bluuebunny/crossref_metadata_2025_split huggingface dataset:
Anticipatory postural adjustments prior to step initiation are hypometric in untreated Parkinson’s disease: an accelerometer‐based approach
Authors: Mancini M. , Zampieri C. , Carlson‐Kuhta P. , Chiari L. , Horak F. B. 
Published: April 2009

Background and purpose:  Anticipatory postural adjustments (APAs), prior to step initiation, are bradykinetic in advanced Parkinson’s disease (PD) and may be one of the factors associated with ‘start hesitation’. However, little is known about APAs in the early stage of PD. In this study, we determined whether body‐worn accelerometers could be used to characterize step initiation deficits in subjects with early‐to‐moderate, untreated PD.Methods:  Eleven PD and 12 healthy control subjects were asked to take two steps. Postural adjustments were compared from center of pressure (COP) and from acceleration of the trunk at the center of mass level (L5).Results:  Our findings show that APAs measured from the peak COP displacement toward the swing leg and the peak trunk acceleration toward the stance leg were smaller in untreated PD compared with control subjects. The magnitude of APAs measured from peak COP displacements and accelerations were correlated.Conclusion:  These results suggest that quantitative analysis of step initiation from one accelerometer on the trunk could provide useful information for the characterization of patients in early stages of PD, when clinical evidence of start hesitation may not be detectable. Ambulatory monitoring of step initiation is also promising for monitoring patient progression in the home environment, and eventually providing feedback for preventing freezing of gait episodes.
Abnormal spatial asymmetry of selective attention in ADHD
Authors: Chan Edgar , Mattingley Jason B , Huang‐Pollock Cynthia , English Therese , Hester Robert , Vance Alasdair , Bellgrove Mark A. 
Published: April 2009

Background:  Evidence for a selective attention abnormality in children with attention deficit hyperactivity disorder (ADHD) has been hard to identify using conventional methods from cognitive science. This study tested whether the presence of selective attention abnormalities in ADHD may vary as a function of perceptual load and target lateralisation. Given evidence of right‐hemisphere dysfunction in ADHD we predicted increased interference effects for right, but not left‐sided target displays, particularly under low perceptual load.Method:  Fourteen children with ADHD‐C and 14 typically developing children were tested on a modified flanker task under low and high perceptual load. We also sought evidence for our hypothesis in a re‐analysis of an independent data set (42 ADHD; 34 typically developing) in which load effects on selective attention in ADHD were previously examined (Huang‐Pollock, Nigg, & Carr, 2005).Results:  As predicted, all children showed evidence of greater interference by flankers under low compared with high perceptual load conditions. Crucially, however, children with ADHD showed the greatest interference effect for right‐sided target displays under low but not high perceptual load. In contrast, typically developing children showed the greatest interference for left‐sided target displays. The magnitude of interference for right‐sided targets was also positively correlated with ADHD symptom levels. Re‐analysis of an independent data set (Huang‐Pollock et al., 2005) further confirmed our findings.Conclusions:  This study demonstrates that interference effects in children with ADHD and typically developing children are spatially asymmetrical but opposite in direction. The pattern of right‐sided interference effects in children with ADHD suggests disruption within right hemisphere attentional networks in ADHD.
Sexual selection is not the origin of long necks in giraffes
Authors: Mitchell G. , Van Sittert S. J. , Skinner J. D. 
Published: April 2009

