bluuebunny/crossref_metadata_2025 huggingface dataset:
One‐Pot Synthesis and Applications of N‐Heteroaryl Iodonium Salts
Authors: Bielawski Marcin , Malmgren Joel , Pardo Leticia M. , Wikmark Ylva , Olofsson Berit
Published: January 2014

An efficient one‐pot synthesis of N‐heteroaryl iodonium triflates from the corresponding N‐heteroaryl iodide and arene has been developed. The reaction conditions resemble our previous one‐pot syntheses, with suitable modifications to allow N‐heteroaryl groups. The reaction time is only 30 min, and no anion exchange is required. The obtained iodonium salts were isolated in a protonated form, these salts can either be employed directly in applications or be deprotonated prior to use. The aryl groups were chosen to induce chemoselective transfer of the heteroaryl moiety to various nucleophiles. The reactivity and chemoselectivity of these iodonium salts were demonstrated by selectively introducing a pyridyl moiety onto both oxygen and carbon nucleophiles in good yields.
The jmzQuantML programming interface and validator for the mzQuantML data standard
Authors: Qi Da , Krishna Ritesh , Jones Andrew R
Published: January 2014

The mzQuantML standard from the HUPO Proteomics Standards Initiative has recently been released, capturing quantitative data about peptides and proteins, following analysis of MS data. We present a Java application programming interface (API) for mzQuantML called jmzQuantML. The API provides robust bridges between Java classes and elements in mzQuantML files and allows random access to any part of the file. The API provides read and write capabilities, and is designed to be embedded in other software packages, enabling mzQuantML support to be added to proteomics software tools (http://code.google.com/p/jmzquantml/). The mzQuantML standard is designed around a multilevel validation system to ensure that files are structurally and semantically correct for different proteomics quantitative techniques. In this article, we also describe a Java software tool (http://code.google.com/p/mzquantml‐validator/) for validating mzQuantML files, which is a formal part of the data standard.
Parametric Influences on the Sensitivity of Exploding Foil Initiators
Authors: Chen Qing‐Chou , Fu Qiu‐Bo , Chen Lang , Han Zhong‐Fei
Published: January 2014

Analyses of firings by the up‐and‐down method were employed to gain a better understanding of the influences of foil bridge width, foil thickness, flyer thickness, and barrel length on the sensitivity of exploding foil initiators. Characterization was performed via the mean threshold voltage. The results showed that the mean threshold voltage of exploding foil initiators was reduced by 16 % when the foil bridge width was reduced from 0.4 mm to 0.3 mm, which means that a reduced foil bridge width could decrease the mean threshold voltage of exploding foil initiators as suggested by theoretical analysis. The mean threshold voltage of exploding foil initiators was reduced by 20 % as the flyer thickness was decreased from 50 μm to 25 μm, which could be an efficient way to improve the sensitivity of exploding foil initiators. The flyer accelerated to over 90 % maximum velocity after flying 0.15 mm in a fine barrel, which revealed that exceeding a barrel length of 0.15 mm has little effect on the performance of exploding foil initiators.
Indigenous American species of the Bemisia tabaci complex are still widespread in the Americas
Authors: Barbosa Leonardo da F , Marubayashi Julio M , De Marchi Bruno R , Yuki Valdir A , Pavan Marcelo A , Moriones Enrique , Navas‐Castillo Jesús , Krause‐Sakate Renate
Published: January 2014

Bemisia tabaci is a complex of at least 36 putative cryptic species. Since the late 1980s, the Middle East–Asia Minor 1 species (MEAM1, formerly known as the B biotype), has emerged in many tropical and subtropical regions of the world and in some areas has displaced the indigenous populations of B. tabaci. Based on analysis of the mtCOI gene, two indigenous species native to America have been reported: New World (NW, formerly the A biotype) and New World 2 (NW2). NW is present at least in Argentina, Brazil, Martinique, Mexico, Texas and Venezuela, and NW2 in Argentina, Bolivia and Brazil. Wild plants (Euphorbia sp. and Ipomoea sp.), as well as important crops such as tomato, bean and cotton, are still hosts for native B. tabaci populations in the Americas. MEAM1 has not completely displaced the native B. tabaci from the Americas. © 2014 Society of Chemical Industry
Aerosol emitters disrupt codling moth, Cydia pomonella, competitively
Authors: McGhee Peter S. , Gut Larry J. , Miller James R.
Published: January 2014

BACKGROUND

Isomate® CM MIST aerosol emitters (Pacific BioControl Corp, Vancouver, WA) containing 36 g of codlemone, (E,E)‐8,10‐dodecadien‐1‐ol, were deployed at various densities in a commercial apple orchard to generate dosage–response profiles in order to elucidate the behavioral mechanism of disruption.

RESULTS

Moth captures decreased asymptotically as Isomate® CM MIST densities increased. Data fitting to Miller–Gut and Miller–de Lame plots yielded straight lines, with positive and negative slopes respectively. Catch of male moths decreased from 28 trap−1 in the control to 0.9 trap−1 at the highest emitter density. Disruption of >90% was realized at emitter densities greater than 5 units ha−1.

