bluuebunny/crossref_metadata_2025 huggingface dataset:
Does One Size Fit All? The Suitability of Answer Formats for Different Constructs Measured
Authors: Dolnicar Sara , Grün Bettina
Published: May 2009

Survey research is used to investigate a variety of different constructs, such as beliefs, behavioural intentions, perceptions, preferences and so on. Despite the wide range of constructs studied by social scientists, the ordinal answer format tends to be used across the majority of survey research studies. We challenge this standard approach in survey research by hypothesizing that the ordinal answer format is not optimal under all circumstances. Instead, we propose that the suitability of answer formats depends on the construct measured.

We conduct a repeat measurement study using binary, ordinal and metric answer formats measuring two different constructs: beliefs and behavioural intentions. A clear interaction effect between answer formats and constructs is revealed. This supports the notion that no single answer format is optimal for all research problems, but that some constructs are naturally more suitable for certain answer formats than others. These findings call for increased use of pre-studies to determine the optimal answer format before fieldwork is conducted rather than relying on standard answer formats.
The Development of EERA: Software for Assessing Rheumatic Joint Erosions
Authors: Emond Patrick D. , Choi Abram , O'Neill John , Xie Jason , Adachi Rick , Gordon Chris L.
Published: May 2009

Objective

The principal aim of this study was to create a segmentation program, to be used by nonmusculoskeletal or junior fellows, that defines the bones in the metacarpophalangeal joint in a dynamic 3-dimensional image that will lead to higher inter-reader agreement of bone erosion scores.

Methods

The second to fifth metacarpal head and phalangeal bases of 15 participants were rated according to the Rheumatoid Arthritis Magnetic Resonance Imaging Scoring system by one trained and one untrained reader. Two comparisons were made. The first comparison was between the 2 readers using only the traditional 2-dimensional magnetic resonance image set. The second comparison was between the 2 readers, with the untrained reader using a custom segmentation program with traditional 2-dimensional magnetic resonance image set.

Results

The software marginally increased inter-reader reliability with the exception of the second metacarpal head, for which reliability was increased substantially. Future work will concentrate on improving image acquisition, better delineate erosions from surrounding bone oedema, and address methods to directly determine erosion volumes.

Conclusions

Software designed to display dynamic 3-dimensional images enables a relatively untrained user to score the metacarpophalangeal joints in the hand for erosions equivalent to that produced by an expert using the manual methods.
Colour Doppler Ultrasound Assessment of the Normal Neonatal Hip
Authors: Ortiz-Neira Clara L. , Laffan Eoghan , Daneman Alan , Fong Katherine , Roposch Andreas , Ohlsson Arne , Jarrin Jose , Wang Chenghua , Wedge John , Doria Andrea S.
Published: May 2009

Objective

To determine the morphology and hemodynamic characteristics of the arterial vessels of the proximal femur according to specific anatomic regions in asymptomatic neonates in 2 pediatric-based health care institutions.

Methods

Forty-three neonates (29 female, 14 male; age range, 2 d–3 mo; median age, 3 d) were enrolled in the study. Thirty-two (37%) of 86 hips were classified as Graf type IIA joints (mean alpha angle, 56.0° ± 2.7°), and 54 (63%) were classified as type I joints (mean alpha angle, 65.0° ± 4.6°).

Results

Colour and spectral Doppler imaging identified vessels running along the acetabular labrum, epiphyseal vessels, and femoral neck. We showed 4 different patterns of vascularity of the hips: radial, parallel, mixed radial–parallel, and indeterminate, however, they were not related to the hip maturity ( P = .3, coronal plane; P = .62, transverse plane) or to the amount of colour pixels identified in each region ( P = .35). The mean number of pixels in the ligamentum teres region was significantly higher than that in other regions of interest ( P = .03). Except for the acetabular labrum arteries, Doppler spectrum waveforms of proximal femur arteries presented with low resistivity. There was a tendency towards females' acetabular arteries presenting with lower peak systolic velocities than males' acetabular arteries ( P = .06).

Conclusions

Colour Doppler spectrum waveforms and intensity of vascularity in normal neonatal hips differ according to the anatomic region under evaluation. This observation deserves further investigation on its role on the physiopathogenesis of neonatal hip disorders.
Inhibition of hepatic damage and liver fibrosis by brain natriuretic peptide
Authors: Sonoyama Takuhiro , Tamura Naohisa , Miyashita Kazutoshi , Park Kwijun , Oyamada Naofumi , Taura Daisuke , Inuzuka Megumi , Fukunaga Yasutomo , Sone Masakatsu , Nakao Kazuwa
Published: May 2009

Anti‐fibrotic and organ protective effects of brain natriuretic peptide (BNP) have been reported. In this study, effects of BNP on liver fibrosis were examined in the carbon tetrachloride (CCl4)‐induced liver fibrosis model using BNP‐transgenic (Tg) and wild‐type (WT) mice. Twice‐a‐week intraperitoneal injections of CCl4 for 8 weeks resulted in massive liver fibrosis, augmented transforming growth factor (TGF)‐β1 and type I procollagen α1 chain (Col1a1) mRNA expression, and the hepatic stellate cell (HSC) activation in WT mice, all of which were significantly suppressed in Tg mice. These observations indicate that BNP inhibits liver fibrosis by attenuating the activation of HSCs.
Identification of the nucleophilic factors and the productive complex for the editing reaction by leucyl‐tRNA synthetase
Authors: Hagiwara Yohsuke , Nureki Osamu , Tateno Masaru
Published: May 2009

