Impact Fatigue Characteristics of Valve Leaves for Small Hermetic Reciprocating Compressors

This paper presents an investigation on the impact fatigue characteristics of valve leaves that are prevalently used in hermetic reciprocating compressors especially for the household type refrigerators. The investigation relates the impact fatigue lifetime of the valve leaves that is the heart of the compressor, with the working temperature, material type (carbon steel, stainless steel and improved stainless steel grade) and tumbling duration after the manufacturing process. The investigation provides a better understanding of the impact fatigue characteristics of valve leaves while designing a high performance compressor to decrease the energy consumption. \ud A unique automated impact fatigue test system was designed and produced, which enables to carry out impact fatigue tests of the compressor valve leaves under the desired impact velocities. In the test system, original valve plate and valve leaf couple was utilized through the experimentation in order to simulate the real behavior in the compressor. A fixture was designed to mount the valve plate. The main principle of the system is to create pulsating airflow through a high frequency solenoid valve. The impact fatigue life was determined for various impact velocities and at different operating temperatures

An investigation on the impact fatigue characteristics of valve leaves for small hermetic reciprocating compressors in a new automated test system

This paper presents an investigation on the impact fatigue characteristics of valve leaves that are prevalently used in hermetic reciprocating compressors especially for the household type refrigerators. A unique automated impact fatigue test system has been designed and produced, which enables to carry out impact fatigue tests of the compressor valve leaves under the desired impact velocities. The test system serves investigations on the impact fatigue characteristics with the ability of crack detection and as the subsequent step of automatically terminating the test. The crack detection technique incorporates a non-contact actuation, a data acquisition system and a microphone. The investigation relates the impact fatigue lifetime of the valve leaves with the impact velocity, asymmetrical impact, operation temperature, material type (carbon strip steel, stainless strip steel and new stainless strip steel grade) and tumbling operation duration. Microscopic and metallographic observations were performed on the specimens. It was observed that the crack initiated at the edge of the valve leaves on the contact surface of valve leaf and vale plate and a particle is torn away from the edge before propagation. As the crack propagates, branching along the crack path is caused by the geometrical shape and stress waves on the valve leaves. The investigation and introduced test system guide the design optimization of valve leaves in terms of compressor performance due to energy consumption and lifetime of the valve leaf

Original Article Expression of fibroblast growth factor receptor 1, fibroblast growth factor 2, phosphatidyl inositol 3 phosphate kinase and their clinical and prognostic significance in early and advanced stage of squamous cell carcinoma of the lung

Abstract: Aim: Non-small cell lung carcinoma is the leading cause of cancer related to death in the world. Squamous cell lung carcinoma (SqCLC) is the second most frequent histological subtype of lung carcinomas. Recently, growth factors, growth factor receptors, and signal transduction system-related gene amplifications and mutations are extensively under investigation to estimate the prognosis and to develop individualized therapies in SqCLC. In this study, besides the signal transduction molecule phosphatidyl inositol-3-phosphate kinase (IP3K) p110α, we explored the expressions of fibroblast growth factor 2 (FGF2) and receptor-1 (FGFR1) in tumor tissue and also their clinical and prognostic significance in patients with early/advanced SqCLC. Materials and methods: From 2005 to 2013, 129 patients (23 early, 106 advanced disease) with a histopathological SqCLC diagnosis were selected from the hospital files of Cukurova University Medical Faculty for this study. Two independent pathologists evaluated FGFR1, FGF2, and PI3K (p110α) expressions in both tumor and stromal tissues from 99 of the patients with sufficient tissue samples, using immunohistochemistry. Considering survival analysis separately for patients with both early and advanced stage diseases, the relationship between the clinical features of the patients and expressions were evaluated by univariate and multivariate analyses. Results: FGFR1 expression was found to be low in 59 (60%) patients and high in 40 (40%) patients. For FGF2; 12 (12%) patients had high, 87 (88%) patients had low expression and for IP3K; 31 (32%) patients had high and 66 (68%) patients had low expressions. In univariate analysis, overall survival (OS) was significantly associated with stage of the disease and the performance status of the patient (P<0.0001 and P<0.001). There was no significant difference in OS of the patients with either low or high expressions of FGFR1, FGF2, and IP3K. When the patients with early or advanced stage disease were separately taken into consideration, the relationship did not differ, either. Any of FGFR1, FGF2 or IP3K expressions was not found predictive for the treatment of early or advanced staged patients. On the other hand, the expressions of both FGFR1 and FGF2 were significantly different with respect to smoking, scar of tuberculosis and scar of radiotherapy (P=0.002; P=0.06 and P=0.05, respectively). Discussion: There has not been identified an effective individualized treatment for SqCLC yet. Therefore, in order to be able to develop such a treatment in the future, it is essential to identify the genetic abnormalities that are responsible for the biological behaviors and carcinogenesis of SqCLC. Although we could not show the prognostic and predictive significance of FGFR1, FGF2 and IP3K expressions in SqCLC, we determined the expression rates of FGFR1, FGF2 and IP3K as a reference for Turkish patients. In conclusion, we want to put some emphasis on the fact that, pulmonary fibrosis which is a late complication of radiotherapy at stage III disease, and the scar of tuberculosis could be associated with FGFR1 and FGF2 expressions

Operational Research: Methods and Applications

Throughout its history, Operational Research has evolved to include a variety of methods, models and algorithms that have been applied to a diverse and wide range of contexts. This encyclopedic article consists of two main sections: methods and applications. The first aims to summarise the up-to-date knowledge and provide an overview of the state-of-the-art methods and key developments in the various subdomains of the field. The second offers a wide-ranging list of areas where Operational Research has been applied. The article is meant to be read in a nonlinear fashion. It should be used as a point of reference or first-port-of-call for a diverse pool of readers: academics, researchers, students, and practitioners. The entries within the methods and applications sections are presented in alphabetical order