CONCLUSION

The resulting set of profiles explicitly matched the predictions for competitive rather than non‐competitive disruption. Thus, these devices probably disrupt by inducing false‐plume following rather than by camouflaging traps and females. The use of 5 MIST units ha−1 would be necessary to achieve the same level of codling moth control provided by a standard pheromone treatment with passive reservoir dispensers. The need for only a few aerosol emitters, 2.5–5 units ha−1, mitigates the cost of labor required to hand‐apply hundreds of passive reservoir dispensers; however, a potential weakness in using this technology is that the low deployment density may leave areas of little or no pheromone coverage, where mate finding may occur. This technology is likely to benefit substantially from treatment of large contiguous blocks of crop. © 2014 Society of Chemical Industry
Genetic structure of Bemisia tabaci Med populations from home‐range countries, inferred by nuclear and cytoplasmic markers: impact on the distribution of the insecticide resistance genes
Authors: Gauthier Nathalie , Clouet Cécile , Perrakis Andreas , Kapantaidaki Despoina , Peterschmitt Michel , Tsagkarakou Anastasia
Published: January 2014

BACKGROUND

Insecticide resistance management in Bemisia tabaci is one of the main issues facing agricultural production today. An extensive survey was undertaken in five Mediterranean countries to examine the resistance status of Med B. tabaci species in its range of geographic origin and the relationship between population genetic structure and the distribution of resistance genes. The investigation combined molecular diagnostic tests, sequence and microsatellite polymorphism studies and monitoring of endosymbionts.

RESULTS

High frequencies of pyrethroid (L925I and T929V, VGSC gene) and organophosphate (F331W, ace1 gene) resistance mutations were found in France, Spain and Greece, but not in Morocco or Tunisia. Sequence analyses of the COI gene delineated two closely related mitochondrial groups (Q1 and Q2), which were found either sympatrically (Spain) or separately (France). Only Q1 was observed in Greece, Morocco and Tunisia. Bayesian analyses based on microsatellite loci revealed three geographically delineated genetic groups (France, Spain, Morocco/Greece/Tunisia) and high levels of genetic differentiation even between neighbouring samples. Evidence was also found for hybridisation and asymmetrical gene flow between Q1 and Q2.

CONCLUSIONS

Med B. tabaci is more diverse and structured than reported so far. On a large geographic scale, resistance is affected by population genetic structure, whereas on a local scale, agricultural practices appear to play a major role. © 2014 Society of Chemical Industry
A Hybrid Lattice Boltzmann Method–Finite Difference Method Model for Sediment Transport and Riverbed Deformation
Authors: Liu H. , Ding Y. , Li M. , Lin P. , Yu M. H. , Shu A. P.
Published: January 2014

In this study, a two‐dimensional hybrid numerical model for sediment transport based on lattice Boltzmann method and finite difference method is presented. The governing equations for water flow and suspended sediment transport are the shallow water equations and the advection–diffusion equations, respectively. Sediment load is also involved, so that riverbed deformation is numerically simulated. The model is verified by testing transportation of bank‐slump sediment in a sharp bended channel with the comparison to the results of well‐accepted finite volume method, illustrating the effectiveness of the proposed hybrid model. Copyright © 2014 John Wiley & Sons, Ltd.
Immobilisation of cell‐binding peptides on poly‐ε‐caprolactone (PCL) films: A comparative XPS study of two chemical surface functionalisation methods
Authors: Stevens Joanna S. , de Luca Alba C. , Downes Sandra , Terenghi Giorgio , Schroeder Sven L. M.
Published: January 2014

Successful interaction between cells and biomaterial surfaces is crucial for biomedical devices, and incorporation of peptides such as RGD (Arg‐Gly‐Asp) at the polymer interface can substantially promote cell adhesion and proliferation. X‐ray photoelectron spectroscopy (XPS) has been used to characterise poly‐ε‐caprolactone (PCL) films modified by aminolysis and the introduction of RGD peptides via carbodiimide (CDI) and thiol‐halogen ‘click’ chemistry. The nitrogen signal acts as an elemental indicator for successful attachment, and changes in the chemical environment are reflected in the carbon and oxygen spectra. Chlorine and sulfur provide additional chemical indicators of reaction progress in the thiol method, with the selective nature of the Cl–S reaction reflected in the complete loss of Cl signal and appearance of S, avoiding potential amine‐peptide side‐reactions. Comparison of the XPS elemental concentrations indicated an estimate of 2–3% peptide functionalisation on the PCL surface for both methods, correlating with the improvement in Schwann cell response observed after peptide immobilisation. The enhanced selectivity of peptide attachment to the polymer surface demonstrated with XPS for the novel method based on thiol chemistry shows its potential for development as a biomimetic scaffold for peripheral nerve injury. Copyright © 2014 John Wiley & Sons, Ltd.
Longitudinal Analysis of Academic Burnout in Korean Middle School Students
Authors: Kim Boyoung , Lee Minyoung , Kim Keunhwa , Choi Hyunju , Lee Sang Min
Published: January 2014

The purpose of the study was to investigate the longitudinal relationships between the initial values and slopes of three dimensions of burnout syndrome (i.e. emotional exhaustion, cynicism and academic inefficacy). The study utilized four‐wave longitudinal data from a total of 367 (81.6% response rate) middle school students in South Korea. Comprising a 6‐month interval survey, the first survey was conducted in June 2010, the second in December 2010, the third in June 2011 and the fourth in December 2011. All participants were 13‐year‐olds at the first and second surveys, and 14‐year‐olds at the third and fourth surveys. The Maslach Burnout Inventory—Student Survey was used for each survey to assess the level of academic burnout. The longitudinal data were analysed using latent growth modelling. The results of the study indicated that high initial values (intercept) for emotional exhaustion were associated with a higher rate of increase (slope) in cynicism and academic inefficacy. On the other hand, high initial values for cynicism and academic inefficacy were associated with a lower rate of increase in the other dimensions. This longitudinal study should promote understanding of burned‐out students and contribute to the literature by informing the design of prevention programmes for academic burnout. Copyright © 2014 John Wiley & Sons, Ltd.
Surface boxplots
Authors: Genton Marc G. , Johnson Christopher , Potter Kristin , Stenchikov Georgiy , Sun Ying
Published: January 2014

