bluuebunny/crossref_metadata_2025 huggingface dataset:
Stochastic suppression and stabilization of delay differential systems
Authors: Wu Fuke , Hu Shigeng
Published: May 2010

In this paper, we investigate stochastic suppression and stabilization for nonlinear delay differential system \documentclass{article}\usepackage{amssymb}\usepackage[mathscr]{euscript}\footskip=0pc\pagestyle{empty}\begin{document}${\dot{x}}(t)=f(x(t),x(t-\delta(t)),t)$\end{document}, where δ(t) is the variable delay and f satisfies the one‐sided polynomial growth condition. Since f may defy the linear growth condition or the one‐sided linear growth condition, this system may explode in a finite time. To stabilize this system by Brownian noises, we stochastically perturb this system into the nonlinear stochastic differential system dx(t)=f(x(t), x(t−δ(t)), t)dt+qx(t)dw1(t)+σ|x(t)|βx(t)dw2(t) by introducing two independent Brownian motions w1(t) and w2(t). This paper shows that the Brownian motion w2(t) may suppress the potential explosion of the solution of this stochastic system for appropriate choice of β under the condition σ≠0. Moreover, for sufficiently large q, the Brownian motion w1(t) may exponentially stabilize this system. Copyright © 2010 John Wiley & Sons, Ltd.
Unified command and control for heterogeneous marine sensing networks
Authors: Schneider Toby , Schmidt Henrik
Published: May 2010

Successful command and control (C2) of autonomous vehicles poses challenges that are unique to the marine environment, primarily highly restrictive acoustic communications throughput. To address this, the Unified C2 architecture presented here uses a highly compressed short message encoding scheme (Dynamic Compact Control Language or DCCL) to transfer commands and receive vehicle status. DCCL is readily reconfigurable to provide the flexibility needed to change commands on short notice. Furthermore, operation of multiple types of vehicles requires a C2 architecture that is both scalable and flexible to differences among platform hardware and abilities. The Unified C2 architecture uses the MOOS‐IvP autonomy system to act as a “backseat driver” of the vehicle. This provides a uniform interface to the control system on all the vehicles. Also, a hierarchical configuration system is used to allow single changes in configuration to propagate to all vehicles in operation. Status data from all vehicles are displayed visually using Google Earth, which also allows a rapid meshing of data from other sources (sensors, automatic identification system, radar, satellites) from within, as well as outside of, the MOOS‐IvP architecture. Results are presented throughout from the CCLNET08, SQUINT08, GLINT08, GLINT09, SWAMSI09, and DURIP09 experiments involving robotic marine autonomous surface craft (ASCs) and Bluefin, OceanServer, and NATO Undersea Research Centre (NURC) autonomous underwater vehicles (AUVs). © 2010 Wiley Periodicals, Inc.
The CRT is the scaling limit of unordered binary trees
Authors: Marckert Jean‐François , Miermont Grégory
Published: May 2010

We prove that a uniform, rooted unordered binary tree (also known as rooted, binary Pólya tree) with n leaves has the Brownian continuum random tree as its scaling limit for the Gromov‐Hausdorff topology. The limit is thus, up to a constant factor, the same as that of uniform plane trees or labeled trees. Our analysis rests on a combinatorial and probabilistic study of appropriate trimming procedures of trees. © 2011 Wiley Periodicals, Inc. Random Struct. Alg., 38, 467–501, 2011
Hybrid satellite–IEEE 802.16 system for mobile multimedia delivery
Authors: Gür Gürkan , Bayhan Suzan , Alagöz Fatih
Published: May 2010

This paper describes and discusses a heterogeneous system of satellite and IEEE 802.16 WiMAX networks collaborating for the efficient delivery of multimedia services. We first elaborate on the rationale behind integrated satellite and WiMAX networks with an overview of current research on interworking of satellite and 3G/Beyond 3G terrestrial networks. Following this background, we propose a diverse set of enhancements and additions into WiMAX Base Station (BS) and Multicast Broadcast Service Controller (MBSC), which allows this interworking in the multimedia delivery context. We describe a WiMAX BS downlink scheduler that considers satellite channel conditions of the dual‐mode SSs (Subscriber Station) while making resource allocation and packet scheduling. This scheduler interacts with another proposed module in MBSC, namely Satellite–Terrestrial Interaction Module, for performing these operations. Traffic for real‐time multimedia and cache‐based delivery is considered in the system. On the SS side, a lightweight signaling scheme between BS and SS for service continuity and control is presented. Copyright © 2010 John Wiley & Sons, Ltd.
Secure real‐time routing protocol with load distribution in wireless sensor networks
Authors: Ahmed Adel Ali , Fisal Norsheila Fisal
Published: May 2010

Wireless sensor network (WSN) is a wirelessad hocnetwork that consists of a very large number of tiny sensor nodes communicating with each other with limited power and memory constrain. WSN demands real‐time forwarding which means messages in the network are delivered according to their end‐to‐end deadlines (packet lifetime). Since many sensor networks will be deployed in critical applications, security is essential. Recently, many real‐time routing protocols have been proposed, but none is designed with security. This paper proposes a novel secure real‐time with load distribution (SRTLD) routing protocol that provides secure real‐time data transfer and efficient distributed energy usage in WSN. The SRTLD routing protocol ensures high packet throughput and minimized packet overhead. It has been successfully studied and verified through simulation and real test bed implementation. Copyright © 2010 John Wiley & Sons, Ltd.
Evaluation of ionization yields under gallium bombardment
Authors: Frache Gilles , Adib Brahim El , Audinot Jean‐Nicolas , Migeon Henri‐Noel
Published: May 2010

