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DAL-1/4.1B is frequently absent in lung cancer tissues, which is significantly related to the occurrence and development of lung cancer. In this research, we found that DAL-1/4.1B affected the uptake of exosomes by lung cancer cells. When the expression of DAL-1/4.1B increased and decreased, the ability of exosome uptake enhanced and attenuated correspondingly. And we found that when cells were treated with different vesicles uptake inhibitors (chlorpromazine, methyl-β-cyclodextrin (MβCD), cytochalasin D, chloroquine and heparin) and heparinase (HSPE), only heparin and HSPE counteracted the uptake enhancement effect caused by DAL-1/4.1B. Therefore, we speculated that DAL-1/4.1B might promote the uptake of exosomes through the heparan sulfate proteoglycans (HSPGs) pathway. After screening the expression of HSPGs and HSPE in H292 cells, the expression of heparan sulfate proteoglycan 2 (HSPG2) increased with overexpression of DAL-1/4.1B and decreased with knockdown of DAL-1/4.1B. Meanwhile, exosome uptake decreased with HSPG2 knockdown in H292 and DAL-1/4.1B-overexpressing H292 cells. Moreover, knockdown of DAL-1/4.1B and HSPG2 in lung cancer A549 cells resulted in a similar decrease in exosome uptake, and the expression of HSPG2 was also decreased with DAL-1/4.1B knockdown. These results indicated that HSPG2 directly affected the uptake of exosomes, while DAL-1/4.1B positively affected the expression of HSPG2. Therefore, DAL-1/4.1B may promote cellular adhesion and inhibit migration in cancer cells.

A new type of deacetylated cellulose acetate (DA)@polydopamine (PDA) composite nanofiber membrane was fabricated by electrospinning and surface modification. The membrane was applied as a highly efficient adsorbent for removing methylene blue (MB) from an aqueous solution. The morphology, surface chemistry, surface wettability, and effects of operating conditions on MB adsorption ability, as well as the equilibrium, kinetics, thermodynamics, and mechanism of adsorption, were systematically studied. The results demonstrated that a uniform PDA coating layer was successfully developed on the surface of DA nanofibers. The adsorption capacity of the DA@PDA nanofiber membrane reached up to 88.2 mg/g at a temperature of 25 °C and a pH of 6.5 after adsorption for 30 h, which is about 8.6 times higher than that of DA nanofibers. The experimental results showed that the adsorption behavior of DA@PDA composite nanofibers followed the Weber's intraparticle diffusion model, pseudo-second-order model, and Langmuir isothermal model. A thermodynamic analysis indicated that endothermic, spontaneous, and physisorption processes occurred. Based on the experimental results, the adsorption mechanism of DA@PDA composite nanofibers was also demonstrated.

Hydrogen, a clean and renewable energy carrier, is a promising alternative energy resource to replace fossil fuels. Among various hydrogen production methods, water electrolysis is a sustainable approach to gain pure hydrogen in useful amounts, but its use is still limited by the lack of efficient and low-cost electrocatalysts. Here, a convenient and straightforward mechanical alloying (MA) process is reported that can be used to produce heterostructured catalysts with good performance for the hydrogen evolution reaction (HER). A NiTiO3/Ni hybrid was reconstructed, which was always considered to be an average HER catalyst, via the ball milling of TiO2 with Ni powder in a vacuum. The resulting material exhibits an ultra-low overpotential of ∼10 mV at 10 mA cm−2 (η10) with a Tafel slope of ∼31 mV dec−1, and maintains its stability after running for 200 h in 1 M KOH. In addition, catalysts produced by directly ball milling NiTiO3 with Ni, Co, or Fe powder also delivered high performance with η10 values of ∼13 mV, 27 mV, and 50 mV, respectively. The enhanced properties are attributed to the introduction of oxygen vacancies into NiTiO3 and the heterostructures produced via MA, which fully utilize the potential of NiTiO3 to accelerate water dissociation for the HER in basic media. Because MA is a mature industrial technique, this approach is promising for large-scale applications. The versatile strategy might also benefit and promote the exploration of catalysts for use in other important electrocatalytic fields.

We revisit the problem of computing an optimal partial cover of points by intervals. We show that the greedy algorithm computes a permutation $\Pi = \pi_1, \pi_2,\ldots$ of the intervals that is $3/4$-competitive for any prefix of $k$ intervals. That is, for any $k$, the intervals $\pi_1 \cup \cdots \cup \pi_k$ covers at least $3/4$-fraction of the points covered by the optimal solution using $k$ intervals. We also provide an approximation algorithm that, in $O(n + m/\varepsilon)$ time, computes a cover by $(1+\varepsilon)k$ intervals that is as good as the optimal solution using $k$ intervals, where $n$ is the number of input points, and $m$ is the number of intervals (we assume here the input is presorted). Finally, we show a counter example illustrating that the optimal solutions for set cover do not have the diminishing return property -- that is, the marginal benefit from using more sets is not monotonically decreasing. Fortunately, the diminishing returns does hold for intervals.

Along with increasing oily, industrial wastewater and seawater pollution, oil spills—and their clean-up via the separation of oil and water—are still a worldwide challenge. Aiming to fabricate an oil/water separation membrane with excellent comprehensive performance, we report here a new type of multifunctional deacetylated cellulose acetate (d-CA) membrane. The cellulose acetate (CA) nanofiber membranes are fabricated by electrospinning and then deacetylated to obtain the d-CA nanofiber membranes, which are super-amphiphilic in air, oleophobic in water, and super-hydrophilic in oil. The multifunctional d-CA nanofiber membranes can be used as water-removal substances for oil/water mixtures, as well as emulsified oil/water and oil/corrosive aqueous systems, with gravity as the only needed driving force. The d-CA nanofiber membranes possess the highest separation flux, reaching up to 38,000 L/m2·h, and the highest separation efficiency, reaching up to 99.97 % for chloroform/water mixtures under the force of gravity. In fact, the separation flux was several times higher than that of commercial CA (c-CA) membranes. The excellent anti-pollution and self-cleaning abilities endow the membranes with powerful cyclic stability and reusability. The d-CA nanofiber membranes show great application prospects in chemical plants, textile mills, and the food industry, as well as offshore oil spills, to separate oil from water.

A new, all room-temperature solution process is developed to fabricate efficient, low-cost, and stable perovskite solar cells (PVSCs). The PVSCs show high efficiency of 17.10% and 14.19%, with no hysteresis on rigid and flexible substrates, respectively, which are the best efficiencies reported to date for PVSCs fabricated by roomtemperature solution-processed techniques. The flexible PVSCs show a remarkable power-per-weight of 23.26 W g(-1). [GRAPHICS] .