1,321 research outputs found

    ¿Cuáles son los factores bióticos y abióticos más efectivos que afectan a la composición de ácidos grasos de la Garra rufa (Heckel, 1843)?

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    Specimens of Garra rufa were collected from a warm river and a cool stream in the Bingöl Province, Turkey, once a month over a period of one year. The effects of month, season, gender and location on the fatty acid composition in the muscle and the lipid content were investigated and dietary marker fatty acids were used to obtain dietary preferences in different locations (Ilıcalar, Garip) and periods. Total lipid change was seasonally significant (ANOSIM-R=0.49) at both locations and 18:1ω9, 20:5ω3 and 20:6ω3 were the most abundant dietary fatty acids. Although G. rufa are predominantly herbivores, they can also feed omnivorously on mixed diets depending on the presence and absence of their primary diet. The effect of season was significant on fatty acid composition, regardless of the location (Pperm=0.001). Significant seasonal changes in all the fatty acid compositions could be attributed to seasonal changes in the abundance and diversity of dietary sources in the environment due to the effect of temperature.Se recolectaron especímenes de Garra rufa (pez doctor) de un río cálido y un arroyo frío en la provincia de Bingöl, Turquía, mensualmente durante un año. Se investigaron los efectos del mes, la estación, el género y la ubicación en la composición de ácidos grasos musculares y el contenido de lípidos y se utilizaron los ácidos grasos como marcadores dietéticos para obtener preferencias dietéticas en diferentes lugares (Ilıcalar, Garip) y períodos. El cambio total de lípidos fue estacionalmente significativo (ANOSIM-R=0,49) en ambos lugares y 18:1ω9, 20:5ω3 y 20:6ω3 fueron los ácidos grasos dietéticos más abundantes. Aunque G. rufa son predominantemente herbívoros, también pueden alimentarse de forma omnívora con dietas mixtas según la presencia o ausencia de la dieta principal. El efecto de las estaciones fue significativo en la composición de ácidos grasos independientemente de las localizaciones (Pperm=0.001). Los cambios estacionales significativos en todas las composiciones de ácidos grasos podrían atribuirse a los cambios en la abundancia y diversidad de las fuentes dietéticas en el medio ambiente debido al efecto de la temperatura

    Faithful qubit distribution assisted by one additional qubit against collective noise

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    We propose a distribution scheme of polarization states of a single photon over collective-noise channel. By adding one extra photon with a fixed polarization, we can protect the state against collective noise via a parity-check measurement and post-selection. While the scheme succeeds only probabilistically, it is simpler and more flexible than the schemes utilizing decoherence-free subspace. An application to BB84 protocol through collective noise channel, which is robust to the Trojan horse attack, is also given.Comment: 4 pages, 3 figures; published version in Phys. Rev. Let

    Exact metric around a wiggly cosmic string

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    The exact metric around a wiggly cosmic string is found by modifying the energy momentum-tensor of a straight infinitely thin cosmic string to include an electric current along the symmetry axis.Comment: 5 page

    An elementary optical gate for expanding entanglement web

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    We introduce an elementary optical gate for expanding polarization entangled W states, in which every pair of photons are entangled alike. The gate is composed of a pair of 50:50 beamsplitters and ancillary photons in the two-photon Fock state. By seeding one of the photons in an nn-photon W state into this gate, we obtain an (n+2)(n+2)-photon W state after post-selection. This gate gives a better efficiency and a simpler implementation than previous proposals for W\rm W-state preparation.Comment: 5 pages, 2 figures. To appear in Phys. Rev.

    Experimental ancilla-assisted qubit transmission against correlated noise using quantum parity checking

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    We report the experimental demonstration of a transmission scheme of photonic qubits over unstabilized optical fibers, which has the plug-and-play feature as well as the ability to transmit any state of a qubit, regardless of whether it is known, unknown, or entangled to other systems. A high fidelity to the noiseless quantum channel was achieved by adding an ancilla photon after the signal photon within the correlation time of the fiber noise and by performing quantum parity checking. Simplicity, maintenance-free feature and robustness against path-length mismatches among the nodes make our scheme suitable for multi-user quantum communication networks.Comment: 8 pages, 4 figures; published in New J. Phys. and selected in IOP Selec

    Teleportation of qubit states through dissipative channels: Conditions for surpassing the no-cloning limit

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    We investigate quantum teleportation through dissipative channels and calculate teleportation fidelity as a function of damping rates. It is found that the average fidelity of teleportation and the range of states to be teleported depend on the type and rate of the damping in the channel. Using the fully entangled fraction, we derive two bounds on the damping rates of the channels: one is to beat the classical limit and the second is to guarantee the non-existence of any other copy with better fidelity. Effect of the initially distributed maximally entangled state on the process is presented; and the concurrence and the fully entangled fraction of the shared states are discussed. We intend to show that prior information on the dissipative channel and the range of qubit states to be teleported is helpful for the evaluation of the success of teleportation, where success is defined as surpassing the fidelity limit imposed by the fidelity of 1-to-2 optimal cloning machine for the specific range of qubits.Comment: 12 pages, 7 figures, to appear in Phys. Rev.

