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Standing by Your Man Ray: Troubles with Antitrust Standing in Art Authentication Cases
In 1989, Joe Simon-Whelan, an intimate of Andy Warhol, purchased one of the artistβs silk-screened self portraits for 2,000,000 in exchange for the painting. However, members of the Andy Warhol Art Authentication Board, an entity created eight years after the Foundation, encouraged the buyer not to purchase the portrait until the Board had authenticated it. After Simon-Whelan eventually submitted the painting to the Board, the Board denied that Andy Warhol had authored the artwork. The Board invited Simon Whelan to resubmit his silk-screen with additional documentation; Simon-Whelan did, and the board denied the portraitβs authenticity a second time
Identification of Genes under Positive Selection Reveals Differences in Evolutionary Adaptation between Brown-Algal Species
Brown algae are an important taxonomic group in coastal ecosystems. The model brown algal species Ectocarpus siliculosus and Saccharina japonica are closely related lineages. Despite their close phylogenetic relationship, they vary greatly in morphology and physiology. To obtain further insights into the evolutionary forces driving divergence in brown algae, we analyzed 3,909 orthologs from both species to identify Genes Under Positive Selection (GUPS). About 12% of the orthologs in each species were considered to be under positive selection. Many GUPS are involved in membrane transport, regulation of homeostasis, and sexual reproduction in the small sporophyte of E. siliculosus, which is known to have a complex life cycle and to occupy a wide range of habitats. Genes involved in photosynthesis and cell division dominated the group of GUPS in the large kelp of S. japonica, which might explain why this alga has evolved the ability to grow very rapidly and to form some of the largest sporophytes. A significant number of molecular chaperones (e.g., heat-shock proteins) involved in stress responses were identified to be under positive selection in both species, potentially indicating their important roles for macroalgae to cope with the relatively variable environment of coastal ecosystems. Moreover, analysis of previously published microarray data of E. siliculosus showed that many GUPS in E. siliculosus were responsive to stress conditions, such as oxidative and hyposaline stress, whereas our RNA-seq data of S. japonica showed that GUPS in this species were most highly expressed in large sporophytes, which supports the suggestion that selection largely acts on different sets of genes in both marcoalgal species, potentially reflecting their adaptation to different ecological niches
Measurement of the cross-section and charge asymmetry of bosons produced in proton-proton collisions at TeV with the ATLAS detector
This paper presents measurements of the and cross-sections and the associated charge asymmetry as a
function of the absolute pseudorapidity of the decay muon. The data were
collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with
the ATLAS experiment at the LHC and correspond to a total integrated luminosity
of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements
varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the
1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured
with an uncertainty between 0.002 and 0.003. The results are compared with
predictions based on next-to-next-to-leading-order calculations with various
parton distribution functions and have the sensitivity to discriminate between
them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables,
submitted to EPJC. All figures including auxiliary figures are available at
https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13
Search for chargino-neutralino production with mass splittings near the electroweak scale in three-lepton final states in βs=13βTeV pp collisions with the ATLAS detector
A search for supersymmetry through the pair production of electroweakinos with mass splittings near the electroweak scale and decaying via on-shell W and Z bosons is presented for a three-lepton final state. The analyzed proton-proton collision data taken at a center-of-mass energy of βs=13ββTeV were collected between 2015 and 2018 by the ATLAS experiment at the Large Hadron Collider, corresponding to an integrated luminosity of 139ββfbβ1. A search, emulating the recursive jigsaw reconstruction technique with easily reproducible laboratory-frame variables, is performed. The two excesses observed in the 2015β2016 data recursive jigsaw analysis in the low-mass three-lepton phase space are reproduced. Results with the full data set are in agreement with the Standard Model expectations. They are interpreted to set exclusion limits at the 95% confidence level on simplified models of chargino-neutralino pair production for masses up to 345 GeV
Bioactive Endophytes Warrant Intensified Exploration and Conservation
A key argument in favor of conserving biodiversity is that as yet undiscovered biodiversity will yield products of great use to humans. However, the link between undiscovered biodiversity and useful products is largely conjectural. Here we provide direct evidence from bioassays of endophytes isolated from tropical plants and bioinformatic analyses that novel biology will indeed yield novel chemistry of potential value.We isolated and cultured 135 endophytic fungi and bacteria from plants collected in Peru. nrDNAs were compared to samples deposited in GenBank to ascertain the genetic novelty of cultured specimens. Ten endophytes were found to be as much as 15β30% different than any sequence in GenBank. Phylogenetic trees, using the most similar sequences in GenBank, were constructed for each endophyte to measure phylogenetic distance. Assays were also conducted on each cultured endophyte to record bioactivity, of which 65 were found to be bioactive.The novelty of our contribution is that we have combined bioinformatic analyses that document the diversity found in environmental samples with culturing and bioassays. These results highlight the hidden hyperdiversity of endophytic fungi and the urgent need to explore and conserve hidden microbial diversity. This study also showcases how undergraduate students can obtain data of great scientific significance
Hydrological controls on glacially exported microbial assemblages
The Greenland Ice Sheet (GrIS) exports approximately 400 km3 of freshwater annually to downstream freshwater and marine ecosystems. These meltwaters originate in a wide range of well-defined habitats that can be associated with very different physical environments within the ice sheet, ranging from oxygenated surface environments that are exposed to light and supplied with nutrients from atmospheric/aeolian sources to subglacial environments that are permanently dark, isolated from the atmosphere, and potentially anoxic. Hydrological conditions in the latter likely favor prolonged rock-water contact. The seasonally evolving hydrological system that drains meltwaters from the GrIS connects these distinct microbial habitats and exports the microbes contained within them to downstream ecosystems. The microbial assemblages exported in glacier meltwater may have an impact on downstream ecosystem function and development. We explored how the seasonal development of a glacial drainage system influences the character of microbial assemblages exported from the GrIS by monitoring the seasonal changes in hydrology, water chemistry, and microbial assemblage composition of meltwaters draining from a glacier in southwest Greenland. We found that the microbial assemblages exported in meltwaters varied in response to glacier hydrological flow path characteristics. Whether or not meltwaters passed through the subglacial environment was the first-order control on the composition of the microbial assemblages exported from the glacier, while water source (i.e., supraglacial or extraglacial) and subglacial residence times were second-order controls. Glacier hydrology therefore plays a fundamental role in determining the microbial exports from glaciated watersheds
Phenotypic Characterization of EIF2AK4 Mutation Carriers in a Large Cohort of Patients Diagnosed Clinically With Pulmonary Arterial Hypertension.
