Ethnic representation in a sample of the literature of applied psychology

A number of authors have raised concerns over the external validity of psychological research. This study examined the extent to which empirical articles include human participants from diverse ethnic backgrounds. Articles published over a 5-year period in 14 selected journals representing 3 applied sub-disciplines of psychology were examined. Of the 2,536 articles coded, only 61% indicated the ethnicity of the participants. For those articles, the ethnic compositions approximated U.S. Census estimates, with the exception of an overrepresentation of African Americans and an underrepresentation of Hispanic Americans. The results imply that although the field is apparently adequately recruiting English speakers, representation of non-English speakers should be increased. To further enhance the external validity of psychological research, ethnicity of participants should be not only specified but also analyzed in relation to the results of a study.

Ethnic representation in a sample of the literature of applied psychology

A number of authors have raised concerns over the external validity of psychological research. This study examined the extent to which empirical articles include human participants from diverse ethnic backgrounds. Articles published over a 5-year period in 14 selected journals representing 3 applied sub-disciplines of psychology were examined. Of the 2,536 articles coded, only 61% indicated the ethnicity of the participants. For those articles, the ethnic compositions approximated U.S. Census estimates, with the exception of an overrepresentation of African Americans and an underrepresentation of Hispanic Americans. The results imply that although the field is apparently adequately recruiting English speakers, representation of non-English speakers should be increased. To further enhance the external validity of psychological research, ethnicity of participants should be not only specified but also analyzed in relation to the results of a study.

Comparative avian phylogeography of Cameroon and equatorial Guinea mountains: implications for conservation

We illustrate the use of Faith's 'Phylogenetic Diversity' measure to compare the phylogeographic structure of two bird species with patterns of avian endemism across six mountains in Cameroon and Equatorial Guinea. The Mountain Greenbul and Cameroon Blue-headed Sunbird showed phylogeographic patterns that together defined three biogeographic regions: Bioko, Mt. Cameroon, and the northern mountains of Cameroon. In contrast, the distributions of endemic species were largely a function of geographical distance, with close mountains sharing more endemic species than distant mountains. Moreover, for both species, populations on Mt. Cameroon were distinctive with respect to the ecologically relevant character bill size. Our results, while preliminary, illustrate the utility of a comparative approach for identifying geographical regions that harbour evolutionarily distinct populations and caution against using only the distributional patterns of endemics to prioritize regions for conservation. Results show that patterns of endemism may not be concordant with patterns of phylogenetic diversity nor morphological variation in a character important in fitness. While incorporation of additional species from unrelated taxa will be necessary to draw definitive conclusions about evolutionarily distinct regions, our preliminary results suggest a conservation approach for the Afromontane region of the Gulf of Guinea that would: (i) emphasize protection of both Bioko and Mt. Cameroon, thereby maximizing preservation of within-species phylogenetic and morphologic diversity; (ii) emphasize protection within the northern mountains to further conserve intraspecific phylogenetic diversity and maximize protection of endemic species.

Effects of mothers' locus of control for child improvement in a developmentally delayed sample

A potentially important variable that has received little attention in the literature is the locus of control (LOC) a caregiver holds for child improvement, including its influence on the caregiver's treatment compliance and on actual child improvement. In this study, 131 mother-child dyads were assessed across 1 year, to evaluate the utility of the LOC construct in a practice setting. Children were approximately 4 years old at the first assessment, and all of them had been diagnosed with a developmental disability. Mothers' compliance with treatment (mothers' attendance at sessions; teachers' ratings of mothers' support and knowledge) was tracked, and measures of child development status and mothers' locus of control were administered. Statistical results indicated that mothers' locus of control was not significantly correlated with children's gains in development over the year. The mothers' beliefs about whether the child or chance would be responsible for improvement were associated with lower compliance with treatment, whereas the mothers' beliefs that child improvement was attributable to professional intervention were associated with enhanced involvement in treatment.

