ABSTRACT Introduction: According to the American Heart Association guideline for coronary artery bypass grafting (CABG), female patients undergoing on-pump CABG (ONCAB) are at higher risk of short-term adverse outcomes than male patients. However, whether off-pump CABG (OPCAB) can improve the short-term outcome of female patients compared to ONCAB remains unclear. Methods: We conducted a meta-analysis to study the effect of the female sex on short-term outcomes of OPCAB vs. ONCAB. A total of 31,115 patients were enrolled in 12 studies, including 20,245 females who underwent ONCAB and 10,910 females who underwent OPCAB. Results: The in-hospital mortality in female patients who underwent OPCAB was significantly lower than in those in the ONCAB group with (2.7% vs. 3.4%; odds ratio [OR] 0.76; 95% confidence interval [CI] 0.65-0.89) and without (OR 0.68; 95% CI 0.52-0.89) adjustment for cardiovascular risk factor. The incidence of postoperative stroke in female patients who underwent OPCAB was lower than in those in the ONCAB group (1.2% vs. 2.1%; OR 0.59; 95% CI 0.48-0.73) before cardiovascular risk factor adjustment but was not significant (OR 0.87; 95% CI 0,66-1.16) after adjustment. There was no significant difference in the incidence of postoperative myocardial infarction between women who underwent OPCAB and those in the ONCAB group (1.3% vs. 2.3%; OR 0.88; 95% CI 0.54-1.43). Conclusion: In contrast to the American Heart Association CABG guideline, female patients who had OPCAB don’t have unfavorable outcomes compared with the ONCAB group.

ABSTRACT The selection of key additive materials for a new type of oil-based drilling fluid was studied in this paper. The oil-based drilling fluid can strengthen well walls and ensure safety. It is suitable for high-temperature and high-pressure wells, deep wells and ultra-deep wells. A new type of high-temperature white oil-based drilling fluid was prepared by using 5# white oil as continuous phase, HIS as thickening agent, SDBS as emulsifier, and asphalt powder oxidized at 180°C as filtration agent. The results showed that the saturation concentration of sodium dodecyl benzene sulfonate (SDBS) was 4%, the saturation concentration of asphalt powder oxidized at 180°C was 4%, the saturation concentration of Tween-80 was 10%. The final resistance of high temperature and high pressure oil based drilling fluid formulation material is: No. 5 white oil + 4% SDBS + 5% modified bentonite + 4% asphalt powder oxidized at 180°C + 10% Tween-80 + 1.5% Barite + CaO. The performance evaluation of the new oil-based drilling fluid shows that shale expansion is 0.21mm, anti-temperature up to 220°C, and anti-pollution ability is good. The rheological properties, resistance of high-temperature high- pressure have been greatly improved. Therefore, the new white oil-based drilling fluid can resistance of high- temperature and also has low toxicity, which can meet the exploration and development of more complex wells.

ABSTRACT Bentonite is the most important material used in oil and gas field drilling operations. However, the properties of natural bentonite cannot meet the requirements of bentonite for drilling. Therefore, researchers pay much attention to the modification of bentonite. The hydroxyethyl cellulose-acrylamide graft polymer was synthesized by microwave assisted, and the bentonite composite based on the graft polymer was prepared. FTIR, XRD and SEM results show that the polymer exists between the layers and the surface of the bentonite. Research on the bentonite composite showed that the yield point and filtration properties of bentonite composite are higher than natural bentonite at 90 to 150 celsius. The composite yield point / plastic viscosity ratio is more than 0.6 and the minimum fluid loss is only 9.3ml, which can meet the requirements of drilling-grade bentonite. This material has the potential to be a candidate for drilling applications.

OBJECTIVE: To examine and describe coronary heart disease (CHD) mortality and its pattern of change (trend) by sex, age, and area of residence (urban versus rural) in Tianjin, China, within the context of epidemiological transition, and compare it with current trends in the Americas and Europe. METHODS: A total of 104 393 cases of CHD death in Tianjin occurring between 1999 and 2008 were monitored. Death due to CHD was coded using International Classification of Diseases (ICD) standards (ninth and tenth revisions). Standardized CHD mortality rates and their trends were analyzed by age, sex, and urban versus rural residence. RESULTS: During the 10-year study period, the proportion of total deaths due to CHD in Tianjin increased significantly (from 16% to 24%) and age-standardized CHD mortality increased slightly (with no statistical differences), in contrast to CHD mortality trends in various countries in the Americas and Europe, which are declining. No difference was found in Tianjin's CHD mortality trend by sex. Overall CHD mortality was consistently higher among older age groups, males, and residents of urban areas. The proportion of CHD deaths occurring outside hospitals was 55.81%, with a declining trend over the study period. Rural areas had a higher proportion of outside-hospital CHD mortality than urban areas, but no difference was found across age groups. CONCLUSIONS: From 1999 to 2008, CHD mortality in Tianjin varied by sex, age, and urban versus rural area of residence. Future research to identify CHD risk factors and the populations most vulnerable to the disease is recommended to help strengthen CHD prevention. Strategies for CHD control similar to those used in various developed countries in the Americas and Europe should be developed to reduce the CHD burden in China.

