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1.
Scenarios are possible future states of the world that represent alternative plausible conditions under different assumptions. Often, scenarios are developed in a context relevant to stakeholders involved in their applications since the evaluation of scenario outcomes and implications can enhance decision-making activities. This paper reviews the state-of-the-art of scenario development and proposes a formal approach to scenario development in environmental decision-making. The discussion of current issues in scenario studies includes advantages and obstacles in utilizing a formal scenario development framework, and the different forms of uncertainty inherent in scenario development, as well as how they should be treated. An appendix for common scenario terminology has been attached for clarity. Major recommendations for future research in this area include proper consideration of uncertainty in scenario studies in particular in relation to stakeholder relevant information, construction of scenarios that are more diverse in nature, and sharing of information and resources among the scenario development research community.  相似文献   
2.
The authors show that a narrowband noise (NBN) is perceived as longer when presented immediately after a wideband noise (WBN), compared to when the WBN is absent. This effect depended on the WBN’s frequency spectrum overlapping that of the NBN, and it increased as the duration of the WBN increased up to 300 ms. It decreased when a silent gap was introduced between the WBN and NBN, but remained significant for an easily detectable gap of 40 ms. A correlate of the effect was observed in the mismatch negativity (MMN) to a deviant stimulus, consisting of a WBN + NBN, presented in a sequence of more common isolated WBNs. The MMN latency was longer for an on-frequency than for an off-frequency WBN; and, more importantly, the size of this difference correlated across participants with the difference in perceived duration. A rhythm-adjustment experiment showed that the presence of an on-frequency WBN immediately preceding a tone caused that tone to be heard as starting earlier than when the WBN was absent. The results are discussed in relation to the continuity illusion and models of duration encoding. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
Reversed-phase liquid chromatography (RPLC) is commonly used to analyze nonvolatile components in food. However, polar low-molecular-weight compounds such as hydrophilic amino acids, di- and tripeptides, and organic acids are often not sufficiently retained and represent a challenge for RPLC. Hydrophilic interaction liquid chromatography in combination with electrospray mass spectrometry (HILIC-ESI-MS) on a carbamoyl-derivatized stationary phase was successfully employed to separate free amino acids and small polar peptides in complex food matrixes such as wheat gluten hydrolysate and Parmesan cheese. Glutamyl dipeptides were separated in a sequence-specific order with peptides with N-terminal glutamic acid residues eluting prior to their reverse sequence analogues. ESI-MSn detection in the positive ionization mode provided the necessary information to unambiguously identify isobaric peptides due to their characteristic fragmentation patterns. The technique also proved useful to separate and identify glycoconjugates between amino acids and reducing sugars (Amadori compounds). The investigation of organic acids present in food used a mobile phase comprising ammonium acetate buffer at pH 7 and mass spectrometric detection in the negative ionization mode.  相似文献   
4.
Hexagonal aluminum nitride (AlN) crystals were synthesized by microwave method with ammonium chloride used as an additive. Starting mixtures consisted of Al powder, NH4Cl, and urea as a fuel taken in a 1: 3: 1 ratio. The microwave oven operated at 630 W, the synthesis time was 10, 30, 60, and 120 min. The results showed that the pure AlN powder with regular and fine grains could be obtained in 30 min. The synthesized powders were characterized by TGA/DTA, XRD, FT-IR, UV-VIS, SEM, and TEM.  相似文献   
5.
Maladaptive social behavior is one of the defining characteristics of psychopathic personality disorder. Nevertheless, maladaptive social behavior has only rarely been observed among psychopaths in experimentally controlled situations. The authors assessed the behavior of criminal psychopaths from high-security psychiatric hospitals in a computer simulation of a social dilemma situation. The psychopaths showed a markedly higher proneness to competitive (i.e., noncooperative) behavior than did healthy adults from the general population. The odds ratio between defection and being a psychopath was estimated at 7.86 in the sample. The probability to choose selfish instead of cooperative behavior was significantly linked to the following subscales of the Psychopathy Personality Inventory-Revised (S. O. Lilienfeld & M. R. Widows, 2005): rebellious nonconformity, Machiavellian egocentricity, and the total score. On average, the psychopathic participants accumulated higher gain and more strongly exploited their counterpart than did the healthy participants. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
Summary A procedure for the identification of sulphonamides in edible animal tissues by two-dimensional high-performance thin-layer chromatography is described. Sixteen sulphonamides can be detected at an absolute level of 10 ng. The absolute detection limit of the sulphonamide standards is 1 ng. After extraction of the sulphonamides with chloroform/acetone, the acidified extract is concentrated and purified using a cation-exchange solid phase extraction column. The column is treated with ammonia vapour and the sulphonamides are then eluted with methanol. Blank samples of edible animal tissues spiked with sulphonamides (frequently used in Belgium) result in very good separation.
