939 resultados para Library Web sites
Resumo:
Annual-layer thickness data, spanning AD 1534-2001, from an ice core from East Rongbuk Coll on Qomolangma (Mount Everest, Himalaya) yield an age-depth profile that deviates systematically from a constant accumulation-rate analytical model. The profile clearly shows that the mean accumulation rate has changed every 50-100 years. A numerical model was developed to determine the magnitude of these multi-decadal-scale rates. The model was used to obtain a time series of annual accumulation. The mean annual accumulation rate decreased from similar to 0.8 m ice equivalent in the 1500s to similar to 0.3 m in the mid-1800s. From similar to 1880 to similar to 1970 the rate increased. However, it has decreased since similar to 1970. Comparison with six other records from the Himalaya and the Tibetan Plateau shows that the changes in accumulation in East Rongbuk Col are broadly consistent with a regional pattern over much of the Plateau. This suggests that there may be an overarching mechanism controlling precipitation and mass balance over this area. However, a record from Dasuopu, only 125 km northwest of Qomolangma and 700 m higher than East Rongbuk Col, shows a maximum in accumulation during the 1800s, a time during which the East Rongbuk Col and Tibetan Plateau ice-core and tree-ring records show a minimum. This asynchroneity may be due to altitudinal or seasonal differences in monsoon versus westerly moisture sources or complex mountain meteorology.
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Retroviruses are RNA viruses that replicate through a double-stranded DNA intermediate. The viral enzyme reverse transcriptase copies the retroviral genomic RNA into this DNA intermediate through the process of reverse transcription. Many variables can affect the fidelity of reverse transcriptase during reverse transcription, including specific sequences within the retroviral genome. ^ Previous studies have observed that multiple cloning sites (MCS) and sequences predicted to form stable hairpin structures are hotspots for deletion during retroviral replication. The studies described in this dissertation were performed to elucidate the variables that affect the stability of MCS and hairpin structures in retroviral vectors. Two series of retroviral vectors were constructed and characterized in these studies. ^ Spleen necrosis virus-based vectors were constructed containing separate MCS insertions of varying length, orientation, and symmetry. The only MCS that was a hotspot for deletion formed a stable hairpin structure. Upon more detailed study, the MCS previously reported as a hotspot for deletion was found to contain a tandem linker insertion that formed a hairpin structure. Murine leukemia virus-based vectors were constructed containing separate sequence insertions of either inverted repeat symmetry (122IR) that could form a hairpin structure, or little symmetry (122c) that would form a less stable structure. These insertions were made into either the neomycin resistance marker ( neo) or the hygromycin resistance marker (hyg) of the vector. 122c was stable in both neo and hyg, while 122IR was preferentially deleted in neo and was remarkably unstable in hyg. ^ These results suggest that MCS are hotspots for deletion in retroviral vectors if they can form hairpin structures, and that hairpin structures can be highly unstable at certain locations in retroviral vectors. This information may contribute to improved design of retroviral vectors for such uses as human gene therapy, and will contribute to a greater understanding of the basic science of retroviral reverse transcription. ^
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In the United States, approximately 4,000 pregnancies each year are affected by the two most common birth defects, spina bifida and anencephaly. Studies have shown that exposure to environmental chemicals before and after conception may adversely affect reproduction by inducing cell death or dysfunction, which leads to infertility, fetal loss, lowered weight at birth, or birth anomalies in the offspring. The objective of the study was to evaluate the relationship between Neural Tube Defect births and residence at conception in proximity to hazardous waste sites in the Texas-Mexico border region between 1993 and 2000. ^ The study design was a nested matched case-control and utilized secondary data from a project, “The role of chemical and biological factors in the etiology of neural tube birth defects births along the Texas-Mexico Border” (Irina Cech, Principal Investigator). Geographic Information Systems (GIS) database methods were used to compare Neural Tube Defects cases to controls on status of conception residence occurring within a one-mile radius from hazardous waste sites, as compared to conception residence further away. Information on the exposures was obtained from the OnTarget Database and Environment Protection Agency website. Conditional logistic regression was used for the matched case-control study to investigate the relationship between an outcome of being a case or a control and proximity to hazardous waste sites. ^ The result of the study showed a 36 percent non-significant increased risk of having an NTD birth associated with maternal proximity to abandoned hazardous waste sites (95% CI = 0.62–3.02). In addition, there was a 24% non-significant elevated risk of having an NTD birth when living in proximity to air pollutant sites than when living further away (95% CI = 0.67–2.32). Although this study did not find statistically significant associations, it will expand on the existing knowledge of the relationship between NTD and proximity to hazardous waste sites. ^
