bluuebunny/crossref_metadata_2025_split huggingface dataset:
Self‐assembled Si nanostripe grating at the molecular scale as a template for 1D growth
Authors: Sahaf H. , Dettoni F. , Léandri C. , Moyen E. , Masson L. , Hanbücken M. 
Published: April 2010

AbstractAt room temperature, the early stages (submonolayer) of silicon (Si) deposition onto the anisotropic Ag(110) surface lead to the formation of flat‐lying, individual Si nanostripes, with a high aspect ratio, all oriented along the Ag[−100] direction. Two kinds of nanostripes, varying in their width, are observed. When deposited at ∼200 °C, these one‐dimensional (1D) nanostructures self‐assemble laterally, to form a perfect 1D‐array of essentially identical nanowires, 1.6 nm in width. They cover uniformly the entire Ag substrate up to macroscopic sizes. The self‐assembled Si nanostripes have been characterized by high‐resolution scanning tunneling microscopy (STM), and a model of their atomic arrangement is proposed. This Si grating has been subsequently used as a template for selective 1D growth of 1D Co nanolines. Copyright © 2010 John Wiley & Sons, Ltd.
Simulation of parallel angle‐resolved X‐ray photoelectron spectroscopy data
Authors: Tasneem G. , Werner W. S. M. , Smekal W. , Powell C. J. 
Published: April 2010

AbstractThe effects of elastic scattering and photoionization anisotropy have been studied for angle‐resolved XPS (ARXPS) instruments in which the angular distribution is measured for a fixed sample geometry, in contrast to conventional ARXPS in which the sample is tilted for angular variation. The analyzed data were generated by the National Institute of Standards and Technologydatabase for the Simulation of Electron Spectra for Surface Analysis, which provides a simple way to study the influence of the aforementioned effects on compositional depth profile reconstruction. The abovementioned effects have been studied for a 15‐Å film of SiO2 on Si covered by a 5‐Å carbon contamination layer. For this sample, the effects of anisotropy were stronger than the effects of elastic scattering. Larger effects of elastic scattering have been observed for HfO2 sample. Copyright © 2010 John Wiley & Sons, Ltd.
XANES, USXES and XPS investigations of electron energy and atomic structure peculiarities of the silicon suboxide thin film surface layers containing Si nanocrystals
Authors: Terekhov V. A. , Turishchev S. Yu. , Pankov K. N. , Zanin I. E. , Domashevskaya E. P. , Tetelbaum D. I. , Mikhailov A. N. , Belov A. I. , Nikolichev D. E. , Zubkov S. Yu. 
Published: April 2010

AbstractFilms obtained using molecular‐beam deposition of SiO powder on c‐Si (111) substrates for the purpose of SiO2 system formation with silicon nanocrystals were investigated before and after 900–1100 °C annealing by photoluminescence, ultrasoft X‐ray emission spectroscopy, X‐ray photoelectron spectroscopy, X‐ray absorption near edge structure spectroscopy and X‐ray diffraction. The appearance of (111) oriented luminescent silicon nanoclusters in considerable amounts on annealing at 1000–1100 °C is established in the investigated films. An anomalous phenomenon of the X‐ray absorption quantum yield intensity inversing for the L2, 3 elementary silicon edge is detected. Models for this phenomenon are suggested. Copyright © 2010 John Wiley & Sons, Ltd.
Photoemission and thermo‐programmed reaction study of the catalytic properties of Rh/CeO2 system
Authors: Nehasil Václav , Ševčíková Klára , Zahoranová Tatiana 
Published: April 2010

AbstractRhodium deposited onto thin films of cerium dioxide was exposed by molecular beams of CO and O2. Production of CO2 was studied as a function of the substrate temperature and structure and the oxidation state of the samples. Polycrystalline CeO2 films as well as oriented CeO2(111)/Cu(111) ones were used. The results show that CO2 production depends on the original conditions of the used samples. Morphology of their surface (oriented or polycrystalline) as well as their chemical state (oxidised or reduced) is important. The observed effects are discussed with a respect to the X‐ray photoelectron spectra obtained at particular steps of the experiment. Copyright © 2010 John Wiley & Sons, Ltd.
Illumination effect on I‐V, C‐V and G/w‐V characteristics of AlTiWPd2Si/nSi structures at room temperature
Authors: Uslu H. , Dökme İ. , Afandiyeva I. M. , Altındal Ş. 
Published: April 2010