To ensure fidelity of translation, several aminoacyl‐tRNA synthetases (aaRSs) possess editing capability to hydrolyse mis‐aminoacylated tRNAs. In this report, based on our previously‐modelled structure of leucyl‐tRNA synthetase (LeuRS) complexed with valyl‐tRNALeu, further structural modelling has been performed along with molecular dynamics simulations. This enabled the identification of the nucleophile, which is different from that suggested by the crystal structure of the LeuRS • Nva2AA complex. Our results revealed that the 3′ hydroxyl group of A76 acts as a “gate” to regulate the accessibility of the nucleophile; thus, the opening of the gate leads to the productive complex for the reaction.
Review on early technology assessments of nanotechnologies in oncology
Authors: Retèl Valesca P. , Hummel Marjan J.M. , van Harten Wim H.
Published: May 2009

Nanotechnology is expected to play an increasingly important role in the diagnostics, prognostics, and management of targeted cancer treatments. While papers have described promising results for nanotechnology in experimental settings, the translation of fundamental research into clinical applications has yet to be widely adopted. In future, policy makers will need to anticipate new developments for clinical implementation and introduce technology assessments. Here we present an overview of the literature on the technology assessments that have already been undertaken on early stage nanotechnology in cancer care, with particular emphasis placed on clinical efficacy, efficiency, logistics, patient‐related features and technology dynamics.

Owing to the current stage of development of most nanotechnologies, we found only a limited number of publications describing the application of either Health Technology Assessment (HTA) or Constructive Technology Assessment (CTA). In spite of the promising conclusions of most papers concerning the benefits of clinical implementation, actual clinically relevant applications were rarely encountered, and so far only a few publications report application of systematic forms of technology assessment. Most articles consider aspects of environmental safety, regulation and ethics, often mentioning the need to investigate such issues more thoroughly. Evaluation of financial and organizational aspects is often missing. In order to obtain a realistic perspective on the translation and implementation process there is a need for a broad and systematic evaluation of nanotechnologies at early stages of development. Assessment methods taking technology dynamics into account, such as Constructive Technology Assessment (CTA) should be considered for evaluation purposes.
Nutritional factors in stroke
Authors: Gariballa S. E.
Published: May 2009

Observational studies support the role of modifying lifestyle-related risk factors such as diet, physical activity and alcohol use in stroke prevention. For example, increased Na intake is associated with hypertension, and reduction in salt consumption may significantly lower blood pressure and may reduce stroke mortality. Moderately elevated homocysteine levels may be associated with stroke and are associated with deficiency of dietary intake of folate, vitamin B6and vitamin B12. Consumption of a diet rich in fruits, vegetables, folate, K, Ca, Mg, dietary fibre, fish and milk may protect against stroke. Regular physical activity may also protect against stroke through its role in controlling various risk factors such as hypertension, diabetes mellitus and obesity. The role of fat intake as a risk factor for stroke remains uncertain, whereas the association between stroke and cholesterol has more convincingly been demonstrated by the recent intervention trials using statins. There is also evidence that a low serum albumin may be causally linked to stroke risk and outcome and that a significant number of stroke patients are undernourished on admission and their nutritional status deteriorates further whilst in hospital. Undernutrition is associated with increasing morbidity and mortality and nutritional supplements may have some beneficial effect on some outcome measures.
RESPONSE OF MAIZE TO PHOSPHORUS FROM FERTILIZER AND CHICKEN MANURE IN A SEMI-ARID ENVIRONMENT OF SOUTH AFRICA
Authors: MATERECHERA S. A. , MORUTSE H. M.
Published: May 2009

Chicken manure is a potential source of plant available phosphorous (P) and this field study explored its use for dry land maize production in a soil with very low inherent P levels. The treatments consisted of applying 0, 20, 40 and 80 kg P ha−1each from chicken manure (2.3% P), inorganic fertilizer (single super phosphate, 10.5% P) and a combination of manure and fertilizer. The treatments were replicated four times in a randomized complete block design over two crop seasons. The results revealed that maize growth and yield responded to the P from both manure and fertilizer compared to the control. There were significantly (p< 0.05) taller plants and yield (grain and biomass) in maize supplied with P than control. At each level of P application however, the response was higher for fertilizer than manure. The combination of manure and inorganic fertilizer produced results that were in the middle. There were strong indications that application of chicken manure was associated with increased lodging possibly due to the additional N in the manure, attack by stalk borer (Buseola fusca) and reduced seedling emergence. The application of chicken manure on the other hand led to increased pH and greater residual P content of the soil than fertilizer. It is concluded that chicken manure presents a viable option for supplying P to sustain maize crops in the smallholder farming sector of South Africa and its management warrants further investigation in view of the potential adverse impacts on soil and water resources that can accrue when large amounts are used for a long period.
THE WATER RELATIONS AND IRRIGATION REQUIREMENTS OF BANANA (MUSA SPP.)
Authors: CARR M. K. V.
Published: May 2009

