bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the generation of high-energy photons detected by the Fermi Satellite from gamma-ray bursts
Authors: Kumar P. , Duran R. Barniol 
Published: October 2009

Abstract
Observations of gamma-ray bursts by the Fermi satellite, capable of detecting photons in a very broad energy band: 8keV to &gt;300GeV, have opened a new window for the study of these enigmatic explosions. It is widely assumed that photons of energy larger than 100 MeV are produced by the same source that generated lower energy photons – at least whenever the shape of the spectrum is a Band function. We report here a surprising result – the Fermi data for a bright burst, GRB 080916C, unambiguously shows that the high-energy photons (≳102MeV) were generated in the external shock via the synchrotron process, and the lower energy photons had a distinctly different source. The magnetic field in the region where high-energy photons were produced (and also the late-time afterglow emission region) is found to be consistent with shock compressed magnetic field of the circum-stellar medium. This result sheds light on the important question of the origin of magnetic fields required for gamma-ray burst afterglows. The external shock model for high-energy radiation makes a firm prediction that can be tested with existing and future observations.
The relation between Δv and vmax for solar-like oscillations
Authors: Stello D. , Chaplin W. J. , Basu S. , Elsworth Y. , Bedding T. R. 
Published: October 2009

Abstract
Establishing relations between global stellar parameters and asteroseismic quantities can help improve our understanding of stellar astrophysics and facilitate the interpretation of observations. We present an observed relation between the large frequency separation, Δν, and the frequency of maximum power, νmax. We find that Δν∝ν0.77max, allowing prediction of Δν to about 15 per cent given νmax. Our result is further supported by established scaling relations for Δν and νmax and by extended stellar model calculations, which confirm that Δν can be estimated using this relation for basically any star showing solar-like oscillations in the investigated range (0.5 &lt; M/M ⊙ &lt; 4.0).
In vitro evaluation of effect of various endodontic solutions on selected physical properties of white mineral trioxide aggregate
Authors: Aggarwal Vivek , Jain Anurag , Kabi Debipada 
Published: October 2009

AbstractDuring endodontic therapy various irrigating solutions at different concentrations and duration are used. These chemical solutions may affect the setting reaction of mineral trioxide aggregate (MTA). The aim of this study was to evaluate the effect of sodium hypochlorite (NaOCl) (5.25%), chlorhexidine gluconate (CHX) (2%), ethylenediaminetetraacetic acid (EDTA) solution (17%) and BioPure MTAD on surface micro‐hardness and flexural strength of white MTA. Twenty‐five disk‐shaped and 25 bar‐shaped specimens were divided into five groups and were stored under distilled water, NaOCl (5.25%), chlorhexidine CHX (2%), EDTA solution (17%) and BioPure MTAD for 7 days. The micro‐hardness of disk specimens was measured while the flexural strength was tested on bar specimens. EDTA and BioPure MTAD significantly reduced the hardness and flexural strength as compared with other groups. Under distilled water strength remained high; therefore, a final flush with distilled water before placement of MTA is advocated, especially if decalcifying agents are used during the clinical procedure.
DNA barcoding should accompany taxonomy – the case of Cerebratulus spp (Nemertea)
Authors: SUNDBERG P. , THUROCZY VODOTI E. , STRAND M. 
Published: October 2009

AbstractMany issues in DNA barcoding need to be solved before it can reach its goal to become a general database for species identification. While species delimitations are more or less well established in several taxa, there are still many groups where this is not the case. Without the proper taxonomic background/knowledge and corroboration with other kinds of data, the DNA barcoding approach may fail to identify species accurately. The classification and taxonomy of phylum Nemertea (nemerteans, ribbon worms) are traditionally based on morphology, but are not corroborated by an increasing amount of genetic data when it comes to classification either into species or into higher taxa. The taxonomy of the phylum needs to be improved before the full potential of DNA barcoding can be utilized to make sure that valid Linnean names accompany the barcode sequences. We illustrate the problematic situation in the phylum Nemertea by a case study from the genus Cerebratulus.
Descending doses of intravitreal bevacizumab for the regression of diabetic neovascularization
Authors: Stergiou Panos K. , Symeonidis Chrysanthos , Dimitrakos Stavros A. 
Published: October 2009

