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PubMed1991

Other-race face perception.

The other-race effect (or own-race bias or cross-racial identification effect) refers to the finding that recognition memory tends to be better for faces of members of subjects' own race than for faces of members of other races. The current study was designed to test the hypothesis that perceptual skills specific to identifying faces of particular racial groups contribute to this effect. On each of 50 trials, a photograph of a face was tachistoscopically presented for 120 ms, followed by a pattern mask and then a plain-view test pair composed of the previously presented face and a matched foil. As predicted, an other-race effect was obtained on this perceptual task: White subjects performed significantly more poorly on trials involving African American faces than on trials involving White faces, whereas no such difference was obtained among African American subjects.

Adult↗
PubMed1993

Study of a contact between two chromosomally monomorphic races of Sorex araneus L. (common shrew).

One hundred and twelve specimens of the common shrew from 21 populations in NE Poland were studied from an area of contact between chromosomal race II (metacentric chromosomes: hi, ko, gm, np) and race VII (ki, hn, gr, mp). No direct contact was found between the races in the study area; there were no mixed or hybrid populations. The shortest distance between populations of the two races was 1.2-1.6 km. Possible explanations for this pattern of the races' disjunction are discussed.

Animals↗
PubMed2002

Visceral adipose tissue in women: longitudinal study of the effects of fat gain, time, and race.

OBJECTIVE: To determine the effects of fat gain, time, and race on the accumulation of visceral adipose tissue (VAT) in a group of normal-weight premenopausal women. RESEARCH METHODS AND PROCEDURES: Sixty-five women participated in the study (32 African American and 33 white). The mean age of subjects was 34 +/- 6 years (range, 22 to 47 years). Eligible subjects were women who had body mass indices <25 kg/m(2) at baseline and who had completed evaluations at baseline and at follow-up year 1, without intervention. A subset of subjects was reevaluated annually for up to 4 years. Body composition was assessed by DXA, and VAT was determined from a single computed tomography scan. A linear mixed model was used to examine changes in VAT over time, with total body fat as a covariate RESULTS: Total fat mass was not significantly different between races at baseline and increased significantly in both groups over time (p < 0.001). Time-related increases in total body fat were greater in African-American women (p < 0.01). VAT was significantly higher in white women at baseline (p < 0.01) and increased significantly over time in both races (p < 0.01), but remained higher in white women (p < 0.001). Increases in VAT, relative to total body fat, were greater than the increases in total body fat over time, independent of age and race (p < 0.001). DISCUSSION: Gaining total body-fat mass results in a higher increase in VAT, relative to total body fat, regardless of race and age, although African-American women maintain a lower VAT levels across time.

Adipose Tissue↗
PubMed1985

Physical fitness of paraplegics in full wheelchair marathon racing.

The wheelchair marathon is one of the most difficult sports for participants with much uncertainty regarding the security of the paraplegics. The physical fitness of paraplegics has been examined regularly since The Oita International Wheelchair Marathon (half marathon) was inaugurated (1981). A full marathon (42.195 km) was adopted at The 3rd Meeting (1983). The individual equations between heart rate (HR) and oxygen consumption VO2 were drawn from the preliminary test on the subjects who were expected to be among the top finishers in these races. VO2 during these races was indirectly estimated and showed a fairly low value (35.0 +/- 3.8 ml/kg/min in the full race, 32.7 +/- 6.3 ml/kg/min in the half race respectively) in comparison with able-bodied elite runners. However, the paraplegic participants had extremely high HR (171.6 +/- 20.5 beats/min, 168.1 +/- 9.8) continuously throughout the race. Though the ratio of active muscle mass of arms to legs in paraplegic athletes may approximate to near equal, paraplegic arms seem to exert physiologically and mechanically less efficient power. There were no significant differences in physical fitness between the full and the half marathon elite finishers. The cardiovascular function of paraplegic athletes may well be ranked among those of able-bodied athletes in their fitness. Full wheelchair marathon seems to be safe if it is held in an appropriate environment.

