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1.
The slow rate of mtDNA evolution in turtles poses a limitation on the levels of intraspecific variation detectable by conventional restriction fragment surveys. We examined mtDNA variation in the gopher tortoise (Gopherus polyphemus) using an alternative restriction assay, one in which PCR-amplified segments of the mitochondrial genome were digested with tetranucleotide-site endonucleases. Restriction fragment polymorphisms representing four amplified regions were analysed to evaluate population genetic structure among 112 tortoises throughout the species' range. Thirty-six haplotypes were identified, and three major geographical assemblages (Eastern, Western, and Mid-Florida) were resolved by UPGMA and parsimony analyses. Eastern and Western assemblages abut near the Apalachicola drainage, whereas the Mid-Florida assemblage appears restricted to the Brooksville Ridge. The Eastern/Western assemblage boundary is remarkably congruent with phylogeographic profiles for eight additional species from the south-eastern U.S., representing both freshwater and terrestrial realms. 相似文献
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Vibroarthrography (VAG) is an innovative, objective, non-invasive technique for obtaining diagnostic information concerning the articular cartilage of a joint. Knee VAG signals can be detected using a contact sensor over the skin surface of the knee joint during knee movement such as flexion and/or extension. These measured signals, however, contain significant interference caused by muscle contraction that is required for knee movement. Quality improvement of VAG signals is an important subject, and crucial in computer-aided diagnosis of cartilage pathology. While simple frequency domain high-pass (or band-pass) filtering could be used for minimizing muscle contraction interference (MCI), it could eliminate possible overlapping spectral components of the VAG signals. In this work, an adaptive MCI cancellation technique is presented as an alternative technique for filtering VAG signals. Methods of measuring the VAG and reference signals (MCI) are described, with details on MCI identification, characterization, and step size optimization for the adaptive filter. The performance of the method is evaluated by simulated signals as well as signals obtained from human subjects under isotonic contraction. 相似文献
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We have cloned and sequenced a cDNA encoding human cytoplasmic asparaginyl-tRNA synthetase (AsnRS). The N-terminal appended domain of 112 amino acid represents the signature sequence for the eukaryotic AsnRS and is absent from archaebacterial or eubacterial enzymes. The canonical ortholog for AsnRS is absent from most archaebacterial and some eubacterial genomes, indicating that in those organisms, formation of asparaginyl-tRNA is independent of the enzyme. The high degree of sequence conservation among asparaginyl- and aspartyl-tRNA synthetases (AsxRS) made it possible to infer the evolutionary paths of the two enzymes. The data show the neighbor relationship between AsnRS and eubacterial aspartyl-tRNA synthetase, and support the occurrence of AsnRS early in the course of evolution, which is in contrast to the proposed late occurrence of glutaminyl-tRNA synthetase. 相似文献
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YB Starikovskaya RI Sukernik TG Schurr AM Kogelnik DC Wallace 《Canadian Metallurgical Quarterly》1998,63(5):1473-1491
The mtDNAs of 145 individuals representing the aboriginal populations of Chukotka-the Chukchi and Siberian Eskimos-were subjected to RFLP analysis and control-region sequencing. This analysis showed that the core of the genetic makeup of the Chukchi and Siberian Eskimos consisted of three (A, C, and D) of the four primary mtDNA haplotype groups (haplogroups) (A-D) observed in Native Americans, with haplogroup A being the most prevalent in both Chukotkan populations. Two unique haplotypes belonging to haplogroup G (formerly called "other" mtDNAs) were also observed in a few Chukchi, and these have apparently been acquired through gene flow from adjacent Kamchatka, where haplogroup G is prevalent in the Koryak and Itel'men. In addition, a 16111C-->T transition appears to delineate an "American" enclave of haplogroup A mtDNAs in northeastern Siberia, whereas the 16192C-->T transition demarcates a "northern Pacific Rim" cluster within this haplogroup. Furthermore, the sequence-divergence estimates for haplogroups A, C, and D of Siberian and Native American populations indicate that the earliest inhabitants of Beringia possessed a limited number of founding mtDNA haplotypes and that the first humans expanded into the New World approximately 34,000 years before present (YBP). Subsequent migration 16,000-13,000 YBP apparently brought a restricted number of haplogroup B haplotypes to the Americas. For millennia, Beringia may have been the repository of the respective founding sequences that selectively penetrated into northern North America from western Alaska. 相似文献
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EC Greiner CL Mo EJ Homan J Gonzalez MT Oviedo LH Thompson EP Gibbs 《Canadian Metallurgical Quarterly》1993,7(4):309-315