The Relationships Between Children's Prosocial-Lie Telling Behavior, Theory of Mind and Executive Functions in 54-66 Months

This research examined the relationship between prosocial lie-telling behavior, theory of mind, and executive functions in children aged 54-66 months. The sample consists of 96 children (54 boys, 42 girls) aged 54-66 months (4.5-5.5 years) enrolled at five public schools and private schools in Istanbul. The children's prosocial lie-telling behavior is tested by the good and bad drawing task and the dissapointing gift paradigm. Two false belief tasks and one appearance-reality task were used to measure theory of mind (ToM). Along with the measures for theory of mind, working memory, cognitive flexibility, and inhitory control were measured by the dimensional change card sort (DCCS) and day-night Strooplike test, respectively. As a result, there was no significant differences between the children's cognitive scores (ToM, DCCS, Stroop) and pro-social lying tasks. However, there were significant predictive relationships with the DCCS and the disappointing gift paradigm's swap condition. When age was controlled, Stroop and prosocial lie-telling in the good and bad drawing task correlated significantly in young children. White-lie-telling scores are differentiated, according to researchers, in older children. Thus, it is thought that social and motivational factors may affects children's prosocial behavior. In this study, the disappointing gifts paradigm and good and bad drawing tasks were used to measure children's prosocial lie-telling behavior, and it was discovered that there were quite different values for children's lying rates

Expression of soluble CD27 and interleukins-8 and-10 in B-cell chronic lymphocytic leukemia: Correlation with disease stage and prognosis

WOS: 000246229900004PubMed ID: 17526459Investigators in this study explored levels of soluble CD27 (sCD27), interleukin (IL)-8, and IL-10 in B-cell chronic lymphocytic leukemia (B-CLL), and the correlation of these levels with disease stage and prognosis. Plasma IL-8, IL-10, and sCD27 levels were assessed with enzyme-linked immunosorbent assay tests in 22 healthy donors and 70 patients with B-CLL (49 men and 21 women). Mean patient age was 61.57 y (range, 44-75 y). Mean healthy donor age was 62.09 y (range, 40-72 y). in the study group, mean values were as follows: plasma L-8, 284.758 pg/mL (0-1000 pg/mL); plasma IL-10, 26.152 pg/mL (0-100 pg/mL); sCD27, 731.357 U/mL (139.9-1000 U/mL); white blood cell count, 59.9 x 10(9)/L (0.8-250.0 x 10(9)/L); hemoglobin count, 11.2 g/dL (5.0-16.2 g/dL); platelet count, 162.5 x 10(9)/L (2 9.8-317 x 10(9)/L); 132 microglobulin (B2M) 3350.2 mg/L (274.7-7499.9 mg/L); CD38, 19.50%; and lactate dehydrogenase (count, 497.5 U/L (263.0-1507 U/L). Patients represented all Rai stages, with 22.9%, at stage 0, 11.4% at stage 1, 11.4% at stage 11, 41.4%, at stage 111, and 12.9% at stage IV. Plasma levels of IL-8, IL-10, and sCD27 were correlated between study and control groups; significantly higher IL-8 (P=.001) and sCD27 (P=.000) levels were found, but the IL-10 level was not significant (P=.l 39). Plasma IL-10 (P=.01) and sCD27 (P=.008) were positively correlated with Rai stage, but IL-8 was not (P=. 146). Levels of sCD27 were significantly correlated with values for 132 M (P=.000), hemoglobin (P=.028), lactate dehydrogenase (P=.001), CD19 (P=.03), and IL-10 (P=.000). IL-8 was significantly correlated with white blood cell (P=.000) count, and CD38 (P=.001) and CD5 (P=.006) levels. IL-10 was significantly correlated with B-2,M (P=.01 7), CD1 9 (P=.000), platelet (P=.002), and CD27 (P=.000). In survival distributions for CD27, IL-8 and IL-10 were found to have more significant relationships for all parameters (P=.0000). In conclusion, the authors suggest that sCD27, IL-8, and IL-10 are more significant prognostic factors for B-CLL when compared with others, and these values should correlate with new prognostic factors (eg, zeta-associated protein-70, mutated/unmutated immunoglobulin variable heavy chain)

Retrospective Analysis of Cancer with Behcets Disease: Single Center Experience

Purpose: Behcets disease (BD) is a vasculitis of unknown origin. In autoimmune and vasculitic disorders the risk of malignancies has been extensively studied. In BD patients more than hundred cases associated with malignancies have been published. However, the direct relationship with BD has not been proved. We aimed to to investigate the incidence of malignancies in BD patients Material and Methods: Here in we assessed 105 cases retrospectively between 2005-2010 with BD diagnosed according to International Study Criteria (ISG) . The patient’s data were reviewed for development of histopathologically confirmed malignancy Results: One of our 105 patients with BD was found to have solid tumor in the rate of 0.9 %. The remaining 104 patients with BD were in follow up without any malignancy in this period. The malignancy that we reported was invasive right breast carcinoma in a 55-year-old woman with BD. A radically modified right mastectomy and axillary lymphadenectomy were performed and postoperative doxorubicin, cyclophosphamide therapy for four cycles and hormonal therapy with tamoxifen and leuprolide acetate was administered as adjuvant therapy. This patient had a history of 16 years colchicine usage as medication for BD. Conclusion:The rheumatologic diseases can predispose malignancy, the autoimmune nature of BD or the immunosupressive medicines could be possible causes of this carcinoma. However, in our study only one patient had malignancy. The another point of view; management and also prevention of cancer with BD is important entity