1,982 research outputs found
On the Molecular and Submolecular Structure of the Semiquinone Cations of Alloxazines and Isoalloxazines as Revealed by Electron-Paramagnetic-Resonance Spectroscopy
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66144/1/j.1432-1033.1981.tb05295.x.pd
Techno-Economic Assessment & Life-Cycle Assessment Guidelines for CO2 Utilization
NOTE: Updated version 1.1 available at http://hdl.handle.net/2027.42/162573
Climate change is one of the largest challenges of our time. One of the major causes of anthropogenic climate change, carbon dioxide, also leads to ocean acidification. Left unaddressed, these two challenges will alter ecosystems and fundamentally change life, as we know it. Under the auspices of the UN Framework Convention on Climate Change and through the Paris Agreement, there is a commitment to keep global temperature increase to well below two degrees Celsius. This will require a variety of strategies including increased renewable power generation and broad scale electrification, increased energy efficiency, and carbon-negative technologies.
We believe that Life Cycle Assessment (LCA) is necessary to prove that a technology could contribute to the mitigation of environmental impacts and that Techno-Economic Assessment (TEA) will show how the technology could be competitively delivered in the market. Together the guidelines for LCA and TEA that are presented in this document are a valuable toolkit for promoting carbon capture and utilization (CCU) technology development.Development of standardized CO2 Life Cycle and Techno-economic Assessment Guidelines was commissioned by CO2 Sciences, Inc., with the support of 3M, EIT Climate-KIC, CO2 Value Europe, Emissions Reduction Alberta, Grantham Foundation for the Protection of the Environment, R. K. Mellon Foundation, Cynthia and George Mitchell Foundation, National Institute of Clean and Low Carbon Energy, Praxair, Inc., XPRIZE and generous individuals who are committed to action to address climate change.https://deepblue.lib.umich.edu/bitstream/2027.42/145436/3/Global_CO2_Initiative_TEA_LCA_Guidelines-2018.pdf-
Endstation for ultrafast magnetic scattering experiments at the free-electron laser in Hamburg
This content may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This material originally appeared in Review of Scientific Instruments 84, 013906 (2013) and may be found at https://doi.org/10.1063/1.4773543.An endstation for pumpâprobe small-angle X-ray scattering (SAXS) experiments at the free-electron laser in Hamburg (FLASH) is presented. The endstation houses a solid-state absorber, optical incoupling for pumpâprobe experiments, time zero measurement, sample chamber, and detection unit. It can be used at all FLASH beamlines in the whole photon energy range offered by FLASH. The capabilities of the setup are demonstrated by showing the results of resonant magnetic SAXS measurements on cobalt-platinum multilayer samples grown on freestanding Si3N4 membranes and pump-laser-induced grid structures in multilayer samples.BMBF, 05K10GU4, Verbundprojekt: FSP 301 - FLASH: Nanoskopische Systeme. Teilprojekt 6: Aufbau einer Plattform fĂŒr Experimente mit ultimativer Orts- und Zeitauflösung unter Ausnutzung der kohĂ€renten Beugung weicher Röntgenstrahlung an PETRA III und FLASHDFG, 13002249, SFB 668: Magnetismus vom Einzelatom zur NanostrukturDFG, 170620586, SFB 925: Licht-induzierte Dynamik und Kontrolle korrelierter Quantensystem
Indirect excitation of ultrafast demagnetization
Does the excitation of ultrafast magnetization require direct interaction between the photons of the optical pump pulse and the magnetic layer? Here, we demonstrate unambiguously that this is not the case. For this we have studied the magnetization dynamics of a ferromagnetic cobalt/palladium multilayer capped by an IR-opaque aluminum layer. Upon excitation with an intense femtosecond-short IR laser pulse, the film exhibits the classical ultrafast demagnetization phenomenon although only a negligible number of IR photons penetrate the aluminum layer. In comparison with an uncapped cobalt/palladium reference film, the initial demagnetization of the capped film occurs with a delayed onset and at a slower rate. Both observations are qualitatively in line with energy transport from the aluminum layer into the underlying magnetic film by the excited, hot electrons of the aluminum film. Our data thus confirm recent theoretical predictions
An ensemble of structures of Burkholderia pseudomallei 2,3-bisphosphoglycerate-dependent phosphoglycerate mutase
An ensemble of crystal structures are reported for 2,3-bisphosphoglycerate-dependent phosphoglycerate mutase from B. pseudomallei. The structures include two vanadate complexes, revealing the structure of a close analogue of the transition state for phosphate transfer
PEtab -- interoperable specification of parameter estimation problems in systems biology
Reproducibility and reusability of the results of data-based modeling studies
are essential. Yet, there has been -- so far -- no broadly supported format for
the specification of parameter estimation problems in systems biology. Here, we
introduce PEtab, a format which facilitates the specification of parameter
estimation problems using Systems Biology Markup Language (SBML) models and a
set of tab-separated value files describing the observation model and
experimental data as well as parameters to be estimated. We already implemented
PEtab support into eight well-established model simulation and parameter
estimation toolboxes with hundreds of users in total. We provide a Python