    Peroxidase-like activity of hemoglobin-based hybrid materials against different substrates and their enhanced application for H2O2 detection

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    ABSTRACT. Organic-inorganic hybrid nanoflowers method with unique properties are preferred than conventional immobilization methods for the past decade. Hereemoglobin-based hybrid material (HbNFs@Cu) was synthesized under different experimental conditions (pH 5.0-9.0 and 0.01-0.50 mgmL-1 of hemoglobin) obtaining a material size of 9-10 µm. The encapsulation percentage and weight yield of HbNFs@Cu were determined as 100% and 6.7%, respectively. The peroxidase-like activities of the material against different substrates (ABTS and Guaiacol) were compared to free hemoglobin. The HbNFs@Cu hybrid structure exhibited Vmax of 3.6995 EU/mg and a Michaelis-Menten constant (KM) of 0.1357 mM/mL. The HbNFs@Cu hybrid material was then used to catalyze the oxidation of a peroxidase substrate ABTS to the pigmented product, which provided a colorimetric and spectrophotometric detection of H2O2. The linear operating range, detectable colorimetrically as H2O2 sensor, is 0.005-0.0042 mM, while the linear operating range, detectable spectrometically, is 0.003-0.0042 mM. The limits of detection of colorimetric and spectrophotometric sensors were 0.005 mM and 0.003 mM, respectively. Collectively, these results showed that HbNFs@Cu can be used as colorimetric biosensor for H2O2 in potential applications such as pharmaceutical food, biomedical, environmental, and industrial.                     KEY WORDS: Hydrogen peroxide, Hemoglobin, Hybrid Material, Colorimetric assay   Bull. Chem. Soc. Ethiop. 2021, 35(3), 537-550.  DOI: https://dx.doi.org/10.4314/bcse.v35i3.

    Pulse-mode quantum projection synthesis: Effects of mode mismatch on optical state truncation and preparation

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    Quantum projection synthesis can be used for phase-probability-distribution measurement, optical-state truncation and preparation. The method relies on interfering optical lights, which is a major challenge in experiments performed by pulsed light sources. In the pulsed regime, the time frequency overlap of the interfering lights plays a crucial role on the efficiency of the method when they have different mode structures. In this paper, the pulsed mode projection synthesis is developed, the mode structure of interfering lights are characterized and the effect of this overlap (or mode match) on the fidelity of optical-state truncation and preparation is investigated. By introducing the positive-operator-valued measure (POVM) for the detection events in the scheme, the effect of mode mismatch between the photon-counting detectors and the incident lights are also presented.Comment: 11 pages, 4 figures, submitted to Phys. Rev.

    Spinning cosmic strings: a general class of solutions

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    In this work, we give a general class of solutions of the spinning cosmic string in Einstein's theory of gravity. After treating same problem in Einstein Cartan (EC) theory of gravity, the exact solution satisfying both exterior and interior space-times representing a spin fluid moving along the symmetry axis is presented in the EC theory. The existence of closed timelike curves in this spacetime are also examined

    The prevalence of asthma and allergy among university freshmen in Eskisehir, Turkey

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    AbstractThe aim of this study was to determine the current and cumulative prevalence of asthma, allergic rhinitis, atopic dermatitis and reactivities to allergen skin prick tests (SPT) among university freshmen.The data at the first stage were collated through the application of the European Community Respiratory Health Survey (-ECRHS- Stage I) questionnaire on 1603 students registering at various faculties and vocational colleges of Osmangazi University in Eskisehir, Turkey, in the academic year 1997–1998. At the second stage a physical examination as well as allergen SPTs were conducted on 151 students.Of the students within the study group, six (0·4%) had experienced an asthma attack within the previous 12 months, 11 (0·7%) had a past of asthma attacks and 123 (8·1%) reported wheezing attacks within the previous 12 months. The prevalence of asthma-like symptoms, rhinoconjunctivitis and dermatitis were found to be 17·0%, 10·0% and 5·9% respectively. Asthma and asthma-like symptoms were found to be significantly more prevalent among students who smoked. A positive SPT reaction to more than one allergen was found in 14·6% of the students. SPT positivity was 8·3% in asymptomatic students, 27·3% in asthmatic students, 14·5% in those with asthma-like symptoms, 28% in those with non-infectious rhinitis and 7·1% in those with dermatitis. In analysis of logistic regression, a history of atopy, as ascertained in the questionnaire, was seen to have a significant effect on SPT positivity.The rate of self-reported asthma and/or asthma-like symptoms among newly enrolled freshmen at the Osmangazi University was found to be lower than in other countries. Cigarette smoking was seen to increase such symptoms significantly, in comparison to non-smokers
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