Forty-four species of Culicoides (Diptera: Ceratopogonidae) were caught in insect light traps during the first 2 years of studies on the epidemiology of bluetongue virus in the Caribbean and Central America. Traps were operated near sentinel ruminants which were bled monthly for serologic evaluation and then virus isolation. More than 570,000 individuals were identified. Culicoides insignis Lutz accounted for 90% of the catch, C. filarifer Hoffman/C. ocumarensis Ortiz 5%, C. furens Poey 3% and C. pusillus Lutz 2%. Other species accounted for less than 1% of the total catch. Sentinel ruminants became seropositive when C. insignis populations were high at many study sites. At a few sites C. pusillus and C. filarifer/C. ocumarensis were predominant or were present in large numbers during seroconversions of sentinels. Virus isolations were obtained from sentinel ruminants during times when these same species were present in large populations. 相似文献
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I summarize a never-completed 1911 doctoral dissertation on ape behavior by Samuel Fernberger of the University of Pennsylvania. Included are observations on many behavioral patterns including sensory and perceptual function, learning, memory, attention, imagination, personality, and emotion in an orangutan and two chimpanzees. There are examples of behavior resembling insight, conscience, tool use and imitation. Language comprehension was good but speech production was minimal. The document appears to contradict a brief published article on the project by William Furness in that punishment was frequently used. The document is important for understanding Fernberger's early career, for anticipations of later research, and for understanding the status of ape research at the time. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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BL Duncan 《Canadian Metallurgical Quarterly》1976,34(4):590-598
In a modified 4 X 4 factorial design with race (black-white) of the harm-doer and race (black-white) of the victim as the major factors, the phenomenon of differential social perception of intergroup violence was established. While subjects, observing a videotape of purported ongoing ineraction occuring in another room, labeled an act (ambiguous shove) as more violent when it was performed by a black than when the same act was perpetrated by a white. That is, the concept of violence was more accessible when viewing a black than when viewing a white committing the same act. Causal attributions were also found to be divergent. Situation attributions were preferred when the harm-doer was white, and person (dispositional) attributions were preferred in the black-protagonist conditions. The results are discussed in terms of perceptual threshold, sterotypy, and attributional biases. 相似文献
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OBJECTIVES: To evaluate the clinical utility of transrectal ultrasound-guided systematic sextant needle biopsies in the prediction of extracapsular extension (ECE) at radical prostatectomy. METHODS: A retrospective analysis of 104 men who underwent systematic biopsy and radical prostatectomy at our institution was performed. All patients underwent preoperative staging by transrectal ultrasound and transrectal ultrasound-guided systematic sextant biopsy. The presence of pathologic ECE was correlated to the number of positive core biopsies on each side of the prostate by chi-square analysis. Sensitivity, specificity, positive and negative predictive values, and likelihood ratios (LRs) were calculated for both positive (two or three biopsies positive per side) and negative (no or one positive biopsy per side) test results. RESULTS: Forty-two (20.2%) of 208 sides demonstrated evidence of ECE at radical prostatectomy. Chi-square analysis demonstrated a significant correlation between the number of positive biopsies and the presence of ECE at radical prostatectomy (P = 0.001). Overall, the finding of multiple positive core biopsies (two or three per side) had predictive value with regard to the presence of ECE (sensitivity 62%, specificity 77%, positive predictive value 40%, negative predictive value 89%). The corresponding LRs were 2.5 for a positive and 0.5 for a negative test result. CONCLUSIONS: The probability of ECE at radical prostatectomy can be more accurately assessed preoperatively by the combined use of transrectal ultrasound and systematic sextant needle biopsies. 相似文献
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The focus of most studies in behavioral toxicology has been on effects of chemicals on learning and memory, sensory function, activity, and neuromuscular function. Behavior has also been used as a biomarker of chemical exposure, often without concern for the context in which the behavior was being observed. We have applied the strategies employed in ethological analyses of behavior and developed an alternative, ethotoxicological, approach to the study of effects of endocrine disruptors on behavior. This involves examining whether a behavioral alteration may be pathological from the perspective of the adaptive significance of the behavior under investigation. Pathological changes in behavior lead to reduced social adaptation and impaired responsiveness to environmental demands, with consequences for social structure and population dynamics. It thus follows that the ecological context in which the behavior would normally occur and the function of the behavior are of paramount importance when studying the impact of endocrine disruptors. 相似文献
