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1.
Bioessays ; 36(2): 141-50, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24375688

RESUMO

Like biological species, languages change over time. As noted by Darwin, there are many parallels between language evolution and biological evolution. Insights into these parallels have also undergone change in the past 150 years. Just like genes, words change over time, and language evolution can be likened to genome evolution accordingly, but what kind of evolution? There are fundamental differences between eukaryotic and prokaryotic evolution. In the former, natural variation entails the gradual accumulation of minor mutations in alleles. In the latter, lateral gene transfer is an integral mechanism of natural variation. The study of language evolution using biological methods has attracted much interest of late, most approaches focusing on language tree construction. These approaches may underestimate the important role that borrowing plays in language evolution. Network approaches that were originally designed to study lateral gene transfer may provide more realistic insights into the complexities of language evolution.


Assuntos
Transferência Genética Horizontal/genética , Evolução Biológica , Células Procarióticas/metabolismo
2.
Proc Biol Sci ; 278(1713): 1794-803, 2011 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-21106583

RESUMO

Language evolution is traditionally described in terms of family trees with ancestral languages splitting into descendent languages. However, it has long been recognized that language evolution also entails horizontal components, most commonly through lexical borrowing. For example, the English language was heavily influenced by Old Norse and Old French; eight per cent of its basic vocabulary is borrowed. Borrowing is a distinctly non-tree-like process--akin to horizontal gene transfer in genome evolution--that cannot be recovered by phylogenetic trees. Here, we infer the frequency of hidden borrowing among 2346 cognates (etymologically related words) of basic vocabulary distributed across 84 Indo-European languages. The dataset includes 124 (5%) known borrowings. Applying the uniformitarian principle to inventory dynamics in past and present basic vocabularies, we find that 1373 (61%) of the cognates have been affected by borrowing during their history. Our approach correctly identified 117 (94%) known borrowings. Reconstructed phylogenetic networks that capture both vertical and horizontal components of evolutionary history reveal that, on average, eight per cent of the words of basic vocabulary in each Indo-European language were involved in borrowing during evolution. Basic vocabulary is often assumed to be relatively resistant to borrowing. Our results indicate that the impact of borrowing is far more widespread than previously thought.


Assuntos
Evolução Cultural , Idioma , Modelos Teóricos , Humanos , Linguística
3.
Am J Phys Anthropol ; 143(2): 235-49, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20853478

RESUMO

This study investigates patterns of mobility in Early Medieval Bavaria through a combined study of diet and associated burial practice. Carbon and nitrogen isotope ratios were analyzed in human bone samples from the Late Roman cemetery of Klettham and from the Early Medieval cemeteries of Altenerding and Straubing-Bajuwarenstrasse. For dietary comparison, samples of faunal bone from one Late Roman and three Early Medieval settlement sites were also analyzed. The results indicate that the average diet was in keeping with a landlocked environment and fairly limited availability of freshwater or marine resources. The diet appears not to have changed significantly from the Late Roman to the Early Medieval period. However, in the population of Altenerding, there were significant differences in the diet of men and women, supporting a hypothesis of greater mobility among women. Furthermore, the isotopic evidence from dietary outliers is supported by "foreign" grave goods and practices, such as artificial skull modification. These results reveal the potential of carbon and nitrogen isotope analysis for questions regarding migration and mobility.


Assuntos
Isótopos de Carbono/análise , Dieta , Emigração e Imigração , Isótopos de Nitrogênio/análise , Paleontologia , Adulto , Idoso , Animais , Sepultamento , Bovinos , Colágeno Tipo I/análise , Colágeno Tipo I/metabolismo , Feminino , Fósseis , Geografia , Alemanha , História Medieval , Humanos , Masculino , Pessoa de Meia-Idade , Panicum , Crânio , Estatísticas não Paramétricas , Suínos
4.
Basic Clin Pharmacol Toxicol ; 96(5): 366-74, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15853929

