bluuebunny/crossref_metadata_2025_split huggingface dataset:
Contrasting developmental axon regrowth and neurite sprouting of Drosophila mushroom body neurons reveals shared and unique molecular mechanisms
Authors: Marmor‐Kollet Neta , Schuldiner Oren 
Published: June 2015

ABSTRACTThe molecular mechanisms regulating intrinsic axon growth potential during development or following injury remain largely unknown despite their vast importance. Here, we have established a neurite sprouting assay of primary cultured mushroom body (MB) neurons. We used the MARCM technique to both mark and manipulate MB neurons, enabling us to quantify the sprouting abilities of single WT and mutant neurons originating from flies at different developmental stages. Sprouting of dissociated MB neurons was dependent on wnd, the DLK ortholog, a conserved gene that is required for axon regeneration. Next, and as expected, we found that the sprouting ability of adult MB neurons was significantly decreased. In contrast, and to our surprise, we found that pupal‐derived neurons exhibit increased sprouting compared with neurons derived from larvae, suggesting the existence of an elevated growth potential state. We then contrasted the molecular requirements of neurite sprouting to developmental axon regrowth of MB ɣ neurons, a process that we have previously shown requires the nuclear receptor UNF acting via the target of rapamycin (TOR) pathway. Strikingly, we found that while TOR was required for neurite sprouting, UNF was not. In contrast, we found that PTEN inhibits sprouting in adult neurons, suggesting that TOR is regulated by the PI3K/PTEN pathway during sprouting and by UNF during developmental regrowth. Interestingly, the PI3K pathway as well as Wnd were not required for developmental regrowth nor for initial axon outgrowth suggesting that axon growth during circuit formation, remodeling, and regeneration share some molecular components but differ in others. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 76: 262–276, 2016
Environmental factors prevail over dispersal constraints in determining the distribution and assembly of Trichoptera species in mountain lakes
Authors: de Mendoza Guillermo , Ventura Marc , Catalan Jordi 
Published: June 2015

AbstractAiming to elucidate whether large‐scale dispersal factors or environmental species sorting prevail in determining patterns of Trichoptera species composition in mountain lakes, we analyzed the distribution and assembly of the most common Trichoptera (Plectrocnemia laetabilis, Polycentropus flavomaculatus, Drusus rectus, Annitella pyrenaea, and Mystacides azurea) in the mountain lakes of the Pyrenees (Spain, France, Andorra) based on a survey of 82 lakes covering the geographical and environmental extremes of the lake district. Spatial autocorrelation in species composition was determined using Moran's eigenvector maps (MEM). Redundancy analysis (RDA) was applied to explore the influence of MEM variables and in‐lake, and catchment environmental variables on Trichoptera assemblages. Variance partitioning analysis (partial RDA) revealed the fraction of species composition variation that could be attributed uniquely to either environmental variability or MEM variables. Finally, the distribution of individual species was analyzed in relation to specific environmental factors using binomial generalized linear models (GLM). Trichoptera assemblages showed spatial structure. However, the most relevant environmental variables in the RDA (i.e., temperature and woody vegetation in‐lake catchments) were also related with spatial variables (i.e., altitude and longitude). Partial RDA revealed that the fraction of variation in species composition that was uniquely explained by environmental variability was larger than that uniquely explained by MEM variables. GLM results showed that the distribution of species with longitudinal bias is related to specific environmental factors with geographical trend. The environmental dependence found agrees with the particular traits of each species. We conclude that Trichoptera species distribution and composition in the lakes of the Pyrenees are governed predominantly by local environmental factors, rather than by dispersal constraints. For boreal lakes, with similar environmental conditions, a strong role of dispersal capacity has been suggested. Further investigation should address the role of spatial scaling, namely absolute geographical distances constraining dispersal and steepness of environmental gradients at short distances.
Assessing the risk to green sturgeon from application of imidacloprid to control burrowing shrimp in Willapa Bay, Washington—Part I: Exposure characterization
Authors: Frew John A. , Sadilek Martin , Grue Christian E. 
Published: June 2015

