bluuebunny/crossref_metadata_2025_split huggingface dataset:
Collection and storage of CO2 for 13C analysis: an application to separate soil CO2 efflux into root‐ and soil‐derived components
Authors: Midwood Andrew J. , Gebbing Thomas , Wendler Renate , Sommerkorn Martin , Hunt John E. , Millard Peter 
Published: October 2006

AbstractSoil surface CO2 efflux is comprised of CO2 from (i) root respiration and rhizosphere microbes and (ii) heterotrophic respiration from the breakdown of soil organic matter (SOM). This efflux may be partitioned between these sources using δ13C measurements. To achieve this, continuous flow isotope ratio mass spectrometry can be used and, in conjunction with 10 mL septum‐capped vials, large numbers of samples may be analysed using a Finnigan MAT DeltaplusXP interfaced to a Gas Bench II. Here we describe a number of advances to facilitate such work, including: (i) a technique for monitoring mass spectrometer performance, (ii) improvements to sample storage, and (iii) a gas‐handling system for incubating and sampling the CO2 derived from roots and soils. Mass spectrometer performance was monitored using an automated refillable vial. Compressed air analysed with this system had mean δ13C of −9.61 ± 0.16‰ (± 1σ, n = 28) collected over four runs. Heating the butyl rubber septa used to seal the vials at 105°C for 12 h improved the sample storage. After air transportation over 12 days, the isotope composition of the CO2 at ambient concentrations was unchanged (before: −35.2 ± 0.10‰, n = 4; after: −35.3 ± 0.10‰, n = 15); without heat treatment of the septa the CO2 became slightly enriched (–35.0 ± 0.14‰, n = 15). The linearity of the Gas Bench II was found to decline above 8000 µmol CO2 mol–1. To stay within a linear range and to allow the incubation of soil and root material we describe a gas‐handling system based around a peristaltic pump. Finally, we demonstrate these methods by growing a C‐4 grass (Guinea grass, Panicum maximum Jacq.) in a C‐3 soil. Root respiration was found to contribute between 5 and 22% to the soil surface CO2 efflux. These methodologies will facilitate experiments aimed at measuring the isotopic composition of soil‐derived CO2 across a range of ecological applications. Copyright © 2006 John Wiley & Sons, Ltd.
Screening forin vivometabolites of isovalertatin family oligosaccharides in rats by liquid chromatography coupled to electrospray ionization tandem mass spectrometry
Authors: Si Duanyun , Zhong Dafang , Liu Changxiao 
Published: October 2006

AbstractLiquid chromatography/electrospray ionization tandem mass spectrometry (LC/MSn) was used to identify trace levels ofin vivometabolites after the administration of isovalertatin M23 or isovalertatin D23 to rats. The biosamples of urine, feces, and ileum incubation were pre‐treated by solid‐phase extraction (SPE), and then chromatographed with a reversed‐phase C8column with acetonitrile/1.5 mM aqueous ammonia (18:82, v/v) as the mobile solvent. The parent drug and the possible metabolites were identified by two independent qualitative parameters, retention time and collision‐induced dissociation product ions. Nine and seven metabolites were successfully characterized from biosamples after administration of isovalertatins M23 and D23, respectively, to rats. The metabolism seemed to take place in the rat intestinal tract, and metabolic pathways were identified including isovaleryl de‐esterification and hydrolysis ofα‐glucose units located either at the reducing or the non‐reducing terminus. Copyright © 2006 John Wiley & Sons, Ltd.
Determination of therapeutics with growth‐hormone secretagogue activity in human urine for doping control purposes
Authors: Thevis Mario , Wilkens Frauke , Geyer Hans , Schänzer Wilhelm 
Published: October 2006