In this paper, we introduce a surface boxplot as a tool for visualization and exploratory analysis of samples of images. First, we use the notion of volume depth to order the images viewed as surfaces. In particular, we define the median image. We use an exact and fast algorithm for the ranking of the images. This allows us to detect potential outlying images that often contain interesting features not present in most of the images. Second, we build a graphical tool to visualize the surface boxplot and its various characteristics. A graph and histogram of the volume depth values allow us to identify images of interest. The code is available in the supporting information of this paper. We apply our surface boxplot to a sample of brain images and to a sample of climate model outputs. Copyright © 2014 John Wiley & Sons Ltd.
Biaxial behaviour of plain concrete subjected to dynamic compression with constant lateral stress
Authors: Yan Dongming , Xu Shilang , Chen Genda , Li Hedong
Published: January 2014

This study investigates the dynamic biaxial behaviour of concrete by testing more than 60 cubic specimens on a custom‐designed, servo‐hydraulic‐controlled machine. Each specimen was axially loaded in compression at a constant strain rate of 10–5, 10–4, 10–3 or 10–2 s–1 while two opposite side faces were subjected to a constant confining pressure and the other two side faces were free. The confining pressure applied to each specimen was 0, 30.5, 61.0 or 91.5 % of its uniaxial compressive strength. Test results indicate that the biaxial strength of concrete increases with strain rate at a reduced slope as confining pressure increases. The failure mode of the concrete specimens was basically unaffected by the strain rate. An empirical relation for the ultimate strength of concrete in a biaxial stress state was developed taking into account the effects of both confinement and strain rate.
Effects of antidepressant drug exposure on gene expression in the developing cerebral cortex
Authors: Tsapakis Evangelia M. , Fernandes Cathy , Moran‐Gates Taylor , Basu Amlan , Sugden Karen , Aitchison Katherine J. , Tarazi Frank I.
Published: January 2014

To clarify the basis of limited responses in children and adolescents to antidepressant treatments considered standard in the treatment of adult major depressive disorder, juvenile Sprague–Dawley rats were subjected to 21‐day treatment with dissimilar antidepressant drugs fluoxetine, imipramine, or vehicle control. Total RNA was extracted from brain frontal cortices and hybridized to the Affymetrix 230.2 chip. A total of 18 microarrays were analyzed (i.e., six biological replicates in three treatment groups). Transcripts identified were validated using Taqman real‐time quantitative PCR methodology, and the relative expression of each gene was also determined. In both the imipramine‐ and fluoxetine‐treated animals, expression of six genes was down‐regulated (ANOVA‐filtered gene expression data using dChip [version 2005]): Gpd1; Lrrn3; Sult1A1; Angptl4; Mt1a; Unknown. Furthermore, four genes were over‐expressed: P4Ha1; RDG1311476; Rgc32; and SLC25A18‐like by both imipramine and fluoxetine. These data demonstrate that antidepressant drugs interfere with the expression of genes involved in cell signaling, survival, and protein metabolism. Our results show that antidepressants regulate the induction of highly specific transcriptional programs in the developing frontal cortex. These findings provide novel insights into the long‐term molecular actions of antidepressant drugs in the developing brain. Synapse 68:209–220, 2014. © 2014 Wiley Periodicals, Inc.
Resting‐state functional connectivity MRI reveals active processes central to cognition
Authors: Stevens W. Dale , Spreng R. Nathan
Published: January 2014

Analysis of spontaneously correlated low‐frequency activity fluctuations across the brain using functional magnetic resonance imaging (MRI)—commonly referred to as resting‐state functional connectivity (RSFC) MRI—was initially seen as a useful tool for mapping functional‐anatomic networks in the living human brain, characterizing brain changes and differences in clinical populations, and studying comparative anatomy across species. However, little was known about the potential relevance of RSFC to cognitive processes. Indeed, there has been considerable controversy and debate as to the utility of studying the resting‐state in cognitive neuroscience. However, recent work has shown that RSFC, rather than merely reflecting passive or epiphenomenal activity within underlying functional‐anatomic networks, reveals important dynamic processes that play an active role in cognition. RSFC has been associated with individual differences in a number of behavioral and cognitive domains, including perception, language, learning and memory, and the organization of conceptual knowledge. In this article, we review and integrate the latest research demonstrating that RSFC is functionally relevant to human behavior and higher‐level cognition, and propose a hypothesis regarding its mechanism of action on functional network dynamics and cognition. We conclude that RSFC MRI will be an invaluable tool for future discovery of the fundamental neurocognitive interactions that underlie cognition. WIREs Cogn Sci 2014, 5:233–245. doi: 10.1002/wcs.1275

This article is categorized under:

Neuroscience > Cognition

Neuroscience > Physiology

Neuroscience > Plasticity
The dreams of theory
Authors: Crutchfield James P.
Published: January 2014

Computing power and sophisticated data acquisition mask the fact that, in many sciences and engineering, the balance between theory and experiment is getting increasingly out of whack. The imbalance becomes an even greater concern in light of the increasingly complex natural systems science now confronts and the increasingly complex and interdependent sociotechnical systems modern engineering allows us to construct. Given its critical role in understanding such complex systems, Big Theory deserves a place alongside Big Data and Big Iron, says Jim Crutchfield. WIREs Comput Stat 2014, 6:75–79. doi: 10.1002/wics.1290

