bluuebunny/crossref_metadata_2025_split huggingface dataset:
Individual Differences in Risky Decision Making: A Meta‐analysis of Sensation Seeking and Impulsivity with the Balloon Analogue Risk Task
Authors: Lauriola Marco , Panno Angelo , Levin Irwin P. , Lejuez Carl W. 
Published: April 2013

SUMMARYTo represent the state‐of‐the‐art in an effort to understand the relation between personality and risk taking, we selected a popular decision task with characteristics that parallel risk taking in the real world and two personality traits commonly believed to influence risk taking. A meta‐analysis is presented based on 22 studies of the Balloon Analogue Risk Task from which correlations with sensation seeking and impulsivity assessments could be obtained. Results calculated on a total of 2120 participants showed that effect size for the relation of sensation seeking with risk taking was in the small–moderate range ( = .14), whereas the effect size for impulsivity was just around the small effect size threshold ( = .10). Although we considered participants' demographics as moderators, we found only significantly larger effect sizes for the older adolescents and young adults compared with other ages. The findings of the present review supported the view that inconsistencies in personality–risk research were mostly due to random fluctuations of specific effect sizes, rather than to lack of theoretical ties or to measurement unreliability. It is also concluded that studies aimed at relating individual differences in personality to performance in experimental decision tasks need an appropriate sample size to achieve the power to produce significant results. Copyright © 2013 John Wiley & Sons, Ltd.
Comparison of the accuracy of Hybrid Capture II and polymerase chain reaction in detecting clinically important cervical dysplasia: a systematic review and meta‐analysis
Authors: Luu Hung N. , Dahlstrom Kristina R. , Mullen Patricia Dolan , VonVille Helena M. , Scheurer Michael E. 
Published: April 2013

AbstractThe effectiveness of screening programs for cervical cancer has benefited from the inclusion of Human papillomavirus (HPV) DNA assays; which assay to choose, however, is not clear based on previous reviews. Our review addressed test accuracy of Hybrid Capture II (HCII) and polymerase chain reaction (PCR) assays based on studies with stronger designs and with more clinically relevant outcomes. We searched OvidMedline, PubMed, and the Cochrane Library for English language studies comparing both tests, published 1985–2012, with cervical dysplasia defined by the Bethesda classification. Meta‐analysis provided pooled sensitivity, specificity, and 95% confidence intervals (CIs); meta‐regression identified sources of heterogeneity. From 29 reports, we found that the pooled sensitivity and specificity to detect high‐grade squamous intraepithelial lesion (HSIL) was higher for HCII than PCR (0.89 [CI: 0.89–0.90] and 0.85 [CI: 0.84–0.86] vs. 0.73 [CI: 0.73–0.74] and 0.62 [CI: 0.62–0.64]). Both assays had higher accuracy to detect cervical dysplasia in Europe than in Asia‐Pacific or North America (diagnostic odd ratio – dOR = 4.08 [CI: 1.39–11.91] and 4.56 [CI: 1.86–11.17] for HCII vs. 2.66 [CI: 1.16–6.53] and 3.78 [CI: 1.50–9.51] for PCR) and accuracy to detect HSIL than atypical squamous cells of undetermined significance (ASCUS)/ low‐grade squamous intraepithelial lesion (LSIL) (HCII‐dOR = 9.04 [CI: 4.12–19.86] and PCR‐dOR = 5.60 [CI: 2.87–10.94]). For HCII, using histology as a gold standard results in higher accuracy than using cytology (dOR = 2.87 [CI: 1.31–6.29]). Based on higher test accuracy, our results support the use of HCII in cervical cancer screening programs. The role of HPV type distribution should be explored to determine the worldwide comparability of HPV test accuracy.
Path Length Determines the Tunneling Decay of Substituted Carbenes
Authors: Kästner Johannes 
Published: April 2013

AbstractQuantum mechanical tunneling of atoms allows chemical reactions to proceed through barriers too high for thermally activated processes. This causes hydroxycarbenes to decay rapidly and at a temperature‐independent rate even at 11 K. In methylhydroxycarbene, tunneling causes decay through a mechanism that reveals a high but thin barrier rather than an alternative with a lower but broader barrier. No accurate estimates of the widths of such barriers and the lengths of tunneling paths were available. Herein, such a measure is provided by calculating the length of the tunneling paths by using instanton theory. Potential energies are provided by density functional theory verified by explicitly correlated coupled cluster CCSD(T) energies. Our results explain the decay efficiency in the known cases and suggest new substitutions to tune the effects of barrier widths and heights. Fluorination and replacement of the hydroxyl group by a thiol group change the qualitative character of the decay. Methylaminocarbene is predicted to be stable for thousands of years.
Stereoselective Aldol Addition to Rhenium(I) Complexes and Reversible Dimerization with Epimerization of the Metal Center
Authors: Álvarez Celedonio M. , Carrillo Romen , García‐Rodríguez Raúl , Miguel Daniel 
Published: April 2013

