949 research outputs found

    Scalar Casimir effect between two concentric D-dimensional spheres

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    The Casimir energy for a massless scalar field between the closely spaced two concentric D-dimensional (for D>3) spheres is calculated by using the mode summation with contour integration in the complex plane of eigenfrequencies and the generalized Abel-Plana formula for evenly spaced eigenfrequency at large argument. The sign of the Casimir energy between closely spaced two concentric D-dimensional spheres for a massless scalar field satisfying the Dirichlet boundary conditions is strictly negative. The Casimir energy between D-1 dimensional surfaces close to each other is regarded as interesting both by itself and as the key to describing of stability of the attractive Casimir force. PACS number(s): 03.70.+k, 11.10.Kk, 11.10.Gh, 03.65.GeComment: 14 pages. arXiv admin note: substantial text overlap with arXiv:1207.418

    Determination of Bioactive Compounds and Mineral Contents of Seedless Parts and Seeds of Grapes

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    In this study, phenolic compounds, minerals, total flavonoids, total phenolic contents and antioxidant activities of the seedless parts (pulp+skin) and seeds of table and wine grapes were determined. Also, the total oil, tocopherol contents and fatty acid composition of seed oils of table and wine grapes were investigated. The highest total phenolic content of the grape pulp was found in Trakya ilkeren (199.063mg/100 g), while total flavonoid and antioxidant activity of the pulp was determined at a high level in Red Globe (6.810 mg/g, 90.948%). Antioxidant activity, and the total phenolic and flavonoid contents of grape seeds varied between 86.688 and 90.974%, 421.563 and 490.625 mg GAE/100 g, and 90.595 and 145.595 mg/g respectively (p < 0.05). Generally, the main phenolic compounds of all grape pulps and seeds were gallic acid, 3,4- dihydroxybenzoic acid, (+)-catechin and 1,2-dihydroxybenzene. In addition, the oil contents of grape seeds ranged from 5.275 (Çavuş) to 13.881% (Çınarlı karası) (p < 0.05). The major fatty acids of grape seed oils were linoleic, oleic and palmitic acid. The seed oil of the Trakya ilkeren variety was rich in tocopherols in comparison with the other varieties. The major minerals of both the seedless parts and the seeds were determined as K, Ca, P, S, Mg

    Bioactive Properties, Fatty Acid Composition and Mineral Contents of Grape Seed and Oils

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    The oil content of grape seed samples changed between 4.53% (Adakarası) and 11.13% (Sauvignon blanc). While the linoleic acid contents of grape seed oils ranged from 47.34% (Sangiovese) to 72.91% (Cinsaut), the oleic acid contents varied between 13.35% (Cabernet Sauvignon) and 26.30% (Sangiovese) (p < 0.05). Also, the palmitic acid and stearic acid contents of grape seed oils ranged from 7.15% (Cinsaut) to 16.06% (Sangiovese) and from 2.43% (Narince) to 6.55% (Sangiovese) respectively (p < 0.05). The flavonoid contents of the seeds changed between 263.53 (mg CE/g) and 1 706.00 (mg CE/g) (Cabernet Sauvignon). Total phenols were found to be between 6 711.14 (mg GA/g extract) (Sangiovese) and 8 818.69 (mg GA/g extract) (Narince). The linoleic contents of oils changed from between 47.34% (Sangiovese) and 72.91% (Cinsaut). The K contents of the grape seed samples changed between 4 347.80 mg/kg (Cabernet Sauvignon) and 9 492.60 mg/kg (Gamay) (p < 0.05). The Fe contents of seeds were found to be between 29.96 mg/kg (Narince) and 73.82 mg/kg (Sangiovese). As a result, the current study shows that grape seeds are useful for human nutrition due to their components

    Eltrombopag for the treatment of immune thrombocytopenia: The aegean region of Turkey experience

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    Objective: Immune thrombocytopenia (ITP) is an immune-mediated disease characterized by transient or persistent decrease of the platelet count to less than 100x109/L. Although it is included in a benign disease group, bleeding complications may be mortal. With a better understanding of the pathophysiology of the disease, thrombopoietin receptor agonists, which came into use in recent years, seem to be an effective option in the treatment of resistant cases. This study aimed to retrospectively assess the efficacy, long-term safety, and tolerability of eltrombopag in Turkish patients with chronic ITP in the Aegean region of Turkey. Materials and Methods: Retrospective data of 40 patients with refractory ITP who were treated with eltrombopag in the Aegean region were examined and evaluated. Results: The total rate of response was 87%, and the median duration of response defined as the number of the platelets being over 50x109/L was 19.5 (interquartile range: 5-60) days. In one patient, venous sinus thrombosis was observed with no other additional risk factors due to or related to thrombosis. Another patient with complete response and irregular follow-up for 12 months was lost due to sudden death as the result of probable acute myocardial infarction. Conclusion: Although the responses to eltrombopag were satisfactory, patients need to be monitored closely for overshooting platelet counts as well as thromboembolic events. © 2015 Turkish Society of Hematology. All rights reserved

    Wavelength Tunability of Ion-bombardment Induced Ripples on Sapphire

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    A study of ripple formation on sapphire surfaces by 300-2000 eV Ar+ ion bombardment is presented. Surface characterization by in-situ synchrotron grazing incidence small angle x-ray scattering and ex-situ atomic force microscopy is performed in order to study the wavelength of ripples formed on sapphire (0001) surfaces. We find that the wavelength can be varied over a remarkably wide range-nearly two orders of magnitude-by changing the ion incidence angle. Within the linear theory regime, the ion induced viscous flow smoothing mechanism explains the general trends of the ripple wavelength at low temperature and incidence angles larger than 30. In this model, relaxation is confined to a few-nm thick damaged surface layer. The behavior at high temperature suggests relaxation by surface diffusion. However, strong smoothing is inferred from the observed ripple wavelength near normal incidence, which is not consistent with either surface diffusion or viscous flow relaxation.Comment: Revtex4, 19 pages, 10 figures with JPEG forma

