Spin Excitations in BaFe1.84Co0.16As2 Superconductor Observed by Inelastic Neutron Scattering

Superconductivity appears to compete against the spin-density-wave in Fe pnictides. However, optimally cobalt doped samples show a quasi-two-dimensional spin excitation centered at the (0.5, 0.5, L) wavevector, "the spin resonance peak", that is strongly tied to the onset of superconductivity. By inelastic neutron scattering on single crystals we show the similarities and differences of the spin excitations in BaFe1.84Co0.16As2, with respect to the spin excitations in the high-temperature superconducting cuprates. As in the cuprates the resonance occurs as an enhancement to a part of the spin excitation spectrum which extends to higher energy transfer and higher temperature. However, unlike in the cuprates, the resonance peak in this compound is asymmetric in energy.Comment: 12 pages, 6 figures; PACS # 74.70.-b, 74.20.Mn, 78.70.Nx, 74.25.Ha; corrected discussion of figures in tex

High pressure effects in fluorinated HgBa2Ca2Cu3O(8+d)

We have measured the pressure sensitivity of Tc in fluorinated HgBa2Ca2Cu3O(8+d) (Hg-1223) ceramic samples with different F contents, applying pressures up to 30 GPa. We obtained that Tc increases with increasing pressure, reaching different maximum values, depending on the F doping level, and decreases for a further increase of pressure. A new high Tc record (166 K +/- 1 K) was achieved by applying pressure (23 GPa) in a fluorinated Hg-1223 sample near the optimum doping level. Our results show that all our samples are at the optimal doping, and that fluorine incorporation decreases the crystallographic $a$-parameter concomitantly increasing the maximum attainable Tc. This effect reveals that the compression of the $a$ axes is one of the keys that controls the Tc of high temperature superconductors.Comment: 4 pages, 4 figures, submitted to Phys. Rev.

Synthesis of Single Phase Hg-1223 High Tc Superconducting Films With Multistep Electrolytic Process

We report the multistep electrolytic process for the synthesis of high Tc single phase HgBa2Ca2Cu3O8+ (Hg-1223) superconducting films. The process includes : i) deposition of BaCaCu precursor alloy, ii) oxidation of BaCaCu films, iii) electrolytic intercalation of Hg in precursor BaCaCuO films and iv) electrochemical oxidation and annealing of Hg-intercalated BaCaCuO films to convert into Hg1Ba2Ca2Cu3O8+ (Hg-1223). Films were characterized by thermo-gravimetric analysis (TGA) and differential thermal analysis (DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The electrolytic intercalation of Hg in BaCaCuO precursor is proved to be a novel alternative to high temperature-high pressure mercuration process. The films are single phase Hg-1223 with Tc = 121.5 K and Jc = 4.3 x 104 A/cm2.Comment: 17 Pages, 10 Figures. Submitted to Superconductor Science and Technolog

Outcomes in poor responders treated with in vitro fertilization/intracytoplasmic sperm injection according to bologna criteria

Purpose of the study was to evaluate the effectiveness of various approaches of artificial reproductive technologies (ART) in advanced maternal age patients with poor ovarian response (POR). Materials and methods. This is retrospective cohort study of 455 patients with POR who have undergone an IVF and embryo transfer program at from June 2016 to June 2018. Researchers evaluated pregnancy rate (PR) per embryo transferand live birth rate (LBR) per embryo transferas in vitro fertilization (IVF) outcomes. The patients fulfilled Bologna criteria were divided into 5 groups: long protocol, ant-gonadotropin-releasing hormone protocol, freeze embryos transfer without preimplantation genetic diagnostic (PGS), freeze embryos transfer with PGS, natural cycle. Results. There was no statistically significant difference in the age, Anti-Müllerian hormone level and duration of infertility between the groups. Despite different protocols of ovarian stimulation, there was no statistically significant difference in pregnancy rate in fresh cycles. At the same time, cancellation of transfer was significantly higher observed in natural cycles (p <0.001). PR and LBR were statistically significant higher in freeze embryo transfer group 29% and 12.1% vs 13.3% and 5,5% respectively (p<0.001 and p = 0.040). During the transfer of the embryo unexamined by PGS and after PGS the pregnancy rate did not differ (29.4% vs 28.2%, p <0.05), but LBR was statistically significant higher after euploid embryo transfer (8.2% without PGS vs 20.5% after PGS, p = 0.028). Conclusion. The most effective approach in patients with a poor ovarian response was cycle segmentation, cryopreservation of embryos, PGS and transfer of an euploid embryo. This category of patients requires a personalized approach to the treatment of infertility. The choice of protocol in ART program must be carried out with the full voluntary and informed consent of the patient, depending on their desires and capabilities, including financial

