bluuebunny/crossref_metadata_2025_split huggingface dataset:
Environmental variables affecting small‐scale distributions of five rotifer species in Lancaster Lake, Michigan
Authors: Fairchild G. Winfield , Stemberger Richard S. , Epskamp Lawrence C. , Debaugh Henry A. 
Published: January 2012

AbstractThe small‐scale distributions of the rotifers Polyarthra vulgaris, Synchaeta stylata, Conochilus unicornis, Hexarthra mira, and Asplanchna priodonta were investigated in Lancaster Lake, Cheboygan County, Michigan, July 21, 1974. Measurements were taken for 13 depths (at 1‐m intervals) and at 4 times of the day (1:00 AM, 7:00 AM, 1:00 PM, and 7:00 PM). In addition, the abundances of 6 crustacean, 2 planktonic dipteran, and 10 algal species, as well as temperature, light, oxygen, chlorophyll a, alkalinity, pH and free carbon dioxide were measured. Whereas abiotic factors appeared to control large scale occupation of the lake, and excluded most species from the deeper portions of the hypolimnion, small‐scale distributional variation of the rotifers depended upon biotic interactions, particularly with the crustacean zooplankton.
Typologie de bactéries prélevées devant le delta du Rhǒne. Utilisation d'une méthode objective: L'analyse des correspondances
Authors: Berland Brigitte R. , Bonin Daniel J. , Durbec Jean‐Pierre , Maestrini Serge Y. 
Published: January 2012

AbstractBacteria isolated from surface sea waters, brackish waters and from algal cultures were classified in nutritional clusters. Results obtained with an hierarchical method were improved by using the correspondence analysis. The former main statements appear confirmed and new informations are pointed out, mainly concerning the organic compounds which are the best indexes of the nutritional characteristics; e. g. a few organic acids and amino‐acids can be used to estimate the versatility of bacteria; it also appears that strains which preferentially assimilate substrates of one chemical group, do not easily attack substances of other groups.
Phycoerythrin in the deeper water layer of a stratified eutrophic lake: An application of bile pigment in determining the standing crop of blue‐green algae
Authors: Watanabe Mariyo F. 
Published: January 2012

AbstractAbsorption spectra of intact phytoplankton cells collected from a stratified eutrophic lake in Japan were studied.Vertical and seasonal changes in the content of phycoerythrin of blue‐green algae were indicated on the basis of the absorbance at 560 nm in those spectra. The possibility of an application of the technique to estimate the standing crop of blue‐green algae in the phytoplankton community was discussed.
Three new species of gnathostomulida from the West Atlantic
Authors: Farris Richard A. 
Published: January 2012

AbstractTwo new species of Gnathostomulida from Bermuda and one from North Carolina are described. All belong to the higher Bursovaginoidae with two occurring in the genus Austrognathia and one in the genus Gnathostomula. Tables of major diagnostic characters showing morphological variability within species and between previously described species in the same genus are included. Clarification in recognition of Gnathostomula jenneri and Gnathostomula brunidens is given under “Remarks on Known Species”.
Winter anoxia — a general feature of ponds in cold temperate regions
Authors: Nagell B. , Brittain J. E. 
Published: January 2012

AbstractThere are good reasons to believe that in cold temperate regions the whole water masses of ponds with little or no through flow are anoxic during the winter. This feature, demonstrated for Scandinavian ponds of widely differing productivity, must be of great ecological significance for the pond fauna.
Comparative morphology of the gas bladder in driftwood catfishes (Siluriformes: Auchenipteridae)
Authors: Birindelli José L. O. , Akama Alberto , Britski Heraldo A. 
Published: January 2012

