bluuebunny/crossref_metadata_2025_split huggingface dataset:
Surface reconstructions of II‐VI compound semiconductor surfaces
Authors: Kumpf Christian , Weigand Wolfgang , Müller Arthur , Wagner Joachim , Wagner Veit , Bach Peter , Schmidt Georg , Molenkamp Laurens W. , Geurts Jean , Umbach Eberhard 
Published: July 2007

AbstractThe surface structures of two model systems in the field of II‐VI semiconductors – the ZnSe(001)‐c(2×2) and the BeTe(001)‐2×1 surface – are derived from spot‐profile analysis low‐energy electron diffraction and surface X‐ray diffraction (SXRD). For the first, a Zn‐vacancy model could be unambiguously confirmed by the comparison of our SXRD data with density functional theory calculations. The BeTe surface consists of [1$ \bar 1 $0]‐oriented Te dimers inducing a large amount of surface strain. This causes pronounced vertical and lateral atomic displacements in the underlying BeTe bilayers which effectively relieve the surface strain. The experimentally derived atomic geometry is in very good agreement with the results of density functional theory calculations. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Single‐Walled Carbon‐Nanotube Spectroscopic and Electronic Field‐Effect Transistor Measurements: A Combined Approach
Authors: Kauffman Douglas R. , Star Alexander 
Published: July 2007

AbstractSpectroscopic and electronic field‐effect transistor measurements reveal complimentary information about molecular interactions with single‐walled carbon nanotubes (SWNTs). Here we demonstrate how these two complimentary techniques can be combined to further understand electronic modifications of the SWNTs. The complimentary nature of these techniques stems from the perturbation of the electronic structure of SWNTs upon electronic interaction with an electron‐donating, or ‐accepting species.
Physicochemical Characterization and Application of Yam (Dioscorea cayenensis‐rotundata) Starch as a Pharmaceutical Excipient
Authors: Zuluaga María‐Fernanda , Baena Yolima , Mora Claudia‐Elizabeth , D'León Luisa‐Fernanda Ponce 
Published: July 2007

AbstractYam starch from Dioscorea cayenensis‐rotundata complex was isolated and characterized by scanning electron microscopy (SEM), particle size analysis, X‐ray diffraction, differential scanning calorimetry (DSC), compaction and rheology, and compared to maize (Zea mays) and potato (Solanum tuberosum) starches. Yam starch exhibited a log‐normal distribution of flattened ovoid shaped granules with a mean particle size of 25 µm. X‐ray diffraction showed a C‐type crystalline pattern with the degree of relative crystallinity estimated to be 34%. DSC analysis suggests that the crystalline regions in yam starch are thermally and structurally more stable as in maize and potato. Irrespective of the relative humidity (39, 67, 78% R.H.) yam starch exhibited higher moisture uptakes than maize starch and lower than potato. Intermediate values of swelling power and amylose leaching were obtained for yam as compared to maize and potato. Compaction properties of yam and potato starches were similar. However, compacts from yam presented a relatively lower tensile strength. Aqueous starch systems (4%) of yam and maize starches showed analogous shear‐thinning (pseudo‐plastic) behavior suitably described by the power‐law model. These results support the potential use of yam starch as excipient comparable to potato starch in pharmaceutical solid forms and as thickening agent similar to maize in pharmaceutical applications.
Resistive switching effect in metal/insulator/metal heterostructures and its application for non‐volatile memory
Authors: Akinaga H. , Shima H. , Takano F. , Inoue I. H. , Takagi H. 
Published: July 2007

AbstractThis paper presents two types of resistive switching effects observed in metal/insulator/metal heterostructures: one is the forced‐switch type, and the other is the memory‐switch type. The former was observed in metal/semi‐insulating GaAs hybrid structures. The nonlinear resistive switch showed a strong magnetic field dependence at room temperature. The latter, described in this report, appears in the Pt/Co oxide/Pt capacitor structures. The resistive switch showed bistability, which is certainly a phenomenon with great promise of application to nonvolatile solid state electronic memory. For both cases, the recent experimental evidences show that the electronic state of the interface between the metal electrode and the insulator plays a crucial role in the resistive switching effect. © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
PLZT films prepared by aerosol deposition and their birefringence evaluation
Authors: Yamaguchi Takashi , Shin Kwang‐Ho , Lim Pang‐Boey , Uchida Hironaga , Inoue Mitsuteru 
Published: July 2007