The Cameca NanoSIMS 50 is known to provide high resolution chemical mapping for negatively charged secondary ions (50–100 nm). Nevertheless, concerning positive secondary ions, the resolution is only in the 250‐nm range. In order to obtain a better lateral resolution for positive ions, a Liquid Metal Ion Gun (LMIG, Canion 31+, Orsay‐Physics, Fuveau, France) filled with gallium (Ga+) has been installed on the Cameca IMS‐6F. In the case of this study, we have measured the useful yields in inorganic samples. Limitations in the secondary ion signal intensity, which is inherent to the Gallium bombardment, can be partly balanced by using oxygen flooding, as a method to enhance the ion yield. Examples of applications are presented to demonstrate that the IMS‐6F equipped with a Gallium LMIG fulfills the requirements to be a complementary technique to the NanoSIMS. Copyright © 2010 John Wiley & Sons, Ltd.
A review of Ga+ FIB/SIMS
Authors: Giannuzzi Lucille A. , Utlaut M.
Published: May 2010

FIB/SIMS analyses has been performed and reported for well over a decade, however, only within limited research groups due to the lack of commercial FIB/SIMS instrumentation. Commercial availability of FIB/SIMS failed mainly due to two reasons: (i) the low secondary ion yields from the primary Ga+ source; and (ii) unrealistic expectations in sensitivity detection limits using the small FIB source. Despite the low yields and limits in sensitivity detection limited by the small volume of material analyzed, FIB/SIMS is extremely useful for conventional ppm SIMS analysis as well as high‐spatial resolution analyses. Copyright © 2010 John Wiley & Sons, Ltd.
The cuticular surface of D. melanogaster: ToF‐SIMS on the fly
Authors: Levine J. , Billeter J.‐C. , Krull U. , Sodhi R.
Published: May 2010

Insects rely on chemicals to communicate, regulate water balance, and provide a protective barrier against infection. Drosophila melanogaster generates hydrocarbons to perform such functions, and these compounds coat the cuticular surface of the fly. Very little is known about the surface properties of these compounds, how they are arranged and whether they are evenly or unevenly distributed. Here, we begin to address these questions using time of flight (TOF) SIMS. We demonstrate that we can identify synthetic compounds, and that we can detect male–female differences. We used polished silicon wafers as a substrate for the application of synthetic compounds, as well as dissected bits of the cuticle taken from wild‐type males and females. Application of the Bi3+ cluster source‐obtained spectra that describe the properties of synthetic compounds that served as standards. Spectra obtained from the sections of dissected cuticle were complex but sex‐based differences are evident. Thus, in principle, TOF‐SIMS will be especially informative in future studies that elucidate physical properties of the epicuticular surface of the fly. Copyright © 2010 John Wiley & Sons, Ltd.
Strategies for modeling diverse chemical reactions in molecular dynamics simulations of cluster bombardment
Authors: Kennedy Paul E. , Garrison Barbara J. , Russo Michael F. , van Duin Adri C. T.
Published: May 2010

Reaction energies for the degradation reactions of poly(methyl methacrylate) (PMMA) and for the cycloaddition of two ethylene molecules to form cyclobutane were calculated using the atomistic reactive empirical bond order potential ReaxFF,1 and the reaction energies were then compared to reaction energies from literature sources. The PMMA degradation reaction energies were from 7 to 25 kcal/mol less endothermic than the relevant literature values. The cycloaddition reaction energy was 5 kcal/mol less exothermic for ReaxFF compared to the literature value. Copyright © 2010 John Wiley & Sons, Ltd.
Molecular depth profiling of polystyrene by electrospray droplet impact
Authors: Sakai Yuji , Iijima Yoshitoki , Mukou Souichirou , Hiraoka Kenzo
Published: May 2010

The molecular depth profiling of polymer by the electrospray droplet impact (EDI) has been performed. The multiply charged water droplets with kinetic energy of ∼106 eV were irradiated on the polystyrene spin coated on silicon wafer. With EDI etching, the ablation of the target is suppressed to a minimal, i.e. the shallow surface etching with nonrecognizable damage on the surface is realized. It was found that EDI/SIMS spectra and EDI/XPS spectra for polystyrene (PS) has shown no damage accumulation on the surface. This indicates that EDI is a unique technique for surface etching of polymer materials without causing any damage to the etched surface. Copyright © 2010 John Wiley & Sons, Ltd.
Tracing propionic acid infused to rat brain via deuterium tagging—further development of a novel rodent model of autism spectrum disorders
Authors: Nie H.‐Y. , Taylor A.R. , Francis J. T. , Walzak M. J. , Lau W. M. , MacFabe D. F.
Published: May 2010

MacFabeet al.have proposed a novel rat model of autism spectrum disorders (ASDs) with intraventricular infusions of propionic acid (PPA), a gut bacterial metabolic end product and common food preservative, which produces reversible behavioral and electrographic effects coupled with increased oxidative stress and innate neuroinflammatory changes consistent with findings in ASD patients. PPA appears to be a potential environmental trigger linking the disparate behavioral, dietary, gut, metabolic and immune factors implicated in ASD. These previous studies used traditional immunohistochemical and biochemical techniques to examine increased oxidative stress and visualize neurons, reactive astrocytes, and activated microglia in hippocampus and adjacent external capsule white matter from coronally sectioned rat brain. As PPA is also an important metabolic intermediate of fatty acid beta oxidation, we have repeated the experiments with deuterium‐tagged PPA (DPPA) and employed ToF‐SIMS to trace the deuterium decoration of comparable brain regions ipsilateral to the DPPA infusion. In the present case of revealing DPPA‐induced changes in brain regions, ToF‐SIMS imaging of deuterium confirms the effectiveness of the methodology and the imaging results support the PPA‐triggered ASD rodent model. Copyright © 2010 John Wiley & Sons, Ltd.
A note on dichotomization of continuous response variable in the presence of contamination and model misspecification
Authors: Shentu Yue , Xie Minge
Published: May 2010

