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111.
The analysis of gamma-hydroxybutyric acid (GHB) is problematic because it is hygroscopic, it lacks a good UV chromophore, and it undergoes heat-induced cyclization. This paper presents a new method utilizing ion-exchange chromatography (IC) with conductivity detection. The simple sample preparation, rapid analysis time, and inorganic anion detection capabilities are all advantages over the current methods. The detection of inorganic salts (formed during GHB synthesis) gives insight into the synthetic route utilized and can aid in drug seizure comparison. The developed method has a detection limit for GHB anions of 0.57 mg/L and chloride of 0.22 mg/L. A comparison of this technique with a current gas chromatography-mass spectrometry technique is presented, and a t-test found that the two methods' results are not statistically different at the 99.9% confidence level demonstrating the merits of this fast, simple, and informative IC method as a routine screening tool. 相似文献
112.
How do economic freedom and culture impact economic growth? This paper argues that culture, as measured by the World Values Surveys, and economic institutions associated with economic freedom are both independently important for economic prosperity, but the strength of their impact can be better understood only when both are included in the growth regression. Our results indicate that economic freedom is more important than culture for growth outcomes, suggesting substitutability between the two. We posit that culture is important for growth when economic freedom is absent, diminishing in significance once economic freedom is established. 相似文献
113.
114.
Gender Differences in the Educational Expectations of Urban,Low-Income African American Youth: The Role of Parents and the School 总被引:2,自引:1,他引:1
This study examined how youths’ gender is related to the educational expectations of urban, low-income African American youth,
their parents, and their teachers. As predicted, African American boys (ages 9–16) reported lower expectations for future
educational attainment than did their female counterparts. Parents and teachers also reported lower expectations for African
American boys (ages 6–16) than for girls. These findings held even when controlling for academic achievement. Contrary to
predictions, the magnitude of the difference in expectations for males vs. females did not increase as a function of youths’
age. In keeping with our hypotheses, parental expectations fully mediated the relation between youths’ gender and youths’
expectations. Finally, certain school-based factors (i.e., positive teacher expectations and positive youth perceptions of
the school environment) appeared to protect youths’ expectations from the deleterious impact of low parental expectations.
相似文献
Dana WoodEmail: |
115.
Levels of support for just world beliefs among young adults (N = 598) from four ex-Yugoslavian countries—Bosnia and Herzegovina, Croatia, the former Yugoslav Republic of Macedonia, and
Slovenia—were compared, taking into account victimization experiences and the general belief in a just world. Being a victim
affected an individual’s belief in a just world in the two less economically favored contexts: Victims of exclusion in Macedonia
and victims of war in Bosnia and Herzegovina were less likely to believe in a just world than non-victims. These victimization
variables partly explained why the mean scores of these two countries were less than those of the two others. A deleterious
effect of cumulative negative events on belief in a just world was identified, in parallel with a lower endorsement of the
belief when the first victimization occurred more recently. 相似文献
116.
A compositionally simplified analogue of a latent fingermark was created by combining single representatives of each major component of a natural fingermark. Further modified analogues were also produced each having one component removed. The aim of this study was to investigate the intermolecular interactions that occurred within these analogue samples using Fourier Transform Infrared (FT-IR) Microspectroscopy. FT-IR microspectroscopy showed that the absence of squalene and cholesterol significantly restricted the interactions between the other organic constituents within the analogue samples. Investigating the intermolecular interactions of organic compounds within a simplified analogue solution could indicate corresponding interactions that occur within natural fingermarks. These potential interactions could go on to be the target of further investigation of latent fingermark chemistry, and ultimately contribute to a better understanding of the aging processes and degradation mechanisms that take place post-deposition. 相似文献
117.
Abstract From the limited literature on older witnesses’ identification performance it is known that they are less accurate on lineups compared to younger witnesses. What is less certain is why they show this age deficit and what can be done to aid their performance. Witnesses forgot being given non-biased lineup instructions informing witnesses that the perpetrator may or may not be present. More older witnesses than younger witnesses forgot and witnesses who failed to report remembering these instructions were significantly less accurate on the lineups. In addition, the current study investigated the use of sequential lineup presentation and stringent decision criteria to aid the performance of older witnesses. Sequential presentation was beneficial to both younger and older adults when the lineup was target absent (TA) but was detrimental when the lineup was target present (TP). Stringent decision criteria had no significant beneficial effect. Future directions for aiding older witnesses’ performance are discussed. 相似文献
118.
Abstract The sporting culture, with omnipotent coaches, fierce competition for recognition and funding, and ‘win at all costs’ ethos, creates an environment conducive to sexual exploitation of athletes. Recent increased public awareness and the development of child protection policies in sport have led to the questioning of previously accepted coach-athlete relationships. This study is an exploratory investigation into male swimming coaches' perceptions of appropriateness of coach-athlete sexual relationships. Sexual relationships with athletes under the age of 16 were unanimously considered totally inappropriate. With regard to sexual relationships with athletes above the age of consent, opinions ranged from ‘totally inappropriate’ to ‘it’s a question of civil liberties.' These results are discussed in relation to how coaches have adapted their own behaviours in the face of public scrutiny but are still reluctant to restrict the rights of their fellow coaches. 相似文献
119.
Sam Johnston 《Journal of International Wildlife Law & Policy》2013,16(2):147-158
Abstract The Conference of the Parties to the Convention on Biological Diversity (Convention) has taken 114 decisions and launched programmes of work to address five biome‐based themes and thirteen cross‐cutting issues. The challenge for the Convention now is to demonstrate, through action and deed, that it is an effective vehicle for implementing this policy. In response to this challenge, the Conference of the Parties at its fifth meeting, in May 2000, decided to initiate a process to develop a Strategic Plan for the Convention that would provide an important mechanism for the implementation of this policy. This Note, which is an abridged version of document UNEP/CBD/MSP/2, has been prepared to assist participants in this Conference to provide more focused suggestions for the development of the Strategic Plan for the Convention. 相似文献
120.