This article is categorized under:

Software for Computational Statistics > Artificial Intelligence and Expert Systems

Applications of Computational Statistics > Education in Computational Statistics
Understanding principles of miRNA target recognition and function through integrated biological and bioinformatics approaches
Authors: Carroll Adam P. , Goodall Gregory J. , Liu Bing
Published: January 2014

In recent times, microRNA (miRNA) have emerged as primary regulators of fundamental biological processes including cellular differentiation, proliferation, apoptosis, as well as synaptic plasticity. However, miRNAs bind their targets with only partial complementarity, making it very challenging to determine exactly how a miRNA is functioning in specific biological environments. This review discusses key principles of miRNA target recognition and function which have emerged through the progressive advancement of biological and bioinformatics approaches. Ultimately, the integration of gene expression and biochemical methods with sequence‐ and systems‐based bioinformatics approaches will reveal profound insights regarding the importance of target contextual features in determining miRNA target recognition and regulatory outcome, as well as the importance of RNA interaction networks in enabling miRNA to regulate different target genes and functions in specific biological contexts. There is therefore a demand for the elegant design of future experiments such that principles of context‐specific miRNA target recognition and regulatory outcome can be accurately modeled in normal developmental and disease states.

This article is categorized under:

RNA Evolution and Genomics > Computational Analyses of RNA

RNA Interactions with Proteins and Other Molecules > Small Molecule–RNA Interactions

Regulatory RNAs/RNAi/Riboswitches > RNAi: Mechanisms of Action
Blended learning in health education: three case studies
Authors: De Jong Nynke , Savin-Baden Maggi , Cunningham Anne Marie , Verstegen Danie¨lle M. L.
Published: January 2014

Blended learning in which online education is combined with face-to-face education is especially useful for (future) health care professionals who need to keep up-to-date. Blended learning can make learning more efficient, for instance by removing barriers of time and distance. In the past distance-based learning activities have often been associated with traditional delivery-based methods, individual learning and limited contact. The central question in this paper is: can blended learning be active and collaborative? Three cases of blended, active and collaborative learning are presented. In case 1 a virtual classroom is used to realize online problem-based learning (PBL). In case 2 PBL cases are presented in Second Life, a 3D immersive virtual world. In case 3 discussion forums, blogs and wikis were used. In all cases face-to-face meetings were also organized. Evaluation results of the three cases clearly show that active, collaborative learning at a distance is possible. Blended learning enables the use of novel instructional methods and student-centred education. The three cases employ different educational methods, thus illustrating diverse possibilities and a variety of learning activities in blended learning. Interaction and communication rules, the role of the teacher, careful selection of collaboration tools and technical preparation should be considered when designing and implementing blended learning.
Decreased IL‐10 expression in stefin B‐deficient macrophages is regulated by the MAP kinase and STAT‐3 signaling pathways
Authors: Maher Katarina , Završnik Janja , Jerič-Kokelj Barbara , Vasiljeva Olga , Turk Boris , Kopitar-Jerala Nataša
Published: January 2014

Innate immune responses are tightly regulated to avoid excessive activation and subsequent inflammatory damage to the host, and interleukin‐10 (IL‐10) plays a crucial role in preventing inflammation. Stefin B (cystatin B) is an endogenous inhibitor of cysteine proteinases. In stefin B‐deficient bone marrow‐derived macrophages (BMDMs), we detected an increase in the induction of the LPS‐induced pro‐inflammatory signal nitric oxide (NO) but decreased IL‐10 expression. The phosphorylation of ERK and p38 MAP‐kinases was significantly decreased in stefin B‐deficient macrophages, as was STAT‐3 phosphorylation. These findings show that stefin B influences the expression of anti‐inflammatory IL‐10 in response to the TLR4 agonist LPS.
The Ca2+‐dependent interaction of calpastatin domain L with the C‐terminal tail of the Cav1.2 channel
Authors: Sun Wei , Feng Rui , Hu Huiyuan , Guo Feng , Gao Qinghua , Shao Dongxue , Yin Dandan , Wang Hongmei , Sun Xuefei , Zhao Meimi , Minobe Etsuko , Sun Yingxian , Jiao Guangyu , Kameyama Masaki , Hao Liying
Published: January 2014

To demonstrate the interaction of calpastatin (CS) domain L (CSL) with Cav1.2 channel, we investigated the binding of CSL with various C‐terminus‐derived peptides at ≈ free, 100 nM, 10 μM, and 1 mM Ca2+ by using the GST pull‐down assay method. Besides binding with the IQ motif, CSL was also found to bind with the PreIQ motif. With increasing [Ca2+], the affinity of the CSL–IQ interaction gradually decreased, and the affinity of the CSL–PreIQ binding gradually increased. The results suggest that CSL may bind with both the IQ and PreIQ motifs of the Cav1.2 channel in different Ca2+‐dependent manners.
MiR‐874 promotes intestinal barrier dysfunction through targeting AQP3 following intestinal ischemic injury
Authors: Zhi Xiaofei , Tao Jinqiu , Li Zengliang , Jiang Baofei , Feng Jin , Yang Li , Xu Hao , Xu Zekuan
Published: January 2014

