751 research outputs found
Stimulating exploration by government-sponsored regional geoscience surveys
The island of Ireland is one of the most attractive places for mineral exploration and development, according to a recent global review. The Republic of Ireland is a major European producer of lead-zinc and historically of copper, lead-silver and alluvial gold. Northern Ireland has one gold mine in production, a second gold prospect at an advanced stage of exploration, and one salt mine. In the past lead, iron and coal mining have all been prominent. Other minerals that are or have in the past been mined in the island include bauxite, barite, gypsum, coal and high-grade aggregates.
In Northern Ireland, prospecting in recent years has been stimulated by the Tellus Project, managed by the Geological Survey of Northern Ireland. Between 2004 and 2007 this government-funded initiative completed soil and stream geochemical samples surveys and a low-level airborne geophysical survey of Northern Ireland, an area of 13,800 km2. Within 12 months of the data launch in 2007 the area of Northern Ireland licensed for exploration increased from 15% to 70% and the subsequent private sector investment in exploration now exceeds ÂŁ32 million. Targets include gold, platinum group elements and base metals. The project is a good example of how regional geo-science surveys can stimulate exploration activity and inward investment.
Historically the principal focus of prospecting in Northern Ireland has been the area of vein gold deposits in Neoproterozoic rocks of County Tyrone, centred on the deposits at Curraghinalt and Cavanacaw. Here, the airborne magnetic and electromagnetic results delineate significant associated structures. Arsenic in soils and stream sediments has been the principal geochemical pathfinder historically and the new sampling and analyses for multiple trace elements provide improved coverage at a better detection limit. Cross-border soil geochemical anomalies also characterise the area around the vein deposits in South Armagh and County Monaghan, in Ordovician/Silurian rocks. The geochemistry survey has revealed more widely distributed gold anomalies in stream sediments in other areas and mapped significant anomalies in platinum group elements over the Antrim basalts. Here again, the airborne magnetic and electromagnetic imagery reveal new structural information, particularly in those areas obscured by glacial deposits and peat.
Following this success, the airborne geophysics and geochemistry surveys have been extended over 12,300 km2 of the six border counties of the Republic of Ireland (Donegal, Sligo, Leitrim, Cavan, Monaghan and Louth) under the cross-border âTellus Borderâ project, financed by the INTERREG IVA programme of the European Regional Development Fund. This new survey work is jointly managed by the Geological Survey of Northern Ireland and the Geological Survey of Ireland. The integrated geophysical and geochemical results of Tellus and Tellus Border surveys are being released throughout 2013 and have prompted further interest in mineral prospectivity as well as environmental research into soils, surface and groundwater, radioactivity and ecology.
The project has stimulated joint data collection with the private sector. In 2012 the airborne survey was extended in eastern Co. Mayo and north Co. Roscommon in collaboration with a mining company, which has made the data publicly available. Another company has already taken out four licences on the basis of Tellus Border geochemical results released in February 2013. These data reveal the continuation of a trend established on adjoining licenses held in Northern Ireland. New fire-assay gold analyses of the Tellus Border stream sediment samples will be released in 2013. Together the merged Tellus and Tellus Border geochemical and geophysical data are expected to promote further investment in this cross-border region
Annual Research Review: interparental conflict and youth psychopathology: an evidence review and practice focused update
The quality of the interparental relationship is recognized as an important influence on child and adolescent psychopathology. Historically, clinically-oriented research on this topic has focused on the impacts of parental divorce and domestic violence as primary interparental relationship influences on child outcomes, to the relative neglect of dimensional or qualitative features of the couple/interparental relationship for youth (child and adolescent) psychopathology. Recent research has highlighted that children are affected by attributes of interparental conflict, specifically how parents express and manage conflicts in their relationship, across a continuum of expressed severity and negativity â ranging from silence to violence. Further, new evidence highlights that childrenâs emotional, behavioral, social, academic outcomes and future interpersonal relationships are adversely affected by conflict between parents/carers whether adults are living together or not (i.e. married or separated), or where children are or are not genetically related to their rearing parents (e.g. adoption). We review evidence and present an integrated theoretical model, highlighting how children are affected by interparental conflict and what this evidence base means for effective intervention and prevention program development, as well as the development of possible cost-benefit models. Additionally, we review policy implications of this research and highlight some very recent examples of UK-based policy focusing on addressing the interparental relationship and its impact on youth psychopathology
Independent estimation of input and measurement delays for a hybrid vertical spring-mass-damper via harmonic transfer functions