Abstract.Purpose:  To report short‐term regression of neovascularization after varying intravitreal doses of bevacizumab (Avastin®; Genentech, San Francisco, California, USA) in patients with proliferative diabetic retinopathy (PDR).Methods:  Eighty eyes from 76 patients with active neovascularization of the disc (NVD) or elsewhere (NVE) caused by PDR were divided into four groups and treated with a single intravitreal bevacizumab (IVB) injection of 1.25 mg, 600 μg, 300 μg or 150 μg, respectively. All patients underwent ophthalmoscopic examination and fluorescein angiography at baseline, 1 week, 1 month and 2 months later.Results:  No significant ocular or systemic adverse events were observed. In all patients with NVD or NVE, complete resolution of leakage was recorded within the first week or the first month of the injection. Even with the lowest dose (150 μg), regression of neovascularization appeared as early as the first week and lasted for over a month. Recurrence of fluorescein leakage was observed in all groups after the first month and did not correlate with the extent of neovascularization or IVB dose.Conclusion:  Short‐term results suggest that IVB given below the standard dosage (150–300 μg compared to 1.25 mg) can lead to the achievement of complete regression of diabetic retinal neovascularization within 30–45 days of injection.
Asymmetry of diurnal intraocular pressure fluctuation between right and left eyes
Authors: Kim Mo Sae , Kim Joon Mo , Park Ki Ho , Choi Chul Young 
Published: October 2009

Abstract.Purpose:  To evaluate diurnal curves of intraocular pressure (IOP) in the right and left eyes of non‐glaucomatous patients.Methods:  We measured IOP during waking hours and in habitual positions in 102 non‐glaucomatous patients every 2 hr between 09.00 hr and 23.00 hr using a Goldman applanation tonometer. Individual factors and biometries were measured and associated with diurnal IOP variations.Results:  There was no significant difference in IOP variation between the right and left eyes over eight time‐points (repeated measure anova, P = 0.995). The mean coefficient of IOP in the right and left eyes at the eight time‐points ranged from 0.806 to 0.887. Forty‐one (40.2%), 15 (14.7%) and five (4.9%) patients showed at least one asymmetrical IOP variation over seven time intervals at the cut‐off value ≥ 2, ≥ 3 and > 3 mmHg, respectively. Mean incidence of asymmetrical IOP variation was 10.9 ± 1.6% at ≥ 2 mmHg, 2.9 ± 0.8% at ≥ 3 mmHg and 0.8 ± 0.4% at > 3 mmHg. Age, differences in anterior chamber depth, lens thickness and axial length showed several significant associations with the incidence of asymmetrical IOP variation.Conclusion:  Diurnal variation of IOP showed asymmetry between right and left eyes in patients without glaucoma. Ageing and differences in local ocular factors between bilateral eyes may affect the incidence of asymmetrical IOP variation.
Non‐contact in vivo confocal scanning laser microscopy in exfoliation syndrome, exfoliation syndrome suspect and normal eyes
Authors: Sbeity Zaher , Palmiero Pat‐Michael , Tello Celso , Liebmann Jeffrey M. , Ritch Robert 
Published: October 2009

Abstract.Purpose:  This study aimed to evaluate the efficacy of non‐contact confocal laser microscopy in detecting structural alterations of the cornea, iris and lens in fellow eyes of patients with clinically unilateral exfoliation syndrome (XFS) and XFS suspects.Methods:  In a prospective observational case series, eyes of 12 patients with clinically unilateral XFS, six XFS suspects and six age‐matched controls were divided into four groups. Group A included eyes with clinically visible exfoliation material (XFM) on the pupillary border or anterior lens capsule (n = 12); group B included fellow eyes of clinically unilateral XFS patients without visible XFM (n = 12); group C comprised eyes in XFS suspects with signs of pigment dispersion without visible XFM (n = 10), and group D consisted of control eyes with no evidence of XFM or pigment dispersion (n = 12). The cornea, iris and lens were imaged using a non‐contact lens prototype for the Rostock Cornea Module (HRT II). Images were analysed by two observers masked to the clinical findings.Results:  Visible XFM (group A) on the lens capsule was characterized by hyperreflectivity in the granular and central disc areas and hyporeflective spaces in the intermediate zones. Similar hyperreflectivity was noted in four of 12 and one of 10 eyes in groups B and C, respectively, but in none in group D. Corneal endothelial hyperreflective deposits were found in eight of 12, four of 12 and one of 10 eyes in groups A, B and C, respectively, and no eyes in group D.Conclusions:  This technology permits visualization of XFM and/or XFM‐related changes in the cornea and lens in the unaffected eyes of patients with clinically unilateral XFS. It may allow early detection of XFS and impact glaucoma screening and clinical surveillance decisions.
Prediction of transfusion requirements in surgical patients: a review
Authors: INGHILLERI GIOVANNI 
Published: October 2009

