Metal sources of world-class polymetallic W–Sn Skarns in the Nanling Range, South China: Granites versus sedimentary rocks?

Widespread, large-scale polymetallic W–Sn mineralization occurs throughout the Nanling Range (South China) dated 160–150Ma, and related to widely developed coeval granitic magmatism. Although intense research has been carried out on these deposits, the relative contribution of ore-forming elements either from granites or from surrounding strata is still debated. In addition, the factors controlling the primary metallogenic element in any given skarn deposit (e.g., W-dominated or Sn-dominated) are still unclear. Here, we select three of the most significant skarn-deposits (i.e., Huangshaping W–Mo–Sn, Shizhuyuan W–Sn–Mo–Bi and Xianghualing Sn), and compare their whole-rock geochemistry with the composition of associated granites and strata. The contents of Si, Al and most trace elements in skarns are controlled by the parent granite, whereas their Fe, Ca, Mg, Mn, Ti, Sr and REE patterns are strongly influenced by the wall rock. Samples from the Huangshaping skarn vary substantially in elemental composition, probably indicating their varied protoliths. Strata at the Shizhuyuan deposit exerted a strong control during metasomatism, whereas this occurred to a lesser degree at Huangshaping and Xianghualing. This correlates with increasing magma differentiation and increasing reduction state of granitic magmas, which along with the degree of stratigraphic fluid circulation, exert the primary control on dominant metallogenic species. We propose that wall rock sediments played an important role in the formation of W–Sn polymetallic mineralization in South China

The Deep Space Network: A Radio Communications Instrument for Deep Space Exploration

The primary purpose of the Deep Space Network (DSN) is to serve as a communications instrument for deep space exploration, providing communications between the spacecraft and the ground facilities. The uplink communications channel provides instructions or commands to the spacecraft. The downlink communications channel provides command verification and spacecraft engineering and science instrument payload data

Draft Genome Sequence of the Enteropathogenic Bacterium Campylobacter jejuni Strain cj255.

Published onlineJournal ArticleThe enteropathogen Campylobacter jejuni is a global health disaster, being one of the leading causes of bacterial gastroenteritis. Here, we present the draft genome sequence of C. jejuni strain cj255, isolated from a chicken source in Islamabad, Pakistan. The draft genome sequence will aid in epidemiological studies and quarantine of this broad-host-range pathogen.Higher Education Commission of Pakistan and British Counci

Differentiating between inherited and autocrystic zircon in granitoids

The Maniitsoq map project is supported by the Ministry of Mineral Resources, Government of Greenland. The LA-ICP-MS instruments in the JdLC were funded via an Australian Geophysical Observing System grant provided to AuScope Pty Ltd. by the AQ44 Australian Education Investment Fund program.Inherited zircon, crystals that did not form in situ from their host magma but were incorporated from either the source region or assimilated from the wall-rock, is common but can be difficult to identify. Age, chemical and/or textural dissimilarity to the youngest zircon fraction are the primary mechanisms of distinguishing such grains. However, in Zr-undersaturated magmas, the entire zircon population may be inherited and, if not identifiable via textural constraints, can lead to erroneous interpretation of magmatic crystallization age and magma source. Here, we present detailed field mapping of cross-cutting relationships, whole-rock geochemistry and zircon textural, U-Pb and trace element data of trondhjemite, granodiorite and granite from two localities in a complex Archean gneiss terrane in southwest Greenland, which reveal cryptic zircon inheritance. Zircon textural, U–Pb and trace element data demonstrate that, in both localities, trondhjemite is the oldest rock (3011 ± 5 Ma, 2σ), which is intruded by granodiorite (2978 ± 4 Ma, 2σ). However, granite intrusions, constrained by cross-cutting relationships as the youngest component, only contain inherited zircon derived from trondhjemite and granodiorite based on ages and trace element concentrations. Without age constraints on the older two lithologies, it would be tempting to consider the youngest zircon fraction as recording crystallization of the granite but this would be erroneous. Furthermore, whole-rock geochemistry indicates that the granite contains only 6 µg g-1 Zr, extremely low for a granitoid with ∼77 wt. % SiO2. Such low Zr concentration explains the lack of autocrystic zircon in the granite. We expand on a differentiation tool that uses Th/U ratios in zircon versus that in the whole rock to aid in the identification of inherited zircon. This work emphasizes the need for field observations, geochemistry, grain characterization, and precise geochronology to accurately determine igneous crystallization ages and differentiate between inherited and autocrystic zircon.PostprintPeer reviewe