System identification of rhythmic locomotor systems is challenging due to the time-varying nature of their dynamics. Even though important aspects of these systems can be captured via explicit mechanics-based models, it is unclear how accurate such models can be while still being analytically tractable. An alternative approach for rhythmic locomotor systems is the use of data-driven system identification in the frequency domain via harmonic transfer functions (HTFs). To this end, the input-output dynamics of a locomotor behavior can be linearized around a stable limit cycle, yielding a linear, time-periodic system. However, few if any model-based or data-driven identification methods for time-periodic systems address the problem of input and measurement delays in the system. In this paper, we focus on data-driven system identification for a simple mechanical system and analyze its dynamics in the presence of input and measurement delays using HTFs. By exploiting the way input delays are modulated by the periodic dynamics, our results enable the separate, independent estimation of input and measurement delays, which would be indistinguishable were the system linear and time invariant. © 2015, IFAG
Diversity of the gut, vaginal and oral microbiome among pregnant women in South Africa with and without pre-eclampsia
The datasets presented in this study can be found in online
repositories. The names of the repository/repositories and accession number(s) can be found below: NCBI SRA database,
accession number PRJNA798597 (BioProjectID).BACKGROUND : Changes in microbial communities are a known characteristic of various inflammatory diseases and have been linked to adverse pregnancy outcomes, such as preterm birth. However, there is a paucity of information regarding the taxonomic composition and/or diversity of microbial communities in pre-eclampsia. The aim of this study was to determine the diversity of the gut, vaginal and oral microbiome in a cohort of South African pregnant women with and without pre-eclampsia. The diversity of the gut, vaginal and oral microbiome was determined by targeted next generation sequencing (NGS) of the V3 and V4 region of the 16S rRNA gene on the Illumina MiSeq platform. RESULTS : In this study population, pre-eclampsia was associated with a significantly higher alpha diversity (P = 0.0472; indicated by the Shannon index) in the vaginal microbiome accompanied with a significant reduction in Lactobacillus spp. (P = 0.0275), compared to normotensive pregnant women. Lactobacillus iners was identified as the predominant species of the vaginal microbiome in both cohorts. High inter-individual variation in alpha diversity was observed in the gut and oral microbiome in both cohorts. Although differences in the relative abundance of bacteria at all phylogenetic levels were observed, overall microbial composition of the gut, oral and vaginalmicrobiome was not significantly different in the pre-eclampsia cohort compared to the normotensive cohort. CONCLUSION : Collectively, a reduction of Lactobacillus spp., and predominance of L. iners in pregnant women with pre-eclampsia could suggest an unstable vaginal microbiome that might predispose pregnant women to develop pre- eclampsia. The lack of significant structural changes in the gut, oral and vaginal microbiome does not suggest that the characterized communities play a role in pre-eclampsia, but could indicate a characteristic unique to the study population. The current study provided novel information on the diversity of the gut, oral and vaginal microbiome among pregnant women in South Africa with and without pre-eclampsia. The current study provides a baseline for further investigations on the potential role of microbial communities in pre-eclampsia.The University of Pretoria and the National Health Laboratory Service (NHLS).https://www.frontiersin.org/journals/global-womens-healtham2023BiochemistryGeneticsMedical MicrobiologyMicrobiology and Plant Patholog
Cross-domain interference costs during concurrent verbal and spatial serial memory tasks are asymmetric
Some evidence suggests that memory for serial order is domain-general. Evidence also points to asymmetries in interference between verbal and visual-spatial tasks. We confirm that concurrently remembering verbal and spatial serial lists provokes substantial interference compared with remembering a single list, but we further investigate the impact of this interference throughout the serial position curve, where asymmetries are indeed apparent. A concurrent verbal order memory task affects spatial memory performance throughout the serial positions of the list, but performing a spatial order task affects memory for the verbal serial list only for early list items; in the verbal task only, the final items are unaffected by a concurrent task. Adding suffixes eliminates this asymmetry, resulting in impairment throughout the list for both tasks. These results suggest that domain-general working memory resources may be supplemented with resources specific to the verbal domain, but perhaps not with equivalent spatial resources
The lung microbiome in HIVâpositive patients with active pulmonary tuberculosis
Tuberculosis poses one of the greatest infectious disease threats of our time, especially when
associated with human immunodeficiency virus (HIV) infection. Very little data is available on the
lung microbiome in pulmonary tuberculosis (PTB) in HIV-positive patients. Three patient cohorts were
studied: (i) HIV-positive with no respiratory disease (control cohort), (ii) HIV-positive with pneumonia
and (iii) HIV-positive with PTB. Sputum specimens were collected in all patients and where possible a
paired BALF was collected. DNA extraction was performed using the QIAamp DNA mini kit (QIAGEN,
Germany) and extracted DNA specimens were sent to Inqaba Biotechnical Industries (Pty) Ltd for
16S rRNA gene sequence analysis using the Illumina platform (Illumina Inc, USA). Data analysis was
performed using QIMME II and R Studio version 3.6.2 (2020). The lung microbiomes of patients with
PTB, in the context of HIV co-infection, were dominated by Proteobacteria, Firmicutes, Actinobacteria
and Bacteroidetes. Loss of biodiversity and dysbiosis was found in these patients when compared
to the HIV-positive control cohort. Microbial community structure was also distinct from the control
