1,368 research outputs found

    Peak expiratory flow mediates the relationship between handgrip strength and timed up and go performance in elderly women, but not men

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    OBJECTIVE: The aim of the present study was to verify if there is sex difference in the associations among handgrip strength, peak expiratory flow (PEF) and timed up and go (TUG) test results. METHODS: The sample included 288 consecutive elderly men (n=93) and women (n=195). Functional capacity was measured using the TUG test, and muscle strength was measured based on handgrip. Moreover, as a measure of current health status, PEF was evaluated. Linear regression procedures were performed to analyze the relationships between handgrip and both PEF and TUG test results, with adjustment for confounders, and to identify the possible mediating role of PEF in the association between handgrip strength and TUG test results. RESULTS: In men, handgrip strength was associated with both PEF and TUG performance (p<0.01). After adjustment for PEF, the relationship between handgrip strength and TUG performance remained significant. In women, handgrip strength was also associated with both PEF and TUG performance (p<0.01). However, after adjustment for PEF, the relationship between handgrip strength and TUG performance was no longer significant. CONCLUSION: Mobility in the elderly is sex dependent. In particular, PEF mediates the relationship between handgrip strength and TUG performance in women, but not in men

    Numerical controls in an adjustment of the local positional geodetic network (LGN)

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    In the process of the foundation, expansion, modification LGN (free or fixed), based on its convenient measuring it defines coordinatepoints and others parameters of networks. The check of measurings and calculations solves by using convenient matrix relations in thenegation form. Their failure points out the incorrect measurement and calculations in the LGN

    Effects of high volume saline enemas vs no enema during labour – The N-Ma Randomised Controlled Trial [ISRCTN43153145]

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    BACKGROUND: Enemas are used during labour in obstetric settings with the belief that they reduce puerperal and neonatal infections, shorten labour duration, and make delivery cleaner for attending personnel. However, a systematic review of the literature found insufficient evidence to support the use of enemas. The objective of this RCT was to address an identified knowledge gap by determining the effect of routine enemas used during the first stage of labour on puerperal and neonatal infection rates. METHODS: Design: RCT (randomised controlled trial; randomized clinical trial). Outcomes: Clinical diagnosis of maternal or neonatal infections, labour duration, delivery types, episiotomy rates, and prescription of antibiotics Setting: Tertiary care referral hospital at the Javeriana University (Bogotá, Colombia) that attended 3170 births during study period with a caesarean section rate of 26%. Participants: 443 women admitted for delivery to the obstetrics service (February 1997 to February 1998) and followed for a month after delivery. Inclusion criteria were women with: low risk pregnancy and expected to remain in Bogotá during follow up; gestational age ≥ 36 weeks; no pelvic or systemic bacterial infection; intact membranes; cervix dilatation ≤7 cm. Intervention: 1 litre saline enema, versus no enema, allocated following a block random allocation sequence and using sealed opaque envelopes. RESULTS: Allocation provided balanced groups and 86% of the participants were followed up for one month. The overall infection rate for newborns was 21%, and 18% for women. We found no significant differences in puerperal or neonatal infection rates (Puerperal infection: 41/190 [22%] with enema v 26/182 [14%] without enema; RR 0.66 CI 95%: 0.43 to 1.03; neonatal infection 38/191 [20%] with enema v 40/179 [22%] without enema; RR 1.12, 95% CI 95% 0.76 to 1.66), and median labour time was similar between groups (515 min. with enema v 585 min. without enema; P = 0.24). Enemas didn't significantly change episiorraphy dehiscence rates (21/182 [12%] with enema v 32/190 [17%] without enema; P = 0.30). CONCLUSION: This RCT found no evidence to support routine use of enemas during labour. Although these results cannot rule out a small clinical effect, it seems unlikely that enemas will improve maternal and neonatal outcomes and provide an overall benefit

    Persistent Tn polyagglutination syndrome during febrile neutropenia: a case report and review of the literature

