bluuebunny/crossref_metadata_2025 huggingface dataset:
Institutional settings and rent appropriation by knowledge‐based employees: the case of Major League Baseball
Authors: Chacar Aya S. , Hesterly William
Published: March 2008

We examine the role of institutional settings in determining rent appropriation by employees. Based on an inductive historical study of owner–player relations in Major League Baseball from the inception of professional baseball to the present, we show that both formal and informal institutional rules can dramatically influence rent appropriation. We draw upon anthropology research on social relations to understand how differences in informal norms regarding the social relations between the owners and the players affect appropriation. Our findings show that when social relations are defined by authority ranking, pay is determined more by fiat than by market forces or bargaining. Copyright © 2008 John Wiley & Sons, Ltd.
Sacral nerve stimulation for fecal incontinence and constipation in adults: A short version cochrane review
Authors: Mowatt G. , Glazener C. , Jarrett M.
Published: March 2008

Background

Fecal incontinence and constipation are disabling conditions that reduce quality of life. If conservative treatment fails, one option is sacral nerve stimulation (SNS), a minimally invasive technique allowing modulation of the nerves and muscles of the pelvic floor and hindgut.

Objectives

To assess the effects of SNS for fecal incontinence and constipation in adults.

Search strategy

We searched the Cochrane Incontinence Group Specialized Trials Register (searched 24 April 2007) and the reference lists of relevant articles.

Selection criteria

All randomized or quasi‐randomized trials assessing the effects of SNS for fecal incontinence or constipation in adults.

Data collection and analysis

Two review authors independently screened the search results, assessed the methodological quality of the included studies, and undertook data extraction.

Main results

Three crossover studies were included. Two, enrolling 34 (Leroi) and two participants (Vaizey), assessed the effects of SNS for fecal incontinence, and one (Kenefick), enrolling two participants, assessed SNS for constipation.In the study by Leroi, following the crossover period, participants, while still blinded, chose the period of stimulation they had preferred. Outcomes at different time points were reported separately for 19 participants who preferred the “on” and five who preferred the “off” period. For the group of 19, the median (range) episodes of fecal incontinence per week fell from 1.7 (0–9) during the “off” period to 0.7 (0–5) during the “on” period; for the group of five, however, the median (range) rose from 1.7 (0–11) during the “off” period compared with 3.7 (0–11) during the “on” period. Vaizey reported an average of six, and one, episodes of fecal incontinence per week during the “off” and “on” periods, respectively. Leroi reported that four of 27 participants experienced an adverse event resulting in removal of the stimulator; Vaizey did not report adverse events.For SNS for constipation, during the “off” crossover period the participants experienced an average of two bowel movements per week, compared with five during the “on” period. Abdominal pain and bloating occurred 79% of the time during the “off” period compared with 33% during the “on” period. No adverse events occurred.

Authors' conclusions

The very limited evidence from the included studies suggests that SNS can improve continence in selected people with fecal incontinence, and reduce symptoms in selected people with constipation. However, temporary, percutaneous stimulation for a 2–3‐week period does not always successfully identify those for whom a permanent implant will be beneficial. Larger, good quality randomized crossover trials are needed to allow the effects of SNS for these conditions to be assessed with more certainty. Neurourol. Urodynam. 27:155–161, 2008. © 2008 Wiley‐Liss, Inc.
Decreased plasma levels of metastin in early pregnancy are associated with small for gestational age neonates
Authors: Smets Eva M. L. , Deurloo Koen L. , Go Attie T. J. I. , van Vugt John M. G. , Blankenstein Marinus A. , Oudejans Cees B. M.
Published: March 2008

Objective

To investigate whether pregnancies with small for gestational age (SGA) neonates, defined as customized birth weight below the 10th centile, are associated with altered levels of metastin in maternal plasma in the first trimester.

Study Design

Maternal blood was obtained between 8 and 14 weeks of pregnancy. Levels of metastin were measured in pregnancies with (n = 31) or without SGA‐neonates (n = 31), matched for gestational age at venipuncture. Measurement of β‐hCG was included to study the influence of gestational age and placental volume on plasma levels of the measured markers.

Results

Metastin was significantly lower in SGA‐pregnancies compared to an equal number of matched uneventful pregnancies (metastin: 1376 ± 1317 pmol/L vs 2035 ± 1260 pmol/L, p = 0.035; mean ± standard deviation). β‐hCG levels were not different.

Conclusion

Metastin is significantly lower in maternal plasma in the first trimester, in pregnancies with SGA‐neonates. It might therefore be used in combination with other markers for risk estimation of growth impairment in the first trimester. Copyright © 2008 John Wiley & Sons, Ltd.
Comparative glycomics of connective tissue glycosaminoglycans
Authors: Hitchcock Alicia M. , Yates Karen E. , Costello Catherine E. , Zaia Joseph
Published: March 2008

