Recently, smart polymer vesicles have attracted increasing interest due to their endless potential applications such as tunable delivery vehicles for the treatment of degenerative diseases. However, the evolution of stimuli-responsive vesicles from bench to bedside still seems far away for the limitations of current stimuli forms such as temperature, light, redox, etc. Since ultrasound combined with chemotherapy has been widely used in tumor treatment and the pH in tumor tissues is relatively low, we designed herein a novel polymer vesicle that respond to both physical (ultrasound) and chemical (pH) stimuli based on a PEO-b-P(DEA-stat-TMA) block copolymer, where PEO is short for poly(ethylene oxide), DEA for 2-(diethylamino)ethyl methacrylate and TMA for (2-tetrahydrofuranyloxy)ethyl methacrylate. These dually responsive vesicles show noncytotoxicity below 250 μg/mL and can encapsulate anticancer drugs, exhibiting retarded release profile and controllable release rate when subjected to ultrasound radiation or varying pH in tris buffer at 37°C.

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Nematic order is the breaking of rotational symmetry in the presence of translational invariance. While originally defined in the context of liquid crystals, the concept of nematic order has arisen in crystalline matter with discrete rotational symmetry, most prominently in the tetragonal Fe-based superconductors where the parent state is four-fold symmetric. In this case the nematic director takes on only two directions, and the order parameter in such "Ising-nematic" systems is a simple scalar. Here, using a novel spatially-resolved optical polarimetry technique, we show that a qualitatively distinct nematic state arises in the triangular lattice antiferromagnet Fe1/3NbS2. The crucial difference is that the nematic order on the triangular lattice is a ℤ " , or three-state Potts-nematic order parameter. As a consequence, the anisotropy axes of response functions such as the resistivity tensor can be continuously re-oriented by external perturbations.This discovery provides insight into realizing devices that exploit analogies with nematic liquid crystals.

TiO2 nanoparticle has been considered as a safe sunscreen agent to reduce the skin cancer risk when exposed to sunlight. However, recently it was found that TiO2 particles accelerate the photodamage of skin due to their photocatalytic degradation activity. To effectively eradicate this unwanted effect, we present a new strategy toward the preparation of organic/inorganic hybrid polymer/TiO2 nanoparticles with highly effective UV-screening property but eliminated photocatalytic activity. We prepared new polymer micelles with corona–shell–core structure based on self-assembly of poly(ethylene oxide)-block-poly(2-(dimethylamino)ethyl methacrylate)-block-poly(styrene) (PEO-b-PDMA-b-PS) triblock copolymer. Selective deposition of hydrophobic tetrabutyl titanate (TBT) in the PDMA shell in polar solvent leads to a thin PDMA/TiO2 hybrid layer (∼8 nm), which can not only effectively reflect UV rays but also eliminate its photocatalytic ability to protect skin. The sol–gel reactions of TBTs in the PS core domain lead to a PS/TiO2 hybrid core, which can also absorb/reflect UV lights by PS/TiO2. The biocompatible PEO coronas can prevent direct contact of TiO2 with skin. Moreover, sol–gel reactions in the PDMA and PS domains can stabilize the triblock copolymer micelles, which offer the promising potential for further formulations in aqueous solution. The ATRP kinetics confirmed that PEO-b-PDMA-b-PS triblock copolymer can be synthesized in one pot, which simplified the synthetic procedure of copolymers. TEM and DLS studies revealed the morphology and size of self-assembled polymer micelles and the subsequent polymer/TiO2 hybrid nanoparticles upon sol–gel reactions. UV experiments confirmed the highly efficient UV screening activity but eliminated photocatalytic property of polymer/TiO2 hybrid nanoparticles. For example, at extremely low TiO2 content in solution (10 ppm of polymer/TiO2 solid), ∼70% UV radiation can be blocked compared to pure organic polymer micelle, which is also much more efficient than commercially available TiO2 nanoparticles (P25). UV and DLS studies confirmed the ultrahigh stability of polymer/TiO2 hybrid nanoparticles upon strong UV radiation, which is suitable for long-term applications. Nitrogen adsorption/desorption experiment revealed that the ultralow surface area of TiO2 nanoparticles (1.6 m2 g–1) is consistent with their extremely poor photocatalytic performance.

Background In rural areas of China, hypertension is on the rise and it is drawing the Chinese government’s attention. The health outcomes of hypertension management can be positively impacted by patient satisfaction with primary care physicians (PCPs), and the influence of patient trust on satisfaction cannot be ignored. This study aimed to analyze the effect of trust in PCPs on patient satisfaction among patients with hypertension in rural China, and the influence of patients’ socio-demographic characteristics and hypertension-management-related factors. Methods A multi-stage stratified random sampling method was adopted to investigate 2665 patients with hypertension in rural China. Patient trust and satisfaction were measured using the Chinese version of the Wake Forest Physician Trust Scale and the European Task Force on Patient Evaluation of General Practice. Multiple linear regression was used to analyze the factors influencing patient satisfaction, and structural equation modeling was conducted to clarify the relationships among patient trust and patient satisfaction with PCPs. Results Patients’ trust in their PCPs’ benevolence had a positive main effect on all three satisfaction dimensions (clinical behavior: β = 0.940, p <  0.01; continuity and cooperation: β = 0.910, p <  0.01; and organization of care: β = 0.879, p <  0.01). Patients’ trust in their PCPs’ technical competence had a small negative effect on all three satisfaction dimensions (clinical behavior: β = − 0.077, p <  0.01; continuity and cooperation: β = − 0.136, p <  0.01; and organization of care: β = − 0.064, p <  0.01). Patient satisfaction was also associated with region, gender, insurance status, distance from the nearest medical/health-service institution, and number of visits to PCPs in the past year. Conclusions Patients focused more on physicians’ benevolence than on their technical competence. Hence, medical humanities and communication skills education should be emphasized for PCPs. Regarding region-based and health-insurance-based differences, the inequities between eastern, central, and western provinces, as well as between urban and rural areas, must also be addressed.

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