AbstractThe gross morphology of the gas bladder is described and illustrated for representatives of most species and all valid genera of the Auchenipteridae (Siluriformes). Although, a simple cordiform gas bladder is present in some species of the family, others are characterized by their distinctive gas‐bladder shape and diverticula disposition. An acute posterior end of the gas bladder characterizes Centromochlus heckelii and C. macracanthus, and is variably present in specimens of Auchenipterus. Tocantinsia piresi and Asterophysus batrachus have distinctive gas bladders differing in number of diverticula (two or many). The two species of Trachycorystes are diagnosed based on their gas bladder morphology: T. menezesi has a simple cordiform bladder, whereas T. trachycorystes has a pair of lateral diverticulum and, usually, a well‐developed terminal diverticulum. Species of Auchenipterichthys are characterized by having a secondary bladder with simple chamber. Short or elongate and divergent terminal diverticula are exclusive to most cis‐andine species of Trachelyopterus. Tetranematichthys and trans‐andine species of Trachelyopterus share a well‐developed secondary chamber or terminal diverticula ventrally or dorsally connected to the posterior chambers. The small‐sized species of Ageneiosus have well‐developed gas bladders with a pair of posterior diverticula, whereas large‐sized species have a reduced gas bladder with tunica externa varying from non‐, partially, or completely ossified. Eight phylogenetic characters are proposed based on the morphology of the gas bladder and associated structures in species of Auchenipteridae, and the evolution of those characters in the family discussed. J. Morphol., 2012. © 2012 Wiley Periodicals, Inc.
Tissue remodeling gene expression in a murine model of chronic rhinosinusitis
Authors: Sautter Nathan B. , Delaney Katherine L. , Hausman Frances A. , Trune Dennis R. 
Published: January 2012

AbstractObjective/Hypothesis:The matrix metalloproteinase (MMP), fibroblast growth factor (FGF), and bone morphogenetic protein (BMP) families regulate tissue remodeling in many normal and pathophysiologic processes. We hypothesize that induction of chronic sinonasal inflammation will be associated with changes in regulation of these tissue remodeling cytokines.Methods:Balb/c mice aged 8 to 12 weeks were sensitized and treated with intranasal Aspergillus fumigatis (AF) three times per week for 1 week, 3 weeks, 2 months, and 3 months (n = 8 each time point). Sinonasal tissues were evaluated for changes in MMP, FGF, and BMP regulation using standard RT‐PCR techniques. Additional snouts were processed for histology and immunohistochemistry. Untreated mouse snouts of identical age were used as controls.Results:Significant upregulation of MMP8 was observed at 2 months, and MMP1a, MMP7, MMP8, and MMP12 were all significantly upregulated at 3 months. FGF3 was significantly upregulated at 3 weeks and 3 months, and FGF5, FGF6, and FGF8 were all significantly upregulated at 3 months. BMP8b and BMP9 were significantly upregulated at 3 months. Histologic analysis revealed mucosal, stromal, and mucin gland hypertrophy, increased mucin production, and metaplasia with loss of cilia. Antibody staining was strongly positive in the AF‐treated group.Conclusions:Induction of CRS is associated with time‐dependent changes in tissue remodeling cytokine expression occurring in conjuction with inflammatory tissue changes. Antibody staining for upregulated cytokines suggests local production within the sinonasal mucosa. Further study is required to better understand the association between BMP, FGF, and MMP regulation and tissue remodeling changes resulting from chronic inflammation. Laryngoscope, 2012
Comparison of computed tomography and magnetic resonance imaging for evaluation of cholesteatoma with labyrinthine fistulae
Authors: Sone Michihiko , Yoshida Tadao , Naganawa Shinji , Otake Hironao , Kato Ken , Sano Rui , Teranishi Masaaki , Nakashima Tsutomu 
Published: January 2012

AbstractObjectives/Hypothesis:To compare preoperative computed tomography (CT) and magnetic resonance imaging (MRI) findings to the clinical features in patients with middle ear cholesteatoma with labyrinthine fistulae.Study Design:Retrospective case series.Methods:Twenty‐eight patients who underwent surgery for middle ear cholesteatoma with one or more labyrinthine fistulae confirmed by CT were studied. Preoperative imaging analysis was performed using three‐dimensional fluid‐attenuated inversion recovery (3D‐FLAIR) MRI. Fistula size measured by CT and the signal intensity ratio (SIR) between the affected lesion in the inner ear and the cerebellum measured by 3D‐FLAIR MRI were evaluated with respect to the clinical features and surgical findings.Results:The SIR was not correlated with fistula size. The hearing threshold determined by preoperative bone conduction correlated with the SIR, especially in patients with acute sensorineural hearing loss, but it did not correlate with fistula size. Patients with fistula symptoms had a significantly higher SIR than those without symptoms, and similar findings were observed in patients with an active infection. Patients with a larger fistula or higher SIR tended to have a deeper fistula and a more adhesive fistula matrix at operation.Conclusions:SIR was more strongly correlated than CT findings to the clinical status of patients with labyrinthine fistulae caused by cholesteatoma. Adhesion of the cholesteatoma matrix to the membranous labyrinth correlated with the SIR; thus, SIR may accurately reflect the extent of inner ear dysfunction with a labyrinthine fistula.
Block Copolypeptides Prepared by N‐Carboxyanhydride Ring‐Opening Polymerization
Authors: Habraken Gijs J. M. , Heise Andreas , Thornton Paul. D. 
Published: January 2012

