and porcine fetal cell lines increased progressively with duration of culture (see Table) and was high throughout the study. The proliferative capacity of cultured cells was similar within individuals of the same species, but growth characteristics differed between fetal bovine and porcine cell lines. The progressive increase of aneuploid cells could be due to suboptimal culture conditions or unusual chromosome instability in the particular fetuses used. These data demonstrate the importance of determining chromosome content and the use of cells at early passages to decrease the percentage of aneuploid reconstructed embryos and increase the efficiency of NT.
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Chung, Yang Jo, Chul Won Choi, Christopher Slape, Terry Fry i Peter D. Aplan. "A NUP98-HOXD13 Fusion Gene Induces a Transplantable Myelodysplastic Syndrome in Mice." Blood 110, nr 11 (16.11.2007): 401. http://dx.doi.org/10.1182/blood.v110.11.401.401.
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Abstract The myelodysplastic syndromes (MDSs) are a group of hematologic stem cell disorders characterized by ineffective hematopoiesis and dysplasia. A large number of chromosomal aberrations including deletions, amplifications, inversions, and translocations, some of which involve the NUP98 gene, have been associated with MDS. Recently an MDS mouse model expressing a NUP98-HOXD13 (NHD13) fusion gene was developed, which faithfully recapitulates all of the key features of MDS. Although it is well-established that acute myeloid leukemia (AML) is transplantable, there is no evidence that MDS is a transplantable condition. Therefore, in order to develop evidence for MDS as a hematopoietic stem cell (HSC) disease, we attempted to transfer MDS to normal recipients through bone marrow transplantation (BMT). All the recipients transplanted with bone marrow (BM) cells from NHD13 mice with MDS showed anemia, leukopenia, lymphopenia, and neutropenia when compared to recipients of wild-type (WT) littermates. The homing efficiency of the NHD13 primitive progenitor cells (Lineage negative [Lin−], Sca-1+) was about 2 fold higher than WT, and there was no significant difference in BM cellularity between the recipients of NHD13 and WT BM, indicating that the NHD13 recipients had ineffective hematopoiesis. These phenomena were reproduced in secondary recipients using primary recipients of NHD13 BM as donor mice. In secondary transplantation assays, 3 out of 5 recipients developed acute myeloid leukemia (AML) at 16 weeks post-transplantation. Morphological features of MDS, including nuclear-cytoplasmic asynchrony, binucleate cells, hypersegmented neutrophils, and giant platelets were detected in BM and peripheral blood of NHD13 donor, primary and secondary recipients by cytospin preparations. In competitive repopulation assays, mice transplanted with equal numbers of WT and NHD13 BM cells showed a decreased percentage of NHD13 cells in the peripheral blood, but an increased percentage of NHD13 cells in the BM, again providing evidence of ineffective hematopoiesis of the NHD13 cells. The transplantation of lineage depleted cells from BM has shown that the transplantable cells for MDS reside in the Lin− population of NHD13 BM. These findings demonstrate that MDS can be transferred to healthy recipients by BMT, supporting the concept that MDS originates in a transplantable multilineage hematopoietic stem cell.
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Skikevych, M. Н., L. І. Voloshyna, K. Р. Lokes i V. М. Havryliev. "FEATURES OF DISTANCE LEARNING IN MEDICINE". Ukrainian Dental Almanac, nr 4 (25.12.2023): 102–7. http://dx.doi.org/10.31718/2409-0255.4.2023.17.
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Abstract. The issue of the use of distance learning in medical educational institutions remains debatable. The advantages of distance education include the ability to educate a large number of students simultaneously. Considering a competency-based approach to professional training, the new role of the higher education instructor in the educational process is determined by us. Instead of being a passive consumer of knowledge, they need to become an active participant who thinks critically, plans their independent work, shows initiative, and can formulate questions and find solutions. The acquisition of practical skills is the main component during the training of future dentists. Unfortunately, this task cannot be solved in this way. In our article, we tried to review research on the use of remote technologies and their effectiveness in medical education in general and dentistry in particular.
The aim of this study is to analyze the possibilities and prospects of the use of distance learning in medical education.
Main part. Features of modern medical education are the following: an increase in the percentage of independent work of students in the learning process, the wide use of interactive forms. A deep understanding of the subject matter necessitates the application of modern digital technologies, which grant students full and unrestricted access to a vast volume of material. The primary advantages of distance learning encompass flexibility, modularity, parallelism, asynchrony, scalability, cost-effectiveness, social integration, and international reach. Incorporating both traditional and distance learning components contributes to the enhancement of the professional competence of both educators and students. This transition leads to the creative and professional development of future healthcare professionals, fundamentally shifting the paradigm of conventional education, where students become active participants in the learning process.
Conclusions. The introduction of new innovative approaches with elements of distance learning allows to transfer the learning process to a qualitatively new level, increase the level of students’ competence and promote their active participation in the educational process. It should be emphasized that the process of wide introduction of distance learning technologies is more appropriate at the stage of postgraduate education of medical workers. And in the structure of undergraduate education, this form can be an addition to practical classes.
