bluuebunny/crossref_metadata_2025 huggingface dataset:
Role of extracellular matrix proteins and their receptors in the development of the vertebrate neuromuscular junction
Authors: Singhal Neha , Martin Paul T.
Published: July 2011

The vertebrate neuromuscular junction (NMJ) remains the best‐studied model for understanding the mechanisms involved in synaptogenesis, due to its relatively large size, its simplicity of patterning, and its unparalleled experimental accessibility. During neuromuscular development, each skeletal myofiber secretes and deposits around its extracellular surface an assemblage of extracellular matrix (ECM) proteins that ultimately form a basal lamina. This is also the case at the NMJ, where the motor nerve contributes additional factors. Before most of the current molecular components were known, it was clear that the synaptic ECM of adult skeletal muscles was unique in composition and contained factors sufficient to induce the differentiation of both pre‐ and postsynaptic membranes. Biochemical, genetic, and microscopy studies have confirmed that agrin, laminin (221, 421, and 521), collagen IV (α3‐α6), collagen XIII, perlecan, and the ColQ‐bound form of acetylcholinesterase are all synaptic ECM proteins with important roles in neuromuscular development. The roles of their many potential receptors and/or binding proteins have been more difficult to assess at the genetic level due to the complexity of membrane interactions with these large proteins, but roles for MuSK‐LRP4 in agrin signaling and for integrins, dystroglycan, and voltage‐gated calcium channels in laminin‐dependent phenotypes have been identified. Synaptic ECM proteins and their receptors are involved in almost all aspects of synaptic development, including synaptic initiation, topography, ultrastructure, maturation, stability, and transmission. © 2011 Wiley Periodicals, Inc. Develop Neurobiol 71: 982‐1005, 2011
Brain activity associated with graphic emoticons. The effect of abstract faces in communication over a computer network
Authors: Yuasa Masahide , Saito Keiichi , Mukawa Naoki
Published: July 2011

In this paper, we describe the brain activities that are associated with graphic emoticons by using functional MRI (fMRI). We use various types of faces, from abstract to photorealistic, in computer network applications. A graphics emoticon is an abstract face in communication over a computer network. In this research, we created various graphic emoticons for the fMRI study and the graphic emoticons were classified according to friendliness and level of arousal. We investigated the brain activities of participants who were required to evaluate the emotional valence of the graphic emoticons (happy or sad). The experimental results showed that not only the right inferior frontal gyrus and the cingulate gyrus, but also the inferior and middle temporal gyrus and the fusiform gyrus, were found to be activated during the experiment. Furthermore, it is possible that the activation of the right inferior frontal gyrus and the cingulate gyrus is related to the type of abstract face. Since the inferior and middle temporal gyrus were activated, even though the graphic emoticons are static, we may perceive graphic emoticons as dynamic and living agents. Moreover, it is believed that text and graphics emoticons play an important role in enriching communication among users. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 177(3): 36–45, 2011; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21162
Molecular Rotors as Fluorescent Viscosity Sensors: Molecular Design, Polarity Sensitivity, Dipole Moments Changes, Screening Solvents, and Deactivation Channel of the Excited States
Authors: Zhou Fuke , Shao Jingyin , Yang Yubin , Zhao Jianzhang , Guo Huimin , Li Xiaolian , Ji Shaomin , Zhang Zongying
Published: July 2011

A library of new fluorescent molecular rotors (FMRs) for viscosity sensing was synthesized. The sensitivity of the fluorescence emission toward solvent viscosity and polarity was investigated by using UV/Vis absorption, fluorescence emission spectra, and theoretical calculations. For the new FMRs, red‐shifted emissions at 620 nm, Stokes shifts of 170 nm, and up to 40‐fold fluorescence enhancement upon increasing the viscosity of solvents were observed (cf. known FMRs with emissions at 491 nm, Stokes shift of 33 nm and fivefold emission enhancement). By using solvents with high viscosity but low polarity, for example, polyethylene glycol (PEG‐400) or dimethyl silicone oil, rotors previously identified as non‐FMRs with ethylene glycol/glycerol show FMR properties. We found triphenylamine (TPA)‐based rotors showed solvent‐polarity‐dependent emission, but also FMR properties. This is contrary to the known theory of FMRs. One of the TPA‐based rotors shows the highest x value of 0.88 (versus 0.6 for known FMRs). The emissive excited states of the FMRs proved to be locally excited (LE) states and twisted intramolecular charge‐transfer (TICT) states were identified as dark states through trifluoroacetic acid titration and DFT/time‐dependent DFT calculations, which show that the nonradiative decay channel of the excited FMRs is the rotation about the dicyanovinyl C=C double bonds in the S1 state, not rotation around C–C single bonds. Extension of the π conjugation of the rotors increases the rotation barrier around the C=C double bond in the S1 state (to ca. 50 kJ mol–1 or higher), thus the nonradiative channel is blocked and higher fluorescence quantum yields are observed for the new rotors. Our results will be useful for future design of FMRs as fluorescent viscosity sensors.
Magnesium oxide nanoparticles: Preparation, characterization, and uranium sorption properties
Authors: Camtakan Zeyneb , Erenturk Sema (Akyil) , Yusan Sabriye (Doyurum)
Published: July 2011

