Associations of Various Physical Activities with Mortality and Life Expectancy are Mediated by Telomere Length.

OBJECTIVES: Physical activity (PA) and telomeres both contribute to healthy aging and longevity. To investigate the optimal dosage of various PA for longevity and the role of telomere length in PA and mortality. DESIGN: Prospective cohort study. SETTING AND PARTICIPANTS: A total of 333,865 adults (mean age of 56 years) from the UK Biobank were analyzed. METHODS: Walking, moderate PA (MPA), and vigorous PA (VPA) were self-reported via questionnaire, and leukocyte telomere length (LTL) was measured. Cox proportional hazards regression was used to predict all-cause mortality risk. A flexible parametric Royston-Parmar survival model was used to estimate life expectancy. RESULTS: During a median follow-up of 13.8 years, 19,789 deaths were recorded. Compared with the no-walking group, 90 to 720 minutes/week of walking was similarly associated with 27% to 31% of lower mortality and about 6 years of additional life expectancy. We observed nearly major benefits for mortality and life expectancy among those meeting the PA guidelines [151-300 minutes/wk for MPA: hazard ratio (HR) 0.80, 95% CI 0.75-0.85, 3.40-3.42 additional life years; 76-150 minutes/wk for VPA: HR 0.78, 95% CI 0.75-0.82, 2.61 years (2.33-2.89)] vs the no-PA group. Similar benefits were also observed at 76-150 and 301-375 minutes/wk of MPA (18%-19% lower mortality, 3.20-3.42 gained years) or 151-300 minutes/wk of VPA (20%-26% lower mortality, 2.41-2.61 gained years). The associations between MPA, VPA, and mortality risk were slightly mediated by LTL (≈1% mediation proportion, both P < .001). CONCLUSIONS AND IMPLICATIONS: Our study suggests a more flexible range of PA than the current PA guidelines, which could gain similar benefits and is easier to achieve: 90 to 720 minutes/wk of walking, 75 to 375 minutes/wk of MPA, and 75 to 300 minutes/wk of VPA. Telomeres might be a potential mechanism by which PA promotes longevity.

Composite polymer electrolytes with ionic liquid grafted-Laponite for dendrite-free all-solid-state lithium metal batteries.

Composite polymer electrolytes (CPEs) with high ionic conductivity and favorable electrolyte/electrode interfacial compatibility are promising alternatives to liquid electrolytes. However, severe parasitic reactions in the Li/electrolyte interface and the air-unstable inorganic fillers have hindered their industrial applications. Herein, surface-edge opposite charged Laponite (LAP) multilayer particles with high air stability were grafted with imidazole ionic liquid (IL-TFSI) to enhance the thermal, mechanical, and electrochemical performances of polyethylene oxide (PEO)-based CPEs. The electrostatic repulsion between multilayers of LAP-IL-TFSI enables them to be easily penetrated by PEO segments, resulting in a pronounced amorphous region in the PEO matrix. Therefore, the CPE-0.2LAP-IL-TFSI exhibits a high ionic conductivity of 1.5 × 10-3 S cm-1 and a high lithium-ion transference number of 0.53. Moreover, LAP-IL-TFSI ameliorates the chemistry of the solid electrolyte interphase, significantly suppressing the growth of lithium dendrites and extending the cycling life of symmetric Li cells to over 1000 h. As a result, the LiFePO4||CPE-0.2LAP-IL-TFSI||Li cell delivers an outstanding capacity retention of 80% after 500 cycles at 2C at 60 °C. CPE-LAP-IL-TFSI also shows good compatibility with high-voltage LiNi0.8Co0.1Mn0.1O2 cathodes.

Laponite-Supported Gel Polymer Electrolyte with Multiple Lithium-Ion Transport Channels for Stable Lithium Metal Batteries.

Lithium metal batteries have emerged as a promising candidate for next-generation power systems. However, the high reactivity of lithium metal with liquid electrolytes has resulted in decreased battery safety and stability, which poses a significant challenge. Herein, we present a modified laponite-supported gel polymer electrolyte (LAP@PDOL GPE) that was fabricated using in situ polymerization initiated by a redox-initiating system at ambient temperature. The LAP@PDOL GPE effectively facilitates the dissociation of lithium salts via electrostatic interaction and simultaneously constructs multiple lithium-ion transport channels within the gel polymer network. This hierarchical GPE demonstrates a remarkable ionic conductivity of 5.16 × 10-4 S cm-1 at 30 °C. Furthermore, the robust laponite component of the LAP@PDOL GPE forms a barrier against Li dendrite growth while also participating in the establishment of a stable electrode/electrolyte interface with Si-rich components. The in situ polymerization process further improves the interfacial contact, enabling the LiFePO4/LAP@PDOL GPE/Li cell to exhibit an impressive capacity of 137 mAh g-1 at 1C, with a capacity retention of 98.5% even after 400 cycles. In summary, the developed LAP@PDOL GPE shows great potential in addressing the critical issues of safety and stability associated with lithium metal batteries while also delivering improved electrochemical performance.