Homeostasis of connective joint tissues depends on the maintenance of an extracellular matrix, consisting of an integrated assembly of collagens, glycoproteins, proteoglycans, and glycosaminoglycans (GAGs). Isomeric chondroitin sulfate (CS) glycoforms differing in position and degree of sulfation and uronic acid epimerization play specific and distinct functional roles during development and disease onset. This work profiles the CS epitopes expressed by different joint tissues as a function of age and osteoarthritis. GAGs were extracted from joint tissues (cartilage, tendon, ligment, muscle, and synovium) and partially depolymerized using chondroitinase enzymes. The oligosaccharide products were differentially stable isotope labeled by reductive amination using 2‐anthranilic acid‐d0 or ‐d4 and subjected to amide‐hydrophilic interaction chromatography (HILIC) online LC‐MS/MS. The analysis presented herein enables simultaneous profiling of the expression of nonreducing end, linker region, and Δ‐unsaturated interior oligosaccharide domains of the CS chains among the different joint tissues. The results provide important new information on the changes to the expression of CS GAG chains during disease and development.
Fluorene‐rich high performance polyesters: Synthesis and characterization of 9,9‐fluorenylidene and 2,7‐fluorenylene‐based polyesters with excellent optical property
Authors: Seesukphronrarak Surasak , Kawasaki Shinichi , Kobori Kana , Takata Toshikazu
Published: February 2008

Polyesters PEs containing high content of fluorene units in their backbones were synthesized from 9,9‐diarene‐substituted fluorene diols (1) and fluorene‐based diacid chlorides (2) by high temperature polycondensation at 185 °C in diphenyl ether. The molecular weights of the polyesters PE1‐PE5 were in a range of Mw 25,000–165,000. The polyesters displayed their high thermostability: the glass transition temperatures (Tg) by differential scanning calorimetry analysis ranged from 109 to 217 °C, while the 10% weight loss temperatures (Td10) measured by thermogravimetric analysis were over 400 °C in nitrogen and 395 °C in air. The polyesters had good solubility in most common organic solvents such as chloroform and toluene and gave tough, transparent and flexible cast films. The transmittance of the films was over 80% in the wavelength range from 450 to 700 nm in any PEs. The PEs exhibited high refractive index values around 1.65, while they had very low degree of birefringence. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2549–2556, 2008
An analysis technique to increase testability of object‐oriented components
Authors: Kansomkeat Supaporn , Rivepiboon Wanchai
Published: March 2008

Object‐oriented component engineering is increasingly used for system development, partly because it emphasizes portability and reusability. Each time a component is used, it must be retested in the new environment. Unfortunately, the data abstraction that components usually use results in low testability. First, internal variables cannot be directly set. Second, even though a test input may trigger a fault, the failure does not propagate to the output. This paper presents a technique to increase object‐oriented component testability, thereby making it easier to detect faults. Components are often sealed so that source code is not available. The program analysis is performed at the Java component bytecode level. A component's bytecode is analysed to create acontrol and data flow graph, which is then used to increase component testability by increasing both controllability and observability. We have implemented this technique and applied it to several components. Experimental results reveal that fault detection can be increased by using our increasing testability process. Copyright © 2008 John Wiley & Sons, Ltd.
Follow‐Up After Surgery for Benign Nodular Thyroid Disease: Evidence‐Based Approach
Authors: Phitayakorn Roy , McHenry Christopher R.
Published: March 2008

Background

There is no consensus on what constitutes appropriate methodology and timing for follow‐up of patients after surgery for benign nodular disease.

Methods

A systematic review of the medical literature using evidence‐based criteria was used to address the following four issues: (1) How often should patients who have undergone thyroidectomy for the treatment of benign nodular goiter be followed, and what constitutes appropriate follow‐up? (2) What is the most appropriate method for detecting recurrent nodular thyroid disease? (3) Does thyroid hormone administration prevent recurrent nodular thyroid disease? (4) Does iodine administration prevent recurrent nodular thyroid disease?

Results

Altogether, 742 articles were found in MEDLINE using a keyword search strategy; we then narrowed them to 23 articles. There were a total of four articles with Level I data, five articles with Level II data, one article with Level III data, and 13 articles with Level IV or retrospective data.

Conclusions

Based on the available data, it is our recommendation that patients undergoing thyroid lobectomy for benign nodular thyroid disease should be followed with an annual physical examination, neck ultrasonography, and serum thyroid‐stimulating hormone (TSH) measurement. Patients undergoing total thyroidectomy should be followed with an annual physical examination and a serum TSH measurement. Routine thyroxine and/or iodine supplementation may be useful for preventing recurrence in patients from iodine‐deficient regions.
Size-dependent Fano Interaction in the Laser-etched Silicon Nanostructures
Authors: Kumar Rajesh , Shukla AK , Mavi HS , Vankar VD
Published: March 2008

Photo-excitation and size-dependent Raman scattering studies on the silicon (Si) nanostructures (NSs) prepared by laser-induced etching are presented here. Asymmetric and red-shifted Raman line-shapes are observed due to photo-excited Fano interaction in the quantum confined nanoparticles. The Fano interaction is observed between photo-excited electronic transitions and discrete phonons in Si NSs. Photo-excited Fano studies on different Si NSs show that the Fano interaction is high for smaller size of Si NSs. Higher Fano interaction for smaller Si NSs is attributed to the enhanced interference between photo-excited electronic Raman scattering and phonon Raman scattering.
Crime and Race: A Plea for New Ideas
Authors: Gyimah-Brempong Kwabena
Published: March 2008

