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1.
Phys Rev Lett ; 126(9): 091101, 2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33750144

RESUMEN

We perform a comprehensive study of Milky Way (MW) satellite galaxies to constrain the fundamental properties of dark matter (DM). This analysis fully incorporates inhomogeneities in the spatial distribution and detectability of MW satellites and marginalizes over uncertainties in the mapping between galaxies and DM halos, the properties of the MW system, and the disruption of subhalos by the MW disk. Our results are consistent with the cold, collisionless DM paradigm and yield the strongest cosmological constraints to date on particle models of warm, interacting, and fuzzy dark matter. At 95% confidence, we report limits on (i) the mass of thermal relic warm DM, m_{WDM}>6.5 keV (free-streaming length, λ_{fs}≲10h^{-1} kpc), (ii) the velocity-independent DM-proton scattering cross section, σ_{0}<8.8×10^{-29} cm^{2} for a 100 MeV DM particle mass [DM-proton coupling, c_{p}≲(0.3 GeV)^{-2}], and (iii) the mass of fuzzy DM, m_{ϕ}>2.9×10^{-21} eV (de Broglie wavelength, λ_{dB}≲0.5 kpc). These constraints are complementary to other observational and laboratory constraints on DM properties.

2.
Child Care Health Dev ; 41(4): 505-14, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25323964

RESUMEN

Children and young people can be valuable partners in research, giving their unique perspectives on what and how research should be done. However, disabled children are less commonly involved in research than their non-disabled peers. This review investigated how disabled children have been involved as research partners; specifically how they have been recruited, the practicalities and challenges of involvement and how these have been overcome, and impacts of involvement for research, and disabled children and young people. The INVOLVE definition of involvement and the Equality and Human Rights Commission definition of disability were used. Relevant bibliographic databases were searched. Websites were searched for grey literature. Included studies had involved disabled children and young people aged 5-25 years in any study design. Reviews, guidelines, reports and other documents from the grey literature were eligible for inclusion. Twenty-two papers were included: seven reviews, eight original research papers, three reports, three guidelines and one webpage. Nine examples of involvement were identified. Recommendations included developing effective communication techniques, using flexible methods that can be adapted to needs and preferences, and ensuring that sufficient support and funding is available for researchers undertaking involvement. Positive impacts of involvement for disabled children included increased confidence, self-esteem and independence. Positive impacts for research were identified. Involving disabled children in research can present challenges; many of these can be overcome with sufficient time, planning and resources. More needs to be done to find ways to involve those with non-verbal communication. Generally, few details were reported about disabled children and young people's involvement in studies, and the quality of evidence was low. Although a range of positive impacts were identified, the majority of these were authors' opinions rather than data. There remains scope for methodological research to inform appropriate approaches to public and patient involvement in childhood disability research.


Asunto(s)
Investigación Biomédica/organización & administración , Niños con Discapacidad/psicología , Participación del Paciente/métodos , Niño , Comunicación , Humanos , Selección de Paciente
3.
Phys Rev Lett ; 108(17): 171803, 2012 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-22680853

RESUMEN

The Daya Bay Reactor Neutrino Experiment has measured a nonzero value for the neutrino mixing angle θ(13) with a significance of 5.2 standard deviations. Antineutrinos from six 2.9 GWth reactors were detected in six antineutrino detectors deployed in two near (flux-weighted baseline 470 m and 576 m) and one far (1648 m) underground experimental halls. With a 43,000 ton-GWth-day live-time exposure in 55 days, 10,416 (80,376) electron-antineutrino candidates were detected at the far hall (near halls). The ratio of the observed to expected number of antineutrinos at the far hall is R=0.940±0.011(stat.)±0.004(syst.). A rate-only analysis finds sin(2)2θ(13)=0.092±0.016(stat.)±0.005(syst.) in a three-neutrino framework.