SUMMARYPreoperative estimation of transfusion requirements in patients scheduled for surgery is critical to optimize blood management, including costs, and to appropriately select patients who can benefit from alternatives to allogeneic blood transfusion. Three groups of methods for transfusion requirement prediction have been developed. The simplest methods are those that identify patients at risk of requiring transfusion support on the basis of the surgical procedure they are scheduled for and one or two clinical parameters. Preoperative hemoglobin concentration (or red blood cell mass) and age are the most reliable parameters that have emerged from the studies. A second group of methods includes approaches based on the calculation of a risk score obtained by totaling predefined values assigned to the presence or absence of a number of predictors proven to be relevant in affecting transfusion requirements in a given surgical setting. The third group is based on mathematical approaches that define transfusion requirements by comparing the two elements that determine them: the reduction in red blood cell mass induced by surgery (blood loss) and the maximum red blood cell mass that a patient, according to their clinical condition, can tolerate to lose. Experiences reported to date show these methods can all be helpful in clinical practice for predicting transfusion requirements in the individual patient. Selection of the strategy to be used depends on the precision required, the intended use and hospital organization.
Stark units and the main conjectures for totally real fields
Authors: Büyükboduk Kâzım 
Published: October 2009

AbstractThe main theorem of the author’s thesis suggests that it should be possible to lift the Kolyvagin systems of Stark units, constructed by the author in an earlier paper, to a Kolyvagin system over the cyclotomic Iwasawa algebra. In this paper, we verify that this is indeed the case. This construction of Kolyvagin systems over the cyclotomic Iwasawa algebra from Stark units provides the first example towards a more systematic study of Kolyvagin system theory over an Iwasawa algebra when the core Selmer rank (in the sense of Mazur and Rubin) is greater than one. As a result of this construction, we reduce the main conjectures of Iwasawa theory for totally real fields to a statement in the context of local Iwasawa theory, assuming the truth of the Rubin–Stark conjecture and Leopoldt’s conjecture. This statement in the local Iwasawa theory context turns out to be interesting in its own right, as it suggests a relation between the solutions to p-adic and complex Stark conjectures.
Relative importance of pacing strategy and mean power output in 1500-m self-paced cycling
Authors: Hettinga F J , de Koning J J , Hulleman M , Foster C 
Published: October 2009

IntroductionBoth mean power output (MPO) and the distribution of the available energy over the race, that is, pacing strategy, are critical factors in performance. The purpose of this study was to determine the relative importance of both pacing strategy and MPO to performance.MethodsSix well-trained, regionally competitive cyclists performed four 1500-m ergometer time trials (∼2 min). For each subject, the fastest (Fast) and slowest (Slow) time trials were compared and the relative importance of differences in power output and pacing strategy were determined with an energy flow model.ResultsThe difference in final time between Fast and Slow was 4.0 (2.5) s. Fast was performed with a higher MPO (437.8 (32.3) W vs 411.3 (39.0) W), a higher aerobic peak power (295.3 (36.8) vs 287.5 (34.7) W) and a higher anaerobic peak power (828.8 (145.4) W vs 649.5 (112.2) W) combined with a relatively higher, but not statistically different anaerobic rate constant (0.051 (0.016) vs 0.041 (0.009) W). The changes in MPO (63% anaerobic, 37% aerobic) largely explained the differences in final times. Athletes chose a different pacing strategy that was close to optimal for their physiological condition in both Fast and Slow.ConclusionDifferences in intraindividual performance were mainly caused by differences in MPO. Athletes seemed to be able to effectively adjust their pacing profile based on their “status of the day”.Keywordsmodelling performance, energy expenditure, aerobic, anaerobic, sports.
Does a population-based multifactorial lifestyle intervention increase social inequality in physical activity? The Inter99 study
Authors: Aadahl M , von Huth Smith L , Toft U , Pisinger C , Jørgensen T 
Published: October 2009

