Thrust and torque response for drilling titanium and carbon composite sandwich materials [abstract]

Abstract only availableExperiments were conducted based upon previous research conducted by El-Gizawy and Khasawneh [1] to determine the time response of thrust force and torque correlated to a simple drilling procedure through carbon fiber reinforced epoxy (IM7/997-3) composite material over 6Al-4V titanium alloy (AB1) sheets. The experiments measured the time response with a thrust and torque sensor, data acquisition system and CNC drilling machine. The research was used to locate points of interest among the previous statistical setup. Three-dimensional surfaces were analyzed to determine the drilling parameters that cause the highest force and torque in the CNC spindle (and, therefore, the drill bit) and the lowest force and torque, within the range available with the CNC used in the experimental setup. The experimental holes were also analyzed via surface profilometer and coordinate measurement probe to obtain surface roughness and dimensional accuracy measurements. The data indicates that the parameters that cause lower force and torque are preferable for dimensional accuracy in the titanium as well as for surface roughness, and tool life.College of Engineering Undergraduate Research Optio

Structural and dynamic determinants for highly selective RET kinase inhibition reveal cryptic druggability.

The structural and dynamic determinants for highly selective RET kinase inhibition are poorly understood. Here we demonstrate by applying an integrated structural, computational and biochemical approach that the druggability landscape of the RET active site is determined by the conformational setting of the ATP-binding (P-) loop and its coordination with the αC helix. Open and intermediate P-loop structures display additional druggable vulnerabilities within the active site that were not exploited by first generation RET inhibitors. We identify a cryptic pocket adjacent to the catalytic lysine formed by K758, L760, E768 and L772, that we name the post-lysine pocket, with higher druggability potential than the adenine-binding site and with important implications in the regulation of phospho-tyrosine kinase activity. Crystal structure and simulation data show that the binding mode of highly-selective RET kinase inhibitors LOXO-292 and BLU-667 is controlled by a synchronous open P-loop and αC-in configuration that allows accessibility to the post-lysine pocket. Molecular dynamics simulation show that these inhibitors efficiently occupy the post-lysine pocket with high stability through the simulation time-scale (300 ns), with both inhibitors forming hydrophobic contacts in the pocket further stabilized by pi-cation interactions with the catalytic K758. Engineered mutants targeting the post-lysine pocket impact on inhibitor binding and sensitivity, as well as RET tyrosine kinase activity. The identification of the post-lysine pocket as a cryptic druggable vulnerability in the RET kinase and its exploitation by second generation RET inhibitors has important implications for future drug design and the development of personalized therapies for patients with RET-driven cancers.We thank the Centro Nacional de Investigaciones Oncológicas (CNIO), which is supported by the Instituto de Salud Carlos III and recognized as a “Severo Ochoa” Centre of Excellence (ref. CEX2019-000891-S, awarded by MCIN/AEI/ 10.13039/501100011033) for core funding and supporting this study. This work was further supported by projects: BFU2017-86710-R funded by MCIN/ AEI /10.13039/501100011033 and ERDF “A way of making Europe”, PID2020-117580RB-I00 funded by MCIN/ AEI /10.13039/501100011033, RYC-2016-1938 funded by MCIN/AEI /10.13039/501100011033 and ESF “Investing in your future”, and a Marie Curie WHRI-ACADEMY International grant (number 608765) to IP-M and a CNIO-Friends predoctoral Carmen Gloria Bonnet Fellowship to MAS.N

Design of an electrical system for swaging targets in the production of molybdenum-99 [abstract]

Abstract only availableMolybdenum-99 is used all over the world to make technetium-99m for use in medical and research fields. The Molybdenum-99 is made by placing low enriched uranium foil in a reactor and allowing it to be irradiated. In order to irradiate the uranium safely, an aluminum target must be assembled to surround the foil. The current process for making these targets is to use a manually powered swaging device. It works by pulling a plug through an aluminum tube assembly which contains the uranium foil. The plug plastically deforms the inner tube and seals the foil inside. This process is time consuming and requires a lot of strength. The idea of using an electrically driven system to swag the tubes was investigated. The required system was analyzed to determine the forces, torque and power needed. A detailed design of the driving system was established and necessary standard components were selected. The new design concept was constructed in a three dimensional solid presentation and in two dimensional drawings. Assembly analysis of different components was conducted in order to assure accurate mating relations among different components

