bluuebunny/crossref_metadata_2025 huggingface dataset:
The Role of Culture in Public Goods and Other Experiments
Authors: Chai Sun-Ki , Dorj Dolgorsuren , Hampton Kyle , Liu Ming
Published: October 2011

Burgeoning literature within the social sciences studies the effects of culture on collective action. In economics, this topic can be found in the rising fields of behavioral economics (Camerer, Loewenstein, and Rabin 2004; Diamond, Vartiainen, and Jahnssonin 2007; Thaler 2007; Wilkinson 2007) and experimental economics (Friedman and Sunder 1994; Friedman 2004; Kagel and Roth 1995), where increasing notice is taken of individuals who do not behave uniformly as self-interested, rational utility maximizers. Instead, altruism (Andreoni and Miller 2008), reciprocity (Fehr and Gachter 2000; Fischbacher and Gachter 2010; Rabin 1993), social welfare maximization (Charness and Rabin 2002), and inequality aversion (Bolton and Ockenfels 2000; Fehr and Schmidt 1999) have been proposed as explanations for behavior in collective action situations.
Privacy Protection in Social Science Research: Possibilities and Impossibilities
Authors: Albright Jeremy J.
Published: October 2011

The ubiquity of data in the twenty-first century provides unprecedented opportunities for social science research, but it also creates troubling possibilities for privacy violations. The emerging field of statistical disclosure control (SDC) studies how data collectors and analysts can find an optimal solution to balancing privacy protection and data utility. This article introduces SDC to readers in the applied political science research community and outlines its implications for analyzing individual-level data. The vocabulary of SDC is introduced and is followed with a discussion emphasizing just how easy it is to break almost any release of supposedly “anonymized” data. The article then describes how SDC measures almost always destroy the ability of researchers to accurately analyze complex survey data. These results are in conflict with increasing trends toward greater transparency in the social sciences. A discussion of the future of SDC concludes the article.
Context, Behavior, Outcomes, and Tradeoffs: The Intellectual Contributions of G. Bingham Powell, Jr. to the Study of Comparative Democratic Processes
Authors: Achen Christopher H. , Dalton Russell J. , Huber John , Kedar Orit , Shively W. Phillips , Strøm Kaare
Published: October 2011

G Bingham Powell's core intellectual contribution to the study of politics has been to help us understand fundamental normative tradeoffs that are inherent to institutional choice in democratic political systems. The tradeoffs involve dimensions of political performance of central concern in the discipline, including political violence, political participation, political representation, political accountability, and political stability. In offering innovative insights about these substantive topics, Powell's research has played a crucial role in shaping the subfield of comparative politics by offering important lessons about how to advance the study of democratic systems.
To what extent do weight gain and eating avidity during infancy predict later adiposity?
Authors: Wright Charlotte M , Cox Katherine Marie , Sherriff Andrea , Franco-Villoria Maria , Pearce Mark S , Adamson Ashley J ,   Gateshead Millennium Study core team
Published: October 2011

Objective

To determine the extent to which weight gain and eating behaviours in infancy predict later adiposity.

Design

Population-based, prospective, longitudinal birth cohort study. Weights collected in infancy were used to calculateZ-scores for weight gain to age 1 year conditional on birth weight (CWG). To avoid multiple significance tests, variables from the parent questionnaire completed at age 1 year describing eating avidity were combined using general linear modelling to create an infancy avidity score. Anthropometry, skinfold thicknesses and bioelectrical impedance data collected at age 7–8 years were combined using factor analysis, to create an adiposity index.

Setting

Gateshead, UK.

Subjects

Members of the Gateshead Millennium Study cohort with data at both time points (n561).

Results

CWG in infancy significantly predicted adiposity at age 7 years, but related more strongly to length and lean mass. High adiposity (> 90th internal percentile) at age 7 years was significantly associated with high CWG (relative risk 2·76; 95 % CI 1·5, 5·1) in infancy, but less so with raised (> 74th internal percentile) eating avidity in infancy (relative risk 1·87; 95 % CI 0·9, 3·7). However, the majority of children with high weight gain (77·6 %) or avidity (85·5 %) in infancy did not go on to have high adiposity at age 7 years.

Conclusions

Rapid weight gain in infancy and the eating behaviours which relate to it do predict later adiposity, but are more strongly predictive of later stature and lean mass.
Dietary patterns are associated with weight gain in newlyweds: findings from a cross-sectional study in Shanghai, China
Authors: Zhang Yifeng , Tan Hui , Dai Xuan , Huang Honger , He Gengsheng
Published: October 2011

Objective

The present study aimed to characterize the dietary patterns of newlyweds married within one year and to examine the factors associated with weight changes.

Design

A cross-sectional study was carried out in 2009.

Setting

Baoshan District, Shanghai, China.

Subjects

A total of 342 pairs of newlyweds were recruited at their first visit. Weight and height were measured and food intake was measured based on an FFQ with forty-nine items. Dietary patterns were identified through factor analysis, and the factors associated with weight changes were determined by multiple regression models.

