bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of the Chemical Reactions from Two Electrogenerated Species in Picoliter Volumes by Scanning Electrochemical Microscopy
Authors: Wang Qian , Rodríguez‐López Joaquín , Bard Allen J.
Published: August 2010

The volume created by the positioning of two scanning electrochemical microscope (SECM) probes (tip and substrate) at a micrometric distance defines a “picoliter beaker” where homogeneous electron‐transfer reactions are studied. The SECM is used to concurrently electrogenerate in situ two reactive species and to evaluate the possibility of detecting their reactivity. Two reaction cases are studied: the first, called the “reversible case”, occurs when the electrochemically generated species at the substrate electrode can also react at the tip to yield the same product as the reaction in the gap. The second case, named the “irreversible case”, occurs when the electrochemically generated species at the substrate are not able to react at the tip. Digital simulations are performed and compared to experimental studies. These show that an unusual compensation between collection and feedback effects render the analysis inapplicable in the “reversible case”. The “irreversible case” is shown experimentally.
Cued platform training reveals early development of directional responding among preweanling rats in the Morris water task
Authors: Akers Katherine G. , Candelaria‐Cook Felicha T. , Rice James P. , Johnson Travis E. , Hamilton Derek A.
Published: August 2010

Previous studies on the ontogeny of spatial learning report that rats younger than 19–21 days of age are incapable of learning the location of a platform relative to distal cues in the Morris water task. Here, we manipulated the spatial relationship of a cued platform to the pool and the distal visual room cues to investigate whether distal cues can control navigation among 16‐ to 24‐day‐old rats. Rats were trained to navigate to a cued platform in a rich distal cue environment. During critical test trials, the pool was shifted to a different, overlapping position and the cued platform was placed either in the same absolute location in the room or the same relative location in the pool as during training. Rats aged 17 days and older exhibited a disruption in performance when the cued platform was in the absolute location but not the relative location, indicating that rats had learned the direction of the cued platform within the distal cue environment. These observations indicate that (1) information acquired from distal room cues influences navigation as early as 17 days of age, (2) this distal cue information is preferentially used to guide navigation in a particular direction rather than to a precise place in the room, and (3) the directional nature of the influence of distal cues on navigation is invariant across development. © 2010 Wiley Periodicals, Inc. Dev Psychobiol 53: 1–12, 2011.
The response of sap flow in desert shrubs to environmental variables in an arid region of China
Authors: Liu Bing , Zhao Wenzhi , Jin Bowen
Published: August 2010

A case study was conducted in a desert–oasis ecotone in the middle of China's Heihe River basin to reveal the response of sap velocity to environmental variables. We measured sap flow in the branches and stems of desert shrubs (Nitraria sphaerocarpa and Elaeagnus angustifolia) using sap‐flow gauges, and simultaneously measured environmental variables at the study site. The relationships between sap velocity and the environmental variables were analysed using redundancy analysis. The diurnal variation in sap velocity was best described by a bimodal curve, except for the branches of N. sphaerocarpa, which followed a unimodal curve. Sap flow began about 1 h earlier in the branches than in the stems. The dynamic variations in sap velocity were remarkably similar for the two species at a given position (stem vs branch) but differed between the two positions for each species. Redundancy analysis and Kendall's tau analysis indicated that precipitation had the greatest influence on sap velocity in the stem, whereas precipitation duration significantly affected sap velocity in the branches of the desert shrubs (R2 = 0·85 and 0·73, respectively). The variation in sap velocity could be described by a multiple linear regression against the meteorological variables, and the simulated value was significantly linearly correlated with the measured value (0·861 ≤ R2 ≤ 0·938, P < 0·0001). Copyright © 2010 John Wiley & Sons, Ltd.
N,N,O Ligands Based on Triazoles and Transition Metal Complexes Thereof
Authors: Hübner Eike , Fischer Nina V. , Heinemann Frank W. , Mitra Utpal , Dremov Viacheslav , Müller Paul , Burzlaff Nicolai
Published: August 2010

The reaction of 2H‐benzotriazole (1) with dichloroacetic acid leads to the symmetric bis(2H‐benzotriazol‐2‐yl)methane (2c) in 40 % yield. Deprotonation of 2c at the bridging methylene group and subsequent carboxylation with CO2 yielded the new tripodal N,N,O ligand bis(2H‐benzotriazol‐2‐yl)acetic acid Hbbta (3). The sterically less demanding sodium 3,3‐bis(1H‐1,2,4‐triazol‐1‐yl)propionate Na[btp] (5) was obtained by saponification of methyl 3,3‐bis(1H‐1,2,4‐triazol‐1‐yl)propionate (4). The heteroscorpionate ligand 3 was treated with [MnBr(CO)5] and [RuCl2(PPh3)3] to form the manganese tricarbonyl complex [Mn(bbta)(CO)3] (6) and the air stable ruthenium complex [Ru(bbta)Cl(PPh3)2] (7). DFT calculations and the IR spectra of the carbonyl complex 6 reveal ligand 3 to be a less electron‐donating ligand compared to the bis(1H‐pyrazol‐1‐yl)acetic acid Hbpza. In case of the 1H‐1,2,4‐triazole‐based ligand 5 formation of coordination polymers were observed as proven by the synthesis of [Zn(btp)2]∞ (8) and [Mn(btp)2]∞ (9). Polymer 8 crystallises in linear chains of zinc atoms bridged by two molecules of ligand 5 each. These polymer chains show an interesting π‐stacking interaction between uncoordinated triazole residues of the ligands. Deposition of the coordination polymer on highly ordered pyrolytic graphite (HOPG) was successful and was analysed by scanning tunnelling microscopy (STM). Reaction of Na[btp] (5) with MnSO4·H2O resulted in a metal organic framework (MOF) [Mn(btp)2]∞ (9).
Social dominance‐based threat reactions to immigrants in need of assistance
Authors: Costello Kimberly , Hodson Gordon
Published: August 2010