Abstract

Willapa Bay and Grays Harbor (WA, USA) comprise the largest region of commercial oyster cultivation on the Pacific Coast. The activities of 2 species of burrowing shrimp impair growth and survival of oysters reared on the intertidal mudflats. To maintain viable harvests, the oyster growers have proposed controlling the shrimp by applying the insecticide imidacloprid onto harvested beds. Green sturgeon (listed in the Endangered Species Act) forage on burrowing shrimp and could be exposed to imidacloprid in the sediment porewater and through consumed prey. Studies were conducted to evaluate the likelihood that green sturgeon would be exposed to imidacloprid and to characterize the subsequent environmental exposure. Comparisons between treated and untreated control beds following test application of the insecticide suggested that green sturgeon fed opportunistically on imidacloprid-impaired shrimp. The highest interpolated imidacloprid residue concentrations in field samples following chemical application were 27.8 µg kg–1 and 31.4 µg kg–1 in porewater and shrimp, respectively. Results from modeled branchial and dietary uptake, based on conservative assumptions, indicated that the porewater exposure route had the greatest contribution to systemic absorption of imidacloprid. The highest average daily uptake from porewater (177.9 µg kg–1 body wt) was 9.5-fold greater than total dietary uptake (18.8 µg kg–1 body wt). Concentrations and durations of exposure would be lower than the levels expected to elicit direct acute or chronic toxic effects. Environ Toxicol Chem 2015;34:2533–2541. © 2015 SETAC
Response of bacteria and meiofauna to iron oxide colloids in sediments of freshwater microcosms
Authors: Höss Sebastian , Frank-Fahle Béatrice , Lueders Tillmann , Traunspurger Walter 
Published: June 2015

Abstract

The use of colloidal iron oxide (FeOx) in the bioremediation of groundwater contamination implies its increasing release into the environment and requires an assessment of its ecotoxicological risk. Therefore, microcosm experiments were carried out to investigate the impact of ferrihydrite colloids on the bacterial and meiofaunal communities of pristine freshwater sediments. The effects of ferrihydrite colloids were compared with those of ferrihydrite macroaggregates to discriminate between colloid-specific and general FeOx impacts. The influence of ferrihydrite colloids on the toxicity of sediment-bound fluoranthene was also considered. At high concentrations (496 mg Fe kg−1 sediment dry wt), ferrihydrite colloids had a significant, but transient impact on bacterial and meiofaunal communities. Although bacterial community composition specifically responded to ferrihydrite colloids, a more general FeOx effect was observed for meiofauna. Bacterial activity responded most sensitively (already at 55 mg Fe kg−1 dry wt) without the potential of recovery. Ferrihydrite colloids did not influence the toxicity of sediment-bound fluoranthene. Significant correlations between bacterial activity and meiofaunal abundances were indicative of trophic interactions between bacteria and meiofauna and therefore of the contribution of indirect food web effects to the observed impacts. The results suggest that the application of ferrihydrite colloids for remediation purposes in the field poses no risk for benthic communities, given that, with the exception of generic bacterial activity, any negative effects on communities were reversible. Environ Toxicol Chem 2015;34:2660–2669. © 2015 SETAC
A third‐order implicit discontinuous Galerkin method based on a Hermite WENO reconstruction for time‐accurate solution of the compressible Navier–Stokes equations
Authors: Xia Yidong , Liu Xiaodong , Luo Hong , Nourgaliev Robert 
Published: June 2015

SummaryA space and time third‐order discontinuous Galerkin method based on a Hermite weighted essentially non‐oscillatory reconstruction is presented for the unsteady compressible Euler and Navier–Stokes equations. At each time step, a lower‐upper symmetric Gauss–Seidel preconditioned generalized minimal residual solver is used to solve the systems of linear equations arising from an explicit first stage, single diagonal coefficient, diagonally implicit Runge–Kutta time integration scheme. The performance of the developed method is assessed through a variety of unsteady flow problems. Numerical results indicate that this method is able to deliver the designed third‐order accuracy of convergence in both space and time, while requiring remarkably less storage than the standard third‐order discontinous Galerkin methods, and less computing time than the lower‐order discontinous Galerkin methods to achieve the same level of temporal accuracy for computing unsteady flow problems. Copyright © 2015 John Wiley & Sons, Ltd.
Augmenting the immersed boundary method with Radial Basis Functions (RBFs) for the modeling of platelets in hemodynamic flows
Authors: Shankar Varun , Wright Grady B. , Kirby Robert M. , Fogelson Aaron L. 
Published: June 2015

