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1.
Proc Natl Acad Sci U S A ; 114(45): 12009-12014, 2017 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-29078324

RESUMO

Cladoxylopsida included the earliest large trees that formed critical components of globally transformative pioneering forest ecosystems in the Mid- and early Late Devonian (ca. 393-372 Ma). Well-known cladoxylopsid fossils include the up to ∼1-m-diameter sandstone casts known as Eospermatopteris from Middle Devonian strata of New York State. Cladoxylopsid trunk structure comprised a more-or-less distinct cylinder of numerous separate cauline xylem strands connected internally with a network of medullary xylem strands and, near the base, externally with downward-growing roots, all embedded within parenchyma. However, the means by which this complex vascular system was able to grow to a large diameter is unknown. We demonstrate-based on exceptional, up to ∼70-cm-diameter silicified fossil trunks with extensive preservation of cellular anatomy from the early Late Devonian (Frasnian, ca. 374 Ma) of Xinjiang, China-that trunk expansion is associated with a cylindrical zone of diffuse secondary growth within ground and cortical parenchyma and with production of a large amount of wood containing both rays and growth increments concentrically around individual xylem strands by normal cambia. The xylem system accommodates expansion by tearing of individual strand interconnections during secondary development. This mode of growth seems indeterminate, capable of producing trees of large size and, despite some unique features, invites comparison with secondary development in some living monocots. Understanding the structure and growth of cladoxylopsids informs analysis of canopy competition within early forests with the potential to drive global processes.


Assuntos
Árvores/crescimento & desenvolvimento , Evolução Biológica , China , Planeta Terra , Ecossistema , Florestas , Fósseis , New York , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Árvores/metabolismo , Madeira/crescimento & desenvolvimento , Madeira/metabolismo , Xilema/metabolismo
2.
Proc Natl Acad Sci U S A ; 113(24): 6695-700, 2016 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-27226309

RESUMO

Lycophyte trees, up to 50 m in height, were the tallest in the Carboniferous coal swamp forests. The similarity in their shoot and root morphology led to the hypothesis that their rooting (stigmarian) systems were modified leafy shoot systems, distinct from the roots of all other plants. Each consists of a branching main axis covered on all sides by lateral structures in a phyllotactic arrangement; unbranched microphylls developed from shoot axes, and largely unbranched stigmarian rootlets developed from rhizomorphs axes. Here, we reexamined the morphology of extinct stigmarian systems preserved as compression fossils and in coal balls from the Carboniferous period. Contrary to the long-standing view of stigmarian systems, where shoot-like rhizomorph axes developed largely unbranched, root-hairless rootlets, here we report that stigmarian rootlets were highly branched, developed at a density of ∼25,600 terminal rootlets per meter of rhizomorph, and were covered in root hairs. Furthermore, we show that this architecture is conserved among their only extant relatives, herbaceous plants in the Isoetes genus. Therefore, despite the difference in stature and the time that has elapsed, we conclude that both extant and extinct rhizomorphic lycopsids have the same rootlet system architecture.


Assuntos
Brotos de Planta/fisiologia , Rizoma/fisiologia , Árvores/fisiologia , Brotos de Planta/anatomia & histologia , Rizoma/anatomia & histologia , Árvores/anatomia & histologia
3.
Nature ; 483(7387): 78-81, 2012 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-22382983

