bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of fluorescence in situ hybridization and polymerase chain reaction in the diagnosis and classification of lymphoproliferative disorders on fine‐needle aspiration
Authors: Zhang Songlin , Abreo Fleurette , Lowery‐Nordberg Mary , Veillon Diana M. , Cotelingam James D.
Published: March 2010

BACKGROUND:

Fine‐needle aspiration (FNA) has been used in the evaluation of lymphadenopathy for a long time and is highly reliable in the identification of metastatic malignancies. However, the role of FNA in the assessment of new lymphoproliferative disorders continues to be a subject of debate. The objective of the current study was to evaluate the role of molecular cytogenetic studies in FNA diagnoses of lymphoproliferative disorders.

METHODS:

A retrospective, computer‐based search for lymph node FNAs from 2006 to 2007 was performed. Cases with either fluorescence in situ hybridization (FISH) and/or polymerase chain reaction (PCR) studies were subjected to further analysis.

RESULTS:

In total, 243 lymph node FNAs were performed during the period, including 104 that were positive/suspicious for metastatic malignancies, 16 that were positive/suspicious for lymphomas, 15 that demonstrated atypical lymphoid proliferation, 73 that were reactive, 14 that were deemed granulomas, and 21 that were determined to be nondiagnostic. Molecular analysis included combined FISH/PCR in 4 cases, FISH only in 7 cases, and PCR only in 4 cases. By using multiplex PCR, 6 cases with atypical/negative flow cytometry results were diagnosed as 4 B‐cell lymphomas, 1 T‐cell lymphoma, and 1 reactive lymph node; and 4 cases that had atypical T cells determined by flow cytometry were diagnosed as reactive. One CD10‐negative follicular lymphoma and 2 cases with suspicious flow cytometry results were positive for t(14;18)(q32;q21) by FISH. Forty‐five cases had follow‐up histology with 3 false‐negative findings and no false‐positive results.

CONCLUSIONS:

In this study, multiplex PCR studies for immunoglobulin heavy‐chain or T‐cell receptor gene rearrangements were useful for demonstrating clonality, and FISH studies were able to detect translocations or gene rearrangements that allowed for the subclassification of B‐cell non‐Hodgkin lymphomas. Cancer (Cancer Cytopathol) 2010. © 2010 American Cancer Society.
Synthesis, characterization and gas sensing properties of flowerlike In2O3 composed of microrods
Authors: Lu Xifeng , Yu Qinqin , Wang Kang , Shi Luchuan , Liu Xing , Qiu Aiguo , Wang Lei , Cui Deliang
Published: March 2010

Flowerlike structured In2O3 were successfully synthesized via a hydrothermal process and the subsequent calcinations. The obtained sample consists of microrods with an average diameter of 0.5‐1 μm and a length of 1‐3 μm. Structure and property of the sample were characterized by X‐ray powder diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The sensing properties towards trimethylamine (TMA) were examined at 200‐400 °C, which showed high sensitivity, better selectivity, and prompt response/recovery merits. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Temperature gradient controlled growth and optical properties of Er:BaY2F8 crystals
Authors: Yongfeng Ruan , Shouchao Zhang , Guanghui Li , Wei Zhu , Danli Wang , Lingcui Zhang
Published: March 2010

Single crystals of Erbium (Er) doped BaY2F8 have been obtained by the temperature gradient technique (TGT). No‐seed‐grown crystal of Er:BaY2F8, with the dimensions up to several centimeters, was obtained by self‐crystallization. The optimizations of various growth parameters were systemically investigated. The results indicated that the temperature gradient of 6‐7 K/mm and the cooling velocity less than 6 K/h were suitable for the crystal growth. The XRD data and the investigations on the growth striations by a stereo polarization microscope displayed that the [001] direction is the dominating direction for the crystal growth. The crystal grown by TGT often cracks along with the (100) plane, which is caused by the excessive decrease of the temperature during the crystal growth, for there is a rapid change in the thermal expansion curve of the BaY2F8 crystal in the temperature range from 800 °C to 900 °C. The spectral properties of Er:BaY2F8 single crystals have been studied and the effects of frequency up‐conversion of the crystals are reported. Spectral data suggest that the quality of Er:BaY2F8 crystal obtained by TGT method is good and the crystal has the potential application in laser devices. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Systematic Structural Coordination Chemistry ofp‐tert‐Butyltetrathiacalix[4]arene: Main Group Metal Complexes Other Than Those of Group 1
Authors: Bilyk Alexander , Dunlop John W. , Hall Annegret K. , Harrowfield Jack M. , Hosseini M. Wais , Koutsantonis George A. , Skelton Brian W. , White Allan H.
Published: March 2010

