A method to improve the quality of rock preparation for extraction with emulsion explosives in open-pit mines with high benches

Increasing the production capacity of open-pit and strip mines while ensuring the efficiency of the mining enterprise can be achieved through enhancing the quality of rock preparation prior to excavation. The use of emulsion explosives and the transition to the high-bench technology can reduce the cost of mining operations by optimizing the drilling and blasting parameters. The article reviews methods to improve the efficiency of rock preparation for extraction based on the applicable scientific and methodological principles and it proposes a method to regulate the density of emulsion explosives. Schemes are presented for calculation of drilling and blasting parameters when implementing technical measures aimed at improving the blasting quality through rock preparation for extraction in conditions of overburden and mining operations with bench height of 15 m and higher. Parameters of drilling and blasting operations on high benches are justified with differentiation of the charge density along the length of the blast hole by controlling the delivery of the gas-generating additive. A simulation has been performed and the results of pilot tests of the emulsion explosive charge density control at the Ural deposits are presented.

Integrated Control of Aedes Aegypti With Parasitic Nematodes, Biological Control Agents, Chemical Insecticides and Plant Essential Oil

Aedes aegypti can transmit dengue fever, yellow fever, Chikungunya fever, Zika virus disease and vector density control is the most effective way to prevent these infectious diseases. However, the extensive use of chemical pesticides has caused a series of problems, such as environmental pollution, killing non-target organisms and so on. In this study, a parasitic nematode, Romanomermis wuchangensis was used in the larviciding evaluation of Ae. aegypti, while the activity of four chemical insecticides and biological control agents were tested. Besides, Mentha haplocalyx essential oil was isolated and its olfactory physiological function with OBP1 protein of Ae. aegypti antenna was measured by the prokaryotic expression and fluorescence competitive binding assay. Compared with the control group, R. wuchangensis indicated high efficiency and environmental friendliness in the control of Ae. aegypti. After the second instar larvae were parasitized, the mortality of two treatment groups exceeded 75%. Compared to control group, the quantitative real-time PCR analysis results demonstrated that SOD, POD and CAT genes had obvious high expression levels in the nematodes parasitic groups. The antioxidant enzyme test results also exhibited obvious difference of SOD, CAT and POD during the nematode parasitic period. Besides, Bacillus thuringiensis (Bti) and chemical insecticide experimental results also showed great insecticidal efficacy against mosquito larvae. Five chemical components including Menthol, Pinene, Limonene, Isopulegol and Pulegone were identified from M. haplocalyx and exhibited great binding ability with AaegOBP1 protein. Present results illustrated that the integrated application of these various mosquito vector control methods in the future has broad prospects.

Induction Heating in Domestic Cooking and Industrial Melting Applications: A Systematic Review on Modelling, Converter Topologies and Control Schemes

In the current scenario, power electronic device-based induction heating (IH) technologies are widely employed in domestic cooking, industrial melting and medical applications. These IH applications are designed using different converter topologies, modulation and control techniques. This review article mainly focuses on the modelling of half-bridge series resonant inverter, electrical and thermal model of IH load. This review also analyses the performance of the converter topologies based on the power conversion stages, switching frequency, power rating, power density, control range, modulation techniques, load handling capacity and efficiency. Moreover, this paper provides insight into the future of IH application, with respect to the adaptation of wide band-gap power semiconductor materials, multi-output topologies, variable-frequency control schemes with minimum losses and filters designed to improve source-side power factor. With the identified research gap in the literature, an attempt has also been made to develop a new hybrid modulation technique, to achieve a wide range of power control with high efficiency. A 100 W full-bridge inverter prototype is realised both in simulation and hardware, with various modulation schemes using a PIC16F877A microcontroller. The results are compared with existing techniques and the comparisons reveal that the proposed scheme is highly viable and effective for the rendered applications.

Adverse effect of Canaglifloxacin on bone is reversed by Puerariae radix in rat model of diabetics

The root of Pueraria labata, Puerariae radix(PR), a leguminous plant that grows wild, is one of the first and most significant basic herbs used in traditional medicine for a variety of therapeutic uses. PR is high in isoflavonoids including daidzein and genistein, which have been shown to protect against bone loss caused by oestrogen insufficiency. In an osteoporotic animal model, soybean isoflavones have been shown to reduce bone loss. CGF (canagliflozin) appears to raise the risk of fractur. In diabetic rats, the potential function of PR in reversing CGFinduced bone loss was investigated. A rat model was used to investigate the effects of Puerariae radix extract (PRE) on blood glucose, HBA1C levels, and bone mineral density. Control group (vehicle therapy), Diabetic group, `PRE group, Canagliflozin (CGF), and CGF +PRE group were all made up of six Wistar albino rats. Each medication was given by gastric gavage once a day for 35 days. PRE treatment increased bone mass substantially when compared to normal controls. This suggests that PRE might be developed as an alternative therapy for osteoporosis caused by anti-diabetic drugs. Keywords: Puerariae radix, Diabetic osteoporosis, streptozotocin, Canagliflozin.