579 research outputs found

    Anomalous Defects and Their Quantized Transverse Conductivities

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    Using a description of defects in solids in terms of three-dimensional gravity, we study the propagation of electrons in the background of disclinations and screw dislocations. We study the situations where there are bound states that are effectively localized on the defect and hence can be described in terms of an effective 1+1 dimensional field theory for the low energy excitations. In the case of screw dislocations, we find that these excitations are chiral and can be described by an effective field theory of chiral fermions. Fermions of both chirality occur even for a given direction of the magnetic field. The ``net'' chirality of the system however is not always the same for a given direction of the magnetic field, but changes from one sign of the chirality through zero to the other sign as the Fermi momentum or the magnitude of the magnetic flux is varied. On coupling to an external electromagnetic field, the latter becomes anomalous, and predicts novel conduction properties for these materials.Comment: New material added. ReVTeX , 31 pgs., 4 figs.(uses epsf

    Novel Edge States in Self-Dual Gravity

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    In contrast to the Einstein-Hilbert action, the action for self-dual gravity contains vierbeins. They are eleminated at the level of observables by an SL(2,C)SL(2,\mathbb{C}) gauge condition implied by the action. We argue that despite this condition, new "edge" or superselected state vectors corresponding to maps of the spheres S2S^2_{\infty} at infinity to SL(2,C)SL(2, \mathbb{C}) arise. They are characterised by new quantum numbers and they lead to mixed states. For black holes, they arise both at the horizon and the spatial infinity and may be relevant for the black hole information paradox. Similar comments can be made about the Einstein-Palatini action which uses vierbeins.Comment: 15 pages, reference added, some minor notational changes - no changes in conclusio

    Leprosy of the larynx: A case report

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    Leprosy is an ancient deforming disease caused by Mycobacterium leprae, which is still poorly understood and often feared by the general public and even by some in the health care professions Fortunately, the outlook for patients has dramatically improved over the last three decades with the introduction of multi-drug treatment and management strategies that have somewhat diminished the stigma of this diagnosis. We report a rare case of leprosy of larynx. A 45 year old man presented with complaints cough, dyspnea and hoarseness since many years ago. Because of demonstration of acid fast bacilli in smear of his sputum, the diagnosis of tuberculosis was made and anti tuberculosis treatment was initiated. But he developed fever and his symptoms exacerbated. In examination there was a tender erythematous nodule on right supraclavicular region, loss of eyebrows and lashes and disseminated hyper and hypo pigmented cutaneous lesions on abdomen, thorax, back with normal chest x ray. Laryngoscopy to rule out laryngeal tuberculosis was done and granulomatous lesion was seen. Laryngeal and skin biopsy was performed which numerous acid fast bacilli, macrophages and foamy cells suggestive of lepromatous leprosy were demonstrated in both specimens. Treatment was started on multi bacillary regime of WHO multidrug therapy. In conclusion, this report highlights the importance of systemic involvement in lepromatous leprosy especially when the initial presentation is laryngitis or respiratory symptoms. Laryngeal leprosy may mistaken with tuberculosis laryngitis due to respiratory problems and existence of acid fast bacilli in respiratory secretions. © 2009 Tehran University of Medical Sciences. All rights reserved

    Effect of Rosemary and Sweet Marjoram on three Predacious Mites of the Family Phytoseiidae (Acari: Phytoseiidae)

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    The direct toxicity of two essential oils, Majorana hortensis, Moench and Rosmarinus officinalis L. to adult females of the predacious mites, Amblyseius zaheri Yousef and El-Borolossy, Amblyseius barkeri (Hughes) and Typhlodromus athiasae Porath and Swirski were tested. Rosemary oil was the most toxic to females of A. barkeri and the least to A. zaheri. In contrast,sweet marjoram oil was relatively toxic to T. athiasae and slightly toxic to A. barkeri. Both essential oils,decreased the food consumption rate at the concentration used for A.barkeri and A. zaheri. Females of A. barkeri and A. zaheri suffered a depression in reproduction when treated with 1% of rosemary oil.Both material used seems to be harmless to T. athiasae at 1%

    Minus salt goat skin preservation: Extreme chloride reduction in tannery wastewater