In extension of previous work involving structural characterisation of complex salts formed between main group 1 metal ions andp‐tert‐butyltetrathiacalixarene, LH4, the present study encompasses complexes with a wider array of main group 2, 13, 14 metal ions. For group 2, single‐crystal X‐ray structural characterisation of Ca(LH3)2·3dmf (1a), {Ca(LH2)·3dmf}2(1b), Ba(LH3)2·6dmf (2a) and BaCO3·3Ba(LH3)2·3H2O·3CH3CN·12.25CH2Cl2(2b) provides models for various coordination units. For group 13, this applies to {Ga(OH)(LH2)·3.5dmf}2(3), {In(LH)·4EtOH·2CH2Cl2}2(4a) and {In(OH)(LH2)·3CH2Cl2}4(4b), and for group 14, to OPb4(LH)2·6dmf·dmso·2H2O (5). Overall, these define mononuclear (1a,2a), binuclear (1b,3,4b) and tetranuclear (2b,4b,5) species. The calixarene cavities frequently include solvent molecules, though this capacity is clearly influenced by the nature of the bound metal ion(s) and their binding, as well as the associated impact on the conformation of the calixarene ligand(s).
Luminescent Platinum(II) Complexes Containing Cyclometallated Diaryl Ketimine Ligands: Synthesis, Photophysical and Computational Properties
Authors: Pandya Shashi U. , Moss Kathryn C. , Bryce Martin R. , Batsanov Andrei S. , Fox Mark A. , Jankus Vygintas , Al Attar Hameed A. , Monkman Andrew P.
Published: March 2010

A new series of platinum(II) complexes containing cyclometallated diaryl ketimine ligands has been synthesised. The route involves reaction of diaryl ketimines with K[PtCl3(dmso)] to obtain trans‐[PtCl2(imine)(dmso)] species, which underwent cyclometallation upon heating in toluene to give [PtCl{Ar′(ArC=NH)}(dmso)] complexes 12b–17b. N‐Hydroxy and N‐phenyl analogues 18b and 21 were also synthesised. In complexes 19 and 20 the auxiliary chlorido and dmso ligands were replaced by an acetylacetonato ligand. The photophysical properties of the cyclometallated complexes are reported. The emission bands at λmax ≈ 450 and 550 nm are assigned to mixed‐ligand and MLCT states having significant singlet and triplet character, respectively. By varying the structure of the aromatic ligand the efficiency of phosphorescence can be increased to 4.3 % for 15b (Ar′ = 1‐naphthyl). Theoretical calculations show that the low‐energy transitions in all the cyclometallated systems involve mainly the frontier orbitals, HOMO and LUMO. These are mixed chlorido–metal–ligand to largely π*‐C=N transitions. Most of the observed phosphorescence data can be explained by the geometric change on going from the S0 to the T1 states. An organic light‐emitting device has been fabricated by using complex 15b as the emissive dopant in a poly(vinylcarbazole) host. Broad electroluminescence spanning the range 500–750 nm was observed.
Design of Bisphosphonate‐Terminated Dendrimers
Authors: Cavero Emma , Zablocka Maria , Caminade Anne‐Marie , Majoral Jean Pierre
Published: March 2010

Several new methods for the synthesis of phosphorus dendrimers capped with biologically active azabisphosphonates are reported. Monomers bearing either azido or acetylenic groups were designed as building blocks either for attachment onto the surfaces of classical phosphorus dendrimers or for use in the construction of original dendrimers without the need for use of sensitive dichloro(monomethylhydrazino)thiophosphane.
Pyrazine Biosynthesis in Corynebacterium glutamicum
Authors: Dickschat Jeroen S. , Wickel Susanne , Bolten Christoph J. , Nawrath Thorben , Schulz Stefan , Wittmann Christoph
Published: March 2010

The volatile compounds released by Corynebacterium glutamicum were collected by use of the CLSA technique (closed‐loop stripping apparatus) and analysed by GC‐MS. The headspace extracts contained several acyloins and pyrazines that were identified by their synthesis or comparison to commercial standards. Feeding experiments with [2H7]acetoin resulted in the incorporation of labelling into trimethylpyrazine and tetramethylpyrazine. Several deletion mutants targeting genes of the primary metabolism were constructed to elucidate the biosynthetic pathway to pyrazines in detail. A deletion mutant of the ketol‐acid reductoisomerase was not able to convert the acetoin precursor (S)‐2‐acetolactate into the pathway intermediate (R)‐2,3‐dihydroxy‐3‐methylbutanoate to the branched amino acids. This mutant requires valine, leucine, and isoleucine for growth and produces significantly higher amounts and more different compounds of the acyloin and pyrazine classes. Gene deletion of the acetolactate synthase (AS) resulted in a mutant that is not able to convert pyruvate into (S)‐2‐acetolactate. This mutant also requires branched amino acids and produces only very small amounts of pyrazines likely from valine via the valine biosynthetic pathway operating in reverse order. A ΔASΔKR double mutant was constructed that does not produce any pyrazines at all. These results open up a detailed biosynthetic model for the formation of alkylated pyrazines via acyloins.
Simultaneous Determination of Ascorbic Acid, Dopamine and Uric Acid at Pt Nanoparticles Decorated Multiwall Carbon Nanotubes Modified GCE
Authors: Dursun Zekerya , Gelmez Buket
Published: March 2010