The results of research on the water relations and irrigation need of banana are collated and summarised in an attempt to link fundamental studies on crop physiology to irrigation practices. Background information on the ecology of the banana and crop development processes, with emphasis on root growth and water uptake, is presented, followed by reviews of the influence of water stress on gas exchange (stomatal conductance, photosynthesis and transpiration), crop water use, and yield. Emphasis is placed on research that has international relevance and, where appropriate, three geographical areas (the tropics, subtropics and Mediterranean climates) are considered. Although roots can extend to depths of 1.0–1.5 m, the ‘effective’ depth of rooting is usually taken to be 0–0.40 m, sometimes extending to 0.60 m. Stomatal conductance is a sensitive measure of soil water availability and plant water status, whilst transpiration rates can be limited by dry air (saturation deficits >2.0 kPa). In the subtropics, there are seasonal differences in the crop coefficient (Kc) with values ranging from 0.6 in the winter months to about 1.0 Epan in the summer. It is difficult to draw generic conclusions with wide applicability from the irrigation experiments as they were reported. All the components of marketable yield can be enhanced by irrigation whilst applying insufficient water delays crop development. Annual yield responses to irrigation are variable, but water use efficiencies of 40 kg ha−1mm−1(fresh fruit/water applied) have been achieved in the tropics and subtropics (and elsewhere up to 80 kg ha−1mm−1with ‘partial’ replacement of the soil water deficit). To ensure large yields of (marketable) fruit, soil water deficits must be kept low (Ψm > −20 kPa at 0.2 m depth). In the subtropics, this means irrigation intervals should not exceed 2–3 d during the summer. The cooling effect of irrigation with micro-sprinklers on the soil and pseudostem temperatures, compared with drippers, can delay crop development and reduce annual yields by 30%. There is some (limited) evidence that the presence of the B genome contributes to drought tolerance. Yield response factors to irrigation for different growth stages have yet to be confirmed. Opportunities to improve the water productivity of the many, diverse banana cultivars need to be explored further.
Animal- and plant-food-based diets and iron status: benefits and costs
Authors: Hambræus Leif
Published: May 2009

Fe seems to be the only nutrient deficiency that industrialized and low-income countries have in common. Thus, Fe is one of the most critical nutrition requirements to be met in most diets in human subjects. Fe deficiency is caused not only by too low an intake, but is also the result of low bioavailability, as well as an increased Fe requirement due to physiological variables or clinical problems which are not met by an increased dietary intake of Fe. In low-income countries poor dietary quality rather than Fe intake seems to be the key determinant of impaired Fe status. Sometimes the Fe intake even exceeds that in populations of industrialized countries. The interaction of all enhancers (e.g. ascorbic acid and meat), as well as inhibitors (such as bran, polyphenols, egg yolk, soyabean products, Ca, Ca3(PO4)2 and phytic acid (or phytate)) is what determines the bioavailability of non-haem-Fe in the meal. Dietary composition seems to be particularly important when Fe reserves are low, or in the presence of Fe deficiency. Furthermore, the development of anaemia as a result of Fe deficiency, secondary to Fe-stress situations, is dependent on the Fe balance in the host. With respect to the dietary intake of Fe, other products in the food consumed as well as previous treatment of the product (e.g. heat treatment and processing) may also influence bioavailability. Despite all efforts to counteract Fe deficiency it still represents one of the dominant problems in the micronutrient sphere. It is apparent that there is no simple solution to the problem, and the fact that Fe deficiency still occurs in affluent societies consuming a mixed diet speaks for itself; a more holistic view of total dietary composition and the role of enhancers and inhibitors is needed.
Ironies of State Building: A Comparative Perspective on the American State
Authors: King Desmond , Lieberman Robert C.
Published: May 2009

This review of new directions in the American and comparative literatures on the state reveals important intellectual trends that parallel each other quite closely. Both comparativists and Americanists address similar questions about the sources of state authority, and both propose similar answers. Collectively, these scholars and others are retheorizing the state—developing a suppler, multidimensional picture of the state's origins, structure, and consequences—to shed light on the reasons for the state's stubborn refusal to cede the stage. The emerging understanding of the state that the authors describe provides a framework not only for revisiting the state in the international realm but also, in dialogue with recent Americanist studies, for revising and deepening the understanding of the state's paradoxical role in American political development and finally setting aside the assumption of the United States as stateless. In this emerging view, American state building, strength, and institutional capacity form through links with society, not necessarily through autonomy from society. But such distinctive patterns provide insights for comparative studies, too, for instance, in respect to the relationship between the state and welfare policy across nations.
Social Policy Digest Online
Authors: Bennett Fran , Jones Ken
Published: May 2009

The Social Policy Digest went online in 2002, and since then has developed into a major web-based resource on UK social policy issues. By the end of 2008 it contained over 22,000 entries, covering policy developments and research findings across the whole range of social policy fields.
The uncertain reasoner: Bayes, logic, and rationality
Authors: Oaksford Mike , Chater Nick
Published: May 2009

