1,109 research outputs found
Soliton pair dynamics in patterned ferromagnetic ellipses
Confinement alters the energy landscape of nanoscale magnets, leading to the
appearance of unusual magnetic states, such as vortices, for example. Many
basic questions concerning dynamical and interaction effects remain unanswered,
and nanomagnets are convenient model systems for studying these fundamental
physical phenomena. A single vortex in restricted geometry, also known as a
non-localized soliton, possesses a characteristic translational excitation mode
that corresponds to spiral-like motion of the vortex core around its
equilibrium position. Here, we investigate, by a microwave reflection
technique, the dynamics of magnetic soliton pairs confined in lithographically
defined, ferromagnetic Permalloy ellipses. Through a comparison with
micromagnetic simulations, the observed strong resonances in the subgigahertz
frequency range can be assigned to the translational modes of vortex pairs with
parallel or antiparallel core polarizations. Vortex polarizations play a
negligible role in the static interaction between two vortices, but their
effect dominates the dynamics.Comment: supplemental movies on
http://www.nature.com/nphys/journal/v1/n3/suppinfo/nphys173_S1.htm
Electronic stress tensor analysis of hydrogenated palladium clusters
We study the chemical bonds of small palladium clusters Pd_n (n=2-9)
saturated by hydrogen atoms using electronic stress tensor. Our calculation
includes bond orders which are recently proposed based on the stress tensor. It
is shown that our bond orders can classify the different types of chemical
bonds in those clusters. In particular, we discuss Pd-H bonds associated with
the H atoms with high coordination numbers and the difference of H-H bonds in
the different Pd clusters from viewpoint of the electronic stress tensor. The
notion of "pseudo-spindle structure" is proposed as the region between two
atoms where the largest eigenvalue of the electronic stress tensor is negative
and corresponding eigenvectors forming a pattern which connects them.Comment: 22 pages, 13 figures, published online, Theoretical Chemistry
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Search for intermediate mass black hole binaries in the first and second observing runs of the Advanced LIGO and Virgo network
Gravitational-wave astronomy has been firmly established with the detection of gravitational waves from the merger of ten stellar-mass binary black holes and a neutron star binary. This paper reports on the all-sky search for gravitational waves from intermediate mass black hole binaries in the first and second observing runs of the Advanced LIGO and Virgo network. The search uses three independent algorithms: two based on matched filtering of the data with waveform templates of gravitational-wave signals from compact binaries, and a third, model-independent algorithm that employs no signal model for the incoming signal. No intermediate mass black hole binary event is detected in this search. Consequently, we place upper limits on the merger rate density for a family of intermediate mass black hole binaries. In particular, we choose sources with total masses M=m1+m2ϵ[120,800] M and mass ratios q=m2/m1ϵ[0.1,1.0]. For the first time, this calculation is done using numerical relativity waveforms (which include higher modes) as models of the real emitted signal. We place a most stringent upper limit of 0.20 Gpc-3 yr-1 (in comoving units at the 90% confidence level) for equal-mass binaries with individual masses m1,2=100 M and dimensionless spins χ1,2=0.8 aligned with the orbital angular momentum of the binary. This improves by a factor of ∼5 that reported after Advanced LIGO's first observing run
Glycogen Synthase Kinase (GSK) 3β phosphorylates and protects nuclear myosin 1c from proteasome-mediated degradation to activate rDNA transcription in early G1 cells
Nuclear myosin 1c (NM1) mediates RNA polymerase I (pol I) transcription activation and cell cycle progression by facilitating PCAF-mediated H3K9 acetylation, but the molecular mechanism by which NM1 is regulated remains unclear. Here, we report that at early G1 the glycogen synthase kinase (GSK) 3β phosphorylates and stabilizes NM1, allowing for NM1 association with the chromatin. Genomic analysis by ChIP-Seq showed that this mechanism occurs on the rDNA as active GSK3β selectively occupies the gene. ChIP assays and transmission electron microscopy in GSK3β-/- mouse embryonic fibroblasts indicated that at G1 rRNA synthesis is suppressed due to decreased H3K9 acetylation leading to a chromatin state incompatible with transcription. We found that GSK3β directly phosphorylates the endogenous NM1 on a single serine residue (Ser-1020) located within the NM1 C-terminus. In G1 this phosphorylation event stabilizes NM1 and prevents NM1 polyubiquitination by the E3 ligase UBR5 and proteasome-mediated degradation. We conclude that GSK3β-mediated phosphorylation of NM1 is required for pol I transcription activation
Candida glabrata : a review of its features and resistance
Candida species belong to the normal microbiota of the oral cavity and gastrointestinal and vaginal tracts, and are responsible for several clinical manifestations, from mucocutaneous overgrowth to bloodstream infections. Once believed to be non-pathogenic, Candida glabrata was rapidly blamable for many human diseases. Year after year, these pathological circumstances are more recurrent and problematic to treat, especially when patients reveal any level of immunosuppression. These difficulties arise from the capacity of C. glabrata to form biofilms and also from its high resistance to traditional antifungal therapies. Thus, this review intends to present an excerpt of the biology, epidemiology, and pathology of C. glabrata, and detail an approach to its resistance mechanisms based on studies carried out up to the present.The authors are grateful to strategic project PTDC/SAU-MIC/119069/2010 for the financial support to the research center and for Celia F. Rodrigues' grant
Meta-analysis of GWAS of over 16,000 individuals with autism spectrum disorder highlights a novel locus at 10q24.32 and a significant overlap with schizophrenia.