    Effect of size and surrounding forest vegetation on chemical properties of soil in forest gaps

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    Short communication: Serranus cabrilla (Linnaeus, 1758) (Perciformes, Serranidae) a new host record for Nerocila orbigyni (Guérin-Mèneville, 1832) (Isopoda, Cymothoidae)

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    Cymothoids are among the largest parasites of fishes in the world. These isopods associate with many commercially important fish species and attach themselves to the body or fins of the fishes. The isopods cause significant economic losses to fisheries by killing, stunting, or damaging these fishes. ... The serranid fish, Serranus cabrilla (Linnaeus, 1758) (the comber) is a commercial species and has a wide distribution (north Atlantic Sea [sic], North Sea and Mediterranean Sea). The comber is a demersal species found on rocks, and on sandy and muddy bottoms at depths of 1-500 [meters]. This is the main species captured by trawlers fishing in the Aegean Sea of the Turkish coast. N. orbignyi has been determined for the first time on S. cabrilla from the Turkish coasts within the frame of the present study

    Clinical performance of direct composite resin versus indirect restorations on endodontically treated posterior teeth:A systematic review and meta-analysis

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    STATEMENT OF PROBLEM: High-level evidence concerning the restoration of endodontically treated posterior teeth by means of direct composite resin or indirect restorations is lacking. PURPOSE: The purpose of this systematic review and meta-analysis was to analyze the current literature on the direct and indirect restoration of endodontically treated posterior teeth. MATERIAL AND METHODS: Databases MEDLINE, CENTRAL, and EMBASE were screened. Risk of bias was assessed by using the ROB2 tool for RCTs and the ROBINS-I tool for prospective and retrospective clinical studies. Randomized clinical trials (RCTs) and prospective and retrospective studies comparing direct composite resin and indirect restorations on endodontically treated posterior teeth were included. Outcomes were tooth and restoration survival. A meta-analysis was conducted for tooth retention and restorative success. RESULTS: Twenty-two studies were included (2 RCTs, 3 prospective, and 17 retrospective). Over the short term (2.5 to 3 years), low-quality evidence suggested no difference in tooth survival. For the prospective and retrospective clinical trials, the overall risk of bias was serious to critical from the risk of confounding because of a difference in restorative indication: Direct restorations were fabricated when one marginal ridge remained or when tooth prognosis was unfavorable. For short-term restorative success, low-quality evidence suggested no difference between the direct and indirect restorations. CONCLUSIONS: For the short term (2.5 to 3 years), low-quality evidence suggests no difference in tooth survival or restoration quality. To assess the influence of the type of restoration on the survival and restorative success of endodontically treated posterior teeth, clinical trials that control for the amount of coronal tooth tissue and other baseline characteristics are needed

    Catching up with Method and Process Practice: An Industry-Informed Baseline for Researchers

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    Software development methods are usually not applied by the book.companies are under pressure to continuously deploy software products that meet market needs and stakeholders\u27 requests. To implement efficient and effective development processes, companies utilize multiple frameworks, methods and practices, and combine these into hybrid methods. A common combination contains a rich management framework to organize and steer projects complemented with a number of smaller practices providing the development teams with tools to complete their tasks. In this paper, based on 732 data points collected through an international survey, we study the software development process use in practice. Our results show that 76.8% of the companies implement hybrid methods.company size as well as the strategy in devising and evolving hybrid methods affect the suitability of the chosen process to reach company or project goals. Our findings show that companies that combine planned improvement programs with process evolution can increase their process\u27 suitability by up to 5%

    Adhesion behavior of conventional and high‐translucent zirconia: Effect of surface conditioning methods and aging using an experimental methodology

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    Objective: Evaluate the adhesive behavior of conventional and high-translucent zirconia after surface conditioning and hydrothermal aging. Materials and methods: Conventional (ZrC) and high-translucent zirconia (ZrT) specimens were divided into six groups: without surface treatment (ZrC and ZrT), air-borne particle abrasion with 50-μm Al2 O3 sized particles (ZrC-AO and ZrT-AO), and tribochemical treatment with 30-μm silica modified Al2 O3 sized particles (ZrC-T and ZrT-T). Zirconia specimens were treated using an MDP-containing universal adhesive and bonded to two resins blocks with an adhesive luting cement. Microbar specimens with cross-sectioned areas of 1 mm2 were achieved. Half of the microbars were subjected to hydrothermal aging. Bond strength was evaluated by microtensile bond strength test and statistically evaluated by the Weibull analysis. Results: Roughness of the ZrC-AO and ZrT-AO groups were statistically higher. Bond strength analysis revealed higher bond strength for ZrC-AO and ZrC-T groups compared to ZrT-AO and ZrT-T, respectively. Mixed failure was the most frequent for the mechanically treated groups, while no cohesive failures were obtained. Conclusion: Lower values of bond strength were obtained for the mechanically treated high-translucent zirconia groups when compared to their conventional zirconia counterparts. Mechanical surface treatment significantly improved the bond strength to conventional and high-translucent zirconia. Clinical significance: Mechanical surface treatment (air-borne particle abrasion or tribochemical treatment) associated with the use of universal adhesives containing MDP could provide a durable bonding to conventional and high-translucent zirconia. Keywords: adhesive cementation; high-translucent zirconia; microtensile bond strength
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