Human cognition requires coping with a complex and uncertain world. This suggests that dealing with uncertainty may be the central challenge for human reasoning. InBayesian Rationalitywe argue that probability theory, the calculus of uncertainty, is the right framework in which to understand everyday reasoning. We also argue that probability theory explains behavior, even on experimental tasks that have been designed to probe people's logical reasoning abilities. Most commentators agree on the centrality of uncertainty; some suggest that there is a residual role for logic in understanding reasoning; and others put forward alternative formalisms for uncertain reasoning, or raise specific technical, methodological, or empirical challenges. In responding to these points, we aim to clarify the scope and limits of probability and logic in cognitive science; explore the meaning of the “rational” explanation of cognition; and re-evaluate the empirical case for Bayesian rationality.
The singularity spectrum of the inverse of cookie-cutters
Authors: BARRAL JULIEN , SEURET STÉPHANE
Published: May 2009

Gibbs measures μ on cookie-cutter sets are the archetype of multifractal measures on Cantor sets. We compute the singularity spectrum of the inverse measure of μ. Such a measure is discrete (it is constituted only by Dirac masses), it satisfies a multifractal formalism and its Lq-spectrum possesses one point of non-differentiability. The results rely on heterogeneous ubiquity theorems.
Invariant measures on the space of horofunctions of a word hyperbolic group
Authors: BOWEN LEWIS
Published: May 2009

We introduce a natural equivalence relation on the space ℋ0 of horofunctions of a word hyperbolic group that take the value 0 at the identity. We show that there are only finitely many ergodic measures that are invariant under this relation. This can be viewed as a discrete analog of the Bowen–Marcus theorem. Furthermore, if η is such a measure and G acts on a probability space (X,μ) by measure-preserving transformations then η×μ is virtually ergodic with respect to a natural equivalence relation on ℋ0×X. This is comparable to a special case of the Howe–Moore theorem. These results are applied to prove a new ergodic theorem for spherical averages in the case of a word hyperbolic group acting on a finite space.
Experimenting with a computer essay-scoring program based on ESL student writing scripts
Authors: Coniam David
Published: May 2009

This paper describes a study of the computer essay-scoring program BETSY. While the use of computers in rating written scripts has been criticised in some quarters for lacking transparency or lack of fit with how human raters rate written scripts, a number of essay rating programs are available commercially, many of which claim to offer comparable reliability with human raters. Much of the validation of such programs has focused on native-speaking tertiary-level students writing in subject content areas. Instead of content areas with native-speakers, the data for this study is drawn from a representative sample of scripts from an English as a second language (ESL) Year 11 public examination in Hong Kong. The scripts (900 in total) are taken from a writing test consisting of three topics (300 scripts per topic), each representing a different genre. Results in the study show good correlations between human raters’ scores and the program BETSY. A rater discrepancy rate, where scripts need to be re-marked because of disagreement between two raters, emerged at levels broadly comparable with those derived from discrepancies between paired human raters. Little difference was apparent in the ratings of test takers on the three genres. The paper concludes that while computer essay-scoring programs may appear to rate inside a ‘black box’ with concomitant lack of transparency, they do have potential to act as a third rater, time-saving assessment tool. And as technology develops and rating becomes more transparent, so will their acceptability.
Multimodal student interaction online: an ecological perspective
Authors: Berglund Therese Örnberg
Published: May 2009

This article describes the influence of tool and task design on student interaction in language learning at a distance. Interaction in a multimodal desktop video conferencing environment, FlashMeeting, is analyzed from an ecological perspective with two main foci: participation rates and conversational feedback strategies. The quantitative analysis of participation rates shows that as far as verbal interaction is concerned, multimodality did not have an equalizing effect in this context, contradicting previous research on multimodal student interaction. Additionally, the qualitative analysis of conversational feedback strategies shows that whereas some multimodal strategies were employed, the students did not manage to fully act upon the communicative affordances of the tool, as the feedback ratio during and after the often long broadcasts was relatively low. These findings are related to task and tool design and the article discusses how design improvements in these areas might result in a more constructive language learning ecology.
Designing oral participation in Second Life – a comparative study of two language proficiency courses
Authors: Deutschmann Mats , Panichi Luisa , Molka-Danielsen Judith
Published: May 2009

The following paper presents two stages of an action research project involving two oral proficiency courses held in the virtual world Second Life. Course 1 was conducted during the Autumn of 2007. Based on the experiences of this course, we redesigned many aspects of it in order to improve student activity in terms of oral participation and gave the course again in Spring 2008. By analysing the recordings of four 90-minute sessions, two from each course, we were able to measure student participation based on floor space, turn lengths and turn-taking patterns, and in the study we discuss how different changes in design may have contributed to more favourable outcomes. Results seem to indicate that meaning focussed task design, which involves authenticity and collaborative elements, has a direct impact on learner participation and engagement. Furthermore, our results seem to suggest that technical and social initiations into a complex environment such as SL are important factors that have to be worked into the course design.
An evaluation of independent learning of the Japanese hiragana system using an interactive CD
Authors: Geraghty Barbara , Marcus Quinn Ann
Published: May 2009

As Japanese uses three writing systems (hiragana, katakana, and the ideograms known as kanji), and as materials in the target language include all three, it is a major challenge to learn to read and write quickly. This paper focuses on interactive multi-media methods of teaching Japanese reading which foster learner autonomy.