library for validation and modification of a PEtab problem and currently 20
example parameter estimation problems based on recent studies. Specifications
of PEtab, the PEtab Python library, as well as links to examples, and all
supporting software tools are available at https://github.com/PEtab-dev/PEtab,
a snapshot is available at https://doi.org/10.5281/zenodo.3732958. All original
content is available under permissive licenses
Common Genetic Variants Contribute to Risk of Transposition of the Great Arteries
RATIONALE: Dextro-transposition of the great arteries (D-TGA) is a severe congenital heart defect which affects approximately 1 in 4,000 live births. While there are several reports of D-TGA patients with rare variants in individual genes, the majority of D-TGA cases remain genetically elusive. Familial recurrence patterns and the observation that most cases with D-TGA are sporadic suggest a polygenic inheritance for the disorder, yet this remains unexplored. OBJECTIVE: We sought to study the role of common single nucleotide polymorphisms (SNPs) in risk for D-TGA. METHODS AND RESULTS: We conducted a genome-wide association study in an international set of 1,237 patients with D-TGA and identified a genome-wide significant susceptibility locus on chromosome 3p14.3, which was subsequently replicated in an independent case-control set (rs56219800, meta-analysis P=8.6x10-10, OR=0.69 per C allele). SNP-based heritability analysis showed that 25% of variance in susceptibility to D-TGA may be explained by common variants. A genome-wide polygenic risk score derived from the discovery set was significantly associated to D-TGA in the replication set (P=4x10-5). The genome-wide significant locus (3p14.3) co-localizes with a putative regulatory element that interacts with the promoter of WNT5A, which encodes the Wnt Family Member 5A protein known for its role in cardiac development in mice. We show that this element drives reporter gene activity in the developing heart of mice and zebrafish and is bound by the developmental transcription factor TBX20. We further demonstrate that TBX20 attenuates Wnt5a expression levels in the developing mouse heart. CONCLUSIONS: This work provides support for a polygenic architecture in D-TGA and identifies a susceptibility locus on chromosome 3p14.3 near WNT5A. Genomic and functional data support a causal role of WNT5A at the locus
Mendelian randomization integrating GWAS and eQTL data reveals genetic determinants of complex and clinical traits
Genome-wide association studies (GWAS) have identified thousands of variants associated with complex traits, but their biological interpretation often remains unclear. Most of these variants overlap with expression QTLs, indicating their potential involvement in regulation of gene expression. Here, we propose a transcriptome-wide summary statistics-based Mendelian Randomization approach (TWMR) that uses multiple SNPs as instruments and multiple gene expression traits as exposures, simultaneously. Applied to 43 human phenotypes, it uncovers 3,913 putatively causal gene-trait associations, 36% of which have no genome-wide significant SNP nearby in previous GWAS. Using independent association summary statistics, we find that the majority of these loci were missed by GWAS due to power issues. Noteworthy among these links is educational attainment-associated BSCL2, known to carry mutations leading to a Mendelian form of encephalopathy. We also find pleiotropic causal effects suggestive of mechanistic connections. TWMR better accounts for pleiotropy and has the potential to identify biological mechanisms underlying complex traits
Refining Attention-Deficit/Hyperactivity Disorder and Autism Spectrum Disorder Genetic Loci by Integrating Summary Data From Genome-wide Association, Gene Expression, and DNA Methylation Studies
Background: Recent genome-wide association studies (GWASs) identified the first genetic loci associated with attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). The next step is to use these results to increase our understanding of the biological mechanisms involved. Most of the identified variants likely influence gene regulation. The aim of the current study is to shed light on the mechanisms underlying the genetic signals and prioritize genes by integrating GWAS results with gene expression and DNA methylation (DNAm) levels. Methods: We applied summary-dataâbased Mendelian randomization to integrate ADHD and ASD GWAS data with fetal brain expression and methylation quantitative trait loci, given the early onset of these disorders. We also analyzed expression and methylation quantitative trait loci datasets of adult brain and blood, as these provide increased statistical power. We subsequently used summary-dataâbased Mendelian randomization to investigate if the same variant influences both DNAm and gene expression levels. Results: We identified multiple gene expression and DNAm levels in fetal brain at chromosomes 1 and 17 that were associated with ADHD and ASD, respectively, through pleiotropy at shared genetic variants. The analyses in brain and blood showed additional associated gene expression and DNAm levels at the same and additional loci, likely because of increased statistical power. Several of the associated genes have not been identified in ADHD and ASD GWASs before. Conclusions: Our findings identified the genetic variants associated with ADHD and ASD that likely act through gene regulation. This facilitates prioritization of candidate genes for functional follow-up studies
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