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Current teen pregnancy and repeat pregnancy rates reveal that there is a pressing need for comprehensive care for pregnant and parenting teens to address their unique needs. The Internet has become a source of various types of information and as a result, several efforts have begun to assess the quality of health information provided on websites. The objective of this study was to assess the functionality and quality of websites containing health information and resources for pregnant and parenting teens. The three most widely used search engines currently: Google, MSN, and Yahoo were searched using three general search terms “teen pregnancy”, “pregnant teen”, and “teen parent”. The first 5 pages of each search were reviewed and categorized to yield 12 websites which met inclusion criteria for content evaluation. The 12 websites were rated using a pre-existing instrument encompassing two domains: functionality and content analysis. Within the functionality domain, this sample highlighted the need to improve accessibility and credibility for the target population. The content analysis revealed that among the topics which are recommended for pregnant and parenting teens, the topics most commonly covered were mental health and primary and preventive health care. The majority of websites neglected sexual health topics including STI’s and family planning. This study provides the first glimpse into health information and resources for pregnant and parenting teens on the Internet. Researchers, health care providers, social workers, health educators, and website sponsors can use these results to maintain and recommend websites which offer easily accessible, accurate, and practical information for pregnant and parenting teens.^
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Alcohol consumption has a long-standing tradition in the United States Air Force (USAF). From squadron bars to officers and enlisted clubs, alcohol has been used in social settings to increase morale and also as a way to help decrease the stress of military operations. Surveys have demonstrated that the USAF has more than double the percentage of heavy drinkers than the US population. More than one-third of the Air Force reports binge drinking in the last month while only six percent of the nation reports the same consumption pattern.^ However, alcohol has a significant harmful health effect if consumed in excess. As part of an overall prevention and treatment program aimed at curbing the harmful effects of alcohol consumption, the USAF uses the Alcohol Use Disorder Identification Test (AUDIT) to screen for high-risk alcohol consumption patterns before alcohol disorder and disability occur. All Air Force active-duty members are required to complete a yearly Preventive Health Assessment questionnaire. Various health topics are included in this questionnaire including nutrition, exercise, tobacco use, family history, mental health and alcohol use. While this questionnaire has been available in a web-based format for several years, mandatory use was not implemented until 2009.^ Although the AUDIT was selected due to its effectiveness in assessing high-risk alcohol consumption in other populations, its effectiveness in the Air Force population had not been studied previously. In order to assess the sensitivity, specificity, and positive predictive value of this screening tool, the Air Force Web-based Preventive Health Assessment alcohol screening results were compared to whether any alcohol-related diagnosis was made from January 1, 2009 to March 31, 2010.^ While the AUDIT has previously been shown to have a high sensitivity and specificity, the Air Force screening values were 27.9% and 93.0% respectively. Positive predictive value was only 4.9%. With the screening statistics found, less than one-third of those having an alcohol disorder will be found with this screening tool and only 1 out of 20 Airmen who require further evaluation actually have an alcohol-related diagnosis.^
Resumo:
The U.S. Air Force assesses Active Duty Air Force (ADAF) health annually using the Air Force Web-based Preventative Health Assessment (AF WebPHA). The assessment is based on a self-administered survey used to determine the overall Air Force health and readiness, as well as, the individual health of each airman. Individual survey responses as well as groups of responses generate further computer generated assessment and result in a classification of 'Critical', 'Priority', or 'Routine', depending on the need and urgency for further evaluation by a health care provider. The importance of the 'Priority' and 'Critical' classifications is to provide timely intervention to prevent or limit unfavorable outcomes that may threaten an airman. Though the USAF has been transitioning from a paper form to the online WebPHA survey for the last three years it was not made mandatory for all airmen until 2009. The survey covers many health aspects including family history, tobacco use, exercise, alcohol use, and mental health. ^ Military stressors such as deployment, change of station, and the trauma of war can aggravate and intensify the common baseline worries experienced by the general population and place airmen at additional risks for mental health concerns and illness. This study assesses the effectiveness of the AF WebPHA mental health screening questions in predicting a mental health disorder diagnosis according to International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) codes generated by physicians or their surrogates. In order to assess the sensitivity, specificity, and positive predictive value of the AF WebPHA as a screening tool for mental health, survey results were compared to ascertain if they generated any mental health disorder related diagnosis for the period from January 1, 2009 to March 31, 2010. ^ Statistical analysis of the AF WebPHA mental health responses when compared with matching ICD-9-CM codes found that the sensitivity for 'Critical' or 'Priority' responses was only 3.4% and that it would correctly predict those who had the selected mental health diagnosis 9% of the time.^
