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Acting as a double-edged sword, the blood–brain barrier (BBB) is essential for maintaining brain homeostasis by restricting the entry of small molecules and most macromolecules from blood. However, it also largely limits the brain delivery of most drugs. Even if a drug can penetrate the BBB, its accumulation in the intracerebral pathological regions is relatively low. Thus, an optimal drug-delivery system (DDS) for the management of brain diseases needs to display BBB permeability, lesion-targeting capability, and acceptable safety. Biomimetic DDSs, developed by directly utilizing or mimicking the biological structures and processes, provide promising approaches for overcoming the barriers to brain drug delivery. The present review summarizes the biological properties and biomedical applications of the biomimetic DDSs including the cell membrane-based DDS, lipoprotein-based DDS, exosome-based DDS, virus-based DDS, protein template-based DDS and peptide template-based DDS for the management of brain diseases.

A glassy carbon electrode (GCE) modified with gold nanoparticles loading on the reduced graphene oxide (rGO)-multi-walled carbon nanotubes (MWCNTs) composite film was fabricated by a two-step procedure. Firstly, rGO-MWCNTs composite were prepared by in-situ chemical reduction with hydrazine as a reducing agent. Then, gold nanoparticles (AuNPs) were deposited on the surface of rGO-MWCNTs using simple cyclic voltammetry. This modified electrode was characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and electrochemical methods. Furthermore, the electrochemical behavior of bisphenol A (BPA) was also investigated using this modified electrode. The results showed that the modified electrode had high electrochemical activity for the oxidation of BPA. In 0.10 M phosphate buffer (PBS, pH 7.0), the linear range for the determination of BPA with differential pulse voltammetry (DPV) was in the range of 5.0 × 10−9−1.0 × 10−7M and 1.0 × 10−7−2.0 × 10−5M. The detection limit was 1.0 × 10−9M (S/N= 3). The as-prepared modified electrode was successfully used to determine BPA in river water and the shopping receipt samples with recoveries range of 97%–110% and 98%–104%, respectively.

Rational design of the physicochemical properties of nanocarriers can optimize their pharmacokinetics, biodistribution, intratumoral penetration and tumor bioavailability. In particular, particle shape is one of the crucial parameters that can impact the circulation time, tumor accumulation and tumor cell internalization of nanocarrier. Biomimetic reconstituted high-density lipoprotein (rHDL), by mimicking the endogenous shape and structure of high-density lipoprotein, has been indicated as a promising tumor-targeting nanoparticulate drug delivery system whereas the effect of shape on tumor-targeting efficiency has not been fully evaluated. Herein, we constructed apolipoprotein E-based biomimetic rHDL in both discoidal form (d-rHDL) and spherical form (s-rHDL), and compared their efficiency in glioblastoma multiforme (GBM)-targeting delivery. s-rHDL showed higher cellular association in GBM cells especially at a high exposure dosage or after a long incubation time. Moreover, it exhibited deeper penetration in 3D GBM spheroidsin vitroand higher accumulation at the GBM sitein vivowith the GBM-targeting accumulation of s-rHDL increased by 73% when compared with that of d-rHDL at 24 h post-injection. The findings collectively indicated that s-rHDL might serve as a more efficient nanocarrier for glioblastoma-targeting drug delivery.

A simple model of urban passenger transport was developed using computer based software called Long-range Energy Alternatives Planning System (LEAP), the model was used to carry out a research associated with urban passenger transport in Beijing to analyze the situation of energy consumption and environmental emissions ofCO2, CO, CH4, N2O, NOx, and SO2 for the base year 2012 and extrapolated till 2030 for the future predictions. The paper established four scenarios of business as usual, public transport, new energy vehicle, and P&N, and assessed the energy consumption and environmental emissions reduction potential of each scenarios in order to propose an optimal transport policy which have an excellent effect on reducing energy consumption and environmental emissions.

