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We show, for the first time, radio measurements of the depth of shower maximum (X_{max}) of air showers induced by cosmic rays that are compared to measurements of the established fluorescence method at the same location. Using measurements at the Pierre Auger Observatory we show full compatibility between our radio and the previously published fluorescence dataset, and between a subset of air showers observed simultaneously with both radio and fluorescence techniques, a measurement setup unique to the Pierre Auger Observatory. Furthermore, we show radio X_{max} resolution as a function of energy and demonstrate the ability to make competitive high-resolution X_{max} measurements with even a sparse radio array. With this, we show that the radio technique is capable of cosmic-ray mass composition studies, both at Auger and at other experiments.
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Instantons, which are nonperturbative solutions to Yang-Mills equations, provide a signal for the occurrence of quantum tunneling between distinct classes of vacua. They can give rise to decays of particles otherwise forbidden. Using data collected at the Pierre Auger Observatory, we search for signatures of such instanton-induced processes that would be suggestive of super-heavy particles decaying in the Galactic halo. These particles could have been produced during the post-inflationary epoch and match the relic abundance of dark matter inferred today. The nonobservation of the signatures searched for allows us to derive a bound on the reduced coupling constant of gauge interactions in the dark sector: α_{X}â²0.09, for 10^{9}â²M_{X}/GeV<10^{19}. Conversely, we obtain that, for instance, a reduced coupling constant α_{X}=0.09 excludes masses M_{X}â³3×10^{13} GeV. In the context of dark matter production from gravitational interactions alone, we illustrate how these bounds are complementary to those obtained on the Hubble rate at the end of inflation from the nonobservation of tensor modes in the cosmological microwave background.
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Experiments and numerical simulations are described that develop quantitative understanding of atomic motion near the surfaces of nanoscopic photonic crystal waveguides (PCWs). Ultracold atoms are delivered from a moving optical lattice into the PCW. Synchronous with the moving lattice, transmission spectra for a guided-mode probe field are recorded as functions of lattice transport time and frequency detuning of the probe beam. By way of measurements such as these, we have been able to validate quantitatively our numerical simulations, which are based upon detailed understanding of atomic trajectories that pass around and through nanoscopic regions of the PCW under the influence of optical and surface forces. The resolution for mapping atomic motion is roughly 50 nm in space and 100 ns in time. By introducing auxiliary guided-mode (GM) fields that provide spatially varying AC Stark shifts, we have, to some degree, begun to control atomic trajectories, such as to enhance the flux into the central vacuum gap of the PCW at predetermined times and with known AC Stark shifts. Applications of these capabilities include enabling high fractional filling of optical trap sites within PCWs, calibration of optical fields within PCWs, and utilization of the time-dependent, optically dense atomic medium for novel nonlinear optical experiments.
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We present the first measurement of the fluctuations in the number of muons in extensive air showers produced by ultrahigh energy cosmic rays. We find that the measured fluctuations are in good agreement with predictions from air shower simulations. This observation provides new insights into the origin of the previously reported deficit of muons in air shower simulations and constrains models of hadronic interactions at ultrahigh energies. Our measurement is compatible with the muon deficit originating from small deviations in the predictions from hadronic interaction models of particle production that accumulate as the showers develop.
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We report a measurement of the energy spectrum of cosmic rays above 2.5×10^{18} eV based on 215 030 events. New results are presented: at about 1.3×10^{19} eV, the spectral index changes from 2.51±0.03(stat)±0.05(syst) to 3.05±0.05(stat)±0.10(syst), evolving to 5.1±0.3(stat)±0.1(syst) beyond 5×10^{19} eV, while no significant dependence of spectral features on the declination is seen in the accessible range. These features of the spectrum can be reproduced in models with energy-dependent mass composition. The energy density in cosmic rays above 5×10^{18} eV is [5.66±0.03(stat)±1.40(syst)]×10^{53} erg Mpc^{-3}.
