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1.
Health Educ Res ; 35(5): 396-406, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32772070

RESUMEN

Effective obesity interventions in adolescent populations have been identified as an immediate priority action to stem the increasing prevalence of adult obesity. The purpose of this meta-analysis was to make a quantitative analysis of the impact of school-based interventions on body mass index during adolescence. Studies were retrieved from PubMed, Scopus, Science Direct and Web of Science databases. Results were pooled using a random-effects model with 95% confidence interval considered statistically significant. Of the 18 798 possible relevant articles identified, 12 articles were included in this meta-analysis. The global result showed a low magnitude effect, though it was statistically significant (N = 14 428), global e.s. = -0.055, P = 0.004 (95% CI = -0.092, -0.017). Heterogeneity was low among the studies (I2 = 9.017%). The funnel plot showed no evidence of publication bias. The rank-correlation test of Begg (P = 0.45641) and Egger's regression (P = 0.19459) confirmed the absence of bias. This meta-analysis reported a significant effect favoring the interventions; however, future research are needed since the reported the evidence was of low magnitude, with the studies following a substantial range of approaches and mostly had a modest methodological quality.


Asunto(s)
Instituciones Académicas , Adolescente , Índice de Masa Corporal , Humanos , Prevalencia
2.
In Silico Biol ; 14(1-2): 101-121, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32597796

RESUMEN

A dynamical model of the pathophysiological behaviors of IL18 and IL10 cytokines with their receptors is tested against data for the case of early sepsis. The proposed approach considers the surroundings (organs and bone marrow) and the different subsystems (cells and cyctokines). The interactions between blood cells, cytokines and the surroundings are described via mass balances. Cytokines are adsorbed onto associated receptors at the cell surface. The adsorption is described by the Langmuir model and gives rise to the production of more cytokines and associated receptors inside the cell. The quantities of pro and anti-inflammatory cytokines present in the body are combined to give global information via an inflammation level function which describes the patient's state. Data for parameter estimation comes from the Sepsis 48 H database. Comparisons between patient data and simulations are presented and are in good agreement. For the IL18/IL10 cytokine pair, 5 key parameters have been found. They are linked to pro-inflammatory IL18 cytokine and show that the early sepsis is driven by components of inflammatory character.


Asunto(s)
Adyuvantes Inmunológicos/uso terapéutico , Citocinas/inmunología , Sepsis/tratamiento farmacológico , Adyuvantes Inmunológicos/farmacología , Antiinflamatorios/uso terapéutico , Citocinas/metabolismo , Citocinas/uso terapéutico , Femenino , Humanos , Inflamación , Interleucina-10/metabolismo , Interleucina-18/metabolismo , Masculino , Modelos Inmunológicos , Sepsis/inmunología , Sepsis/metabolismo , Choque Séptico/tratamiento farmacológico , Choque Séptico/inmunología , Choque Séptico/metabolismo , Resultado del Tratamiento
3.
Clin Transl Oncol ; 21(5): 621-629, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30341474

RESUMEN

PURPOSE: The third most frequently diagnosed cancer in Europe in 2018 was lung cancer; it is also the leading cause of cancer death in Europe. We studied patient and tumor characteristics, and patterns of healthcare provision explaining regional variability in lung cancer survival in southern Spain. METHODS: A population-based cohort study included all 1196 incident first invasive primary lung cancer (C33-C34 according to ICD-10) cases diagnosed between 2010 and 2011 with follow-up until April 2015. Data were drawn from local population-based cancer registries and patients' hospital medical records from all public and private hospitals from two regions in southern Spain. RESULTS: There was evidence of regional differences in lung cancer late diagnosis (58% stage IV in Granada vs. 65% in Huelva, p value < 0.001). Among patients with stage I, only 67% received surgery compared with 0.6% of patients with stage IV. Patients treated with a combination of radiotherapy, chemotherapy, and surgery had a 2-year mortality risk reduction of 94% compared with patients who did not receive any treatment (excess mortality risk 0.06; 95% CI 0.02-0.16). Geographical differences in survival were observed between the two regions: 35% vs. 26% at 1-year since diagnosis. CONCLUSIONS: The observed geographic differences in survival between regions are due in part to the late cancer diagnosis which determines the use of less effective therapeutic options. Results from our study justify the need for promoting lung cancer early detection strategies and the harmonization of the best practice in lung cancer management and treatment.