AbstractHerein, we report several examples of stereoselective aldol additions of aldehydes or ketones to ReI tricarbonyl complexes to form monomeric derivatives in good yields. The metal‐centered chirality defines the final stereochemistry of the carbon atom of the monomeric ReI complex after the addition. However, it cannot control the resulting stereochemistry of the enolate part, and thus, if the α‐carbon atom of the reagent is prochiral, a mixture of diastereoisomers is obtained. On the other hand, all of the monomeric complexes can be reversibly dimerized in basic media to form cis dimers, for which an epimerization of the metal‐centered chirality is required in order to avoid steric congestion. All of these results are supported by exhaustive crystallographic analysis.
Structural Principles and Thermoelectric Properties of Polytypic Group 14 Clathrate‐II Frameworks
Authors: Karttunen Antti J. , Fässler Thomas F. 
Published: April 2013

AbstractWe have investigated the structural principles and thermoelectric properties of polytypic group 14 clathrate‐II frameworks using quantum chemical methods. The experimentally known cubic 3C polytype was found to be the energetically most favorable framework, but the studied hexagonal polytypes (2 H, 4 H, 6 H, 8 H, 10 H) lie energetically close to it. In the case of germanium, the energy difference between the 3C and 6H clathrate‐II polytypes is ten times smaller than the difference between the experimentally known 3C‐Ge (α‐Ge) and 4H‐Ge polytypes. The thermoelectric properties of guest‐occupied clathrate‐II structures were investigated for compositions Na–Rb–Ga–Ge and Ge–As–I. The clathrate‐II structures show promising thermoelectric properties and the highest Seebeck coefficients and thermoelectric power factors were predicted for the 3C polytype. The structural anisotropy of the largest studied hexagonal polytypes affects their thermoelectric power factors by over a factor of two.
Functionalization of SnO2 Crystals with a Covalently‐Assembled Porphyrin Monolayer
Authors: Cristaldi Domenico A. , Gulino Antonino 
Published: April 2013

AbstractThe functionalization of micro‐ and nano‐sized metal‐oxide powders offers many advantages because of their large surface areas and, therefore, the large number of functional molecules that can be grafted onto the grain surfaces. Porphyrin molecules on large band‐gap semiconducting metal oxides represent key materials for many different optical and electronic applications. Herein, we have proposed a general two‐step procedure for the functionalization of metal‐oxide crystals with dye‐sensitizers. In particular, we functionalized SnO2 nanoparticles with a monolayer of the bifunctional trichloro[4‐(chloromethyl)phenyl]silane. Then, a monolayer of 5,10,15,20‐tetrakis(4‐hydroxyphenyl)‐21H,23H‐porphyne was covalently bound to the silanized SnO2 grains. IR, UV/Vis, and luminescence measurements were used for optical characterization. The measured footprint of the grafted porphyrin molecules indicated total surface coverage of the grains. The surface electronic characterization was performed by using X‐ray photoelectron spectroscopy. Emission measurements revealed two strong bands at 664.1 and 721.0 nm that were attributed to the porphyrin monolayer assembled on the surface of the SnO2 crystals.
Phase error analysis in CMOS injection‐coupled LC quadrature oscillator (IC‐QO)
Authors: Ghonoodi Hojat , Miar‐Naimi Hossein 
Published: April 2013

SummaryThis paper presents a novel approach to study the phase error in source injection coupled quadrature oscillators (QOs). Like other LC QOs, the mismatches between LC tanks are the main source of phase error in this oscillator. The QO is analyzed where the phase error and oscillation frequency are derived in terms of circuit parameters. The proposed analysis shows that the output phase error is a function of injection current and the current of source equivalent capacitor. As a result, it is shown that increasing of tail current and LC tank quality factor decreases the phase error. Derived equations show that the phase error can be cancelled and even controlled by adjusting bias currents. To evaluate the proposed analysis and consequent designed QO, a 5.5 GHz CMOS QO is designed and simulated using the practical 0.18 µm TSMC CMOS technology. The experiments show good agreement between analytical equations and simulation results. Copyright © 2013 John Wiley & Sons, Ltd.
Duplication and population dynamics shape historic patterns of selection and genetic variation at the major histocompatibility complex in rodents
Authors: Winternitz Jamie C. , Wares John P. 
Published: April 2013

