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1.
Customers are sensitive to the flavour of water. Customers evaluate drinking water based on their expectations, on experiences with their usual drinking water and on experiences with alternative waters. The Philadelphia Water Department provides one example of success in developing a better understanding of customer perceptions and attitudes about tap water taste and odour. Philadelphia found that customers do communicate in ways that water utilities can understand. Water utilities can enhance that communication and collect useful data. In addition, water utilities can characterise their tap water flavour, track it for changes and correlate changes to customer complaints.  相似文献   
2.
The differential effectiveness of group psychotherapy was estimated in a meta-analysis of 111 experimental and quasi-experimental studies published over the past 20 years. A number of client, therapist, group, and methodological variables were examined in an attempt to determine specific as well as generic effectiveness. Three different effect sizes were computed: active versus wait list, active versus alternative treatment, and pre- to posttreatment improvement rates. The active versus wait list overall effect size (0.58) indicated that the average recipient of group treatment is better off than 72% of untreated controls. Improvement was related to group composition, setting, and diagnosis. Findings are discussed within the context of what the authors have learned about group treatment, meta-analytic studies of the extant group literature, and what remains for future research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
Knowledge of the nutrient content of foods is fundamental for virtually all nutrition-related projects, programmes and policies. Low quality compositional data may lead to inappropriate policies and funds spent unnecessarily. Existing food composition tables (FCT) for most West African countries date back to 1960 and 1970 and contain in general few foods and components without documentation. As a result of the recommendations by the Economic Community of West African States (ECOWAS) Nutrition forum and other high level meetings, FAO/INFOODS, WAHO/ECOWAS and Bioversity International developed the West African FCT. It contains 472 foods and 28 components. Emphasis was given to include data on food biodiversity by incorporating cultivars/varieties and underutilized foods. The West African FCT enables users to address diet-related health problems, strengthen local development, enhance trade and promote biodiversity. In addition it contributes to poverty alleviation in both rural and urban areas. The FCT needs to be updated regularly and it is the most recent example of INFOODS for regional food composition activities.  相似文献   
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The present study seeks to establish the validity of the Group Psychotherapy Intervention Rating Scale (GPIRS), an observer-rated measure of the quality of group leader interventions. Concurrent validity was tested by comparing GPIRS results to 2 group gold standard process measures, the Hill Interaction Matrix and the Group Climate Questionnaire. Significant correlations between leader intervention scores and group member perceptions of group climate, as well as verbal interaction scores, were found. In addition, results indicated correlations between interventions aimed to gain balance between confrontation and warmth and member-rated levels of cohesion. Results lend support for the concurrent validity of the GPIRS. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
Dielectric materials with high electric energy density and low loss are of great importance for applications in modern electronics and electrical systems. Strongly dipolar materials have the potential to reach relatively higher dielectric constants than the widely used non-polar or weakly dipolar polymers, as well as a much lower loss than that of nonlinear high K polymer dielectrics or polymer–ceramic composites. To realize the high energy density while maintaining the low dielectric loss, aromatic polythioureas and polyureas with high dipole moments, high dipole densities, tunable molecular structures and dielectric properties were investigated. High energy density (>24 J/cm3), high breakdown strength (>800 MV/m), and high charge–discharge efficiency (>90%) can be achieved in the new polymers. The molecular structure and film surface morphology were also studied; it is of great importance to optimize the fabrication process to make high-quality thin films.  相似文献   
7.
A novel gamma-carboxyglutamate-containing peptide, designated gamma-conotoxin-PnVIIA, is described from the venom of the molluscivorous snail Conus pennaceus. gamma PnVIIA, triggers depolarization and firing of action potential bursts in the caudodorsal neurons of Lymnaea. This effect is due to activation or enhancement of a slow inward cation current that may underly endogenous bursting activity of these neurons. The amino acid sequence of gamma PnVIIA was determined as DCTSWFGRCTVNS gamma CCSNSCDQTYC gamma-LYAFOS (where gamma is gamma-carboxyglutamate, O is trans-4-hydroxyproline), thus gamma PnVIIA belongs to the six cysteine four loop structural family of conotoxins, and is most homologous to the previously described excitatory conotoxin-TxVIIA. Interestingly, TxVIIA did not induce action potentials in Lymnaea caudodorsal neurons. gamma PnVIIA is the prototype of a new class of gamma-conotoxins that will provide tools for the study of voltage-gated pacemaker channels, which underly bursting processes in excitable systems.  相似文献   
8.
The B-domain of recombinant human Factor VIII comprises 909 amino acids and is extensively N- and O-glycosylated, in that at least 20 different sites are occupied by numerous carbohydrate structures. This domain was incubated with trypsin and subjected to liquid chromatography electrospray ionization mass spectrometry analysis, using an electrospray orthogonal acceleration time-of-flight mass spectrometer as the detector for a capillary reversed phase HPLC separation of the digest. The inherent high mass resolution afforded by this instrument provides both ion charge state determination and high accuracy mass measurement that are of significant advantage in defining such highly complex mixtures.  相似文献   
9.
Overall, in the air pollution control field, odor concentration and intensity as well as hedonic rating have been well studied to the point where some level of standardization is being developed or is already in place. However, there has been no standardization with respect to odor quality characterization. There is now sufficient understanding of the types of odorous compounds that can arise from wastewater treatment processes to develop an odor classification scheme. This article presents the first wastewater odor wheel or classification scheme that should form the foundation for the evolution of odor quality data reporting with links to chemical causes.  相似文献   
10.
Two mollusc-specific neurotoxic peptides from the venom of the molluscivorous snail Conus pennaceus are described. These new toxins block acetylcholine receptors (AChR) of cultured Aplysia neurons. Bath application of 0.5-1 microM toxin induces 5-10-mV membrane depolarization, which recovers to the control level within 1-3 min in the presence of the toxin. This response is blocked by 1 mM hexamethonium. Concomitantly with the transient depolarization, the toxins block approximately 90% of the depolarizing responses evoked by brief iontophoretic application of acetylcholine. The pharmacology and amino acid sequences of the toxins (alpha PnIA, GCCSLPPCAANNPDYC-NH2; alpha PnIB, GCCSLPPCALSNPDYC-NH2) enable their classification as novel alpha-conotoxins. The sequences differ from those of previously described alpha-conotoxins in a number of features, the most striking of which is the presence of a single negatively charged residue in the C-terminal loop. This loop contains a positively charged residue in piscivorous venom alpha-conotoxins. In contrast to other alpha-conotoxins, which are selective for vertebrate skeletal muscle nicotinic ACh receptors, these Conus pennaceus toxins block neuronal ACh receptors in molluscs. As such they are new probes which can be used to define subtypes of ACh receptors, and they should be useful tools in the study of structure-function relationships in ACh receptors.  相似文献   
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