AbstractPb0.91La0.09(Zr0.65Ti0.35)O3 (PLZT) films were prepared by the aerosol deposition method (ADM) and their optical and electro‐optic (EO) properties investigated for application to hologram optical switch. We found that a higher transmittance of the films was obtained with smaller particles. The transmittance of the PLZT film deposited with particles of 0.2 µm average diameter, the smallest size in this experiment, was nearly 100%, showing that the PLZT film deposited by aerosol deposition can be applied to practical optical devices. We evaluated the birefringence shift of the film to make the EO performance clear. © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Toxic cyanobacterial blooms in reservoirs under a semiarid mediterranean climate: The magnification of a problem
Authors: Naselli‐Flores Luigi , Barone Rossella , Chorus Ingrid , Kurmayer Rainer 
Published: July 2007

AbstractSicilian reservoirs constitute the most important water resources available on the island. During summer 2001, the intense water utilization of Lake Arancio reservoir reduced the water level significantly, which coincided with the formation of intense blooms formed by the microcystin (MC)‐producing cyanobacterium Microcystis aeruginosa. During summer 2003, Lake Arancio was continuously filled and the vertical stratification of the water column was maintained resulting in five to sixfold lower cell numbers of M. aeruginosa. For both years, a significant relationship between MC net production and Microcysytis cell growth was observed, implying that Microcystis cell numbers can be used to infer MC concentrations in water. Unexpectedly, dense blooms of the MC‐producing cyanobacterium Planktothrix rubescens occurred during winter 2005/2006 in the reservoirs Lake Pozzillo, Prizzi, Nicoletti, and Garcia but have not been reported earlier. In this season, MC concentrations higher than those recorded in summer were measured, implying that monitoring of Mediterranean drinking water reservoirs needs to be intensified during winter, a season usually considered to be less prone to the formation of cyanobacterial blooms. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 399–404, 2007.
Effects of perchlorate on sodium‐iodide symporter and pendrin gene expression in deer mice
Authors: Cheng Qiuqiong , Smith Ernest E. , Liu Fujun , Gentle Angela , Hooper Michael J. , Anderson Todd A. 
Published: July 2007

AbstractEffects of perchlorate on sodium‐iodide symporter (NIS) and pendrin gene expression in deer mice kidney and stomach were investigated. This was accomplished by isolating a partial cDNA sequence of deer miceNISgene of 425 bps, and quantitatively analyzingNISmRNA expression in various deer mouse tissues. The highestNISexpression level was in the stomach, followed by testes, brain, and large intestine; very low expression ofNISwas observed in the lung, kidney, heart, and liver. Exposure to perchlorate through drinking water for 28 days did not significantly increaseNISgene expression in the kidney and stomach, and pendrin gene expression in the kidney. In a depuration experiment in which deer mice were exposed to perchlorate for 8‐h followed by an 88‐h depuration period, no significant difference was observed between the low and high exposure groups in terms ofNISor pendrin gene expression in the kidney or stomach at the end of the experiment. Furthermore, no significant linear relationship was observed between gene expression (eitherNISor pendrin) in the kidney and perchlorate mass excreted via urine at day 28, average daily excretion, or total excretion mass over the 28 day exposure. Several factors could influence the effect of perchlorate exposure on NIS and pendrin gene expression in the stomach and kidney, including (1) pre‐exposure to trace perchlorate through food and water perhaps resulting in adaptation (or tolerance) in these animals; (2) metabolism of perchlorate in deer mice causing only 46–61% perchlorate excreted into urine. It is also possible that there is no effect of perchlorate exposure and/or urinary excretion on NIS and pendrin gene expression, particularly in the kidney. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 390–398, 2007.
The alteration of Microcystis aeruginosa biomass and dissolved microcystin‐LR concentration following exposure to plant‐producing phenols
Authors: Dziga Dariusz , Suda Magdalena , Bialczyk Jan , Czaja‐Prokop Urszula , Lechowski Zbigniew 
Published: July 2007

