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.
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.
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.
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.
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.
Here, we summarize the ongoing scientific program of the 12 GeV Continuous Electron Beam Accelerator Facility (CEBAF) and give an outlook into future opportunities. The program addresses important ...topics in nuclear, hadronic, and electroweak physics, including nuclear femtography, meson and baryon spectroscopy, quarks and gluons in nuclei, precision tests of the standard model and dark sector searches. Potential upgrades of CEBAF and their impact on scientific reach are discussed, such as higher luminosity, the addition of polarized and unpolarized positron beams, and doubling the beam energy.
Summary
An interesting alternative to landfills for disposing of organic residues is their addition to soil as composted organic residues. There is little information available about the long‐term ...benefits following prolonged periods of application. After 12 years of annual incorporation of organic amendments to the soil of a vineyard, three soil characteristics were analysed: mineral content, bacterial community and soil greenhouse gas (GHG) emissions. The organic amendments were (i) a pelletized organic compost (PEL) made from plant, animal and sewage sludge residues, (ii) a compost made from the organic fraction of municipal solid waste (OF‐MSW) and (iii) a stabilized sheep manure compost (SMC). Mineral fertilizer (NPK) and an unaltered control treatment were also included. Our results showed that long‐term application of treated residues as compost changed soil nutrient content, bacterial community and gas emission rates. For instance, SMC increased nutrients and soil organic matter (OM) throughout the experiment. There was a change in bacterial community structure, with an increase in the phylum Proteobacteria observed for all four treated soils, and an increase in the phylum Bacteroidetes for PEL, OF‐MSW and SMC treatments. Among the organically‐amended soils, the amount of Adhaeribacter increased by a factor of 2.5 times more than the control, which reported a total of 2.0% of the bacterial community compared with 5.6% for PEL, 5.2% for OF‐MSW and 5.0% for SMC. Adhaeribacter may be a genus that specializes in the degradation of residues in the different composts. The SMC treatment had the largest Chao1 estimator and was the most biodiverse of all treatments. These changes in bacterial community structure did not correlate with the observed GHG fluxes from the sampling day. The application of amendments did not affect N2O fluxes. However, the application of treatments slightly reduced the capacity for CH4 sequestration by soil with respect to the untreated soils. Compost is an effective method to increase soil fertility. Soil GHG emissions should be further evaluated.
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