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61.
James W. Pennebaker Cindy K. Chung Joey Frazee Gary M. Lavergne David I. Beaver 《PloS one》2014,9(12)
The smallest and most commonly used words in English are pronouns, articles, and other function words. Almost invisible to the reader or writer, function words can reveal ways people think and approach topics. A computerized text analysis of over 50,000 college admissions essays from more than 25,000 entering students found a coherent dimension of language use based on eight standard function word categories. The dimension, which reflected the degree students used categorical versus dynamic language, was analyzed to track college grades over students'' four years of college. Higher grades were associated with greater article and preposition use, indicating categorical language (i.e., references to complexly organized objects and concepts). Lower grades were associated with greater use of auxiliary verbs, pronouns, adverbs, conjunctions, and negations, indicating more dynamic language (i.e., personal narratives). The links between the categorical-dynamic index (CDI) and academic performance hint at the cognitive styles rewarded by higher education institutions. 相似文献
62.
- 1. 1. Scientists often use ambient temperature, relative humidity, or windspeed alone to describe an animal's thermal environment. Standard operative temperature (Tes) incorporates solar and thermal radiation, ambient temperature, and windspeed with a species' resistance to heat loss; thus it more accurately represents an animal's thermal environment. Standard operative temperature is not often recorded in the field because of instruments needed to measure short- and long-wave radiation.
- 2. 2. Our objective was to determine if regression equations could relate simple micrometeorological measurements to Tes for mule deer and cattle in winter.
- 3. 3. Blackglobe and ambient temperatures, windspeed, net radiation, total radiation, albedo, and ground surface temperature were recorded during one winter in a field in Bozeman, Montana. We used species specific resistance values for mule deer and cattle in winter to calculate Tes for both species. Then, we regressed Tes with blackglobe and ambient temperatures, and windspeed. The mule deer regression model was applied to an independent data set to determine if it worked well under varying weather conditions.
- 4. 4. The mule deer and cattle regression models represented Tes for both species well (adjusted R2 0.96 and 0.94, respectively). The mule deer regression model also represented the independent data set well. Standard operative temperatures predicted by our model and those predicted by the independent data set were highly correlated (r > 0.96 for four different comparisons). Our simple micrometeorological measurements are suitable predictors of Tes for mule deer and cattle in winter.
63.
Casaburi R.; Whipp B. J.; Wasserman K.; Beaver W. L.; Koyal S. N. 《Journal of applied physiology》1977,42(2):300-301
64.
ObjectivesRecent violent attacks on college campuses in the United States have sparked discussions regarding the prevalence of psychiatric disorders and the perpetration of violence among college students. While previous studies have examined the potential association between mental health problems and violent behavior, the overall pattern of findings flowing from this literature remain mixed and no previous studies have examined such associations among college students.MethodsThe current study makes use of a nationally representative sample of 3,929 college students from the National Epidemiologic Study on Alcohol and Related Conditions (NESARC) to examine the prevalence of seven violent behaviors and 19 psychiatric disorder diagnoses tapping mood, anxiety, personality, and substance use disorders. Associations between individual and composite psychiatric disorder diagnoses and violent behaviors were also examined. Additional analyses were adjusted for the comorbidity of multiple psychiatric diagnoses.ResultsThe results revealed that college students were less likely to have engaged in violent behavior relative to the non-student sample, but a substantial portion of college students had engaged in violent behavior. Age- and sex-standardized prevalence rates indicated that more than 21% of college students reported at least one violent act. In addition, more than 36% of college students had at least one diagnosable psychiatric disorder. Finally, the prevalence of one or more psychiatric disorders significantly increased the odds of violent behavior within the college student sample.ConclusionsThese findings indicate that violence and psychiatric disorders are prevalent on college campuses in the United States, though perhaps less so than in the general population. In addition, college students who have diagnosable psychiatric disorders are significantly more likely to engage in various forms of violent behavior. 相似文献
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Delay ER Beaver AJ Wagner KA Stapleton JR Harbaugh JO Catron KD Roper SD 《Chemical senses》2000,25(5):507-515
Monosodium glutamate (MSG) elicits a taste called umami and interacts synergistically with nucleotide monophosphates such as 5'-inosine monophosphate (IMP) to potentiate this taste intensity. Indeed, the synergistic interaction of nucleotide monophosphates and MSG is a hallmark of umami. We examined interactions between MSG and other taste stimuli, including IMP, by measuring the lick rates of non-deprived rats during 30 s trials. To control for non-linear psychophysical functions, the concentration of one taste stimulus in a binary mixture was systematically increased while the concentration of the second taste stimulus was decreased (stimulus substitution method). Synergy between two stimuli was detected if the lick rate for a binary mixture exceeded that expected from the sum of the lick rates for each stimulus alone. In initial experiments, taste synergy was observed when rats were presented with mixtures of MSG and IMP but not with mixtures of MSG and sucrose. In subsequent experiments, glutamate receptor agonists other than MSG were presented with IMP to test for taste synergy. No evidence of synergy was seen when rats were presented with mixtures of IMP and kainic acid or IMP and N:-methyl-D-aspartate. However, taste synergy between IMP and L-AP4, a potent agonist at mGluR4 receptors, was observed. These results suggest that a metabotropic glutamate receptor similar to mGluR4 may be involved in the taste synergy that characterizes umami. 相似文献
68.
