Spin Structure of the Proton from Polarized Inclusive Deep-Inelastic Muon-Proton Scattering

We have measured the spin-dependent structure function $g_1^p$ in inclusive deep-inelastic scattering of polarized muons off polarized protons, in the kinematic range $0.003 < x < 0.7$ and $1 GeV^2 < Q^2 < 60 GeV^2$. A next-to-leading order QCD analysis is used to evolve the measured $g_1^p(x,Q^2)$ to a fixed $Q^2_0$. The first moment of $g_1^p$ at $Q^2_0 = 10 GeV^2$ is $\Gamma^p = 0.136\pm 0.013(stat.) \pm 0.009(syst.)\pm 0.005(evol.)$. This result is below the prediction of the Ellis-Jaffe sum rule by more than two standard deviations. The singlet axial charge $a_0$ is found to be $0.28 \pm 0.16$. In the Adler-Bardeen factorization scheme, $\Delta g \simeq 2$ is required to bring $\Delta \Sigma$ in agreement with the Quark-Parton Model. A combined analysis of all available proton and deuteron data confirms the Bjorken sum rule.Comment: 33 pages, 22 figures, uses ReVTex and smc.sty. submitted to Physical Review

Large enhancement of deuteron polarization with frequency modulated microwaves

We report a large enhancement of 1.7 in deuteron polarization up to values of 0.6 due to frequency modulation of the polarizing microwaves in a two liters polarized target using the method of dynamic nuclear polarization. This target was used during a deep inelastic polarized muon-deuteron scattering experiment at CERN. Measurements of the electron paramagnetic resonance absorption spectra show that frequency modulation gives rise to additional microwave absorption in the spectral wings. Although these results are not understood theoretically, they may provide a useful testing ground for the deeper understanding of dynamic nuclear polarization.Comment: 10 pages, including the figures coming in uuencoded compressed tar files in poltar.uu, which also brings cernart.sty and crna12.sty files neede

Substance abuse and intimate partner violence: treatment considerations

Given the increased use of marital- and family-based treatments as part of treatment for alcoholism and other drug disorders, providers are increasingly faced with the challenge of addressing intimate partner violence among their patients and their intimate partners. Yet, effective options for clinicians who confront this issue are extremely limited. While the typical response of providers is to refer these cases to some form of batterers' treatment, three fundamental concerns make this strategy problematic: (1) most of the agencies that provide batterers' treatment only accept individuals who are legally mandated to complete their programs; (2) among programs that do accept nonmandated patients, most substance-abusing patients do not accept such referrals or drop out early in the treatment process; and (3) available evidence suggests these programs may not be effective in reducing intimate partner violence. Given these very significant concerns with the current referral approach, coupled with the high incidence of IPV among individuals entering substance abuse treatment, providers need to develop strategies for addressing IPV that can be incorporated and integrated into their base intervention packages

Keeping an eye on noisy movements: On different approaches to perceptual-motor skill research and training

Contemporary theorising on the complementary nature of perception and action in expert performance has led to the emergence of different emphases in studying movement coordination and gaze behaviour. On the one hand, coordination research has examined the role that variability plays in movement control, evidencing that variability facilitates individualised adaptations during both learning and performance. On the other hand, and at odds with this principle, the majority of gaze behaviour studies have tended to average data over participants and trials, proposing the importance of universal 'optimal' gaze patterns in a given task, for all performers, irrespective of stage of learning. In this article, new lines of inquiry are considered with the aim of reconciling these two distinct approaches. The role that inter- and intra-individual variability may play in gaze behaviours is considered, before suggesting directions for future research

Osteochondritis dissecans and Osgood Schlatter disease in a family with Stickler syndrome