A review of the economics of crime literature provides an unsatisfactory explanation of the higher crime rates among African Americans compared to crime rates for whites in the US. This address challenges economists, particularly African American economists, to come up with new and credible ideas to explain the observed crime differential that could influence policies to decrease crime in the African American community.
In vitro characterization of a murine oligodendrocyte precursor cell line (BO‐1) following spontaneous immortalization
Authors: Pringproa Kidsadagon , Kumnok Jirawat , Ulrich Reiner , Baumgärtner Wolfgang , Wewetzer Konstantin
Published: March 2008

The understanding of oligodendrocyte differentiation is crucial for designing therapies of demyelinating diseases. Oligodendrocyte precursor cells are of particular interest in this context, because of their remyelinating potential. Permanent cell lines, which are a versatile tool for studying oligodendrocyte physiology, have been so far mainly established from the rat CNS. In the present study, we describe a novel murine oligodendrocyte precursor cell line (BO‐1) established by spontaneous immortalization using light microscopy, immunocytochemical phenotyping and genetic analysis. BO‐1 cells displayed a bi‐ to multipolar morphology and expressed early oligodendrocytic lineage markers, such as A2B5 and NG‐2. Expression of pre‐oligodendrocyte (O4, CNPase) and mature oligodendrocyte markers (e.g. myelin basic protein) was found in about 30% and 1.5% of the cells, respectively. Addition of serum, known to promote type‐2 astrocyte differentiation, significantly increased the number of GFAP‐positive cells, while thyroid hormones, (T3/T4) known to foster oligodendrocyte differentiation, did not substantially alter the antigenic and gene expression of myelin markers. This deficiency might be related to the high intrinsic proliferation rate of BO‐1 cells that was unaltered upon removal of mitogenic factors. Expression of O4 and CNPase in BO‐1 cells could be significantly increased by co‐culture with primary astrocytes suggesting that the differentiating potential of BO‐1 cells was influenced by environmental factors and may have to be fully explored in future studies. In summary, the novel murine BO‐1 cell line shares several characteristics with oligodendrocyte precursor cells but displays a restricted differentiation into mature oligodendrocytes.
Mechanical abrasion of kimberlite indicator minerals: experimental investigations
Authors: Afanas’ev V.P. , Nikolenko E.I. , Tychkov N.S. , Titov A.T. , Tolstov A.V. , Kornilova V.P. , Sobolev N.V.
Published: March 2008

The relative abrasive stability of kimberlite indicator minerals such as pyrope, picroilmenite, olivine, and apatite as well as diamonds and kimberlite fragments was studied experimentally, and the following sequence of mineral abrasive stability was established: pyrope–olivine–picroilmenite–apatite–kimberlite fragments. Diamond did not virtually change during the experiment. Kimberlite fragments appeared to be rather stable. Their relics were preserved until the end of the experiment, whereas the other minerals acquired wearing-resistant shapes. Pyrope, olivine, and apatite were shaped into an oval. Owing to anisotropy of microhardness, picroilmenite forms hexagonal tablets, which are typical of ancient haloes of indicator minerals in all diamondiferous regions. The parity analysis of the abrasive stabilities of pyrope and picroilmenite has shown that in the haloes of “mature” littoral zone represented by pyrope alone, with a possible admixture of diamond, picroilmenite is completely destroyed by abrasion.
Variation in longevity and traits of leaves among co-occurring understorey plants in a tropical montane forest
Authors: Shiodera Satomi , Rahajoe Joeni S. , Kohyama Takashi
Published: March 2008

The relationship between leaf longevity and other leaf traits was compared among different life-form categories (trees, herbs, climbers and epiphytes) of 101 plant species in a tropical montane forest on Mt. Halimun, West Java, Indonesia. We applied the Cox proportional hazards regression to estimate the leaf longevity of each species from 30 mo of census data. We examined whether estimated longevity was explained by either species life-form categories, taxonomic groupings (eudicots, monocots, magnoliids and chloranthales, and ferns) or such leaf traits as leaf area, leaf mass per area (LMA), mass-based leaf nitrogen, penetrometer reading, condensed-tannin-free total phenolics and condensed tannin. There was a wide-ranged interspecific variation in leaf longevity, mostly 10–50 mo, similarly across life-form categories. LMA showed a strong positive influence on leaf longevity. We found that relationships between leaf longevity and some leaf traits were different among various life forms. Trees tended to have high LMA, while climbers tended to have low LMA at the same leaf longevity. We hypothesize that such difference among life forms reflects shoot architecture characteristics. Multi-shoot trees with branching architecture need to have self-supporting leaves, whereas semi-epiphytic climbers can maintain relatively low biomass investment to leaves hanging or relying upon the mechanical support from host plants.
Patterns of community composition in two tropical tree frog assemblages: separating spatial structure and environmental effects in disturbed and undisturbed forests
Authors: Ernst Raffael , Rödel Mark-Oliver
Published: March 2008

