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81.
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83.
On the basis of the data presented above the following conclusions may be drawn. 1. The molecular ion peaks of most of the compounds examined are relatively weak but usually easily discernible to permit molecular weight determination. 2. The mass spectra of benzilate esters exhibit a relatively intense peak at m/e 183, and monitoring of this ion can serve as a means for preliminary screening for the presence of this type of a system. 3. Related esters exhibit a similar type of fragmentation resulting in a fragment ion analogous to m/e 183 but shifted by the appropriate number of mass units according to the substituents present. 4. Cleavage of the piperidine ring-ester oxygen bond in 3 and 4-substituted isomers is followed by selective losses of hydrogen radicals to produce ions of type e, f, and g as indicated above. It is significant that in a related piperidine ring system (methylphenidate) substituted in the 2 position, the same type of cleavage results in no further hydrogen losses [16] because of charge stabilization from the ring nitrogen (ion j, Fig. 17) [17]. In other words, the tendency to form a conjugated ion following initial bond cleavage can serve as a means for identifying the position of substitution on the ring and for distinguishing positional isomers.  相似文献   
84.
The limited disruption produced in tissue simulant by the rifle and bullets used in the Stockton, California, schoolyard shooting is entirely consistent with the autopsy reports on the five children who died of their wounds. It is also entirely consistent with well-documented battlefield studies and with previous tissue-simulant studies from many laboratories. It is inconsistent with many exaggerated accounts of assault-rifle wounding effects described by the media in the aftermath of this incident. This information should be documented for the historical record. However, the critical reason for correcting the misconceptions produced by media reaction to this incident is to prevent inappropriate gunshot-wound treatment.  相似文献   
85.
This study examines consistency in opinion on a variety of important state and national policy questions. The data come from a two-wave panel study of adult Floridians conducted in 1981 and 1982. Wide variations in consistency of opinion over the 1-year period are found. Salience has an important impact on consistency, with respondents who find an issue salient almost always exhibiting more consistent opinions, but salience cannot explain the variations in consistency across issues. The level of government on which the issue is focused (national or state) has no bearing on consistency. Most important, the particular nature of the issue itself, especially how central it is to the individual and how long it has occupied the political agenda (maturity), affects consistency of opinion. Centrality and maturity both contribute to issue attitude consistency and even can compensate for one another. Both highly central new issues and remote old issues can produce consistent attitudes, but deficiences in centrality seem to override issue maturity. These findings illustrate the value of looking beyond opinion distributions to the meaning of the survey response. With information on consistency and its sources, the public opinion analyst can interpret polling results intelligently, and the study of public opinion can become more objective and scientific.  相似文献   
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The routine production of a cast of a shoe-print taken in soil provides information other than shoe size and gait. Material adhering to the surface of the cast represents the preservation of the moment of footprint impression. The analysis of the interface between the cast and soil is therefore a potentially lucrative source of information for forensic reconstruction. These principles are demonstrated with reference to a murder case which took place in the English Midlands. The cast of a footprint provided evidence of a two-way transfer of material between the sole of a boot and the soil of a recently ploughed field. Lumps of soil, which had dried on a boot, were deposited on the field as the footprints were made. Pollen analysis of these lumps of soil indicated that the perpetrator of the imprint had been standing recently in a nearby stream. Fibre analysis together with physical and chemical characteristics of the soil suggested a provenance for contamination of this mud prior to deposition of the footprint. Carbon/nitrogen ratios of the water taken from the cast showed that distilled water had been used thus excluding the possibility of contamination of the boot-soil interface. It was possible to reconstruct three phases of previous activity of the wearer of the boot prior to leaving the footprint in the field after the murder had taken place. This analysis shows the power of integrating different independent techniques in the analysis of hitherto unrecognised forensic materials.  相似文献   
88.
This study explored the sense of community among women (n = 21) and women with children (n = 30) living in Oxford Houses, with emphasis on how the presence of children might affect the household. Sense of community did not vary between participants with more or less than three months residence. Residents reported very high levels of satisfaction with the home, possibly because of a ceiling effect of little room for increases in their sense of community over time. Participants reported that they were getting along with the children in the home, that mothers could count on babysitting help, and that the children had a positive effect on the household and their own recovery process. This effect did not differ between mothers and non-mothers, suggesting that non-mothers might view the children in the home with a sense of responsibility and sensitivity comparable to that of the mothers. Implications are discussed.  相似文献   
89.
In this paper, we review the result of research conducted in the context of a 13-year collaborative partnership between DePaul University and a community-based, self-run, residential substance abuse recovery program called Oxford House. This collaborative effort highlights several examples of the research and action activities fostering a positive alliance that benefited both the research team and the Oxford House community. It also proposed practical guidelines for developing effective action research collaboratives that may be helpful to others who desire to cultivate and maintain similar mutually beneficial partnerships; including such processes as the development of trust, respecting the personal experiences of the community members and group, commitment to serving the community, validating findings with organization members, and accountability.  相似文献   
90.
Jason C. Sides Reubin O'D. Askew School of Public Administration and Policy, Florida State University, Tallahassee, FL 32306 e-mail: rjackson{at}garnet.acns.fsu.edu (corresponding author) e-mail: jcs6605{at}garnet.acns.fsu.edu Examining the influence of campaign tone on individual turnoutin the 1990 U.S. Senate elections, this note revisits Kahn andKenney's conclusion that the political profile of citizens (asbased on partisanship, level of political interest, and levelof political expertise) conditions their responsiveness. Implementingan appropriate modeling strategy for making group comparisons,our analyses do not provide statistical support for the conditionaleffects that they highlight. More generally, our results doreinforce Kahn and Kenney's finding that negativity in toneof news coverage mobilizes citizens, but they do not revealsignificant turnout influence for television advertising tone.  相似文献   
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