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Polydopamine (PDA) was coated on poly(vinylidene fluoride) (PVDF) membranes with different structures to select the most suitable structure for achieving outstanding hydrophilicity, permeability, stability, and antifouling properties. PVDF membranes were prepared with different solvents (N‐methyl‐2‐pyrrolidone [NMP], N,N‐dimethylacetamide [DMAc], N,N‐dimethylformamide [DMF], NMP/DMAc, NMP/DMF, DMAc/DMF, and NMP/DMAc/DMF), and the factors that influenced the phase inversion were discussed. Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and atomic force microscopy (AFM) were employed to characterize various membranes. Results indicated that PDA was coated on PVDF membrane surface and formed a smoother PDA layer. Water contact angle measurement confirmed the increased hydrophilicity of PDA modified membranes, but water flux decreased due to the adhesion of PDA on pore walls. The decrease of static adsorption of bovine serum albumin (BSA), the increase of flux recovery ratio (FRR), and the decline of fouling resistance for PDA modified membranes demonstrated that their antifouling properties have been improved significantly. The membrane prepared with NMP/DMAc displayed the highest decay rate of contact angle (16.6 ± 1.27%), the higher water flux (1358.5 ± 33.87 L m−2 h−1), the highest decrease of BSA adsorption (129.3 ± 5.02 μg cm−2), the highest increase rate of BSA rejection (13.6 ± 0.42%), and the highest FRR (92.8 ± 1.42%). This indicated that NMP/DMAc membrane possessed the most suitable structure to improve membrane performances by PDA coating. [ABSTRACT FROM AUTHOR]

Francois’ langur (Trachypithecus francoisi) is an endangered primate and endemic to the limestone forests of the tropical and subtropical zone of northern Vietnam and South-west China with a population of about 2,000 individuals. Conservation efforts are hampered by limited knowledge of habitat preference in its main distribution area. We surveyed the distribution of Francois’ langur and modeled the relationship between the probability of use and habitat features in Mayanghe National Nature Reserve, Guizhou, China. The main objectives of this study were to provide quantitative information on habitat preference, estimating the availability of suitable habitat, and providing management guidelines for the effective conservation of this species. By comparing 92 used locations with habitat available in the reserve, we found that Francois’ langur was mainly distributed along valleys and proportionally, used bamboo forests and mixed conifer-broadleaf forests more than their availability, whereas they tended to avoid shrubby areas and coniferous forests. The langur tended to occur at sites with lower elevation, steeper slope, higher tree canopy density, and a close distance to roads and water. The habitat occupancy probability was best modeled by vegetation type, vegetation coverage, elevation, slope degree, distances to nearest water, paved road, and farmland edge. The suitable habitat in this reserve concentrated in valleys and accounted for about 25% of the total reserve area. Our results showed that Francois’ langur was not only restricted at the landscapes level at the regions with karst topography, limestone cliffs, and caves, but it also showed habitat preference at the local scale. Therefore, the protection and restoration of the langur preferred habitats such as mixed conifer-broadleaf forests are important and urgent for the conservation of this declining species. [ABSTRACT FROM AUTHOR]

Francois’ langur (Trachypithecus francoisi) is an endangered primate and endemic to the limestone forests of the tropical and subtropical zone of northern Vietnam and South-west China with a population of about 2,000 individuals. Conservation efforts are hampered by limited knowledge of habitat preference in its main distribution area. We surveyed the distribution of Francois’ langur and modeled the relationship between the probability of use and habitat features in Mayanghe National Nature Reserve, Guizhou, China. The main objectives of this study were to provide quantitative information on habitat preference, estimating the availability of suitable habitat, and providing management guidelines for the effective conservation of this species. By comparing 92 used locations with habitat available in the reserve, we found that Francois’ langur was mainly distributed along valleys and proportionally, used bamboo forests and mixed conifer-broadleaf forests more than their availability, whereas they tended to avoid shrubby areas and coniferous forests. The langur tended to occur at sites with lower elevation, steeper slope, higher tree canopy density, and a close distance to roads and water. The habitat occupancy probability was best modeled by vegetation type, vegetation coverage, elevation, slope degree, distances to nearest water, paved road, and farmland edge. The suitable habitat in this reserve concentrated in valleys and accounted for about 25% of the total reserve area. Our results showed that Francois’ langur was not only restricted at the landscapes level at the regions with karst topography, limestone cliffs, and caves, but it also showed habitat preference at the local scale. Therefore, the protection and restoration of the langur preferred habitats such as mixed conifer-broadleaf forests are important and urgent for the conservation of this declining species. [ABSTRACT FROM AUTHOR]

Objective: Retinal prosthesis devices have shown great value in restoring some sight for individuals with profoundly impaired vision, but the visual acuity and visual field provided by prostheses greatly limit recipients' visual experience. In this paper, we employ computer vision approaches to seek to expand the perceptible visual field in patients implanted potentially with a high-density retinal prosthesis while maintaining visual acuity as much as possible., Approach: We propose an optimized content-aware image retargeting method, by introducing salient object detection based on color and intensity-difference contrast, aiming to remap important information of a scene into a small visual field and preserve their original scale as much as possible. It may improve prosthetic recipients' perceived visual field and aid in performing some visual tasks (e.g. object detection and object recognition). To verify our method, psychophysical experiments, detecting object number and recognizing objects, are conducted under simulated prosthetic vision. As control, we use three other image retargeting techniques, including Cropping, Scaling, and seam-assisted shrinkability., Main Results: Results show that our method outperforms in preserving more key features and has significantly higher recognition accuracy in comparison with other three image retargeting methods under the condition of small visual field and low-resolution., Significance: The proposed method is beneficial to expand the perceived visual field of prosthesis recipients and improve their object detection and recognition performance. It suggests that our method may provide an effective option for image processing module in future high-density retinal implants.

Objective: To compare the shaping quality in curved canals of two single-file technique systems with other two traditional full-sequential systems., Methods: Eighty mature molar canals with the curvature between 20 and 45 degrees were randomly divided into four groups. Specimens in each group were prepared to size 25 at working length using A (Reciproc), B (OneShape), C (MTwo) and D (Revo S), respectively. Each canal was scanned by micro-computed tomography before and after preparation. Parameters including changes in dentine volume, percentage of uninstrumented area, degree and tendency of transportation were analyzed. The operating time was also recorded., Results: In full canal length, there was no difference in canal dentine removal, instrumented percentage and transportation degree among four groups (P > 0.05). In the apical 4 mm region, group A removed more dentine [(2.14±0.76) mm(2) of canal surface area and (0.38 ± 0.15) mm(3) of canal volume] than groups B and C(P < 0.05). At 1 mm level, median of transportation degree of group A was 0.05 (0.03)mm, which was smaller than other groups (P < 0.05). Groups A and B took (86.3±24.6) s and (85.9±21.3) s, while groups C and D took (147.4±28.3) s and (126.3±27.7) s srespectively to finish preparation. Single file techniques were significantly faster than the two full-sequential systems (P < 0.01)., Conclusions: Compared with the continuous rotary systems, the reciprocating single-file system A showed better apical shaping ability. Both single-file techniques were more efficient than full-sequential systems for curved canal preparation. Single-file techniques appear to be the effective and efficient method for curved canal preparation.