Family studies in acute leukaemia in childhood: a possible association with autoimmune disease.

Medical histories of themselves and their first-degree relatives were obtained from parents of 82 leukaemic children (54 acute lymphoblastic (ALL), 28 acute myeloblastic (AML)) and from control couples matched for age. The possibility of a primary familial immunological abnormality as an aetiological factor in childhood leukaemia was suggested by binding some infections significantly more frequently reported in parents than in controls, but more strongly supported by the finding of a significantly (P less than 0.02) increased prevalence of disorders associated with autoimmunity (but not of other conditions such as peptic ulceration, infective hepatitis, tuberculosis or malignancy) amongst members of ALL families compared to those of controls. Analogy with Down's syndrome and the strain of NZB mice, in which diminished T-cell function is associated with autoimmune disease and lymphoid neoplasia, is discussed. Varicella and herpes zoster occurred respectively in 2 ALL mothers during their pregnancies involving the patients and in none of the other 388 pregnancies here reported. This supports previous evidence that antenatal varicella infections may be of aetiological importance in some cases of ALL

Social fragmentation, deprivation and urbanicity: relation to first-admission rates for psychoses

<i>Declaration</i> <i>of</i> <i>interest</i>: None. <i>Background</i>: Social disorganisation, fragmentation and isolation have long been posited as influencing the rate of psychoses at area level. Measuring such societal constructsis difficult. A census-based index measuring social fragmentation has been proposed. <i>Aims</i>: To investigate the association between first-admission rates for psychosis and area-based measures of social fragmentation, deprivation and urban/rural index. <i>Method</i>: We used indirect standardisation methods and logistic regression models to examine associations of social fragmentation, deprivation and urban/rural categories with first admissions for psychoses in Scotland for the 5-year period 1989–1993. <i>Results</i>: Areas characterised by high social fragmentation had higher first-ever admission rates for psychosis independent of deprivation and urban/rural status. There was a dose–response relationship between social fragmentation category and first-ever admission rates for psychosis. There was no statistically significant interaction between social fragmentation, deprivation and urban/rural index. <i>Conclusions</i>: First-admission rates are strongly associated with measures of social fragmentation, independent of material deprivation and urban/rural category

A Combined Spitzer and Herschel Infrared Study of Gas and Dust in the Circumbinary Disk Orbiting V4046 Sgr

We present results from a spectroscopic Spitzer and Herschel mid-to-far-infrared study of the circumbinary disk orbiting the evolved (age ~12-23 Myr) close binary T Tauri system V4046 Sgr. Spitzer IRS spectra show emission lines of [Ne II], H_2 S(1), CO_2 and HCN, while Herschel PACS and SPIRE spectra reveal emission from [O I], OH, and tentative detections of H_2O and high-J transitions of CO. We measure [Ne III]/[Ne II] < 0.13, which is comparable to other X-ray/EUV luminous T Tauri stars that lack jets. We use the H_2 S(1) line luminosity to estimate the gas mass in the relatively warm surface layers of the inner disk. The presence of [O I] emission suggests that CO, H_2O, and/or OH is being photodissociated, and the lack of [C I] emission suggests any excess C may be locked up in HCN, CN and other organic molecules. Modeling of silicate dust grain emission features in the mid-infrared indicates that the inner disk is composed mainly of large (r~5 um) amorphous pyroxene and olivine grains (~86% by mass) with a relatively large proportion of crystalline silicates. These results are consistent with other lines of evidence indicating that planet building is ongoing in regions of the disk within ~30 AU of the central, close binary.Comment: 33 pages, 9 figures, 3 tables. Accepted for publication in Ap

Die Trittpflanzen-Gemeinschaften in den südlichen Städten der Nordinsel Neuseelands