A modified electrode was fabricated by electrochemically deposition of Pt nanoparticles on the multiwall carbon nanotube covered glassy carbon electrode (Pt nanoparticles decorated MWCNT/GCE). A higher catalytic activity was obtained to electrocatalytic oxidation of ascorbic acid, dopamine, and uric acid due to the enhanced peak current and well‐defined peak separations compared with both, bare and MWCNT/GCE. The electrode surfaces were characterized by scanning electron microscopy (SEM), X‐ray diffraction (XRD) and electrochemical impedance spectroscopy (EIS). Individual and simultaneous determination of AA, DA, and UA were studied by differential pulse voltammetry. The detection limits were individually calculated for ascorbic acid, dopamine, and uric acid as being 1.9×10−5 M, 2.78×10−8 M, and 3.2×10−8 M, respectively. In simultaneous determination, LODs were calculated for AA, DA, and UA, as of 2×10−5 M, 4.83×10−8 M, and 3.5×10−7 M, respectively.
A Comparative Study of the Modification of Gold and Glassy Carbon Surfaces with Mixed Layers of In Situ Generated Aryl Diazonium Compounds
Authors: Liu Guozhen , Chockalingham Muthukumar , Khor Sook Mei , Gui Alicia L. , Gooding J. Justin
Published: March 2010

In situ generated aryl diazonium cations were synthesized in the electrochemical cell by reaction of the corresponding amines with NaNO2 in aqueous HCl. This paper reports a study of the formation of mixed layers from in situ generated aryl diazonium cations. Firstly, glassy carbon (GC) and gold electrode surfaces were modified with five single in situ generated aryl diazonium salts to obtain their corresponding reductive potential followed by the modification of GC and gold surfaces with eight binary mixed layers of in situ generated aryl diazonium salts. The difference between GC and gold surfaces in terms of in situ formation of two‐component aryl diazonium salt films was compared. The behavior of the mixed layers formed from in situ generated aryl diazonium salts relative to diazonium salts that were pre‐synthesized prior to surface modification was also investigated. Cyclic voltammetry and X‐ray photoelectron spectroscopy were used to characterize the resulting modified GC and gold surfaces. It is found that for some aryl diazonium salts the potential at which reductive adsorption is achieved on gold and GC surfaces is significantly different. For the eight sets of binary mixed layers, the species with more anodic potential are more difficult to attach to the both GC and gold surfaces. The behavior of the mixed layers formed from in situ generated aryl diazonium salts and the pre‐synthesized diazonium salts is similar; which emphasizes the advantage of the in situ approach without any apparent difference in behavior to the presynthesized diazonium salts.
Evaluating Enzyme Cascades for Methanol/Air Biofuel Cells Based on NAD+‐Dependent Enzymes
Authors: Addo Paul K. , Arechederra Robert L. , Minteer Shelley D.
Published: March 2010

Previous work by the group has entailed encapsulating enzymes in polymeric micelles at bioelectrode surfaces by utilizing hydrophobically modified Nafion membranes, which are modified in order to eliminate the harsh acidity of Nafion while tailoring the size of the polymer micelles to optimize for the encapsulation of an individual enzyme. This polymer encapsulation has been shown to provide high catalytic activity and enzyme stability. In this study, we employed this encapsulation technique in developing a methanol/air biofuel cell through the combined immobilization of NAD+‐dependent alcohol dehydrogenase (ADH), aldehyde dehydrogenase (AldDH) and formate dehydrogenase (FDH) within a tetrabutylammonium bromide (TBAB) modified Nafion to oxidize methanol to carbon dioxide with poly(methylene green) acting as the NADH electrocatalyst electropolymerized on the surface of the electrode. The methanol biofuel/air cell resulted in a maximum power density of 261±7.6 μW/cm2 and current density of 845±35.5 μA/cm2. This system was characterized for the effects of degree of oxidation, temperature, pH, and concentration of fuel and NAD.
Separation and quantification of double‐ and triple‐layered rotavirus‐like particles by CZE
Authors: Castro‐Acosta Ricardo M. , Revilla Alma L. , Ramírez Octavio T. , Palomares Laura A.
Published: March 2010

Virus‐like particles have been successfully used as safe vaccines, as their structure is identical to their native counterparts but devoid of the viral genetic material. However, production of these complex structures is not easy, as recombinant proteins must assemble into virus‐like particles. Techniques to differentiate assembled and soluble proteins, as well as assembly intermediaries often present in a sample, are required. An example of complex virus‐like particles mixture occurs when rotavirus proteins are recombinantly expressed. Rotavirus‐like particles (RLP) can be single (sl), double (dl), or triple layered (tl). The use of RLP preparations as vaccines requires their complete characterization, including separation and quantification of each RLP in a sample. In this work, CZE was evaluated for the separation and quantification of dl and triple‐layered rotavirus‐like particles (tlRLP). A fused‐silica capillary with a deoxycholate running buffer efficiently separated dl and tlRLP in RLP preparations, as they migrated in two discrete peaks with electrophoretic mobilities of 1.24±0.04 and 2.95±0.03 Ti, respectively. Standard curves for dl and tlRLP were generated, and the response was linearly proportional to analyte concentration. The methodology developed was quantitative, specific, accurate, precise, and reproducible. CZE allowed the quantitative characterization of RLP preparations, which is required for evaluation of immunogens, for process development, and for quality control protocols.
Chemical and energetic characterization of species with a high‐biomass production: Fractionation of their components
Authors: Franscisco López , Juan Carlos García , Antonio Pérez , M. Javier Feria , Minerva A.M. Zamudio , Gil Garrote
Published: March 2010