AbstractPlant‐producing phenols could strongly inhibit the growth of toxic cyanobacteria genera, but the ecological consequences of this action are still unknown. In this work, the activity of selected phenols in relation to the strain Microcystis aeruginosa was investigated. We have found that the mechanism of the growth inhibition could involve both the inhibition of the photosynthetic system and the alkaline phosphatase activity. The excretion of a high amount of microcystin‐LR to the environment was observed as a final result of the application of phenols to the cyanobacterial culture. This finding suggests that first of all an algicidal effect of phenols was probably the reason of the cyanobacterial biomass decreasing. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 341–346, 2007.
Summer learning and its implications: Insights from the Beginning School Study
Authors: Alexander Karl L. , Entwisle Doris R. , Olson Linda Steffel 
Published: July 2007

AbstractThere is perhaps no more pressing issue in school policy today than the achievement gap across social lines. Achievement differences between well‐to‐do children and poor children and between disadvantaged racial and ethnic minorities and majority whites are large when children first begin school, and they increase over time. Despite years of study and an abundance of good intentions, these patterned achievement differences persist, but who is responsible, and how are schools implicated? The increasing gap seems to suggest that schools are unable to equalize educational opportunity or, worse still, that they actively handicap disadvantaged children. But a seasonal perspective on learning yields a rather different impression. Comparing achievement gains separately over the school year and the summer months reveals that much of the achievement gap originates over the summer period, when children are not in school. The authors review Beginning School Study research on differential summer learning across social lines (that is, by family socioeconomic level) and its implications for later schooling outcomes, including high school curriculum placements, high school dropout, and college attendance. These studies document the extent to which these large summer learning differences impede the later educational progress of children of low socioeconomic status. Practical implications are discussed, including the need for early and sustained interventions to prevent the achievement gap from opening wide in the first place and for high‐quality summer programming focused on preventing differential summer learning loss.
Summer library reading programs
Authors: Fiore Carole D. 
Published: July 2007

AbstractVirtually all public libraries in the United States provide some type of summer library reading program during the traditional summer vacation period. Summer library reading programs provide opportunities for students of many ages and abilities to practice their reading skills and maintain skills that are developed during the school year. Fiore summarizes some of the research in the field and relates it to library programs and usage by students. Several traditional and innovative programs from U.S. and Canadian libraries are described. She concludes with a call for further research related to summer library reading programs.
Detection of Argan Oil Adulteration Using Quantitative Campesterol GC‐Analysis
Authors: Hilali Miloudi , Charrouf Zoubida , Soulhi Abd El Aziz , Hachimi Larbi , Guillaume Dominique 
Published: July 2007

AbstractDetection of edible oil adulteration is of utmost important to ensure product quality and customer protection. Campesterol, a sterol found in seed oils, represents less than 0.4% of argan oil total sterol content. Quantitative analysis of campesterol by gas chromatography of argan oil and of a mixture of argan oil and readily commercially available vegetable oils, consecutively with sterol separation, was carried out. Our study clearly demonstrated that determination of the campesterol level in argan oil (or oil presented as argan oil) can be proposed as the major analysis method to assess unambiguously argan oil purity up to 98%.
Fatty Acid Composition and Oil Yield in Fruits of Five Arecaceae Species Grown in Cuba
Authors: Rodríguez‐Leyes Eduardo A. , Canavaciolo Víctor L. González , Delange David Marrero , Enríquez Abel R. Sgambelluri , Fajardo Yuliamny Adames 
Published: July 2007

