39 research outputs found

    Channel Spectral Separation Narrowing for Spectral Beam Combining by Apodisation of the Reflecting Volume Bragg Grating

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    The sidelobe in diffraction efficiency of reflecting volume Bragg grating (RVBG) limits the wavelength channel spectral separation, which determines the combining power output in spectral beam combining (SBC) systems. A novel SBC system based on the apodised RVBG has been proposed to suppress the sidelobe. Several apodised RVBGs have been compared and the optimal apodised RVBG is obtained by using the chain-matrix approach. Numerical results show that the sidelobe could be suppressed excellently with Blackman apodised RVBG. In the numerical example, the minimal channel spectral separation was 1.0 nm for SBC system based on the RVBG and it decreased to 0.6 nm for the novel SBC system based on the Blackman apodised RVBG when the spectral combining efficiency of both systems achieves the same maximum value.Defence Science Journal, 2011, 61(3), pp.201-205, DOI:http://dx.doi.org/10.14429/dsj.61.52

    Association Between the Ratio of Ovarian Stimulation Duration to Original Follicular Phase Length and In Vitro Fertilization Outcomes: A Novel Index to Optimise Clinical Trigger Time

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    The duration of ovarian stimulation which is largely dependent on the ovarian response to hormonal stimulation may influence in vitro fertilization (IVF) outcomes. Menstrual cycle length is potentially a good indicator of ovarian reserve and can predict ovarian response. Ovarian stimulation and the follicular phase of the menstrual cycle are both processes of follicular development. There is no published research to predict the duration of ovarian stimulation based on the length of the menstrual cycle. Our retrospective cohort study included 6110 women with regular menstrual cycles who underwent their first IVF treatment between January 2015 and October 2020. Cycles were classified according to quartiles of the ratio of ovarian stimulation duration to original follicular phase length (OS/FP). Multivariate generalized linear models were applied to assess the association between OS/FP and IVF outcomes. The odds ratio (OR) or relative risk (RR) was estimated for each quartile with the lowest quartile as the comparison group. OS/FP of 0.67 to 0.77 had more retrieved and mature oocytes (adjusted RR 1.11, 95% confidence interval [CI] 1.07–1.15, p for trend = 0.001; adjusted RR 1.14, 95% CI 1.09–1.19, p for trend = 0.001). OS/FP of 0.67 to 0.77 showed the highest rate of fertilization (adjusted OR 1.11, 95% CI 1.05–1.17, p for trend = 0.001). OS/FP > 0.77 had the lowest rate of high-quality blastocyst formation (adjusted OR 0.81, 95% CI 0.71–0.93, p for trend = 0.01). No apparent association was noted between OS/FP and clinical pregnancy, live birth, or early miscarriage rate. In conclusion, OS/FP has a significant effect on the number of oocytes, fertilization rate, and high-quality blastocyst formation rate. MCL could be used to predict the duration of ovarian stimulation with an OS/FP of 0.67 to 0.77, which provides a new indicator for the individualized clinical optimization of the trigger time

    Suppression of FM-to-AM conversion in third-harmonic generation at the retracing point of a crystal

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    FM-to-AM conversion can cause many negative effects (e.g., reducing of margin against damage to the optics, and etc.) on performances of third-harmonic conversion system. In this letter, the FM-to-AM conversion effect in third-harmonic generation is investigated both at and away from the retracing point of type-II KDP crystal. Obtained results indicate that the FM-to-AM conversion can be suppressed effectively when the crystal works at the retracing point.Comment: 8 pages, 5 figures, 1 tabl

    Theoretical Modeling of Protective Oxide Layer Growth in Non-isothermal Lead Alloy Coolant Systems

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    In advanced nuclear energy systems, lead alloys emerge as strong candidates for transmutation and advanced reactor systems as nuclear coolants and spallation neutron targets. However, it is widely recognized that corrosion of materials caused by lead alloys presents a critical barrier to their industrial use. A few experimental research and development projects have been set up by different groups such as at Los Alamos National Laboratory to study the corrosion phenomena in their test facilities and to develop mitigation techniques and materials. One of the central or main techniques under development is to use active control of oxygen thermodynamic activity (OTA) to provide protective oxide layers. Setting OTA in flowing lead alloys makes corrosion highly dependent upon the oxygen concentration and the oxidation processes at materials surfaces. The active oxygen control technique exploits the fact that lead and bismuth are chemically less active than the major components of steels, such as Fe, Ni, and Cr. By carefully controlling the oxygen concentration in lead-bismuth eutectic (LBE), it is possible to maintain an iron- and chrome based oxide film on the surfaces of structural steels, while keeping lead and bismuth from excessive oxidization that can lead to precipitation contamination. Thermal analysis has given an ideal oxygen level range in a non-isothermal lead alloy coolant system. However, in a practical coolant loop, the proper oxygen level depends not only on thermal factors but also on hydraulic factors (system operating temperature, temperature profile, flow velocity, etc.). In addition, the oxygen distribution in a non-isothermal lead alloy coolant system is still unclear. The optimal oxygen levels still need to be investigated

