Determination of Optimum Compression Ratio: A Tribological Aspect

Internal combustion engines are the primary energy conversion machines both in industry and transportation. Modern technologies are being implemented to engines to fulfill today's low fuel consumption demand. Friction energy consumed by the rubbing parts of the engines are becoming an important parameter for higher fuel efficiency. Rate of friction loss is primarily affected by sliding speed and the load acting upon rubbing surfaces. Compression ratio is the main parameter that increases the peak cylinder pressure and hence normal load on components. Aim of this study is to investigate the effect of compression ratio on total friction loss of a diesel engine. A variable compression ratio diesel engine was operated at four different compression ratios which were "12.96", "15:59", "18:03", "20:17". Brake power and speed was kept constant at predefined value while measuring the in- cylinder pressure. Friction mean effective pressure ( FMEP ) data were obtained from the in cylinder pressure curves for each compression ratio. Ratio of friction power to indicated power of the engine was increased from 22.83% to 37.06% with varying compression ratio from 12.96 to 20:17. Considering the thermal efficiency , FMEP and maximum in- cylinder pressure optimum compression ratio interval of the test engine was determined as 18.8 ÷ 19.6

Common extensor origin release in recalcitrant lateral epicondylitis - role justified?

The aim of our study was to analyse the efficacy of operative management in recalcitrant lateral epicondylitis of elbow. Forty patients included in this study were referred by general practitioners with a diagnosis of tennis elbow to the orthopaedic department at a district general hospital over a five year period. All had two or more steroid injections at the tender spot, without permanent relief of pain. All subsequently underwent simple fasciotomy of the extensor origin. Of forty patients thirty five had improvement in pain and function, two had persistent symptoms and three did not perceive any improvement. Twenty five had excellent, ten had well, two had fair and three had poor outcomes (recurrent problem; pain at rest and night). Two patients underwent revision surgery. Majority of the patients had improvement in pain and function following operative treatment. In this study, an extensor fasciotomy was demonstrated to be an effective treatment for refractory chronic lateral epicondylitis; however, further studies are warranted

Seroprevalence and risk factors for toxoplasma infection among pregnant women in Aydin province, Turkey

BACKGROUND: The aims of the present study were to determine the prevalence of toxoplasmosis in pregnant women at first trimester of their pregnancy and to follow up the seroconversion for next two trimesters, and to identify the risk factors and possible contamination routes in Aydin province, Turkey. METHOD: The sample size was calculated as 423 on a prevalence of 50%, d=0.05 at a confidence level of 95% with 10% addition. It was a cross-sectional study with multistage sampling. After a questionnaire applied to the pregnant women, anti-Toxoplasma IgG antibodies were studied with ELISA and IFA, values in conflict with DA test, where IgM antibodies were studied with ELISA and for borderline or positive values of IgM avidity test was used. RESULTS: The mean age of 389 (92.9%) of pregnant women in the study was 24.28+/-4.56 years, the seroprevalence of anti-Toxoplasma IgG antibodies for toxoplasmosis was 30.1%. Seroprevalence was increased with age (p=0.001) and with drinking water consumption other than bottled water (p=0.042). No significant relations were observed between anti-Toxoplasma IgG antibodies and education level, being native or migrant, abortion history, consumption of meat, vegetable and milk/milk products, personal or kitchen hygiene habits, cat owning at home of the pregnant women. No IgM antibody was detected. CONCLUSION: One of every three pregnant women in Aydin was at risk of toxoplasmosis at the first trimester of their pregnancy. Increased seroprevalance with age was a predictable result because of increasing time of exposure. Increased seroprevalence with consumption of municipal and uncontrolled water (well/spring water) supplies was similar with latest epidemiological findings

Editorial of Special Issue of National Identities: Alevism as an ethno-religious identity: Contested boundaries