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Chen, W. C., J. Zhu, P. Fisher, D. Amarnath i K. H. S. Campbell. "235 A COMPARISON OF PARTHENOGENETIC DEVELOPMENT OF PORCINE OOCYTES SYNCHRONISED DURING MATURATION BY CYCLOHEXIMIDE OR cAMP". Reproduction, Fertility and Development 21, nr 1 (2009): 215. http://dx.doi.org/10.1071/rdv21n1ab235.
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In vitro maturation of porcine oocytes is characterized by a high level of asynchrony between oocytes. Previous studies reported that cycloheximide (CHX) and 3′, 5′-cyclic AMP (cAMP) synchronize porcine oocytes and improve development to blastocyst stage following IVF or have been used for somatic cell nuclear transfer (SCNT) (Ye et al. 2005 Biol. Reprod. 72(2), 399–406; Betthauser et al. 2000 Nat. Biotechnol. 18(10), 1055–1059). We previously reported that cAMP was more effective than CHX in synchronizing porcine oocyte maturation, producing MII oocytes in a shorter time window and providing a more homogenous population for future SCNT studies (Chen et al. 2008 SRF conference, 2008 abst, p34). Here we compared parthenogenetic development of porcine oocytes synchronized by these two treatments. Selected cumulus–oocyte complexes (COC) obtained from slaughtered gilts were randomly divided into three groups and cultured at 39°C, 5% CO2 in air in modified NCSU-23 medium (with 1 μm glutathione, 1 mm cysteine, 5 mg L–1 insulin, 10 ng mL–1 epidermal growth factor, 10% (v/v) porcine follicular fluid, 1% essential and 0.5% nonessential amino acids) ± hormones (10 IU mL–1 PMSG and 10 IU mL–1 hCG): (1) with hormones for the first 22 h and then without hormones until 44 h; (2) with hormones and 5 μg mL–1 CHX for 12 h, and then with hormones but no CHX until 44 h; (3) with hormones and 1 mm cAMP for 22 h, and then without hormones and cAMP until 44 h. Parthenogenetic development of cycloheximide and cAMP treated oocytes was compared by cleavage rate at 48 h postactivation (hpa) and blastocyst formation at 168 hpa. No significant differences were observed in the frequency of cleavage (96.7 ± 2.1% v. 81.4 ± 11.6% v. 84.5 ± 5.7%), development to blastocyst (28.3 ± 11.4% v. 27.1 ± 5.7% v. 32.8 ± 5.3%) between control, CHX or cAMP treated oocytes, respectively (chi-square test, P > 0.05). However, total cell number was significantly higher in the CHX group than cAMP group (42.7 ± 4.1 v. 31.8 ± 2.0, respectively; t-test, P < 0.05). The results demonstrate that synchronization of porcine oocytes by treatment with CHX or cAMP does not affect subsequent parthenogenetic development if judged by the blastocyst formation, although the meaning of the difference of total cell numbers between CHX and cAMP treatments is still unclear.
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Nikolaev, V. V. "Indigenous Turkic-Speaking Peoples and the Urbanization of Southern Siberia (20<sup>th</sup> – Early 21<sup>st</sup> Century)". Vestnik NSU. Series: History and Philology 23, nr 5 (24.05.2024): 156–67. http://dx.doi.org/10.25205/1818-7919-2024-23-5-156-167.
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Purpose. This article integrates studies relating to the history of urban communities of the Southern Siberian indigenous peoples (Altaians, Chelkans, Khakasses, Kumandins, Shors, Telengits, Teleuts, Tozhu Tuvans, Tubalars, Tuvans). A multidisciplinary approach to urbanization processes was used; their stages, rates, causes, and principal characteristics were analyzed. The database consists of our own field findings, published results of sociological studies, and those of All-Union and All-Russian population censuses.Results. During the 19th century, the prerequisites for the urbanization of the indigenous Turkic-speaking peoples of Southern Siberia were laid. There are three stages of urbanization of the indigenous peoples of Southern Siberia: 10) up to the middle of the twentieth century; 2) the 1950s–1980s (for the Shorians it is 1930s–1980s); 3) from the 1990s to the present. At the first stage of urbanization representatives of the indigenous population of the region moved to the city mainly in order to improve the level of education and within the framework of the policy of forming national personnel. At the next stage, during the period of industrial development of the eastern regions, there was an intensification of urbanization among a number of peoples (Shors, Teleutes and Kumandins) who lived near industrial centers. Industrial development was accompanied, among other things, by the transfer of rural settlements to urban ones, as well as the absorption of villages during the expansion of urban boundaries; since the 1990s, the reverse process began. At the last stage, educational strategies play a decisive role. The liquidation of unpromising villages in the middle of the 20th century affected primarily small populations, contributing to the growth of migration to cities. Cities are beginning to attract representatives of indigenous small-numbered peoples (Telengites, Tubalars, Chelkans and since the 2010s Tuvinians-Todzhins), whose territory of traditional residence is located at a considerable distance from large settlements. The share of townspeople among Altaians, Tuvinians and Khakas during the 20th century grew gradually, which was associated with a relatively less intensive industrial development of their territories of residence.Conclusion. The peculiarities of urban population formation among the indigenous peoples of Southern Siberia are: asynchrony of urbanization; orientation of Aboriginal migrations to the nearest cities and urban-type settlements; incompleteness of urbanization not only in terms of qualitative, but also quantitative characteristics. With the exception of the Shors and Kumandins, the rest of the indigenous peoples of the region remain poorly and medium-urbanized.
