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1.
Faraday Discuss ; 227: 306-320, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33305778

RESUMEN

Herein we demonstrate that adding single atoms of selected transition metals to graphitic carbon nitrides allows the tailoring of the electronic and chemical properties of these 2D nanomaterials, directly impacting their usage in photocatalysis. These single-atom photocatalysts were successfully prepared with Ni2+, Pt2+ or Ru3+ by cation exchange, using poly(heptazine imides) (PHI) as the 2D layered platform. Differences in photocatalytic performance for these metals were assessed using rhodamine-B (RhB) and methyl orange (MO) as model compounds for degradation. We have demonstrated that single atoms may either improve or impair the degradation of RhB and MO, depending on the proper matching of the net charge of these molecules and the surface potential of the catalyst, which in turn is responsive to the metal incorporated into the PHI nanostructures. Computer simulations demonstrated that even one transition metal cation caused dramatic changes in the electronic structure of PHI, especially regarding light absorption, which was extended all along the visible up to the near IR region. Besides introducing new quantum states, the metal atoms strongly polarized the molecular orbitals across the PHI and electrostatic fields arising from the electronic transitions became at least tenfold stronger. This simple proof of concept demonstrates that these new materials hold promise as tools for many important photocatalytic reactions that are strongly dependent on our ability to control surface charge and its polarization under illumination, such as H2 evolution, CO2 reduction and photooxidation in general.

2.
J Clin Ultrasound ; 45(5): 252-260, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28374885

RESUMEN

OBJECTIVE: To evaluate the differences in sonographic (US) distance and volume measurements from different sonologists and identify the optimal parameters to avoid clinically relevant variations in the measurement of BI-RADS 3 breast masses. METHODS: For this cross-sectional study with prospectively collected data, four physicians with various levels of experience in US, herein called sonologists, performed distance and volume US measurements of 80 masses classified as BI-RADS 3. The Cochran Q test was used to compare the matched sets of rates of clinically relevant variability between all pairs of sonologists' measurements. RESULTS: There were clinically relevant differences between sonologists in the measurements of the longest diameter (range, 17.5-43.7%, p = 0.003), the longest diameter perpendicular to the previous one (anteroposterior diameter) (17.5-33.7%, p = 0.06), the third diameter orthogonal to the plane defined by the previous two (transverse diameter) (28.7-55%, p = 0.001), and at least two of those three diameters (18.7-38.7%, p = 0.015). The smallest clinically relevant differences were observed with volume measurements (range of differences, 6.2-13.7%, p = 0.51). CONCLUSIONS: Volume measurement technique was associated with the least variations, whereas distance measurements, which are used routinely, were associated with unacceptable rates of clinically relevant variations. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 45:252-260, 2017.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Sistemas de Información Radiológica/estadística & datos numéricos , Ultrasonografía Mamaria/métodos , Adulto , Mama/diagnóstico por imagen , Estudios Transversales , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Persona de Mediana Edad , Estudios Prospectivos , Adulto Joven
3.
Artículo en Inglés | MEDLINE | ID: mdl-33919220

RESUMEN

OBJECTIVE: To examine the association between phase angle (PhA) and bioelectrical impedance vector analysis (BIVA) and components of physical performance in male youth soccer players. DESIGN: Cross-sectional. METHODS: Sixty-two players from two professional soccer academies were recruited. Electrical bioimpedance was used to obtain the PhA and BIVA. Body fat (BF) and lean soft tissue mass (LSTM) were measured by dual-energy X-ray absorptiometry. All players completed physical tests including the standing long jump (SLJ), Carminatti's test (peak speed at the end of the test, PST-CAR), 10 m and 30 m straight-line sprints, and repeated-sprint ability (RSA) test (RSAbest and RSAmean times). RESULTS: Adjusting for chronological age, BF, and LSTM, multiple regression analysis outputs showed that PhA remained inversely related to RSAmean (ß = -0.362; p < 0.001), RSAbest (ß = -0.239; p = 0.020), 10 m (ß = -0.379; p = 0.012), and 30 m (ß = -0.438; p < 0.001) sprint times, while the association with PST-CAR and SLJ performance were statistically non-significant. In addition, BIVA showed that differences in confidence ellipses were found between athletes in the reference population and the study sample (p < 0.05). The tolerance ellipses indicated that the athletes in the present study had more total body water (TCW) and lower proportions of intracellular water (ICW) to extracellular water (ECW). The reference population had more TCW and ICW/ECW. CONCLUSIONS: Our results suggest that young soccer players with higher PhA values, indicating better cell integrity and functionality, have better performance in typical anaerobic running activities, such as sprinting speed and RSA performance, adjusted to age and body composition characteristics.


