bluuebunny/crossref_metadata_2025 huggingface dataset:
Short Communication: Aspen forest overstory relations to understory production
Authors: LaRade Shawna , Bork Edward
Published: August 2011

LaRade, S. E. and Bork, E. W. 2011. Short Communication: Aspen forest overstory relations to understory production. Can. J. Plant Sci. 91: 847–851. We examined the relationship between aspen cover and understory production across two topographic positions and two management systems within the Aspen Parkland of eastern Alberta. Understory biomass typically declined with increasing overstory, with greater yield losses on north-facing forests than bottomlands. Browse often compensated for herbage loss, and limited evidence of facilitative growth was observed.
Estimating fusion properties for functionalised acids
Authors: Compernolle S. , Ceulemans K. , Müller J.-F.
Published: August 2011

Abstract. Multicomponent organic aerosol (OA) is likely to be liquid, or partially liquid. Hence, to describe the partitioning of these components, their liquid vapour pressure is desired. Functionalised acids (e.g. diacids) can be a significant part of OA. But often measurements are available only for solid state vapour pressure, which can differ by orders of magnitude from their liquid counterparts. To convert such a sublimation pressure to a subcooled liquid vapour pressure, fusion properties (two out of these three quantities: fusion enthalpy, fusion entropy, fusion temperature) are required. Unfortunately, experimental knowledge of fusion properties is sometimes missing in part or completely, hence an estimation method is required. Several fusion data estimation methods are tested here against experimental data of functionalised acids, and a simple estimation method is developed, specifically for this family of compounds, with a significantly smaller estimation error than the literature methods.
Study of frequency pattern of coherent turbulent flow over ripples using image processing with implication in river restoration
Authors: Keshavarzi A. , Ball J. , Nabavi H.
Published: August 2011

Abstract. River channel change and bed scourings are source of major environmental problem for fish and aquatic habitat. The bed form such as ripples and dunes is the result of an interaction between turbulent flow structure and sediment particles at the bed. The structure of turbulent flow over ripples is important to understand initiation of sediment entrainment and its transport. The focus of this study is the measurement and analysis of the dominant bursting events and the flow structure over ripples in the bed of a channel. Two types of ripples with sinusoidal and triangular forms were tested in this study. The velocities of flow over the ripples were measured in three dimensions using an Acoustic Doppler Velocimeter with a sampling rate of 50 Hz. These velocities were measured at different points within the flow depth from the bed and at different longitudinal positions along the flume. A CCD camera was used to capture 1500 sequential images from the bed and to monitor sediment movement at different positions along the bed. Application of image processing technique enabled us to compute the number of entrained and deposited particles over the ripples. From a quadrant decomposition of instantaneous velocity fluctuations close to the bed, it was found that bursting events downstream of the second ripple, in Quadrants 1 and 3, were dominant whereas upstream of the ripple, Quadrants 2 and 4 were dominant. More importantly consideration of these results indicates that the normalized occurrence probabilities of sweep events are in phase with the bed forms whereas those of ejection event are out of phase with the bed form. Therefore entrainment would be expected to occur upstream and deposition occurs downstream of the ripple. These expectations were confirmed by measurement of entrained and deposited sediment particles from the bed. These above information can be used in practical application for rivers where restoration is required.
Variability of snow depth at the plot scale: implications for mean depth estimation and sampling strategies
Authors: López-Moreno J. I. , Fassnacht S. R. , Beguería S. , Latron J. B. P.
Published: August 2011

Abstract. Snow depth variability over small distances can affect the representativeness of depth samples taken at the local scale, which are often used to assess the spatial distribution of snow at regional and basin scales. To assess spatial variability at the plot scale, intensive snow depth sampling was conducted during January and April 2009 in 15 plots in the Rio Ésera Valley, central Spanish Pyrenees Mountains. Each plot (10 × 10 m; 100 m2) was subdivided into a grid of 1 m2 squares; sampling at the corners of each square yielded a set of 121 data points that provided an accurate measure of snow depth in the plot (considered as ground truth). The spatial variability of snow depth was then assessed using sampling locations randomly selected within each plot. The plots were highly variable, with coefficients of variation up to 0.25. This indicates that to improve the representativeness of snow depth sampling in a given plot the snow depth measurements should be increased in number and averaged when spatial heterogeneity is substantial. Snow depth distributions were simulated at the same plot scale under varying levels of standard deviation and spatial autocorrelation, to enable the effect of each factor on snowpack representativeness to be established. The results showed that the snow depth estimation error increased markedly as the standard deviation increased. The results indicated that in general at least five snow depth measurements should be taken in each plot to ensure that the estimation error is <10 %; this applied even under highly heterogeneous conditions. In terms of the spatial configuration of the measurements, the sampling strategy did not impact on the snow depth estimate under lack of spatial autocorrelation. However, with a high spatial autocorrelation a smaller error was obtained when the distance between measurements was greater.
Sophists and Sophistry in the Wealth of Nations
Authors: Gore David Charles
Published: August 2011

The Stoic is often seen as the forerunner of Adam Smith's market man of morals, but others have suggested that the sophist played a role in the formation of market morality and political economy. This article traces Smith's treatment of ancient sophists and his use of the term sophistry in the Wealth of Nations. Smith praised ancient sophists for their effective didactic oratory and their ability to make money through teaching. Smith criticized arguments as sophistic when they promoted monetary advantage for a few over and above the principle of competition. This varied reception of sophists and sophistry suggests a keen understanding of the rhetorical tradition and its capacity to influence the development of the discourse of political economy. Smith's use of sophistry and reference to the sophists invites a deeper awareness of the essential vitality of effective argumentation for Smith's “system of natural liberty.”
John Dewey and the Question of Artful Criticism
Authors: Stroud Scott R.
Published: August 2011

