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The membrane fouling triggered by biofouling layer is the critical factor limiting the application of biofiltration-facilitated gravity-driven membrane (GDM) system in decentralized drinking water treatment. Powdered activated carbon (PAC) and alumina (AA) were used to mitigate membrane fouling by pre-deposition. Pre-deposited PAC and AA improved the stable flux of the biofiltration-facilitated GDM systems, increasing by 9.6% and 17.0%, respectively. The removal of dissolved organic carbon, UV254 and protein-like material was sequentially enhanced by pre-deposition of PAC and AA, respectively. Pre-deposited AA performed better than pre-deposition of PAC in restricting the adhesion of soluble microbial products to the membrane. After pre-deposition of PAC and AA, the porosities of the biofouling layers increased by 0.78% and 2.51%, and the protein/polysaccharide ratio in extracellular polymeric substances (EPS) decreased from 111.8% to 53.4% and 39.8%, respectively. The protein in tightly bound EPS showed a significant positive (p < 0.05) relationship with the total membrane resistance and genus Acidovorax. Zoogloea was the core genus among the bacterial communities related to EPS production. Overall, pre-deposition of PAC and AA can be a simple and effective strategy to alleviate membrane fouling in biofiltration-facilitated GDM.

Using excellent kinetic transport graphitized carbon nanofibers network to construct free-standing V2O5-based electrode is an effective approach to develop high-performance lithium ion batteries. Herein, we successfully prepare graphitized carbon nanofibers by combining the electrospinning and the catalytic effect of iron oxide, and the conductance of graphitized carbon nanofibers is increased by 5 × 10 4 times compared to the amorphous carbon. Through hydrothermal method, the V2O5 nanosheets can be anchored on the surface of graphitized carbon nanofibers, forming a flexible and free-standing composite electrode, which can be directly used as cathode electrodes with a reversible capacity of 290 mAh g−1 at 0.1 C and a capacity higher than 105 mAh g−1 even at a large current density of 20 C, retaining a capacity of 160 mAh g−1 at 5.0 C even over 700 cycles. This is the first report to synthesize V2O5 nanosheets on graphitized carbon nanofibers prepared by electrospinning to construct a free-standing composite electrode with high rate capability and cycling stability lithium ion storage performances.

Expected to be the next generation separation membranes, graphene-based functional membranes are springing up in the domains of water desalination and purification. Considering the relatively large interlayer spacing and the swelling effect of the pure GO membranes in solution, feasible strategies must be adopted to overcome these obstacles. Based on the electrostatic attraction between GO and protonated g-C3N4, uniform and compact GO/g-C3N4 hybrid membranes are firstly prepared by a vacuum filtration method and then rGO/g-C3N4 hybrid membranes are fabricated under mild UV irradiation. During the in situ photocatalytic reduction of GO, oxygen functionalities are gradually removed by virtue of g-C3N4 without any chemicals, resulting in the decreased interlayer spacing, the restrained swelling effect of the hybrid membranes and the weakened electrostatic screening of ion hydration shells, and then the outstanding water desalination is obtained. As-prepared rGO/g-C3N4 hybrid membranes irradiated under UV for 18 h show high rejections towards several ion salts under maintaining the appropriate water flux, especially for sodium salts (67.5% for NaCl, 89.2% for Na2SO4). Based on characterization results, the reason of the difference of the rejections towards various salts and the desalination mechanisms are discussed. This work offers valuable clues for preparing all‑carbon based membranes.

Due to the shorter path length and more channels for lithium ion diffusion and insertion, the two-dimensional (2D) Si nanosheets exhibit superior electrochemical performances in the field of electrochemical energy storage and conversion. Recently, various efforts have been focused on how to synthesize 2D Si nanosheets. However, there are many difficulties to achieve the larger area, high purity of 2D Si nanosheets. Herein, we developed a facile and scalable synthesis strategy to fabricate 2D Si nanosheets, utilizing the unique combination of the water-soluble NaCl particles as the sacrificial template and the hydrolyzed tetraethyl orthosilicate as the silica source, and assisting with the magnesium reduction method. Importantly, the obtained Si nanosheets have a larger area up to 10 μm2. Through combining with reduced graphene oxides (rGO), the Si nanosheets@rGO composite electrode exhibits excellent electrochemical performances. It delivers high reversible capacity about 2500 mAh g−1 at the current density of 0.2 A g−1, as well as an excellent rate capability over 900 mAh g−1 at 2 A g−1 even after 200 cycles.