Asunto(s)
Rendimiento Atlético , Carrera , Fútbol , Adolescente , Estudios Transversales , Prueba de Esfuerzo , Humanos , Masculino
4.
Rev Bras Ginecol Obstet ; 38(4): 170-6, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27093646

RESUMEN

Objective The objective of this study is to assess whether the largest cyst diameter is useful for BI-RADS ultrasonography classification of predominantly solid breast masses with an oval shape, circumscribed margins, and largest axis parallel to the skin, which, except for the cystic component, would be likely classified as benign. Methods This study received approval from the local institutional review board. From March 2009 to August 2014, we prospectively biopsied 170 breast masses from 164 women. We grouped the largest cyst and mass diameters according to histopathological diagnoses. We used Student's t-test, linear regression, and the area under the receiver operating characteristic curve (AUC) for statistical assessment. Results Histopathological examination revealed 143 (84%) benign and 27 (16%) malignant masses. The mean largest mass diameter was larger among malignant (mean ± standard deviation, 34.1 ± 16.6 mm) than benign masses (24.7 ± 16.7 mm) (P < 0.008). The mean largest cyst diameter was also larger among malignant (9.9 ± 7.1 mm) than benign masses (4.6 ± 3.6 mm) (P < 0.001). Agreement between measurements of the largest mass and cyst diameters was low (R(2) = 0.26). AUC for the largest cyst diameter (0.78) was similar to the AUC for the largest mass diameter (0.69) (p = 0.2). A largest cyst diameter < 3, ≥ 3 to < 11, and ≥ 11 mm had a positive predictive value of 0, 15, and 52%, respectively. Conclusion A largest cystic component < 3 mm identified within breast masses that show favorable characteristics may be considered clinically inconsequential in ultrasonography characterization. Conversely, masses with a largest cystic component ≥ 3 mm should be classified as BI-RADS-US category 4.


Asunto(s)
Quiste Mamario/diagnóstico por imagen , Quiste Mamario/patología , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Ultrasonografía Mamaria , Adulto , Anciano , Estudios Transversales , Diagnóstico Diferencial , Femenino , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Medición de Riesgo
5.
Cad Saude Publica ; 29(8): 1565-71, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24005922

RESUMEN

This study aims to assess the effects air pollution on hospitalization due to hypertension. An ecological study was conducted using data regarding hospitalizations due to hypertension in São José dos Campos, State of São Paulo, Brazil between January 1, 2007 and December 31, 2010. The pollutants analyzed by this study were particulate matter, sulfur dioxide and ozone. A significant association between exposure to particulate matter and hospitalization due to hypertension was identified using Poisson regression with lags of up to four days. Relative risk of hospital admission ranged between 1,009 and 1,019. A 10µg/m³ increase in concentration of particulate matter was associated with a 13% increase in risk of hospitalization.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Exposición a Riesgos Ambientales/efectos adversos , Hipertensión/etiología , Ozono/toxicidad , Material Particulado/toxicidad , Dióxido de Azufre/toxicidad , Contaminantes Atmosféricos/análisis , Brasil/epidemiología , Exposición a Riesgos Ambientales/análisis , Hospitalización/estadística & datos numéricos , Humanos , Hipertensión/epidemiología , Ozono/análisis , Material Particulado/análisis , Dióxido de Azufre/análisis
6.
Cad Saude Publica ; 28(7): 1319-24, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22729262

