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The Genotype-Tissue Expression (GTEx) project was established to characterize genetic effects on the transcriptome across human tissues and to link these regulatory mechanisms to trait and disease associations. Here, we present analyses of the version 8 data, examining 15,201 RNA-sequencing samples from 49 tissues of 838 postmortem donors. We comprehensively characterize genetic associations for gene expression and splicing in cis and trans, showing that regulatory associations are found for almost all genes, and describe the underlying molecular mechanisms and their contribution to allelic heterogeneity and pleiotropy of complex traits. Leveraging the large diversity of tissues, we provide insights into the tissue specificity of genetic effects and show that cell type composition is a key factor in understanding gene regulatory mechanisms in human tissues.

This Special Issue of the Astrophysical Journal Letters is dedicated to presenting initial results from the Great Observatories Origins Deep Survey (GOODS) that are primarily, but not exclusively, based on multi-band imaging data obtained with the Hubble Space Telescope (HST) and the Advanced Camera for Surveys (ACS). The survey covers roughly 320 square arcminutes in the ACS F435W, F606W, F814W, and F850LP bands, divided into two well-studied fields. Existing deep observations from the Chandra X-ray Observatory (CXO) and groundbased facilities are supplemented with new, deep imaging in the optical and

We report on the epitaxial growth of a group-IV ferromagnetic semiconductor, Mn(x)Ge(1-x), in which the Curie temperature is found to increase linearly with manganese (Mn) concentration from 25 to 116 kelvin. The p-type semiconducting character and hole-mediated exchange permit control of ferromagnetic order through application of a +/-0.5-volt gate voltage, a value compatible with present microelectronic technology. Total-energy calculations within density-functional theory show that the magnetically ordered phase arises from a long-range ferromagnetic interaction that dominates a short-range antiferromagnetic interaction. Calculated spin interactions and percolation theory predict transition temperatures larger than measured, consistent with the observed suppression of magnetically active Mn atoms and hole concentration.

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fossil fuels are being widely researched for the development of a sustainable energy system. Among the various candidates for green energy resources, hydrogen energy has been at the center of attention. [1,2] Hydrogen is both inexhaustible and environmentally friendly, because it can be produced from earth-abundant reactants such as water and methane and because no CO 2 or other toxic products are emitted during its conversion into other energy form such as electricity, respectively. Moreover, hydrogen can exhibit significantly larger energy density compared with other energy sources such as gasoline and coal. The most widely used method of hydrogen production today is steam reforming because of its low cost in the process. [3] Nevertheless, the release of carbon monoxide or carbon dioxide as byproducts in the steam reforming process diminishes the environmental merits of hydrogen energy. Thus, as a possible cleaner alternative, an electrolysis method that involves producing hydrogen by electrochemically splitting water has been extensively investigated. Using one of the most abundant resources, water, the production of hydrogen from it yields only oxygen as a byproduct.In the water electrolysis, the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) occur simultaneously, as described by the following equationsIn order for the reaction to proceed, a voltage of 1.23 V is theoretically required between an anode and a cathode. However, an overpotential (represented by the symbol η) should be additionally applied to account for the potential loss resulting from kinetic limitations occurring during the electrochemical reaction. The use of electrocatalysts can lower the overpotential by kinetically facilitating the water-splitting reaction either in HER or OER. Due to the nature of four-electron involving OER, it is generally believed that the OER is much more sluggish than the HER; thus, the development of efficient OER Hydrogen is a promising alternative fuel for efficient energy production and storage, with water splitting considered one of the most clean, environmentally friendly, and sustainable approaches to generate hydrogen. However, to meet industrial demands with electrolysis-generated hydrogen, the development of a low-cost and efficient catalyst for the oxygen evolution reaction (OER) is critical, while conventional catalysts are mostly based on precious metals. Many studies have thus focused on exploring new efficient nonprecious-metal catalytic systems and improving the understandings on the OER mechanism, resulting in the design of catalysts with superior activity compared with that of conventional catalysts. In particular, the use of multimetal rather than single-metal catalysts is demonstrated to yield remarkable performance improvement, as the metal composition in these catalysts can be tailored to modify the intrinsic properties affecting the OER. Herein, recent progress and accomplishments of multimetal catalytic systems, including several important groups of catalysts: layered h...

This paper presents a general approach for the probabilistic constraint evaluation in the reliability-based design optimization (RBDO). Different perspectives of the general approach are consistent in prescribing the probabilistic constraint, where the conventional reliability index approach (RIA) and the proposed performance measure approach (PMA) are identified as two special cases. PMA is shown to be inherently robust and more efficient in evaluating inactive probabilistic constraints, while RIA is more efficient for violated probabilistic constraints. Moreover, RBDO often yields a higher rate of convergence by using PMA, while RIA yields singularity in some cases.

Recent advances in the theory and experimental realization of ferromagnetic semiconductors give hope that a new generation of microelectronic devices based on the spin degree of freedom of the electron can be developed. This review focuses primarily on promising candidate materials ͑such as GaN, GaP and ZnO͒ in which there is already a technology base and a fairly good understanding of the basic electrical and optical properties. The introduction of Mn into these and other materials under the right conditions is found to produce ferromagnetism near or above room temperature.There are a number of other potential dopant ions that could be employed ͑such as Fe, Ni, Co, Cr͒ as suggested by theory ͓see, for example, Sato and Katayama-Yoshida, Jpn. J. Appl. Phys., Part 2 39, L555 ͑2000͔͒. Growth of these ferromagnetic materials by thin film techniques, such as molecular beam epitaxy or pulsed laser deposition, provides excellent control of the dopant concentration and the ability to grow single-phase layers. The mechanism for the observed magnetic behavior is complex and appears to depend on a number of factors, including Mn-Mn spacing, and carrier density and type. For example, in a simple Ruderman-Kittel-Kasuya-Yosida carrier-mediated exchange mechanism, the free-carrier/Mn ion interaction can be either ferromagnetic or antiferromagnetic depending on the separation of the Mn ions. Potential applications for ferromagnetic semiconductors and oxides include electrically controlled magnetic sensors and actuators, high-density ultralow-power memory and logic, spin-polarized light emitters for optical encoding, advanced optical switches and modulators and devices with integrated magnetic, electronic and optical functionality.