844 research outputs found

    Constraining study of circular orbits and accretion disk around nonlinear electrodynamics black hole

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    The very latest observation of M87M87 supermassive black hole (BH) by the Event Horizon Telescope (EHT) provides the accretion onto BHs is an interesting study in the theory of gravity. We study the geodesics structure and accretion near a nonlinear electrodynamics BH in strong and weak field approximations. These approximations provide the disc-like structure under the geodesic motion and accretion around the BH. Near the equatorial plane, we provide some new reasons to make circular orbits and accretion of test particles around the BH. Then we investigate perturbations, the critical speed of the fluid and the mass accretion rate of particles around the central object. The physical validity of this study shows that the parameter β\beta and QQ play an important role in the circular orbits and the mass accretion rate in strong and weak field approximations.Comment: 21 pages, 12 figure

    Randomized placebo-controlled trial comparing desloratadine and montelukast in monotherapy and desloratadine plus montelukast in combined therapy for chronic idiopathic urticaria

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    BACKGROUND: H 1 -receptor antagonists are considered to be particularly effective in reducing pruritus, and they are therefore recommended as first-line treatment in patients with chronic idiopathic urticaria (CIU). Recently, antileukotriene receptors have been used in patients with CIU, either administered as monotherapy or combined with H 1 -receptor antagonists. OBJECTIVE: We compared the clinical efficacy of 5 mg of desloratadine administered once daily either as monotherapy or combined with a leukotriene antagonist, 10 mg of montelukast daily, and 10 mg of montelukast administered daily as monotherapy for the treatment of patients affected by CIU with placebo. METHODS: One hundred sixty patients aged 18 to 69 years (mean +/- SD, 43.9 +/- 13.4 years) with a history of moderate CIU were selected. A randomized, double-blind, double-dummy, placebo-controlled, parallel-group study design was used. Patients were treated with 5 mg of desloratadine once daily (n = 40), 10 mg of montelukast once daily (n = 40), 5 mg of desloratadine (n = 40) in the morning plus montelukast in the evening, or matched placebo (n = 40). Assessment of treatment efficacy was based on scores of daily cutaneous symptoms evaluated reflectively and instantaneously. RESULTS: Only the group treated with desloratadine as monotherapy or as combined therapy concluded the whole study. Twenty-seven of the 40 patients in the montelukast group and 35 of the 40 patients in the placebo group discontinued the treatment. As reflective evaluation, all groups showed significant differences compared with the placebo group in terms of total symptom score, number of hives, and size of largest hive. In addition to the pruritus, only the groups treated with desloratadine as monotherapy or combined therapy showed significant differences compared with those receiving placebo, whereas there were no differences between the montelukast and placebo groups. Finally, no differences were found between the desloratadine group and the desloratadine plus montelukast group. The instantaneous evaluation demonstrated similar results regarding the desloratadine group and the desloratadine plus montelukast group versus the placebo group, whereas there were no significant differences between the group treated with montelukast alone and the placebo group for pruritus and size of largest hive. No differences were found between the group treated with desloratadine alone and the desloratadine plus montelukast group. CONCLUSIONS: The results of this comparative study demonstrate that desloratadine is highly effective for the treatment of patients affected by CIU. In addition, the regular combined therapy of desloratadine plus montelukast does not seem to offer a substantial advantage with respect to desloratadine as monotherapy in patients affected by moderate CIU

    Water extract of Cryphaea heteromalla (Hedw.) D. Mohr bryophyte as a natural powerful source of biologically active compounds

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    Bryophytes comprise of the mosses, liverworts, and hornworts. Cryphaea heteromalla, (Hedw.) D. Mohr, is a non-vascular lower plant belonging to mosses group. To the date, the most chemically characterized species belong to the liverworts, while only 3.2% and 8.8% of the species belonging to the mosses and hornworts, respectively, have been investigated. In this work, we present Folin–Ciocalteu and oxygen radical absorbance capacity (ORAC) data related to crude extracts of C. heteromalla obtained by three different extraction solvents: pure water (WT), methanol:water (80:20 v/v) (MET), and ethanol:water (80:20 v/v) (ETH). The water extract proved to be the best solvent showing the highest content of biophenols and the highest ORAC value. The C. heteromalla-WT extract was investigated by HPLC-TOF/MS (High Performance Liquid Chromatography-Time of Flight/Mass Spectrometry) allowing for the detection of 14 compounds, five of which were phenolic compounds, derivatives of benzoic, caffeic, and coumaric acids. Moreover, the C. heteromalla WT extract showed a protective effect against reactive oxygen species (ROS) generation induced by tert-butyl hydroperoxide (TBH) on the murine NIH-3T3 fibroblast cell line