An on-going controversy in community ecology involves the debate about the many factors that affect the assembly and composition of a given species assemblage. Theory suggests that community composition is influenced by environmental gradients or biotic processes. This study examines patterns of community composition in two tropical tree frog assemblages of primary and exploited lowland rain-forest sites in the Guiana Shield area of central Guyana, South America and the Upper Guinean rain-forest block of south-western Côte d'Ivoire, West Africa. We tested community composition and species abundance data of two adult tree frog communities collected on 21 standardized transects during a period of 5 y for evidence of spatial correlation in community composition. We applied simple and partial Mantel tests to separate the effects of environmental variables, spatial distance and spatial autocorrelation on community composition. Whenever environmental effects were accounted for, we found significant positive spatial correlation of community composition. All assemblages appeared to be spatially structured, i.e. sites in close proximity had similar species assemblages. However, spatially structured environmental variation (autocorrelation) did not account for the spatial structure of species incidence. Environmental factors did not prove to be significant predictors of species incidence in any of the assemblages analysed, even if we controlled for spatial effects. Observed correlation patterns of species composition were consistent within respective realms and disturbance regimes. Moreover, general correlation patterns were consistent between geographic regions. These results are in contrast to previously published results from a study on leaf-litter anurans and indicate that group-specific differences must not be neglected when analysing patterns of species composition in anurans as they may drastically alter the outcome of the analysis.
Movements of the bat Sturnira lilium and its role as a seed disperser of Solanaceae in the Brazilian Atlantic forest
Authors: Mello Marco Aurelio Ribeiro , Kalko Elisabeth Klara Viktoria , Silva Wesley Rodrigues
Published: March 2008

Bats and birds carry out most of the seed dispersal in the Neotropics (Galindo-Gonzáles et al. 2000), and are crucial for the dynamics and regeneration of tropical forests (Whittaker & Jones 1994). However, only a few details are known about the interactions in particular bat–fruit systems. Most frugivorous bats are highly mobile (Bernard & Fenton 2003), and do not harm seeds (Fleming & Sosa 1994), suggesting that they are legitimate and effective seed dispersers (sensu Fleming & Sosa 1994).
Rooting depth and above-ground community composition in Kalahari sand woodlands in western Zimbabwe
Authors: Holdo Ricardo M. , Timberlake Jonathan
Published: March 2008

The pattern of coarse-root distribution was analysed in the woody plant community along a 200-m edaphic gradient on a Kalahari sand woodland catena in Zimbabwe. The root systems of 45 trees and shrubs were excavated, mapped, and digitized to analyse rooting depth and architecture. Patterns of change in the above-ground community were also identified along this transect. Rooting depth increased, and the centre of mass of the root profile shifted towards the maximum rooting depth as a function of distance up the catena. The data also suggest that interspecific variation in rooting depth may increase up the catena. The below-ground pattern was accompanied by above-ground changes: species richness and basal area also increased up the catena. It is hypothesized that increasing soil depth allows greater coexistence of alternative water-use strategies, resulting in the observed increase in species richness up the catena.
Temporal and spatial variation of fine roots in a northern AustralianEucalyptus tetrodontasavanna
Authors: Janos David P. , Scott John , Bowman David M. J. S.
Published: March 2008

Six rhizotrons in anEucalyptus tetrodontasavanna revealed seasonal changes in the abundance of fine roots (≤ 5 mm diameter). Fine roots were almost completely absent from the upper 1 m of soil during the dry season, but proliferated after the onset of wet-season rains. At peak abundance of 3.9 kg m−2soil surface, fine roots were distributed relatively uniformly throughout 1 m depth, in contrast with many tropical savannas and tropical dry forests in which fine roots are most abundant near the soil surface. After 98% of cumulative annual rainfall had been received, fine roots began to disappear rapidly, such that 76 d later, less than 5.8% of peak abundance remained. The scarcity of fine roots in the upper 1 m of soil early in the dry season suggests that evergreen trees may be able to extract water from below 1 m throughout the dry season. Persistent deep roots together with abundant fine roots in the upper 1 m of soil during the wet season constitute a ‘dual’ root system. Deep roots might buffer atmospheric CO2against increase by sequestering carbon at depth in the soil.
Phase Contrast X-Ray Synchrotron Imaging: Opening Access to Fossil Inclusions in Opaque Amber
Authors: Lak Malvina , Néraudeau Didier , Nel André , Cloetens Peter , Perrichot Vincent , Tafforeau Paul
Published: March 2008

A significant portion of Mesozoic amber is fully opaque. Biological inclusions in such amber are invisible even after polishing, leading to potential bias in paleoecological and phylogenetic studies. Until now, studies using conventional X-ray microtomography focused on translucent or semi-opaque amber. In these cases, organisms of interest were visualized prior to X-ray analyses. It was recently demonstrated that propagation phase contrast X-ray synchrotron imaging techniques are powerful tools to access invisible inclusions in fully opaque amber. Here we describe an optimized synchrotron microradiographic protocol that allowed us to investigate efficiently and rapidly large amounts of opaque amber pieces from Charentes (southwestern France). Amber pieces were imaged with microradiography after immersion in water, which optimizes the visibility of inclusions. Determination is not accurate enough to allow precise phylogenetic studies, but provides preliminary data on biodiversity and ecotypes distribution; phase contrast microtomography remains necessary for precise determination. Because the organisms are generally much smaller than the amber pieces, we optimized local microtomography by using a continuous acquisition mode (sample moving during projection integration). As tomographic investigation of all inclusions is not practical, we suggest the use of a synchrotron for a microradiographic survey of opaque amber, coupled with microtomographic investigations of the most valuable organisms.
Light-Emitting Diodes Are Better Illumination Sources for Biological Microscopy than Conventional Sources
Authors: Cole Richard W. , Turner James N.
Published: March 2008