4.
J Vet Intern Med ; 25(5): 1003-9, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21781165

RESUMEN

BACKGROUND: Cardiac magnetic resonance (CMR) is the imaging modality of choice for cardiac tumors in people. Although neoplastic pericardial effusion (PE) carries a poor prognosis, benign idiopathic pericardial effusion does not. Definitive diagnosis is critical for surgical intervention, but currently available diagnostic techniques such as echocardiography and pericardial fluid cytology often are inconclusive. HYPOTHESIS/OBJECTIVE: Describe CMR findings associated with PE and determine whether CMR aids in differentiation of benign and neoplastic causes of PE. ANIMALS: Eight client-owned dogs with PE diagnosed by transthoracic echocardiography (TTE). METHODS: CMR was performed with a 1.5 T, including dark blood, steady-state free procession cine, pre- and postcontrast T1-weighted imaging, and delayed inversion recovery prepped imaging. RESULTS: CMR confirmed a cardiac mass and supported suspected tumor type in 4 dogs with suspected hemangiosarcoma. In 1 equivocal TTE case, CMR did not demonstrate a mass, but neoplasia was later diagnosed. In another equivocal case, CMR did not demonstrate a mass but showed findings consistent with a pericardiocentesis complication. In 1 dog without evidence of cardiac neoplasia, abdominal magnetic resonance imaging identified presumptive hepatic and splenic metastases. On reevaluation of the original CMR study, the 2 equivocal cases that were interpreted as tumor negative were reassessed as tumor positive. CONCLUSIONS AND CLINICAL IMPORTANCE: CMR did not substantially improve diagnosis of cardiac tumors compared with TTE in these 8 cases, but it yielded useful descriptive information regarding extent, anatomic location, and potential tumor type and confirmed that CMR requires extensive additional training for tumor identification.


Asunto(s)
Enfermedades de los Perros/diagnóstico , Neoplasias Cardíacas/veterinaria , Imagen por Resonancia Magnética/veterinaria , Derrame Pericárdico/veterinaria , Animales , Enfermedades de los Perros/patología , Perros , Ecocardiografía/veterinaria , Neoplasias Cardíacas/complicaciones , Neoplasias Cardíacas/diagnóstico , Neoplasias Cardíacas/patología , Hemangiosarcoma/complicaciones , Hemangiosarcoma/diagnóstico , Hemangiosarcoma/patología , Hemangiosarcoma/veterinaria , Imagen por Resonancia Magnética/métodos , Miocardio/patología , Paraganglioma/complicaciones , Paraganglioma/diagnóstico , Paraganglioma/patología , Paraganglioma/veterinaria , Derrame Pericárdico/diagnóstico , Derrame Pericárdico/etiología , Derrame Pericárdico/patología
5.
Environ Sci Technol ; 45(5): 1761-72, 2011 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-21291246

RESUMEN

Our objective was to compare the effects on mental and physical wellbeing, health related quality of life and long-term adherence to physical activity, of participation in physical activity in natural environments compared with physical activity indoors. We conducted a systematic review using the following data sources: Medline, Embase, Psychinfo, GreenFILE, SportDISCUS, The Cochrane Library, Science Citation Index Expanded, Social Sciences Citation Index, Arts and Humanities Citation Index, Conference Proceedings Citation Index--Science and BIOSIS from inception to June 2010. Internet searches of relevant Web sites, hand searches of relevant journals, and the reference lists of included papers and other review papers identified in the search were also searched for relevant information. Controlled trials (randomized and nonrandomized) were included. To be eligible trials had to compare the effects of outdoor exercise initiatives with those conducted indoors and report on at least one physical or mental wellbeing outcome in adults or children. Screening of articles for inclusion, data extraction, and quality appraisal were performed by one reviewer and checked by a second with discrepancies resolved by discussion with a third if necessary. Due to the heterogeneity of identified studies a narrative synthesis was performed. Eleven trials (833 adults) were included. Most participants (6 trials; 523 adults) were young students. Study entry criteria and methods were sparsely reported. All interventions consisted of a single episode of walking or running indoors with the same activity at a similar level conducted outdoors on a separate occasion. A total of 13 different outcome measures were used to evaluate the effects of exercise on mental wellbeing, and 4 outcome measures were used to assess attitude to exercise. Most trials (n = 9) showed some improvement in mental wellbeing on one or other of the outcome measures. Compared with exercising indoors, exercising in natural environments was associated with greater feelings of revitalization and positive engagement, decreases in tension, confusion, anger, and depression, and increased energy. However, the results suggested that feelings of calmness may be decreased following outdoor exercise. Participants reported greater enjoyment and satisfaction with outdoor activity and declared a greater intent to repeat the activity at a later date. None of the identified studies measured the effects of physical activity on physical wellbeing or the effect of natural environments on exercise adherence. The hypothesis that there are added beneficial effects to be gained from performing physical activity outdoors in natural environments is very appealing and has generated considerable interest. This review has shown some promising effects on self-reported mental wellbeing immediately following exercise in nature which are not seen following the same exercise indoors. However, the interpretation and extrapolation of these findings is hampered by the poor methodological quality of the available evidence and the heterogeneity of outcome measures employed. The review demonstrates the paucity of high quality evidence on which to base recommendations and reveals an undoubted need for further research in this area. Large, well designed, longer term trials in populations who might benefit most from the potential advantages of outdoor exercise are needed to fully elucidate the effects on mental and physical wellbeing. The influence of these effects on the sustainability of physical activity initiatives also awaits investigation.