To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked FilesOver the past decade genome-wide association studies (GWAS) have been applied to aid in the understanding of the biology of traits. The success of this approach is governed by the underlying effect sizes carried by the true risk variants and the corresponding statistical power to observe such effects given the study design and sample size under investigation. Previous ASD GWAS have identified genome-wide significant (GWS) risk loci; however, these studies were of only of low statistical power to identify GWS loci at the lower effect sizes (odds ratio (OR) <1.15).We conducted a large-scale coordinated international collaboration to combine independent genotyping data to improve the statistical power and aid in robust discovery of GWS loci. This study uses genome-wide genotyping data from a discovery sample (7387 ASD cases and 8567 controls) followed by meta-analysis of summary statistics from two replication sets (7783 ASD cases and 11359 controls; and 1369 ASD cases and 137308 controls).We observe a GWS locus at 10q24.32 that overlaps several genes including PITX3, which encodes a transcription factor identified as playing a role in neuronal differentiation and CUEDC2 previously reported to be associated with social skills in an independent population cohort. We also observe overlap with regions previously implicated in schizophrenia which was further supported by a strong genetic correlation between these disorders (Rg = 0.23; P = 9 × 10(-6)). We further combined these Psychiatric Genomics Consortium (PGC) ASD GWAS data with the recent PGC schizophrenia GWAS to identify additional regions which may be important in a common neurodevelopmental phenotype and identified 12 novel GWS loci. These include loci previously implicated in ASD such as FOXP1 at 3p13, ATP2B2 at 3p25.3, and a 'neurodevelopmental hub' on chromosome 8p11.23.This study is an important step in the ongoing endeavour to identify the loci which underpin the common variant signal in ASD. In addition to novel GWS loci, we have identified a significant genetic correlation with schizophrenia and association of ASD with several neurodevelopmental-related genes such as EXT1, ASTN2, MACROD2, and HDAC4.National Institutes of Mental Health (NIMH, USA)
ACE Network
Autism Genetic Resource Exchange (AGRE) is a program of Autism Speaks (USA)
The Autism Genome Project (AGP) from Autism Speaks (USA)
Canadian Institutes of Health Research (CIHR), Genome Canada
Health Research Board (Ireland)
Hilibrand Foundation (USA)
Medical Research Council (UK)
National Institutes of Health (USA)
Ontario Genomics Institute
University of Toronto McLaughlin Centre
Simons Foundation
Johns Hopkins
Autism Consortium of Boston
NLM Family foundation
National Institute of Health grants
National Health Medical Research Council
Scottish Rite
Spunk Fund, Inc.
Rebecca and Solomon Baker Fund
APEX Foundation
National Alliance for Research in Schizophrenia and Affective Disorders (NARSAD)
endowment fund of the Nancy Pritzker Laboratory (Stanford)
Autism Society of America
Janet M. Grace Pervasive Developmental Disorders Fund
The Lundbeck Foundation
universities and university hospitals of Aarhus and Copenhagen
Stanley Foundation
Centers for Disease Control and Prevention (CDC)
Netherlands Scientific Organization
Dutch Brain Foundation
VU University Amsterdam
Trinity Centre for High Performance Computing through Science Foundation Ireland
Autism Genome Project (AGP) from Autism Speak
The disruption of proteostasis in neurodegenerative diseases
Cells count on surveillance systems to monitor and protect the cellular proteome which, besides being highly heterogeneous, is constantly being challenged by intrinsic and environmental factors. In this context, the proteostasis network (PN) is essential to achieve a stable and functional proteome. Disruption of the PN is associated with aging and can lead to and/or potentiate the occurrence of many neurodegenerative diseases (ND). This not only emphasizes the importance of the PN in health span and aging but also how its modulation can be a potential target for intervention and treatment of human diseases.info:eu-repo/semantics/publishedVersio
A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)
Meeting abstrac
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