John Dewey's work on aesthetics, community, and art holds many untapped resources for the study and melioration of communicative practices. This article explores Dewey's distinctive and pluralistic idea of criticism and argues that such a notion can be used to elaborate pragmatist rhetoric. To lend contrast to this endeavor, I develop the concept of the “implied critic,” and compare the sort of critic assumed by Deweyan pragmatism to the critic implied by Raymie McKerrow's critical rhetoric. What a pragmatist approach to rhetorical criticism entails will be detailed by examining the variety of purposes that can be pursued by an individual in reflecting on rhetorical artifacts. Such a pragmatist rhetoric explains the notion of artful criticism that Dewey features so prominently in his analysis of ideal forms of community.
Creative Metaphors, Synchronicity, and Quantum Physics
Authors: Frentz Thomas
Published: August 2011

In this work, I argue that creative metaphors are formed when some persistent problem, caused by an inadequacy in preexisting knowledge, descends into the collective unconscious, is reconfigured unconsciously in novel ways, and then reemerges back into consciousness where the impasse is resolved by the metaphorical expression of new knowledge. To develop this position, I (1) review and critique some well-known language-based studies of metaphor, (2) summarize psychoanalytic and depth psychological approaches to the psyche as one way to overcome the shortcomings of the language-based scholarship, (3) relate C. G. Jung's account of the psyche and his related notion of synchronicity to creative metaphors, (4) graft a quantum physics approach to material reality back onto Jung's work as a provisional structure of the collective unconscious, and finally, (5) offer some suggestions about how creative metaphors might work psychologically.
Mgat5 Deficiency in T Cells and Experimental Autoimmune Encephalomyelitis
Authors: Grigorian Ani , Demetriou Michael
Published: August 2011

Multiple sclerosis (MS) is an inflammatory demyelinating and neurodegenerative disease initiated by autoreactive T cells. Mgat5, a gene in the Asn (N-) linked protein glycosylation pathway, associates with MS severity and negatively regulates experimental autoimmune encephalomyelitis (EAE) and spontaneous inflammatory demyelination in mice. N-glycan branching by Mgat5 regulates interaction of surface glycoproteins with galectins, forming a molecular lattice that differentially controls the concentration of surface glycoproteins. T-cell receptor signaling, T-cell proliferation, TH1 differentiation, and CTLA-4 endocytosis are inhibited by Mgat5 branching. Non-T cells also contribute to MS pathogenesis and express abundant Mgat5 branched N-glycans. Here we explore whether Mgat5 deficiency in myelin-reactive T cells is sufficient to promote demyelinating disease. Adoptive transfer of myelin-reactive Mgat5−/− T cells into Mgat5+/+ versus Mgat5−/− recipients revealed more severe EAE in the latter, suggesting that Mgat5 branching deficiency in recipient naive T cells and/or non-T cells contribute to disease pathogenesis.
Robust IPTV Delivery with Adaptive Rateless Coding over a Mobile WiMAX Channel
Authors: Al-Jobouri Laith , Fleury Martin , Ghanbari Mohammad
Published: August 2011

As intelligent content management of IPTV moves popular material nearer to the end-user, application-layer channel coding schemes, involving the retransmission of extra redundant data, become attractive as a result of the reduced latency. Application-layer, adaptive rateless channel coding is exploited in this paper's scheme to reconstruct streamed video across an IEEE 802.16e (mobile WiMAX) channel. The paper concentrates on the trade-offs in implementing the scheme, showing that exact calculation of the redundant data has the potential to reduce the forward error correction bit-rate overhead. To reduce delay, an appropriate compression rate should also be selected.
On Irreducible Linear Groups of Nonprimary Degree
Authors: Yadchenko A. A.
Published: August 2011

It is established that degree 2|A|+1 of irreducible complex linear
group with the group A of cosimple automorphisms of odd order is a prime number
and proved that if degree 2|H|+1 of π-solvable irreducible complex linear group G with a π-Hall TI-subgroup H is not a prime power, then H is Abelian and normal
in G.
Stereolithography‐Based Hydrogel Microenvironments to Examine Cellular Interactions
Authors: Zorlutuna Pinar , Jeong Jae Hyun , Kong Hyunjoon , Bashir Rashid
Published: August 2011

A spatially organized three‐dimensional (3D) co‐culture of multiple cell types is required to recapitulate cellular interactions and microenvironments in complex tissues. Although there are limited reports for 3D patterning of cells and materials, approaches to examine functional interactions of 3D spatially patterned multiple cell types are lacking entirely. This is mostly due to difficulties in controlling the physical arrangement of cells in a 3D matrix and the physical properties of the cell‐encapsulating matrix, while keeping the cells alive and functional for extended periods of time. In this study, an automated maskless fabrication technique is combined with a tunable polymer blend to spatially organize primary hippocampus neurons (HNs) and skeletal muscle myoblast cells (MCs) in a 3D hydrogel matrix with tunable mechanical and degradation properties. The spatial organization of these multiple cell types revealed that the presence of MCs resulted in increased cholinergic functionality of the HNs, as quantified by their choline acetyltransferase activity. The presence of a factor alone is not sufficient, but its spatiotemporal control is necessary; a condition that is possibly true for many cellular interactions. Therefore, the system described here offers a different approach to examine such previously unknown interactions. The approach proposed in this study can be used to examine interactions between many different cell types and shift the 3D fabrication paradigm to a next level, which is to fabricate tissues that are not only viable but also functional.
Current‐Induced Restructuring and Chemical Modification of N‐Doped Multi‐walled Carbon Nanotubes
Authors: Aslam Zabeada , Nicholls Rebecca , Koós Antal , Nicolosi Valeria , Grobert Nicole
Published: August 2011

