In this study, we introduced a targeting polymer poly(ethylene glycol)–folic acid (PEG–FA) on the surface of polydopamine (PDA)-modified mesoporous silica nanoparticles (MSNs) to develop the novel ...nanoparticles (NPs) MSNs@PDA–PEG–FA, which were employed as a drug delivery system loaded with doxorubicin (DOX) as a model drug for cervical cancer therapy. The chemical structure and properties of these NPs were characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, N2 adsorption/desorption, dynamic light scattering-autosizer, thermogravimetric analysis, and Fourier transform infrared spectroscopy. The pH-sensitive PDA coating served as a gatekeeper. The in vitro drug release experiments showed pH-dependent and sustained drug release profiles that could enhance the therapeutic anticancer effect and minimize potential damage to normal cells due to the acidic microenvironment of the tumor. These MSNs@PDA–PEG–FA achieved significantly high targeting efficiency, which was demonstrated by the in vitro cellular uptake and cellular targeting assay. Compared with that of free DOX and DOX-loaded NPs without the folic targeting ligand, the FA-targeted NPs exhibited higher antitumor efficacy in vivo, implying that they are a highly promising potential carrier for cancer treatments.
Full text
Available for:
IJS, KILJ, NUK, PNG, UL, UM
We fabricated tantalum pentoxide (Ta
O
) channel waveguides and used them to experimentally demonstrate higher-order mode supercontinuum (SC) generation. The Ta
O
waveguide has a high nonlinear ...refractive index which was in an order magnitude of 10
cm
/W and was designed to be anomalously dispersive at the pumping wavelength. To the best of our knowledge, this is the first time a higher-order mode femtosecond pump based broadband SC has been measured from a nonlinear waveguide using the phase-matching method. This enabled us to demonstrate a SC spectrum spanning from 842 to 1462 nm (at - 30 dB), which corresponds to 0.83 octaves, when using the TM
waveguide mode. When using the TE
mode, the SC bandwidth is slightly reduced for the same excitation peak power. In addition, we theoretically estimated and discussed the possibility of using the broadband higher-order modes emitted from the Ta
O
waveguide for trapping nanoparticles. Hence, we believe that demonstrated Ta
O
waveguide are a promising broadband light source for optical applications such as frequency metrology, Raman spectroscopy, molecular spectroscopy and optical coherence tomography.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Public health is threatened by deteriorated water quality due to bacterial regrowth and uncontrolled growth-related problems in drinking water distribution systems (DWDSs). To investigate the scope ...of this problem, a two-year field study was conducted in south China. The amount of assimilable organic carbon (AOC), total cell concentrations (TCC), and intact cell concentrations (ICC) of water samples were determined by flow cytometry. The results indicated that ICC was significantly correlated to AOC concentration when the chlorine concentration was less than 0.15 mg/L, and ICC was lower at chlorine concentrations greater than 0.15 mg/L, suggesting that free chlorine level had effect on AOC and ICC. To further analyze the effect of disinfectant on AOC and bacterial growth, we designed an orthogonal experiment with different dosages of two commonly used disinfectants, chlorine and chloramine. The results demonstrated that high concentrations of free chlorine (＞0.15 mg/L) and chloramine (＞0.4 mg/L) were associated with relatively low proportions of intact cells and cultivable bacteria. Compared with chlorine, chloramine tended to cause lower AOC level and intact cells, likely because the chlorinated disinfection byproducts (DBPs) were more easily absorbed by bacteria than the chloraminated DBPs. Based on the statistical analysis of 240 water samples, ICC was limited when AOC concentration was less than 135 μg/L, while temperature and the number of small-size particles showed positive effects on ICC (P＜0.05). We conclude that the use of chloramine and controlling particle numbers should be suitable strategies to limit bacterial regrowth.
Display omitted
•Only with chlorine less than 0.15 mg/L, ICC was significantly correlated to AOC.•Cl2 above 0.15 mg/L or NH2Cl above 0.4 mg/L was associated with low ICC proportion.•Chloramine tended to cause lower AOC level and intact cells proportions.•ICC was found to be limited when AOC was less than 135 μg/L.•Particles control and use of chloramine were proper ways to limit bacterial growth.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
•A novel CO-enhanced multi-mode synergistic antibacterial nanoplatform was developed.•Controllable CO generation co-driven by the PTT and PDT effects of ICG.•CO notably enhances the antibacterial and ...biofilm ablation activities of PTT and PDT.•CO effectively reduces the inflammation caused by bacterial infections, PTT and PDT.•Highly effective treatment of urinary catheter infection and subcutaneous abscesses.