AbstractThe administration of growth‐promoting agents such as human growth hormone as well as compounds with respective secretagogue activity is prohibited in sports according to the regulations of the World Anti‐Doping Agency. Acetylcholine esterase inhibitors have been demonstrated to stimulate growth‐hormone secretion in elderly humans, and new orally active drugs have been developed to provide alternatives to therapeutic injections of growth‐hormone preparations. Preventive anti‐doping strategies include method development for emerging drugs and potentially misused compounds. Hence, the mass spectrometric dissociation behavior of three acetylcholine esterase inhibitors (donepezil, galantamine and rivastigmine) and a structural analogue to the growth‐hormone secretagogue SM‐130686 were studied using high‐resolution/high‐accuracy orbitrap mass spectrometry. These data provided substantial information for screening procedures, complementing common methods of sports drug testing. Using liquid‐liquid extraction and subsequent liquid chromatography/tandem mass spectrometry (LC/MS/MS) analysis, the four target analytes were determined at urinary concentrations of 15–20 ng/mL, recoveries ranged from 55–97%, and assay precisions were calculated at 5.2–15.8% (intraday) and 10.2–21.6% (interday) for all compounds. The applicability of the developed assay to authentic urine specimens was tested using two administration study urine samples after application of Reminyl (galantamine) and Aricept (donepezil). In both cases, the administered drug and the respective desmethylated metabolites were detected. Copyright © 2006 John Wiley & Sons, Ltd.
Direct high‐resolution peptide and protein analysis by desorption electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry
Authors: Bereman Michael S. , Nyadong Leonard , Fernandez Facundo M. , Muddiman David C. 
Published: October 2006

AbstractWe report the first coupling of a desorption electrospray ionization (DESI) ion source to Fourier transform ion cyclotron resonance mass spectrometry (ESI‐FT‐ICR‐MS) for high‐resolution protein analysis. The DESI FT‐ICR‐MS source design is described in detail along with preliminary data obtained on peptides and proteins ranging from 1 to 5.7 kDa. Copyright © 2006 John Wiley & Sons, Ltd.
ℒ︁2‐Stabilization of continuous‐time linear systems with saturating actuators
Authors: Castelan E. B. , Tarbouriech S. , Gomes da Silva J. M. , Queinnec I. 
Published: October 2006

AbstractThis paper addresses the problem of controlling a linear system subject to actuator saturations and to ℒ︁2‐bounded disturbances. Linear matrix inequality (LMI) conditions are proposed to design a state feedback gain in order to satisfy the closed‐loop input‐to‐state stability (ISS) and the closed‐loop finite gain ℒ︁2stability. By considering a quadratic candidate Lyapunov function, two particular tools are used to derive the LMI conditions: amodified sector condition, which encompasses the classical sector‐nonlinearity condition considered in some previous works, andFinsler's Lemma, which allows to derive stabilization conditions which are adapted to treat multiple objective control optimization problems in a potentially less conservative framework. Copyright © 2006 John Wiley & Sons, Ltd.
Galerkin‐based sliding mode tracking control of non‐minimum phase DC‐to‐DC power converters
Authors: Fossas Enric , Olm Josep M. , Zinober Alan S. , Shtessel Yuri B. 
Published: October 2006

AbstractOutput voltage control of nonlinear DC‐to‐DC power converters is handicapped by the non‐minimum phase character exhibited by these systems. The problem has been usually solved with indirect control strategies that work through the input current. In this article, we report a robust control methodology that uses Galerkin‐based sliding manifolds, which use full state reference profiles and an estimate of the disturbed load parameter. The sliding surface incorporates a first‐order Galerkin approximation of the input current that provides robustness to piecewise constant load perturbations by dynamic compensation: it allows on‐line accommodation to the action of the load estimator. This results in high‐accuracy tracking of periodic references at the output resistance of boost and buck‐boost converters. Copyright © 2006 John Wiley & Sons, Ltd.
Vision‐only control and guidance for aircraft
Authors: Proctor Alison A. , Johnson Eric N. , Apker Thomas B. 
Published: October 2006

AbstractAn unmanned aerial vehicle usually carries an array of sensors whose output is used to estimate vehicle attitude, velocity, and position. This paper details the development of guidance, navigation, and control strategies for a glider, which is capable of flying a terminal trajectory to a known fixed object using only a single vision sensor. Controlling an aircraft using only vision presents two unique challenges: First, absolute state measurements are not available from a single image; and second, the images must be collected and processed at a high rate to achieve the desired controller performance. The image processor utilizes an integral image representation and a rejective cascade filter to find and classify simple features in the images, reducing the image to the most probable pixel location of the destination object. Then, an extended Kalman filter uses measurements obtained from a single image to estimate the states that would otherwise be unobservable in a single image. In this research, the flights are constrained to keep the destination object in view. The approach is validated through simulation. Finally, experimental data from autonomous flights of a glider, instrumented only with a single nose‐mounted camera, intercepting a target window during short low‐level flights, are presented. © 2006 Wiley Periodicals, Inc.
High‐resolution millimeter‐wave radar systems for visualization of unstructured outdoor environments
Authors: Brooker Graham , Hennessey Ross , Bishop Mark , Lobsey Craig , Durrant‐Whyte Hugh , Birch David 
Published: October 2006