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    <p>Abstract</p> <p>Introduction</p> <p>Tn polyagglutination syndrome is a rare disorder that has been reported on only a few occasions in the literature, and, to the best of our knowledge, never before in the context of febrile neutropenia.</p> <p>Case presentation</p> <p>We report the case of a 26-year-old Caucasian woman who presented to our emergency department complaining of a persistent fever over the previous three days. She had a history of long-standing refractory pancytopenia with multi-lineage dysplasia and severe neutropenia, but she had rarely experienced infection. The results of a physical examination and multiple laboratory tests were unremarkable. While investigating the possible causes of the refractory, long-standing pancytopenia, the possibility of a polyagglutinable state was suggested. Blood samples were sent to the laboratory for an analysis of mixed-field seed lectin agglutination assay. A serum lectin panel confirmed the final diagnosis of Tn-activation.</p> <p>Conclusions</p> <p>We should include Tn-activation in our differential whenever we encounter cases of refractory long-standing idiopathic cytopenias and inconclusive bone marrow results displaying multi-lineage dysplasia. Novel genetic techniques have recently revealed the interesting pathophysiology of this phenomenon. The recognition and inclusion of Tn polyagglutination syndrome in our differential diagnoses has important clinical implications, given its main associated features, such as severe thrombocytopenia and neutropenia, which are usually linked to a benign clinical course and prognosis. Increased awareness of the polyagglutinable disorders will potentially decrease the need for invasive and costly medical interventions and also raises the need for monitoring of this specific sub-set of patients. In addition, the study of the expression and implications of Tn, and other similar antigens, offers a fascinating perspective for the study of its role in the diagnosis, prognosis and immunotherapy of solid tumors and hematological malignancies. The infrequency with which Tn polyagglutination syndrome is encountered, its clinical features and its pathophysiology make it a formidable diagnostic challenge.</p

    A double epidemic model for the SARS propagation

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    BACKGROUND: An epidemic of a Severe Acute Respiratory Syndrome (SARS) caused by a new coronavirus has spread from the Guangdong province to the rest of China and to the world, with a puzzling contagion behavior. It is important both for predicting the future of the present outbreak and for implementing effective prophylactic measures, to identify the causes of this behavior. RESULTS: In this report, we show first that the standard Susceptible-Infected-Removed (SIR) model cannot account for the patterns observed in various regions where the disease spread. We develop a model involving two superimposed epidemics to study the recent spread of the SARS in Hong Kong and in the region. We explore the situation where these epidemics may be caused either by a virus and one or several mutants that changed its tropism, or by two unrelated viruses. This has important consequences for the future: the innocuous epidemic might still be there and generate, from time to time, variants that would have properties similar to those of SARS. CONCLUSION: We find that, in order to reconcile the existing data and the spread of the disease, it is convenient to suggest that a first milder outbreak protected against the SARS. Regions that had not seen the first epidemic, or that were affected simultaneously with the SARS suffered much more, with a very high percentage of persons affected. We also find regions where the data appear to be inconsistent, suggesting that they are incomplete or do not reflect an appropriate identification of SARS patients. Finally, we could, within the framework of the model, fix limits to the future development of the epidemic, allowing us to identify landmarks that may be useful to set up a monitoring system to follow the evolution of the epidemic. The model also suggests that there might exist a SARS precursor in a large reservoir, prompting for implementation of precautionary measures when the weather cools down

