2,960 research outputs found

    A descriptive analysis of child-relevant systematic reviews in the Cochrane Database of Systematic Reviews

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    <p>Abstract</p> <p>Background</p> <p>Systematic reviews (SRs) are considered an important tool for decision-making. There has been no recent comprehensive identification or description of child-relevant SRs. A description of existing child-relevant SRs would help to identify the extent of available child-relevant evidence available in SRs and gaps in the evidence base where SRs are required. The objective of this study was to describe child-relevant SRs from the Cochrane Database of Systematic Reviews (CDSR, Issue 2, 2009).</p> <p>Methods</p> <p>SRs were assessed for relevance using pre-defined criteria. Data were extracted and entered into an electronic form. Univariate analyses were performed to describe the SRs overall and by topic area.</p> <p>Results</p> <p>The search yielded 1666 SRs; 793 met the inclusion criteria. 38% of SRs were last assessed as up-to-date prior to 2007. Corresponding authors were most often from the UK (41%). Most SRs (59%) examined pharmacological interventions. 53% had at least one external source of funding. SRs included a median of 7 studies (IQR 3, 15) and 679 participants (IQR 179, 2833). Of all studies, 48% included only children, and 27% only adults. 94% of studies were published in peer-reviewed journals. Primary outcomes were specified in 72% of SRs. Allocation concealment and the Jadad scale were used in 97% and 25% of SRs, respectively. Adults and children were analyzed separately in 12% of SRs and as a subgroup analysis in 14%. Publication bias was assessed in only 14% of SRs. A meta-analysis was conducted in 68% of SRs with a median of 5 trials (IQR 3, 9) each. Variations in these characteristics were observed across topic areas.</p> <p>Conclusions</p> <p>We described the methodological characteristics and rigour of child-relevant reviews in the CDSR. Many SRs are not up-to-date according to Cochrane criteria. Our study describes variation in conduct and reporting across SRs and reveals clinicians' ability to access child-specific data.</p

    Разработка технологии утилизации отходов птицеводства в кормовую добавку

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    В статье рассматриваются проблемы утилизации перо-пухового сырья птицефабрик в высокобелковые корма и кормовые продукты для сельскохозяйственных животных и птиц. Представлена актуальность и приоритет разработки данного направления в развития нашей страны. Показана рациональность применения перо-пуховых отходов в качестве источника белковых веществ в рационах сельскохозяйственных животных и птиц. Рассмотрена модель структуры главного белка пера - кератина. Предложена технологическая схема производства биопрепарата на основе культур промышленных непатогенных микроорганизмов: Bacillus pumilus SAFR-032, Microbacterium terregens AC1180, Bacillus fastidiosus B11090, Arthrobacter globiformis AC1529, Streptomyces olivocinereus AC1169, Acinetobacter sp. B3905 для утилизации кератинсодержащих отходов, а также технологические этапы производства кормовой добавки из перо-пуховых отходов с применением разработанного биопрепарата.In the annotation the problems of perception of disposing feather-down raw poultry farms in high-protein forage and fodder products for agricultural animals and birds are considered in the article. The urgency and priority of developing this direction in the development of our country is presented. It shows a rational application of down-feather waste as a source of proteins in the diet of farm animals and birds. A model of the structure of the main protein of the pen - keratin is considered. Bioproduct proposed technological production scheme based on industrial crops nonpathogenic microorganisms: Bacillus pumilus SAFR-032, Microbacterium terregens AC1180, Bacillus fastidiosus B11090, Arthrobacter globiformis AC1529, Streptomyces olivocinereus AC1169, Acinetobacter sp. B3905 keratin-waste for recycling, as well as the technological stages of production of the feed additive of the pen-feather waste developed using a biological product

    O(a)-improved quark action on anisotropic lattices and perturbative renormalization of heavy-light currents

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    We investigate the Symanzik improvement of the Wilson quark action on anisotropic lattices. Taking first a general action with nearest-neighbor and clover interactions, we study the mass dependence of the ratio of the hopping parameters, the clover coefficients, and an improvement coefficient for heavy-light vector and axial vector currents. We show how tree-level improvement can be achieved. For a particular choice of the spatial Wilson coupling, the results simplify, and O(m0aτ)O(m_0a_\tau) improvement is possible. (Here m0m_0 is the bare quark mass and aτa_\tau the temporal lattice spacing.) With this choice we calculate the renormalization factors of heavy-light bilinear operators at one-loop order of perturbation theory employing the standard plaquette gauge action.Comment: 26 pages, 8 figure

    Magnetoresistance, specific heat and magnetocaloric effect of equiatomic rare-earth transition-metal magnesium compounds