RESUMO

The origin of trees by the mid-Devonian epoch (398-385 million years ago) signals a major change in terrestrial ecosystems with potential long-term consequences including increased weathering, drop in atmospheric CO(2), modified climate, changes in sedimentation patterns and mass extinction. However, little is known about the ecology of early forests or how changes in early terrestrial ecosystems influenced global processes. One of the most famous palaeontological records for this time is the 'oldest fossil forest' at Riverside Quarry, Gilboa, New York, USA, discovered in the 1920s. Hundreds of large Eospermatopteris sandstone casts, now thought to represent the bases of standing cladoxylopsid trees, were recovered from a horizon that was originally interpreted as a muddy swamp. After quarry operations ceased, relatively minor outcrops of similar fossils at nearby localities have provided limited opportunities to evaluate this pervasive view using modern methods. In 2010, removal of the quarry backfill enabled reappraisal of the palaeoecology of this important site. Here we describe a 1,200 m(2) map showing numerous Eospermatopteris root systems in life position within a mixed-age stand of trees. Unexpectedly, large woody rhizomes with adventitious roots and aerial branch systems identified as aneurophytalean progymnosperms run between, and probably climb into, Eospermatopteris trees. We describe the overall habit for these surprisingly large aneurophytaleans, the earliest fossil group having wood produced by a bifacial vascular cambium. The site also provides evidence for arborescence within lycopsids, extending the North American range for trees in this ecologically critical group. The rooting horizon is a dark grey sandy mudstone showing limited root penetration. Although clearly belonging to a wetland coastal plain environment, the forest was probably limited in duration and subject to periodic disturbance. These observations provide fundamental clarification of the palaeoecology of this mixed-group early forest, with important implications for interpreting coeval assemblage data worldwide.


Assuntos
Biodiversidade , Fósseis , Árvores/fisiologia , Câmbio/metabolismo , Indústrias Extrativas e de Processamento , New York , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/fisiologia , Rizoma/anatomia & histologia , Rizoma/fisiologia , Solo/análise , Solo/química , Árvores/anatomia & histologia , Áreas Alagadas , Madeira/metabolismo
4.
Multivariate Behav Res ; 52(2): 164-177, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27997223

RESUMO

A common form of missing data is caused by selection on an observed variable (e.g., Z). If the selection variable was measured and is available, the data are regarded as missing at random (MAR). Selection biases correlation, reliability, and effect size estimates when these estimates are computed on listwise deleted (LD) data sets. On the other hand, maximum likelihood (ML) estimates are generally unbiased and outperform LD in most situations, at least when the data are MAR. The exception is when we estimate the partial correlation. In this situation, LD estimates are unbiased when the cause of missingness is partialled out. In other words, there is no advantage of ML estimates over LD estimates in this situation. We demonstrate that under a MAR condition, even ML estimates may become biased, depending on how partial correlations are computed. Finally, we conclude with recommendations about how future researchers might estimate partial correlations even when the cause of missingness is unknown and, perhaps, unknowable.


Assuntos
Interpretação Estatística de Dados , Funções Verossimilhança , Análise Multivariada , Algoritmos , Simulação por Computador , Escolaridade , Humanos , Método de Monte Carlo , Reprodutibilidade dos Testes , Fatores Socioeconômicos , Estudantes , Universidades
5.
J Pers ; 83(1): 14-25, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24219574

RESUMO

This study investigates the personality processes involved in the debate surrounding the use of cognitive ability tests in college admissions. In Study 1, 108 undergraduates (Mage = 18.88 years, 60 women, 80 Whites) completed measures of social dominance orientation (SDO), testing self-efficacy, and attitudes regarding the use of cognitive ability tests in college admissions; SAT/ACT scores were collected from the registrar. Sixty-seven undergraduates (Mage = 19.06 years, 39 women, 49 Whites) completed the same measures in Study 2, along with measures of endorsement of commonly presented arguments about test use. In Study 3, 321 American adults (Mage = 35.58 years, 180 women, 251 Whites) completed the same measures used in Study 2; half were provided with facts about race and validity issues surrounding cognitive ability tests. Individual differences in SDO significantly predicted support for the use of cognitive ability tests in all samples, after controlling for SAT/ACT scores and test self-efficacy and also among participants who read facts about cognitive ability tests. Moreover, arguments for and against test use mediated this effect. The present study sheds new light on an old debate by demonstrating that individual differences in beliefs about hierarchy play a key role in attitudes toward cognitive ability test use.