AbstractIn this study, the forward and reverse bias current‐voltage (I‐V), capacitance‐voltage (C‐V) and conductance‐voltage (G/w‐V) characteristics of AlTiWPd2Si/nSi structures were measured at room temperature. In order to see the illumination effect on main structure parameters such as zero‐bias‐barrier height (ΦBo), ideality factor (n), series resistance (Rs) of structure and interface states (Nss), the forward and reverse bias I‐V, C‐V and G/w‐V characteristics of AlTiWPd2Si/nSi structures were investigated in the dark and under various levels of illumination. These main electrical parameters were obtained as function of illumination levels from these measurements. Experimental results show that both the C and G values increase with increasing illumination level due to the illumination‐induced interface states. Also, the value of Rs decreases with increasing illumination level. The Nss profile was obtained for both forward bias I‐V characteristics by taking into account the bias dependent of the ideality factor and effective barrier height (Φe) and low‐high frequency method. Copyright © 2010 John Wiley & Sons, Ltd.
The influence of explicit nature of science and argumentation instruction on preservice primary teachers' views of nature of science
Authors: McDonald Christine V. 
Published: April 2010

AbstractThere exists a general consensus in the science education literature around the goal of enhancing learners' views of nature of science (NOS). An extensive body of research in the field has highlighted the effectiveness of explicit NOS instructional approaches in improving learners' NOS views. Emerging research has suggested that engaging learners in argumentation may aid in the development of their NOS views, although this claim lacks empirical support. This study assessed the influence of a science content course incorporating explicit NOS and argumentation instruction on five preservice primary teachers' views of NOS using multiple sources of data including questionnaires and surveys, interviews, audio‐ and video‐taped class sessions, and written artifacts. Results indicated that the science content course was effective in enabling four of the five participants' views of NOS to be improved. A critical analysis of the effectiveness of the various course components led to the identification of three factors that mediated the development of participants' NOS views during the intervention: (a) contextual factors (context of argumentation, mode of argumentation), (b) task‐specific factors (argumentation scaffolds, epistemological probes, consideration of alternative data and explanations), and (c) personal factors (perceived previous knowledge about NOS, appreciation of the importance and utility value of NOS, durability and persistence of pre‐existing beliefs). The results of this study provide evidence to support the inclusion of explicit NOS and argumentation instruction as a context for learning about NOS, and promote consideration of this instructional approach in future studies which aim to enhance learners' views of NOS. © 2010 Wiley Periodicals, Inc. J Res Sci Teach 47: 1137–1164, 2010
Translating expertise into effective instruction: The impacts of cognitive task analysis (CTA) on lab report quality and student retention in the biological sciences
Authors: Feldon David F. , Timmerman Briana Crotwell , Stowe Kirk A. , Showman Richard 
Published: April 2010

AbstractPoor instruction has been cited as a primary cause of attrition from STEM majors and a major obstacle to learning for those who stay [Seymour and Hewitt [1997]. Talking about leaving: Why undergraduates leave the sciences. Boulder, CO: Westview]. Using a double‐blind design, this study tests the hypothesis that the lack of explicit instructions in scientific inquiry skills is a major factor in both low STEM retention and academic underperformance. This project delivered supplemental instruction to students in a laboratory‐based undergraduate biology course (n = 314) that was derived either from cognitive task analyses (CTAs) conducted with expert biologists (treatment) or was authored and delivered by an award‐winning biology instructor (control). Students receiving traditional instruction were almost six times more likely to withdraw from the course than students in the treatment condition (8.1% vs. 1.4% of initial enrollment). Of the students who completed the course, those who received the CTA‐based instruction demonstrated significantly higher levels of performance in the discussion section of their written laboratory reports. Significantly higher performances were seen specifically in the areas of analyzing data to formulate valid conclusions, considering alternative explanations, consideration for the limitations of the experimental design and implications of the research. © 2010 Wiley Periodicals, Inc. J Res Sci Teach 47: 1165–1185, 2010
Dendroclimatology: extracting climate from trees
Authors: Sheppard Paul R. 
Published: April 2010