Adult↗
PubMed2005

Genetic isolation between two sympatric host plant races of the European corn borer, Ostrinia nubilalis Hubner. II: assortative mating and host-plant preferences for oviposition.

The European corn borer, Ostrinia nubilalis Hubner, colonized maize (Zea mays L.) after its introduction into Europe about 500 years ago and is now considered one of the main pests of this crop. In northern France, two sympatric host races have been described: one feeding on maize and the other on mugwort (Artemisia vulgaris L.) and hop (Humulus lupulus L.). In a previous study, we showed that mating between the two races may be impeded by differences in the timing of moth emergence and in the composition of the sex pheromone produced by the females. In this study, we further investigated the genetic isolation of these two races using strains from the maize (Z strain) and mugwort (E strain) races selected for diagnostic alleles at two allozyme loci. In a cage containing maize and mugwort plants and located in natural conditions, mating between individuals of the same strain occurred more often than mating between males and females of the E and Z strains. In particular, we obtained no evidence for crosses between Z females and E males. We also found that females of the Z strain laid their eggs almost exclusively on maize, whereas females of the E strain laid their eggs preferentially, but not exclusively, on mugwort. These results suggest that the genetic differentiation between the two host races may also be favored by host-plant preference, one of the first steps toward sympatric speciation.

Animals↗
PubMed2004

A new test to improve the training quality of wheelchair racing athletes.

STUDY DESIGN: Validation of a new wheelchair racing test. OBJECTIVE: To assess the reproducibility of test parameters at different, subjectively chosen, intensity levels in wheelchair racing athletes. SETTING: Swiss Paraplegic Centre, Nottwil, Switzerland. SUBJECTS: We tested 11 (eight male, three female) young competitive wheelchair racing athletes. Their age was 20.5+/-6.4 years, height 164.7+/-16.3 cm and weight 54.1+/-9.2 kg. Average weekly training time was 6.8+/-2.7 h. All had been engaged in regular training for over 3.9+/-2.8 years. METHODS: Within a period of 3+/-1 days, every athlete completed two identical tests in their own racing chair on a training roller. The tests consisted of five 1500 m bouts at routine training intensities of 1 (warm-up) up to 5 (race speed), with a rest of 2 min between each bout. The athletes were blinded to all the collected data during the whole of the test, except for indications of the 500, 1000 and 1500 m markers. We measured the overall time (for 1500 m), average speed, stroke frequency, heart rate, rate of perceived exertion (RPE) and the concentration of lactic acid for all five intensity bouts. In order to get a measure on how reproducible these intensity levels were, we compared the two tests of each athlete with each other, and calculated the root-mean-squared coefficients of variation (CV) for all measured parameters during every bout. RESULTS: CVs of the measured data show that the most reproducible values were found for bout 5 (2.6-7.9%); except for the lactic acid parameter. The heart rate (CV: 3.1-6.4%) and stroke frequency (CV: 6.5-7.9%) parameters reached rather constant values throughout all five bouts. Lactic acid concentrations showed very high CVs (16.8-29.7%). CONCLUSION: We conclude that this test is, with the exception of the lactic acid measurements, well reproducible, and particularly suitable for young wheelchair athletes. We find it to be a helpful tool for improving awareness for the individual training intensities, and for pursuing the development of the training process, as particularly the high-intensity bouts are well reproducible.

Adolescent↗
PubMed1997

Mild endotoxaemia and the inflammatory response induced by a marathon race.

