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1.
Epilepsy Res ; 200: 107287, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38237219

RESUMEN

PURPOSE: Validated measures capable of demonstrating meaningful interventional change in the CDKL5 deficiency disorder (CDD) are lacking. The study objective was to modify the Rett Syndrome Gross Motor Scale (RSGMS) and evaluate its psychometric properties for individuals with CDD. METHODS: Item and scoring categories of the RSGMS were modified. Caregivers registered with the International CDKL5 Clinical Research Network uploaded motor videos filmed at home to a protected server and completed a feedback questionnaire (n = 70). Rasch (n = 137), known groups (n = 109), and intra- and inter-rater reliability analyses (n = 50) were conducted. RESULTS: The age of individuals with CDD ranged from 1.5 to 34.1 years. The modified scale, Gross Motor-Complex Disability (GM-CD), comprised 17 items. There were no floor or ceiling effects and inter- and intra-rater reliability were good. Rasch analysis demonstrated that the items encompassed a large range of performance difficulty, although there was some item redundancy and some disordered categories. One item, Prone Head Position, was a poor fit. Caregiver-reported acceptability was positive. Scores differed by age and functional abilities. SUMMARY: GM-CD appears to be a suitable remotely administered measure and psychometrically sound for individuals with CDD. This study provides the foundation to propose the use of GM-CD in CDD clinical trials. Longitudinal evaluation is planned.


Asunto(s)
Síndromes Epilépticos , Síndrome de Rett , Espasmos Infantiles , Humanos , Lactante , Preescolar , Niño , Adolescente , Adulto Joven , Adulto , Psicometría , Destreza Motora , Reproducibilidad de los Resultados , Síndrome de Rett/diagnóstico , Síndrome de Rett/genética , Proteínas Serina-Treonina Quinasas/genética
2.
4.
BMC Public Health ; 21(1): 448, 2021 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-33673812

RESUMEN

BACKGROUND: COVID-19 continues to represent the single biggest challenge to contemporary community sport globally. Compliance with social distancing policies, strict return-to-play protocols, and COVID-19 specific training has, perhaps, forever changed the way that children and young people engage in organised sport. Within this context, and while many children and families seek to re-engage with community sport, we (researchers and sport practitioners) have an obligation to ask questions about how the pandemic has impacted youth sport, understand the short- and long-term consequences, and explore what (if any) opportunities can be seized to assist and improve future participation and retention. The aim of this paper was to present an in-depth exploration of the impact of COVID-19 on youth sport in South Australia. METHODS: Within an interpretive descriptive methodology, this qualitative investigation draws on rich, individual interview and focus group data with 39 youth (ages 15-18), parents, coaches, and sport administrators. A reflexive thematic analysis was undertaken, leading to the development of four substantive themes. RESULTS: We conceptualised the '4 Rs' to advance theoretical understandings about the pandemic's impact on youth sport, including the themes 'recognising struggle', 'reconnection', 're-engaging after restrictions, and 'reimagining sport'. The themes captured insights about a decline in mental wellbeing and physical activity, an increase in family connectedness, the challenge for sports to attract volunteers and participants back into sport, and the opportunities to reset values and philosophies underpinning the provision of youth sport. CONCLUSION: The findings provide valuable insight into the youth sport setting as a result of the global pandemic and suggest that families, sporting clubs and sporting organisations require additional resources and tools (for example, support for parents to facilitate their children's training at home during lockdown) to aid recovery efforts and to ensure the survival and prosperity of youth sport into the future.