AbstractN‐Carboxyanhydride ring‐opening polymerization (NCA ROP) is a synthetically straightforward methodology to generate homopolypeptides. Extensive control over the polymerization permits the production of highly monodisperse synthetic polypeptides to a targeted molecular weight in the absence of unfavorable side reactions. Sequential NCA ROP permits the creation of block copolypeptides composed of individual polypeptide blocks boasting different functionalities, secondary structures, and desirable chemical properties. Consequently, a plethora of novel materials have been generated that have found wide‐range applicability. This review offers an insight into contemporary synthetic approaches toward NCA ROP before highlighting a number of block copolypeptide architectures generated.
Venous oxygenation mapping using velocity‐selective excitation and arterial nulling
Authors: Guo Jia , Wong Eric C. 
Published: January 2012

AbstractA new MRI technique to map the oxygenation of venous blood is presented. The method uses velocity‐selective excitation and arterial nulling pulses, combined with phase sensitive signal detection to isolate the venous blood signal. T2 of this signal along with a T2–Y calibration curve yields estimates of venous oxygenation in situ. Results from phantoms and healthy human subjects under normoxic and hypoxic conditions are shown, and venous saturation levels estimated from both sagittal sinus and gray matter–based regions of interest are compared with the related techniques TRUST and QUIXOTIC. In addition, combined with an additional scan without arterial nulling pulses, the oxygen saturation level on arterial side can also be estimated. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.
Flip angle profile correction for T1 and T2 quantification with look‐locker inversion recovery 2D steady‐state free precession imaging
Authors: Cooper Mitchell A. , Nguyen Thanh D. , Spincemaille Pascal , Prince Martin R. , Weinsaft Jonathan W. , Wang Yi 
Published: January 2012

AbstractFast methods using balanced steady‐state free precession have been developed to reduce the scan time of T1 and T2 mapping. However, flip angle (FA) profiles created by the short radiofrequency pulses used in steady‐state free precession deviate substantially from the ideal rectangular profile, causing T1 and T2 mapping errors. The purpose of this study was to develop a FA profile correction for T1 and T2 mapping with Look‐Locker 2D inversion recovery steady‐state free precession and to validate this method using 2D spin echo as a reference standard. Phantom studies showed consistent improvement in T1 and T2 accuracy using profile correction at multiple FAs. Over six human calves, profile correction provided muscle T1 estimates with mean error ranging from excellent (−0.6%) at repetition time/FA = 18 ms/60° to acceptable (6.8%) at repetition time/FA = 4.9 ms/30°, while muscle T2 estimates were less accurate with mean errors of 31.2% and 47.9%, respectively. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.
A unified impulse response model for DCE‐MRI
Authors: Schabel Matthias C. 
Published: January 2012

AbstractWe describe the gamma capillary transit time model, a generalized impulse response model for DCE‐MRI that mathematically unifies the Tofts‐Kety, extended Tofts‐Kety, adiabatic tissue homogeneity, and two‐compartment exchange models. By including a parameter (α−1) representing the width of the distribution of capillary transit times within a tissue voxel, the GCTT model discriminates tissues having relatively monodisperse transit time distributions from those having a large degree of heterogeneity. All five models were compared using in vivo data acquired in three brain tumors (one glioblastoma multiforme, one pleomorphic xanthoastrocytoma, and one anaplastic meningioma) and Monte Carlo simulations. Our principal findings are : (1) The four most commonly used models for dynamic contrast‐enhanced magnetic resonance imaging can be unified within a single formalism. (2) Application of the GCTT model to in vivo data incurs only modest penalties in parameter uncertainty and computational cost. (3) Measured nonparametric impulse response functions in human brain tumors are well described by the GCTT model. (4) Estimation of α−1 is feasible but achieving statistical significance requires higher SNR than is typically obtained in single voxel dynamic contrast‐enhanced magnetic resonance imaging data. These results suggest that the GCTT model may be useful for extraction of information about tumor physiology beyond what is obtained using current modeling methodologies. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.
Improved dynamic response assessment for intra‐articular injected iron oxide nanoparticles
Authors: Crowe L. A. , Tobalem F. , Gramoun A. , Delattre B. M. A. , Grosdemange K. , Salaklang J. , Redjem A. , Petri‐Fink A. , Hofmann H. , Vallée J.‐P. 
Published: January 2012