The present investigation examined how individuals higher in social dominance orientation (SDO) react to experimentally induced intergroup threat in terms of support for helping immigrants. Participants read editorials describing an incoming immigrant outgroup posing realistic threats (to tangible resources and well‐being), symbolic threats (to values and traditions) or no threats. Participants higher in SDO exhibited greater resistance to helping immigrants upon exposure to realistic, symbolic, (Experiments 1 and 2), or combined realistic–symbolic (Experiment 2) intergroup threats, but not when the same immigrants posed no threats. In Experiment 2, SDO exerted indirect effects on modern prejudice through both heightened infra‐humanization and intergroup anxiety, with modern prejudice itself predicting greater resistance and indifference to helping immigrants. Moderated mediation analyses revealed strongest SDO‐infra‐humanization relations under conditions of symbolic threat. Implications for prejudice‐reduction interventions are considered. Copyright © 2010 John Wiley & Sons, Ltd.
Das Vorkommen von Fraxinus coriariaefolia Scheele in der Flora Rumäniens und ihre Unterschiede gegenüber F. pallisae Wilm. und F. holotricha Koehne
Authors: Georgescu Const. C. , Tutunaru V.
Published: August 2010

Aus der Norddobrudscha wird das Vorkommen eines kaukasischen Elementes F. coriariaefolia Scheele gemeldet. Die Ökologie dieser Art ist von derjenigen von F. pallisae Wilm. verschieden, mit der sie früher verwechselt wurde.

Die erstere Art ist ein ostpontisches, submontanes, halbxerophiles Element aus verhältnismäßig trockenen Standorten; die zweite Art ist westpontisch in den rumänischen und bulgarischen Ebenen endemisch, halbhydrophil bis mesophil in Standorten mit hohem Grundwasserspiegel.
Eine neue Art in der Gattung Matthiola aus Iran
Authors: Ponert Jiří
Published: August 2010

Vom Gebiet der iranischen Elbors‐Gebirge wird eine neue Art der Gattung Matthiola (Matthiola subglabra Ponert) beschrieben und abgebildet. Verf. beobachtete die neue Art am östlichen Abhang in 2700 m Höhe s. m. Diese Art ist fast kahl und durch lange Früchte sowie relativ lange Fruchtstiele gekennzeichnet.
Lebermoose im Bernstein 1
Authors: Grolle Riclef
Published: August 2010

Aus dem baltischen Bernstein werden an Hand der CASPARY'schen Originale Cephaloziella dimorpha (CASPARY) comb. nov. ( Jungermannia dimorpha CASPARY) und Bazzania polyodus (CASPARY) comb. nov. ( Lophocolea polyodus CASPARY) eingehend beschrieben und abgebildet. Die von CASPARY angegebene Dimorphie von C. dimorpha beruht auf der Verkennung eines apikalen Andröziums. C. dimorpha ist der erste paläontologische Nachweis der Cephaloziellaceae und sehr nah verwandt mit rezenten Arten in Mitteleuropa. Aufgrund der oberschlächtigen Blätter kann B. polyodus nicht zu den Lophocoleaceae gehören, für die damit die einzige paläontologische Angabe zu streichen ist. B. polyodus ist ein isoliertes Taxon ohne nähere Verwandte in Europa oder den Tropen. Sie ist der erste paläontologische Nachweis der Lepidoziaceae.
Über Markflecke im Holz kubanischer Baumarten
Authors: Süss Herbert , Vales Miguel A.
Published: August 2010

Für Kuba erstmalig wird das Vorkommen von Kambium‐Minierern der Gattung Phytobia Lioy (Agromyzidae, Diptera) durch Markflecke im Holz von Guazuma ulmifolia Lam. (Sterculiaceae) und Catalpa punctata Griseb. (Bignoniaceae) nachgewiesen. Von beiden Arten wird die Größe, Anordnung und Verteilung sowie die Anatomie der Fraßgänge (Markflecke) beschrieben. Im Holz von Catalpa punctata waren Markflecke bisher unbekannt.
Leaf architecture in relation to taxonomy: Ipomoea L.
Authors: Raya Rao S. Shanmukha , Leela M.
Published: August 2010

Architectural features of the leaf in fourteen species of Ipomoea have been studied. The leaves are simple or palmately compound. The major veination pattern conforms either to pinnate brochidodromous or actinodromous type. The leaf shape, apex, base, number of areoles and vein endingy entering the areoles are species specific. The highest degree of vein order is upto 6°. Vein endings exhibit conventional tracheids along with dilated tracheids. Bundle sheats cells ensheath all categories of veins. Based on these characters a key is prepared for the identification of the species investigated.
Charakteristika der Großpilzflora Vietnams
Authors: Kiet Trinh Tam
Published: August 2010