Asunto(s)
COVID-19/epidemiología , COVID-19/psicología , Control de Enfermedades Transmisibles/estadística & datos numéricos , Cuarentena/psicología , Cuarentena/estadística & datos numéricos , Deportes Juveniles/psicología , Deportes Juveniles/estadística & datos numéricos , Adolescente , Australia , Niño , Femenino , Grupos Focales , Humanos , Masculino , Pandemias/estadística & datos numéricos , SARS-CoV-2 , Australia del Sur/epidemiología , Encuestas y Cuestionarios
5.
BMC Public Health ; 20(1): 332, 2020 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-32171278

RESUMEN

BACKGROUND: Alcohol-related hospital admissions have doubled in the last ten years to > 1.2 m per year in England. High-need, high-cost (HNHC) alcohol-related frequent attenders (ARFA) are a relatively small subgroup of patients, having multiple admissions or attendances from alcohol during a short time period. This trial aims to test the effectiveness of an assertive outreach treatment (AOT) approach in improving clinical outcomes for ARFA, and reducing resource use in the acute setting. METHODS: One hundred and sixty ARFA patients will be recruited and following baseline assessment, randomly assigned to AOT plus care as usual (CAU) or CAU alone in equal numbers. Baseline assessment includes alcohol consumption and related problems, physical and mental health comorbidity and health and social care service use in the previous 6 months using standard validated tools, plus a measure of resource use. Follow-up assessments at 6 and 12 months after randomization includes the same tools as baseline plus standard measure of patient satisfaction. Outcomes for CAU + AOT and CAU at 6 and 12 months will be compared, controlling for pre-specified baseline measures. Primary outcome will be percentage of days abstinent at 12 months. Secondary outcomes include emergency department (ED) attendance, number and length of hospital admissions, alcohol consumption, alcohol-related problems, other health service use, mental and physical comorbidity 6 and 12 months post intervention. Health economic analysis will estimate the economic impact of AOT from health, social care and societal perspectives and explore cost-effectiveness in terms of quality adjusted life years and alcohol consumption at 12-month follow-up. DISCUSSION: AOT models piloted with alcohol dependent patients have demonstrated significant reductions in alcohol consumption and use of unplanned National Health Service (NHS) care, with increased engagement with alcohol treatment services, compared with patients receiving CAU. While AOT interventions are costlier per case than current standard care in the UK, the rationale for targeting HNHC ARFAs is because of their disproportionate contribution to overall alcohol burden on the NHS. No previous studies have evaluated the clinical and cost-effectiveness of AOT for HNHC ARFAs: this randomized controlled trial (RCT) targeting ARFAs across five South London NHS Trusts is the first. TRIAL REGISTRATION: International standard randomized controlled trial number (ISRCTN) registry: ISRCTN67000214, retrospectively registered 26/11/2016.


Asunto(s)
Trastornos Relacionados con Alcohol/economía , Trastornos Relacionados con Alcohol/terapia , Utilización de Instalaciones y Servicios/economía , Utilización de Instalaciones y Servicios/estadística & datos numéricos , Adulto , Consumo de Bebidas Alcohólicas/epidemiología , Consumo de Bebidas Alcohólicas/prevención & control , Protocolos Clínicos , Análisis Costo-Beneficio , Servicio de Urgencia en Hospital/economía , Servicio de Urgencia en Hospital/estadística & datos numéricos , Femenino , Hospitalización/economía , Hospitalización/estadística & datos numéricos , Humanos , Londres/epidemiología , Masculino , Medicina Estatal/economía , Medicina Estatal/estadística & datos numéricos , Resultado del Tratamiento
6.
J Eval Clin Pract ; 24(2): 369-374, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29194899