Results

Average weight gain of the participants during marital transition was 1·9 kg (2·2 kg for men and 1·6 kg for women). Four major dietary patterns were identified: vegetable pattern, sweets and fats pattern, legume pattern and poultry, beef and mutton pattern. In multivariate analyses, the highest quintile of factor 2 (sweets and fats pattern) was significantly associated with weight gain after marriage in a comparison with the lowest quintile (β= 2·94; 95 % CI 0·75, 5·15;P= 0·01) in men. The highest quintile of factor 4 (poultry, beef and mutton pattern) was inversely associated with weight gain after marriage in a comparison with the lowest quintile (β= −1·21; 95 % CI −2·32, −0·11;P= 0·03).

Conclusions

Our results suggest that a pattern rich in sugar, oil and condiments may lead to greater marital weight gain in men; another pattern rich in poultry, beef and mutton may lead to less marital weight gain in both men and women.
Tree-ring dating of meteorite fall in Sikhote-Alin, Eastern Siberia – Russia
Authors: Fantucci R. , Di Martino Mario , Serra Romano
Published: October 2011

This research deals with the fall of the Sikhote-Alin iron meteorite on the morning of 12 February 1947, at about 00:38 h Utrecht, in a remote area in the territory of Primorsky Krai in Eastern Siberia (46°09′36″N, 134°39′22″E). The area engulfed by the meteoritic fall was around 48 km2, with an elliptic form and thousands of craters. Around the large craters the trees were torn out by the roots and laid radially to the craters at a distance of 10–20 m; the more distant trees had broken tops. This research investigated through dendrocronology n.6 Scots pine trees (Pinus Sibirica) close to one of the main impact craters. The analysis of growth anomalies has shown a sudden decrease since 1947 for 4–8 years after the meteoritic impact. Tree growth stress, detected in 1947, was analysed in detail through wood microsection that confirmed the winter season (rest vegetative period) of the event. The growth stress is mainly due to the lost crown (needle lost) and it did not seem to be caused due to direct damages on trunk and branches (missing of resin ducts).
ARROW UPDATE LOGIC
Authors: KOOI BARTELD , RENNE BRYAN
Published: October 2011

We presentArrow Update Logic, a theory of epistemic access elimination that can be used to reason about multi-agent belief change. While the belief-changing “arrow updates” of Arrow Update Logic can be transformed into equivalent belief-changing “action models” from the popular Dynamic Epistemic Logic approach, we prove that arrow updates are sometimes exponentially more succinct than action models. Further, since many examples of belief change are naturally thought of from Arrow Update Logic’s perspective of eliminating access to epistemic possibilities, Arrow Update Logic is a valuable addition to the repertoire of logics of information change. In addition to proving basic results about Arrow Update Logic, we introduce a new notion of common knowledge that generalizes both ordinary common knowledge and the “relativized” common knowledge familiar from the Dynamic Epistemic Logic literature.
Microwave MEMS devices designed for process robustness and operational reliability
Authors: Sterner Mikael , Somjit Nutapong , Shah Umer , Dudorov Sergey , Chicherin Dmitry , Räisänen Antti , Oberhammer Joachim
Published: October 2011

This paper presents an overview on novel microwave micro-electromechanical systems (MEMS) device concepts developed in our research group during the last 5 years, which are specifically designed for addressing some fundamental problems for reliable device operation and robustness to process parameter variation. In contrast to conventional solutions, the presented device concepts are targeted at eliminating their respective failure modes rather than reducing or controlling them. Novel concepts of MEMS phase shifters, tunable microwave surfaces, reconfigurable leaky-wave antennas, multi-stable switches, and tunable capacitors are presented, featuring the following innovative design elements: dielectric-less actuators to overcome dielectric charging; reversing active/passive functions in MEMS switch actuators to improve recovery from contact stiction; symmetrical anti-parallel metallization for full stress-control and temperature compensation of composite dielectric/metal layers for free-standing structures; monocrystalline silicon as structural material for superior mechanical performance; and eliminating thin metallic bridges for high–power handling. This paper summarizes the design, fabrication, and measurement of devices featuring these concepts, enhanced by new characterization data, and discusses them in the context of the conventional MEMS device design.
Slab1.0: A three‐dimensional model of global subduction zone geometries
Authors: Hayes Gavin P. , Wald David J. , Johnson Rebecca L.
Published: October 2011

We describe and present a new model of global subduction zone geometries, called Slab1.0. An extension of previous efforts to constrain the two‐dimensional non‐planar geometry of subduction zones around the focus of large earthquakes, Slab1.0 describes the detailed, non‐planar, three‐dimensional geometry of approximately 85% of subduction zones worldwide. While the model focuses on the detailed form of each slab from their trenches through the seismogenic zone, where it combines data sets from active source and passive seismology, it also continues to the limits of their seismic extent in the upper‐mid mantle, providing a uniform approach to the definition of the entire seismically active slab geometry. Examples are shown for two well‐constrained global locations; models for many other regions are available and can be freely downloaded in several formats from our new Slab1.0 website, http://on.doi.gov/d9ARbS. We describe improvements in our two‐dimensional geometry constraint inversion, including the use of ‘average’ active source seismic data profiles in the shallow trench regions where data are otherwise lacking, derived from the interpolation between other active source seismic data along‐strike in the same subduction zone. We include several analyses of the uncertainty and robustness of our three‐dimensional interpolation methods. In addition, we use the filtered, subduction‐related earthquake data sets compiled to build Slab1.0 in a reassessment of previous analyses of the deep limit of the thrust interface seismogenic zone for all subduction zones included in our global model thus far, concluding that the width of these seismogenic zones is on average 30% larger than previous studies have suggested.
Backwater and river plume controls on scour upstream of river mouths: Implications for fluvio‐deltaic morphodynamics
Authors: Lamb Michael P. , Nittrouer Jeffrey A. , Mohrig David , Shaw John
Published: October 2011