Auf der Grundlage der Untersuchungen des Autors seit 1963 und anderer seit 1890 wurden 829 Großpilzarten für Vietnam nachgewiesen, und zwar Myxomycota (19 Arten), Zygomycota (5 Arten), Ascomycota (86 Arten) und Basidiomycota (743 Arten). 519 Arten sind neu für das Territorium. Die Charakteristika der Großpilzflora Vietnams werden dargestellt und mit der Mykoflora Mitteleuropas verglichen. Einige ökologische Gruppen wie holzbewohnende, terrestrische, saprophytische, parasitische und symbiotische Pilze werden diskutiert. Phalloide, lumineszierende Pilze, „Pilzgärten”︁, eßbare und pharmazeutisch genutzte Pilze und andere werden genannt.
Numerical methods for determine the equilibrium point's stability of multidimensional nonlinear dynamic system
Authors: Junliang Wu , Pingping Zhang , Yong Wang
Published: August 2010

This work is concerned with the use of new nunumerical methods to establish some new criteria to determine the equilibrium point's stability of a multidimensional nonlinear dynamic system. Copyright © 2010 John Wiley & Sons, Ltd.
Specific attentional impairments and complex visual hallucinations in eye disease
Authors: Graham G , Dean J , Mosimann UP , Colbourn C , Dudley R , Clarke M , Collerton D
Published: August 2010

Objective

To test the prediction by the Perception and Attention Deficit (PAD) model of complex visual hallucinations that cognitive impairment, specifically in visual attention, is a key risk factor for complex hallucinations in eye disease.

Methods

Two studies of elderly patients with acquired eye disease investigated the relationship between complex visual hallucinations (CVH) and impairments in general cognition and verbal attention (Study 1) and between CVH, selective visual attention and visual object perception (Study 2). The North East Visual Hallucinations Inventory was used to classify CVH.

Results

In Study 1, there was no relationship between CVH (n = 10/39) and performance on cognitive screening or verbal attention tasks. In Study 2, participants with CVH (n = 11/31) showed poorer performance on a modified Stroop task (p < 0.05), a novel imagery‐based attentional task (p < 0.05) and picture (p < 0.05) but not silhouette naming (p = 0.13) tasks. Performance on these tasks correctly classified 83% of the participants as hallucinators or non‐hallucinators.

Conclusions

The results suggest that, consistent with the PAD model, complex visual hallucinations in people with acquired eye disease are associated with visual attention impairment. Copyright © 2010 John Wiley & Sons, Ltd.
CENTS: Cortical enhanced neonatal tissue segmentation
Authors: Shi Feng , Shen Dinggang , Yap Pew‐Thian , Fan Yong , Cheng Jie‐Zhi , An Hongyu , Wald Lawrence L. , Gerig Guido , Gilmore John H. , Lin Weili
Published: August 2010

The acquisition of high‐quality magnetic resonance (MR) images of neonatal brains is largely hampered by their characteristically small head size and insufficient tissue contrast. As a result, subsequent image processing and analysis, especially brain tissue segmentation, are often affected. To overcome this problem, a dedicated phased array neonatal head coil is utilized to improve MR image quality by augmenting signal‐to‐noise ratio and spatial resolution without lengthening data acquisition time. In addition, a specialized hybrid atlas‐based tissue segmentation algorithm is developed for the delineation of fine structures in the acquired neonatal brain MR images. The proposed tissue segmentation method first enhances the sheet‐like cortical gray matter (GM) structures in the to‐be‐segmented neonatal image with a Hessian filter for generation of a cortical GM confidence map. A neonatal population atlas is then generated by averaging the presegmented images of a population, weighted by their cortical GM similarity with respect to the to‐be‐segmented image. Finally, the neonatal population atlas is combined with the GM confidence map, and the resulting enhanced tissue probability maps for each tissue form a hybrid atlas is used for atlas‐based segmentation. Various experiments are conducted to compare the segmentations of the proposed method with manual segmentation (on both images acquired with a dedicated phased array coil and a conventional volume coil), as well as with the segmentations of two population‐atlas‐based methods. Results show the proposed method is capable of segmenting the neonatal brain with the best accuracy, and also preserving the most structural details in the cortical regions. Hum Brain Mapp, 2011. © 2010 Wiley‐Liss, Inc.
Predictive value of high Ki‐67 expression in stage I oral squamous cell carcinoma specimens after primary surgery
Authors: Freudlsperger Christian , Rohleder Sandra E. , Reinert Siegmar , Hoffmann Juergen
Published: August 2010

Background

Until now prognostic evaluation for patients with oral squamous cell carcinoma (OSCC) remains difficult. Thus, the aim of the present study was to ascertain the value of Ki‐67 expression in predicting locoregional recurrence in OSCC.

Methods

In a large, homogeneous study population consisting of 166 patients with OSCC exclusively treated with primary surgery, expression of Ki‐67 was investigated by immunohistochemistry.

Results

We report that high proliferation significantly correlated to a higher risk of locoregional recurrence in stage I OSCC patients (p = .029). Carcinomas with a Ki‐67 labeling index above the median showed a mean time to recurrence of 42 months, whereas mean time to recurrence was 55 months for those tumors below the median (p = .017).

