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601.
J. K. McGregor 《CMAJ》1961,85(16):863-867
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David R. Biggs Robert M. Greenway Peter G. McGregor 《Entomologia Experimentalis et Applicata》1994,73(1):31-37
An electrode system consisting of a cast antimony rod with a silver chloride-coated wire as a reference electrode has been
developed to measure pH in insect gut contents. The electrode works well with buffer volumes down to 0.1 μl. Response to pH
is linear between pH 4 and 11 and equates to a change of 52.3 mV per pH unit at 18–20°C. Electrical resistance is low (0.25
MΩ), so the electrode can be used with low-impedance meters and does not require shielding from induced currents. Its useful
range lies between redox potentials −330 mV (pH 7) and +297 mV to 350 mV, corresponding to a pe + pH range of 1.4 to about
10.8. This covers reported gut pH values for most insects so far examined. Consequently the electrode is suitable for measuring
pH of gut contents from many insects that are too small to be analysed with current commercial electrodes. 相似文献
604.
BACKGROUND: Few studies have examined whether there is an association between individual medical findings and legal outcome in cases of sexual assault. This study was undertaken to determine the relation between the extent of documented physical injury and a positive legal outcome in cases of sexual assault and to determine other factors associated with the laying of charges in such cases. METHODS: In this retrospective cohort study, the authors reviewed the charts and medicolegal reports for all cases of sexual assault that were handled by the BC Women''s Sexual Assault Service in 1992 for which a police report had been filed. Information on patients'' characteristics, the nature of the assault and the extent of injury was extracted from these records. A system for scoring clinical injury was developed by 4 of the physicians at the Sexual Assault Service, and a clinical injury score was assigned for each case by one physician. The relation between the outcome (in terms of whether charges were laid) and the circumstances of the case was examined by logistic regression. RESULTS: A total of 95 cases with complete medical records and information about legal outcome were identified during the 1992 calendar year. After adjustment for income level and the patient''s knowledge of the assailant (either as an acquaintance or as his or her partner), the odds ratio (OR) for charge-laying in a sexual assault case with documented moderate to severe injury was 3.33 (95% confidence interval [CI] 1.06-10.42). Socioeconomic status above the group median (defined as annual income greater than $21,893) (OR 3.26, 95% CI 1.09-9.71) and knowledge of the assailant (OR 4.58, 95% CI 1.52-13.79) were also associated with charge-laying. Presence of genital injury per se, age of the patient and detection of sperm by microscopy at the time of examination were not associated with the laying of charges. INTERPRETATION: The results of this study show that the extent of documented injury is associated with the laying of charges in cases of sexual assault. However, many questions remain about the effectiveness of the medical component of gathering such evidence. 相似文献
605.
P. K. McGregor 《Acta ethologica》2000,3(1):3-8
The scientific value of the outcome of an experiment is closely related to its design and analysis. This article deals with
the design issues of pseudoreplication (whether the experimental design has the statistical features needed to answer the
question as posed) and execution errors (problems arising from how the experiment was conducted). Three issues of analysis
are also dealt with: the number and type of response measures to record; how measures should, and should not, be combined
into a single response measure; and how to interpret an apparent lack of response. Interactive playback is considered separately
because it raises its own specific design and analysis issues. Although the examples generally refer to video playback, these
issues are common to all experiments in behaviour.
Received: 23 September 1999 / Received in revised form: 24 February 2000 / Accepted: 25 February 2000 相似文献
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Robert McGregor 《Journal of Insect Behavior》1997,10(3):451-462
A dynamic optimization model is presented for the decision to host feed or oviposit on hosts by female parasitoids. Optimal
host utilization decisions are compared between two host types with different fitness payoffs for oviposition. The model predicts
that hosts of higher fitness value should always be used for oviposition unless the egg load approaches zero. This general
prediction is not influenced by levels of host availability or metabolic reserves, the age of the parasitoid, or the magnitude
of the fitness difference. An egg-load threshold is predicted above which lower value hosts should be used for oviposition
and below which they are used for host feeding. The position of this egg-load threshold is higher when the difference in fitness
between host types is larger. The threshold is also higher when overall host availability is high or metabolic reserves for
the production of new eggs are low. The threshold for oviposition on low-value hosts decreases to zero near the end of the
parasitoid’s life. Under conditions where high-value hosts are rarely encountered compared to low-value hosts, the model predicts
that lower value hosts should be accepted for oviposition at a lower egg-load threshold. 相似文献
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