Sediment flux from rivers to oceans is the fundamental driver of fluvio‐deltaic morphodynamics and continental margin sedimentation, yet sediment transport across the river‐to‐marine boundary is poorly understood. Coastal rivers typically are affected by backwater, a zone of spatially decelerating flow that is transitional between normal flow upstream and the offshore river plume. Flow deceleration in the backwater zone, as well as spreading of the offshore plume, should render rivers highly depositional near their mouths, leading to sedimentation and eventual elimination of the backwater zone at steady state. This reasoning is counter to observations of riverbed scour, erosional bed forms, and long‐lived backwater zones near the mouths of some coastal rivers (e.g., Mississippi River, United States). To explain these observations, we present a quasi‐2‐D model of a coupled fluvial backwater and offshore river plume system and apply it to the Mississippi River. Results show that during high‐discharge events the normal‐flow depth can become larger than the water depth at the river mouth resulting in drawdown of the water surface, spatial acceleration of flow, and erosion of the riverbed. As proposed by Lane (1957), the transition to drawdown and erosion is ultimately forced by spreading of the offshore river plume. This points to the need to model coupled river and river plume systems with a dynamic backwater zone under a suite of discharges to accurately capture fluvio‐deltaic morphodynamics and connectivity between fluvial sediment sources and marine depositional sinks.
Radar beam‐ and range‐weighting effects on three‐dimensional radar imaging for the atmosphere
Authors: Chen Jenn‐Shyong , Chen Chun‐Hua , Furumoto Jun‐ichi
Published: October 2011

Multiple‐receiver and multiple‐frequency radar imaging techniques used with VHF atmospheric radar can improve, respectively, angular and range resolutions of the atmospheric irregularity structure inside the radar volume. In addition to the imaging method itself, calibration of the imaging is also crucial to yield a better visualization of the irregularity structure. In this paper, the three‐dimensional radar imaging using multiple receivers and multiple frequencies simultaneously is demonstrated on the basis of numerical simulation with the Capon method. More than previous works did, radar beam and range weighting effects on the imaging were examined in this study. Beam weighting effect on angular brightness distribution of the scattering region is apparent, but it gives different impacts on the range imaging as accompanying with the range weighting effect: the higher the range position of the scattering region is, the smaller the synthetic influence of both weighting effects will be. Beam weighting effect also causes a range‐shortening effect for a localized scattering region, which should be considered in interpreting the shift of range brightness distribution with angular location of the target. Moreover, it is demonstrated that adaptable beam width is effectual to recover a two‐blob structure and a wavy layer. An experimental case was also investigated to demonstrate the need of correcting beam weighting effect using adaptable beam width; meanwhile, it suggests that an adaptable range weighting function could be helpful to a further amendment of the three‐dimensional imaging.
Factors Predicting Individual Variability in Diet‐Induced Weight Loss in MF1 Mice
Authors: Vaanholt Lobke M. , Magee Victoria , Speakman John R.
Published: October 2011

The effectiveness of caloric restriction (CR) as a treatment for obesity varies considerably between individuals. Reasons for this interindividual variation in weight loss in response to CR may lie in pre‐existing individual differences and/or individual differences in compensatory responses. Here we studied the responses of 127 MF1 mice to 30% CR over four weeks, and investigated whether pre‐existing differences or compensatory changes in body temperature, resting metabolic rate (RMR) and behavior explained the variation observed in body mass (BM) and fat mass (FM) changes. Mice showed considerable variation in BM loss (36–1%), and in the type of tissue lost (FM or fat free mass, FFM). About 50% of the variation in BM and FM loss could be predicted by pre‐existing differences in food intake, RMR, and general activity, where BM loss was greater when food intake was lower and activity and RMR were higher. Compensatory changes in activity and body temperature together explained ∼50% of the variation in BM and FM loss in both sexes. In models incorporating baseline variables and compensatory changes, food intake, and activity were the strongest predictors of weight loss in both sexes; i.e., lower baseline food intake and increased changes in activity resulted in greater BM and FM loss. Interestingly, increased baseline activity was a significant predictor of weight loss independent of compensatory changes in activity. Identifying factors involved in individual variability in weight loss may give insights into the mechanisms that underlie this variability, and is important to develop individually tailored weight‐management strategies.
Visceral Fat Area Cutoff for the Detection of Multiple Risk Factors of Metabolic Syndrome in Japanese: The Hitachi Health Study
Authors: Yumi Matsushita , Toru Nakagawa , Shuichiro Yamamoto , Yoshihiko Takahashi , Tetsuji Yokoyama , Tetsuya Mizoue , Mitsuhiko Noda
Published: October 2011

