MOLTEN ALUMINUM CAPILLARY HOLE-FILLING

The presence of micrometeoroids and space debris in open space raises the question of a mitigation of the damage caused by a possible impact on the man-made structures such as space shuttles, satellites, and the International Space Station. A method achieving metallic sealed hole would be of an interest for development. This dissertation studies a surface tension driven capillary filling/sealing phenomenon in a controlled atmosphere brazing process of aluminum. The filled vs. non-filled results are predictable using minimization of energy, which shows that the outcomes depend heavily on prescribed configurations of the hole. Equilibrium models show excellent agreement with experimental results. It has been concluded that to fill an open hole by liquid aluminum in surface tension dominant cases, a deeper and narrower hole is favorable for a successful filling. To facilitate the filling process, the ability of liquid to migrate through edges is essential and has been shown experimentally in both aluminum brazing case and the benchmark silicone-oil/polystyrene system. The amount of liquid formed from the cladding layer has been evaluated and is not the limiting factor for filled/non-filled outcomes in discussed configurations

JOINT FORMATION UNDER SEVERELY ALTERED BACKGROUND ATMOSPHERE IN CONTROLLED ATMOSPHERE BRAZING OF ALUMINUM

Adverse changes of background atmosphere in a brazing chamber cause qualitative and quantitative deterioration of joint formation in an aluminum brazing process. This study offers an insight into the adverse effects with gradually adjusted atmospheric conditions in terms of oxygen and humidity levels. Corresponding responses of the molten clad flow and the joint formation upon resolidification vs. atmospheric conditions are documented by comparative tests involving self-fluxing and surface-fluxing brazing sheets: 1) in situ and in real time study of the onset of melting, clad flow, and joint formation, and 2) inclined wedge-tee mating tests for brazeability assessment. The surface-fluxing brazing sheet in series of tests was covered with potassium fluoroaluminate flux, while the self-fluxing brazing sheet with the composite material was executed without extra flux addition. Typical outcomes of joint formation under adverse atmosphere including smaller joint size, non-uniform joint formation, in-completed joining area, and no joint formation were documented. Transitional behavior of deteriorating joint formation is observed in increasing oxygen and humidity levels. The self-fluxing material demonstrated a remarkable resilience against an adverse atmospheric impact comparing to the surface-fluxing material

A QFD-Based Mathematical Model for New Product Development Considering the Target Market Segment

Responding to customer needs is important for business success. Quality function deployment provides systematic procedures for converting customer needs into technical requirements to ensure maximum customer satisfaction. The existing literature mainly focuses on the achievement of maximum customer satisfaction under a budgetary limit via mathematical models. The market goal of the new product for the target market segment is usually ignored. In this study, the proposed approach thus considers the target customer satisfaction degree for the target market segment in the model by formulating the overall customer satisfaction as a function of the quality level. In addition, the proposed approach emphasizes the cost-effectiveness concept in the design stage via the achievement of the target customer satisfaction degree using the minimal total cost. A numerical example is used to demonstrate the applicability of the proposed approach and its characteristics are discussed

Membrane repair against H. pylori promotes cancer cell proliferation

Membrane repair is a universal response against physical and biological insults and enables cell survival. Helicobacter pylori is one of the most common human pathogens and the first formally recognized bacterial carcinogen associated with gastric cancer. However, little is known about host membrane repair in the context of H. pylori infection. Here we show that H. pylori disrupts the host plasma membrane and induces Ca2+ influx, which triggers the translocation of annexin family members A1 and A4 to the plasma membrane. This in turn activates a membrane repair response through the recruitment of lysosomal membranes and the induction of downstream signaling transduction pathways that promote cell survival and proliferation. Based on our data, we propose a new model by which H. pylori infection activates annexin A1 and A4 for membrane repair and how annexin A4 over-expression induced signaling promotes cell proliferation. Continual activation of this membrane repair response signaling cascade may cause abnormal cellular states leading to carcinogenesis. This study links H. pylori infection to membrane repair, providing insight into potential mechanisms of carcinogenesis resulting from membrane damage

THE RELATIONSHIP BETWEEN SHOULDER PAIN AND SCAPULAR MOBILITY IN TEENAGE BASEBALL PLAYERS

The purpose of this study was to identify the relationship between shoulder pain and scapular mobility for teenage baseball players. Thirty-five teenage baseball players (shoulder pain, n=11; healthy, n=24) were recruited in this study. The lateral scapula slide test (LSST), which represented as scapular mobility, was used to measure the scapular position and symmetry under varying loads. The result of this study showed that there was a difference in distance from the superior angle of the scapula to the spinous process of T2 between the two groups at shoulder 90?abduction

Effect of end-stage renal disease on long-term survival after a first-ever mechanical ventilation: a population-based study

The 30-day, 6-month, and 1-, 2-, 5-, and 10-year survival rate differences in the ESRD Pos and ESRD Neg groups from the beginning. (DOCX 17 kb

QUANTITATIVE ANALYSIS OF THE DYNAMIC BALANCE ABILITY BETWEEN THE COLLEGE STUDENTS AND HANDBALL PLAYERS

The purpose of this study was to investigate the differences of dynamic standing ability (Balance keeping time; BKT) and the change of the angular velocity (deg. / s) of a platform between healthy non-athelete female students and handball players using an unstable platform-like seesaw. Methods: The seesaw is capable of rotating side to side in both directions of right and left; it was set horizontally at an angle of zero degrees as a base, with the maximum degree of the seesaw inclination set at 25 degrees. In addition, a high-speed digital video camera (SONY-HDR-CX520V) was set to record the BKT and the changes of motion in the frontal plane from both sides of the plate. Results: There is a significant difference observed in both BKT and the change of angular velocity between non-athletes and handball players. Conclusion: The findings suggest the data gained from the experiments may establish a dynamic balance fitness norm and can be used as an assessment method of the lower extremity coordination ability

Integrative network analysis reveals active microRNAs and their functions in gastric cancer

<p>Abstract</p> <p>Background</p> <p>MicroRNAs (miRNAs) are a class of endogenous, small and highly conserved noncoding RNAs that control gene expression either by degradation of target mRNAs or by inhibition of protein translation. They play important roles in cancer progression. A single miRNA can provoke a chain reaction and further affect protein interaction network (PIN). Therefore, we developed a novel integrative approach to identify the functional roles and the regulated PIN of oncomirs.</p> <p>Results</p> <p>We integrated the expression profiles of miRNA and mRNA with the human PIN to reveal miRNA-regulated PIN in specific biological conditions. The potential functions of miRNAs were determined by functional enrichment analysis and the activities of miRNA-regulated PINs were evaluated by the co-expression of protein-protein interactions (PPIs). The function of a specific miRNA, miR-148a, was further examined by clinical data analysis and cell-based experiments. We uncovered several miRNA-regulated networks which were enriched with functions related to cancer progression. One miRNA, miR-148a, was identified and its function is to decrease tumor proliferation and metastasis through its regulated PIN. Furthermore, we found that miR-148a could reduce the invasiveness, migratory and adhesive activities of gastric tumor cells. Most importantly, elevated miR-148a level in gastric cancer tissues was strongly correlated with distant metastasis, organ and peritoneal invasion and reduced survival rate.</p> <p>Conclusions</p> <p>This study provides a novel method to identify active oncomirs and their potential functions in gastric cancer progression. The present data suggest that miR-148a could be a potential prognostic biomarker of gastric cancer and function as a tumor suppressor through repressing the activity of its regulated PIN.</p