Genetic evidence for the effect of a postglacial population expansion on the phylogeography of a North American songbird

Phylogeographical studies of Nearctic songbirds conducted to date have yielded unexpectedly low levels of genetic differentiation and weak phylogeographical structure in mitochondrial DNA lineages as compared with species studied in Neotropical areas. Factors leading to this pattern may include (i) gene flow, (ii) population expansions from bottlenecked populations, and (iii) selective sweeps. Here we provide evidence for the role played by Pleistocene postglacial population expansions on the phylogeography of MacGillivray's warbler (Oporornis tolmiei), a long-distance migratory bird. Samples from 12 breeding localities in the temperate USA were compared with those from two localities in north-eastern Mexico. The former showed evidence of a Late Pleistocene population expansion as indicated by low haplotype and nucleotide diversity, a star-like phylogeny of alleles, and a mismatch distribution indicating a sudden increase in effective population size. By contrast, the Mexican population showed high levels of genetic diversity and a mismatch distribution as expected for a population unaffected by sudden demographic change. Haplotypes from the two regions formed two distinct phylogroups which separated roughly one million years ago according to a conventional molecular clock for songbirds. This study provides support for the Pleistocene expansion hypothesis in MacGillivray's warbler and suggests that postglacial expansion of bottlenecked populations is responsible for the lack of variation and structure reported for most North American songbird species.

A test of alternative models of diversification in tropical rainforests: ecological gradients vs. rainforest refugia

Comparison of mitochondrial and morphological divergence in eight populations of a widespread leaf-litter skink is used to determine the relative importance of geographic isolation and natural selection in generating phenotypic diversity in the Wet Tropics Rainforest region of Australia. The populations occur in two geographically isolated regions, and within each region, in two different habitats (closed rainforest and tall open forest) that span a well characterized ecological gradient. Morphological differences among ancient geographic isolates (separated for several million years, judging by their mitochondrial DNA sequence divergence) were slight, but morphological and life history differences among habitats were large and occurred despite moderate to high levels of mitochondrial gene flow. A field experiment identified avian predation as one potential agent of natural selection. These results indicate that natural selection operating across ecological gradients can be more important than geographic isolation in similar habitats in generating phenotypic diversity. In addition, our results indicate that selection is sufficiently strong to overcome the homogenizing effects of gene flow, a necessary first step toward speciation in continuously distributed populations. Because ecological gradients may be a source of evolutionary novelty, and perhaps new species, their conservation warrants greater attention. This is particularly true in tropical regions, where most reserves do not include ecological gradients and transitional habitats.

Health and educational outcomes of children who experienced severe neonatal medical complications

To determine the long-term developmental and educational outcomes of a sample of low birthweight infants with intraventricular hemorrhage (IVH), the authors conducted developmental assessments and interviews 8 years after the initiation of an early intervention project. At the time of the follow-up, 62% of the children were experiencing some developmental or behavior problems, with visual impairments, cerebral palsy, and attention deficits occurring most frequently. Grade of IVH and the number of days spent in the neonatal intensive care unit were the best predictors of later developmental delays. The sample also scored below average on school achievement; approximately 30% of those in school were eligible for special education services. These findings corroborate results from investigations with similar populations whose birth characteristics put them at risk for subsequent developmental delay.

Copper deficiency increases cytochrome P450-dependent 7-ethoxyresorufin-O-deethylase activity in rat small intestine

