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The aim of this research was to determine the levels of human leukocyte antigen G (HLA-G) and endometrial Natural Killer ((e)NK) cell percentages in uterine flushing samples from primary and secondary infertile women. sHLA-G levels were lower in the uterine flushing samples from primary infertile women in comparison with women with secondary infertility. Lower CD56+KIR2DL4+ (e)NK cell percentages were detected in primary infertile women compared with secondary infertile women. This is the first study demonstrating that primary and secondary unexplained infertilities are characterized by different basal sHLA-G levels and CD56+KIR2DL4+ (e)NK cell percentages.  相似文献   
344.
High-pressure torsion (HPT), a severe plastic deformation technique, can effectively improve the thermoelectric performance of skutterudites, resulting in ZT values higher than for ball-milled and hot-pressed (BMHP) samples. In this paper the influence of the HPT parameters, i.e. the number of revolutions (equivalent to the applied strain), the processing temperature and the hydrostatic pressure on the microstructural and thermoelectric properties of the skutterudite DD0.60Fe3CoSb12 are evaluated and compared with the BMHP samples before HPT processing. Whilst the three parameters have specific effects on (i) the crystallite size, (ii) the density of lattice defects and (ii) the density of cracks, a suitable combination thereof allows for an increase of the figure of merit by at least 20%.  相似文献   
345.
Presence describes the feeling of reality and immersion that users of virtual/Internet environments have. Importantly, it has been suggested that there are individual and contextual differences regarding susceptibility to presence. These aspects of presence have been linked to both beneficial and disadvantageous uses of the Internet, such as online therapeutic applications and addictive Internet behaviours. In the present study, presence was studied in relation to individual anxiety symptoms and classroom-level openness to experience (OTE) using a normative sample of 648 adolescents aged between 16 and 18 years. Presence was assessed with the Presence II questionnaire, anxiety symptoms with the relevant subscales of the SCL-90-R, and OTE with the Five-Factor Questionnaire. A three-level hierarchical linear model was calculated. Results showed that experiencing presence in virtual environments dropped between the ages of 16 and 18 years. Additionally, although anxiety symptoms were associated with higher presence at 16 years, this association decreased with age. Results also demonstrated that adolescents in classrooms higher on OTE reported reduced level of experiencing presence. The practical and theoretical implications of these findings are discussed.  相似文献   
346.
The results of microstructural characterization of mortars containing fly ash class C (High Calcium Fly Ash) from combustion of lignite are presented. The evaluation of the microstructure was performed using scanning electron microscope, optical, and confocal microscope. The tested beams were bent till the crack and microcracks opening, which were healed during the different curing time. The results showed that the replacement of cement with fly ash class C influenced the process of crack healing. The addition of HCFA, at both 30% and 60%, speeds up the self‐healing process in cracks and particularly in micro‐cracks. In the research, the completely filling up of the cracks by new phases has not been observed, only the beginning of such process has been noticed. Microsc. Res. Tech., 78:22–29, 2015. © 2014 Wiley Periodicals, Inc.  相似文献   
347.
This project is a trial conducted under contract with CO2CRC, Australia of a new CO2 capture technology that can be applied to integrated gasification combined cycle power plants and other industrial gasification facilities. The technology is based on combination of two low temperature processes, namely cryogenic condensation and the formation of hydrates, to remove CO2 from the gas stream. The first stage of this technology is condensation at −55 °C where CO2 concentration is expected to be reduced by up to 75 mol%. Remaining CO2 is captured in the form of solid hydrate at about 1 °C reducing CO2 concentration down to 7 mol% using hydrate promoters. This integrated cryogenic condensation and CO2 hydrate capture technology hold promise for greater reduction of CO2 emissions at lower cost and energy demand. Overall, the process produced gas with a hydrogen content better than 90 mol%. The concentrated CO2 stream was produced with 95-97 mol% purity in liquid form at high pressure and is available for re-use or sequestration. The enhancement of carbon dioxide hydrate formation and separation in the presence of new hydrate promoter is also discussed. A laboratory scale flow system for the continuous production of condensed CO2 and carbon dioxide hydrates is also described and operational details are identified.  相似文献   
348.
This work reports on the use of two innovative techniques in the field of gas sensors for preparing nano-structured materials: sol-gel and supersonic cluster beam deposition. By means of sol-gel, nano-structured In2O3 thin films have been prepared and deposited under different deposition parameters on silicon wafer. In this way the results have shown a good compatibility of the method with silicon technology, then potentially suitable to be used in the fabrication of integrated devices. The second technique has been applied for the preparation of nano-structured TiO2 thin films showing its capability to be used in the fabrication of gas sensor devices, mainly when a good control of the grain dimension is required.  相似文献   
349.
The demand for radiation portal monitor (RPM) systems has increased, and their capabilities are being further scrutinized as they are being applied to the task of detecting nuclear weapons, special nuclear material, and radiation dispersal device materials that could appear at borders. The requirements and constraints on RPM systems deployed at high-volume border crossings are significantly different from those at weapons facilities or steel recycling plants, where RPMs have been historically employed. In this new homeland security application, RPM systems must rapidly detect localized sources of radiation with a very high detection probability and low false-alarm rate, while screening all of the traffic without impeding the flow of commerce. In light of this new Department of Homeland Security application, the capabilities of two popular gamma-ray-detector materials as applied to these needs are re-examined. Both experimental data and computer simulations, together with practical deployment experience, are used to assess currently available polyvinyltoluene and NaI(Tl) gamma-ray detectors for border applications.  相似文献   
350.
A 32-year-old woman with ulcerative colitis had a relapsed of pyoderma gangrenosum during puerperium. Both the pyoderma gangrenosum and ulcerative colitis had been well controlled with oral prednisolone, but ulcerative colitis relapsed in pregnancy, and pyoderma gangrenosum relapsed in the puerperium. The pyoderma gangrenosum responded to methylprednisolone pulse therapy initially, but relapsed when prednisolone was tapered. A second trial of pulse therapy combined with cyclosporine resulted in complete remission of the pyoderma gangrenosum, and no recurrence was recognized after prednisolone was tapered. This is a very rare case of successful treatment with methylprednisolone pulse therapy combined with cyclosporine for pyoderma gangrenosum complicating ulcerative colitis.  相似文献   
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