The objective of this work was to study the sorption of uranium (VI) ions on magnesium oxide (MgO) from aqueous solutions. The MgO has been prepared via hydroxide precipitation followed by thermal decomposition of the hydroxide. MgO was characterized by X‐ray powder diffraction, scanning electron microscope, and multipoint Brunauer, Emmett, and Teller. The relative importance of test parameters such concentration of adsorbate, pH, contact time, and temperature on adsorption performance of MgO for U(VI) ion were studied and the optimum sorption efficiency was found as 87.61 ± 3.10%. Desorption tests were also carried out and desorption efficiency was found as 100% with NH4Cl and NaNO3 solutions containing 0.1 M on a single step. Typical sorption isotherms (Freundlich and Dubinin‐Raduskevich) were determined for the mechanism of sorption process and thermodynamic constants (ΔH°, ΔS°, and ΔG°) were calculated as −8.738 kJ mol−1, −21.68 kJ mol−1, and 0.102 kJ mol−1 K−1, respectively. © 2011 American Institute of Chemical Engineers Environ Prog, 2011
A study of no conversion into No2 and N2O over Co3O4 catalyst
Authors: Ayoub Muhammad , Faisal Irfan Muhammad , Zuhairi Abdullah Ahmad
Published: July 2011

The catalytic activity of Co3O4 catalyst was examined in a differential reactor for converting NO to NO2 and N2O. It was observed that mostly NO was oxidized to NO2 rather than N2O over the catalyst at temperatures above 250°C in the presence of 5% oxygen and 10% water. The maximum conversion was 71% at 300°C. However, the presence of H2O slightly suppressed NO2 generation due to the occupation of active sites by H2O but no such effect was observed during N2O generation. At calcination temperature of 300°C, the maximum activity of the catalyst for NO conversion was observed due to the sintering of the catalyst at higher temperatures. In the presence of hydrocarbon, inhibition of NO conversion was also observed. This was due to the hydrocarbon competition with NO for the active sites of the catalyst. Moreover, on comparing with other workers, the activity of NO conversion over Co3O4 catalyst was found to be more selective towards NO2 generation at a wide range of temperatures resulting in less N2O generation. The activation energy (Ea) and pre‐exponential factor (Ao) values were found to be 37.7 kJ mol−1 and −7.26 ppm−2 s−1. © 2011 American Institute of Chemical Engineers Environ Prog, 2011
Dark fermentation of hydrogen from waste glycerol using hyperthermophilic eubacterium Thermotoga neapolitana
Authors: Ngo Tien Anh , Sim Sang Jun
Published: July 2011

Waste glycerol from bio‐diesel manufacturing is currently held to be a new, attractive, and abundant resource for future bio‐fuel. Bio‐hydrogen production via the fermentation route was examined for the first time from pure glycerol and discharged waste glycerol as the sole substrate by the hyperthermophilic eubacterium Thermotoga neapolitana. The bacterium, directly fermenting pure glycerol and crude waste glycerol in the medium, showed respective retarded growth and low H2 production 447 ± 22 mL H2 L−1 and 437 ± 21 mL H2 L−1. Attempting to improve the growth and H2 production, small amount (1.5 g L−1) of itaconic acid was added into the culture medium. In this case, H2 production from fermentation was approximately 620 ± 30 mL H2 L−1 for both pure glycerol and pre‐treated waste glycerol as main substrate, an increase of 36.6% compared with cultures grown without itaconic acid, respectively. Further optimization of the glycerol concentration and culture conditions revealed enhancements in growth, H2 production, and glycerol utilization. The H2 fermentation from waste glycerol is of potential importance as wastes from bio‐diesel processes can be utilized to produce bio‐hydrogen. © 2011 American Institute of Chemical Engineers Environ Prog, 2011
Evaluation of meteorological controls of reconstructed rockfall activity in the Czech Flysch Carpathians
Authors: Šilhán Karel , Brázdil Rudolf , Pánek Tomáš , Dobrovolný Petr , Kašičková Lucie , Tolasz Radim , Turský Ondřej , Václavek Marek
Published: July 2011

Rockfall is an important process in the final sculpturing of escarpments and scree slopes that originate in bedrock landslides in the Flysch Carpathians. The spatio‐temporal characteristics of rockfall activity were studied at four localities representative of old landslides in the highest part of the Czech Flysch Carpathians (Moravskoslezské Beskydy Mountains). Historical activity, chronology, and spatial context of rockfall activity were reconstructed using dendrogeomorphic techniques and rockfall rate index (RR). A total of 1132 increment cores from 283 trees growing in the rockfall transport and accumulation zones enabled the dating of 989 rockfall events. Reconstruction of a 78‐year‐long RR chronology suggests similar rockfall histories and trends at all study sites, indicating the existence of major common factors driving rockfall dynamics in the region. Temporal analysis and correlation of the RR series obtained with monthly mean temperatures, numbers of days with temperature transitions through 0 °C and monthly precipitation totals show that meteorological characteristics have evident but variable influence on rockfall activity. The most important factor is the effect of freeze–thaw cycles throughout the year, supplemented by low temperatures, especially during autumn. The influence of precipitation totals is of lesser importance. Copyright © 2011 John Wiley & Sons, Ltd.
The coupling status of alluvial fans and debris cones: a review and synthesis
Authors: Harvey Adrian M.
Published: July 2011