RESUMEN

INTRODUCTION AND OBJECTIVE: The ODHIN trial found that training and support and financial reimbursement increased the proportion of patients that were screened and given advice for their heavy drinking in primary health care. However, the impact of these strategies on professional accuracy in delivering screening and brief advice is underresearched and is the focus of this paper. METHOD: From 120 primary health care units (24 in each jurisdiction: Catalonia, England, the Netherlands, Poland, and Sweden), 746 providers participated in the baseline and the 12-week implementation periods. Accuracy was measured in 2 ways: correctness in completing and scoring the screening instrument, AUDIT-C; the proportion of screen-negative patients given advice, and the proportion of screen-positive patients not given advice. Odds ratios of accuracy were calculated for type of profession and for intervention group: training and support, financial reimbursement, and internet-based counselling. RESULTS: Thirty-two of 36 711 questionnaires were incorrectly completed, and 65 of 29 641 screen-negative patients were falsely classified. At baseline, 27% of screen-negative patients were given advice, and 22.5% screen-positive patients were not given advice. These proportions halved during the 12-week implementation period, unaffected by training. Financial reimbursement reduced the proportion of screen-positive patients not given advice (OR = 0.56; 95% CI, 0.31-0.99; P < .05). CONCLUSION: Although the use of AUDIT-C as a screening tool was accurate, a considerable proportion of risky drinkers did not receive advice, which was reduced with financial incentives.


Asunto(s)
Alcoholismo/diagnóstico , Alcoholismo/terapia , Tamizaje Masivo/organización & administración , Atención Primaria de Salud/organización & administración , Errores Diagnósticos/estadística & datos numéricos , Femenino , Humanos , Masculino , Tamizaje Masivo/economía , Tamizaje Masivo/normas , Motivación , Atención Primaria de Salud/economía , Atención Primaria de Salud/normas
7.
Faraday Discuss ; 199: 335-347, 2017 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-28452382

RESUMEN

The anchoring of polymer chains at solid surfaces is an efficient way to modify interfacial properties like the stability and rheology of colloidal dispersions, lubrication and biocompatibility. Polyelectrolytes are good candidates for the building of smart materials, as the polyion chain conformation can often be tuned by manipulation of different physico-chemical variables. However, achieving efficient and reversible control of this process represents an important technological challenge. In this regard, the application of an external electrical stimulus on polyelectrolytes seems to be a convenient control strategy, for several reasons. First, it is relatively easy to apply an electric field to the material with adequate spatiotemporal control. In addition, in contrast to chemically induced changes, the molecular response to a changing electric field occurs relatively quickly. If the system is properly designed, this response can then be used to control the magnitude of surface properties. In this work we discuss the effect of an external electric field on the adhesion and lubrication properties of several polyelectrolyte-coated surfaces. The influence of the applied field is investigated at different pH and salt conditions, as the polyelectrolyte conformation is sensitive to these variables. We show that it is possible to fine tune friction and adhesion using relatively low applied fields.

8.
QJM ; 110(9): 559-564, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28379496

RESUMEN

BACKGROUND: Codeine misuse and dependence poses a clinical and public health challenge. However, little is known about dependence and treatment needs in the UK and Ireland. AIM: To characterize codeine use, dependence and help-seeking behaviour. DESIGN: An online cross-sectional survey advertised on Facebook, Twitter, health and drug websites and e-mail circulars. METHODS: The survey collected data on demographics and codeine use amongst adults from the UK and Ireland. The Severity of Dependence Scale measured the level of codeine dependence. RESULTS: The sample of 316 respondents had a mean age of 35.3 years (SD = 12.3) and 67% were women. Of the 316 respondents, 54 scored ≥5 on the Severity of Dependence Scale indicating codeine dependence (17.1%). Our study found that codeine dependence is a problem with both prescribed and 'over-the-counter' codeine. Codeine dependence was associated with daily use of codeine, faking or exaggerating symptoms to get a prescription for codeine and 'pharmacy shopping' ( P < 0.01). A higher number of respondents had sought advice on the Internet (12%) rather than from their general medical practitioner (GP) (5.4%). Less than 1% of respondents had sought advice from a pharmacist. CONCLUSIONS: Codeine dependent users were more likely to seek help on the Internet to control their use of codeine than from a GP, which may indicate a potential for greater specialized addiction treatment demand through increased identification and referrals in primary care.