AbstractThe present study targeted the whole‐fruit oil yield and fatty acid composition from five of the most abundant Arecaceae species grown in Cuba. The oil yields (% dry weight), determined by the Soxhlet extraction technique with hexane, were 25.5, 5.3, 6.9, 5.4, and 6.4% for Roystonea regia, Colpothrinax wrightii, Sabal maritima, Sabal palmetto and Thrinax radiata, respectively. The free fatty acid (FFA) content varied from 2.7 to 6.8%. Fatty acid (FA) profiles of the oils indicated that lauric acid (13.7–44.4%), myristic acid (9.4–22.4%) and palmitic acid (9.2–17.1%) as major saturated FA; whereas oleic acid (9.6–42.7%) and linoleic acid (9.3–17.0%) as major unsaturated FA. R. regia fruit seemed the most promising among Arecaceae grown in Cuba because of its high oil yield and low oil FFA content.
Comparing methods for handling missing values in food-frequency questionnaires and proposing k nearest neighbours imputation: effects on dietary intake in the Norwegian Women and Cancer study (NOWAC)
Authors: Parr Christine L , Hjartåker Anette , Scheel Ida , Lund Eiliv , Laake Petter , Veierød Marit B 
Published: July 2007

AbstractObjectiveTo investigate item non-response in a postal food-frequency questionnaire (FFQ), and to assess the effect of substituting/imputing missing values on dietary intake levels in the Norwegian Women and Cancer study (NOWAC). We have adapted and probably for the first time applied k nearest neighbours (KNN) imputation to FFQ data.DesignData from a recent reproducibility study were used. The FFQ was mailed twice (test–retest) about 3 months apart to the same subjects. Missing responses in the test FFQ were imputed using the null value (frequencies = null, amount = smallest), the sample mode, the sample median, KNN, and retest values.SettingA methodological substudy of NOWAC, a national population-based cohort.SubjectsA random sample of 2000 women aged 46–75 years was drawn from the cohort in 2002 (response 75%). The imputation methods were compared for 1430 women who completed at least 50% of the test FFQ.ResultsWe imputed 16% missing values in the overall test data matrix. Compared to null value imputation, the largest differences in estimated dietary intake were seen for KNN, and for food items with a high proportion of missing. Imputation with retest values increased total energy intake, indicating that not all missing values are caused by respondents failing to specify no consumption, and that null value imputation may lead to underestimation and misclassification.ConclusionMissing values in FFQs present a methodological challenge. We encourage the application and evaluation of newer imputation methods, including KNN, which may reduce imputation errors and give more accurate intake estimates.
Implementing accountability for reasonableness – the case of pharmaceutical reimbursement in Sweden
Authors: JANSSON SANDRA 
Published: July 2007

AbstractThis paper aims to describe the priority-setting procedure for new original pharmaceuticals practiced by the Swedish Pharmaceutical Benefits Board (LFN), to analyse the outcome of the procedure in terms of decisions and the relative importance of ethical principles, and to examine the reactions of stakeholders. All the ‘principally important’ decisions made by the LFN during its first 33 months of operation were analysed. The study is theoretically anchored in the theory of fair and legitimate priority-setting procedures by Daniels and Sabin, and is based on public documents, media articles, and semi-structured interviews. Only nine cases resulted in a rejection of a subsidy by the LFN and 15 in a limited or conditional subsidy. Total rejections rather than limitations gave rise to actions by stakeholders. Primarily, the principle of cost-effectiveness was used when limiting/conditioning or totally rejecting a subsidy. This study suggests that implementing a priority-setting process that fulfils the conditions of accountability for reasonableness can result in a priority-setting process which is generally perceived as fair and legitimate by the major stakeholders and may increase social learning in terms of accepting the necessity of priority setting in health care. The principle of cost-effectiveness increased in importance when the demand for openness and transparency increased.
Sch35966 is a potent, selective agonist at the peripheral cannabinoid receptor (CB2) in rodents and primates
Authors: Gonsiorek W , Lunn C A , Fan X , Deno G , Kozlowski J , Hipkin R W 
Published: July 2007

