Effectiveness of preoperative planning in the restoration of balance and view in ankylosing spondylitis

Object. The object of this study was to assess the effectiveness of preoperative planning in the restoration of balance and view angle in patients treated with lumbar osteotomy in ankylosing spondylitis (AS). Methods. The authors prospectively analyzed 8 patients with a thoracolumbar kyphotic deformity due to AS that was treated using a closing wedge osteotomy (CWO) of the lumbar spine to correct sagittal imbalance and horizontal view. Preoperative planning to predict postoperative balance, defined by the sagittal vertical axis (SVA) and the sacral endplate angle (SEA), and the view angle, defined by the chin-brow to vertical angle (CBVA), was performed using the ASKyphoptan computational program. Results. All patients were treated with a CWO at level L-4 and improved in balance and view angle. The mean correction angle was 35° (range 24-47°). The postoperative SEA improved from 21 to 36° for a mean correction of 15°. In addition, the SVA and CBVA improved significantly. Note, however, that the postoperative results did not exactly reflect the predicted values of the analyzed parameters. Conclusions. Preoperative planning for the restoration of balance and view angle in AS improves understanding of the biomechanical and clinical effects of a correction osteotomy of the lumbar spine. The adaptation of basic clinical and biomechanical principles to restore balance is advised in such a way that the individual SEA is corrected by 15° (maximum 40°) in relation to the horizon and C-7 is balanced exactly above the posterosuperior corner of the sacrum

Strange-Beauty Meson Production at ppˉp\bar p Colliders

The production rates and transverse momentum distributions of the strange-beauty mesons $B_s$ and $B_s^*$ at $p\bar p$ colliders are calculated assuming fragmentation is the dominant process. Results are given for the Tevatron in the large transverse momentum region, where fragmentation is expected to be most important.Comment: Minor changes in the discussion section. Also available at http://www.ph.utexas.edu/~cheung/paper.htm

On the π\pi and KK as qqˉq \bar q Bound States and Approximate Nambu-Goldstone Bosons

We reconsider the two different facets of $\pi$ and $K$ mesons as $q \bar q$ bound states and approximate Nambu-Goldstone bosons. We address several topics, including masses, mass splittings between $\pi$ and $\rho$ and between $K$ and $K^*$, meson wavefunctions, charge radii, and the $K-\pi$ wavefunction overlap.Comment: 15 pages, late

Di-electron and two-photon widths in charmonium

The vector and pseudoscalar decay constants are calculated in the framework of the Field Correlator Method. Di-electron widths: $\Gamma_{ee}(J/\psi)=5.41$ keV, $\Gamma_{ee}(\psi'(3686))=2.47$ keV, $\Gamma_{ee}(\psi''(3770))=0.248$ keV, in good agreement with experiment, are obtained with the same coupling, $\alpha_s=0.165$, in QCD radiative corrections. We show that the larger $\alpha_s=0.191\pm 0.004$ is needed to reach agreement with experiment for $\Gamma_{\gamma\gamma}(\eta_c)=7.22$ keV, $\Gamma_{\gamma\gamma} (\chi(^3P_0))=3.3$ keV, $\Gamma_{\gamma\gamma}(\chi(^3P_2))= 0.54$ keV, and also for $\Gamma(J/\psi\to 3g)=59.5$ keV, $\Gamma(J/\psi\to \gamma 2g)=5.7$ keV. Meanwhile even larger $\alpha_s=0.238$ gives rise to good description of $\Gamma(\psi'\to 3g)=52.7$ keV, $\Gamma(\psi'\to \gamma 2g)= 3.5$ keV, and provides correct ratio of the branching fractions: $\frac{\mathcal{B}(J/\psi\to light hadrons)}{\mathcal{B}(\psi'\to light hadrons)}=0.24.$Comment: 8 pages, no figure

The decay constants of pseudoscalar mesons in a relativistic quark model

The decay constants of pseudoscalar mesons are calculated in a relativistic quark model which assumes that mesons are made of a valence quark antiquark pair and of an effective vacuum like component. The results are given in terms of quark masses and of some free parameters entering the expression of the internal wave functions of the mesons. By using the pion and kaon decay constants $F_{\pi^+}=130.7~MeV,~F_{K^+}=159.8~MeV$ to fix the parameters of the model one gets $60~MeV\leq F_{D^+}\leq 185~MeV,~95~MeV\leq F_{D_s}\leq230~MeV,~80~MeV\leq F_{B^+}\leq205~MeV$ for the light quark masses $m_u=5.1~MeV,~m_d=9.3~MeV,~m_s=175~MeV$ and the heavy quark masses in the range: $1.~GeV\leq m_c\leq1.6~GeV,~4.1~GeV\leq m_b\leq4.5~GeV$. In the case of light neutral mesons one obtains with the same set of parameters $F_{\pi^0}\approx 138~MeV,~F_\eta\approx~130~MeV,F_{\eta'} \approx~78~MeV$. The values are in agreement with the experimental data and other theoretical results.Comment: 11 pages, LaTe

Adapting group schema therapy for older adults with personality disorders:Lessons learnt

A first empirical study into group schema therapy in older adults with mood disorders and personality disorder (PD) features has shown that brief group schema therapy has potential to decrease psychological distress and to change early maladaptive schemas (EMS). Effect sizes however were smaller than those found in similar studies in younger adults. Therefore, we set out to adapt the treatment protocol for older adults in order to enhance its feasibility and outcome in this age group. We examined this adapted protocol in 29 older adults (mean age 66 years) with PDs from four Dutch mental health institutes. The primary outcome was symptomatic distress, measured by the Brief Symptom Inventory. Secondary outcomes were measured by the Young Schema Questionnaire, the Schema Mode Inventory, and the short version of the Severity Indices of Personality Problems. Contrary to our expectations, the adapted treatment protocol yielded only a small effect size in our primary outcome, and no significant improvement in EMS, modes and personality functioning. Patients pointed out that they were more aware of their dysfunctional patterns, but maybe they had not been able yet to work on behavioural change due to this schema therapy treatment being too brief. We recommend more intensive treatment for older patients with PDs, as they might benefit from more schema therapy sessions, similar to the treatment dosage in younger PD patients. They might also benefit from a combination of group therapy and individual treatment sessions

Leptonic widths of high excitations in heavy quarkonia

Agreement with the measured electronic widths of the $\psi(4040)$, $\psi(4415)$, and $\Upsilon (11019)$ resonances is shown to be reached if two effects are taken into account: a flattening of the confining potential at large distances and a total screening of the gluon-exchange interaction at r\ga 1.2 fm. The leptonic widths of the unobserved $\Upsilon(7S)$ and $\psi(5S)$ resonances: $\Gamma_{e^+e^-}(\Upsilon (7S))=0.11$ keV and $\Gamma(\psi(5S))\approx 0.54$ keV are predicted.Comment: 11 pages revtex

Narratives of Industry Responses to Cyberbullying: Perspectives on Self-regulation From and About the Industry

In this chapter, we provide an overview of narratives about online inter- mediaries’ responses to cyberbullying from the perspectives of policy makers and the companies, as well as children and parents. Relevant self-regulatory and self- organisational efforts are discussed aswell as the rationales for their adoption; includ- ing how the effectiveness of these efforts is seen from the perspectives of various stakeholders. We draw attention to the relative paucity of data on effectiveness of companies’ mechanisms, particularly from the perspective of any benefits received by children as a result of these interventions and support