Conclusions

This study provides the evidence of a predictive value of Ki‐67 expression in stage I OSCC. Therefore, Ki‐67 expression level could be used to identify a subgroup of surgically treated patients with stage I OSCC who might benefit from treatment intensification. © 2010 Wiley Periodicals, Inc. Head Neck, 2011
Frequent Multiple Hepatitis C Virus Infections Among Injection Drug Users in a Prison Setting
Authors: Pham Son T. , Bull Rowena A. , Bennett James M. , Rawlinson William D. , Dore Gregory J. , Lloyd Andrew R. , White Peter A.
Published: August 2010

Recent data indicate that multiple hepatitis C virus (HCV) infections (mixed infection, superinfection, and reinfection) are common among injection drug users (IDUs). In this study, we identified and characterized multiple HCV infection episodes among HCV-seronegative IDU prison inmates (n = 488) enrolled in the Hepatitis C Incidence and Transmission Study cohort. Incident HCV infection with detectable HCV RNA was identified in 87 subjects, 48 of whom completed additional follow-up to screen for reinfection or superinfection. All HCV RNA–detectable samples were tested for multiple infection through a series of specifically designed nested reverse-transcription polymerase chain reaction (nRT-PCR) with sequencing and HCV RNA level measurement. Sequencing revealed that 22 of 87 (25.3%) subjects were infected by two or more viruses. Nine (10.3%) subjects were designated as prevalent cases of incident mixed infection, because two distinct HCV strains were detected at the first viremic time point. Fifteen further cases of multiple HCV infection (superinfection or reinfection) were identified, two of which also showed baseline incident mixed infections. The incidence of new HCV infection (superinfection and reinfection) during follow-up was 40/100 person-years (95% confidence interval, 33-44/100 person-years). Spontaneous clearance of viruses from one subtype and persistence of the other subtype after mixed infection was observed in eight subjects. In these subjects, the virus with higher HCV RNA levels superseded the other.

Conclusion:

This study comprehensively analyzed frequent multiple HCV infections in a high-risk cohort and provides further insight into infection dynamics and immunity after exposure to variant viral strains. The data presented suggest that HCV RNA levels play an important role in viral competition. (Hepatology 2010;52:1564-1572)
Interactions between subgrid‐scale resolution, feature representation and grid‐scale resolution in flood inundation modelling
Authors: Yu D. , Lane S. N.
Published: August 2010

Numerical modelling of flood inundation over large and complex floodplains often requires mesh resolutions coarser than the structural features (e.g. buildings) that are known to influence the inundation process. Recent research has shown that this mismatch is not well represented by conventional roughness treatments, but that finer‐scale features can be represented through porosity‐based subgrid‐scale treatments. This paper develops this work by testing the interactions between feature representation, subgrid‐scale resolution and mesh resolution. It uses as the basis for this testing a 2D diffusion‐based flood inundation model which is applied to a 2004 flood event in a topologically complex upland floodplain in northern England. This study formulated simulations with different grid mesh resolution and subgrid mesh ratio. The sensitivity of the model to mesh resolution and roughness specification was investigated. Model validation and verification suggest that the subgrid treatment with higher subgrid mesh ratio can give much improved predictions of flood propagation, in particular, in terms of the predicted water depth. This study also highlighted the limitation of using at‐a‐point in time inundation extent for validation of flood models of this type. Copyright © 2010 John Wiley & Sons, Ltd.
Irrigation impact on annual water balance of the oases in Tarim Basin, Northwest China
Authors: Han Songjun , Hu Heping , Yang Dawen , Liu Qunchang
Published: August 2010

By taking the sum of annual precipitation and lateral water input (in which irrigation water withdrawal is the main component) for water availability, the Budyko hypothesis and Fu's formula derived from it was extended to the study of oases in the Tarim Basin, Northwest China. For both long‐term (multi‐year) and annual values on water balances in the 26 oases subregions, the extended Fu's formula was confirmed. Regional patterns on water balance on the 26 oases subregions were related to change in land‐use types due to increased area for irrigation. Moreover, an empirical formula for the parameter was established to reflect the influences of change in land use on water balance. The extended Budyko framework was employed to evaluate the impact of irrigation variability on annual water balance. According to the multi‐year mean timescale, variabilities in actual evapotranspiration in the oases were mainly controlled by variability in irrigation water withdrawal rather than potential evapotranspiration. The influences of variability on potential evapotranspiration became increasingly apparent together with increases in irrigation water withdrawal. Copyright © 2010 John Wiley & Sons, Ltd.
Adrenocortical hypertrophy: establishing cause and toxicological significance
Authors: Harvey Philip W. , Sutcliffe Catherine
Published: August 2010

The primary cause of adrenocortical hypertrophy is increased adrenocorticotrophic hormone (ACTH) stimulation. In toxicology studies, such a condition can arise as a result of the stress response, but it may also occur due to deficient glucocorticoid feedback regulation of ACTH due to toxicity to the adrenal cortex. This latter condition is defined as adrenocortical insufficiency and represents a serious adverse toxic effect on the function of the adrenal cortex. Adrenocortical hypertrophy may occur in the absence of other adrenocortical lesions such that a toxicopathological mechanism is not obvious, for example by pharmacological inhibition of steroidogenesis at the biochemical level. This review discusses the different aetiological factors and mechanisms producing adrenocortical hypertrophy. The need for further evidence in ascribing findings to stress is discussed, as is a protocol for establishing differential diagnoses between stress‐induced and toxicity‐induced adrenocortical hypertrophy, which is useful in cases where there are no other histopathological lesions in the adrenal cortex. It is concluded that all cases of adrenocortical hypertrophy require further investigation or evidence to ascribe such findings to either stress or adrenocortical inhibition/insufficiency, and that all cases of adrenocortical insufficiency (whether due to a histopathological lesion or reversible pharmacological enzyme inhibition) represent a serious adverse effect that must be properly considered in toxicological risk assessment. Copyright © 2010 John Wiley & Sons, Ltd.
Mutagenicity and genotoxicity of PM2.5 issued from an urbano‐industrialized area of Dunkerque (France)
Authors: André V. , Billet S. , Pottier D. , Le Goff J. , Pottier I. , Garçon G. , Shirali P. , Sichel F.
Published: August 2010