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Objective personality testing began with Woodworth's Personal Data Sheet in 1917. That test was developed to identify soldiers prone to nervous breakdowns during enemy bombardment in World War I (WWI). Soon after, many competing personality tests were developed for use in industry. Many of these tests, like Woodworth's, focused on the construct of employee maladjustment and were deemed important in screening out applicants who would create workplace disturbances. In this article, the authors review the history of these early personality tests, especially the Bernreuter Personality Inventory and the Humm-Wadsworth Temperament Scale, and discuss the implications of personality testers' obsession with the construct of employee maladjustment. In addition, the authors discuss the industry's obsession with emotional maladjustment and how this obsession coincided with a cultural shift in norms relating to cultural expression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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With today's emphasis on Metrecal, dietary cola, and artificial sweeteners, one can only conclude that America is slenderness conscious. The low silhouettes of modern houses and factories, the soaring skyscrapers puncturing the horizon, reinforce the notion that sheer bulk is considered ugly nowadays. Our original aim in this study was to try to relate preferences for rectangle shapes to pleasing height/width architectural proportions. The golden rectangle has exercised a mystical mathematical appeal; the longer side is to the shorter as the shorter is to the difference between the sides. Cards were prepared showing a black rectangle, with the long side oriented vertically, on a white background. Two such packs were used, one having rectangles of equal width, the other rectangles of equal area. The 12 selected length/width ratios were identical for each pack ranging from 1/1 to 2.85/1, and the ratios included the golden rectangle. Subjects were given a pack of cards stacked in a random order and asked to spread them out, and then to choose the most pleasing shape. The main conclusion is that preferred height/width ratios for buildings are exceedingly variable. Second, there is a definite preference in favor of the tall and slender, much more so than for rectangles. In general it may be said that heights of Miss America pageant winners have been rather variable, waistlines have tended to become slimmer over the past 46 years, leading to an increasing height/waistline ratio. It is obvious that the height/waistline ratio cannot be a linear function of time; women were not wider than they were tall several hundred years ago. Yet one can look forward to slimmer waisted and perhaps slightly taller Miss America winners in the years to come. We therefore wish to affirm the notion that modern Americans are slenderness conscious. It can be stated that the golden rectangle is not now, and perhaps never was, a sure preference standard. But with each passing year it seems, to us at least, that the newest Miss America proves to be more shapely than ever. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Research in molecular genetics has led to the identification of a growing number of disease-predisposing genes. With increasing commercial pressures and public interest in genetic testing, genetic tests are likely to become an integral part of routine medical care. Awareness of genetic risk can facilitate informed medical decision making and, in some cases, can promote risk reduction behaviors that have the potential to reduce morbidity and mortality. Despite these potential medical benefits, there are serious concerns about the psychosocial sequelae of an individual learning that he or she carries an elevated risk for disease. This special issue of Health Psychology is devoted to research that seeks to provide an empirical foundation for the understanding of the psychosocial aspects of genetic testing for disease predisposition. The introduction to the special issue provides a brief overview of patterns of inheritance and genetic testing. This overview is followed by a consideration of the unique features of genetic information that make it different from other types of health threats studied by health psychologists. Finally, this author summarizes the organization of the issue, highlighting key study findings and suggesting future directions for this new field of research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Evolutionary psychologists explore the adaptive function of traits and behaviors that characterize modern Homo sapiens. However, evolutionary psychologists have yet to incorporate the phylogenetic relationship between modern Homo sapiens and humans’ hominid and pongid relatives (both living and extinct) into their theorizing. By considering the specific timing of evolutionary events and the role of evolutionary constraint, researchers using the phylogenetic approach can generate new predictions regarding mating phenomena and derive new explanations for existing evolutionary psychological findings. Especially useful is the concept of the adaptive workaround—an adaptation that manages the maladaptive elements of a pre-existing evolutionary constraint. The current review organizes 7 features of human mating into their phylogenetic context and presents evidence that 2 adaptive workarounds played a critical role as Homo sapiens’s mating psychology evolved. These adaptive workarounds function in part to mute or refocus the effects of older, previously evolved adaptations and highlight the layered nature of humans’ mating psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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EO Pelausa 《Canadian Metallurgical Quarterly》1997,26(5):345-350
