Longitudinal Target-Spin Asymmetries for Deeply Virtual Compton Scattering

A measurement of the electroproduction of photons off protons in the deeply inelastic regime was performed at Jefferson Lab using a nearly 6 GeV electron beam, a longitudinally polarized proton target, and the CEBAF Large Acceptance Spectrometer. Target-spin asymmetries for e p → e\u27p\u27ɣ events, which arise from the interference of the deeply virtual Compton scattering and the Bethe-Heitler processes, were extracted over the widest kinematics in Q2, xB, t, and ɸ, for 166 four-dimensional bins. In the framework of generalized parton distributions, at leading twist the t dependence of these asymmetries provides insight into the spatial distribution of the axial charge of the proton, which appears to be concentrated in its center. These results also bring important and necessary constraints for the existing parametrizations of chiral-even generalized parton distributions

Suicidal ideation in patients with obstructive sleep apnoea and its relationship with disease severity, sleep-related problems and social support

We aimed to assess the prevalence of suicidal ideation and to examine the relationships between obstructive sleep apnoea severity, sleep-related problems, social support and suicidal ideation in obstructive sleep apnoea patients. We included 149 patients (68% male; mean age, 48.99 +/- 9.57 years) with diagnosed obstructive sleep apnoea (Apnoea-Hypopnoea Index > 5) based on full-night polysomnography. The prevalence of suicidal ideation among obstructive sleep apnoea patients was 20.1 per cent. Structural equation modelling showed that suicidal ideation in obstructive sleep apnoea was strongly related to poor sleep quality and high fatigue levels. No relationship between social support and suicidal ideation in obstructive sleep apnoea patients was found

The whole and its parts : why and how to disentangle plant communities and synusiae in vegetation classification

Most plant communities consist of different structural and ecological subsets, ranging from cryptogams to different tree layers. The completeness and approach with which these subsets are sampled have implications for vegetation classification. Non‐vascular plants are often omitted or sometimes treated separately, referring to their assemblages as “synusiae” (e.g. epiphytes on bark, saxicolous species on rocks). The distinction of complete plant communities (phytocoenoses or holocoenoses) from their parts (synusiae or merocoenoses) is crucial to avoid logical problems and inconsistencies of the resulting classification systems. We here describe theoretical differences between the phytocoenosis as a whole and its parts, and outline consequences of this distinction for practise and terminology in vegetation classification. To implement a clearer separation, we call for modifications of the International Code of Phytosociological Nomenclature and the EuroVegChecklist. We believe that these steps will make vegetation classification systems better applicable and raise the recognition of the importance of non‐vascular plants in the vegetation as well as their interplay with vascular plants

Measurement of Target and Double-Spin Asymmetries for the ep → eπ+(n) Reaction in the Nucleon Resonance Region at Low Q²

We report measurements of target- and double-spin asymmetries for the exclusive channel →e→p → eπ+(n) in the nucleon resonance region at Jefferson Lab using the CEBAF Large Acceptance Spectrometer (CLAS). These asymmetries were extracted from data obtained using a longitudinally polarized NH3 target and a longitudinally polarized electron beam with energies 1.1, 1.3, 2.0, 2.3, and 3.0 GeV. The new results are consistent with previous CLAS publications but are extended to a low Q2 range from 0.0065 to 0.35(GeV/c)2. The Q2 access was made possible by a custom-built Cherenkov detector that allowed the detection of electrons for scattering angles as low as 6°. These results are compared with the unitary isobar models JANR and MAID, the partial-wave analysis prediction from SAID, and the dynamic model DMT. In many kinematic regions our results, in particular results on the target asymmetry, help to constrain the polarization-dependent components of these models

First Measurement of Target And Double Spin Asymmetries for ep → epπ° in the Nucleon Resonance Region Above the Δ (1232)

The exclusive channel polarized proton(polarized e,e\u27 p)π0 was studied in the first and second nucleon resonance regions in the Q2 range from 0.187 to 0.770 GeV2 at Jefferson Lab using the CEBAF Large Acceptance Spectrometer (CLAS). Longitudinal target and beam-target asymmetries were extracted over a large range of center-of-mass angles of the π0 and compared to the unitary isobar model MAID, the dynamic model by Sato and Lee, and the dynamic model DMT. A strong sensitivity to individual models was observed, in particular for the target asymmetry and in the higher invariant mass region. This data set, once included in the global fits of the above models, is expected to place strong constraints on the electrocoupling amplitudes A 1/2 and S 1/2 for the Roper resonance N (1400) P11, and the N(1535)S11 and N(1520)D13 states

Injurious falls and subsequent adverse drug events among elderly - a Swedish population-based matched case-control study