Photothermal therapy (PTT) and photodynamic therapy (PDT) have garnered much attention for effectively treating biofilm infections. However, even highly efficient PTT reagents and photosensitizers still require high concentration and irradiation doses to ablate biofilms due to their limited permeability in biofilms, while these attempts tend to cause severe tissue damage and inflammation. Herein, a CO-enhanced multi-mode synergistic antibacterial nanoplatform (ICG&CO@G3KBPY) with controllable CO generation behavior, notably enhanced biofilm penetration, antibacterial, biofilm ablation, and anti-inflammatory activity was effectively developed to combat biofilm infections. ICG&CO@G3KBPY is constructed by physically encapsulating indocyanine green (ICG) and manganese pentacarbonyl bromide (MnBr(CO)5) into a 2,2′-bipyridine-4-carboxylic (BPY)-modified peptide dendrimer-based nanogel (G3KBPY). ICG&CO@G3KBPY can rapidly generate massive quantities of CO under the co-driven effects of PTT and PDT. Notably, the generated CO not only promotes the biofilm penetration of ICG and enhances the antibacterial and biofilm eradication performance of PTT and PDT, but also significantly alleviates the inflammatory response caused by bacterial infection, PTT and PDT. The combination of CO, PTT, and PDT offers excellent biofilm ablation effects in treating urinary catheter infection and subcutaneous abscesses, accompanied by good biocompatibility. This study provides an efficient and safe multi-mode synergistic antibacterial strategy for combatting biofilm infections.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•MoS2-RGO sponges are prepared via freeze drying and thermal treatment process.•MoS2-RGO sponges are used as free-standing electrodes for sodium-ion batteries.•MoS2-RGO sponges exhibit a porous ...conductive sandwich structure.•A specific capacity of 372.0mAhg−1 at 100mAg−1 is maintained after 50 cycles.
Currently, the search for high capacity, low cost and free-standing electrodes for sodium-ion batteries (SIBs) is one of the major challenges in energy storage field. In this work, we rationally design MoS2-reduced graphene oxide (MS-RGO) sponges via a simple freeze-drying of ammonium tetrathiomolybdate-graphene oxide mixed solution and a subsequent thermal treatment in N2/H2 atmosphere, and employ these sponges as free-standing anodes for SIBs. The MS-RGO sponges exhibit a porous conducive structure that can facilitate the charge transport and thus show an excellent electrochemical performance. The free-standing sponge electrodes display a maximal reversible specific capacity of 372.0mAhg−1 (0.49mAhcm−2) at a current density of 100mAg−1 after 50 cycles. Even at a high current density of 1Ag−1, a capacity of 192.2mAhg−1 (0.25mAhcm−2) is maintained after 345 cycles. The results show that MS-RGO sponges are promising free-standing electrode materials for rechargeable SIBs.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
To bridge the gap between laboratory research and commercial applications, it is vital to develop scalable methods to produce large quantities of high-quality and solution-processable few-layer ...phosphorene (FLBP). Here, we report an ultrafast cathodic expansion (in minutes) of bulk black phosphorus in the nonaqueous electrolyte of tetraalkylammonium salts that allows for the high-yield (>80%) synthesis of nonoxidative few-layer BP flakes with high crystallinity in ambient conditions. Our detailed mechanistic studies reveal that cathodic intercalation and subsequent decomposition of solvated cations result in the ultrafast expansion of BP toward the high-yield production of FLBP. The FLBPs thus obtained show negligible structural deterioration, excellent electronic properties, great solution processability, and high air stability, which allows us to prepare stable BP inks (2 mg/mL) in low-boiling point solvents for large-area inkjet printing and fabrication of optoelectronic devices.
Full text
Available for:
IJS, KILJ, NUK, PNG, UL, UM
The soil microbial community plays an important role in terrestrial carbon and nitrogen cycling. However, microbial responses to climate warming or cooling remain poorly understood, limiting our ...ability to predict the consequences of future climate changes. To address this issue, it is critical to identify microbes sensitive to climate change and key driving factors shifting microbial communities. In this study, alpine soil transplant experiments were conducted downward or upward along an elevation gradient between 3,200 and 3,800 m in the Qinghai-Tibet plateau to simulate climate warming or cooling. After a 2-year soil transplant experiment, soil bacterial communities were analyzed by pyrosequencing of 16S rRNA gene amplicons. The results showed that the transplanted soil bacterial communities became more similar to those in their destination sites and more different from those in their "home" sites. Warming led to increases in the relative abundances in Alphaproteobacteria, Gammaproteobacteria, and Actinobacteria and decreases in Acidobacteria, Betaproteobacteria, and Deltaproteobacteria, while cooling had opposite effects on bacterial communities (symmetric response). Soil temperature and plant biomass contributed significantly to shaping the bacterial community structure. Overall, climate warming or cooling shifted the soil bacterial community structure mainly through species sorting, and such a shift might correlate to important biogeochemical processes such as greenhouse gas emissions. This study provides new insights into our understanding of soil bacterial community responses to climate warming and cooling.
