bluuebunny/crossref_metadata_2025 huggingface dataset:
Early Gag Immunodominance of the HIV-Specific T-Cell Response during Acute/Early Infection Is Associated with Higher CD8
+
T-Cell Antiviral Activity and Correlates with Preservation of the CD4
+
T-Cell Compartment
Authors: Turk Gabriela , Ghiglione Yanina , Falivene Juliana , Socias María Eugenia , Laufer Natalia , Coloccini Romina Soledad , Rodriguez Ana María , Ruiz María Julia , Pando María Ángeles , Giavedoni Luis David , Cahn Pedro , Sued Omar , Salomon Horacio , Gherardi María Magdalena
Published: April 2013

The important role of the CD8
+
T-cell response on HIV control is well established. Moreover, the acute phase of infection represents a proper scenario to delineate the antiviral cellular functions that best correlate with control. Here, multiple functional aspects (specificity,
ex vivo
viral inhibitory activity [VIA] and polyfunctionality) of the HIV-specific CD8
+
T-cell subset arising early after infection, and their association with disease progression markers, were examined. Blood samples from 44 subjects recruited within 6 months from infection (primary HIV infection [PHI] group), 16 chronically infected subjects, 11 elite controllers (EC), and 10 healthy donors were obtained. Results indicated that, although Nef dominated the anti-HIV response during acute/early infection, a higher proportion of early anti-Gag T cells correlated with delayed progression. Polyfunctional HIV-specific CD8
+
T cells were detected at early time points but did not associate with virus control. Conversely, higher CD4
+
T-cell set points were observed in PHI subjects with higher HIV-specific CD8
+
T-cell VIA at baseline. Importantly, VIA levels correlated with the magnitude of the anti-Gag cellular response. The advantage of Gag-specific cells may result from their enhanced ability to mediate lysis of infected cells (evidenced by a higher capacity to degranulate and to mediate VIA) and to simultaneously produce IFN-γ. Finally, Gag immunodominance was associated with elevated plasma levels of interleukin 2 (IL-2) and macrophage inflammatory protein 1β (MIP-1β). All together, this study underscores the importance of CD8
+
T-cell specificity in the improved control of disease progression, which was related to the capacity of Gag-specific cells to mediate both lytic and nonlytic antiviral mechanisms at early time points postinfection.
A Conserved Gammaherpesvirus Protein Kinase Targets Histone Deacetylases 1 and 2 To Facilitate Viral Replication in Primary Macrophages
Authors: Mounce Bryan C. , Mboko Wadzanai P. , Bigley Tarin M. , Terhune Scott S. , Tarakanova Vera L.
Published: April 2013

Gammaherpesviruses are ubiquitious pathogens that establish lifelong infection and are associated with several malignancies. All gammaherpesviruses encode a conserved protein kinase that facilitates viral replication and chronic infection and thus represents an attractive therapeutic target. In this study, we identify a novel function of gammaherpesvirus protein kinase as a regulator of class I histone deacetylases (HDAC). Mouse gammaherpesvirus 68 (MHV68)-encoded protein kinase orf36 interacted with HDAC1 and 2 and prevented association of these HDACs with the viral promoter driving expression of RTA, a critical immediate early transcriptional activator. Furthermore, the ability to interact with HDAC1 and 2 was not limited to the MHV68 orf36, as BGLF4, a related viral protein kinase encoded by Epstein-Barr virus, interacted with HDAC1
in vitro
. Importantly, targeting of HDAC1 and 2 by orf36 was independent of the kinase's enzymatic activity. Additionally, orf36 expression, but not its enzymatic activity, induced changes in the global deacetylase activity observed in infected primary macrophages. Combined deficiency of HDAC1 and 2 rescued attenuated replication and viral DNA synthesis of the orf36 null MHV68 mutant, indicating that the regulation of HDAC1 and 2 by orf36 was relevant for viral replication. Understanding the mechanism by which orf36 facilitates viral replication, including through HDAC targeting, will facilitate the development of improved therapeutics against gammaherpesvirus kinases.
Conformational Plasticity of the 2A Proteinase from Enterovirus 71
Authors: Cai Qixu , Yameen Muhammad , Liu Weihua , Gao Zhenting , Li Yaozong , Peng Xuanjia , Cai Yaxian , Wu Caiming , Zheng Qian , Li Jian , Lin Tianwei
Published: April 2013

