Determination of the beam-spin asymmetry of deuteron photodisintegration in the energy region E-gamma=1.1-2.3 GeV

The beam-spin asymmetry, Sigma, for the reaction gamma d -\u3e pn has been measured using the CEBAF Large Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility (JLab) for six photon-energy bins, between 1.1 and 2.3 GeV, and proton angles in the center-of-mass frame, theta(c.m.), between 25 degrees and 160 degrees. These are the first measurements of beam-spin asymmetries at theta(c.m.) = 90. for photon-beam energies above 1.6 GeV, and the first measurements for angles other than theta(c.m.) = 90 degrees. The angular and energy dependence of Sigma is expected to aid in the development of QCD-based models to understand the mechanisms of deuteron photodisintegration in the transition region between hadronic and partonic degrees of freedom, where both effective field theories and perturbative QCD cannot make reliable predictions

Neutron spectroscopy studies of methanol to hydrocarbons catalysis over ZSM-5

Acknowledgements Johnson Matthey plc and the EPSRC are thanked for postgraduate student support (A.P.H., A.Z.) via the Industrial CASE scheme (EP/P510506/1 and EP/N509176/1 respectively). Johnson Matthey plc is additionally thanked for provision of the ZSM-5 catalyst, plus some characterisation information. The STFC Rutherford Appleton Laboratory is thanked for access to the neutron beam facilities. The UK Catalysis Hub is thanked for resources, support and access to the Research Complex at Harwell which is provided via our membership of the UK Catalysis Hub Consortium and funded by UK Engineering and Physical Sciences Research Council (grants EP/K014706/1, EP/K014668/1, EP/K014854/1, EP/K014714/1 and EP/M013219/1).Peer reviewedPublisher PD

The effect of co-feeding methyl acetate on the H-ZSM5 catalysed methanol-to-hydrocarbons reaction

The reactivity of methanol and methyl acetate mixtures over a HZSM-5 catalyst is studied over a period of 6 h at 350 °C, with small molecular weight olefins and aromatic compounds observed as reaction products. Post-reaction analysis of the catalyst shows the coke content to increase with methyl acetate content. Vibrational spectra (DRIFTS and inelastic neutron scattering, INS) indicate the major hydrocarbon species present in the coked catalysts to be methylated aromatic molecules, with INS spectra indicating a greater degree of methylation in the catalysts used with higher methyl acetate content. The greater extent of deactivation at higher methyl acetate concentrations is tentatively attributed to a diminishment of water in the zeolite cavity, which would otherwise facilitate re-generation of the active sites

The Effect of Co-feeding Methyl Acetate on the H-ZSM5 Catalysed Methanol-to-Hydrocarbons Reaction

Funding Information: Johnson Matthey plc and the EPSRC are thanked for postgraduate student support (A.P.H., A.Z.) via the Industrial CASE scheme (EP/P510506/1). Johnson Matthey plc is additionally thanked for provision of the ZSM-5 catalyst. The Science and Technology Facilities Council is thanked for the provision of neutron beam time (RB1820116, https://doi.org/10.5286/isis.e.97999822 ). The resources and support provided by the UK Catalysis Hub via Membership of the UK Catalysis Hub Consortium and funded by EPSRC (Grants EP/K014706/1, EP/K014668/1, EP/ K014854/1, EP/K014714/1, and EP/M013219/1) are gratefully acknowledged.Peer reviewedPublisher PD

Cost Optimization of Ice Distribution

Two questions regarding minimizing fuel costs while delivering ice along a pre-set route are tackled. The first question is when demand exceeds the load of a single truck, so that a second truck of ice has to be taken to some point of the route for the driver/salesman to continue with that for the rest of the route: Is it better: 1) for the first truck to deliver starting from the costumer nearest to the base, or 2) for the first truck to start the delivery from the last costumer (the most distant from the base)? We show that the second strategy was better for the particular data looked at, and we have the basis of an algorithm for deciding which strategy is the better for a given delivery schedule. The second question concerns how best to modify a regular sales route when an extra delivery has to be made. Again, the basis for an algorithm to decide how to minimize fuel costs is derived

Enlarged Perivascular Spaces are Negatively Associated with Montreal Cognitive Assessment Scores in Older Adults