Multi‐walled carbon nanotubes (MWCNTs) have long been anticipated as candidates for electrical components in an increasingly miniaturized electronics industry due to their inherent electrical properties. It is possible to manipulate and control these properties by introducing dopants such as N, B, and P. Although some current‐induced structural changes in MWCNTs have been observed, no systematic study has been carried out to explore the correlation of changes in the internal structure with the electronic behavior of doped‐MWCNTs in terms of the current densities present. In situ transmission electron microscopy (TEM) investigations are presented here of individual, N‐doped MWNCT (N‐MWCNTs) using the in situ TEM/scanning tunneling microscopy (TEM/STM) Nanofactory© holder. It is observed for the first time that N‐MWCNTs not only undergo current‐induced structural transformation; i.e., from the typical bamboo structure of N‐MWCNTs to the stacked cones, but also—and most importantly—the complete removal of the dopant causes a significant change in the electronic behavior. This has serious implications for the use of doped CNTs as electronic components, especially since tremendous efforts are being made to synthesize CNTs with controlled dopant concentrations.
The evolving spectrum of pulmonary disease in responders to the World Trade Center tragedy
Authors: Guidotti Tee L. , Prezant David , de la Hoz Rafael E. , Miller Albert
Published: August 2011

On September 11, 2001, events at the World Trade Center (WTC) exposed residents of New York City to WTC dust and products of combustion and pyrolysis. The majority of WTC‐exposed fire department rescue workers experienced a substantial decline in airflow over the first 12 months post‐9/11, in addition to the normal age‐related decline that affected all responders, followed by a persistent plateau in pulmonary function in the 6 years thereafter. The spectrum of the resulting pulmonary diseases consists of chronic inflammation, characterized by airflow obstruction, and expressing itself in different ways in large and small airways. These conditions include irritant induced asthma, non‐specific chronic bronchitis, aggravated pre‐existing obstructive lung disease (asthma or COPD), and bronchiolitis. Conditions concomitant with airways obstruction, particularly chronic rhinosinusitis and upper airway disease, and gastroesophageal reflux, have been prominent in this population. Less common have been reports of sarcoidosis or interstitial pulmonary fibrosis. Pulmonary fibrosis and bronchiolitis are generally characterized by long latency, relatively slow progression, and a silent period with respect to pulmonary function during its evolution. For these reasons, the incidence of these outcomes may be underestimated and may increase over time. The spectrum of chronic obstructive airways disease is broad in this population and may importantly include involvement at the bronchiolar level, manifested as small airways disease. Protocols that go beyond conventional screening pulmonary function testing and imaging may be necessary to identify these diseases in order to understand the underlying pathologic processes so that treatment can be most effective. Am. J. Ind. Med. 54:649–660, 2011. © 2011 Wiley‐Liss, Inc.
World Trade Center disaster: assessment of responder occupations, work locations, and job tasks
Authors: Woskie Susan R. , Kim Hyun , Freund Alice , Stevenson Lori , Park Bo Y. , Baron Sherry , Herbert Robin , de Hernández Micki Siegel , Teitelbaum Susan , de la Hoz Rafael E. , Wisnivesky Juan P. , Landrigan Phillip
Published: August 2011

Background

To date there have been no comprehensive reports of the work performed by 9/11 World Trade Center responders.

Methods

18,969 responders enrolled in the WTC Medical Monitoring and Treatment Program were used to describe workers' pre‐9/11 occupations, WTC work activities and locations from September 11, 2001 to June 2002.

Results

The most common pre‐9/11 occupation was protective services (47%); other common occupations included construction, telecommunications, transportation, and support services workers. 14% served as volunteers. Almost one‐half began work on 9/11 and >80% reported working on or adjacent to the “pile” at Ground Zero. Initially, the most common activity was search and rescue but subsequently, the activities of most responders related to their pre‐9/11 occupations. Other major activities included security; personnel support; buildings and grounds cleaning; and telecommunications repair.

Conclusions

The spatial, temporal, occupational, and task‐related taxonomy reported here will aid the development of a job‐exposure matrix, assist in assessment of disease risk, and improve planning and training for responders in future urban disasters. Am. J. Ind. Med. 54:681–695, 2011. © 2011 Wiley‐Liss, Inc.
Olesoxime accelerates myelination and promotes repair in models of demyelination
Authors: Magalon Karine , Zimmer Celine , Cayre Myriam , Khaldi Joseph , Bourbon Clarisse , Robles Isabelle , Tardif Gwenaëlle , Viola Angèle , Pruss Rebecca M. , Bordet Thierry , Durbec Pascale
Published: August 2011

Objective:

Multiple sclerosis is a neurodegenerative disease characterized by episodes of immune attack of oligodendrocytes leading to demyelination and progressive functional deficit. One therapeutic strategy to address disease progression could consist in stimulating the spontaneous regenerative process observed in some patients. Myelin regeneration requires endogenous oligodendrocyte progenitor migration and activation of the myelination program at the lesion site. In this study, we have tested the ability of olesoxime, a neuroprotective and neuroregenerative agent, to promote remyelination in the rodent central nervous system in vivo.