Alluvial fans and debris cones link two zones of the fluvial system (e.g. hillslope gully systems to stream channels; mountain catchment sediment source areas to main river systems or to sedimentary basins) and therefore have important coupling or buffering roles. These roles may be both functional and preservational. The functional role includes debris‐cone coupling, which controls sediment supply from hillslope gully systems to stream channels, influencing channel morphology. Coupling through larger alluvial fans, expressed by fanhead trenching, causes a distal shift in sedimentation zones, or when expressed by through‐fan trenching, causes complete sediment by‐pass. The preservational role stems from the fact that fans and cones are temporary sediment storage zones, and may preserve a record of source–area environmental change more sensitively than would sediments preserved further downsystem. Fan coupling mechanisms include distally‐induced coupling (basal scour, ‘toe cutting’, marginal incision) and proximally‐induced coupling (fanhead and midfan trenching). These mechanisms lead initially to partial coupling, either extending the immediate sediment source area to the stream system or shifting the focus of sedimentation distally. Complete coupling involves transmission of sediment from the feeder catchment through the fan environment into the downstream drainage or a sedimentary basin. The implications of coupling relate to downstream channel response, fan morphology, sedimentation patterns and vertical sedimentary sequences. Temporal and spatial scales of coupling are related, and with increasing scales the dominant controls shift from storm events to land cover to climatic and base‐level change and ultimately to the relationships between tectonics and accommodation space. Finally, future research challenges are identified. Modern dating techniques and sophisticated analysis of remotely sensed data can greatly improve our understanding of fan dynamics, and should lead to better cross‐scale integration between short‐term process‐based approaches and long‐term sedimentological applications, while maintaining high quality field‐based observations. Copyright © 2011 John Wiley & Sons, Ltd.
Xenobiotic-induced changes in the arginase activity of zebrafish (Danio rerio) eleutheroembryo
Authors: Fuentealba González Pablo , Llanos-Rivera Alejandra , Carvajal Baeza Nelson , Uribe Pérez Elena
Published: July 2011

The impact of xenobiotics in organisms at the biochemical level can be detected using specific or nonspecific biochemical markers. Activity of the enzyme arginase is used as a biochemical parameter of cell proliferation in mammals because of its importance in polyamine synthesis, which provides molecules for cellular growth and differentiation. Therefore, total arginase activity could indicate sublethal organism alterations induced by xenobiotics. In the present study, bioassays with early stages of Danio rerio were implemented using the pesticide malathion as a reference toxicant and a kraft pulp mill (KPM) effluent to assess their potential toxicity. The experimental design considered a 144-h static bioassay that involved incubation from an early 3-h postfertilization embryonic stage through to the eleutheroembryo stage. Growth variations and observations of organ development were evaluated and related to total arginase activity. The enzymatic activity in eleutheroembryo exposed to malathion exhibited a significant decrease at concentrations equal to or higher than 3 mg/L. Delays in the early development and morphometric parameters suggest metabolic depression in these conditions. A significant positive relationship between total arginase activity and eleutheroembryo development was observed, indicating that a decrease in total arginase activity might be related to sublethal alterations in eleutheroembryo growth. Bioassay results with KPM effluents resulted in a delay in organogenesis only in effluent concentrations of 100% and were related to a significant decrease in total arginase activity. In conclusion, total arginase activity has a higher sensitivity compared with morphological parameters in providing an early signal of the sublethal effects on early life stages of fish exposed to environmental stress. Environ. Toxicol. Chem. 2011;30:2285–2291. © 2011 SETAC
A moving mesh BGK scheme for multi‐material flows
Authors: Ni Guoxi , Jiang Song , Xu Xihua
Published: July 2011

In this paper, a moving mesh BGK scheme (MMBGK) for multi‐material flow computations is proposed. The basic idea of constructing the MMBGK is to couple the Lagrangian method, which tracks material interfaces and keeps the interfaces sharp, with a remapping‐free ALE‐type kinetic method within each single material region, where the kinetic method is based on the BGK (Bhatnagar–Gross–Krook) model. Within each single material region, a numerical flux formulation is developed on moving meshes from motion of microscope particles, and the mesh velocity is determined by requiring both mesh adaptation for accuracy and robustness, such that the grids are moving towards to the regions with high flow gradients in a way of diffusive mechanism (velocity) to adjust the distances between neighboring cells, thus increasing the numerical accuracy. To keep the sharpness of material interfaces, the Lagrangian velocity and flux are constructed at the interfaces only. Consequently, a BGK‐scheme‐based ALE‐type method (i.e., the MMBGK scheme) for multi‐material flows is constructed. Numerical examples in one and two dimensions are presented to illustrate the accuracy and robustness of the MMBGK scheme. Copyright © 2011 John Wiley & Sons, Ltd.
Sox2 and Pax6 maintain the proliferative and developmental potential of gliogenic neural stem cells In vitro
Authors: Gómez‐López Sandra , Wiskow Ole , Favaro Rebecca , Nicolis Silvia K. , Price David J. , Pollard Steven M. , Smith Austin
Published: July 2011