AimTo examine the effect of a multifactorial lifestyle intervention on 5-year change in physical activity (PA) and to explore whether length of education had an impact on the effect of the intervention.MethodsTwo random samples (high intervention group A, n=11 708; low intervention group B, n=1308) were invited for a health examination, assessment of absolute risk of ischemic heart disease and individual lifestyle counselling. The participation rate was 52.5%. High-risk individuals in group A were also offered group-based counselling on diet and PA and/or smoking cessation. High-risk individuals in group B were referred to usual care. All high-risk individuals were reinvited for examination and counselling after 1 and 3 years, and all participants were reexamined after 5 years. The control group (group C, n=5264, response rate 61.1%) answered a mailed questionnaire. Change in self-reported PA from baseline to 5-year follow-up was the main outcome. Level of education was classified as no vocational training, ≤4 years and >4 years. Data were analysed using longitudinal linear regression models with random intercepts.ResultsIn men, the high-intensity intervention had a beneficial effect on PA level after 5 years. The age- or time-related decrease in PA was approximately 30 min/week less compared to men in the control group (p<0.0001). Level of education had no significant impact on the effect of the intervention neither in men (p=0.39) nor in women (p=0.32).ConclusionA population-based multifactorial lifestyle intervention did not influence social inequality in PA.KeywordsLifestyle, Exercise, Randomised Intervention Study, Ischemic Heart Disease, Socioeconomic Position.
Recent tobacco tax rate adjustment and its potential impact on tobacco control in China: Table 1
Authors: Hu Teh-wei , Mao Zhengzhong , Shi Jian 
Published: October 2009

ObjectivesTo compare the new tobacco tax structure effective from May 2009 with the tax structure before May 2009 and to analyse its potential impact.MethodsPublished government statistics and estimated price elasticities of the demand for cigarettes are used to estimate the impact of the new tax rate adjustment on cigarette consumption and population health.ResultsThe new adjustment increased the tax rate by 11.7% points at the producer price level. Converting this 11.7% point increase to the retail price level would mean an increase of 3.4% points in the retail price tax rate. Thus, China's new cigarette tax rate at the retail level would be 43.4% instead of the previous 40%.ConclusionsThe primary motivation for the recent Chinese government tobacco tax adjustment is to raise additional government revenue. Because the additional ad valorem tax has not yet been transferred to smokers, there is no public health benefit. It is hoped that the Chinese government will pass along these taxes to the retail price level, which would result in between 640 000 and two million smokers quitting smoking and between 210 000 and 700 000 quitters avoiding smoking-related premature death.
The analog of Koopmans’ theorem for virtual Kohn–Sham orbital energies
Authors: Gritsenko Oleg , Baerends Evert Jan 
Published: October 2009

An analog of Koopmans’ theorem is formulated for the energies, εa, of virtual Kohn–Sham (KS) molecular orbitals (MOs) from the requirement that the KS theory provides, in principle, not only the exact electron density, but also its exact response. The starting point is the Kohn–Sham analog of Koopmans’ theorem, relating the vertical ionization energies, Ii, to the energies, εi, of the occupied MOs ( Chong, D.P.; Gritsenko, O.V.; Baerends, E.J. J. Chem. Phys. 2002, 116, 1760 ). Combining this with the coupled-perturbed equations of time-dependent density functional theory (TDDFT), exact relations between the energies, εa, of virtual KS MOs and the excitation energies, ωia, and vertical ionization energies (VIPs), Ii, are obtained. In the small matrix approximation for the coupling matrix K of TDDFT, two limiting cases of these relations are considered. In the limit of a negligible matrix element, Kia,ia, the energy, εa, can be interpreted as (minus) the energy of ionization from the ?i → ?a excited state, εa ≈ –Ia, where –Ia is defined from the relation Ii = ωia + Ia. This relation breaks down in special cases, such as charge-transfer transitions and the HOMO–LUMO (highest occupied molecular orbital – lowest unoccupied molecular orbital) transition of a dissociating electron-pair bond (also of charge-transfer character). The present results highlight the important difference between virtual orbital energies in the Kohn–Sham model (εa ≈ –Ia) and in the Hartree–Fock model (εa ≈ –Aa). Kohn–Sham differences εa – εi approximate the excitation energy, ωia, while Hartree–Fock differences [Formula: see text] do not approximate excitation energies but approximate the difference of an ionization energy and an electron affinity, Ii – Aa.
Catalyzed β scission of a carbenium ion III — Scission observed in ab initio molecular dynamics simulations
Authors: Berner Greg M. , East Allan L. L. 
Published: October 2009