RESUMEN

Some effects of environmental pollution on human health are known, especially those affecting the respiratory and cardiovascular systems. The current study aimed to estimate these effects on the production of hospital admissions for stroke. This was an ecological study using hospital admissions data in São José dos Campos, São Paulo State, Brazil, with diagnosis of stroke, from January 1, 2007, to April 30, 2008. The target pollutants were particulate matter, sulfur dioxide, and ozone. Use of a Poisson linear regression model showed that same-day exposure to particulate matter was associated with hospitalization for stroke (RR = 1.013; 95%CI: 1.001-1.025). An increase of 10 µg/m(3) in this pollutant increased the risk of hospitalization by 12% (RR = 1.137; 95%CI: 1.014-1.276). In the multi-pollutant model, it was thus possible to identify particulate matter as associated with hospitalization for stroke in a medium-sized city like São José dos Campos.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Contaminación del Aire/efectos adversos , Exposición a Riesgos Ambientales/efectos adversos , Hospitalización/estadística & datos numéricos , Accidente Cerebrovascular/etiología , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Brasil , Femenino , Humanos , Exposición por Inhalación/efectos adversos , Masculino , Persona de Mediana Edad , Ozono/efectos adversos , Ozono/análisis , Material Particulado/efectos adversos , Accidente Cerebrovascular/diagnóstico , Dióxido de Azufre/efectos adversos , Dióxido de Azufre/análisis
7.
Rev. bras. ginecol. obstet ; 38(4): 170-176, Apr. 2016. tab, graf
Artículo en Inglés | LILACS | ID: lil-783886

RESUMEN

Abstract Objective The objective of this study is to assess whether the largest cyst diameter is useful for BI-RADS ultrasonography classification of predominantly solid breast masses with an oval shape, circumscribed margins, and largest axis parallel to the skin, which, except for the cystic component, would be likely classified as benign. Methods This study received approval from the local institutional review board. From March 2009 to August 2014, we prospectively biopsied 170 breast masses from 164 women. We grouped the largest cyst and mass diameters according to histopathological diagnoses. We used Student's t-test, linear regression, and the area under the receiver operating characteristic curve (AUC) for statistical assessment. Results Histopathological examination revealed 143 (84%) benign and 27 (16%) malignant masses. The mean largest mass diameter was larger among malignant (mean standard deviation, 34.1 16.6 mm) than benign masses (24.7 16.7 mm) (P < 0.008). The mean largest cyst diameter was also larger among malignant (9.9 7.1 mm) than benign masses (4.6 3.6 mm) (P < 0.001). Agreement between measurements of the largest mass and cyst diameters was low (R2 = 0.26). AUC for the largest cyst diameter (0.78) was similar to the AUC for the largest mass diameter (0.69) ( p = 0.2). A largest cyst diameter < 3, 3 to < 11, and 11 mm had a positive predictive value of 0, 15, and 52%, respectively. Conclusion A largest cystic component < 3 mm identified within breast masses that show favorable characteristics may be considered clinically inconsequential in ultrasonography characterization. Conversely, masses with a largest cystic component 3 mm should be classified as BI-RADS-US category 4.