In this work, we determined the properties of cellulose pulp and paper from six different lignocellulosic materials [Eucalyptus globulus, Arundo donax, Leucaena diversifolia, Paulownia fortunei, sunflower stalks, and Chamaecytisus proliferus (tagasaste)], as well as the heating value and chemical composition of their autohydrolysis liquor, with a view to assessing their potential for the obtainment of energy, sugars, and other chemical products. An integral fractionation method based on autohydrolysis and organosolv delignification was used for this purpose. L. diversifolia, P. fortunei, a Paulownia “trihybrid” consisting of elongata, tormentosa, and fortunei varieties; sunflower stalks; and C. proliferus exhibited holocellulose, glucan, xylan, and acetyl group contents similar to, or higher than, those of E. globulus, A. donax, and various other lignocellulosic materials. The amounts of oligomers extracted from C. proliferus, P. fortunei, L. diversifolia, and sunflower stalks at the highest temperatures studied exceeded those provided by eucalyptus. Sequential autohydroysis and organosolv delignification of L. diversifolia and C. proliferus provided cellulose pulp with an acceptable kappa number and paper sheets with good strength‐related properties. P. fortunei was the most interesting raw material among those tested; in fact, it provided ethanol pulp with a lignin content of 3.7− 15.3% and a kappa number of 40.5–74.1 after autohydrolysis at 190°C, and paper with a tensile index of 17.0–28.9 kN m/kg. These properties are similar to those of pulp and paper from eucalyptus wood. In addition, P. fortunei exhibited the highest heating value among the studied materials (4683.8 cal/g). © 2010 American Institute of Chemical Engineers Environ Prog, 2010
A dynamic temperature model of mine water‐fed raceways used for microalgae biofuel production
Authors: Shang H. , Scott J.A. , Ross G.M. , Shepherd S.
Published: March 2010

The mining industry is an extremely high consumer of energy, much of which is sourced from fossil fuels. The industry also generates outflows of “waste” energy in discharged gas, air, and water streams. Both the dependence on, and the environmental impacts of, fossil fuels could be reduced by on‐site energy recovery schemes that make use of both waste energy and the large tracts of the otherwise marginal or nonproductive land that mines sites create and occupy. One such possibility lies in the potential for on‐site use of the warm mine water from dewatering in raceways to support microalgae growth for biodiesel production. Mines are, however, often located in remote regions that can experience a significant range in seasonal ambient temperatures. In this article, a model that can be used to estimate the dynamic impact of a wide range of annual climatic conditions on the temperature of a specific volume of mine water flowing along a microalgae raceway is reported. © 2010 American Institute of Chemical Engineers Environ Prog, 2010
Experimental field assessment of suspended sediment pathways for characterizing hydraulic habitat
Authors: Harvey Gemma L. , Clifford Nicholas J.
Published: March 2010

The distribution of particulate matter within river channels, including sediments, nutrients and pollutants, is fundamental to the survival of aquatic organisms. However, the interactions between flow and sediment transport at the patch scale of river systems represents an under‐researched component of physical habitat studies, particularly those concerning the characterization of ‘physical biotopes’ (riffles, runs, pools, glides). This paper describes a field methodology for exploring the transfer of particulate matter at small scales within river channels, which may be used to aid hydraulic habitat characterization. The field protocol combines field measurement of high frequency flow properties, to characterize hydraulic habitat units, and deployment of spatial arrays of turbidity probes, to detect the passage of artificially‐induced sediment plumes through different biotope units. Sediment plumes recorded by the probes are analysed quantitatively in the manner of the flood hydrograph, and qualitative inferences are made on the dominant mixing processes operating within different parts of the channel. Relationships between the nature of spatio‐temporal hydraulic variations within glide, riffle and pool biotopes, and the character and mixing behaviour of sediment plumes within these habitat units are identified. Results from these preliminary experiments suggest that investigating and characterizing the transfer and storage of sediments, nutrients and pollutants within and between different biotopes is a viable avenue for further research, with potential to contribute to improved physical habitat characterization for river management and habitat restoration. The experiments are also an illustration of the value of neglected synergies between process geomorphology, ecology and river hydraulics. Copyright © 2010 John Wiley & Sons, Ltd.
New proposals for the quantification of qualitative survey data
Authors: Proietti Tommaso , Frale Cecilia
Published: March 2010

In this paper we propose and evaluate two new methods for the quantification of business surveys concerning the qualitative assessment of the state of the economy. The first is a nonparametric method based on the spectral envelope, originally proposed by Stoffer, Tyler and McDougall (Spectral analysis for categorical time series: scaling and the spectral envelope, Biometrika 80: 611–622) to the multivariate time series of the counts in each response category. Secondly, we fit by maximum likelihood a cumulative logit unobserved components models featuring a common cycle. The conditional mean of the cycle, which can be evaluated by importance sampling, offers the required quantification. We assess the validity of the two methods by comparing the results with a standard quantification based on the balance of opinions and with a quantitative economic indicator. Copyright ? 2010 John Wiley & Sons, Ltd.
Anterior cingulate activity and the self in disorders of consciousness
Authors: Qin Pengmin , Di Haibo , Liu Yijun , Yu Senming , Gong Qiyong , Duncan Niall , Weng Xuchu , Laureys Steven , Northoff Georg
Published: March 2010