Epidemiological studies have demonstrated the link between chronic exposure to particulate matter (PM), especially particles with an aerodynamic diameter lesser than 2.5 µm (PM2.5), and lung cancer. Mechanistic investigations focus on the contribution of the various genotoxicants adsorbed onto the particles, and more particularly on polycyclic aromatic hydrocarbons or nitroaromatics. Most of the previous studies dealing with genotoxic and/or mutagenic measurements were performed on organic extracts obtained from PM2.5 collected in polluted areas. In contrast, we have evaluated genotoxic and mutagenic properties of urbano‐industrial PM2.5 (PM) collected in Dunkerque (France). Thermally desorbed PM2.5 (dPM) was also comparatively studied. Suspensions of PM and dPM (5–50 µg per plate) were tested in Salmonella tester strains TA98, TA102 and YG1041 ± S9mix. Significant mutagenicity was observed for PM in YG1041 ± S9 mix. In strain TA102 – S9mix, a slight, but not significant dose–response increase was observed, for both PM and dPM. Genotoxic properties of PM and dPM were evaluated by the measurement of (1) 8‐OHdG in A549 cells and (2) bulky DNA adducts on A549 cells and on human alveolar macrophages (AMs) in primary culture. A dose‐dependant formation of 8‐OHdG adducts was observed on A549 cells for PM and dPM, probably mainly attributed to the core of the particles. Bulky DNA adducts were observed only in AMs after exposure to PM and dPM. In conclusion, using relevant exposure models, suspension of PM2.5 induces a combination of DNA‐interaction mechanisms, which could contribute to the induction of lung cancer in exposed populations. Copyright © 2010 John Wiley & Sons, Ltd.
Removal of thallium by deferasirox in rats as biological model
Authors: Saljooghi Amir Sh. , Fatemi S. Jamiladin
Published: August 2010

The present research aimed to characterize the potential efficiency of deferasirox in removing thallium after its administration for 30 days following two dose levels of 20 and 160 μm of thallium (III) chloride to male Wistar rats every day. After thallium administration some abnormal clinical signs such as red staining around the eyes, greenish mottling on the liver, weakness, loss of hair and weight, were observed in animals. Deferasirox was given orally to different groups of rats for a period of one week immediately after thallium administration. After chelation therapy, animals were killed by exsanguination from the abdominal aorta, and then thallium and iron concentrations in various tissues were determined by standard addition method. The chelation therapy results showed that deferasirox was able to remove thallium ions from the body and clinical symptoms were also reduced. Copyright © 2010 John Wiley & Sons, Ltd.
BMD regulation on mouse distal chromosome 1, candidate genes, and response to ovariectomy or dietary fat
Authors: Beamer Wesley G , Shultz Kathryn L , Coombs Harold F , DeMambro Victoria E , Reinholdt Laura G , Ackert-Bicknell Cheryl L , Canalis Ernesto , Rosen Clifford J , Donahue Leah Rae
Published: August 2010

The distal end of mouse chromosome 1 (Chr 1) harbors quantitative trait loci (QTLs) that regulate bone mineral density (BMD) and share conserved synteny with human chromosome 1q. The objective of this article was to map this mouse distal Chr 1 region and identify gene(s) responsible for BMD regulation in females. We used X-ray densitometry [ie, dual-energy X-ray Absorptiometry (DXA), micro–computed tomography (µCT), and peripheral quantitative computed tomography (pQCT)] to phenotype a set of nested congenic strains constructed from C57BL/6BmJ (B6/Bm) and C3H/HeJ (C3H) mice to map the region associated with the BMD QTL. The critical region has been reduced to an interval of 0.152 Mb that contributes to increased BMD when C3H alleles are present. Histomorphometry and osteoblast cultures indicated that increased osteoblast activity was associated with increased BMD in mouse strains with C3H alleles in this critical region. This region contains two genes, Aim2, which binds with cytoplasmic dsDNA and results in apoptosis, and AC084073.22, a predicted gene of unknown function. Ovariectomy induced bone loss in the B6/Bm progenitor and the three congenic strains regardless of the alleles present in the critical BMD region. High dietary fat treatment (thought to suppress distal Chr 1 QTL for BMD in mice) did not induce bone loss in the congenics carrying C3H alleles in the critical 0.152 Mb carrying the AIM2 and AC084073.22 genes. Gene expression studies in whole bone of key congenics showed differential expression of AC084073.22 for strains carrying B6/Bm versus C3H alleles but not for Aim2. In conclusion, our data suggest that osteoblasts are the cellular target of gene action and that AC084073.22 is the best candidate for female BMD regulation in the distal region of mouse Chr 1. © 2011 American Society for Bone and Mineral Research.
Improvement in cytoarchitectonic mapping by combining electrodynamic modeling with local orientation in high‐resolution images of the cerebral cortex
Authors: Schmitt Oliver , Birkholz Harald
Published: August 2010

