bluuebunny/crossref_metadata_2025 huggingface dataset:
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

Films 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

Rhodium 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

In 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

There 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

Poor 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

The 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

Carbon 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

This 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

Global 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

Purpose

To determine whether embryos cultured with a low oxygen level (2%) brought about beneficial effects on the outcome of ART.

Methods

This 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.

Results

The 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.

Conclusions

Overall, 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

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

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

Impact 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

Agricultural 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.
Optimal linear growth in magnetohydrodynamic duct flow
Authors: KRASNOV DMITRY , ZIKANOV OLEG , ROSSI MAURICE , BOECK THOMAS
Published: April 2010

Transient linear growth in laminar magnetohydrodynamic duct flow is analysed. The duct is straight with rectangular cross-section and electrically insulating walls. The applied uniform magnetic field is oriented perpendicular to the mean flow direction and parallel to one of the walls. Optimal perturbations and their maximum amplifications over finite time intervals are computed. The optimal perturbations are increasingly damped by the magnetic field, localized in the boundary layers parallel to the magnetic field irrespective of the duct aspect ratio. Typically, the optimal perturbations have non-vanishing streamwise wavenumber as found in magnetohydrodynamic channel flow with spanwise magnetic field. The Hartmann boundary layers perpendicular to the magnetic field do not contribute to the transient growth.
Kinetic theory of transverse plasmons in pair plasmas
Authors: LIU S. Q. , LIU Y.
Published: April 2010

A 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.
Palio dubia (Nudibranchia: Doridina) from the north-west Atlantic Ocean: is its morphology at hatching consistent with settlement one day later?
Authors: Goddard Jeffrey H.R.
Published: April 2010

Hamel et al. (2008) reported that veliger larvae of the nudibranch gastropod Palio dubia settled 1 to 3 days after hatching and that metamorphosis commenced shortly thereafter. This is an anomalously short larval period for a nudibranch described as having planktotrophic development. I examined the embryonic development and hatching larvae of P. dubia collected intertidally from Maine, USA. Veliger larvae with shells 120 μm long and lacking eyespots and propodia developed in 7 days at 20°C from eggs averaging 69 μm in diameter. Their size and morphology were typical of planktotrophic nudibranchs known to have minimum larval periods of weeks to months, and the available evidence does not suggest any other mode of development exists in P. dubia. The larval period of P. dubia is likely an order of magnitude longer than reported by Hamel et al. (2008).
Embryonic development and spawning pattern of Trisopterus luscus (Teleostei: Gadidae) under controlled conditions
Authors: Alonso-Fernández Alexandre , Vergara Alba Ruth , Saborido-Rey Fran
Published: April 2010

Knowledge on early ontogeny of Trisopterus luscus is scarce and incomplete. This paper describes the first successful attempt ever at achieving the natural spawning in captivity for this species. The reproductive specimens used for this study were obtained in the Ría de Vigo in September 2008 and subsequently transported to the facilities of the Institute of Marine Research (CSIC). The spawning frequency was variable among females, 1.8–4.6 days, but no size-dependent trend was determined. The average batch size, i.e. the number of eggs released per batch, has proven significantly dependent on female length and weight. In the present study the complete embryonic development in controlled conditions (sand–filtered seawater at ~13°C, with natural photoperiod), from egg to hatched larva, has been described for the first time ever. The development of pouting eggs was divided into six stages, based on the artificially-reared material. Pouting eggs are pelagic with a smooth, clear and spherical chorion, and a homogeneous yolk. The perivitelline space is narrow and oil globules are absent. Live eggs fertilized were 0.95–1.10 mm in diameter. The embryo hatches as a yolk-sac larva with closed mouth and gut. The pouting eggs hatched during the latter half of the fifth day.
Ecological considerations and niche differentiation between juvenile and adult black limpets (Cymbula nigra)
Authors: Rivera-Ingraham G.A. , Espinosa F. , García-Gómez J.C.
Published: April 2010