Intestinal ischemic injury is a significant clinical problem arising from diseases or as a complication of abdominal surgery. Our previous study showed aquaporin 3 is involved in intestinal barrier impairment. Here, we revealed that intestinal ischemia induced a time‐dependent increase of miR‐874 expression and a time‐dependent decrease of AQP3 expression, and the level of miR‐874 expression was inversely related to AQP3 protein expression. In addition, miR‐874 promoted the paracellular permeability in vitro through targeting 3′UTR of AQP3. Two of the tight junction proteins, Occludin and Claudin‐1, were found to be involved in miR‐874‐induced intestinal barrier dysfunction.
Active Rehabilitation in a Pediatric Extracorporeal Membrane Oxygenation Patient
Authors: Zebuhr Carleen , Sinha Amit , Skillman Heather , Buckvold Shannon
Published: January 2014

Decreased intensive care unit (ICU) mortality has led to an increase in ICU morbidity. ICU‐induced immobilization plays a major role in this morbidity. Recently, ICU mobility has been shown to be safe and effective in adolescent and adult patients. We report the successful rehabilitation of an 8‐year‐old boy with severe acute respiratory distress syndrome on extracorporeal membrane oxygenation. A child who is critically ill may safely perform active rehabilitation while on venovenous extracorporeal membrane oxygenation. The gains achieved through active rehabilitation and optimal nutrition can facilitate recovery from severe acute respiratory distress syndrome in select pediatric patients on extracorporeal membrane oxygenation.
Yeast hydrolysate supplementation increases field abundance and persistence of sexually mature sterile Queensland fruit fly,Bactrocera tryoni(Froggatt)
Authors: Reynolds O.L. , Orchard B.A. , Collins S.R. , Taylor P.W.
Published: January 2014

The sterile insect technique (SIT) is a non-chemical approach used to control major pests from several insect families, including Tephritidae, and entails the mass-release of sterile insects that reduce fertility of wild populations. For SIT to succeed, released sterile males must mature and compete with wild males to mate with wild females. To reach sexual maturity, the Queensland fruit fly,Bactrocera tryoni(Froggatt) (Diptera: Tephritidae), must obtain adequate nutrition after adult emergence; however, in current SIT programs sterileB. tryonireceive a pre-release diet that lacks key nutrients required to sustain sexual development. The chief objective of this study was to determine whether pre-release yeast hydrolysate (YH) supplements affect the persistence and abundance of sexually mature sterile maleB. tryoniunder field conditions. Experiments were run in outdoor cages under conditions of low and high environmental stress that differed markedly in temperature and humidity, and in the field. Under low environmental stress conditions, survival of sterileB. tryoniwas monitored in cages under three diet treatments: (i) sugar only, (ii) sugar plus YH or (iii) sugar plus YH for 48 h and sugar only thereafter. Under high environmental stress conditions survival of sterileB. tryoniwas monitored in cages under four diet treatments: (i) white sugar only, (ii) brown sugar only, (iii) white sugar plus YH and (iv) brown sugar plus YH. In a replicated field study, we released colour-marked sterileB. tryonifrom two diet regimes, YH-supplemented or YH-deprived, and monitored abundance of sexually mature males. In the low-stress cage study, there was no effect of diet, although overall females lived longer than males. In the high stress cage study, mortality was lower for YH-fed flies than YH-deprived flies and females lived longer than males. In the field, YH supplementation resulted in higher abundance of sexually mature sterile males, with 1.2 YH-fed flies trapped for every YH-deprived fly trapped. Under field conditions, YH supplementation can increase over-flooding ratios and hence may improve the effectiveness of SIT programmes.
Age differences in achievement goals and motivational characteristics of work in an ageing workforce
Authors: HEIDEMEIER HEIKE , STAUDINGER URSULA M.
Published: January 2014

This study reviews theory and results from developmental psychology to examine age differences in workplace achievement goals. We investigated whether goal level decreases with age and, by comparing the relative strength of different goals within individuals, we examined whether dominant achievement goals are related to age. In a large sample of employees (N=747), older workers' higher affective commitment and intrinsic motivation compensated for age-related decline in the importance of achievement goals. Whether learning-approach and learning-avoidance were dominant goals was not related to age but instead to skill level, affective commitment and intrinsically satisfying work. Dominant performance-approach goals were more common among males. Performance-avoidance was most likely to be a dominant goal among older males. Moreover, with age, performance-goal orientations had increasingly maladaptive consequences for self-efficacy and affect at work.
Beyond Duverger: party ideology, party-state relations and informal finance strategies in advanced democracies
Authors: Bolleyer Nicole , Bytzek Evelyn
Published: January 2014

This article examines one widespread but widely overlooked informal party practice to access state resources indirectly: the ‘taxing’ of MP salaries, which obliges candidates who win elected office on a party ticket to regularly donate a fixed share of their private income to party coffers. Linking Duverger’s classical approach on party organization that stresses the importance of party–society relations with the more recent, highly influential cartel party theory that argues that parties are shaped by their relationship with the state, we specify factors that shape the acceptability of this informal practice and thus parties’ capacity to extract rent from their MPs. The analysis of an original dataset covering parties across a wide range of advanced democracies reveals that demanding salary transfers from national MPs to their parties are not only more common in leftist parties as argued by Duverger but also in systems in which the penetration of the state apparatus by political parties is intense as argued by the cartel party approach. Linking the two perspectives further reveals that ideological differences between parties shape their relative capacity to collect higher payments from MPs in systems where parties and the state are less intertwined.
Cross-regulation of Connexin43 and β-catenin influences differentiation of human neural progenitor cells
Authors: Rinaldi F , Hartfield E M , Crompton L A , Badger J L , Glover C P , Kelly C M , Rosser A E , Uney J B , Caldwell M A
Published: January 2014