Asunto(s)
Codeína , Abuso de Medicamentos , Conducta de Búsqueda de Ayuda , Trastornos Relacionados con Opioides , Adulto , Analgésicos Opioides/efectos adversos , Analgésicos Opioides/uso terapéutico , Codeína/efectos adversos , Codeína/uso terapéutico , Estudios Transversales , Abuso de Medicamentos/prevención & control , Abuso de Medicamentos/psicología , Abuso de Medicamentos/estadística & datos numéricos , Femenino , Medicina General/normas , Medicina General/estadística & datos numéricos , Humanos , Internet/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Evaluación de Necesidades , Medicamentos sin Prescripción/efectos adversos , Medicamentos sin Prescripción/uso terapéutico , Trastornos Relacionados con Opioides/diagnóstico , Trastornos Relacionados con Opioides/epidemiología , Trastornos Relacionados con Opioides/psicología , Medicamentos bajo Prescripción/efectos adversos , Medicamentos bajo Prescripción/uso terapéutico , Índice de Severidad de la Enfermedad , Reino Unido/epidemiología
9.
J Psychiatr Ment Health Nurs ; 24(6): 377-386, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28238207

RESUMEN

WHAT IS KNOWN ON THE SUBJECT?: A written plan is designed to improve communication and co-ordinate care between mental health inpatient wards and community settings. Reports of care plan quality issues and staff and service user dissatisfaction with healthcare bureaucracy have focused on working age mental health or general hospital settings. Little is known about mental health staff perspectives on the value of written care plans in supporting dementia care. WHAT THIS PAPER ADDS TO EXISTING KNOWLEDGE?: Competing demands on staff time and resources to meet administrative standards for care plans caused a tension with their own professional priorities for supporting care. Mental health staff face difficulties using electronic records alongside other systems of information sharing. Further exploration is needed of the gap between frontline staff values and those of the local organization and managers when supporting good dementia care. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: Frontline staff should be involved in designing new information systems including care plans. Care plan documentation needs to be refocused to ensure it is effective in enabling staff to communicate amongst themselves and with others to support people with dementia. Practice-based mentors could be deployed to strengthen good practice in effective information sharing. ABSTRACT: Background Reports of increased healthcare bureaucracy and concerns over care plan quality have emerged from research and surveys into staff and service user experiences. Little is known of mental health staff perspectives on the value of written care plans in supporting dementia care. Aim To investigate the experiences and views of staff in relation to care planning in dementia services in one National Health Service (NHS) provider Trust in England. Method Grounded Theory methodology was used. A purposive sample of 11 multidisciplinary staff were interviewed across three sites in one NHS Trust. Interviews were transcribed, coded and analysed using the constant comparative method. Findings Five themes were identified and are explored in detail below: (1) Repetition; (2) the impact of electronic records on practice; (3) ambivalence about the value of paperwork; (4) time conflicts; and (5) alternative sources of information to plan care. Discussion Participants perceived that written care plans did not help staff with good practice in planning care or to support dementia care generally. Staff were frustrated by repetitive documentation, inflexible electronic records and conflicting demands on their time. Implications for practice Frontline staff should be involved in designing new information systems including care plans.


Asunto(s)
Servicios Comunitarios de Salud Mental/normas , Demencia/enfermería , Personal de Salud/normas , Cuidados Paliativos/normas , Planificación de Atención al Paciente/normas , Servicio de Psiquiatría en Hospital/normas , Humanos
10.
Aust Dent J ; 58(3): 371-2, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23981221

RESUMEN

Perioral dermatitis is a papulopustular eruption, commonly related to the inappropriate application of topical corticosteroids with occasional reports of inhaled corticosteroids and decreased personal hygiene. We present a case of a 45-year-old female with a one-year history of perioral dermatitis related to the use of highly fluoridated toothpaste commenced to control dental caries.