The 2A proteinase (2A
pro
) is an enterovirally encoded cysteine protease that plays essential roles in both the processing of viral precursor polyprotein and the hijacking of host cell translation and other processes in the virus life cycle. Crystallographic studies of 2A
pro
from enterovirus 71 (EV71) and its interaction with the substrate are reported here. EV71 2A
pro
was comprised of an N-terminal domain of a four-stranded antiparallel β sheet and a C-terminal domain of a six-stranded antiparallel β barrel with a tightly bound zinc atom. Unlike in other 2A
pro
structures, there is an open cleft across the surface of the protein in an open conformation. As demonstrated by the crystallographic studies and modeling of the complex structure, the open cleft could be fitted with the substrate. On comparison 2A
pro
of EV71 to those of the human rhinovirus 2 and coxsackievirus B4, the open conformation could be closed with a hinge motion in the bII2 and cII β strands. This was supported by molecular dynamic simulation. The structural variation among different 2A
pro
structures indicates a conformational flexibility in the substrate-binding cleft. The open structure provides an accessible framework for the design and development of therapeutics against the viral target.
Comparison of Viral Env Proteins from Acute and Chronic Infections with Subtype C Human Immunodeficiency Virus Type 1 Identifies Differences in Glycosylation and CCR5 Utilization and Suggests a New Strategy for Immunogen Design
Authors: Ping Li-Hua , Joseph Sarah B. , Anderson Jeffrey A. , Abrahams Melissa-Rose , Salazar-Gonzalez Jesus F. , Kincer Laura P. , Treurnicht Florette K. , Arney Leslie , Ojeda Suany , Zhang Ming , Keys Jessica , Potter E. Lake , Chu Haitao , Moore Penny , Salazar Maria G. , Iyer Shilpa , Jabara Cassandra , Kirchherr Jennifer , Mapanje Clement , Ngandu Nobubelo , Seoighe Cathal , Hoffman Irving , Gao Feng , Tang Yuyang , Labranche Celia , Lee Benhur , Saville Andrew , Vermeulen Marion , Fiscus Susan , Morris Lynn , Karim Salim Abdool , Haynes Barton F. , Shaw George M. , Korber Bette T. , Hahn Beatrice H. , Cohen Myron S. , Montefiori David , Williamson Carolyn , Swanstrom Ronald
Published: April 2013

Understanding human immunodeficiency virus type 1 (HIV-1) transmission is central to developing effective prevention strategies, including a vaccine. We compared phenotypic and genetic variation in HIV-1
env
genes from subjects in acute/early infection and subjects with chronic infections in the context of subtype C heterosexual transmission. We found that the transmitted viruses all used CCR5 and required high levels of CD4 to infect target cells, suggesting selection for replication in T cells and not macrophages after transmission. In addition, the transmitted viruses were more likely to use a maraviroc-sensitive conformation of CCR5, perhaps identifying a feature of the target T cell. We confirmed an earlier observation that the transmitted viruses were, on average, modestly underglycosylated relative to the viruses from chronically infected subjects. This difference was most pronounced in comparing the viruses in acutely infected men to those in chronically infected women. These features of the transmitted virus point to selective pressures during the transmission event. We did not observe a consistent difference either in heterologous neutralization sensitivity or in sensitivity to soluble CD4 between the two groups, suggesting similar conformations between viruses from acute and chronic infection. However, the presence or absence of glycosylation sites had differential effects on neutralization sensitivity for different antibodies. We suggest that the occasional absence of glycosylation sites encoded in the conserved regions of
env
, further reduced in transmitted viruses, could expose specific surface structures on the protein as antibody targets.
The value of the difference between ED and prehospital vital signs in predicting outcome in trauma
Authors: Bruijns Stevan R , Guly Henry R , Bouamra Omar , Lecky Fiona , Wallis Lee A
Published: April 2013

Introduction

Traditional vital signs are seen as an important part of trauma assessment, despite their poor predictive value in this regard.

Objective

This study evaluated whether the difference between systolic blood pressure (SBP), heart rate (HR), respiratory rate (RR) and shock index (SI) taken in the emergency department (ED) and prehospital can predict 48 h mortality postadmission following trauma.

Methods

Retrospective cohort was obtained from the Trauma Audit and Research Network. Subjects were excluded if head or spinal injuries, prehospital intubation or CPR were present. Main outcome was 48 h mortality. The difference (delta, Δ) between ED and prehospital values were used as study variables (ie, ΔSI=SI-ED minus SI-prehospital). Accuracy was assessed using area under receiver operator characteristic curve (AUROC). AUROC coordinates were used to identify 95% specificity cut points and described further using sensitivity and likelihood ratios (LRs).

Results

Significant AUROC statistics were revealed for ΔSBP (0.57) and ΔRR (0.56) for the full sample, ΔSBP (0.62) and ΔSI (0.65) for moderate, and ΔRR (0.6) for severe injury. Best LRs were 3.4 and 2.4 for ΔRR and ΔSI, respectively, but sensitivities were low (<=26%). Cut point values for ΔSBP, ΔRR and ΔSI were 37 mm Hg, 8 breaths/min and 0.2, respectively.

Discussion

ΔSBP and ΔRR performed best overall, but ΔSI performed best in the moderate injury group, suggesting earlier identification with ΔSI. Use of Δ values result in good rule-in of 48 h mortality and may supplement trauma treatment decisions.
Glycemic response varies between resistance and aerobic exercise in inactive males with long-term type 2 diabetes
Authors: Gordon Brett A. , Bird Stephen R. , MacIsaac Richard J. , Benson Amanda C.
Published: April 2013

The glycemic response to aerobic exercise is well understood; however, the response to resistance exercise is not. Eight inactive males (61.0 ± 7.2 years) with insulin-treated type 2 diabetes randomly completed single sessions of whole-body resistance exercise or cycling, 7 days apart. There were different 24-h glucose responses (p < 0.001) between the resistance exercise and the aerobic exercise, with short-term (24-h) impairment of glycemic control following the resistance exercise (p = 0.004). Cycling did not reduce glucose concentrations (p > 0.05), which contrasts with previous findings.
Synthesis and antiproliferative and c-Src kinase inhibitory activities of cinnamoyl- and pyranochromen-2-one derivatives
Authors: Chand Karam , Shirazi Amir Nasrolahi , Yadav Preeti , Tiwari Rakesh K. , Kumari Meena , Parang Keykavous , Sharma Sunil K.
Published: April 2013