The purpose of this note is to raise awareness of the complexity of the practice involving dichotomization. It is well known that the regular regression models are effective tools for analyzing Gaussian‐type response variables, and researchers are often told that it is a ‘bad idea’ to practice dichotomization if continuous measurements are available. We demonstrate through special cases, however, that there is another side of the story if the response variable is contaminated. Although dichotomization causes loss of information, it can also reduce input of contamination. If the reduction of contamination input outweighs the loss of information, analysis based on dichotomization can sometimes provide better results. We derive formulas of bias and variance for binary regression estimators under a contamination model of unknown additive errors, and compare them with both the least squares and robustM‐estimators from the corresponding linear regression analysis using continuous responses. As a case study, we study extensively the case in which the observed response is contaminated by an error with a mean and a variance proportional to the mean and the variance of the uncontaminated true response. Conditions under which dichotomization is preferred are obtained. A simulation study based on a real data setting is provided, which supports the theoretical developments. Copyright © 2010 John Wiley & Sons, Ltd.
Cell Cycle Heterogeneity in the Small Intestinal Crypt and Maintenance of Genome Integrity
Authors: Pruitt Steven C. , Freeland Amy , Kudla Angela
Published: May 2010

Stem cell quiescence has been hypothesized to suppress the rate at which genetic mutations accumulate within tissues by reducing the number of divisions a cell undergoes. However, recent studies have suggested that stem cells in the small intestine are rapidly dividing. This observation raises the issue of whether replication related errors are an important contributor to the accumulation of genetic damage and, if so, how genomic integrity is maintained within the small intestine. Here, reporter-marked small intestinal epithelial cells, resulting from mini-chromosome maintenance protein 2 (Mcm2) gene driven Cre-mediated recombination, are shown to be retained at the +1 position within the crypt and to contribute to the intestinal epithelia over long periods. Additionally, we show that the rate of cycling of +1 position Mcm2-expressing stem cells is heterogeneous with cycling times ranging between 1 and 4 days. Further, this heterogeneity depends on the p53 signaling pathway and could provide the basis for retention and expansion, through niche succession and crypt fission, of genetically intact stem cells. This somatic selection process would require active cellular replication.
Analysis of Kano‐model‐based customer needs for product development
Authors: Sharif Ullah A. M. M. , Tamaki Jun'ichi
Published: May 2010

The Kano model is a useful model for integrating the Voice of the Customer into the subsequent processes of product development. This paper presents a method for analyzing customers' preferences obtained by using the Kano model. In the Kano model, customers' preferences are obtained by using a prescribed form to know whether or not a given product attribute is a Must‐be, Attractive, One‐dimensional, Indifferent, or Reverse attribute for a given product. Since the preference may vary a lot from customer to customer due to the demographic and psychographic factors, a quantitative aggregation process is needed to compute the information content of all customer answers and finally to decide the aforementioned status of each product attribute. Most of the quantitative methods developed so far deal mainly with the imprecision in the customer answers and do not address the uncertain (unknown or missing) customer answers. In fact, a significant number of customers might not be able to submit their answers on time. As a result, a significant number of answers remain unknown that manifests a great deal of uncertainty. This paper shows an approach to simulate the unknown customer answers. In addition, an approach is developed to measure the information content of customer answers integrating the real and simulated customer answers. This is helpful for identifying the correct status (Must‐be, Attractive, One‐dimensional, Indifferent, or Reverse) of each product attribute. Moreover, it is shown that the weighted average type of quantitative analysis is not suitable for quantifying the inherent complexity of customer answers obtained in accordance with the Kano model. © 2010 Wiley Periodicals, Inc. Syst Eng 14: 154–172, 2011
SmI2‐induced cyclizations and their applications in natural product synthesis
Authors: Nakata Tadashi
Published: May 2010

Since the isolation of brevetoxin‐B, a red tide toxin, many bioactive marine natural products featuring synthetically challenging trans‐fused polycyclic ether ring systems have been reported. We have developed SmI2‐induced cyclization of β‐alkoxyacrylate with aldehyde, affording 2,6‐syn‐2,3‐trans‐tetrahydropyran (THP) or 2,7‐syn‐2,3‐trans‐oxepane with complete stereoselection, as a key reaction of efficient iterative and bi‐directional strategies for the construction of these polycyclic ethers. This reaction is also applicable to the synthesis of 3‐, 5‐, and 6‐methyl‐THPs and 3,5‐dimethyl‐THP. The synthesis of 2‐methyl‐ and 2,6‐dimethyl‐THPs was accomplished by means of a unique methyl insertion. Recently, the SmI2‐induced cyclization was extended to similar reactions using β‐alkoxyvinyl sulfone and sulfoxide. Reaction of (E)‐ and (Z)‐β‐alkoxyvinyl sulfone‐aldehyde afforded 2,6‐syn‐2,3‐trans‐ and 2,6‐syn‐2,3‐cis‐ THPs, respectively. Reaction of (E)‐β‐alkoxyvinyl (R)‐ and (S)‐sulfoxides gave 2,6‐anti‐2,3‐cis‐ and 2,6‐syn‐2,3‐trans‐THPs, respectively. Reaction of (Z)‐β‐alkoxyvinyl (R)‐sulfoxides gave 2,6‐syn‐2,3‐cis‐THP and an olefinic product, while that of (Z)‐β‐alkoxyvinyl (S)‐sulfoxide afforded a mixture of many products. These SmI2‐induced cyclizations have been applied to the total syntheses of various natural products, including brevetoxin‐B, mucocin, pyranicin, and pyragonicin. Synthetic studies on gambierol and maitotoxin are also introduced. © 2010 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 10: 159–172; 2010: Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/tcr.200900027
Recent progress in a chiral multinucleating system utilizing tartaric acid esters
Authors: Ukaji Yutaka , Inomata Katsuhiko
Published: May 2010