Light-emitting diodes (LEDs) can be easily and inexpensively integrated into modern light microscopes. There are numerous advantages of LEDs as illumination sources; most notably, they provide brightness and spectral control. We demonstrate that for transmitted light imaging, an LED can replace the traditional tungsten filament bulb while offering longer life; no color temperature change with intensity change; reduced emission in the infrared region, which is important for live cell imaging; and reduced cost of ownership. We show a direct substitution of the typical tungsten bulb with a commercially available LED and demonstrated the color stability by imaging a histology section over a wide range of light intensities. For fluorescent imaging, where the typical illumination sources are mercury or xenon lamps, we demonstrate that LEDs offer advantages of providing a longer lifespan, having a more constant intensity output over time, more homogeneous illumination, and significantly lower photon dose. Our LED equipped system was used to image and deconvolve dual fluorescently labeled cells, as well as image cells undergoing mitosis expressing green fluorescent protein–histone 2B complex. The timing of the stages of mitosis is well established as an indicator of cell viability.
Swiss spring plant phenology 2007: Extremes, a multi‐century perspective, and changes in temperature sensitivity
Authors: Rutishauser This , Luterbacher Jürg , Defila Claudio , Frank David , Wanner Heinz
Published: March 2008

Spring (March–May) 2007 was characterized by record high temperatures over European land areas. Anomalously high temperatures led to a very early onset of plant phenological spring phases, including 98 record early observations out of a possible total of 302 (32%) for selected phases in Switzerland. In the context of the last 300 years and based on three tree species, 2007 marks the third earliest, after 1961 and 1794, plant phenological spring onset in Switzerland. We show that the temperature sensitivity of Swiss plant phenology to spring temperatures has changed within the last three centuries: sensitivity has generally increased over the record period but also decreased during two periods with warming trends (1890–1950; 1970–2007).
A quantitative link between CO2 emissions from tropical vegetation fires and the daily tropospheric excess (DTE) of CO2 seen by NOAA‐10 (1987–1991)
Authors: Chédin A. , Scott N. A. , Armante R. , Pierangelo C. , Crevoisier C. , Fossé O. , Ciais P.
Published: March 2008

Monthly mean mid‐tropospheric CO2 columns over the tropics are retrieved from evening and morning observations of NOAA‐10 (1987–1991). We find that the difference between these two columns (“Daily Tropospheric Excess”, DTE) increases up to 3 ppm over regions affected by fires. At regional scale over Africa, America, and Australia, the variations of the DTE are very similar to those of independently derived biomass burning CO2 emissions. A strong correlation (R2 ∼ 0.8) is found between regional mean DTE and fire CO2 emissions values from the Global Fire Emissions Database (GFEDv2) even though the two products span over periods ten years apart from each other. The DTE distribution over Africa indicates that the southern hemisphere experiences 20% more fire activity during El Niño conditions than during La Niña conditions and the reverse for the northern hemisphere. Such an African dipole of ENSO‐related fire variability is comparable to changes analyzed from GFEDv2 CO2 emission maps. However, the estimated one sigma uncertainty on the DTE remains close to this DTE ENSO signal. The physical mechanism linking DTE with emissions is not fully elucidated. Hot convective fire plumes injecting CO2 into the troposphere during the afternoon peak of fire activity, seen by the satellite at 1930 LT, and then being diluted by large scale atmospheric transport, before the next satellite pass at 0730 LT, could explain the tight observed relationship between DTE and CO2 emissions. We conclude that DTE data can be very useful to quantitatively reconstruct fire emission patterns before the ATSR and MODIS era when better quality fire count and burned area data became available.
Life Sciences
Authors: Rang H P
Published: March 2008

British Journal of Pharmacology (2008) 153, S1; doi:10.1038/bjp.2008.31
The phytocannabinoid Δ9‐tetrahydrocannabivarin modulates inhibitory neurotransmission in the cerebellum
Authors: Ma Y‐L , Weston S E , Whalley B J , Stephens G J
Published: March 2008

Background and purpose:The phytocannabinoid Δ9‐tetrahydrocannabivarin (Δ9‐THCV) has been reported to exhibit a diverse pharmacology; here, we investigate functional effects of Δ9‐THCV, extracted fromCannabis sativa, using electrophysiological techniques to define its mechanism of action in the CNS.

Experimental approach:Effects of Δ9‐THCV and synthetic cannabinoid agents on inhibitory neurotransmission at interneurone‐Purkinje cell (IN‐PC) synapses were correlated with effects on spontaneous PC output using single‐cell and multi‐electrode array (MEA) electrophysiological recordings respectively, in mouse cerebellar brain slicesin vitro.

Key results:The cannabinoid receptor agonist WIN 55,212‐2 (WIN55) decreased miniature inhibitory postsynaptic current (mIPSC) frequency at IN‐PC synapses. WIN55‐induced inhibition was reversed by Δ9‐THCV, and also by the CB1receptor antagonist AM251; Δ9‐THCV or AM251 acted to increase mIPSC frequency beyond basal values. When applied alone, Δ9‐THCV, AM251 or rimonabant increased mIPSC frequency. Pre‐incubation with Δ9‐THCV blocked WIN55‐induced inhibition. In MEA recordings, WIN55 increased PC spike firing rate; Δ9‐THCV and AM251 acted in the opposite direction to decrease spike firing. The effects of Δ9‐THCV and WIN55 were attenuated by the GABAAreceptor antagonist bicuculline methiodide.