Connexin43 (Cx43) is the most widely and abundantly expressed gap junction (GJ) protein and it is strongly associated with the regulation of cell cycle progression. Emerging roles for Cx43 in cell adhesion and migration during neural differentiation have also been recently recognized, and this has emphasized the involvement of Cx43 in different physiological process beyond its role as a GJ protein. In this study, we explore the function of Cx43 in the differentiation of human neural progenitor cells (hNPCs) using viral vectors that mediate the overexpression or knockdown of the protein. Results showed that in the absence of this protein fetal cortex-derived hNPCs differentiated toward a neuronal phenotype at expenses of a glial phenotype. Furthermore, the silencing of Cx43 did not affect hNPC proliferation rate or numbers of apoptotic cells. The increase in the number of neurons was not recapitulated when GJ intercellular communications were pharmacologically blocked, and this suggested that Cx43 was influencing hNPCs differentiation with a GJ-independent effect. In addition, Cx43 knockdown significantly increased β-catenin signaling, which has been shown to regulate the transcription of pro-neuronal genes during embryonic neural development. Our results add further support to the hypothesis that Cx43 protein itself regulates key signaling pathways during development and neurogenesis beyond its role as GJ protein.
Single-cell enabled comparative genomics of a deep ocean SAR11 bathytype
Authors: Thrash J Cameron , Temperton Ben , Swan Brandon K , Landry Zachary C , Woyke Tanja , DeLong Edward F , Stepanauskas Ramunas , Giovannoni Stephan J
Published: January 2014

Bacterioplankton of the SAR11 clade are the most abundant microorganisms in marine systems, usually representing 25% or more of the total bacterial cells in seawater worldwide. SAR11 is divided into subclades with distinct spatiotemporal distributions (ecotypes), some of which appear to be specific to deep water. Here we examine the genomic basis for deep ocean distribution of one SAR11 bathytype (depth-specific ecotype), subclade Ic. Four single-cell Ic genomes, with estimated completeness of 55%–86%, were isolated from 770 m at station ALOHA and compared with eight SAR11 surface genomes and metagenomic datasets. Subclade Ic genomes dominated metagenomic fragment recruitment below the euphotic zone. They had similar COG distributions, high local synteny and shared a large number (69%) of orthologous clusters with SAR11 surface genomes, yet were distinct at the 16S rRNA gene and amino-acid level, and formed a separate, monophyletic group in phylogenetic trees. Subclade Ic genomes were enriched in genes associated with membrane/cell wall/envelope biosynthesis and showed evidence of unique phage defenses. The majority of subclade Ic-specfic genes were hypothetical, and some were highly abundant in deep ocean metagenomic data, potentially masking mechanisms for niche differentiation. However, the evidence suggests these organisms have a similar metabolism to their surface counterparts, and that subclade Ic adaptations to the deep ocean do not involve large variations in gene content, but rather more subtle differences previously observed deep ocean genomic data, like preferential amino-acid substitutions, larger coding regions among SAR11 clade orthologs, larger intergenic regions and larger estimated average genome size.
The quest for a unified view of bacterial land colonization
Authors: Wu Hao , Fang Yongjun , Yu Jun , Zhang Zhang
Published: January 2014

Exploring molecular mechanisms underlying bacterial water-to-land transition represents a critical start toward a better understanding of the functioning and stability of the terrestrial ecosystems. Here, we perform comprehensive analyses based on a large variety of bacteria by integrating taxonomic, phylogenetic and metagenomic data, in the quest for a unified view that elucidates genomic, evolutionary and ecological dynamics of the marine progenitors in adapting to nonaquatic environments. We hypothesize that bacterial land colonization is dominated by a single-gene sweep, that is, the emergence of dnaE2 derived from an early duplication event of the primordial dnaE, followed by a series of niche-specific genomic adaptations, including GC content increase, intensive horizontal gene transfer and constant genome expansion. In addition, early bacterial radiation may be stimulated by an explosion of land-borne hosts (for example, plants and animals) after initial land colonization events.
Evolutionary analysis of a streamlined lineage of surface ocean Roseobacters
Authors: Luo Haiwei , Swan Brandon K , Stepanauskas Ramunas , Hughes Austin L , Moran Mary Ann
Published: January 2014

The vast majority of surface ocean bacteria are uncultivated. Compared with their cultured relatives, they frequently exhibit a streamlined genome, reduced G+C content and distinct gene repertoire. These genomic traits are relevant to environmental adaptation, and have generally been thought to become fixed in marine bacterial populations through selection. Using single-cell genomics, we sequenced four uncultivated cells affiliated with the ecologically relevant Roseobacter clade and used a composition-heterogeneous Bayesian phylogenomic model to resolve these single-cell genomes into a new clade. This lineage has no representatives in culture, yet accounts for ∼35% of Roseobacters in some surface ocean waters. Analyses of multiple genomic traits, including genome size, G+C content and percentage of noncoding DNA, suggest that these single cells are representative of oceanic Roseobacters but divergent from isolates. Population genetic analyses showed that substitution of physicochemically dissimilar amino acids and replacement of G+C-rich to G+C-poor codons are accelerated in the uncultivated clade, processes that are explained equally well by genetic drift as by the more frequently invoked explanation of natural selection. The relative importance of drift vs selection in this clade, and perhaps in other marine bacterial clades with streamlined G+C-poor genomes, remains unresolved until more evidence is accumulated.
Lateral transfer of eukaryotic ribosomal RNA genes: an emerging concern for molecular ecology of microbial eukaryotes
Authors: Yabuki Akinori , Toyofuku Takashi , Takishita Kiyotaka
Published: January 2014

