1,751 research outputs found

    Large deviations for random walk in a random environment

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    In this work, we study the large deviation properties of random walk in a random environment on Zd\mathbb{Z}^d with d1d\geq1. We start with the quenched case, take the point of view of the particle, and prove the large deviation principle (LDP) for the pair empirical measure of the environment Markov chain. By an appropriate contraction, we deduce the quenched LDP for the mean velocity of the particle and obtain a variational formula for the corresponding rate function IqI_q. We propose an Ansatz for the minimizer of this formula. This Ansatz is easily verified when d=1d=1. In his 2003 paper, Varadhan proves the averaged LDP for the mean velocity and gives a variational formula for the corresponding rate function IaI_a. Under the non-nestling assumption (resp. Kalikow's condition), we show that IaI_a is strictly convex and analytic on a non-empty open set A\mathcal{A}, and that the true velocity ξo\xi_o is an element (resp. in the closure) of A\mathcal{A}. We then identify the minimizer of Varadhan's variational formula at any ξA\xi\in\mathcal{A}. For walks in high dimension, we believe that IaI_a and IqI_q agree on a set with non-empty interior. We prove this for space-time walks when the dimension is at least 3+1. In the latter case, we show that the cheapest way to condition the asymptotic mean velocity of the particle to be equal to any ξ\xi close to ξo\xi_o is to tilt the transition kernel of the environment Markov chain via a Doob hh-transform.Comment: 82 pages. PhD thesis. Advisor: S.R.S. Varadha

    Single production of excited electrons at future e^-e^+, ep and pp colliders

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    We analyzed the potential of the LC with s=0.5\sqrt{s}=0.5 TeV, LC×\timesLHC based ep collider with s=3.74\sqrt{s}=3.74 TeV and LHC with s=14\sqrt{s}=14 TeV to search for excited electrons through transition magnetic type couplings with gauge bosons. The eeγe^{\star}\to e\gamma signal and corresponding backgrounds are studied in detail.Comment: 11 pages, 11 figures, 3 table

    Quantum-dot-spin single-photon interface

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    Using background-free detection of spin-state-dependent resonance fluorescence from a single-electron charged quantum dot with an efficiency of 0:1%, we realize a single spin-photon interface where the detection of a scattered photon with 300 picosecond time resolution projects the quantum dot spin to a definite spin eigenstate with fidelity exceeding 99%. The bunching of resonantly scattered photons reveals information about electron spin dynamics. High-fidelity fast spin-state initialization heralded by a single photon enables the realization of quantum information processing tasks such as non-deterministic distant spin entanglement. Given that we could suppress the measurement back-action to well below the natural spin-flip rate, realization of a quantum non-demolition measurement of a single spin could be achieved by increasing the fluorescence collection efficiency by a factor exceeding 20 using a photonic nanostructure

    Breeding properties of Tinca tinca (L., 1758) living in Kapulukaya Reservoir (Kirikkale, Turkey)

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    This study involves the investigation of Tinca tinca (L., 1758) living in Kapulukaya Reservoir in Turkey. It was observed that the fish reach sexual maturity at the age of III and the breeding period starts in May and ends in July. The mean monthly gonadosomatic indices varied from 1.38 ±0.06 (in October) to 8.01±1.03 (in May). According to monthly variations of the GSI, spawning of the tench takes place between May (8.01 ± 1.03) and June (5.50 ± 0.57). The average egg number per fish was estimated to be 23403 ± 17047 . The eggs diameters varied from 0.50 mm to 1.33 mm (mean 0.86 mm). The relations between the fecundity (F) and body length (L) and body weight (W) were found as F = 0.037799 × L 1.0212 (r = 0.70) and F = 0. 00000175 × W 2.8696 (r = 0.62)

    Aceite de semilla de cardo mariano prensado en frío: propiedades físico-químicas, composición y análisis sensorial

