Effect of some Ghanaian plant components on control of two stored-product insect pests of cereals

In an attempt to find natural and cheaper methods for the control of stored-product pests of cereals, some traditionally useful Ghanaian plant materials were evaluated. Hexane+isopropyl alcohol extract of leaves of Ocimum viride proved most effective in the control of Tribolium castaneum (Coleoptera: Tenebrionidae) and Sitophilus oryzae (Coleoptera: Curculionidae), followed by that of Chromolaena odorata. O. viride showed strong repellent activity and thus deterred the insects from feeding. It reduced survival of both insect pests to less than 25% after 10 days of treatment at concentrations of 0.1 mg ml(-1) and above. The results show the potential of O. viride and C. odorata in the control of stored-product insects.     

Sonocrystallization of Interesterified Fats with 20 and 30% C16:0 at <Emphasis Type="Italic">sn</Emphasis>-2 Position

The objective of this study was to induce crystallization in enzymatically interesterified fats (IE) with 20 and 30% palmitic acid at the sn-2 position using high intensity ultrasound (HIU). The physical blends (PB) used to prepare these two IE were consisted of tripalmitin and high oleic sunflower oil and contained 13.2 and 27.1% tripalmitin, respectively. Crystallization behavior of IE was compared with PB at supercoolings of 9, 6 and 3 °C. Results show that the melting point, SFC, and crystallization rate of PB were higher than IE and were driven mainly by tripalmitin content. HIU induced crystallization and generated small crystals in the IE samples. At 9 °C supercooling, sonication did not increase the viscosity of IE C16:0 20%, while that of the IE C16:0 30% increased significantly from 192.4 ± 118.9 to 3297.7 ± 1368.6 Pa·s. The elastic modulus (G’) for IE C16:0 30% increased from 12521 ± 2739.8 to 75076.7 ± 18259 Pa upon sonication at 9 °C supercooling, while the G’ of the IE C16:0 20% did not increase. Similar behavior was observed for the other supercoolings tested. This research suggests that HIU can improve the functional properties of IE with low content of C16:0 creating more viscous and elastic materials. These fats with low C16:0 content and improved functional properties could be used as trans-free fat alternatives.     

An autonomous self‐healing hydrogel based on surfactant‐free hydrophobic association

Self‐healing hydrogels are attractive for a variety of applications including wound dressings and coatings. This paper describes the facile preparation and characterization of an autonomous self‐healing hydrogel system comprising surfactant‐free hydrophobic associations. The hydrogel comprised a copolymer of benzyl methacrylate (B), octadecyl methacrylate (O), and methacrylic acid (MA). The hydrogels were prepared via a controlled dehydration procedure to achieve the formation of strong intermolecular hydrophobic associations of the octadecyl groups above a critical polymer concentration. Fractured hydrogels healed within 30 min without any external intervention. Increasing hydrogel polymer content from 31 wt % to 39 wt % resulted in a threefold increase in the shear modulus and 50% reduction of the relaxation time. Addition of 4 mM NaCl to a hydrogel of 31 wt % polymer content resulted in 2.5 times longer relaxation time and 24% decrease in shear modulus. The hydrogels swelled up water by up to four times its weight, which corroborates the robustness of the hydrophobic association crosslinks. The bulk properties of the hydrogels are discussed in terms of the hydrophobic associations of the O‐groups and the electrostatic interaction of the MA‐groups in the polymer chains. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44800.     

Multifunctional Mo–N/C@MoS2 Electrocatalysts for HER,OER, ORR,and Zn–Air Batteries

Replacement of noble‐metal platinum catalysts with cheaper, operationally stable, and highly efficient electrocatalysts holds huge potential for large‐scale implementation of clean energy devices. Metal–organic frameworks (MOFs) and metal dichalcogenides (MDs) offer rich platforms for design of highly active electrocatalysts owing to their flexibility, ultrahigh surface area, hierarchical pore structures, and high catalytic activity. Herein, an advanced electrocatalyst based on a vertically aligned MoS₂ nanosheet encapsulated Mo–N/C framework with interfacial Mo–N coupling centers is reported. The hybrid structure exhibits robust multifunctional electrocatalytic activity and stability toward the hydrogen evolution reaction, oxygen evolution reaction, and oxygen reduction reaction. Interestingly, it further displays high‐performance of Zn–air batteries as a cathode electrocatalyst with a high power density of ≈196.4 mW cm^?2 and a voltaic efficiency of ≈63 % at 5 mA cm^?2, as well as excellent cycling stability even after 48 h at 25 mA cm^?2. Such outstanding electrocatalytic properties stem from the synergistic effect of the distinct chemical composition, the unique three‐phase active sites, and the hierarchical pore framework for fast mass transport. This work is expected to inspire the design of advanced and performance‐oriented MOF/MD hybrid‐based electrocatalysts for wider application in electrochemical energy devices.     