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Arginase 1 (ARG1) and arginase 2 (ARG2) compete with nitric oxide synthases for the substrate l-arginine. Here we aim to assess whether arginase 1 and 2 plasma levels, plasma arginase activity or genetic factors are associated with altered responsiveness to sildenafil. We studied 71 post-prostatectomy erectile dysfunction (ED) patients (PED group) and 72 clinical ED patients (CED). Patients responded to the International Index of Erectile Function questionnaire before and after the treatment. We found positive and negative correlations between plasma levels of arginase 1 and sildenafil responsiveness in the PED and CED groups, respectively. PED group also presented negative correlation between plasma arginase activity and sildenafil responsiveness. Sildenafil poor responders have shown higher plasma arginase activity in PED and higher arginase 1 levels on CED groups. In addition, variant genotypes for the rs2781659, rs2781667 and rs17599586 polymorphisms were associated with reduced arginase activity, as well as the GTTT ARG1 haplotype in CED group.
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Arginase/sangue , Arginase/genética , Disfunção Erétil/sangue , Disfunção Erétil/genética , Citrato de Sildenafila/sangue , Vasodilatadores/sangue , Adulto , Idoso , Arginase/antagonistas & inibidores , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Disfunção Erétil/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético/genética , Citrato de Sildenafila/farmacologia , Citrato de Sildenafila/uso terapêutico , Resultado do Tratamento , Vasodilatadores/farmacologia , Vasodilatadores/uso terapêuticoRESUMO
BACKGROUND: Schizotypal traits are considered a phenotypic-indicator of schizotypy, a latent personality organization reflecting a putative liability for psychosis. To date, no previous study has examined the comparability of factorial structures across samples originating from different countries and cultures. The main goal was to evaluate the factorial structure and reliability of the Schizotypal Personality Questionnaire (SPQ) scores by amalgamating data from studies conducted in 12 countries and across 21 sites. METHOD: The overall sample consisted of 27 001 participants (37.5% males, n = 4251 drawn from the general population). The mean age was 22.12 years (s.d. = 6.28, range 16-55 years). The SPQ was used. Confirmatory factor analysis (CFA) and Multilevel CFA (ML-CFA) were used to evaluate the factor structure underlying the SPQ scores. RESULTS: At the SPQ item level, the nine factor and second-order factor models showed adequate goodness-of-fit. At the SPQ subscale level, three- and four-factor models displayed better goodness-of-fit indices than other CFA models. ML-CFA showed that the intraclass correlation coefficients values were lower than 0.106. The three-factor model showed adequate goodness of fit indices in multilevel analysis. The ordinal α coefficients were high, ranging from 0.73 to 0.94 across individual samples, and from 0.84 to 0.91 for the combined sample. CONCLUSIONS: The results are consistent with the conceptual notion that schizotypal personality is a multifaceted construct and support the validity and utility of SPQ in cross-cultural research. We discuss theoretical and clinical implications of our results for diagnostic systems, psychosis models and cross-national mental health strategies.
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Inventário de Personalidade , Psicometria/estatística & dados numéricos , Transtorno da Personalidade Esquizotípica/diagnóstico , Transtorno da Personalidade Esquizotípica/psicologia , Adolescente , Adulto , Análise Fatorial , Feminino , Humanos , Internacionalidade , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Inquéritos e Questionários , Adulto JovemRESUMO
Neoplasm history increases morbidity and mortality after solid organ transplantation and has disqualified patients from transplantation. Studies are needed to identify factors to be considered when deciding on the suitability of a patient with previous tumor for heart transplantation. A retrospective epidemiological study was conducted in heart transplant (HT) recipients (Spanish Post-Heart Transplant Tumor Registry) comparing the epidemiological data, immu-nosuppressive treatments and incidence of post-HT tumors between patients with previous malignant noncardiac tumor and with no previous tumor (NPT). The impact of previous tumor (PT) on overall survival (OS) was also assessed. A total of 4561 patients, 77 PT and 4484 NPT, were evaluated. The NPT group had a higher proportion of men than the PT group (p < 0.001). The incidence of post-HT tumors was 1.8 times greater in the PT group (95% confidence interval [CI] 1.2-2.6; p < 0.001), mainly due to the increased risk in patients with a previous hematologic tumor (rate ratio 2.3, 95% CI 1.3-4.0, p < 0.004). OS during the 10-year posttransplant period was significantly lower in the PT than the NPT group (p = 0.048) but similar when the analysis was conducted after a first post-HT tumor was diagnosed. In conclusion, a history of PT increases the incidence of post-HT tumors and should be taken into account when considering a patient for HT.