Functional characterization of pathogenic human MSH2 missense mutations in Saccharomyces cerevisiae
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Hereditary nonpolyposis colorectal cancer (HNPCC) is associated with defects in DNA mismatch repair. Mutations in either hMSH2 or hMLH1 underlie the majority of HNPCC cases. Approximately 25% of annotated hMSH2 disease alleles are missense mutations, resulting in a single change out of 934 amino acids. We engineered 54 missense mutations in the cognate positions in yeast MSH2 and tested for function. Of the human alleles, 55% conferred strong defects, 8% displayed intermediate defects, and 38% showed no defects in mismatch repair assays. Fifty percent of the defective alleles resulted in decreased steady-state levels of the variant Msh2 protein, and 49% of the Msh2 variants lost crucial protein-protein interactions. Finally, nine positions are predicted to influence the mismatch recognition complex ATPase activity. In summary, the missense mutations leading to loss of mismatch repair defined important structure-function relationships and the molecular analysis revealed the nature of the deficiency for Msh2 variants expressed in the tumors. Of medical relevance are 15 human alleles annotated as pathogenic in public databases that conferred no obvious defects in mismatch repair assays. This analysis underscores the importance of functional characterization of missense alleles to ensure that they are the causative factor for disease. 相似文献
69.
Plankton biomass partitioning in a eutrophic subtropical lake: comparison with results from temperate lake ecosystems 总被引:1,自引:0,他引:1
Plankton were sampled for 6 years in a subtropical eutrophiclake in FL, USA, and absolute and relative carbon biomass wasdetermined for bacteria, phytoplankton, heterotrophic and phototrophicnanoflagellates, ciliates, rotifers and crustacean zooplankton.We compared the results with findings from a comprehensive studyof carbon biomass partitioning in eutrophic German lakes withelucidate common patterns and differences. Similarities betweenthe temperate and subtropical systems included: similar seasonaldynamics, with maximal carbon biomass of nanoflagellates andmetazoan zooplankton in spring and phytoplankton in summer toautumn, yearly averaged carbon occurring mainly in the phytoplanktonand phytoplankton accounting for a much greater proportion ofcarbon than bacteria. There also were differences: the Floridalake had lower absolute and relative carbon biomass in crustaceanzooplankton, stronger dominance of protozoa in total grazercarbon biomass, a lower ratio of zooplankton to phytoplanktoncarbon and almost a monoculture of predation-resistant copepods(versus a relatively balanced distribution of carbon among cladocerans,copepods and rotifers in the temperate lakes). The subtropicallake also had 4-fold higher relative biomass of small filamentouscyanobacteria in its phytoplankton, which we attribute to lightlimitation. Although the Florida and German studies did notmeasure biomass of planktivorous fish, the differences observedhere are consistent with a recent hypothesis that fish predationexerts stronger top–down control on the pelagic food webin subtropical lakes than in temperate lakes of similar trophicstatus. 相似文献
70.
Calder AJ Beaver JD Winston JS Dolan RJ Jenkins R Eger E Henson RN 《Current biology : CB》2007,17(1):20-25
Electrophysiological recording in the anterior superior temporal sulcus (STS) of monkeys has demonstrated separate cell populations responsive to direct and averted gaze. Human functional imaging has demonstrated posterior STS activation in gaze processing, particularly in coding the intentions conveyed by gaze, but to date has provided no evidence of dissociable coding of different gaze directions. Because the spatial resolution typical of group-based fMRI studies (approximately 6-10 mm) exceeds the size of cellular patches sensitive to different facial characteristics (1-4 mm in monkeys), a more sensitive technique may be required. We therefore used fMRI adaptation, which is considered to offer superior resolution, to investigate whether the human anterior STS contains representations of different gaze directions, as suggested by non-human primate research. Subjects viewed probe faces gazing left, directly ahead, or right. Adapting to leftward gaze produced a reduction in BOLD response to left relative to right (and direct) gaze probes in the anterior STS and inferior parietal cortex; rightward gaze adaptation produced a corresponding reduction to right gaze probes. Consistent with these findings, averted gaze in the adapted direction was misidentified as direct. Our study provides the first human evidence of dissociable neural systems for left and right gaze. 相似文献