Quality of life in children with unilateral hearing loss: a pilot study

The purpose of this investigation was to determine the impact of unilateral hearing loss on the quality of life of children. Focus group sessions were held for parents and children or adolescents with unilateral hearing loss to discuss their perceptions. Parents and children or adolescents completed the Pediatric Quality of Life Inventory. Findings were presented depicting which domains of quality of life are most affected.

Velocity discrimination of angular motion at different frequencies in individuals with normal vestibular function

The purpose of this study was to evaluate discrimination of angular velocity in individuals with normal vestibular function using a newly developed adaptive psychophysical measure. Vestibular psychophysical testing may complement existing clinical measures in diagnosing and treating patients with imbalance.

Temporal processing in listeners with unilateral hearing loss

Temporal processing is examined for sounds delivered to the intact ear of individuals with unilateral hearing, and delivered to one ear of individuals with normal, bilateral hearing. Two temporal processing skills are assessed: 1) the ability to detect sinusoidal amplitude modulation of a wide-band noise, for various modulation frequencies, and 2) the just-noticeable-difference for temporal complexity of random-spectrogram-sounds.

Effect of unilateral hearing loss on the speech-evoked auditory brainstem response in the presence of noise

Speech-evoked auditory brainstem responses (ABRs) were acquired in quiet and in the presence of noise at two study sessions to investigate 1) test-retest variability and 2) subcortical representation of speech stimuli. Participants were adults with normal hearing in both ears who listened monaurally and adults with unilateral deafness. Results indicate consistency in responses across sessions and several differences between hearing groups for magnitudes of discrete components.

Ocular vestibular evoked myogenic potentials (oVEMP) using air conducted sound: Effect of body position on threshold

The primary objective of this research study is to determine if various body positions for ocular vestibular evoked myogenic potential (oVEMP) testing demonstrate differentiation of the saccule and utricle through threshold responses.

Outcomes of conventional amplification for pediatric unilateral hearing loss

Although some children with unilateral hearing loss (UHL) are at-risk for educational difficulties and behavioral problems, research in treatment outcomes for pediatric UHL is limited. The objective of this study was to examine the benefits of a conventional hearing aid in children with mild to moderately severe UHL, using speech perception measures and subjective assessments from the child, parent, and teacher.

Inseguridad jurídica en la ejecución de la sanción administrativa en la terminación unilateral del contrato administrativo

La Ley de Contratación Pública y el Reglamento Sustitutivo para Registro de Contratistas Incumplidos y Adjudicatarios Fallidos, Registro de Contratos, Registro de Garantías de Contratos y Régimen de Excepción, establecen que la inhabilidad para contratar con el Estado de los contratistas incumplidos y también de los adjudicatarios fallidos, una vez resuelto por parte de la Administración Pública la terminación unilateral y anticipada de un contrato de obra, bien o servicio o la negativa del oferente a suscribir el contrato, será de cuatro y tres años respectivamente, contados a partir de la ejecución de la garantía de fiel cumplimiento del contrato. Sin embargo, en la práctica la sanción o inhabilidad del contratista o adjudicatario fallido sancionado, va más allá de lo que la Codificación de la Ley de Contratación Pública y el Reglamento Sustitutivo para el Registro de Contratistas Incumplidos y Adjudicatarios Fallidos, Registro de Contratos, Registro de Garantías de Contratos y Régimen de Excepción determinan. De hecho la sanción impuesta al contratista incumplido o al adjudicatario fallido, por parte de la administración pública, empezaba desde el momento mismo en que la Contraloría General del Estado tomaba conocimiento de la resolución de terminación unilateral y anticipada del contrato, mediante la cual resolvía, entre otras cosas el registro como contratista incumplido o adjudicatario fallido en la entidad de control, incumpliendo de esta manera lo que la Ley y el Reglamento prescribía respecto a que la sanción produciría efecto desde la fecha en que la entidad pública emisora de la sanción ejecutaba la garantía de fiel cumplimiento del contrato o de seriedad de la oferta, según el caso.

Modificación unilateral en los contratos públicos

Debido a la gran cantidad y diversidad de cuestiones que maneja el Estado por la vía de la función administrativa, la Administración Pública tiene la necesidad de realizar convenios y contratos que le permitan efectuar acciones tendientes a la consecución de sus fines, a través de relaciones con particulares. Considerando que las características diferenciadoras del derecho privado son el objeto y las prerrogativas especiales que posee la administración especialmente la modificación, esta investigación se desarrolla en tres capítulos: Capítulo I: Definición del contrato público y su modificación, los principios de inmutabilidad y mutabilidad y, la aplicación de los principios jurídicos que rigen el derecho administrativo desde el punto de vista de Cassagne. Capítulo II: La desigualdad jurídica que existe entre el Estado y el Particular, la modificación unilateral de los contratos de obra pública, prestación del servicio público y adquisición de bienes con sus consecuentes limitaciones y, la modificación unilateral de los contratos petroleros. Capítulo III: Formas de modificación de los contratos: órdenes de cambio, contratos complementarios, contratos adicionales, reajuste o revisión de precios, la renegociación y el otro sí. El estudio finiquita, con las conclusiones y recomendaciones derivadas de las legislaciones comparadas de Argentina, Colombia, Costa Rica, Ecuador y España.

Impulsiveness as a timing disturbance: neurocognitive abnormalities in attention-deficit hyperactivity disorder during temporal processes and normalization with methylphenidate.