Although impaired heme synthesis during copper deficiency may limit the production and function of hemoproteins, little is known about the effects of copper deficiency on the cytochromes P450, an important family of hemoproteins, in the small intestine. A series of experiments was conducted to examine the effects of copper deficiency on cytochrome P450 content, ethoxyresorufin-O-deethylase (EROD) activity, and NADPH-cytochrome P450 reductase activity in rat small intestine. Sixteen hours after a single oral administration of 5,6-benzoflavone (BF), an inducer of cytochromes P4501A1 and P4501A2, intestinal cytochrome P450 content was elevated as indicated by the CO-difference spectrum of the reduced cytochrome and by immunoblotting using anticytochrome P4501A1/1A2. However, cytochrome P450 content, measured by either method following BF induction, was not affected by copper deficiency. Thus, copper deficiency did not impair the availability of heme for cytochrome P450 synthesis in the small intestine. Even though copper deficiency did not affect intestinal cytochrome P450 content, EROD activity, which is a cytochrome P450-associated monooxygenase activity, was 9-fold higher in copper-deficient rats compared with controls following BF treatment. The finding that copper deficiency has no effect on intestinal cytochrome P450 content suggests that the increased EROD activity results from an effect of copper deficiency on the cytochrome P450 reductase component of the monooxygenase system. Measurement of cytochrome P450 reductase activity showed a 2-fold increase in the small intestines of copper-deficient rats compared with controls. It is possible, therefore, that increased intestinal cytochrome P450 reductase activity during copper deficiency increases EROD activity by facilitating the flow of electrons to cytochrome P450 during the redox cycle that cytochrome P450 undergoes during the O-deethylation of ethoxyresorufin.

In vitro fracture behavior of ceramic and metal-ceramic restorations

PURPOSE

Failed crowns and failure load data were studied to gain insights into the fracture behavior of prostheses under incisal-directed, load-to-failure testing.

MATERIALS AND METHODS

Incisor crowns (n = 68) were fabricated: two all-ceramic groups (feldspathic veneer on high-strength core), differing in core design, and two metal-ceramic groups, differing in metal oxidation time (30 seconds v 3 minutes). Crowns were loaded to failure on their incisal edge. Gross visual, microscopic, and elemental microprobe analyses of failed crowns were coupled with Weibull analysis of the failure load data.

RESULTS

Failure loads were higher for the normal oxidation time (TN) than for the extended oxidation time (TE) metal-ceramic crowns (P < .02), but both groups had indistinguishable Weibull moduli indicating the possibility of a common failure origin. Fracture behavior and Weibull results both implicated the oxide layer as being the origin of failure. The ratio of fracture loads (TE/TN) corresponded well with calculated oxide-volume ratios. Failure loads were lower for the all-ceramic than for the metal-ceramic crowns (P < .001). Fifty percent of the all-ceramic crowns failed by delamination of veneering glass alone, leaving a thin layer of residual glass on the core surface. Scanning electron microscope views showed that delamination occurred 10 to 50 microns away from the core-veneer interface. Electron microprobe elemental analysis of the core-veneer interface showed that residual core infiltration glass was not present on the core surface and that chemical alterations in the veneering glass were apparently limited to less than a 2- to 3-microns thick layer.

CONCLUSIONS

Failure for both restorative systems involved interfacial stresses with crack propagation occurring at or near the core-veneer interface. The weaker interface in the metal-ceramic system probably resulted from an increase in surface oxide volume, irrespective of any change in its adherence or physical properties. For the ceramic crowns, delamination crack fronts appeared to propagate through chemically unaltered veneering porcelain. Both the Weibull moduli and characteristic strengths were indistinguishable between either of the two ceramic core designs or between groups failing from delamination with or without core cracking/failure. This is consistent with delamination being the primary fracture process during failure. Clinical implications should not be drawn from results of this study because no correlation is known to have ever been established between clinical behavior and incisal load-to-failure results.

Respiratory responses of elite oarsmen, former oarsmen, and highly trained non-rowers during rowing, cycling and running

The position of the body and use of the respiratory muscles in the act of rowing may limit ventilation and thereby reduce maximal aerobic power relative to that achieved in cycling or running, in spite of the greater muscle mass involved in rowing. This hypothesis was investigated for three groups of male subjects: nine elite senior oarsmen, eight former senior oarsmen and eight highly trained athletes unskilled in rowing. The subjects performed graded exercise to maximal effort on a rowing ergometer, cycle ergometer and treadmill while respiratory minute volume (VE) and oxygen consumption (VO2) were monitored continuously. The VE at a given VO2 during intense submaximal exercise (greater than 75% of maximal VO2) was not significantly lower in rowing compared with that in cycling and treadmill running for any group, which would suggest that submaximal rowing does not restrict ventilation. At maximal effort, VO2, and VE for rowing were less than those for the other types of exercise in all the groups, although the differences were not statistically significant in the elite oarsmen. These data are consistent with a ventilatory limitation to maximal performance in rowing that may have been partly overcome by training in the elite oarsmen. Alternatively, a lower maximal VE in rowing might have been an effect rather than a cause of a lower maximal VO2, if maximal VO2 was limited by the lower rate of muscle activation in rowing.