Resumo Objetivo Avaliar se o maior diâmetro do cisto é útil para a classificação ultrassonográfica BI-RADS de nódulos mamários predominantemente sólidos, com forma oval, margens circunscritas e maior eixo paralelo à pele que, exceto pela presença do componente cístico, seriam classificados como provavelmente benignos. Métodos Este estudo foi aprovado pelo Comitê de Ética local. De março de 2009 a agosto de 2014, 170 nódulos mamários de 164 mulheres foram prospectivamente biópsiados. As medidas do maior diâmetro do maior cisto e do maior diâmetro do nódulo foram agrupados de acordo com os diagnósticos histopatológicos. O teste t de Student, a regressão linear e a área sob a curva ROC (AUC) foram utilizados para a avaliação estatística. Resultados O exame histopatológico revelou 143 (84%) nódulos benignos e 27 (16%) nódulos malignos. A média da medida do maior diâmetro dos nódulos foi maior entre os nódulos malignos (média desvio padrão, 34,1 16,6 mm) do que nos nódulos benignos (24,7 16,7 mm) (p < 0,008). A média do maior diâmetro do maior cisto também foi maior entre os nódulos malignos (9,9 7,1 mm) do que nos nódulos benignos (4,6 3,6 mm) (p < 0,001). A concordância entre as medidas dos maiores diâmetros dos nódulos e do maior diâmetro do maior cisto foi baixa (R2 = 0,26). A AUC do maior diâmetro do maior cisto (0,78) foi semelhante à AUC do maior diâmetro do nódulo (0,69) (p = 0,2). Os maiores diâmetros dos maiores cistos medindo < 3; 3 e < 11; e 11 mm tiveram um valor preditivo positivo de 0, 15 e 52%, respectivamente. Conclusão Componentes císticos < 3 mm identificados dentro de nódulos mamários que apresentam as demais características provavelmente benignas podem ser considerados clinicamente irrelevantes na caracterização ultrassonográfica. Por outro lado, nódulos que apresentam um componente cístico medindo 3 mm devem ser classificadas na categoria BI-RADS-US 4.


Asunto(s)
Humanos , Femenino , Adulto , Persona de Mediana Edad , Anciano , Quiste Mamario/diagnóstico por imagen , Quiste Mamario/patología , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Ultrasonografía Mamaria , Estudios Transversales , Diagnóstico Diferencial , Estudios Prospectivos , Medición de Riesgo
8.
Cad. saúde pública ; 29(8): 1565-1571, Ago. 2013. ilus, tab
Artículo en Inglés | LILACS | ID: lil-684643

RESUMEN

This study aims to assess the effects air pollution on hospitalization due to hypertension. An ecological study was conducted using data regarding hospitalizations due to hypertension in São José dos Campos, State of São Paulo, Brazil between January 1, 2007 and December 31, 2010. The pollutants analyzed by this study were particulate matter, sulfur dioxide and ozone. A significant association between exposure to particulate matter and hospitalization due to hypertension was identified using Poisson regression with lags of up to four days. Relative risk of hospital admission ranged between 1,009 and 1,019. A 10μg/m³ increase in concentration of particulate matter was associated with a 13% increase in risk of hospitalization.


Alguns dos efeitos da poluição ambiental na saúde humana são conhecidos, destacando aqueles no sistema cardiovascular. Este trabalho tem por objetivo estimar esses efeitos nas internações por hipertensão arterial. Foi um estudo ecológico realizado com dados de internações da cidade de São José dos Campos, São Paulo, Brasil, relativos aos diagnósticos de hipertensão arterial, entre 1o de janeiro de 2007 e 31 de dezembro de 2010. Os poluentes estudados foram material particulado, dióxido de enxofre e ozônio. Utilizando-se de modelo linear generalizado da regressão de Poisson e defasagens de até quatro dias, foi possível identificar associação significativa entre a exposição ao material particulado e a internação por hipertensão, com os riscos variando entre 1.009 e 1.019; aumento de 10μg/m³ desse poluente aumenta o risco de internação em até 13%. Assim, foi possível identificar o material particulado, no modelo multipoluente, como associado à internação por hipertensão arterial numa cidade de porte médio, como São José dos Campos.