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Simmet, K., M. Reichenbach, S. Jung, R. Fries, T. Grupp, C. Gschöderer, J. Scherzer, H. D. Reichenbach i E. Wolf. "84 PAIRS OF BLASTOMERES FROM BOVINE DAY 5 MORULAE ARE ABLE TO CONTRIBUTE TO INNER CELL MASS AND TROPHECTODERM IN CHIMERIC EMBRYOS GENERATED BY AGGREGATION WITH TWO DAY 4 MORULAE". Reproduction, Fertility and Development 27, nr 1 (2015): 135. http://dx.doi.org/10.1071/rdv27n1ab84.
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The multiplication of high-value embryos by chimera formation using asynchronic aggregation is a promising alternative to embryonic cell nuclear transfer. Single blastomeres from a donor embryo are aggregated with 2 host embryos, thus several chimeras can be constructed per donor embryo. Due to the advanced developmental stage, the donor blastomeres are likely to contribute to the inner cell mass (ICM) and later give rise to the embryo proper, whereas the host embryos form extra-embryonic tissues. To test if pairs of blastomeres from Day 5 morulae are able to form the ICM when aggregated with 2 Day 4 host embryos, we produced transgenic donor embryos carrying a fluorescent reporter gene (enhanced green fluorescent protein, eGFP) by using semen from an eGFP transgenic bull (Reichenbach et al. 2010 Transgenic Res. 19, 549–556) for in vitro fertilization and in vitro host embryos produced by a standard procedure. The zona pellucida of all embryos was removed by treatment with 1 mg mL–1 pronase. Donor embryos were assessed for eGFP expression by fluorescence microscopy and disaggregated by gentle pipetting after incubation in Mg2+- and Ca2+-free medium. Pairs of blastomeres were then placed between 2 host embryos and cultured individually in a well-of-the-well culture dish. On Day 6 after aggregation, fully developed blastocysts were assessed for eGFP fluorescence. In 3 replicates, n = 30 chimeras were produced by aggregation; 13 (43%) developed to blastocysts, of which 2 (15%) showed local eGFP expression in the ICM and 7 (54%) showed a generalized expression. From the results of this study we conclude that Day 5 morulae may be multiplied in an efficient manner by using the chimera formation technique, which makes this approach applicable to ex vivo-derived embryos. In future investigations we will study the effect of using donor blastomeres from either the inside or outside of the donor morula and test the use of tetraploid host embryos to increase the rate of blastocysts with the desired genotype in the ICM. Finally, we aim to introduce this multiplication approach to the production of genotyped embryos with a genomic estimated breeding value (gEBV) and intend to produce calves with identical gEBV.Funded by the Bavarian Research Foundation (AZ-1031–1).
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Patil, Madhuri. "What is the Optimum Endometrium Needed for Implantation?" Fertility & Reproduction 05, nr 04 (grudzień 2023): 290. http://dx.doi.org/10.1142/s2661318223741048.
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Implantation most critical step in reproduction. A complex process where blastocyst becomes intimately connected with maternal endometrium/decidua and requires; Competent embryo at blastocyst stage Receptive endometrium Synchronized dialogue between maternal and embryonic tissues Endometrial Changes for Implantation include architectural, morphological, cytochemical, molecular and genetic. These Changes Induce Endometrial receptivity, which is endometrial lining in a state of readiness for blastocyst implantation. It involves acquisition of adhesion ligands and loss of inhibitory components that may act as a barrier to an attaching embryo. Receptive endometrium is capable of selecting good quality embryos and reject the incompetent embryos. Endometrial Evaluation includes 1. Non-Invasive Assessment of Endometrial Receptivity by USG 2. Detection of abnormal Uterine cavity by 3D USG/SIS, HSG and Hysteroscopy 3. Diagnose Chronic Endometritis by hysteroscopy and Molecular tests? 4. Endometrial Microbiome by molecular tests 5. Endometrial asynchrony - Proteomics and transcriptomics 2D and 3D Ultrasound can Identify patients with poor implantation prognosis but has low predictive value in determining endometrial receptivity and IVF outcome. Ideal endometrial thickness for optimal outcome is between 7-14 mm. No Association was seen between clinical pregnancy rates (CPR) and endometrial pattern for women undergoing in IVF with fresh ET and FET. Minimum Endometrial Volume associated with pregnancy is 1.59 mL – 3D. But most pregnancies occur in volumes of 2-13 mL. Evaluation of endometrial volume is particularly useful in synechiae, adenomyosis and uterine anomalies. Vascularity demonstrated within Zone 3 or within Zones 3 and 4 prior to transfer is associated with good implantation rate. Presence of >3 peristaltic contractions of the sub endometrial myometrium/2 minutes interval on Day of hCG administration associated with poor implantation. Diagnosis of chronic endometritis is based on hysteroscopy, endometrial biopsy with plasma cells being identified histologically and specific treatment is determined based on microbial culture. Existence of non-Lactobacillus bacteria in the endometrium is correlated with negative impacts on reproductive function and should be considered as an emerging cause of implantation failure and pregnancy loss. Endometrial Receptivity Array (ERA) is validated for analysing the expression of 238 genes that are intimately related to endometrial receptivity. Abnormality in endometrial receptivity is displayed a specific gene expression profile. Intrauterine secretory profile directly linked to successful implantation and evaluation of endometrial fluid for cytokine, interleukin and growth factor secretions can be used to assess the endometrium. Conclusion: Identification of one or more of endometrial parameters that definitely indicate receptivity for implantation remains an elusive goal. None of the endometrial receptivity markers have sufficient discriminatory value to act as a diagnostic test for endometrial receptivity based on their ability to predict clinical pregnancy. Due to the dynamic, cyclic nature of the endometrium it may be difficult, to reliably assess endometrial function on the basis of a single test.