In order to develop a practical method for the construction of chiral molecules, we have designed a novel chiral reaction system possessing multi‐metal centers utilizing tartaric acid ester as a chiral auxiliary. Based on this concept, we have developed an asymmetric 1,3‐dipolar cycloaddition reaction of azomethine imines, an asymmetric hetero Diels‐Alder reaction of nitroso compounds, an asymmetric Diels‐Alder reaction of o‐quinodimethanes. Furthermore, an asymmetric nucleophilic addition of alkynylzinc reagents, prepared in situ from dialkylzinc and 1‐alkynes, to nitrones was achieved with high level of stereocontrol. In the last case, the addition of methylzinc salt of a product‐like racemic hydroxylamine was found to be effective for unprecedented enhancement of enantioselectivity. © 2010 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 10: 173–187; 2010: Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/tcr.201000002
Environmental toxicity testing of contaminated soil based on microcalorimetry
Authors: Gruiz K. , Feigl V. , Hajdu Cs. , Tolner M.
Published: May 2010

Contaminated site assessment and monitoring requires efficient risk‐management tools including innovative environmental toxicity tests. The first application of microcalorimetry for toxicity testing draw the attention to a possible new tool to increase sensitivity, to eliminate matrix effect and to study effect‐mechanism. A Thermal Activity Monitor (TAM) microcalorimeter was used for measuring the heat production of various test organisms when getting in contact with sterile toxic soils. Well known bacterial (Azomonas agilis), animal (Folsomia candida) and plant test organisms (Sinapis alba) were tested for heat production. The heat response of selected testorganisms was measured in case of metal (Cu and Zn) and organic pollutant (Diesel oil, DBNPA and PCP) contaminated soils. In addition to the quantitative determination of the heat production, the mechanism of the toxic effect can be characterized from the shape of the power‐time curve (slope of the curve, height and time of the maximum). In certain concentration ranges the higher the pollutant concentration of the soil the lower the maximum of the time‐heat curve. At low pollutant concentrations an increased heat production was measured in case of A. agile and 20 and 200 mg Zn kg−1 soil. The microcalorimetric testing was more sensitive in all cases than the traditional test methods. Our results showed that the microcalorimetric test method offers a new and sensitive option in environmental toxicology, both for research and routine testing. © 2010 Wiley Periodicals, Inc. Environ Toxicol 2010.
Responses of AChE and GST activities to insecticide coexposure in Carassius auratus
Authors: Wang Chao , Lu Guanghua , Cui Jing
Published: May 2010

Organophosphates and carbamates are widely used pesticides and play an important role in global agriculture. The misuse of these compounds has caused environmental problems and has had a negative impact on wildlife. In this study, the in vivo effects of commercial chlorpyrifos and isoprocarb on acetylcholinesterase (AChE) and glutathione S‐transferase (GST) activities in goldfish (Carassius auratus) were investigated. Muscle and brain AChE activity was significantly inhibited by chlorpyrifos and isoprocarb (alone and in combination) after 2, 5, 10, and 15 days of exposure, and obvious concentration‐response and time‐response relationships were obtained. Gill GST activity was significantly inhibited by chlorpyrifos and isoprocarb (single compounds and in combination), however, concentration dependence and time dependence were not apparent. The joint effect of chlorpyrifos/isoprocarb was additive with regard to AChE activity inhibition and was antagonistic with regard to GST activity inhibition. © 2010 Wiley Periodicals, Inc. Environ Toxicol, 2012.
First‐trimester umbilical vein blood flow in pregnancies with low serum pregnancy‐associated plasma protein‐A levels: an early predictor of fetal growth restriction
Authors: Rizzo G. , Capponi A. , Pietrolucci M. E. , Capece A. , Arduini D.
Published: May 2010

Objective

To investigate umbilical vein blood flow (UVBF) during the first trimester in pregnancies with low serum pregnancy‐associated plasma protein‐A (PAPP‐A) levels and to relate umbilical vein (UV) diameter, time‐averaged maximum velocity (TAMXV) and UVBF values to the subsequent development of fetal intrauterine growth restriction (IUGR).

Methods

UVBF assessment was performed at 11 + 0 to 13 + 6 weeks' gestation in 102 singleton pregnancies with PAPP‐A concentrations of < 0.3 multiples of the median. UV diameter, UV‐TAMXV and UVBF were calculated and analyzed in relation to pregnancy outcome.

Results

Pregnancy outcomes were: 51 pregnancies with birth weight ≥ 10th centile (Group A), 30 pregnancies with birth weight < 10th centile with normal Doppler in the umbilical artery throughout gestation (Group B) and 21 pregnancies with birth weight < 10th centile and abnormal umbilical artery Doppler later in gestation (Group C). No differences were found in PAPP‐A levels between groups. Group C fetuses exhibited significantly lower values of UV‐TAMXV (z‐score − 1.99 SDs, t = 8.527, P ≤ 0.0001) and UVBF (z‐score − 0.97 SDs, t = 7.420, P ≤ 0.0001) in comparison with normal reference ranges, while no differences were found in Groups A or B.

