The Rockefeller Foundation; a Review for 1939 (Book Review)

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Mine and me: exploring the neural basis of object ownership.

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Bio-inks for 3D bioprinting : recent advances and future prospects

In the last decade, interest in the field of three-dimensional (3D) bioprinting has increased enormously. 3D bioprinting combines the fields of developmental biology, stem cells, and computer and materials science to create complex bio-hybrid structures for various applications. It is able to precisely place different cell types, biomaterials and biomolecules together in a predefined position to generate printed composite architectures. In the field of tissue engineering, 3D bioprinting has allowed the study of tissues and organs on a new level. In clinical applications, new models have been generated to study disease pathogenesis. One of the most important components of 3D bio-printing is the bio-ink, which is a mixture of cells, biomaterials and bioactive molecules that creates the printed article. This review describes all the currently used bio-printing inks, including polymeric hydrogels, polymer bead microcarriers, cell aggregates and extracellular matrix proteins. Amongst the polymeric components in bio-inks are: natural polymers including gelatin, hyaluronic acid, silk proteins and elastin; and synthetic polymers including amphiphilic block copolymers, PEG, poly(PNIPAAM) and polyphosphazenes. Furthermore, photocrosslinkable and thermoresponsive materials are described. To provide readers with an understanding of the context, the review also contains an overview of current bio-printing techniques and finishes with a summary of bio-printing applications

Report of the President [of the Carnegie Corporation] (Book Review)

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Bathymetry Based Modeling of Subaxial Magma Flows Under the Mid-Atlantic Ridge, 0 to 30° N

Fracture patterns of the Mid-Atlantic Ridge (MAR) provide evidence of tectonic forces related to divergence and magma upwelling at the ridge axis. In this study, we focus on the MAR from 0 to 30° N, where the N-S ridge exhibits slow spreading rates (2-4 cm/yr) and pronounced axial topography. Ridge segments and transform faults identified in bathymetry data were analyzed for strike orientation and axial depth profiles. Azimuths of transform faults and ridge segments exhibit increasing clockwise rotation with latitude, and all have left lateral displacement. Bathymetric sampling along ridge segments occurred at 9 km intervals with 20 km sampling radii, producing axial lithostatic pressure gradients. One-dimensional magma flows parallel to the ridge axis at 10 and 50 km depths were modeled using Darcy’s law based on published parameters and calculated gradients. Subaxial magma velocities of up to 4 cm/yr were predicted for horizontal flow at depth and are comparable in magnitude to upwelling rates in published literature. Average flow magnitudes (n = 422) within the melt generation region are predicted at 0.8 and 0.2 cm/yr for 10 and 50 km depths respectively. Flow velocities up to five times higher are expected with this model in the high-porosity boundary layer below the solidus. The Coriolis parameter would affect the movement of the flows predicted by our model and may be linked to rotational patterns observed at the MAR. Future research of magma migration below divergent margins would benefit from incorporating axial lithostatic load variations as a driver of flow

Trained immunity or tolerance : opposing functional programs induced in human monocytes after engagement of various pattern recognition receptors

Article Accepted Date: 29 January 2014. ACKNOWLEDGMENTS D.C.I. received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement HEALTH-2010-260338 (“Fungi in the setting of inflammation, allergy and autoimmune diseases: translating basic science into clinical practices” [ALLFUN]) (awarded to M.G.N.). M.G.N. and J.Q. were supported by a Vici grant of the Netherlands Organization of Scientific Research (awarded to M.G.N.). This work was supported, in part, by National Institutes of Health grant GM53522 to D.L.W. N.A.R.G. was supported by the Wellcome Trust.Peer reviewedPublisher PD

Sensitivity and back-action in charge qubit measurements by a strongly coupled single-electron transistor

We consider charge-qubit monitoring (continuous-in-time weak measurement) by a single-electron transistor (SET) operating in the sequential-tunneling regime. We show that commonly used master equations for this regime are not of the Lindblad form that is necessary and sufficient for guaranteeing valid physical states. In this paper we derive a Lindblad-form master equation and a corresponding quantum trajectory model for continuous measurement of the charge qubit by a SET. Our approach requires that the SET-qubit coupling be strong compared to the SET tunnelling rates. We present an analysis of the quality of the qubit measurement in this model (sensitivity versus back-action). Typically, the strong coupling when the SET island is occupied causes back-action on the qubit beyond the quantum back-action necessary for its sensitivity, and hence the conditioned qubit state is mixed. However, in one strongly coupled, asymmetric regime, the SET can approach the limit of an ideal detector with an almost pure conditioned state. We also quantify the quality of the SET using more traditional concepts such as the measurement time and decoherence time, which we have generalized so as to treat the strongly responding regime.Comment: About 11 pages, 6 figures. Changes in v2: we made general improvements to the manuscript including, but not limited to(!), the removal of one reference, and modification of the footnote