No abstract for editorial but this is the opening paragraph: This special issue on Alevism and trans/national Alevi identity critically engages with the relationship between religion, ethnicity and national identity. The core issues are as follows: • how ethnicity and religion are conceptualised for a relatively invisible ethnic group in different national contexts; • how religion and ethnicity intersect when Alevism is both a faith and an ethnic identity, especially when conceptions of that identity are contested; • how identity is shaped through state policies within different national policy contexts and how etic definitions of minority communities are constructed by the state or other agencies with the power to impose them on the community in contrast to the emic or self-definitions of Aleviness from within the Alevi community; • how despite the fragmented, heterogeneous nature of Alevi communities, there is also a sense of a single, transnational imaginary community, at least for the purposes of political assimilation/integration and activism; • how education and other arenas of political, religious and cultural engagement at local, national and transnational levels create the possibilities, both positively and negatively, for future action/policy to situate minority ethnic communities

Systemic and local antibiotic prophylaxis in the prevention of Staphylococcus epidermidis graft infection

BACKGROUND: The aim of the study was to investigate the in vivo efficacy of local and systemic antibiotic prophylaxis in the prevention of Staphylococcus (S.) epidermidis graft infection in a rat model and to evaluate the bacterial adherence to frequently used prosthetic graft materials. METHODS: Graft infections were established in the subcutaneous tissue of 120 male Wistar rats by implantation of Dacron/ePTFE grafts followed by topical inoculation with 2 × 10(7 )CFUs of clinical isolate of methicillin-resistant S. epidermidis. Each of the graft series included a control group, one contaminated group that did not receive any antibiotic prophylaxis, two contaminated groups that received systemic prophylaxis with teicoplanin or levofloxacin and two contaminated groups that received teicoplanin-soaked or levofloxacin-soaked grafts. The grafts were removed 7 days after implantation and evaluated by quantitative culture. RESULTS: There was significant bacterial growth inhibition in the groups given systemic or local prophylaxis (P < 0.05). Methicillin-resistant S. epidermidis had greater affinity to Dacron graft when compared with ePTFE graft in the untreated contaminated groups (P < 0.05). CONCLUSION: The study demonstrated that the usage of systemic or local prophylaxis and preference of ePTFE graft can be useful in reducing the risk of vascular graft infections caused by staphylococcal strains with high levels of resistance

mTOR Controls Ovarian Follicle Growth by Regulating Granulosa Cell Proliferation

We have shown that inhibition of mTOR in granulosa cells and ovarian follicles results in compromised granulosa proliferation and reduced follicle growth. Further analysis here using spontaneously immortalized rat granulosa cells has revealed that mTOR pathway activity is enhanced during M-phase of the cell cycle. mTOR specific phosphorylation of p70S6 kinase and 4E-BP, and expression of Raptor are all enhanced during M-phase. The predominant effect of mTOR inhibition by the specific inhibitor Rapamycin (RAP) was a dose-responsive arrest in the G1 cell cycle stage. The fraction of granulosa cells that continued to divide in the presence of RAP exhibited a dose-dependent increase in aberrant mitotic figures known as anaphase bridges. Strikingly, estradiol consistently decreased the incidence of aberrant mitotic figures. In mice treated with RAP, the mitotic index was reduced compared to controls, and a similar increase in aberrant mitotic events was noted. RAP injected during a superovulation regime resulted in a dose-dependent reduction in the numbers of eggs ovulated. Implications for the real-time regulation of follicle growth and dominance, including the consequences of increased numbers of aneuploid granulosa cells, are discussed

New Universal Tribometer as Pin or Ball-on-Disc and Reciprocating Pin-on-Plate Types

The present paper contains a description of a new Universal Tribometer design which enables simulation of different contact and test types such as pin-on-disc, ball-on-disc and linear reciprocating tests. There are many models of wear Tribometer in the world market. These devices are manufactured by various companies abroad and are imported to our country. Cost of this devices start from 50.000 euros and goes to hundreds of thousands of euros. One of the most commonly used of this device is Reciprocating Pin-on-Plate Tribo Test Machine. This wear tester is produced at a low limited cost within the KAP (Scientifical Research Project Coordinator) of Yıldız Technical University. The test machine can work including three types of Tribotest rigs (Reciprocating Pin-on-Plate, Pin-on-Disc and Ball-on-Disc). It is designed to operate also at high temperatures up to 500 ˚C. The new piece of equipment allows instrumented tribological testing of piston ring and cylinder liner samples at low and high temperatures and boundary lubrication conditions of any typical gasoline or Diesel engines. Some friction results were shown in boundary lubricating conditions between piston ring and cylinder liner sliding pairs describing Tribotest machine is driven by AC servo motor which is more accurate than DC motor

