Spurious signals in DQF spectroscopy: two-shot stimulated echoes

The most widely used technique for double-quantum filtered (DQF) single-voxel spectroscopy (SVS) is based on a symmetric PRESS sequence with two additional spatially unselective π/2 pulses, one of which is usually frequency selective. The actual filtering, rejecting signals from all uncoupled resonances, can be done by suitable phase cycling of the rf pulses in successive shots, but in practice gradient filtering is always used. Under usual conditions the sequence repetition time is comparable to the spin-lattice relaxation time, and a stimulated echo is formed by five out of the ten rf pulses in two consecutive shots. This echo is not filtered out by the gradients, and additional phase cycling is needed to eliminate it. Its spatial origin is the full transverse slice selected by the last pulse of the PRESS sequence. The SVS shimming procedure may create an important field variation in this slice (outside the volume of interest VOI). Water singlet signals therefore appear in a band of frequencies other than 4.7 ppm, and remain unaffected by water suppression pulses. In practice phase-alternation schemes can reduce these spurious signals by several orders of magnitude, but even then they may mask the weak metabolite signals of interest. We describe a strategy to minimize these spurious signals and propose a 16-step phase cycling scheme that attenuates the stimulated echo in every two-step subcycl

Does (in)formal learning enhance employability?

Not much is known about the actual contribution of informal learning to employability over and above formal learning activities. This paper presents the findings of a research project among 215 university non-academic staff members. Findings indicate that employability is enhanced by a mix of formal and informal learning opportunities. Possibilities for networking appear to be significant for employability

The performance of the K10, K6 and GHQ-12 to screen for present state DSM-IV disorders among disability claimants

BACKGROUND: Screening for mental disorders among disability claimants is important, since mental disorders seem to be seriously under-recognized in this population. However, performance of potentially suitable scales is unknown. We aimed to evaluate the psychometric properties of three scales, the 10- and 6-item Kessler Psychological Distress Scale (K10, K6) and the 12-item General Health Questionnaire (GHQ-12), to predict present state mental disorders, classified according to the Diagnostic and Statistical Manual of Mental Disorders, 4(th)Edition (DSM-IV) among disability claimants. METHODS: All scales were completed by a representative sample of persons claiming disability benefit after two years sickness absence (n=293). All diagnoses, both somatic and mental, were included. The gold standard was the Composite International Diagnostic Interview (CIDI 3.0) to diagnose present state DSM-IV disorder. Cronbach’s α, sensitivity, specificity, positive (PPV) and negative predictive values (NPV), and the areas under the Receiver Operating Characteristic curve (AUC) were calculated. RESULTS: Cronbach’s alpha’s were 0.919 (K10), 0.882 (K6) and 0.906 (GHQ-12). The optimal cut-off scores were 24 (K10), 14 ( K6) and 20 (GHQ-12). The PPV and the NPV for the optimal cut point of the K10 was 0.53 and 0.89, for the K6 0.51 and 0.87, and for the GHQ-12 0.50 and 0.82. The AUC’s for 30-day cases were 0.806 (K10; 95% CI 0.749-0.862), 0.796 (K6; 95% CI 0.737-0.854) and 0.695 (GHQ-12; 95% CI 0.626-0.765). CONCLUSIONS: The K10 and K6 are reliable and valid scales to screen for present state DSM-IV mental disorder. The optimal cut-off scores are 24 (K10) and 14 (K6). The GHQ-12 (optimal cut-off score: 20) is outperformed by the K10 and K6, which are to be preferred above the GHQ-12. The scores on separate items of the K10 and K6 can be used in disability assessment settings as an agenda for an in-depth follow-up clinical interview to ascertain the presence of present state mental disorder

Rituximab administration in third trimester of pregnancy suppresses neonatal B-cell development

We describe the effect on the neonate of administration of rituximab to a woman with idiopathic thrombocytopenic purpura (ITP). Rituximab, an anti-CD20 antibody, was given weekly for 4 weeks to a woman with ITP in her third trimester of pregnancy. One month after the last rituximab administration a healthy girl was born. She had normal growth and development during the first six months. At birth, B-lymphocytes were not detectable. Rituximab levels in mother and neonate were 24000 and 6700 ng/mL, respectively. Only 7 cases of rituximab administration during pregnancy were described. No adverse events are described for fetus and neonate. We demonstrate that rituximab passes the placenta and inhibits neonatal B-lymphocyte development. However, after 6 months B-lymphocyte levels normalized and vaccination titres after 10 months were adequate. No infection-related complications occurred. Rituximab administration during pregnancy appears to be safe for the child but further studies are warranted. Copyright © 2008 D. T. Klink et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. 1

EPR study of vanadium (4+) in the anatase and rutile phases of TiO2

We present cw and pulsed EPR experiments on V4+ in the rutile and anatase phases of TiO2. For the rutile phase, the cw data confirm earlier results, but the relaxation data are different from those previously reported. No earlier results for V4+ in the unreduced pure anatase phase exist. We show that a simple point-charge model can be used to interpret the values of the g tensors, but that models considering only nearest neighbors will give erroneous results. We conclude that the observed V4+ is substitutional in the rutile, but interstitial in the anatase phase. We propose a relaxation mechanism through phonon-modulated hyperfine coupling to explain our T1 data in the rutile phase

Families with pediatric type 1 diabetes : a comparison with the general population on child well-being, parental distress, and parenting behavior

Aims The aim of this study was to compare families with a child (2-12 years) with type 1 diabetes (T1D) to families which are not confronted with chronic illness, with regard to children's well-being, parental distress, and parenting behavior. In addition, differences were explored between families whose child has optimal vs suboptimal glycemic control. Methods Mothers, fathers, and children of 105 families with pediatric T1D completed questionnaires assessing child well-being, parental distress, and parenting. The control group consisted of 414 families without chronic illness. Results With regard to child well-being, children with T1D had more adjustment difficulties (as reported by mothers) and lower quality of life (QoL) (as reported by mothers and fathers), whereas children themselves (8-12 years) reported higher QoL compared to controls. In terms of parental distress, mothers, but not fathers, of children with T1D reported more stress, anxiety symptoms, and depressive symptoms than controls. With regard to parenting behavior, parent reports revealed less protectiveness in fathers and less autonomy support and responsiveness in both parents as compared to controls. No differences were found in parent-reported psychological control between parents of children with and without T1D, but children with T1D perceived lowered parental psychological control. Lastly, secondary analyses indicated that especially families with suboptimal child glycemic control showed more maternal distress and worse child well-being (according to parents). Conclusions Families confronted with pediatric T1D differ from families without chronic illness: childhood T1D impacts parental perceptions of child well-being and differentially affects mothers' and fathers' distress levels and behaviors

Point-Form Analysis of Elastic Deuteron Form Factors

Point-form relativistic quantum mechanics is applied to elastic electron-deuteron scattering. The deuteron is modeled using relativistic interactions that are scattering-equivalent to the nonrelativistic Argonne $v_{18}$ and Reid '93 interactions. A point-form spectator approximation (PFSA) is introduced to define a conserved covariant current in terms of single-nucleon form factors. The PFSA is shown to provide an accurate description of data up to momentum transfers of 0.5 ${\rm GeV}^2$, but falls below the data at higher momentum transfers. Results are sensitive to the nucleon form factor parameterization chosen, particularly to the neutron electric form factor.Comment: RevTex, 31 pages, 1 table, 13 figure