Search

This paper proposes a novel multiple watermarking scheme based on orthogonal decomposition (MWOD). In the first phase, based on orthogonal decomposition, the host data selected from multimedia data are divided into mutually independent multiple domains. Then multiple watermarks without need for considering the special correlation among them can respectively be embedded into these different domains even using different embedding algorithms. There is no mutual interference among watermarked domains so that multiple watermarks can be flexibly embedded in the distribution of the multimedia cover. Through theoretical analysis, the security of multiple watermarking operands is validated, which means that MWOD can ensure the security of watermarking operation domains. Therefore, media providers and service providers can embed their unique information step-by-step into digital multimedia using their own operation domain keys in MWOD, which can be used to identify media content's ownership or trace the illegal redistributors. Experimental results and analysis demonstrate the feasibility and robustness of MWOD. [ABSTRACT FROM AUTHOR]

Background: There is limited evidence to guide treatment for pediatric cervical spinal tuberculosis with kyphosis (PCSTK). This study retrospectively evaluates the safety, feasibility and efficacy of 360-degree arthrodesis combined with anterior debridement and decompression for treating PCSTK, while simultaneously emphasizing the role of posterior fixation for the correction and maintenance of the kyphosis angle. Methods: From May 2006 to December 2012, a total of 12 children with PCSTK underwent 360-degree cervical spinal arthrodesis followed by debridement of focus and decompression of the spinal cord. Data on the angle of kyphosis correction, visual analogue scale scores of pain, the American Spinal Injury Association scoring system of nerve function scores, erythrocyte sedimentation rate (ESR) and body weight were collected at certain periods. Clinical efficacy was evaluated by statistical analysis based on collected data. Results: Average follow-up period was 34.3 ± 8.6 months. No postoperative complications related to the instrumentation occurred, and neurologic function improved in various degrees. Preoperative kyphosis angle was 41.4 ± 5.2°, and significantly decreased to -4.9 ± 4.9° after surgery. The correction of kyphosis and loss of correction were 47.1 ± 4.9° and 0.6 ± 1.4°, respectively. Average pretreatment ESR was 49.8 ± 13.2 mm/h, which normalized (8.5 ± 0.6 mm/h) within three months in all patients. Average preoperative visual analogue scale was 6.6 ± 1.6, which decreased to 2.3 ± 1.4 postoperatively and 0.3 ± 0.5 during the final follow-up. Mean preoperative body weight was 25.9 ± 5.1 kg, and body weight was 33.5 ± 4.8 kg at the third month of post-operation. Bone healing was achieved in all patients after a mean period of 5.4 months. Conclusions: 360-degree arthrodesis combined with anterior debridement and decompression is a safe and effective method for the treatment of PCSTK. For the correction and maintenance of the kyphosis angle, additional posterior fixation is recommended. [ABSTRACT FROM AUTHOR]

Exploring new optical thermometric materials is important to realize highly accurate temperature detecting. Herein, Yb/Er activators are successfully doped into Cs 2 Ag(In/Bi)Cl 6 lead-free double perovskite (DP) semiconductor, providing dual-modal photoluminescence originated from self-trapped exciton recombination and 4f-4f transitions of Yb/Er dopants as well as Er3+ upconversion emissions. Remarkably different temperature-dependent emissive behaviors from DP host and Yb/Er activators are experimentally demonstrated, which enables to design novel fluorescence intensity ratio (FIR) between DP and Yb/Er based thermometric technology. In addition, upconversion FIR-based temperature sensing via thermal population between the 2H 11/2 level and 4S 3/2 one of Er3+ dopants in DP host is also realized. It is believed that the present Yb/Er: Cs 2 Ag(In/Bi)Cl 6 DP with excellent long-term stability and dual-functional temperature detecting is a suitable candidate as the self-calibrated optical thermometric material. The combination of the exciton recombination of Cs 2 AgInCl 6 lead-free double perovskite with Ln3+ (Ln = Yb, Er) dopants induces dual-modal light-emitting channel to produce a novel thermometric material. [Display omitted] • Yb/Er: Cs 2 Ag(In/Bi)Cl 6 lead-free double perovskite is successfully prepared. • The product exhibits both self-trapped exciton recombination and Ln3+: 4f-4f emissions. • Different temperature-dependent emissive behaviors from host and Ln3+ activators are demonstrated. • A novel DP/Ln3+ fluorescence intensity ratio thermometric channel is developed. • The product is a promising candidate for dual-modal optical temperature sensing. [ABSTRACT FROM AUTHOR]