The relationships between metabolic risk factors and abdominal fat distribution determined using computed tomography (CT) are poorly defined in large populations. We investigated the cutoff values of the visceral fat area (VFA) to detect subjects with multiple risk factors of metabolic syndrome (MS) by sex and age groups, and attempted to examine whether sex‐ and age‐specific cutoff values are needed. The subjects of this study were 11,561 Japanese men and women who participated in the Hitachi Health Study, received CT examination, and answered questionnaires on lifestyles between 2004 and 2009. VFA and waist circumference were measured using CT. The VFA cutoff values yielding an 80% sensitivity for the detection of multiple risk factors of MS were typically smaller among men under the age of 40 years (<40 years vs. ≥40 years; 86.4 cm2 vs. 103.9 cm2). The area under the receiver operator characteristic curve of VFA for the detection tended to decrease according to age (P = 0.056 and P = 0.020 for trends in men and women). Age‐ and sex‐specific cutoff values are needed. The sensitivity of the subjects under the age of 40 years is relatively smaller (70.0% for men and 60.0% for women) compare to other age groups when the same cutoff value is used regardless of age (e.g., cutoff value calculated to correspond to 80% sensitivity for subjects of all ages). Therefore, a smaller VFA cutoff point should be used among men under the age of 40 years.
Racial Differences in Measures of Obesity and Risk of Colon Adenoma
Authors: Thompson Cheryl L. , Berger Nathan A. , Chak Amitabh , Li Li
Published: October 2011

Obesity is an established risk factor for several malignancies. However, the specific measurement of obesity most relevant to colon neoplasia is still debated, and evidence has suggested gender and racial differences in this measurement. In this study, we sought to compare which measurement—BMI, waist circumference (WC), waist‐to‐hip ratio (WHR) or waist‐to‐height ratio (WHtR)—is most strongly associated with development of colon adenomas, a precursor of colon cancer, and to investigate differences in this association between racial groups. We confirmed the strong association between WHR, as a measure of central obesity, and development of colon neoplasia. In our overall analysis, patients in the highest WHR quartile showed a substantial increase in risk of colon adenomas compared to patients in the lowest WHR quartile (odds ratio (OR) = 1.82, 95% confidence interval (CI): 1.12–2.71, Ptrend = 0.0017). In stratified analyses, we noted that strongly associated obesity measures in European Americans were WC (OR = 2.38, 95% CI = 1.45–3.92, Ptrend = 0.0004) and BMI (OR = 2.18, 95% CI = 1.37–3.49, Ptrend = 0.0015), whereas in African Americans, WHR was the strongest and the only obesity measure statistically significantly associated with adenoma risk (OR = 2.12, 95% CI = 1.05–4.30, Ptrend = 0.025). Our data highlight the importance of obesity in the development of early colon neoplasia and suggest substantial racial differences in the measures of obesity most strongly associated with risk of colon adenomas.
Fat in Android, Trunk, and Peripheral Regions Varies by Ethnicity and Race in College Aged Women
Authors: Stults‐Kolehmainen Matthew A. , Stanforth Philip R. , Bartholomew John B.
Published: October 2011

The aim of this study was to determine whether quantity of fat is different across the central (i.e., android, trunk) and peripheral (i.e., arm, leg, and gynoid) regions among young African‐American (AA), Asian (AS), Hispanic (HI), and non‐Hispanic white (NHW) women. A cohort of 1,161 women (18–30 years) from university physical activity classes were assessed for body composition via dual‐emission X‐ray absorptiometry (DXA). The mean total body fat percent (TBF%, , range = 11.4–54.4%) indicates sufficient variability for the aims. A linear mixed model (LMM) revealed an ethnicity by region fat% interaction (P < 0.0001). Differences existed between ethnicities for each region fat% (all P's < 0.0001) except between HI and AA for the arm region (P = 0.0086) and between AS and NHW for all peripheral regions (P > 0.05). AAs had the highest fat% and HI had the second highest fat% for each region. AS had the third highest fat% for the trunk and android regions. For each ethnicity, the gynoid region had the greatest fat%, followed by the android region, whereas the arm region had the lowest fat%. Future research needs to determine if ethnic differences in central body fat in young women are associated with health outcomes such as cardiovascular disease and insulin resistance.
Genetic and Environmental Influences on BMI From Late Childhood to Adolescence are Modified by Parental Education
Authors: Lajunen Hanna‐Reetta , Kaprio Jaakko , Rose Richard J. , Pulkkinen Lea , Silventoinen Karri
Published: October 2011