The endangered patellid limpet Cymbula nigra is present in the extreme western Mediterranean, yet the species has rarely been the subject of study in this region. The aim of the present research is to describe the ecology, distribution and population structure of the species in an area of the Mediterranean coast of North Africa (Ceuta). Results indicate that the species prevails in waters that have an important Atlantic influence. Furthermore, different shell morphologies are distinguished, and in consequence, a statistical analysis is carried out based on morphometric data. Based on maximum shell length, height/length coefficients and shell morphology, a total of three significantly different morphologies are described. Furthermore, considering physical parameters such as height over seawater level and average substratum inclination, juveniles resulted to be clearly segregated from the two other groups. Additionally, no differences were found regarding the topography of the substrate used by juvenile and adult individuals, although the colonized surfaces are significantly smoother than those where Patella ferruginea is present.
Maturity index validation in the white-spotted skateBathyraja albomaculata, from the Falkland Islands
Authors: Henderson A.C. , Arkhipkin A.I.
Published: April 2010

The reproductive systems of 39 male and 54 femaleBathyraja albomaculatawere assessed microscopically and compared with macroscopic maturity index values assigned by scientific observers. Inconsistencies were limited to ‘developing’ maturity stages in both sexes, but such discrepancies were attributed to different factors depending on sex. Furthermore, while spermatozoa were observed in the oviducal gland of females, they do not appear to accommodate long-term sperm storage in this species.
Study on the behaviour of two fiddler crabs, Uca sindensis and Uca annulipes (Decapoda: Ocypodidae), in Bandar Abbas, Iran
Authors: Mokhlesi Amin , Kamrani Ehsan , Backwell Patricia , Sajjadi Mirmasoud
Published: April 2010

This study was carried out on the behaviour of two species of sympatric fiddler crabs on Abi estuary, Bandar Abbas, Iran. Species differences in activity level, grooming, burrowing, muddy structure construction and feeding were all related to their habitat and food source. The more common Uca annulipes lives in low muddy areas along the edges of small streams while Uca sindensis lives in small patches on the higher areas with sandier sediment. At low tide, both species spent most of their time feeding, while at high tide they retreated into their burrows. Both species frequently walked while feeding and interacted aggressively. There were similarities in the feeding behaviour of these species: they fed at the same times of the tidal cycles, they were more likely to engage in courtship and mating behaviour during February–September and were least aggressive at this time. In both species, crabs excavated mud balls from their burrows and placed them away from their burrow entrances. There were, however, also differences between the species. Uca annulipes constructed mud hoods at the entrance to their burrows while U. sindensis did not; and the species differed in feeding rate.
Feeding ecology of the green sea turtle (Chelonia mydas) in the Galapagos Islands
Authors: Carrión-Cortez Javier A. , Zárate Patricia , Seminoff Jeffrey A.
Published: April 2010

The Galapagos Islands are among the most important nesting areas for the green sea turtle, Chelonia mydas, in the eastern Pacific Ocean. In addition, the coastal waters of this oceanic archipelago host many important feeding areas for this species, although little is known about green turtle feeding ecology at these sites. The goal of this study was to identify and quantify the most important items in the diet of the green turtle at the foraging grounds of Bahia Elizabeth, Caleta Derek and Punta Nuñez. Our analysis was based on 65 oesophageal samples from turtles captured in 2006 and 2007. We compared spatial and seasonal composition of diet using non-metric multidimensional scaling analysis (MDS) and analysis of similarity (ANOSIM). Green turtle diet was composed mainly of the algae species Ulva lactuca, Polysiphonia sp., Hypnea sp. and Dictyota sp., and the red mangrove Rhizophora mangle. Turtles also consumed animal matter, mainly cnidarians, albeit to a lesser extent. Content of turtle diets was different among feeding grounds and seasons. The ANOSIM showed that diet composition can differ between foraging grounds using presence/absence of diet items. Even though U. lactuca was the most abundant algae consumed in both seasons, changes in species richness of algae were found between both sampling events, with diet during the warm season more varied than the cold season (χ2 = 16.84, df = 6; P < 0.05).
Polychaete assemblages in the south-eastern Bering Sea: linkage with groundfish distribution and diet
Authors: Yeung Cynthia , Yang Mei-Sun , McConnaughey Robert A.
Published: April 2010

