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The Sip1Aa protein from Bacillus thuringiensis is highly toxic to Colaphellus bowringi Baly. In order to obtain mutant proteins with higher insecticidal activity, a random recombinant library of Sip1Aa protein was constructed using error-prone PCR. A total number of 100 positive transformants were randomly selected for sequence determination, and 25 mutants (M1 to M25) were selected and expressed the respective Sip1Aa mutants. These Sip1Aa variants had a total of 29 base mutations, with an average of 1.2 base mutations per mutant. Compared with that of the wild-type Sip1Aa protein, the insecticidal activity of the mutants M1 (A31G, Y118C, D227E), M5 (K168R) and M21 (I307T) was significantly decreased, with and LC50 values 4 to 6 times higher than the Sip1Aa protein. The mutant M8 (R174S) showed increase in the insecticidal activity against the Colaphellus bowringi Baly was obtained, with an LC50 value 4-fold less than the Sip1Aa protein. The results of this study provide reference for the molecular modification of Sip1Aa protein and the study of key sites of its insecticidal activity.

Determination and classification of geochemical anomalies is an important step on geochemical exploration. A method called seven levels' classification of geochemical anomalies is presented to determine and classify geochemical anomalies based on backgrounds and cutoff grades of trace elements. The geochemical backgrounds of trace elements resulted from weathering can be described quantitatively by empirical equations in China. Cutoff grades of trace elements are proposed and compiled here. The seven levels' classification method is an objective, distribution free, multivariate, unfixed method and is tested in South Nanling Range, China. Anomaly areas of trace elements are well consistent with their ore-forming geological bodies spatially. Deposits locate generally within their anomaly areas with levels larger than 3 in seven levels' classification. In order to calculate geochemical backgrounds and anomaly levels of trace elements conveniently, GBAL software is developed.

High crystallinity, nano size, and full contact with conductive media are essential for improving the performance of battery materials. Herein, α-MnO2/super-P composite is synthesized via in-situ hydrothermal method. As the cathode material of aqueous Zinc ion battery, the α-MnO2/super-P was maintained 47.0% of discharge capacity after 1000 cycles (decreased from 180 mAh g−1 in the first cycle to 84.6 mAh g−1 in the 1000th cycle) at a high rate of 1.0 A g−1 and reaches the coulombic efficiency to 100% throughout the whole cycles. The excellent electrochemical performance of α-MnO2/super-P is mainly due to the short diffusion path of Zn2+ and the large-scale conductive network of conductive carbon (super P) particles.

Bacillus thuringiensis (Bt) has been used globally as a biopesticide for effective and environmentally friendly pest control. Research has intensified following the development of resistance by lepidopteran species to Bt insecticidal crystal proteins. Discovering new Bt strains with novel toxin properties which can overcome resistance is one of the strategies to improve pesticide sustainability. The genome of the Bacillus thuringiensis LTS290 strain was sequenced and assembled in 252 contigs containing a total of 6,391,328 bp. The novel cry79Aa1 gene from this strain was identified and cloned. Cry79Aa1 contains 729 amino acid residues and a molecular mass of 84.8 kDa by SDS-PAGE analysis. Cry79Aa1 was found to be active against the lepidopteran larvae of Spodoptera exigua, Helicoverpa armigera, and Plutella xylostella with LC50 values of 13.627 µg/mL, 42.8 µg/mL, and 38.086 µg/mL, respectively. However, Cry79Aa1 protein showed almost no insecticidal activity against Leguminivora glycinivorella, although some degree of growth retardation was observed.

3D porous carbon is successfully fabricated from lotus leaves, an abundant and renewable biomass, via a facile and easy-scale up route of carbonization and successive activation by mechanically mixing with KOH. The as-prepared carbon possesses high surface area (3601 m2/g), hierarchical porous structure with interconnected micro/meso/macropores and good level of O–N–S heteroatoms doping. These admirable features endow beneficial multiple synergistic effects for high-performance supercapacitor electrode. The as-obtained carbon exhibit an ultra-high specific capacitance of 523 F/g at 1 A/g in a three-electrode system and 294 F/g at 1.0 A/g in a two-electrode system in 6 mol/L KOH electrolyte with high rate performance of ~85% retention from 1 to 10 A/g and outstanding cycling stability of ~99% capacitance retention after 10000 cycles. These values indicate a high-performance biomass-derived carbon as supercapacitor electrode and may boost the large-scale application of 3D porous carbons doped by heteroatoms for energy storage.