Radial‐glia‐like neural stem (NS) cells may be derived from neural tissues or via differentiation of pluripotent embryonic stem (ES) cells. However, the mechanisms controlling NS cell propagation and differentiation are not yet fully understood. Here we investigated the roles of Sox2 and Pax6, transcription factors widely expressed in central nervous system (CNS) progenitors, in mouse NS cells. Conditional deletion of either Sox2 or Pax6 in forebrain‐derived NS cells reduced their clonogenicity in a gene dosage‐dependent manner. Cells heterozygous for either gene displayed moderate proliferative defects, which may relate to human pathologies attributed to SOX2 or PAX6 deficiencies. In the complete absence of Sox2, cells exited the cell cycle with concomitant downregulation of neural progenitor markers Nestin and Blbp. This occurred despite expression of the close relative Sox3. Ablation of Pax6 also caused major proliferative defects. However, a subpopulation of cells was able to expand continuously without Pax6. These Pax6‐null cells retained progenitor markers but had altered morphology. They exhibited compromised differentiation into astrocytes and oligodendrocytes, highlighting that the role of Pax6 extends beyond neurogenic competence. Overall these findings indicate that Sox2 and Pax6 are both critical for self‐renewal of differentiation‐competent radial glia‐like NS cells. © 2011 Wiley‐Liss, Inc.
Increased excitatory amino acid transport into murine prion protein knockout astrocytes cultured in vitro
Authors: Pathmajeyan Melissa S. , Patel Sarjubhai A. , Carroll James A. , Seib Todd , Striebel James F. , Bridges Richard J. , Chesebro Bruce
Published: July 2011

Prion protein (PrP) is expressed on a wide variety of cells and plays an important role in the pathogenesis of transmissible spongiform encephalopathies. However, its normal function remains unclear. Mice that do not express PrP exhibit deficits in spatial memory and abnormalities in excitatory neurotransmission suggestive that PrP may function in the glutamatergic synapse. Here, we show that transport of D‐aspartate, a nonmetabolized L‐glutamate analog, through excitatory amino acid transporters (EAATs) was faster in astrocytes from PrP knockout (PrPKO) mice than in astrocytes from C57BL/10SnJ wild‐type (WT) mice. Experiments using EAAT subtype‐specific inhibitors demonstrated that in both WT and PrPKO astrocytes, the majority of transport was mediated by EAAT1. Furthermore, PrPKO astrocytes were more effective than WT astrocytes at alleviating L‐glutamate‐mediated excitotoxic damage in both WT and PrPKO neuronal cultures. Thus, in this in vitro model, PrPKO astrocytes exerted a functional influence on neuronal survival and may therefore influence regulation of glutamatergic neurotransmission in vivo. © 2011 Wiley‐Liss, Inc.
Longitudinal stability of subsyndromal symptoms of depression in individuals with mild cognitive impairment: relationship to conversion to dementia after 3 years
Authors: Mackin R. Scott , Insel Philip , Aisen Paul S. , Geda Yonas E. , Weiner Michael W.
Published: July 2011

Objective

To evaluate the degree to which longitudinal stability of subsyndromal symptoms of depression (SSD) is associated with conversion to dementia in patients with mild cognitive impairment (MCI).

Methods

Data from 405 MCI participants from the Alzheimer's Disease Neuroimaging Initiative (ADNI) study were analyzed. Participants were evaluated at baseline and 12‐month intervals over 3 years. Participants were designated as MCI converters if dementia was diagnosed within 3 years or as cognitively stable MCI if dementia was not diagnosed during this interval. SSD were evaluated utilizing the 15‐item Geriatric Depression Scale (GDS). Endorsement of specific SSD at baseline and the stability of SSD over 36 months were compared between the two MCI groups.

Results

Baseline symptom endorsement and stability of total GDS scores did not differentiate MCI groups. Worsening of four individual items from the GDS over time (memory problems, feelings of helplessness, loss of interest, and preference for staying at home) differentiated MCI converters from cognitively stable MCI (p < 0.05 for all). However, only increased endorsement of memory symptoms over time was associated with progression to dementia after controlling for other clinical variables (p = 0.05).

Conclusions

SSD in MCI participants largely consist of cognitive symptoms and activity limitations, and the stability of SSD over time differentiated the MCI groups better than baseline endorsement of symptoms. However, the only significant predictor of conversion to dementia was increased endorsement of memory problems, which likely represents insight into cognitive problems more than depressive symptomatology in MCI individuals. Copyright © 2011 John Wiley & Sons, Ltd.
Using spatial multiple regression to identify intrinsic connectivity networks involved in working memory performance
Authors: Gordon Evan M. , Stollstorff Melanie , Vaidya Chandan J.
Published: July 2011

Many researchers have noted that the functional architecture of the human brain is relatively invariant during task performance and the resting state. Indeed, intrinsic connectivity networks (ICNs) revealed by resting‐state functional connectivity analyses are spatially similar to regions activated during cognitive tasks. This suggests that patterns of task‐related activation in individual subjects may result from the engagement of one or more of these ICNs; however, this has not been tested. We used a novel analysis, spatial multiple regression, to test whether the patterns of activation during an N‐back working memory task could be well described by a linear combination of ICNs delineated using Independent Components Analysis at rest. We found that across subjects, the cingulo‐opercular Set Maintenance ICN, as well as right and left Frontoparietal Control ICNs, were reliably activated during working memory, while Default Mode and Visual ICNs were reliably deactivated. Further, involvement of Set Maintenance, Frontoparietal Control, and Dorsal Attention ICNs was sensitive to varying working memory load. Finally, the degree of left Frontoparietal Control network activation predicted response speed, while activation in both left Frontoparietal Control and Dorsal Attention networks predicted task accuracy. These results suggest that a close relationship between resting‐state networks and task‐evoked activation is functionally relevant for behavior, and that spatial multiple regression analysis is a suitable method for revealing that relationship. Hum Brain Mapp, 2011. © 2011 Wiley‐Liss, Inc.
Effect of Hematin Administration to Patients With Protoporphyria and Liver Disease
Authors: Bloomer Joseph R. , Pierach Claus A.
Published: July 2011