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Garcia Guerra, A., G. A. Bó, J. Villarreal i G. M. Brogliatti. "295 SUPEROVULATORY RESPONSE IN COWS FOLLOWING SYNCHRONIZATION OF FOLLICLE WAVE EMERGENCE WITH ESTRADIOL AT DIFFERENT STAGES OF THE ESTROUS CYCLE". Reproduction, Fertility and Development 20, nr 1 (2008): 227. http://dx.doi.org/10.1071/rdv20n1ab295.
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Ovarian asynchrony and variability in response to superstimulation remain the most limiting factors in any embryo transfer program (Armstrong D 1993 Theriogenology 39, 7–24). Ovarian response can be increased and less variable if superstimulatory treatment is started at the time of follicular wave emergence (Bö GA et al. 1995 Theriogenology 43, 31–40). A combination of progesterone (P4) and estradiol have been used to synchronize follicular wave for superstimulation. A retrospective analysis was done to compare the ovarian response, superovulatory response and embryo production of cows in Argentina that received progesterone and estradol prior to superstimulation at different stages of the estrous cycle. This research was carried out using different breed of donors (n = 584, 88% Angus) during the last 4 years in Buenos Aires province, Argentina. Heat detection was performed twice a day. At random stages of the estrous cycle, donors received an intravaginal progesterone device (DIB; Syntex, Buenos Aires, Argentina), 2 mg of estradiol benzoate and 50 mg of progesterone (Syntex, Buenos Aires, Argentina) IM on the same day. On day 4 after DIB insertion, superestimulatory treatment was initiated on a decreasing dose regimen of FSH (Pluset; Callier, Spain, or Folltropin, Bioniche Animal Health Inc., Belleville, Ontario, Canada) as IM injections every 12 h over 4 d. On day 6, DIBs were removed, and cows received two doses of 2 mL of cloprostenol 12 h apart. At heat detection, all donors received a dose of 2 mL of GnRH (Dalmarelin; Fatro Von Franken, Buenos Aires, Argentina) by IM injection and were inseminated 12 and 24 h later. Seven days later, embryo collection was performed and ovarian response was evaluated as number of CL + unovulated follicles by transrectal ultrasound using a 7.5-MHz transducer (Pie Medical, Maastricht, the Netherlands). Ova/embryos were evaluated and classified according to the IETS manual. Donors were assigned to receive DIB and estradiol during the following stages of the cycle: group 1: between days 4 and 7 post-estrus (dominant follicle period), group 2: between days 8 and 12 post-estrus (emergence of the second follicular wave), and group 3: between days 13 and 21 post-estrus (dominant follicle of the second wave). Kruskal-Wallis test was used to compare variables among groups, and results are shown in Table 1. Ovarian response as CL + unovulated follicles and number of ovulations were significantly different among groups (P < 0.05). However, there was no significant difference in the number of fertilized ova or transferable embryos. Nevertheless, numeric differences that show that group 2 (started between days 8 and 12 post-estrus) was always superior for all variables. In conclusion, data suggest that estradiol may be more effective in synchronizing follicle wave emergence for superstimulation during the mid-part of the estrous cycle. Table 1. Superovulatory response in cows in which follicle wave emergence was synchronized with estradiol at different stages of the estrous cycle (mean ± SD) Research supported by Centro Genetico Bovino Eolia S.A.
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Meroufel, Abdelkader, Youcef Djeriri, Ahmed Massoum i Abdelhakim Hammoumi. "Commande vectorielle par les réseaux de neurones artificiels de l’énergie d’une MADA intégrée à un système éolien". Journal of Renewable Energies 13, nr 4 (25.10.2023). http://dx.doi.org/10.54966/jreen.v13i4.232.
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Le présent travail est consacré à une commande vectorielle de l’énergie active et réactive par les réseaux de neurones d’une machine asynchrone à double alimentation (MADA) intégrée à un système éolien. Le transfert de puissance entre le stator et le réseau est réalisé par action sur les signaux rotoriques via un convertisseur bidirectionnel. Pour une étude comparative, le contrôle indépendant de la puissance active et réactive est assuré dans la première étape par des régulateurs classiques (PI) et dans la deuxième étape par des régulateurs neuronaux (RN). Les performances et la robustesse sont analysées et comparées par simulation à base du logiciel Matlab/Simulink.