Ribosomal RNA (rRNA) genes are widely utilized in depicting organismal diversity and distribution in a wide range of environments. Although a few cases of lateral transfer of rRNA genes between closely related prokaryotes have been reported, it remains to be reported from eukaryotes. Here, we report the first case of lateral transfer of eukaryotic rRNA genes. Two distinct sequences of the 18S rRNA gene were detected from a clonal culture of the stramenopile, Ciliophrys infusionum. One was clearly derived from Ciliophrys, but the other gene originated from a perkinsid alveolate. Genome-walking analyses revealed that this alveolate-type rRNA gene is immediately adjacent to two protein-coding genes (ubc12 and usp39), and the origin of both genes was shown to be a stramenopile (that is, Ciliophrys) in our phylogenetic analyses. These findings indicate that the alveolate-type rRNA gene is encoded on the Ciliophrys genome and that eukaryotic rRNA genes can be transferred laterally.
Rapid recovery of soil bacterial communities after wildfire in a Chinese boreal forest
Authors: Xiang Xingjia , Shi Yu , Yang Jian , Kong Jianjian , Lin Xiangui , Zhang Huayong , Zeng Jun , Chu Haiyan
Published: January 2014

Fires affect hundreds of millions of hectares annually. Above-ground community composition and diversity after fire have been studied extensively, but effects of fire on soil bacterial communities remain largely unexamined despite the central role of bacteria in ecosystem recovery and functioning. We investigated responses of bacterial community to forest fire in the Greater Khingan Mountains, China, using tagged pyrosequencing. Fire altered soil bacterial community composition substantially and high-intensity fire significantly decreased bacterial diversity 1-year-after-burn site. Bacterial community composition and diversity returned to similar levels as observed in controls (no fire) after 11 years. The understory vegetation community typically takes 20–100 years to reach pre-fire states in boreal forest, so our results suggest that soil bacteria could recover much faster than plant communities. Finally, soil bacterial community composition significantly co-varied with soil pH, moisture content, NH4+ content and carbon/nitrogen ratio (P < 0.05 in all cases) in wildfire-perturbed soils, suggesting that fire could indirectly affect bacterial communities by altering soil edaphic properties.
Engineering Topological Surface States and Giant Rashba Spin Splitting in BiTeI/Bi2Te3 Heterostructures
Authors: Zhou Jin-Jian , Feng Wanxiang , Zhang Ying , Yang Shengyuan A. , Yao Yugui
Published: January 2014

The search for strongly inversion asymmetric topological insulators is an active research field because these materials possess distinct properties compared with the inversion symmetric ones. In particular, it is desirable to realize a large Rashba spin-splitting (RSS) in such materials, which combined with the topological surface states (TSS) could lead to useful spintronics applications. In this report, based on first principles calculations, we predict that the heterostructure of BiTeI/Bi2Te3 is a strong topological insulator with a giant RSS. The coexistence of TSS and RSS in the current system is native and stable. More importantly, we find that both the "Equation missing" invariants and the Rashba energy can be controlled by engineering the layer geometries of the heterostructure and the Rashba energy can be made even larger than that of bulk BiTeI. Our work opens a new route for designing topological spintronics devices based on inversion asymmetric heterostructures.
First-principles Thermodynamic Models in Heterogeneous Catalysis
Authors: Bray J. M. , Schneider W. F.
Published: January 2014

In this chapter we describe and demonstrate computational approaches to modeling surface adsorption, a process fundamental to all heterogeneous catalysts that takes into account surface structure, adsorbate–adsorbate interactions, and reaction conditions. We begin by describing the development of supercell density functional theory (DFT) models of adsorption at a surface, taking as an example O adsorption at the stepped and kinked Pt(321) surface. We then discuss how these DFT simulations can be used as a basis to parameterize a cluster expansion (CE) model, an Ising-type Hamiltonian that accounts for structural heterogeneity and for adsorbate–adsorbate interactions on a lattice. When converged, the DFT and CE models provide a self-consistent description of the ground states of the surface–adsorbate system. We present a detailed thermodynamic analysis of the system and describe how this can be used to extract equilibrium surface properties from the converged database and provide access to coverage-dependent adsorption energies and surface phase diagrams. Further, the CE enables Monte Carlo simulations of more extended surfaces under fixed temperature and chemical potential conditions, and the average properties from these simulations provide access to average coverages, heat capacities, and phase behavior. Finally, we describe how these same tools can be applied further to relate surface properties with reaction conditions and to describe surface kinetic processes such as diffusion or adsorption.
A Reaxff Reactive Force-field for Proton Transfer Reactions in Bulk Water and its Applications to Heterogeneous Catalysis
Authors: van Duin Adri C. T. , Zou Chenyu , Joshi Kaushik , Bryantsev Vyascheslav , Goddard William A.
Published: January 2014