AbstractThe scientific discipline called dendrochronology is the study of tree rings and of environmental conditions and events of the past that tree growth can reflect. The beginning of scientific study of tree rings is generally ascribed to an astronomer named Andrew Ellicott Douglass, who in the early 1900s noticed not only variation in tree‐ring width but also that this variability was similar between multiple trees. Dendrochronology subsequently expanded worldwide, and now over 3000 of the 12,000+ publications on dendrochronology can be classified as dendroclimatology. As a subfield of tree‐ring analysis, dendroclimatology estimates climate back in time beyond the start of recorded meteorological measurements. Dendroclimatology starts with site and tree selection and continues with dating, measuring, data quality control, and chronology construction. Tree rings are associated with climate using statistical models that are then evaluated for their full length to reconstruct climate of the past. Most commonly, either precipitation or temperature is reconstructed, and reconstructions are then analyzed for frequency of extreme years, changes in mean conditions, ranges of long‐term variability, and changes in interannual variability. For example, from reconstructions of Northern Hemisphere temperature based on tree rings and other natural archives of climate collected from multiple sites, it appears that current temperature (since ad 1850) exceeds the range of variability reconstructed for ad 1000‐1850. Uncertainties in dendroclimatology exist, including a relatively recent issue called divergence, but dendroclimatology has played, and continues to play, a substantial role in interdisciplinary research on climate change. Copyright © 2010 John Wiley & Sons, Ltd.This article is categorized under:

Paleoclimates and Current Trends > Paleoclimate
Governing the carbon offset market
Authors: Lovell Heather C. 
Published: April 2010

AbstractCarbon offsets are produced and sold under the international climate change regime (the United Nations Kyoto Protocol) and also within an expanding voluntary offset market in which companies and individuals can voluntarily opt to compensate for their greenhouse gas emissions. The volume of carbon produced and consumed within compliance and voluntary markets has grown dramatically in the last 5 years, raising a number of governance challenges. This Focus Article gives an overview of the governance of the compliance and voluntary carbon offset markets, and considers the implications of their different governance structures for addressing climate change. It assesses recent changes in the governance of the voluntary carbon offset market in response to concerns about the credibility and robustness of voluntary carbon offsets. Several voluntary offset standards were launched in 2007–2009, including the Voluntary Carbon Standard and the Gold Standard. National governments have also taken regulatory action on voluntary offsets, notably the UK government who took the controversial decision in early 2009 to endorse only compliance carbon offsets for use in the UK voluntary market. The UK government's attempt to regulate the voluntary offset market provides a useful case through which to explore some of the inherent tensions in effectively governing the carbon offset market. Copyright © 2010 John Wiley & Sons, Ltd.This article is categorized under:

Policy and Governance > Private Governance of Climate Change
Climate policy and action ‘underneath’ Kyoto and Copenhagen: China and the United States
Authors: Koehn Peter 
Published: April 2010

AbstractThis contribution focuses on the role and promise of municipal‐government climate‐stabilization policies in the world's two largest greenhouse gases (GHG)‐emitting nations. The article compares emission‐mitigation authority, drivers, barriers, and activities at the city level in China and the United States. Recent municipal policy initiatives are analyzed within a policy context of climate‐driven and climate‐incidental municipal framings. For the most part, United States and Chinese cities have not yet adopted policy strategies that are intended to address GHG emissions directly and have not provided normative leadership in the interest of ecological justice. In both countries, however, increasingly independent and networked municipal governments are linking a diverse set of activities that focus on air‐quality, health‐promotion, and economic security to emissions reduction. These climate‐incidental municipal policies establish commitments that are beginning to exert an important global environmental impact. Although noteworthy and exemplary in a political context of national resistance to emission mandates, in the absence of a coordinated and strategically framed commitment among cities across both countries and/or policies and targets agreed upon at national and international levels that generate and reinforce local government initiatives, fragmented, uneven, and incomplete municipal‐government actions will continue to exert limited measurable and normative impact on global GHG emissions. Copyright © 2010 John Wiley & Sons, Ltd.This article is categorized under:Policy and Governance > Governing Climate Change in Communities, Cities, and Regions
Downscaling socioeconomic and emissions scenarios for global environmental change research: a review
Authors: van Vuuren Detlef P. , Smith Steve J. , Riahi Keywan 
Published: April 2010