Asunto(s)
Detección Precoz del Cáncer/mortalidad , Servicios de Salud , Disparidades en Atención de Salud , Neoplasias Pulmonares/mortalidad , Sistema de Registros/estadística & datos numéricos , Adolescente , Adulto , Anciano , Estudios de Cohortes , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/terapia , Masculino , Persona de Mediana Edad , Pronóstico , Factores de Riesgo , España/epidemiología , Tasa de Supervivencia , Adulto Joven
4.
Sci Rep ; 8(1): 14463, 2018 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-30262898

RESUMEN

Recently, we showed that the self-field transport critical current, Ic(sf), of a superconducting wire can be defined in a more fundamental way than the conventional (and arbitrary) electric field criterion, Ec = 1 µV/cm. We defined Ic(sf) as the threshold current, Ic,B, at which the perpendicular component of the local magnetic flux density, B⊥, measured at any point on the surface of a high-temperature superconducting tape abruptly crosses over from a non-linear to a linear dependence with increasing transport current. This effect results from the current distribution across the tape width progressively transitioning from non-uniform to uniform. The completion of this progressive transition was found to be singular. It coincides with the first discernible onset of dissipation and immediately precedes the formation of a measureable electric field. Here, we show that the same Ic,B definition of critical currents applies in the presence of an external applied magnetic field, Ba. In all experimental data presented here Ic,B is found to be significantly (10-30%) lower than Ic,E determined by the common electric field criterion of Ec = 1 µV/cm, and Ec to be up to 50 times lower at Ic,B than at Ic,E.

5.
Sci Rep ; 8(1): 1716, 2018 01 29.
Artículo en Inglés | MEDLINE | ID: mdl-29379094

RESUMEN

The current distribution across the thickness of a current-carrying rectangular film in the Meissner state was established long ago by the London brothers. The distribution across the width is more complicated but was later shown to be highly non-uniform, diverging at the edges. Accordingly, the standard view for type II superconductors is that vortices enter at the edges and, with increasing current, are driven inwards until they self-annihilate at the centre, causing dissipation. This condition is presumed to define the critical current. However we have shown that, under self-field (no external field), the transport critical current is a London surface current where the surface current density equals the critical field divided by λ, across the entire width. The critical current distribution must therefore be uniform. Here we report studies of the current and field distribution across commercial YBa2Cu3 O7 conductors and confirm the accepted non-uniform distribution at low current but demonstrate a radical crossover to a uniform distribution at critical current. This crossover ends discontinuously at a singularity and calculations quantitatively confirm these results in detail. The onset of self-field dissipation is, unexpectedly, thermodynamic in character and the implied vortex-free critical state seems to require new physics.

6.
Sci Rep ; 7(1): 10010, 2017 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-28855601

RESUMEN

Universal scaling behaviour in superconductors has significantly elucidated fluctuation and phase transition phenomena in these materials. However, universal behaviour for the most practical property, the critical current, was not contemplated because prevailing models invoke nucleation and migration of flux vortices. Such migration depends critically on pinning, and the detailed microstructure naturally differs from one material to another, even within a single material. Through microstructural engineering there have been ongoing improvements in the field-dependent critical current, thus illustrating its non-universal behaviour. But here we demonstrate the universal size scaling of the self-field critical current for any superconductor, of any symmetry, geometry or band multiplicity. Key to our analysis is the huge range of sample dimensions, from single-atomic-layer to mm-scale. These have widely variable microstructure with transition temperatures ranging from 1.2 K to the current record, 203 K. In all cases the critical current is governed by a fundamental surface current density limit given by the relevant critical field divided by the penetration depth.

7.
Nat Commun ; 6: 7820, 2015 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-26240014

RESUMEN

For any practical superconductor the magnitude of the critical current density, Jc, is crucially important. It sets the upper limit for current in the conductor. Usually Jc falls rapidly with increasing external magnetic field, but even in zero external field the current flowing in the conductor generates a self-field that limits Jc. Here we show for thin films of thickness less than the London penetration depth, λ, this limiting Jc adopts a universal value for all superconductors-metals, oxides, cuprates, pnictides, borocarbides and heavy Fermions. For type-I superconductors, it is Hc/λ where Hc is the thermodynamic critical field. But surprisingly for type-II superconductors, we find the self-field Jc is Hc1/λ where Hc1 is the lower critical field. Jc is thus fundamentally determined and this provides a simple means to extract absolute values of λ(T) and, from its temperature dependence, the symmetry and magnitude of the superconducting gap.