Objectives: The aim of this study was to investigate the relationship between medial cortical activation and the presence of self and consciousness in healthy subjects and patients with vegetative state and minimally conscious state using functional magnetic resonance imaging (fMRI). Experiment design: We first conducted two fMRI experiments in healthy subjects to identify brain regions specifically associated with self‐perception through the use of different auditory stimuli that had different grades of self‐relatedness. We then applied these regions as functional localizers to examine the relationship between neural activity changes during self‐relatedness and consciousness level in the patients with disorders of consciousness (DOC). Principal observations: We demonstrated recruitment of various anterior medial cortical regions including the anterior cingulate cortex (ACC) in healthy subjects during auditory perception of self‐related stimuli. We further showed that patients with DOC showed signal changes in the ACC during auditory perception of self‐related stimuli. Finally, it was shown that these signal changes correlate with the level of consciousness in the patients with DOC. Conclusion: The degree of consciousness in patients with DOC was correlated with neural activity in the ACC induced by self‐related stimuli. Our results not only shed light on the pathophysiology of DOC, but may also suggest a useful neural, and thus diagnostic, marker of the dysfunction of consciousness in vegetative patients. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.
Dehydration affects brain structure and function in healthy adolescents
Authors: Kempton Matthew J. , Ettinger Ulrich , Foster Russell , Williams Steven C.R. , Calvert Gemma A. , Hampshire Adam , Zelaya Fernando O. , O'Gorman Ruth L. , McMorris Terry , Owen Adrian M. , Smith Marcus S.
Published: March 2010

It was recently observed that dehydration causes shrinkage of brain tissue and an associated increase in ventricular volume. Negative effects of dehydration on cognitive performance have been shown in some but not all studies, and it has also been reported that an increased perceived effort may be required following dehydration. However, the effects of dehydration on brain function are unknown. We investigated this question using functional magnetic resonance imaging (fMRI) in 10 healthy adolescents (mean age = 16.8, five females). Each subject completed a thermal exercise protocol and nonthermal exercise control condition in a cross‐over repeated measures design. Subjects lost more weight via perspiration in the thermal exercise versus the control condition (P < 0.0001), and lateral ventricle enlargement correlated with the reduction in body mass (r = 0.77, P = 0.01). Dehydration following the thermal exercise protocol led to a significantly stronger increase in fronto‐parietal blood‐oxygen‐level‐dependent (BOLD) response during an executive function task (Tower of London) than the control condition, whereas cerebral perfusion during rest was not affected. The increase in BOLD response after dehydration was not paralleled by a change in cognitive performance, suggesting an inefficient use of brain metabolic activity following dehydration. This pattern indicates that participants exerted a higher level of neuronal activity in order to achieve the same performance level. Given the limited availability of brain metabolic resources, these findings suggest that prolonged states of reduced water intake may adversely impact executive functions such as planning and visuo‐spatial processing. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.
A phase synchrony measure for quantifying dynamic functional integration in the brain
Authors: Aviyente Selin , Bernat Edward M. , Evans Westley S. , Sponheim Scott R.
Published: March 2010

The temporal coordination of neural activity within structural networks of the brain has been posited as a basis for cognition. Changes in the frequency and similarity of oscillating electrical potentials emitted by neuronal populations may reflect the means by which networks of the brain carry out functions critical for adaptive behavior. A computation of the phase relationship between signals recorded from separable brain regions is a method for characterizing the temporal interactions of neuronal populations. Recently, different phase estimation methods for quantifying the time‐varying and frequency‐dependent nature of neural synchronization have been proposed. The most common method for measuring the synchronization of signals through phase computations uses complex wavelet transforms of neural signals to estimate their instantaneous phase difference and locking. In this article, we extend this idea by introducing a new time‐varying phase synchrony measure based on Cohen's class of time–frequency distributions. This index offers improvements over existing synchrony measures by characterizing the similarity of signals from separable brain regions with uniformly high resolution across time and frequency. The proposed measure is applied to both synthesized signals and electroencephalography data to test its effectiveness in estimating phase changes and quantifying neural synchrony in the brain. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.
Frontal and parietal contributions to arithmetic fact retrieval: A parametric analysis of the problem‐size effect
Authors: Jost Kerstin , Khader Patrick H. , Burke Michael , Bien Siegfried , Rösler Frank
Published: March 2010

The goal of the present study was to investigate the neuroanatomical basis of arithmetic fact retrieval. The rationale was that areas playing a crucial role in arithmetic fact retrieval should show a systematic increase of activation with increasing retrieval effort. To achieve this goal, we utilized the problem‐size effect as this is known to be systematically related to retrieval effort. In contrast to many previous studies, we here took a parametric approach to account for the continuous increase of retrieval effort with problem size. BOLD signals were modeled with problem size as parametric regressor and negative slow waves of the EEG were categorized into six levels of problem size. The fMRI data showed that activation in the angular gyrus and ACC/SMA increased parametrically with problem size. The ERP data showed a systematic amplitude increase with increasing problem size, especially at fronto‐central electrodes. Consistent with the fMRI data, source modeling localized this effect to the ACC. While these findings support previous notions about the crucial role of the angular gyrus during fact retrieval, they also provide evidence that the medial frontal cortex is involved when single‐digit multiplications are solved. Thus, both parietal and frontal structures seem to be integral parts of a system that enables and controls arithmetic fact retrieval. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.
Genetic variation in G72 correlates with brain activation in the right middle temporal gyrus in a verbal fluency task in healthy individuals
Authors: Krug Axel , Markov Valentin , Krach Sören , Jansen Andreas , Zerres Klaus , Eggermann Thomas , Stöcker Tony , Shah N Jon , Nöthen Markus M , Georgi Alexander , Strohmaier Jana , Rietschel Marcella , Kircher Tilo
Published: March 2010