Methods:

The effect of olesoxime on oligodendrocyte progenitor cell (OPC) differentiation and myelin synthesis was tested directly in organotypic slice cultures and OPC–neuron cocultures. Using naive animals and different mouse models of demyelination, we morphologically and functionally assessed the effect of the compound on myelination in vivo.

Results:

Olesoxime accelerated oligodendrocyte maturation and enhanced myelination in vitro and in vivo in naive animals during development and also in the adult brain without affecting oligodendrocyte survival or proliferation. In mouse models of demyelination and remyelination, olesoxime favored the repair process, promoting myelin formation with consequent functional improvement.

Interpretation:

Our observations support the strategy of promoting oligodendrocyte maturation and myelin synthesis to enhance myelin repair and functional recovery. We also provide proof of concept that olesoxime could be useful for the treatment of demyelinating diseases. ANN NEUROL 2012;71:213–226
Amyloid‐beta plaque growth in cognitively normal adults: Longitudinal [11C]Pittsburgh compound B data
Authors: Vlassenko Andrei G. , Mintun Mark A. , Xiong Chengjie , Sheline Yvette I. , Goate Alison M. , Benzinger Tammie L. S. , Morris John C.
Published: August 2011

Amyloid‐beta (Aβ) accumulation was evaluated with 2 [11C]Pittsburgh compound B (PiB) positron emission tomography scans about 2.5 years apart in 146 cognitively normal adults. Seventeen of 21 participants with initially elevated Aβ deposition demonstrated subsequent Aβ plaque growth (approximately 8.0% per year), and none reverted to a state of no Aβ deposits. Ten individuals converted from negative to positive PiB status, based on a threshold of the mean cortical binding potential, representing a conversion rate of 3.1% per year. Individuals with an ε4 allele of apolipoprotein E demonstrated increased incidence of conversion (7.0% per year). Our findings suggest that the major growth in Aβ burden occurs during a preclinical stage of Alzheimer disease (AD), prior to the onset of AD‐related symptoms. Ann Neurol 2011
Distinct hyperexcitability mechanisms underlie fast ripples and epileptic spikes
Authors: Demont‐Guignard Sophie , Benquet Pascal , Gerber Urs , Biraben Arnaud , Martin Benoit , Wendling Fabrice
Published: August 2011

Objective:

In partial epilepsies, interictal epileptic spikes (IESs) and fast ripples (FRs) represent clinically relevant biomarkers characteristic of epileptogenic networks. However, their specific significance and the pathophysiological changes leading to either FRs or IESs remain elusive. The objective of this study was to analyze the conditions in which hyperexcitable networks can generate either IESs or FRs and to reveal shared or distinct mechanisms that underlie both types of events.

Methods:

This study is the first to comparatively analyze mechanisms that induce either IESs or FRs using an approach that combines computational modeling and experimental data (in vivo and in vitro). A detailed CA1 hippocampal network model is introduced. A parameter sensitivity analysis was conducted to determine which model parameters (cell related and network related) allow the most accurate simulation of FRs and IESs.

Results:

Our model indicates that although FRs and IESs share certain common mechanisms (shifted gamma‐aminobutyric acid [GABA]A reversal potential, altered synaptic transmission), there are also critical differences in terms of number of pyramidal cells involved (small vs large), spatial distribution of hyperexcitable pyramidal cells (clustered vs uniform), and firing patterns (weakly vs highly synchronized). In vitro experiments verified that subtle changes in GABAergic and glutamatergic transmission favor either FRs or IESs, as predicted by the model.

Interpretation:

This study provides insights into the interpretation of 2 interictal markers observed in intracerebral electroencephalographic data. Depending on the degree and spatiotemporal features of hyperexcitability, not only IESs or FRs are generated but also transitions between both types of events. ANN NEUROL 2012;
Recent advance on constitutive models of thermal‐sensitive shape memory polymers
Authors: Zhang Qiang , Yang Qing‐Sheng
Published: August 2011

Shape memory polymers (SMPs) are a novel class of shape memory materials which can store a deformed (temporary) shape and recover an original (permanent) shape under a shape memory thermomechanical loading–unloading cycle. The deformation mechanisms of SMPs are very complicated, but the SMPs also have a lot of advantages and the widespread application value and prospect. So developing proper constitutive models that describe thermomechanical properties of SMPs and the shape memory effect is very challenging and of great theoretical and application value. Based on the deformation mechanisms and considerable experimental investigations of SMPs, researchers have developed many constitutive models. This article investigates the deformation mechanism and introduces the recent research advance of the constitutive models of thermal‐sensitive SMPs. Special emphases are given on the micromechanical constitutive relations in which the deformation is considered being based on the microstructure of the SMPs. Finally, the lack of research and prospects for further research are discussed. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Wheat gluten fractions as wood adhesives—glutenins versus gliadins
Authors: Nordqvist Petra , Thedjil Dalia , Khosravi Sara , Lawther Mark , Malmström Eva , Khabbaz Farideh
Published: August 2011