Sunflower oil-based hyperbranched alkyd/spherical ZnO nanocomposite modeling for mechanical and anticorrosive applications

Approaches for designing advanced nanomaterials with hyperbranched architectures and lack of volatile organic content (VOC) have attracted considerable attention. In this study, eco-friendly hyperbranched alkyd resins for mechanical and anticorrosive coatings with high solid content were successfully synthesized based on sunflower oil (SFO) via a polyesterification approach. These resins are characterized by energy-efficient polymer synthesis, lack of gelation properties, high functionality, and low viscosity. A chemical precipitation process was used to fabricate zinc oxide (ZnO) spherical nanostructures with controlled diameters and morphologies. A series of conformal, novel, low-cost SFO-based hyperbranched alkyd/spherical ZnO nanocomposites were fabricated through an ex situ method. Various nanofiller concentrations were distributed to establish synergetic effects on the micro-nano binary scale performance of the materials. The features of the nanocomposites, including the molecular weight, acid and hydroxyl values of the prepared alkyd resins, were concomitantly assessed through various standard tests. The nanocomposites were also subjected to various tests to determine their surface adhesion and mechanical properties, such as impact, T-bending, crosscut, and abrasion resistance tests. Furthermore, the physico-mechanical properties, anticorrosive behavior, thermal stabilities and cellular cytotoxicities of the fabricated materials were assessed. The anticorrosive features of the nanocomposites were investigated through salt spray tests in 5 wt% NaCl. The results indicate that well-dispersed ZnO nanospheres (0.5%) in the interior of the hyperbranched alkyd matrix improve the durability and anticorrosive attributes of the composites; thus, they exhibit potential applications in eco-friendly surface coatings

Synthesis, Characterization, and Biological Activity of N1-Methyl-2-(1H-1,2,3-Benzotriazol-1-y1)-3-Oxobutan- ethioamide Complexes with Some Divalent Metal (II) Ions

A new series of Zn2+, Cu2+, Ni2+, and Co2+ complexes of N1-methyl-2-(1H-1,2,3-benzotriazol-1-yl)-3-oxobutanethioamide (MBOBT), HL, has been synthesized and characterized by different spectral and magnetic measurements and elemental analysis. IR spectral data indicates that (MBOBT) exists only in the thione form in the solid state while 13C NMR spectrum indicates its existence in thione and thiole tautomeric forms. The IR spectra of all complexes indicate that (MBOBT) acts as a monobasic bidentate ligand coordinating to the metal(II) ions via the keto-oxygen and thiolato-sulphur atoms. The electronic spectral studies showed that (MBOBT) bonded to all metal ions through sulphur and nitrogen atoms based on the positions and intensity of their charge transfer bands. Furthermore, the spectra reflect four coordinate tetrahedral zinc(II), tetragonally distorted copper(II), square planar nickel(II), and cobalt(II) complexes. Thermal decomposition study of the complexes was monitored by TG and DTG analyses under N2 atmosphere. The decomposition course and steps were analyzed and the activation parameters of the nonisothermal decomposition are determined. The isolated metal chelates have been screened for their antimicrobial activities and the findings have been reported and discussed in relation to their structures

Theories, Hypothesis and Rules for Morphology Transition Engineering of 1D, 2D and 3D Nanomaterials