Conclusions and implications:We show for the first time that Δ9‐THCV acts as a functional CB1receptor antagonist in the CNS to modulate inhibitory neurotransmission at IN‐PC synapses and spontaneous PC output. Δ9‐THCV‐ and AM251‐induced increases in mIPSC frequency beyond basal levels were consistent with basal CB1receptor activity. WIN55‐induced increases in PC spike firing rate were consistent with synaptic disinhibition; whilst Δ9‐THCV‐ and AM251‐induced decreases in spike firing suggest a mechanism of PC inhibition.
Cardiorespiratory Fitness Predicts Changes in Adiposity in Overweight Hispanic Boys
Authors: Byrd‐Williams Courtney E. , Shaibi Gabriel Q. , Sun Ping , Lane Christianne J. , Ventura Emily E. , Davis Jaimie N. , Kelly Louise A. , Goran Michael I.
Published: February 2008

We have previously shown that cardiorespiratory fitness predicts increasing fat mass during growth in white and African‐American youth, but limited data are available examining this issue in Hispanic youth. Study participants were 160 (53% boys) overweight (BMI ≥ 85th percentile for age and gender) Hispanic children (mean ± s.d. age at baseline = 11.2 ± 1.7 years). Cardiorespiratory fitness, assessed by VO2max, was measured through a maximal effort treadmill test at baseline. Body composition through dual‐energy X‐ray absorptiometry and Tanner stage through clinical exam were measured at baseline and annually thereafter for up to 4 years. Linear mixed models were used to examine the gender‐specific relationship between VO2max and increases in adiposity (change in fat mass independent of change in lean tissue mass) over 4 years. The analysis was adjusted for changes in Tanner stage, age, and lean tissue mass. In boys, higher VO2max at baseline was inversely associated with the rate of increase in adiposity (β = −0.001, P = 0.03); this effect translates to a 15% higher VO2max at baseline resulting in a 1.38 kg lower fat mass gain over 4 years. However, VO2max was not significantly associated with changes in fat mass in girls (β = 0.0002, P = 0.31). In overweight Hispanic boys, greater cardiorespiratory fitness at baseline was protective against increasing adiposity. In girls however initial cardiorespiratory fitness was not significantly associated with longitudinal changes in adiposity. These results suggest that cardiorespiratory fitness may be an important determinant of changes in adiposity in overweight Hispanic boys but not in girls.
Endovascular Treatment of Carotid-Cavernous Fistulas: Review of 12 Cases
Authors: Siqueira S. B.P. , Lázaro B. C. , Gonçalves M. B. , Maia O. , Siqueira C. M. P. , Landeiro J. A.
Published: February 2008

Carotid-cavernous fistulas (CCFs) are an uncommon pathology in current neurosurgical practice. Furthermore, they generally present a challenge to the neurosurgeon because of both their deep location and the major neurovascular structures that surround them. CCFs consist of a vascular anomaly in which blood flows from meningeal branches of the internal and external carotid arteries, or directly from the internal carotid artery, into the venous circulation around and in the cavernous sinus. Twelve patients with direct and indirect/dural CCFs who underwent examination and treatment between July 2003 and February 2006 are reported here. All patients of this retrospective evaluation were symptomatic at the time of diagnosis, which was confirmed by cerebral angiography. The patients were treated by endovascular approaches and the CCFs were occluded. From our evaluation, we concluded that the endovascular procedure is safe, effective and minimally invasive in patients with CCF.
The Practical Application of Sustainable Tourism Development Principles: A Case Study of Creating Innovative Place-Making Tourism Strategies
Authors: Billington Robert D. , Carter Natalie , Kayamba Lilly
Published: March 2008

The Blackstone Valley is working to create a sustainable, resilient, visitor destination using whole place-making techniques. The Blackstone Valley Tourism Council applies leadership and commitment to innovative sustainable geotourism principles. The Tourism Council fulfills the vision of sustainable tourism through its Sustainable Tourism Planning and Development Laboratory (STPDL). The Laboratory's purpose is to share the Tourism Council's experience in developing planned sustainable tourism with tourism leaders and community stakeholders seeking to develop viable destinations. The STPDL presents a learning initiative that prepares decision makers and shapers to thoughtfully develop and regenerate their communities using sustainable tourism principles. In the formation of the Laboratory mission, certain sustainable tourism development issues stood out as significant and needing prompt attention by practitioners. In response, the Laboratory has developed and continues to develop a series of robust symposiums, conferences, and programmes to link the Laboratory's work to the thirst for sound tourism development knowledge.
Surface characterization of carbon nanotubes irradiated by electron beam
Authors: Lee Jeonggil , Kim Euikwon , Jeon Jaekyun , Lee Yoonman , Kim Jae-yong
Published: March 2008

Multiwalled carbon nanotubes (MWCNTs) were irradiated by high-energy electron beams with different dosing amounts, and the physical properties including morphology and local surface structure were investigated by using a gas adsorption isotherm apparatus. The layering properties of argon on MWCNTs were measured from 65to80K, and the interaction of argon on the surface was analyzed. Little change of surface structure between unirradiated and irradiated MWCNT samples was found. Interestingly, broader isotherm steps from the electron beam irradiated samples were found, although the amount of gas molecules forming the first atomic layer remains the same for the samples before and after irradiating the beams. This observation was supported by calculated values of the two-dimensional compressibility. Our combined results suggest that dosing of the electron beam on the carbon nanotubes induced the local surface defects, while no structural modification occurs.
Investigation of Ga substitution in cobalt ferrite (CoGaxFe2−xO4) using Mossbauer spectroscopy
Authors: Krieble K. , Devlin M. , Lee S. J. , Aldini S. T. , Snyder J. E.
Published: March 2008

