More on random-lattice fermions

The lattice fermion determinants, in a given background gauge field, are evaluated for two different kinds of random lattices and compared to those of naive and wilson fermions in the continuum limit. While the fermion doubling is confirmed on one kind of lattices, there is positive evidence that it may be absent for the other, at least for vector interactions in two dimensions. Combined with previous studies, arbitrary randomness by itself is shown to be not a sufficient condition to remove the fermion doublers.Comment: 3 pages, uuencoded compress postscript, contributed poster at the Lattice '94 Symposiu

Liprin- 1, ERC1 and LL5 define polarized and dynamic structures that are implicated in cell migration

Cell migration during development and metastatic invasion requires the coordination of actin and adhesion dynamics to promote protrusive activity at the front of the cell. The knowledge of the molecular mechanisms required to achieve such coordination is fragmentary. Here, we identify a new functional complex that drives cell motility. ERC1a (an isoform of ERC1) and the LL5 proteins LL5α and LL5β (encoded by PHLDB1 and PHLDB2, respectively) are required, together with liprin-α1, for effective migration and tumor cell invasion, and do so by stabilizing the protrusive activity at the cell front. Depletion of either protein negatively affects invasion, migration on extracellular matrix, lamellipodial persistence and the internalization of active integrin β1 receptors needed for adhesion turnover at the front of the cell. Liprin-α1, ERC1a and LL5 also define new highly polarized and dynamic cytoplasmic structures uniquely localized near the protruding cell edge. Our results indicate that the functional complex and the associated structures described here represent an important mechanism to drive tumor cell migration

Quarkonium Production at High-Energy Colliders

The theoretical description of heavy quarkonium production at high-energy p-pbar and e-p colliders is reviewed. Predictions based on non-relativistic QCD factorisation are confronted with recent charmonium and bottomonium data from the Tevatron and HERA. Potential shortcomings of the present theoretical analyses are discussed, and the prospects for quarkonium physics at the upgraded Tevatron and HERA colliders and at the LHC are summarised.Comment: 61 pages, 20 figures. To be published in Progress in Particle and Nuclear Physics, Vol. 47, issue

Talin-KANK1 interaction controls the recruitment of cortical microtubule stabilizing complexes to focal adhesions

The cross-talk between dynamic microtubules and integrin-based adhesions to the extracellular matrix plays a crucial role in cell polarity and migration. Microtubules regulate the turnover of adhesion sites, and, in turn, focal adhesions promote cortical microtubule capture and stabilization in their vicinity, but the underlying mechanism is unknown. Here, we show that cortical microtubule stabilization sites containing CLASPs, KIF21A, LL5? and liprins are recruited to focal adhesions by the adaptor protein KANK1, which directly interacts with the major adhesion component, talin. Structural studies showed that the conserved KN domain in KANK1 binds to the talin rod domain R7. Perturbation of this interaction, including a single point mutation in talin, which disrupts KANK1 binding but not the talin function in adhesion, abrogates the association of microtubule-stabilizing complexes with focal adhesions. We propose that the talin-KANK1 interaction links the two macromolecular assemblies that control cortical attachment of actin fibers and microtubules

Do we achieve LDL-cholesterol targets in routine clinical practice? Evidence from a tertiary care hospital in Sri Lanka

Background: Statins are widely used for primary and secondary prevention of cardiovascular disease (CVD). European Society of Cardiology / European Atherosclerosis Society (ESC/EAS) guidelines recommend LDL-cholesterol targets based on CVD risk.Objectives: This study aimed to determine whether LDL-cholesterol targets recommended by2016 ESC/EASare achieved in routine clinical practice.Methods: This paper is based on baseline data of patients recruited to a controlled clinical trial conducted at a tertiary care hospital. Participants have been on atorvastatin for >2 months. Demographic and clinical data were obtained using clinic records and interviewer administered questionnaires. LDL-cholesterol was assessed using Friedewald equation (when triglyceride was <400mg/dL) or by direct measurement (when triglyceride was ≥400mg/dL). Each participant’s CVD risk level and appropriate LDL-cholesterol target (very-high CVD risk:<70mg/dL; high CVD risk:<100mg/dL; low to moderate CVD risk:<115mg/dL) was determined according to 2016 ESC/EAS Guideline.Results: 101 patients were studied. (Women: 76.2%; mean-age: 61.2:±9.3years). Prevalence of coronary heart disease, ischaemic stroke, diabetes, hypertension and smoking was 30.7%, 4%, 77.2%, 80.2% and 4%, respectively. According to CVD risk level 80.2%, 15.8% and 4% were in very-high, high and moderate risk categories, respectively. Most were on atorvastatin 10mg (45.5%) followed by 20mg (43.6%), 40mg (8.9%), 30mg (1%) and 5mg (1%). Median duration of treatment was 41-months. Overall, only 12.9% had achieved target LDL-cholesterol (very-high risk: 7.4%; high risk: 37.5%, moderate risk: 25%; p=0.003). Men did better than women in achieving target LDL-cholesterol (men: 29.2%, women: 7.8%; p=006). There was no difference based on age, comorbidities or atorvastatin dose.Conclusions: In the study population majority has failed to achieve LDL-cholesterol targets recommended by 2016 ESC/EAS. Failure to achieve targets was more common among women and those having very-high CVD risk. Reason for suboptimal target achievement has to be studied further.Acknowledgement: Funded by University of Sri Jayewardenepura Research Grant (ASP/01/RE/MED/2015/54) and Ceylon College of Physicians Research Grant (2014)

