Investigation of wear behavior of aged and non-aged SiC-reinforced AlSi7Mg2 metal matrix composites in dry sliding conditions

Metal matrix composites (MMCs) with their splendid mechanical properties have been specifically designed for use in fields such as aerospace and aviation. The presence of hard ceramic particles in MMC increases the hardness of the matrix product and decreases its coefficient of friction. Therefore, the wear resistance is improved. Moreover, the mechanical properties of these composite materials can be improved by applying heat treatments. In this study, AlSi7Mg2 MMCs with 15 wt% SiC reinforcement were produced by squeeze casting technique. Some of the composites were aged by heat treatment. Hardness values of aged and non- aged composites were compared. In addition, abrasive wear behaviors of these composites were investigated on pin-on-disk device, depending on the load (7, 12 and 17 N), the sliding speed (0.2, 0.3 and 0.4 m/s) and the sliding distance (700, 1000 and 1300 m). Worn surfaces were also analyzed by scanning electron microscopy (SEM). As a result of the analyses, it was determined that both the hardness values and the wear resistance were higher in the composites subjected to aging treatment. Furthermore, it was observed that the increase in the applied load led up to the weight loss. The increase in the sliding distance increased both friction coefficient and weight loss. The increase in sliding speed also made way for the friction coefficient but ensured less weight loss. When SEM images were examined, it was ascertained that deformation and tribo-surface formation had a significant effect on weight losses

Clinical and laboratory characteristics of women with uterine leiomiyoma

The aim of this study was to compare clinical and laboratory findings of women with or without uterine leiomyoma.Study group consisted of 82 women with uterine leiomyoma and the control group comprised 42 healthy women. Women’s age, gravity, parity, blood groups, pattern of menstrual cycles, complaints at presentation, fertility, ultrasonographical findings, surgical operations and thyroid function tests were evaluated.There were no significant differences in blood group distribution, gravity, parity and thyroid function test results between the patients and the control subjects (P>0.05). A significant difference was found in the complaints at presentation between two groups (P<0.001). Mentrual cycles irregularity was more frequently found in the patients compared with the controls (57.3% vs. 42.9%, respectively, P=0.009). Although no infertile woman was found in the control group, 8.5% of patients were found to have infertility. The sensitivity of ultrasonography was found to be 97.6%. Except for the existence of higher infertility rate and the menstrual cycles irregularities, no significant difference was found in the clinical and laboratory findings between women with or without uterine leiomyoma. Therefore, physical examination and imaging methods are remained as the most important diagnostic tools for uterine leiomyoma

Acute Myeloid Leukemia in a Patient with Ovarian Carcinoma

The occurrence of myelodysplastic syndrome or acute myeloid leukemia has been reported after treatment with cytotoxic alkylating agent-based chemotherapy for solid tumors. We report a 50-year-old woman presented with abdominal distension, vomiting, and fatique. The abdominal tomography showed bilaterally ovarian masses and ascite. Surgery was performed and histopathology of the ovarian mass revealed moderately differentiated papillary adenocarcinoma of ovarian. The patient was treated with chemotherapy combination including paclitaxel and carboplatin for six cycles. At 4 years after chemotherapy, recurrence of the primary disease developed. She received carboplatin and paclitaxel. Two years later, complete blood count showed leukocyte count 15.700 /mm3 (15% myeloblasts), hemoglobin 8.7 g/dL, and platelet count 88.000 /mm3. Bone marrow examination and flow cytometry analysis were consistent with acute myeloid leukemia. Standard induction chemotherapy with idarubicin and cytosine arabinoside was administered with failure to achieve complete remission. At the follow-up, the patient died due to prolonged febrile neutropenia. In conclusion, patients who were treated with high dose or long term alkylating agents should particularly follow-up for secondary tumors

54/07/28 Why Don\u27t Police Quiz Top Suspect: An Editorial

This editorial, published two days after the conclusion of the Coroner\u27s Inquest, describes Sam as a proven liar who is being shielded by his family and demands that he be taken to police headquarters for further questioning. It declares that if average people\u27 were involved in this murder it would have been cleaned up long ago.https://engagedscholarship.csuohio.edu/sheppard_maxwell_articles/1004/thumbnail.jp

First-line treatment of patients with HER2-positive metastatic gastric and gastroesophageal junction cancer

Fluoropyrimidine+cisplatin/oxaliplatin+trastuzumab therapy is recommended for the first-line treatment of HER2-positive metastatic gastric adenocarcinoma. However, there is no comprehensive study on which platinum-based treatment should be preferred. This study aimed to compare the treatment response and survival characteristics of patients with HER2-positive metastatic gastric or gastroesophageal junction (GEJ) cancer who received fluorouracil, oxaliplatin, and leucovorin (mFOLFOX)+trastuzumab or cisplatin and fluorouracil (CF)+trastuzumab as first-line therapy. It was a multicenter, retrospective study of the Turkish Oncology Group, which included 243 patients from 21 oncology centers. There were 113 patients in the mFOLFOX+trastuzumab arm and 130 patients in the CF+trastuzumab arm. The median age was 62 years in the mFOLFOX+trastuzumab arm and 61 years in the CF+trastuzumab arm (P = 0.495). 81.4% of patients in the mFOLFOX+trastuzumab arm and 83.1% in the CF+trastuzumab arm had gastric tumor localization (P = 0.735). The median progression-free survival (PFS) was significantly higher in the mFOLFOX+trastuzumab arm (9.4 months vs. 7.3 months, P = 0.024). The median overall survival (OS) was similar in both groups (18.4 months vs. 15.1 months, P = 0.640). Maintenance trastuzumab was continued after chemotherapy in 101 patients. In this subgroup, the median OS was 23.3 months and the median PFS was 13.3 months. In conclusion, mFOLFOX+trastuzumab is similar to CF+trastuzumab in terms of the median OS, but it is more effective in terms of the median PFS in the first-line treatment of HER2-positive metastatic gastric and GEJ cancer. The choice of treatment should be made by considering the prominent toxicity findings of the chemotherapy regimens

DINAMIC SIMULATION OF HYDAULIC POWER PLANT

Hidrolik santral için dinamik bir modelleme yapılmıştır. Çoğunlukla hidrolik santrallerin bulunduğu ve rezerv elektrik üretimi olarak hidrolik santrallerin kullanıldığı güç sistemimizde hidrolik santrallerin hız kontrol regülatörleri incelenmiştir. Hız regülatörlerinin geçici hız eğimi özellikleri ve gereksinimi ile hız regülatörü stabilitesi simüle edilerek geçici hız eğimi değer aralıklarının tespiti yapılmıştır. Ayrıca, hız regülatörlerinin sıfırlama (reset) süresi ve servo motor kazanç sabitinin hız kontrolünü ne şekilde etkilediği simülasyonlar ile irdelenmiştir. izmir gundem komik videolar cizgi film izle cizgi film 3d oyunlar oyunlar Speed Control governors of hydraulic power plants, performing significant part of our power system and used also as reserve units, are investigated by means of dynamic modelling of hydraulic power plant. Properties of and requirement of temporary droop and ranges of temporary droop are carried out by simulating stability of frequency control. Moreover, how reset time and servo motor gain constant of governor affect speed control is searched by mode of simulations