As little has been published on interactive multi-media methods of teaching Japanese reading, it seems likely that traditional resources are generally used for this activity. The courseware includes sound files showing the pronunciation of eachkanaas well as simultaneous animation showing how to write each character. This paper investigates whether interactive courseware, used independently of classroom interaction, results in measurably greater recognition of the hiragana syllabary than more traditional methods. After briefly situating the study in the context of research on the teaching of Japanese reading and learner autonomy, the paper will present the courseware as well as an empirical study comparing the results of the use of the courseware by learners at beginners’ level: one group using the courseware, and the other using paper-based materials. This is followed by an account of learner diaries written by zero-beginner level learners of Japanese using the courseware.

The study indicates that acquisition of a recognition-level knowledge of hiragana is approximately twice as fast using the courseware as using paper-based materials. Learners also learned to write the hiragana without explicit instruction.
Was wirkt in der Kognitiven Verhaltenstherapie der Panikstörung mit Agoraphobie?
Authors: Lang Thomas , Helbig-Lang Sylvia , Petermann Franz
Published: May 2009

Die kognitive Verhaltenstherapie (KVT) hat sich in empirischen Studien als wirksame Behandlungsform von Panikstörungen mit Agoraphobie erwiesen. Zu den zentralen Behandlungskomponenten gehören a) Psychoedukation über Angst und Panik, b) kognitive Interventionen, um die Tendenz zu Missinterpretationen körperlicher Wahrnehmungen zu vermindern, c) interozeptive und in vivo Exposition sowie d) Bewältigungskompetenzen zur Beeinflussung von körperlichen Symptomen, wie beispielsweise Entspannungs- und Atemtechniken. Empirische Befunde zur Effektivität dieser Interventionen werden vorgestellt und abschließend hinsichtlich ihrer Bedeutung im Rahmen einer evidenzbasierten Therapie der Panikstörung mit und ohne Agoraphobie in der Praxis diskutiert.
Risikofaktor Krankheitsverarbeitung
Authors: Jeske Jana , Bullinger Monika , Plaß Angela , Petermann Franz , Wiegand-Grefe Silke
Published: May 2009

In dieser Arbeit werden Zusammenhänge zwischen dem elterlichen Krankheitsverarbeitungsstil und der gesundheitsbezogenen Lebensqualität von Kindern psychisch kranker Eltern betrachtet. Die elterliche Krankheitsbewältigung wurde mit dem Freiburger Fragebogen zur Krankheitsverarbeitung (FKV), die Lebensqualität der Kinder mit der Elternversion des KINDL-R an 61 Kindern erhoben. Die Lebensqualität der Kinder war aus Sicht der Eltern im Gesamturteil und in den Dimensionen «Psychisches Wohlbefinden», «Freunde» und «Familie» signifikant geringer als die Lebensqualität der Allgemeinbevölkerung. Zum elterlichen Krankheitsbewältigungsstil zeigten sich mittlere signifikante Zusammenhänge. Ein depressiver Verarbeitungsstil war mit einer geringeren kindlichen Lebensqualität assoziiert. Die Ergebnisse belegen die Bedeutung der Krankheitsbewältigung einer elterlichen psychischen Erkrankung für die gesundheitsbezogene Lebensqualität der Kinder.
Does Imitation Benefit Cue Order Learning?
Authors: Garcia-Retamero Rocio , Takezawa Masanori , Gigerenzer Gerd
Published: May 2009

Inferences are often based on uncertain cues, and the accuracy of such inferences depends on the order in which the cues are searched. Previous research has shown that people and computers progress only slowly in individual learning of cue orderings through feedback. A clue to how people (as opposed to computers) solve this problem is social learning: By exchanging information with others, people can learn which cues are relevant and the order in which they should be considered. By means of simulation, we demonstrate that imitate-the-best and imitate-the-majority speed up individual learning, whereas a third social rule, the Borda rule, does not. Imitate-the-best also leads to a steep increase in learning after a single social exchange, to cue orders that are more accurate than ecological validity, and to faster learning than when individuals gain the learning experience of all other group members but learn without social exchange. In two experiments, we find that people speed up cue learning in a similar way when provided with social information, both when they obtain the information from the experimenter or in free discussions with others.
The Sorting Paired Features Task
Authors: Bar-Anan Yoav , Nosek Brian A. , Vianello Michelangelo
Published: May 2009

