RESUMEN
The domestic goat is one of the most important livestock species, but its origins and genetic diversity still remain uncertain. Multiple highly divergent maternal lineages of goat have been reported in previous studies. Although one of the mitochondrial DNA lineages, lineage B, was detected only in eastern and southern Asia, the geographic distribution of these lineages was previously unclear. Here, we examine the genetic diversity and phylogeographic structure of Asian goats by mitochondrial DNA sequences and morphological characteristics. The analyses of a total of 1661 Asian goats from 12 countries revealed a high frequency of lineage B in Southeast Asia. The frequency of this lineage tended to be higher in mountain areas than in plain areas in Southeast Asian countries, and there was a significant correlation between its frequency and morphological traits. The results suggest an original predominance of lineage B in Southeast Asia and the recent infiltration of lineage A into Southeast Asian goats.
Asunto(s)
ADN Mitocondrial/genética , Variación Genética , Cabras/genética , Filogeografía , Animales , Asia Sudoriental , ADN Mitocondrial/sangre , Asia Oriental , Cabras/anatomía & histología , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Homología de SecuenciaRESUMEN
The technique used to align liquid crystals-rubbing the surface of a substrate on which a liquid crystal is subsequently deposited-has been perfected by the multibillion-dollar liquid-crystal display industry. However, it is widely recognized that a non-contact alignment technique would be highly desirable for future generations of large, high-resolution liquid-crystal displays. A number of alternative alignment techniques have been reported, but none of these have so far been implemented in large-scale manufacturing. Here, we report a non-contact alignment process, which uses low-energy ion beams impinging at a glancing angle on amorphous inorganic films, such as diamond-like carbon. Using this approach, we have produced both laptop and desktop displays in pilot-line manufacturing, and found that displays of higher quality and reliability could be made at a lower cost than the rubbing technique. The mechanism of alignment is explained by adopting a random network model of atomic arrangement in the inorganic films. Order is induced by exposure to an ion beam because unfavourably oriented rings of atoms are selectively destroyed. The planes of the remaining rings are predominantly parallel to the direction of the ion beam.
RESUMEN
A sensitive method of demonstrating latent imbalance of labyrinthine function was devised. The subject was asked to walk at his or her usual speed with eyes closed in a circle 2 m in diameter. This test was done by 22 patients whose vestibular function as tested by the Romberg, Mann, Fukuda and Babinski-Weil's methods had become normal after an attack of vertigo due to unilateral vestibular disorder. Eighteen patients complained of difficulty in walking while turning toward the affected side, and 11 tended to fall to the inside of the circle. Turning in the opposite direction, however, was performed without any difficulty. It was thought that disorders of the cristospinal reflex became manifest during circular walking toward the affected side. The body is inclined to the inner side of circular walking. Endolymph flows toward the ampulla of the lateral semicircular canal on the same side as turning. This would exert a facilitatory action on extensor neurons and give the ipsilateral leg assistance for supporting the body's weight which shifts to the centre of the circle. Disorders of the cristospinal reflex would cause difficulty in circular walking toward the affected side.
Asunto(s)
Enfermedades del Laberinto/diagnóstico , Reflejo/fisiología , Médula Espinal/fisiopatología , Pruebas de Función Vestibular , Vestíbulo del Laberinto/fisiopatología , Caminata , Humanos , Enfermedades del Laberinto/fisiopatologíaRESUMEN
This study comprised 22 normal adults, 12 males and 10 females. Electromyograms of the bilateral gastrocnemius muscle were recorded during circular walking under two conditions: no caloric stimulation and immediately after irrigating the right auditory canal with 20 degrees C water for 20 s with the horizontal semicircular canal maintained in vertical position. With no caloric stimulation, gastrocnemius muscle activity on the right side exceeded that on the left during dextrorotation and vice versa during sinistrorotation. Following irrigation of the right auditory canal, the activity was greater on the left side than on the right during sinistrorotation, but no consistent differences in muscle activity were observed during dextrorotation. Dextrorotation was associated with ataxic gait in all cases. Thus ampullopetal lymphatic flow in the semicircular canal due to circular walking causes increased antigravity muscle tonus of the ipsilateral leg. This gives the ipsilateral leg assistance for supporting body weight which shifts to the inner side of circular walking.