Ecological information on the polychaete community may improve habitat descriptions and distribution models of commercially important species that are polychaete-feeders. This study reports on the first new observations in nearly three decades on the polychaete assemblages in the south-eastern Bering Sea. This information was used in an exploratory assessment of the association between polychaete assemblages and environmental variables that define the benthic habitat. The spatial association between polychaete assemblages and groundfish predators was also explored for insight into whether prey assemblages influence predator distribution. Canonical correspondence analysis indicates that surficial sediment is the most important factor in organizing polychaete assemblages, over other common environmental variables such as depth and temperature. Co-correspondence analysis of the distributions of groundfish species and polychaete families does not indicate that predators are associated with specific prey families. Families that are most frequent in stomach contents of some of the fish in the analysis, mainly Maldanidae and Nephtyidae, are widely distributed across the Bering Sea shelf in diverse sediment types, as are the principal polychaete-feeders in the eastern Bering Sea such as Alaska plaice (Pleuronectes quadrituberculatus) and northern rock sole (Lepidopsetta polyxystra).
V1 orientation plasticity is explained by broadly tuned feedforward inputs and intracortical sharpening
Authors: TEICH ANDREW F. , QIAN NING
Published: April 2010

Orientation adaptation and perceptual learning change orientation tuning curves of V1 cells. Adaptation shifts tuning curve peaks away from the adapted orientation, reduces tuning curve slopes near the adapted orientation, and increases the responses on the far flank of tuning curves. Learning an orientation discrimination task increases tuning curve slopes near the trained orientation. These changes have been explained previously in a recurrent model (RM) of orientation selectivity. However, the RM generates only complex cells when they are well tuned, so that there is currently no model of orientation plasticity for simple cells. In addition, some feedforward models, such as the modified feedforward model (MFM), also contain recurrent cortical excitation, and it is unknown whether they can explain plasticity. Here, we compare plasticity in the MFM, which simulates simple cells, and a recent modification of the RM (MRM), which displays a continuum of simple-to-complex characteristics. Both pre- and postsynaptic-based modifications of the recurrent and feedforward connections in the models are investigated. The MRM can account for all the learning- and adaptation-induced plasticity, for both simple and complex cells, while the MFM cannot. The key features from the MRM required for explaining plasticity are broadly tuned feedforward inputs and sharpening by a Mexican hat intracortical interaction profile. The mere presence of recurrent cortical interactions in feedforward models like the MFM is insufficient; such models have more rigid tuning curves. We predict that the plastic properties must be absent for cells whose orientation tuning arises from a feedforward mechanism.
Prosodic fusion and minimality in Kabardian
Authors: Gordon Matthew , Applebaum Ayla
Published: April 2010

The Northwest Caucasian language Kabardian displays a typologically unusual process of word formation, whereby two lexical roots fuse to form a single prosodic word whose phonological behaviour is parallel to prosodic words containing a single root. It is shown that this process of fusion, which is subject to a number of phonological and morphosyntactic restrictions, reflects a typologically unusual response to a cross-linguistically common minimal word requirement banning monomoraic prosodic words. Rather than employing segmental lengthening or insertion to ensure that minimality is satisfied, Kabardian chooses to violate the one-to-one mapping between grammatical and prosodic words. A further complication is the scalar nature of minimality in Kabardian: while the impossibility of fusion in certain prosodic and morphosyntactic contexts allows monomoraic prosodic words to surface, a more stringent minimality restriction ensures that all prosodic words have at least one mora.
Hölder continuous potentials on manifolds with partially positive curvature
Authors: Dinew Sławomir
Published: April 2010

It is proved that solutions of the complex Monge–Ampère equation on compact Kähler manifolds with right hand side in Lp, p > 1, are uniformly Hölder continuous under the assumption on non-negative orthogonal bisectional curvature.
On the adjoint quotient of Chevalley groups over arbitrary base schemes
Authors: Chaput Pierre-Emmanuel , Romagny Matthieu
Published: April 2010

For a split semisimple Chevalley group scheme G with Lie algebra $\mathfrak{g}$ over an arbitrary base scheme S, we consider the quotient of $\mathfrak{g} by the adjoint action of G. We study in detail the structure of $\mathfrak{g} over S. Given a maximal torus T with Lie algebra $\mathfrak{t}$ and associated Weyl group W, we show that the Chevalley morphism π : $\mathfrak{t}$/W → $\mathfrak{g}/G is an isomorphism except for the group Sp2n over a base with 2-torsion. In this case this morphism is only dominant and we compute it explicitly. We compute the adjoint quotient in some other classical cases, yielding examples where the formation of the quotient $\mathfrak{g} → \mathfrak{g}//G commutes, or does not commute, with base change on S.
Situations-Reaktions-Fragebogen zur Messung elterlicher Sensitivität (PS-SRQ)
Authors: Hänggi Yves , Schweinberger Kirsten , Gugger Nicole , Perrez Meinrad
Published: April 2010