The sorting paired features (SPF) task measures four associations in a single response block. Using four response options (e.g., good-Republicans, bad-Republicans, good-Democrats, and bad-Democrats), each trial requires participants to categorize two stimuli at once to a category pair (e.g., wonderful-Clinton to good-Democrats). Unlike other association measures, the SPF requires simultaneous categorization of both components of the association in the same trial. Providing measurement flexibility, it is sensitive to both focal, attended concepts and nonfocal, unattended stimulus features (e.g., gender of individuals in a politics SPF). Three studies measure race, gender, and political evaluations, differentiate automatic evaluations between known groups, provide evidence of convergent and discriminant validity with other attitude measures, and illustrate the SPF’s unique measurement qualities.
Origins of the Sample-Size Effect in Explicit Evaluative Judgment
Authors: Kaufmann Martina , Betsch Tilmann
Published: May 2009

This research considers situations in which individuals explicitly form attitude judgments toward a target object after considering a sample of information. Previous research shows sample-size effects under such conditions: Increasing sample size can produce more extreme judgments. Commonly, these effects are attributed to summative processes in information integration. Alternatively, this research proposes that sample size affects perceived reliability of information, which in turn affects the extremity of the subsequent judgment. Three experiments were conducted to empirically substantiate this alternative account. Experiment 1 provides evidence that participants perceive larger samples as more reliable than smaller samples. Experiment 2 demonstrates that perceived reliability mediates the sample-size effect on judgments. Experiment 3 shows that other variables, such as variability, which lowers the perceived reliability, attenuate sample-size effects. The results are explained with reference to the value account model of attitude formation, stating that implicit and explicit modes of attitude formation are guided by different principles of information integration.
An evaluation of ice formation in large‐eddy simulations of supercooled Arctic stratocumulus using ground‐based lidar and cloud radar
Authors: van Diedenhoven B. , Fridlind A. M. , Ackerman A. S. , Eloranta E. W. , McFarquhar G. M.
Published: May 2009

In order to evaluate possible ice formation processes in mixed phase Arctic stratocumulus, we compare measurements of radar reflectivity and Doppler velocity and lidar backscatter coefficient and circular depolarization ratio with the corresponding quantities computed from large‐eddy simulations (LES). The measurements are taken from the Millimeter Cloud Radar and the Arctic High Spectral Resolution Lidar during the Mixed‐Phase Arctic Cloud Experiment in October 2004. Lidar depolarization, computed from LES results including well‐known ice formation and multiplication processes and measured ambient ice nuclei (IN), is near 0%, indicating negligible ice formation, whereas measured median depolarization is 84%, indicating strong ice formation, consistent with in situ aircraft measurements. Reducing ice particle fall speeds, increasing IN concentrations, or introducing a surface source of IN does not sufficiently increase the simulated depolarization values and/or results in poor agreement of other simulated parameters with the measurements. Introducing additional hypothetical ice formation processes (i.e., formation of IN from evaporating drops, freezing of evaporation drops, or droplet freezing rates per unit surface or volume) generally brings all investigated parameters into relatively close agreement with the radar and lidar measurements. These results provide additional evidence for the existence of one or more unestablished ice formation processes in Arctic stratocumulus.
Wintertime water vapor in the polar upper mesosphere and lower thermosphere: First satellite observations by Odin submillimeter radiometer
Authors: Lossow S. , Urban J. , Schmidt H. , Marsh D. R. , Gumbel J. , Eriksson P. , Murtagh D.
Published: May 2009

In this paper we present Odin submillimeter radiometer (Odin/SMR) water vapor measurements in the upper mesosphere and lower thermosphere with focus on the polar latitudes in winter. Measurements since 2003 have been compiled to provide a first overview of the water vapor distribution in this altitude range. Our observations show a distinct seasonal increase of the water vapor concentration during winter at a given altitude above 90 km. Above 95 km the observations exhibit the annual water vapor maximum during wintertime. Model simulations from the Hamburg Model of the Neutral and Ionized Atmosphere (HAMMONIA) and the Whole Atmosphere Community Climate Model version 3 (WACCM3) show results that are very similar to the observations. We suggest that the observed increase in water vapor during winter is mainly caused by a combination of upwelling of moister air from lower altitudes and diffusion processes. Distinct interhemispheric differences in the winter water vapor distribution in the upper mesosphere and lower thermosphere can be observed, both in the observations and the model results. The seasonal water vapor increase in the polar regions is much more pronounced in the Southern Hemisphere winter where higher concentrations can be observed. This observation is most likely due to interhemispheric differences in the underlying dynamics and diffusion processes.
Ecohydrology of groundwater‐dependent ecosystems: 2. Stochastic soil moisture dynamics
Authors: Tamea Stefania , Laio Francesco , Ridolfi Luca , D'Odorico Paolo , Rodriguez‐Iturbe Ignacio
Published: May 2009

In groundwater‐dependent ecosystems, interactions between rainfall, water table fluctuations, and vegetation are exerted through the soil water content. The dynamics of soil moisture, in fact, are strongly coupled to fluctuations of the water table and, together, they control the overall ecosystem dynamics. We propose here a simple process‐based stochastic model for the study of soil moisture dynamics at a generic depth, to complement the stochastic model of water table depth presented in the companion paper. The model presented here is based on a local and depth‐dependent water balance driven by stochastic rainfall (marked Poisson noise) and accounting for processes such as rainfall infiltration, root water uptake, and capillary rise. We obtain a semianalytical formulation of the stationary probability distribution of soil water content at different depths, which is studied for different values of soil, climate, and vegetation parameters. The probability distributions are used to investigate the ecohydrology of groundwater‐dependent ecosystems, including the quantitative description of the vegetation–water table–soil moisture interplay and the probabilistic analysis of root water uptake.
Observation of cyclone‐induced inertial sea‐ice oscillation in Fram Strait
Authors: Lammert A. , Brümmer B. , Kaleschke L.
Published: May 2009