A luminescent three-dimensional metal-organic framework generally formulated as [Zn2(OH)(sip)(bpe)(H2O)]H2O (1), has been hydrothermally synthesized and characterized. It represents a new two-fold interpenetrated pillared-layer framework with (63)(69 · 8) topology constructed from π-electron-rich rigid ligand 5-sulfoisophthalic acid coupled with auxiliary ligand 1,2-bis(4-pyridyl)ethane. Interestingly, the strong emission of 1 could be quenched efficiently by trace amounts of Fe3 + at room temperature, even in the presence of other competing analogues, which indicated that 1 can serve as an excellent sensor for specific selective identification and quantification of Fe3 +.

Combination therapy provides an efficient way to overcome the potential multidrug resistance and enhance anticancer efficacy. In this work, a biodegradable pH-responsive hollow mesoporous silica nanoparticle (HMSN-GM-CS-FA) was developed for co-delivery of pheophorbide a (PA) and doxorubicin (DOX). This drug delivery system possessed controlled particle size and larger inner hollow core, which endowed the nanoparticle with excellent encapsulation capacities. The uptake efficiency of drug loaded nanoparticles HMSNs-GM-CS-FA@DOX/PA in cancer cells was greatly improved by folic acid-mediated endocytosis. The nanocarrier showed excellent drug controlled release properties based on the pH-dependent swelling effect of the coating layer. More importantly, the nanoplatform could fully combine photothermal-, photodynamic- and chemotherapies to develop synergistic antitumor efficacy. This strategy of integrating multi-therapeutic functions in one single formulation promised a powerful route to construct intelligent co-delivery carriers for efficient combinational clinical application.

We reported a new and facile synthesis route to prepare polyaniline (PANI) nanowire@Co-Fe LDHs nanosheets in two steps. The PANI@Co-Fe LDHs has excellent OER activity with a small overpotential of 261 mV at the current density of 10 mA·cm−2and a small Tafel slope of 67.85 mV·dec−1. The PANI@Co-Fe LDHs also has long-term performance and stability. The excellent electrocatalytic performance of the catalyst depends on the good electrical conductivity of PANI and the effect of the two-dimensional (2D) layered structure of Co-Fe LDHs. The work opens a new application for energy storage and conversion.

There has been considerable effort made in recent years for research groups and other organizations to build up large collections of strains of Bacillus thuringiensis in the search for genes encoding novel insecticidal toxins, or encoding novel metabolic pathways. Whilst next generation sequencing allows the detailed genetic characterization of a bacterial strain with relative ease it is still not practicable for large strain collections. In this work we assess the practicability of mining a mixture of genomic DNA from a two thousand strain collection for particular genes. Using PCR the collection was screened for both a rare (cry15) toxin gene as well as a more commonly found gene (vip3A). The method was successful in identifying both a cry15 gene and multiple examples of the vip3A gene family including a novel member of this family (vip3Aj). A number of variants of vip3Ag were cloned and expressed, and differences in toxicity observed despite extremely high sequence similarity.

A novel porous metal–organic framework [Pb2(TETA)]·6H2O (1) has been prepared by hydrothermal reaction of lead(II) with a flexible bifunctional macrocyclic ligand. The 1D Pb O chains are cross-linked via the flexible macrocyclic rings of TETA4 − ligands in two different directions to form 3D framework with highly solvent accessible volume.

One-dimensional (1D) cobalt acetate hydroxide (Co 5 (OH) 2 (CH 3 COO) 8 ·2H 2 O) prisms has been obtained through a low temperature re-crystallization process in the dissolvant of ethanol and then transferred to cobalt oxide by calcining in the air. Cobalt oxide keeps the outside configuration of the 1D cobalt acetate hydroxide but turns to be boxes with hollow structure inside through the Kirkendall effect. The precursor prisms and polycrystalline boxes both have length of about 3 μm, width of 300 nm and height of 300 nm characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The electrochemical measurement results show that the hollow Co 3 O 4 structures exhibit wonderful capacitive properties with high capacitance and good cyclicity.

In this study, solid ZnSn(OH) 6 microspheres were successfully synthesized with water-soluble biopolymer sodium alginate as crystal growth modifiers and ammonia as basic source under hydrothermal conditions. In the alkaline solution, the solid ZnSn(OH) 6 spheres can be gradually corroded by ammonia to form hollow ZnSn(OH) 6 spheres under the hydrothermal conditions through a dissolution–reprecipitation mechanism. Gas sensor tests indicate that hollow ZnSn(OH) 6 spheres have a better response to ethanol compared to solid ZnSn(OH) 6 spheres, which might be due to the hollow structure-resulted larger specific surface area. This method would provide a potential route for the synthesis of hollow ternary compounds.