Asunto(s)
Cariostáticos/efectos adversos , Dentífricos/efectos adversos , Dermatitis Perioral/inducido químicamente , Fluoruros/efectos adversos , Pastas de Dientes/efectos adversos , Caries Dental/prevención & control , Dentífricos/química , Dermatitis Perioral/tratamiento farmacológico , Femenino , Humanos , Persona de Mediana Edad , Pastas de Dientes/química
11.
Health Technol Assess ; 17(25): 1-158, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23796191

RESUMEN

BACKGROUND: There is clear evidence of the detrimental impact of hazardous alcohol consumption on the physical and mental health of the population. Estimates suggest that hazardous alcohol consumption annually accounts for 150,000 hospital admissions and between 15,000 and 22,000 deaths in the UK. In the older population, hazardous alcohol consumption is associated with a wide range of physical, psychological and social problems. There is evidence of an association between increased alcohol consumption and increased risk of coronary heart disease, hypertension and haemorrhagic and ischaemic stroke, increased rates of alcohol-related liver disease and increased risk of a range of cancers. Alcohol is identified as one of the three main risk factors for falls. Excessive alcohol consumption in older age can also contribute to the onset of dementia and other age-related cognitive deficits and is implicated in one-third of all suicides in the older population. OBJECTIVE: To compare the clinical effectiveness and cost-effectiveness of a stepped care intervention against a minimal intervention in the treatment of older hazardous alcohol users in primary care. DESIGN: A multicentre, pragmatic, two-armed randomised controlled trial with an economic evaluation. SETTING: General practices in primary care in England and Scotland between April 2008 and October 2010. PARTICIPANTS: Adults aged ≥ 55 years scoring ≥ 8 on the Alcohol Use Disorders Identification Test (10-item) (AUDIT) were eligible. In total, 529 patients were randomised in the study. INTERVENTIONS: The minimal intervention group received a 5-minute brief advice intervention with the practice or research nurse involving feedback of the screening results and discussion regarding the health consequences of continued hazardous alcohol consumption. Those in the stepped care arm initially received a 20-minute session of behavioural change counselling, with referral to step 2 (motivational enhancement therapy) and step 3 (local specialist alcohol services) if indicated. Sessions were recorded and rated to ensure treatment fidelity. MAIN OUTCOME MEASURES: The primary outcome was average drinks per day (ADD) derived from extended AUDIT--Consumption (3-item) (AUDIT-C) at 12 months. Secondary outcomes were AUDIT-C score at 6 and 12 months; alcohol-related problems assessed using the Drinking Problems Index (DPI) at 6 and 12 months; health-related quality of life assessed using the Short Form Questionnaire-12 items (SF-12) at 6 and 12 months; ADD at 6 months; quality-adjusted life-years (QALYs) (for cost-utility analysis derived from European Quality of Life-5 Dimensions); and health and social care resource use associated with the two groups. RESULTS: Both groups reduced alcohol consumption between baseline and 12 months. The difference between groups in log-transformed ADD at 12 months was very small, at 0.025 [95% confidence interval (CI)--0.060 to 0.119], and not statistically significant. At month 6 the stepped care group had a lower ADD, but again the difference was not statistically significant. At months 6 and 12, the stepped care group had a lower DPI score, but this difference was not statistically significant at the 5% level. The stepped care group had a lower SF-12 mental component score and lower physical component score at month 6 and month 12, but these differences were not statistically significant at the 5% level. The overall average cost per patient, taking into account health and social care resource use, was £488 [standard deviation (SD) £826] in the stepped care group and £482 (SD £826) in the minimal intervention group at month 6. The mean QALY gains were slightly greater in the stepped care group than in the minimal intervention group, with a mean difference of 0.0058 (95% CI -0.0018 to 0.0133), generating an incremental cost-effectiveness ratio (ICER) of £1100 per QALY gained. At month 12, participants in the stepped care group incurred fewer costs, with a mean difference of -£194 (95% CI -£585 to £198), and had gained 0.0117 more QALYs (95% CI -0.0084 to 0.0318) than the control group. Therefore, from an economic perspective the minimal intervention was dominated by stepped care but, as would be expected given the effectiveness results, the difference was small and not statistically significant. CONCLUSIONS: Stepped care does not confer an advantage over minimal intervention in terms of reduction in alcohol consumption at 12 months post intervention when compared with a 5-minute brief (minimal) intervention. TRIAL REGISTRATION: This trial is registered as ISRCTN52557360. FUNDING: This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 17, No. 25. See the HTA programme website for further project information.