•A theoretical model of surface generation and subsurface damage was established.•The model considered the shape, size, and spatial distribution of the particles and the brittle-ductile removal ...effect.•The models were successfully validated by a series of lapping experiments.•The material removal mechanism and lapping tool wear characteristics were investigated.•The influence mechanism of tool load on surface and subsurface state was revealed.
Fixed abrasive lapping (FAL) is a promising technology increasingly used for finishing optical mirrors and molds in a number of materials due to its high finishing efficiency, environmental friendliness, and relatively better surface and subsurface quality. A theoretical model for fixed-abrasive lapping of optical glass was developed in this paper by using indentation fracture mechanics, contact mechanics, mathematical statistics, lapping kinematics, and convolution iterative principle to provide an enhanced scientific understanding of the surface microtopography generation and subsurface damage (SSD) control mechanisms. In the modeling, the influence of the shape, size, and spatial distribution of abrasive particles and the ductile and brittle removal mechanisms of the material were considered. A series of lapping experiments on fused silica glass was carried out to quantitatively analyze the feasibility and accuracy of the model and study the influence mechanism of process parameters on the surface and subsurface state. Results indicated that the models could well predict the surface micromorphology and the SSD depth, and the range of sharpness angle of abrasive particles and tool load affected the predicted SSD range. In addition, the material removal mechanism and lapping tool wear characteristics were revealed by the surface structure and element component analysis. Finally, the FAL process was optimized by the evaluation indices of material removal rate (MRR), surface roughness, and SSD.
Display omitted
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•A novel series of UV PLM Mg2Ln2Ge3O11:Bi3+ (Ln = Gd/La/Y/Lu) are synthesized.•Their UV PersL spectra can be tuned from 350 to 310 nm via element substitution.•Mg2Lu2Ge3O11:Bi3+ (MLG) showed UVB ...PersL without visible emission.•The optical properties of MLG made it appear similar to a fluorescent powder.•A triple-mode information encryption pattern is designed based on MLG.
Persistent luminescent material (PLM) is promising candidate in anti-counterfeiting field. Specifically, Ultraviolet (UV) PLM without visible persistent luminescence (PersL) can realize information encryption with high concealment and security. However, UV-PLM has not yet been applied in anti-counterfeiting owing to the lack of invisible UV-PLM. Herein, we, for the first time, report a novel invisible ultraviolet-B (UVB) PLM and applied in advanced anti-counterfeiting and encryption field, exhibting its unique advantages. First, we prepared a novel series of UV-PLM, Mg2Ln2Ge3O11:Bi3+ (Ln = Gd, La, Y, and Lu) and then realized the tuning of PersL from 350 to 310 nm via element substitution. Specifically, Mg2Lu2Ge3O11:Bi3+ (MLG) can emit dim visible photoluminescence under 254 nm excitation and produce UVB-PersL without visible region after the excitation was ceased, which caused it appear like an ordinary fluorescent powder. Interestingly, the invisible UVB-PersL can be detected using a camera realizing the information encryption with high concealment. Moreover, owing to its unique optical properties, mixing MLG with different colors of fluorescent powder endows it with the ability to camouflage. Based on MLG, we designed a triple-mode information encryption method and demonstrated its unique advantages in the field of advanced anti-counterfeiting.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Seldom could metals and alloys maintain excellent properties in cryogenic condition, such as the ductility, owing to the restrained dislocation motion. However, a face-centered-cubic (FCC) CoCrFeNi ...high-entropy alloy (HEA) with great ductility is investigated under the cryogenic environment. The tensile strength of this alloy can reach a maximum at 1,251±10 MPa, and the strain to failure can stay at as large as 62% at the liquid helium temperature. We ascribe the high strength and ductility to the low stacking fault energy at extremely low temperatures, which facilitates the activation of deformation twinning. Moreover, the FCC→HCP (hexagonal close-packed) transition and serration lead to the sudden decline of ductility below 77 K. The dynamical modeling and analysis of serrations at 4.2 and 20 K verify the unstable state due to the FCC→HCP transition. The deformation twinning together with phase transformation at liquid helium temperature produces an adequate strain-hardening rate that sustains the stable plastic flow at high stresses, resulting in the serration feature.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
PDF