cohort, with the dominance of genera such as Achromobacter, Mycobacterium, Acinetobacter,
Stenotrophomonas and Pseudomonas in those patients with PTB. This is the first study to describe
the lung microbiome in patients with HIV and PTB co-infection and to compare findings with an HIVpositive
control cohort. The lung microbiomes of patients with HIV and PTB were distinct from the
HIV-positive control cohort without PTB, with an associated loss of microbial diversity.DATA AVAILABILITY : The datasets generated and analysed during the current study are available in the University of Pretoria data
repository and can be accessed at https://doi.org/10.25403/UPresearchdata.19491317.v1.The Infectious diseases Research Fund.http://www.nature.com/scientificreportsam2023BiochemistryGeneticsInternal MedicineMedical MicrobiologyMicrobiology and Plant Patholog
Combinatorial activity of flavonoids with antibiotics against drug resistant Staphylococcus aureus
The use of resistance-modifying agents is a potential strategy that is used to prolong the effective life of antibiotics in the face of increasing antibiotic resistance. Since certain flavonoids are potent bacterial efflux pump inhibitors, we assessed morin, rutin, quercetin, hesperidin, and (+)-catechin for their combined activity with the antibiotics ciprofloxacin, tetracycline, erythromycin, oxacillin, and ampicillin against drug-resistant strains of Staphylococcus aureus, including methicillin-resistant S. aureus. Four established methods were used to determine the combined efficacy of each combination: microdilution checkerboard assays, time-kill determinations, the Etest, and dual disc-diffusion methods. The cytotoxicity of the flavonoids was additionally evaluated in a mouse fibroblast cell line. Quercetin and its isomer morin decreased by 3- to 16-fold the minimal inhibitory concentration of ciprofloxacin, tetracycline, and erythromycin against some S. aureus strains. Rutin, hesperidin, and (+)-catechin did not promote any potentiation of antibiotics. Despite the potential cytotoxicity of these phytochemicals at a high concentration (fibroblast IC50 of 41.8 and 67.5mg/L, respectively), quercetin is commonly used as a supplement for several therapeutic purposes. All the methods, with exception of the time-kill assay, presented a high degree of congruence without any apparent strain specificity.This work was supported by Operational Program for
Competitiveness FactorsâCOMPETE, FCT/MEC (PIDDAC),
and FEDER through Projects BioresistâPTDC/EBB-EBI/
105085/2008; PhytodisinfectantsâPTDC/DTP-SAP/1078/
2012 (COMPETE: FCOMP-01-0124-FEDER-028765) and
the PhD grants awarded to Ana Abreu (SFRH/BD/84393/
2012) and Anabela Borges (SFRH/BD/63398/2009). The
authors are very grateful to Professor Simon Gibbons (De-
partment of Pharmaceutical and Biological Chemistry, The
School of Pharmacy, UCL School of Pharmacy, London) for
providing the bacterial strains.info:eu-repo/semantics/publishedVersio
The Science of Sungrazers, Sunskirters, and Other Near-Sun Comets
This review addresses our current understanding of comets that venture close to the Sun, and are hence exposed to much more extreme conditions than comets that are typically studied from Earth. The extreme solar heating and plasma environments that these objects encounter change many aspects of their behaviour, thus yielding valuable information on both the comets themselves that complements other data we have on primitive solar system bodies, as well as on the near-solar environment which they traverse. We propose clear definitions for these comets: We use the term near-Sun comets to encompass all objects that pass sunward of the perihelion distance of planet Mercury (0.307 AU). Sunskirters are defined as objects that pass within 33 solar radii of the Sunâs centre, equal to half of Mercuryâs perihelion distance, and the commonly-used phrase sungrazers to be objects that reach perihelion within 3.45 solar radii, i.e. the fluid Roche limit. Finally, comets with orbits that intersect the solar photosphere are termed sundivers. We summarize past studies of these objects, as well as the instruments and facilities used to study them, including space-based platforms that have led to a recent revolution in the quantity and quality of relevant observations. Relevant comet populations are described, including the Kreutz, Marsden, Kracht, and Meyer groups, near-Sun asteroids, and a brief discussion of their origins. The importance of light curves and the clues they provide on cometary composition are emphasized, together with what information has been gleaned about nucleus parameters, including the sizes and masses of objects and their families, and their tensile strengths. The physical processes occurring at these objects are considered in some detail, including the disruption of nuclei, sublimation, and ionisation, and we consider the mass, momentum, and energy loss of comets in the corona and those that venture to lower altitudes. The different components of comae and tails are described, including dust, neutral and ionised gases, their chemical reactions, and their contributions to the near-Sun environment. Comet-solar wind interactions are discussed, including the use of comets as probes of solar wind and coronal conditions in their vicinities. We address the relevance of work on comets near the Sun to similar objects orbiting other stars, and conclude with a discussion of future directions for the field and the planned ground- and space-based facilities that will allow us to address those science topics
Comparative leaf anatomy and morphology of some Brazilian species of Crotalaria L. (Leguminosae: Papilionoideae: Crotalarieae)
Measurement of the branching fraction
The branching fraction is measured in a data sample
corresponding to 0.41 of integrated luminosity collected with the LHCb
detector at the LHC. This channel is sensitive to the penguin contributions
affecting the sin2 measurement from The
time-integrated branching fraction is measured to be . This is the most precise measurement to
date
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