Asunto(s)
Estado de Salud , Salud Mental/estadística & datos numéricos , Actividad Motora , Recreación , Adulto , Ejercicio Físico , Humanos
6.
Int J Clin Pract ; 62(2): 325-33, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18081800

RESUMEN

BACKGROUND: People with depressive disorders or subsyndromal symptoms of depression (SSD) often use complementary and alternative therapies, including massage therapy (MT). This systematic review evaluates the evidence, from randomised clinical trials (RCTs), for the effectiveness of multiple sessions of classical European (Swedish) MT for the treatment of depression. METHODS: Eligible RCTs were identified via eight electronic databases and manual searches of references. Two reviewers independently selected trials, assessed trial quality and extracted data. RESULTS: Four RCTs met our inclusion criteria. Three of these RCTs compared MT with relaxation therapies, but provided insufficient data and analyses to contribute meaningfully to the evaluation of MT for depression. The fourth included RCT used MT as a control condition to evaluate a depression-specific acupuncture treatment. This trial provided limited evidence that, in the early stages of treatment, MT is less effective than acupuncture for treating depression, a treatment which itself is not accepted for this condition. CONCLUSIONS: Despite previous research suggesting that MT may be an effective treatment for depression, there is currently a lack of evidence to support this assertion from RCTs that have selected participants for depression or SSD.


Asunto(s)
Depresión/terapia , Trastorno Depresivo/terapia , Masaje , Terapia por Acupuntura , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Terapia por Relajación
7.
Am J Chin Med ; 35(1): 21-5, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17265547

RESUMEN

The effectiveness of acupuncture remains a controversial issue. The aim of this article is to evaluate trends over time in the development of the evidence-base of acupuncture. A comparison of two series of systematic reviews was conducted. The first related to the evidence-base in 2000, the second related to 2005. Both employed virtually the same methodology and criteria for evaluation. The results indicate that the evidence base has increased for 13 of the 26 conditions included in this comparison. For 7 indications it has become more positive (i.e. favoring acupuncture) and for 6 it had changed in the opposite direction. It is concluded, that acupuncture research is active. The emerging clinical evidence seems to imply that acupuncture is effective for some but not all conditions.


Asunto(s)
Acupuntura/tendencias , Medicina Basada en la Evidencia/tendencias , Actitud , Humanos , Literatura de Revisión como Asunto
8.
Clin Rheumatol ; 26(5): 736-8, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-16941201

RESUMEN

Back pain is the most common reason for using complementary therapies. This analysis of the trial evidence is aimed at determining whether the evidence base for or against complementary therapies for back pain is getting stronger. Two series of systematic reviews conducted with the same methodology 5 years apart were compared. The results suggest that the weight of the evidence has increased between 2000 and 2005 for a number of interventions. The direction of the evidence, however, remained unchanged for all but one therapy. We conclude that the value of complementary therapies in the management of back pain remains encouraging but not fully convincing.


Asunto(s)
Dolor de Espalda/terapia , Terapias Complementarias/tendencias , Medicina Basada en la Evidencia , Humanos
9.
Support Care Cancer ; 15(5): 565-8, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17093910

RESUMEN

AIM: The aim of this article is to compare the evidence relating to the effectiveness of complementary/alternative medicine (CAM) in palliative cancer care as it existed in 2000 and 2005. METHODS: Our comparison is based on systematic reviews using the same methodology at these two points in time. RESULTS: The results reveal a buoyant research activity in this sector. Consequently, new evidence for 19 CAM modalities has emerged between 2000 and 2005. For some treatments, the evidence is encouraging but for very few, it is as yet fully convincing. CONCLUSION: It follows that further research is warranted, particularly in areas where the data already looks encouraging.