In March 2007 the field campaign FRAMZY took place in the region between Spitsbergen and Greenland. One goal of the experiment was the observation of cyclone impact on ice drift by means of autonomous meteorological buoys, deployed on sea ice. On 23 March an intense cyclone, of about 500 km diameter, passed with about 20 m/s from south to north over the ice‐covered part of the Fram Strait and induced strong inertial oscillations of the sea ice. Ice‐drift velocity fluctuations abruptly increased by a factor of three to values of more than 1 m/s. This was caused by a resonant wind forcing for almost three quarters of the inertial oscillation. Depending on the local ice conditions the oscillations lasted over a two to five days period. The inertial oscillations caused ice drift divergence fluctuations of ±6 · 10−6s−1 and a reduction of ice concentration by up to 11%.
The slow:fast substitution ratio reveals changing patterns of natural selection in γ-proteobacterial genomes
Authors: Shapiro B Jesse , Alm Eric
Published: May 2009

Different microbial species are thought to occupy distinct ecological niches, subjecting each species to unique selective constraints, which may leave a recognizable signal in their genomes. Thus, it may be possible to extract insight into the genetic basis of ecological differences among lineages by identifying unusual patterns of substitutions in orthologous gene or protein sequences. We used the ratio of substitutions in slow- versus fast-evolving sites (nucleotides in DNA, or amino acids in protein sequence) to quantify deviations from the typical pattern of selective constraint observed across bacterial lineages. We propose that elevated S:F in one branch (an excess of slow-site substitutions) can indicate a functionally relevant change, due to either positive selection or relaxed evolutionary constraint. In a genome-wide comparative study of γ-proteobacterial proteins, we find that cell-surface proteins involved with motility and secretion functions often have high S:F ratios, whereas information-processing genes do not. Change in evolutionary constraints in some species is evidenced by increased S:F ratios within functionally related sets of genes (for example, energy production in Pseudomonas fluorescens), whereas other species apparently evolve mostly by drift (for example, uniformly elevated S:F across most genes in Buchnera spp.). Overall, S:F reveals several species-specific, protein-level changes with potential functional/ecological importance. As microbial genome projects yield more species-rich gene trees, the S:F ratio will become an increasingly powerful tool for uncovering functional genetic differences among species.
Carbon and nitrogen substrate utilization in the marine bacterium Sphingopyxis alaskensis strain RB2256
Authors: Williams Timothy J , Ertan Haluk , Ting Lily , Cavicchioli Ricardo
Published: May 2009

Sphingopyxis alaskensis is a marine member of the Alphaproteobacteria that is adapted to heterotrophic growth under nutrient-depleted (oligotrophic) conditions. S. alaskensis strain RB2256 is an ultramicrobacterium (cell volume <0.1 μm3), and has a genome size larger than that of the ultramicrobacterium ‘Candidatus Pelagibacter ubique’ HTCC1062 (SAR11 clade of Alphaproteobacteria): 3.35 versus 1.31 Mbp. In this study, we investigate the carbon and nitrogen metabolism of strain RB2256 using an integrated approach that combines growth and enzyme assays, proteomics and genome analysis. S. alaskensis is able to use specific amino acids and putrescine as a sole carbon and nitrogen source, and higher energy-yielding substrates such as glucose and trehalose as carbon sources. Alanine, in particular, emerges as a very important substrate in S. alaskensis metabolism. In an oligotrophic environment where competition for nutrients is intense, our data support a simplified metabolism for S. alaskensis in which the fate of certain substrates is constrained, especially at the intersections of central carbon and nitrogen metabolism, in order to ensure optimal disposition of scarce resources. This is the first investigation of central metabolism for an oligotrophic ultramicrobacterium that possesses a relatively large genome size. In contrast to the behavior so far observed for SAR11 oligotrophic bacteria, S. alaskensis shows a physiological capacity to exploit increases in ambient nutrient availability and thereby achieve high-population densities.
Weight Loss, HbA1c Reduction, and Tolerability of Cetilistat in a Randomized, Placebo‐controlled Phase 2 Trial in Obese Diabetics: Comparison With Orlistat (Xenical)
Authors: Kopelman Peter , de Groot H. Gerrit , Rissanen Aila , Rossner Stephan , Toubro Soren , Palmer Richard , Hallam Rob , Bryson Andrew , Hickling Roger I.
Published: May 2009