To investigate how parental education modifies genetic and environmental influences on variation in BMI during adolescence, self‐reported BMI at 11–12, 14, and 17 years of age was collected from a population sample of 2,432 complete Finnish twin pairs born in 1983–1987. Based on parental report, twins were divided to those with high (both parents high school graduates), mixed level (one parent a graduate, the other not), and limited (neither parent a graduate) parental education. Genetic and environmental influences on variation in BMI in different education classes were modeled using twin analysis. Heritability of BMI among 11–12‐year‐olds with high parental education was 85–87% whereas it was 61–68% if parental education was limited or mixed level. Common environmental effect, i.e., effect of environmental factors shared by family members, was found (17–22%) if parental education was limited or mixed level but not if it was high. With increasing parental education, common environmental variance in BMI decreased at age 14 among boys (from 22 to 3%) and girls (from 17 to 10%); heritability increased among boys from 63 to 78%, but did not change among girls. The common environmental component disappeared and heritability of BMI was larger at the age of 17 in all parental education classes. To conclude, common environment did not affect variation of adolescent BMI in high‐educated families but did so in families with limited parental education. This suggests that intervention and prevention campaigns could effectively target families identified by limited parental education.
Educational Differences in Obesity in the United States: A Closer Look at the Trends
Authors: Yu Yan
Published: October 2011

Both body weight and educational attainment have risen in the United States. Empirical evidence regarding educational differences in obesity (BMI ≥30) is inconsistent. According to some widely cited claims, these differences have declined since the 1970s, and the most educated have experienced the greatest gain in obesity. Prior research was limited in grouping college graduates with nongraduates, combining men and women in the same analysis, and using self‐reported rather than measured anthropometric information. Using the National Health and Nutrition Examination Surveys (NHANES), we address these issues and examine changing educational differences in obesity from 1971–1980 to 1999–2006 for non‐Hispanic whites and blacks in two separate age groups (25–44 vs. 45–64 years). We find that (i) obesity differentials by education have remained largely stable, (ii) compared with college graduates, less educated whites and younger black women continue to be more likely to be obese, (iii) but the differentials are larger for women than men, and weak or nonexistent among black men and older black women. There are exceptions to the overall trend. The obesity gap has widened between the two groups of college‐educated younger women, but disappeared between the least and most educated younger white men. Thus, the increase in obesity was similar for most educational groups, but significantly greater for younger women with some college and smaller for younger white men without a high‐school degree. Lumping together the two distinct college groups has biased previous estimates of educational differences in obesity.
Identification of persulfide-binding and disulfide-forming cysteine residues in the NifS-like domain of the molybdenum cofactor sulfurase ABA3 by cysteine-scanning mutagenesis
Authors: Lehrke Markus , Rump Steffen , Heidenreich Torsten , Wissing Josef , Mendel Ralf R. , Bittner Florian
Published: October 2011

The Moco (molybdenum cofactor) sulfurase ABA3 from Arabidopsis thaliana catalyses the sulfuration of the Moco of aldehyde oxidase and xanthine oxidoreductase, which represents the final activation step of these enzymes. ABA3 consists of an N-terminal NifS-like domain that exhibits L-cysteine desulfurase activity and a C-terminal domain that binds sulfurated Moco. The strictly conserved Cys430 in the NifS-like domain binds a persulfide intermediate, which is abstracted from the substrate L-cysteine and finally needs to be transferred to the Moco of aldehyde oxidase and xanthine oxidoreductase. In addition to Cys430, another eight cysteine residues are located in the NifS-like domain, with two of them being highly conserved among Moco sulfurase proteins and, at the same time, being in close proximity to Cys430. By determination of the number of surface-exposed cysteine residues and the number of persulfide-binding cysteine residues in combination with the sequential substitution of each of the nine cysteine residues, a second persulfide-binding cysteine residue, Cys206, was identified. Furthermore, the active-site Cys430 was found to be located on top of a loop structure, formed by the two flanking residues Cys428 and Cys435, which are likely to form an intramolecular disulfide bridge. These findings are confirmed by a structural model of the NifS-like domain, which indicates that Cys428 and Cys435 are within disulfide bond distance and that a persulfide transfer from Cys430 to Cys206 is indeed possible.
Changes in the ratio of free NEDD8 to ubiquitin triggers NEDDylation by ubiquitin enzymes
Authors: Hjerpe Roland , Thomas Yann , Chen Jesse , Zemla Aleksandra , Curran Siobhan , Shpiro Natalia , Dick Lawrence R. , Kurz Thimo
Published: October 2011

Ubiquitin and UBL (ubiquitin-like) modifiers are small proteins that covalently modify other proteins to alter their properties or behaviours. Ubiquitin modification (ubiquitylation) targets many substrates, often leading to their proteasomal degradation. NEDD8 (neural-precursor-cell-expressed developmentally down-regulated 8) is the UBL most closely related to ubiquitin, and its best-studied role is the activation of CRLs (cullin-RING ubiquitin ligases) by its conjugation to a conserved C-terminal lysine residue on cullin proteins. The attachment of UBLs requires three UBL-specific enzymes, termed E1, E2 and E3, which are usually well insulated from parallel UBL pathways. In the present study, we report a new mode of NEDD8 conjugation (NEDDylation) whereby the UBL NEDD8 is linked to proteins by ubiquitin enzymes in vivo. We found that this atypical NEDDylation is independent of classical NEDD8 enzymes, conserved from yeast to mammals, and triggered by an increase in the NEDD8 to ubiquitin ratio. In cells, NEDD8 overexpression leads to this type of NEDDylation by increasing the concentration of NEDD8, whereas proteasome inhibition has the same effect by depleting free ubiquitin. We show that bortezomib, a proteasome inhibitor used in cancer therapy, triggers atypical NEDDylation in tissue culture, which suggests that a similar process may occur in patients receiving this treatment.
Ectopic ACTH-syndrome due to a Neuroendocrine Tumour of the Appendix
Authors: Perakakis N. , Laubner K. , Keck T. , Steffl D. , Lausch M. , Meyer P. , Burger D. , Csanadi A. , Seufert J.
Published: October 2011