    New prioritized value iteration for Markov decision processes

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    The problem of solving large Markov decision processes accurately and quickly is challenging. Since the computational effort incurred is considerable, current research focuses on finding superior acceleration techniques. For instance, the convergence properties of current solution methods depend, to a great extent, on the order of backup operations. On one hand, algorithms such as topological sorting are able to find good orderings but their overhead is usually high. On the other hand, shortest path methods, such as Dijkstra's algorithm which is based on priority queues, have been applied successfully to the solution of deterministic shortest-path Markov decision processes. Here, we propose an improved value iteration algorithm based on Dijkstra's algorithm for solving shortest path Markov decision processes. The experimental results on a stochastic shortest-path problem show the feasibility of our approach. © Springer Science+Business Media B.V. 2011.García Hernández, MDG.; Ruiz Pinales, J.; Onaindia De La Rivaherrera, E.; Aviña Cervantes, JG.; Ledesma Orozco, S.; Alvarado Mendez, E.; Reyes Ballesteros, A. (2012). New prioritized value iteration for Markov decision processes. Artificial Intelligence Review. 37(2):157-167. doi:10.1007/s10462-011-9224-zS157167372Agrawal S, Roth D (2002) Learning a sparse representation for object detection. In: Proceedings of the 7th European conference on computer vision. Copenhagen, Denmark, pp 1–15Bellman RE (1954) The theory of dynamic programming. Bull Amer Math Soc 60: 503–516Bellman RE (1957) Dynamic programming. Princeton University Press, New JerseyBertsekas DP (1995) Dynamic programming and optimal control. Athena Scientific, MassachusettsBhuma K, Goldsmith J (2003) Bidirectional LAO* algorithm. 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Springer, New YorkWingate D, Seppi KD (2005) Prioritization methods for accelerating MDP solvers. J Mach Learn Res 6: 851–88

    Neonates presenting with severe complications of frenotomy: a case series

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    <p>Abstract</p> <p>Introduction</p> <p>Tongue-tie or ankyloglossia is an anatomic variation in which the lingual frenulum is thick, short or tight. It may be asymptomatic, or present with complications like breast feeding difficulties or speech, dental and cosmetic problems. The treatment of this condition, where indicated, is frenotomy. This procedure usually has few or no complications. However, when it is done by untrained personnel, it may lead to life-threatening complications. This paper highlights complications that could arise from improper treatment of ankyloglossia.</p> <p>Case presentation</p> <p>Case 1 was a one-day-old male neonate, a Nigerian of Igbo ethnicity, who was admitted with bleeding from the mouth and passage of dark stools after clipping of the frenulum by a traditional birth attendant. He was severely pale and in hypovolemic shock, with a severed frenulum which was bleeding actively. His packed cell volume was 15%. He was resuscitated with intravenous fluids and a blood transfusion. The bleeding was controlled using an adrenaline pack. He also received antibiotics. He was discharged five days later.</p> <p>Case 2 was a three-day-old male neonate, a Nigerian of Ikwerre ethnicity, who was admitted with profuse bleeding from a soft tissue injury under the tongue, after clipping of the frenulum by a community health worker. He was severely pale and lethargic. He was resuscitated with intravenous fluids and a blood transfusion. The bleeding vessel was ligated with repair of the soft tissue. He also received antibiotics and was discharged home one week later.</p> <p>Conclusion</p> <p>Treatment of tongue-tie, a benign condition, when done by untrained personnel may result in life-threatening complications. Clinicians should pay more attention to parents' worries about this condition and give adequate counseling or refer them to trained personnel for surgical intervention where clinically indicated.</p

    Large Anomalous Hall effect in a silicon-based magnetic semiconductor

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    Magnetic semiconductors are attracting high interest because of their potential use for spintronics, a new technology which merges electronics and manipulation of conduction electron spins. (GaMn)As and (GaMn)N have recently emerged as the most popular materials for this new technology. While Curie temperatures are rising towards room temperature, these materials can only be fabricated in thin film form, are heavily defective, and are not obviously compatible with Si. We show here that it is productive to consider transition metal monosilicides as potential alternatives. In particular, we report the discovery that the bulk metallic magnets derived from doping the narrow gap insulator FeSi with Co share the very high anomalous Hall conductance of (GaMn)As, while displaying Curie temperatures as high as 53 K. Our work opens up a new arena for spintronics, involving a bulk material based only on transition metals and Si, and which we have proven to display a variety of large magnetic field effects on easily measured electrical properties.Comment: 19 pages with 5 figure
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