Ga-substituted cobalt ferrite oxides show promise as high magnetostriction, high sensitivity magnetoelastic materials for sensor and actuator applications, but their atomic-level behavior is not yet well understood. In this study, the magnetic environments of the Fe atoms in Ga-substituted cobalt ferrite have been investigated using Mossbauer spectroscopy. A series of five powder samples with CoGaxFe2−xO4 compositions (x=0.0–0.8) was investigated using transmission geometry. Results show two distinct six-line hyperfine patterns, which are identified as Fe in A (tetrahedral) and B (octahedral) spinel sites. Increasing Ga concentration is seen to decrease the hyperfine field strength for both A and B sites, as well as increasing the width of those distributions, consistent with the nonmagnetic nature of Ga3+ ions. Effects are more pronounced for the B sites than the A sites. Results for Ga substitution show more pronounced effects than for previous studies with Cr3+ or Mn3+ substitution: the hyperfine fields decrease and distribution widths increase at greater rates, and the differences between A and B site behavior are more pronounced. Results indicate that at least for the lower Ga concentrations, the Ga3+ ions substitute predominantly into the A sites, in contrast to Cr3+ and Mn3+ which substitute into the B sites. This interpretation is supported by measurements of magnetization at low temperatures.
Static and dynamical properties of circular NiFe∕Cu∕Co nanodisks
Authors: Vavassori P. , Bonanni V. , Busato A. , Gubbiotti G. , Madami M. , Adeyeye A. O. , Goolaup S. , Singh N. , Spezzani C. , Sacchi M.
Published: February 2008

We present an experimental investigation of the static and dynamical properties of array of Ni80Fe20 (10nm)∕Cu (10nm)∕Co (10nm) disks with diameter of 230nm and edge-to-edge spacing of 160nm. Magnetization reversal process studied by superconducting quantum interference device magnetometry, resonant scattering of polarized soft x-ray, and three-dimensional micromagnetic simulations reveals that the interlayer magnetostatic interaction and the different coercivities of the two layers are the key factors that determine the magnetization reversal of the disks through a sequence of antiparallel states. The dynamical properties were studied by Brillouin light scattering and micromagnetic simulations which solve the discretized Landau-Lifshitz-Gilbert equation in the time domain and calculated locally the Fourier transform. The comparison between measurements and simulations allowed us to correlate the field dependence of different modes in each ferromagnetic layer to their localization inside the disk.
The AM05 density functional applied to solids
Authors: Mattsson Ann E. , Armiento Rickard , Paier Joachim , Kresse Georg , Wills John M. , Mattsson Thomas R.
Published: March 2008

We show that the AM05 functional [Armiento and Mattsson, Phys. Rev. B 72, 085108 (2005)] has the same excellent performance for solids as the hybrid density functionals tested in Paier et al. [J. Chem. Phys. 124, 154709 (2006); 125, 249901 (2006)]. This confirms the original finding that AM05 performs exceptionally well for solids and surfaces. Hartree–Fock hybrid calculations are typically an order of magnitude slower than local or semilocal density functionals such as AM05, which is of a regular semilocal generalized gradient approximation form. The performance of AM05 is on average found to be superior to selecting the best of local density approximation and PBE for each solid. By comparing data from several different electronic-structure codes, we have determined that the numerical errors in this study are equal to or smaller than the corresponding experimental uncertainties.
Study on magnetophotonic crystals for use in reflection-type magneto-optical spatial light modulators
Authors: Takahashi K. , Kawanishi F. , Mito S. , Takagi H. , Shin K. H. , Kim J. , Lim P. B. , Uchida H. , Inoue M.
Published: March 2008

A magneto-optical spatial light modulator (MOSLM) is a real-time programmable device for modulating the amplitude and/or phase of two-dimensional optical signals at a high speed. Recently, we reported the development of the transmission-type MOSLM (T-MOSLM) based on a one-dimensional magnetophotonic crystal (MPC) with a high driving performance. However, further improvement of the T-MOSLM is required. The structure of the T-MOSLM has low optical efficiency due to weakening of transmittance through electrodes; furthermore, the fabrication of the driving electrodes is a very complicated process. In this study, we suggest a new design of the MPC for a reflection-type MOSLM (R-MOSLM). The idea of a reflection-type MPC (R-MPC) is to replace one of the Bragg mirrors with an aluminum reflection film. The structure is glass∕(Ta2O5∕SiO2)k∕Bi:YIG∕Al, where k is the repetition number. The approach of the optimal structure of the R-MPC was done by the calculation of the matrix approach method. In the calculation of the newly designed R-MPC, Kerr rotation of −10° was obtained. This result implied that the performance of the R-MOSLM using the MPC could be highly improved. According to the optimization of the calculation, the R-MPC was fabricated and its Kerr rotation was −2.2°. This means that Kerr rotation was enhanced by using the new design of the reflection-type MPC. In addition, surface reflection was the reason for the low reflectance and deterioration of Kerr rotation.
Nonlinear thermocurrent beam instability of a weakly ionized plasma
Authors: Hatami M. M. , Niknam A. R. , Shokri B. , Rukhadze A. A.
Published: February 2008