Assuntos
Atitude , Teste de Admissão Acadêmica , Testes de Inteligência , Predomínio Social , Adolescente , Adulto , Cognição , Cultura , Etnicidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Racismo , Autoeficácia , Estudantes , Universidades , Adulto Jovem
6.
Curr Opin Psychol ; 60: 101905, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39317117

RESUMO

Personnel selection systems affect diversity because they are the way organizations choose who is hired. Research on personnel selection systems and diversity is reviewed, with a particular focus on racial/ethnic diversity. Topics covered include the interrelated concepts of adverse impact and subgroup mean differences, research on why mean differences exist, and which selection predictors (particularly, cognitive ability tests) are most likely to cause adverse impact due to these mean differences. The historical perspective that organizations face a dilemma due to cognitive ability tests having the greatest validity and largest racial/ethnic subgroup mean differences is reviewed. Additionally, recent research is covered that suggests the validity of cognitive ability tests has been substantially overestimated, which has significant implications for the "validity-diversity dilemma."

7.
J Appl Psychol ; 109(3): 362-385, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37843545

RESUMO

To date, the unethical pro-organizational behavior (UPB) literature has been guided by a prosocial perspective, which argues that people engage in UPB primarily to benefit the employers with whom they identify and have a positive social exchange. According to this perspective, employees who are characteristically self-interested are less likely to engage in UPB. However, recent evidence suggests self-interest may play a larger role in motivating UPB than originally theorized. To clarify this controversy, we offer two different, but not necessarily mutually exclusive, perspectives of UPB-one in which UPB is driven primarily by prosocial motives and one in which it is driven primarily by self-interest. We tested which of these accounts of UPB was more strongly supported by comparing UPB's relationships with two nomological networks: one containing relatively prosocially motivated constructs and the other containing relatively self-interest-motivated constructs. Two of the eight hypotheses from the prosocial perspective were supported, while seven of the eight hypotheses from the self-interest perspective were supported. Additionally, the average absolute value of UPB's correlations with prosocial perspective constructs was .09, while the comparable average correlation with self-interest perspective constructs was .33. Thus, the results favored the self-interest perspective. We discuss how these findings change our theoretical understanding of UPB by acknowledging both its prosocial and self-interest motivations, and we accordingly propose a revised definition for UPB that allows for both of these motivations. We also examined more broadly the relationship between UPB and other constructs to provide a comprehensive meta-analytic overview of this literature. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Motivação , Comportamento Social , Humanos , Metanálise em Rede
8.
J Appl Psychol ; 109(10): 1611-1634, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38695805

RESUMO

General mental ability (GMA) tests have long been at the heart of the validity-diversity trade-off, with conventional wisdom being that reducing their weight in personnel selection can improve adverse impact, but that this results in steep costs to criterion-related validity. However, Sackett et al. (2022) revealed that the criterion-related validity of GMA tests has been considerably overestimated due to inappropriate range restriction corrections. Thus, we revisit the role of GMA tests in the validity-diversity trade-off using an updated meta-analytic correlation matrix of the relationships six selection methods (biodata, GMA tests, conscientiousness tests, structured interviews, integrity tests, and situational judgment tests) have with job performance, along with their Black-White mean differences. Our results lead to the conclusion that excluding GMA tests generally has little to no effect on validity, but substantially decreases adverse impact. Contrary to popular belief, GMA tests are not a driving factor in the validity-diversity trade-off. This does not fully resolve the validity-diversity trade-off, though: Our results show there is still some validity reduction required to get to an adverse impact ratio of .80, although the validity reduction is less than previously thought. Instead, it shows that the validity-diversity trade-off conversation should shift from the role of GMA tests to that of other selection methods. The present study also addresses which selection methods now emerge as most valid and whether composites of selection methods can result in validities similar to those expected prior to Sackett et al. (2022). (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Seleção de Pessoal , Humanos , Seleção de Pessoal/normas , Reprodutibilidade dos Testes , Testes de Aptidão/normas , Aptidão/fisiologia
9.
Nature ; 446(7138): 904-7, 2007 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-17443185

