Extended Superscaling of Electron Scattering from Nuclei

An extended study of scaling of the first and second kinds for inclusive electron scattering from nuclei is presented. Emphasis is placed on the transverse response in the kinematic region lying above the quasielastic peak. In particular, for the region in which electroproduction of resonances is expected to be important, approximate scaling of the second kind is observed and the modest breaking of it is shown probably to be due to the role played by an inelastic version of the usual scaling variable.Comment: LaTeX, 36 pages including 5 color postscript figures and 4 postscript figure

Healthcare-associated outbreak of meticillin-resistant Staphylococcus aureus bacteraemia: role of a cryptic variant of an epidemic clone

BACKGROUND New strains of meticillin-resistant Staphylococcus aureus (MRSA) may be associated with changes in rates of disease or clinical presentation. Conventional typing techniques may not detect new clonal variants that underlie changes in epidemiology or clinical phenotype. AIM To investigate the role of clonal variants of MRSA in an outbreak of MRSA bacteraemia at a hospital in England. METHODS Bacteraemia isolates of the major UK lineages (EMRSA-15 and -16) from before and after the outbreak were analysed by whole-genome sequencing in the context of epidemiological and clinical data. For comparison, EMRSA-15 and -16 isolates from another hospital in England were sequenced. A clonal variant of EMRSA-16 was identified at the outbreak hospital and a molecular signature test designed to distinguish variant isolates among further EMRSA-16 strains. FINDINGS By whole-genome sequencing, EMRSA-16 isolates during the outbreak showed strikingly low genetic diversity (P < 1 × 10(-6), Monte Carlo test), compared with EMRSA-15 and EMRSA-16 isolates from before the outbreak or the comparator hospital, demonstrating the emergence of a clonal variant. The variant was indistinguishable from the ancestral strain by conventional typing. This clonal variant accounted for 64/72 (89%) of EMRSA-16 bacteraemia isolates at the outbreak hospital from 2006. CONCLUSIONS Evolutionary changes in epidemic MRSA strains not detected by conventional typing may be associated with changes in disease epidemiology. Rapid and affordable technologies for whole-genome sequencing are becoming available with the potential to identify and track the emergence of variants of highly clonal organisms

Louse (Insecta : Phthiraptera) mitochondrial 12S rRNA secondary structure is highly variable

Lice are ectoparasitic insects hosted by birds and mammals. Mitochondrial 12S rRNA sequences obtained from lice show considerable length variation and are very difficult to align. We show that the louse 12S rRNA domain III secondary structure displays considerable variation compared to other insects, in both the shape and number of stems and loops. Phylogenetic trees constructed from tree edit distances between louse 12S rRNA structures do not closely resemble trees constructed from sequence data, suggesting that at least some of this structural variation has arisen independently in different louse lineages. Taken together with previous work on mitochondrial gene order and elevated rates of substitution in louse mitochondrial sequences, the structural variation in louse 12S rRNA confirms the highly distinctive nature of molecular evolution in these insects

Molecular alterations in dog pheochromocytomas and paragangliomas

Recently, genetic alterations in the genes encoding succinate dehydrogenase subunit B and D (SDHB and SDHD) were identified in pet dogs that presented with spontaneously arising pheochromocytomas (PCC) and paragangliomas (PGL; together PPGL), suggesting dogs might be an interesting comparative model for the study of human PPGL. To study whether canine PPGL resembled human PPGL, we investigated a series of 50 canine PPGLs by immunohistochemistry to determine the expression of synaptophysin (SYP), tyrosine hydroxylase (TH) and succinate dehydrogenase subunit A (SDHA) and B (SDHB). In parallel, 25 canine PPGLs were screened for mutations in SDHB and SDHD by Sanger sequencing. To detect large chromosomal alterations, single nucleotide polymorphism (SNP) arrays were performed for 11 PPGLs, including cases for which fresh frozen tissue was available. The immunohistochemical markers stained positive in the majority of canine PPGLs. Genetic screening of the canine tumors revealed the previously described variants in four cases; SDHB p.Arg38Gln (n = 1) and SDHD p.Lys122Arg (n = 3). Furthermore, the SNP arrays revealed large chromosomal alterations of which the loss of chromosome 5, partly homologous to human chromosome 1p and chromosome 11, was the most frequent finding (100% of the six cases with chromosomal alterations). In conclusion, canine and human PPGLs show similar genomic alterations, suggestive of common interspecies PPGL-related pathways