Asunto(s)
Alcoholismo/diagnóstico , Anciano , Anciano de 80 o más Años , Alcoholismo/economía , Alcoholismo/terapia , Análisis Costo-Beneficio , Femenino , Costos de la Atención en Salud/estadística & datos numéricos , Humanos , Masculino , Tamizaje Masivo/métodos , Persona de Mediana Edad , Atención Primaria de Salud/economía , Atención Primaria de Salud/métodos , Factores de Riesgo , Resultado del Tratamiento , Reino Unido
12.
J Evol Biol ; 26(6): 1220-33, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23516990

RESUMEN

In animal-pollinated plants, local adaptation to pollinator behaviour or morphology can restrict gene flow among plant populations; but gene flow may also prevent divergent adaptation. Here, we examine possible effects of gene flow on plant-pollinator trait matching in two varieties of Joshua tree (Agavaceae: Yucca brevifolia). The two varieties differ in strikingly in floral morphology, which matches differences in the morphology of their pollinators. However, this codivergence is not present at a smaller scale: within the two varieties of Joshua tree, variation in floral morphology between demes is not correlated with differences in moth morphology. We use population genetic data for Joshua tree and its pollinators to test the hypotheses that gene flow between Joshua tree populations is structured by pollinator specificity, and that gene flow within the divergent plant-pollinator associations 'swamps' fine-scale coadaptation. Our data show that Joshua tree populations are structured by pollinator association, but the two tree varieties are only weakly isolated - meaning that their phenotypic differences are maintained in the face of significant gene flow. Coalescent analysis of gene flow between the two Joshua tree types suggests that it may be shaped by asymmetric pollinator specificity, which has been observed in a narrow zone of sympatry. Finally, we find evidence suggesting that gene flow among Joshua tree sites may shape floral morphology within one plant-pollinator association, but not the other.


Asunto(s)
Flujo Génico , Polen , Yucca/genética , Genes de Plantas , Fenotipo
13.
Cell Death Dis ; 4: e533, 2013 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-23470540

RESUMEN

Nutlin-3 selectively activates p53 by inhibiting the interaction of this tumor suppressor with its negative regulator murine double minute 2 (mdm2), while trichostatin A (TSA) is one of the most potent histone deacetylase (HDAC) inhibitors currently available. As both Nutlin-3 and TSA increase the levels of the cell cycle inhibitor p21(cip1/waf1) in cells, we investigated whether a combination of these compounds would further augment p21 levels. Contrary to expectations, we found that short-term exposure to Nutlin-3 and TSA in combination did not have an additive effect on p21 expression. Instead, we observed that activation of p53 prevented the ability of TSA to increase p21 levels. Furthermore, TSA inhibited Nutlin-3-induced expression of p53-dependent mRNAs including P21. This negative effect of TSA on Nutlin-3 was significantly less pronounced in the case of hdm2, another p53 downstream target. Aside from suggesting a model to explain these incompatible effects of Nutlin-3 and TSA, we discuss the implications of our findings in cancer therapy and cell reprogramming.