RESUMO

The evolution of trees of modern size growing together in forests fundamentally changed terrestrial ecosystems. The oldest trees are often thought to be of latest Devonian age (about 380-360 Myr old) as indicated by the widespread occurrence of Archaeopteris (Progymnospermopsida). Late Middle Devonian fossil tree stumps, rooted and still in life position, discovered in the 1870s from Gilboa, New York, and later named Eospermatopteris, are widely cited as evidence of the Earth's 'oldest forest'. However, their affinities and significance have proved to be elusive because the aerial portion of the plant has been unknown until now. Here we report spectacular specimens from Schoharie County, New York, showing an intact crown belonging to the cladoxylopsid Wattieza (Pseudosporochnales) and its attachment to Eospermatopteris trunk and base. This evidence allows the reconstruction of a tall (at least 8 m), tree-fern-like plant with a trunk bearing large branches in longitudinal ranks. The branches were probably abscised as frond-like modules. Lower portions of the trunk show longitudinal carbonaceous strands typical of Eospermatopteris, and a flat bottom with many small anchoring roots. These specimens provide new insight into Earth's earliest trees and forest ecosystems. The tree-fern-like morphology described here is the oldest example so far of an evolutionarily recurrent arborescent body plan within vascular plants. Given their modular construction, these plants probably produced abundant litter, indicating the potential for significant terrestrial carbon accumulation and a detritus-based arthropod fauna by the Middle Devonian period.


Assuntos
Evolução Biológica , Fósseis , Árvores/anatomia & histologia , Árvores/fisiologia , Tamanho Corporal , Ecossistema , História do Século XIX , História Antiga , New York , Fatores de Tempo , Árvores/classificação
10.
J Pers Soc Psychol ; 124(2): 413-436, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35980691

RESUMO

Social dominance orientation (SDO) holds a central position in social dominance theory. Since the development, validation, and publication of the SDO7 scale in 2015, which was designed to distinguish between the dominance (SDO-D) and (anti-)egalitarianism (SDO-E) facets of SDO, it has become common in the literature to distinguish between these facets using the SDO7. This is based on the theoretical proposition that SDO-D and SDO-E meaningfully differ and have different relationships with other constructs. However, the present study critically reviews the original validity evidence provided for the SDO7's distinction between SDO-D and SDO-E and notes conceptual and empirical reasons to question this distinction. Because a sizable number of studies have used the SDO7 since the presentation of that original validity evidence, the present study uses meta-analysis to leverage this burgeoning literature to determine whether there has since been more convincing empirical evidence for the distinction between these facets. The meta-analysis finds that SDO-D and SDO-E have a magnitude of intercorrelation that would often be considered adequate for a reliability coefficient (mean ρ = .83), have extremely similar patterns and magnitudes of relationships with the variables in their nomological network, and have nearly identical means and standard deviations. Although the SDO7 is a useful, reliable, and valid measure of overall SDO, its use to distinguish between SDO-D and SDO-E is not empirically supported. The present meta-analysis also provides insights into the nomological network of SDO-D, SDO-E, and overall SDO and the distributional characteristics of study participants' SDO scale scores. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Predomínio Social , Humanos , Reprodutibilidade dos Testes
11.
J Appl Psychol ; 108(2): 291-306, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36108044

RESUMO

Much attention has been paid to the question of whether there is a modesty bias in East Asian employees' self-ratings of job performance (i.e., a tendency to self-rate their performance lower than supervisors rate it). However, empirical results are conflicting, with some studies supporting the modesty bias and others not supporting it. We suggest that moderators representing boundary conditions for the modesty bias effect may shed light on these conflicting results. In essence, the question should not be "whether there is a modesty bias," but rather "when is there a modesty bias?" We propose three moderators: purpose of the ratings (administrative, developmental, or research), job performance dimension (task performance, organizational citizenship behavior, or leadership), and country-level in-group collectivism. Based on 40 studies (63 independent samples) with samples from East Asia (mainland China, Japan, South Korea, and Taiwan), we found no evidence of a modesty bias. That is, East Asian employees' self-ratings were, on average, higher than supervisor-ratings of job performance (i.e., a leniency bias). The one exception was when ratings were collected for research purposes; in this case, there was, on average, no mean difference between self- and supervisor-ratings. Thus, East Asian employees' research-purpose self-ratings are more modest, but this does not cross into a "modesty bias." In all, our results do not support a modesty bias as a widespread cultural norm among East Asian employees. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Desempenho Profissional , Humanos , População do Leste Asiático , Liderança , Salários e Benefícios , China
12.
J Appl Psychol ; 108(2): 341-349, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34735177