The paper considered a number of available pathways to move to low-carbon transport with low energy consumption and greenhouse gas (GHG) emissions, including: promoting alternative energy carriers for all transport modes and improving vehicle fuel efficiency; avoiding or reducing the need to travel by private car through pricing and integrated land-use and transport planning policies; encouraging a modal shift to more energy-efficient mode for a particular trip through pricing mechanisms, regulation, and investments. It’s also mentioned that a combination of the available policies and the collaboration between all relevant institutions and policymakers are necessary to meet energy saving and GHG reduction goals.

With the development of internet, we usually hope to recommender the possible interested products to the consumers through analyzing to the consumers history records, and obtain better sale records in fruits marketing system. collaborative filtering algorithm is widely used in Fruits Recommendation System, and item-based KNN collaborative filtering algorithm completes clustering and recommendation through analyzing the similarity of the items. Traditional item-based KNN collaborative filtering algorithm could not deal with huge scale fruits sale data effectively to complete recommendation work. In this paper, for the large scale data, we propose a distributed item-based KNN collaborative filtering algorithm based on MapReduce cloud computing platform. The experimental results show that the algorithm has a high speed-up, and a good expansibility.

Through analysis and research about Baptista and Alvarez chaotic encryption algorithm, the author points out that the Baptisata algorithm is not high efficiency in practical application, the cryptograph distribution is easy to be attacked by known plaintext; Alvarez algorithm can be deducted key information through the tent map and there is hidden information leakage. The more complex chaotic mapping can be used to instead of tent map, but scheme are not safe even after the changing , there are still many problems, this reflects that the use of chaotic mapping to achieve information security still has a long way to go.

The human vitamin D receptor (hVDR) is a member of the nuclear receptor superfamily of transcriptional regulators. Here we show that tryptophan 286 of the hVDR is critical for ligand binding and transactivation of 1,25‐dihydroxyvitamin D3[1,25(OH)2D3] target genes. Two mutants of the hVDR were produced, W286A and W286F, in which the tryptophan was replaced with an alanine or a phenylalanine, respectively. The W286A mutant did not bind 1,25(OH)2D3, interact with steroid receptor coactivator 1 (SRC‐1) in vitro, or activate transcription. Moreover, the W286A receptor did not heterodimerize in a ligand‐dependent manner with the human retinoid X receptor α (hRXRα). Although the W286F receptor heterodimerized with hRXRα, interacted with SRC‐1, and bound 1,25(OH)2D3, its capacity to transactivate was attenuated severely. Thus, tryptophan 286 of hVDR plays an important role in specific 1,25(OH)2D3ligand interaction and subsequently in hVDR/RXR interaction, SRC‐1 binding, and ligand‐dependent transactivation of 1,25(OH)2D3target genes. These results identify the first amino acid that is absolutely required for ligand binding in the VDR and further define the structure‐function relationship of 1,25(OH)2D3interaction with its receptor.

The human vitamin D receptor (hVDR) is a member of the nuclear receptor superfamily of transcriptional regulators. Here we show that tryptophan 286 of the hVDR is critical for ligand binding and transactivation of 1,25‐dihydroxyvitamin D3[1,25(OH)2D3] target genes. Two mutants of the hVDR were produced, W286A and W286F, in which the tryptophan was replaced with an alanine or a phenylalanine, respectively. The W286A mutant did not bind 1,25(OH)2D3, interact with steroid receptor coactivator 1 (SRC‐1) in vitro, or activate transcription. Moreover, the W286A receptor did not heterodimerize in a ligand‐dependent manner with the human retinoid X receptor α (hRXRα). Although the W286F receptor heterodimerized with hRXRα, interacted with SRC‐1, and bound 1,25(OH)2D3, its capacity to transactivate was attenuated severely. Thus, tryptophan 286 of hVDR plays an important role in specific 1,25(OH)2D3ligand interaction and subsequently in hVDR/RXR interaction, SRC‐1 binding, and ligand‐dependent transactivation of 1,25(OH)2D3target genes. These results identify the first amino acid that is absolutely required for ligand binding in the VDR and further define the structure‐function relationship of 1,25(OH)2D3interaction with its receptor.