Conclusions

Decreased UV‐TAMXV and UVBF at 11 + 0 to 13 + 6 weeks' gestation identify fetuses at risk of developing IUGR among pregnancies with low levels of PAPP‐A. Copyright © 2010 ISUOG. Published by John Wiley & Sons, Ltd.
Modulation classification for asynchronous high‐order QAM signals
Authors: Shi Qinghua , Gong Yi , Guan Yong Liang
Published: May 2010

Automatic modulation classification (MC) is beneficial to digital radio receivers. Conventional MC schemes usually assume that perfect synchronization has been accomplished and then rely on certain statistical characteristics to distinguish different modulation formats. In practice, however, this perfect synchronization assumption is not reasonable since modulation classifiers operate in a non‐cooperative manner and therefore, the receiver has little prior knowledge about a transmitted signal and no training is available. In this paper, we first address asynchronous MC for high‐order QAMs through blind time synchronization. A characteristic function (CF) based approach is proposed to improve the performance of the conventional cumulant method. We then move on to consider asynchronous MC in the presence of frequency offset. We propose a hybrid MC scheme based on blind time synchronization, differential processing, and cumulants to solve this difficult problem. Copyright © 2010 John Wiley & Sons, Ltd.
Models of the reading process
Authors: Rayner Keith , Reichle Erik D.
Published: May 2010

Reading is a complex skill involving the orchestration of a number of components. Researchers often talk about a ‘model of reading’ when talking about only one aspect of the reading process (e.g., models of word identification are often referred to as ‘models of reading’). Here, we review prominent models that are designed to account for (1) word identification, (2) syntactic parsing, (3) discourse representations, and (4) how certain aspects of language processing (e.g., word identification), in conjunction with other constraints (e.g., limited visual acuity, saccadic error) guide readers' eyes. Unfortunately, it is the case that these various models addressing specific aspects of the reading process seldom make contact with models dealing with other aspects of reading. Thus, for example, the models of word identification seldom make contact with models of eye‐movement control, and vice versa. Although this may be unfortunate in some ways, it is quite understandable in other ways because reading itself is a very complex process. We discuss prototypical models of aspects of the reading process in the order mentioned above. We do not review all possible models but rather focus on those we view as being representative and most highly recognized.WIREs Cogn Sci2010 1 787–799

This article is categorized under:

Linguistics > Computational Models of Language

Psychology > Language
Models of processing: discourse
Authors: Garnham Alan
Published: May 2010

This article discusses models of discourse processing, primarily from a psycholinguistic perspective, though considerations from the other cognitive sciences are mentioned where appropriate. It also touches on issues of discourse representation, because questions about representation and questions about process are closely intertwined. The origins of an interest in questions about discourse are identified in Bransford's ideas from the early 1970s. Their development into more detailed models of discourse processing is discussed, and detailed descriptions are given of, in particular, anaphor processing and, to a lesser extent the establishment of coherence. Some issues that arise in connection with the production of discourse are briefly discussed, as are their relation to dialog rather than to monolog.WIREs Cogn Sci2010 1 845–853

This article is categorized under:

Linguistics > Language in Mind and Brain

Psychology > Language
Language production
Authors: Ferreira Victor S.
Published: May 2010

Linguistic expressions are produced through a multicomponent multistage process. This article describes the major components of the language‐production process and discusses issues of current research focus. General mechanisms of word and sentence production are described. This is followed by discussion of language production in conversation, different modes of production (written production, sign language, monitoring, bilingualism, aphasia, corpus research), and the relationship of language‐production mechanisms to other cognitive systems (eye movements, attention, memory, gesture), before ending with concluding thoughts.WIREs Cogn Sci2010 1 834–844

This article is categorized under:

Linguistics > Language in Mind and Brain

Psychology > Language
Accurate repair of non‐cohesive, double strand breaks in Saccharomyces cerevisiae: enhancement by homology‐assisted end‐joining
Authors: Moscariello Mario , Florio Carolina , Pulitzer John F.
Published: May 2010

Although the joining of blunt ends in yeast by non‐homologous end joining (NHEJ) is reported to be inefficient in comparison to cohesive‐end joining (Boulton and Jackson, 1996), we find that efficiency varies greatly, depending on strain, growth phase and sequence. In particular, the levels of efficiency of recircularization of a plasmid linearized by non‐cohesive cleavage is augmented to that of cohesive end joining if the cleavage cut site is flanked by sequences present in the genome. We call this enhancement ‘homology‐assisted end joining’ (HAEJ), which depends on components of the NHEJ repair pathway and, in some cases, on components of the homologous recombination (HR) pathway and on Htl1 a component of the remodels structure of chromatin (RSC) complex. The homologous genome sequences are not used as templates for repair DNA synthesis, but may facilitate end‐to‐end collision and ligation by providing a track for guided diffusion. Copyright © 2010 John Wiley & Sons, Ltd.
Fine regulation of Saccharomyces cerevisiae MAPK pathways by post‐translational modifications
Authors: Molina María , Cid Víctor J. , Martín Humberto
Published: May 2010