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Yerushalmi, G. M., T. Shavit, S. Avraham, M. Youngster, A. Kedem, I. Gat, U. S. Dorofeyeva i in. "Day 5 vitrified blastocyst transfer versus day 6 vitrified blastocyst transfer in oocyte donation program". Scientific Reports 11, nr 1 (21.05.2021). http://dx.doi.org/10.1038/s41598-021-90238-y.
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AbstractThe superiority of day 5 blastocysts compared to day 6 blastocysts in fresh cycle transfers was previously demonstrated and attributed mainly to endometrial asynchrony. Data from frozen blastocysts transfers showed conflicting results, possibly due to heterogeneous patient population and embryo quality. The aim of this study was to compare clinical pregnancy rate (CPR) and live birth rate (LBR) between transfers of vitrified day 5 blastocysts and day 6 blastocysts in oocyte donation, blastocyst-only cycles. In a retrospective, multi-center study, with a single oocyte donation program, a total of 1840 frozen embryo transfers (FET’s) were analyzed, including 1180 day 5 blastocysts and 660 day 6 blastocysts transfers. Day 5 blastocyst transfers had better embryonic development and significantly higher CPRs (34.24% vs. 20.15%, P < 0.0001), higher LBRs (26.89% vs. 14.77%, P < 0.0001), less cycles to LBR (1.83 ± 0.08 vs. 2.39 ± 0.18, P = 0.003) and shorter time to LBRs (76.32 ± 8.7 vs. 123.24 ± 19.1 days, P = 0.01), compared to day 6 transfers, respectively. A multivariate stepwise logistic regression indicated, that day 5 transfer was an independent factor for CPRs (OR 1.91; 95% CI 1.43–2.54, P < 0.001) and LBRs (OR 2.26; 95% CI 1.19–4.28, P = 0.01), regardless of embryo quality, compared to day 6. In conclusion, day 5 blastocysts in oocyte donation program have significantly higher CPRs and LBRs, and present shorter time to delivery, compared to day 6 blastocysts, regardless of embryo quality.
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Halani, Sameer H., Cristina V. Sanchez, Austin S. Hembd, Ahneesh J. Mohanty, Joan Reisch i Shai M. Rozen. "Depressor Anguli Oris Myectomy versus Transfer to Depressor Labii Inferioris for Facial Symmetry in Synkinetic Facial Paralysis". Journal of Reconstructive Microsurgery, 17.08.2021. http://dx.doi.org/10.1055/s-0041-1732350.
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Abstract Background Postparalytic synkinesis presents with a combination of hypo- and hypertonic muscles, leading to facial asynchrony with animation and at rest. One ubiquitous finding is a hypertonic depressor anguli oris (DAO) muscle and a weak depressor labii inferioris (DLI) muscle. The goal of this study was to evaluate the utility of DAO myectomy with or without its transfer to the weakened DLI in improving critical components of the dynamic smile. Methods From 2018 to 2020, this single-center, prospective study included of postparetic facial synkinetic patients with evidence of DAO hypertonicity who underwent DAO myectomy with or without transfer to DLI. Objective facial measurements were used to compare the effectiveness of DAO to DLI transfer to pure DAO myectomy in improving asymmetry of the synkinetic hemiface. Results Twenty-one patients with unilateral postparetic facial synkinesis with DAO hypertonicity were included; 11 underwent DAO myectomy, while 10 underwent DAO to DLI transfer. Baseline demographics and facial measurements were similar between the groups. DAO myectomy resulted in increased modiolus resting position, closed-mouth smile modiolus angle and excursion, open-mouth smile modiolus angle, excursion, dental show, and decreased lower lip height deviation. DAO to DLI transfer demonstrated similar findings but lacked significant increase in excursion and resulted in worsened lower lip height deviation. Conclusion These findings illustrate the utility of DAO myectomy in improving imbalance in the synkinetic patient and necessitate further technical refinements for DAO transfers or a different approach for improving lower lip depression in this subgroup of patients.
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Duan, Xu, Yi Zhang, Yuan Liang, Yingying Huang, Jie Zhang i Hao Yan. "The effect of speech-gesture asynchrony on the neural coupling of interlocutors in interpreter-mediated communication". Social Cognitive and Affective Neuroscience, 10.05.2023. http://dx.doi.org/10.1093/scan/nsad027.