In situ Interweaved Binder Framework Mitigating the Structural and Interphasial Degradations of High-nickel Cathodes in Lithium-ion Batteries.

The practical viability of high-nickel layered oxide cathodes is compromised by the interphasial and structural degradations. Herein, we demonstrate that by applying an in situ interweaved binder, the cycling stability of high-nickel cathodes can be significantly improved. Specifically, the results show that the resilient binder network immobilizes the transition-metal ions, suppresses electrolyte oxidative decomposition, and mitigates cathode particles pulverization, thus resulting in suppressed cathode-to-anode chemical crossover and ameliorated chemistry and architecture of electrode-electrolyte interphases. Pouch full cells with high-mass-loading LiNi0.8 Mn0.1 Co0.1 O2 cathodes achieve 0.02 % capacity decay per cycle at 1 C rate over 1 000 deep cycles at 4.4 V (vs. graphite). This work demonstrates a rational structural and compositional design strategy of polymer binders to mitigate the structural and interphasial degradations of high-Ni cathodes in lithium-ion batteries.

Bifunctional Solid-State Copolymer Electrolyte with Stabilized Interphase for High-Performance Lithium Metal Battery in a Wide Temperature Range.

Solid-state polymer electrolytes (SPEs) are expected to guarantee safe and durable operations of lithium metal batteries (LMBs). Herein, inspired by the salutary poly(vinyl ethylene carbonate) (PVEC) component in the solid electrolyte interphase, cross-linking vinyl ethylene carbonate and ionic liquid copolymers were synthesized by in-situ polymerization to serve as polymer electrolyte for LMBs. On one hand, due to rich ester bonds of PVEC, Li+ could transfer by coupling/decoupling with oxygen atoms. On the other hand, the imidazole ring of ionic liquid could facilitate the dissociation of lithium salt to promote the free movement of Li+ . The bifunctional component synergistically increased the ionic conductivity of the SPE to 1.97×10-4  S cm-1 at 25 °C. Meanwhile, it also showed a wide electrochemical window, superior mechanical properties, outstanding non-combustibility, and excellent interfacial compatibility. The bifunctional copolymer-based LiFePO4 batteries could normally operate at 0 to 60 °C, making them a promising candidate for wide-temperature-rang LMBs.

Dual Cross-Linked Fluorinated Binder Network for High-Performance Silicon and Silicon Oxide Based Anodes in Lithium-Ion Batteries.

In next generation lithium-ion batteries (LIBs), silicon is a promising electrode material due to its surprisingly high specific capacity, but it suffers from serious volume changes during the lithiation/delithiation process which gradually lead to the destruction of the electrode structure. A novel fluorinated copolymer with three different polar groups was synthesized to overcome this problem: carboxylic acid, amide, and fluorinated groups on a single polymer backbone. Moreover, a dual cross-linked network binder was prepared by thermal polymerization of the fluorinated copolymer and sodium alginate. Unlike the common chemical cross-linked network with a gradual and nonreversible fracturing, the dual cross-linked network which combines chemical and physical cross-linking could effectively hold the silicon particles during the volume change process. As a result, excellent electrochemical performance (1557 mAh g-1 at a 4 A g-1 current density after 200 cycles) was achieved with this novel reversible cross-linked binder. Further research studies with regard to the influences of fluorine and acrylamide content were conducted to systematically evaluate the designed binder. Moreover, with the help of new binder, the silicon/graphite and silicon oxide/graphite electrode exhibit superb cycle performance with capacity fade rate of 0.1% and 0.025% per cycle over 200 and 700 cycles, respectively. This novel and unsophisticated design gives a result for fabrication of high-performance Si based electrodes and advancement of the realization of practical application.

Highly Stable Amphiphilic Organogel with Exceptional Anti-icing Performance.

Various organogel materials with either a liquid or solid surface layer have recently been designed and prepared. In this work, amphiphilic organogels (AmOG) are innovatively developed from copolymer P(PDMS-r-PEG-r-GMA) and 2,2'-diaminodiphenyldisulfide via epoxy group addition reaction and then infiltrated with amphiphilic lubricants instead of traditional hydrophilic or hydrophobic lubricants. Because of synergistic effects of hydrophilic and hydrophobic segments of amphiphilic lubricants, the AmOG surfaces showed high stability and excellent anti-icing performance. The delay in the freezing point of water was 1000 s on AmOG surfaces, which is 40 times longer as compared to the untreated hydrophilic glass surface. More importantly, low ice adhesion strength (15.1 kPa) was observed on AmOG which remained about 40 kPa even after 20 icing-deicing cycles. The novel amphiphilic organogels provide a new idea to prepare long-term anti-icing materials for practical applications.

