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Radar Target Recognition (RTR) is one of the most important needs of modern and future airborne surveillance radars, and it is still one of the key technologies of radar. The majority of present algorithms are based on wide-band radar signal, which not only needs high performance radar system and high target Signal-to-Noise Ratio (SNR), but also is sensitive to angle between radar and target. Low-Resolution Airborne Surveillance Radar (LRASR) in downward-looking mode, slow flying aircraft and ground moving truck have similar Doppler velocity and Radar Cross Section (RCS), leading to the problem that LRASR air/ground moving targets can not be distinguished, which also disturbs detection, tracking, and classification of low altitude slow flying aircraft to solve these issues, an algorithm based on narrowband fractal feature and phase modulation feature is presented for LRASR air/ground moving targets classification. Real measured data is applied to verify the algorithm, the classification results validate the proposed method, helicopters and truck can be well classified, the average discrimination rate is more than 89% when SNR ≥ 15 dB.

Target classification is particularly important in modern and future airborne radar. Nowadays, most investigations of radar target classification are based on wideband radar signals, which have higher requirements for SNR and radar systems, and are sensitive to the angles. Modern airborne radars require narrowband tracking and target classification; hence, an algorithm based on the narrowband fractal features and the amplitude modulation of a two-dimensional distribution is presented. Experimental data and Support Vector Machine (SVM) are used to verify the algorithm, and the classification results validate the proposed method, which show that jet aircrafts, propeller aircrafts, and helicopters can be classified with an average discrimination rate greater than 92%.

Background: The reductions of perioperative blood loss and inflammatory response are important in total knee arthroplasty. Tranexamic acid reduced blood loss and the inflammatory response in several studies. However, the effect of epinephrine administration plus tranexamic acid has not been intensively investigated, to our knowledge. In this study, we evaluated whether the combined administration of low-dose epinephrine plus tranexamic acid reduced perioperative blood loss or inflammatory response further compared with tranexamic acid alone.Methods: This randomized placebo-controlled trial consisted of 179 consecutive patients who underwent primary total knee arthroplasty. Patients were randomized into 3 interventions: Group IV received intravenous low-dose epinephrine plus tranexamic acid, Group TP received topical diluted epinephrine plus tranexamic acid, and Group CT received tranexamic acid alone. The primary outcome was perioperative blood loss on postoperative day 1. Secondary outcomes included perioperative blood loss on postoperative day 3, coagulation and fibrinolysis parameters (measured by thromboelastography), inflammatory cytokine levels, transfusion values (rate and volume), thromboembolic complications, length of hospital stay, wound score, range of motion, and Hospital for Special Surgery (HSS) score.Results: The mean calculated total blood loss (and standard deviation) in Group IV was 348.1 ± 158.2 mL on postoperative day 1 and 458.0 ± 183.4 mL on postoperative day 3, which were significantly reduced (p < 0.05) compared with Group TP at 420.5 ± 188.4 mL on postoperative day 1 and 531.1 ± 231.4 mL on postoperative day 3 and Group CT at 520.4 ± 228.4 mL on postoperative day 1 and 633.7 ± 237.3 mL on postoperative day 3. Intravenous low-dose epinephrine exhibited a net anti-inflammatory activity in total knee arthroplasty and did not induce an obvious hypercoagulable status. Transfusion values were significantly reduced (p < 0.05) in Group IV, but no significant differences were observed in the incidence of thromboembolic complications, wound score, range of motion, and HSS score among the 3 groups (p > 0.05).Conclusions: The combined administration of low-dose epinephrine and tranexamic acid demonstrated an increased effect in reducing perioperative blood loss and the inflammatory response compared with tranexamic acid alone, with no apparent increased incidence of thromboembolic and other complications.Level Of Evidence: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Objective To develop a dressing with desired antibacterial activity, good water maintaining ability and mechanical properties for wound healing and skin regeneration. Methods The chitosan with different concentrations were added in keratin solution to form porous keratin/chitosan (KCS) scaffolds. The morphological characteristics, chemical composition, wettability, porosity, swelling ratio and degradation of the scaffolds were evaluated. The antibacterial activity was tested by using S. aureus and E. coli suspension for 2 h. And L929 fibroblast cells culture was used to evaluate the cytotoxicity of the KCS scaffolds. Results The adding of chitosan could increase the hydrophobicity, decrease porosity, swelling ratio and degradation rate of the KCS porous scaffolds. Mechanical properties of KCS scaffolds could be enhanced and well adjusted by chitosan. KCS scaffolds could obviously decrease bacteria number. The proliferation of fibroblast cells in porous KCS patch increased firstly and then decreased with the increase of chitosan concentration. It was appropriate to add 400 μg/mL chitosan to form porous KCS scaffold for achieving best cell attachment and proliferation compared with other samples. Conclusion The porous KCS scaffold may be used as implanted scaffold materials for promoting wound healing and skin regeneration. [ABSTRACT FROM AUTHOR]

The essence of property collection lies in that the country want to realize the public interests by nationalization as the owner of administrative power, and its value is based on the distributive justice, not exchange justice. The proposition of property collection is a field of public law, the core of which lies in the restrictions on executive power rather than the socialization of ownership, and the crux of the theory and practice of which is the private law of property collection. The achievement of public interest should be imposed to institutional innovation as the logical starting point, specifically as follows. China should emphasize to promote the public interest based on realizing public ownership, collection should be an exceptional means, and the collection process should establish the thought of "housing first on the land" to safeguard the rights and interests of the expropriated in the collection process. Start and completion of the collection will have to accept the detection of public interests, and compensation should take full account of contribution of the expropriated to the public interests. [ABSTRACT FROM AUTHOR]

Purpose: To compare clinical follow-up results of anterior cruciate ligament (ACL) reconstruction using (1) autologous, (2) fresh-frozen allogeneic, and (3) γ-irradiated allogeneic bone-patellar tendon-bone (BPTB)., Methods: From February 2002 to January 2006, 187 patients received BPTB ACL reconstruction at our center. One hundred forty-two consecutive patients who had received single-bundle BPTB ACL reconstruction were included in this study. Of these patients, 41 had autografts, 33 had fresh-frozen allografts, and 68 had γ-irradiated allografts. Clinical results were evaluated with the KT-1000 maximum displacement test (MEDmetric, San Diego, CA), Lachman test, and Lysholm, Irrgang, and Larson activity scales., Results: The mean duration of follow-up was 6.7 ± 1.5 years (range, 4.2 to 8.2 years). There were 3 cases of acute synovitis due to immunologic rejection (fresh-frozen allografts) and 6 cases of failure (γ-irradiated allografts). KT-1000 examination showed more anterior laxity in the γ-irradiated allograft group compared with the autograft and fresh-frozen allograft groups (P < .05). The Lysholm, Irrgang, and Larson activity scales showed no difference among the 3 groups (P > .05)., Conclusions: The study showed a statistically poorer KT-1000 result and higher failure rate in the γ-irradiated allograft group compared with the autograft and fresh-frozen allograft groups. This may suggest that γ-irradiated allograft is not a good candidate graft for ACL reconstruction. Power analysis showed that the study was underpowered, so further research and longer follow-up study are needed to make this point clearer., Level of Evidence: Level III, retrospective comparative study., (Copyright © 2012 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)