Investigation of mold fungi in air samples of elementary schools and evaluation of allergen-specific IgE levels in students' sera

Atmospheric fungal spores play important role in allergic reactions in atopic individuals. Monitorization of those spores found in the environment of atopic cases is crucial for the choice of the antigens that will be included in allergen screening procedures and precautions to be taken against mold-originated health problems. Since most of the people spend plenty of time indoors in recent years, the effects of exposure to indoor air fungi on human health have gained importance. This study was aimed to investigate the indoor air mold distribution of elementary schools in Denizli province (located in west Anatolia, Turkey) and to compare the allergen-specific IgE levels of children against the most frequently detected mold genus. A questionnaire (MM080) was distributed to the 4967 students (6-8 year-old) attending first and second degrees of 16 different elementary schools with scattered locations in city center. This questionnaire form included the questions related to the general information about the child, school environment, allergic complaints since last year, home environment and nutrition. Response rate to the questionnaire was 51.6% (2565/4967). Air samples were collected from 18 classrooms in March 2009, during which high rates of allergic symptoms were observed according to the questionnaire results. Mold fungi belonging to 10 different genera (Pénicillium spp. 46%; Aspergillus spp. 18%; Cladosporium spp. 17%; Alternaria spp. 15%; Drechslern spp. 1 %; Chrysosporium, Fusarium, Conidiobolus and Cladathecium species 0.5%; unidentified 1%) were isolated from indoor air of classrooms. Since the most frequently detected mold was Pénicillium spp. (46%), the 48 children with atopic symptoms were called to the hospital for the determination of total IgE and Pénicillium specific IgE in their sera. Twenty two students accepted the invitation and serum total IgE (Immulite 2000; Diagnostic Product Corporation, USA) and allergen-specific IgE (Pénicillium brevicompactum, Pénicillium camemberti, Pénicillium chrysogenum, Pénicillium commune, Pénicillium expansum, Pénicillium fréquentons, Pénicillium glaucum, Pénicillium notatum, Pénicillium roquefortivz Pénicillium viridicatum) (RIDASCREEN; R-Biopharm AG, Germany) levels were determined in those children. Total IgE levels above reference ranges were detected in 41 % (9/22) of the screened sera samples. P.roqueforti, P.commune and P.camemberti antibodies were higher (Odds ratio as 5.50, 4.0 and 3.75, respectively) in sera with high total IgE levels. No independent variables were determined between individual and/or environmental factors and Penicillium-specific IgE antibodies. It was concluded that those three strains should be chosen as antigens for mold allergy screening tests which will be performed among atopic cases in our region. In conclusion it should be kept in mind that molds have a possible role in the development of allergic symptoms, however, they are not the sole determining factor in this process. In the investigation of the allergic diseases environmental factors should be considered and standardized methods should be applied