A series of 6- and 8-cinnamoylchromen-2-one and dihydropyranochromen-2-one derivatives were synthesized and their antiproliferative activities were evaluated against three human cancer cell lines, i.e., ovarian adenocarcinoma (SK-OV-3), leukemia (CCRF-CEM), and breast carcinoma (MCF-7). In general, 8-cinnamoylchromen-2-one derivatives were found to have higher antiproliferative activity against the cancer cells when compared with 6-cinnamoyl analogues. Among all of the hybrid chromen-2-one − chalcone/flavanone compounds, a 7-hydroxy-8-cinnamoylchromen-2-one derivative 35 was found to be consistently active against all the cancer cell lines and inhibited the cell proliferation of SK-OV-3, CCRF-CEM, and MCF-7 by 63%, 50%, and 43%, respectively, at a concentration of 50 μmol/L after 72 h of incubation. This compound also exhibited the highest Src kinase inhibition (IC50= 14.5 μmol/L). Structure−activity relationship studies provided insights for designing the next generation of chromen-2-one − chalcone hybrid prototypes and the development of new leads as anticancer agents and (or) Src kinase inhibitors.
Gas chromatography − mass spectral characteristics of six pharmacologically active compounds — analytical performance characteristics on a raw sewage impacted water sample
Authors: Sichilongo Kwenga F. , Mutsimhu Cosmas , Obuseng Veronica C.
Published: April 2013

We have interrogated the characteristics of six pharmacologically active compounds in a hot gas chromatograph injector including some mass spectral characteristics in a quadrupole mass analyzer. The analytes are dimetridazole, metronidazole, chlorpromazine, trimethoprim, sulfamethazine, and dapsone. We have demonstrated the impact of the injector on the conversion efficiency of solvent to vapor in relation to analytes under investigation. The overall analytical performance of key parameters that were scrutinized and tested on a spiked raw sewer water sample using electron ionization (EI), positive chemical ionization (PCI), and negative chemical ionization (NCI) in the full and selected ion monitoring (SIM) scan modes are also presented. These parameters were the instrument detection limits (IDLs), method detection limits (MDLs), linearities, and percent recoveries. Correlation coefficients (R2) were greater than 0.9950 using all ionization and scan modes. Better MDLs were obtained using the SIM mode in all instances. The SIM mode MDLs ranged as follows: EI 0.308–0.711 and PCI 0.656–1.14 mg/L. Extremely good signals were observed in the NCI mode with dimetridazole and metronidazole where MDLs in the SIM mode were estimated to be 0.057 and 0.062 mg/L. Percent relative standard deviations (n = 3) were all less than 5% using EI employing full and SIM scan modes. Recoveries ranged from 55% to 96% in the full scan mode and from 67% to 94% in the SIM mode. Signal losses and ion population ratios in relation to the number of samples, i.e., scan speed and the mass scan range, are also interrogated.
Decline in growth rate of juvenile European plaice (Pleuronectes platessa) during summer at nursery beaches along the west coast of Scotland
Authors: Ciotti Benjamin J. , Targett Timothy E. , Burrows Michael T.
Published: April 2013

This study concludes that declines in growth rates of young-of-the-year European plaice (Pleuronectes platessa) (YOY plaice) during summer vary spatially and between years and that these dynamics are not driven by temperature, body size, or competition. RNA-predicted growth rates of YOY plaice on the west coast of Scotland declined linearly between mid-July and mid-September, with faster declines at beaches and in years where growth rates were initially high. Absolute growth estimates rarely approached ad libitum laboratory rates, and relative declines in growth rates were unrelated to temperature or body size allometry, indicating that maximum growth was rare. However, the absence of inverse relationships between spatial or temporal growth variation and YOY plaice or brown shrimp (Crangon crangon) densities suggests that competition did not limit growth. There were no consistent trends in morphometric condition factor, biochemical composition, or energy content during summer, indicating that apparent growth declines did not result from energy storage and did not result in depletion of energy stores. Influences of extrinsic factors (such as prey conditions, physical disturbance, and predator densities) on the diet, mediated by behavioral decisions to optimize growth with other ecological constraints, require further investigation as causes of growth variation in YOY plaice.
Estimating stand-scale biomass, nutrient contents, and associated uncertainties for tree species of Canadian forests
Authors: Paré David , Bernier Pierre , Lafleur Benoit , Titus Brian D. , Thiffault Evelyne , Maynard Doug G. , Guo Xiaojing
Published: April 2013

The growing demand for bioenergy feedstock from forest harvest residues is generating concerns about the potential loss of site productivity through nutrient removal. We used tree-level national biomass equations and a national database of forest plots to develop stand-level biomass equations for the different tree components of 30 major forest tree species found in Canada using basal area as the independent variable. We have also compiled more than 12 800 nutrient concentration values for different components of Canadian tree species from existing databases and the literature. Uncertainties were propagated across biomass equations and through conversion of nutrient concentrations to nutrient contents. Most of the uncertainty in nutrient contents estimates was found to be among the nutrient concentration measurements. The greatest levels of uncertainty were for estimates of phosphorus in woody components and of calcium in foliage. Grouping species into genera gave only a minor loss of precision. The coupling of biomass equations and nutrient concentration data can be used to provide first-order estimates of biomass and nutrients exported by tree component and species when harvesting any commercial stand in Canada. However, the associated uncertainties are important enough to warrant their inclusion in decision making.
Adiabatic quantum algorithms
Authors: Egger J. , McCurdy M. , Kyriakidis J.
Published: April 2013