OBJETIVO: Examinar y describir la mortalidad por cardiopatía coronaria y su patrón de cambio (tendencia) por sexo, edad y zona de residencia (urbana frente a rural) en Tianjín, China, en el contexto de la transición epidemiológica, y compararla con las tendencias actuales en las Américas y Europa. MÉTODOS: Se analizaron 104 393 casos de muertes debidas a cardiopatía coronaria ocurridas en Tianjín entre 1999 y 2008. Se codificó la mortalidad debida a cardiopatía coronaria según la Clasificación Internacional de Enfermedades (novena y décima revisiones). Se analizaron las tasas estandarizadas de mortalidad por cardiopatía coronaria y sus tendencias por edad, sexo y residencia urbana frente a rural. RESULTADOS: Durante el período de estudio, de 10 años, la proporción de la mortalidad total debida a cardiopatía coronaria registrada en Tianjín aumentó significativamente (de 16% a 24%) y la mortalidad por cardiopatía coronaria estandarizada por edad aumentó levemente (sin significación estadística), en contraposición con las tendencias de mortalidad por cardiopatía coronaria observadas en diversos países de las Américas y Europa, que están descendiendo. No se encontraron diferencias en la tendencia de la mortalidad por cardiopatía coronaria por sexo en Tianjín. La mortalidad general por cardiopatía coronaria fue sistemáticamente más elevada en los grupos de mayor edad, los varones y los residentes de zonas urbanas. La proporción de muertes debidas a cardiopatía coronaria que ocurrieron fuera de los hospitales fue de 55,81%, con una tendencia decreciente en el período de estudio. Esta proporción fue mayor en las zonas rurales que en las urbanas, pero no se encontró diferencia entre los distintos grupos de edad. CONCLUSIONES: Desde 1999 hasta el 2008, la mortalidad por cardiopatía coronaria en Tianjín varió según el sexo, la edad y la residencia urbana frente a la rural. Se recomienda efectuar nuevas investigaciones para identificar los factores de riesgo de cardiopatía coronaria y las poblaciones más vulnerables a la enfermedad, a fin de mejorar la prevención de la cardiopatía coronaria. Deben elaborarse estrategias para controlar la enfermedad similares a las usadas en varios países desarrollados de las Américas y Europa para reducir la carga de cardiopatía coronaria en China.

El uso de la lengua materna es una ocurrencia común en los contextos de la enseñanza de la lengua extranjera, a pesar de que a veces reciba críticas por su interferencia en la adquisición de la Lengua meta. Mientras que los docentes deben maximizar el uso de la Lengua meta, sin duda, hay espacios para que el profesor utilice la lengua materna de los estudiantes en su pedagogía. En este trabajo se presenta un argumento basado en las perspectivas teóricas y la investigación empírica dentro de la literatura existente, apoyando el uso apropiado de la Lengua materna en el salón de inglés como lengua extranjera. El argumento se centra en tres cuestiones fundamentales-racionales para el uso de la lengua materna: Los efectos positivos que la lengua materna tiene tanto en el aprendizaje y la instrucción de una lengua extranjera, como en las formas en las que la lengua materna ayuda a los docentes de idiomas extranjeros.

L1 use is a common occurrence in foreign language teaching contexts despite the fact that it often receives criticism for its interference with target language (TL) acquisition. While foreign language teachers should maximize their use of the TL, there is indeed a place for the teacher to use the students' L1 in their pedagogy. In this paper, an argument derived from theoretical perspectives and empirical research within existing literature supporting the appropriate use of L1 in foreign language classrooms is presented. The argument addresses three key issues-rationales for L1 use, positive effects L1 has on both foreign language learning and instruction, and ways that L1 assists instructors on foreign languages.

En este artículo se plantea el problema de si es apropiado para las universidades o colegios establecer las pruebas de desempeño en lengua extranjera como requisito para la graduación. Se ofrece una revisión histórica de la relación entre la validez y el uso de la prueba. Se presentan ejemplos de cómo evaluar la conveniencia y las consecuencias del uso de estas pruebas para indagar sobre los factores que deben tenerse en cuenta en los procesos de toma de decisiones. Finalmente, se ofrece un modelo que especifica las evidencias que deben recolectarse para apoyar la decisión sobre una prueba válida y sobre un uso mas convincente y beneficioso de las pruebas para los individuos que deben tomarlas.

This paper addresses the issue of whether it is appropriate for universities or junior colleges to set foreign language proficiency requirements for graduation and offers a historical review of the relationship of test validity and test use. Examples of how to evaluate the appropriateness and consequences of test use are presented in order to discover what factors must be taken into account that contributes to the decision-making process. Finally, a model that specifies what evidence needs to be collected in support of a valid test decision is offered to help make decisions of test use more convincing and accordingly more beneficial to those individuals and groups who are affected by the tests.