Saccharomyces cerevisiae has been widely used as a model eukaryotic organism to elucidate the molecular mechanisms that operate upon activation of signalling pathways. For over two decades, many clues to the regulation of mitogen‐activated protein kinase (MAPK) pathways have derived from basic research in yeast. Here we review aspects of MAPK pathway fine‐tuning, such as the functional implication of feedback loops or regulatory inputs from other pathways, mediated by post‐transcriptional modifications on their components. The impact of recent phosphoproteomic approaches in this particular field is also discussed. Copyright © 2010 John Wiley & Sons, Ltd.
Synthesis of 1,2,4,5‐Benzenetetrasulfonic Acid (H4B4S) and its Implementation as a Linker for Building Metal‐Organic Frameworks on the Example of [Cu2(B4S)(H2O)8]·0.5H2O
Authors: Muesmann Thomas W. T. , Mietrach Andrea , Christoffers Jens , Wickleder Mathias S.
Published: May 2010

Benzene 1,2,4,5‐tetrasulfonic acid (H4B4S) was prepared in two steps starting from 1,2,4,5‐Tetrachlorobenzene. Slow evaporation of an aqueous reaction mixture of H4B4S and Cu2(OH)2(CO3) led to light green single crystals of [Cu2(B4S)(H2O)8]·0.5H2O. X‐ray single crystal investigations revealed the compound to be triclinic [P$\bar{1}$, Z = 1, a = 710.0(1), b = 713.7(1), c = 1077.1(2) pm, α = 98.41(2)°, β = 102.91(2)°, γ = 100.69(2)°]. In the crystal structure the Cu2+ ions are coordinated by four water molecules and two monodentate sulfonate anions yielding a tetragonally distorted [CuO6] octahedron. The anions are connected to further copper ions leading to ladder shaped chains running along the [100] direction. According to DTA/TG investigations the dehydration of the compound is finished at 240 °C and the decomposition of the anhydrous sulfonate starts at 340 °C.
Synthesis and Crystal Structure of a New Dinuclear Iron(III) Complex: [Fe2O(PhCO2)2(2,2′‐bpy)2(N3)2]·H2O
Authors: Wu Qing‐Ran , Du Chuan‐Qin , Hu Huai‐Ming , Xu Bing
Published: May 2010

By using a precursor complex [Fe3O(PhCO2)6(H2O)3]NO3 as starting material and 2,2′‐bpy (= 2,2′‐bipyridine) as rigid chelating ligand, the new dinuclear iron‐oxido complex [Fe2O(PhCO2)2(2,2′‐bpy)2(N3)2]·H2O (1) was synthesized and structurally characterized. The reaction of [Fe3O(PhCO2)6(H2O)3]NO3 with 2,2′‐bpy and sodium azide in 1:3:3 ratio gave the dinuclear complex 1, whereas a 1:6:3 ratio reaction system only gave the complex [Fe(2,2′‐bpy)3]3+, which indicated that 2,2′‐bipyridine plays a crucial function in the nuclear forming procedure. Meanwhile, the N3– ligands take up the chelating domain of oxygen and reduce the nucleation. Different π–π interactions exist in 1, which extend its structure to a three dimensional supramolecular framework.
Self‐assembly and Properties of Three Novel Supramolecular Architectures: Dimensional Increase of Cd/Ag 4‐Formylbenzoate Complexes Controlled by Hexamethylenetetramine
Authors: Deng Zhao‐Peng , Huo Li‐Hua , Xu Ying‐Ming , Gao Shan , Zhao Hui
Published: May 2010

The reactions of Cd(NO3)2 or AgNO3 with hexamethylenetetramine (hmt) and 4‐formylbenzoic acid (4‐Hfba) yield three novel supramolecular architectures [Cd(4‐fba)2(μ2‐hmt)(H2O)]n (1), [Cd(4‐fba)2(μ2‐hmt)(H2O)2]n·nH2O (2), and [Ag(4‐fba)(μ3‐hmt)]n·2nH2O (3), which were characterized by elemental analysis, IR spectroscopy, luminescence spectroscopy, thermogravimetry, and powder as well as single‐crystal X‐ray diffraction. Structural analyses show that both complexes 1 and 2 have an one‐dimensional motif, except for a distinction arising from the coordination spheres and the bent angles of N–Cd–N. Both complexes are featuring three‐dimensional supramolecular frameworks through hydrogen bonding interactions, additional π–π interactions exist for complex 2. Complex 3 contains a classic undulating two‐dimensional Ag‐hmt layer, which is further axially connected by 4‐fba– linkers to give a 3D (3,5)‐connected gra net. The luminescence spectra of complexes 1 and 2 show a similar emission in the blue region at room temperature. Furthermore, efforts to further study the postsynthetic modification of these complexes are underway in our laboratory owing to the presence of the pendant formyl groups.
β3‐Adrenergic Signaling Acutely Down Regulates Adipose Triglyceride Lipase in Brown Adipocytes
Authors: Deiuliis Jeffrey A. , Liu Li‐Fen , Belury Martha A. , Rim Jong S. , Shin Sangsu , Lee Kichoon
Published: May 2010