Between September and November 2003 106 vegetation samples of trampled areas were made in 11 New Zealand cities: Gisborne, Hamilton, Lower Hutt, Masterton, Napier, New Plymouth, Palmerston North, Roturoa, Taupo, Wanganui and Wellington. The table, with 81 species, shows three main groups dependent on substrate: 1, trampled surfaces with gravel, compacted soil and combinations of these; 2, flagstones with gaps for plants; and 3, flagstones without gaps or concrete with few cracks. Most of the species (93 %) are not native to New Zealand. In comparison with phytocoenosis of the European vegetation the samples show affinities with temperate and Mediterranean trampled area associations

Duration-dependent effects of the BDNF Val66Met polymorphism on anodal tDCS induced motor cortex plasticity in older adults: a group and individual perspective

The brain derived neurotrophic factor (BDNF) Val66Met polymorphism and stimulation duration are thought to play an important role in modulating motor cortex plasticity induced by non-invasive brain stimulation (NBS). In the present study we sought to determine whether these factors interact or exert independent effects in older adults. Fifty-four older adults (mean age = 66.85 years) underwent two counterbalanced sessions of 1.5 mA anodal transcranial direct current stimulation (atDCS), applied over left M1 for either 10 min or 20 min. Single pulse transcranial magnetic stimulation (TMS) was used to assess corticospinal excitability (CSE) before and every 5 min for 30 min following atDCS. On a group level, there was an interaction between stimulation duration and BDNF genotype, with Met carriers (n =13) showing greater post-intervention potentiation of CSE compared to Val66Val homozygotes (n = 37) following 20 min (p = 0.002) but not 10 min (p = 0.219) of stimulation. Moreover, Met carriers, but not Val66Val homozygotes, exhibited larger responses to TMS (p = 0.046) after 20 min atDCS, than following 10 min atDCS. On an individual level, two-step cluster analysis revealed a considerable degree of inter-individual variability, with under half of the total sample (42%) showing the expected potentiation of CSE in response to atDCS across both sessions. Intra-individual variability in response to different durations of atDCS was also apparent, with one-third of the total sample (34%) exhibiting LTP-like effects in one session but LTD-like effects in the other session. Both the inter-individual (p = 0.027) and intra-individual (p = 0.04) variability was associated with BDNF genotype.In older adults, the BDNF Val66Met polymorphism along with stimulation duration appears to play a role in modulating tDCS-induced motor cortex plasticity. The results may have implications for the design of NBS protocols for healthy and diseased aged populations

A test procedure to investigate lubricant-surface combinations for high-performance racing transmissions

Compact light weight and dry sump (significantly reduced volume of lubricant) are the desired attributes for high performance racing transmissions, whilst improving upon efficiency and reliability remain paramount objectives. The complex multi-objective nature of this task points to an integrated approach to lubricant-mechanical system optimisation. The extreme operating conditions in racing transmissions, such as contact kinematics and thermal loading present significant tribological challenges. Thin lubricant films in non-Newtonian shear are subjected to mixed thermo-elastohydrodynamic regime of lubrication. Under these conditions boundary active lubricant species often determine the contact tribological performance rather than the bulk rheological properties of the lubricant itself. Therefore, the interaction of lubricant additive package with the contacting solid surfaces is the key to an optimised solution. The paper investigates the lubricant-surface interfacial effect upon frictional characteristics in contact conditions which are representative of gear teeth meshing conditions in high performance transmissions. The study uses pin-on-disc tribometry. As the contact conditions are mainly governed by the formation of surface-adhered tribo-films, their effect upon frictional characteristics is further investigated through use of atomic force microscopy (AFM) in lateral force mode (LFM). A test procedure is presented to benchmark lubricant additive package-surface combinations for improved tribological performance. The investigation takes into account surface material, surface topography and lubricant additive package, all of which affect the tribo-chemical absorption or bonding of a thin film to the contacting surfaces. The test protocol also includes surface chemical spectrometry and Scanning Electron Microscopy (SEM). The presented methodology has not hitherto been reported in literatur