Flight Maneuver of a Damselfly with Phase Modulation of the Wings

Synopsis We developed a numerical model for four-wing self-propulsion to calculate effectively the flight velocity generated with varied wing motions, which satisfactorily verified biological experiments. Through this self-propulsion model, we analyzed the flight velocity of a damselfly (Matrona cyanoptera) at varied phases. The results show that after phase modulation of the wings, the aerodynamic performance of the forewing (FW) is affected by the incoming flow and an effective angle of attack, whereas that of the hindwing (HW) is dominated by the vortex interaction and induced flow generated by the shed vortex of the FW. Cooperating with the flow interaction, in stable flight, the HW in the lead phase has a larger vertical velocity, whereas the FW in the lead phase has a larger horizontal velocity. Regarding the aerodynamic efficiency, the FW in the lead phase has greater horizontal efficiency, whereas the HW in the lead phase has greater vertical efficiency; the overall efficiency does not vary with the phase. This work interprets that a dragonfly adopts the HW in the lead phase to generate a larger lift, thus supporting the larger body weight, whereas a damselfly adopts the FW in the lead phase to have a greater forward velocity, which can supplement the lack of flapping frequency.

Individual & Collective Human Intelligence in Drug Design: Evaluating the Search Strategy

<p>In recent years, individual and collective human intelligence, defined as the knowledge, skills, reasoning and intuition of individuals and groups, have been used in combination with computer algorithms to solve complex scientific problems. Such approach was successfully used in different research fields such as: structural biology, comparative genomics, macromolecular crystallography and RNA design. Herein we describe an attempt to use a similar approach in small-molecule drug discovery, specifically to drive search strategies of <i>de novo</i> drug design. This is assessed with a case study that consists of a series of public experiments in which participants had to explore the huge chemical space <i>in silico</i> to find predefined compounds by designing molecules and analyzing the score associate with them. Such a process may be seen as an instantaneous surrogate of the classical design-make-test cycles carried out by medicinal chemists during the drug discovery hit to lead phase but not hindered by long synthesis and testing times. The objectives of this case study are to give the first insights towards: the assessment of human intelligence in chemical space exploration problems; compare the performance of individual and collective human intelligence in such a problems; and also contrast some human and artificial intelligence achievements in<em> </em><em><i>de novo</i></em> drug design.</p>

FEP+ calculations predict a stereochemical SAR switch for first-in-class indoline NIK inhibitors for multiple myeloma

In the search for first-in-class NIK inhibitors for multiple myeloma, we discovered an azaindoline hit class generated from a biochemical NIK autophosphorylation high-throughput screening assay which was optimized to the final cyanoindoline compound class. During the hit-to-lead phase, a prominent stereochemical SAR switch was observed which was accurately predicted by in silico FEP+ calculations. Crystallographic and computational analysis showed that for both stereoisomers comparable contacts, both in nature and number, could be formed by the switching hydroxyl group, making this system particularly interesting from an interaction energy viewpoint. We provide a detailed analysis of our FEP+ and WaterMap calculations and show how this type of computational chemistry methods are useful during hit-to-lead and lead optimization phases.

New Catalytic Approaches for Producing Alternative to MTBE Additives for Reformulation of Gasoline

Due to the lead phase out that began in 1973, refiners had to replace the octane loss in gasoline. For this purpose, oxygenates and highly branched alkylates will play a major role as gasoline additives because they have relatively high octane ratings. Methyl tertiary-butyl ether (MTBE) is the oxygenate as a gasoline additive the most widely used nowadays in most of the countries in the world. It is used to raise octane levels, enhance engine performance, improve combustion efficiency and to reduce emissions of air pollutants such as carbon monoxide and hydrocarbons.

Microstructure and wear property of spray formed high leaded bronze

In this research, Cu-9Pb high leaded bronze were prepared by spray forming. The microstructure and wear properties of this bronze alloy were systematically investigated. The results show that although the hardness of spray formed alloy was not increased comparing with the cast alloy, it still presented a lower wear rate and a lower friction coefficient in dry sliding wear tests as shallower grooves and more lubricating films were observed in the spray formed bronze (BSF14). Spray forming also refined the lead phase microstructure of Cu-9Pb bronze and improved its wear properties.

Recovery of Silver and Lead through Reprocessing of Lead Tailings from Yunnan

Properties of the ore were studied by chemical analysis and Lead phase. Research shows that the lead tailings contains 15.47 g/t of silver and 0.62% of lead, lead minerals are mainly Galena, Anglesite and Finnemanite, Silver minerals and galena symbiosis, besides, gangue minerals are mainly quartz. Based on properties of the tailings, flotation feasibility pilot study was conducted. Results show that excellent test indexes that a Ag grade of 137.09 g/t with a Ag recovery of 55.27% and a Pb grade of 5.85% with a Pb recovery of 60.35% were obtained under the used process and reagent system conditions.