IMECE2005-82993 MONTE CARLO SCHEMES FOR RADIATIVE TRANSFER IN MEDIA REPRESENTED BY PARTICLE FIELDS

ABSTRACT Monte Carlo ray-tracing schemes are developed for the evaluation of radiative heat transfer for problems, in which the participating medium is represented by discrete point-masses, such as the ow eld and scalar elds in PDF Monte Carlo methods frequently used in combustion modeling. Photon ray tracing in such cases requires that an optical thickness is assigned to each of the point-masses. Two approaches are discussed, the Point Particle Model (PPM), in which the shape of particle is not speci ed, and the Spherical Particle Model (SPM) in which particles are assumed to be spheres with constant radiation properties. Another issue for ray tracing in particle elds is the in uence region of a ray. Two ways of modeling a ray are proposed. In the rst, each ray is treated as a standard volume-less line. In the other approach, the ray is assigned a small solid angle, and is thus treated as a cone with a decaying in uence function away from its center line. Based on these models, three different interaction schemes between rays and particles are proposed, i.e., Line-SPM, Cone-PPM and Cone-SPM methods, and are compared employing several test problems

Experimental Study on Kaiser Effect of Reinforced Concrete Simply-Supported Beams

With the progress of transportation, an increasing number of bridges are put into operation, and the assessment of bridge bearing capacity is considered a significant measure to ensure bridge safety. As a critical approach for structural monitoring, acoustic emission is widely used in engineering projects. Since the Kaiser effect is an important phenomenon in acoustic emission, it is necessary to explore the Kaiser effect of reinforced concrete structures and the determination method of the Kaiser point. In this thesis, four reinforced concrete simply supported beams were utilized for the graded loading experiment under bending loads. After accumulating acoustic emission parameters, Kaiser point was selected for preliminary evaluation. Taking Kaiser point as the midpoint, the appropriate interval was determined. According to the continuity criterion of acoustic emission signals and the quadratic fitting curve based on experimental data, the Kaiser point was corrected by following the average growth rate of acoustic emission parameters. These simply supported beams were classified into two groups. One group was used to explore the acoustic emission characteristics when the load was less than the historical maximum, while the other group was used to analyze changes in the Kaiser effect with increasing load. Finally, based on the results of the specimen inspection, the influence of initial damage on the Kaiser effect was analyzed. The research results alleviated the influence of human factors on the determination of the Kaiser point and can serve as the theoretical basis for damage monitoring based on the Kaiser effect and bearing capacity evaluation of reinforced concrete structures

Outer membrane vesicles from bacteria: Role and potential value in the pathogenesis of chronic respiratory diseases

Infectious diseases are the leading cause of death in both adults and children, with respiratory infections being the leading cause of death. A growing body of evidence suggests that bacterially released extracellular membrane vesicles play an important role in bacterial pathogenicity by targeting and (de)regulating host cells through the delivery of nucleic acids, proteins, lipids, and carbohydrates. Among the many factors contributing to bacterial pathogenicity are the outer membrane vesicles produced by the bacteria themselves. Bacterial membrane vesicles are being studied in more detail because of their potential role as deleterious mediators in bacterial infections. This review provides an overview of the most current information on the emerging role of bacterial membrane vesicles in the pathophysiology of pneumonia and its complications and their adoption as promising targets for future preventive and therapeutic approaches

Bronchoalveolar Lavage Fluid-Derived Exosomes: A Novel Role Contributing to Lung Cancer Growth

Exosomes are nanovesicles produced by a number of different cell types and regarded as important mediators of cell-to-cell communication. Although bronchoalveolar lavage fluid (BALF) has been shown to be involved in the development of tumors, its role in lung cancer (LC) remains unclear. In this article, we systemically studied BALF-derived exosomes in LC. C57BL/6 mice were injected with Lewis lung carcinoma cells and exposed to non-typeable Haemophilus influenza (NTHi) lysate. The analysis showed that the growth of lung tumors in these mice was significantly enhanced compared with the control cohort (only exposure to air). Characterization of the exosomes derived from mouse BALF demonstrated elevated levels of tumor necrosis factor alpha and interleukin-6 in mice exposed to NTHi lysates. Furthermore, abnormal BALF-derived exosomes facilitated the development of LC in vitro and in vivo. The internalization of the BALF-derived exosomes contributed to the development of LC tumors. Collectively, our data demonstrated that exosomes in BALF are a key factor involved in the growth and progression of lung cancer

A Two-Level Hierarchical Linear Model Analysis of the Effect of Teacher Factors, Student Factors, and Facility Conditions on Students’ Cognitive Scores in Rural China

Based on the data from the China Education Panel Survey 2013–2014, this study uses a two-level hierarchical linear model to explore the impact of student factors, teacher factors, and facility conditions on students’ cognitive scores and the model’s heterogeneity. Additionally, under the Owen value method, the contribution of teacher and student factors to students’ cognitive scores is much greater than that of facility conditions, and teacher-related factors contribute more to scores than student-related ones. Therefore, teacher and student resources should be given priority in allocating resources to rural education systems, and high-quality teachers, who can have positive impacts on students’ cognitive scores, should be prioritized

A Two-Level Hierarchical Linear Model Analysis of the Effect of Teacher Factors, Student Factors, and Facility Conditions on Students’ Cognitive Scores in Rural China

Based on the data from the China Education Panel Survey 2013–2014, this study uses a two-level hierarchical linear model to explore the impact of student factors, teacher factors, and facility conditions on students’ cognitive scores and the model’s heterogeneity. Additionally, under the Owen value method, the contribution of teacher and student factors to students’ cognitive scores is much greater than that of facility conditions, and teacher-related factors contribute more to scores than student-related ones. Therefore, teacher and student resources should be given priority in allocating resources to rural education systems, and high-quality teachers, who can have positive impacts on students’ cognitive scores, should be prioritized