AbstractThis paper examines the use of millimeter‐wave radar systems for visualization and navigation in unstructured outdoor environments. Three types of radar systems are described. The first is a long range, 94 GHz, frequency modulated interrupted continuous wave radar which is capable of producing two‐dimensional (2D) reflectivity images to a range of more than 3 km. This is intended for use in long‐range path planning. The second is a class of medium range 77 GHz frequency modulated continuous wave (FMCW) radar with two axis mirror scanners which is capable of producing high resolution threedimensional (3D) imagery out to 500 m at a reasonably slow frame rate. The final class also operates using the FMCW principle, but at 94 GHz, to produce high resolution 2D and 3D images out to about 50 m at a much higher update rate. These shorter range sensors may be used to determine the traversability of the local terrain. The outputs produced by the different classes of radar are examined and the paper considers their advantages when compared to other sensors such as vision and scanning laser. Using radar images, the final section compiles rules for interpreting radar reflectivity images from a path‐planning perspective. © 2006 Wiley Periodicals, Inc.
A framework of sustainable behaviours that can be enabled through the design of neighbourhood‐scale developments
Authors: Williams Katie , Dair Carol 
Published: October 2006

AbstractThe purpose of this paper is to present, and explain, the development of a framework of sustainable behaviours that can, potentially, be enabled through the design of neighbourhood‐scale developments. To be sustainable, such developments need to be technically sustainable (i.e. in terms of materials, construction methods and so on) and to support behavioural sustainability by their residents. This paper focuses on the latter. Drawn from a literature review, the paper presents eight sustainable behaviours that are argued to be enabled by specific design features of neighbourhood developments. These are the following: use less energy in the home; use less water in the home; recycle waste; maintain and encourage biodiversity and ecologically important habitats; make fewer and shorter journeys by fuel inefficient modes of transport; make essential journeys by fuel efficient modes of transport; take part in local community groups, local decision making and local formal and informal social activities and use local services, amenities and businesses. Both theory and empirical evidence underpinning the claimed relationships between the design features and the eight behaviours are presented. The framework, and accompanying explanations, are offered as tools for further research, and as references for practitioners such as urban designers, architects and planners seeking some clarity on designing for behavioural sustainability at the neighbourhood scale. Copyright © 2006 John Wiley & Sons, Ltd and ERP Environment.
Multiple imputation for the comparison of two screening tests in two‐phase Alzheimer studies
Authors: Harel Ofer , Zhou Xiao‐Hua 
Published: October 2006

AbstractTwo‐phase designs are common in epidemiological studies of dementia, and especially in Alzheimer research. In the first phase, all subjects are screened using a common screening test(s), while in the second phase, only a subset of these subjects is tested using a more definitive verification assessment, i.e. golden standard test. When comparing the accuracy of two screening tests in a two‐phase study of dementia, inferences are commonly made using only the verified sample. It is well documented that in that case, there is a risk for bias, called verification bias. When the two screening tests have only two values (e.g. positive and negative) and we are trying to estimate the differences in sensitivities and specificities of the tests, one is actually estimating a confidence interval for differences of binomial proportions. Estimating this difference is not trivial even with complete data. It is well documented that it is a tricky task. In this paper, we suggest ways to apply imputation procedures in order to correct the verification bias. This procedure allows us to use well‐established complete‐data methods to deal with the difficulty of the estimation of the difference of two binomial proportions in addition to dealing with incomplete data. We compare different methods of estimation and evaluate the use of multiple imputation in this case. Our simulation results show that the use of multiple imputation is superior to other commonly used methods. We demonstrate our finding using Alzheimer data. Copyright © 2006 John Wiley & Sons, Ltd.
Cellular and extracellular behavior in the gerbil (Meriones unguiculatus) ventral prostate following different types of castration and the consequences of testosterone replacement
Authors: Oliveira Sérgio Marcelino , Vilamaior Patricia Simone Leite , Corradi Lara Silvia , Góes Rejane Maira , Taboga Sebastião Roberto 
Published: October 2006