Regional zircon U-Pb geochronology for the Maniitsoq region, southwest Greenland

The Ministry of Mineral Resources, Government of Greenland, funded this project. Analyses in the JdLC GeoHistory Facility were enabled by instrumentation supported by AuScope (auscope.org.au) and the Australian Government via the National Collaborative Research Infrastructure Strategy. The Tescan Mira3 FEG-SEM was funded through the Australian Research Council LIEF program.Zircon U-Pb geochronology places high-temperature geological events into temporal context. Here, we present a comprehensive zircon U-Pb geochronology dataset for the Meso- to Neoarchean Maniitsoq region in southwest Greenland, which includes the Akia Terrane, Tuno Terrane, and the intervening Alanngua Complex. The magmatic and metamorphic processes recorded in these terranes straddle a key change-point in early Earth geodynamics. This dataset comprises zircon U-Pb ages for 121 samples, including 46 that are newly dated. A principal crystallization peak occurs across all three terranes at ca. 3000 Ma, with subordinate crystallization age peaks at 3200 Ma (Akia Terrane and Alanngua Complex only), 2720 Ma and 2540 Ma. Metamorphic age peaks occur at 2990 Ma, 2820-2700 Ma, 2670-2600 Ma and 2540 Ma. Except for one sample, all dated metamorphic zircon growth after the Neoarchean occurred in the Alanngua Complex or within 20 km of its boundaries. This U-Pb dataset provides an important resource for addressing Earth Science topics as diverse as crustal evolution, fluid-rock interaction and mineral deposit genesis.Publisher PDFPeer reviewe

Early visual foraging in relationship to familial risk for autism and hyperactivity/inattention

Objective. Information foraging is atypical in both autism spectrum disorders (ASDs) and ADHD; however, while ASD is associated with restricted exploration and preference for sameness, ADHD is characterized by hyperactivity and increased novelty seeking. Here, we ask whether similar biases are present in visual foraging in younger siblings of children with a diagnosis of ASD with or without additional high levels of hyperactivity and inattention. Method. Fifty-four low-risk controls (LR) and 50 high-risk siblings (HR) took part in an eye-tracking study at 8 and 14 months and at 3 years of age. Results. At 8 months, siblings of children with ASD and low levels of hyperactivity/inattention (HR/ASD-HI) were more likely to return to previously visited areas in the visual scene than were LR and siblings of children with ASD and high levels of hyperactivity/inattention (HR/ASD+HI). Conclusion. We show that visual foraging is atypical in infants at-risk for ASD. We also reveal a paradoxical effect, in that additional family risk for ADHD core symptoms mitigates the effect of ASD risk on visual information foraging

Minimizing Penile Prosthesis Implant Infection: What Can We Learn From Orthopedic Surgery?

The implantation of penile protheses for the surgical treatment of erectile dysfunction has risen in popularity over the past several decades. Considerable advances have been made in surgical protocol and device design, specifically targeting infection prevention. Despite these efforts, device infection remains a critical problem, which causes significant physical and emotional burden to the patient. The aim of this review is to broaden the discussion of best practices by not only examining practices in urology, but additionally delving into the field of orthopedic surgery to identify techniques and approaches that may be applied to penile prothesis surgery

A practical approach to achieving agility : a theory of constraints perspective

This article documents an action research (AR) project aimed at identifying the practical steps needed to become an agile manufacturer through a combination of the theory of constraints (TOC) and resource- based view (RBV) approaches in a small to medium enterprise (SME) in the Australian manufacturing sector. To date, lean production has been highlighted as a possible catalyst for creating an agile manufacturer, despite the evidence suggesting that lean manufacturing lacks the responsiveness and adaptability to effectively handle a rapidly changing market place and only works well in a stable environment. A more flexible system of production is required to fully encompass the agile characteristics needed to attain a competitive advantage. This research provides empirical evidence that the TOC perspective can be used as a practical approach for becoming an agile manufacturer. The study provides a workable approach for small firms to achieve ‘Agility’ in practice

Managing better: Children, parents, and asthma

To evaluate a health education program to improve family management of asthma, 310 children with asthma and their 290 parents were randomly assigned to a program or control group. Program families participated in health education designed to resolve specific management problems and build self-confidence in the ability to manage asthma. Following education, program parents scored better on an asthma self-management index than parents in the control group (+1.57 versus -0.83, P P P P P P < 0.05). Program children reported significantly less worry than control children about the limitations asthma imposes and about making mistakes at school.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26238/1/0000318.pd