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Cardiopatias/complicações , Transplante de Coração/efeitos adversos , Neoplasias/epidemiologia , Neoplasias/fisiopatologia , Complicações Pós-Operatórias/epidemiologia , Idoso , Feminino , Seguimentos , Cardiopatias/cirurgia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Espanha/epidemiologia , Fatores de TempoRESUMO
Ultrahigh energy cosmic ray air showers probe particle physics at energies beyond the reach of accelerators. Here we introduce a new method to test hadronic interaction models without relying on the absolute energy calibration, and apply it to events with primary energy 6-16 EeV (E_{CM}=110-170 TeV), whose longitudinal development and lateral distribution were simultaneously measured by the Pierre Auger Observatory. The average hadronic shower is 1.33±0.16 (1.61±0.21) times larger than predicted using the leading LHC-tuned models EPOS-LHC (QGSJetII-04), with a corresponding excess of muons.
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We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8±0.7(stat)±6.7(syst) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principles calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.
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We gathered from the literature 47 odor and 37 trigeminal (nasal and ocular) chemesthetic psychometric (i.e., detectability or dose-response) functions from a group of 41 chemicals. Vapors delivered were quantified by analytical methods. All functions were very well fitted by the sigmoid (logistic) equation: y = 1 / (1 + e({-(x-C)/D})), where parameter C quantifies the detection threshold concentration and parameter D the steepness of the function. Odor and chemesthetic functions showed no concentration overlap: olfactory functions grew along the parts per billion (ppb by volume) range or lower, whereas trigeminal functions grew along the part per million (ppm by volume) range. Although, on average, odor detectability rose from chance detection to perfect detection within 2 orders of magnitude in concentration, chemesthetic detectability did it within one. For 16 compounds having at least 1 odor and 1 chemesthetic function, the average gap between the 2 functions was 4.6 orders of magnitude in concentration. A quantitative structure-activity relationship (QSAR) using 5 chemical descriptors that had previously described stand-alone odor and chemesthetic threshold values, also holds promise to describe, and eventually predict, olfactory and chemesthetic detectability functions, albeit functions from additional compounds are needed to strengthen the QSAR.
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Poluentes Atmosféricos/análise , Poluentes Atmosféricos/química , Córnea/inervação , Cavidade Nasal/inervação , Odorantes/análise , Mucosa Olfatória/fisiologia , Olfato/fisiologia , Nervo Trigêmeo/fisiologia , Relação Dose-Resposta a Droga , Humanos , Relação Quantitativa Estrutura-Atividade , Limiar SensorialRESUMO
BACKGROUND: The high homology and opposite orientation of RH genes promote rearrangements between them and generate a large number of RHD and RHCE variants which can be inherited together. Searching of RHD-CE genotypes predicting partial antigens in donors is of interest in order to find more closely matched donors for African descent patients. This study aimed to evaluate a molecular approach to search for RhCE variants in a cohort of individuals with altered expression of D antigen and determine the association of RH variant alleles in Brazilian blood donors. METHODS: From 80,961 blood samples tested, 421 with atypical D typing results were studied. The samples were phenotyped for C, c, E, e antigens. Rh variants were identified using molecular techniques. RESULTS: All 421 samples had altered RHD alleles, being 56·3% of them partial D. Among them, 94·9% presented variant RHCE*ce and the most common associations were: RHD*weak D type 4.2.2 with RHCE*ceAR; RHD*DAR linked to RHCE*ceVS.02; RHD*weak D type 4.0 linked to RHCE*ceVS.02 and RHCE*ce (c.48C, c.105T, c.733G, c.744C, c.1025T). Among the samples with RhCE variants, 10·6% predict partial c, partial e, hr(B) - and/or hr(S) - and 100% express low prevalence antigens. CONCLUSION: Targeting individuals with altered expression of D antigen can be a good strategy for finding donors with RhCE variants. In our study 94·9% of the partial D samples revealed altered RHCE variant alleles and 5·7% of the samples with altered RHD allele predicted partial c, partial e and the lack of the high prevalence hr(B) and hr(S) antigens.
