Summary
Self‐splicing group II introns are present in the organelles of lower eukaryotes, plants and Bacteria and have been found recently in Archaea. It is generally accepted that group II introns ...originated in bacteria before spreading to mitochondria and chloroplasts. These introns are thought to be related to the progenitors of spliceosomal introns. Group II introns are also mobile genetic elements. In bacteria, they appear to spread using either other mobile genetic elements or low‐expression regions as target sites. Bacteria and Archaea genome sequence annotations have revealed the diversity of group II intron classes and that they are involved in vertical and horizontal inheritance.
Trends toward the widespread use of electric vehicles and renewable energy sources all point to continued growth in copper demand. This demand will be met mainly by new primary copper production, ...with recycling expected to contribute significantly to copper supply. Significant quantities of copper ore are presently mined from porphyry deposits in which typically, near-surface copper oxides are recovered hydrometallurgically by leaching, solvent extraction and electrowinning, whereas the deeper copper sulphides are only amenable to milling followed by pyrometallurgical processing and electrolytic refining. The Chilean copper porphyries together are the largest group of operating copper mines and are likely to remain so into the future. However, several of these deposits are forecast to show increasing levels of arsenic-bearing minerals, such as enargite. As mature copper mining districts exhaust the near-surface oxides and higher-grade sulphides, individual mines will need to adjust their operations accordingly. However, it is considered that due to such changes, re-engineering efforts might be more economically coordinated across several mines, to collectively handle the evolving ore feeds. The present paper adapts a discrete event simulation (DES) approach to support mine-to-smelter integration within porphyry copper districts. Sample computations are presented that are loosely based on the Chilean context.
Hirschsprung disease (HSCR; OMIM 142623) is a developmental disorder characterized by aganglionosis along variable lengths of the distal gastrointestinal tract, which results in intestinal ...obstruction. Interactions among known HSCR genes and/or unknown disease susceptibility loci lead to variable severity of phenotype. Neither linkage nor genome-wide association studies have efficiently contributed to completely dissect the genetic pathways underlying this complex genetic disorder. We have performed whole exome sequencing of 16 HSCR patients from 8 unrelated families with SOLID platform. Variants shared by affected relatives were validated by Sanger sequencing. We searched for genes recurrently mutated across families. Only variations in the FAT3 gene were significantly enriched in five families. Within-family analysis identified compound heterozygotes for AHNAK and several genes (N = 23) with heterozygous variants that co-segregated with the phenotype. Network and pathway analyses facilitated the discovery of polygenic inheritance involving FAT3, HSCR known genes and their gene partners. Altogether, our approach has facilitated the detection of more than one damaging variant in biologically plausible genes that could jointly contribute to the phenotype. Our data may contribute to the understanding of the complex interactions that occur during enteric nervous system development and the etiopathology of familial HSCR.
Investigation at a
φ
-factory can shed light on several debated issues in particle physics. We discuss: (i) recent theoretical development and experimental progress in kaon physics relevant for the ...Standard Model tests in the flavor sector, (ii) the sensitivity we can reach in probing CPT and Quantum Mechanics from time evolution of entangled-kaon states, (iii) the interest for improving on the present measurements of non-leptonic and radiative decays of kaons and
η
/
η
′ mesons, (iv) the contribution to understand the nature of light scalar mesons, and (v) the opportunity to search for narrow di-lepton resonances suggested by recent models proposing a hidden dark-matter sector. We also report on the
e
+
e
−
physics in the continuum with the measurements of (multi)hadronic cross sections and the study of
γ
γ
processes.
AbstractThis study presents the results of spaceborne monitoring of two posttensioned bridges in Virginia. Routine safety inspections revealed extensive cracking in the concrete girders. Problems ...were traced to the inadequate quality of tendon grouting, resulting in the partially bonded condition. The TerraSAR-X radar satellite, operated by the German Aerospace Center, was used to acquire radar imagery in the Staring SpotLight mode from the ascending and descending orbits at 11-day intervals. The data were processed with the SqueeSAR algorithm, resulting in millimeter-range precision of the time-displacement series. No permanent deformations were detected at the posttensioned segments during the monitoring period of 1.3 years. The high density of the measurement points allowed adequate characterization of bridge displacements. The results of the interferometric analysis attest to the feasibility of implementing satellite-based performance monitoring of bridges, offering an innovative asset management tool that can complement and augment current inspection methods.
The heavy photon search experiment (HPS) at the Thomas Jefferson National Accelerator Facility searches for electroproduced dark photons. We report results from the 2016 engineering run consisting of ...10 608 nb–1 of data for both the prompt and displaced vertex searches. A search for a prompt resonance in the e+e– invariant mass distribution between 39 and 179 MeV showed no evidence of dark photons above the large QED background, limiting the coupling of ε2≳10–5, in agreement with previous searches. The search for displaced vertices showed no evidence of excess signal over background in the masses between 60 and 150 MeV, but had insufficient luminosity to limit canonical heavy photon production. This is the first displaced vertex search result published by HPS. HPS has taken high-luminosity data runs in 2019 and 2021 that will explore new dark photon phase space.
Introduction In the foothills of the Cumberland Mountains, in central Appalachia (a region that spans 13 states in the US), sits an economically distressed and rural community of the United States. ...Once a thriving coal-mining area, this region now is reported as one of the hardest places to live in the US. Southeastern Kentucky, located in a remote, rocky, mountainous area surrounded by rivers and valleys and prone to flooding, experienced a major flood in Spring 2013 causing significant damage to homes and critical infrastructure. Purpose Aims of the study were to: (1) identify and better understand the contextual variables compounding the impact of a disaster event that occurred in Spring 2013; (2) identify ways participants managed antecedent circumstances, risk, and protective factors to cope with disaster up to 12 months post-event; and (3) further determine implications for community-focused interventions that may enhance recovery for vulnerable populations to promote greater outcomes of adaptation, wellness, and readiness.