Zusammenfassung. Die elterliche Sensitivität gegenüber Kleinkindern als zentrale Erziehungsfertigkeit wurde bisher vorwiegend durch Fremdbeobachtungsverfahren ermittelt. Für die Forschung und klinische Praxis werden jedoch zeitökonomische Paper-Pencil-Verfahren gefordert. Der Situations-Reaktions-Fragebogen zur Messung elterlicher Sensitivität (PS-SRQ) ist ein Selbstbeurteilungsinstrument mit drei Situationsvignetten und verhaltensorientiertem Antwortformat. Gemessen werden die vier Subskalen „Empathie”, „Promptheit”, „Zuwendung” und „Bestrafung” als Komponenten der Gesamtskala „Sensitivität”. Es werden drei Studien zur Konstruktion, Reliabilität und internen Validität präsentiert. Zusammenfassend verfügt der PS-SRQ über eine hohe interne Konsistenz und hat sich für Mütter als intern valide erwiesen. Für die Gruppe der Väter steht der Nachweis der Konstruktvalidität noch aus. Der PS-SRQ ist daher ein vielversprechendes Selbstbeurteilungsinstrument zur Erfassung der mütterlichen Sensitivität.
Multimethodale Diagnostik sozialer Kompetenz lernbehinderter Jugendlicher und junger Erwachsener
Authors: Nestler Judith , Goldbeck Lutz
Published: April 2010

Zusammenfassung. In dieser Studie wird ein Ansatz zur mehrdimensionalen und mehrperspektivischen Diagnostik sozialer Kompetenz lernbehinderter Jugendlicher dargestellt. 77 lernbehinderte Jugendliche aus zwei Zentren für berufliche Rehabilitation wurden per Selbst- und Fremdeinschätzung untersucht. Dabei wurden als Selbstbeurteilungsverfahren der Unsicherheitsfragebogen, das Teenage Inventory of Social Skills sowie der Youth Self Report 11-18 verwendet, ergänzend wurde eine Fremdbeurteilung mit der Child Behavior Checklist 4-18, dem Teilmodul 3 „Soziale Kompetenz” des Handlungsorientierten Moduls zur Erfassung und Förderung beruflicher Kompetenzen und dem Beobachtungskategoriensystem Aggressives, Kompetentes und Initiativloses Verhalten erhoben. Reliabilität und Validität der einzelnen Instrumente wurden überprüft, mittels einer Faktorenanalyse wurden Sekundärdimensionen sozialer Kompetenz identifiziert. Die Ergebnisse zeigen, dass die internen Konsistenzen einiger, jedoch nicht aller Skalen überwiegend zufriedenstellend waren. Skaleninterkorrelationen traten in erwarteter Richtung auf. Die Faktorenanalyse ergab eine Reduktion auf fünf Faktoren sozialer Kompetenz. Die Ergebnisse stützen die Mehrdimensionalität des Konstrukts soziale Kompetenz. Insbesondere erwiesen sich kompetentes und problematisches Sozialverhalten als voneinander unabhängige Dimensionen.
Easier When Done Than Said!
Authors: Rudolph Almut , Schröder-Abé Michela , Riketta ✝ Michael , Schütz Astrid
Published: April 2010

Evidence for the criterion validity of indirect self-esteem measures is still limited, with only some studies finding effects of implicit (ISE) independent of explicit (ESE) self-esteem. This may be due to the fact that studies predicting actual behavior are particularly rare. The present study contributes evidence to the predictive validity of the Implicit Association Test and a recently developed self-judgment task under cognitive load. We used criteria beyond self-report: experimenter ratings of anxiety, linguistic aspects of anxiety, and spontaneous self-confident behaviors. Using paired criteria, we tested a double dissociation of ISE and ESE. Results supported our hypothesis: ISE predicted self-confident behaviors or aspects of anxiety that ESE was not able to predict, and vice versa. Thus, differential predictive validity of both measures of self-esteem was demonstrated. With behavioral criteria that tapped into impulsive processes, ISE was a better predictor than ESE was.
Convergence of Direct, Indirect, and Objective Risk-Taking Measures in Gambling
Authors: Dislich Friederike X. R. , Zinkernagel Axel , Ortner Tuulia M. , Schmitt Manfred
Published: April 2010