Most of the chemical and physical properties of nanomaterials vary remarkably according to their size, shape, and structure. Thus morphology is a crucial parameter that controls the properties and functionality of materials. On the basis of Abdelmohsen et al.’s theories and hypothesis, which are theory for morphology transition engineering (ATMTE), theory for morphology engineering of solid compounds (ATMESC), and hypothesis for engineering of micro- and nanostructures (AHEMNS), novel approach was modified for fabricating one-, two-, and three-dimensional hybrid nanomaterials, such as hybrid ZnO nanosheets (38–150 nm), hybrid ZnO nanorods, hybrid nanocomposites, and hierarchical hybrid Cu2O nanostructures. In addition, by the help of this novel method, the fabrication of metal-oxidene (one/few atoms thick layer of metal oxides) is assumed and hybrid ZnO thin film that is expected to have extraordinary physicochemical properties. A series of selection rules and morphology engineering rules are discussed. Throughout this chapter, we will come across this novel approach as a promising technique for nanofabrication and discuss the suggested mechanisms for the evolution process during fabrication of nanomaterials. By the help of this method, we have fabricated 1D, 2D and 3D nanomaterials that are expected to have potential use for energy, catalysis, biomedical, and other applications

Evaluation of selective peripheral neurotomies in the treatment of refractory lower limb spasticity in adults

Background: ‘‘Selective peripheral neurotomies” (SPNs) are indicated for the treatment of refractory focal and multifocal spasticity of lower limbs in adults.Objective: To evaluate the surgical results of selective peripheral neurotomies in 20 adult patients who had refractory focal & multifocal spasticity of the lower limbs, follow up period of one year.Patients and Methods: Prospective study included 20 adult patients who had refractory spasticity of the lower limbs. Preoperative evaluation for muscle tone using Modified Ashworth Score (MAS), muscle power using Medical Research Council Scale (MRCS), functional assessment using Oswestry Functional Scale (OFS) and Range Of Motion (ROM) using manual goniometry were done for all patients. All cases underwent surgery in the form of SPN of tibial, obturator, sciatic and/or femoral nerves. Follow up of the patients was done at 10th day, 3, 6 months and one year postoperatively.Results: The mean age of patients was 31.35 ± 12.42 years. There were statistically significant improvement of muscle tone, muscle power, functional assessment and range of motion between preoperative and one year postoperative values. Improvement of the muscle tone was from a preoperative Mean ± SD of 3.60 ± 0.68 on MAS to a postoperative 2.30 ± 0.86 at one year, improvement of muscle power on MRCS was from preoperative Mean ± SD 3.75 ± 1.08 to postoperative 4.08 ± 0.69 at one year, There was a functional improvement from a preoperative Mean ± SD of 3.0 ± 0.73 on OFS to 3.60 ± 0.60 at one year postoperatively. Also, there was a significant improvement between preoperative ROM Mean ± SD 61.25 ± 15.29 and one year postoperatively 72.25 ± 12.19.Conclusions: Selective peripheral neurotomies could effectively improve muscle tone, muscle power, functional performance & range of motion in patients with refractory focal and multifocal spasticity in the lower limbs.Keywords: Selective peripheral neurotomies, Spasticity, Neuroablative surgeries, Functional neurosurger

Longitudinal Hierarchy Co3O4 Mesocrystals with High-dense Exposure Facets and Anisotropic Interfaces for Direct-Ethanol Fuel Cells

Novel electrodes are needed for direct ethanol fuel cells with improved quality. Hierarchical engineering can produce catalysts composed of mesocrystals with many exposed active planes and multi-diffused voids. Here we report a simple, one-pot, hydrothermal method for fabricating Co 3 O 4 /carbon/substrate electrodes that provides control over the catalyst mesocrystal morphology (i.e., corn tubercle pellets or banana clusters oriented along nanotube domains, or layered lamina or multiple cantilevered sheets). These morphologies afforded catalysts with a high density of exposed active facets, a diverse range of mesopores in the cage interior, a window architecture, and vertical alignment to the substrate, which improved efficiency in an ethanol electrooxidation reaction compared with a conventional platinum/carbon electrode. On the atomic scale, the longitudinally aligned architecture of the Co 3 O 4 mesocrystals resulted in exposed low- and high-index single and interface surfaces that had improved electron transport and diffusion compared with currently used electrodes