1. To address the question of whether endotoxaemia could be involved in the inflammatory response induced by long-term strenuous exercise, 18 male marathon runners [mean age 41 +/- 2 (SEM) years] were studied. Their performance in the marathon ranged from 2 h 46 min to 4 h 42 min. 2. Four venous blood samples were drawn: at rest, just before the race (baseline); within 15 min following the completion of the marathon; after 1 h of recovery; and the morning after the race. 3. The following humoral markers of the inflammatory response to exercise were measured: polymorphonuclear myeloperoxidase (MPO), anaphylatoxin C5a (C5a), tumour necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6). Plasma endotoxin was measured by a sensitive and rapid chromogenic Limulus assay. All inflammatory markers were significantly increased (P < 0.001) after the race, reaching in most cases peak values in the first blood sample drawn following the completion of the marathon [MPO, 298 +/- 19 ng/ml (SEM); C5a, 1.45 +/- 0.32 ng/ml; TNF-alpha, 20 +/- 3 pg/ml; IL-6, 88 +/- 13 pg/ml] when compared with baseline [MPO, 146 +/- 16 ng/ml (SEM); C5a, 0.27 +/- 0.2 ng/ml; TNF-alpha, 12 +/- 1.5 pg/ml: IL-6, 1.0 +/- 0.5 pg/ml]. Traces of plasma endotoxin (ranging from 5 to 13 pg/ml, with one exceptionally high value of 72 pg/ml measured in one runner) were detected in seven subjects within the first hour of recovery. An ELISA method was used to determine the endogenous IgG antibodies toward a range of Gram-negative bacterial lipopolysaccharides (LPSs) of different sizes and structures. A transient decrease in certain anti-LPS activities, mainly against rough LPS, occurred in most cases in the first blood sample drawn after the race. There was no correlation between the magnitude of the inflammatory response to exercise, as assessed by the increase in blood levels of humoral markers of inflammation, and the changes in circulating endotoxin levels of anti-LPS IgG activity following the race. 4. From these results, we conclude that the mild, transient endotoxaemia detected in some of our subjects does not play a major role in the observed inflammatory response to a marathon competition.

Adult↗
PubMed2001

Chromosome races with Pliocene origins: evidence from mtDNA.

There are eight distinct chromosomal races of the New Zealand weta Hemideina thoracica. We used mtDNA sequence data to test the hypothesis that these races originated on islands during the early Pliocene (7--4 million years ago). Nine major mitochondrial lineages were identified from 65 cytochrome oxidase I sequences. Phylogenetic analysis of these lineages suggests that they arose at approximately the same time. The geographical distribution of some lineages coincides with areas that were islands during the Pliocene. Overall, hierarchical AMOVA analysis shows that chromosomal races and Pliocene islands describe only 28% and 24%, respectively, of the total current mtDNA variation. However, removing one widespread (A) and one putatively introgressed (F) lineage increases these estimates to 65% and 80%, respectively. Intraspecific sequence divergence was very high, reaching a maximum of 9.5% (uncorrected distance) and GC content was high compared to other insect mtDNA sequences. Average corrected distance among mtDNA lineages supports the Pliocene origins of this level of genetic diversity. In the southern part of the species range there is reduced mtDNA variation, probably related to local extinction of H. thoracica populations from recent volcanic activity and subsequent re-colonization from a leading edge. In contrast, in this southern part there are five chromosome races, suggesting that chromosome races here may be younger than those in the north.

Animals↗
PubMed2000

The importance of race in medical student performance of an AIDS risk assessment interview with simulated patients.

INTRODUCTION: This study was done to ascertain the effect of race on medical student-patient communication. The primary hypothesis was that interviewing performance scores would be higher when race of student and race of simulated patient instructor (SPI) were concordant than when they were discordant. METHODS: Data obtained from student interactions with four Caucasian and four African American female SPIs participating in a case involving an AIDS risk assessment interview were analysed. Performance was assessed using two instruments: an 8-item behaviourally anchored interviewing skills scale and a 14-item checklist reflecting content relevant to sexual behaviour and AIDS risk. SPI groups were comparable and SPIs were trained to a high level of inter-rater reliability. Students (24 African American and 180 non-African American) were assigned to SPIs based on the spelling of the student's name. Performance was scored independently at the conclusion of each interview by both the SPI and the student her/himself. RESULTS: African American students had lower scale scores than non-African American students in interactions with Caucasian (but not African American) SPIs; and all student scores, both on the skills scale and the content checklist, were higher with African American than with Caucasian SPIs (as assessed by both SPI and student). Women students had higher scores than men. CONCLUSIONS: Race of SPI has an influence on student performance of an AIDS risk assessment interview. Further studies focusing on racial interactions in the medical interview are required. It appears that race of SPI may need to be accounted for in the development and interpretation of SPI-based clinical competence exams.