AbstractThe evolutionary origin of the long neck of giraffes is enigmatic. One theory (the ‘sexual selection’ theory) is that their shape evolved because males use their necks and heads to achieve sexual dominance. Support for this theory would be that males invest more in neck and head growth than do females. We have investigated this hypothesis in 17 male and 21 female giraffes with body masses ranging from juvenile to mature animals, by measuring head mass, neck mass, neck and leg length and the neck length to leg length ratio. We found no significant differences in any of these dimensions between males and females of the same mass, although mature males, whose body mass is significantly (50%) greater than that of mature females, do have significantly heavier (but not longer) necks and heavier heads than mature females. We conclude that morphological differences between males and females are minimal, that differences that do exist can be accounted for by the larger final mass of males and that sexual selection is not the origin of a long neck in giraffes.
Early onset myoclonic epilepsy and 15q26 microdeletion: Observation of the first case
Authors: Veredice Chiara , Bianco Flaviana , Contaldo Ilaria , Orteschi Daniela , Stefanini Maria Chiara , Battaglia Domenica , Lettori Donatella , Guzzetta Francesco , Zollino Marcella 
Published: April 2009

SummaryThe authors report the study of a 30‐month‐old girl with refractory myoclonic epilepsy associated with mental retardation, growth delay, peculiar facial appearance, and minor physical anomalies. Extensive genetic studies were performed, including an array‐based comparative genomic hybridization (array‐CGH) that showed a cryptic interstitial deletion of 15q (5 Mb) affecting the 15q26.1–26.2 region. Partial deletions of the long arm of chromosome 15, including the 15q26 region, were observed in syndromic associations that typically include congenital diaphragmatic hernia, but neurologic features were poorly described and epileptic seizures were never reported. Our findings suggest that genes for seizures could be included in the 15q26.1q26.2 deletion interval.
Excitatory effects of gap junction blockers on cerebral cortex seizure‐like activity in rats and mice
Authors: Voss Logan J. , Jacobson Gregory , Sleigh James W. , Steyn‐Ross Alistair , Steyn‐Ross Moira 
Published: April 2009

SummaryPurpose:  The role of gap junctions in seizures is an area of intense research. Many groups have reported anticonvulsant effects of gap junction blockade, strengthening the case for a role for gap junctions in ictogenesis. The cerebral cortex is underrepresented in this body of research. We have investigated the effect of gap junction blockade on seizure‐like activity in rat and mouse cerebral cortex slices.Methods:  Seizure‐like activity was induced by perfusing with low‐magnesium artificial cerebrospinal fluid. The effect of three gap junction blockers was investigated in rat cortical slices; quinine (200 and 400 μm), quinidine (100 and 200 μm), and carbenoxolone (100 and 200 μm). In addition, the effect of mefloquine was investigated in wild‐type mice and connexin36 knockout mice. The data were analyzed for the effect on frequency and amplitude of seizure‐like events.Results:  Paradoxical excitatory effects on seizure‐like activity were observed for all three agents in rat cortical slices. Quinine (200 μm) and carbenoxolone (100 μm) increased both the frequency and amplitude of seizure‐like events. Quinidine (100 μm) increased the frequency of events. Higher doses of quinine (400 μm) and carbenoxolone (200 μm) had biphasic excitatory–inhibitory effects. Similar excitatory effects were observed in adult wild‐type mouse cortical slices perfused with mefloquine (5 μm or 10 μm), but were absent in slices from connexin36‐deficient mice.Discussion:  In conclusion, we have shown a paradoxical proseizure effect of pharmacologic gap junction blockade in a cortical model of seizure‐like activity. We suggest that this effect is probably due to a disruption of inhibitory interneuron coupling secondary to connexin36 blockade.
Exploring the Synergy Between Industrial Ecology and System of Systems to Understand Complexity
Authors: DeLaurentis Daniel A. , Ayyalasomayajula Sricharan 
Published: April 2009

