642 research outputs found

    ECG Motion Artefact Reduction Improvements of a Chest-based Wireless Patient Monitoring System

    Get PDF
    Abstract An evaluation of motion artefact for a newly CE approved wireless bodyworn monitoring device is presented. This evaluation has shown that the system under test has greatly reduced motion artefact with comparison to an FDA-approved leaded system. Analysis of physiological data, such as quality of ECG signal, accuracy of recording of heart rate, temperature and ECG R-R interval has shown the system to offer high fidelity recordings and a robust service during a range of basic movements. Presented results have shown that the average difference in heart rate between the prototype and the reference device was 3.8bpm with standard deviation of 12.4bpm. Temperature analysis indicated the average difference between the prototype and the reference device was 5.66 o C, with standard deviation of 0.44 o C. R-R interval analysis highlighted mean interval difference as 78.96ms with standard deviation of 123.1ms. In general, the user activity of bending had highest errors due to the considerable torso movement

    Upper- and mid-mantle interaction between the Samoan plume and the Tonga-Kermadec slabs

    Get PDF
    Mantle plumes are thought to play a key role in transferring heat from the core\u2013mantle boundary to the lithosphere, where it can significantly influence plate tectonics. On impinging on the lithosphere at spreading ridges or in intra-plate settings, mantle plumes may generate hotspots, large igneous provinces and hence considerable dynamic topography. However, the active role of mantle plumes on subducting slabs remains poorly understood. Here we show that the stagnation at 660 km and fastest trench retreat of the Tonga slab in Southwestern Pacific are consistent with an interaction with the Samoan plume and the Hikurangi plateau. Our findings are based on comparisons between 3D anisotropic tomography images and 3D petrological-thermo-mechanical models, which self-consistently explain several unique features of the Fiji\u2013Tonga region. We identify four possible slip systems of bridgmanite in the lower mantle that reconcile the observed seismic anisotropy beneath the Tonga slab (VSH4VSV) with thermo-mechanical calculations

    Impacts of the Tropical Pacific/Indian Oceans on the Seasonal Cycle of the West African Monsoon

    Get PDF
    The current consensus is that drought has developed in the Sahel during the second half of the twentieth century as a result of remote effects of oceanic anomalies amplified by local land–atmosphere interactions. This paper focuses on the impacts of oceanic anomalies upon West African climate and specifically aims to identify those from SST anomalies in the Pacific/Indian Oceans during spring and summer seasons, when they were significant. Idealized sensitivity experiments are performed with four atmospheric general circulation models (AGCMs). The prescribed SST patterns used in the AGCMs are based on the leading mode of covariability between SST anomalies over the Pacific/Indian Oceans and summer rainfall over West Africa. The results show that such oceanic anomalies in the Pacific/Indian Ocean lead to a northward shift of an anomalous dry belt from the Gulf of Guinea to the Sahel as the season advances. In the Sahel, the magnitude of rainfall anomalies is comparable to that obtained by other authors using SST anomalies confined to the proximity of the Atlantic Ocean. The mechanism connecting the Pacific/Indian SST anomalies with West African rainfall has a strong seasonal cycle. In spring (May and June), anomalous subsidence develops over both the Maritime Continent and the equatorial Atlantic in response to the enhanced equatorial heating. Precipitation increases over continental West Africa in association with stronger zonal convergence of moisture. In addition, precipitation decreases over the Gulf of Guinea. During the monsoon peak (July and August), the SST anomalies move westward over the equatorial Pacific and the two regions where subsidence occurred earlier in the seasons merge over West Africa. The monsoon weakens and rainfall decreases over the Sahel, especially in August.Peer reviewe

    Severe early onset preeclampsia: short and long term clinical, psychosocial and biochemical aspects