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Abstract In everyday face-to-face communication, speakers use speech to transfer information and rely on co-occurring nonverbal cues, such as hand and facial gestures. The integration of speech and gestures facilitates both language comprehension and the skill of theory of mind. Consecutive dialogue interpreting (DI) allows dyads of different linguistic backgrounds to communicate with each another. The interpreter interprets after the interlocutor has finished a turn, so the interlocutor watches the gesture first and hears the target language a few seconds later, resulting in speech-gesture asynchrony. In this study, we used the functional near-infrared spectroscopy hyperscanning technique to investigate the influence of speech-gesture asynchrony on different levels of communication. Twenty groups were recruited for the DI experiments. The results showed that when the interpreter performed consecutive interpreting, the time-lagged neural coupling at the temporoparietal junction (TPJ) decreased compared to simultaneous interpreting. It suggests that speech-gesture asynchrony significantly weakened the ability of interlocutors to understand each other’s mental state, and the decreased neural coupling was significantly correlated with the interpreter’s interpretation skill. In addition, the time-aligned neural coupling at the left inferior frontal gyrus (IFG) increased, which suggests that, as compensation, the interlocutor’s verbal working memory increases in line with the communication process.
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Gomez-Sanchez, E., D. Castelló, R. Diaz, N. Almunia, M. Valcárcel, R. Jiménez, A. M. Villaquirán, C. Diez, L. Quintero i J. A. Castilla. "P-125 Day 5 endometrium, Is the pregnancy rate following day 5 or day 6 vitrified/thawed blastocysts transfer affected?" Human Reproduction 38, Supplement_1 (1.06.2023). http://dx.doi.org/10.1093/humrep/dead093.489.
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Abstract Study question Are ongoing pregnancy rates of embryos vitrified on day 5 and day 6 when transferred into a day 5 endometrium comparable? Summary answer Day 5 blastocysts implant better in day 5.5 endometrium than day 6, whether they were vitrified on day 6 or 5 and cultured 24 hours. What is known already Preparation of the endometrium for transfer of cryopreserved embryos is usually done so that transfer takes place on endometrial day 5, although embryos may be at day 5 or 6 of development, so there may be asynchrony between the endometrium and the embryo if a day 6 embryo is transferred. Fresh transfer of day 5 blastocysts has been reported to have better results than day 6 blastocysts, predictably due to this endometrial asynchrony. However, data from frozen blastocyst transfers are less clear, possibly due to heterogeneity of the patient population and/or embryo quality. Study design, size, duration In this study we aim to analyse whether ongoing pregnancy after vitrified/thawed embryo transfers is affected if day 5 or day 6 embryos are transferred into day 5 endometrium. For this purpose, we examined 2266 cryotransfers performed in three Next Fertility clinics in Spain between 2016 and 2022. Day 5 (n = 1583) and 6 (n = 519) blastocyst transfers and day 5 embryos that devitrified one day before transfer (n = 164) were retrospectively compared. Participants/materials, setting, methods In this work blastocyst transfers were performed from donor or autologous oocytes, with or without PGT-A. Embryos were vitrified on day 5 or 6. Endometria were prepared with hormone replacement therapy or in natural cycle. All FET were performed after 5.5 days of progesterone exposure, regardless of embryo stage (day 5 or 6). The results were analysed considering all the above groups. Main results and the role of chance Ongoing pregnancy are superior with day 5 blastocysts versus day 6 and day 5 cultured for 24 hours prior to transfer. However, day 6 blastocysts were similar to cultured ones. Own oocytes: Day 5 44.98% (n = 538) vs Day 6 35.75% (n = 207) (p < 0.03); Day 5 44.98% vs Day 5 cultured 32.58% (n = 89) (p < 0.03); Day 6 35.75% vs Day 5 cultured 32.58% (p > 0.05). Donated Oocytes: Day 5 45.86% (n = 726) vs Day 6 28.51% (n = 221) (p < 0.00001); Day 5 44.98% vs Day 5 cultured 39.34% (n = 61) (p > 0.05); Day 6 28.51% vs Day 5 cultured 39.34% (p > 0.05). PGT-A Own oocytes: Day 5 51.72% (n = 203) vs Day 6 25.39% (n = 63) (p < 0.003); Day 5 51.72% vs Day 5 cultured 40.00% (n = 10) (p > 0.05); Day 6 25.39% vs Day 5 cultured 40.00% (p > 0.05). PGT-A Donated Oocytes: Day 5 42.24% (n = 116) vs Day 6 35.71% (n = 28) (p > 0,05); Day 5 42.24% vs Day 5 cultured 40.00% (n = 4) (p > 0.05); Day 6 35.71% vs Day 5 cultured 50.00% (p > 0.05). Miscarriage rates were similar across all groups. Limitations, reasons for caution Not all cohorts in the study were equally large, so some results have less statistical power, especially in abortion rates. Wider implications of the findings Day 5 blastocysts should always be transferred into a 5.5-day endometrium on the day they are devitrified, as this is when they are most synchronous with the endometrium. Further studies are needed to assess whether day 6 embryos implant better in a 6.5-day endometrium than in a 5.5-day endometrium. Trial registration number not applicable
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Tinn Teh, Wan, Alex Polyakov, Claire Garrett, David Edgar i Peter Adrian Walton Rogers. "Reduced live birth rates in frozen versus fresh single cleavage stage embryo transfer cycles: A cross-sectional study". International Journal of Reproductive BioMedicine (IJRM), 22.07.2020. http://dx.doi.org/10.18502/ijrm.v13i7.7366.