8.
CJEM ; 16(3): 207-13, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24852583

RESUMEN

OBJECTIVE: Despite evidence that patients suffering major traumatic injuries have improved outcomes when cared for within an organized system, the extent of trauma system development in Canada is limited. We sought to compile a detailed inventory of trauma systems in Canada as a first step toward identifying opportunities for improving access to trauma care. METHODS: We distributed a nationwide online and mail survey to stakeholders intended to evaluate the extent of implementation of specific trauma system components. Targeted stakeholders included emergency physicians, trauma surgeons, trauma program medical directors and program managers, prehospital providers, and decision makers at the regional and provincial levels. A "snowball" approach was used to expand the sample base of the survey. Descriptive statistics were generated to quantify the nature and extent of trauma system development by region. RESULTS: The overall response rate was 38.7%, and all levels of stakeholders and all provinces/territories were represented. All provinces were found to have designated trauma centres; however, only 60% were found to have been accredited within the past 10 years. Components present in 50% or fewer provinces included an inclusive trauma system model, interfacility transfer agreements, and a mechanism to track bed availability within the system. CONCLUSION: There is significant variability in the extent of trauma system development in Canada. Although all provinces have designated trauma centres, opportunities exist in many systems to implement additional components to improve the inclusiveness of care. In future work, we intend to quantify the strength of the relationship between different trauma system components and access to definitive trauma care.


Asunto(s)
Internet , Encuestas y Cuestionarios , Centros Traumatológicos/organización & administración , Canadá , Estudios Transversales , Humanos
9.
Clin Microbiol Infect ; 19(7): 620-7, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22900572

RESUMEN

Methicillin resistant Staphylococcus aureus (MRSA) infection can cause significant morbidity and mortality in neonates. We investigated a nosocomial MRSA outbreak in a neonatal intensive care unit (NICU), using a novel typing method. Following two fatal cases, in May 2011, a prospective outbreak investigation was conducted, involving neonates, mothers and healthcare workers in a large tertiary NICU in Sydney. MRSA isolates were characterized by antimicrobial susceptibility testing, a multiplex PCR-based reverse line blot (mPCR/RLB) binary typing system and other molecular typing methods. Over 7 months, 14 neonates were colonized with MRSA and six infected: three with superficial lesions and three with life-threatening disease, including the two index cases, who died despite empirical treatment with vancomycin. Isolates from 15 neonates were indistinguishable by RLB typing and identified as a PVL-producing ST22 SCCmec IV MRSA strain, which was resistant to gentamicin and trimethoprim-sulphamethoxazole. The outbreak strain was also isolated from one healthcare worker, one environmental swab and one father, but the source remained obscure. During the same period several different non-multiresistant and multiresistant MRSA strains were isolated from five neonates, five mothers (including two whose infants were colonized with the outbreak strain), one father, three healthcare workers and two environmental swabs. Rapid turnaround time of typing results allowed us to recognize and define the outbreak and implement targeted infection control interventions. PVL-producing ST22 SCCmec IV MRSA appears to be a virulent and highly transmissible pathogen in the NICU, which was difficult to control.


Asunto(s)
Infección Hospitalaria/epidemiología , Brotes de Enfermedades , Control de Infecciones/métodos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Infecciones Estafilocócicas/epidemiología , Australia/epidemiología , Toxinas Bacterianas/genética , Infección Hospitalaria/microbiología , Exotoxinas/genética , Femenino , Genotipo , Humanos , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Leucocidinas/genética , Masculino , Staphylococcus aureus Resistente a Meticilina/clasificación , Staphylococcus aureus Resistente a Meticilina/genética , Pruebas de Sensibilidad Microbiana , Epidemiología Molecular , Tipificación Molecular , Infecciones Estafilocócicas/microbiología , Factores de Virulencia/genética
10.
Phys Rev Lett ; 111(23): 237001, 2013 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-24476299

RESUMEN

We suggest, and demonstrate, a systematic approach to the study of cuprate superconductors, namely, progressive change of ion size in order to systematically alter the interaction strength and other key parameters. R(Ba,Sr)2Cu3Oy (R={La,…,Lu,Y}) is such a system where potentially obscuring structural changes are minimal. We thereby systematically alter both dielectric and magnetic properties. Dielectric fluctuation is characterized by ionic polarizability while magnetic fluctuation is characterized by exchange interactions measurable by Raman scattering. The range of transition temperatures is 70-107 K, and we find that these correlate only with the dielectric properties, a behavior which persists with external pressure. The ultimate significance may remain to be proven, but it highlights the role of dielectric screening in the cuprates and adds support to a previously proposed novel pairing mechanism involving exchange of quantized waves of electronic polarization.

11.
Phys Rev Lett ; 106(4): 047006, 2011 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-21405352

RESUMEN

We show that a multilayer analysis of the infrared c-axis response of RBa2Cu3O(7-δ) (R=Y, Gd, Eu) provides important new information about the anomalous normal-state properties of underdoped cuprate high temperature superconductors. In addition to competing correlations which give rise to a pseudogap that depletes the low-energy electronic states below T*≫T(c), it enables us to identify the onset of a precursor superconducting state below T(ons)>T(c). We map out the doping phase diagram of T(ons) which reaches a maximum of 180 K at strong underdoping and present magnetic field dependent data which confirm our conclusions.