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Alelos , Doadores de Sangue , Variação Genética , Genótipo , Sistema do Grupo Sanguíneo Rh-Hr , Brasil , Feminino , Técnicas de Genotipagem , Humanos , Masculino , Sistema do Grupo Sanguíneo Rh-Hr/sangue , Sistema do Grupo Sanguíneo Rh-Hr/genéticaRESUMO
We report observations of superradiance for atoms trapped in the near field of a photonic crystal waveguide (PCW). By fabricating the PCW with a band edge near the D(1) transition of atomic cesium, strong interaction is achieved between trapped atoms and guided-mode photons. Following short-pulse excitation, we record the decay of guided-mode emission and find a superradiant emission rate scaling as ΓÌ (SR)âNÌ Γ(1D) for average atom number 0.19â²NÌ â²2.6 atoms, where Γ(1D)/Γ'=1.0±0.1 is the peak single-atom radiative decay rate into the PCW guided mode, and Γ' is the radiative decay rate into all the other channels. These advances provide new tools for investigations of photon-mediated atom-atom interactions in the many-body regime.
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BACKGROUND: A number of changes in the management of heart transplantation (HT) patients have each tended to reduce the risk of post-HT hematologic cancer, but little information is available concerning the overall effect on incidence in the HT population. METHODS: Comparison of data from the Spanish Post-Heart-Transplantation Tumour Registry for the periods 1991-2000 and 2001-2010. RESULTS: The incidence among patients who underwent HT in the latter period was about half that observed in the former, with a particularly marked improvement in regard to incidence more than five yr post-HT. CONCLUSIONS: Changes in HT patient management have jointly reduced the risk of hematologic cancer in the Spanish HT population. Long-term risk appears to have benefited more than short-term risk.
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Transplante de Coração/estatística & dados numéricos , Neoplasias Hematológicas/epidemiologia , Idoso , Feminino , Seguimentos , Insuficiência Cardíaca/cirurgia , Neoplasias Hematológicas/prevenção & controle , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Sistema de Registros , Fatores de Risco , Espanha/epidemiologiaRESUMO
BACKGROUND: The effect of pregnancy on skeletal muscle still has not been clearly established. The aim of the present study was to investigate the effect of pregnancy on muscle weight and contractile properties of soleus and plantaris muscles. METHODS: The female Sprague-Dawley rats were divided into two groups: nonpregnant (NP, 250 ± 4 g, n = 8) and late-pregnant (LP, 305 ± 13 g, n = 8). The right plantaris and soleus muscles were liberated from the surrounding tissues. Each muscle was placed on setup to mechanical recording with electric stimulation. In the optimum length of each muscle were recorded single twitches, tetani and fatigue. RESULTS: The weight and cross-sectional area of soleus and plantaris muscles from pregnant rats was increased respect to nonpregnant rats. The maximal twitch tension decreased in both muscles during pregnancy respect to nonpregnant group. The soleus muscle of LP group developed lesser tetanic tension than NP group. However, the plantaris muscle showed a different behavior: to lower frequencies (5-30 Hz) the NP group developed greater tetanic tension than LP group, and for higher frequencies (40-100 Hz), the LP group developed greater tetanic tension than NP group. Finally, the soleus muscle was more resistance to fatigue than plantaris muscle in pregnant rats. CONCLUSION: The fast and slow skeletal muscles show a differential contractile response during pregnancy, in tetanic tension and fatigue (Fig. 4, Ref. 48).