RESUMO

This paper investigates the possible antinociceptive effect of systemically administered ciprofloxacin and gentamicin and its influence on intrathecal morphine-induced antinociception. Using thermal nociceptive tests (hot-plate test and tail-flick test) and a motor function test (catalepsy test) in male Sprague-Dawley rats (n=5-9/dose), the following observations were made: ciprofloxacin administered intraperitoneally in the dose range 4-64 mg/kg demonstrated a modest antinociceptive effect in both nociceptive tests. Solvent of ciprofloxacin (intraperitoneally) and saline (intraperitoneally), given as a control, showed no effect. Gentamicin, administered at a dose of 0.1-4 mg/kg intraperitoneally, demonstrated a significant (P<0.05) antinociceptive effect in the tail-flick test but not in the hot-plate test. However, opioid antagonists caused no significant change in the antibiotics. Furthermore, ciprofloxacin intraperitoneally produced a significant left-shift in the hot-plate test (ED50 saline-morphine=2.86 [CI 95%: 2.2, 4.32]microg; ED50 ciprofloxacin-morphine=0.87 (CI 95% 0.68, 1.21) microg, P<0.05) and in the tail-flick test (ED50 saline-morphine=1.98 (CI 95%: 1.21, 2.84) microg; ED50 ciprofloxacin-morphine=0.37 (CI 95%: 0.23, 0.44) microg; P<0.05) for intrathecal morphine-induced antinociception. From a comparison of these data with the predicted ciprofloxacin-morphine value (hot-plate test: 1.61 (CI 95%: 1.18, 2.51]microg; tail-flick test: 0.82 (CI 95%: 0.52, 1.92) microg) we estimate that ciprofloxacin and morphine produce at least additive effects (P>0.05). This was reversed with intraperitoneal naloxone (P<0.05). Gentamicin intraperitoneally did not influence the antinociception achieved with intrathecal administration of morphine (hot-plate test: ED50 gentamicin-morphine=2.71 (CI 95%: 2.35; 3.2) microg; tail-flick test: ED50 gentamicin-morphine=2.43 (CI 95%: 1.58; 5.22]microg; P>0.05). These data show that intraperitoneal administration of ciprofloxacin and gentamicin produces a modest antinociceptive effect in the hot-plate test and tail-flick test. Ciprofloxacin, but not gentamicin, can interact at least additively to increased naloxone-reversible morphine intrathecal antinociception. Differences in the ability to penetrate the blood-brain barrier between the two antibiotics could explain the lack of effect from gentamicin in the hot plate and on morphine-induced antinociception.


Assuntos
Analgésicos/uso terapêutico , Comportamento Animal/efeitos dos fármacos , Ciprofloxacina/uso terapêutico , Gentamicinas/uso terapêutico , Morfina/uso terapêutico , Dor/tratamento farmacológico , Animais , Sinergismo Farmacológico , Feminino , Injeções Intraperitoneais , Injeções Espinhais , Atividade Motora/efeitos dos fármacos , Naloxona/farmacologia , Medição da Dor , Ratos , Ratos Sprague-Dawley
5.
Brain Lang ; 128(1): 41-52, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24412808

RESUMO

The current study investigated sensorimotor involvement in the processing of verbs describing actions performed with the hands, feet, or no body part. Actual movements were used to identify neuromagnetic sources for hand and foot actions. These sources constrained the analysis of verb processing. While hand and foot sources picked up activation in all three verb conditions, peak amplitudes showed an interaction of source and verb condition at 200 ms after word onset, thereby reflecting effector-specificity. Specifically, hand verbs elicited significantly higher peak amplitudes than foot verbs in hand sources. Our results are in line with theories of embodied cognition that assume an involvement of sensorimotor areas in early stages of lexico-semantic processing, even for single words without a semantic or motor task.


Assuntos
Encéfalo/fisiologia , Pé/fisiologia , Mãos/fisiologia , Movimento/fisiologia , Semântica , Percepção da Fala/fisiologia , Comportamento Verbal , Cognição/fisiologia , Potenciais Evocados , Feminino , Humanos , Magnetoencefalografia , Masculino , Lobo Parietal/fisiologia , Adulto Jovem
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