Effects of subliminal stimuli on unconscious processing of anxiety: an examination of implicit perception

Researchers in cognitive psychology generally accept that information, including emotions, may be processed outside of awareness. Some have postulated that anxiety may be induced by stimuli presented below the level of detection, a process called implicit perception; however, conflicting findings as to the validity of subliminal stimuli in influencing anxiety have been reported over the past decade. In the present study, 39 subjects were exposed to either positive, negative, or neutral subliminal stimuli, and half the subjects were informed as to the type of stimuli they received. All subjects were monitored for frontalis muscle tension, a physiological indicator of anxiety, on an electromyograph (EMG). No significant effects of the exposure upon EMG recordings were noted. Awareness of the type of stimuli presented had a small but insignificant effect. These results, although tentative, when replicated would question the validity of subliminal visual presentation in altering emotive states.

Depressive symptomatology and interaction behaviors of mothers having a child with disabilities

Previous research has indicated that parents who raise children having disabilities report greater emotional distress than other parents. To investigate the association between symptoms of depression and maternal behaviors, interactions between 48 mothers and children having disabilities were rated. Measures of maternal depression and child functioning were also administered. Analyses indicated that mothers reported a relatively large number of symptoms often associated with depression. However, reports of depressive symptomatology were not meaningfully related to the children's developmental status or parent-child interaction behaviors.

A prospective evaluation of a simplified captopril test for the detection of renovascular hypertension

Renovascular hypertension is potentially curable but of low prevalence. A previous retrospective study has demonstrated the use of a potentiated increase in plasma renin activity after captopril administration as a diagnostic test for renovascular hypertension; this requires two blood samples for plasma renin activity determination and three inclusive criteria for a positive test result. We applied this test prospectively to screen 100 hypertensive patients for renovascular hypertension. We evaluated 29 patients with renovascular hypertension; the remainder were diagnosed as having essential hypertension. In our patient population, a postcaptopril plasma renin activity of 5.7 ng of angiotensin per milliliter per hour (ngAl.mL-1.h-1) or greater had a 100% sensitivity and an 80% specificity for renovascular hypertension. An absolute increase in plasma renin activity with captopril of 4.7 ngAl.mL-1.h-1 or greater had a lower sensitivity of 90% and a specificity of 87%, whereas a fractional increase in plasma renin activity after captopril of 150% or higher had the lowest sensitivity of 69% and a specificity of 86%. A subgroup analysis of 38 patients who were receiving diuretic therapy demonstrated that the test sensitivity was unchanged but the specificity was reduced. In conclusion, a single postcaptopril plasma renin activity value of 5.7 ngAl.mL-1.h-1 or greater is a simplified screening test for renovascular hypertension, with excellent sensitivity and acceptable specificity. This test is well tolerated, inexpensive, and easy to perform.