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Contração Muscular/fisiologia , Fadiga Muscular/fisiologia , Músculo Esquelético/fisiologia , Gravidez/fisiologia , Potenciais de Ação , Animais , Feminino , Humanos , Modelos Animais , Músculo Esquelético/anatomia & histologia , Tamanho do Órgão , Ratos , Ratos Sprague-Dawley , Valores de ReferênciaRESUMO
Vascular endothelial growth factor (VEGF) is a cytokine involved in angiogenesis and is closely related to the nitric oxide-cyclic guanosine monophosphate pathway, a target for sildenafil. We investigated for the first time whether three clinically relevant polymorphisms in the VEGF gene are associated with altered responsiveness to sildenafil treatment in postoperative erectile dysfunction (PED) and clinical erectile dysfunction (CED). We determined VEGF genotypes for three polymorphisms in VEGF promoter: -2578C>A (rs699947), -1154G>A (rs1570360) and -634G>C (rs2010963) in 126 patients with erectile dysfunction (ED; 66 patients with PED and 60 patients with CED). The patients were classified as good or poor responders to sildenafil (GR and PR groups, respectively) according to their responses with basis on the changes in five-item version of the International Index for Erectile Function (5-IIEF). We found an association of the -1154AA genotype with PR in both PED and CED patients (P<0.05), whereas the -2578AA and the -2578CA genotypes were associated with PR only in the CED group (P<0.05). The AAG haplotype was more common in PR than in GR patients (38% versus 20%, respectively; P=0.032) in the CED group, thus increasing the risk for a worse response to sildenafil (odds ratio, OR=2.33, 95% confidence interval, CI=1.07-5.09). However, this finding does not resist to Bonferroni's correction (P>0.0125). Our results indicate that VEGF polymorphisms affect the responsiveness of PED and CED patients to sildenafil. These findings may help to improve the therapy of patients with ED.
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Disfunção Erétil/tratamento farmacológico , Disfunção Erétil/genética , Piperazinas/uso terapêutico , Sulfonas/uso terapêutico , Agentes Urológicos/uso terapêutico , Fator A de Crescimento do Endotélio Vascular/genética , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Regiões Promotoras Genéticas , Purinas/uso terapêutico , Citrato de SildenafilaRESUMO
Erectile dysfunction (ED) is usually treated with sildenafil. Although genetic polymorphisms in the endothelial nitric oxide synthase (eNOS) gene may impair endogenous NO formation, there is little information about how eNOS polymorphisms and haplotypes affect the responses to sildenafil. We studied 118 patients; 63 patients had ED secondary to radical prostatectomy (PED) and 55 had organic, clinical ED. eNOS genotypes for three eNOS polymorphisms (T(-786)C, rs2070744; a variable number of tandem repeats (VNTR) in intron 4; and Glu298Asp, rs1799983) were determined, and eNOS haplotypes were estimated using PHASE 2.1. The clinical responses to sildenafil were evaluated and the patients were classified as good responders (GR) or poor responders (PR) when their changes in five-item version of International Index for Erectile Function questionnaire were above or below the median value. The TC/CC genotypes and the C allele for the T(-786)C polymorphism were more common in GR, compared with PR patients with PED. However, the 4b4a/4a4a genotypes and the 4a allele for the VNTR polymorphism in intron 4 were more common in GR, compared with PR patients with clinical ED. The C-4a-Glu haplotype was more common in GR than in PR patients with PED. Conversely, the T-4b-Asp haplotype was less common in GR than in PR patients with PED. No other significant differences were found. Our findings show evidence that eNOS polymorphisms affect the responses of PED and clinical ED patients to sildenafil.