SummaryTwo objectives are pursued in this article. First, from a methodological perspective, we explore the relationships among the constructs of complex adaptive systems, systems of systems, and industrial ecology. Through examination of central traits of each, we find that industrial ecology and system of systems present complementary frameworks for posing systemic problems in the context of sociotechnical applications. Furthermore, we contend that complexity science (the basis for the study of complex adaptive systems) provides a natural and necessary foundation and set of tools to analyze mechanisms such as evolution, emergence, and regulation in these applications. The second objective of the article is to illustrate the use of two tools from complexity sciences to address a network transition problem in air transportation framed from the system‐of‐systems viewpoint and shaped by an industrial ecology perspective. A stochastic simulation consisting of network theory analysis combined with agent‐based modeling to study the evolution of an air transport network is presented. Patterns in agent behavior that lead to preferred outcomes across two scenarios are observed, and the implications of these results for decision makers are described. Furthermore, we highlight the necessity for future efforts to combine the merits of both system of systems and industrial ecology in tackling the issues of complexity in such large‐scale, sociotechnical problems.
Integration of Life Cycle Assessment Into Agent‐Based Modeling
Authors: Davis Chris , Nikolić Igor , Dijkema Gerard P. J. 
Published: April 2009

SummaryA method is presented that allows for a life cycle assessment (LCA) to provide environmental information on an energy infrastructure system while it evolves. Energy conversion facilities are represented in an agent‐based model (ABM) as distinct instances of technologies with owners capable of making decisions based on economic and environmental information. This simulation setup allows us to explore the dynamics of assembly, disassembly, and use of these systems, which typically span decades, and to analyze the effect of using LCA information in decision making.We were able to integrate a simplified LCA into an ABM by aligning and connecting the data structures that represent the energy infrastructure and the supply chains from source to sink. By using an appropriate database containing life cycle inventory (LCI) information and by solving the scaling factors for the technology matrix, we computed the contribution to global warming in terms of carbon dioxide (CO2) equivalents in the form of a single impact indicator for each instance of technology at each discrete simulation step. These LCAs may then serve to show each agent the impact of its activities at a global level, as indicated by its contribution to climate change. Similar to economic indicators, the LCA indicators may be fed back to the simulated decision making in the ABM to emulate the use of environmental information while the system evolves. A proof of concept was developed that is illustrated for a simplified LCA and ABM used to generate and simulate the evolution of a bioelectricity infrastructure system.
Differing Expansion Contributions of Three Investment Materials Used for Casting Titanium
Authors: Low Danny 
Published: April 2009

Abstract Purpose: This laboratory study aimed at investigating the effect of setting expansion (SE), which could enlarge a wax pattern by concurrent exothermic reaction. Materials and Methods: Two phosphate‐bonded investment materials (Rematitan Plus, T‐invest C & B) and alumina‐magnesia‐based investment material (Titavest CB) were subjected to setting temperature and SE measurements (n = 10). Full‐crown wax patterns were prepared from metal dies having the same design. Crown castings (n = 6) were made using a one‐chamber high‐pressure casting machine. Commercially pure titanium ingot (Japanese Industrial Standard Class II) was used for each casting. Dimensional accuracy of the cast crowns was expressed by marginal discrepancy for a pair of wax pattern and casting prepared from the same die. All results were then subjected to regression analysis. Results: Rematitan Plus gave the highest setting temperature (about 70°C) and the highest SE (1.16 ± 0.01%) almost concurrently. The result was that Rematitan Plus produced oversized crowns from the lowest thermal expansion (TE) value (0.53 ± 0.05%) reducing the linear correlation to 0.80 (p < 0.05). No significant linear relationship was found between SE of investment material and crown‐casting accuracy. Conclusions: The almost concurrent occurrence of high SE and high setting temperature generation in Rematitan Plus enlarged the wax pattern and effectively supplemented its low TE to produce oversized crowns. Despite this adverse effect, the correlation between TE and crown accuracy was still high. It is generally expected that the TE values given by manufacturers predict crown accuracy, when uniform TE, small SE, and minimum heat generation during setting are assured.
Waste lipids to energy: how to optimize methane production from long‐chain fatty acids (LCFA)
Authors: Alves M. Madalena , Pereira M. Alcina , Sousa Diana Z. , Cavaleiro Ana J. , Picavet Merijn , Smidt Hauke , Stams Alfons J. M. 
Published: April 2009

