1,110 research outputs found
Defragmenting Digitised Manuscripts Sources: The DMMmaps: A Unified Portal to Medieval Manuscripts
Timing of the Accreting Millisecond Pulsar XTE J1814-338
We present a precise timing analysis of the accreting millisecond pulsar XTE
J1814-338 during its 2003 outburst, observed by RXTE. A full orbital solution
is given for the first time; Doppler effects induced by the motion of the
source in the binary system were corrected, leading to a refined estimate of
the orbital period, P_orb=15388.7229(2)s, and of the projected semimajor axis,
a sini/c= 390.633(9) lt-ms. We could then investigate the spin behaviour of the
accreting compact object during the outburst. We report here a refined value of
the spin frequency (nu=314.35610879(1) Hz) and the first estimate of the spin
frequency derivative of this source while accreting (nu^dot=(-6.7 +/- 0.7)
10^(-14) Hz/s). This spin down behaviour arises when both the fundamental
frequency and the second harmonic are taken into consideration. We discuss this
in the context of the interaction between the disc and the quickly rotating
magnetosphere, at accretion rates sufficiently low to allow a threading of the
accretion disc in regions where the Keplerian velocity is slower than the
magnetosphere velocity. We also present indications of a jitter of the pulse
phases around the mean trend, which we argue results from movements of the
accreting hotspots in response to variations of the accretion rate.Comment: 7 pages, 4 figures, Accepted for publication by MNRA
Cardiomyopathies: An overview
Background: Cardiomyopathies are a heterogeneous group of pathologies characterized by structural and functional alterations of the heart. Aims: The purpose of this narrative review is to focus on the most important cardiomyopathies and their epidemiology, diagnosis, and manage-ment. Methods: Clinical trials were identified by Pubmed until 30 March 2021. The search keywords were “cardiomyopathies, sudden cardiac arrest, dilated cardiomyopathy (DCM), hypertrophic car-diomyopathy (HCM), restrictive cardiomyopathy, arrhythmogenic cardiomyopathy (ARCV), tako-tsubo syndrome”. Results: Hypertrophic cardiomyopathy (HCM) is the most common primary car-diomyopathy, with a prevalence of 1:500 persons. Dilated cardiomyopathy (DCM) has a prevalence of 1:2500 and is the leading indication for heart transplantation. Restrictive cardiomyopathy (RCM) is the least common of the major cardiomyopathies, representing 2% to 5% of cases. Arrhythmogenic cardiomyopathy (ARCV) is a pathology characterized by the substitution of the myocardium by fibrofatty tissue. Takotsubo cardiomyopathy is defined as an abrupt onset of left ventricular dysfunction in response to severe emotional or physiologic stress. Conclusion: In particular, it has been reported that HCM is the most important cause of sudden death on the athletic field in the United States. It is needless to say how important it is to know which changes in the heart due to physical activity are normal, and when they are pathological
Spin up and phase fluctuations in the timing of the accreting millisecond pulsar XTE J1807-294
We performed a timing analysis of the 2003 outburst of the accreting X-ray
millisecond pulsar XTE J1807-294 observed by RXTE. Using recently refined
orbital parameters we report for the first time a precise estimate of the spin
frequency and of the spin frequency derivative. The phase delays of the pulse
profile show a strong erratic behavior superposed to what appears as a global
spin-up trend. The erratic behavior of the pulse phases is strongly related to
rapid variations of the light curve, making it very difficult to fit these
phase delays with a simple law. As in previous cases, we have therefore
analyzed separately the phase delays of the first harmonic and of the second
harmonic of the spin frequency, finding that the phases of the second harmonic
are far less affected by the erratic behavior. In the hypothesis that the
second harmonic pulse phase delays are a good tracer of the spin frequency
evolution we give for the first time a estimation of the spin frequency
derivative in this source. The source shows a clear spin-up of Hz sec (1 confidence level). The
largest source of uncertainty in the value of the spin-up rate is given by the
uncertainties on the source position in the sky. We discuss this systematics on
the spin frequency and its derivative.Comment: 17 pages, 4 figures, Accepted by Ap
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[Factors that contributed to quit smoking]
Sixteen smokers from Porto Alegre, Rio Grando do Sul, Brazil, in abstinence for more than six months were interviewed to investigate the factors that contribute for the success in quitting smoking. Interviews were examined by Content Analysis and seven categories emerged: determination to stop smoking, support received, social restrictions to smoking, benefits related to quitting smoking, information on the problems caused by smoking, elucidating campaigns, and the use of tricks. Results show that the individual's willingness to quit smoking overwhelms other factors, and that the smoker needs a lot of determination, as well as the support of society to be able to overcome the barrier of nicotine dependence
Oxygen therapy in headache disorders: A systematic review
