3,616 research outputs found

    Nucleon and nuclear structure functions with non-perturbative and higher order perturbative QCD effects

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    We have studied the nucleon structure functions FiNEM(x,Q2); i=1,2F_{iN}^{EM} (x,Q^2);~i=1,2, by including contributions due to the higher order perturbative QCD effect up to NNLO and the non-perturbative effects due to the kinematical and dynamical higher twist (HT) effects. The numerical results for FiNEM(x,Q2)F_{iN}^{EM}(x,Q^2) are obtained using Martin, Motylinski, Harland-Lang, Thorne (MMHT) 2014 NLO and NNLO nucleon parton distribution functions (PDFs). The dynamical HT correction has been included following the renormalon approach as well as the phenomenological approach and the kinematical HT effect is incorporated using the works of Schienbein et al. These nucleon structure functions have been used as an input to calculate the nuclear structure functions FiAEM(x,Q2)F_{iA}^{EM} (x,Q^2). In a nucleus, the nuclear corrections arise because of the Fermi motion, binding energy, nucleon correlations, mesonic contribution, shadowing and antishadowing effects. These nuclear corrections are taken into account in the numerical calculations to obtain the nuclear structure functions FiAEM(x,Q2)F_{iA}^{EM} (x,Q^2), for the various nuclear targets like 12C^{12}C, 27Al^{27}Al, 56Fe^{56}Fe, 64Cu^{64}Cu, 118Sn^{118}Sn, 197Au^{197}Au and 208Pb^{208}Pb which are of experimental interest. The effect of isoscalarity correction for nonisoscalar nuclear targets has also been studied. The results for the FiAEM(x,Q2)F_{iA}^{EM} (x,Q^2) are compared with nCTEQ nuclear PDFs parameterization as well as with the experimental results from JLab, SLAC and NMC in the kinematic region of 0.1x0.80.1 \le x \le 0.8 for several nuclei.Comment: arXiv admin note: text overlap with arXiv:1705.0990

    Electromagnetic and Weak Nuclear Structure Functions F1,2(x,Q2)F_{1,2}(x,Q^2) in the Intermediate Region of Q2Q^2

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    We have studied nuclear structure functions F1A(x,Q2)F_{1A}(x,Q^2) and F2A(x,Q2)F_{2A}(x,Q^2) for electromagnetic and weak processes in the region of 1GeV2<Q2<8GeV21 GeV^2 < Q^2 <8 GeV^2. The nuclear medium effects arising due to Fermi motion, binding energy, nucleon correlations, mesonic contributions and shadowing effects are taken into account using a many body field theoretical approach. The calculations are performed in a local density approximation using a relativistic nucleon spectral function. The results are compared with the available experimental data. Implications of nuclear medium effects on the validity of Callan-Gross relation are also discussed.Comment: Published in Journal of the Physical Society of Japan (NuInt-2015

    Revisiting νμ(νˉμ)\nu_\mu(\bar\nu_\mu) and νe(νˉe)\nu_e(\bar\nu_e) Induced Quasielastic Scattering from Nuclei in Sub-GeV Energy Region

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    We present the results of charged current quasielastic(CCQE) scattering cross sections from free as well as bound nucleons like in 12C^{12}C, 16O^{16}O, 40Ar^{40}Ar and 208Pb^{208}Pb nuclear targets in Eν(νˉ)  E_\nu(_{\bar\nu})~\le~ 1 GeV energy region. The results are obtained using local Fermi gas model with and without RPA effect. The differences those may arise in the electron and muon production cross sections due to the different lepton mass, uncertainties in the axial dipole mass MAM_A and pseudoscalar form factor, and due to the inclusion of second class currents have been highlighted for neutrino/antineutrino induced processes.Comment: Published in Journal of the Physical Society of Japan (NuInt-2015