SummaryWe present a new computational method by extending the immersed boundary (IB) method with a geometric model based on parametric radial basis function (RBF) interpolation of the Lagrangian structures. Our specific motivation is the modeling of platelets in hemodynamic flows, although we anticipate that our method will be useful in other applications involving surface elasticity. The efficacy of our new RBF‐IB method is shown through a series of numerical experiments. Specifically, we test the convergence of our method and compare our method with the traditional IB method in terms of computational cost, maximum stable time‐step size, and volume loss. We conclude that the RBF‐IB method has advantages over the traditional IB method and is well‐suited for modeling of platelets in hemodynamic flows. Copyright © 2015 John Wiley & Sons, Ltd.
TBM performance and disc cutter wear prediction based on ten years experience of TBM tunnelling in Iran
Authors: Hassanpour Jafar , Rostami Jamal , Zhao Jian , Azali Sadegh Tarigh 
Published: June 2015

AbstractAccurate estimation of rate of penetration (ROP), daily rate of advance (AR), and cutter cost/life is necessary for the justification and successful use of a TBM on any tunneling project. Various models have been introduced over the years to provide such estimates. In many cases, these models have been successful with pin point accuracy, and in other instances off by a wide margin. Improving the accuracy of performance prediction models for hard rock TBMs has been the subject of many studies, some yielding project‐based models and some more universal models that can be used elsewhere. This paper will discuss the latest version of a new empirical model for estimating penetration rate and disc cutter life for hard rock TBM tunneling based on recent tunneling projects, constructed during the period 2002–2009. The new model was then applied to predict TBM performance and disc cutter wear in different mechanized tunneling projects under construction since 2009. Accuracy and validity of the model for prediction of ROP were checked by comparing predicted and measured values of TBM performance in 24 km of newly bored tunnel. The results indicate that despite some minor deviations in estimates in some tunnel sections, reasonable agreement can be observed between predicted and actual ROP of TBMs.
Darstellung von Wasserdrücken im Boden mit strömendem Grundwasser
Authors: Goldscheider Michael 
Published: June 2015

AbstractAusgehend vom Netz der Strom‐ und Äquipotentiallinien einer Grundwasserströmung wird für verschiedene Fälle der Zusammenhang zwischen den auf ein Volumenelement des Bodens wirkenden Wasserdruckkräften und den von diesen Kräften abgeleiteten Größen Auftriebskraft und Strömungskraft nach Terzaghi dargestellt. Die Strömungskraft erweist sich dabei als diejenige Kraft, die zu der im Falle von ruhendem Grundwasser wirkenden Auftriebskraft in Strömungsrichtung vektoriell hinzugefügt werden muss, um die bei Durchströmung wirkende resultierende Wasserdruckkraft zu erhalten. Es wird gezeigt, wie sich die effektive resultierende Volumenkraft eines Bodenkörpers, die für die effektiven Spannungen bestimmend ist, nach diesen beiden statisch äquivalenten Konzepten ergibt. Als Beispiel werden die Bedingungen für einen hydraulischen Grundbruch betrachtet.Representation of water pressures in the soil with flowing ground water. Based on a groundwater flow net consisting of flow lines and equipotential lines, the relations between the pore water pressure forces acting on a volume element of the soil and the deduced uplift and seepage forces after Terzaghi are depicted for different cases. The seepage force turns out to be the force that has to be added as a vector in the flow direction to the uplift force acting in case of stagnant groundwater to obtain the resultant water pressure force in case of flowing groundwater. It is depicted how the effective resultant volume force of a soil body, which is determinant for the effective stresses, arises by the two statically equivalent concepts. As an example, the conditions of seepage failure are considered.
Innerstädtischer Tunnelbau – Herausforderungen des Spezialtiefbaus am Beispiel der S‐Bahnlinie S21 in Berlin
Authors: Quick Hubert , Meißner Simon , Hippe Simon , Fahlbusch Dietrich , Jaeger Arno 
Published: June 2015