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Background: Studies have suggested that embryo-endometrial developmental asynchrony caused by slow-growing embryos can be corrected by freezing the embryo and transferring it back in a subsequent cycle. Therefore, we hypothesized that live birth rates (LBR) would be higher in frozen embryo transfer (FET) compared with fresh embryo transfers.
Objective: To compare LBR between fresh and FET cycles.
Materials and Methods: A cross-sectional analysis of 10,744 single autologous embryo transfer cycles that used a single cleavage-stage embryo was performed. Multivariate analysis was performed to compare LBR between FET and fresh cycles, after correcting for various confounding factors. Sub-analysis was also performed in cycles using slow embryos.
Results: Both LBR (19.13% vs 14.13%) and clinical pregnancy (22.48% vs 16.25%) rates (CPR) were higher in the fresh cycle group (p < 0.00). Multivariate analysis for confounding factors also confirmed that women receiving a frozen-thawed embryo had a significantly lower LBR rate compared to those receiving a fresh embryo (OR 0.76, 95% CI 0.68-0.86, p < 0.00). In the sub-analysis of 1,154 cycles using slow embryos, there was no statistical difference in LBR (6.40% vs 6.26%, p = 0.92) or CPR (8.10% vs 7.22%, p = 0.58) between the two groups.
Conclusion: This study shows a lower LBR in FET cycles when compared to fresh cycles. Our results suggest that any potential gains in LBR due to improved embryo-endometrial synchrony following FET are lost, presumably due to freeze-thaw process-related embryo damage.
Key words: Fresh, Frozen embryo transfer, Live birth, Embryo, Transfer.
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Chong, Y. S., M. L. H. Chan i S. Liu. "P-143 Comparison of clinical outcomes between overnight warmed and embryo transfer day warmed blastocysts in frozen embryo transfer cycles". Human Reproduction 39, Supplement_1 (1.07.2024). http://dx.doi.org/10.1093/humrep/deae108.516.
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Abstract Study question Is there any difference between clinical outcomes of overnight warmed (ONW) and embryo transfer day warmed (ETDW) blastocysts in frozen embryo transfer (FET) cycles? Summary answer ETDW blastocysts had better clinical outcomes compared to ONW blastocysts in FET cycles. What is known already Some studies reported that the resumption of mitosis in thawed cleavage-stage embryos resulted in significantly better clinical outcomes in FET cycles. Unnecessary transfer of non-functioning embryos can be avoided by incubating thawed embryos overnight to deselect embryos that developed abnormally or failed to undergo additional cleavage. The synchronisation between a viable embryo and a receptive endometrium is vital for successful implantation to take place. The optimal implantation rates occur with embryo-endometrial developmental asynchrony of ± 1.5 days or less. The implantation rates are progressively reduced when embryo-endometrial development asynchrony is greater than 3 days. Study design, size, duration This was a retrospective study involving 2368 FET cycles in KKIVF Centre, KK Women’s and Children’s Hospital, Singapore from Jan 2021 to Dec 2022. The transfer of embryos or blastocysts derived from thawed oocytes, cleavage-stage embryos, double blastocysts and cultured blastocysts from thawed cleavage-stage embryos were excluded. Only single vitrified-warmed blastocyst transfers (n = 1445) were included in this study. Participants/materials, setting, methods Cryopreserved blastocysts were routinely warmed one day before embryo transfer (ET) using Vit Kit - Warm (FUJIFILM Irvine Scientific®) and incubated overnight (ONW group). However, when ETs fell on Monday or post public holiday, vitrified blastocysts were warmed on ET day (ETDW group). Regardless of blastocyst age, surviving blastocysts were transferred into day 5 endometrium. Statistical analysis was performed using t-test or Chi-square test. Differences with P < 0.05 were considered as significant. Main results and the role of chance No statistical significant difference was observed in terms of maternal age distribution at the time of oocyte retrieval between ONW and ETDW groups (34.26 ± 3.29 vs. 34.49 ± 3.22, P = 0.221). Overall, clinical pregnancy rates (CPR) and live birth rates (LBR) were significantly higher in the ETDW group (CPR: 47.47% vs. 40.47%, P < 0.01; LBR: 34.99% vs. 28.78%, P < 0.05). Clinical outcomes were comparable in both ONW and ETDW groups for vitrified-warmed day 5 blastocyst transfers (CPR: 51.27% vs. 58.44%, P = 0.11; LBR: 37.06% vs. 44.81%, P = 0.07). CPR (45.02% vs. 25.71%, P < 0.0001) and LBR (32.03% vs. 17.45%, P < 0.0001) were significantly increased when vitrified day 6 blastocysts were warmed and transferred on the actual day of ET. 18.42% CPR and 13.16% LBR were achieved when vitrified-warmed day 7 blastocysts were transferred on the ET day itself. However, transfer of vitrified-warmed day 7 blastocysts in the ONW group did not result in any pregnancy. Limitations, reasons for caution Study subjects were not stratified according to patient’s age band and blastocyst quality. Age itself is an independent determinant of blastocyst quality which can affect clinical outcomes. Wider implications of the findings Warming of a vitrified blastocyst on ET day is preferred regardless of blastocyst age. However, to facilitate seamless operation in laboratory, overnight warming for vitrified day 5 blastocysts is feasible without compromising clinical outcomes. Trial registration number Not applicable
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Kieu, Violet, Alex Polyakov, Genia Rozen, Daniel Lantsberg, Catharyn Stern i Wan Tinn Teh. "Live birth rates in day 5 fresh versus vitrified single blastocyst transfer cycles: A cross-sectional analysis". International Journal of Reproductive BioMedicine (IJRM), 11.04.2023. http://dx.doi.org/10.18502/ijrm.v21i3.13200.