Plant proteins, such as wheat gluten, constitute attractive raw materials for sustainable wood adhesives. In this study, alkaline water dispersions of the protein classes of wheat gluten, glutenin, and gliadin were used as adhesives to bond together wood substrates of beech. The aim of the study is to measure the tensile shear strength of the wood substrates to compare the adhesive performance of glutenin and gliadin and to investigate the influence of application method and penetration of the dispersions into the wood material. A sodium hydroxide solution (0.1M) was used as dispersing and denaturing agent. Dispersions with different protein concentrations and viscosities were used, employing wheat gluten dispersions as references. Two different application methods, a press temperature of 110°C and a press time of 15 min, were employed. The tensile shear strength and water resistance of the wood substrates were compared, using a slightly modified version of the European Standard EN 204. The bond lines of the substrates were examined by optical microscopy to study the penetration and bond‐line thickness. The results reveal that the adhesive properties of gliadin are inferior to that of both glutenin and wheat gluten, especially in terms of water resistance. However, the tensile shear strength and the water resistance of gliadin are significantly improved when over‐penetration of the protein into the wood material is avoided, rendering the adhesive performance of gliadin equal to that of glutenin and wheat gluten. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Redox initiated free radical polymerization of 4‐methylstyrene
Authors: Mortamet Anne‐Cecile , Pethrick Richard A.
Published: August 2011

Studies of the thermally initiated polymerization of 4‐methylstyrene using alkylperoxide in conjunction with cobalt and tertiary amine catalysts are reported. Addition of cobalt salts leads to a facile low temperature initiation of the polymerization process. The polymerization process was investigated using differential scanning calorimetry [DSC] and vibrating probe rheological measurements. Color changes which occur when the cobalt complex and peroxide are combined were studied using UV‐visible spectroscopy. The kinetics of polymerization was investigated using two different cobalt complexes. The initiation step in the polymerization is the conversion of the cobalt (II) to cobalt (III). The presence of the tertiary amine does not affect the oxidation state of the cobalt complex. The cobalt (III) complex gives a better rate of conversion than the cobalt (II) complex. The polymerization process is discussed in terms of redox reaction between the cobalt complex and the alkyperoxide. At low temperatures, the rate of conversion obeys simple Arrhenius kinetics. At higher temperatures the effects of gelation and catalysts inhibition influence the polymerization process. The polymerization process is sensitive to the level of available oxygen during the initiation step and inhibition by aldehyde is observed. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Novel acetylene‐terminated polyisoimides with excellent processability and properties comparison with corresponding polyimides
Authors: Zhou Heng , Liu Feng , Zhang Yongsheng , Fan Weifeng , Liu Jingfeng , Wang Zhen , Zhao Tong
Published: August 2011

Two novel acetylene‐terminated isoimide oligomers and their corresponding imide oligomers have been synthesized by using trifluoroacetic anhydride or acetic anhydride as dehydrating agent, respectively. Their main structure was confirmed by Fourier transform infrared spectroscopy (FTIR). The isoimide oligomers were amorphous and showed excellent solublility in many common solvents, such as acetone and tetrahydeofuran, whereas the imide oligomers cannot dissolve in them. Differential scanning calorimetry and rheometer were used to study crosslinking behavior and processability of these oligomers. The isoimide oligomers exhibited considerably wider processing window and lower viscosity compared with imide ones. As expected, the isoimide form could be converted to imide form through thermal treatment, which could be demonstrated by FTIR. After the oligomers were cured, the polyisoimides showed similar properties compared with corresponding polyimides. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Fractionalized exergy for evaluating research performance
Authors: Prathap Gangan
Published: August 2011

The approach based on “thermodynamic” considerations that can quantify research performance using an exergy term defined as X = iC, where i is the impact and C is the number of citations is now extended to cases where fractionalized counting of citations is used instead of integer counting.
Assessment of Decision‐making Competence in Preadolescence
Authors: Weller Joshua A. , Levin Irwin P. , Rose Jason P. , Bossard Elaine
Published: August 2011

Recent research using late adolescent (18–19 years) and adult samples suggests that within‐subject performance on a variety of standard, controlled laboratory tasks reflects a higher‐order positive manifold of decision‐making competence. The present paper extends this important work by testing whether preadolescent children (10‐ to 11‐year‐olds, n = 101) exhibit a similar structural pattern characterizing their decision‐making performance. Performance on “child‐friendly” versions of framing problems, decision matrices, consistency in risk perceptions, and calibration of confidence conformed to a one‐factor solution, comparable with that previously found with older populations. Further, individual differences in effortful control, a temperament dimension related to self‐regulative executive function, was significantly associated with decision‐making competence. Importantly, these measures were predictive of both positive (e.g., completing set goals) and negative behaviors (e.g., missing homework assignments). Results are discussed in terms of the existence of early stable patterns of decision making and rationality and the emergence of systematic individual difference factors in decision making. Copyright © 2011 John Wiley & Sons, Ltd.
Exosome nanotechnology: An emerging paradigm shift in drug delivery
Authors: Lakhal Samira , Wood Matthew J.A.
Published: August 2011

