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21.
The application of strippable coatings is an innovative technology for decontamination of nuclear plants and for any decontamination project aiming at removing surface contamination. An adhesive plastic coating is applied on the contaminated surface. The strippable coating is allowed to cure for up to 24 h, after which it can be easily peeled. The coating traps the contaminants in the polymer matrix. Strippable coatings are non-toxic and do not contain volatile compounds or heavy metals. Since the coating constitutes a solid waste, disposal is easier than treating contaminated liquid wastes, produced by the baseline technology: steam vacuum cleaning, based upon superheated pressurized water in order to remove contaminants from floors and walls. A life cycle assessment (LCA) has been carried out with the purpose of comparing the strippable coating with the steam vacuum technology. The functional unit of the study is represented by a surface of 1 m2 to be decontaminated. The results of LCA achieved using Sima Pro 5.0® software confirm the good environmental performances of strippable coatings. Taking into account both LCA and environmental costs for liquid wastes, the advantages of strippable coatings will be more and more evident.  相似文献   
22.
Retinitis pigmentosa (RP) is a family of inherited disorders caused by the progressive degeneration of retinal photoreceptors. There is no cure for RP, but recent research advances have provided promising results from many clinical trials. All these therapeutic strategies are focused on preserving existing photoreceptors or substituting light-responsive elements. Vision recovery, however, strongly relies on the anatomical and functional integrity of the visual system beyond photoreceptors. Although the retinal structure and optic pathway are substantially preserved at least in early stages of RP, studies describing the visual cortex status are missing. Using a well-established mouse model of RP, we analyzed the response of visual cortical circuits to the progressive degeneration of photoreceptors. We demonstrated that the visual cortex goes through a transient and previously undescribed alteration in the local excitation/inhibition balance, with a net shift towards increased intracortical inhibition leading to improved filtering and decoding of corrupted visual inputs. These results suggest a compensatory action of the visual cortex that increases the range of residual visual sensitivity in RP.  相似文献   
23.
We conducted a prospective study that tracked the frequency of potentially traumatic events (PTEs) and nontraumatic events among college students over a 4-year period using a weekly web-based survey. At the study's completion, participants attempted to recall the number of events they had endorsed on the web surveys. Although participants underrecalled the frequency of all types of life events, recollection was more accurate for PTEs than for non-PTEs. Recalled-frequency of PTEs was associated positively with distress at recall and inversely with trait self-enhancement. These effects were qualified by a distress × self-enhancement interaction. High distress at recall was associated with a greater recalled-frequency of PTEs, but only for people low in trait self-enhancement. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
24.
A recent article in New York Magazine echoed what psychological studies of parenthood have consistently demonstrated since the 1970s: “Most people assume that having children will make them happier. Yet a wide variety of academic research shows that parents are not happier than their childless peers, and in many cases are less so” (Senior, 2010). There is consistent evidence that, as opposed to other life events that cause transient disruptions in life satisfaction, becoming a parent appears to cause harm to individual subjective well-being (Twenge, Campbell, & Foster, 2003), and that this harm is sustained over time (Clark, Diener, Georgellis, & Lucas, 2008). The current investigation was predicated on the concern that these findings may be the result of the methodology used to examine them. As the experience of parenthood does not represent a unified phenomenon, we employed a methodological approach that allows for the exploration of heterogeneity as well as its predictors. By modeling heterogeneous trajectories within a prospective design from 4 years prior to 4 years after the birth of a parent's first child, we find that the majority of individuals (84.2%) demonstrate no long-term effects on life satisfaction in response to childbirth. Only a small percentage demonstrate the sustained declines (7.2%), and a significant cohort, previously unobserved in the literature, demonstrate dramatic and sustained improvements in response to parenthood (4.3%), providing compelling evidence for heterogeneity in life satisfaction among parents. Key demographic covariates that distinguish between trajectories of response are also explored. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
25.