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    We present a study of the magnetoresistance, the specific heat and the magnetocaloric effect of equiatomic RETRETMg intermetallics with RE=LaRE = {\rm La}, Eu, Gd, Yb and T=AgT = {\rm Ag}, Au and of GdAuIn. Depending on the composition these compounds are paramagnetic (RE=LaRE = {\rm La}, Yb) or they order either ferro- or antiferromagnetically with transition temperatures ranging from about 13 to 81 K. All of them are metallic, but the resistivity varies over 3 orders of magnitude. The magnetic order causes a strong decrease of the resistivity and around the ordering temperature we find pronounced magnetoresistance effects. The magnetic ordering also leads to well-defined anomalies in the specific heat. An analysis of the entropy change leads to the conclusions that generally the magnetic transition can be described by an ordering of localized S=7/2S=7/2 moments arising from the half-filled 4f74f^7 shells of Eu2+^{2+} or Gd3+^{3+}. However, for GdAgMg we find clear evidence for two phase transitions indicating that the magnetic ordering sets in partially below about 125 K and is completed via an almost first-order transition at 39 K. The magnetocaloric effect is weak for the antiferromagnets and rather pronounced for the ferromagnets for low magnetic fields around the zero-field Curie temperature.Comment: 12 pages, 7 figures include

    Scattering and Thermodynamics of Fractionally-Charged Supersymmetric Solitons

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    We show that there are solitons with fractional fermion number in integrable NN=2 supersymmetric models. We obtain the soliton S-matrix for the minimal, NN=2 supersymmetric theory perturbed in the least relevant chiral primary field, the Φ(1,3)\Phi _{(1,3)} superfield. The perturbed theory has a nice Landau-Ginzburg description with a Chebyshev polynomial superpotential. We show that the S-matrix is a tensor product of an associated ordinary ADEADE minimal model S-matrix with a supersymmetric part. We calculate the ground-state energy in these theories and in the analogous NN=1 case and SU(2)SU(2) coset models. In all cases, the ultraviolet limit is in agreement with the conformal field theory.Comment: 27 page

    Exact Conductance through Point Contacts in the ν=1/3\nu =1/3 Fractional Quantum Hall Effect

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    The conductance for tunneling through a point contact between two ν=1/3\nu =1/3 quantum Hall edges is described by a universal scaling function, which has recently been measured experimentally. We compute this universal function exactly, by using the thermodynamic Bethe ansatz and a Boltzmann equation.Comment: 10 pages, 1 figur

    Solving 1d plasmas and 2d boundary problems using Jack polynomials and functional relations

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    The general one-dimensional ``log-sine'' gas is defined by restricting the positive and negative charges of a two-dimensional Coulomb gas to live on a circle. Depending on charge constraints, this problem is equivalent to different boundary field theories. We study the electrically neutral case, which is equivalent to a two-dimensional free boson with an impurity cosine potential. We use two different methods: a perturbative one based on Jack symmetric functions, and a non-perturbative one based on the thermodynamic Bethe ansatz and functional relations. The first method allows us to compute explicitly all coefficients in the virial expansion of the free energy and the experimentally-measurable conductance. Some results for correlation functions are also presented. The second method provides in particular a surprising fluctuation-dissipation relation between the free energy and the conductance.Comment: 19 page

    Radio Bursts Associated with Flare and Ejecta in the 13 July 2004 Event

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    We investigate coronal transients associated with a GOES M6.7 class flare and a coronal mass ejection (CME) on 13 July 2004. During the rising phase of the flare, a filament eruption, loop expansion, a Moreton wave, and an ejecta were observed. An EIT wave was detected later on. The main features in the radio dynamic spectrum were a frequency-drifting continuum and two type II bursts. Our analysis shows that if the first type II burst was formed in the low corona, the burst heights and speed are close to the projected distances and speed of the Moreton wave (a chromospheric shock wave signature). The frequency-drifting radio continuum, starting above 1 GHz, was formed almost two minutes prior to any shock features becoming visible, and a fast-expanding piston (visible as the continuum) could have launched another shock wave. A possible scenario is that a flare blast overtook the earlier transient, and ignited the first type II burst. The second type II burst may have been formed by the same shock, but only if the shock was propagating at a constant speed. This interpretation also requires that the shock-producing regions were located at different parts of the propagating structure, or that the shock was passing through regions with highly different atmospheric densities. This complex event, with a multitude of radio features and transients at other wavelengths, presents evidence for both blast-wave-related and CME-related radio emissions.Comment: 14 pages, 6 figures; Solar Physics Topical Issue, in pres

    Quarkonium correlators and spectral functions at zero and finite temperature

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    We study quarkonium correlators and spectral functions at zero and finite temperature using the anisotropic Fermilab lattice formulation with anisotropy xi=2 and 4. To control cutoff effects we use several different lattice spacings. The spectral functions were extracted from lattice correlators with Maximum Entropy Method based on a new algorithm. We find evidence for the survival of 1S quarkonium states in the deconfined medium till relatively high temperatures as well as for dissolution of 1P quarkonium states right above the deconfinement temperature.Comment: 22 pages, 31 figures, uses revtex styl
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