Silicone Oil Swelling Slippery Surfaces Based on Mussel-Inspired Magnetic Nanoparticles with Multiple Self-Healing Mechanisms.

In this work, a novel substrate building block, magnetic Fe3O4 nanoparticles armed with dopamine molecules were developed via mussel-inspired metal-coordination bonds. Combined with glycidyl methacrylate, polydimethylsiloxane propyl ether methacrylate, and diethylenetriamine, the original silicone oil swelling slippery liquid-infused porous surfaces (SLIPS) were first prepared by reversible coordinate bonds and strong covalent bonds cross-linking process. The matrix mechanical characteristics and surface physicochemical properties were systematically investigated. Results showed that the mechanical property of copolymer matrix and surface wettability of SLIPS can be remarkably recovered, which were due to the synergistic interactions of magnetic nanoparticles' intrinsic photothermal effect, reversible Fe-catechol coordination, and diffused lubricating liquid. After irradiating with sunlamp for 2 h and sequentially healing for 10 h under ambient conditions, the crack almost disappeared under optical microscopy with 78.25% healing efficiency (HEf) of toughness, and surface slippery was completely retrieved to water droplets. The efficient self-heal of copolymer matrix (66.5% HEf after eighth cutting-healing cycle) and recovering of slipperiness (SA < 5° and 5° < SA < 17° after fourth and eighth cutting-centrifuging-healing cycles, respectively) would extend longevity of SLIPS when subjected to multiple damages. Moreover, the prepared SLIPS displayed superb self-cleaning and liquid-repellent properties to a wide range of particulate contaminants and fluids.

pH-Induced Switchable Superwettability of Efficient Antibacterial Fabrics for Durable Selective Oil/Water Separation.

The superhydrophobic antibacterial fabrics with intelligent switchable wettability were fabricated by the cross-link reaction among pH-responsive antibacterial copolymer tethered hydroxyl groups, methylol-contained poly(ureaformaldehyde) nanoparticles (PUF NPs), and hexamethylene diisocyanate. It was found that the surface concentration of N+ were heavily influenced by acid solutions, resulting in the rapid wettability conversion from superhydrophobicity/superoleophilicity to superhydrophilicity/underwater superoleophobicity in a remarkably short time. The above responsiveness feature of coated cotton fabric contributes a prominent selective oil/water separation property, and the separation efficiency invariably remained at greater than 95% even after 20 reuse cycles, which exhibited brilliant durability. More importantly, the coated cotton fabric possessed excellent self-cleaning performance after contamination by oil and held high bactericidal rate (more than 80%) regardless of pH treatment, and thus could abate the surface biological pollution caused by bacteria proliferation. The attractive properties of the prepared smart superwetting materials shows great promise for potential application in oil/water separation from an environmental-protection perspective.

China and the United States--Global partners, competitors and collaborators in nanotechnology development.

USA and China are two leading countries engaged in nanotechnology research and development. They compete with each other for fruits in this innovative area in a parallel and compatible manner. Understanding the status and developmental prospects of nanotechnology in USA and China is important for policy-makers to decide nanotechnology priorities and funding, and to explore new ways for global cooperation on key issues. We here present the nanoscience and nanomedicine research and the related productivity measured by publications, and patent applications, governmental funding, policies and regulations, institutional translational research, industrial and enterprise growth in nanotechnology-related fields across China and USA. The comparison reveals some marked asymmetries of nanotechnology development in China and USA, which may be helpful for future directions to strengthen nanotechnology collaboration for both countries, and for the world as a whole.

Dendrimeric anticancer prodrugs for targeted delivery of ursolic acid to folate receptor-expressing cancer cells: synthesis and biological evaluation.

The anticancer efficacy of ursolic acid (UA) was limited by poor water solubility, non-specific tumor distribution, and low bioavailability. To overcome this problem, polyamidoamine (PAMAM) conjugated with UA and folic acid (FA) as novel dendrimeric prodrugs were designed and successfully synthesized by a concise one-pot synthetic approach. Both FA and UA were covalently conjugated to the surface of PAMAM through acid-labile ester bonds and the covalently linked UA could be hydrolysed either in acidic (pH 5.4) or in neutral (pH 7.4) PBS solution. The cellular uptake study indicated that the presence of FA enhanced uptake of the dendrimeric prodrugs in folate receptor (FR) over-expressing Hela cells. The enhanced cellular uptake could be due to the electrostatic absorptive endocytosis and FR-mediated endocytosis. In contrast, for HepG2 cells, a FR-negative cell line, FA conjugation on the surface of the dendrimer showed no effect on the cellular uptake. In MTT assay and cell cycle analysis, FA-modified dendrimeric prodrugs showed significantly enhanced toxicity than non-FA-modified ones in Hela cells. These results suggested that FA-modified dendrimeric UA prodrugs have the potential for targeted delivery of UA into cancer cells to improve its anti-tumor efficacy.