Hepatic damage in protoporphyria appears to be caused by a toxic effect of excess protoporphyrin. Therapy which reduces the formation of excess protoporphyrin may, therefore, be helpful. We examined the effects of hematin administered i.v. to two patients with protoporphyria and decompensated cirrhosis. Neither patient had side effects from the compound or manifested signs of toxicity. The vascular disappearance of hematin in one patient was similar to that in patients with porphyria who do not have structural liver disease. In both patients, biochemical changes occurred that were compatible with a reduced rate of protoporphyrin formation. Thus, hematin administration may be useful in treating patients with protoporphyria who develop liver disease.
H2–Receptor Antagonists and Hepatic Drug Disposition
Authors: Mihaly George W. , Smallwood Richard A. , Anderson Jeanette D. , Jones Brian D. , Webster Lorraine K. , Vajda Frank J.
Published: July 2011

The effect of four H2–receptor antagonists (Cimetidine, burimamide, oxmetidine, and ranitidine) on antipyrine elimination was studied in the isolated perfused rat liver. The first three drugs are substituted imidazoles, whereas ranitidine contains a furanyl nucleus. Isolated livers were perfused using a 100–ml, recycling, constant flow circuit for 4 hr. Antipyrine elimination was studied with or without an H2–receptor antagonist present. In all experiments, antipyrine concentrations declined monoexponentially. In control experiments (no other drug present), antipyrine clearance was 32.5 ± 9.0 ml per hr. This was greatly reduced in the presence of Cimetidine (clearance = 10.1 ± 0.8 and 5.8 ± 1.5 ml per hr after 1 and 5 mg doses, p < 0.001) and burimamide (4.5 ± 0.6 and 3.0 ± 1.7 ml per hr, p < 0.001). By contrast, neither oxmetidine nor ranitidine significantly altered antipyrine pharmacokinetics. These results indicate that the inhibitory effect on hepatic mixed–function oxidases is rapid in onset, independent of H2–receptor antagonist activity, and is not an inevitable consequence of the presence of an imidazole nucleus.
The psychology of infant colic: A review of current research
Authors: Kaley Fiona , Reid Vincent , Flynn Emma
Published: July 2011

Colic, or excessive infant crying, occurs during the first 3 months in approximately 15 to 20% of infants and is the most common concern for which parents seek medical advice during an infant's first year. Various physiological and environmental causes have been investigated. Some researchers have proposed multifactorial causes while others have argued that it is simply the extreme end of the normal crying continuum. As the etiology of colic is not clear, definitions of colic have relied on behavioral descriptions, and the relative merits of specific behaviors in affording an accurate definition are debated. This lack of clarity has compounded difficulties in identifying effective interventions for colic. One point of agreement is that colic is extremely distressing for parents. Some have argued that the disruption to the infant–parent relationship can have long‐term implications for development while others have argued that only if the crying persists beyond 3 months is there a risk of long‐term implications. It is concluded that due to the incidence of colic and the immediate impact it has on family functioning, more research is required to further our understanding of colic. In addition, the identification of effective coping strategies and consoling methods to assist parents through this stressful period is required.
Quantitative remineralization evolution kinetics of artificially demineralized human enamel using photothermal radiometry and modulated luminescence
Authors: Hellen Adam , Mandelis Andreas , Finer Yoav , Amaechi Bennett T.
Published: July 2011

Human molars were subjected to demineralization in acid gel followed by incubation in remineralization solutions without or with fluoride (1 or 1000 ppm). Photothermal radiometry (PTR) and modulated luminescence (LUM) frequency scans were performed prior to and during de/remineralization treatments. Transverse Micro‐Radiography (TMR) analysis followed at treatment conclusion to determine mineral loss and lesion depth. The remineralization process illustrated a complex interplay between surface and subsurface mineral deposition, confining the thermal‐wave centroid toward the dominating layer. Experimental amplitudes and phases were fitted to a coupled diffuse‐photon‐density‐wave and thermal‐wave theoretical model used to quantitatively evaluate evolving changes in thermal and optical properties of de/remineralized enamel lesions. Additional information obtained from the LUM data corroborated the remineralization kinetics affecting the PTR signals. The results pointed to enhanced effectiveness of subsurface lesion remineralization in the presence of fluoride. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thermal alteration and morphological changes of sound and demineralized primary dentin after Er:YAG laser ablation
Authors: BrandÃO Cristina Bueno , Contente Marta Maria Martins Giamatei , De Lima FabrÍCio Augusto , Galo Rodrigo , CorrÊA‐Afonso Alessandra Marques , Bachmann Luciano , Borsatto Maria Cristina
Published: July 2011

