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81.
The fabrication and characterization of a nanoscale resonant optical filter at wavelength around 850 nm is reported using standard C-MOS compatible microelectronics techniques. We discuss the different steps of the process and their impact on the final structure. We show that the use of these techniques gives an efficient filter on glass substrate with high transmission and a narrow bandwidth of 0.4 nm. We also demonstrate the same process on a silicon substrate for a potential integration with electronic functions.  相似文献   
82.
Influenza is a respiratory virus that alone or in combination with secondary bacterial pathogens can contribute to the development of acute pneumonia in persons >65 years of age. Host innate immune antiviral signaling early in response to influenza is essential to inhibit early viral replication and guide the initiation of adaptive immune responses. Using young adult (3 months) and aged adult mice infected with mouse adapted H1N1 or H3N2, the results of our study illustrate dysregulated and/or diminished activation of key signaling pathways in aged lung contribute to increased lung inflammation and morbidity. Specifically, within the first seven days of infection, there were significant changes in genes associated with TLR and RIG-I signaling detected in aged murine lung in response to H1N1 or H3N2. Taken together, the results of our study expand our current understanding of age-associated changes in antiviral signaling in the lung.  相似文献   
83.
Until recently residual stresses have been included in structural integrity assessments of nuclear pressure vessels and piping in a very primitive manner due to the lack of reliable residual stress measurement or prediction tools. This situation is changing the capabilities of newly emerging destructive (i.e. the contour method) and non-destructive (i.e. magnetic and high-energy synchrotron X-ray strain mapping) residual stress measurement techniques for evaluating ferritic and austenitic pressure vessel components are contrasted against more well-established methods. These new approaches offer the potential for obtaining area maps of residual stress or strain in welded plants, mock-up components or generic test-pieces. The mapped field may be used directly in structural integrity calculations, or indirectly to validate finite element process/structural models on which safety cases for pressurised nuclear systems are founded. These measurement methods are complementary in terms of application to actual plant, cost effectiveness and measurements in thick sections. In each case an exemplar case study is used to illustrate the method and to highlight its particular capabilities.  相似文献   
84.
This report presents the preliminary validation of a French version of the Sexual Activities and Attitudes Questionnaire (SAAQ; Noll, Trickett, & Putnam, 2003), shortened and adapted for romantically involved adults. Findings indicate that the 4-factor structure of the original instrument is replicated in the present sample (N = 335) and that the internal consistency of the factors is high (α between .77 and .85). Correlation analyses highlight the relationship between sexual attitudes, sexual behaviors and couple satisfaction. The preliminary validation of the SAAQ is a first step toward the elaboration of a French multidimensional measure of sexual attitudes for adult couples. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
85.
Participants are usually able to search rapid serial visual presentation (RSVP) streams and report a single target, given that RSVP distractors do not typically deplete attention required for target identification. Here, participants performed single target search, but the target was preceded by a to-be-ignored distractor varying in valence and arousal. When the critical distractor was a sexual word, lower target accuracy was observed, particularly at short distractor-target stimulus onset asynchronies, even when participants were shown the critical distractors beforehand and told to ignore them. No reduction in target accuracy was evidenced when the critical distractor was negative, positive, threatening, or emotionally neutral. Target accuracy was predicted by participants' arousal ratings to the critical distractor words and by their memory for them, but not by their valence ratings. Memory for critical distractors mediated the relationship between arousal and target accuracy. The results provide evidence that arousing sexual words involuntarily capture attention and enter awareness at the expense of goal-driven targets, at least in the context of laboratory experiments performed by young university participants for whom sexual material might have high impact and relevance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
86.
The real-time application of acoustic radiation force impulse (ARFI) imaging requires both short acquisition times for a single ARFI image and repeated acquisition of these frames. Due to the high energy of pulses required to generate appreciable radiation force, however, repeated acquisitions could result in substantial transducer face and tissue heating. We describe and evaluate several novel beam sequencing schemes which, along with parallel-receive acquisition, are designed to reduce acquisition time and heating. These techniques reduce the total number of radiation force impulses needed to generate an image and minimize the time between successive impulses. We present qualitative and quantitative analyses of the trade-offs in image quality resulting from the acquisition schemes. Results indicate that these techniques yield a significant improvement in frame rate with only moderate decreases in image quality. Tissue and transducer face heating resulting from these schemes is assessed through finite element method modeling and thermocouple measurements. Results indicate that heating issues can be mitigated by employing ARFI acquisition sequences that utilize the highest track-to-excitation ratio possible.  相似文献   
87.
Studied social interactions of children with each member of their maritally disrupted family, and the contribution of family support variables to children's adjustment. 113 normal 1st–5th graders and 62 from maritally disrupted families (average of 1.2 yrs since parental separation) were interviewed twice, 1 yr apart. An ANOVA and a series of multivariate analyses of variance were performed. An adaptation of the Children's Inventory of Social Support (N. I. Sandler et al, 1984), the Child Behavior Checklist and the Self-Esteem Questionnaire were used. (English abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
88.
Describes a series of studies on the psychometric properties of the French-Canadian adaptation of the latest version (Form Y) of the State–Trait Anxiety Inventory (STAI—Y) by C. D. Spielberger (1983). Results from several samples involving a total of 1,226 male and female Canadian university students (aged 19–55 yrs) reveal that the construct validity and reliability of the French adaptation of the STAI—Y are similar to those of the original English instrument. Norms and T-scores are presented for both scales. (English abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
89.
Recent evidence suggests that TCR down-regulation directly reflects the number of TCRs that have engaged MHC/peptide ligand complexes. Here, we examined the influence of defined peptides on thymic selection based on their ability to induce differential TCR internalization. Our results demonstrate that there is a direct correlation: peptides that induce strong TCR down-regulation are most efficient at mediating negative selection, whereas peptides that induce suboptimal TCR internalization are more efficient at triggering positive selection. As a consequence of suboptimal TCR internalization, a proportion of TCR complexes that remain on the cell surface may be able to relay continual signals required for survival and differentiation. In addition, we show that the magnitude of Ca2+ influx set by these peptides reflects the hierarchy of TCR down-regulation and correlates with positive vs negative selection of transgenic thymocytes. Together, our data suggest that T cell selection is mediated by differing intensities of the same TCR-mediated signal, rather than by distinct signals.  相似文献   
90.
To assess in a pilot study the ability of a single injection of a GnRH antagonist (Cetrorelix) to prevent premature luteinizing hormone (LH) surges in an in-vitro fertilization (IVF) embryo transfer programme when administered on a fixed day in the late follicular phase, ovarian stimulation was carried out in 11 women with two ampoules of human menopausal gonadotrophin per day beginning on day 2 of the menstrual cycle. A 3 mg dose of Cetrorelix was administered on day 8 of the stimulation cycle. A second injection was administered 72 h later if ovulation was not triggered in the meantime. We did not observe a premature LH surge in any of the cycles studied. The injection of 3 mg Cetrorelix was capable of preventing LH surge in all the patients studied, introducing a very simple treatment protocol. Among the patients who received two injections (n = 3), the day of the first administration was delayed in two subjects due to slow follicular maturation kinetics. Out of 11 patients, 10 had an embryo transfer. Four clinical pregnancies were obtained (40% per embryo transfer), of which 3 are ongoing (30% per embryo transfer). A simple administration protocol for a new GnRH antagonist (Cetrorelix) was able to prevent LH surges in the 11 patients studied.  相似文献   
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