The β scission (cracking) of branched carbenium ions have been observed in molecular dynamics simulations, possibly for the first time. Simulations were performed with molecular dynamics based on PW91 density functional theory, and which included three-dimensional periodic boundary replication of the unit cell to mimic long-range bulk effects. A rising-temperature algorithm was used to encourage reaction within the narrow time windows (∼10 ps) of the simulations. Twenty-eight simulations were performed, featuring alkyl ions in three different catalytic systems: the ionic liquid, [(C5H5NH+)5(Al2Cl7−)6]−, the chabazite zeolite, [AlSi23O48]−, and the chabazite zeolite, [Al4Si20O45(OH)3]−. Twenty-four runs began with unbranched sec-n-alkyl ions, but only one exhibited β scission, and only after branching to a tertiary ion and under extreme heating. In contrast, the four simulations that began with branched alkyl ions were all successful in demonstrating β scission at lower temperatures: 2,4,4-trimethyl-2-pentyl ion and 2,4-dimethyl-2-hexyl ion in each of the first two catalysts. The lifetimes of desorbed alkyl ions in the chabazite models were < 5 ps at 1000–1500 K. The β scission results support the classical Weitkamp et al. ( Appl. Catal. 1983, 8, 123 ) mechanism over the nonclassical Sie ( Ind. Eng. Chem. Res. 1992, 31, 1881 ) and the chemisorping Kazansky et al. ( J. Catal. 1989, 119, 108 ) mechanisms.
Does a fungal species drive ectomycorrhizal root traits in Alnus spp.?
Authors: Ostonen Ivika , Tedersoo Leho , Suvi Triin , Lõhmus Krista 
Published: October 2009

Ectomycorrhizal (EcM) fungi contribute significantly to the shaping of short-root morphology, playing an important role in balancing the costs and benefits of root growth and nutrient uptake and exchange in boreal forests. We aimed to assess the effect of various EcM fungal taxa on root traits at seven sites dominated by grey alder, Alnus incana (L.) Moench, and black alder, Alnus glutinosa (L.) Gaertn. Mean root size, specific root length, specific root area, root tissue density, and root-tip frequency of EcM short roots were measured in EcM anatomotypes in relation to the effects of host species, soil moisture level, and nutrient status. Redundancy analysis revealed that anatomotype, alder species, site, and soil parameters (N, P, K, Ca, and Mg concentrations, pH, organic-matter content) accounted for 42.3% (p < 0.001) of the total variation in EcM root morphology. Variation decreased in the following order: anatomotypes (27.9%) > soil parameters and sites (19.9%) > alder species (5.1%). EcM fungus species had the primary influence on EcM short-root size. EcM roots of the dominant anatomotype, Alnicola spp., had the highest specific root length and specific root area in both alder species. Short-root morphology depends most strongly on the fungal taxa involved, which indicates that the type of mycobiont has an important influence on the functional properties of fine roots.
Canopy and emergent white spruce in “pure” broadleaf stands: frequency, predictive models, and ecological importance
Authors: Cumming Steve , Trindade Mariana , Greene David , Macdonald S. Ellen 
Published: October 2009

In mixedwood boreal forests of western Canada, stands classified as “pure deciduous” by forest inventories sometimes contain a few large white spruce (Picea glauca (Moench) Voss) trees among or emerging from the canopy. These trees are important as regeneration seed sources and for habitat structure. Neither their abundance nor the characteristics of stands in which they occur have previously been quantified. Of 275 “pure aspen” stands in northeastern Alberta, 19.6% contained at least one such spruce detectable in an aerial photograph. These trees were found in stands across the range of sampled canopy heights, densities, age classes, and stand sizes and were often present in the interior of stands, not just on the perimeter. The frequency of 3 ha cells containing at least one spruce was related to (i) stand shape and size, (ii) amount of mature white spruce in adjacent forest, (iii) canopy height, (iv) stand age, and (v) stand density. We conclude that such trees are relatively abundant and widely distributed within the boreal mixedwood forests of Alberta. There is presently no provision to maintain this landscape element within managed forests. More information is needed to determine if or how they should be considered in forest management planning.