We have developed a ReaxFF reactive force-field description for bulk water and for proton transfer in the aqueous phase. This ReaxFF potential was parameterized exclusively against quantumchemical (QM) data, describing a broad range of intra- and intermolecular water interactions, including H–H, HO–OH and O=O bond dissociation energies, charge distributions, angle bending energies, binding energies for [H2O]2–35-clusters, H-transfer reactions pathways in H3O+/H2O, [H2O]n and HO−/H2O-clusters and ice densities and cohesive energies. We find good agreement between ReaxFF and QM for all these cases. We found that this QM-based ReaxFF potential gives a good description of bulk water phases and proton migration, reproducing experimental density, radial distribution and diffusion data, while it overestimates proton diffusion in the OH−/water system. We anticipate that this ReaxFF water description, in combination with ongoing ReaxFF-work on amines, carboxylic acids, phosphates and inorganic materials, should be highly suitable for simulating biochemical reactions involving enzymes and DNA. Furthermore, this potential can be used to simulate water reactions and proton diffusion on metal and metal oxide surfaces, opening up applications to catalysis, crystal growth and crack propagation studies. We have provided a specific example of this force field to heterogeneous catalysis, showing an oxygen/hydrogen recombination reaction in an iron nanoparticle.
Charge Transfer Potentials
Authors: Cheng Yu-Ting , Liang Tao , Phillpot Simon R. , Sinnott Susan B.
Published: January 2014

This chapter reviews the developments that have enabled the employment of many-body, reactive variable charge potentials in atomic-scale simulations. In particular, the formalisms for the charge optimized many-body, or COMB, potentials are presented and their application to chemistry in classical molecular dynamics reactions is reported. The specific reactions that are considered include ethyl radicals on copper surfaces and carbon dioxide combined with water on copper clusters supported on zinc oxide surfaces. The role of charge transfer in these processes, and in the relative energies of copper clusters on zinc oxide surfaces is discussed.
Effect of TiO2crystal structure on the catalytic performance of Co3O4/TiO2catalyst for low-temperature CO oxidation
Authors: Li Jie , Lu Guanzhong , Wu Guisheng , Mao Dongsen , Guo Yanglong , Wang Yanqin , Guo Yun
Published: January 2014

Co3O4supported on TiO2(anatase (A), rutile (R) and P25 (Degussa)) catalysts were prepared by a deposition–precipitation method. Co3O4/TiO2(A) shows excellent activity for CO oxidation with 100% conversion at −43 °C.
Structure and hydrogen bonding of the hydrated selenite and selenate ions in aqueous solution
Authors: Eklund Lars , Persson Ingmar
Published: January 2014

The selenite ion has an asymmetric hydration sphere with loosely electrostatically bound water molecules outside the free electron pair.
Combining oxime-based [Mn6] clusters with cyanometalates: 1D chains of [Mn6] SMMs from [M(CN)2]− (M = Au, Ag)
Authors: Sanz Sergio , Frost Jamie M. , Lorusso Giulia , Evangelisti Marco , Pitak Mateusz B. , Coles Simon J. , Nichol Gary S. , Brechin Euan K.
Published: January 2014

The linear [M(CN)2]− (M = Au, Ag) anions can be used as metalloligands in oxime-based Mn chemistry to afford 1D chains of [MnIII6] single-molecule magnets (SMMs).
Evidence for dissolved organic matter as the primary source and sink of photochemically produced hydroxyl radical in arctic surface waters
Authors: Page Sarah E. , Logan J. Robert , Cory Rose M. , McNeill Kristopher
Published: January 2014

Photochemical hydroxyl radical formation decreases with increasing water residence time in a system of lakes connected by streams in the Arctic.
Mild gold-catalyzed three-component dehydrogenative coupling of terminal alkynes to amines and indole-2-carboxaldehyde
Authors: Li Jian , Wang Hongni , Sun Jiangtao , Yang Yang , Liu Li
Published: January 2014

A mild gold-catalyzed three-component dehydrogenative coupling of terminal alkynes to amines and indole-2-carboxaldehyde has been developed, which provides a practical synthetic strategy for the synthesis of indole derivatives.
Simulation and optimization of a horizontal ammonia synthesis reactor using genetic algorithm
Authors: Azarhoosh M. J. , Farivar F. , Ale Ebrahim H.
Published: January 2014

A new method (improved shooting method) is used for effectiveness factor calculation by the diffusion-reaction approach.
Cellulose generated-microporous carbon nanosheets with nitrogen doping
Authors: Shen Wenzhong , Hu Tuoping , Fan Weibin
Published: January 2014

Nanosheet porous carbon with high surface area and pore volume, unique compositional and structural features endow the nitrogen-doped porous carbon nanosheets with superior CO2 adsorption performance.
Chemical communication between liposomes encapsulating a chemical oscillatory reaction
Authors: Tomasi Raphaël , Noël Jean-Marc , Zenati Aymen , Ristori Sandra , Rossi Federico , Cabuil Valérie , Kanoufi Frédéric , Abou-Hassan Ali
Published: January 2014

Electrochemical measurements and numerical simulations are employed to understand the chemical communication between liposomes prepared in microfluidics and encapsulating a chemical oscillator.
Fluorescent sensing of99Tc pertechnetate in water
Authors: Amendola Valeria , Bergamaschi Greta , Boiocchi Massimo , Alberto Roger , Braband Henrik
Published: January 2014

The fluorescent cage senses pertechnetate in water at μM concentration, opening perspectives to detect the pollutant without radioanalytical instrumentation.
Pulsatile drug release from electrospun poly(ethylene oxide)–sodium alginate blend nanofibres
Authors: Kaassis Abdessamad Y. A. , Young Neil , Sano Naoko , Merchant Hamid A. , Yu Deng-Guang , Chatterton Nicholas P. , Williams Gareth R.
Published: January 2014

Novel and highly tuneable pulsatile drug release systems have been prepared by electrospinning.