We propose a notion of algorithm for adiabatic quantum computing for which one can coherently identify a notion of input, permitting a sensible notion of time complexity. We propose that time complexity bounds for adiabatic algorithms should be sought by examining the geometric structure of that portion of the relevant space of Hamiltonians for which the spectral gap is bounded below.
ELECTRONIC AND OPTICAL PROPERTIES OF PERFECT MgO AND MgO WITH F CENTER UNDER HIGH PRESSURE
Authors: ZHANG J. , ZENG Z.
Published: April 2013

A first-principle method is used to investigate the electronic structure and optical properties of MgO and MgO containing an oxygen vacancy. In the presence of the oxygen vacancy, a new electronic state appears in the band gap, which leads to additional peaks in the optical spectra. Furthermore, under applied pressure, the band gaps become larger, and the curves of optical properties including the dielectric function ε(ω) and absorption coefficient α(ω) shift towards higher energy. The knowledge of MgO and MgO with F center under high pressure may provide insight into their practical applications.
QUASI-ISOMETRY AND FINITE PRESENTATIONS OF LEFT CANCELLATIVE MONOIDS
Authors: GRAY ROBERT D. , KAMBITES MARK
Published: April 2013

We show that being finitely presentable and being finitely presentable with solvable word problem are quasi-isometry invariants of finitely generated left cancellative monoids. Our main tool is an elementary, but useful, geometric characterization of finite presentability for left cancellative monoids. We also give examples to show that this characterization does not extend to monoids in general, and indeed that properties such as solvable word problem are not isometry invariants for general monoids.
QUASI-TRIVIALITY OF QUANDLES FOR LINK-HOMOTOPY
Authors: INOUE AYUMU
Published: April 2013

We introduce the notion of quasi-triviality of quandles and define homology of quasi-trivial quandles. Quandle cocycle invariants are invariant under link-homotopy if they are associated with 2-cocycles of quasi-trivial quandles. We thus obtain a lot of numerical link-homotopy invariants.
FRACTAL PROPERTIES OF PARTICLES IN PHASE SPACE FROM URQMD MODEL
Authors: WANG X. , YANG C. B.
Published: April 2013

Nonstatistical dynamical fluctuations by means of the detrended fluctuation analysis (DFA) and multifractal DFA are studied. We used a two-dimensional algorithm for the analyses. By choosing different particles generated by UrQMD code, we show that different particles all have good scaling behaviors with bin size. The correlation between different identified particles are also discussed.
COMPUTATIONAL STUDY OF HIV-1 gp41 NHR TRIMER: INHIBITION MECHANISMS OF N-SUBSTITUTED PYRROLE DERIVATIVES AND FRAGMENT-BASED VIRTUAL SCREENING
Authors: BAO JU , LIU JIN F. , HE XIAO , ZHANG JOHN Z. H.
Published: April 2013

Fusion of HIV-1 viral and host cellular membranes is an important step for HIV infection. The HIV-1 envelope glycoprotein mediating the membrane fusion consists of subunits gp120 and gp41 whereas gp120 recognizes the cell-surface receptors and gp41 promotes viral-cell membrane fusion. The trimeric helical complex composed of heterodimer of N-terminal and C-terminal extraviral segments has been used for the gp41 function study, and the trimeric N-terminal teptad repeat (NHR) is considered as an antiviral drug target for developing HIV-1 membrane fusion inhibitors. By using computational solvent probe mapping, we have explored druggable sites on the trimeric NHR peptides, and identified residues K574 and R579 as the hot spots for inhibitor designing. We further demonstrated that although NB-2 and NB-64 are all N-substituted Pyrrole derivatives and have very similar chemical structures, it is possible that diverse inhibitory mechanisms targeting different negative electrostatic residues (K574 and R579) exist. Results from fragment-based virtual screening identified series of potential lead compounds which could be used for further design of fusion inhibitors.
FINITE RIGID SETS IN CURVE COMPLEXES
Authors: ARAMAYONA JAVIER , LEININGER CHRISTOPHER J.
Published: April 2013

We prove that curve complexes of surfaces are finitely rigid: for every orientable surface S of finite topological type, we identify a finite subcomplex 𝔛 of the curve complex [Formula: see text] such that every locally injective simplicial map [Formula: see text] is the restriction of an element of [Formula: see text], unique up to the (finite) pointwise stabilizer of 𝔛 in [Formula: see text]. Furthermore, if S is not a twice-punctured torus, then we can replace [Formula: see text] in this statement with the extended mapping class group Mod ±(S).
RIGHT LOCAL SEMIRINGS
Authors: Gupta Vishnu , Chaudhari Jayprakash Ninu
Published: April 2013

We prove the theorem: Let R be a CN-semiring. If R is right divisible two sided uniform semiring, then R is a right local semiring.
Exchange Rate Fundamentals and Order Flow
Authors: Evans Martin D. D. , Lyons Richard K.
Published: April 2013

We address whether transaction flows in foreign exchange markets convey fundamental information. Our General Equilibrium model includes fundamental information that first manifests at the micro level and is not symmetrically observed by all agents. This produces foreign exchange transactions that play a central role in information aggregation, providing testable links between transaction flows, exchange rates, and future fundamentals. We test these links using data on all end-user currency trades received at Citibank over 6.5 years, a sample sufficiently long to analyze real-time forecasts at the quarterly horizon. The predictions are borne out in four empirical findings that define this paper's main contribution: (1) transaction flows forecast future macro variables such as output growth, money growth, and inflation, (2) transaction flows forecast these macro variables significantly better than the exchange rate does, (3) transaction flows (proprietary) forecast future exchange rates, and (4) the forecasted part of fundamentals is better at explaining exchange rates than standard measured fundamentals.
Metal migration at the North Miitel Ni sulphide deposit in the southern Yilgarn Craton: Part 3, gas and overview
Authors: Noble R. R. P. , Lintern M. J. , Townley B. , Anand R. R. , Gray D. G. , Reid N.
Published: April 2013

