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71.
Solar-driven interfacial evaporation has emerged as an innovative and sustainable technology for efficient, clean water production. Real-world applications depend on new classes of low-cost, lightweight, and robust materials that can be integrated into one monolithic device, which withstands a variety of realistic conditions on open water. Self-repairing building blocks are highly desired to prevent permanent failures, recover original functions and maintain the lifetime of interfacial steam generators, although related studies are scarce to date. For the first time, a monolithic, durable, and self-floating interfacial steam generator with well-defined structures is demonstrated by integrating self-healing hydrogels through facile processes in surface modulation and device fabrication. High and stable water evaporation rates over 2.0 kg m−2 h−1 are attained under 1 sun on both fresh water and brine with a broad range of salinity (36–210 g kg−1). The solar evaporation and desalination performance are among the best-performing interfacial steam generators and surpass a majority of devices that are constructed by composite polymers as structural components. This study provides a perspective and highlights the future opportunities in self-healing and damage-tolerant materials that can simultaneously improve the performance, durability, and lifetime of interfacial steam generators in real-world applications.  相似文献   
72.
Traditional self-report measures of psychopathology may be influenced by a variety of recall biases. Ecological momentary assessment (EMA) reduces these biases by assessing individuals’ experiences as they occur in their natural environments. This study examines the discrepancy between trait questionnaire, retrospective report, and EMA measures of affective instability in psychiatric outpatients either with a borderline personality diagnosis (n = 58) or with a current episode of major depressive disorder or dysthymia (n = 42). The authors examined the agreement of 3 trait measures of affective instability—the Affective Instability subscale of the Personality Assessment Inventory–Borderline Features scale (L. C. Morey, 1991), the Affect Intensity Measure (R. J. Larsen, E. Diener, & R. Emmons, 1986), and the Affect Lability Scales (P. D. Harvey, B. R. Greenberg, & M. R. Serper, 1989)—and 1 retrospective mood recall task with EMA indices of mood and mood instability. Results indicate only modest to moderate agreement between momentary and questionnaire assessments of trait affective instability; agreement between recalled mood changes and EMA indices was poor. Implications for clinical research and practice and possible applications of EMA methodology are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
73.
Using the elaborated intrusion theory of desire as a theoretical basis, the present experiments investigated whether mutual competition between modality-specific tasks and desire-related imagery can suppress cravings for caffeine--in particular, coffee. Data from a pilot survey (Experiment 1) in 106 female undergraduate habitual coffee drinkers showed that coffee cravings are characterized predominantly by sensory images in the visual, olfactory, and gustatory modalities. Experiments 2 and 3 tested the prediction that a competing visual or olfactory imagery task would reduce such cravings, relative to an auditory imagery task. In each experiment, 90 female undergraduate habitual coffee drinkers were asked to forego their morning cup of coffee and were subsequently exposed to pictures of coffee (Experiment 2) or actual coffee (Experiment 3). After the craving induction protocol, participants completed either a visual, auditory, or olfactory imagery task with neutral (i.e., non-coffee-related) content. As predicted, the visual and olfactory imagery tasks reduced participants' cravings for coffee, whereas the auditory task did not. Imagery techniques in the visual or olfactory domain could provide a useful adjunct to the behavioral regime of caffeine fading for consumers who are trying to quit caffeine use or reduce their intake. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
74.
75.
Bone defects affect patients functionally and psychologically and can decrease quality of life. To resolve these problems, a simple and efficient method of bone regeneration is required. Human dental pulp stem cells (DPSCs) have high proliferative ability and multilineage differentiation potential. In our previous study, we reported a highly efficient method to induce osteogenic differentiation using DPSC sheets treated with a helioxanthin derivative (4-(4-methoxyphenyl)pyrido[40,30:4,5]thieno[2,3-b]pyridine-2-carboxamide (TH)) in a mouse calvarial defect model. However, the localization of the DPSCs after transplantation remains unknown. Therefore, in this study, we investigated the localization of transplanted DPSCs in a mouse fracture model. DPSCs were collected from six healthy patients aged 18–29 years, cultured in normal medium (NM), osteogenic medium (OM), or OM with TH, and fabricated them into cell sheets. To evaluate the efficacy of fracture healing using DPSCs treated with OM+TH, and to clarify the localization of the transplanted DPSC sheets in vivo, we transplanted OM+TH-treated DPSC sheets labeled with PKH26 into mouse tibiae fractures. We demonstrated that transplanted OM+TH-treated DPSCs sheets were localized to the fracture site and facilitated bone formation. These results indicated that transplanted OM+TH-treated DPSCs were localized at fracture sites and directly promoted fracture healing.  相似文献   
76.