    Advances in molecular mechanisms of intrauterine adhesions

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    Intrauterine adhesions (IUA) is a refractory disease affecting female reproductive health. With the development of medicine, the etiology of IUA has been further studied. At present, the high risk factors that can lead to IUA include: curettage after pregnancy, post-caesarean section, trophoblastocyte disease curettage, postpartum hemorrhage curettage, diagnostic curettage, hysteroscopic surgery, intrauterine device placement, reproductive tract tuberculosis infection, Müllerian duct malformation, etc. Endometrial fibrosis is a main pathological feature. After various signals stimulate different molecular signaling pathways, various growth factors and cytokines interact with each other in vivo to promote the development of fibrosis, which ultimately lead to the occurrence of IUA. At present the current clinical treatment and prevention of IUA is not ideal, especially for moderate and severe IUA. Therefore, the research of the pathogenesis may support the targeted therapy for IUA. This paper aims to review the recent progress in the etiology and molecular mechanism of IUA

    Platelet-rich plasma improves therapeutic effects of menstrual blood-derived stromal cells in rat model of intrauterine adhesion

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    Abstract Background Intrauterine adhesion (IUA) is a major cause of female secondary infertility. We previously demonstrated that menstrual blood-derived stromal cell (MenSC) transplantation helped severe IUA patients have pregnancy and endometrium regeneration. We also initiated platelet-rich plasma (PRP) acted as a beneficial supplement in MenSC culturing and a potential endometrial receptivity regulator. Here, we investigated the therapeutic effect of combined transplantation of MenSCs with PRP in rat IUA models and the mechanisms of MenSCs in endometrium regeneration. Methods Rat IUA models were established by intrauterine mechanical injured. Nine days later, all rats were randomly assigned to four groups received different treatment: placebo, MenSC transplantation, PRP transplantation, and MenSCs + PRP transplantation. The traces of MenSCs were tracked with GFP label. Endometrial morphology and pathology, tissue proliferation, inflammation, pregnancy outcomes, and mechanism of MenSCs in the regeneration of endometrium were investigated. Results Notably, at days 9 and 18 post-treatment, MenSC transplantation significantly improved endometrial proliferation, angiogenesis, and morphology recovery and decreased collagen fibrosis and inflammation in the uterus. MenSCs had lesion chemotaxis, colonized around the endometrial glands. Gene expression of human-derived secretory protein IGF-1, SDF-1, and TSP-1 was detected in the uterus received MenSCs at day 18. The three treatments can all improve fertility in IUA rats. Moreover, gene expressions of cell proliferation, developmental processes, and other biological processes were induced in MenSC transplantation group. Hippo signaling pathway was the most significantly changed pathway, and the downstream factors CTGF, Wnt5a, and Gdf5 were significantly regulated in treatment groups. PRP enhanced these parameters through a synergistic effect. Conclusions In summary, MenSCs could effectively improve uterine proliferation, markedly accelerate endometrial damage repairment and promote fertility restoration in IUA rats, suggesting a paracrine restorative effect and Hippo signaling pathway stimulation. Our results indicate MenSCs, a valuable source of cells for transplantation in the treatment intrauterine adhesion. Combined with PRP, this cell therapy was more effective

    Sexual and psychological health of couples with azoospermia in the context of the COVID-19 pandemic