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    Cold pressed oil was produced from milk thistle seeds, and its composition and sensorial properties were determined. The seeds were found to contain 14.98% oil, 17.31% protein and 4.14% ash. The peroxide value of the oil (11.39 meqO2/kg oil) was within acceptable limits according to codex, but the free fatty acidity value (3.45%) exceeded the limit. The oil melted at -20.18 °C and crystallized at -3.71 °C. Linoleic acid (51.97%), β-sitosterol (67.56 mg/100 g oil) and γ-tocopherol (53.60 mg/kg oil) were determined as the main components, respectively. Six sensory descriptive terms (sweet, spicy, raw vegetable, straw, roasted and throat-catching) were described for the oil. Consumer tests proved that cold-pressed milk thistle seed oil had intermediate acceptance scores and consumer satisfaction was moderate. In conclusion, it is thought that milk thistle seeds could be used for the production of edible gourmet oil. Further studies regarding the composition of the bio-active molecules in the oil are anticipated.Se obtuvo aceite prensado en frío a partir de semillas de cardo mariano y se determinó su composición y propiedades sensoriales. Se encontró que las semillas contenían 14,98% de aceite, 17,31% de proteína y 4,14% de ceniza. El índice de peróxido del aceite (11,39 meqO2/kg de aceite) se encontraba dentro del límite aceptable según el Codex, pero el índice de acidez libre (3,45 %) excedía el límite. El aceite fundió a -20,18°C y cristalizó a -3,71°C. Se determinaron como componentes principales el ácido linoleico (51,97%), β-sitosterol (67,56 mg/100 g de aceite) y γ-tocoferol (53,60 mg/kg de aceite), respectivamente. Se describieron en el aceite seis términos descriptivos sensoriales: dulce, picante, vegetal crudo, pajizo, asado y pegajoso. Las pruebas de consumo demostraron que el aceite de semilla de cardo mariano prensado en frío tenía puntuaciones de aceptación intermedias y la satisfacción del consumidor era moderada. En conclusión, se cree que las semillas de cardo mariano podrían utilizarse para la producción de aceite gourmet comestible. Se requieren más estudios sobre la composición de moléculas bioactivas del aceite

    Caracterización integral de las propiedades fisicoquímicas, térmicas, composicionales y sensoriales del aceite de semilla de rosa mosqueta prensado en frío

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    In this study, cold-pressed rosehip seed oil was fully characterized. Acidity and oxidation levels were near the limit values or slightly exceeded them and improvement in the storage conditions was suggested. The oil started to crystallize at -45.25 °C, and melt at -25.56 °C. Linoleic acid (51.1%), β-sitosterol (84.6%), γ-tocopherol (773.76 µg/g) and rosmarinic acid (31.38 µg/g) were determined as major fatty acid, sterol, tocopherol and phenolic compound, respectively. For the first time, aromatic volatile compounds and sensory descriptive terms were determined for cold-pressed rosehip seed oil. Sixty-seven volatile compounds were detected and L-limonene was found to be a major volatile compound. According to the sensory analysis, timber/kindling and raw vegetable tastes/aromas were found to be relatively dominant. Consequently, it is thought that rosehip seeds can be used as a raw material for edible and nutritionally-rich cold-pressed oil production and/or as source oil for functional food preparations.En este estudio se caracterizó completamente el aceite de semilla de rosa mosqueta prensado en frío. Los niveles de acidez y oxidación estaban cerca de los valores límite o los excedían ligeramente y se sugirió mejorar las condiciones de almacenamiento. El aceite comenzó a cristalizar a -45,25°C y a fundirse a -25,56°C. Se determinó el ácido linoleico (51,1%), β-sitosterol (84,6%), γ-tocoferol (773,76 µg/g) y ácido rosmarínico (31,38 µg/g) como principal ácido graso, esterol, tocoferol y compuesto fenólico, respectivamente. Por primera vez, se determinaron compuestos aromáticos volátiles y términos descriptivos sensoriales para el aceite de semilla de rosa mosqueta prensado en frío. Se detectaron sesenta y siete compuestos volátiles y se descubrió que el L-limoneno era un compuesto volátil importante. Según el análisis sensorial, se encontró que los sabores/aromas de madera/astillas y vegetales crudos eran relativamente dominantes. En consecuencia, se cree que las semillas de rosa mosqueta pueden usarse como materia prima para la producción de aceite prensado en frío comestible y nutritivo y/o como aceite fuente para preparaciones de alimentos funcionales

    World raw hide and skin exports and some microbiological problems during

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    Nowadays the biggest countries that produce raw hides are China, India, Brazil and the USA; and major tanning companies are in Argentina, Brazil, China, India, Italy, South Korea, Mexico, Pakistan, Russia, Spain, Turkey and the USA. The top exporter of raw hides and skins is the USA. During exportation many microbes especially bacteria and archaea can damage the raw hides and skins. In this study, some information is given about some microbiological problems during exportation of raw hides and skins
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