SummaryThe position of high‐rate anaerobic technology (HR‐AnWT) in the wastewater treatment and bioenergy market can be enhanced if the range of suitable substrates is expanded. Analyzing existing technologies, applications and problems, it is clear that, until now, wastewaters with high lipids content are not effectively treated by HR‐AnWT. Nevertheless, waste lipids are ideal potential substrates for biogas production, since theoretically more methane can be produced, when compared with proteins or carbohydrates. In this minireview, the classical problems of lipids methanization in anaerobic processes are discussed and new concepts to enhance lipids degradation are presented. Reactors operation, feeding strategies and prospects of technological developments for wastewater treatment are discussed. Long‐chain fatty acids (LCFA) degradation is accomplished by syntrophic communities of anaerobic bacteria and methanogenic archaea. For optimal performance these syntrophic communities need to be clustered in compact aggregates, which is often difficult to achieve with wastewaters that contain fats and lipids. Driving the methane production from lipids/LCFA at industrial scale without risk of overloading and inhibition is still a challenge that has the potential for filling a gap in the existing processes and technologies for biological methane production associated to waste and wastewater treatment.
The expression of recombinant genes in Escherichia coli can be strongly stimulated at the transcript production level by mutating the DNA‐region corresponding to the 5′‐untranslated part of mRNA
Authors: Berg Laila , Lale Rahmi , Bakke Ingrid , Burroughs Nigel , Valla Svein 
Published: April 2009

SummarySecondary structures and the short Shine–Dalgarno sequence in the 5′‐untranslated region of bacterial mRNAs (UTR) are known to affect gene expression at the level of translation. Here we report the use of random combinatorial DNA sequence libraries to study UTR function, applying the strong, σ32/σ38‐dependent, and positively regulated Pm promoter as a model. All mutations in the libraries are located at least 8 bp downstream of the transcriptional start site. The libraries were screened using the ampicillin‐resistance gene (bla) as reporter, allowing easy identification of UTR mutants that display high levels of expression (up to 20‐fold increase relative to the wild‐type at the protein level). Studies of the two UTR mutants identified by a modified screening procedure showed that their expression is stimulated to a similar extent at both the transcript and protein product levels. For one such mutant a model analysis of the transcription kinetics showed significant evidence of a difference in the transcription rate (about 18‐fold higher than the wild type), while there was no evidence of a difference in transcript stability. The two UTR sequences also stimulated expression from a constitutive σ70‐dependent promoter (P1/Panti‐tet), demonstrating that the UTR at the DNA or RNA level has a hitherto unrecognized role in transcription.
Bacterial responses and interactions with plants during rhizoremediation
Authors: Segura Ana , Rodríguez‐Conde Sara , Ramos Cayo , Ramos Juan L. 
Published: April 2009

SummaryWith the increase in quality of life standards and the awareness of environmental issues, the remediation of polluted sites has become a priority for society. Because of the high economic cost of physico‐chemical strategies for remediation, the use of biological tools for cleaning‐up contaminated sites is a very attractive option. Rhizoremediation, the use of rhizospheric microorganisms in the bioremediation of contaminants, is the biotechnological approach that we explore in this minireview. We focus our attention on bacterial interactions with the plant surface, responses towards root exudates, and how plants and microbes communicate. We analyse certain strategies that may improve rhizoremediation, including the utilization of endophytes, and finally we discuss several rhizoremediation strategies that have opened ways to improve biodegradation.
Virulence regulation in Citrobacter rodentium: the art of timing
Authors: Yang Ji , Tauschek Marija , Hart Emily , Hartland Elizabeth L. , Robins‐Browne Roy M. 
Published: April 2009

