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1.
R Soc Open Sci ; 7(4): 200277, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32431909

RESUMO

Insect wing shapes and the internal wing-vein arrangement are remarkably diverse. Although the wings lack intrinsic musculature to adjust shape actively, they elastically deform due to aerodynamic and inertial loads during flapping. In turn, the deformations alter the shape of the wing profile affecting the aerodynamic force. To determine how changes in wing-vein arrangement affect elastic wing deformation during free flight, we compared elastic wing deformations between free-flying rose chafers (Protaetia cuprea) and dung beetles (Scarabaeus puncticollis), complementing the comparison with wing static bending measurements. The broader relevance of the results to scarab beetle divergence was examined in a geometric morphometric (GM) analysis of wing-vein arrangement in 20 species differing in phylogeny and ecology. Despite rose chafers and dung beetles demonstrating similar flapping kinematics and wing size, the rose chafer wings undergo greater elastic deformation during flapping. GM analyses corrected for phylogenetic relatedness revealed that the two beetles represent extremes in wing morphology among the scarab subfamilies. Most of the differences occur at the distal leading edge and the proximal trailing edge of the wing, diversifying the flexibility of these regions, thereby changing the pattern of elastic wing deformation during flapping. Changes to local wing compliance seem to be associated with the diversification of scarab beetles to different food sources, perhaps as an adaptation to meet the demands of diverse flight styles.

2.
J Evol Biol ; 26(6): 1281-93, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23458151

RESUMO

Exaggerated male ornaments are predicted to be costly to their bearers, but these negative effects may be offset by the correlated evolution of compensatory traits. However, when locomotor systems, such as wings in flying species, evolve to decrease such costs, it remains unclear whether functional changes across related species are achieved via the same morphological route or via alternate changes that have similar function. We conducted a comparative analysis of wing shape in relation to eye-stalk elongation across 24 species of stalk-eyed flies, using geometric morphometrics to determine how species with increased eye span, a sexually selected trait, have modified wing morphology as a compensatory mechanism. Using traditional and phylogenetically informed multivariate analyses of shape in combination with phenotypic trajectory analysis, we found a strong phylogenetic signal in wing shape. However, dimorphic species possessed shifted wing veins with the result of lengthening and narrowing wings compared to monomorphic species. Dimorphic species also had changes that seem unrelated to wing size, but instead may govern wing flexion. Nevertheless, the lack of a uniform, compensatory pattern suggests that stalk-eyed flies used alternative modifications in wing structure to increase wing area and aspect ratio, thus taking divergent morphological routes to compensate for exaggerated eye stalks.


Assuntos
Evolução Biológica , Dípteros/anatomia & histologia , Filogenia , Asas de Animais/anatomia & histologia , Animais , Dípteros/classificação , Masculino
3.
Regul Toxicol Pharmacol ; 52(1 Suppl): S82-90, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18022741

RESUMO

Grunerite asbestos (amosite) has been shown in epidemiological and experimental animal studies to cause lung cancer, mesothelioma and pulmonary fibrosis commonly referred to as asbestosis. An overview of the human and experimental animal studies describing the health hazards of grunerite asbestos (amosite) is presented. Of the many human studies describing the health hazards of asbestos, only three factories using mainly, if not exclusively, grunerite asbestos (amosite) have been studied. The first is a series of reports on a cohort of 820 workers from a plant located in Paterson, NJ. Among this cohort, 18.7% died of lung cancer and 17 mesotheliomas occurred. The Paterson factory closed in 1954 and moved to Tyler, Texas where it operated until 1972. Among the 1130 former workers in the Tyler plant 6 mesotheliomas were reported with 15.8% lung cancer mortality. The third grunerite asbestos (amosite) exposed cohort was an insulation board manufacturing facility in Uxbridge, United Kingdom. Here 17.1% of the workers died of lung cancer and 5 mesotheliomas occurred. The lung content from 48 Uxbridge workers was analyzed by analytical transmission electron microscopy for mineral fibers. The relationship between grunerite asbestos (amosite) concentrations in the lung correlated with grades of fibrosis and asbestos bodies and was lower than the concentration found in the cases with malignant tumors. The lung cancer cases contained more grunerite asbestos (amosite) than mesothelioma cases, and in the cases of non-malignant disease the concentrations were still lower. In both types of malignancies the concentration of grunerite asbestos (amosite) was very high-over a billion fibers per gram of dried lung tissue. Occupational exposure to airborne concentrations of between 14 and 100 fibers of grunerite asbestos (amosite) per milliliter after 20 year latency causes marked increases in lung cancer, mesothelioma and pulmonary fibrosis (asbestosis).


Assuntos
Poluentes Ocupacionais do Ar/efeitos adversos , Amianto Amosita/efeitos adversos , Asbestose/etiologia , Poluentes Ocupacionais do Ar/análise , Poluentes Ocupacionais do Ar/farmacocinética , Animais , Amianto Amosita/análise , Amianto Amosita/farmacocinética , Estudos de Coortes , Modelos Animais de Doenças , Humanos , Pulmão/química , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Mesotelioma/etiologia , Mesotelioma/metabolismo , Mesotelioma/mortalidade , New Jersey/epidemiologia , Texas/epidemiologia , Reino Unido/epidemiologia
4.
Clin Lab ; 53(9-12): 571-4, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18257463

RESUMO

The elderly have higher INR values, but this may be due to factors such as inter-current illnesses or drug changes. In the following case-controlled study we contacted 304 patients receiving warfarin treatment, one group with an INR of 5 or more, and three control groups (INR < 2, 2-3.9, 4-4.9). Variables that significantly predicted an INR of 5 or more in a logistic regression model included age, the use of antibiotics, stopping of a chronic drug, and the lack of knowledge of the target INR. After forcing in other variables associated with age (less valve disease, more use of multivitamins, and a lower dose of warfarin) the increased risk was 1.6 (1.12-2.28) per 10 years of age. We conclude that age is an independent risk factor for INR values of 5 or more.


Assuntos
Anticoagulantes/farmacologia , Hemostasia/efeitos dos fármacos , Coeficiente Internacional Normatizado , Varfarina/farmacologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Hemostasia/fisiologia , Humanos
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