Ectopic ACTH production causes 10% of Cushing’s syndromes. The diagnostic workup is difficult, can last more than 6 months (> 50% of cases), and the underlying tumour is still frequently not located (12%). Carcinoid tumours of the appendix are frequent and are revealed in 0.3% of patients undergoing routine appendectomy. However, neuroendocrine tumours of the appendix with ACTH production are an extremely rare entity.

Here we report the case of a female patient with clinically overt Cushing’s syndrome due to ectopic ACTH-production from a carcinoid tumour of the appendix. During the diagnostic workup, repeated endocrine tests, multiple different imaging modalities and frequent and lengthy hospitalisations were necessary. Wrongly, even a neurosurgical pituitary exploration was performed. After 12 months from the initial admission, the tumour was finally detected by an 18F-fluoro-L-dihydroxyphenylalanine (18FDOPA PET) and an appendectomy followed by right hemicolectomy were performed. The patient recovered rapidly and the symptoms from the hypercortisolism were no more present.

In this case, we discuss the multitude of problems, which may delay the diagnosis and the pitfalls, that should be avoided in order to locate the tumour and to initiate adequate therapy as early as possible. Furthermore, our case demonstrates the complexity of diagnostic procedures, which demand most of the times a multidisciplinary approach. In this setting, regular follow-ups in short time intervals and the use of novel imaging techniques can finally cut the diagnostic “Gordian knot”.
Chaotrope vs. kosmotrope: Which one has lower friction?
Authors: He Yi , Shao Qing , Chen Shengfu , Jiang Shaoyi
Published: October 2011

We examine the frictional properties of zwitterionic surfaces and explore whether chaotropic or kosmotropic charged groups are preferred to achieve lower friction. Self-assembled monolayers of carboxybetaine (CB-SAMs) and sulfurbetaine (SB-SAMs) are used as model surfaces as they contain the same positively charged group, but different negatively charged ones. The negatively charged groups are kosmotropic carboxylates in the CB-SAM surfaces and chaotropic sulfonate groups in the SB-SAM surfaces, respectively. The results show that the friction of the SB-SAM surfaces is even lower than that of the CB-SAM surfaces although both surfaces have low friction. This suggests that chaotropic charged groups are better in reducing friction than kosmotropic groups. The lower friction of the SB-SAM surfaces over the CB-SAM can be explained by the higher mobility of water near the SB-SAM surfaces, as shown in the survival autocorrelation function and the dipole autocorrelation function of hydration water molecules.
A travelling photothermal technique employing pyroelectric detection to measure thermal diffusivity of films and coatings
Authors: Philip J. , Manjusha M. V. , Soumya H.
Published: October 2011

A travelling thermal wave technique employing optical excitation and pyroelectric detection of thermal waves propagating along a material film/coating on a substrate is described. The method enables direct measurement of thermal diffusivity. The technique involves measurement of the phase lag undergone by an optically excited thermal wave as it propagates along the coating. The set up has been automated for convenient and fast data acquisition and analysis. The technique has been adapted to measurement of thermal diffusivity of a commercial paint sample coated on glass and copper substrates. It is found that thermal diffusivity of the coating is independent of the thermal conductivity of the substrate. Dependence of thermal diffusivity on coating thickness shows exponential increase, with value reaching a constant at a characteristic high thickness. Measurements have been carried out on a few other samples with wide variations in thermal diffusivity, and the results compared with available reports or results obtained following other techniques. Analyses of the results show that the technique allows measurement of thermal diffusivity of coatings and films with uncertainties better than ±2.5%.
Simulations of light induced processes in water based on ab initio path integrals molecular dynamics. II. Photoionization
Authors: Svoboda Ondřej , Ončák Milan , Slavíček Petr
Published: October 2011

We have applied ab initio based reflection principle to simulate photoelectron spectra of small water clusters, ranging from monomer to octamer. The role of quantum and thermal effects on the structure of the water photoelectron spectra is discussed within the ab initio path integral molecular dynamics (PIMD) framework. We have used the PIMD method with up to 40 beads to sample the ground state quantum distribution at temperature T = 180 K. We have thoroughly tested the performance of various density functionals (B3LYP, BHandHLYP, M06HF, BNL, LC-ωPBE, and CAM-B3LYP) for the ionization process description. The benchmarking based on a comparison of simulated photoelectron spectra to experimental data and high level equation-of-motion ionization potential coupled clusters with singles and doubles calculations has singled out the BHandHLYP and LC-ωPBE functionals as the most reliable ones for simulations of light induced processes in water. The good performance of the density functional theory functionals to model the water photoelectron spectra also reflects their ability to reliably describe open shell excited states. The width of the photoelectron spectrum converges quickly with the cluster size as it is controlled by specific interactions of local character. The peak position is, on the other hand, defined by long-range non-specific solvent effects; it therefore only slowly converges to the corresponding bulk value. We are able to reproduce the experimental valence photoelectron spectrum of liquid water within the combined model of the water octamer embedded in a polarizable dielectric continuum. We demonstrate that including the long-range polarization and the state-specific treatment of the solvent response are needed for a reliable liquid water ionization description.
Design and use of an Elsässer probe for analysis of Alfvén wave fields according to wave direction
Authors: Drake D. J. , Kletzing C. A. , Skiff F. , Howes G. G. , Vincena S.
Published: October 2011

