Nonperturbative tests of the renormalization of mixed clover-staggered currents in lattice QCD

The Fermilab Lattice and MILC collaborations have shown in one-loop lattice QCD perturbation theory that the renormalization constants of vector and axial-vector mixed clover-asqtad currents are closely related to the product of those for clover-clover and asqtad-asqtad (local) vector currents. To be useful for future higher precision calculations this relationship must be valid beyond one-loop and very general. We test its validity nonperturbatively using clover and Highly Improved Staggered (HISQ) strange quarks, utilising the absolute normalization of the HISQ temporal axial current. We find that the renormalization of the mixed current differs from the square root of the product of the pure HISQ and pure clover currents by 2−3%. We also compare discretization errors between the clover and HISQ formalisms

Precision tests of the J/psi from full lattice QCD: mass, leptonic width and radiative decay rate to eta_c

We show results from calculations in full lattice QCD of the mass, leptonic width and radiative decay rate to eta_c of the J/psi meson. These provide few % tests of QCD. Another (1.5%) test comes from comparison of time-moments of the vector charmonium correlator with results derived from the experimental values of R(e+e- to hadrons) in the charm region

The Benefits of Early Book Sharing (BEBS) for child cognitive and socio-emotional development in South Africa: study protocol for a randomised controlled trial

Background:Children in Low and Middle-Income Countries (LMICs) are at risk for problems in their cognitive, social and behavioural development. Factors such as a lack of cognitive stimulation, harsh parenting practices, and severe and persistent aggression in early childhood are central to the genesis of these problems. Interventions that target the intersection between early childhood development, parenting, and early violence prevention are required in order to meaningfully address these problems. Methods:We are conducting a randomized controlled trial to evaluate a parenting intervention for caregivers of children between 23-27 months, designed to promote child cognitive and socio-emotional development in Khayelitsha, a low income peri-urban township in South Africa. Families are randomly allocated to book sharing or to a wait-list control group. In the intervention, we train caregivers in supportive book-sharing with young children. Training is carried out in small groups over a period of eight weeks. Data are collected at baseline, post-intervention and at six months post-intervention. In addition to targeting child cognitive development, the intervention aims to improve child socio-emotional functioning. Discussion:The Benefits of Early Book Sharing (BEBS) trial aims to evaluate the impact of an early parenting intervention on several key risk factors for the development of violence, including aspects of parenting and child cognition, prosocial behaviour, aggression, and socio-emotional functioning. The study is being carried out in a LMIC where violence constitutes a major social and health burden. Since the intervention is brief and, with modest levels of training, readily deliverable in LMIC contexts, a demonstration that it is of benefit to both child cognitive and socio-emotional development would be of significance

Towards a practical framework for managing the risks of selecting technology to support independent living

Information and communication technology applications can help increase the independence and quality of life of older people, or people with disabilities who live in their own homes. A risk management framework is proposed to assist in selecting applications that match the needs and wishes of particular individuals. Risk comprises two components: the likelihood of the occurrence of harm and the consequences of that harm. In the home, the social and psychological harms are as important as the physical ones. The importance of the harm (e.g., injury) is conditioned by its consequences (e.g., distress, costly medical treatment). We identify six generic types of harm (including dependency, loneliness, fear and debt) and four generic consequences (including distress and loss of confidence in ability to live independently). The resultant client-centred framework offers a systematic basis for selecting and evaluating technology for independent living

The strange and charm quark contributions to the anomalous magnetic moment of the muon from lattice QCD

AbstractWe describe a new technique (published in [1]) to determine the contribution to the anomalous magnetic moment of the muon coming from the hadronic vacuum polarisation using lattice QCD. Our method uses Padé approximants to reconstruct the Adler function from its derivatives at q2=0. These are obtained simply and accurately from time-moments of the vector current-current correlator at zero spatial momentum. We test the method using strange quark correlators calculated on MILC Collaboration's nf=2+1+1 HISQ ensembles at multiple values of the lattice spacing, multiple volumes and multiple light sea quark masses (including physical pion mass configurations). We find the (connected) contribution to the anomalous moment from the strange quark vacuum polarisation to be aμs=53.41(59)×10−10, and the contribution from charm quarks to be aμc=14.42(39)×10−10−1% accuracy is achieved for the strange quark contribution. The extension of our method to the light quark contribution and to that from the quark-line disconnected diagram is straightforward