Based on dual-process models, we assumed that risk taking depends on implicit and explicit risk attitudes and risk propensity. Specifically, we predicted that the convergence between these indicators would depend on the impulsiveness versus reflectiveness of risk behavior. Two objective personality tests (OPTs) of risk taking that measure risk behavior in standardized situations were employed. We predicted that the impulsive OPT would depend more on implicit risk dispositions. The reverse effect pattern was expected for the reflective OPT. Next, we expected that self-control would amplify the weight of explicit dispositions and attenuate that of implicit dispositions. At Time 1, two direct questionnaire measures of explicit risk proneness, three indirect measures of implicit risk proneness, and a self-control measure were administered. At Time 2, participants participated in a reflective and an impulsive gambling OPT. The assumed pattern of effects was obtained. We conclude with a discussion of future research avenues.
Prejudiced or Just Smart?
Authors: von Stülpnagel Rul , Steffens Melanie C.
Published: April 2010

Implicit Association Tests (IATs) are well-known measures of implicit cognition, particularly attitudes. Previous studies reported that IATs are affected by method-specific variance: IAT effects of more intelligent people may appear smaller due to their reduced task-switch costs. In contrast, based on a theoretical framework that assumes IAT effects to depend on successful recoding of the congruent IAT task, larger IAT effects are expected for more intelligent people. We tested the hypothesis that intelligence can bias IAT effects with different IATs. General processing speed was also assessed. Two studies indicated faster and more intelligent participants to have larger IAT effects in some, but not all, IATs.
An attempt to quantify the impact of changes in wetland extent on methane emissions on the seasonal and interannual time scales
Authors: Ringeval Bruno , de Noblet‐Ducoudré Nathalie , Ciais Philippe , Bousquet Philippe , Prigent Catherine , Papa Fabrice , Rossow William B.
Published: April 2010

Climate variability impacts CH4 wetland sources as changes in flux density per unit area and via expansion or contraction of wetland areas in response to surface hydrological processes. This paper is a first attempt to isolate the role of varying wetland area on the seasonal and interannual variability of CH4 wetland emissions over the past decade. Wetland area extent at monthly intervals was provided over the period 1993–2000 by a suite of satellite observations from multiple sensors. The regionally variable fraction of wetland area was optimized using satellite observations of flooded area as a first estimate and further adjusted to match the seasonal cycle of CH4 fluxes retrieved from a global atmospheric inversion. Wetland flux densities of CH4 were calculated by coupling the ORCHIDEE global vegetation model with a process‐based wetland CH4 emission model, calibrated by optimizing its parameters at the site level against representative CH4 flux time series. For boreal bogs north of 50°N, we found that variations in area contributed about 30% to the annual flux. For temperate and tropical wetlands, the variations in area has almost no influence on the annual CH4 emissions but contributes significantly to the seasonal behavior, accounting for 40% and 66% of the seasonal amplitude of fluxes, respectively. In contrast, the interannual variability of wetland area appears to be the dominant cause of interannual variations in regional CH4 emissions from wetlands at all latitudes (largest in the tropics), with up to 90% of annual flux anomalies explained by wetland area anomalies in some years. For example, in 1998, boreal wetlands north of 50°N contributed to approximately 80% of the positive anomaly according to our calculations. We also found that climate anomalies can lead to both increased emitting areas and decreased flux densities at the same time, with opposite effects on the total CH4 flux entering the atmosphere. With a view to forecasting the future trajectory of atmospheric methane content, our results point to the absolute necessity to be able to predict the variations in wetland extent, a hydrological problem, in order to affirm the reliability of simulations of changing methane emissions perturbed by climate.
Tremor bands sweep Cascadia
Authors: Ghosh Abhijit , Vidale John E. , Sweet Justin R. , Creager Kenneth C. , Wech Aaron G. , Houston Heidi
Published: April 2010