AbstractGenetic variation at the major histocompatibility complex (MHC) is vitally important for wildlife populations to respond to pathogen threats. As natural populations can fluctuate greatly in size, a key issue concerns how population cycles and bottlenecks that could reduce genetic diversity will influenceMHCgenes. Using 454 sequencing, we characterized genetic diversity at theDRBClassIIlocus in montane voles (Microtus montanus), a North American rodent that regularly undergoes high‐amplitude fluctuations in population size. We tested for evidence of historic balancing selection, recombination, and gene duplication to identify mechanisms maintaining allelic diversity. Counter to our expectations, we found strong evidence of purifying selection acting on theDRBlocus in montane voles. We speculate that the interplay between population fluctuations and gene duplication might be responsible for the weak evidence of historic balancing selection and strong evidence of purifying selection detected. To further explore this idea, we conducted a phylogenetically controlled comparative analysis across 16 rodent species with varying demographic histories andMHCduplication events (based on the maximum number of alleles detected per individual). On the basis of phylogenetic generalized linear model‐averaging, we found evidence that the estimated number of duplicated loci was positively related to allelic diversity and, surprisingly, to the strength of purifying selection at theDRBlocus. Our analyses also revealed that species that had undergone population bottlenecks had lower allelic richness than stable species. This study highlights the need to consider demographic history and genetic structure alongside patterns of natural selection to understand resulting patterns of genetic variation at theMHC.
Convergence of tree water use and hydraulic architecture in water‐limited regions: a review and synthesis
Authors: Zeppel Melanie 
Published: April 2013

ABSTRACTGlobal vegetation models are used to estimate water and carbon fluxes in current and future climates. To accurately estimate these fluxes, it is crucial to incorporate tree processes, such as transpiration. Some models accurately predict fluxes in well‐watered conditions; however, our ability to predict responses of trees when water availability is limited remains restricted. Including mechanistic responses of trees during drought in models will improve estimates of water and carbon fluxes.Estimating water fluxes over large spatial scales may be calculated by combining (1) remotely sensed estimates of evapotranspiration with (2) knowledge of whether tree water use for a particular forest type or plant functional type follows universal scaling rules. There is little knowledge of whether universal scaling rules apply to water‐limited ecosystems.This review examines ‘convergence’ in relationships among tree water use, leaf area, and tree size, using Australian broad‐leaved evergreen vegetation as a case study. Broad‐leaved evergreen is a plant functional type commonly used in global vegetation models. If convergence is observed among leaf area and water use relationships for different species within this plant functional type, this would provide a powerful tool for scaling ecohydrological processes. This work tests the hypothesis that tree water use (Q) converges along a common relationship with leaf area for a continent‐wide range of species (n = 21), spanning a 100‐fold difference in size across broad‐leaved evergreens, including Acacia, Corymbia, and Eucalyptus as well as Callitris.Remarkably, the slope of the relationship between tree water use and leaf area was similar for the broad‐leaved evergreen genus, Eucalyptus, despite different slopes in relationships among diameter at breast height, leaf area, sapwood area, and Q. Realistic modelling of water and carbon fluxes requires an understanding of physiological mechanisms influencing Q, for each plant functional type, and for these mechanisms to be incorporated into vegetation models. Copyright © 2013 John Wiley & Sons, Ltd.
CD39 is involved in mediating suppression by Mycobacterium bovisBCG‐activated human CD8+CD39+ regulatory T cells
Authors: Boer Mardi C. , van Meijgaarden Krista E. , Bastid Jérémy , Ottenhoff Tom H.M. , Joosten Simone A. 
Published: April 2013

Regulatory T (Treg) cells can balance normal tissue homeostasis by limiting inflammatory tissue damage, e.g. during pathogen infection, but on the other hand can also limit protective immunity induced during natural infection or following vaccination. Because most studies have focused on the role of CD4+ Treg cells, relatively little is known about the phenotype and function of CD8+ Treg cells, particularly in infectious diseases. Here, we describe for the first time the expression of CD39 (E‐NTPDase1) on Mycobacterium‐activated human CD8+ T cells. These CD8+CD39+ T cells significantly co‐expressed the Treg markers CD25, Foxp3, lymphocyte activation gene‐3 (LAG‐3), and CC chemokine ligand 4 (CCL4), and suppressed the proliferative response of antigen‐specific CD4+ T helper‐1 (Th1) cells. Pharmacological or antibody mediated blocking of CD39 function resulted in partial reversal of suppression. These data identify CD39 as a novel marker of human regulatory CD8+ T cells and indicate that CD39 is functionally involved in suppression by CD8+ Treg cells.
Recent Developments in Low‐Dimensional Copper(II) Molecular Magnets
Authors: Landee Christopher P. , Turnbull Mark M. 
Published: April 2013