AbstractDas Projekt S21 stellt eines der wichtigsten infrastrukturellen Bauprojekte in Berlin da. Aufgrund der bereits vorhanden unter‐ und oberirdischen Bebauung nördlich des Bahnhofs und der geplanten städtebaulichen Entwicklung ergeben sich für die Teilbaugruben des Projekts S21 unterschiedlichste Randbedingungen. Insbesondere die Nähe zu den unterirdischen baulichen Anlagen der Fern‐ und U‐Bahn sowie die Nutzung der B96 und der Invalidenstraße während der Bauausführung stellen besondere ingenieurtechnische Herausforderungen dar. In diesem Bericht werden die daraus resultierenden Baugruben‐ und Abdichtungssysteme aufgezeigt und insbesondere die Herausforderungen des Tunnelbereichs mit Überbauung unter anderem durch das Hochhaus MK8 beleuchtet. Die vielfältigen technischen und formellen Anforderungen eines komplexen innerstädtischen Tunnelbauvorhabens werden aus Sicht der Prüfer für das Eisenbahn‐Bundesamt dargestellt.Tunnelling in urban area – Challenging demands on the geotechnical construction using the example of the S21 railway project in Berlin. The S21 railway project is one of the most important infrastructural projects in Berlin. With existing structures above and below ground plus further urban developments in the pipeline, the result is highly diverse boundary conditions for the numerous excavations needed for this project. In particular, the proximity to underground structures for long‐distance and metro lines as well as the B96 trunk road and Invalidenstrasse, which have to remain open during construction, place high demands on the engineering. This report describes the ensuing shoring and waterproofing systems for the excavations and, in particular, the challenges posed by tunnels beneath buildings, including the high‐rise building MK8. The various technical and procedural requirements of a complex urban tunnelling project are presented from the perspective of the checking engineers appointed by Germany's Federal Railway Authority.
Older people experiencing homelessness show marked impairment on tests of frontal lobe function
Authors: Rogoz Astrid , Burke David 
Published: June 2015

ObjectiveReported rates of mild and moderate cognitive impairment in older people experiencing homelessness range from 5–80%. The objective of this study was to determine the prevalence and characteristics of cognitive impairment in older people experiencing homelessness in the inner city of Sydney, Australia.MethodMen and women experiencing homelessness aged 45 years and over in the inner city were screened for cognitive impairment. Participants who scored 26 or below on the mini‐mental state examination and/or were impaired on any one of the clock‐drawing test, the verbal fluency test and the trail‐making test, part B were then assessed with a semi‐structured interview, including the 21‐item Depression Anxiety Stress Scale and the 12‐item General Health Questionnaire.ResultsScreening of 144 men and 27 women aged between 45 years and 93 years identified cognitive impairment in 78%. Subsequently, high rates of mental and physical illness were identified, and 75% of subjects who were cognitively impaired performed poorly on frontal lobe tests. The trail‐making test, part B was the most sensitive measure of frontal function.ConclusionsThis study demonstrated that a large majority of older people experiencing homelessness, in the inner city of a high‐income country, showed impairment on tests of frontal lobe function, a finding that could have significant implications for any medical or psychosocial intervention. Copyright © 2015 John Wiley & Sons, Ltd.
Automated iterative reclustering framework for determining hierarchical functional networks in resting state fMRI
Authors: Shams Seyed‐Mohammad , Afshin‐Pour Babak , Soltanian‐Zadeh Hamid , Hossein‐Zadeh Gholam‐Ali , Strother Stephen C. 
Published: June 2015