BACKGROUND: Pulmonary arterial hypertension (PAH) is a rare disease with an emerging genetic basis. Heterozygous mutations in the gene encoding the bone morphogenetic protein receptor type 2 (BMPR2) are the commonest genetic cause of PAH, whereas biallelic mutations in the eukaryotic translation initiation factor 2 alpha kinase 4 gene (EIF2AK4) are described in pulmonary veno-occlusive disease/pulmonary capillary hemangiomatosis. Here, we determine the frequency of these mutations and define the genotype-phenotype characteristics in a large cohort of patients diagnosed clinically with PAH. METHODS: Whole-genome sequencing was performed on DNA from patients with idiopathic and heritable PAH and with pulmonary veno-occlusive disease/pulmonary capillary hemangiomatosis recruited to the National Institute of Health Research BioResource-Rare Diseases study. Heterozygous variants in BMPR2 and biallelic EIF2AK4 variants with a minor allele frequency of <1:10β000 in control data sets and predicted to be deleterious (by combined annotation-dependent depletion, PolyPhen-2, and sorting intolerant from tolerant predictions) were identified as potentially causal. Phenotype data from the time of diagnosis were also captured. RESULTS: Eight hundred sixty-four patients with idiopathic or heritable PAH and 16 with pulmonary veno-occlusive disease/pulmonary capillary hemangiomatosis were recruited. Mutations in BMPR2 were identified in 130 patients (14.8%). Biallelic mutations in EIF2AK4 were identified in 5 patients with a clinical diagnosis of pulmonary veno-occlusive disease/pulmonary capillary hemangiomatosis. Furthermore, 9 patients with a clinical diagnosis of PAH carried biallelic EIF2AK4 mutations. These patients had a reduced transfer coefficient for carbon monoxide (Kco; 33% [interquartile range, 30%-35%] predicted) and younger age at diagnosis (29 years; interquartile range, 23-38 years) and more interlobular septal thickening and mediastinal lymphadenopathy on computed tomography of the chest compared with patients with PAH without EIF2AK4 mutations. However, radiological assessment alone could not accurately identify biallelic EIF2AK4 mutation carriers. Patients with PAH with biallelic EIF2AK4 mutations had a shorter survival. CONCLUSIONS: Biallelic EIF2AK4 mutations are found in patients classified clinically as having idiopathic and heritable PAH. These patients cannot be identified reliably by computed tomography, but a low Kco and a young age at diagnosis suggests the underlying molecular diagnosis. Genetic testing can identify these misclassified patients, allowing appropriate management and early referral for lung transplantation
Human Cytomegalovirus IE1 Protein Elicits a Type II Interferon-Like Host Cell Response That Depends on Activated STAT1 but Not Interferon-Ξ³
Human cytomegalovirus (hCMV) is a highly prevalent pathogen that, upon primary
infection, establishes life-long persistence in all infected individuals. Acute
hCMV infections cause a variety of diseases in humans with developmental or
acquired immune deficits. In addition, persistent hCMV infection may contribute
to various chronic disease conditions even in immunologically normal people. The
pathogenesis of hCMV disease has been frequently linked to inflammatory host
immune responses triggered by virus-infected cells. Moreover, hCMV infection
activates numerous host genes many of which encode pro-inflammatory proteins.
However, little is known about the relative contributions of individual viral
gene products to these changes in cellular transcription. We systematically
analyzed the effects of the hCMV 72-kDa immediate-early 1 (IE1) protein, a major
transcriptional activator and antagonist of type I interferon (IFN) signaling,
on the human transcriptome. Following expression under conditions closely
mimicking the situation during productive infection, IE1 elicits a global type
II IFN-like host cell response. This response is dominated by the selective
up-regulation of immune stimulatory genes normally controlled by IFN-Ξ³ and
includes the synthesis and secretion of pro-inflammatory chemokines.
IE1-mediated induction of IFN-stimulated genes strictly depends on
tyrosine-phosphorylated signal transducer and activator of transcription 1
(STAT1) and correlates with the nuclear accumulation and sequence-specific
binding of STAT1 to IFN-Ξ³-responsive promoters. However, neither synthesis
nor secretion of IFN-Ξ³ or other IFNs seems to be required for the
IE1-dependent effects on cellular gene expression. Our results demonstrate that
a single hCMV protein can trigger a pro-inflammatory host transcriptional
response via an unexpected STAT1-dependent but IFN-independent mechanism and
identify IE1 as a candidate determinant of hCMV pathogenicity
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