AbstractInvited for the cover of this issue is the group (current and recent students) of chemist Mark M. Turnbull and physicist Christopher P. Landee at Clark University. The image shows the types of low‐dimensional lattices under study and the everyday objects that inspired them.
Phosphane‐Catalyzed [3+2] Cycloaddition Reaction of Allenoate and Cyclic Imines: A Simple and Efficient Method for Synthesis of Benzo‐Fused Cyclic Sulfamidate Heterocycles
Authors: Wang You‐Qing , Zhang Yongna , Dong Haina , Zhang Jie , Zhao Jin 
Published: April 2013

AbstractBy using a phosphane as an organocatalyst, an efficient synthesis of benzo‐fused cyclic sulfamidate heterocycles has been developed through a cycloaddition reaction of allenoate and cyclic imines including cyclic trifluoromethyl ketimine, which gave high yields (71–97 %). The reaction could also be conveniently performed on a gram scale. Furthermore, some simple transformations of the sulfamidate heterocycle products have been disclosed to obtain functional amines. An asymmetric variant of this reaction was also tried by screening several commercially available chiral phosphane ligands as organocatalysts, and up to 36 % ee was achieved.
Role of two stage pyrolysis in fire growth on flexible polyurethane foam slabs
Authors: Pitts William M. 
Published: April 2013

SUMMARYA series of experiments designed to characterize fire behavior on flat 1.2 m × 1.2 m samples of commercial non‐fire‐retarded flexible polyurethane foam were performed. Time‐resolved heat release and mass loss rates were measured. Experimental parameters varied, including foam thickness (5.1 and 10.2 cm) and burning angle (+25°, +12.5°, 0°, −12.5°, and −25°). Polyurethane foam is typically produced by reacting a multifunctional isocyanate with a polyol. The foam used here was formed by reacting toluene diisocyanate and a polyol based on a condensed polyether of polypropylene oxide. Earlier cone calorimeter studies of this foam had revealed a clear two stage pyrolysis behavior in which the heated foam first released a gaseous fuel derived from the isocyanate component, while leaving behind a liquid produced primarily from the polyol, which only gasified and burned following additional heating. The subsequent burning behavior of the polyol‐derived liquid is shown in this work to play a crucial role in the maximum heat release rate and total heat released by the fires spreading across the foam slabs. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.
Evapotranspiration amplifies European summer drought
Authors: Teuling Adriaan J. , Van Loon Anne F. , Seneviratne Sonia I. , Lehner Irene , Aubinet Marc , Heinesch Bernard , Bernhofer Christian , Grünwald Thomas , Prasse Heiko , Spank Uwe 
Published: April 2013

AbstractDrought is typically associated with a lack of precipitation, whereas the contribution of evapotranspiration and runoff to drought evolution is not well understood. Here we use unique long‐term observations made in four headwater catchments in central and western Europe to reconstruct storage anomalies and study the drivers of storage anomaly evolution during drought. We provide observational evidence for the “drought‐paradox” in that region: a consistent and significant increase in evapotranspiration during drought episodes, which acts to amplify the storage anomalies. In contrast, decreases in runoff act to limit storage anomalies. Our findings stress the need for the correct representation of evapotranspiration and runoff processes in drought indices.
Effects of octreotide therapy in progressive head and neck paragangliomas: Case series
Authors: van Hulsteijn Leonie T. , van Duinen Nicolette , Verbist Berit M. , Jansen Jeroen C. , van der Klaauw Agatha A. , Smit Jan W. A. , Corssmit Eleonora P. M. 
Published: April 2013