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Background: The use of frozen embryo transfers (FET) in assisted reproduction has increased worldwide. Controlled ovarian hyperstimulation in a fresh transfer may impair endometrial-embryo synchronicity. However, there is conflicting evidence on live birth rates (LBR) and clinical pregnancy rates (CPR).
Objective: To compare LBRs and CPRs between single autologous day 5 fresh vs. vitrified blastocyst transfer cycles, to investigate the impact of controlled ovarian hyperstimulation on embryo-endometrium asynchrony.
Materials and Methods: A large cross-sectional analysis of 6002 embryo transfers (ET) comprised 3774 fresh and 2228 FET cycles from 2016 to 2019. Multivariate and subgroup analysis were performed for high responders (> 20 oocytes).
Results: Univariate analysis showed no difference in LBR (28.3% vs. 27.4%, p = 0.43) and CPR (32.2% vs. 30.9%, p = 0.30); however, multivariate analysis demonstrated significantly lower LBR (OR 0.864, p = 0.046, 95% CI 0.749-0.997) and CPR (OR 0.852, p = 0.024, 95% CI 0.742-0.979) in FET compared to fresh ETs. Younger participant age, previous in vitro fertilization pregnancy, advanced blastocyst expansion, higher trophectoderm quality, and lower cumulative number of ETs all improved the odds of LBR and CPR. Conventional in vitro fertilization, rather than intracytoplasmic sperm injection, improved CPR but not LBR. Body mass index affected neither LBR nor CPR. In the subgroup, multivariate analysis of high responders showed no difference in LBR or CPR.
Conclusion: This study demonstrates relatively higher LBR and CPR of nearly 14% for fresh ETs compared to FETs, in multivariate analysis. A universal freeze-all strategy, without appropriate indication, may lead to suboptimal outcomes. In high responders, freeze-all cycles may be beneficial, as outcomes appear similar.
Key words: Blastocyst, Live birth, In vitro techniques, Pregnancy rate, Vitrification, Reproduction.
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Vega, A. Gosálvez, M. Rodriguez Mazaira, N. Martin Fernandez, M. Iglesias Nuñez, M. Brandt, L. Vidal Juan, P. Pastor Vargas i in. "O-199 Proof of concept: implantation window must be wider than proposed. Report of seven twins after asynchronous double embryo transfer". Human Reproduction 36, Supplement_1 (1.07.2021). http://dx.doi.org/10.1093/humrep/deab128.010.
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Abstract Study question Can simultaneous transfer of two embryos that were cryopreserved at different stages (D3 and Blastocyst) be appropriate to enhance success in women with more than three failed embryo transfers? Summary answer Double asynchronous embryo transfer offered excellent results in RIF. Unexpectedly high twin rate suggests that embryo-endometrium synchrony is overemphasized. Implantation window must be wider. What is known already Transcriptomic signature of the endometrium has been investigated in the last few years trying to understand the best moment for embryo implantation. Nevertheless, the optimal period has not been well established yet in humans. Simultaneous transfer of two human embryos at different developmental stages (D3 and Blastocyst) on Day 4 was proposed to help couples who have had RIF. Study design, size, duration Observational case-control study. From April 2016 to January 2021, we offered double asynchronous embryo transfer only after Recurrent Implantation Failure (RIF). Two requirements were necessary: 1) Double embryo transfer was acceptable by the couple due to poor reproductive outcome. 2) Availability of two embryos cryopreserved at different stage (D3 and Blastocyst). Results were compared with good prognosis patients (all patients under 35 years in that period who had elected to transfer two day 3 cryopreserved embryos). Participants/materials, setting, methods Forty-five patients accepted to participate in the study. Results were compared with all patients (237) under 35 years where two D3 thawed embryos were transferred. All cases received same protocol (oral estradiol 6mg/d or vaginal estradiol 4mg/d until ultrasound showed endometrial growth) LH, P4 and E2 were monitored in all patients to detect spontaneous LH surge. All cases received transvaginal micronized progesterone 800 mg/d. Embryo transfers were ultrasound guided and Wallace Embryosure catheter was employed. Main results and the role of chance Limitations, reasons for caution Multiple pregnancy rate was unacceptably high. Therefore, it should not be suggested for good prognosis couples where single embryo transfer is clearly advidsed. Our main limitation was the combination of D3 embryos with blastocysts. The retrospective design make the results to be considered as a proof of concept. Wider implications of the findings Double asynchronic embryo transfer can offer new insights in the understanding of human implantation. The concept of implantation window is clearly challenged. Aiming to the center of the window is fine, but we still dońt know how wide is that center. Trial registration number not applicable