To detect changes of cortical cytoarchitectonics, digital images of cortical laminations are analyzed. Cortical regions are transformed into a rectangular grid for subsequent evaluations. Transformations are realized by stepwise scanning using perpendicular testlines. 3D cytoarchitectonic data of the human brain at a histological resolution are not available and 2D sections deliver partial information only. The problem is to find an optimal scanning‐technique that introduces a minimum of distortions and noise by the transformation of the curvilinear cortex to a rectangular presentation. In the past this was solved by constructing testlines dependent on the outlined cortical contours only. An advanced approach was to model the contours as electrically charged surfaces and to use the resulting field lines as testlines. However, local information of cell distributions were not considered. Hence a novel hybrid approach was developed which is able to construct significantly better testlines in cortical images with mixtures of columnar rich (local orientation rich) and orientation poor parts of strongly curved and large regions of the cerebral cortex. The novel hybrid approach is based on the computer vision methods such as the structure tensor and constrained anisotropic diffusion. In addition, the introduction of projective transformations yields a significant improvement of cortical fingerprints, thereby offering the possibility for detecting weakly pronounced regions of cytoarchitectonic transitions. The statistical evaluation of the novel hybrid approach confirms robustness. This technique can be generalized and applied to different types of cerebral cortex with any kind and amount of local orientation information. Microsc. Res. Tech. 2010. © 2010 Wiley‐Liss, Inc.
Radiosynthesis of N5‐[18F]fluoroacetylornithine (N5‐[18F]FAO) for PET imaging of ornithine decarboxylase (ODC) in malignant tumors
Authors: Turkman Nashaat , Gelovani Juri G. , Alauddin Mian M.
Published: August 2010

Polyamines are naturally occurring polycations derived from amino acids via decarboxylation by ornithine decarboxylase (ODC). Ornithine is a substrate for ODC; decarboxylation of ornithine is inhibited by difluoromethylornithine (DFMO) and its derivatives. Polyamine contents are increased in many epithelial cancers, including breast cancer, melanoma, and prostate cancer. In order to image and measure the levels of ODC expression in malignant tumors, we have synthesized a derivative of ornithine, N5‐[18F]fluoroacetylornithine (N5‐[18F]FAO), for use in positron emission tomography. The precursor compound N2‐Boc‐N5‐bromoacetylornithine‐t‐butyl ester 2 was synthesized from 5‐amino‐2‐(tert‐butoxycarbonylamino)pentanoic acid, which was reacted with bromoacetyl chloride followed by esterification with tert‐butyl‐2,2,2‐trichloroacetamidate. Fluorination of the precursor produced a fluoro‐derivative, which was hydrolyzed in acid to obtain the desired compound, N5‐fluoroacetylornithine. The radiosynthesis of N5‐[18F]FAO was accomplished by radiofluorination of 2 with n‐Bu4N[18F], followed by high‐performance liquid chromatography (HPLC) purification and then by acid hydrolysis. The radiochemical yield was 6–10% (decay corrected) with an average of 8% (n=10) at the end of synthesis. The radiochemical purity was >99%, and specific activity was >1500 mCi/µmol. The synthesis time was 95–100 min from the end of bombardment. Copyright © 2010 John Wiley & Sons, Ltd.
Synthesis of triphenylsilyl[14C2]acetylene for use in a Sonogashira reaction
Authors: Elmore Charles S. , Dorff Peter N.
Published: August 2010

Silylacetylenes are useful coupling partners for aromatic halides in the Sonogashira reaction and a C‐14 labeled version of this useful synthon would allow ready access to a wide variety of arylalkynes. Ca14C2 was converted to triphenylsilyl[14C2]acetylene using two related routes in 65% yield, and the resulting [14C2]acetylene was coupled with an aryl halide to give the target triphenylsilylarylacetylene (2) in 40% yield. Copyright © 2010 John Wiley & Sons, Ltd.
Design and synthesis of novel fluorescently labelled nucleosides
Authors: Zheng Jin Yun , Feng Xiang Ming , Zhang Shu Feng , Zhao Yu Fen
Published: August 2010

A series of novel 5′‐labelled uridine with fluorophores: N‐alkylcarbazole, alkyloxynaphthalene and alkylfluorene were synthesized through H‐phosphonate by Arbuzov reaction, and were characterized by using 1H NMR, 31P NMR and ESI‐MS analysis. The fluorescence spectra of all the compounds in solution and solid powder were described. The experimental results showed that the fluorescence emission intensity of 5′‐labelled uridine is very sensitive to solvents. Copyright © 2010 John Wiley & Sons, Ltd.
Angiotensin‐I converting enzyme inhibitory and antioxidant activities of peptide fractions extracted by ultrafiltration of cowpea Vigna unguiculata hydrolysates
Authors: Segura Campos Maira R , Chel Guerrero Luis A , Betancur Ancona David A
Published: August 2010

BACKGROUND: Enzymatic proteolysis of food proteins is used to produce peptide fractions with the potential to act as physiological modulators. Fractionation of these proteins by ultrafiltration results in fractions rich in small peptides with the potential to act as functional food ingredients. The present study investigated the angiotensin‐I converting enzyme (ACE‐I) inhibitory and antioxidant activities for hydrolysates produced by hydrolyzing Vigna unguiculata protein extract as well as ultrafiltered peptide fractions from these hydrolysates.

RESULTS: Alcalase®, Flavourzyme® and pepsin–pancreatin were used to produce extensively hydrolyzed V. unguiculata protein extract. Degree of hydrolysis (DH) differed between the enzymatic systems and ranged from 35.7% to 58.8%. Fractionation increased in vitro biological activities in the peptide fractions, with IC50 (hydrolysate concentration in µg protein mL−1 required to produce 50% ACE inhibition) value ranges of 24.3–123 (Alcalase hydrolysate, AH), 0.04–170.6 (Flavourzyme hydrolysate; FH) and 44.7–112 (pepsin–pancreatin hydrolysate, PPH) µg mL−1, and TEAC (Trolox equivalent antioxidant coefficient) value ranges of 303.2–1457 (AH), 357.4–10 211 (FH) and 267.1–2830.4 (PPH) mmol L−1 mg−1 protein.

