589 research outputs found

    Food quality and safety situation in Turkey: governance and barriers to success

    Get PDF
    The institutional environment for food quality and safety in Turkey is rapidly changing in the last decade but there are still some inconsistencies compared with the EU. High costs of establishing quality assurance systems (QAS), inefficient capacity of the institutional frame, unknown consumer attitudes, low level of production techniques and lack of awareness of producers and consumers are important weaknesses, when evaluating the current food quality and safety situation in Turkey. Whereas, rapid development of QAS, increase in consumer demands, harmonisation of legislation with the EU, increase in the research and incentives for quality production, and production potentials were determined as strong points. When analysing the socio-economic situation of farms, producers’ knowledge, perception and interest in quality with Rapid Rural Appraisal (RRA), it is found that producers did not accumulate capital because of the low profits, a handicap for expanding and investing into production and product quality. Moreover, the producers' knowledge is limited and their quality perception mainly focuses on food safety. As a result, academic studies and research projects needs to be extended and the adaptation of the Turkish legislation with the EU should be completed accordingly.Food Quality Governance, SMEs Barrier for Food Quality, Food Quality Assurance, Agricultural and Food Policy, Food Consumption/Nutrition/Food Safety,

    Analysis of Jet-Wing Distributed Propulsion from Thick Wing Trailing Edges

    Get PDF
    Conventional airliners use two to four engines in a Cayley-type arrangement to provide thrust, and the thrust is concentrated right behind the engine. Distributed propulsion is the idea of redistributing the thrust across most, or all, of the wingspan of an aircraft. This can be accomplished by using several large engines and using a duct to spread out the exhaust flow to form a jet-wing or by using many small engines spaced along the span of the wing. Jet-wing distributed propulsion was originally suggested as a way to improve propulsive efficiency. A previous study at Virginia Tech assessed the potential gains in propulsive efficiency. The purpose of this study was to assess the performance benefits of jet-wing distributed propulsion. The Reynolds-averaged, finitevolume, Navier-Stokes code GASP was used to perform parametric computational fluid dynamics (CFD) analyses on two-dimensional jet-wing models. The jet-wing was modeled by applying jet boundary conditions on the trailing edges of blunt trailing edge airfoils such that the vehicle was self-propelled. As this work was part of a Blended-Wing-Body (BWB) distributed propulsion multidisciplinary optimization (MDO) study, two airfoils of different thickness were modeled at BWB cruise conditions as examples. One airfoil, representative of an outboard BWB wing section, was 11% thick. The other airfoil, representative of an inboard BWB wing section, was 18% thick. Furthermore, in an attempt to increase the propulsive efficiency, the trailing edge thickness of the 11% thick airfoil was doubled in size. The studies show that jet-wing distributed propulsion can be used to obtain propulsive efficiencies on the order of turbofan engine aircraft. If the trailing edge thickness is expanded, then jet-wing distributed propulsion can give improved propulsive efficiency. However, expanding the trailing edge must be done with care, as there is a drag penalty

    Airframe Noise Modeling Appropriate for Multidisciplinary Design and Optimization

    Get PDF
    A Trailing Edge Noise Metric has been developed for constructing response surfaces that may be used for optimization problems involving aerodynamic noise from a clean wing. The modeling approach includes a modified version of a theoretical trailing edge noise prediction and utilizes a high fidelity CFD (RANS) code with a two-equation turbulence model to obtain the characteristic velocity and length scales used in the noise model. The noise metric is not the absolute value of the noise intensity, but an accurate relative noise measure as shown in the validation studies. Parametric studies were performed to investigate the effect of the wing geometry and the lift coefficient on the noise metric. 2-D parametric studies were done using two subsonic (NACA0012 and NACA0009) and two supercritical (SC(2)-0710 and SC(2)-0714) airfoils. The EET Wing (a generic conventional transport wing) was used for the 3-D study. With NACA 0012 and NACA 0009 airfoils, a reduction in the trailing edge noise was obtained by decreasing the lift coefficient and the thickness ratio, while increasing the chord length to keep the same lift at a constant speed. Supercritical airfoil studies showed that decreasing the thickness ratio may increase the noise at high lift coefficients while a reduction may be obtained at low lift coefficients. Both 2-D and 3-D studies demonstrated that the trailing edge noise remains almost constant at low lift coefficients and gets larger at high lift coefficients. The increase in the noise metric can be dramatic when there is significant flow separation. Three-dimensional effects observed in the EET Wing case indicate the importance of calculating the noise metric with a characteristic velocity and length scale that vary along the span

    Food Quality Assurance Schemes in Turkey

    Get PDF
    In 2008 and 2009, JRC-IPTS cooperated with Akdeniz University (UNIAKD) to analyse food quality assurance schemes in Turkey. The governance structure of food quality assurance in Turkey is explained, which includes public, semi-public and private institutes, laws and legislations, policies and research. Lack of consumer and producer quality awareness is determined as the main problem by SWOT and Logical Framework Matrix (LFM) studies. A Rapid Rural Appraisal (RRA) study was conducted by interviewing local stakeholders. Turkish producers' knowledge is limited and their quality perception focuses mainly on food safety. There are barriers in exports due to quality that reduce the Turkish share in world food markets. The study concludes with several recommendations on how problems in Turkish food quality assurance schemes could be effectively overcome.JRC.DDG.J.5-Agriculture and Life Sciences in the Econom