The demonstration that dendritic cell (DC)‐derived exosomes can be exploited for targeted RNAi delivery to the brain after systemic injection provides the first proof‐of‐concept for the potential of these naturally occurring vesicles as vehicles of drug delivery. As well as being amenable to existing in vivo targeting strategies already in use for viruses and liposomes, this novel approach offers the added advantages of in vivo safety and low immunogenicity. Fulfilment of the potential of exosome delivery methods warrants a better understanding of their biology, as well as the development of novel production, characterisation, targeting and cargo‐loading nanotechnologies. Ultimately, exosome‐mediated drug delivery promises to overcome important challenges in the field of therapeutics, such as delivery of drugs across otherwise impermeable biological barriers, such as the blood brain barrier, and using patient‐derived tissue as a source of individualised and biocompatible therapeutic drug delivery vehicles.
Effect of HER2 status on risk of recurrence in women with small, node-negative breast tumours
Authors: Tanaka K , Kawaguchi H , Nakamura Y , Taguchi K , Nishiyama K , Ohno S
Published: August 2011

Background

Adjuvant trastuzumab for small, node-negative, human epidermal growth factor receptor 2 (HER2)-positive breast cancer remains controversial. The purpose of this study was to investigate the risk of recurrence in women with pathological tumour node (pTN) T1 N0 tumours.

Methods

Patients with pT1 N0 breast cancer diagnosed at the National Kyushu Cancer Centre between 2001 and 2007 were reviewed. Patients were categorized according to HER2 status.

Results

Four hundred and fifty-four patients who had pT1 N0 tumours, and had not received adjuvant trastuzumab, were identified. The HER2-negative and -positive groups comprised 376 and 78 patients (17·2 per cent) respectively. At a median follow-up of 46·3 months, there were 18 recurrences. The 5-year relapse-free survival (RFS) rates were 97·2 and 88 per cent in the HER2-negative and -positive groups respectively (P < 0·001). Multivariable analysis identified HER2-positive tumour as an independent predictor of RFS in patients with pT1 N0 tumours (hazard ratio 6·65, 95 per cent confidence interval 2·53 to 17·49; P < 0·001).

Conclusion

Women with pT1 N0 HER2-positive breast cancer have a high risk of recurrence.
Persuasive design: Putting it to use
Authors: Whalen John
Published: August 2011

Editor's Summary

The fundamental goal of information architecture is to stimulate change in a user's behavior or attitude. By applying psychological principles to site design, information architects can lead site visitors through stages of engagement to action. Persuasion starts with likeability and an uncomplicated invitation to continue to explore with minimal commitment. The design must be aesthetically appealing and appropriate for the audience. A sense of intrigue, connection with others and the potential for enhanced self image add to the allure. Having confidence in the source, overcoming any reason not to act and having an easy path to action enable the user to take the final psychological steps toward persuasion. Groupon and LivingSocial illustrate the effectiveness of these persuasive principles, which can readily be applied to virtually any website design.
Biodiversity informatics
Authors: Heidorn P. Bryan
Published: August 2011

Editor's Summary

For millennia, information about biological diversity has been collected as a way to understand the living world. The information record has evolved from early papyrus to modern electronic collections, but challenges to information access persist, despite and partly due to a variety of digital techniques and applications. Information exchange is hampered by lack of access to previous work, inconsistent naming, changes over time and insufficient resources to create comprehensive databases supporting federated search with Darwin Core metadata. With progress in biodiversity informatics, we will see greater use of DNA barcoding and metagenomic techniques to describe species, remote sensing tools and geographic information systems to detect and describe species' locations and movements and to identify habitats and environmental conditions. Biodiversity informatics provides essential scientific knowledge to better understand global ecosystems and to inform land use and policy decisions.
Facile Hydrogenation of Ketones Catalyzed by Platinum on Carbon under Ordinary Pressures and Temperatures
Authors: Fujiwara Yuta , Iwasaki Youhei , Maegawa Tomohiro , Monguchi Yasunari , Sajiki Hironao
Published: August 2011

An efficient and practical procedure for the hydrogenation of aliphatic and aromatic ketones under mild reaction conditions is established. The method is highly effective even for the hydrogenation of sterically hindered ketones. Furthermore, the selective hydrogenation of the carbonyl group of aromatic ketones was achieved with the aromatic nuclei and the resulting secondary benzyl alcohol moiety still intact on addition of catalytic amount of pyridine.
Rational Design, Synthesis, and Spectroscopic and Photophysical Properties of a Visible‐Light‐Excitable, Ratiometric, Fluorescent Near‐Neutral pH Indicator Based on BODIPY
Authors: Boens Noël , Qin Wenwu , Baruah Mukulesh , De Borggraeve Wim M. , Filarowski Aleksander , Smisdom Nick , Ameloot Marcel , Crovetto Luis , Talavera Eva M. , Alvarez‐Pez Jose M.
Published: August 2011