The purpose of this study was to assess the influence of Er:YAG laser pulse repetition rate on the thermal alterations occurring during laser ablation of sound and demineralized primary dentin. The morphological changes at the lased areas were examined by scanning electronic microscopy (SEM). To this end, 60 fragments of 30 sound primary molars were selected and randomly assigned to two groups (n = 30); namely A sound dentin (control) and B demineralized dentin. Each group was divided into three subgroups (n = 10) according to the employed laser frequencies: I–4 Hz; II–6 Hz, and III–10 Hz. Specimens in group B were submitted to a pH‐cycling regimen for 21 consecutive days. The irradiation was performed with a 250 mJ pulse energy in the noncontact and focused mode, in the presence of a fine water mist at 1.5 mL/min, for 15 s. The measured temperature was recorded by type K thermocouples adapted to the dentin wall relative to the pulp chamber. Three samples of each group were analyzed by SEM. The data were submitted to the nonparametric Kruskal‐Wallis test and to qualitative SEM analysis. The results revealed that the temperature increase did not promote any damage to the dental structure. Data analysis demonstrated that in group A, there was a statistically significant difference among all the subgroups and the temperature rise was directly proportional to the increase in frequency. In group B, there was no difference between subgroup I and II in terms of temperature. The superficial dentin observed by SEM displayed irregularities that augmented with rising frequency, both in sound and demineralized tissues. In conclusion, temperature rise and morphological alterations are directly related to frequency increment in both demineralized and sound dentin. Microsc. Res. Tech., 2011. © 2011 Wiley Periodicals, Inc.
RDFTools: A software tool for quantifying short‐range ordering in amorphous materials
Authors: Mitchell D.R.G. , Petersen T.C.
Published: July 2011

A software package for computing radial distribution functions and other pair correlation functions from electron diffraction patterns of disordered solids is presented. The package, called RDFTools, is freely available via the internet and allows rapid in situ measurements of such quantities as interatomic nearest neighbor distances, average bond angles and coordination numbers. The software runs under DigitalMicrograph™ (Pleasanton, California, Gatan), a very widely used program in transmission electron microscopy. All implemented algorithms have been designed to compute diffraction integrals and data‐processing averages in a fast and efficient manner to enable quick processing of publication ready, quantitative pair distribution function information. In the development of RDFTools, significant attention was paid to provide a robust and intuitive user‐interface for deriving reliable semiquantitative information. For example, RDFTools enables accurate pair separation distances to be revealed upon immediate interrogation at the microscope; even for potentially thick specimens and/or regions of unknown elemental composition. Microsc. Res. Tech., 2011. © 2011 Wiley Periodicals, Inc.
Authentication of Chinese Materia Medica decoction dregs. part II: Comparison before and after decoction of four Chinese Materia Medica that mainly comprise storage tissue
Authors: Wong Lailai , Liang Zhitao , Chen Hubiao , Zhao Zhongzhen
Published: July 2011

Authentication of Chinese Materia Medica (CMM) decoction dregs is important for ensuring the efficacy and safety of CMM when they are used in decoction. If someone got worse or poisoned after taking a decoction while the formula is appropriate, the authentication of CMM dregs is the effective method to explore the reasons. Therefore, a systematic study on the authentication of CMM dregs was carried out. In this study, two pairs of easily confused CMM dregs, Fenge (Puerariae Thomsonii Radix) and Shanyao (Dioscoreae Rhizoma), Dihuang (Rehmanniae Radix) and Huangjing (Polygonati Rhizoma), which mostly comprise storage tissues, were investigated by comparing the morphological and microscopic characteristics. Fenge and Shanyao contain abundant starch granules. After decoction their dregs were hard, nonstarchy and horn‐like. Fully gelatinized starch granules were found in the powder of Fenge dregs while incompletely gelatinized starch granules were occasionally found in the Shanyao dregs. In contrast, Dihuang and Huangjing contain water‐soluble sugars. After decoction, their dregs were hard and brittle. Their parenchymatous cells were shrunken and unknown crystals were found under microscope. Hence, the morphological and microscopic characteristics of CMM before and after decoction were different, and different changes in the CMM dregs can be illustrated by the different nature of their ergastic substance. These differences could be used to authenticate CMM dregs. Microsc. Res.Tech., 2011. © 2011 Wiley Periodicals, Inc.
Synthesis of novel piperidyl spirofused benzofurans/benzopyrans by radical cyclization
Authors: Tang Zilong , Mayrargue Joelle , Alami Mouad
Published: July 2011

Several new piperidyl spirofused benzofurans and piperidyl spirofused benzopyrans were synthesized via an intramolecular radical cyclization as the key step. It was found that the yield of the formation of five‐member ring was much higher than that of six‐member ring. In addition, the substituent attached to the benzene ring had almost no effect on the cyclization. J. Heterocyclic Chem.,(2011).
FISCAL POLICY CONSISTENCY AND ITS IMPLICATIONS FOR MACROECONOMIC AGGREGATES: THE CASE OF UGANDA
Authors: Hisali Eria , Guloba Asumani
Published: July 2011

The study employed the accounting approach to fiscal policy consistency to analyse the sustainability of Uganda's fiscal policy. The deficits were calculated from the financing side by considering increases in liabilities of the consolidated government. To assess whether the deficits have been compatible with other macroeconomic targets, the financeable deficit is derived and compared with the calculated actual deficits. The results show that the consolidated deficit is consistent with attainment of target outcomes for other macroeconomic variables, most notably inflation and gross domestic product growth rates. However, the inflation target has been achieved at the cost of an unsustainable domestic debt. Copyright © 2011 John Wiley & Sons, Ltd.
Radiosynthesis of 123I‐labelled benzimidazoles as novel single‐photon emission computed tomography tracers for the histamine H3 receptor
Authors: Champion Sue , Gross Jonathan , Robichaud Albert J , Pimlott Sally
Published: July 2011