AbstractGlobal change research encompasses various scales from global to local. Impacts analysis in particular often requires spatial downscaling, whereby socioeconomic and emission variables specified at relatively large spatial scales are translated to values at a country or grid level. In this article, the methods used for spatial downscaling are reviewed, classified, and current applications discussed. It is shown that in recent years, improved methods for downscaling have been developed. Copyright © 2010 John Wiley & Sons, Ltd.This article is categorized under:

Assessing Impacts of Climate Change > Scale Issues
A study of the effect of an extremely low oxygen concentration on the development of human embryos in assisted reproductive technology
Authors: Nakagawa Koji , Shirai Asako , Nishi Yayoi , Sugiyama Rie , Kuribayashi Yasushi , Sugiyama Rikikazu , Inoue Masato 
Published: April 2010

AbstractPurposeTo determine whether embryos cultured with a low oxygen level (2%) brought about beneficial effects on the outcome of ART.MethodsThis is a sequential case–control embryo‐culture study. Embryos were cultured either with a gas mixture containing 2% O2, 5% CO2, and 93% N2 (low‐oxygen group) or 5% O2, 5% CO2, and 90% N2 (conventional group). From January 2008 to September 2008, 873 fertilized oocytes were obtained from 250 patients in the low‐oxygen group and from October 2008 to March 2009, 730 fertilized oocytes were obtained from 213 patients in the conventional group. The outcomes of ART were compared between two groups.ResultsThe cleavage rate in the low‐oxygen group (94.4%) was similar to that (94.7%) in the conventional group. The mean number of blastomeres on Day 3 in the low‐oxygen group (mean ± SE) was 6.5 ± 1.9, and this was significantly lower than in the conventional group (6.8 ± 1.9, p < 0.05). Moreover, the low‐oxygen group produced worse quality embryos, on the basis of the significantly higher embryo grade 2.1 ± 0.6 versus 1.9 ± 0.6, p < 0.001, in 5% oxygen. The pregnancy and miscarriage rates in the low‐oxygen group were 22.3 and 20.8%, respectively, which were statistically similar to the outcomes in the conventional group.ConclusionsOverall, culture of embryos at the low oxygen level did not significantly improve ART results compared with embryos grown in 5% oxygen. The study suggests that a low oxygen level worsens embryo morphology but does not impair embryo viability.
Middle ear cholesteatoma
Authors: Fränzer Jürgen-Theodor , Sudhoff Holger 
Published: April 2010

Abstract
Cholesteatomas can originate at various sites on the temporal bone, which houses the middle ear among other structures. Distinc­tion is made between three types of choles­teatoma: auditory canal, middle ear, and pe­trous apex. The most frequent type, middle ear cholesteatoma, can be subdivided into a congenital and an acquired form. A number of theories on the aetiology of this aggres­sive form of middle ear inflammation have been put forward and, in some cases, dis­missed again.
We investigated the role of bacterial in­fection as a trigger in the development of cholesteatomas. For this purpose, we used modern molecular, cellular biological and im­munohistochemical approaches on human biopsy material, since it has not been possi­ble to date to establish an animal model re­sembling the human cholesteatoma. We re­port the different theories on the origin and development of cholesteatomas, as well as the findings to support each of these hypoth­eses. Many investigations into hyperprolifer­ation, the various morphological sections of cholesteatomas, as well as into the expres­sion of different proteins in these areas com­plete the presentation of our work. Finally, we emphasize that there is evidence to indicate that a weakness in the innate antimicrobi­al defense system of the human external ear skin may make a decisive contribution in the development cholesteatomas.
The neuronal network of the endogenous clock
Authors: Förster Charlotte 
Published: April 2010

