Reconstruction of the anterior cruciate ligament with quadriceps tendon.

We found 1 article: Arthroscopy. 2002 Sep;18(7):E37. Reconstruction of the anterior cruciate ligament with quadriceps tendon. Noronha JC. Department of Trauma and Orthopaedic Surgery, Hospital Santo António, Porto, Portugal. [email protected] Abstract The author describes the technique he uses to reconstruct the anterior cruciate ligament (ACL) arthroscopically with autologous bone-quadriceps tendon (BQT) graft. The patellar bone is fixed in a femoral tunnel about 2.5 cm long, in a position that allows the tendinous extremity of the graft to appear on the extra-articular exit of the tibial tunnel. The tibial tunnel is filled, making the integration of the tendon in the bone easier. The tendinous extremity of the graft is pulled by nonabsorbable wires, remaining strictly fixed by a staple or a screw in the anterointernal cortex of the tibia. When used in selected cases and when technical details are respected, this technique yields results similar to those obtained with the bone-patella tendon-bone (BPTB) graft. The functional recovery should be more careful with this technique than when the BPTB is used. Generally, less morbidity is seen with the BQT graft. The author believes that the BQT graft will be used more frequently, especially in ACL reconstruction, for patients whose jobs require kneeling or long periods of knee flexion, or in cases of low patella, patellar chondropathy, or tendinopathy of the patellar tendon. This technique may also be appropriate for revision surgeries. PMID: 12209422 [PubMed - indexed for MEDLINE

Glueballs, gluon condensate, and pure glue QCD below T_c

A quasiparticle description of pure glue QCD thermodynamics at T<T_c is proposed and compared to recent lattice data. Given that a gas of glueballs with constant mass cannot quantitatively reproduce the early stages of the deconfinement phase transition, the problem is to identify a relevant mechanism leading to the observed sudden increase of the pressure, trace anomaly, etc. It is shown that the strong decrease of the gluon condensate near T_c combined with the increasing thermal width of the lightest glueballs might be the trigger of the phase transition.Comment: 5 pages, 5 figures; analysis refined in v2, explanations added; v3 to appear in EPJ

Magnetism in Dense Quark Matter

We review the mechanisms via which an external magnetic field can affect the ground state of cold and dense quark matter. In the absence of a magnetic field, at asymptotically high densities, cold quark matter is in the Color-Flavor-Locked (CFL) phase of color superconductivity characterized by three scales: the superconducting gap, the gluon Meissner mass, and the baryonic chemical potential. When an applied magnetic field becomes comparable with each of these scales, new phases and/or condensates may emerge. They include the magnetic CFL (MCFL) phase that becomes relevant for fields of the order of the gap scale; the paramagnetic CFL, important when the field is of the order of the Meissner mass, and a spin-one condensate associated to the magnetic moment of the Cooper pairs, significant at fields of the order of the chemical potential. We discuss the equation of state (EoS) of MCFL matter for a large range of field values and consider possible applications of the magnetic effects on dense quark matter to the astrophysics of compact stars.Comment: To appear in Lect. Notes Phys. "Strongly interacting matter in magnetic fields" (Springer), edited by D. Kharzeev, K. Landsteiner, A. Schmitt, H.-U. Ye

A contracting model for flexible distributed scheduling

We are interested in building systems of autonomous agents that can automate routine information processing activities in human organizations. Computational infrastructures for cooperative work should contain embedded agents for handling many routine tasks [9], but as the number of agents increases and the agents become geographically and/or conceptually dispersed, supervision of the agents will become increasingly problematic. We argue that agents should be provided with deep domain knowledge that allows them to make quantitatively justifiable decisions, rather than shallow models of users to mimic. In this paper, we use the application domain of distributed meeting scheduling to investigate how agents embodying deeper domain knowledge can choose among alternative strategies for searching their calendars in order to create flexible schedules within reasonable cost.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44288/1/10479_2005_Article_BF02187332.pd

One sixth of Amazonian tree diversity is dependent on river floodplains

Amazonia's floodplain system is the largest and most biodiverse on Earth. Although forests are crucial to the ecological integrity of floodplains, our understanding of their species composition and how this may differ from surrounding forest types is still far too limited, particularly as changing inundation regimes begin to reshape floodplain tree communities and the critical ecosystem functions they underpin. Here we address this gap by taking a spatially explicit look at Amazonia-wide patterns of tree-species turnover and ecological specialization of the region's floodplain forests. We show that the majority of Amazonian tree species can inhabit floodplains, and about a sixth of Amazonian tree diversity is ecologically specialized on floodplains. The degree of specialization in floodplain communities is driven by regional flood patterns, with the most compositionally differentiated floodplain forests located centrally within the fluvial network and contingent on the most extraordinary flood magnitudes regionally. Our results provide a spatially explicit view of ecological specialization of floodplain forest communities and expose the need for whole-basin hydrological integrity to protect the Amazon's tree diversity and its function.Naturali