    Randomized placebo-controlled trial comparing fluticasone aqueous nasal spray in mono-therapy, fluticasone plus cetirizine, fluticasone plus montelukast and cetirizine plus montelukast for seasonal allergic rhinitis

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    BACKGROUND: Corticosteroids are considered to be particularly effective in reducing nasal congestion and are therefore recommended as first-line treatment in allergic rhinitis patients with moderate to severe and/or persistent symptoms. OBJECTIVE: We compared the clinical efficacy of fluticasone propionate aqueous nasal spray (FPANS) 200 microg given once daily, administered in mono-therapy or combined therapy with a H1 receptor antagonist (cetirizine, CTZ) or with a leukotriene antagonist (montelukast, MSK), and the combined therapy of CTZ plus MSK in the treatment of patients affected by allergic rhinitis to Parietaria during natural pollen exposure. In addition, we examined the effect of the treatment on eosinophil counts and eosinophil cationic protein (ECP) in nasal lavage performed at beginning of season, during season and at the end of the season. METHODS: One hundred patients aged 12-50 years (mean+/-SD 31.8+/-9.6) with a history of moderate to severe Parietaria pollen-induced seasonal allergic rhinitis were selected. A randomized, double-blind, double dummy, placebo (PLA)-controlled, parallel-group study design was used. Patients were treated FPANS 200 microg once daily (n=20) or with FPANS 200 microg once daily, plus CTZ (10 mg) in the morning (n=20), or with FPANS 200 microg once daily, plus MSK (10 mg) in the evening (n=20) or with CTZ (10 mg) in the morning plus MSK in the evening (n=20) or matched PLA (n=20). Assessment of efficacy was based on scores of daily nasal symptoms and on eosinophil counts and ECP in nasal lavage. RESULTS: All treatments showed significant differences (P<0.001) compared with PLA in terms of total symptom, rhinorrhea, sneezing and nasal itching scores. Concerning nasal congestion on waking and daily only the groups treated with FPANS in mono-therapy or in combined therapy showed significant differences compared with PLA. Comparing the group treated with FPANS alone and the groups treated with FPANS plus CTZ, we found significant differences for total symptom score (P=0.04) and for nasal itching (P=0.003). The comparison between FPANS plus CTZ and FPANS plus MSK showed significant difference for nasal itching (P=0.003). Finally, there were significant differences between the group treated with FPANS and the group treated with CTZ plus MSK for total symptom score (P=0.009), for nasal congestion on waking (P<0.001) and nasal congestion daily (P<0.001). Also the comparisons between the group treated with FPANS plus CTZ and the group treated with CTZ plus MSK demonstrated significant differences (P<0.001) for total symptom, for nasal congestion on waking and for nasal congestion on daily, for rhinorrhea (P=0.04) and for nasal itching (P=0.003) scores. Concerning the comparison between the group treated with FPANS plus MSK and the group treated with CTZ plus MSK we found significant differences for total symptom score (P=0.005), for nasal congestion on waking (P<0.001) and for nasal congestion on daily (P<0.001). No other differences were observed between the groups. Concerning blood eosinophil counts, significant differences were found between the treatments with FPANS in mono-therapy or in combined therapy with PLA group during and at the end of the season (P=0.0003 and P<0.0001, respectively). Concerning eosinophils and ECP in nasal lavage, all treatments showed significant differences (P<0.001) compared with PLA. Besides, there were significant differences (P<0.001) between the groups treated with FPANS alone or in combined therapy and the group treated with CTZ plus MSK. CONCLUSION: The results of this comparative study demonstrate that FPANS is highly effective for treating patients affected by allergic rhinitis, with efficacy exceeding that of CTZ plus MSK in combined therapy. In addition, the regular combined therapy of FPANS plus CTZ or plus MSK would not seem to offer substantial advantage with respect to FPANS in mono-therapy in patients affected by seasonal allergic rhinitis

    CZT-Based Harmonic Analysis in Smart Grid Using Low-Cost Electronic Measurement Boards

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    This paper validates the use of a harmonic analysis algorithm on a microcontroller to perform measurements of non-stationary signals in the context of smart grids. The increasing presence of electronic devices such as inverters of distributed generators (DG), power converters of charging stations for electric vehicles, etc. can drain non-stationary currents during their operation. A classical fast Fourier transform (FFT) algorithm may not have sufficient spectral resolution for the evaluation of harmonics and inter-harmonics. Thus, in this paper, the implementation of a chirp-Z transform (CZT) algorithm is suggested, which has a spectral resolution independent from the observation window. The CZT is implemented on a low-cost commercial microcontroller, and the absolute error is evaluated with respect to the same algorithm implemented in the LabVIEW environment. The results of the tests show that the CZT implementation on a low-cost microcontroller allows for accurate measurement results, demonstrating the feasibility of reliable harmonic analysis measurements even in non-stationary conditions on smart grids

