Outcome of posterior wall blowout in anterior cruciate ligament (ACL) reconstruction via anteromedial portal approach: A retrospective research in 20 patients with 6 years follow-up

Purpose: To evaluate the clinical outcome in patients who received anterior cruciate ligament (ACL) rec on structi on via an teromedial portal with or without posterior wall blowout. Methods: Twenty patients w让h ruptured ACL, who have received ACL reconstruction via anteromedial portal between Apr 2012 and Oct 2013 were enrolled. According to the conditions of posterior wall, the patients were divided into 2 groups: posterior wall blowout group (10 patients) and posterior wall intact group (10 patients). The median follow up time were 63 (range 19-75) months and 60.5 (range 25—64) months in the 2 groups respectively. The clinical outcome was evaluated by knee joint physical examinati on, mag netic resonance imaging (MRI), the Inter national Knee Docume ntation Comm 让 tee (IKDC) 2000 subjective score, Lysholm score. Ten ger score, difference of thigh circumfere nee, KT-2000 and Biodex isokinetic dynamometer system. Results: No significant differences were found in terms of the IKDC score, Lysholm score, Tegner score, Lachman test positive rate or Pivot Shift test positive rate between the two groups. In KT-2000 and Biodex isokinetic dynamometer tests, the differenee of muscle strength between affected knees and unaffected knees in posterior wall blowout group was not significant less than that of posterior wall intact group (p > 0.05). In addition, there is no statistical difference between the two groups in signal/ noise quotient (SNQ) of the graft (p > 0.05) in post operative MRI. Conclusion: Blowout of posterior wall in ACL reconstruction via anteromedial portal does not affect the clinical outcome as long as reliable fixation has been taken intraoperatively.

Bisperylene Bisimide Based Conjugated Polymer as Electron Acceptor for Polymer-Polymer Solar Cells

Perylene bisimide （PBI） unit has been widely used to design conjugated materials, which can be used as electron acceptor in organic solar ceils due to its strong electron-deficient ability. In this work, a conjugated polymer based on PBI dimer as monomer was designed, synthesized, and compared to the conjugated polymer containing single PBI as repeating units. The two conjugated polymers were found to have similar molecular weight, absorption spectra and energy levels. Density functional theory calculation revealed that the PBI dimer-based polymer exhibited highly twisted conjugated backbone due to the large dihedral angle between the two PBI units. The PBI-based polymers as electron acceptor were applied into polymer-polymer solar cells, in which PBI dimer-based polymer solar cells were found to show a high short circuit current density （Jsc = 11.2 mA.cm-2） and a high power conversion efficiency （PCE） of 4.5%. In comparison, the solar cells based on PBI-based polymer acceptor only provided a dsc of 7.2 mA.cm-2 and PCE of 2.5%. The significantly enhanced PCE in PBI dimer-based solar cells was attributed to the mixed phase in blended thin films, as revealed by atom force microscopy. This study demonstrates that PB! dimer can be used to design polymer acceptors for high performance polymer- polymer solar cells.

Review:Image anti-aliasing techniques for Internet visual media processing: a review

Anti-aliasing is a well-established technique in computer graphics that reduces the blocky or stair-wise appearance of pixels. This paper provides a comprehensive overview of the anti-aliasing techniques used in computer graphics, which can be classified into two categories: post-filtering based anti-aliasing and pre-filtering based anti-aliasing. We discuss post-filtering based anti-aliasing algorithms through classifying them into hardware anti-aliasing techniques and post-process techniques for deferred rendering. Comparisons are made among different methods to illustrate the strengths and weaknesses of every category. We also review the utilization of anti-aliasing techniques from the first category in different graphic processing units, i.e., different NVIDIA and AMD series. This review provides a guide that should allow researchers to position their work in this important research area, and new research problems are identified.