Using special Janus nanobelt as constitutional unit to construct anisotropic conductive array membrane for concurrently affording color-tunable luminescence and superparamagnetism

We have used electrospinning technology to fabricate a tri-functional nanobelt array membrane exhibiting tunable anisotropic electrical conduction, superparamagnetism and color-tunable luminescence by using a lab-made co-axis//single-axis spinneret and an aluminum drum collection device. Each one-dimensional (1D) Janus nanobelt is composed of luminescent-superparamagnetic bifunctional [Fe₃O₄/polymethyl methacrylate (PMMA)]@[Tb(BA)₃phen/Eu(BA)₃phen/PMMA] coaxial nanobelt and conducting polyaniline (PANI)/PMMA nanobelt. Moreover, all Janus nanobelts are aligned in the same manner to generate a two-dimensional (2D) array film. The conductance along the length is much stronger than the conductance in the width (two perpendicular directions). Therefore, the array membrane has excellent anisotropic electrical conduction. The conduction ratio reaches 10⁸ times between the length and width of the Janus nanobelt array membrane, which is the highest conduction ratio between the two perpendicular directions for nanobelt materials reported internationally. Furthermore, we can modulate the degree of electrically conducting anisotropy of the samples by varying the amount of PANI. In addition, the Janus nanobelt array membrane is concurrently endowed by superior and adjustable superparamagnetism and photoluminescence. Importantly, the innovative philosophy and manufacturing technique of the new Janus nanobelt array membrane provide an easy way to prepare multifunctional nano-membranes.

Flexible peculiar-structured Janus nanobelts and their array membranes of high electrically conductive anisotropy, luminescence and superparamagnetism were fabricated via electrospinning.     

Novel oligopeptide nanoprobe for targeted cancer cell imaging

Here we designed and constructed a tryptophan-phenylalanine-phenylalanine-tryptophan (WFFW) tetrapeptide, which generated photostable and tunable fluorescence emission signals from 340 nm to 500 nm. The WFFW tetrapeptide could self-assemble into a spherical nanostructure with enhanced fluorescence intensity. Driven by π–π stacking and hydrogen bond interaction, WFFW co-assembled with arginine-glycine-aspartic acid (RGD) modified WFFW to form a cancer-targeted fluorescent nanoprobe, which could selectively image the cancer cells.

Co-assembly of WFFW tetrapeptide and RGDWFFW heptapeptide generated the photostable and fluorescence-tunable nanoprobe, which could selectively image the cancer cells.     

Cadmium tolerance and accumulation characteristics of wetland emergent plants under hydroponic conditions

For the purpose of screening a potential Cd-hyperaccumulator for Cd-contaminated soil in paddy fields, four kinds of wetland emergent plants (Iris sibirica L., Acorus calamus L., Typha orientalis Presl and Cyperus alternifolius L.) were investigated for their cadmium tolerance and accumulation characteristics under hydroponic conditions. The physiological responses of plants, Cd concentration in tissues, Cd accumulation, bioaccumulation factor (BCF) and translocation factor (TCF) were investigated to evaluate the abilities of wetland emergent plants to absorb and accumulate Cd. In comparison with the other selected emergent plants, Iris sibirica L. has the strongest Cd-tolerance for the absence of Cd toxic symptoms and a Cd concentration as high as 127.3 mg kg⁻¹ in shoots. Due to its large biomass, the Cd accumulation could reach up to 9.4 mg per plant in roots and 5.7 mg per plant in shoots, respectively. Iris sibirica L. possesses the highest TCF, and its BCF for Cd increased with increasing concentration of spiked Cd in the hydroponic solutions. The results indicate that Iris sibirica L. is a potential Cd-hyperaccumulator that may have a strong capacity for extracting Cd from Cd-contaminated paddy soils.

Four kinds of wetland emergent plants (Iris sibirica L., Acorus calamus L., Typha orientalis Presl and Cyperus alternifolius L.) were investigated for their cadmium tolerance and accumulation characteristics under hydroponic conditions.     

Responses of the electron transfer capacity of soil humic substances to agricultural land-use types

Humic substances (HS) are redox-active organic compounds that constitute a major fraction of natural organic matter in soils. The electron transfer capacity (ETC) of soil HS is mainly dependent on the type and abundance of redox-active functional groups in their structure. It is unclear whether or not agricultural land-use types can affect the ETC of HS in soils. In the present study, we evaluate the responses of ETCs of soil humic acids (HA) and fulvic acids (FA) to different agricultural land-use types. Our results show that both HA and FA of paddy soil showed the highest ETCs, followed by tomato soil, celery cabbage soil, grapevine soil, and myrica rubra soil, respectively. Agricultural land-use types could affect the transformation and decomposition of HS in soils, and thus further change the intrinsic chemical structures associated with ETC. Consequently, the ETC of soil HS exerts a significant difference among different agricultural land-use types. The results of this study could give insight into the roles of HS redox properties on the transport, fate, and redox conversion of organic and inorganic pollutants in different agricultural soils.

Agricultural land-use types could affect the transformation and decomposition of HS in soils, and thus further change the intrinsic chemical structures associated with ETC.     

Synthesis and characterization of TiO2/graphene oxide nanocomposites for photoreduction of heavy metal ions in reverse osmosis concentrate

In this study, graphene oxide (GO), titanium dioxide (TiO₂) and TiO₂/GO nanocomposites were synthesized as the catalysts for photoreduction of endocrine disrupting heavy metal ions in reverse osmosis concentrates (ROC). The morphology, structure and chemical composition of these catalysts were characterized by scanning electron microscopy, transmission electron microscopy, powder X-ray diffraction, Brunauer–Emmett–Teller analysis, Barrett–Joyner–Halenda, Fourier transform infrared spectroscopy and Raman spectroscopy. The photocatalytic experiments showed that TiO₂/GO nanocomposites exhibit a higher photoreduction performance than pure TiO₂ and GO. Under the optimal conditions, the removal rates of Cd²⁺ and Pb²⁺ can reach 66.32 and 88.96%, respectively, confirming the effectiveness of photoreduction to reduce the endocrine disrupting heavy metal ions in ROC resulted from the combined adsorption–reduction with TiO₂/GO nanocomposites.

TiO₂/GO nanocomposites were synthesized successfully and exhibited an excellent ability to reduce heavy metal ions in reverse osmosis concentrate.     

Severity evaluation of obstructive sleep apnea based on speech features

Sleep and Breathing - There are upper airway abnormalities in patients with obstructive sleep apnea (OSA), and their speech signal characteristics are different from those of unaffected people. In...     

Structure-Based Design of GNE-495, a Potent and Selective MAP4K4 Inhibitor with Efficacy in Retinal Angiogenesis

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