Background: The global active prevalence of migraines is approximately 14.7%. Oxygen therapy may reduce the use of non-steroidal anti-inflammatory drugs (NSAIDs) which often have various negative side effects. The purpose of this systematic review is to analyze the literature on the efficacy of high flow oxygen for the management of headache disorders, compared to placebo treatment. Methods: Studies were identified by PubMed, Web of Science and Scopus database from 1980 to the 30 October 2020. The search included the following terms: “oxygen therapy” and “headache” and “migraine”. Studies were included if high flow oxygen was used in the treatment of headache disorders. All selected studies were qualitatively analyzed. Results: Our literature search identified 71 studies, of which 65 were discarded and 6 were included in the meta-analysis. The random effect model did not show a pooled significant resolution of headache disorders (OR 2.08 (95% CI 0.92–4.70), p < 0.0001) in the oxygen therapy group compared to the placebo group. Conclusion: In our systematic review of six studies, there were no significant differences between high flow oxygen and placebo treatment groups
User information seeking behaviour: Perceptions and reality. An evaluation of the WHO Labresources Internet portal
Evaluation on Internet portals is a key component of any online resource development. Understanding user information seeking behaviour and user perceived behaviour is essential to obtain the full picture of user needs, online activities and draw lessons to improve the design of Internet portals to better meet user expectations. This article discusses the evaluation of a WHO Internet portal: the Labresources website. The evaluation investigates user satisfaction with the resource, usability, demographic information about users and how well they could complete specific tasks using the website and compared this with the actual online behaviour revealing a number of discrepancies. An online questionnaire was advertised on the Labresources website during the period 25 November 2005 to 20 February 2006. As the site caters to English and French speakers, the questionnaire was made available in both languages. It consisted of two sections – the first section required the participant to complete three tasks using the website whereas the second section tested user satisfaction, information needs and appropriateness of the content. Weblogs data were compared with the questionnaire results to compare user perceived and actual online behaviour. Twenty one respondents completed the online questionnaire from a total of 18 countries. This was out of a potential 60 website users among whom the questionnaire was promoted. In general, respondents were satisfied with the website layout and navigation. 61.9% of respondents listed WHO among their top 5 and a third listed the Labresources website. The number of sessions where users browse (146) the information resources is almost three times more than the number of users who search (52) the resources. Weblogs revealed most interesting results with differences between what users reported doing when completing tasks and how easy they perceived the tasks and what they actually did. Twelve respondents completed at least one task. Of the remaining nine respondents, three did visit the Labresources website from the link in the questionnaire but did not go on to complete the tasks. Only one of the twelve who completed a task reported it being difficult. Three of the respondents who didn't complete a task reported the tasks to be difficult but only one of these actually followed the link to begin the tasks in the questionnaire. This article described an evaluation study investigating user perceived and actual behaviour at the WHO Labresources Internet portal. Although the questionnaire results demonstrated general satisfaction with the resource, a combination of a weblog evaluation with the questionnaire revealed a clearer picture of the user perception of and satisfaction with the website compared to their actual activity when completing the set tasks
Evaluation of the efficacy of animal-assisted therapy based on the reality orientation therapy protocol in Alzheimer's disease patients: a pilot study.
BACKGROUND: The aim of this study was to evaluate the efficacy of animal-assisted therapy (AAT) in elderly patients affected by Alzheimer's disease based on the formal reality orientation therapy (ROT) protocol.
METHODS: Our study was carried out at an Alzheimer's centre for 6 months. A homogeneous sample (age, Mini-Mental State Examination (MMSE), 15-item Geriatric Depression Scale (GDS)) of 50 patients was selected at random and successively. Patients were divided into three groups: (i) 20 patients received a course of AAT (AAT group) based on the ROT protocol; (ii) 20 patients were engaged exclusively in activities based on the ROT group; and (iii) 10 patients (control group) participated in no stimulations. MMSE and GDS were administered at time 0 (T0 ) and time 1 (T1 ) to all three groups. Differences within groups between T0 and T1 for GDS and MMSE scores were analyzed by Student's t-test. Differences between group means were analyzed using an anova test with the Bonferroni-Dunn test for post-hoc comparisons.
RESULTS: Both the AAT group and ROT group had improved GDS scores and showed a slight improvement in terms of mood. On the GDS, the AAT group improved from 11.5 (T0 ) to 9.5 (T1 ), and the ROT group improved from 11.6 (T0 ) to 10.5 (T1 ). At the same time, a slight improvement in cognitive function, as measured by the MMSE, was observed. In the AAT group, mean MMSE was 20.2 at T0 and 21.5 at T1 , and in the ROT group, it was 19.9 at T0 and 20.0 at T1 . In the control group, the average values of both the GDS and MMSE remained unchanged. The Bonferroni-Dunn results showed statistically significant differences between groups, particularly between the AAT group and the other two (P < 0.001).
CONCLUSIONS: Pet therapy interventions based on the formal ROT protocol were effective and, compared to the ROT, provided encouraging and statistically significant results
Transferência horizontal de genes simbióticos de estirpes inoculantes de B. japonicum para estirpes de rizóbios nativas dos solos dos Cerrados.
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