The D‐amino acid oxidase activator gene (G72) has been found associated with several psychiatric disorders such as schizophrenia, major depression, and bipolar disorder. Impaired performance in verbal fluency tasks is an often replicated finding in the mentioned disorders. In functional neuroimaging studies, this dysfunction has been linked to signal changes in prefrontal and lateral temporal areas and could possibly constitute an endophenotype. Therefore, it is of interest whether genes associated with the disorders, such as G72, modulate verbal fluency performance and its neural correlates. Ninety‐six healthy individuals performed a semantic verbal fluency task while brain activation was measured with functional MRI. All subjects were genotyped for two single nucleotide polymorphisms (SNP) in the G72 gene, M23 (rs3918342) and M24 (rs1421292), that have previously shown association with the above‐mentioned disorders. The effect of genotype on brain activation was assessed with fMRI during a semantic verbal fluency task. Although there were no differences in performance, brain activation in the right middle temporal gyrus (BA 39) and the right precuneus (BA 7) was positively correlated with the number of M24 risk alleles in the G72 gene. G72 genotype does modulate brain activation during language production on a semantic level in key language areas. These findings are in line with structural and functional imaging studies in schizophrenia, which showed alterations in the right middle temporal gyrus. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.
A new tablet for writing and drawing during functional MRI
Authors: Tam Fred , Churchill Nathan W. , Strother Stephen C. , Graham Simon J.
Published: March 2010

Writing and drawing are understudied with fMRI, partly for lack of a device that approximates these behaviors well while supporting task feedback and quantitative behavioral logging in the confines of the magnet. Consequently, we developed a tablet based on touchscreen technology that is accurate, reliable, relatively inexpensive, and fMRI compatible. After confirming fMRI compatibility, we conducted preliminary fMRI experiments examining the neural correlates of a widely used pen‐and‐paper neuropsychological assessment, the trail making test. In two subjects, we found left hemisphere frontal lobe activations similar to the major results of a previous group study, and we also noted individual differences mostly in the right hemisphere. These results demonstrate the utility of the new tablet for adaptations of pen‐and‐paper tests and suggest possible uses of the tablet for longitudinal, within‐subjects studies of disease or therapy. We also discuss using the tablet for several other types of tests requiring many, continuous, or two‐dimensional responses that were previously very difficult to perform during fMRI. Hum Brain Mapp, 2011. © 2010 Wiley‐Liss, Inc.
Stream exports of coarse matter and phosphorus following wildfire in NE Victoria, Australia
Authors: Noske Philip J. , Lane Patrick N. J. , Sheridan Gary J.
Published: March 2010

The temporal change in total phosphorus (TP) export from two burnt upland catchments is reported. Following wildfire in January 2003, two burnt forested headwater catchments (136 and 244 ha) in the East Kiewa valley, Victoria, were instrumented to measure discharge, turbidity and to collect stream water samples. In addition, samplers were positioned in the stream bed at the outlet of each catchment to continuously sample material transported along the bed of the stream. Approximately, every 2 weeks, the material collected by the stream bed samplers was weighed and sub‐sampled. The percentage of coarse (>1 and < 5 mm in diameter) mineral (including soil aggregates) and organic matter was determined and then analysed for TP. Between the first and third years after fire, sampled coarse matter and associated TP loads decreased by an average of 53% and 62%, respectively. Over the 3‐year study, the amount of coarse matter exported during winter/spring decreased considerably, whereas export rates during summer/autumn remained relatively constant. Coarse matter exports were estimated to be approaching pre‐fire levels after 3–4 years. Results on total suspended solids (TSS) TP and total dissolved phosphorus (TDP) from a parallel study are incorporated to explore TP partitioning. TP exported with TSS dominated the total TP export loads, with coarse matter TP and TDP each contributing approximately 10% over the study period. Copyright © 2010 John Wiley & Sons, Ltd.
Isotopes and geochemistry in a managed aquifer recharge scheme: a case study of fresh water injection at the Damascus University Campus, Syria
Authors: Kattan Z. , Kadkoy N. , Nasser S. , Safadi M. , Hamed A.
Published: March 2010

