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Islet transplantation is a potential treatment option for certain patients with type 1 diabetes; however, it still faces barriers to widespread use, including the lack of tools to monitor islet grafts post-transplantation. This study investigates whether labeling neonatal porcine islets (NPI) with polyvinylpyrrolidone-coated superparamagnetic iron oxide nanoparticles (PVP-SPIO) affects their function, and whether this nanoparticle can be utilized to monitor NPI xenografts with magnetic resonance imaging (MRI) in a mouse model. In vitro, PVP-SPIO-labeled NPI in an agarose gel was visualized clearly by MRI. PVP-SPIO-labeled islets were then transplanted under the kidney capsules of immunodeficient nondiabetic and diabetic mice. All diabetic mice that received transplantation of PVP-SPIO-labeled islets reached normoglycemia. Grafts appeared as hypo-intense areas on MRI and were distinguishable from the surrounding tissues. Following injection of spleen cells from immunocompetent mice, normoglycemic recipient mice became diabetic and islet grafts showed an increase in volume, accompanied by a mixed signal on MRI. Overall, this study demonstrates that PVP-SPIO did not affect the function of NPI that PVP-SPIO-labeled islets were easily seen on MRI, and changes in MRI signals following rejection suggest a potential use of PVP-SPIO-labeled islets to monitor graft viability.

We uncover the relationship of topology and disorder in a one-dimensional Su-Schrieffer-Heeger chain subjected to a slowly varying quasi-periodic modulation. By numerically calculating the disorder-averaged winding number and analytically studying the localization length of the zero modes, we obtain the topological phase diagram, which implies that the topological Anderson insulator (TAI) can be induced by a slowly varying quasi-periodic modulation. Moreover, unlike the localization properties in the TAI phase caused by random disorder, mobility edges can enter into the TAI region identified by the fractal dimension, the inverse participation ratio, and the spatial distributions of the wave functions, the boundaries of which coincide with our analytical results., Comment: 9 pages, 8 figures

Alumina (Al2O3) ceramics were prepared with nucleating agent of titania (TiO2) and fluxing agent of talc by the normal pressure sintering method. The effects of TiO2 and talc on phase composition, microstructure, and mechanical properties of Al2O3 ceramics, as well the strengthening and toughening mechanism were investigated. It was found that the introduction of TiO2 could be favorable for mullite formation and the improved densification of ceramics, resulting in improved mechanical properties of ceramics as well. Ceramics possess the best comprehensive mechanical performance with fracture toughness of 3.69 MPa·m1/2 and flexural strength of 255.9 MPa when 4 wt.% TiO2 and 15 wt.% talc were added. Mineral bridges and nanocrystallites were found in the glass-ceramics, which caused the deflection of cracks so that it strengthened the grain boundary and improved the mechanical properties of ceramics.

Along with globalization, countries consume a large amount of goods and services from both domestic and international markets. As one of the world's largest agricultural countries, China is faced with serious water scarcity and has to reduce the water consumption from both domestic and global aspects, of which the crop planting structure optimization (CPSO) between regions based on the virtual water perspective could be a solution for efficient agricultural water consumption. In this article, three scenarios of Chinese agriculture, including agricultural water consumption restrictions relaxed scenario, agricultural water consumption limited scenario, and net utilization ratio of water resources limited scenario, were designed to minimize the national agricultural water consumption under various water, land, and crop planting constraints in individual provinces and analyze the impacts of the CPSO. The results showed that compared with the historical situation of crop planting in 2007, 53.3%, 51.4%, and 47.3% of the agricultural water consumption and more than 10% of the sown area of China was saved under the three scenarios, respectively. Because of the reduction of agricultural water consumption and land use, it brought about the expansion of crops production in China. CPSO is found to have notable effects on water saving and food security considering the dependence of the crops by international trade.

We present an algorithm for estimating the six degrees of freedom 6DOF pose for a rigid object of arbitrary shape, which can move fast in cluttered environments. The RGBD data input is obtained by fusing a time-of-flight TOF camera and a color camera. The proposed approach is composed of a coarse estimation stage for prealignment and an accurate estimation stage for refining the coarse pose. The most important contribution is the textured iterative closest point ICP in the accurate stage, where the Lukas-Kanade method is incorporated into the point-to-plane ICP framework, by which geometrically symmetric objects can be handled. In addition, the pose estimation performance under motion artifacts that are common for a TOF sensor can be significantly improved. Another important contribution is the tailored sparse representation under an annealed particle filtering framework for effectively extracting the target from the background clutter and providing a coarse 6DOF pose. The entire algorithm is implemented with graphics processing unit acceleration and shows real-time performance. The approach is verified on a variety of targets in both indoor and outdoor scenarios.

Background and objective: Pulmonary alveolar proteinosis (PAP) is a rare pulmonary disease. It was first described in China in 1965, and more cases have been reported subsequently. A systematic review was performed on 241 cases of PAP in China and progress in the diagnosis and treatment of this disease is discussed. Methods: The Chinese biological and medical databases from 1965 to 2006 were searched and 241 cases with complete clinical and pathological data were identified. The clinical characteristics of the disease were summarized and longitudinal comparisons were made of diagnostic and treatment methods over time. Results: The morbidity associated with PAP has increased in recent years. The clinical manifestations were non-specific. Progressive dyspnoea, cough and sputum were the most common symptoms. The percentage of patients undergoing CT examination has increased over the years. The combination of bronchoscopic biopsy and bronchoalveolar lavage (BAL) was usually sufficient to establish the diagnosis. Treatment was reported for a total of 142 cases. BAL and whole lung lavage were both effective and were only required once by most patients. Conclusions: The demographic characteristics and clinical manifestations of PAP patients in China are largely consistent with previous reports. Morbidity has increased dramatically in recent years, mainly due to the broad application of bronchoscopy since 1995. CT is very important for diagnosis of the disease. The long-term effects of treatment by whole lung lavage and BAL are similar.

Ti-Nb-O binary oxide materials represent a family of promising intercalating anode materials for lithium-ion batteries. In additional to their excellent capacities (388-402 mAh g-1 ), these materials show excellent safety characteristics, such as an operating potential above the lithium plating voltage and minimal volume change. Herein, this study reports a new member in the Ti-Nb-O family, Ti2 Nb14 O39 , as an advanced anode material. Ti2 Nb14 O39 porous spheres (Ti2 Nb14 O39 -S) exhibit a defective shear ReO3 crystal structure with a large unit cell volume and a large amount of cation vacancies (0.85% vs all cation sites). These morphological and structural characteristics allow for short electron/Li+ -ion transport length and fast Li+ -ion diffusivity. Consequently, the Ti2 Nb14 O39 -S material delivers significant pseudocapacitive behavior and excellent electrochemical performances, including high reversible capacity (326 mAh g-1 at 0.1 C), high first-cycle Coulombic efficiency (87.5%), safe working potential (1.67 V vs Li/Li+ ), outstanding rate capability (223 mAh g-1 at 40 C) and durable cycling stability (only 0.032% capacity loss per cycle over 200 cycles at 10 C). These impressive results clearly demonstrate that Ti2 Nb14 O39 -S can be a promising anode material for fast-charging, high capacity, safe and stable lithium-ion batteries.