Oral health with the 65 age group within Israel2020

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This work shows the great potential of the CNF as a nanofluidic platform and the photothermal enhancement in osmotic energy conversion, and the ultralow loading design provides a practical and economical way to fully utilize other energy resources for enhancing osmotic energy conversion.To address the challenge of the airborne transmission of SARS-CoV-2, photosensitized electrospun nanofibrous membranes were fabricated to effectively capture and inactivate coronavirus aerosols. With an ultrafine fiber diameter (∼200 nm) and a small pore size (∼1.5 μm), optimized membranes caught 99.2% of the aerosols of the murine hepatitis virus A59 (MHV-A59), a coronavirus surrogate for SARS-CoV-2. In addition, rose bengal was used as the photosensitizer for membranes because of its excellent reactivity in generating virucidal singlet oxygen, and the membranes rapidly inactivated 97.1% of MHV-A59 in virus-laden droplets only after 15 min irradiation of simulated reading light. Singlet oxygen damaged the virus genome and impaired virus binding to host cells, which elucidated the mechanism of disinfection at a molecular level. Membrane robustness was also evaluated, and in general, the performance of virus filtration and disinfection was maintained in artificial saliva and for long-term use. Only sunlight exposure photobleached membranes, reduced singlet oxygen production, and compromised the performance of virus disinfection. selleck compound In summary, photosensitized electrospun nanofibrous membranes have been developed to capture and kill airborne environmental pathogens under ambient conditions, and they hold promise for broad applications as personal protective equipment and indoor air filters.Type-II heterostructures (HSs) are essential components of modern electronic and optoelectronic devices. Earlier studies have found that in type-II transition metal dichalcogenide (TMD) HSs, the dominating carrier relaxation pathway is the interlayer charge transfer (CT) mechanism. Here, this report shows that, in a type-II HS formed between monolayers of MoSe2 and ReS2, nonradiative energy transfer (ET) from higher to lower work function material (ReS2 to MoSe2) dominates over the traditional CT process with and without a charge-blocking interlayer. Without a charge-blocking interlayer, the HS area shows 3.6 times MoSe2 photoluminescence (PL) enhancement as compared to the MoSe2 area alone. In a completely encapsulated sample, the HS PL emission further increases by a factor of 6.4. After completely blocking the CT process, more than 1 order of magnitude higher MoSe2 PL emission was achieved from the HS area. This work reveals that the nature of this ET is truly a resonant effect by showing that in a similar type-II HS formed by ReS2 and WSe2, CT dominates over ET, resulting in a severely quenched WSe2 PL. This study not only provides significant insight into the competing interlayer processes but also shows an innovative way to increase the PL emission intensity of the desired TMD material using the ET process by carefully choosing the right material combination for HS.A polymer actuator typically responds to only one or two types of stimuli, where sensing and actuation are simultaneously exerted by the same responsive polymer. In cells, sensing and actuation are exerted separately by different biomolecules, which are integrated into nanoscale assemblies to construct the signaling network, making cells a multistimuli responsive and multimodal system. Inspired by the structure-function relationship of the signaling network in cells, we have developed a strategy to select and assemble proper functional polymers into assemblies, where sensing and actuation are exerted by different polymers, and the assemblies can present novel functions beyond that of each polymer component. Three polymers [polyaniline, PANi; poly(N-isopropylacrylamide), PNIPAm; and polydimethylsiloxane, PDMS] are integrated as nodes into a simple energy transduction network, which can be regulated by three molecular factors (pH, kosmotropic anions, and polyethylene glycol). PANi converts the light or electric stimulus into heat, which triggers the actuation of PNIPAm and PDMS. Relying on this energy transduction network, the polymer assembly can respond to six types of stimuli (light, electricity, temperature, water, ions, and organic solvents) and perform different actuation modes, serving as a powerful actuator. Programmable complex deformation upon multiple simultaneous or sequential stimuli has also been achieved by this actuator. An adaptive gripper to catch thin objects and a self-regulating switch to maintain environmental humidity illustrate the wide potential of this actuator for next-generation smart materials and soft robots.Functional bionanocomposites have evoked immense research interests in many fields including biomedicine, food packaging, and environmental applications. Supramolecular self-assembled bionanocomposite materials fabricated by biopolymers and two-dimensional (2D) nanomaterials have particularly emerged as a compelling material due to their biodegradable nature, hierarchical structures, and designable multifunctions. However, construction of these materials with tunable properties has been still challenging. Here, we report a self-assembled, flexible, and antioxidative collagen nanocomposite film (CNF) via regulating supramolecular interactions of type I collagen and tannic acid (TA)-functionalized 2D synthetic clay nanoplatelets Laponite (LAP). Specifically, TA-coordinated LAP (LAP-TA) complexes were obtained via chelation and hydrogen bonding between TA and LAP clay nanoplatelets and further used to stabilize the triple-helical confirmation and fibrillar structure of the collagen via hydrogen bonding and electrostatic interactions, forming