SummaryThe mouse enteric pathogen Citrobacter rodentium, like its human counterpart, enteropathogenic Escherichia coli, causes attaching and effacing lesions in the intestinal epithelium of its host. This phenotype requires virulence factors encoded by the locus for enterocyte effacement (LEE) pathogenicity island. For timely expression of these virulence determinants at the site of infection and for efficient delivery of some virulence factors into epithelial cells, C. rodentium utilizes a positive regulatory loop involving the LEE‐encoded regulatory proteins Ler, GrlA and GrlR to control LEE expression. Several transcription factors not encoded by LEE, some of which respond to specific environmental signals, also participate in this regulatory loop. Recently, we identified a non‐LEE encoded, AraC‐like regulatory protein, RegA, which plays a key role in the ability of C. rodentium to colonize the intestine. RegA functions by activating the transcription of a number of horizontally acquired operons encoding virulence‐associated factors, such as autotransporters, fimbriae, a dispersin‐like protein and its transporter. In addition, RegA represses transcription of a number of housekeeping genes. Importantly, RegA requires a gut‐specific environmental signal, bicarbonate, to exert its effects on gene expression. In our proposed model, when C. rodentium senses bicarbonate ions in the gastrointestinal tract, RegA directs the bacterium to reduce the production of proteins involved in normal cellular functions, while enhancing the production of factors required for colonization and virulence.
Mapping cumulative human impacts to California Current marine ecosystems
Authors: Halpern Benjamin S. , Kappel Carrie V. , Selkoe Kimberly A. , Micheli Fiorenza , Ebert Colin M. , Kontgis Caitlin , Crain Caitlin M. , Martone Rebecca G. , Shearer Christine , Teck Sarah J. 
Published: April 2009

AbstractQuantitative assessment of the spatial patterns of all human uses of the oceans and their cumulative effects is needed for implementing ecosystem‐based management, marine protected areas, and ocean zoning. Here, we apply methods developed to map cumulative impacts globally to the California Current using more comprehensive and higher‐quality data for 25 human activities and 19 marine ecosystems. This analysis indicates where protection and threat mitigation are most needed in the California Current and reveals that coastal ecosystems near high human population density and the continental shelves off Oregon and Washington are the most heavily impacted, climate change is the top threat, and impacts from multiple threats are ubiquitous. Remarkably, these results were highly spatially correlated with the global results for this region (R2= 0.92), suggesting that the global model provides guidance to areas without local data or resources to conduct similar regional‐scale analyses.
Comparison between manual and automated total nucleated cell counts using the ADVIA 120 for pleural and peritoneal fluid samples from dogs, cats, horses, and alpacas
Authors: Gorman M. Elena , Villarroel Aurora , Tornquist Susan J. , Flachsbart Joy , Warden Annette , Boeder Lisa 
Published: April 2009

Background: Analysis of body fluids includes an estimate of total nucleated cell count (TNCC). Automated methods may enhance the accuracy and timeliness of TNCC results.Objective: The purpose of this report was to assess the ability of the ADVIA 120 hematology analyzer to accurately count nucleated cells in pleural and peritoneal fluids from animals, compared with manual counts.Methods: Pleural and peritoneal fluids submitted in EDTA tubes to our laboratory over a 17‐month period were used in the study. TNCC/μL was determined by a manual method, using a hemocytometer, and by an automated method, using the ADVIA 120. Correlation of results was determined by Passing‐Bablok regression, Bland–Altman plots, and Pearson correlation analysis.Results: Samples from dogs (n=36), cats (n=36), horses (n=59), and alpacas (n=11) were analyzed. High correlation in TNCC between methods was found for peritoneal fluid (n=93, r=.959), pleural fluid (n=49, r=.966), and all fluids combined (n=142, r=.960) (P<.001). Variation between methods was greater in samples with TNCCs<1000/μL (r=.62, P<.001). The ADVIA systematically overestimated the number of cells in all fluid samples by 95 cells/μL (confidence interval=19.2–190.5/μL).Conclusion: The ADVIA 120 reliably determines TNCC in pleural and peritoneal effusions and can be recommended for routine veterinary laboratory analysis.