Background and purpose:The peripheral cannabinoid receptor (CB2) is expressed on peripheral immune cells and is thought to have a role in the immunosuppressive effects of cannabinoids. Historically, there have been few potent, CB2‐selective agonists to assess the contribution of CB2to this phenomenon. The studies presented here describe the synthesis of 8,10‐bis[(2,2‐dimethyl‐1‐oxopropyl)oxy]‐11‐methyl‐1234‐tetrahydro‐6H‐benzo[β]quinolizin‐6‐one (Sch35966), which binds with low nanomolar potency to CB2in both primates and rodents.Experimental approach:The affinity, potency and efficacy of Sch35966 and other cannabinoid ligands at CB2was assessed using competition binding assays vs [3H]CP55,940, [35S]GTPγS exchange, cAMP accumulation and cell chemotaxis assays.Key results:We showed that Sch35966 has >450‐fold selectivity for CB2binding vs the central cannabinoid receptor (CB1) in primates (humans and cynomolgus monkeys) and rodents (rats and mice). Sch35966 is an agonist as it effectively inhibited forskolin‐stimulated cAMP synthesis in CHO‐hCB2cells, stimulated [35S]GTPγS exchange and directed chemotaxis in cell membranes expressing CB2. In all species examined, Sch35966 was more potent, more efficacious and more selective than JWH‐015 (a commonly used CB2‐selective agonist).Conclusions and implications:Taken together, the data show that Sch35966 is a potent and efficacious CB2‐selective agonist in rodents and primates.British Journal of Pharmacology(2007)151, 1262–1271; doi:10.1038/sj.bjp.0707336
The potential of high‐content high‐throughput microscopy in drug discovery
Authors: Starkuviene V , Pepperkok R 
Published: July 2007

Fluorescence microscopy is a powerful method to study protein function in its natural habitat, the living cell. With the availability of the green fluorescent protein and its spectral variants, almost any gene of interest can be fluorescently labelled in living cells opening the possibility to study protein localization, dynamics and interactions. The emergence of automated cellular systems allows rapid visualization of large groups of cells and phenotypic analysis in a quantitative manner. Here, we discuss recent advances in high‐content high‐throughput microscopy and its potential application to several steps of the drug discovery process.British Journal of Pharmacology (2007) 152, 62–71; doi:10.1038/sj.bjp.0707346
In vitroandin vivoantiproliferative and trypanocidal activities of ruthenium NO donors
Authors: Silva J J N , Osakabe A L , Pavanelli W R , Silva J S , Franco D W 
Published: July 2007

Background and purpose:Many compounds liberating NO (NO donors) have been used as therapeutic agents. Here we test two ruthenium nitrosyls, which release NO when activated by biological reducing agents, for their effectsin vitroandin vivoagainstTrypanasoma cruzi, the agent responsible for the American trypanosomiasis (Chagas’ disease).Experimental approach:Ruthenium NO donors were incubated with a partially drug‐resistant strain ofT. cruziand the anti‐proliferative and trypanocidal activities evaluated. In a mouse model of acute Chagas’ disease, trypanocidal activity was evaluated by measuring parasitemia, survival rate of infected mice and elimination of amastigotes in myocardial tissue.Key results:In vitro, the observed anti‐proliferative and trypanocidal activities of trans‐[Ru(NO)(NH3)4isn](BF4)3andtrans‐[Ru(NO)(NH3)4imN](BF4)3were due to NO liberated upon reduction of these nitrosyls. Ru(NO)isn had a lower IC50epi(67μM) than the NO donor, sodium nitroprusside (IC50epi=244μM) and Ru(NO)imN (IC50try=52μM) was more potent than gentian violet (IC50try=536μM), currently used in the treatment of blood. Both ruthenium nitrosyls eliminated,in vivo, extracellular as well as intracellular forms ofT. cruziin the bloodstream and myocardial tissue and allowed survival of up to 80% of infected mice at a dose (100 nmol kg−1day−1) much lower than the optimal dose for benznidazole (385μmol kg−1day−1).Conclusions and implications:Our data strongly suggest that NO liberated is responsible for the anti‐proliferative and trypanocidal activities of the ruthenium NO donors and that these compounds are promising leads for novel and effective anti‐parasitic drugs.British Journal of Pharmacology(2007)152, 112–121; doi:10.1038/sj.bjp.0707363