OBJECTIVE: To evaluate changes in serial Acute Physiology and Chronic Health Evaluation (APACHE) II scores in patients with intrathoracic oesophageal anastomotic leaks and to assess their prognostic significance. DESIGN: Retrospective study. SETTING: Teaching hospital, Taiwan. SUBJECTS: 18 patients (4%) who developed intrathoracic oesophageal anastomotic leaks in a total of 491 patients who underwent oesophagogastrectomy for adenocarcinoma of the gastric cardia between 1980 and 1994. MAIN OUTCOME MEASURE: APACHE II scores in those that survived (n = 10) compared with those who died (n = 8). RESULTS: Of the 18 patients, 8 (44%) died. The preoperative general condition, biochemical data, and perioperative APACHE II scores were similar in the two groups. Leakage from the oesophageal anastomoses caused similar degrees of sepsis in the two groups in terms of APACHE II scoring, but the APACHE II scores of survivors started to decline within a week of initial management. In contrast, the APACHE II scores of those who died had increased one week after the leak had been diagnosed despite initial management. There were significant differences in the APACHE II scores of survivors and those who died from one week after leakage until discharge or death (p < 0.001). Only one patient (1/9) survived if the APACHE II score one week after diagnosis of the leak was more than 10. None died of the leak if the APACHE II scores were equal to or less than 10 after a week. CONCLUSIONS: Adequate surgical drainage, antibiotic cover according to the microbiological picture, and nutritional support are essential in the management of intrathoracic oesophageal fistulas. Early reoperation to close early leaks by simple suture or secondary wrapping and to improve local drainage is recommended. The APACHE II scoring system is valuable in evaluating the severity of sepsis caused by intrathoracic oesophagovisceral anastomosis leaks and may serve as an indicator of adequate management. Aggressive surgical measures should be considered if APACHE II scores rise during initial management. 相似文献
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Investigations of absenteeism: Using event history models to study the absence-taking process. 总被引:1,自引:0,他引:1
Traditional correlational and regression analyses of aggregated absences are ill-suited for estimating parameters of the absence-taking process. A class of event history models is described that effectively deals with the distributional and temporal properties of absences. One such model, a proportional hazard rate model, was applied to the daily attendance records of 2,130 incumbent, white-collar employees of a national financial service organization. Temporal and historical variables affected the hazard rate of voluntary absence taking. Demographic variables that were significantly correlated with aggregated absences did not improve prediction of the hazard rate. Consequences of violating the modeling assumptions of independent observations and large samples were examined empirically. Results indicated that the model was robust to such violations. Implications of the findings and of the successful application of the model are discussed. Several recommendations are made for using the model in organizations and for future studies of absence taking and other low base-rate events in organizations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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ES van Waalwijk van Doorn AH Meier AW Ambergen RA Janknegt 《Canadian Metallurgical Quarterly》1996,23(3):345-371
This article elucidates the clinical applicability and state of the art of ambulatory urodynamics. Ambulatory urodynamics have evolved into practical investigations like EAC, HFM, and EAC combined with renal pelvimetry. EAC has been shown to be the method of preference if detrusor overactivity is involved. Conventional filling cystometry has proved to be an unreliable way to exclude detrusor instability. De novo instability after suspension surgery often indicates that an existing detrusor overactivity was not identified preoperatively. EAC including flowmetry has shown considerable variance in obstructive and contractility parameters in males with LUTS indicative for BPH. This raises doubt whether the clinical flow analysis is the suitable "gold standard" as advocated by the ICS. For a real break through of EAC, less complex automatic analysis is necessary. HFM is a newer method within the range of ambulatory urodynamic tests. It has not yet been completely evaluated. But, because the technique is analogous to the office flowmetry, noninvasive and very well accepted by the patients, it is expected to be widely used. This expectation is strengthened by the fact that HFM seems to show individual therapeutic efficacy of drugs, such as alpha-blockers. As a research tool to evaluate efficacy, it is far more powerful than conventional methods because of the reduction of within-patient standard deviation to about 10%. Finally, EAC combined with pelvimetry offers a promising method for the clinical evaluation of a combined dysfunction of upper and lower urinary tract. 相似文献
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This special issue is intended to provide professionals and other members of the policy-shaping community with information from which judgments concerning the appropriate role of IQ testing in the delivery of school psychological services can be formed. In Kaufman's (1994) most recent rendition of his intelligent testing series, Intelligent testing with the WISC-III, he devotes a major section of the first chapter to his presumed defense of IQ testing against criticisms that have emerged within the school psychology literature. Are the inferences derived by Kaufman's methods of WISC-III test interpretation of sufficient quality to support their use in professional problem solving and decision making? Are they reliable? Are they accurate? Do they contribute to beneficial outcomes for children? These are guiding questions that represent underlying themes for this special issue. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献