The captopril glomerular filtration rate renogram in renovascular hypertension

Administration of captopril to animals with two-kidney, one clip, renovascular hypertension (RH) lowers the glomerular filtration rate (GFR) in the clipped kidney. The authors therefore tested the hypothesis that a decrease in GFR after captopril administration would identify patients with RH. Total GFR was measured by the plasma disappearance of Tc-99m-diethylenetriaminepentaacetic acid (DTPA) after bolus injection and single-kidney GFR from renal uptake of DTPA assessed by renography. The authors studied six patients with arteriosclerotic RH who had strongly lateralizing renal vein renin levels and greater than 80% stenosis of the renal artery to that kidney. Results were contrasted with those of six patients with essential hypertension (EH) with a similar mean arterial blood pressure (MABP). Captopril (50 mg orally) increased total GFR (ml/min) in all patients with EH (102 +/- 8 to 120 +/- 12, P less than 0.005). However, GFR decreased in patients with RH (73 +/- 8 to 61 +/- 9, P less than 0.05) after captopril. Although the single-kidney GFR of patients with RH decreased in all six stenotic kidneys (27 +/- 4 to 21 +/- 5, P less than 0.02), it did not change consistently in the contralateral kidneys (45 +/- 8 to 40 +/- 6, N.S.). Clonidine (0.3 mg) also lowered MABP in patients with RH but, unlike captopril, it did not reduce total kidney GFR (75 +/- 10 to 79 +/- 11, N.S.). In conclusion, short-term captopril administration increases GFR in patients with EH, but decreases it in those with RH. This action is unrelated to its depressor response.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood parasites of birds in Cameroon

Birds from south-central Cameroon, western Africa, were surveyed for blood parasites from August to October 1986. Of 331 birds examined, representing 65 species of 15 families and 6 orders (mostly passerines), 55 (17%) were found to be infected with 1 or more genera of hemotropic parasites. These included: Haemoproteus spp. (11% prevalence), Leucocytozoon spp. (3%), Plasmodium spp. (2%), Trypanosoma spp. (1%), and microfilariae of filariid nematodes (1%). Several new host-parasite associations were identified.

Diagnostic uses of angiotensin-converting enzyme inhibitors in renovascular hypertension

The response to angiotensin-converting enzyme inhibitors (ACEIs) can be of considerable help in the diagnosis of human renovascular hypertension (RVH) in three settings. First, a particularly dramatic antihypertensive response or a decline in glomerular filtration rate (GFR), as indexed by a rise in serum creatinine or blood urea nitrogen concentrations, are useful clues to the presence of renovascular hypertension. Second, an exaggerated rise in plasma renin activity (PRA) after short-term captopril administration is a very promising screening test for this condition. Third, ACEI-induced changes in single-kidney hemodynamics (assessed by renography) may be helpful in confirming the diagnosis and offers the prospect of localizing the ischemic kidney.

Hearing loss in pediatric meningitis

Bacterial meningitis is the leading cause of acquired sensorineural hearing loss in children. Acquired hearing loss can have a devastating effect on a child's speech, language and eventual intellectual development, especially when the hearing loss occurs before the child learns to talk. If an immediate referral for audiologic testing is not made, valuable time is lost in obtaining hearing aids and habilitative/rehabilitative services for children during the critical period of language development.

Clinical evaluation of three urine screening tests

Evaluations of screening tests for bacteriuria have traditionally compared the test results with those of quantitative urine cultures. However, many patients with symptomatic urinary tract infections can have less than 10(5) CFU/ml in their urine. Therefore, the results of urine culture and three screening tests (Bac-T-Screen, Chemstrip LN [which tests for leukocyte esterase and nitrate reductase], and Gram stain) were correlated with the clinical classification of urinary tract infection. The Bac-T-Screen test detected 98, 93, and 100% of the infections classified as probable, possible, and asymptomatic, respectively. In contrast, the Gram stain, leukocyte esterase, and nitrate reductase tests were all insensitive screening tests for infection. Additionally, only 45% of the patients with probable infections had greater than or equal to 10(5) CFU/ml. Thus, the majority of infected patients would not have been detected if quantitative urine cultures were used alone.

Health insurance coverage of the unemployed

Of 1,332 unemployed individuals in the Detroit area interviewed in late 1983, 51% did not have health insurance. Lack of insurance was directly related to length of unemployment. Of those unemployed 3 months or less, 31% had no insurance, as compared with 56% of those unemployed more than 3 years. For the most part, these were not the chronically uninsured: 78% of them were insured when they were employed. Three fourths of those without insurance were not covered by Medicaid either. These findings suggest that during the latest economic recession, the problem of health insurance loss due to losing one's job was more severe than had been assumed by most policymakers.