AbstractThe emerging importance of nanoparticle technology, including iron oxide nanoparticles for monitoring development, progression, and treatment of inflammatory diseases such as arthritis, drives development of imaging techniques. Studies require an imaging protocol that is sensitive and quantifiable for the detection of iron oxide over a wide range of concentrations. Conventional signal loss measurements of iron oxide nanoparticle containing tissues saturate at medium concentrations and show a nonlinear/nonproportional intensity to concentration profile due to the competing effects of T1 and T2 relaxation. A concentration calibration phantom and an in vivo study of intra‐articular injection in a rat knee of known concentrations of iron oxide were assessed using the difference‐ultrashort echo time sequence giving a positive, quantifiable, unambiguous iron signal and monotonic, increasing concentration response over a wide concentration range in the phantom with limited susceptibility artifacts and high contrast in vivo to all other tissues. This improved dynamic response to concentration opens possibilities for quantification due to its linear nature at physiologically relevant concentrations. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.
Vibration‐synchronized magnetic resonance imaging for the detection of myocardial elasticity changes
Authors: Elgeti Thomas , Tzschätzsch Heiko , Hirsch Sebastian , Krefting Dagmar , Klatt Dieter , Niendorf Thoralf , Braun Jürgen , Sack Ingolf 
Published: January 2012

AbstractVibration synchronized magnetic resonance imaging of harmonically oscillating tissue interfaces is proposed for cardiac magnetic resonance elastography. The new approach exploits cardiac triggered cine imaging synchronized with extrinsic harmonic stimulation (f = 22.83 Hz) to display oscillatory tissue deformations in magnitude images. Oscillations are analyzed by intensity threshold‐based image processing to track wave amplitude variations over the cardiac cycle. In agreement to literature data, results in 10 volunteers showed that endocardial wave amplitudes during systole (0.13 ± 0.07 mm) were significantly lower than during diastole (0.34 ± 0.14 mm, P < 0.001). Wave amplitudes were found to decrease 117 ± 40 ms before myocardial contraction and to increase 75 ± 31 ms before myocardial relaxation. Vibration synchronized magnetic resonance imaging improves the temporal resolution of magnetic resonance elastography as it overcomes the use of extra motion encoding gradients, is less sensitive to susceptibility artifacts, and does not suffer from dynamic range constraints frequently encountered in phase‐based magnetic resonance elastography. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.
Arch in granular materials as a free surface problem
Authors: Guo Peijun , Zhou Shunhua 
Published: January 2012

SUMMARYThis paper discusses the formation of stable arches in frictional soils. A series of laboratory tests are performed to explore the formation of arches in granular materials, either cohesionless or with small apparent cohesion. By considering the stable soil arch as a stress‐free surface, the analysis in the framework of continuum mechanics reveals that such an arch can only form in cohesive frictional materials. The shape of the arch mainly depends on the material's friction angle, while the critical width of the arch is primarily dominated by cohesion. The formation of stable arches in cohesionless materials is interpreted by taking into account the discrete nature of the material, with the failure of the arch being considered as buckling of particle columns. It is shown that the width of stable arches in cohesionless materials is generally five to seven times of the particle size. Copyright © 2012 John Wiley & Sons, Ltd.
Non‐vacuum deposition of Cu(In,Ga)Se2 absorber layers from binder free, alcohol solutions
Authors: Uhl Alexander R. , Fella Carolin , Chirilă Adrian , Kaelin Marc R. , Karvonen Lassi , Weidenkaff Anke , Borca Camelia N. , Grolimund Daniel , Romanyuk Yaroslav E. , Tiwari Ayodhya N. 
Published: January 2012

