Scaling differences between large interplate and intraplate earthquakes

A study of large intraplate earthquakes with well-determined source parameters shows that these earthquakes obey a scaling law similar to large interplate earthquakes, in which M_0 ∝ L^2 or u = αL, where L is rupture length and u is slip. In contrast to interplate earthquakes, for which α ≈ 1 × 10^(−5), for for the intraplate events α ≈ 6 × 10^(−5), which implies that these earthquakes have stress drops about 6 times higher than interplate events. This result is independent of focal mechanism type. This implies that intraplate faults have a higher frictional strength than do plate boundaries, and hence that faults are velocity or slip weakening in their behavior. This factor may be important in producing the concentrated deformation that creates and maintains plate boundaries

Strange nucleon electromagnetic form factors from lattice QCD

We evaluate the strange nucleon electromagnetic form factors using an ensemble of gauge configurations generated with two degenerate maximally twisted mass clover-improved fermions with mass tuned to approximately reproduce the physical pion mass. In addition, we present results for the disconnected light quark contributions to the nucleon electromagnetic form factors. Improved stochastic methods are employed leading to high-precision results. The momentum dependence of the disconnected contributions is fitted using the model-independent z-expansion. We extract the magnetic moment and the electric and magnetic radii of the proton and neutron by including both connected and disconnected contributions. We find that the disconnected light quark contributions to both electric and magnetic form factors are non-zero and at the few percent level as compared to the connected. The strange form factors are also at the percent level but more noisy yielding statistical errors that are typically within one standard deviation from a zero value.Comment: 10 pages, 11 figure

3D printing part orientation optimization: discrete approximation of support volume

In three-dimensional (3D) printing, due to the geometry of most parts, it is necessary to use extra material to support the manufacturing process. This material must be discarded after printing, so its reduction is essential to minimize manufacturing time and cost. An important parameter that must be defined before starting the printing process is the part orientation, which has repercussions on the quality, deposition path, and post-processing among others. Usually, the user sets up this parameter arbitrarily, so this paper takes advantage of it on optimization techniques and proposes an approximation of the volume be covered by the support material, which depends directly on the angle of the part to be printed and its geometry. Among mono-objectives optimization strategies, this work focuses on five of them. Their performance is compared by two metrics: support volume and execution time. Then, the best result is compared with commercial software

The Right to a Safe and Healthy Birth

The right to a safe and healthy birth is included in the declaration of human rights- the intrinsic allowances that humans are obligated to be protected by on a global scale. These rights, however, for some pregnant women have been submersed by lack of transportation, education and skilled birth attendants. Financial constraints and difficulty in obtaining adequate healthcare are also issues of concern. A review of literature pertaining to three different countries, the United States, China and India will be examined in light of safe and healthy birthing techniques for women worldwide. These countries were chosen due to their diverse injustice issues as it pertains to birthing rights. Education and advocacy efforts in relation to reproductive rights on a global scale will be discussed. Review of the literature not only reveals grave injustices for women and children but it also illuminates ways in which individuals can get involved to help promote the right to a safe and healthy birth. Several movements will be highlighted in order to provide the audience with practical advocacy, education, and relief effort implementations

Automated carotid endarterectomy surgery using a low cost remodelled industrial robotic arm

No description supplie

Asymptotically Hyperbolic Non Constant Mean Curvature Solutions of the Einstein Constraint Equations

We describe how the iterative technique used by Isenberg and Moncrief to verify the existence of large sets of non constant mean curvature solutions of the Einstein constraints on closed manifolds can be adapted to verify the existence of large sets of asymptotically hyperbolic non constant mean curvature solutions of the Einstein constraints.Comment: 19 pages, TeX, no figure

Nucleon axial, tensor and scalar charges and σ\sigma-terms in lattice QCD

We determine the nucleon axial, scalar and tensor charges within lattice Quantum Chromodynamics including all contributions from valence and sea quarks. We analyze three gauge ensembles simulated within the twisted mass formulation at approximately physical value of the pion mass. Two of these ensembles are simulated with two dynamical light quarks and lattice spacing $a=0.094$~fm and the third with $a=0.08$~fm includes in addition the strange and charm quarks in the sea. After comparing the results among these three ensembles, we quote as final values our most accurate analysis using the latter ensemble. For the nucleon isovector axial charge we find $1.286(23)$ in agreement with the experimental value. We provide the flavor decomposition of the intrinsic spin $\frac{1}{2}\Delta\Sigma^q$ carried by quarks in the nucleon obtaining for the up, down, strange and charm quarks $\frac{1}{2}\Delta\Sigma^{u}=0.431(8)$, $\frac{1}{2}\Delta\Sigma^{d}=-0.212(8)$, $\frac{1}{2}\Delta\Sigma^{s}=-0.023(4)$ and $\frac{1}{2}\Delta\Sigma^{c}=-0.005(2)$, respectively. The corresponding values of the tensor and scalar charges for each quark flavor are also evaluated providing valuable input for experimental searches for beyond the standard model physics. In addition, we extract the nucleon $\sigma$-terms and find for the light quark content $\sigma_{\pi N}=41.6(3.8)$~MeV and for the strange $\sigma_{s}=45.6(6.2)$~MeV. The y-parameter that is used in phenomenological studies we find $y=0.078(7)$.Comment: Expanded version as accepted in Phys. Rev. D.20 pages and 20 figure