Acquired Immunodeficiency Syndrome↗
PubMed2003

Edaphic races and phylogenetic taxa in the Lasthenia californica complex (Asteraceae: Heliantheae): an hypothesis of parallel evolution.

Lasthenia californica sensu Ornduff consists of two races that differ in their flavonoid pigments and edaphic tolerances. Recent phylogenetic studies of Lasthenia have revealed that members of L. californica sensu Ornduff belong to two phylogenetic species. The relationship of the edaphic races to these new species and to each other is the focus of this study. Characterization of flavonoid profiles and phylogenetic placement of 33 populations demonstrates that races and phylogenetic taxa are not concordant, suggesting that one or both edaphic races evolved in parallel in the two clades. We hypothesize an edaphically linked ecological role for flavonoid differences that first revealed the existence of two races.

Asteraceae↗
PubMed2000

The frequency of the detection of fetal echogenic intracardiac foci with respect to maternal race.

OBJECTIVE: To determine if there is a racial difference in the frequency of identification of echogenic intracardiac foci (EIF) seen sonographically in the hearts of second-trimester fetuses. METHODS: Over a 2-month period (June 1998-August 1998), all fetuses scanned between 15 and 20 completed weeks' gestation were evaluated prospectively for the presence or absence of EIF. Pregnancies specifically referred for the presence of EIF were excluded. The sonographer performing the scan indicated maternal race as Asian, black, white, or (if maternal race was not clear) unknown. Maternal race, gestational age, and the presence or absence of EIF were prospectively documented. Follow-up of those fetuses with EIF was obtained from the referring physicians' offices. The groups were compared with respect to maternal race and presence or absence of EIF. RESULTS: There were 46, 34, 400, and nine fetuses of the Asian, black, white, and unknown mothers, respectively. The mean gestational age +/- 1 SD at examination was 18.2 +/- 1.6, 17.5 +/- 1.4, 17.7 +/- 1.5, and 17.8 +/- 1.1 weeks, for the Asian, black, white, and unknown mothers, respectively. The incidence of sonographically detected EIF was 30.4, 5.9, 10.5 and 11.1% for the Asian, black, white, and unknown mothers, respectively, P = 0.001. In a multivariate logistic regression model, Asian mothers had an odds ratio of 3.8 (95% CI, 1.8, 7.6) for having a fetus identified as having EIF, as compared with white mothers. CONCLUSIONS: The Asian patient is more likely than patients of other races to have a fetus with identified EIF. The counseling implications for Asian mothers undergoing midtrimester sonography when EIF is identified should be tempered, due to the increased frequency of EIF as a normal finding in the Asian population.

Chi-Square Distribution↗
PubMed2002

Cytosolic ratio of malate dehyrogenase/lactate dehydrogenase activity in peripheral leukocytes of race horses with training.

The activities of the enzymes involved in the malate-aspartate shuttle and m RNA expression of malate dehydrogenase (MDH), a crucial enzyme for the NADH shuttle that produces ATP in glucose metabolism in the peripheral leukocytes of horses, were measured to investigate the change in metabolic states with training. There were no significant differences in plasma glucose and immunoreactive insulin concentrations between race horses and riding horses, used as a comparable reference. The cytosolic and mitochondrial MDH activities in leukocytes of race horses were significantly higher than those of riding horses. High activities of MDH in leukocytes of race horses were confirmed by RT - PCR analysis on the total RNA extracted from the whole blood. The cytosolic ratio of MDH /lactate dehydrogenase (LDH) activity (M/L ratio) in leukocytes of race horses was significantly higher than in those of riding horses. Increase in the M/L ratio was considered to reflect elevation of energy metabolism in animal tissues. The M/L ratio may be a useful parameter to evaluate the difference in metabolic states between race horses and riding horses.