The evolutionary purpose of a fleshy fruit is to attract seed dispersers and get the seeds dispersed by frugivorous animals. For this reason, fruits should be highly rewarding to these mutualists. However, insect herbivory can alter plant reproductive success e.g. by decreasing fruit yield or affecting the attractiveness of the fruits to mutualistic seed dispersers. Under natural conditions, we tested the effects of experimental larval-defoliation on berry ripening and consumption of a non-cultivated dwarf shrub, the bilberry (Vaccinium myrtillus L.), which produces animal-dispersed berries with high sugar and anthocyanin concentration. Bilberry ramets with high fruit yield were most likely to have their berries foraged, indicating that frugivores made foraging choices based on the abundance of berries. Moreover, the probability for berries being foraged was the lowest for non-defoliated ramets that grew adjacent to larval-defoliated ramets, even though larval-defoliation did not affect the biochemical composition (total concentrations of anthocyanins, sugars and organic acids) or the probability of ripening of berries. We hypothesise that the lower probability for berries being foraged in these ramets may be a consequence of rhizome- or volatile-mediated communication between ramets, resulting in a priming effect of the herbivore defence and lower attractiveness of the non-defoliated ramets.  相似文献   
77.
一、前言长期以来,在轮胎中使用高芳烃抽提油(DAE)作为增塑剂一直是较为理想的选择。高芳烃油具有很多应用方面的优点,譬如与轮胎中所使用橡胶的高度相容性、良好的润湿性能等,价格也相对较低。但是,1994年欧洲的一篇调查报告使人们开始关注高芳烃橡胶增塑剂对环境和健康的负面影响。该调查发现,因为行驶过程中的磨损,轮胎颗粒会散布在道路两旁,渗入地下以及水体环境中,而吸附在橡胶颗粒上的有毒组分,并不像过去认为的那样会永远吸附,而是会逐渐分解成为游离态的化学物质。而增塑剂中的化学组分,尤其是有致癌性多环芳烃的组分,对其所散布…  相似文献   
78.
Impulsive personality is an important predictor of risky driving. Acknowledging their impulsive tendencies may help novice drivers to drive more safely. The aim of this study was to evaluate the efficacy of a novel brief intervention targeting novice drivers’ risky behavior in traffic, taking into account potential moderator effects. Driving school students (n = 1866) were divided into an intervention group and a control group. The intervention consisted of a lecture and group work (1.5 h). Subjects’ traffic offenses and crashes were monitored during the following year using police and traffic insurance fund databases. The groups were similar in their baseline characteristics. The intervention group had half as many speeding violations in the year following the intervention compared with the controls. The proportion of speeders was significantly lower in the intervention group compared with the control group in subgroups of subjects with medium cognitive abilities and low or medium BIS-11 impulsiveness levels. In alpha2A-adrenoceptor gene (ADRA2A) G allele carriers, general traffic risk and speeding decreased in response to the intervention, unlike in subjects with the CC genotype. It is concluded that brief interventions that are integrated into the driving education program and focus on personal psychological risk factors may be effective for improving traffic safety.  相似文献   
79.
We report a new certified world‐record efficiency for thin‐film Cu(In,Ga)Se2‐based photovoltaic sub‐modules of 17.4% (aperture area). The record efficiency of the 16 cm2, monolithically integrated, sub‐module has been independently confirmed by Fraunhofer ISE. The record device is the result of extensive co‐optimization of all processing steps. During the optimization process, strong focus has been put on the scalability of processes to cost‐effective mass production, as reflected, for example, in Cu(In,Ga)Se2 deposition time and substrate temperature. Device manufacturing as well as results of electrical and material characterization is discussed. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
80.
An exoelectrogenic culture was enriched on 1.0 g/L xylose from a compost sample in two-chamber microbial fuel cells (MFCs). Electricity production was optimized by changing mixing type, external resistance, xylose concentration and pH. Furthermore, the changes in microbial communities after each optimization step were monitored with PCR-DGGE. Electricity production was highly dependent on operational conditions that affected power densities (PD), Coulombic efficiencies (CE), substrate degradation, utilization of soluble metabolites for electricity production and stability of MFC performance. The optimum operational conditions for electricity production were without mixing, 100 Ω external resistance, 0.5 g/L xylose and pH 7. With optimized operational conditions PD of 590 mW/m2 and CE of 82% were obtained. Microbial community composition, consisting mainly of Geobacter sulfurreducens, Escherichia coli, Sphaerochaeta sp. TQ1 and Bacteroides species, was mainly affected by MFC configuration, i.e. electrical connections, which likely affected the anode potential.  相似文献   
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