A combination of stable isotopes (18O and 2H) and hydrochemistry has been applied to investigate storage processes in relation to aquifer storage and recovery (ASR) of the shallow alluvial Quaternary aquifer in Damascus basin. The stored water, entirely taken from the Figeh springs during flood periods, was injected in a single well having a brackish groundwater. Water samples were collected from four observation wells drilled in the Damascus University Campus (DUC) site during a 3‐year period (2006–2008). The injectant water, which deviates in its chemical and isotopic signatures from that of the ambient groundwater, shows that the stored water plume remains within close proximity to the injection well (IW) (<≈ 100 m). Thus, only two wells (W13 and W14) located at a distance less than 80 m from the injection point were affected by this injection. The observation wells located at longer distances from the IW (≈145 m and ≈ 600 m for wells W15 and WHz, respectively) were completely unaffected by the injection. Although most of the chemical and isotopic parameters usefully reflected the mixing process that occurs between the injectant water and ambient groundwater, the stable isotope (18O) and chloride (Cl−) were the most sensitive parameters that quickly reflect this signature. Using a simple mass balance, the calculated proportion of injectant water reaching the well W13 was in the range of 50–90%. This proportion was even lower (30–55%) in the case of well W14. Although the drought event prevailing during this study did not much help to inject further amounts of water, higher than the injected volume (0·2416 M m3) and also not favourable to better evaluate the fate and subsurface hydrological processes, these findings offer encouragement to continue the ASR activities, as an alternative way for better management of water resources in this basin facing intensive problems. Copyright © 2010 John Wiley & Sons, Ltd.
Snow accumulation distribution inferred from time‐lapse photography and simple modelling
Authors: Farinotti Daniel , Magnusson Jan , Huss Matthias , Bauder Andreas
Published: March 2010

The spatial and temporal distribution of snow accumulation is complex and significantly influences the hydrological characteristics of mountain catchments. Many snow redistribution processes, such as avalanching, slushflow or wind drift, are controlled by topography, but their modelling remains challenging. In situ measurements of snow accumulation are laborious and generally have a coarse spatial or temporal resolution. In this respect, time‐lapse photography shows itself as a powerful tool for collecting information at relatively low cost and without the need for direct field access. In this paper, the snow accumulation distribution of an Alpine catchment is inferred by adjusting a simple snow accumulation model combined with a temperature index melt model to match the modelled melt‐out pattern evolution to the pattern monitored during an ablation season through terrestrial oblique photography. The comparison of the resulting end‐of‐winter snow water equivalent distribution with direct measurements shows that the achieved accuracy is comparable with that obtained with an inverse distance interpolation of the point measurements. On average over the ablation season, the observed melt‐out pattern can be reproduced correctly in 93% of the area visible from the fixed camera. The relations between inferred snow accumulation distribution and topographic variables indicate large scatter. However, a significant correlation with local slope is found and terrain curvature is detected as a factor limiting the maximal snow accumulation. Copyright © 2010 John Wiley & Sons, Ltd.
Regional flood frequency analysis using residual kriging in physiographical space
Authors: Nezhad M. Kamali , Chokmani K. , Ouarda T. B. M. J. , Barbet M. , Bruneau P.
Published: March 2010

In this article, an approach using residual kriging (RK) in physiographical space is proposed for regional flood frequency analysis. The physiographical space is constructed using physiographical/climatic characteristics of gauging basins by means of canonical correlation analysis (CCA). This approach is a modified version of the original method, based on ordinary kriging (OK). It is intended to handle effectively any possible spatial trends within the hydrological variables over the physiographical space. In this approach, the trend is first quantified and removed from the hydrological variable by a quadratic spatial regression. OK is therefore applied to the regression residual values. The final estimated value of a specific quantile at an ungauged station is the sum of the spatial regression estimate and the kriged residual. To evaluate the performance of the proposed method, a cross‐validation procedure is applied. Results of the proposed method indicate that RK in CCA physiographical space leads to more efficient estimates of regional flood quantiles when compared to the original approach and to a straightforward regression‐based estimator. Copyright © 2010 John Wiley & Sons, Ltd.
Above‐stream microclimate and stream surface energy exchanges in a wildfire‐disturbed riparian zone
Authors: Leach J. A. , Moore R. D.
Published: March 2010

Stream temperature and riparian microclimate were characterized for a 1·5 km wildfire‐disturbed reach of Fishtrap Creek, located north of Kamloops, British Columbia. A deterministic net radiation model was developed using hemispherical canopy images coupled with on‐site microclimate measurements. Modelled net radiation agreed reasonably with measured net radiation. Air temperature and humidity measured at two locations above the stream, separated by 900 m, were generally similar, whereas wind speed was poorly correlated between the two sites. Modelled net radiation varied considerably along the reach, and measurements at a single location did not provide a reliable estimate of the modelled reach average. During summer, net radiation dominated the surface heat exchanges, particularly because the sensible and latent heat fluxes were normally of opposite sign and thus tended to cancel each other. All surface heat fluxes shifted to negative values in autumn and were of similar magnitude through winter. In March, net radiation became positive, but heat gains were cancelled by sensible and latent heat fluxes, which remained negative. A modelling exercise using three canopy cover scenarios (current, simulated pre‐wildfire and simulated complete vegetation removal) showed that net radiation under the standing dead trees was double that modelled for the pre‐fire canopy cover. However, post‐disturbance standing dead trees reduce daytime net radiation reaching the stream surface by one‐third compared with complete vegetation removal. The results of this study have highlighted the need to account for reach‐scale spatial variability of energy exchange processes, especially net radiation, when modelling stream energy budgets. Copyright © 2010 John Wiley & Sons, Ltd.
Antecedent soil moisture conditions of different soil types in South‐western Ontario, Canada
Authors: Nishat S. , Guo Y. , Baetz B. W.
Published: March 2010

