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1.
bioRxiv ; 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38260246

RESUMO

Neural oscillations mediate the coordination of activity within and between brain networks, supporting cognition and behaviour. How these processes develop throughout childhood is not only an important neuroscientific question but could also shed light on the mechanisms underlying neurological and psychiatric disorders. However, measuring the neurodevelopmental trajectory of oscillations has been hampered by confounds from instrumentation. In this paper, we investigate the suitability of a disruptive new imaging platform - Optically Pumped Magnetometer-based magnetoencephalography (OPM-MEG) - to study oscillations during brain development. We show how a unique 192-channel OPM-MEG device, which is adaptable to head size and robust to participant movement, can be used to collect high-fidelity electrophysiological data in individuals aged between 2 and 34 years. Data were collected during a somatosensory task, and we measured both stimulus-induced modulation of beta oscillations in sensory cortex, and whole-brain connectivity, showing that both modulate significantly with age. Moreover, we show that pan-spectral bursts of electrophysiological activity drive task-induced beta modulation, and that their probability of occurrence and spectral content change with age. Our results offer new insights into the developmental trajectory of beta oscillations and provide clear evidence that OPM-MEG is an ideal platform for studying electrophysiology in neurodevelopment.

2.
Neuroimage ; 274: 120157, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37149237

RESUMO

The ability to collect high-quality neuroimaging data during ambulatory participant movement would enable a wealth of neuroscientific paradigms. Wearable magnetoencephalography (MEG) based on optically pumped magnetometers (OPMs) has the potential to allow participant movement during a scan. However, the strict zero magnetic field requirement of OPMs means that systems must be operated inside a magnetically shielded room (MSR) and also require active shielding using electromagnetic coils to cancel residual fields and field changes (due to external sources and sensor movements) that would otherwise prevent accurate neuronal source reconstructions. Existing active shielding systems only compensate fields over small, fixed regions and do not allow ambulatory movement. Here we describe the matrix coil, a new type of active shielding system for OPM-MEG which is formed from 48 square unit coils arranged on two planes which can compensate magnetic fields in regions that can be flexibly placed between the planes. Through the integration of optical tracking with OPM data acquisition, field changes induced by participant movement are cancelled with low latency (25 ms). High-quality MEG source data were collected despite the presence of large (65 cm translations and 270° rotations) ambulatory participant movements.


Assuntos
Magnetoencefalografia , Dispositivos Eletrônicos Vestíveis , Humanos , Magnetoencefalografia/métodos , Movimento , Campos Magnéticos , Fenômenos Eletromagnéticos , Encéfalo/fisiologia
3.
Int J Forecast ; 37(1): 360-377, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32836592

RESUMO

Is it possible to predict malfeasance in public procurement? With the proliferation of e-procurement systems in the public sector, anti-corruption agencies and watchdog organizations have access to valuable sources of information with which to identify transactions that are likely to become troublesome and why. In this article, we discuss the promises and challenges of using machine learning models to predict inefficiency and corruption in public procurement. We illustrate this approach with a dataset with more than two million public procurement contracts in Colombia. We trained machine learning models to predict which of them will result in corruption investigations, a breach of contract, or implementation inefficiencies. We then discuss how our models can help practitioners better understand the drivers of corruption and inefficiency in public procurement. Our approach will be useful to governments interested in exploiting large administrative datasets to improve the provision of public goods, and it highlights some of the tradeoffs and challenges that they might face throughout this process.

4.
J Clin Transl Endocrinol ; 21: 100231, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32695611

RESUMO

OBJECTIVES: Surveys for U.S. diabetes surveillance do not reliably distinguish between type 1 and type 2 diabetes, potentially obscuring trends in type 1 among adults. To validate survey-based algorithms for distinguishing diabetes type, we linked survey data collected from adult patients with diabetes to a gold standard diabetes type. RESEARCH DESIGN AND METHODS: We collected data through a telephone survey of 771 adults with diabetes receiving care in a large healthcare system in North Carolina. We tested 34 survey classification algorithms utilizing information on respondents' report of physician-diagnosed diabetes type, age at onset, diabetes drug use, and body mass index. Algorithms were evaluated by calculating type 1 and type 2 sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) relative to a gold standard diagnosis of diabetes type determined through analysis of EHR data and endocrinologist review of selected cases. RESULTS: Algorithms based on self-reported type outperformed those based solely on other data elements. The top-performing algorithm classified as type 1 all respondents who reported type 1 and were prescribed insulin, as "other diabetes type" all respondents who reported "other," and as type 2 the remaining respondents (type 1 sensitivity 91.6%, type 1 specificity 98.9%, type 1 PPV 82.5%, type 1 NPV 99.5%). This algorithm performed well in most demographic subpopulations. CONCLUSIONS: The major federal health surveys should consider including self-reported diabetes type if they do not already, as the gains in the accuracy of typing are substantial compared to classifications based on other data elements. This study provides much-needed guidance on the accuracy of survey-based diabetes typing algorithms.

5.
Cochabamba; Kipus; 3 ed.; 2005. 19 p.
Monografia em Espanhol | LILACS-Express | LIBOCS, LIBOSP | ID: biblio-1300271
6.
La Paz; OPS; mar. 2002. 39 p.
Monografia em Espanhol | LILACS, LIBOCS, LIBOSP | ID: lil-322411

RESUMO

Este documento se encuentra dividido en tres partes solo con fines didácticos. En las dos primeras partes, se describen aspectos conceptuales de la supervisión y el monitoreo aplicable a cualquier temática de salud. Constituye un recordatorio para gerentes de salud a nivel departamental y local. En la última parte, se realiza un breve reseña de la problemática de violencia intrafamiliar y doméstica ya conocida por el personal de salud) y disponible según bibliografía adjunta); y luego se presentan los instrumentos específicos para la supervisión y el monitoreo de las actividades en los procesos de prestación de servicios de salud. Ambos instrumentos son sencillos y estan referidos a aspectos básicos para la atención, prevención, tratamiento y rehabilitación de la violencia intrafamiliar y doméstica, en el marco de los instrumentos normativos ya implementados por el sector y la legislación en vigencia.


Assuntos
Humanos , Masculino , Feminino , Gestão de Recursos Humanos , Saúde Pública/tendências , Violência Doméstica , Bolívia , Monitoramento Ambiental
7.
Rev. Finlay ; Urgencias Médico Quirúrgicas(especial): 80-92, 1990.
Artigo em Espanhol | CUMED | ID: cum-19396
8.
Rev. Finlay ; Urgencias Médico Quirúrgicas: 29-32, 1990.
Artigo em Espanhol | CUMED | ID: cum-19384

Assuntos
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