Gases provide a known mechanism of metal migration through cover and a potential sampling medium to explore through cover that is under-utilised and under-studied. Understanding how metals move through transported cover and their link to buried deposits is critical information for successful mineral exploration in many regions of the world including the well-endowed Yilgarn Craton of Western Australia. Here we employ metal and hydrocarbon soil gas collection methods to successfully predict the location of the underlying North Miitel Ni ore body. Laboratory experiments to replicate soil moisture, hypergeometric evaluation and variable spacing tests were used to verify the gaseous Ni signature. Soil gas hydrocarbon analysis also reported an unqualified, but positive result. Integrating this study with previous research on soil, regolith, groundwater and vegetation chemistry in the study area enabled a model of anomaly formation to be derived explaining the observed results and the contributions of weathering, hydromorphic, biotic, aeolian and gaseous dispersion mechanisms operating at the North Miitel site. Weathering and hydromorphic dispersion are responsible for lateral and minor vertical Ni migration at depth, aeolian Ni is dispersed laterally near the road, whereas vegetation is cycling Ni in the shallow soils only. Results indicate a gaseous migration of Ni is responsible for vertical migration through cover at this site and provides a viable target for exploration through cover.
Metal migration at the North Miitel Ni sulphide deposit in the southern Yilgarn Craton: Part 1, regolith and groundwater
Authors: Noble R. R. P. , Lintern M. J. , Gray D. G. , Reid N. , Anand R.R.
Published: April 2013

Weathering and groundwater dispersion were studied at the North Miitel komatiite-hosted Ni sulphide deposit to understand the near-surface signature of this economically important mineralization style. Soil chemistry, regolith chemistry and groundwater chemistry show the secondary Ni enrichment is weak, limited primarily to the residual parent material and dispersed a few hundred metres laterally and only a few metres vertically above the water table. Partial extractions of soils did not enhance the visibility of the mineralisation to geochemistry. However, a subtle Ni anomaly was observed in the interface of the carbonate/clay accumulation at
c.
30–40  cm depth. The results show weathering and hydromorphic dispersion by groundwater are responsible for the large geochemical halo related to mineralisation at a depth of 10–20 m. A second mechanism involving gases or vegetation is proposed for the subtle near-surface anomaly. To successfully explore through transported cover it is essential to understand how surface anomalies form, what metals move and which sample media will best represent the buried ore signature. Here, groundwater provides the largest multielement target (Ni, Co, Pt and Pd), residual regolith is most accurately able to locate the mineralisation using Ni, and Ni in the soil clay/carbonate interface presents the easiest to collect but subtle surface geochemical signature of the primary ore which is buried 400 m below surface.
Rare earth element and gold exploration in glaciated terrain: example from the Mäkärä area, northern Finland
Authors: Sarapää Olli , Sarala Pertti
Published: April 2013

The Mäkärä Au-rare earth element (REE) prospect area is located in the Tana Belt, south of the 1.9 Ga Lapland Granulite Belt, in northern Finland. The Belt has prominent lanthanum (La) and yttrium (Y) anomalies in regional till and bedrock geochemical data. High Y indicates enrichment of heavy REE in the bedrock. At Mäkärä, promising narrow Au-hematite-quartz veins occur in connection with tensional fractures in the great shear zone.

Under the latest ice divide of the last glaciation, subglacial erosion was weak and glacial transport distance short. High Au contents in saprolite and till together with deep weathering have a strong positive correlation with the positive electromagnetic anomalies caused by the sulphidic gneisses. The highest La and Y contents in till correlate well with the Th maxima of airborne-radiometric datasets. Locally, the <0.06 mm till size fraction contains up to 0.4% REE. A recent exploration project in Mäkärä revealed a 13 m wide Au-hematite-quartz vein with a mean of 3 ppm Au and 0.04–0.1% REE in kaolinitic saprolite derived from arkosic gneiss. The elevated REE content resembles that of ionic adsorption clays in China. Typical REE-rich minerals are monazite, rhabdophane, xenotime and kaolinite. Till geochemistry proved useful in REE exploration.
Species diversity patterns in insular land snail communities of Borneo
Authors: Schilthuizen Menno , Liew Thor-Seng , Liew Thor-Hui , Berlin Patricia , King Jaqueline P. , Lakim Maklarin
Published: April 2013

Island biogeography, the study of distribution, richness and dynamics of species on isolated patches of habitat, is central to our understanding of what determines species diversity on Earth. Land snails are organisms particularly suited for answering questions pertaining to the factors that determine island species–area relationships, because of their dependence on edaphic conditions, low migration rates and high speciation rates. In this study, we analyse the land snail fauna in 73 standard quadrats of 20 m × 20 m on 13 islands of diverse geological origin off the coast of Sabah, northern Borneo, as well as one mainland site. We find a strong species–area relationship with slope (
z
-value) of 0.17. We also find that species abundance distributions for each island are best explained by a niche-based model. Finally, contrary to expectations, island area has a strong positive effect on point diversity within a 20 m × 20 m-quadrat. We discuss these results in the light of the relationship of area to population dynamics, habitat availability and primary productivity.