Soil moisture conditions prior to input design storms need to be known in the planning and design of urban stormwater control facilities using the design storm approach. Limited information is available on these soil moisture conditions which are commonly referred to as the antecedent soil moisture conditions. In this study, a deterministic continuous simulation model was used to simulate antecedent soil moisture conditions under south‐western Ontario, Canada, climate conditions. A wide range of different soil types were investigated and various statistical analyses on the simulated antecedent soil moisture results were performed. Frequency analyses illustrated typical distributions of antecedent soil moisture conditions and the influence of finer and coarser textured soil particles. Empirical equations were developed for the estimation of average antecedent soil moisture conditions based on commonly known soil characteristics. Satisfactory performance of the empirical equations was demonstrated by comparing between field average antecedent soil moisture data and empirically estimated average antecedent soil moisture values. These equations are therefore recommended for use in urban stormwater studies incorporating the design storm approach. Copyright © 2010 John Wiley & Sons, Ltd.
Cancer‐associated fibroblasts and epithelial‐mesenchymal transition in metastatic oral tongue squamous cell carcinoma
Authors: Vered Marilena , Dayan Dan , Yahalom Ran , Dobriyan Alex , Barshack Iris , Bello Ibrahim O. , Kantola Saara , Salo Tuula
Published: March 2010

We examined cancer‐associated fibroblasts (CAFs) and a panel of immunohistochemical markers of epithelial‐mesenchymal transition (EMT) in 19 pair‐matched oral tongue squamous cell carcinoma (SCC) and metastatic tumors to regional lymph nodes (RLNs). α‐Smooth muscle actin (α‐SMA) was studied to identify CAFs. EMT was studied with syndecan‐1, Cadherin‐11, fibroblast‐specific protein (FSP)‐1, secreted protein acidic and rich in cysteine (SPARC) and Twist. Triple immunostaining in RLNs was used to highlight the carcinoma cells (E‐cadherin and Ki‐67) and their relationship to the CAFs (α‐SMA). We found that metastatic RLNs hosted CAFs similarly as in pair‐matched primary tumors. Expression of EMT markers is common in both primary and metastatic tumors. We demonstrate that metastatic carcinoma cells (Ki‐67 positive) downregulate E‐cadherin expression at the periphery of cancer islands, where they are in direct contact with CAFs. The supporting connective tissue microenvironment also commonly expresses syndecan‐1, Cadherin‐11, FSP‐1, and SPARC. In conclusion, CAFs are common to both primary and metastatic SCC. We hypothesize that CAFs not only promote tumor invasion but also facilitate metastases, either by cometastasizing and/or being recruited to lymph nodes. Evidence of EMT is common within primary tumors and metastatic SCC and may be further modulated by CAFs.
The assessment context: Accreditation, accountability, and performance
Authors: Volkwein J. Fredericks
Published: March 2010

This chapter discusses the drivers for assessment and enables readers to understand the tensions arising within colleges and universities in regard to accountability, accreditation, and performance evaluation.
A model for assessing institutional effectiveness
Authors: Volkwein J. Fredericks
Published: March 2010

This chapter proposes a model for assessing institutional effectiveness and provides a foundation for the other chapters in this volume.
Assessing general education outcomes
Authors: Yin Alexander C. , Volkwein J. Fredericks
Published: March 2010

This chapter identifies key elements of general education assessment, including the advantages and disadvantages of different approaches and the available instruments.
Assessing student learning in the major field of study
Authors: Volkwein J. Fredericks
Published: March 2010

This chapter summarizes the diverse assessment methods and strategies for measuring student academic attainment and describes the key elements in one university's assessment implementation.
Assessing alumni outcomes
Authors: Volkwein J. Fredericks
Published: March 2010

Evaluative statements from alumni have legitimacy with both internal and external stakeholders. Thus, alumni studies can provide valuable evidence of institutional effectiveness and lend themselves to both locally designed and commercial survey instruments for data collection.
Scanning fiber endoscopy with highly flexible, 1 mm catheterscopes for wide‐field, full‐color imaging
Authors: Lee Cameron M. , Engelbrecht Christoph J. , Soper Timothy D. , Helmchen Fritjof , Seibel Eric J.
Published: March 2010

In modern endoscopy, wide field of view and full color are considered necessary for navigating inside the body, inspecting tissue for disease and guiding interventions such as biopsy or surgery. Current flexible endoscope technologies suffer from reduced resolution when device diameter shrinks. Endoscopic procedures today, using coherent fiber‐bundle technology on the scale of 1 mm, are performed with such poor image quality that the clinician's vision meets the criteria for legal blindness. Here, we review a new and versatile scanning fiber‐imaging technology and describe its implementation for ultrathin and flexible endoscopy. This scanning fiber endoscope (SFE) or catheterscope enables high‐quality, laser‐based, video imaging for ultrathin clinical applications, while also providing new options forin vivobiological research of subsurface tissue and high resolution fluorescence imaging. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)