The Impacts of Infrastructure in Development: A Selective Survey

Development economists have considered physical infrastructure to be a precondition for industrialization and economic development. Yet, two issues remain to be addressed in the literature. First, while proper identification of the causal effectiveness of infrastructure in reducing poverty is important, experimental evaluation, such as randomized control trials (RCT)-based evaluation, is difficult in the context of large-scale infrastructure. Second, while micro studies so far have focused on the nexus between infrastructure and certain types of poverty outcomes such as income, poverty, health, education, and other individual socio-economic outcomes, to better interpret a wide variety of micro-level infrastructure evaluation results using either experimental or non-experimental methods, the role of infrastructure should be placed in a broader context. To bridge these gaps, we augment the existing review articles on the same topic, such as Estache (2010), Hansen, Andersen, and White, (2012), and World Bank (2012) by addressing these two remaining issues. First, while forming a counterfactual is often difficult for impact evaluation of infrastructure, engineering constraints beyond human manipulation can allow people to adopt quasi-experimental methods of impact evaluation. Second, evaluators can adopt, for example, a hybrid method of natural and artefactual field experiments to elicit the role of infrastructure in facilitating the complementarity of the market, state, and community mechanisms

Evaluation of midkine and anterior gradient 2 in a multimarker panel for the detection of ovarian cancer

The aims of this study were: to characterise and compare plasma concentrations of midkine (MDK) in normal healthy women with concentrations observed in women with ovarian cancer; and to establish and compare the performance of MDK with that of anterior gradient 2 protein (AGR2) and CA125 in the development of multi-analyte classification algorithms for ovarian cancer. Median plasma concentrations of immunoreactive MDK, AGR2 and CA125 were significantly greater in the case cohort (909 pg/ml, 765 pg/ml and 502 U/ml, respectively n = 46) than in the control cohort (383 pg/ml, 188 pg/ml and 13 U/ml, respectively n = 61) (p < 0.001). The area under the receiver operator characteristic curve (AUC) for MDK and AGR2 was not significantly different (0.734 ± 0.046 and 0.784 ± 0.049, respectively, mean ± SE) but were both significantly less than the AUC for CA125 (0.934 ± 0.030, p < 0.003). When subjected to stochastic gradient boosted logistic regression modelling, the AUC of the multi-analyte panel (MDK, AGR2 and CA125, 0.988 ± 0.010) was significantly greater than that of CA125 alone (0.934 ± 0.030, p = 0.035). The sensitivity and specificity of the multi-analyte algorithm were 95.2 and 97.7%, respectively. Within the study cohort, CA125 displayed a sensitivity and specificity of 87.0 and 94.6%, respectively. The data obtained in this study confirm that both MDK and AGR2 individually display utility as biomarkers for ovarian cancer and that in a multi-analyte panel significantly improve the diagnostic utility of CA125 in symptomatic women

Phase II biomarker trial of a multimarker diagnostic for ovarian cancer

The primary hypothesis to be tested in this study was that the diagnostic performance (as assessed by the area under the receiver operator characteristic curve, AUC) of a multianalyte panel to correctly identify women with ovarian cancer was significantly greater than that for CA-125 alone