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    Background To date, there have been no reports on the sexual and psychological health of patients with azoospermia during the coronavirus disease 2019 (COVID-19) pandemic. Previous studies on the sexual health of couples with azoospermia are limited and are especially lacking in data on the wives of azoospermic men. Methods We conducted a case–control cross-sectional study between 1 July 2020 and 20 December 2020. In total, 100 couples with azoospermia comprised the experimental group and 100 couples with normozoospermia comprised the control group. The couples’ sexual health was measured using standardised sexual function questionnaires (male: International Index of Erectile Function-15 [IIEF-15] and Premature Ejaculation Diagnostic Tool [PEDT]; female: Female Sexual Function Index [FSFI]) and a self-designed questionnaire to evaluate changes in sexual behaviours (sexual satisfaction, desire, frequency of sexual activity, masturbation, and pornography use) during lockdown. The couples’ psychological health was measured using the 7-item Generalized Anxiety Disorder (GAD-7) scale and 9-item Patient Health Questionnaire (PHQ-9). The Actor–Partner Interdependence Model (APIM) was used to analyse the associations between sexual health and psychological health. Results The IIEF-15 scores (53.07 ± 11.11 vs. 57.52 ± 8.57, t =  − 3.17, p = 0.00) were lower and the PEDT scores (6.58 ± 3.13 vs. 5.17 ± 2.22, t = 3.67, p = 0.00) and incidence of premature ejaculation (χ2 = 14.73, p = 0.00) were higher for men with azoospermia than for men with normozoospermia. Compared with those of wives of men with normozoospermia, the total FSFI scores (25.12 ± 5.56 vs. 26.75 ± 4.82, t =  − 2.22, p = 0.03) of wives of men with azoospermia were lower. The chi-square test showed that the perceived changes in sexual satisfaction (χ2 = 7.22, p = 0.03), frequency of masturbation (χ2 = 21.96, p = 0.00), and pornography use (χ2 = 10.90, p = 0.01) were significantly different between the female groups with azoospermia and normozoospermia, but there were no significant changes in sexual behaviour between the male groups. The GAD-7 (men: 7.18 ± 5.56 vs. 5.68 ± 4.58, p = 0.04; women: 6.65 ± 5.06 vs. 5.10 ± 3.29, p = 0.01) and PHQ-9 scores (men: 10.21 ± 6.37 vs. 7.49 ± 6.10, p = 0.00; women: 8.81 ± 6.50 vs. 6.98 ± 4.43, p = 0.02) were significantly higher for couples with azoospermia than for couples with normozoospermia. The APIM showed that for couples with azoospermia, sexual function negatively correlated with their own anxiety (men: β = −0.22, p = 0.00; women: β = −0.38, p = 0.00) and depression symptoms (men: β = −0.21, p = 0.00; women: β = −0.57, p = 0.00) but not with their partner’s anxiety and depression symptoms (p > 0.05). Conclusions Couples with azoospermia had a lower quality of sexual function and higher levels of psychological distress than couples with normozoospermia. Their sexual health negatively correlated with psychological distress

    The Modified Bushen Antai Recipe Upregulates Estrogen and Progesterone Receptors at the Maternal-Fetal Interface in Pregnant Rats with Mifepristone-Induced Pregnancy Loss

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    Background. The modified Bushen Antai recipe (BSAT) is a centuries-old traditional Chinese medicine that we use in our center as a therapy against pregnancy loss. Our study aimed to explore the potential benefit and mechanism of BSAT in pregnant rats with mifepristone-induced pregnancy loss. Materials and Methods. The signature compounds of the eight BSAT ingredients were analyzed by high-performance liquid chromatography (HPLC). The BSAT group (n = 8) was treated daily with 6.3 ml/kg BSAT from gestation day (D) 0.5 to 10.5 and once with 1.25 mg/kg mifepristone on D 10.5. Normal saline replaced BSAT in the model group (n = 8), and both BSAT and mifepristone in the control group (n = 8). Morphological and histological analyses were performed on D 13.5. Results. BSAT contains eight medicinal ingredients including Cuscuta chinensis and Dipsacus asperoides. The HPLC analysis detected the signature compounds of seven medicinal ingredients in the extract. Embryo resorption rate in the BSAT group was significantly lower than that in the model group, although the number of surviving embryos was similar between the two groups. Hematoxylin and eosin (HE) staining suggested that the maximum cross-sectional area of the placenta and the area ratio of the placental labyrinth in the BSAT group were higher than those in the model group. Immunohistochemical (IHC) staining indicated that the expression of ki67, estrogen receptor alpha (ERα), and progesterone receptor (PR) in the placental labyrinth of the BSAT group was higher than that of the model group. Furthermore, the protein levels of ERα, PR, phospho-Akt/Akt, and phospho-Erk1/2/Erk1/2 in the BSAT group were higher than those in the control group. The mRNA levels of ERα and PR in the BSAT group were higher than those in the control group. Conclusions. BSAT may induce estrogen and progesterone receptors by phosphorylation via the classic Akt and Erk1/2 signaling pathways in the maternal-fetal interface of pregnant rats, thereby reducing the pregnancy loss rate and improving the live birth rate
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