Animals↗
PubMed1994

A comparison between aero and standard racing handlebars during prolonged exercise.

The use of aero style handlebars has gained popularity in triathlons and individual time trial events recently. The effect of using these handlebars has only been examined during short term exercise. It was the aim of this investigation to compare time to exhaustion and selected measures of ventilation, gas exchange and pulmonary function when using aero style handlebars versus standard racing style handlebars during long term exercise. Eleven well trained cyclists with a VO2max of 61.7 +/- 2.9 ml.kg-1.min-1 completed two continuous rides at 80 to 95 percent of their VO2max. Subjects rode at 80% of their VO2max for one hour and the work rate was increased by 5% of their VO2max every 15 min thereafter. The rides were completed with the subject riding his/her personal bicycle on a Velodyne trainer and differed in that during one ride the subjects rode with aero style handlebars and during the other they rode with standard racing style handlebars. During the ride with standard racing style handlebars, subjects rode with their hands on top of the bars or on the hoods of the brake levers. The subjects rode with the standard racing handlebars for 69.3 +/- 5.3 minutes as compared to 59.8 +/- 7.0 minutes with the aero style handlebars. This difference was not statistically significant. The average work rates when the cyclists terminated the exercise bouts with the aero and standard racing handlebars were 268.1 +/- 38.4 and 276.4 +/- 39.3 watts and were not significant from one another. Gas exchange and ventilatory parameters were measured every 15 min during the exercise bouts.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1997

No evidence of oxidative stress after a triathlon race in highly trained competitors.

Long distance triathlons, due to the large amounts of oxygen uptake they cause, may lead to the generation of reactive oxygen species, and consequently to oxidative stress and damage. We sought to verify this hypothesis. Twelve of the 18 male triathletes who participated in the study took part in a long distance triathlon, the others did not. The prerace blood samples were drawn 48 h before the race and repeatedly until the fourth day of recovery. The myoglobin concentrations increased immediately after the race. The concentrations of methemoglobin, disulfide glutathione (GSSG), and thiobarbituric reactive substances did not significantly change after the race. Although the race induced an inflammatory response, evidenced by the variations in neopterin concentrations and leukocyte counts, there was no consecutive oxidative stress. The basal GSH values were correlated significantly with cycling training volume (r = 0.55) and VO2max (r = 0.53). Muscle damage can occur without evidence of oxidative stress or oxidative damage. We conclude that the magnitude of the antioxidant defense system enhancement depends on training loads. Because of their training status, the triathletes did not suffer from oxidative damage after they finished the long distance triathlon race.

Adult↗
PubMed1996

An 'other-race effect' for categorizing faces by sex.

It is well-known that people recognize faces of their own race more accurately than faces of other races-a phenomenon often referred to as the 'other-race effect'. Using brief presentations of faces, we show a similar effect for the task of discriminating the sex of a face. Specifically, Caucasian observers discriminated male and female Caucasian faces more accurately/efficiently than did Oriental observers, and Oriental observers discriminated male and female Japanese faces more accurately/efficiently than did Caucasian observers. This result indicates that, under suboptimal viewing conditions, the identification of even the most salient of facial characteristics-face sex-is impaired for other-race faces. This finding suggests, also, that the nature and diversity of our experience with faces may affect not only the quality of the face representation for later access by recognition processes, but also the efficiency of a perceptual discrimination process. Intriguingly, too, we found that female observers, for both races tested, were considerably more accurate at the sex classification task than were male observers.

Adult↗
PubMed1982

Unique plasmid-like mitochondrial DNAs from indigenous maize races of Latin America.