A visible‐light‐excitable, ratiometric, brightly fluorescent pH indicator for measurements in the pH range 5–7 has been designed and synthesized by conjugatively linking the BODIPY fluorophore at the 3‐position to the pH‐sensitive ligand imidazole through an ethenyl bridge. The probe is available as cell membrane permeable methyl ester 8‐(4‐carbomethoxyphenyl)‐4,4‐difluoro‐3‐[2‐(1H‐imidazol‐4‐yl)ethenyl]‐1,5,7‐trimethyl‐3a,4a‐diaza‐4‐bora‐s‐indacene (I) and corresponding water‐soluble sodium carboxylate, sodium 8‐(4‐carboxylatophenyl)‐4,4‐difluoro‐3‐[2‐(1H‐imidazol‐4‐yl)ethenyl]‐1,5,7‐trimethyl‐3a,4a‐diaza‐4‐bora‐s‐indacene (II). The fluorescence quantum yield Φf of ester I is very high (0.8–1.0) in the organic solvents tested. The fluorescence lifetime (ca. 4 ns) of I in organic solvents with varying polarity/polarizability (from cyclohexane to acetonitrile) is independent of the solvent with a fluorescence rate constant kf of 2.4×108 s−1. Probe I is readily loaded in the cytosol of live cells, where its high fluorescence intensity remains nearly constant over an extended time period. Water‐soluble indicator II exhibits two acid–base equilibria in aqueous solution, characterized by pKa values of 6.0 and 12.6. The Φf value of II in aqueous solution is high: 0.6 for the cationic and anionic forms of the imidazole ligand, and 0.8 for neutral imidazole. On protonation–deprotonation in the near‐neutral pH range, UV/Vis absorption and fluorescence spectral shifts along with isosbestic and pseudo‐isoemissive points are observed. This dual‐excitation and dual‐emission pH indicator emits intense green‐yellow fluorescence at lower pH and intense orange fluorescence at higher pH. The influence of ionic strength and buffer concentration on the absorbance and steady‐state fluorescence of II has also been investigated. The apparent pKa of the near‐neutral acid–base equilibrium determined by spectrophotometric and fluorometric titration is nearly independent of the added buffer and salt concentration. In aqueous solution in the absence of buffer and in the pH range 5.20–7.45, dual exponential fluorescence decays are obtained with decay time τ1=4.3 ns for the cationic and τ2=3.3 ns for the neutral form of II. The excited‐state proton exchange of II at near‐neutral pH becomes reversible on addition of phosphate (H2PO4−/HPO42−) buffer, and a pH‐dependent change of the fluorescence decay times is induced. Global compartmental analysis of fluorescence decay traces collected as a function of pH and phosphate buffer concentration was used to recover values of the deactivation rate constants of the excited cationic (k01=2.4×108 s−1) and neutral (k02=3.0×108 s−1) forms of II.
Six IPR Isomers of C90 Fullerene Captured as Chlorides: Carbon Cage Connectivities and Chlorination Patterns
Authors: Troyanov Sergey I. , Yang Shangfeng , Chen Chuanbao , Kemnitz Erhard
Published: August 2011

Three C90 fractions were isolated by multi‐step HPLC from fullerene soot obtained from direct current (DC) arc discharge of undoped graphite rods. C90 of each fraction was chlorinated with VCl4 or SbCl5 in ampoules at 290–310 °C, affording a series of C90Cln compounds. Single‐crystal X‐ray crystallography with the use of synchrotron radiation resulted in structure elucidation of seven C90Cln compounds containing six different isolated pentagon rule (IPR) C90 cages (the number of the C90 isomer is given in the parentheses): C90(46)Cl32 (I), C90(34)Cl32 (II), C90(35)Cl24 (III), and C90(35)Cl28 (IV), C90(32)Cl24 (V as co‐crystals with III), co‐crystals of C90(30)Cl22 and C90(28)Cl24 (VI), and C90(28)Cl24 (VII). Cage connectivities of C90 isomers 35 and 28 have been crystallographically confirmed for the first time. The chlorination patterns of the C90Cln molecules are discussed in terms of the formation of isolated aromatic systems and isolated CC double bonds on the fullerene cage. The distribution of six C90 isomers in three HPLC fractions is compared with data from the literature.
Hexaazatriphenylene (HAT) versus tri‐HAT: The Bigger the Better?
Authors: Juárez Rafael , Oliva María Moreno , Ramos Mar , Segura José L. , Alemán Carlos , Rodríguez‐Ropero Francisco , Curcó David , Montilla Francisco , Coropceanu Veaceslav , Brédas Jean Luc , Qi Yabing , Kahn Antoine , Ruiz Delgado M. Carmen , Casado Juan , López Navarrete Juan T.
Published: August 2011

A new hexaazatriphenylene (HAT) derivative formed by the fusion of three HAT units has been prepared and its electronic and molecular structures have been fully characterized by optical and vibrational Raman spectroscopy, electrochemistry, solid‐state UV and inverse photoemission spectroscopy (UPS and IPES), and by quantum‐chemical calculations. A comparative HAT versus tri‐HAT study was performed. The fusion of three HAT molecules causes modifications in the optical and electrochemical properties consistent with enhanced π‐electron delocalization attained in a bigger planar core. Such combined experimental and theoretical studies are useful to balance chemical design with supramolecular engineering directed to find enhanced characteristics for new organic semiconductor applications.
CO2 Insertion into Metal–Carbon Bonds: A Computational Study of RhI Pincer Complexes
Authors: Ostapowicz Thomas G. , Hölscher Markus , Leitner Walter
Published: August 2011

Catalytic carboxylation reactions that use CO2 as a C1 building block are still among the ‘dream reactions’ of molecular catalysis. To obtain a deeper insight into the factors that control the fundamental steps of potential catalytic cycles, we performed a detailed computational study of the insertion reaction of CO2 into rhodium–alkyl bonds. The minima and transition‐state geometries for 38 pincer‐type complexes were characterized and the according energies for the CC bond‐forming step were determined. The electronic properties of the Rhalkyl bond were found to be more important for the magnitude of the activation barrier than the interaction between rhodium and CO2. The charge of the alkyl‐chain carbon atom, as well as agostic and orbital interactions with the rhodium, exhibit the most pronounced influence on the energy of the transition states for the CO2 insertion reaction. By varying the backbone and the donor groups of the pincer ligand those properties can be tuned over a very broad range. Thus, it is possible to match the electronic and steric properties with the fundamental requirements of the CO2 insertion into rhodium–alkyl bonds of the ligand framework.
Nature of the Intermediates in Gold(I)‐Catalyzed Cyclizations of 1,5‐Enynes
Authors: López‐Carrillo Verónica , Huguet Núria , Mosquera Ángeles , Echavarren Antonio M.
Published: August 2011