Asunto(s)
Terapias Complementarias/estadística & datos numéricos , Medicina Basada en la Evidencia , Neoplasias/terapia , Humanos , Resultado del Tratamiento , Reino Unido
10.
IEEE Trans Inf Technol Biomed ; 5(2): 171-7, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11420995

RESUMEN

This paper gives a general overview of the telemedicine service on board airplanes, by considering the problems associated with it, the institutions that are already operating in the field, and the main projects (public and private) that are investigating in this direction. It also reports a brief discussion about the potential market and concludes with a number of issues related to such a service. Most of this information comes from the authors' active participation in several European projects that are particularly focused on telemedicine.


Asunto(s)
Aeronaves , Difusión de Innovaciones , Telemedicina , Telemedicina/legislación & jurisprudencia
11.
Stud Health Technol Inform ; 68: 302-5, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10724893

RESUMEN

The recent developments in Web technology now make it easy to create user-friendly interfaces to databases and link them to the Internet or to local Intranets. With the acceptance of this new approach one can take advantage of the opportunity to use this development to incorporate additional knowledge into the interface. Not only can this provide a more supportive interface, but it can also create the opportunity for sharing and comparing such knowledge in the future. This paper describes how this has been used to develop an interface to a database of maternity case records which incorporates a knowledge base of rules relating to care plan protocols and uses this to provide decision support to the carer. The issue of security is a serious problem and some aspects of the measures taken are discussed.


Asunto(s)
Seguridad Computacional , Técnicas de Apoyo para la Decisión , Internet , Sistemas de Registros Médicos Computarizados , Servicio de Ginecología y Obstetricia en Hospital , Interfaz Usuario-Computador , Femenino , Humanos , Recién Nacido , Planificación de Atención al Paciente , Embarazo , Programas Informáticos
12.
Contraception ; 56(5): 337-9, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9437564

RESUMEN

Uterine perforation remains the most serious complication of the intrauterine contraceptive device (IUD). It is more common in the puerperium, usually occurring at the time of insertion of a new device. Perforation may, however, also occur in the puerperium if a pre-existing device is not removed in early pregnancy or extruded at the time of delivery. The case is presented of a 30-year-old woman who became pregnant for the third time following insertion of an IUD in the puerperium of her second pregnancy. An uneventful pregnancy and delivery followed. Failure to detect the IUD at the time of delivery led to laparoscopy and laparotomy to locate the device. A colotomy was necessary to retrieve the device, which had formed a colocolic fistula. It is concluded that the puerperium remains the time of greatest risk of uterine perforation by an IUD. Although most occur at the time of insertion, this complication can also occur with a previously inserted device. Severe intra-abdominal complications may ensue if the device is not localized and removed. Laparotomy is justified if the laparoscopic removal is unsuccessful. A high degree of suspicion is necessary if serious consequences are to be avoided.


PIP: The incidence of uterine perforation following IUD insertion has been estimated as 1.2/1000 insertions. Presented is the case of a 30-year-old woman from Scotland who became pregnant for the third time following insertion of a Multiload Copper 250 device 6 weeks after the delivery of her second child, while she was still breast feeding. The IUD was not removed antenatally because the locator strings could not be visualized. The pregnancy was uncomplicated, with no gastrointestinal symptoms. Failure to detect the IUD at the time of delivery necessitated laparoscopy and laparotomy to locate the IUD and colotomy to retrieve the device. The IUD was located on the left side of the pelvis in the region of the descending colon. One arm had eroded through the full thickness of the sigmoid colon and the other had penetrated the adjacent loop of the colon, forming a colocolic fistula. This case confirms the observation that the puerperium is the time of greatest risk of IUD-caused uterine perforation. Although perforation is most common at the time of insertion, this complication also can occur with a previously placed device. Failure to localize and remove the IUD can result in severe intra-abdominal complications.


Asunto(s)
Enfermedades del Colon/etiología , Fístula Intestinal/etiología , Dispositivos Intrauterinos/efectos adversos , Adulto , Enfermedades del Colon/cirugía , Femenino , Humanos , Fístula Intestinal/cirugía , Periodo Posparto , Embarazo , Factores de Riesgo
13.
J Med Syst ; 19(1): 69-76, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7790809

RESUMEN

Migration from space medicine toward telemedicine services is described by potential application areas in highly populated and remote areas of Europe. Special emphasis is laid upon links between mobile patient monitoring and health care in remote areas. Pilot projects are described for home (mobile) monitoring of newborn infants endangered by sudden infant death (SID) and adults suffering from sleep apnoea. Health care in remote areas is described by the "TeleClinic-project" which will link national nodes for telemedicine services in several European states for the mobile European citizen. Another project describes the future potential of robotics for semiautonomous ultrasound diagnostics and for realtime interaction of remote experts with diagnostics and therapy.