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The Internet, and specifically web 2.0 social media applications, offers an innovative method for communicating child health information to low-income parents. The main objective of this study was to use qualitative data to determine the value of using social media to reach low-income parents with child health information. A qualitative formative evaluation employing focus groups was used to determine the value of using social media for dissemination of child health information. Inclusion criteria included: (1) a parent with a child that attends a school in a designated Central Texas school district; and (2) English-speaking. The students who attend these schools are generally economically disadvantaged and are predominately Hispanic. The classic analysis strategy was used for data analysis. Focus group participants (n=19) were female (95%); White (53%), Hispanic (42%) or African American (5%); and received government assistance (63%). Most had access to the Internet (74%) and were likely to have low health literacy (53%). The most preferred source of child health information was the family pediatrician or general practitioner. Many participants were familiar with social media applications and had profiles on popular social networking sites, but used them infrequently. Objections to social media sites as sources of child health information included lack of credibility and parent time. Social media has excellent potential for reaching low-income parents when used as part of a multi-channel communication campaign. Further research should focus on the most effective type and format of messages that can promote behavior change in this population, such as story-telling. ^
Resumo:
Medical errors and close calls are pervasive in health care. It is hypothesized that the causes of close calls are the same as for medical errors; therefore learning about close calls can help prevent errors and increase patient safety. Yet despite efforts to encourage close call reporting, close calls as well as medical errors are under-reported in health care. The purpose of this dissertation was to implement and evaluate a web-based anonymous close call reporting system in three units at an urban hospital. ^ The study participants were physicians, nurses and medical technicians (N = 187) who care for patients in the Medical Intermediate Care Unit, the Surgical Intermediate Care Unit, and the Coronary Catheterization Laboratory in the hospital. We provided educational information to the participants on how to use the system and e-mailed and delivered paper reminders to report to the participants throughout the 19-month project. We surveyed the participants at the beginning and at the end of the study to assess their attitudes and beliefs regarding incident reporting. We found that the majority of the health care providers in our study are supportive of incident reporting in general but in practice very few had actually reported an error or a close call, semi-structured interview 20 weeks after we made the close call reporting system available. The purpose of the interviews was to further assess the participants' attitudes regarding incident reporting and the reporting system. Our findings suggest that the health care providers are supportive of medical error reporting in general, but are not convinced of the benefit of reporting close calls. Barriers to close call reporting cited include lack of time, heavy workloads, preferring to take care of close calls "on the spot", and not seeing the benefits of close call reporting. Consequently only two = close calls were reported via the system by two separate caregivers during the project. ^ The findings suggest that future efforts to increase close call reporting must address barriers to reporting, especially the belief among care givers that it is not worth taking time from their already busy schedules to report close calls. ^
Resumo:
Tradicionalmente las bibliotecas universitarias vienen recopilando datos estadísticos sobre las colecciones, actividades y servicios acotados al trabajo in situ. Sin embargo, en la actualidad también se requiere contar con información sobre el uso de los recursos y servicios electrónicos disponibles a través de la web. En este sentido han surgido varios proyectos e iniciativas de desarrollo de indicadores específicamente orientados a su medición, que reciben la denominación genérica de e-metrics. No existe aún consenso sobre una herramienta operativa específica para el cálculo de estos indicadores. No obstante, hay una variedad de herramientas gratuitas de aplicación general para estadísticas de sitios Web, que pueden ser de utilidad para la evaluación del uso de los recursos y servicios web de las bibliotecas. Este trabajo se propone comparar diferentes herramientas estadísticas disponibles y analizar la utilidad potencial para el ámbito de las bibliotecas.