Platelet activating factor contributes to vascular leak in acute dengue infection

Background Although plasma leakage is the hallmark of severe dengue infections, the factors that cause increased vascular permeability have not been identified. As platelet activating factor (PAF) is associated with an increase in vascular permeability in other diseases, we set out to investigate its role in acute dengue infection. Materials and Methods PAF levels were initially assessed in 25 patients with acute dengue infection to determine if they were increased in acute dengue. For investigation of the kinetics of PAF, serial PAF values were assessed in 36 patients. The effect of dengue serum on tight junction protein ZO-1 was determined by using human endothelial cell lines (HUVECs). The effect of dengue serum on and trans-endothelial resistance (TEER) was also measured on HUVECs. Results PAF levels were significantly higher in patients with acute dengue (n = 25; p = 0.001) when compared to healthy individuals (n = 12). In further investigation of the kinetics of PAF in serial blood samples of patients (n = 36), PAF levels rose just before the onset of the critical phase. PAF levels were significantly higher in patients with evidence of vascular leak throughout the course of the illness when compared to those with milder disease. Serum from patients with dengue significantly down-regulated expression of tight junction protein, ZO-1 (p = 0.004), HUVECs. This was significantly inhibited (p = 0.004) by use of a PAF receptor (PAFR) blocker. Serum from dengue patients also significantly reduced TEER and this reduction was also significantly (p = 0.02) inhibited by prior incubation with the PAFR blocker. Conclusion Our results suggest the PAF is likely to be playing a significant role in inducing vascular leak in acute dengue infection which offers a potential target for therapeutic intervention

QCD and strongly coupled gauge theories : challenges and perspectives

We highlight the progress, current status, and open challenges of QCD-driven physics, in theory and in experiment. We discuss how the strong interaction is intimately connected to a broad sweep of physical problems, in settings ranging from astrophysics and cosmology to strongly coupled, complex systems in particle and condensed-matter physics, as well as to searches for physics beyond the Standard Model. We also discuss how success in describing the strong interaction impacts other fields, and, in turn, how such subjects can impact studies of the strong interaction. In the course of the work we offer a perspective on the many research streams which flow into and out of QCD, as well as a vision for future developments.Peer reviewe

Spin-Flip Interactions and the Puzzle of psi's Polarization at Tevatron

Nonrelativistic QCD provides a systematic approach for inclusive decays and productions of a quarkonium. By taking color-octet components into account, the approach can explain the $\psi'$-anomaly at Tevatron, where the measured production rate at large transverse momentum $p_\perp$ is in order of magnitude larger than the predicted with color-singlet components only. With the approach one can predict that the produced $J/\psi$ and $\psi'$ at large $p_\perp$ will be transversely polarized. But the prediction fails in confronting with experimental measurements and this generates a puzzle. We examine the role of spin-flip interactions in the spin density matrix of the transition of a color-octet charm quark pair into $J/\psi$ and $\psi'$. These interactions will introduce new nonperturbative parameters in the spin density matrix. Our result shows that the impact of the interactions is always to dilute the polarization and can be very significant. Taking the impact into account, predictions for the polarization are more close to the measured than the previous predicted. The same can also be expected for the polarization of $J/\psi$.Comment: match the published version Phys.Lett.B645:180-184,200

The Color Singlet Relativistic Correction in J/ψJ/\psi Photoproduction

The $O(v^2)$ relativistic correction for inelastic $J/\psi$ photoproduction, in which heavy quark pairs are in the dominant Fock state of the quarkonium, is studied in the framework of NRQCD factorization. An assessment of its significance, particularly in comparison to the color octet contributions, is made. It is found that the impact on the energy distribution is negative in certain regions of phase space. The predictions are compared with photoproduction data from DESY-HERA.Comment: 12 pages, 5 figures, LaTex, new figure

Laminin-based cell adhesion anchors microtubule plus ends to the epithelial cell basal cortex through LL5α/β

A newly discovered interaction between LL5s, laminins, and integrins reveals how the extracellular matrix directs microtubule polarity in epithelial tissues