Asunto(s)
Puntos de Control del Ciclo Celular/efectos de los fármacos , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Inhibidores de Histona Desacetilasas/farmacología , Histona Desacetilasas/química , Proteína p53 Supresora de Tumor/antagonistas & inhibidores , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Células HCT116 , Histona Desacetilasas/metabolismo , Humanos , Ácidos Hidroxámicos/farmacología , Imidazoles/farmacología , Células MCF-7 , Piperazinas/farmacología , Proteínas Proto-Oncogénicas c-mdm2/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , ARN Mensajero/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo
15.
J Evol Biol ; 23(12): 2739-46, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21121087

RESUMEN

Coevolution is thought to promote evolutionary change between demes that ultimately results in speciation. If this is the case, then we should expect to see similar patterns of trait matching and phenotypic divergence between populations and between species in model systems for coevolution. As measures of divergence are frequently only available at one scale (population level or taxon level), this contention is rarely tested directly. Here, we use the case of co-divergence between different varieties of Joshua tree Yucca brevifolia (Agavaceae) and their obligate pollinators, two yucca moths (Tegeticula spp. Prodoxidae), to test for trait matching between taxa and among populations. Using model selection, we show that there is trait matching between mutualists at the taxon level, but once we account for differences between taxa, there is no indication of trait matching in local populations. This result differs from similar studies in other coevolving systems. We hypothesize that this discrepancy arises because coevolution in obligate mutualisms favours divergence less strongly than coevolution in other systems, such as host­parasite interactions.


Asunto(s)
Mariposas Nocturnas/anatomía & histología , Oviposición , Fenotipo , Polinización , Yucca/anatomía & histología , Animales , Evolución Biológica , Flores/anatomía & histología , Mariposas Nocturnas/fisiología , Dinámica Poblacional , Yucca/fisiología
16.
J Intellect Disabil Res ; 54(6): 573-7, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20576065

RESUMEN

BACKGROUND: Video conferencing (VC) technology has great potential to increase accessibility to healthcare services for those living in rural or underserved communities. Previous studies have had some success in validating a small number of psychological tests for VC administration; however, VC has not been investigated for use with persons with intellectual disabilities (ID). A comparison of test results for two well known and widely used assessment instruments was undertaken to establish if scores for VC administration would differ significantly from in-person assessments. METHOD: Nineteen individuals with ID aged 23-63 were assessed once in-person and once over VC using the Wechsler Abbreviated Scale of Intelligence (WASI) and the Beery-Buktenica Test of Visual-Motor Integration (VMI). RESULTS: Highly similar results were found for test scores. Full-scale IQ on the WASI and standard scores for the VMI were found to be very stable across the two administration conditions, with a mean difference of less than one IQ point/standard score. CONCLUSION: Video conferencing administration does not appear to alter test results significantly for overall score on a brief intelligence test or a test of visual-motor integration.


Asunto(s)
Discapacidad Intelectual/diagnóstico , Pruebas de Inteligencia/estadística & datos numéricos , Consulta Remota , Comunicación por Videoconferencia , Escalas de Wechsler/estadística & datos numéricos , Adulto , Femenino , Humanos , Masculino , Ontario , Psicometría/estadística & datos numéricos , Trastornos Psicomotores/diagnóstico , Reproducibilidad de los Resultados , Adulto Joven
17.
Heredity (Edinb) ; 105(2): 183-96, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20010961

RESUMEN

A wide range of evolutionary processes have been implicated in the diversification of yuccas and yucca moths, which exhibit ecological relationships that extend from obligate plant-pollinator mutualisms to commensalist herbivory. Prodoxus coloradensis (Lepidoptera: Prodoxidae) is a yucca moth, which feeds on the flowering stalks of three Yucca species as larvae, but does not provide pollination service. To test for evidence of host-associated speciation, we examined the genetic structure of P. coloradensis using mitochondrial (cytochrome oxidase I) and nuclear (elongation factor 1 alpha) DNA sequence data. Multilocus coalescent simulations indicate that moths on different host plant species are characterized by recent divergence and low levels of effective migration, with large effective population sizes and considerable retention of shared ancestral polymorphism. Although geographical distance explains a proportion of the mitochondrial and nuclear DNA variation among moths on different species of Yucca, the effect of host specificity on genetic distance remains significant after accounting for spatial isolation. The results of this study indicate that differentiation within P. coloradensis is consistent with the evolution of incipient species affiliated with different host plants, potentially influenced by sex-biased dispersal and female philopatry.