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    Content: Animal skins, a byproduct of the meat industry is the basic raw materials for the tanning industry. Just after flaying, animal skins have to preserve protecting it from microbiological destruction. Globally, sodium chloride is mostly used as popular preserving agents for the animal skins. It preserves the skin by its dehydrating ability. Nevertheless, sodium chloride is cost-effective, available, and easy to apply but the method suffers greatly in terms of environmental context. To reduce the pollution load, especially chloride in soaking operation several works have been carried out to preserve animal skins with various agents. This study is intended to preserve the goat skin with Sphagneticola trilobata leaf paste without sodium chloride for reducing the chloride in the soaking liquor. The plant has antimicrobial activity, widely distributed tropical and subtropical regions. The anticipated preservation method was assessed monitoring different parameters e.g., shrinkage temperature, hair slip, putrefaction, odour, moisture content, extractable nitrogen, and bacterial count on fresh (raw), 1st, 4th, 7th, 14th, 21st and 28th day in comparison to the conventional wet salting method. The physical properties of the processed leathers e.g., tensile strength, percentage of elongation, and ball burst of the crust leathers were fulfilled the required values. The chemical parameters like chloride, total dissolved solids (TDS), biochemical oxygen demand (BOD), and chemical oxygen demand (COD) of soaking liquor were investigated. The proposed preservation method was reduced pollution loads: chloride, TDS, BOD, and COD in soaking operation by 98.04%, 92.9%, 90.2% and 85.5%, respectively. The scanning electron microscope (SEM) photographs of both the present and conventional preservation methods processed crust leathers revealed similar texture and quality to each other. The anticipated preservation method could be a sustainable option to preserve goat skin, which could reduce the pollution loads during leather processing. Take-Away: 1. Sphagneticola trilobata leaf paste preserved goat skin up to 28 days 2. Reduction of chloride and TDS were 98.04% and 92.9% in soaking liquor 3. Lessening of BOD and COD were 90.2% and 85.5% in soaking liquo

    A model of Islamic tourism towards religious motivation and tourist satisfaction in Malaysia

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    Abstract The aim of this chapter is to explore the roles of religious motivation in the relationship between tourists' antecedents and their destination and satisfaction , and to provide some guidelines to aid tourism professionals in developing and implementing the niche strategy of Islamic tourism for the advancement of the tourism industry of a country such as Malaysia. In the Malaysian context, the religious motivation of international Muslim tourists is increasingly active in their minds, which suggests that tourism professionals consider Shariah-compliant tourism to keep long-term customer relationships. Perceived value, destination image, and service quality influence international Muslim tourists to look to this destination for satisfaction . As a moderation role, the more the level of religious motivation varies, the more the effect of moderator yields. In addition, tourism professionals necessarily require understanding relevant Shariah rules, character­ istics of international Muslim tourists , and the context of the Islamic country so that they can design a Shariah-compliant tourism strategy and policy effective for further growth of the tourism industr

    Effect of MWCNT doping on the structural and optical properties of PVC/PVDF polymer blend

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    Thin film samples of pristine polyvinyl chloride (PVC), poly vinyldine fluoride (PVDF) in combination with their blend in addition to samples containing factorial mass fraction of multi wall carbon nano-tubes (MWCNTs) in the dopant level were prepared via routine casting technique using tetrahydrofurane (THF) as a common solvent. X-ray diffraction and transmission electron microscopy (TEM) depict the nano-scale (15-25 nm) of functionalized MWCNTs with no surface damage results from functionalization process.X-ray diffraction (XRD) shows a semi-crystalline nature of PVDF with evidence for more than one phase namely a and b phases. The fraction of b phase was calculated and correlated to the dopant content. FTIR optical absorption spectra revels a preservation of the main vibrational bands before and after addition of MWCNTs in the doping level with a presence of new small band 1151 cm-1 assigned for the interaction and complexation between constituents

    Prey suitability of Tuta absoluta larvae (Lepidoptera: Gelechiidae) for three predatory phytoseiid mites (Acari: Phytoseiidae) under laboratory conditions

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    Tomato crop in the Mediterranean Basin has been recently affected by the exotic pest Tuta absoluta (Meyrick), which is difficult to control due to its high reproduction rate and potential to develop resistance to insecticides. In this paper, the suitability and effectiveness of three predatory phytoseiid mites Cydnoseius negevi (Swirski and Amitai), Neoseiulus barkeri (Hughes) and Amblyseius largoensis (Muma), an indigenous species, were evaluated on larvae of T. absoluta under laboratory conditions. First instar larvae of T. absoluta proved to be possible food source for tested phytoseiid mites under laboratory conditions. Females of C. negevi, A. largoensis and N. barkeri were able to feed and sustain oviposition on unfed, first instar larvae of T. absoluta. A diet of insect larvae provided the shortest oviposition period and adult longevity of C. negevi and A. largoensis, while N. barkeri showed the longest corresponding periods. The total and daily number of insect larvae consumed was significantly higher in N. barkeri than in A. largoensis and C. negevi. Likewise, N. barkeri laid significantly higher number of eggs (23.6 eggs / female) than that deposited by C. negevi and A. largoensis (2.5 and 3.9 eggs / female). The sex ratio of the progeny was female biased and ranged: (females / total=0.62-0.68%) when insect larvae were provided for females of C. negevi, A. largoensis and N. barkeri

    Violation of the Landau-Yang theorem from infrared Lorentz symmetry breaking

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    Lorentz symmetry forbids decays of massive spin-1 particle like the Z0 into two massless photons, a result known as the Landau-Yang theorem. But it is known that infrared effects can break Lorentz invariance. Employing the construction of Mund et al. [1] which incorporated this Lorentz violation, we propose an interaction leading to the decay Z0→ 2γ and study the dependence of the decay on the parameter of this Lorentz violation
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