BackgroundOctreotide, a somatostatin analog, may be beneficial in the treatment of head and neck paragangliomas (HNPGLs).MethodsWe conducted a nonblinded, prospective intervention study. During 1 year, patients received a monthly intramuscular injection of 30 mg octreotide. Pretreatment and posttreatment tumor volumes were assessed by MRI, urinary catecholamine secretion was measured, and HNPGL‐related signs and symptoms were recorded.ResultsIn 1 of 4 included patients with HNPGL, a stabilization of tumor growth was observed after octreotide therapy. In 1 patient, octreotide therapy was discontinued before the end of the study because of potential side effects. No improvements in HNPGL‐related signs and symptoms were observed.ConclusionIn 1 of 4 patients, HNPGL tumor growth velocity was reduced after octreotide therapy. Research assessing the effects of somatostatin analogues targeting different somatostatin receptor subtypes or combined with other therapies may offer new possibilities for the treatment of HNPGLs. © 2013 Wiley Periodicals, Inc. Head Neck 35: E391–E396, 2013
Disruption of LRP6 in osteoblasts blunts the bone anabolic activity of PTH
Authors: Li Changjun , Xing Qiujuan , Yu Bing , Xie Hui , Wang Weishan , Shi Chenhui , Crane Janet L , Cao Xu , Wan Mei 
Published: April 2013

ABSTRACT

Mutations in low-density lipoprotein receptor-related protein 6 (LRP6) are associated with human skeletal disorders. LRP6 is required for parathyroid hormone (PTH)-stimulated signaling pathways in osteoblasts. We investigated whether LRP6 in osteoblasts directly regulates bone remodeling and mediates the bone anabolic effects of PTH by specifically deleting LRP6 in mature osteoblasts in mice (LRP6 KO). Three-month-old LRP6 KO mice had a significant reduction in bone mass in the femora secondary spongiosa relative to their wild-type littermates, whereas marginal changes were found in femoral tissue of 1-month-old LRP6 KO mice. The remodeling area of the 3-month-old LRP6 KO mice showed a decreased bone formation rate as detected by Goldner's Trichrome staining and calcein double labeling. Bone histomorphometric and immumohistochemical analysis revealed a reduction in osteoblasts but little change in the numbers of osteoclasts and osteoprogenitors/osteoblast precursors in LRP6 KO mice compared with wild-type littermates. In addition, the percentage of the apoptotic osteoblasts on the bone surface was higher in LRP6 KO mice compared with wild-type littermates. Intermittent injection of PTH had no effect on bone mass or osteoblastic bone formation in either trabecular and cortical bone in LRP6 KO mice, whereas all were enhanced in wild-type littermates. Additionally, the anti-apoptotic effect of PTH on osteoblasts in LRP6 KO mice was less significant compared with wild-type mice. Therefore, our findings demonstrate that LRP6 in osteoblasts is essential for osteoblastic differentiation during bone remodeling and the anabolic effects of PTH. © 2013 American Society for Bone and Mineral Research.
The sonographic “coffee bean” sign helps distinguish an axillary neurofibroma from a lymphadenopathy
Authors: Song Sung Eun , Seo Bo Kyoung , Choi Jung‐Woo , Son Gil‐Soo , Cho Kyu Ran , Kim Baek Hyun 
Published: April 2013

ABSTRACTAxillary masses may represent various soft tissue tumors or lymphadenopathy. Neurofibromas are benign peripheral nerve sheath tumors and, while they are very uncommon, it is important to remember that neurogenic tumors arising from brachial plexus can develop in the axilla. We describe an axillary neurofibroma arising from the brachial plexus that presented with a “coffee bean sign” on sonography that distinguished it from axillary lymphadenopathy. © 2013 Wiley Periodicals, Inc. J Clin Ultrasound 42:33–37, 2014
Variability in eruption style and associated very long period events at Fuego volcano, Guatemala
Authors: Waite Gregory P. , Nadeau Patricia A. , Lyons John J. 
Published: April 2013

AbstractRepeated short‐term deployments of seismic, infrasound, video, and gas‐emission instruments at Fuego volcano, Guatemala have revealed three types of very long period (VLP) events associated with conduit sealing, pressure accumulation, and release. In 2008, ash‐rich explosions issued from a vent on the western flank and produced one type of VLP (Type 1). Impulsive, bomb‐rich explosions from the summit vent in 2009 produced a shorter period VLP (Type 2), but also generated ash release. Type 3 VLP events occurred during ash‐free exhalations from the summit in 2008 and had waveform shapes similar to Type 2 events. Weak infrasound records for Type 1 explosions compared to Type 2 suggest lower pressures and higher magma porosity for Type 1. Type 3 events correlate with spikes in SO2 emission rate and are driven by partial sealing and rapid release of ash‐free gas at the summit vent. Variations in the VLP period may provide a new tool for monitoring conditions within the conduit.