    Comparison of sirolimus and colchicine treatment on the development of peritoneal fibrozis in rats having peritoneal dialysis

    Get PDF
    Background: Continuous ambulatory peritoneal dialysis is a successful treatment modality for patients with end-stage renal disease. Peritoneal fibrosis (PF) is the most critical complication of long-term peritoneal di- alysis (PD). Aims: In our study, we aimed to compare the effects of colchicine and sirolimus on PF induced by hypertonic peritoneal dialysis solutions in rats. Study Design: Animal experiment. Methods: Twenty-four rats were randomly divided into three groups. The control group received an intraperitoneal injection (ip) of saline. The sirolimus group received the PD solution, plus 1.0 mg/kg/day Rapamune®. The colchicine group received the PD solution ip plus 1.0 mg/kg/day of colchicine. Blood sam- ples were taken to measure the serum levels of VEGF, TGF-β, and TNF-α. Peritoneal tissue samples were taken for histopathological evaluation. Results: TGF-β and TNF-α values in the sirolimus group were found to be statistically significantly lower than in the control and colchicine groups, but the differences between the control and colchicine groups were not statistically significant. No statistically significant differences were found between the groups regarding the VEGF values. Vascular neogenesis and peritoneal thickness were compared; the values in the sirolimus group were statistically reduced compared to the values in the control group. Mild fibrosis developed in 75% of all animals in the sirolimus group; there was no moderate or severe fibrosis observed. Fibrosis developed to varying degrees in 100% of the animals in the control and colchicine groups. Conclusion: The present study demonstrates that sirolimus might be beneficial for preventing or delaying the progression of PF and neoangiogenesis. These alterations in the peritoneal membrane may be connected with reduced TNF-α and TGF-β levels

    Evaluating functional capacity, and mortality effects in the presence of atrial electromechanical conduction delay in patients with systolic heart failure

    Get PDF
    Objective: Atrial functions are relatively suppressed in heart failure (HF). We aimed to investigate the associations of intra- and inter-atrial electromechanical conduction delay (EMCD) with functional class and mortality over a 12-month follow-up period. Methods: The prospective study included 65 patients with systolic HF and 65 healthy subjects with normal sinus rhythm. Left ventricular (LV) systolic functions and left atrial (LA) dimensions and volumes were evaluated by transthoracic echocardiography. Tissue Doppler imaging (TDI) signals at the lateral border of the mitral annulus (lateral PA’), septal mitral annulus (septal PA’), and tricuspid annulus (tricuspid PA’) were measured. Intra- and inter-atrial EMCD were calculated. Results: Mitral inflow velocities were studied using pulsed-wave Doppler after placing the sample volume at the leaflets’ tips. The peak early (E wave) and late (A wave) velocities were measured. The septal annular E/E’ ratio was relatively higher and lateral, septal, and right ventricular S, E’, and A’ waves were significantly lower in the HF group than in the control group (12.49±6.03 - 7.16±1.75, pE/E’ <0.0001). Intra-atrial EMCD was detected as 117.5 ms and inter-atrial EMCD as 127.5 ms in patients with prolonged atrial EMCD. A significant increase was found in prolonged intra- and inter-atrial EMCD according to functional capacity increase (p=0.012 and p=0.031, respectively). The incidence of mortality was significantly higher in patients with prolonged atrial EMCD (p=0.025), and 5 patients in the HF group died during the study over the 12-month follow-up period. Conclusions: In this study, we found a relationship between prolonged atrial conduction time and increased functional class and mortality in patients with systolic HF. © 2016 by Turkish Society of Cardiology

    Performance Evaluation of Silicon Mach-Zehnder Modulator after Cosmic Radiation to Enable Small Satellite Laser Communication

    Get PDF
    To evaluate the performance change of Photonic integrated circuits after real cosmic radiation, silicon Mach-Zehnder Modulators were mounted on International Space Station on Low Earth Orbit for 6 months’ radiation harshness. Measured data of the device before and after radiation showed the permanent change of the effective index (around 10-3), the reduced carrier recombination lifetime, and the extended high speed bandwidth

    Morphological and Biochemical Characteristics of Wild Loquat (Eriobotrya japonica Lindl.) Genotypes in Turkey

    Get PDF
    This study was carried out to determine the pomological and biochemical characteristics of eight different loquat genotypes collected from the Black Sea region (Turkey) in 2018. Totally 20 fruits, at the same ripening stage, were collected from the selected genotypes and tested. Results suggested that there were a high (0.768-0.907) positive and statistically significant correlations among all pomological features (P 0.05). According to the PCA (principal component analysis) analysis of the pomological characteristics, the genotype #1 was superior as compared with other genotypes. Contrary to the pomological characteristics, genotype #1 was found to have the lowest phenolic compounds and it was also moderate in sugar content but a high-grade genotype by organic acids, especially citric acid and malic acid. Furthermore, results suggested that genotypes #3, #4, #7 and #8 were identical and were rich in glucose, succinic acid, and total flavonoid. The results suggested that loquat fruits had a high potential for health benefits. The results are also a preliminary key reference for future studies in terms of loquat cultivation throughout the world and have high potential as a functional food
    corecore