The histamine H3 receptor is implicated in many neurological and psychological disorders and is therefore of interest as a target for pharmacological intervention. The drug development process can be facilitated by using a radiotracer for this receptor in conjunction with single‐photon emission computed tomography or positron emission tomography imaging studies, such as drug occupancy studies. This study investigates methods for the radiosynthesis of three compounds to be evaluated as novel radiotracers for the histamine H3 receptor. The radiosyntheses of the three target compounds, 123I‐WYE230949, 123I‐WYE126734 and 123I‐WYE127044 were evaluated using electrophilic iododesilylation and iododestannylation of the corresponding trimethylsilyl and tributylstannyl precursors. All three compounds could be produced in high radiochemical yield by electrophilic iododestannylation. By contrast, only two of the three (WYE230949 and WYE126734) could be produced by electrophilic iododesilylation. This is because of the fact that the trimethylsilyl precursors are less reactive than the stannyl precursors. Electrophilic iododestannylation of the tributylstannyl precursors is therefore the method of choice for radiosynthesis of these compounds because all three target compounds could be produced in high radiochemical yield.
Effects of cardiac motion on 3D contrast‐enhanced MR angiography of the carotid arteries
Authors: Jeffery Dean , Emery Derek J. , Wilman Alan H.
Published: July 2011

Purpose:

To determine the effect of cardiac‐related carotid artery motion on the image quality of 3D contrast‐enhanced MR angiography (CEMRA) in patients presenting with suspected carotid artery disease.

Materials and Methods:

Twenty patients with suspected carotid artery disease underwent cardiac‐gated cinematic steady‐state free precession of the carotid arteries followed by standard 3D CEMRA at 1.5 T. Using postprocessing, computer programs determined the degree of vessel wall dilation and translation across the cardiac cycle from the cinematic exam and related this to vessel wall sharpness in 3D CEMRA, which was determined objectively by computer analysis and subjectively by a panel of expert neuroradiologists.

Results:

In patients, across 40 arteries the average carotid vessel movement due to cardiac pulsation was 0.36 ± 0.17 mm and translation 1.53 ± 0.94 mm. When using computer analysis of sharpness, the mean carotid wall motion had a weak negative correlation with 3D CEMRA vessel sharpness (Pearson's correlation −0.23, P < 0.01). However, the same trend was not present from the radiological review.

Conclusion:

In standard 3D CEMRA in patients with suspected carotid artery disease, cardiac‐related carotid movement was a statistically significant source of degradation in vessel sharpness, but did not appear to be clinically significant. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
Interference spectroscopy with coherent anti‐Stokes Raman scattering of noisy broadband pulses
Authors: Shapiro Evgeny A. , Konorov Stanislav O. , Milner Valery
Published: July 2011

We propose a new technique for comparing two Raman active samples. The method employs optical interference of the signals generated via coherent anti‐Stokes Raman scattering (CARS) of broadband laser pulses with noisy spectra. It does not require spectrally resolved detection, and no prior knowledge about either the Raman spectrum of the samples or the spectrum of the incident light is needed. We study the proposed method theoretically and demonstrate it in a proof‐of‐principle experiment on toluene and o‐xylene samples. Copyright © 2011 John Wiley & Sons, Ltd.
SERS study of methylated and nonmethylated ribonucleosides and the effect of aggregating agents
Authors: Hobro Alison J. , Abdali Salim , Blanch Ewan W.
Published: July 2011

We present surface‐enhanced Raman scattering (SERS) spectra of the RNA nucleosides adenosine, cytidine, guanosine and uracil and the methylated derivatives 5‐methylcytidine and 7‐methylguanosine, a class of important nucleic acid components that has not previously been well characterised using SERS spectroscopy. Our work shows that the selection of aggregating agent plays a crucial role for SERS analysis of these nucleosides with K2SO4 generating immediate enhancement while NaCl only gave immediate enhancement for the pyrimidine nucleosides. The SERS spectra contain a number of marker bands that are highly sensitive to structural differences between these nucleosides, in particular methylation, and at lower concentration ranges than are possible for conventional Raman scattering. Finally, spectral analyses and assignments of the vibrational modes responsible for these marker bands are also presented, and the effect of the aggregating agent on these modes is discussed in terms of interactions between each nucleoside and the metal surface. Copyright © 2011 John Wiley & Sons, Ltd.
A hybrid substrate for surface‐enhanced Raman scattering spectroscopy: coupling metal nanoparticles to strong localised fields on a micro‐structured surface
Authors: Scholes F. H. , Davis T. J. , Vernon K. C. , Lau D. , Furman S. A. , Glenn A. M.
Published: July 2011