RESUMO

Berry et al. (2020) noted that predictive bias is a function of three factors: subgroup mean difference on the predictor (dx), subgroup mean difference on the criterion (dy), and test validity (rxy). They used meta-analytic estimates of each of these three to examine predictive bias against Hispanic test takers when cognitive tests are used in personnel selection. They found that tests underpredict Hispanic job performance by an average of .21 SDs, which would call into question the fairness of cognitive test use in personnel selection. We located 119 studies in which all three parameters-dy, dx, and rxy-could be obtained, thus holding sample, setting, and operationalization constant in estimating the three parameters within each study. This produced a substantially different conclusion: We find that tests overpredict Hispanic performance by .04-.20 SDs, depending on assumptions made about artifact corrections. Factors contributing to differences between the two studies include differences in range restriction corrections, sample incomparability, and Berry et al.'s use of rxy estimated from the total sample rather than within the majority subgroup. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Seleção de Pessoal , Desempenho Profissional , Humanos , Testes de Aptidão , Hispânico ou Latino , Projetos de Pesquisa
13.
J Appl Psychol ; 108(8): 1311-1315, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37498723

RESUMO

Oh et al. (2023) question a number of choices made in our article (Sackett et al., 2022); here we respond. They interpret our article as recommending against correcting for range restriction in general in concurrent validation studies; yet, we emphasize that we endorse correction when one has access to the information needed to do so. Our focus was on making range restriction corrections when conducting meta-analyses, where it is common for primary studies to be silent as to the prior basis for selection of the employees later participating in the concurrent validation study. As such, the applicant pool information needed for correction is typically not available. Sackett et al. (2022) highlighted that in many situations, range restriction will be small; so, the inability to correct for it results in only a modest underestimate of validity. Oh et al. mention settings that would result in substantial range restriction; here, we present our rationale as to why we view such settings as uncommon rather than as making up the bulk of the studies contributing to meta-analyses. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

14.
J Appl Psychol ; 108(1): 167-178, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35482665

RESUMO

Due to well-known problems with self-ratings of job performance (e.g., inflation, weak correlation with supervisor ratings) and the challenges of collecting supervisor ratings of job performance, researchers sometimes use supervisor-perspective ratings (e.g., "how do you think your supervisor would rate your job performance?") instead. The assumption is supervisor-perspective ratings are less affected by the noted issues with self-ratings and therefore are more similar to actual supervisor ratings than traditional self-ratings. In fact, a considerable number of researchers have used supervisor-perspective ratings as an alternative to actual supervisor ratings. The purpose of this study is to meta-analytically determine the degree to which supervisor-perspective ratings are a valid substitute for actual supervisor ratings and identify the boundary conditions for this substitution. Our meta-analyses demonstrate that supervisor-perspective ratings are generally not a viable substitute for actual supervisor ratings. This is especially the case when (a) citizenship performance is measured, (b) data are collected in collectivistic cultures, and (c) all study data are gathered from the same source. We recommend not using supervisor-perspective ratings as a substitute for actual supervisor ratings. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Desempenho Profissional , Humanos
15.
J Appl Psychol ; 107(11): 2040-2068, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34968080