Using an ethnographic mixed-methods approach, an inter-collaborative team conducted face-to-face interviews with (N=12) Appalachian residents about their disaster experience, documented observations and visual assessment of need on an observation tool, and used photography depicting structural and environmental conditions. A Health and Emergency Preparedness Assessment Survey Tool was used to collect demographic, health, housing, environment, and disaster readiness assessment data. Community stakeholders facilitated purposeful sampling through coordination of scheduled home visits.
Triangulation of all data sources provided evidence that the community had unique coping strategies related to faith and spirituality, cultural values and heritage, and social support to manage antecedent circumstances, risk, and protective factors during times of adversity that, in turn, enhanced resilience up to 12 months post-disaster. The community was found to have an innate capacity to persevere and utilize resources to manage and transcend adversity and restore equilibrium, which reflected components of resilience that deserve greater recognition and appreciation.
Resilience is a foundational concept for disaster science. A model of resilience for the rural Appalachia community was developed to visually depict the encompassing element of community-based interventions that may enhance coping strategies, mitigate risk factors, integrate protective factors, and strengthen access. Community-based interventions are recommended to strengthen resilience, yielding improved outcomes of adaptation, health and wellness, and disaster readiness. Banks LH , Davenport LA , Hayes MH , McArthur MA , Toro SN , King CE , Vazirani HM . Disaster impact on impoverished area of US: an inter-professional mixed method study. Prehosp Disaster Med. 2016;31(6):583-592.
The Heavy Photon Search test detector Battaglieri, M.; Boyarinov, S.; Bueltmann, S. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
03/2015, Letnik:
777, Številka:
C
Journal Article
Recenzirano
Odprti dostop
The Heavy Photon Search (HPS), an experiment to search for a hidden sector photon in fixed target electroproduction, is preparing for installation at the Thomas Jefferson National Accelerator ...Facility (JLab) in the Fall of 2014. As the first stage of this project, the HPS Test Run apparatus was constructed and operated in 2012 to demonstrate the experiment׳s technical feasibility and to confirm that the trigger rates and occupancies are as expected. This paper describes the HPS Test Run apparatus and readout electronics and its performance. In this setting, a heavy photon can be identified as a narrow peak in the e+e− invariant mass spectrum above the trident background or as a narrow invariant mass peak with a decay vertex displaced from the production target, so charged particle tracking and vertexing are needed for its detection. In the HPS Test Run, charged particles are measured with a compact forward silicon microstrip tracker inside a dipole magnet. Electromagnetic showers are detected in a PbW04 crystal calorimeter situated behind the magnet, and are used to trigger the experiment and identify electrons and positrons. Both detectors are placed close to the beam line and split top-bottom. This arrangement provides sensitivity to low-mass heavy photons, allows clear passage of the unscattered beam, and avoids the spray of degraded electrons coming from the target. The discrimination between prompt and displaced e+e− pairs requires the first layer of silicon sensors be placed only 10cm downstream of the target. The expected signal is small, and the trident background huge, so the experiment requires very large statistics. Accordingly, the HPS Test Run utilizes high-rate readout and data acquisition electronics and a fast trigger to exploit the essentially 100% duty cycle of the CEBAF accelerator at JLab.
Self‐splicing group II introns are thought to be the evolutionary progenitors of eukaryotic spliceosomal introns. The invasion of novel (ectopic) sites by group II introns is considered to be a key ...mechanism by which spliceosomal introns may have become widely dispersed. However, the dynamics of these events in populations are unknown. In bacteria, only two group II introns have been shown to splice and to be mobile in vivo. One of these introns, RmInt1 from Sinorhizobium meliloti, which encodes a protein with no endonuclease domain, has been shown to invade the ectopic oxi1 site independently of recombinase. In this study, we analysed ectopic transposition of the RmInt1 intron in a natural population of S. meliloti. We characterized S. meliloti isolates by polymerase chain reaction amplification of a gene, dapB, which is found only on the pRmeGR4b plasmid diagnostic of GR4‐type strains. The diversity within this specific field population of bacteria was analysed by restriction fragment length polymorphism using ISRm2011‐2 (homing site of RmInt1) and RmInt1 as probes. We found that ectopic transposition of RmInt1 to the oxi1 site occurred in this natural bacterial population. This ectopic transposition was also the most frequent genetic event observed. This work provides further evidence that the ectopic transposition of group II introns is an important mechanism for their spread in natural bacterial populations.
Feebly-interacting particles Carenza, Pierluca; Milstead, David A.; Wallisch, Benjamin
The European physical journal. C, Particles and fields,
12/2023, Letnik:
83, Številka:
12
Journal Article
Recenzirano
Odprti dostop
Particle physics today faces the challenge of explaining the mystery of dark matter, the origin of matter over anti-matter in the Universe, the origin of the neutrino masses, the apparent fine-tuning ...of the electro-weak scale, and many other aspects of fundamental physics. Perhaps the most striking frontier to emerge in the search for answers involves new physics at mass scales comparable to familiar matter, below the GeV-scale, or even radically below, down to sub-eV scales, and with very feeble interaction strength. New theoretical ideas to address dark matter and other fundamental questions predict such feebly interacting particles (FIPs) at these scales, and indeed, existing data provide numerous hints for such possibility. A vibrant experimental program to discover such physics is under way, guided by a systematic theoretical approach firmly grounded on the underlying principles of the Standard Model. This document represents the report of the FIPs 2022 workshop, held at CERN between the 17 and 21 October 2022 and aims to give an overview of these efforts, their motivations, and the decadal goals that animate the community involved in the search for FIPs.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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