    Get PDF
    Preeclampsia is a pregnancy specific disorder commonly defined as de novo hypertension and proteinuria after 20 weeks gestational age. It occurs in approximately 3-5% of pregnancies and it is still a major cause of both foetal and maternal morbidity and mortality worldwide1. As extensive research has not yet elucidated the aetiology of preeclampsia, there are no rational preventive or therapeutic interventions available. The only rational treatment is delivery, which benefits the mother but is not in the interest of the foetus, if remote from term. Early onset preeclampsia (<32 weeks’ gestational age) occurs in less than 1% of pregnancies. It is, however often associated with maternal morbidity as the risk of progression to severe maternal disease is inversely related with gestational age at onset2. Resulting prematurity is therefore the main cause of neonatal mortality and morbidity in patients with severe preeclampsia3. Although the discussion is ongoing, perinatal survival is suggested to be increased in patients with preterm preeclampsia by expectant, non-interventional management. This temporising treatment option to lengthen pregnancy includes the use of antihypertensive medication to control hypertension, magnesium sulphate to prevent eclampsia and corticosteroids to enhance foetal lung maturity4. With optimal maternal haemodynamic status and reassuring foetal condition this results on average in an extension of 2 weeks. Prolongation of these pregnancies is a great challenge for clinicians to balance between potential maternal risks on one the eve hand and possible foetal benefits on the other. Clinical controversies regarding prolongation of preterm preeclamptic pregnancies still exist – also taking into account that preeclampsia is the leading cause of maternal mortality in the Netherlands5 - a debate which is even more pronounced in very preterm pregnancies with questionable foetal viability6-9. Do maternal risks of prolongation of these very early pregnancies outweigh the chances of neonatal survival? Counselling of women with very early onset preeclampsia not only comprises of knowledge of the outcome of those particular pregnancies, but also knowledge of outcomes of future pregnancies of these women is of major clinical importance. This thesis opens with a review of the literature on identifiable risk factors of preeclampsia

    Penilaian Kinerja Keuangan Koperasi di Kabupaten Pelalawan

    Full text link
    This paper describe development and financial performance of cooperative in District Pelalawan among 2007 - 2008. Studies on primary and secondary cooperative in 12 sub-districts. Method in this stady use performance measuring of productivity, efficiency, growth, liquidity, and solvability of cooperative. Productivity of cooperative in Pelalawan was highly but efficiency still low. Profit and income were highly, even liquidity of cooperative very high, and solvability was good

    Hypnosis for treatment of insomnia in school-age children: a retrospective chart review

    Get PDF
    BACKGROUND: The purposes of this study are to document psychosocial stressors and medical conditions associated with development of insomnia in school-age children and to report use of hypnosis for this condition. METHODS: A retrospective chart review was performed for 84 children and adolescents with insomnia, excluding those with central or obstructive sleep apnea. All patients were offered and accepted instruction in self-hypnosis for treatment of insomnia, and for other symptoms if it was felt that these were amenable to therapy with hypnosis. Seventy-five patients returned for follow-up after the first hypnosis session. Their mean age was 12 years (range, 7–17). When insomnia did not resolve after the first instruction session, patients were offered the opportunity to use hypnosis to gain insight into the cause. RESULTS: Younger children were more likely to report that the insomnia was related to fears. Two or fewer hypnosis sessions were provided to 68% of the patients. Of the 70 patients reporting a delay in sleep onset of more than 30 minutes, 90% reported a reduction in sleep onset time following hypnosis. Of the 21 patients reporting nighttime awakenings more than once a week, 52% reported resolution of the awakenings and 38% reported improvement. Somatic complaints amenable to hypnosis were reported by 41%, including chest pain, dyspnea, functional abdominal pain, habit cough, headaches, and vocal cord dysfunction. Among these patients, 87% reported improvement or resolution of the somatic complaints following hypnosis. CONCLUSION: Use of hypnosis appears to facilitate efficient therapy for insomnia in school-age children

    Functional Diffusion Tensor Imaging: Measuring Task-Related Fractional Anisotropy Changes in the Human Brain along White Matter Tracts

    Get PDF
    Functional neural networks in the human brain can be studied from correlations between activated gray matter regions measured with fMRI. However, while providing important information on gray matter activation, no information is gathered on the co-activity along white matter tracts in neural networks.We report on a functional diffusion tensor imaging (fDTI) method that measures task-related changes in fractional anisotropy (FA) along white matter tracts. We hypothesize that these fractional anisotropy changes relate to morphological changes of glial cells induced by axonal activity although the exact physiological underpinnings of the measured FA changes remain to be elucidated. As expected, these changes are very small as compared to the physiological noise and a reliable detection of the signal change would require a large number of measurements. However, a substantial increase in signal-to-noise ratio was achieved by pooling the signal over the complete fiber tract. Adopting such a tract-based statistics enabled us to measure the signal within a practically feasible time period. Activation in the sensory thalamocortical tract and optic radiation in eight healthy human subjects was found during tactile and visual stimulation, respectively.The results of our experiments indicate that these FA changes may serve as a functional contrast mechanism for white matter. This noninvasive fDTI method may provide a new approach to study functional neural networks in the human brain
    corecore