The carbene or carbocationic nature of the intermediates in the gold‐catalyzed cycloisomerization of 1,5‐enynes can be revealed, depending on the ligands on the gold catalysts. Gold complexes with highly electron‐donating ligands promote reactions that proceed via intermediates with carbene‐like character, leading to products with a bicyclo[3.1.0]hexene skeleton. The intermediate cyclopropyl endo‐gold carbenes formed in this cyclization have been trapped, for the first time, to give biscyclopropane derivatives in a reaction that proceeds in a concerted fashion, according to DFT calculations.
Central‐to‐axial chirality transfer revealed by liquid crystals: A combined experimental and computational approach for the determination of absolute configuration of carboxylic acids with an α chirality centre
Authors: Ferrarini Alberta , Ferroni Fiammetta , Pieraccini Silvia , Rosini Carlo , Superchi Stefano , Spada Gian Piero
Published: August 2011

The conversion into 6,7‐dihydro‐5H‐dibenz[c,e]azepine (DAZ) N‐protected amides is a viable route for the determination of the absolute configuration of chiral 2‐substituted carboxylic acids. The biphenyl moiety of DAZ, besides being a probe of chirality for the electronic circular dichroism (ECD) spectroscopy, makes these systems suitable for configuration assignment by exploiting the chirality amplification which occurs in nematic liquid crystals. To assess the reliability of the liquid crystal method in detecting the absolute stereochemistry of chiral amides bound to a biphenyl group, we measured the helical twisting power of a series of DAZ‐N‐protected amides and compared these data with the results obtained from ECD measurements. We will show that the liquid crystal method, corroborated by HTP predictions, is trustworthy with our biphenyl derivatives, even when ECD spectra are ambiguous for the presence of aryl moieties displaying strong UV absorptions in the same range of the biphenyl chromophore. Chirality, 2011. © 2011 Wiley‐Liss, Inc.
Refined model of optical activity of cis‐dihydrodiol metabolites: Role of 1,3‐diene conformation in the electronic circular dichroism spectra
Authors: Kwit Marcin , Gawronski Jacek
Published: August 2011

The effect of the secondary structural feature, that is, nonplanarity of carbon–carbon double bonds, on the rotatory strength of the long‐wavelength π–π* electronic transition has been investigated for the series of monocyclic cis‐dihydrodiol arene metabolites and model compounds. The contribution from nonplanar CC bonds to the overall rotatory strength of the π–π* electronic transition is more significant than the contribution from twisted 1,3‐diene chromophore. The effect of the substitution pattern in the cyclohexadiene skeleton may be decisive for the sign of the long‐wavelength π–π* Cotton effect. Chirality, 2011. © 2011 Wiley‐Liss, Inc.
Experimental methods for measuring optical rotatory dispersion: Survey and outlook
Authors: Castiglioni Ettore , Abbate Sergio , Longhi Giovanna
Published: August 2011

The measurement of optical rotation (OR) and optical rotatory dispersion has been finding renewed interest for some years, because of advancement in computational methods and in the performance of new experiments. Here, we shortly review the traditional and most‐used experimental methods. We define and discuss the two main types of approaches in measuring OR: the intensity method and the optical null method. We report on some new results obtained by redesigning experiments based on the first approach, by adapting nonsophisticated hardware to current circular dichroism instrumentation. Chirality, 2011. © 2011 Wiley‐Liss, Inc.
Asymmetric addition of dimethylzinc to alkylidenmalonates mediated by phosphorous ligands: A new synthetic route to floral fragrances
Authors: Superchi Stefano , Marchitiello Valeria , Pisani Laura , Scafato Patrizia
Published: August 2011

Six new phosphite ligands were prepared and their efficiency as chiral ligands was investigated in the copper‐catalyzed asymmetric conjugate addition of dimethylzinc to diethyl 3‐phenylpropylidenmalonate (5), affording the addition product with ees up to 74%. Moreover, a simple and straightforward route to floral fragrances Phenoxanol, Citralis, and Nitrile Citralis in optically active form through the above cited reaction was proposed. Chirality, 2011. © 2011 Wiley‐Liss, Inc.
An alternative stereoselective synthesis of (R)‐ and (S)‐Rosaphen® via asymmetric catalytic hydrogenation
Authors: Matteoli Ugo , Beghetto Valentina , Scrivanti Alberto , Aversa Manuela , Bertoldini Matteo , Bovo Sara
Published: August 2011

We report an alternative synthesis of the two enantiomers of the floral fragrance Rosaphen®. The key intermediate 2‐methyl‐5‐phenylpentanoic acid 3 is synthesized via asymmetric hydrogenation (ee up to 99%) in the presence of an in situ prepared ruthenium catalyst containing the chiral ferrocenyl phosphine Mandyphos‐4. Chirality, 2011. © 2011 Wiley‐Liss, Inc.