CONCLUSION: The results indicate the possibility of obtaining bioactive peptides from V. unguiculata proteins by means of a controlled protein hydrolysis using Alcalase®, Flavourzyme® and pepsin–pancreatin. The V. unguiculata protein hydrolysates and their corresponding ultrafiltered peptide fractions might be utilized for physiologically functional foods with antihypertensive and antioxidant activities. Copyright © 2010 Society of Chemical Industry
Monodispersed Magnetic Polystyrene Beads with Excellent Colloidal Stability and Strong Magnetic Response
Authors: Niu Mu , Du Meihong , Gao Zhenyu , Yang Chunhui , Lu Xianyong , Qiao Ruirui , Gao Mingyuan
Published: August 2010

Monodispersed polystyrene beads incorporated with Fe3O4 nanoparticles are prepared via dispersion polymerization. The resultant magnetic beads present well‐defined composite structures, excellent colloidal stability, and strong magnetic response. The formation mechanism for the monodispersed composite beads, incorporated with preformed Fe3O4 nanocrystals, was investigated. The potential applications of the monodispersed magnetic beads in bacteria capturing were demonstrated. After being coated with anti‐Salmonella CSA‐1 antibody, the magnetic beads show capturing efficiencies of >99.4% in isolating Salmonella sp.

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Involvement of Akt/NF‐κB pathway in N6‐isopentenyladenosine‐induced apoptosis in human breast cancer cells
Authors: Laezza Chiara , Malfitano Anna M. , Di Matola Tiziana , Ricchi Paolo , Bifulco Maurizio
Published: August 2010

N6‐isopentenyladenosine (i6A) inhibits the tumor cell growth by inducing cell apoptosis in various cancer cell lines. However, little is known regarding the mechanisms by which the drug induces cell apoptosis. In this study, we further explored the molecular mechanisms of i6A as an anticancer agent on a human breast cancer cell line MDA MB 231. Treatment with i6A decreased the cell proliferation of MDA MB 231 cells in a dose‐dependent manner by arresting the cells at G0/G1 phase. This effect was strongly associated with concomitant decrease in the level of cyclin D1, cyclin E, cdk2, and increase of p21waf1 and p27kip. In addition i6A also induced apoptotic cell death by increasing the expression of Bax, and decreasing the levels of Bcl‐2 and Bcl‐xL, and subsequently triggered mitochondria apoptotic pathway (release of cytochrome c and activation of caspase‐3). We observed that i6A suppressed the nuclear factor kappaB (NF‐κB) pathway and inhibited the Akt activation. The results of this study indicate that i6A decreases cell proliferation and induces apoptotic cell death in human breast cancer cells, possibly by decreasing signal transduction through the Akt/NF‐κB cell survival pathway. © 2010 Wiley‐Liss, Inc.
Plasma selenium is positively related to performance in neurological tasks assessing coordination and motor speed
Authors: Shahar Avner , Patel Kushang V. , Semba Richard D. , Bandinelli Stefania , Shahar Danit R. , Ferrucci Louigi , Guralnik Jack M.
Published: August 2010

Parkinson's disease (PD) is a degenerative process affecting the striato nigral system (SN). Its etiology, although obscure, may involve oxidative damage. Selenium, an antioxidant, was shown to protect the SN in animal models. In the current study, we investigate the association between plasma selenium concentrations and the presence of “soft” neurological signs related to the SN. Plasma selenium concentration was assessed in participants of age ≥65 years in the InCHIANTI study, a population‐based cohort study in Tuscany, Italy. PD was defined based on standard criteria. “Soft” neurological signs were ascertained by physical examination. A total of 1,012 participants were included. No association was found between the presence of PD and plasma selenium. There was, however, a strong association between plasma selenium and timed performance‐based assessments. Lower levels of selenium were significantly associated withdecreased performance in neurological tests of coordination among older adults. Prospective studies are needed to further investigate the effects of selenium on SN dysfunction. © 2010 Movement Disorder Society
From single‐pulsed field gradient to double‐pulsed field gradient MR: gleaning new microstructural information and developing new forms of contrast in MRI
Authors: Shemesh Noam , Özarslan Evren , Komlosh Michal E. , Basser Peter J. , Cohen Yoram
Published: August 2010

One of the hallmarks of diffusion NMR and MRI is its ability to utilize restricted diffusion to probe compartments much smaller than the excited volume or the MRI voxel, respectively, and to extract microstructural information from them. Single‐pulsed field gradient (s‐PFG) MR methodologies have been employed with great success to probe microstructures in various disciplines, ranging from chemistry to neuroscience. However, s‐PFG MR also suffers from inherent shortcomings, especially when specimens are characterized by orientation or size distributions: in such cases, the microstructural information available from s‐PFG experiments is limited or lost. Double‐pulsed field gradient (d‐PFG) MR methodology, an extension of s‐PFG MR, has attracted attention owing to recent theoretical studies predicting that it can overcome certain inherent limitations of s‐PFG MR. In this review, we survey the microstructural features that can be obtained from conventional s‐PFG methods in the different q regimes, and highlight its limitations. The experimental aspects of d‐PFG methodology are then presented, together with an overview of its theoretical underpinnings and a general framework for relating the MR signal decay and material microstructure, affording new microstructural parameters. We then discuss recent studies that have validated the theory using phantoms in which the ground truth is well known a priori, a crucial step prior to the application of d‐PFG methodology in neuronal tissue. The experimental findings are in excellent agreement with the theoretical predictions and reveal, inter alia, zero‐crossings of the signal decay, robustness towards size distributions and angular dependences of the signal decay from which accurate microstructural parameters, such as compartment size and even shape, can be extracted. Finally, we show some initial findings in d‐PFG MR imaging. This review lays the foundation for future studies, in which accurate and novel microstructural information could be extracted from complex biological specimens, eventually leading to new forms of contrast in MRI. Copyright © 2010 John Wiley & Sons, Ltd.
Simplified immersed interface methods for elliptic interface problems with straight interfaces
Authors: Feng Xiufang , Li Zhilin
Published: August 2010