The boundaries of the thermocurrent instability in the linear theory and its maximum development increment are determined. It is shown that the group velocity in this instability depends on the wave vector giving rise to the modulational instability. Then the theory of the thermocurrent instability is considered in the nonlinear regime. In the nonlinear regime, the one-dimensional theory of the thermocurrent instability shows that the instability is caused by negative diffusion in a dense quasineutral plasma under the condition of nonresonant Cerenkov radiation. In this case, plasma diffuses from the rarefied region to the dense region until density falls down so that the quasineutrality condition would be violated and thus diffusion again would become positive. In conclusion, a longitudinal periodic nonlinear structure with a specific parameter is formed in the plasma.
Relaxation and self-organization in two-dimensional plasma and neutral fluid flow systems
Authors: Das Amita
Published: March 2008

Extensive numerical studies in the framework of a simplified two-dimensional model for neutral and plasma fluid for a variety of initial configurations and for both decaying and driven cases are carried out to illustrate relaxation toward a self-organized state. The dynamical model equation constitutes a simple choice for this purpose, e.g., the vorticity equation of the Navier–Stokes dynamics for the incompressible neutral fluids and the Hasegawa–Mima equation for plasma fluid flow system. Scatter plots are employed to observe a development of functional relationship, if any, amidst the generalized vorticity and its Laplacian. It is seen that they do not satisfy a linear relationship as the well known variational approach of enstrophy minimization subject to constancy of the energy integral for the two-dimensional (2D) system suggests. The observed nonlinear functional relationship is understood by separating the contribution to the scatter plot from spatial regions with intense vorticity patches and those of the background flow region where the background vorticity is weak or absent altogether. It is shown that such a separation has close connection with the known exact analytical solutions of the system. The analytical solutions are typically obtained by assuming a finite source of vorticity for the inner core of the localized structure, which is then matched with the solution in the outer region where vorticity is chosen to be zero. The work also demonstrates that the seemingly ad hoc choice of the linear vorticity source function for the inner region is in fact consistent with the self-organization paradigm of the 2D systems.
Nonlinear dynamics of a plasma-filled diode in the presence of a magnetic field with loads
Authors: Li Daohui , Zhang Jianxin , Chen Xiaodong
Published: February 2008

A plasma-filled diode can be taken as a simplified model for the interaction space of some microwave oscillators, such as, virtual cathode oscillators. A magnetic field has played an important role in showing the nonlinear dynamics of the diode in a previous study. In the presence of a magnetic field, the diode is connected to various types of loads consisting of capacitance, inductance, and resistance in series. The nonlinear dynamics and chaos have been investigated by using both analytical analysis and particle-in-cell simulation. It has been shown that the diode can operate in different dynamical regimes: steady, oscillatory, chaotic, and unstable.
A hot probe setup for the measurement of Seebeck coefficient of thin wires and thin films using integral method
Authors: Sarath Kumar S. R. , Kasiviswanathan S.
Published: February 2008

An experimental setup is developed for the measurement of the Seebeck coefficient of thin wires and thin films in the temperature range of 300–650K. The setup makes use of the integral method for measuring the Seebeck voltage across the sample. Two pointed copper rods with in-built thermocouples serve as hot and cold probes as well as leads for measuring the Seebeck voltage. The setup employs localized heating and enables easy sample loading using a spring loaded mounting system and is fully automated. Test measurements are made on a constantan wire and indium tin oxide (ITO) thin film for illustration. The Seebeck voltage obtained for constantan wire is in agreement with the NIST data for copper constantan couple with an error of 1%. The calculated carrier concentration of ITO film from the Seebeck coefficient measurement is comparable with that obtained by electrical transport measurements. The error in the Seebeck coefficient is estimated to be within 3%.
Viscous gravity currents inside confining channels and fractures
Authors: Takagi Daisuke , Huppert Herbert E.
Published: March 2008

Unidirectional flows of long, thin, Newtonian, viscous gravity currents inside either horizontal or inclined channels are studied theoretically and experimentally. Effects due to temporal variations in the input rate at a point source and spatial variations in the channel shape are considered, with surface tension effects neglected. The current evolves with a self-similar structure at large times when the total volume of fluid scales with time t like tα and the spreading in the lateral direction y is constrained by a rigid boundary of height a∣y∕a∣n, where the length scale of the channel size a varies with distance x along the flow like xb and α≥0, b≥0 and n>0 are prescribed constants. The extent of the flow scales like tc, where the constant c depends linearly on α and is determined in terms of α, b, and n. Amongst channels that remain uniform along the flow (b=0), a V-shaped channel (n=1) gives rise to either a fastest or slowest propagation rate of the current depending on whether α<αc or α>αc, respectively, while the value of c is the same for all n when α=αc, with either αc=1∕2 or αc=1 for horizontal or inclined flows, respectively. The position of a current inside either an extremely narrow or nearly flat V-shaped channel that gently widens along the flow is also studied and shown to be proportional to a power of time. We determine that the spreading is constrained mainly by volume conservation for the case n>1 inside wide channels and by frictional drag at the rigid boundaries for n<1 inside narrow fractures.