RESUMO

This paper systematically revisits prior meta-analytic conclusions about the criterion-related validity of personnel selection procedures, and particularly the effect of range restriction corrections on those validity estimates. Corrections for range restriction in meta-analyses of predictor-criterion relationships in personnel selection contexts typically involve the use of an artifact distribution. After outlining and critiquing five approaches that have commonly been used to create and apply range restriction artifact distributions, we conclude that each has significant issues that often result in substantial overcorrection and that therefore the validity of many selection procedures for predicting job performance has been substantially overestimated. Revisiting prior meta-analytic conclusions produces revised validity estimates. Key findings are that most of the same selection procedures that ranked high in prior summaries remain high in rank, but with mean validity estimates reduced by .10-.20 points. Structured interviews emerged as the top-ranked selection procedure. We also pair validity estimates with information about mean Black-White subgroup differences per selection procedure, providing information about validity-diversity tradeoffs. We conclude that our selection procedures remain useful, but selection predictor-criterion relationships are considerably lower than previously thought. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Assuntos
Seleção de Pessoal , Desempenho Profissional , Humanos , Seleção de Pessoal/métodos , Ocupações
16.
Nat Plants ; 8(2): 104-109, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35115726

RESUMO

The latitudinal biodiversity gradient, with tropical regions acting as 'evolutionary cradles', is a cornerstone of current biogeographical and ecological theory1. In the modern world floral biodiversity and biomass are overwhelmingly concentrated in the tropics, and it is often assumed that the tropics were evolutionary cradles throughout land plant evolutionary history. For example, the origination and diversification of angiosperms is believed to have taken place in the Cretaceous tropics2 and modern gymnosperms in the Permian tropics3. Here, we show that during the first major diversification of land plants, in the Late Silurian-Early Devonian, land plant biodiversity was much lower at the equator compared to medium-high southern latitudes. Throughout this crucial interval of plant evolution, tropical vegetation remained depauperate and of very low taxonomic biodiversity, although with similar morphological disparity to the more diverse higher latitude floras. Possible explanations for this low tropical floral biodiversity include palaeocontinental configuration or adverse palaeotropical environmental conditions. We discount the possibility that it was simply a fortuitous feature of the biogeographical spread of the earliest vascular land plants.


Assuntos
Magnoliopsida , Clima Tropical , Biodiversidade , Evolução Biológica , Cycadopsida , Filogenia
17.
Am J Hypertens ; 34(6): 619-625, 2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-33693473

RESUMO

BACKGROUND: Obesity and hypertension are public health priorities, with obesity considered to be a potential cause of hypertension. Accurate blood pressure (BP) determination is required and often obtained by automated oscillometric cuff devices. We sought to determine the correlation of oscillometric measurement in children, and if obesity was associated with worse correlation between methods than nonobese children. METHODS: Retrospective matched case-controlled study of 100 obese (97-99th percentile) and 100 nonobese (25-70th percentile) children after cardiac surgery with simultaneous systolic, diastolic, and mean invasive and oscillometric measurements. Matching was 1:1 for age, sex, race, and Risk Adjustment for Congenital Heart Surgery-1 score. Intraclass correlation coefficients and Bland-Altman plots were used to determine agreement with 0.75 as threshold. RESULTS: Median age was 13 years (10-15). Agreement was low for systolic (0.65 and 0.61), diastolic (0.68 and 0.61), and mean measurements (0.73 and 0.69) (obese/nonobese). Bland-Altman plots demonstrated oscillometric BP measurements underestimated systolic hypertension (oscillometric readings lower than intra-arterial). Oscillometric measurements underestimated hypotension (systolic oscillometric measurements were higher than intra-arterial). This occurred in obese and nonobese patients. Correlation of oscillometric measurements was similar for nonobese and obese patients. CONCLUSIONS: In this first ever study of simultaneous BP measurement by oscillometric vs. intra-arterial in obese and nonobese children, correlation is below accepted norms. The correlation of oscillometric cuff measurements is not affected by habitus in children. There is less correlation between oscillometric measurements and intra-arterial measurements during hypertension or hypotension. Healthcare providers should be aware of the limitations of oscillometric measurements.