AbstractMongolian gerbils (Meriones unguiculatus) were grouped into two experimental groups: GEx.01 suffered orchiectomy and after 30 days received doses of testosterone cipionate (T), while GEx.02 received weekly and alternated doses of the anti‐androgens cyproterone acetate and flutamide for 30 days, and the animals were then euthanized. Structural evaluation reveals a more intense reduction in epithelial height in GEx.02. Smooth muscle cells (SMC) presented a star‐shaped aspect after 30 days of hormonal ablation and basal membrane was shown to be more intensely grooved in GEx.01. In both groups, after hormonal replacement, recovery in epithelial height could be noted and the SMC presented its phenotypes, but an increase in RER was seen, characterizing a modulation from its contractile to secreting phenotype. In conclusion, the prostate presented involution capacity after androgen ablation and the ability to reorganize after hormonal replacement, but events resulting from orchiectomy and subsequent T replacement were shown to be more aggressive to the prostate.
The messaoudensis–trifidum acritarch assemblage and correlation of the base of Ordovician Stage 2 (Floian)
Authors: MOLYNEUX S. G. , RAEVSKAYA E. , SERVAIS T. 
Published: October 2006

The Global Stratotype Section and Point (GSSP) for Stage 2 of the Ordovician System, now the Floian Stage and approximately equivalent to the lower and middle Arenig of England and Wales, is defined by the first appearance datum (FAD) of the graptolite Tetragraptus approximatus in the Diabasbrottet Quarry section at Mount Hunneberg, Sweden. One of the issues this raises is how to correlate the base of Stage 2 at the GSSP with areas and successions that do not contain a correlative graptolite fauna. The distinctive Cymatiogalea messaoudensis–Stelliferidium trifidum acritarch assemblage is present in the upper Tremadocian Araneograptus murrayi Graptolite Biozone of NW England and ranges across the Tremadocian–Stage 2 boundary there (the Tremadoc–Arenig boundary of Anglo-Welsh nomenclature). It also occurs widely at other high southern Ordovician palaeolatitudes around the margin of Gondwana, being reported from Ireland, Wales, the Isle of Man, Belgium, Germany, Spain and Turkey, and may also be present in Bohemia and Argentina (Eastern Cordillera). It therefore has the potential to contribute towards the recognition and correlation of the base of Stage 2 in those areas. Of particular interest are the First Appearance Datums of various taxa within the stratigraphical range of the messaoudensis–trifidum assemblage, notably that of Aureotesta clathrata simplex, which is considered to be close to the base of Stage 2 in NW England.Elements of the messaoudensis–trifidum assemblage also occur in Baltica, the palaeoplate on which the GSSP for the base of Stage 2 is located. However, many of the taxa used to subdivide the messaoudensis–trifidum assemblage around Gondwana have not been recorded from Baltica and may be restricted palaeobiogeographically to the Gondwanan margin. Furthermore, acritarch microfloras have not been reported from the Diabasbrottet Quarry section itself, and there are hiatuses across the base of Stage 2 in the two sections from Baltica considered in this paper. Hence, direct correlation of the base of Stage 2 between the GSSP and other sections using acritarchs is not yet possible. Nevertheless, some taxa, for example the genera Peteinosphaeridium and Rhopaliophora, are shown to have FADs at similar stratigraphical levels in the late Tremadocian Stage of both Baltica and Gondwana, and therefore have the potential to correlate time slices in the late Tremadocian Stage between palaeoplates.
The different origins of stability and change in antisocial personality disorder symptoms
Authors: BURT S. ALEXANDRA , McGUE MATT , CARTER LATANYA A. , IACONO WILLIAM G. 
Published: October 2006