Superscaling of Inclusive Electron Scattering from Nuclei

We investigate the degree to which the concept of superscaling, initially developed within the framework of the relativistic Fermi gas model, applies to inclusive electron scattering from nuclei. We find that data obtained from the low energy loss side of the quasielastic peak exhibit the superscaling property, i.e., the scaling functions f(\psi') are not only independent of momentum transfer (the usual type of scaling: scaling of the first kind), but coincide for A \geq 4 when plotted versus a dimensionless scaling variable \psi' (scaling of the second kind). We use this behavior to study as yet poorly understood properties of the inclusive response at large electron energy loss.Comment: 33 pages, 12 color EPS figures, LaTeX2e using BoxedEPSF macros; email to [email protected]

Classical Evolution of Quantum Elliptic States

The hydrogen atom in weak external fields is a very accurate model for the multiphoton excitation of ultrastable high angular momentum Rydberg states, a process which classical mechanics describes with astonishing precision. In this paper we show that the simplest treatment of the intramanifold dynamics of a hydrogenic electron in external fields is based on the elliptic states of the hydrogen atom, i.e., the coherent states of SO(4), which is the dynamical symmetry group of the Kepler problem. Moreover, we also show that classical perturbation theory yields the {\it exact} evolution in time of these quantum states, and so we explain the surprising match between purely classical perturbative calculations and experiments. Finally, as a first application, we propose a fast method for the excitation of circular states; these are ultrastable hydrogenic eigenstates which have maximum total angular momentum and also maximum projection of the angular momentum along a fixed direction. %Comment: 8 Pages, 2 Figures. Accepted for publication in Phys. Rev.

Learning L2 collocations incidentally from reading

Previous studies have shown that intentional learning through explicit instruction is effective for the acquisition of collocations in a second language (L2) (e.g. Peters, 2014, 2015), but relatively little is known about the effectiveness of incidental approaches for the acquisition of L2 collocations. The present study examined the incidental acquisition of collocational knowledge when learners encounter adjective-pseudoword collocations while reading. Forty-one L2 learners read a story containing six target collocations in a classroom setting. One week after the reading they were interviewed about their knowledge of the form, meaning and collocation of the target items (at recall and recognition levels). Participants were randomly assigned to one of two experimental groups, i.e. the 4-repetition group and the 8-repetition group. Results showed that collocational knowledge can be learnt incidentally from reading; that it is learnt at a similar rate to other lexical components such as form and meaning of individual words; and that the frequency manipulation in this study did not seem to have a significant effect on the acquisition of any of the aspects examined

Effects of Cooking in Solutions of Varying pH on the Dietary Fiber Components of Vegetables

To study the effect of pH on dietary fiber components of vegetables, beans, cauliflower, potatoes, peas and corn were cooked in buffers of pH 2, 4, 6, and 10. Water-soluble pectin and hemicellulose, water-insoluble pectin and hemicellulose, cellulose and lignin were quantitated in raw, cooked vegetables and cooking medium. Tenderness and pH of raw and cooked vegetables were determined. Texture varied with cooking medium. Cooked vegetables were most firm at pH 4 and softest at pH 10. Dietary components found in cooking medium reflected these textural changes. Vegetables which showed greater pH effects exhibited greater changes in fiber components.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73821/1/j.1365-2621.1984.tb13237.x.pd

Complex relationships among personality traits, job characteristics, and work behaviors

The aim of the study was to investigate the additive, mediating, and moderating effects of personality traits and job characteristics on work behaviors. Job applicants (N = 161) completed personality questionnaires measuring extraversion, neuroticism, achievement motivation, and experience seeking. One and a half years later, supervisors rated the applicants' job performance, and the job incumbents completed questionnaires about skill variety, autonomy, and feedback, work stress, job satisfaction, work self-efficacy, and propensity to leave. LISREL was used to test 15 hypotheses. Perceived feedback mediated the relationship between achievement motivation and job performance. Extraversion predicted work self-efficacy and job satisfaction. Work stress mediated the relationship between neuroticism and job satisfaction. Job satisfaction and experience seeking were related to propensity to leave. Autonomy, skill variety, and feedback were related to job satisfaction

Refining and regaining skills in fixation/diversification stage performers: The Five-A Model

Technical change is one of many factors underpinning success in elite, fixation/diversification stage performers. Surprisingly, however, there is a dearth of research pertaining to this process or the most efficacious methods used to bring about such a change. In this paper we highlight the emergent processes, yet also the lack in mechanistic comprehension surrounding technical change, addressing issues within the motor control, sport psychology, coaching and choking literature. More importantly, we seek an understanding of how these changes can be made more secure to competitive pressure, and how this can be embedded within the process of technical change. Following this review, we propose The Five-A Model based on successful coaching techniques, psychosocial concomitants, the avoidance of choking and principles of effective behaviour change. Specific mechanisms for each stage are discussed, with a focus on the use of holistic rhythm-based cues as a possible way of internalising changes. Finally, we suggest the need for further research to examine these five stages, to aid a more comprehensive construction of the content and delivery of such a programme within the applied setting