Algunos de los efectos de la contaminación ambiental en la salud humana son conocidos, destacando aquellos en nuestro sistema cardiovascular. Este trabajo tiene por objetivo estimar esos efectos en los internamientos por hipertensión arterial. Se trató de un estudio ecológico, realizado con datos de internamientos de la ciudad de São José dos Campos, São Paulo, Brasil, relativos a los diagnósticos de hipertensión arterial, entre el 1o de enero de 2007 y el 31 de diciembre de 2010. Los contaminantes estudiados fueron material particulado, dióxido de azufre y ozono. Se utilizó un modelo lineal generalizado de regresión de Poisson y desfases de hasta cuatro días; fue posible identificar una asociación significativa entre la exposición al material particulado y el internamiento por hipertensión con los riesgos, variando entre 1.009 y 1.019; el aumento de 10µg/m3 de ese contaminante aumenta el riesgo de internamiento en hasta un 13%. Así, fue posible identificar el material particulado, en el modelo multicontaminante, como asociado al internamiento por hipertensión arterial en una ciudad de porte medio, como São José dos Campos.


Asunto(s)
Humanos , Contaminantes Atmosféricos/toxicidad , Exposición a Riesgos Ambientales/efectos adversos , Hipertensión/etiología , Ozono/toxicidad , Material Particulado/toxicidad , Dióxido de Azufre/toxicidad , Contaminantes Atmosféricos/análisis , Brasil/epidemiología , Exposición a Riesgos Ambientales/análisis , Hospitalización/estadística & datos numéricos , Hipertensión/epidemiología , Ozono/análisis , Material Particulado/análisis , Dióxido de Azufre/análisis
9.
Cad. saúde pública ; 28(7): 1319-1324, jul. 2012.
Artículo en Inglés | LILACS | ID: lil-638726

RESUMEN

Some effects of environmental pollution on human health are known, especially those affecting the respiratory and cardiovascular systems. The current study aimed to estimate these effects on the production of hospital admissions for stroke. This was an ecological study using hospital admissions data in São José dos Campos, São Paulo State, Brazil, with diagnosis of stroke, from January 1, 2007, to April 30, 2008. The target pollutants were particulate matter, sulfur dioxide, and ozone. Use of a Poisson linear regression model showed that same-day exposure to particulate matter was associated with hospitalization for stroke (RR = 1.013; 95%CI: 1.001-1.025). An increase of 10µg/m³ in this pollutant increased the risk of hospitalization by 12% (RR = 1.137; 95%CI: 1.014-1.276). In the multi-pollutant model, it was thus possible to identify particulate matter as associated with hospitalization for stroke in a medium-sized city like São José dos Campos.


Alguns dos efeitos da poluição ambiental na saúde humana são conhecidos, destacando aqueles nos sistemas respiratório e cardiovascular. Este trabalho tem por objetivo estimar esses efeitos na gênese das internações por acidente vasculoencefálico. Foi um estudo ecológico realizado com dados de internações da cidade de São José dos Campos, São Paulo, Brasil, relativos aos diagnósticos de acidente vascular cerebral, entre 1º de janeiro de 2007 e 30 de abril de 2008. Os poluentes estudados foram material particulado, dióxido de enxofre e ozônio. Utilizando-se de modelo linear generalizado da regressão de Poisson, foi possível identificar exposição ao material particulado, no mesmo dia, como associado à internação por acidente vasculoencefálico (RR = 1,013; IC95%: 1,001-1,025). O aumento de 10µg/m3 desse poluente aumenta o risco de internação em 12% (RR = 1,137; IC95%: 1,014-1,276). Assim, foi possível identificar o material particulado, no modelo multipoluente, como associado à internação por acidente vasculoencefálico numa cidade de porte médio, como São José dos Campos.


Asunto(s)
Femenino , Humanos , Masculino , Persona de Mediana Edad , Contaminantes Atmosféricos/efectos adversos , Contaminación del Aire/efectos adversos , Exposición a Riesgos Ambientales/efectos adversos , Hospitalización/estadística & datos numéricos , Accidente Cerebrovascular/etiología , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Brasil , Exposición por Inhalación/efectos adversos , Ozono/efectos adversos , Ozono/análisis , Material Particulado/efectos adversos , Accidente Cerebrovascular/diagnóstico , Dióxido de Azufre/efectos adversos , Dióxido de Azufre/análisis
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