During the slow slip events in Cascadia and Japan, a well‐documented feature of nonvolcanic tremor (NVT) is its puzzling slow along‐strike migration. But the cause, possible implications, and underlying physics of this long‐term tremor migration and its relationship with slow slip remain elusive. Here, we use tremor data recorded by a dense seismic array in Cascadia, and apply a beam‐backprojection technique to map the spatiotemporal evolution of tremor with high resolution. It reveals that elongated slip‐parallel bands of tremor activity illuminate the slipping part of the plate interface over the time‐scale of several hours, and sweep Cascadia along‐strike from south to north. We propose that small changes in static stress due to slow slip in a section of the fault cause slip and associated NVT activity in the adjacent section, and the resulting progressive along‐strike transfer of stress is responsible for the long‐term tremor migration during a slow slip event.
Reproducibility of soil moisture ensembles when representing soil parameter uncertainty using a Latin Hypercube–based approach with correlation control
Authors: Flores Alejandro N. , Entekhabi Dara , Bras Rafael L.
Published: April 2010

Representation of model input uncertainty is critical in ensemble‐based data assimilation. Monte Carlo sampling of model inputs produces uncertainty in the hydrologic state through the model dynamics. Small Monte Carlo ensemble sizes are desirable because of model complexity and dimensionality but potentially lead to sampling errors and correspondingly poor representation of probabilistic structure of the hydrologic state. We compare two techniques to sample soil hydraulic and thermal properties (SHTPs): (1) Latin Hypercube (LH) based sampling with correlation control and (2) random sampling from SHTP marginal distributions. A hydrology model is used to project SHTP uncertainty onto the soil moisture state for given forcings. For statistical comparison, we generate 20 ensembles for 7 ensemble sizes. Variance in ensemble moment estimates decreases with increasing ensemble size. The LH‐based approach yields less variance in the estimate of ensemble moments at all ensemble sizes, an advantage greatest with small ensembles. Implications for hydrologic uncertainty assessment, data assimilation, and parameter estimation are discussed.
Equivalence of velocity statistics at constant pressure or constant altitude
Authors: Frehlich R. G. , Sharman R. D.
Published: April 2010

The equivalence of spatial velocity statistics calculated from second‐order structure functions on constant pressure or constant altitude surfaces is demonstrated from analysis of numerical weather prediction model output, rawinsonde data, and commercial aircraft wind measurements. These large data sets allow the development of very accurate statistics. Turbulence scaling laws for horizontal velocity statistics are found to be equivalent for either calculation.
New Cdc2 Tyr 4 phosphorylation by dsRNA‐activated protein kinase triggers Cdc2 polyubiquitination and G2 arrest under genotoxic stresses
Authors: Yoon Cheol‐Hee , Miah Mohammad Alam , Kim Kwang Pyo , Bae Yong‐Soo
Published: April 2010

Cell division cycle 2 (Cdc2) protein is an essential subunit of M‐phase kinase (MPK), which has a key role in G2/M transition. Even though the control of MPK activity has been well established with regard to the phosphorylation of Cdc2 at Thr 14 and/or Tyr 15 and Thr 161, little is known about the proteolytic control of Cdc2. In this study, we observed that Cdc2 was downregulated under genotoxic stresses and that double‐stranded RNA‐activated protein kinase (PKR) was involved in the process. The PKR‐mediated Tyr4 phosphorylation triggered Cdc2 ubiquitination. Phospho‐mimic mutations at the Tyr 4 residue (Y4D or Y4E) caused significant ubiquitination of Cdc2 even in the absence of PKR. Our findings demonstrate that (i) PKR, Ser/Thr kinase, phosphorylates its new substrate Cdc2 at the Tyr 4 residue, (ii) PKR‐mediated Tyr 4‐phosphorylation facilitates Cdc2 ubiquitination and proteosomal degradation, (iii) unphosphorylated Tyr 4 prevents Cdc2 ubiquitination, and (iv) downstream from p53, PKR has a crucial role in G2 arrest and triggers Cdc2 downregulation under genotoxic conditions.
Anticipating the use of life extension technologies
Authors: Lucke Jayne C , Herbert Danielle , Partridge Brad , Hall Wayne D
Published: April 2010

The first effective life extension technologies might well become available within the next few years. Experts from the University of Queensland, Australia, explore the possible public reaction to these therapies and the ethical and social concerns they raise, drawing on the experience of assisted reproduction technologies