Emerging evidence suggests that enlarged perivascular spaces (ePVS) may be a clinically significant neuroimaging marker of global cognitive function related to cerebral small vessel disease (cSVD). We tested this possibility by assessing the relationship between ePVS and both a standardized measure of global cognitive function, the Montreal Cognitive Assessment (MoCA), and an established marker of cSVD, white matter hyperintensity volume (WMH) volume. One hundred and eleven community-dwelling older adults (56–86) underwent neuroimaging and MoCA testing. Quantification of region-specific ePVS burden was performed using a previously validated visual rating method and WMH volumes were computed using the standard ADNI pipeline. Separate linear regression models were run with ePVS as a predictor of MoCA scores and whole brain WMH volume. Results indicated a negative association between MoCA scores and both total ePVS counts (P ≤ 0.001) and centrum semiovale ePVS counts (P ≤ 0.001), after controlling for other relevant cSVD variables. Further, WMH volumes were positively associated with total ePVS (P = 0.010), basal ganglia ePVS (P ≤ 0.001), and centrum semiovale ePVS (P = 0.027). Our results suggest that ePVS burden, particularly in the centrum semiovale, may be a clinically significant neuroimaging marker of global cognitive dysfunction related to cSVD

Germline mutations in the oncogene EZH2 cause Weaver syndrome and increased human height.

The biological processes controlling human growth are diverse, complex and poorly understood. Genetic factors are important and human height has been shown to be a highly polygenic trait to which common and rare genetic variation contributes. Weaver syndrome is a human overgrowth condition characterised by tall stature, dysmorphic facial features, learning disability and variable additional features. We performed exome sequencing in four individuals with Weaver syndrome, identifying a mutation in the histone methyltransferase, EZH2, in each case. Sequencing of EZH2 in additional individuals with overgrowth identified a further 15 mutations. The EZH2 mutation spectrum in Weaver syndrome shows considerable overlap with the inactivating somatic EZH2 mutations recently reported in myeloid malignancies. Our data establish EZH2 mutations as the cause of Weaver syndrome and provide further links between histone modifications and regulation of human growth

Model selection for K+ ς- Photoproduction within an isobar model

We utilize an isobar model to investigate the K+ς- photoproduction off a neutron in the resonance region. Except for the Born terms, we include high-spin (spin-3/2 and spin-5/2) nucleon resonances in the consistent formalism together with a few Δ and kaon resonances to achieve an acceptable agreement with data. Interestingly, we reveal that no hyperon resonances are needed to achieve a reasonable description of data. On the other hand the N(1720)3/2+ resonance was found to be very important for correct description of data. The free parameters of the model were fitted to experimental data from the LEPS and CLAS Collaborations on either differential cross sections or photon beam asymmetry. The novel feature of the fitting procedure is the use of a regularization method, the least absolute shrinkage selection operator, and information criteria in order to choose the best fit

Investigation of the dynamics of 1-octene adsorption at 293 K in a ZSM-5 catalyst by inelastic and quasielastic neutron scattering

The properties of 1-octene adsorbed in zeolite ZSM-5 at 293 K are studied by means of inelastic and quasielastic neutron scattering (INS and QENS) in order to investigate interactions relevant to the zeolite solid acid catalysis of fluidised catalytic cracking reactions. The INS spectrum is compared to that recorded for the solid alkene and reveals significant changes of bonding on adsorption at ambient temperatures; the changes are attributed to the oligomerization of the adsorbed 1-octene to form a medium chain n-alkane or n-alkane cation. QENS analysis shows that these oligomers are immobilised within the zeolite pore structure but a temperature-dependant fraction is able to rotate around their long axis within the pore channels

The effects of MTG catalysis on methanol mobility in ZSM-5

The UK Catalysis Hub is thanked for resources and support provided via our membership of the UK Catalysis Hub Consortium and funded by EPSRC (grants EP/I038748/1, EP/I019693/1, EP/K014706/1, EP/K014668/1, EP/K014854/1, EP/ K014714/1 and EP/M013219/1). A. J. O. M. would like to acknowledge the Ramsay Trust for provision of the Ramsay Trust Memorial Fellowship. The STFC Rutherford Appleton Laboratory is thanked for access to neutron beam facilities.Peer reviewedPublisher PD