12.
Phys Rev E Stat Nonlin Soft Matter Phys ; 76(6 Pt 2): 066306, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18233916

RESUMEN

The composite torsional ultrasonic oscillator, a versatile experimental system, can be used to investigate slip of a Newtonian fluid at a smooth surface. A rigorous analysis of slip-dependent damping for the oscillator is presented. Initially, the phenomenon of finite surface slip and the slip length are considered for a half space of Newtonian fluid in contact with a smooth, oscillating solid surface. Definitions are reconsidered and clarified in light of inconsistencies in the literature. We point out that, in general oscillating flows, Navier's slip length b is a complex number. An intuitive velocity discontinuity parameter of unrestricted phase is used to describe the effect of slip on measurement of viscous shear damping. The analysis is applied to the composite oscillator, and preliminary experimental work for a 40 kHz oscillator is presented. The nonslip boundary condition has been verified for a hydrophobic surface in water to within approximately 60 nm of |b|=0 nm . Experiments were carried out at shear rate amplitudes between 230 and 6800 s(-1), corresponding to linear displacement amplitudes between 3.2 and 96 nm.

13.
Phys Rev Lett ; 94(22): 227003, 2005 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-16090428

RESUMEN

The influence of magnetic Ni and nonmagnetic Zn impurities on the normal-state pseudogap (PG) in the c-axis optical conductivity of (Sm,Nd)Ba(2){Cu(1-y)(Ni,Zn)(y)}(3)O(7-delta) crystals was studied by spectral ellipsometry. We find that these impurities, which strongly suppress superconductivity, have a profoundly different impact on the PG. Zn gives rise to a gradual and inhomogeneous PG suppression while Ni strongly enhances the PG. Our results challenge theories that relate the PG either to precursor superconductivity or to other phases with exotic order parameters, such as flux phase or d-density wave states, that should be suppressed by potential scattering. The apparent difference between magnetic and nonmagnetic impurities instead points towards an important role of magnetic correlations in the PG state.

14.
Phys Rev Lett ; 94(23): 237002, 2005 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-16090497

RESUMEN

Underdoped cuprates exhibit a normal-state pseudogap, and their spins and doped carriers tend to spatially separate into 1D or 2D stripes. Some view these as central to superconductivity and others as peripheral and merely competing. Using La(2-x)Sr(x)Cu(1-y)Zn(y)O4 we show that an oxygen isotope effect in Tc and in the superfluid density can be used to distinguish between the roles of stripes and pseudogap and also to detect the presence of impurity scattering. We conclude that stripes and pseudogap are distinct, and both compete and coexist with superconductivity.

15.
16.
Phys Rev Lett ; 86(8): 1614-7, 2001 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-11290206

RESUMEN

The doping dependence of the ratio of the superconducting condensate density to the effective mass, n(o)(s)/m(*)(ab), was studied in detail by muon-spin rotation for Y(0.8)Ca(0.2)Ba(2)(Cu(1-z)Zn(z))(3)O(7-delta) and Tl(0.5-y)Pb(0.5+y)Sr(2)Ca(1-x)Y(x)Cu(2)O(7). Our data show that n(o)(s)/m(*)(ab) exhibits a peak at a unique doping state in the overdoped regime. Its position coincides with the critical doping state, where the normal state pseudogap was reported to appear and to deplete the electronic density of states. This finding implies that the pseudogap primarily arises from a change in the electronic ground state rather than from thermal fluctuations.

17.
CMAJ ; 162(9): 1276-7, 2000 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-10813007
18.
Actas Urol Esp ; 24(10): 832-5, 2000.
Artículo en Español | MEDLINE | ID: mdl-11199303

RESUMEN

Testicular microlithiasis is a rare condition usually diagnosed by scrotal ultrasound and associated with pathology of the testis. We report two pediatric cases presented with acute scrotum. Testicular sonography revealed significant bilateral testicular microlithiasis. One case was diagnosed as having torsion of the right testis and the other case as orchiepididymitis. A careful review of the literature is made and a periodic follow-up of this disease is advocated.


Asunto(s)
Cálculos/diagnóstico , Cálculos/terapia , Enfermedades Testiculares/diagnóstico , Enfermedades Testiculares/terapia , Niño , Humanos , Masculino
20.
CJEM ; 1(2): 115-6, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17659118

RESUMEN

A 37-year-old man with type I diabetes mellitus and chronic renal failure presented to the emergency department complaining of hallucinations. He was 5 days postoperative for left pars plana vitrectomy and intra-ocular lens implantation and had been taking ophthalmic atropine, tobramycin and prednisolone. He had presented 5 months earlier, on the same ophthalmic medications, with postoperative hallucinations after a right pars plana vitrectomy. Visual hallucinations are a major side effect of anticholinergic poisoning. Ophthalmic instillation of atropine has been documented to cause many central nervous sytstem symptoms, including hallucinations.

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