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Se aborda el estudio de la evaluación de los repositorios institucionales desde una perspectiva cibermétrica. En primer lugar se presenta la sede online universitaria como un sistema complejo y rico documentalmente, analizable desde un punto de vista tanto sistémico como cuantitativo. Tras ello, se sitúa el repositorio institucional como una sede independiente alojada dentro de la sede académica, con unos objetivos y características propios, y que pueden ser igualmente analizados desde un punto de vista cibermétrico. A continuación se exponen los indicadores cibermétricos más importantes utilizados en el análisis de repositorios institucionales (aplicando su uso a SeDICI, repositorio institucional de la Universidad Nacional de la Plata). Se finaliza con la presentación del Ranking Web de Repositorios del Mundo, en el que se aplican diversos indicadores cibermétricos, analizando la presencia de los repositorios institucionales argentinos en el mismo.
Resumo:
Se presenta el proyecto de investigación aprobado y subsidiado en el marco de la Programación Científica UBACYT 2011-2014 sobre la problemática de las interfaces de usuario de los catálogos en línea de acceso público (OPACs) en entorno web de las bibliotecas nacionales, universitarias, especializadas y públicas de Latinoamérica, a fin de examinar las funcionalidades propias de las áreas de control de operaciones, formulación de la búsqueda y puntos de acceso, control de salida y asistencia al usuario, así como también las funcionalidades Web 2.0. Se adopta una metodología cuantitativa. Se plantea aplicar a una muestra representada por 102 unidades, extraída por muestreo aleatorio simple (de una población compuesta por 846 casos), la lista de funcionalidades que proporciona Hildreth (1982) actualizada; comparar, mediante un diseño experimental de muestras relacionadas, las variaciones producidas en cuanto a presencia/ausencia de funcionalidades y tipo de software adoptado en relación con la situación existente ya verificada en investigaciones previas; identificar, a partir de la observación de las interfaces de los OPACs que constituyen la muestra, la presencia/ausencia de funcionalidades Web 2.0; utilizar para ello como instrumento de recolección la lista de funcionalidades deseables en los OPACs 2.0 confeccionada por Margaix-Arnal (2007); aplicar diferentes pruebas estadísticas para describir las características de la interface de usuario de los OPACs Web de la región a partir del supuesto de que ha aumentado el uso de Sistemas Integrados de Gestión Bibliotecaria y la presencia de funcionalidades en aquellas unidades que han adoptado estos sistemas, aunque carecen aún de funcionalidades 2.0.
Resumo:
El presente trabajo pretende desarrollar una guía de control (checklist) que permita evaluar la búsqueda por materia en la interfaz usuario-sistema de los catálogos en línea de bibliotecas accesibles vía Web, y probar su funcionamiento mediante la evaluación de diez interfaces de catálogos de bibliotecas argentinas, desarrollados en su mayoría en Microisis con una interfaz vía CGI para servidores Web y una interfaz de un catálogo español, desarrollado con un producto comercial altamente reconocido y difundido. Asimismo, se selecciona un método de análisis multivariante para el análisis de los resultados como una alternativa del análisis clásico por característica soportada y se evalúa su eficacia y utilidad.
Resumo:
En este ensayo reflexionamos sobre los desafíos tecnológicos, económicos, académicos y políticos que implica la edición científica en formato digital para los investigadores argentinos en Ciencias Sociales y Humanas. Basándonos en la trayectoria de la Facultad de Humanidades y Ciencias de la Educación de la Universidad Nacional de La Plata en la materia, proponemos que el trabajo interdisciplinario, el acceso abierto y la revisión por pares son los pilares fundamentales para llevar adelante una revista científica publicada en la web desde una unidad académica, es decir, desarrollada por el trabajo ad honorem de docentes-investigadores y sostenida económicamente con el presupuesto universitario
Resumo:
El presente artículo analiza la adopción y los principales usos de la plataforma Facebook por parte de las bibliotecas de tres universidades en Argentina. Luego de una revisión bibliográfica sobre la temática, se exponen los procedimientos metodológicos empleados para identificar, en primer lugar, las instituciones que cuentan con esta herramienta de comunicación en la actualidad y, en segundo término, los usos que se hace de ella a partir de una serie de variables, entre las que caben consignar: el momento de inicio, los vínculos con otros medios de comunicación administrados por la institución (webs y redes sociales), el número de seguidores, el empleo de las imágenes, la frecuencia y el tipo de posteos y, por último, la cantidad y la calidad de los comentarios. En los resultados se trabaja la información recabada procurando un análisis cuantitativo y otro cualitativo en la construcción de un panorama global. En las conclusiones se destaca la paulatina adopción de la plataforma por parte de las bibliotecas universitarias, aunque con usos limitados respecto de su potencial. Se sugieren otras posibilidades