A novel nickel–cobalt (NiCo)-layered double hydroxide (LDH) saturable absorber (SA) was fabricated by the liquid-phase exfoliation method and applied as the laser modulator for the first time. We successfully investigated the laser modulation performance of the NiCo-LDH SA at 2 µm with a passively Q-switched (PQS) Tm:YAG ceramic laser. The narrowest pulse width of 322.6 ns was obtained, corresponding to a pulse repetition frequency of 119.3 kHz and a single pulse energy of 2.10 µJ. As far as we know, this is the shortest pulse width of PQS Tm:YAG crystal and ceramic lasers with two-dimensional materials saturable absorber. The results show that NiCo-LDH SA is a promising candidate for the application of laser modulators at 2 µm.

The human epidermal growth factor receptor (EGFR) targeting chimeric monoclonal antibody, cetuximab (Erbitux®), is a widely used drug in the treatment of metastatic colorectal cancer. However, the activation of the extensive crosstalk among the EGFR family receptors as well as other tyrosine kinase receptors (RTKs) impairs the efficacy of the drug by fueling acquired resistance. To identify the responsible potential activation pathway underlying cetuximab resistance and generate novel treatment strategies, cetuximab-resistant colorectal cancer cell lines were generated and validated and a functional RNAi screen targeting human RTKs was used to identify extensive receptor tyrosine kinase signaling networks established in resistant cancer cells. MET, Axl, and IGF-1R were identified as contributors to the acquired resistance to cetuximab. Targeting vectored immunoprophylaxis (VIPs) to different RTKs were generated and characterized. Different VIP approaches were evaluated in vivo with parental and cetuximab-resistance xenografts and the RTKs in resistant cancer xenografts were inhibited with VIPs via re-sensitization to cetuximab treatment. Combination of VIPs was more broadly efficacious, mechanistically, due to co-blocking the EGFR/Axl/MET signaling pathway, which was cross-activated in the resistant cell lines. Moreover, a VIP-based procedural treatment strategy not only eliminated the tumor but also afforded long-lasting protection from tumor recurrence and resistance. Overall, EGFR-related RTK pathway-network activation represents a novel mechanism underlying cetuximab resistance. A broad VIP combination strategy and VIP-based procedural treatment strategy may be a recommended addition to cetuximab-based targeted therapy. Our results establish a new principle to achieve combined RTK inhibition and reverse drug resistance using a VIP approach.

The multi-channel reduced graphene oxide membranes with separation function have been synthesized by a simple hydrothermal reduction method and vacuum filtration. In the as-synthesized membranes, the size, number, and type of the nanochannels can be controlled by the reduced temperature. The flux and retention rate of solution are investigated by filtering different size dye molecules. The interception and adsorption effect in the separation process are discussed. Furthermore, the sizes of the nanochannels in the membranes prepared by the different reduced temperatures are estimated. The results indicate that the multi-channel reduced graphene oxide membranes have potential application in water purification area.

Flexible photodetectors based on two-dimensional (2D) transitional metal dichalcogenides (TMDCs) can be used in wearable photoelectronic devices, which have attracted a lot of attention for the last few years. However, most photodetectors based on single layer materials often have low light absorption, and it generally requires complicated and elaborate preparation processes. In this work, we synthesized MoS2 flower-like microspheres with a hydrothermal method, and then a flexible broadband photodetector was prepared by combining MoS2 with a flexible microporous filter membrane. The photodetectors show broad spectral response from 405 nm to 808 nm, with superior responsivity and detectivity reached 0.963 A W−1 and 2.9x1010 Jones respectively under a 405 nm light of 1.77 mW cm−2. Furthermore, these devices also exhibit stable photoelectric responsivity even under various bending conditions. We believe this work will inspire the future development of flexible wearable optoelectronic device.

Lithium-sulfur batteries are considered to be one of the most promising next-generation energy storage systems due to their high theoretical specific capacity and high energy density. However, the inherent disadvantages of poor electrical conductivity, polysulfide shuttle effects, and volume expansion seriously hinder their practical commercial applications. In this study, we have successfully designed a three-dimensional free-standing composite cathode with MoS2 nanosheets growing on the surface of porous graphitized carbon nanofiber. The combination of porous carbon and MoS2 nanosheets can accommodate more sulfur active material, and the graphitized carbon can significantly improve the electrical conductivity of the overall electrode. More importantly, the MoS2 can further adsorb the intermediate polysulfide, preventing the loss of sulfur active material. As a result, the dual-functional composite cathode exhibits an initial reversible capacity of 1385 mA h g−1 at 0.1C. When long-cycled at 1.0C, the capacity can be maintained at 594 mA h g−1 after 500 cycles. When increasing the load of sulfur per unit area, the composite cathode electrodes continue to demonstrate excellent electrochemical performances. The results show that the dual-functional MoS2 Nanosheets/Graphitized Porous Carbon Nanofiber composite is an alternative cathode for future high-performance lithium-sulfur batteries.