Mice exposed to cold rely upon brown adipose tissue (BAT)‐mediated nonshivering thermogenesis to generate body heat using dietary glucose and lipids from the liver and white adipose tissue. In this report, we investigate how cold exposure affects the PI3 K/Akt signaling cascade and the expression of genes involved in lipid metabolism and trafficking in BAT. Cold exposure at an early time point led to the activation of the PI3 K/Akt, insulin‐like signaling cascade followed by a transient decrease in adipose triglyceride lipase (ATGL) gene and protein expression in BAT. To further investigate how cold exposure‐induced signaling altered ATGL expression, cultured primary brown adipocytes were treated with the β3‐adrenergic receptor (β3AR) agonist CL 316,243 (CL) resulting in activation of PI3 K/Akt, ERK 1/2, and p38 signaling pathways and significantly decreased ATGL protein levels. ATGL protein levels decreased significantly 30 min post CL treatment suggesting protein degradation. Inhibition of PKA signaling by H89 rescued ATGL levels. The effects of PKA signaling on ATGL were shown to be independent of relevant pathways downstream of PKA such as PI3 K/Akt, ERK 1/2, and p38. However, CL treatment in 3T3‐L1 adipocytes did not decrease ATGL protein and mRNA expression, suggesting a distinct response in WAT to β3‐adrenergic agonism. Transitory effects, possibly attributed to acute Akt activation during the early recruitment phase, were noted as well as stable changes in gene expression which may be attributed to β3‐adrenergic signaling in BAT.
Pictorial Essay: Imaging of Peripheral Nerve Sheath Tumours
Authors: Chee Daniel W.Y. , Peh Wilfred C.G. , Shek Tony W.H.
Published: May 2010

Peripheral nerve sheath tumours (PNST) may be benign or malignant. Benign PNSTs include neurofibroma and schwannoma. Neurogenic tumours share certain characteristic imaging features, suggested by a fusiform-shaped mass with tapered ends, the “split-fat” sign, atrophy of the muscles supplied by the involved nerve, the “fascicular sign,” and the “target sign”; these imaging features are best demonstrated on magnetic resonance imaging. This pictorial essay emphasizes the characteristic signs and distinguishing features of PNSTs on imaging.
Preliminary results from U–Th dating of glacial–interglacial deposition cycles in a silica speleothem from Venezuela
Authors: Lundberg J. , Brewer-Carias C. , McFarlane D.A.
Published: May 2010

Recent explorations in Cueva Charles Brewer, a large cave in a sandstone tepui, SE Venezuela, have revealed silica biospeleothems of unprecedented size and diversity. Study of one — a sub-spherical mass of opaline silica — reveals a complex, laminated internal structure consisting of three narrow dark bands alternating with two wider light bands. Uranium–thorium dating has produced 3 stratigraphically correct dates on the light bands from 298 ± 6 (MIS 9) to 390 ± 33 ka (MIS 11). U concentration is only 30–110 ppb. Initial234U/238U ratios are high and increase over time from 1.8 to 5.3. Growth rate is very low, the fastest, at 0.37 ± 0.23 mm/ka, in MIS 9. Trace element and heavy metal content of the dark bands is distinctly higher than that of the light bands. It is hypothesized that the dark and light bands correlate with drier/glacial and wetter/interglacial periods, respectively, and that this sample probably began to grow in MIS 13. The cave is in a region that straddles a regionally important ecotone: the speleothem isotopic and trace element variations may preserve a useful paleoclimatic signal. This is the first published suite of U–Th dates from a single silica speleothem and the longest Quaternary record for this region.
Early Holocene dune activity linked with final destruction of Glacial Lake Minong, eastern Upper Michigan, USA
Authors: Loope Henry M. , Loope Walter L. , Goble Ronald J. , Fisher Timothy G. , Jol Harry M. , Seong J.C.
Published: May 2010

The early Holocene final drainage of glacial Lake Minong is documented by 21 OSL ages on quartz sand from parabolic dunes and littoral terraces and one radiocarbon age from a lake sediment core adjacent to mapped paleoshorelines in interior eastern Upper Michigan. We employ a simple model wherein lake-level decline exposes unvegetated littoral sediment to deflation, resulting in dune building. Dunes formed subsequent to lake-level decline prior to stabilization by vegetation and provide minimum ages for lake-level decline. Optical ages range from 10.3 to 7.7 ka; 15 ages on dunes adjacent to the lowest Lake Minong shoreline suggest final water-level decline ∼ 9.1 ka. The clustering of optical ages from vertically separated dunes on both sides of the Nadoway–Gros Cap Barrier around 8.8 ka and a basal radiocarbon date behind the barrier (8120 ± 40 14C yr BP [9.1 cal ka BP]) support the hypothesis that the barrier was breached and the final lake-level drop to the Houghton Low occurred coincident with (1) high meltwater flux into the Superior basin and (2) an abrupt, negative shift in oxygen isotope values in Lake Huron.
The Construction of Northumberland House and the Patronage of its Original Builder, Lord Henry Howard, 1603–14
Authors: Guerci Manolo
Published: May 2010

This paper affords a complete analysis of the construction of the original Northampton (later Northumberland) House in the Strand (demolished in 1874), which has never been fully investigated. It begins with an examination of the little-known architectural patronage of its builder, Lord Henry Howard, 1st Earl of Northampton from 1603, one of the most interesting figures of the early Stuart era. With reference to the building of the contemporary Salisbury House by Sir Robert Cecil, 1st Earl of Salisbury, the only other Strand palace to be built in the early seventeenth century, textual and visual evidence are closely investigated. A rediscovered elevational drawing of the original front of Northampton House is also discussed. By associating it with other sources, such as the first inventory of the house (transcribed in the Appendix), the inside and outside of Northampton House as Henry Howard left it in 1614 are re-configured for the first time.
The movement and distribution of Helicoverpa armigera (Hübner) larvae on pea plants is affected by egg placement and flowering
Authors: Perkins L.E. , Cribb B.W. , Hanan J. , Zalucki M.P.
Published: May 2010

