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Stimulated recall methods were used to assist 34 group leaders in recalling their intentions (i.e., purposes, plans, goals) in relation to interventions they made in a group session. A total of 835 intentions were reported by the leaders and were categorized into 6 separate intention categories by trained judges. The categories included directing the group, gathering information and assessing members, challenging members, attending to and validating members' experiences, directing self, and promoting connections and interactions among group members. Multidimensional scaling procedures revealed 4 intention clusters: Promoting Insight/Change, Planning and Guiding, Attending, and Assessing Growth. Limitations of the study are addressed, along with implications for future research and group leader training. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This paper compares the position and performance of Africans in international research networks, comparing a well-funded and internationally driven research network against a network developing organically with less funding and oversight. Specifically, we map the co-authorship networks related to African governance and public policy (1) in general and (2) related to HIV/AIDS. In both research networks Africans are well positioned globally, but African authors have lower connectivity and status in the HIV/AIDS network than the general network. Links between authors in different African countries are often bridged by non-Africans. This makes the African research networks vulnerable to shifting funding priorities; and international dropout would fragment the HIV/AIDS network more than the general network. We conclude that funders and researchers should prioritize direct inter-country African collaborations to improve the resilience of African research networks.  相似文献   
15.
The genus Aeromonas is one of several medically significant genera that have gained prominence due to their evolving taxonomy and controversial role in human diseases. In this study, matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) was used to analyze the whole cells of both reference strains and unknown Aeromonas isolates obtained from water distribution systems. A library of over 45 unique m/z signatures was created from 40 strains that are representative of the 17 recognized species of Aeromonas, as well as 3 reference strains from genus Vibrio and 2 reference strains from Plesiomonas shigelloides. The library was used to help speciate 52 isolates of Aeromonas. The environmental isolates were broken up into 2 blind studies. Group 1 contained isolates that had a recognizable phenotypic profile and group 2 contained isolates that had an atypical phenotypic profile. MALDI-MS analysis of the water isolates in group 1 matched the phenotypic identification in all cases. In group 2, the MALDI-MS-based determination confirmed the identity of 18 of the 27 isolates. These results demonstrate that MALDI-MS analysis can rapidly and accurately classify species of the genus Aeromonas, making it a powerful tool especially suited for environmental monitoring and detection of microbial hazards in drinking water.  相似文献   
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Phenolic compounds are the most important antioxidants of virgin olive oil. This paper reports on the application of solid phase extraction (SPE) in the separation of phenolic compounds from olive fruit, olive oil, and by-products of the mechanical extraction of the oil and the complete spectroscopic characterization by nuclear magnetic resonance of demethyloleuropein and verbascoside extracted from olive fruit. SPE led to a higher recovery of phenolic compounds from olives than did liquid/liquid extraction. SPE also was used to separate phenolic compounds from pomaces and vegetation waters. Phenylacid and phenyl-alcohol concentrations in extracts obtained from SPE and liquid/liquid extraction were not significantly different (P<0.05). The recovery of the dialdehydic form of elenolic acid linked to 3,4-(dihydroxyphenyl)ethanol and an isomer of oleuropein aglycon, however, was low.  相似文献   
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以十二烷基磺酸钠为例,考察了利用电位滴定方法分析ASP三元复合驱采出液中表面活性剂浓度时,pH值、盐度、聚合物含量、石油酸皂浓度等因素对分析结果的影响,研究出因石油酸皂和聚合物的存在导致结果偏高的消除方法,并对方法的检出限进行研究。该方法为ASP三元驱中十二烷基磺酸钠类阴离子表面活性剂浓度的分析提供了参考。  相似文献   
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Abstract: Antioxidant activity (AA) of quinoa (Chenopodium quinoa Willd.) seeds, as well as of durum wheat (Triticum turgidum L. ssp. durum Desf.) and of emmer (T. turgidum L. ssp. dicoccum Schübler) grains, was evaluated by studying hydrophilic (H), lipophilic (L), free‐soluble (FSP) and insoluble‐bound (IBP) phenolic extracts using the new lipoxygenase/4‐nitroso‐N,N‐dimethylaniline (LOX/RNO) method, able to simultaneously detect different antioxidant mechanisms, as well as using the Oxygen Radical Absorbance Capacity (ORAC) and the Trolox Equivalent Antioxidant Capacity (TEAC) assays, which measure the scavenging activity against peroxyl and ABTS [2,2′‐azino‐bis‐(3‐ethylbenzothiazoline‐6‐sulfonate)] radicals, respectively. The species under study were compared with respect to the sum of AA values of H, L and FSP extracts (AAH+L+FSP), containing freely solvent‐soluble antioxidants, and AA values of IBP extracts (AAIBP), representing the phenolic fraction ester‐linked to insoluble cell wall polymers. The LOX/RNO and ORAC methods measured in quinoa flour a remarkable AAH+L+FSP higher than durum wheat, although lower than emmer; according to the same assays, the IBP component of quinoa resulted less active than the durum wheat and emmer ones. The TEAC protocol also revealed a high AAH+L+FSP for quinoa. Interestingly, the ratio AAH+L+FSP/AAH+L+FSP+IBP, as evaluated by the LOX/RNO and ORAC assays, resulted in quinoa higher than that of both durum wheat and emmer, and much higher than durum wheat, according to the TEAC protocol. This may suggest that antioxidants from quinoa seeds may be more readily accessible with respect to that of both the examined wheat species. Practical Applications: Quinoa seeds may represent an excellent source of natural antioxidant compounds and, in particular, of the free‐soluble antioxidant fraction. These compounds may improve nutritive and health‐beneficial properties of quinoa‐based gluten‐free products, thus expanding interest for quinoa utilization from celiac patients to the general population.  相似文献   
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Biocompatibility is of paramount importance for drug delivery, tumor labeling, and in vivo application of nanoscale bioprobes. Until now, biocompatible surface processing has typically relied on PEGylation and other surface coatings, which, however, cannot minimize clearance by macrophages or the renal system but may also increase the risk of chemical side effects. Cell membranes provide a generic and far more natural approach to the challenges of encapsulation and delivery in vivo. Here we harness for the first time living cells as "factories" to manufacture cell membrane capsules for encapsulation and delivery of drugs, nanoparticles, and other biolabels. Furthermore, we demonstrate that the built-in protein channels of the new capsules can be utilized for controlled release of encapsulated reagents.  相似文献   
20.
In the conceptual design stage, outcomes of industrial designers work are generally represented by set of sketches where curves, notes, shadows, and colors implicitly represent creative ideas. Signs and annotations are used to synthesize and concretize the design intent that, finally, will be transformed into the styling product visual appearance. The loss of the original design intent may be due to the complexity of the design process, and the involvement of different actors. Our aim is to provide a method and relative tools in order to interpret signs on sketches for eliciting the design intent. The analysis result is a set of aesthetic features that can be used for driving CAD modeling, in the case both of Reverse Engineering applications and of product modeling for restyling purposes. Sketches analysis is based on a semiotic interpretation driven by the formalization of the cognitive models used in the conceptual design phase. The approach showed promising results on different styling products test cases.  相似文献   
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