Background. Although adult antisocial personality disorder is generally preceded by a pattern of childhood/adolescent conduct problems, only a subset of those who manifest these developmental precursors go on exhibit significant antisocial behavior in adulthood. To date, however, researchers have yet to resolve the origins of either stability or change in antisocial behavior from childhood/adolescence to adulthood.Method. The present study sought to fill this gap in the literature, making use of a sample of 626 twin pairs from the ongoing Minnesota Twin Family Study (MTFS). Participants were assessed three times between late adolescence and early adulthood. We made use of biometric Cholesky decomposition and latent growth curve modeling techniques, which allow researchers to disambiguate processes of stability and change and evaluate their respective etiologies (i.e. genetic or environmental).Results. Our results revealed that genetic forces were largely responsible for the stability of adult symptoms of antisocial behavior (AAB) from late adolescence through mid-adulthood, while non-shared environmental influences were primarily responsible for change. Importantly, however, although some of the latter represented systematic and long-lasting influence, much of this non-shared environmental variance appeared transient and idiosyncratic.Conclusions. Such findings highlight the enduring impact of genetic influences on AAB, and offer insights into the nature of non-shared environmental influences on development.
A common genetic factor explains the association between psychopathic personality and antisocial behavior
Authors: LARSSON HENRIK , TUVBLAD CATHERINE , RIJSDIJK FRUHLING V. , ANDERSHED HENRIK , GRANN MARTIN , LICHTENSTEIN PAUL 
Published: October 2006

Background. Both psychopathic personality traits and antisocial behavior are influenced by genetic as well as environmental factors. However, little is known about how genetic and environmental factors contribute to the associations between the psychopathic personality traits and antisocial behavior.Method. Data were drawn from a longitudinal population-based twin sample including all 1480 twin pairs born in Sweden between May 1985 and December 1986. The twins responded to mailed self-report questionnaires at two occasions: 1999 (twins 13–14 years old), and 2002 (twins 16–17 years old).Results. A common genetic factor loaded substantially on both psychopathic personality traits and antisocial behavior, whereas a common shared environmental factor loaded exclusively on antisocial behavior.Conclusions. The genetic overlap between psychopathic personality traits and antisocial behavior may reflect a genetic vulnerability to externalizing psychopathology. The finding of shared environmental influences only in antisocial behavior suggests an etiological distinction between psychopathic personality dimensions and antisocial behavior. Knowledge about temperamental correlates to antisocial behavior is important for identification of susceptibility genes, as well as for possible prevention through identification of at-risk children early in life.
Development of a Culture Sub‐population Induction Model: Signaling Pathways Synergy and Taxanes Production by Taxuscanadensis
Authors: Senger Ryan S. , Phisalaphong Muenduen , Karim M. Nazmul , Linden James C. 
Published: October 2006

AbstractCell cultures of Taxus canadensis were subjected to exogenously applied ethylene (ET) hormone and methyl jasmonate (MJ) elicitation in factorial design experiments. Levels of extracellular taxanes, including paclitaxel, were used with principal component analysis for fault detection and real‐coded genetic algorithms for parameter optimization to construct a culture sub‐population induction model. Culture sub‐populations were identified by the model as (1) uninduced, (2) induced to unilateral function of the ET‐signaling pathway, and (3) induced to cooperation between jasmonic acid (JA)‐ and ET‐signaling pathways. Comprehensive model results suggested greater rates of cellular induction (resulting in exogenous taxane production) by ET gas as opposed to MJ elicitation. However, cellular induction of ET‐signaling pathway genes increased the rate of induction of JA‐signaling pathway genes by orders of magnitude. In addition, model results showed that induction of genes leading to extracellular production of the simple taxane 10‐deacetylbaccatin III was regulated by the unilateral ET‐signaling pathway. However, it was suggested that further processing of this simple taxane to complex taxane structures, such as paclitaxel, required further gene induction by the JA‐signaling pathway. Thus, production rate constants of exogenous complex taxanes were predicted to be an order of magnitude lower than that for the simple taxane 10‐deacetylbaccatin III. The fraction of the cell culture sub‐population displaying unilateral ET‐signaling pathway gene induction was found inversely proportional to levels of MJ elicitation. When coupled with simple non‐growth product models, levels of all extracellular taxanes were effectively predicted using the culture sub‐population induction model.