Background: Fall injuries are stressful and painful and they have a range of serious consequences for older people. While there is some clinical evidence of unintentional poisoning by medication following a severe fall injuries, population-based studies on that association are lacking. This is investigated in the current study, in which attention is also paid to different clinical conditions of the injured patients. Methods: We conducted a matched case-control study of Swedish residents 60 years and older from various Swedish population-based registers. Cases defined as adverse drug events (ADE) by unintentional poisoning leading to hospitalization or death were extracted from the National Patient Register (NPR) and the Cause of Death Register from January 2006 to December 2009 (n = 4418). To each case, four controls were matched by sex, age and residential area. Information on injurious falls leading to hospitalization six months prior to the date of hospital admission or death from ADE by unintentional poisoning, and corresponding date for the controls, was extracted from the NPR. Data on clinical conditions, such as dispensed medications, comorbidity and previous fall injuries were also extracted from the Swedish Prescribed Drug Register (SPDR) and NPR. Effect estimates were calculated using conditional logistic regression and presented as odds ratios (OR) and 95% confidence intervals (CI). Results: We found a three-fold increased risk of unintentional poisoning by medication in the six-month period after an injurious fall (OR 3.03; 95% CI, 2.54-3.74), with the most pronounced increase 1-3 weeks immediately after (OR, 7.66; 95% CI, 4.86-12.1). In that time window, from among those hospitalized for a fall (n = 92), those who sustained an unintentional poisoning (n = 60) tended to be in poorer health condition and receive more prescribed medications than those who did not, although this was not statistically significant. Age stratified analyses revealed a higher risk of poisoning among the younger (aged 60-79 years) than older elderly (80+ years). Conclusion: Medication-related poisoning leading to hospitalization or death can be an ADE subsequent to an episode of hospitalization for a fall-related injury. Poisoning is more likely to occur closer to the injurious event and among the younger elderly. It cannot be ruled out that some of those falls are themselves ADE and early signs of greater vulnerability among certain patients

Measurement of the Deuteron Structure Function F₂ in the Resonance Region and Evaluation of its Moments

Inclusive electron scattering off the deuteron has been measured to extract the deuteron structure function F2 with the CEBAF Large Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility. The measurement covers the entire resonance region from the quasielastic peak up to the invariant mass of the final-state hadronic system W similar or equal to 2.7 GeV with four-momentum transfers Q2 from 0.4 to 6 (GeV/c)2. These data are complementary to previous measurements of the proton structure function F2 and cover a similar two-dimensional region of Q2 and Bjorken variable x. Determination of the deuteron F2 over a large x interval including the quasielastic peak as a function of Q2, together with the other world data, permit a direct evaluation of the structure function moments for the first time. By fitting the Q2 evolution of these moments with an OPE-based twist expansion we have obtained a separation of the leading twist and higher twist terms. The observed Q2 behavior of the higher twist contribution suggests a partial cancelation of different higher twists entering into the expansion with opposite signs. This cancelation, found also in the proton moments, is a manifestation of the duality phenomenon in the F2 structure function

Measurement of Direct fₒ(980) Photoproduction on the Proton

We report on the results of the first measurement of exclusive f0(980) meson photoproduction on protons for Eγ = 3.0–3.8  GeV and −t = 0.4–1.0  GeV2 . Data were collected with the CLAS detector at the Thomas Jefferson National Accelerator Facility. The resonance was detected via its decay in the π+π− channel by performing a partial wave analysis of the reaction γp→pπ+π− . Clear evidence of the f0(980) meson was found in the interference between P and S waves at M π+π− ∼1  GeV. The S -wave differential cross section integrated in the mass range of the f0(980) was found to be a factor of about 50 smaller than the cross section for the ρ meson. This is the first time the f0(980) meson has been measured in a photoproduction experiment

Transverse Polarization of Σ+ (1189) in Photoproduction on a Hydrogen Target in CLAS

Experimental results on the Σ+(1189) hyperon transverse polarization in photoproduction on a hydrogen target using the CLAS detector at Jefferson Laboratory are presented. The Σ+(1189) was reconstructed in the exclusive reaction γ+p→K0S+Σ+(1189) via the Σ+→pπ0 decay mode. The K0S was reconstructed in the invariant mass of two oppositely charged pions with the π0 identified in the missing mass of the detected pπ+π− final state. Experimental data were collected in the photon energy range Eγ=1.0 –3.5 GeV (√s range 1.66–2.73 GeV). We observe a large negative polarization of up to 95% . As the mechanism of transverse polarization of hyperons produced in unpolarized photoproduction experiments is still not well understood, these results will help to distinguish between different theoretical models on hyperon production and provide valuable information for the searches of missing baryon resonances