Evolutionary multi criteria design optimization of robot grippers

This paper explores the use of intelligent techniques to obtain optimum geometrical dimensions of a robot gripper. The optimization problem considered is a non-linear, complex, multi-constraint and multicriterion one. Three robot gripper configurations are optimized. The aim is to find Pareto optimal front for a problem that has five objective functions, nine constraints and seven variables. The problem is divided into three cases. Case 1 has first two objective functions, the case 2 considers last three objective functions and case 3 deals all the five objective functions. Intelligent optimization algorithms namely Multi-objective Genetic Algorithm (MOGA), Elitist Non-dominated Sorting Genetic Algorithm (NSGA-II) and Multi-objective Differential Evolution (MODE) are proposed to solve the problem. Normalized weighting objective functions method is used to select the best optimal solution from Pareto optimal front. Two multi-objective performance measures (solution spread measure (SSM) and ratio of non-dominated individuals (RNIs)) are used to evaluate the strength of the Pareto optimal fronts. Two more multi-objective performance measures namely optimizer overhead (OO) and algorithm effort are used to find the computational effort of MOGA, NSGA-II and MODE algorithms. The Pareto optimal fronts and results obtained from various techniques are compared and analyzed.     

Effective layer-based segmentation of compound images using morphology

Effective compound image compression algorithms require compound images to be first segmented into regions such as text, pictures and background to minimize the loss of visual quality of text during compression. In this paper, a new compound image segmentation algorithm based on the Mixed Raster Content model (MRC) of multilayer approach is proposed (foreground/mask/background). This algorithm first segments a compound image into different classes. Then each class is transformed to the three-layer MRC model differently according to the property of that class. Finally, the foreground and the background layers are compressed using JPEG 2000. The mask layer is compressed using JBIG2. The proposed morphological-based segmentation algorithm design a binary segmentation mask which partitions a compound image into different layers, such as the background layer and the foreground layer accurately. Experimental results show that it is more robust with respect to the font size, style, colour, orientation, and alignment of text in an uneven background. At similar bit rates, our MRC compression with the morphology-based segmentation achieves a much higher subjective quality and coding efficiency than the state-of-the-art compression algorithms, such as JPEG, JPEG 2000 and H.264/AVC-I.     

α‐Ketobenzothiazole Serine Protease Inhibitors of Aberrant HGF/c‐MET and MSP/RON Kinase Pathway Signaling in Cancer

Upregulation of the HGF and MSP growth‐factor processing serine endopeptidases HGFA, matriptase and hepsin is correlated with increased metastasis in multiple tumor types driven by c‐MET or RON kinase signaling. We rationally designed P1’ α‐ketobenzothiazole mechanism‐based inhibitors of these proteases. Structure–activity studies are presented, which resulted in the identification of potent inhibitors with differential selectivity. The tetrapeptide inhibitors span the P1–P1’ substrate cleavage site via a P1’ amide linker off the benzothiazole, occupying the S3’ pocket. Optimized inhibitors display sub‐nanomolar enzyme inhibition against one, two, or all three of HGFA, matriptase, and hepsin. Several compounds also have good selectivity against the related trypsin‐like proteases, thrombin and Factor Xa. Finally, we show that inhibitors block the fibroblast (HGF)‐mediated migration of invasive DU145 prostate cancer cells. In addition to prostate cancer, breast, colon, lung, pancreas, gliomas, and multiple myeloma tumors all depend on HGF and MSP for tumor survival and progression. Therefore, these unique inhibitors have potential as new therapeutics for a diverse set of tumor types.