4,516 research outputs found
Simulation of the deflected cutting tool trajectory in complex surface milling
Since industry is rapidly developing, either locally
or globally, manufacturers witness harder challenges due to
the growing competitivity. This urges them to better consider the four factors linked to production and output: quality, quantity, cost and price, quality being of course the most important factor which constitutes their main concern. Efforts will be concentrated—in this research—on improving the quality and securing more accuracy for a machined surface in ball-end milling. Quality and precision are two essential criteria in industrial milling. However, milling errors and imperfections, duemainly to the cutting tool deflection, hinder the full achieving of these targets. Our task, all along this paper, consists in studying and realizing the simulation of the deflected cutting tool trajectory, by using the methods which are available. In a future stage, and in the frame of a deeper
research, the simulation process will help to carry out the
correction and the compensation of the errors resulting from
the tool deflection. The corrected trajectory which is obtained by the method mirror will be sent to the machine. To achieve this goal, the next process consists—as a first step—in selecting a model of cutting forces for a ball-end mill. This allows to define—later on—the behavior of this tool, and the emergence of three methods namely the analytical model, the finite elements method, and the experimental method. It is possible to tackle the cutting forces simulation, all along the tool trajectory, while this latter is carrying out the sweeping of the part to be machined in milling and taking into consideration the cutting conditions, as well as the geography of the workpiece. A simulation of the deflected cutting tool trajectory dependent on the cutting forces has been realized
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Transfer and intra-articular expression of the IL-1Ra cDNA in human rheumatoid joints
Electron-Spin Excitation Coupling in an Electron Doped Copper Oxide Superconductor
High-temperature (high-Tc) superconductivity in the copper oxides arises from
electron or hole doping of their antiferromagnetic (AF) insulating parent
compounds. The evolution of the AF phase with doping and its spatial
coexistence with superconductivity are governed by the nature of charge and
spin correlations and provide clues to the mechanism of high-Tc
superconductivity. Here we use a combined neutron scattering and scanning
tunneling spectroscopy (STS) to study the Tc evolution of electron-doped
superconducting Pr0.88LaCe0.12CuO4-delta obtained through the oxygen annealing
process. We find that spin excitations detected by neutron scattering have two
distinct modes that evolve with Tc in a remarkably similar fashion to the
electron tunneling modes in STS. These results demonstrate that
antiferromagnetism and superconductivity compete locally and coexist spatially
on nanometer length scales, and the dominant electron-boson coupling at low
energies originates from the electron-spin excitations.Comment: 30 pages, 12 figures, supplementary information include
Comparative Evaluation of Light-Trap Catches, Electric Motor Mosquito Catches and Human Biting Catches of Anopheles in the Three Gorges Reservoir
The mosquito sampling efficiency of light-trap catches and electric motor mosquito catches were compared with that of human biting catches in the Three Gorges Reservoir. There was consistency in the sampling efficiency between light-trap catches and human biting catches for Anopheles sinensis (r = 0.82, P<0.01) and light-trap catches were 1.52 (1.35–1.71) times that of human biting catches regardless of mosquito density (r = 0.33, P>0.01), while the correlation between electric motor mosquito catches and human biting catches was found to be not statistically significant (r = 0.43, P>0.01) and its sampling efficiency was below that of human biting catches. It is concluded that light-traps can be used as an alternative to human biting catches of Anopheles sinensis in the study area and is a promising tool for sampling malaria vector populations
Profiling allele-specific gene expression in brains from individuals with autism spectrum disorder reveals preferential minor allele usage.
One fundamental but understudied mechanism of gene regulation in disease is allele-specific expression (ASE), the preferential expression of one allele. We leveraged RNA-sequencing data from human brain to assess ASE in autism spectrum disorder (ASD). When ASE is observed in ASD, the allele with lower population frequency (minor allele) is preferentially more highly expressed than the major allele, opposite to the canonical pattern. Importantly, genes showing ASE in ASD are enriched in those downregulated in ASD postmortem brains and in genes harboring de novo mutations in ASD. Two regions, 14q32 and 15q11, containing all known orphan C/D box small nucleolar RNAs (snoRNAs), are particularly enriched in shifts to higher minor allele expression. We demonstrate that this allele shifting enhances snoRNA-targeted splicing changes in ASD-related target genes in idiopathic ASD and 15q11-q13 duplication syndrome. Together, these results implicate allelic imbalance and dysregulation of orphan C/D box snoRNAs in ASD pathogenesis
Vectorlike Confinement at the LHC
We argue for the plausibility of a broad class of vectorlike confining gauge
theories at the TeV scale which interact with the Standard Model predominantly
via gauge interactions. These theories have a rich phenomenology at the LHC if
confinement occurs at the TeV scale, while ensuring negligible impact on
precision electroweak and flavor observables. Spin-1 bound states can be
resonantly produced via their mixing with Standard Model gauge bosons. The
resonances promptly decay to pseudo-Goldstone bosons, some of which promptly
decay to a pair of Standard Model gauge bosons, while others are charged and
stable on collider time scales. The diverse set of final states with little
background include multiple photons and leptons, missing energy, massive stable
charged particles and the possibility of highly displaced vertices in dilepton,
leptoquark or diquark decays. Among others, a novel experimental signature of
resonance reconstruction out of massive stable charged particles is
highlighted. Some of the long-lived states also constitute Dark Matter
candidates.Comment: 33 pages, 6 figures. v4: expanded discussion of Z_2 symmetry for
stability, one reference adde
An antibody-based biomarker discovery method by mass spectrometry sequencing of complementarity determining regions
Autoantibodies are increasingly used as biomarkers in the detection of autoimmune disorders and cancer. Disease specific antibodies are generally detected by their binding to specific antigens. As an alternative approach, we propose to identify specific complementarity determining regions (CDR) of IgG that relate to an autoimmune disorder or cancer instead of the specific antigen(s). In this manuscript, we tested the technical feasibility to detect and identify CDRs of specific antibodies by mass spectrometry. We used a commercial pooled IgG preparation as well as purified serum IgG fractions that were spiked with different amounts of a fully human monoclonal antibody (adalimumab). These samples were enzymatically digested and analyzed by nanoLC Orbitrap mass spectrometry. In these samples, we were able to identify peptides derived from the CDRs of adalimumab. These peptides could be detected at an amount of 110 attomole, 5 orders of magnitude lower than the total IgG concentration in these samples. Using higher energy collision induced dissociation (HCD) fragmentation and subsequent de novo sequencing, we could successfully identify 50% of the detectable CDR peptides of adalimumab. In addition, we demonstrated that an affinity purification with anti-dinitrophenol (DNP) monoclonal antibody enhanced anti-DNP derived CDR detection in a serum IgG background. In conclusion, specific CDR peptides could be detected and sequenced at relatively low levels (attomole-femtomole range) which should allow the detection of clinically relevant CDR peptides in patient samples
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