In this article, we propose simplified immersed interface methods for elliptic partial/ordinary differential equations with discontinuous coefficients across interfaces that are few isolated points in 1D, and straight lines in 2D. For one‐dimensional problems or two‐dimensional problems with circular interfaces, we propose a conservative second‐order finite difference scheme whose coefficient matrix is symmetric and definite. For two‐dimensional problems with straight interfaces, we first propose a conservative first‐order finite difference scheme, then use the Richardson extrapolation technique to get a second‐order method. In both cases, the finite difference coefficients are almost the same as those for regular problems. Error analysis is given along with numerical example. © 2010 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 28: 188–203, 2012
A discontinuous finite volume element method for second‐order elliptic problems
Authors: Bi Chunjia , Liu Mingming
Published: August 2010

In this article, we propose a new discontinuous finite volume element (DFVE) method for the second‐order elliptic problems. We treat the DFVE method as a perturbation of the interior penalty method and get a superapproximation estimate in a mesh dependent norm between the solution of the DFVE method and that of the interior penalty method. This reveals that the DFVE method is much closer to the interior penalty method than we have known. By using this superapproximation estimate, we can easily get the optimal order error estimates in the L2 ‐norm and in the maximum norms of the DFVE method.© 2010 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 28: 425–440, 2012
Multicentric osteosarcoma associated with DISH, in a 19th century burial from England
Authors: Ortner Donald J. , Ponce Paola , Ogden Alan , Buckberry Jo
Published: August 2010

Osteosarcoma is a rare type of malignant neoplasm that is most frequent in adolescents and young adults although it can develop at any age. It can metastasize from a primary site in bone to other bones and soft tissues. Usually the disorder causes a single bone‐forming lesion (unicentric) but some cases have multicentric, bone‐forming lesions. Some of these lesions develop at different sites at different times. In a second variant of multicentric osteosarcoma, synchronous bone‐forming lesions develop at multiple sites. Distinguishing between these two types of multicentric osteosarcoma is challenging in a clinical context and the criteria for doing so are unlikely to be met in an archaeological burial. Wolverhampton burial HB 39 was excavated from an early‐nineteenth century cemetery site in England. It consists of the incomplete skeleton of an adult male of at least 45 years of age with multicentric osteosarcoma. The individual represented by this burial also had diffuse idiopathic skeletal hyperostosis (DISH). Three of the bone‐forming lesions associated with osteosarcoma developed on the bony outgrowths related to DISH. Copyright © 2010 John Wiley & Sons, Ltd.
Synthesis and characterization of organo‐soluble polyamides containing triaryl imidazole pendant and ether linkage moieties: thermal, photophysical, and chemiluminescent properties
Authors: Ghaemy M. , Nasab S. M. Amini
Published: August 2010

A new symmetrical diamine monomer containing a triaryl imidazole pendant group was successfully synthesized by the nucleophilic substitution of hydroquinone with the synthesized 2‐(2‐chloro‐5‐nitrophenyl)‐4, 5‐diphenyl‐1H‐imidazole (I). A series of novel polyamides were prepared from the diamine monomer and various aliphatic and aromatic dicarboxylic acids via phosphorylation polyamidation. These polyamides are readily soluble in many organic solvents; their inherent viscosities ranged from 0.68 to 0.89 dl/g and gave tough and flexible films by solution‐casting. They had useful levels of thermal stability associated with relatively high Tgs (186–278°C), 10% weight loss temperatures in the range of 355–482°C, and char yields at 600°C in air up to 67%. All the polyamides have fluorescence emission in dilute (0.2 g/dl) DMAc solution with maxima at 425–495 nm and with the quantum yields in the range 14–28%. The chemiluminescence activity of polyamides was also studied in the presence of peroxyoxalate. Copyright © 2010 John Wiley & Sons, Ltd.
Solventless silicone hybrids based on polyhedral oligomeric silsesquioxane and hyperbranched polysiloxane for vacuum pressure impregnation process
Authors: Zhang Beijing , Gu Aijuan , Liang Guozheng , Hu Jiang‐tao , Zhuo Dongxian , Yuan Li
Published: August 2010

A novel kind of solventless silicone hybrids (SSiH) containing branched poly(methylphenylvinylsiloxane) (PMPVSi), end‐capped hydrogen‐functionalized hyperbranched polysiloxane (EHFHPSi), and octavinyl‐polyhedral oligomeric silsesquioxane (OVPOS) was developed through a hydrosilylation reaction. Each of the three basic components was synthesized by harmless and recyclable methods. The new hybrids are considerably suitable for vacuum pressure impregnation process, and can serve as an excellent class C insulating material. The effect of differing stoichiometries of OVPOS and EHFHPSi on the performance of cured hybrids is discussed. Results show that SSiH hybrids possess excellent dielectric and thermal properties as well as low viscosity. The reduction in the dielectric constant and the improvement of thermal property of SSiH hybrids can be explained by the unique structure and morphology of hybrids resulting from the presence of OVPOS and EHFHPSi. The novel silicone hybrids exhibit great potential to be used for many cutting‐edge industries, especially the microelectronic and insulation fields. Copyright © 2010 John Wiley & Sons, Ltd.