Electromagnetic coupling between localised plasmons on metal nanoparticles and the strong localised fields on a micro‐structured surface is demonstrated as a means to increase the enhancement factor in surface‐enhanced Raman scattering (SERS) spectroscopy. Au nanoparticles of diameter 20 nm were deposited on a micro‐structured Au surface consisting of a periodic array of square‐based pyramidal pits (Klarite). The spectra of 4‐aminothiophenol (4‐ATP) were compared before and after deposition of Au nanoparticles on the micro‐structured surface. The addition of Au nanoparticles is shown to provide significantly higher signal intensities, with improvements of the order of ∼103 per molecule compared with spectra obtained from the micro‐structured substrate alone. This hybrid approach offers promise for combining nanoparticles with micro‐ and nano‐structured surfaces in order to design SERS substrates with higher sensitivities. Copyright © 2011 John Wiley & Sons, Ltd.
Factors associated with use of wildlife underpasses and importance of long‐term monitoring
Authors: Gagnon Jeffrey W. , Dodd Norris L. , Ogren Kari S. , Schweinsburg Raymond E.
Published: July 2011

We evaluated use of 6 wildlife underpasses (UP) using video camera surveillance along State Route 260 in Arizona, USA. We documented wildlife use and compared successful UP crossings by various species and among UP. From 2002 to 2008, we recorded visits by 15,134 animals of 21 species (16 wildlife, 5 domestic) resulting in 72.4% crossing through UP. Elk (Cervus elaphus) accounted for 68% of recorded animals, white‐tailed deer (Odocoileus virginianus) and mule deer (O. hemionus) accounted for 13% and 6%, respectively. As elk and white‐tailed deer were the only species adequately represented across all UP, we used logistic regression to further evaluate factors associated with successful use of UP. To evaluate habituation over time we limited this analysis to 5 UP monitored for ≥4 yr. For elk, structural attributes and placement, season, time of day, and months monitored were associated with successful elk UP crossing in year 1, however, by year 4 only structural attributes and placement were significant, suggesting that UP structure and placement likely were of primary importance for successful elk passage. By year 4, probabilities of crossing at 4 of 5 UP converged on >0.70, indicating that given sufficient time to allow habituation, most UP we evaluated appeared to be effective for elk, regardless of structural attributes or placement. For deer, only structural attribute and placement were significant, and aside from one structure did not increase in probability of a successful crossing over time. The overall number of animals and species that crossed SR 260 via UP underscores efficacy of UP in promoting multi‐species permeability. Long‐term monitoring allows wildlife and highway managers to evaluate adaptation to wildlife crossing structures by different species. Results from this study add to our knowledge of mitigating the impact of highways on wildlife. © 2011 The Wildlife Society.
Biological and socio‐economic effects of statewide limitation of deer licenses in Colorado
Authors: Bergman Eric J. , Watkins Bruce E. , Bishop Chad J. , Lukacs Paul M. , Lloyd Mary
Published: July 2011

We evaluated the biological and socio‐economic effects of statewide limitation of mule deer (Odocoileus hemionus) hunting licenses, which began in Colorado in 1999. We implemented a before‐after‐control‐impact (BACI) analysis of annual helicopter sex and age class surveys, collected as part of the Colorado Division of Wildlife's routine monitoring, to assess changes in adult male/adult female ratios and fawn/adult female ratios in response to this change in harvest management. Following statewide limitation and reduction of license sales (1999–2006), we observed increases in adult male/adult female ratios of 7.39 (SE = 2.36) to 15.23 (SE = 1.22) adult males per 100 adult females in moderately limited areas and of 17.55 (SE = 3.27) to 21.86 (SE = 2.31) adult males per 100 adult females in highly limited areas. We simultaneously observed reductions in fawn/adult female ratios in newly limited areas by as much as 6.96 (SE = 2.19) fawns per 100 females, whereas in areas that had previously been limited we observed stabilization of fawn/adult female ratios at levels lower than levels observed under the unlimited harvest management structure. An immediate decline of $7.86 million in annual revenue stemmed from the change in harvest management, but revenue subsequently rebounded. This study provides preliminary evidence of potential effects that other state and provincial wildlife management agencies may face as they consider shifting mule deer harvest management towards limited license scenarios. © 2011 The Wildlife Society.
Reaction of a low‐molecular‐weight free radical with a flexible polymer chain: Kinetic studies on the OH + poly(N‐vinylpyrrolidone) model
Authors: Bartoszek Nina , Ulański Piotr , Rosiak Janusz M.
Published: July 2011

This work addresses the issue of kinetics of diffusion‐controlled reactions of small radicals with macromolecules in solution. Attack of pulse‐generated hydroxyl radicals on poly(N‐vinylpyrrolidone)—PVP—chains of various molecular weight in water was used as the model reaction. Pulse radiolysis with spectrophotometric detection was applied to determine the rate constants by competition kinetics. The rate constant depends both on polymer concentration and on its molecular weight. In dilute solutions, a distinct dependence of the rate constant on the molecular weight is observed. In the studied range of molecular weight, the values of reaction radius, calculated using Smoluchowski equation on the basis of experimental kinetic data, are very close to the radius of gyration of polymer coils. We believe that radius of gyration, as an easily determined parameter, could possibly serve for predicting rate constants of diffusion‐controlled reactions of polymers with low‐molecular‐weight compounds in dilute solutions. With increasing polymer concentration and thus increasing spatial overlap of polymer coils the dependence of the rate constant on the molecular weight fades away, and the rate constant values increase with increasing concentration toward the value determined for low‐molecular‐weight model of PVP. Most steep increase approximately coincides with the hydrodynamic critical concentration of a given PVP sample, reflecting the change in reaction geometry from individual coils to a continuous matrix of interpenetrating chains. © 2011 Wiley Periodicals, Inc. Int J Chem Kinet 43: 474–481, 2011