a hierarchical microstructure. The obtained transparent CNF not only exhibited the reinforced thermal stability, enzymatic resistance, tensile strength, and hydrophobicity but also good water vapor permeability and antioxidation. For example, the tensile strength was improved by over 2000%, and the antioxidant property was improved by 71%. Together with the simple fabrication process, we envision that the resulting CNF provides greater opportunities for versatile bionanocomposites design and fabrication serving as a promising candidate for emerging applications, especially food packaging and smart wearable devices.Human APOBEC3A (A3A) is a nucleic acid-modifying enzyme that belongs to the cytidine deaminase family. Canonically, A3A catalyzes the deamination of cytosine into uracil in single-stranded DNA, an activity that makes A3A both a critical antiviral defense factor and a useful tool for targeted genome editing. However, mutagenesis by A3A has also been readily detected in both cellular DNA and RNA, activities that have been implicated in cancer. Given the importance of substrate discrimination for the physiological, pathological, and biotechnological activities of A3A, here we explore the mechanistic basis for its preferential targeting of DNA over RNA. Using a chimeric substrate containing a target ribocytidine within an otherwise DNA backbone, we demonstrate that a single hydroxyl at the sugar of the target base acts as a major selectivity determinant for deamination. To assess the contribution of bases neighboring the target cytosine, we show that overall RNA deamination is greatly reduced relative to that of DNA but can be observed when ideal features are present, such as preferred sequence context and secondary structure. A strong dependence on idealized substrate features can also be observed with a mutant of A3A (eA3A, N57G), which has been employed for genome editing due to altered selectivity for DNA over RNA. Altogether, our work reveals a relationship between the overall decreased reactivity of A3A and increased substrate selectivity, and our results hold implications both for characterizing off-target mutagenesis and for engineering optimized DNA deaminases for base-editing technologies.Photodynamic therapy (PDT) and immunotherapy are considered promising methods for the treatment of tumors. However, these treatment systems are still suffering from shortcomings such as hypoxia, easy metastasis, and delayed immune response during PDT. Therefore, it is still challenging to establish a programmed and rapid response immune combination therapy platform. Here, we construct a two-step synergetic therapy platform for the treatment of primary tumors and distant tumors using upconversion nanoparticles (UCNPs) and engineered bacteria as therapeutic media. In the first step, erbium ion (Er3+)-doped UCNPs act as a photoswitcher to activate the photosensitizer ZnPc to produce 1O2 for primary tumor therapy. In the second step, thulium ion (Tm3+)-doped UCNPs can emit blue-violet light under the excitation of near-infrared (NIR) light to activate the engineered bacteria to produce interferon (INF-γ) and release them in the intestine, which can not only treat tumors directly but also act with PDT to regulate immune pathways to activate the immune system, resulting in a joint immunotherapy effect to inhibit the growth of distant tumors. As a new type of programmatic combination therapy, we have proved that this platform can jointly activate the body's immune system during PDT and immunization treatment and can effectively inhibit tumor metastasis.Stretchable electronics allow functional devices to integrate with human skin seamlessly in an emerging wearable platform termed epidermal electronics. Compliant conductors represent key building components for functional devices. Among the various candidates, gallium-based liquid metals stand out with metallic conductivity and inherent deformability. Currently, the widespread applications of liquid metals in epidermal electronics are hindered by the low steam permeability and hence unpleasant wearing perceptions. In this study, a facile physical deposition approach is established to create a liquid metal micromesh over an elastomer sponge, which exhibits low sheet resistance (∼0.5 Ω sq-1), high stretchability (400% strain), and excellent durability. The porous micromesh shows textile-level permeability to achieve long-term wearing comfort. The conformal interaction of the liquid metal micromesh with the skin gives rise to a low contact impedance. An integrated epidermal sensing sleeve is demonstrated as a human-machine interface to distinguish different hand gestures by recording muscle contractions. The reported stretchable and permeable liquid metal conductor shows promising potentials in next-generation epidermal electronics.A photoelectrochemical (PEC) electrode for glucose detection was built based on polyaniline (PANI) modified titanium dioxide heterojunction (FH-TiO2) structures. Ultrathin titanium dioxide (TiO2) nanosheets are assembled onto rutile nanorods (TiO2 NRs). Experiments show that the main exposed faces of these nanosheets are (101) or (111) crystal planes. Proven by theoretical calculation, the bottom of the conduction band (CB) of (111) is 0.15 eV lower than the bottom of the conduction band of (101). Therefore, when the material is excited by light, photogenerated electrons are able to transfer from the conduction band of (101) to the conduction band of (111). PANI was introduced as a medium to effectively conduct photogenerated charges between glucose oxidase and titanium dioxide. A photoelectric detection electrode for glucose was fabricated by loading glucose oxidase onto PANI@FH-TiO2. This electrode showed excellent performance in 0.2-1.0 mM linear range with a sensitivity 15.63 μA mM-1 cm-2 and 1.0-15.0 mM linear range with a sensitivity of 1.