Asunto(s)
Evolución Molecular , Especiación Genética , Interacciones Huésped-Parásitos , Mariposas Nocturnas/genética , Yucca/parasitología , Animales , Complejo IV de Transporte de Electrones/genética , Femenino , Proteínas de Insectos/genética , Masculino , Mariposas Nocturnas/clasificación , Mariposas Nocturnas/fisiología , Factor 1 de Elongación Peptídica/genética , Filogenia , Polinización , Especificidad de la Especie
18.
Langmuir ; 25(19): 11472-9, 2009 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-19722607

RESUMEN

We have studied the behavior under compression and shear of two molecularly smooth mica surfaces immersed in aqueous solutions of a dimeric cationic surfactant and an oppositely charged polyelectrolyte-neutral diblock copolymer by using a surface force apparatus-nanotribometer, SFA-N. The surfactant and copolymer coadsorb as a mix molecular boundary lubricant film on the negatively charged mica surfaces leading to low friction in a sliding mechanical contact. However, under fritting conditions, shearing can induce different dynamic transitions of the confined films. Transitions from the initial low friction steady state to new steady states of low or high friction can be induced when the sliding velocity is increased above certain values. These dynamical transitions occur together with thickness reduction of the confined film. A reverse transition to the low friction steady state accompanied by the renovation of the film can be triggered by reintroducing some matter in the contact, via increasing the amplitude of the fritting cycles.


Asunto(s)
Lubricantes/química , Polímeros/química , Tensoactivos/química , Adsorción , Microscopía de Fuerza Atómica , Nanotecnología , Resistencia al Corte , Soluciones
19.
Langmuir ; 24(4): 1560-5, 2008 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-18179264

RESUMEN

The coadsorption from aqueous solutions of an anionic-neutral hydrophilic-hydrophilic diblock copolymer onto a mica-suported surfactant bilayer of a cationic oligomeric surfactant has been investigated. By using an atomic force microscope and a surface forces apparatus nanotribometer, we studied the resulting film morphology, the interactions between two coated surfaces, and the frictional properties of the boundary film. When the coated surfaces were compressed while being fully immersed in an aqueous surfactant solution, the hemifusion of the adsorbed surfactant bilayers could be easily induced. Noticeable friction forces could then be measured between the monolayer-coated surfaces. Coadsorbing poly(acrylic acid)-poly(acrylamide) diblock copolymer with the cationic surfactant changes the cohesion of the adsorbed layers. When the copolymer concentration is sufficiently high, the hemifusion instability of the adsorbed layers can be inhibited, considerably improving its lubricant properties.

20.
J Chem Phys ; 126(18): 184906, 2007 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-17508831

RESUMEN

The normal interaction and the behavior under shear of mica surfaces covered by two different triblock copolymers of polylysine-polydimethysiloxane-polylysine were studied by combining the capabilities of the surface forces apparatus and the atomic force microscopy. At low pH values these copolymers spontaneously adsorb on the negatively charged mica surfaces from aqueous solutions as a consequence of the positive charge of the polylysine moieties. The morphology of the adsorbed layer is determined by the molecular structure of the particular copolymer investigated. This morphology plays a fundamental role on the behavior of the adsorbed layers under shear and compression. While nonadhesive smooth layers oppose an extremely small resistance to sliding, the presence of asperities even at the nanometric scale originates a frictional resistance to the motion. The behavior of uniform nonadhesive nanorough surfaces under shear can be quantitatively understood in terms of a simple multistable thermally activated junction model. The electric charge of the adsorbed copolymer molecules and hence the adhesion energy between the coated surfaces can be modified by varying the pH of the surrounding media. In the presence of an adhesive interaction between the surfaces the behavior under shear is strongly modified. Time-dependent mechanisms of energy dissipation have to be evoked in order to explain the changes observed.

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