Three dimensional anatomy of the anterior cruciate ligament: a new approach in anatomical orthopedic studies and a literature review

Background: The anterior cruciate ligament (ACL) is an important structure in the knee. The ACL does not heal following lesions, and surgical reconstruction is the standard treatment among athletes. Some steps of ACL reconstruction remain controversial. It is important to fully understand the anatomy of the ACL to accurately reproduce its anatomy during surgical reconstructions. The purpose of this study was to evaluate the use of anaglyphic images that produce 3D images to better visualize the anatomy of the ACL, and to highlight the anatomical features of this ligament as reported in the literature.Methods: We included ten knees in this study. After dissection of the knee structures, pictures were acquired using a camera with Nikon D40, AF-S Nikkor 18-55 mm (1:3.5-5.6 G2 ED), and Micro Nikkor 105 mm (1:2.8) lenses. The pair of images was processed using Callipyan 3D Anabuilder software, which transforms the two images into one anaglyphic image.Results: During the dissection of the knees, nine pictures were acquired and transformed into anaglyphic images.Conclusion: This study, demonstrated that the use of 3D images is a useful tool that can improve the knowledge of the anatomy of the knee, while also facilitating knee reconstruction surgery

The effects of one-half of a soccer match on the postural stability and functional capacity of the lower limbs in young soccer players

OBJECTIVE: Most injuries occur during the final 15 minutes of each half of a soccer match, suggesting that physical exertion may influence changes in neuromuscular control and the body's ability to stabilize the joints of the lower extremities. The aim of this study was to analyze the effects of one-half of a soccer match on the functional capacity and stability of the lower limbs in young soccer players. METHODS: We analyzed 27 soccer players by evaluating the functional capacity of their lower limbs using the hop test protocol and their level of postural stability using the Biodex Stability System. The evaluations were performed before and after 45 minutes of game time. RESULTS: After the match, there was a decrease in the overall stability index (OSI) (F(1,23) = 5.64, p = 0.026) and the anterior-posterior stability index (APSI) (F(1,23) = 5.24,p = 0.032). In the single and triple hop tests, there was a higher functional capacity in the dominant limb compared to the non dominant limb in the pre- and post-game comparisons. CONCLUSION: The results of this study show that there is a decrease in the stability of the lower limbs in young soccer players after a 45 minutes soccer match, but the same result was not found for the functional capacity.Universidade Federal de São Paulo (UNIFESP) Centro de Traumatologia do Esporte Departamento de Ortopedia e TraumatologiaUNIFESP, Centro de Traumatologia do Esporte Depto. de Ortopedia e TraumatologiaSciEL

Limits on WWgamma and WWZ Couplings from W Boson Pair Production

The results of a search for W boson pair production in pbar-p collisions at sqrt{s}=1.8 TeV with subsequent decay to emu, ee, and mumu channels are presented. Five candidate events are observed with an expected background of 3.1+-0.4 events for an integrated luminosity of approximately 97 pb^{-1}. Limits on the anomalous couplings are obtained from a maximum likelihood fit of the E_T spectra of the leptons in the candidate events. Assuming identical WWgamma and WWZ couplings, the 95 % C.L. limits are -0.62<Delta_kappa<0.77 (lambda = 0) and -0.53<lambda<0.56 (Delta_kappa = 0) for a form factor scale Lambda = 1.5 TeV.Comment: 10 pages, 1 figure, submitted to Physical Review

Search For Heavy Pointlike Dirac Monopoles

We have searched for central production of a pair of photons with high transverse energies in $p\bar p$ collisions at $\sqrt{s} = 1.8$ TeV using $70 pb^{-1}$ of data collected with the D\O detector at the Fermilab Tevatron in 1994--1996. If they exist, virtual heavy pointlike Dirac monopoles could rescatter pairs of nearly real photons into this final state via a box diagram. We observe no excess of events above background, and set lower 95% C.L. limits of $610, 870, or 1580 GeV/c^2$ on the mass of a spin 0, 1/2, or 1 Dirac monopole.Comment: 12 pages, 4 figure