<p>Abstract</p> <p>Purpose</p> <p>Stickler syndrome is among the most common autosomal dominant connective tissue disorders but is often unrecognised and therefore not diagnosed by clinicians. Despite much speculation, the cause of osteochondrosis in general and osteochondritis dissecans (OCD) and Osgood Schlatter syndrome (OSS) in particular remain unclear. Etiological understanding is essential. We describe a pair of family subjects presented with OCD and OSS as a symptom complex rather than a diagnosis.</p> <p>Methods</p> <p>Detailed clinical and radiographic examinations were undertaken with emphasis on the role of MRI imaging. Magnetic resonance imaging may allow early prediction of articular lesion healing potential in patients with Stickler syndrome.</p> <p>Results</p> <p>The phenotype of Stickler syndrome can be diverse and therefore misleading. The expectation that the full clinical criteria of any given genetic disorder such as Stickler syndrome will always be present can easily lead to an underestimation of these serious inheritable disorders. We report here two family subjects, a male proband and his aunt (paternal sister), both presented with the major features of Stickler syndrome. Tall stature with marfanoid habitus, astigmatism/congenital vitreous abnormality and submucus cleft palate/cleft uvula, and enlarged painful joints with early onset osteoarthritis. Osteochondritis dissecans (OCD) and Osgood Schlatter syndrome (OSS) were the predominating joint abnormalities.</p> <p>Conclusion</p> <p>We observed that the nature of the articular and physeal abnormalities was consistent with a localised manifestation of a more generalised epiphyseal dysplasia affecting the weight-bearing joints. In these two patients, OCD and OSS appeared to be the predominant pathologic musculoskeletal consequences of an underlying Stickler's syndrome. It is empirical to consider generalised epiphyseal dysplasia as a major underlying causation that might drastically affect the weight-bearing joints.</p

Sensory Experience Differentially Modulates the mRNA Expression of the Polysialyltransferases ST8SiaII and ST8SiaIV in Postnatal Mouse Visual Cortex

Polysialic acid (PSA) is a unique carbohydrate composed of a linear homopolymer of α-2,8 linked sialic acid, and is mainly attached to the fifth immunoglobulin-like domain of the neural cell adhesion molecule (NCAM) in vertebrate neural system. In the brain, PSA is exclusively synthesized by the two polysialyltransferases ST8SiaII (also known as STX) and ST8SiaIV (also known as PST). By modulating adhesive property of NCAM, PSA plays a critical role in several neural development processes such as cell migration, neurite outgrowth, axon pathfinding, synaptogenesis and activity-dependent plasticity. The expression of PSA is temporally and spatially regulated during neural development and a tight regulation of PSA expression is essential to its biological function. In mouse visual cortex, PSA is downregulated following eye opening and its decrease allows the maturation of GABAergic synapses and the opening of the critical period for ocular dominance plasticity. Relatively little is known about how PSA levels are regulated by sensory experience and neuronal activity. Here, we demonstrate that while both ST8SiaII and ST8SiaIV mRNA levels decrease around the time of eye opening in mouse visual cortex, only ST8SiaII mRNA level reduction is regulated by sensory experience. Using an organotypic culture system from mouse visual cortex, we further show that ST8SiaII gene expression is regulated by spiking activity and NMDA-mediated excitation. Further, we show that both ST8SiaII and ST8SiaIV mRNA levels are positively regulated by PKC-mediated signaling. Therefore, sensory experience-dependent ST8SiaII gene expression regulates PSA levels in postnatal visual cortex, thus acting as molecular link between visual activity and PSA expression

Abnormal Distracter Processing in Adults with Attention-Deficit-Hyperactivity Disorder

Background: Subjects with Attention-Deficit Hyperactivity Disorder (ADHD) are overdistractible by stimuli out of the intended focus of attention. This control deficit could be due to primarily reduced attentional capacities or, e. g., to overshooting orienting to unexpected events. Here, we aimed at identifying disease-related abnormalities of novelty processing and, therefore, studied event-related potentials (ERP) to respective stimuli in adult ADHD patients compared to healthy subjects. Methods: Fifteen unmedicated subjects with ADHD and fifteen matched controls engaged in a visual oddball task (OT) under simultaneous EEG recordings. A target stimulus, upon which a motor response was required, and non-target stimuli, which did not demand a specific reaction, were presented in random order. Target and most non-target stimuli were presented repeatedly, but some non-target stimuli occurred only once (‘novels’). These unique stimuli were either ‘relative novels ’ with which a meaning could be associated, or ‘complete novels’, if no association was available. Results: In frontal recordings, a positive component with a peak latency of some 400 ms became maximal after novels. In healthy subjects, this novelty-P3 (or ‘orienting response’) was of higher magnitude after complete than after relative novels, in contrast to the patients with an undifferentially high frontal responsivity. Instead, ADHD patients tended to smaller centro-parietal P3 responses after target signals and, on a behavioural level, responded slower than controls