High performance, flexible broadband photodetectors based on two-dimensional materials have attracted extensive research interest due to their potential applications. However, these reported flexible photodetectors are generally fabricated into micron-nano devices due to the limited size of two-dimension material, with a narrow spectrum detection range, which has seriously hindered their applications in large-area, broadband photodetector. Herein, we have prepared WS2 nanosheets film via typical hydrothermal intercalation and vacuum filtration methods to fabricate a large-area, flexible broadband photodetector. The fabricated devices respond to a broadband wavelength from visible light to near-infrared light (532–1064 nm), and exhibit a responsivity of 4.04 mA/W and a detectivity of 2.55 × 109 Jones at 532 nm irradiation. Moreover, even in an arbitrary bending condition, our fabricated photodetectors show consistently stable photoresponse characteristics. All the results indicate that our stratagem in this work will be a more convenient and practical guidance for the future flexible optoelectronic devices.

The mechanism of how perceived social support could contribute to left-behind children’s mental well-being remains unclear in mainland China. The purpose of this study was to investigate the direct effect of perceived social support and the mediation role of resilience on left-behind children’s mental well-being. Data of 476 left-behind children in grades 4–9 from 6 schools were collected from a school-based project in Chuzhou District in mainland China. Structural equation modeling indicated that perceived social support elicited a significant direct effect on left-behind children’s mental well-being. Resilience could partially mediate the influence of perceived social support on left-behind children’s mental well-being. These findings could provide cross-cultural evidence for theoretical implications and contribute to evidence-based social policy and social work intervention to promote left-behind children’s mental well-being.

Mn-doped Cu3N films were deposited by cylindrical magnetron sputtering equipment on the common glass at room temperature. The incorporation of Mn can change the preferred growth orientation from Cu-rich plane (111) to N-rich plane (100) due to the improvement of nitridation of Cu. The shrinkage of the lattice and the X-ray photoelectron spectroscopy results reveal that Mn should replace Cu atoms in the lattice or be segregated in the grain boundaries. The thickness of Mn-doped film is smaller than that of the pure one due to the less physisorption of N species among the columnar grains. The mean grain size and the energy gap become larger with increasing Mn concentration to 2.2 at.% and then decrease when the concentration of Mn is higher than 2.2 at.%. Notably, weak doping of 1.5 at.% Mn successfully promotes the decomposed temperature by ∼50 °C. According to the results of XRD and SEM for Mn-doped films annealed in vacuum, a possible decomposed mechanism with increasing the annealing temperature is proposed.

ZnO nanorod arrays were grown on Si substrate by a simple two-step process with sol–gel and hydrothermal methods. To investigate the effect of seed layers on the growth of ZnO nanorods, different numbers of the seed layers have been spin-coated on the substrates. The morphologies of ZnO nanorods including diameter, density, length, and orientation have been studied. The crystallization and band structure have also been discussed. The correlation between the nanorod arrays grown on different seed layers and field emission (FE) properties has also been analyzed. The ZnO nanorod array grown on 4 seed layers possesses the best field emission properties, including a lowest turn-on electric field of 13.3 V/μm and largest field emission current. It can be attributed to the higher field enhancement factor, the vertical orientation, larger density, and better conductivity of the nanorod arrays.

We consider a Cauchy problem for the modified Helmholtz equation. A conditional stability estimate is proved. Two order optimal regularization methods and error estimates are investigated. Numerical experiment shows that these methods work well.

This study tested Social Cognitive Career Theory’s (SCCT) academic performance model using a two-stage approach that combined meta-analytic and structural equation modeling methodologies. Unbiased correlations obtained from a previously published meta-analysis [Robbins, S. B., Lauver, K., Le, H., Davis, D., & Langley, R. (2004). Do psychosocial and study skill factors predict college outcomes? A meta-analysis. Psychological Bulletin, 130 , 261–288.] were used to create the input correlation matrices for subsequent path-analytic tests of the model, using both college GPA and retention as performance criteria. Results suggested that SCCT does an adequate to excellent job of modeling academic performance and persistence, but that model fit was better when general cognitive ability versus high school GPA was used to operationalize the ability/past performance variable. Results are discussed in terms of their fit with SCCT and their practical implications.