We have designed an electric and magnetic field probe which simultaneously measure both quantities in the directions perpendicular to the background magnetic field for application to Alfvén wave experiments in the Large Plasma Device at UCLA. This new probe allows for the projection of measured wave fields onto generalized Elsässer variables. Experiments were conducted in a singly ionized He plasma at 1850 G in which propagation of Alfvén waves was observed using this new probe. We demonstrate that a clear separation of transmitted and reflected signals and determination of Poynting flux and Elsässer variables can be achieved.
Sizes of large He droplets
Authors: Gomez Luis F. , Loginov Evgeny , Sliter Russell , Vilesov Andrey F.
Published: October 2011

Helium droplets spanning a wide size range, NHe = 103–1010, were formed in a continuous-nozzle beam expansion at different nozzle temperatures and a constant stagnation pressure of 20 bars. The average sizes of the droplets have been obtained by attenuation of the droplet beam through collisions with argon and helium gases at room temperature. The results obtained are in good agreement with previous measurements in the size range NHe = 105–107. Moreover, the measurements give the average sizes in the previously uncharacterized range of very large droplets of 107–1010 atoms. The droplet sizes and beam flux increase rapidly at nozzle temperatures below 6 K, which is ascribed to the formation of droplets within the nozzle interior. The mass spectra of the droplet beam upon electron impact ionization have also been obtained. The spectra show a large increase in the intensity of the He4+ signal upon increase of the droplet size, an effect which can be used as a secondary size standard in the droplet size range NHe = 104–109 atoms.
Polariton lasing in a hybrid bulk ZnO microcavity
Authors: Guillet T. , Mexis M. , Levrat J. , Rossbach G. , Brimont C. , Bretagnon T. , Gil B. , Butté R. , Grandjean N. , Orosz L. , Réveret F. , Leymarie J. , Zúñiga-Pérez J. , Leroux M. , Semond F. , Bouchoule S.
Published: October 2011

We demonstrate polariton lasing in a bulk ZnO planar microcavity under non-resonant optical pumping at a small negative detuning (δ ∼ −1/6 the 130 meV vacuum Rabi splitting) and a temperature of 120 K. The strong coupling regime is maintained at lasing threshold since the coherent nonlinear emission from the lower polariton branch occurs at zero in-plane wavevector well below the uncoupled cavity mode. The contribution of multiple localized polariton modes above threshold and the non-thermal polariton statistics show that the system is in a far-from-equilibrium regime, likely related to the moderate photon lifetime and in-plane photonic disorder in the cavity.
Guided self-assembly of electrostatic binary monolayers via isothermal-isobaric control
Authors: Shestopalov Nickolay V. , Henkelman Graeme , Rodin Gregory J.
Published: October 2011

Self-assembly of a binary monolayer of charged particles is modeled using molecular dynamics and statistical mechanics. The equilibrium phase diagram for the system has three distinct phases: an ionic crystal; a geometrically ordered crystal with disordered charges; and a fluid. We show that self-assembly occurs near the phase transition between the ionic crystal and the fluid, and that the rate of ordering is sensitive to the applied pressure. By assuming an Arrhenius form for the rate of ordering, an optimality condition for the temperature and pressure is derived that maximizes the rate. Using the Clausius-Clapeyron equation, the optimal point on the phase boundary is expressed in terms of the thermodynamic changes in state variables across the boundary. The predicted optimal temperature and pressure conditions are in good agreement with numerical simulations and result in self-organization rates five times that of a simulation without applied pressure.
Precise simulation of the freezing transition of supercritical Lennard-Jones
Authors: Nayhouse Michael , Amlani Ankur M. , Orkoulas G.
Published: October 2011