The release of cholecystokinin-like immunoreactivity (CCK-LI) in human brain was investigated using synaptosomes prepared from neocortical specimens removed during neurosurgery. CCK-LI basal release from superfused synaptosomes was increased 3 to 4-fold during depolarization with 15 mM KCI. The K(+)-evoked overflow of CCK-LI was strictly Ca(++)-dependent. The gamma-aminobutyric acidB (GABA(B)) receptor agonist (-)baclofen (0.3-100 microM) inhibited CCK-LI overflow in a concentration-dependent manner (EC50 = 2.20 microM; maximal effect: 45%). The novel GABA(B) receptor ligand CGP 47656 mimicked (-)baclofen (EC50 = 2.45 microM; maximal effect: 50%), whereas the GABA(A) agonist muscimol was ineffective up to 100 microM. The inhibitory effect of 10 microM (-)baclofen on the CCK-LI overflow was concentration-dependently prevented by two selective GABA(B) receptor antagonists, CGP 35348 (IC50 = 13.91 microM) and CGP 52432 (IC50 = 0.08 microM). The effect of 10 microM CGP 47656 was abolished by 1 microM CGP 52432. In experiments on [3H]GABA release, CGP 47656 behaved as an antagonist at the GABA(B) autoreceptors: added at 10 microM, it prevented the inhibitory effect of 10 microM (-)baclofen on the K+ (15 mM)-evoked release of [3H]GABA from human synaptosomes. We conclude that 1) the release of CCK-LI evoked from human brain tissue appears of neuronal origin; 2) the CCK-releasing terminal possess inhibitory presynaptic GABA(B) receptors; 3) these receptors differ pharmacologically from human neocortex GABA(B) autoreceptors, which are CGP 35348-insensitive (Fassio et al., 1994) but can be blocked by CGP 47656; 4) because cholecystokinin has been implicated in anxiety, the GABA(B) receptors here characterized may represent targets for novel anxiolytic agents.  相似文献   
26.
Design and fabrication of single photon avalanche detector (SPAD) in planar technology is reported. Device design and critical issues in the technology are discussed. Experimental test procedures are described for dark-counting rate, afterpulsing probability, photon timing resolution, and quantum detection efficiency. Low-noise detectors are obtained, with dark counting rates down to 10 c/s for devices with 10 /spl mu/m diameter, down to 1 kc/s for 50 /spl mu/m diameter. The technology is suitable for monolithic integration of SPAD detectors and associated circuits.  相似文献   
27.
The impact of added saffron on the characteristics of yoghurt was evaluated during storage. The fat content was lower in the saffron yoghurt. All colour variables were significantly affected by saffron and storage. From the 15th day of storage, bacterial numbers in the saffron yoghurt were higher than those of the control yoghurt. Sensory analysis data suggested that colour, odour and texture impacted consistently on the overall acceptability of the saffron yoghurt. Saffron addition significantly increased polyphenol content and antioxidant activity, providing evidence that the enrichment of natural yoghurt with saffron yields an innovative fermented product useful for supplementing antioxidant dietary intake.  相似文献   
28.
Motor neuron diseases (MNDs) are neurodegenerative disorders characterized by upper and/or lower MN loss. MNDs include amyotrophic lateral sclerosis (ALS), spinal muscular atrophy (SMA), and spinal and bulbar muscular atrophy (SBMA). Despite variability in onset, progression, and genetics, they share a common skeletal muscle involvement, suggesting that it could be a primary site for MND pathogenesis. Due to the key role of muscle-specific microRNAs (myomiRs) in skeletal muscle development, by real-time PCR we investigated the expression of miR-206, miR-133a, miR-133b, and miR-1, and their target genes, in G93A-SOD1 ALS, Δ7SMA, and KI-SBMA mouse muscle during disease progression. Further, we analyzed their expression in serum of SOD1-mutated ALS, SMA, and SBMA patients, to demonstrate myomiR role as noninvasive biomarkers. Our data showed a dysregulation of myomiRs and their targets, in ALS, SMA, and SBMA mice, revealing a common pathogenic feature associated with muscle impairment. A similar myomiR signature was observed in patients’ sera. In particular, an up-regulation of miR-206 was identified in both mouse muscle and serum of human patients. Our overall findings highlight the role of myomiRs as promising biomarkers in ALS, SMA, and SBMA. Further investigations are needed to explore the potential of myomiRs as therapeutic targets for MND treatment.  相似文献   
29.
Many people are exposed to loss or potentially traumatic events at some point in their lives, and yet they continue to have positive emotional experiences and show only minor and transient disruptions in their ability to function. Unfortunately, because much of psychology's knowledge about how adults cope with loss or trauma has come from individuals who sought treatment or exhibited great distress, loss and trauma theorists have often viewed this type of resilience as either rare or pathological. The author challenges these assumptions by reviewing evidence that resilience represents a distinct trajectory from the process of recovery, that resilience in the face of loss or potential trauma is more common than is often believed, and that there are multiple and sometimes unexpected pathways to resilience. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
30.
The authors examined self-enhancing bias as a predictor of adjustment among individuals in or near the World Trade Center during the September 11, 2001, terrorist attacks. Resilience was defined from categorical and continuous analyses of both participant self-report and friend and relative ratings of adjustment. Self-enhancement was associated with a resilient outcome, ratings of better adjustment prior to September 11th, greater positive affect, and reduced perceptions of social constraints. Additional analyses indicated that self-enhancers' reduced symptom levels were fully mediated by their low perceived social constraints. However, consistent with previous evidence suggesting a social cost to self-enhancement, at 18 months post-September 11th, self-enhancers' friends and relatives also rated them as decreasing in social adjustment and as being less honest. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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