Assuntos
Determinação da Pressão Arterial , Obesidade Infantil , Adolescente , Determinação da Pressão Arterial/métodos , Criança , Feminino , Humanos , Masculino , Oscilometria , Obesidade Infantil/epidemiologia , Reprodutibilidade dos Testes , Estudos Retrospectivos
18.
Nat Plants ; 6(5): 454-459, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32366983

RESUMO

Roots of extant vascular plants proliferate through lateral branching (euphyllophytes) or dichotomy (lycophytes)1-4. The origin of these distinct modes of branching was key for plant evolution because they enabled the development of structurally and functionally different root systems that supported a diversity of shoot systems3-6. It has been unclear when lateral branching originated and how many times it evolved4,7,8. Here, we report that many euphyllophytes that were extant during the Devonian and Carboniferous periods developed dichotomous roots. Our data indicate that dichotomous root branching evolved in both lycophytes and euphyllophytes. Lateral roots then evolved at different times in three major lineages of extant euphyllophytes-the lignophytes, ferns and horsetails. The multiple origins of dichotomous and lateral root branching are extreme cases of convergent evolution that occurred during the Devonian and Carboniferous periods when the land-plant flora underwent a radiation in morphological diversity.


Assuntos
Evolução Biológica , Raízes de Plantas/crescimento & desenvolvimento , Fósseis , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/fisiologia
19.
Curr Biol ; 30(3): 421-431.e2, 2020 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-31866369

RESUMO

The origin of trees and forests in the Mid Devonian (393-383 Ma) was a turning point in Earth history, marking permanent changes to terrestrial ecology, geochemical cycles, atmospheric CO2 levels, and climate. However, how all these factors interrelate remains largely unknown. From a fossil soil (palaeosol) in the Catskill region near Cairo NY, USA, we report evidence of the oldest forest (mid Givetian) yet identified worldwide. Similar to the famous site at Gilboa, NY, we find treefern-like Eospermatopteris (Cladoxylopsida). However, the environment at Cairo appears to have been periodically drier. Along with a single enigmatic root system potentially belonging to a very early rhizomorphic lycopsid, we see spectacularly extensive root systems here assigned to the lignophyte group containing the genus Archaeopteris. This group appears pivotal to the subsequent evolutionary history of forests due to possession of multiple advanced features and likely relationship to subsequently dominant seed plants. Here we show that Archaeopteris had a highly advanced root system essentially comparable to modern seed plants. This suggests a unique ecological role for the group involving greatly expanded energy and resource utilization, with consequent influence on global processes much greater than expected from tree size or rooting depth alone.


Assuntos
Evolução Biológica , Embriófitas/anatomia & histologia , Fósseis/anatomia & histologia , Árvores/anatomia & histologia , Embriófitas/fisiologia , New York , Árvores/fisiologia
20.
Psychol Sci ; 20(7): 822-30, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19493326

RESUMO

We demonstrate that the validity of SAT scores and high school grade point averages (GPAs) as predictors of academic performance has been underestimated because of previous studies' reliance on flawed performance indicators (i.e., college GPA) that are contaminated by the effects of individual differences in course choice. We controlled for this contamination by predicting individual course grades, instead of GPAs, in a data set containing more than 5 million college grades for 167,816 students. Percentage of variance accounted for by SAT scores and high school GPAs was 30 to 40% lower when the criteria were freshman and cumulative GPAs than when the criteria were individual course grades. SAT scores and high school GPAs together accounted for between 44 and 62% of the variance in college grades. This study provides new estimates of the criterion-related validity of SAT scores and high school GPAs, and highlights the care that must be taken in choosing appropriate criteria in validity studies.


Assuntos
Comportamento de Escolha/fisiologia , Teste de Admissão Acadêmica/estatística & dados numéricos , Currículo/estatística & dados numéricos , Critérios de Admissão Escolar/estatística & dados numéricos , Universidades/estatística & dados numéricos , Escolha da Profissão , Currículo/normas , Escolaridade , Humanos , Reprodutibilidade dos Testes , Estudantes/psicologia
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