    Identification of Epigenetic Signature Associated With Alpha Thalassemia/Mental Retardation X-linked Syndrome

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    BACKGROUND: Alpha thalassemia/mental retardation X-linked syndrome (ATR-X) is caused by a mutation at the chromatin regulator gene RESULTS: We performed genome-wide DNA methylation assessment of the peripheral blood samples from 18 patients with ATR-X and compared it to 210 controls. We demonstrated the evidence of a unique and highly specific DNA methylation epi-signature in the peripheral blood of ATRX patients, which was corroborated by targeted bisulfite sequencing experiments. Although genomically represented, differentially methylated regions showed evidence of preferential clustering in pericentromeric and telometric chromosomal regions, areas where ATRX has multiple functions related to maintenance of heterochromatin and genomic integrity. CONCLUSION: Most significant methylation changes in the 14 genomic loci provide a unique epigenetic signature for this syndrome that may be used as a highly sensitive and specific diagnostic biomarker to support the diagnosis of ATR-X, particularly in patients with phenotypic complexity and in patients wit

    A comparative study of Tam3 and Ac transposition in transgenic tobacco and petunia plants

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    Transposition of the Anthirrinum majus Tam3 element and the Zea mays Ac element has been monitored in petunia and tobacco plants. Plant vectors were constructed with the transposable elements cloned into the leader sequence of a marker gene. Agrobacterium tumefaciens-mediated leaf disc transformation was used to introduce the transposable element constructs into plant cells. In transgenic plants, excision of the transposable element restores gene expression and results in a clearly distinguishable phenotype. Based on restored expression of the hygromycin phosphotransferase II (HPTII) gene, we established that Tam3 excises in 30% of the transformed petunia plants and in 60% of the transformed tobacco plants. Ac excises from the HPTII gene with comparable frequencies (30%) in both plant species. When the β-glucuronidase (GUS) gene was used to detect transposition of Tam3, a significantly lower excision frequency (13%) was found in both plant species. It could be shown that deletion of parts of the transposable elements Tam3 and Ac, removing either one of the terminal inverted repeats (TIR) or part of the presumptive transposase coding region, abolished the excision from the marker genes. This demonstrates that excision of the transposable element Tam3 in heterologous plant species, as documented for the autonomous element Ac, also depends on both properties. Southern blot hybridization shows the expected excision pattern and the reintegration of Tam3 and Ac elements into the genome of tobacco plants.

    Commissioning Status of the Fritz Haber Institute THz FEL

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    The THz Free-Electron Laser (FEL) at the Fritz Haber Institute (FHI) of the Max Planck Society in Berlin is designed to deliver radiation from 3 to 300 microns using a single-plane-focusing mid-IR undulator and a two-plane-focusing far-IR undulator that acts as a waveguide for the optical mode. A key aspect of the accelerator performance is the low longitudinal emittance, < 50 keV-psec, that is specified to be delivered at 200 pC bunch charge and 50 MeV from a gridded thermionic electron source. We utilize twin accelerating structures separated by a chicane to deliver the required performance over the < 20 - 50 MeV energy range. The first structure operates at near fixed field while the second structure controls the output energy, which, under some conditions, requires running in a decelerating mode. "First Light" is targeted for the centennial of the sponsor in October 2011 and we will describe progress in the commissioning of this device to achieve this goal. Specifically, the measured performance of the accelerated electron beam will be compared to design simulations and the observed matching of the beam to the mid-IR wiggler will be described

    Status of the Fritz Haber Institute THz FEL

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    The THz FEL at the Fritz Haber Institute (FHI) in Berlin is designed to deliver radiation from 4 to 400 microns. A single-plane-focusing undulator combined with a 5.4 m long cavity is used is the mid-IR (< 50 micron), while a two-plane-focusing undulator in combination with a 7.2 m long cavity with a 1-d waveguide for the optical mode is used for the far-IR. A key aspect of the accelerator performance is low longitudinal emittance, < 50 keV-psec, at 200 pC bunch charge and 50 MeV from a gridded thermionic electron source. We utilize twin accelerating structures separated by a chicane to deliver the required performance over the < 20 - 50 MeV energy range. The first structure operates at near fixed field while the second structure controls the output energy, which, under some conditions, requires running in a decelerating mode. "First Light" is targeted for the centennial of the FHI in October 2011 and we will describe progress in the commissioning of this device. Specifically, the measured performance of the accelerated electron beam will be compared to design simulations and the observed matching of the beam to the mid-IR wiggler will be described
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