Short-distance matrix elements for D0-meson mixing from Nf=2+1 lattice QCD

We calculate in three-flavor lattice QCD the short-distance hadronic matrix elements of all five ΔC=2 four-fermion operators that contribute to neutral D-meson mixing both in and beyond the Standard Model. We use the MILC Collaboration’s Nf=2+1 lattice gauge-field configurations generated with asqtad-improved staggered sea quarks. We also employ the asqtad action for the valence light quarks and use the clover action with the Fermilab interpretation for the charm quark. We analyze a large set of ensembles with pions as light as lattice gauge-field configurations generated with asqtad-improved staggered sea quarks. We also employ the asqtad action for the valence light quarks and use the clover action with the Fermilab interpretation for the charm quark. We analyze a large set of ensembles with pions as light as Mπ ≈ 180 MeV and lattice spacings as fine as a ≈ 0.045 fm, thereby enabling good control over the extrapolation to the physical pion mass and continuum limit. We obtain for the matrix elements in the MS−NDR scheme using the choice of evanescent operators proposed by Beneke et al., evaluated at 3 GeV, ⟨D0|Oi|¯D0⟩ = {0.0805(55)16),−0.1561(70)(31), 0.0464(31)(9), 0.2747(129)(55), 0.1035(71)(21)} GeV4 (i=1–5). The errors shown are from statistics and lattice systematics, and the omission of charmed sea quarks, respectively. To illustrate the utility of our matrix-element results, we place bounds on the scale of CP-violating new physics in D0 mixing, finding lower limits of about 10–50×103 TeV for couplings of O(1). To enable our results to be employed in more sophisticated or model-specific phenomenological studies, we provide the correlations among our matrix-element results. For convenience, we also present numerical results in the other commonly used scheme of Buras, Misiak, and Urban

B(s)0B^0_{(s)}-mixing matrix elements from lattice QCD for the Standard Model and beyond

We calculate---for the first time in three-flavor lattice QCD---the hadronic matrix elements of all five local operators that contribute to neutral $B^0$- and $B_s$-meson mixing in and beyond the Standard Model. We present a complete error budget for each matrix element and also provide the full set of correlations among the matrix elements. We also present the corresponding bag parameters and their correlations, as well as specific combinations of the mixing matrix elements that enter the expression for the neutral $B$-meson width difference. We obtain the most precise determination to date of the SU(3)-breaking ratio $\xi = 1.206(18)(6)$, where the second error stems from the omission of charm sea quarks, while the first encompasses all other uncertainties. The threefold reduction in total uncertainty, relative to the 2013 Flavor Lattice Averaging Group results, tightens the constraint from $B$ mixing on the Cabibbo-Kobayashi-Maskawa (CKM) unitarity triangle. Our calculation employs gauge-field ensembles generated by the MILC Collaboration with four lattice spacings and pion masses close to the physical value. We use the asqtad-improved staggered action for the light valence quarks, and the Fermilab method for the bottom quark. We use heavy-light meson chiral perturbation theory modified to include lattice-spacing effects to extrapolate the five matrix elements to the physical point. We combine our results with experimental measurements of the neutral $B$-meson oscillation frequencies to determine the CKM matrix elements $|V_{td}| = 8.00(34)(8) \times 10^{-3}$, $|V_{ts}| = 39.0(1.2)(0.4) \times 10^{-3}$, and $|V_{td}/V_{ts}| = 0.2052(31)(10)$, which differ from CKM-unitarity expectations by about 2$\sigma$. These results and others from flavor-changing-neutral currents point towards an emerging tension between weak processes that are mediated at the loop and tree levels.Comment: 75 pp, 17 figs. Ver 2 fixes typos; corrects mistakes resulting in slight changes to results, correlation matrices; updates decay constants to agree with recent PDG update; corrects uncertainties for tree-level CKM matrix elements used in comparison, slightly reducing tensions; includes additional analyses that support mostly-nonperturbative matching; expands discussion of isospin-breaking effect