We argue that impulsiveness is characterized by compromised timing functions such as premature motor timing, decreased tolerance to delays, poor temporal foresight and steeper temporal discounting. A model illustration for the association between impulsiveness and timing deficits is the impulsiveness disorder of attention-deficit hyperactivity disorder (ADHD). Children with ADHD have deficits in timing processes of several temporal domains and the neural substrates of these compromised timing functions are strikingly similar to the neuropathology of ADHD. We review our published and present novel functional magnetic resonance imaging data to demonstrate that ADHD children show dysfunctions in key timing regions of prefrontal, cingulate, striatal and cerebellar location during temporal processes of several time domains including time discrimination of milliseconds, motor timing to seconds and temporal discounting of longer time intervals. Given that impulsiveness, timing abnormalities and more specifically ADHD have been related to dopamine dysregulation, we tested for and demonstrated a normalization effect of all brain dysfunctions in ADHD children during time discrimination with the dopamine agonist and treatment of choice, methylphenidate. This review together with the new empirical findings demonstrates that neurocognitive dysfunctions in temporal processes are crucial to the impulsiveness disorder of ADHD and provides first evidence for normalization with a dopamine reuptake inhibitor.

Unilateral incompatibility in Capsicum (Solanaceae): Occurrence and taxonomic distribution

Background and aims Unilateral incompatibility (UI) occurs when pollinations between species are successful in one direction but not in the other. Self-incompatible (SI) species frequently show UI with genetically related, self-compatible (SC) species, as pollen of SI species is compatible on the SC pistil, but not vice versa. Many examples of unilateral incompatibility, and all those which have been studied most intensively, are found in the Solanaceae, particularly Lycopersicon, Solanum, Nicotiana and Petunia. The genus Capsicum is evolutionarily somewhat distant from Lycopersicon and Solanum and even further removed from Nicotiana and Petunia. Unilateral incompatibility has also been reported in Capsicum; however, this is the first comprehensive study of crosses between all readily available species in the genus. Methods All readily available (wild and domesticated) species in the genus are used as plant material, including the three genera from the Capsicum pubescens complex plus eight other species. Pollinations were made on pot-grown plants in a glasshouse. The number of pistils pollinated per cross varied (from five to 40 pistils per plant), depending on the numbers of flowers available. Pistils were collected 24 h after pollination and fixed for 3-24 h. After staining, pistils were mounted in a drop of stain, squashed gently under a cover slip and examined microscopically under ultra-violet light for pollen tube growth. Key results Unilateral incompatibility is confirmed in the C. pubescens complex. Its direction conforms to that predominant in the Solanaceae and other families, i.e. pistils of self-incompatible species, or self-compatible taxa closely related to self-incompatible species, inhibit pollen tubes of self-compatible species. Conclusions Unilateral incompatibility in Capsicum does not seem to have arisen to prevent introgression of self-compatibility into self-incompatible taxa, but as a by-product of divergence of the C. pubescens complex from the remainder of the genus. (C) 2004 Annals of Botany Company.

A functional proteomic method for the enrichment of peripheral membrane proteins reveals the collagen binding protein Hsp47 is exposed on the surface of activated human platelets

Platelets are small blood cells vital for hemostasis. Following vascular damage, platelets adhere to collagens and activate, forming a thrombus that plugs the wound and prevents blood loss. Stimulation of the platelet collagen receptor glycoprotein VI (GPVI) allows recruitment of proteins to receptor-proximal signaling complexes on the inner-leaflet of the plasma membrane. These proteins are often present at low concentrations; therefore, signaling-complex characterization using mass spectrometry is limited due to high sample complexity. We describe a method that facilitates detection of signaling proteins concentrated on membranes. Peripheral membrane proteins (reversibly associated with membranes) were eluted from human platelets with alkaline sodium carbonate. Liquid-phase isoelectric focusing and gel electrophoresis were used to identify proteins that changed in levels on membranes from GPVI-stimulated platelets. Immunoblot analysis verified protein recruitment to platelet membranes and subsequent protein phosphorylation was preserved. Hsp47, a collagen binding protein, was among the proteins identified and found to be exposed on the surface of GPVI-activated platelets. Inhibition of Hsp47 abolished platelet aggregation in response to collagen, while only partially reducing aggregation in response to other platelet agonists. We propose that Hsp47 may therefore play a role in hemostasis and thrombosis.

Peripheral tachykinins and the neurokinin receptor NK1 are required for platelet thrombus formation

Platelets play an important role in hemostasis, with inappropriate platelet activation being a major contributor to debilitating and often fatal thrombosis by causing myocardial infarction and stroke. Although current antithrombotic treatment is generally well tolerated and effective, many patients still experience cardiovascular problems, which may reflect the existence of alternative underlying regulatory mechanisms in platelets to those targeted by existing drugs. In this study, we define a role for peripherally distributed members of the tachykinin family of peptides, namely substance P and the newly discovered endokinins A and B that are present in platelets, in the activation of platelet function and thrombus formation. We have reported previously that the preferred pharmacologically characterized receptor for these peptides, the NK1 receptor, is present on platelets. Inhibition or deficiency of the NK1 receptor, or SP agonist activity, resulted in substantially reduced thrombus formation in vitro under arterial flow conditions, increased bleeding time in mice, and a decrease in experimentally induced thromboembolism. Inhibition of the NK1 receptor may therefore provide benefit in patients vulnerable to thrombosis and may offer an alternative therapeutic target.