Supplementary materials:

The full quadrat-based data for all 98 snail species and goodness-of-fit (AIC-values) for five species abundance distribution models are available at
www.geolsoc.org.uk/SUP18550
.
Open-system processes in the differentiation of mafic magma in the Teide–Pico Viejo succession, Tenerife
Authors: Wiesmaier Sebastian , Troll Valentin R. , Wolff John A. , Carracedo Juan Carlos
Published: April 2013

Oceanic island basalts are commonly thought to differentiate by fractional crystallization, yet closed-system fractionation models have so far failed to reproduce major and trace element variations observed in mafic lavas from the Teide–Pico Viejo stratovolcano complex on Tenerife. Here, new high-precision plagioclase trace element data are fed into such a fractionation model. The results confirm that fractionation of phenocrysts found in the lavas does not reproduce trace element variations, in particular enrichment of Sr and Zr observed in the Teide–Pico Viejo mafic suite. This enrichment of Sr and Zr is tested by an energy-constrained recharge, assimilation and fractional crystallization (EC-RAFC) model at high
T
and low Δ
T
intervals, consistent with previously determined magma storage beneath Tenerife at sub-Moho depths. Published mineral–melt equilibrium relations using the plagioclase anorthite content (0.4 <
X
An
< 0.8) constrain the temperature during differentiation. Gabbroic xenoliths found in Tenerife lavas are assumed as contaminant. Enrichment of Sr and Zr in the Teide mafic suite is reproduced by this combined assimilation and fractional crystallization model, as assimilation causes higher degrees of enrichment in incompatible trace elements than is possible by crystal fractionation alone. Recycling of plutonic roots may thus have significantly enriched trace elements in the primitive lavas of the Teide–Pico Viejo succession.

Supplementary material:

Detailed average mineral compositions of low and high Sr–Zr lavas, composition of the bulk extracts and full graphs of the recalculated closed-system model are available at
www.geolsoc.org.uk/SUP18604
.
Geodynamics of the Middle East domain since the Oligocene: research summary
Authors: Mart Yossi
Published: April 2013

Several analogue models were merged to link the post-Oligocene closure of the Neotethys seaway with the break-up of the Gulf of Aden and the Red Sea. The seaway closure since the early Neogene, which was a result of northwards subduction of Neotethyan lithosphere under south–central Eurasia, generated two styles of kinematic convergence. Its western branch forms the Tethyan subduction under south–central Eurasia along the Hellenic deformation front, generating the break-up of the Aegean Sea and the westward migration of Anatolia. The eastern branch comprises the oblique convergence of Arabia with eastern Anatolia and Iran along the Bitlis–Zagros suture, which gradually shifted from subduction to collision. Because the velocity of plate collision is slower than that of subduction, the subducting section of the underthrust slab moves faster than the colliding segment. Consequently, the underthrust Arabian slab rotated counterclockwise, and developed detachment zones. Such extension triggered the resumption of the propagation of the Carlsberg Ridge into the Gulf of Aden, after being stalled for nearly 30 Ma. It is presumed further that the break-up of the Red Sea in the mid-Miocene was superimposed on the regional uplift and exhumation of the Arabo-Nubian Massif, which was caused by a mantle plume in the Oligocene, a plume that subsequently affected the Ethiopian and the East African plateaux in the Neogene.
Cenozoic reactivation of the Great Glen Fault, Scotland: additional evidence and possible causes
Authors: Le Breton E. , Cobbold P. R. , Zanella A.
Published: April 2013

The Great Glen Fault trends NNE–SSW across northern Scotland. According to previous studies, the Great Glen Fault developed as a left-lateral strike-slip fault during the Caledonian Orogeny (Ordovician to Early Devonian). However, it then reactivated right-laterally in the Tertiary. We discuss additional evidence for this later phase. At Eathie and Shandwick, minor folds and faults in fossiliferous Jurassic marine strata indicate post-depositional right-lateral slip. In Jurassic shale, we have found bedding-parallel calcite veins (‘beef’ and ‘cone-in-cone’) that may provide evidence for overpressure development and maturation of organic matter at significant depth. Thus, the Jurassic strata at Eathie and Shandwick accumulated deeper offshore in the Moray Firth and were subject to Cenozoic exhumation during right-lateral displacement along the Great Glen Fault, as suggested by previous researchers. Differential sea-floor spreading along the NE Atlantic ridge system generated left-lateral transpressional displacements along the Faroe Fracture Zone from the Early Eocene to the Late Oligocene (
c
. 47–26 Ma), a period of uplift and exhumation in Scotland. We suggest that such differential spreading was responsible for reactivation of the Great Glen Fault. Indeed, left-lateral slip along the Faroe Fracture Zone is compatible with right-lateral reactivation of the Great Glen Fault.
Sicily’s fold–thrust belt and slab roll-back: the SI.RI.PRO. seismic crustal transect
Authors: Catalano Raimondo , Valenti Vera , Albanese Cinzia , Accaino Flavio , Sulli Attilio , Tinivella Umberta , Gasparo Morticelli Maurizio , Zanolla Claudio , Giustiniani Michela
Published: April 2013