Abstract
Endogenous clocks control the rhythm of many biological processes. Malfunction of endogenous clocks in humans can lead to various diseases as sleep disorders, depres­sions, the metabolic syndrome and cancer. All animals have a main clock in the brain. This clock comprises a network of clock neurons that communicate with each other. In each clock neuron, conserved clock genes and pro­teins interact in to generate a molecular os­cillation. The molecular basis of this rhythm generation as well as the anatomy of the neuronal clock network is best investigated in the fruit fly Drosophila melanogaster. In the little fly, clock genes can be shut down in specific clock neurons. Furthermore, specific clock neurons can be electrically silenced and the rhythmic behaviour of such manipulated flies can be studied. A flurry of recent studies has begun to identify the role of specific clock neurons in the clock network, and these find­ings are helping to understand the basic neu­ronal mechanisms of endogenous clocks.
TRIANGULATING TECHNOLOGY DIFFUSION INDICATORS: ZERO TILLAGE WHEAT IN SOUTH ASIA'S IRRIGATED PLAINS
Authors: ERENSTEIN OLAF 
Published: April 2010

SUMMARYImpact assessment hinges on reliable indicators of technology uptake, but this poses particular challenges for new agronomic practices in emerging economies. This paper presents a triangulation approach to assess technology diffusion and illustrates it by assessing the extent and dynamics of zero tillage wheat in South Asia's rice-wheat systems. Various diffusion indicators from three different data methods (secondary data, supply-side surveys, demand-side surveys) are contrasted for two different locations (India's Haryana State and Pakistan's Punjab province) for the period 2000–2004. Such multi-indicator, multi-site and multi-year triangulation enhances the robustness of the inferences and provides the necessary perspective. The three sources coincide in terms of diffusion of zero tillage wheat having increased since 2000, but in particular the empirical surveys show a much slower uptake and subsequent stagnation in the Pakistan Punjab study area. The paper thereby reiterates the need for empirical ground truthing of technology uptake and the need for robust and complementary diffusion indicators.
VILLAGE SURVEYS FOR TECHNOLOGY UPTAKE MONITORING: CASE OF TILLAGE DYNAMICS IN THE TRANS-GANGETIC PLAINS
Authors: ERENSTEIN OLAF 
Published: April 2010

SUMMARYAgricultural research and development (R&D) would benefit from reliable yet cheap technology uptake indicators to guide decision making. The paper explores the use of village surveys to monitor technology use and illustrates this through two empirical case studies into tillage dynamics in the Trans-Gangetic Plains in northwest India. The first case study is a revisit of 50 communities surveyed earlier in Haryana State. The second case study is a new and wider representative sample of 120 villages across Haryana and Punjab States. The case studies illustrate that after an initial rapid spread of tractor-drawn zero tillage drills for wheat seeding in these intensive systems, the zero + reduced tillage area seems to have stabilized there at between a fifth and a quarter of the wheat area. Conventional tillage for wheat continues to decline, with an increased use of rotavators making up the difference – but its intensive shallow tillage goes against the conservation agriculture tenets. The paper illustrates the potential of village surveys to provide timely and cost-effective feedback to agricultural R&D.
Kinetic theory of transverse plasmons in pair plasmas
Authors: LIU S. Q. , LIU Y. 
Published: April 2010

AbstractA set of nonlinear governing equations for interactions of transverse plasmons with pair plasmas is derived from Vlasov–Maxwell equations. It is shown the ponderomotive force induced by high-frequency transverse plasmons will expel the pair particles away, resulting in the formation of density cavity in which transverse plasmons are trapped. Numerical results show the envelope of wave fields will collapse and break into a filamentary structure due to the spatially inhomogeneous growth rate. The results obtained would be useful for understanding the nonlinear propagation behavior of intense electromagnetic waves in pair plasmas.