ABSTRACTNon‐vacuum methods for Cu(In,Ga)Se2 (CIGS) absorber deposition have gained wide interest because of their inherent cost and energy saving potential. Here, a solution‐based processing route for CIGS absorber layers is presented that employs binder‐free solutions of metal salts in non‐toxic, alcohol solvents. Despite the low‐boiling‐point nature of the employed solvents, a residual carbon‐rich layer is observed between the CIGS and metal back contact. Based on comprehensive investigations by scanning electron microscopy, energy‐/wavelength dispersive X‐ray spectroscopy, X‐ray fluorescence, X‐ray diffraction, thermogravimetric analysis, differential thermal analysis, and extended X‐ray absorption fine structure spectroscopy, a formation reaction mechanism through intermediate metal–organic complexes is proposed. In this route, the CIGS layer is formed in selenium atmosphere via a gradual decomposition of the carbon‐rich layer comprising carboxylic chelate complexes of metals. A compositional gradient occurs in the CIGS absorber, whereas a significant amount of metals remains in the carbon‐rich layer. The incorporation of Ga into CIGS is affected by the initial salt concentration and the selenization temperature. Fabricated solar cells exhibit active area efficiencies of up to 7.7% on 0.3 cm2 area without anti‐reflection coating, which is among the highest reported efficiencies for solar cells from a solution process with non‐explosive gases or solvents. Copyright © 2012 John Wiley & Sons, Ltd.
Autophagy regulates lipolysis and cell survival through lipid droplet degradation in androgen‐sensitive prostate cancer cells
Authors: Kaini Ramesh R. , Sillerud Laurel O. , Zhaorigetu Siqin , Hu Chien‐An A. 
Published: January 2012

AbstractBACKGROUNDAndrogen deprivation therapy, one of the standard treatments for prostate cancer (PCa) induces apoptosis, as well as autophagy in androgen‐responsive PCa cells. As autophagy can promote either cell survival or death, it is important to understand its role in PCa treatment. The objective of this study was to elucidate the function of autophagy in lipid droplet (LD) homeostasis and survival in androgen‐sensitive PCa cells.METHODSTo produce androgen deprivation, charcoal filtered serum or the androgen inhibitor casodex were used in LNCaP and LAPC4 cells. Autophagy was monitored by immunofluorescence/confocal microscopy and immunoblot analysis. Levels of intracellular LDs and triacyglycerols after the inhibition of autophagy by 3‐methyladenine, bafilomycin A1, or si‐ATG5 were quantified by three independent methods, Oil Red O staining, triacyglycerols lipase assay, and nuclear magnetic resonance.RESULTSAndrogen deprivation induced autophagy and the depletion of LDs in both of the androgen‐sensitive PCa cell lines examined, whereas the blockage of autophagy by pharmacological or genetic means inhibited LD degradation and therefore lipolysis and cell growth. In addition, under androgen deprivation, increased colocalization of LDs and autophagic vesicles was observed in LNCaP cells, which can be further enhanced by blocking the autophagic flux.CONCLUSIONAutophagy mediates LD degradation and lipolysis in androgen‐sensitive PCa cells during androgen deprivation which aids the survival of PCa cells during hormone therapy. Prostate 72:1412–1422, 2012. © 2012 Wiley Periodicals, Inc.
Convective boundary‐layer structure in the presence of wind‐following swell
Authors: Nilsson Erik Olof , Rutgersson Anna , Smedman Ann‐Sofi , Sullivan Peter P. 
Published: January 2012

AbstractThe marine boundary layer is known to be influenced by fast long ocean swell waves travelling away from their generation area, where they were initiated by momentum transferred to the ocean wave field during storms. The atmospheric boundary layer during wind‐following swell and various stability states has been investigated using large‐eddy simulation (LES) data. The dominant energy‐containing motions in the near‐neutral atmospheric boundary layer over flat terrain are known to be dominated by near‐ground shear‐induced regions of high‐ and low‐speed flow. Wind fields and momentum fluxes from LES for swell‐dominated situations have been used to interpret field measurements suggesting that these motions are disrupted by effects related to the underlying wave field in the presence of swell waves. Statistical analysis and visualization are used to further describe the effects of stratification during swell for convective boundary‐layer winds and fluxes. A mechanism for transport of momentum to the upper levels of the boundary layer is suggested from interpretation of LES data. Coherent detached eddies from the directly wave‐induced motions near the surface are found to maintain an upward momentum transfer. This mechanism is found to strengthen during stronger swell conditions and also during slightly convective conditions. In this way, it is argued that processes related to both the wave field and surface convection can have a significant influence on the global structure of neutral and convective boundary layers during swell. This has implication for the turbulence length‐scales during wind‐following swell. Copyright © 2012 Royal Meteorological Society