Sicily is a thick orogenic wedge formed by (1) the foreland (African) and its Sicilian orogen and (2) the thick-skinned, Calabrian–Peloritani wedge. The crust under central Sicily, from the Tyrrhenian margin to the coastline of the Sicily Channel, has been investigated by the multidisciplinary (SI.RI.PRO.) research project. The project dealt with the nature and thickness of the crust and depth and geometry of the Moho, which is essential in formulating subduction models and improving the knowledge of African and Tyrrhenian–European lithospheres. The results resolve features such as (1) the main orogenic wedge, (2) the very steep, NW–SE-trending regional monocline suggesting inflection of the foreland crust, (3) the deep Caltanissetta synform imaged, for the first time, to about 25 km, and (4) the top of the crystalline basement and the inferred crust–mantle boundary. The SI.RI.PRO. transect confirmed that the NNW-dipping, autochthonous Iblean platform of SE Sicily and its basement extends all the way into central Sicily. Further NW, towards the NNW end of the transect, a large uplift involves the Iblean platform and its underlying basement. The associated gravity anomaly is interpreted as the southern wedge edge of the Tyrrhenian mantle that splits the subducting Iblean–Pelagian (African) continental slab from an overlying synformal stack of allochthonous thrust sheets.

Supplementary materials:

Additional data are available at
www.geolsoc.org.uk/SUP18594
.
The evolution of the footwall to the Ronda subcontinental mantle peridotites: insights from the Nieves Unit (western Betic Cordillera)
Authors: Mazzoli S. , Martín-Algarra A. , Reddy S.M. , Sánchez-Vizcaíno V. López , Fedele L. , Noviello A.
Published: April 2013

Strongly heterogeneous deformation and extreme metamorphic gradients characterize the dominantly carbonate Nieves Unit in the footwall to the Ronda mantle extrusion wedge in the western Betic Cordillera. A well-developed foliation and mineral lineation, together with isoclinal intrafolial folds, occur in silicate-bearing, calcite or dolomite marbles within a
c
. 1.5 km thick metamorphic aureole underlying the peridotites. For the inferred maximum pressure of 300 MPa, petrological investigations allow us to define temperature ranges for the main zones of the metamorphic aureole: >510 °C (probably
c.
700 °C) for the forsterite zone; 510–430 °C for the diopside zone; 430–360 °C for the tremolite zone; 360–330 °C for the phlogopite zone. Field structural analysis integrated with petrological, microstructural and electron backscatter diffraction textural data document large finite strains consistent with general shear within the metamorphic aureole, associated with NW-directed thrusting of the peridotites. On the other hand, post-kinematic silicate growth suggests that heat diffusion from the high-temperature peridotites continued after the final emplacement of the Ronda mantle extrusion wedge, leading to final zoning of the metamorphic aureole and to local partial annealing of calcite marble textures, particularly in the highest-temperature zone of the thermally softened footwall carbonates. Following substantial cooling, renewed crustal shortening affected the whole Nieves Unit, resulting in widespread development of NE–SW-trending meso-scale folds.
The structural interpretation of domainal trace lineation: an example from the Mona Complex, Anglesey
Authors: Lisle Richard J.
Published: April 2013

Domainal trace lineation is defined by the intersection of two foliations, where at least one of these foliations is a composition banding formed by deformational processes (e.g. differentiated crenulation cleavage). The diagnostic feature of this lineation is a pronounced striping observed on the foliation surface that intersects the banding. An example of domainal trace lineation is displayed on the dominant foliation surfaces in New Harbour Group metasediments, near Rhoscolyn, Anglesey. The lineation is produced by the intersection of two foliations of domainal type, which produces prismatic domains resembling stretched objects. This probably explains the previous identifications of the lineation as a stretching lineation. The new interpretation of the lineation has potentially important implications for the deformation history of the New Harbour Group.
Origin and impact of authigenic chlorite in the Upper Cretaceous sandstone reservoirs of the Santos Basin, eastern Brazil
Authors: Bahlis Andréa B. , De Ros Luiz F.
Published: April 2013

Upper Cretaceous sandstones are the main clastic reservoirs of the Santos Basin, eastern Brazil, showing high porosity at depths greater than 4000 m. Porosity preservation in these deep sandstones is ascribed to the inhibition of quartz cementation and pressure dissolution by authigenic pore-lining chlorite. Santos sandstones are mostly fine-grained, lithic arkoses, rich in volcanic rock fragments (VRF). Chlorite, the most abundant diagenetic constituent, occurs as coatings, rims, rosettes and replacing grains. Chlorite precipitation was favoured by the presence of eodiagenetic smectite coatings and by the abundance of VRF. Detrital heavy minerals, biotite and mud intraclasts were also sources and/or substrates for chlorite authigenesis. The chloritization of VRF, biotite and heavy minerals resulted in precipitation of abundant TiO
2
minerals. Fluid flow patterns, burial and thermal history also played a role in chlorite authigenesis and reservoir quality evolution. Discontinuous and thin coatings and rims were not effective in inhibiting quartz cementation, while those too thick severely reduced the permeability. The rosette aggregates exerted no inhibition on quartz cementation, while reducing intergranular porosity. Systematic studies are necessary for modelling the diagenetic patterns of Santos Basin sandstones, in order to contribute to the reduction of risks involved in the exploration of these reservoirs.
GIS-based bivariate statistical modelling for earthquake-triggered landslides susceptibility mapping related to the 2008 Wenchuan earthquake, China
Authors: Xu Chong , Xu Xiwei , Yao Qi , Wang Yanying
Published: April 2013

The main purpose of this research is to evaluate the modelling capability and predictive power of a bivariate statistical method for earthquake-triggered landslide susceptibility mapping. A weight index (