The objective of this multicenter, randomized, double‐blind study was to determine the efficacy and safety of cetilistat and orlistat relative to placebo in obese patients with type 2 diabetes, on metformin. Following a 2‐week run‐in, patients were randomized to placebo, cetilistat (40, 80, or 120 mg three times daily), or orlistat 120 mg t.i.d., for 12 weeks. The primary endpoint was absolute change in body weight from baseline. Secondary endpoints included other measures of obesity and glycemic control. Similar reductions in body weight were observed in patients receiving cetilistat 80 or 120 mg t.i.d. or 120 mg t.i.d. orlistat; these reductions were significant vs. placebo (3.85 kg, P = 0.01; 4.32 kg, P = 0.0002; 3.78 kg, P = 0.008). In the 40 mg t.i.d. and placebo groups, reductions were 2.94 kg, P = 0.958 and 2.86 kg, respectively. Statistically significant reductions in glycosylated hemoglobin (HbA1c) were noted. Cetilistat was well tolerated, and showed fewer discontinuations due to adverse events (AEs) than in the placebo and orlistat groups. Discontinuation in the orlistat group was significantly worse than in the 120 mg cetilistat and placebo groups and was entirely due to gastrointestinal (GI) AEs. Treatment with cetilistat 80 or 120 mg t.i.d., or with orlistat 120 mg t.i.d., significantly reduced body weight and improved glycemic control relative to placebo in obese diabetic patients. Cetilistat was well tolerated with the number of discontinuations due to AEs being similar to placebo.
Quantifying the Space-Efficiency of 2D Graphical Representations of Trees
Authors: McGuffin Michael J , Robert Jean-Marc
Published: May 2009

A mathematical evaluation and comparison of the space-efficiency of various 2D graphical representations of tree structures is presented. As part of the evaluation, a novel metric called the mean area exponent is introduced that quantifies the distribution of area across nodes in a tree representation, and that can be applied to a broad range of different representations of trees. Several representations are analyzed and compared by calculating their mean area exponent as well as the area they allocate to nodes and labels. Our analysis inspires a set of design guidelines as well as a few novel tree representations that are also presented.
Radiolarians decreased silicification as an evolutionary response to reduced Cenozoic ocean silica availability
Authors: Lazarus David B. , Kotrc Benjamin , Wulf Gerwin , Schmidt Daniela N.
Published: May 2009

It has been hypothesized that increased water column stratification has been an abiotic “universal driver” affecting average cell size in Cenozoic marine plankton. Gradually decreasing Cenozoic radiolarian shell weight, by contrast, suggests that competition for dissolved silica, a shared nutrient, resulted in biologic coevolution between radiolaria and marine diatoms, which expanded dramatically in the Cenozoic. We present data on the 2 components of shell weight change—size and silicification—of Cenozoic radiolarians. In low latitudes, increasing Cenozoic export of silica to deep waters by diatoms and decreasing nutrient upwelling from increased water column stratification have created modern silica-poor surface waters. Here, radiolarian silicification decreases significantly (r= 0.91,P< 0.001), from ≈0.18 (shell volume fraction) in the basal Cenozoic to modern values of ≈0.06. A third of the total change occurred rapidly at 35 Ma, in correlation to major increases in water column stratification and abundance of diatoms. In high southern latitudes, Southern Ocean circulation, present since the late Eocene, maintains significant surface water silica availability. Here, radiolarian silicification decreased insignificantly (r= 0.58,P= 0.1), from ≈0.13 at 35 Ma to 0.11 today. Trends in shell size in both time series are statistically insignificant and are not correlated with each other. We conclude that there is no universal driver changing cell size in Cenozoic marine plankton. Furthermore, biologic and physical factors have, in concert, by reducing silica availability in surface waters, forced macroevolutionary changes in Cenozoic low-latitude radiolarians.
Solution structure of eggcase silk protein and its implications for silk fiber formation
Authors: Lin Zhi , Huang Weidong , Zhang Jingfeng , Fan Jing-Song , Yang Daiwen
Published: May 2009

Spider silks are renowned for their excellent mechanical properties and biomimetic and industrial potentials. They are formed from the natural refolding of water-soluble fibroins with α-helical and random coil structures in silk glands into insoluble fibers with mainly β-structures. The structures of the fibroins at atomic resolution and silk formation mechanism remain largely unknown. Here, we report the 3D structures of individual domains of a ≈366-kDa eggcase silk protein that consists of 20 identical type 1 repetitive domains, one type 2 repetitive domain, and conserved nonrepetitive N- and C-terminal domains. The structures of the individual domains in solution were determined by using NMR techniques. The domain interactions were investigated by NMR and dynamic light-scattering techniques. The formation of micelles and macroscopic fibers from the domains was examined by electron microscopy. We find that either of the terminal domains covalently linked with at least one repetitive domain spontaneously forms micelle-like structures and can be further transformed into fibers at ≥37 °C and a protein concentration of >0.1 wt%. Our biophysical and biochemical experiments indicate that the less hydrophilic terminal domains initiate the assembly of the proteins and form the outer layer of the micelles whereas the more hydrophilic repetitive domains are embedded inside to ensure the formation of the micelle-like structures that are the essential intermediates in silk formation. Our results establish the roles of individual silk protein domains in fiber formation and provide the basis for designing miniature fibroins for producing artificial silks.