Asunto(s)
Atención a la Salud/organización & administración , Difusión de Innovaciones , Salud Rural , Telemedicina/organización & administración , Adulto , Sistemas de Información en Atención Ambulatoria , Europa (Continente) , Humanos , Recién Nacido , Sistemas de Información , Monitoreo Fisiológico , Proyectos Piloto , Robótica , Sueño/fisiología , Muerte Súbita del Lactante/prevención & control
15.
Physiol Meas ; 14(3): 365-72, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8401276

RESUMEN

Foetal breathing movement (FBM) in utero has come to play an important role in foetal diagnosis. FBM may be monitored using real time ultrasound imaging of the foetus in utero. Foetal breathing activities can also be detected by monitoring maternal abdominal wall movement in the frequency range of 0.5-2.5 Hz. This paper presents a transducer which detects FBM non-invasively by monitoring maternal abdominal wall movements. Foetal heart sounds can also be monitored. The transducer presented uses piezo-electric film as the transducing medium. Results from preliminary clinical trials of prototype transducers on 10 patients are discussed.


Asunto(s)
Movimiento Fetal/fisiología , Respiración/fisiología , Femenino , Corazón Fetal/fisiología , Ruidos Cardíacos/fisiología , Humanos , Polivinilos , Embarazo , Transductores
17.
Biomed Sci Instrum ; 29: 161-8, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8329586

RESUMEN

Long term fetal heart rate variability (LFHRV) is equivalent to detrended (when the time series trend removed) indirectly derived averaged fetal heart rate (FHR) time series. Up to now LFHRV is looked for visually in FHR traces, by obstetricians and midwifes for determination of fetal condition. The detrended averaged FHR data or LFHRV data is a random correlated non-stationary (in second moment) time series. In this paper we have applied linear stochastic time series analysis technique to identify a parsimonious stochastic model, for parametric numerical representation of the random cyclical patterns observed in short 2 minutes quasi-stationary contiguous blocks of LFHRV data. The parametric estimation technique used is based upon the optimum exact Maximum likelihood estimation (which uses Kalman filtering as part of its implementation). Diagnostics performed on the residuals indicated that a second order autoregressive model is a statistically adequate model in capturing variability patterns observed in 2 minute data windows of detrended average FHR. Also through further analysis of the spectral behavior of this identified model, pseudo-periodicity (or random periodicity) which for a long time was visually detected, can now be detected via this numerical procedure.


Asunto(s)
Frecuencia Cardíaca Fetal , Modelos Cardiovasculares , Femenino , Monitoreo Fetal , Humanos , Funciones de Verosimilitud , Periodicidad , Embarazo , Procesos Estocásticos
18.
Phys Med Biol ; 36(2): 191-8, 1991 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1901171

RESUMEN

Whole-body counters in the UK have been compared using a multinuclide anthropomorphic phantom. A standard Bush phantom was modified by inserting channels into the long axis of each section. Radionuclide sources sealed in a urea-formaldehyde polymer were then inserted into the channels to simulate distributions of radioactivity in a human. The phantom was taken to 10 whole-body counters in the UK and estimates of 134Cs, 137Cs and 40K were obtained both separately and as mixtures. Results showed close agreement between the median estimates and the known activities. The technique also allowed diagnosis of particular problems in calibration for several of the counters.


Asunto(s)
Modelos Estructurales , Recuento Corporal Total/instrumentación , Calibración , Radioisótopos de Cesio/análisis , Humanos , Radioisótopos de Potasio/análisis , Recuento Corporal Total/normas
19.
IEEE Trans Biomed Eng ; 36(11): 1076-84, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2807316

RESUMEN

Fetal breathing movement (FBM) in utero may be an indicator of fetal health. This paper provides a second-by-second estimate of FBM rate. In the absence of a statistical model for the fetal breathing movement, block data structured autoregressive spectral estimation is used. The optimum tapered Burg algorithm provides a minimum variance breathing rate estimate from a short block of data. The data were recorded using a PVDF (PolyVinyliDeneFluoride) transducer which picks up maternal abdominal wall movements. A peak tracking algorithm is used to extract the fetal breathing rate. Results from these signals are presented in graphical form. Further analysis of the fetal breathing rate has revealed periodicities, similar to that observed in the fetal heart rate.


Asunto(s)
Monitoreo Fetal , Respiración/fisiología , Análisis Espectral/métodos , Algoritmos , Humanos
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