W
i

) model was developed for the 2008 Wenchuan earthquake region in Sichuan Province, China, using a wide range of optical remote sensing data, and carried out on the basis of a geographic information system (GIS) platform. The 2008 Wenchuan earthquake triggered 196007 landslides, with a total area of 1150.43 km
2
, in an approximately oblong area around the Yingxiu–Beichuan coseismic surface fault-rupture (the Yingxiu–Beichuan fault). The landslides of the study area were mapped using visual interpretation of high-resolution satellite images and aerial photographs, both pre- and post-earthquake, and checked in the field at various locations. As a consequence, a nearly complete inventory of landslides triggered by the Wenchuan earthquake was constructed. Topographic and geological data and earthquake-related information were collected, processed and constructed into a spatial database using GIS and image processing technologies. A total of 10 controlling parameters associated with the earthquake-triggered landslides were selected, including elevation, slope angle, slope aspect, slope curvature, slope position, lithology, seismic intensity, peak ground acceleration (PGA), distance from the Yingxiu–Beichuan fault, and distance along this fault. To assist with the development of the model, the complete dataset of 196007 landslides was randomly partitioned into two subsets; a training dataset, which contains 70% of the data (137204 landslides, with a total area of 809.96 km
2
), and a testing dataset accounting for 30% of the data (58803 landslides, with a total area of 340.47 km
2
). A landslide susceptibility index map was generated using the training dataset, the 10 impact factors, and the

W
i

model. In addition, for a conditionally dependent factor analysis, seven other factor-combination cases were also used to construct landslide susceptibility index maps. Finally, these eight landslide susceptibility maps were compared with the training data and testing data to obtain model capability (success rate) and predictive power (predictive rate) information. The validation results show that the success and predictive rates of the

W
i

modelling exceeded 90% for the approaches that include the use of seismic factors. The final landslide susceptibility map can be used to identify and delineate unstable susceptibility-prone areas, and help planners to choose favourable locations for development schemes, such as infrastructure, construction and environmental protection schemes. The generic component of this research would allow application in other regions affected by high-intensity earthquakes and unstable terrain covering very large areas.
DRISTPI, a new groundwater vulnerability mapping method for use in karstic and non-karstic aquifers
Authors: Jiménez-Madrid A. , Carrasco F. , Martínez C. , Gogu R. C.
Published: April 2013

This paper proposes a new method, called DRISTPI, to evaluate the intrinsic vulnerability to contamination of different types of aquifers. Taking the DRASTIC method as a starting point, we highlight the need to define two scenarios to differentiate karst materials from the rest of the study area. The changes made in DRISTPI, with respect to DRASTIC, include the elimination of factors that are mainly related to the movement of water through the saturated zone of the aquifer (the original A and C factors) because the aim of this new method is to protect the groundwater (the resource) rather than the water supply (the source). Furthermore, the DRISTPI method incorporates a new factor called PI to characterize areas of preferential infiltration. Specifically, the vulnerability of two European aquifers with different geological, hydrogeological and climatic characteristics was evaluated using the DRISTPI method, and the results were compared with those obtained using DRASTIC, PI, COP, the Slovene Approach and PaPRIKa methods. These results were statistically analysed by confronting spatial autocorrelation coefficients to measure the cross-correlation between pairs of vulnerability maps.
Groundwater cooling of a large building using a shallow alluvial aquifer in Central London
Authors: Birks D. , Whittall S. , Savill I. , Younger P L. , Parkin G.
Published: April 2013

Shallow alluvial aquifers have been overlooked as thermal resources for low-carbon cooling in the UK. Most existing groundwater cooling systems in central London, for instance, use the deeply confined Chalk aquifer. Potential over-exploitation of the Chalk aquifer as a heat sink was one of the primary reasons why the River Terrace Gravels aquifer was investigated at the Tate Modern. Other considerations included a higher likelihood of achieving the required groundwater yields and the ability of the shallow River Terrace Gravels aquifer to dissipate heat more effectively than the deeper, confined Chalk. Where net heat rejection is large, the extent to which waste heat can escape the system is critical to the long-term sustainability of the scheme. Factors influencing heat loss include the thickness of cap rock and the ratio of surface area to thermal volume. Cost of scheme development in the River Terrace Gravels was also an important consideration and projected long-term energy savings as a result of sourcing water from a shallower aquifer, with lower pumping lifts, were considerable. Although circumstances where the River Terrace Gravels may be utilized for heating and cooling are limited owing to the restricted area underlain by these deposits, the variable saturation and potential vulnerability of basements to leakage if affected by raised groundwater levels in the vicinity of recharge wells, they may be a viable alternative to the Chalk for some locations. Continued monitoring of the operation of the Tate Modern scheme will provide further evidence of the viability of schemes using the Thames Gravels.
A review of small island hydrogeology: progress (and setbacks) during the recent past
Authors: Robins N. S.
Published: April 2013

Careful resource management is needed on small inhabited islands because demand can stress finite fresh groundwater reserves. Managers need to be informed how the groundwater system functions so that they can optimize the resource use and safeguard it from abuse. Hydrogeological investigation in small islands is broadly similar to basin studies on the mainland but small island scale coupled with data scarcity (including effective rainfall, permeability and baseflow) inhibit conventional groundwater flow modelling. Coastal and offshore baseflow measurement is the greatest uncertainty and research aims to better constrain its determination in the future. Small island hydrogeological investigations are challenging and aquifers can be classified as high-elevation hard fractured rock systems and low-relief karst limestone and sand islands. Although small island hydrogeological techniques have advanced considerably in the last 20 years, they must improve again in the future to help the many communities living in small island states that receive only erratic and unreliable rainfall recharge.