    Longevity and mortality in Kennel Club registered dog breeds in the UK in 2014

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    Abstract Background The domestic dog is one of the most diverse mammalian species, exhibiting wide variations in morphology, behaviour and morbidity across breeds. Therefore, it is not unexpected that breeds should also exhibit variation in mortality and longevity. While shorter longevity per se may not necessarily be a welfare issue, a generally foreshortened lifespan in a breed that is accompanied by a high prevalence of a particular cause of death may reveal potentially serious welfare concerns and highlight scope to improve breed welfare. Survey data gathered directly from owners offer useful insights into canine longevity and mortality that can support the overall evidence base for welfare reforms within breeds. Results Mortality data on 5663 deceased dogs registered with the UK Kennel Club were collected from an owner-based survey. The most commonly reported causes of death were old age (13.8%), unspecified cancer (8.7%) and heart failure (4.9%); with 5.1% of deaths reported as unknown cause. Overall median age at death was 10.33 years (interquartile range: 7.17–12.83 years). Breeds varied widely in median longevity overall from the West Highland Terrier (12.71 years) to the Dobermann Pinscher (7.67 years). There was also wide variation in the prevalence of some common causes of death among breeds, and in median longevity across the causes of death. Conclusion Substantial variation in the median lifespan and the prominent causes of death exists across breeds. This study has identified some breeds with both a low median lifespan and also a high proportional mortality for one or more specific causes of death that should be considered as both potential welfare concerns as well as opportunities for improvement

    Large-scale survey to estimate the prevalence of disorders for 192 Kennel Club registered breeds

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    Abstract Background Pedigree or purebred dogs are often stated to have high prevalence of disorders which are commonly assumed to be a consequence of inbreeding and selection for exaggerated features. However, few studies empirically report and rank the prevalence of disorders across breeds although such data are of critical importance in the prioritisation of multiple health concerns, and to provide a baseline against which to explore changes over time. This paper reports an owner survey that gathered disorder information on Kennel Club registered pedigree dogs, regardless of whether these disorders received veterinary care. This study aimed to determine the prevalence of disorders among pedigree dogs overall and, where possible, determine any variation among breeds. Results This study included morbidity data on 43,005 live dogs registered with the Kennel Club. Just under two thirds of live dogs had no reported diseases/conditions. The most prevalent diseases/conditions overall were lipoma (4.3%; 95% confidence interval 4.13-4.52%), skin (cutaneous) cyst (3.1%; 2.94-3.27%) and hypersensitivity (allergic) skin disorder (2.7%; 2.52-2.82%). For the most common disorders in the most represented breeds, 90 significant differences between the within breed prevalence and the overall prevalence are reported. Conclusion The results from this study have added vital epidemiological data on disorders in UK dogs. It is anticipated that these results will contribute to the forthcoming Breed Health & Conservation Plans, a Kennel Club initiative aiming to assist in the identification and prioritisation of breeding selection objectives for health and provide advice to breeders/owners regarding steps that may be taken to minimise the risk of the disease/disorders. Future breed-specific studies are recommended to report more precise prevalence estimates within more breeds

    Pakistani physicians and the repatriation equation

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    In Pakistan, students who are accepted into medical school are congratulated — only half-jokingly — on three counts: that they will become doctors, that they will become certified by the American Board of Medical Specialties, and that they will soon be living in the United States

    Complexes of Some Group(IV) Metal Halides with 5-Aminoindazole

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    The synthesis and characterisation of Sn(IV) halides, Ge(IV), Ti(IV) and Zr(IV) chloride complexes of the type MX4 : Li_ 2 with 5-aminoindazole has been made. The possible structure of these complexes has been proposed on the basis of elemental analysis and infrared spectroscopy. The IR spectra suggest unidentate behaviour of the ligand involving pyrrole nitrogen in all the cases except the tin(IV) bromide complex, where the ligand exhibits its bidentate nature, involving the pyridyl nitrogen. An octahedral geometry has been proposed for all the complexes. In the case of MX4 :\u27L type complexes, except for SnBr4 : L, an octahedral halogen bridged structure has been proposed
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