AbstractTo spatially cluster resting state‐functional magnetic resonance imaging (rs‐fMRI) data into potential networks, there are only a few general approaches that determine the number of networks/clusters, despite a wide variety of techniques proposed for clustering. For individual subjects, extraction of a large number of spatially disjoint clusters results in multiple small networks that are spatio‐temporally homogeneous but irreproducible across subjects. Alternatively, extraction of a small number of clusters creates spatially large networks that are temporally heterogeneous but spatially reproducible across subjects. We propose a fully automatic, iterative reclustering framework in which a small number of spatially large, heterogeneous networks are initially extracted to maximize spatial reproducibility. Subsequently, the large networks are iteratively subdivided to create spatially reproducible subnetworks until the overall within‐network homogeneity does not increase substantially. The proposed approach discovers a rich network hierarchy in the brain while simultaneously optimizing spatial reproducibility of networks across subjects and individual network homogeneity. We also propose a novel metric to measure the connectivity of brain regions, and in a simulation study show that our connectivity metric and framework perform well in the face of low signal to noise and initial segmentation errors. Experimental results generated using real fMRI data show that the proposed metric improves stability of network clusters across subjects, and generates a meaningful pattern for spatially hierarchical structure of the brain. Hum Brain Mapp 36:3303–3322, 2015. © 2015 Wiley Periodicals, Inc.
Upregulation of CD200 is associated with regulatory T cell expansion and disease progression in multiple myeloma
Authors: Aref Salah , Azmy Emaad , El‐Gilany Abdel Hady 
Published: June 2015

AbstractImmune dysfunction is an important feature of multiple myeloma (MM) leading to infections, enhancement of tumour growth and resistance to chemotherapy. The overexpression of CD200, expansion of T regulatory (Treg) cell and increased levels of immune modulatory cytokines like IL10, IL6 and transforming growth factor beta (TGFβ) were suggested to have a role in this context. The aim of this study was to assess CD200 expression, Treg percentage by flow cytometry and immune modulatory cytokines (IL10, IL6, TGFβ) by enzyme‐linked immunosorbent assay in MM patients at diagnosis. This study included 50 MM patients at diagnosis and 20 healthy controls. The positive CD200 expression was detected in 72% of MM patients. Among the CD200 positive group, 4/13 patients (30.8%) were classified as stage I, 18/23 (78.3%) were in stage II and 14/14 (100%) were in stage III; according to International scoring system. Treg percentage was significantly higher in stage III, followed by stage II then stage I (p < 0.01). Serum IL6, IL10 and TGFβ were significantly higher in MM patients as compared with controls (p < 0.01, p < 0.01, p < 0.05, respectively). The increased expression of CD200 and Treg percentages was associated with increased severity biomarkers (serum LDH and β2 microglobulin). The degree of CD200 expression was significantly positively correlated to Treg percentage (r = 0.565, p < 0.01). Analysis of the CD200 negative patients had a better progression free survival (p = 0.032) and overall survival (p = 0.04) as compared with those positive for CD200 expression. These findings illustrate a clear correlation between myeloma cell CD200 expression level and the frequency of immunosuppressive Treg cells. In conclusion, increased expression of CD200, expansion of suppressive Treg cells and elevation of cytokines might have a role in MM progression in this cohort of patients. Copyright © 2015 John Wiley & Sons, Ltd.
A functional approach for research on cognitive control: Analysing cognitive control tasks and their effects in terms of operant conditioning
Authors: Liefooghe Baptist , De Houwer Jan 
Published: June 2015

AbstractCognitive control is an important mental ability that is examined using a multitude of cognitive control tasks and effects. The present paper presents the first steps in the elaboration of a functional approach, which aims to uncover the communalities and differences between different cognitive control tasks and their effects. Based on the idea that responses in cognitive control tasks qualify as operant behaviour, we propose to reinterpret cognitive control tasks in terms of operant contingencies and cognitive control effects as instances of moderated stimulus control. We illustrate how our approach can be used to uncover communalities between topographically different cognitive control tasks and can lead to novel questions about the processes underlying cognitive control.