Mitochondrial DNA from 81 races of Latin American maize were examined by agarose gel electrophoresis. Twelve South American races each contained two plasmid-like mtDNA molecules similar to those of the cytoplasmic male-sterile S type (cms-S). The plasmid-like elements from all 12 races, designated RU, appear to be identical. Both molecules appear in vitro as double-stranded linear DNAs terminated by repeated sequences arranged in reverse polarity (terminal inverted repeats). The larger molecule of the pair, R-1, contains about 7460 nucleotides. It shares considerable homology with the larger plasmid-like molecule of cms-S, S-1, but is about 1000 nucleotides longer than S-1, has a unique sequence of about 2576 nucleotides, and also contains a BamHI recognition site not present in S-1, R-2, the smaller plasmid-like element, consists of about 5450 nucleotides and appears to share complete homology with S-2, the smaller plasmid-like molecule of cms-S. Neither pollen sterility nor any other trait has been associated with the R-1 and R-2 plasmid-like mtDNAs. The BamHI restriction fragments of total mtDNA from the 12 RU cytoplasms display similar patterns, which differ only slightly but vividly from that of a normal maize standard, B73 x Mo17. BamHI restriction analysis of 22 additional races produced arrays similar to those of the RU cytoplasms, but which lacked plasmid-like mtDNAs. The taxonomic significance of this digestion pattern and of the RU cytoplasms is discussed. One Mexican race, Conico Norteño, has been shown to contain the cms-S cytoplasm.

Journal Article↗
PubMed1994

Rapid morphological radiation and convergence among races of the butterfly Heliconius erato inferred from patterns of mitochondrial DNA evolution.

The neotropical Heliconius butterflies are famous examples of Müllerian mimicry, due to the diverse array of shared, brightly colored wing patterns that advertise the butterflies' unpalatability. The parallel geographical variation in these patterns within several widespread species has been invoked to support the controversial Pleistocene refugium hypothesis of tropical diversification. However, in no Heliconius species have either evolutionary rates or relationships among geographical races been explicitly examined. I present a phylogenetic hypothesis based on mitochondrial DNA sequences for 14 divergent races of Heliconius erato, which reveals that similar wing patterns have evolved rapidly and convergently within the species. There is a basal split between groups of races from east and west of the Andes, reflecting a vicariant separation at the base of the Pleistocene. Within each of these clades, sequence divergence is very low, and some haplotypes are shared between allopatric races with radically different wing patterns. The topology implies a simultaneous radiation of races in these two areas within the last 200,000 years. Ages for the clades are estimated by comparing sequence divergence to a plot of mitochondrial divergence in several arthropod taxa with independently dated divergence times. This plot is linear and suggests that mitochondrial DNA in arthropods evolves in a clocklike manner, at least initially, when sequence divergence is low.

Animals↗
PubMed1997

Selective maintenance of allozyme differences among sympatric host races of the apple maggot fly.

Whether phytophagous insects can speciate in sympatry when they shift and adapt to new host plants is a controversial question. One essential requirement for sympatric speciation is that disruptive selection outweighs gene flow between insect populations using different host plants. Empirical support for host-related selection (i.e., fitness trade-offs) is scant, however. Here, we test for host-dependent selection acting on apple (Malus pumila)- and hawthorn (Crataegus spp.)-infesting races of Rhagoletis pomonella (Diptera: Tephritidae). In particular, we examine whether the earlier fruiting phenology of apple trees favors pupae in deeper states of diapause (or with slower metabolisms/development rates) in the apple fly race. By experimentally lengthening the time period preceding winter, we exposed hawthorn race pupae to environmental conditions typically faced by apple flies. This exposure induced a significant genetic response at six allozyme loci in surviving hawthorn fly adults toward allele frequencies found in the apple race. The sensitivity of hawthorn fly pupae to extended periods of warm weather therefore selects against hawthorn flies that infest apples and helps to maintain the genetic integrity of the apple race by counteracting gene flow from sympatric hawthorn populations. Our findings confirm that postzygotic reproductive isolation can evolve as a pleiotropic consequence of host-associated adaptation, a central tenet of nonallopatric speciation. They also suggest that one reason for the paucity of reported fitness trade-offs is a failure to consider adequately costs associated with coordinating an insect's life cycle with the phenology of its host plant.

Journal Article↗