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Disfunção Erétil/tratamento farmacológico , Disfunção Erétil/genética , Óxido Nítrico Sintase Tipo III/genética , Piperazinas/administração & dosagem , Sulfonas/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Farmacológicos , Disfunção Erétil/patologia , Genótipo , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Repetições Minissatélites , Piperazinas/efeitos adversos , Polimorfismo de Nucleotídeo Único , Prostatectomia , Purinas/administração & dosagem , Purinas/efeitos adversos , Citrato de Sildenafila , Sulfonas/efeitos adversos , Inquéritos e QuestionáriosRESUMO
The aim of this study was to develop an objective method to determine the incidence of pleiomorphisms and its influence on the distribution of sperm morphometric subpopulations in ejaculates of howling monkeys (Alouatta caraya) by using a combination of computerized analysis system (ASMA) and principal component analysis (PCA) methods. Ejaculates were collected by electroejaculation methods on a regular basis from five individuals maintained under identical captive environmental, nutritional, and management conditions. Each sperm head was measured for dimensional parameters (Area [A, (square micrometers)], Perimeter [P, (micrometers)], Length [L, (micrometers)], and Width [W, (micrometers)]) and shape-derived parameters (Ellipticity [(L/W)], Elongation [(L - W)/(L + W)], and Rugosity [(4лA/P (2))]). PCA revealed two principal components explaining more than the 96 % of the variance. Clustering methods and discriminant analyzes were performed and seven separate subpopulations were identified. There were differences (P < 0.001) in the distribution of the seven subpopulations as well as in the incidence of abnormal pleiomorphisms (58.6 %, 49.8 %, 35.1 %, 66.4 %, and 55.1 %, P < 0.05) among the five donors tested. Our results indicated that differences among individuals related to the incidence of pleiomorphisms, and sperm subpopulational structure was not related to the captivity conditions or the sperm collection method, since all individuals were studied under identical conditions. In conclusion, the combination of ASMA and PCA is a useful clinical diagnostic resource for detecting deficiencies in sperm morphology and sperm subpopulations in A. caraya ejaculates that could be used in ex situ conservation programs of threatened species in Alouatta genus or even other endangered neotropical primate species.
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Alouatta/anatomia & histologia , Animais de Zoológico/anatomia & histologia , Espermatozoides/citologia , Bem-Estar do Animal , Animais , Processamento de Imagem Assistida por Computador , Incidência , Masculino , Espermatozoides/classificaçãoRESUMO
AIM: To evaluate the effect of an educational intervention among primary care physicians on several indicators of good clinical practice in diabetes care. METHODS: Two groups of physicians were randomly assigned to the intervention or control group (IG and CG). Every physician randomly selected two samples of patients from all type 2 diabetic patients aged 40 years and above and diagnosed more than a year ago. Baseline and final information were collected cross-sectionally 12 months apart, in two independent samples of 30 patients per physician. The educational intervention comprised: distribution of educational materials and physicians' specific bench-marking information, an on-line course and three on-site educational workshops on diabetes. External observers collected information directly from the physicians and from the medical records of the patients on personal and family history of disease and on the evolution and treatment of their disease. Baseline information was collected retrospectively in the control group. RESULTS: Intervention group comprised 53 physicians who included a total of 3018 patients in the baseline and final evaluations. CG comprised 50 physicians who included 2868 patients in the same evaluations. Measurement of micro-albuminuria in the last 12 months (OR = 1.6, 95% CI: 1.1-2.4) and foot examination in the last year (OR = 2.0, 95% CI: 1.1-3.6) were the indicators for which greater improvement was found in the IG. No other indicator considered showed statistically significant improvement between groups. CONCLUSIONS: The identification of indicators with very low level of compliance and the implementation of a simple intervention in physicians to correct them is effective in improving the quality of care of diabetic patients.
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Competência Clínica/normas , Diabetes Mellitus Tipo 2/terapia , Educação de Pós-Graduação em Medicina/métodos , Médicos de Atenção Primária/educação , Adulto , Idoso , Estudos Transversais , Feminino , Fidelidade a Diretrizes , Humanos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Atenção Primária à Saúde/normas , Qualidade da Assistência à Saúde , EspanhaRESUMO
We report a measurement of the proton-air cross section for particle production at the center-of-mass energy per nucleon of 57 TeV. This is derived from the distribution of the depths of shower maxima observed with the Pierre Auger Observatory: systematic uncertainties are studied in detail. Analyzing the tail of the distribution of the shower maxima, a proton-air cross section of [505±22(stat)(-36)(+28)(syst)] mb is found.