The distribution and movement of 1st instar Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) larvae on whole garden pea (Pisum sativum L.) plants were determined in glasshouse trials. This economically-important herbivore attacks a wide variety of agricultural, horticultural and indigenous plants. To investigate the mechanisms underlying larval intra-plant movement, we used early-flowering and wild-type plant genotypes and placed eggs at different vertical heights within the plants, one egg per plant. Leaf water and nitrogen content and cuticle hardness were measured at the different plant heights. Of 92 individual larvae, 41% did not move from the node of eclosion, 49% moved upwards and 10% moved downwards with the distance moved being between zero and ten plant nodes. Larvae from eggs placed on the lower third of the plant left the natal leaf more often and moved further than larvae from eggs placed in the middle or upper thirds. The low nutritive value of leaves was the most likely explanation for more movement away from lower plant regions. Although larvae on flowering plants did not move further up or down than larvae on non-flowering plants, they more often departed the leaflet (within a leaf) where they eclosed. The final distribution of larvae was affected by plant genotype, with larvae on flowering plants found less often on leaflets and more often on stipules, tendrils and reproductive structures. Understanding intra-plant movement by herbivorous insects under natural conditions is important because such movement determines the value of economic loss to host crops. Knowing the behaviour underlying the spatial distribution of herbivores on plants will assist us to interpret field data and should lead to better informed pest management decisions.
Spatial clustering and associations of two savannah tsetse species, Glossina morsitans submorsitans and Glossina pallidipes (Diptera: Glossinidae), for guiding interventions in an adaptive cattle health management framework
Authors: Sciarretta A. , Tikubet Getachew , Baumgärtner J. , Girma Melaku , Trematerra P.
Published: May 2010

The paper deals with tsetse (family Glossinidae) control and aims at improving the methodology for precision targeting interventions in an adaptive pest management system. The spatio-temporal distribution of Glossina morsitans submorsitans Newstead, and Glossina pallidipes Austen, at Ethiopia's Keto pilot site, is analyzed with the spatial analysis by distance indices (SADIE) methodology that focus on clustering and spatial associations between species and between sexes. Both species displayed an aggregated distribution characterised by two main patches in the south and an extended gap in the north. Spatial patterns were positively correlated and stable in most cases, with the exception of the early dry season and the short rainy season when there were differences between the species and sexes. For precision targeting interventions, the presented methods here are more effective than the previously used geostatistical analyses for identifying and delimiting hot spots on maps, measuring shapes and sizes of patches, and discarding areas with low tsetse density. Because of the improved knowledge on hot spot occurrences, the methods allow a better delimitation of the territory for control operations and a more precise computation of the number of the relatively expensive traps used for monitoring and control purposes.
A six-year study of insect emergence from temporary flooded wetlands in central Sweden, with and without Bti-based mosquito control
Authors: Vinnersten T.Z. Persson , Lundström J.O. , Schäfer M.L. , Petersson E. , Landin J.
Published: May 2010

In temporary wetlands in the River Dalälven floodplains, recurrent but irregular floods induce massive hatching of the flood-water mosquito Aedes sticticus, which causes enormous nuisance. Flood-water mosquito control using the biological larvicide Bacillus thuringiensis var. israelensis (Bti) was commenced in parts of the floodplains during 2002, and here we report the first six years of full-season monitoring of general insect emergence from temporary wetlands with and without treatment. Emergence traps, which were emptied weekly, were used from May to September each year. A total of 137,153 insects of 13 taxonomic orders were collected. Diptera was highly dominating and especially the sub-order Nematocera with 18 families was a very prominent taxon. Bti-treatment effects were analysed by taxonomic order, by sub-order in Diptera and Hemiptera, and by family for Nematocera and Coleoptera for the whole study period. We found no significant negative effects of Bti treatments on the production of insects by taxonomic order, with the exception of Coleoptera in the long term. However, no significant negative effects were found for the Coleoptera families, neither in the short term nor in the long term. There was no significant negative treatment effect on Nematocera production, neither when analyzed for the whole sub-order nor when analyzed by family. However, abundance of Ceratopogonidae was significantly higher in experimental than in reference wetlands. We conclude that Bti-treatment effects on insect production may be minute in comparison to other environmental factors structuring the insect fauna of the temporary wetlands studied.
A tale of two trapping methods:Helicoverpaspp. (Lepidoptera, Noctuidae) in pheromone and light traps in Australian cotton production systems
Authors: Baker G.H. , Tann C.R. , Fitt G.P.
Published: May 2010

Pheromone and light traps have often been used in ecological studies of two major noctuid pests of agriculture in Australia,Helicoverpa armigeraandH. punctigera. However, results from these two methods have rarely been compared directly. We set pheromone and light traps adjacent to or amongst cotton and various other crops for 10–11 years in the Namoi Valley, in northern New South Wales, Australia. Catches in pheromone traps suggested a major peak in (male) numbers ofH. punctigerain early spring, with relatively few moths caught later in the summer cropping season. In contrast, (male)H. armigerawere most abundant in late summer. Similar trends were apparent for catches of both male and femaleH. armigerain light traps, but both sexes ofH. punctigerawere mostly caught in mid-summer. For both species, males were more commonly caught than females. These catch patterns differed from some previous reports. At least three generations of both species were apparent in the catches. There was some evidence that the abundance of later generations could be predicted from the size of earlier generations; but, unlike previous authors, we found no positive relationships between local winter rainfall and subsequent catches of moths, nor did we find persuasive evidence of correlations between autumn and winter rainfall in central Australia and the abundance of subsequent 1st generationH. punctigeramoths. FemaleH. punctigerawere consistently more mature (gravid) and more frequently mated than those ofH. armigera. Overall, our results highlight the variability in trap catches of these two species and question the use of trap catches and weather as predictors of future abundance in cropping regions.