Identifizierung von sulfonamiden in geweben von schlachttieren mittels zweidimensionaler hochleistungsdünnschichtchromatographie
Zusammenfassung Eine Methode zur Identifizierung von Sulfonamiden in Geweben von Schlachttieren mittels zweidimensionaler Hochleistungsdünnschichtchromatographie wird beschrieben. 16 Sulfonamide können identifiziert werden, wobei die absolute Empfindlichkeitsgrenze bei 10 ng liegt. Die absolute Nachweisgrenze für die Referenzsubstanzen liegt bei 1 ng. Nach Extraktion der Sulfonamide mit Chloroform-Aceton wird die angesäuerte Extraktlösung auf einer Kationenaustausch-Extraktionssäule eingeengt und gereinigt. Die Säule wird mit Ammoniakdämpfen behandelt und die Sulfonamide werden anschliessend mit Methanol eluiert. Die den Gewebeextrakten zugefügten in Belgien häufig verwendeten Sulfonamide konnten sehr gut voneinander getrennt werden.
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7.
European Food Research and Technology - A method is described for the quantitative determination of the residual solvents isopropanol and propylene glycol in soft drinks. The proposed methods are...  相似文献   
8.
BACKGROUND: Community-based therapeutic care (CTC) is a new strategy in the arsenal of techniques to manage complex nutritional emergencies in rural communities. The CTC approach uses a newly developed ready-to-use therapeutic food, Plumpynut, to rehabilitate severely malnourished children in their home communities. Emerging literature has suggested the CTC strategy yielded results that were superior to those of programs limited to therapeutic feeding centers, as measured by rates of coverage and numbers of children rehabilitated. OBJECTIVE: To compare the effectiveness of the CTC strategy in combination with conventional treatments for acute malnutrition. The expectation was that this program would support the growing consensus on the effectiveness of CTC strategies. METHODS: Data from monitoring the initial phase of program implementation were reviewed to ascertain program impact. The number of children participating and the outcome of their participation were assessed. RESULTS: Families became key participants in the rehabilitation of their children, and communities became strengthened through the mobilization of local networks and the improved knowledge base of local health workers. Recovery rates were comparable with international standards, and coverage far exceeded that of traditional center-based care. CONCLUSIONS: CTC is an important tool to effectively address nutritional emergencies and may be a valuable entry point for long-term development, since it fosters capacity building and improvement in local communities. CTC programs may eventually be viewed as the entry point for more sustained development-oriented interventions, thus helping make the transition from relief to development.  相似文献   
9.
Sprouty proteins are widely accepted modulators of receptor tyrosine kinase-associated pathways and fulfill diversified roles in cancerogenesis dependent on the originating cells. In this study we detected a high expression of Sprouty3 in osteosarcoma-derived cells and addressed the question of whether Sprouty3 and Sprouty1 influence the malignant phenotype of this bone tumor entity. By using adenoviruses, the Sprouty proteins were expressed in two different cell lines and their influence on cellular behavior was assessed. Growth curve analyses and Scratch assays revealed that Sprouty3 accelerates cell proliferation and migration. Additionally, more colonies were grown in Soft agar if the cells express Sprouty3. In parallel, Sprouty1 had no significant effect on the measured endpoints of the study in osteosarcoma-derived cells. The promotion of the tumorigenic capacities in the presence of Sprouty3 coincided with an increased activation of signaling as measured by evaluating the phosphorylation of extracellular signal-regulated kinases (ERKs). Ectopic expression of a mutated Sprouty3 protein, in which the tyrosine necessary for its activation was substituted, resulted in inhibited migration of the treated cells. Our findings identify Sprouty3 as a candidate for a tumor promoter in osteosarcoma.  相似文献   
10.
A crucial safety measure to be strictly observed in the operation of heavy-water nuclear power plants is the mandatory regular inspection of the concentration of deuterium penetrated into the zircaloy fuel vessels. The existing standard method requires a tedious, destructive, and costly sample preparation process involving the removal of the remaining fuel in the vessel and melting away part of the zircaloy pipe. An alternative method of orthogonal dual-pulse laser-induced breakdown spectrometry (LIBS) is proposed by employing flowing atmospheric helium gas without the use of a sample chamber. The special setup of ps and ns laser systems, operated for the separate ablation of the sample target and the generation of helium gas plasma, respectively, with properly controlled relative timing, has succeeded in producing the desired sharp D I 656.10 nm emission line with effective suppression of the interfering H I 656.28 nm emission by operating the ps ablation laser at very low output energy of 26 mJ and 1 μs ahead of the helium plasma generation. Under this optimal experimental condition, a linear calibration line is attained with practically zero intercept and a 20 μg/g detection limit for D analysis of zircaloy sample while creating a crater only 10 μm in diameter. Therefore, this method promises its potential application for the practical, in situ, and virtually nondestructive quantitative microarea analysis of D, thereby supporting the more-efficient operation and maintenance of heavy-water nuclear power plants. Furthermore, it will also meet the anticipated needs of future nuclear fusion power plants, as well as other important fields of application in the foreseeable future.  相似文献   
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