Limits on Anomalous WWgamma and WWZ Couplings

Limits on the anomalous WWgamma and WWZ couplings are presented from a simultaneous fit to the data samples of three gauge boson pair final states in pbar-p collisions at sqrt(s)=1.8 TeV: Wgamma production with the W boson decaying to enu or munu, W boson pair production with both of the W bosons decaying to enu or munu, and WW or WZ production with one W boson decaying to enu and the other W boson or the Z boson decaying to two jets. Assuming identical WWgamma and WWZ couplings, 95 % C.L. limits on the anomalous couplings of -0.30<Delta kappa<0.43 (lambda = 0) and -0.20<lambda<0.20 (Delta kappa = 0) are obtained using a form factor scale Lambda = 2.0 TeV. Limits found under other assumptions on the relationship between the WWgamma and WWZ couplings are also presented.Comment: 13 pages, 3 figures, submitted to Physical Review

Second Generation Leptoquark Search in p\bar{p} Collisions at s\sqrt{s} = 1.8 TeV

We report on a search for second generation leptoquarks with the D\O\ detector at the Fermilab Tevatron $p\bar{p}$ collider at $\sqrt{s}$ = 1.8 TeV. This search is based on 12.7 pb$^{-1}$ of data. Second generation leptoquarks are assumed to be produced in pairs and to decay into a muon and quark with branching ratio $\beta$ or to neutrino and quark with branching ratio $(1-\beta)$. We obtain cross section times branching ratio limits as a function of leptoquark mass and set a lower limit on the leptoquark mass of 111 GeV/c$^{2}$ for $\beta = 1$ and 89 GeV/c$^{2}$ for $\beta = 0.5$ at the 95%\ confidence level.Comment: 18 pages, FERMILAB-PUB-95/185-

Search for Top Squark Pair Production in the Dielectron Channel

This report describes the first search for top squark pair production in the channel stop_1 stopbar_1 -> b bbar chargino_1 chargino_1 -> ee+jets+MEt using 74.9 +- 8.9 pb^-1 of data collected using the D0 detector. A 95% confidence level upper limit on sigma*B is presented. The limit is above the theoretical expectation for sigma*B for this process, but does show the sensitivity of the current D0 data set to a particular topology for new physics.Comment: Five pages, including three figures, submitted to PRD Brief Report

Measurement of the WW Boson Mass

A measurement of the mass of the $W$ boson is presented based on a sample of 5982 $W \rightarrow e \nu$ decays observed in $p\overline{p}$ collisions at $\sqrt{s}$ = 1.8~TeV with the D\O\ detector during the 1992--1993 run. From a fit to the transverse mass spectrum, combined with measurements of the $Z$ boson mass, the $W$ boson mass is measured to be $M_W = 80.350 \pm 0.140 (stat.) \pm 0.165 (syst.) \pm 0.160 (scale) GeV/c^2$.Comment: 12 pages, LaTex, style Revtex, including 3 postscript figures (submitted to PRL

Search for First Generation Scalar Leptoquark Pairs in ppbar Collisions at sqrt(s)=1.8 TeV

We have searched for first generation scalar leptoquark (LQ) pairs in the enu+jets channel using ppbar collider data (integrated luminosity= 115 pb^-1) collected by the DZero experiment at the Fermilab Tevatron during 1992-96. The analysis yields no candidate events. We combine the results with those from the ee+jets and nunu+jets channels to obtain 95% confidence level (CL) upper limits on the LQ pair production cross section as a function of mass and of beta, the branching fraction to a charged lepton. Comparing with the next-to-leading order theory, we set 95% CL lower limits on the LQ mass of 225, 204, and 79 GeV/c^2 for beta=1, 1/2, and 0, respectively.Comment: 14 pages, 4 figures, submitted to Physical Review Letters Replaced to correct visitor addresse

La estrategia de movilidad académica del Sector Educativo del MERCOSUR: balance y desafíos

El presente artículo constituye un relato acerca de la trayectoria y evolución de la estrategia de movilidad académica que ha desarrollado el Sector Educativo del MERCOSUR (SEM) desde su creación en el año 1991. Se trata de presentar el enfoque a nivel de la mirada estratégica del Sector, principalmente plasmada a través de sus planes de acción y mediante la caracterización y desarrollo de las iniciativas concretas de movilidad académica que han tenido lugar desde su creación. El trabajo tratará de caracterizar los aspectos más sobresalientes que ha tenido el abordaje y efectuar un balance acerca de la situación actual y los desafíos futuros