Evaluation of Allergen-Specific IgE Levels in Students' Sera

Atmospheric fungal spores play important role in allergic reactions in atopic individuals. Monitorization of those spores found in the environment of atopic cases is crucial for the choice of the antigens that will be included in allergen screening procedures and precautions to be taken against mold-originated health problems. Since most of the people spend plenty of time indoors in recent years, the effects of exposure to indoor air fungi on human health have gained importance. This study was aimed to investigate the indoor air mold distribution of elementary schools in Denizli province (located in west Anatolia, Turkey) and to compare the allergen-specific IgE levels of children against the most frequently detected mold genus. A questionnaire (MM080) was distributed to the 4967 students (6-8 year-old) attending first and second degrees of 16 different elementary schools with scattered locations in city center. This questionnaire form included the questions related to the general information about the child, school environment, allergic complaints since last year, home environment and nutrition. Response rate to the questionnaire was 51.6% (2565/4967). Air samples were collected from 18 classrooms in March 2009, during which high rates of allergic symptoms were observed according to the questionnaire results. Mold fungi belonging to 10 different genera (Penicillium spp. 46%; Aspergillus spp. 18%; Cladosporium spp. 17%; Alternaria spp. 15%; Drechslera spp. 1%; Chtysosporium, Fusarium, Conidiobolus and Cladothecium species 0.5%; unidentified 1%) were isolated from indoor air of classrooms. Since the most frequently detected mold was Penicillium spp. (46%), the 48 children with atopic symptoms were called to the hospital for the determination of total IgE and Penicillium specific IgE in their sera. Twenty two students accepted the invitation and serum total IgE (Immulite 2000; Diagnostic Product Corporation, USA) and allergen-specific IgE (Penicillium brevicompactum, Penicillium camemberti, Penicillium chrysogenum, Penicillium commune, Penicillium expansum, Penicillium frequentans, Penicillium glaucum, Penicillium notatum, Penicillium roqueforti ve Penicillium viridicatum) (RIDASCREEN; R-Biopharm AG, Germany) levels were determined in those children. Total IgE levels above reference ranges were detected in 41% (9/22) of the screened sera samples. P.roqueforti, P.commune and P.camemberti antibodies were higher (Odds ratio as 5.50, 4.0 and 3.75, respectively) in sera with high total IgE levels. No independent variables were determined between individual and/or environmental factors and Penicillium-specific IgE antibodies. It was concluded that those three strains should be chosen as antigens for mold allergy screening tests which will be performed among atopic cases in our region. In conclusion it should be kept in mind that molds have a possible role in the development of allergic symptoms, however, they are not the sole determining factor in this process. In the investigation of the allergic diseases environmental factors should be considered and standardized methods should be applied

Evaluation of Allergen-Specific IgE Levels in Students' Sera

Atmospheric fungal spores play important role in allergic reactions in atopic individuals. Monitorization of those spores found in the environment of atopic cases is crucial for the choice of the antigens that will be included in allergen screening procedures and precautions to be taken against mold-originated health problems. Since most of the people spend plenty of time indoors in recent years, the effects of exposure to indoor air fungi on human health have gained importance. This study was aimed to investigate the indoor air mold distribution of elementary schools in Denizli province (located in west Anatolia, Turkey) and to compare the allergen-specific IgE levels of children against the most frequently detected mold genus. A questionnaire (MM080) was distributed to the 4967 students (6-8 year-old) attending first and second degrees of 16 different elementary schools with scattered locations in city center. This questionnaire form included the questions related to the general information about the child, school environment, allergic complaints since last year, home environment and nutrition. Response rate to the questionnaire was 51.6% (2565/4967). Air samples were collected from 18 classrooms in March 2009, during which high rates of allergic symptoms were observed according to the questionnaire results. Mold fungi belonging to 10 different genera (Penicillium spp. 46%; Aspergillus spp. 18%; Cladosporium spp. 17%; Alternaria spp. 15%; Drechslera spp. 1%; Chtysosporium, Fusarium, Conidiobolus and Cladothecium species 0.5%; unidentified 1%) were isolated from indoor air of classrooms. Since the most frequently detected mold was Penicillium spp. (46%), the 48 children with atopic symptoms were called to the hospital for the determination of total IgE and Penicillium specific IgE in their sera. Twenty two students accepted the invitation and serum total IgE (Immulite 2000; Diagnostic Product Corporation, USA) and allergen-specific IgE (Penicillium brevicompactum, Penicillium camemberti, Penicillium chrysogenum, Penicillium commune, Penicillium expansum, Penicillium frequentans, Penicillium glaucum, Penicillium notatum, Penicillium roqueforti ve Penicillium viridicatum) (RIDASCREEN; R-Biopharm AG, Germany) levels were determined in those children. Total IgE levels above reference ranges were detected in 41% (9/22) of the screened sera samples. P.roqueforti, P.commune and P.camemberti antibodies were higher (Odds ratio as 5.50, 4.0 and 3.75, respectively) in sera with high total IgE levels. No independent variables were determined between individual and/or environmental factors and Penicillium-specific IgE antibodies. It was concluded that those three strains should be chosen as antigens for mold allergy screening tests which will be performed among atopic cases in our region. In conclusion it should be kept in mind that molds have a possible role in the development of allergic symptoms, however, they are not the sole determining factor in this process. In the investigation of the allergic diseases environmental factors should be considered and standardized methods should be applied