The fluid-solid transition of the Lennard-Jones model is analyzed along a supercritical isotherm. The analysis is implemented via a simulation method which is based on a modification of the constrained cell model of Hoover and Ree. In the context of hard-sphere freezing, Hoover and Ree simulated the solid phase using a constrained cell model in which each particle is confined within its own Wigner-Seitz cell. Hoover and Ree also proposed a modified cell model by considering the effect of an external field of variable strength. High-field values favor configurations with a single particle per Wigner-Seitz cell and thus stabilize the solid phase. In previous work, a simulation method for freezing transitions, based on constant-pressure simulations of the modified cell model, was developed and tested on a system of hard spheres. In the present work, this method is used to determine the freezing transition of a Lennard-Jones model system on a supercritical isotherm at a reduced temperature of 2. As in the case of hard spheres, constant-pressure simulations of the fully occupied constrained cell model of a system of Lennard-Jones particles indicate a point of mechanical instability at a density which is approximately 70% of the density at close packing. Furthermore, constant-pressure simulations of the modified cell model indicate that as the strength of the field is reduced, the transition from the solid to the fluid is continuous below the mechanical instability point and discontinuous above. The fluid-solid transition of the Lennard-Jones system is obtained by analyzing the field-induced fluid-solid transition of the modified cell model in the high-pressure, zero-field limit. The simulations are implemented under constant pressure using tempering and histogram reweighting techniques. The coexistence pressure and densities are determined through finite-size scaling techniques for first-order phase transitions which are based on analyzing the size-dependent behavior of susceptibilities and dimensionless moment ratios of the order parameter.
All-electron time-dependent density functional theory with finite elements: Time-propagation approach
Authors: Lehtovaara Lauri , Havu Ville , Puska Martti
Published: October 2011

We present an all-electron method for time-dependent density functional theory which employs hierarchical nonuniform finite-element bases and the time-propagation approach. The method is capable of treating linear and nonlinear response of valence and core electrons to an external field. We also introduce (\documentclass[12pt]{minimal}\begin{document}$\text{i}$\end{document}i) a preconditioner for the propagation equation, (\documentclass[12pt]{minimal}\begin{document}$\text{ii}$\end{document}ii) a stable way to implement absorbing boundary conditions, and (\documentclass[12pt]{minimal}\begin{document}$\text{iii}$\end{document}iii) a new kind of absorbing boundary condition inspired by perfectly matched layers.
In-situ guidance of individual neuronal processes by wet femtosecond-laser processing of self-assembled monolayers
Authors: Yamamoto Hideaki , Okano Kazunori , Demura Takanori , Hosokawa Yoichiroh , Masuhara Hiroshi , Tanii Takashi , Nakamura Shun
Published: October 2011

In-situ guidance of neuronal processes (neurites) is demonstrated by applying wet femtosecond-laser processing to an organosilane self-assembled monolayer (SAM) template. By scanning focused laser beam between cell adhesion sites, on which primary neurons adhered and extended their neurites, we succeeded in guiding the neurites along the laser-scanning line. This guidance was accomplished by multiphoton laser ablation of cytophobic SAM layer and subsequent adsorption of cell adhesion molecule, laminin, onto the ablated region. This technique allows us to arbitrarily design neuronal networks in vitro.
Structural, magnetic, and magnetotransport properties of NiMnSb thin films deposited by flash evaporation
Authors: Anh Tuan Nguyen , Phuc Duong Nguyen
Published: October 2011

To date, the use of flash evaporation (FE) as a deposition technique for NiMnSb thin films has not yet been reported. In this letter, we report on NiMnSb thin films deposited on heated Si (111) substrates at 300 °C via FE. Investigations of the structural characteristics and magnetic and magnetotransport properties of these thin films show typical features of a half-metallic ferromagnetic semi-Heusler alloy. The origin of the film’s extraordinary magnetotransport behavior is examined under the perspective of spin-order levels attached to a grain-grain boundary-type structure.
Effect of bottom electrodes on nanoscale switching characteristics and piezoelectric response in polycrystalline BiFeO3 thin films
Authors: Yan F. , Zhu T. J. , Lai M. O. , Lu L.
Published: October 2011

We have investigated the nanoscale switching characteristics and piezoelectric response based on polycrystalline BiFeO3 (BFO) thin films with different orientations deposited on different oxide bottom electrodes. The BFO film deposited on the LaNiO3 (LNO)-coated Si substrate shows a (001) preferred orientation and higher ferroelectric properties, while the BFO film grown on the SrRuO3 (SRO) buffered Si substrate shows a random orientation. The domain structures have been determined via piezoresponse force microscopy (PFM) for both films, predicting that the BFO film with the LNO bottom electrode has a larger piezoelectricity property corresponding to the ferroelastic domain. Through local switching spectroscopy measurements, the evidence of ferroelectric switching and the origin of the enhanced piezoresponse properties have been provided. A greatly improved piezoelectric response has been demonstrated using PFM that is 66.8 pm V−1 for the BFO with a SRO bottom electrode, while we obtain a value of 348.2 pm V−1 for the BFO with a LNO bottom electrode due to the increased density of the polarization vectors along the external electrical field.
A heterojunction modulation-doped Mott transistor
Authors: Son Junwoo , Rajan Siddharth , Stemmer Susanne , James Allen S.
Published: October 2011

A heterojunction Mott field effect transistor (FET) is proposed that consists of an epitaxial channel material that exhibits an electron correlation induced Mott metal-to-insulator transition. The Mott material is remotely (modulation) doped with a degenerately doped conventional band insulator. An applied voltage modulates the electron transfer from the doped band insulator to the Mott material and produces transistor action by inducing an insulator-to-metal transition. Materials parameters from rare-earth nickelates and SrTiO3 are used to assess the potential of the “modulation-doped Mott FET” (ModMottFET or MMFET) as a next-generation switch. It is shown that the MMFET is characterized by unique “charge gain” characteristics as well as competitive transconductance, small signal gain, and current drive.
Effect of excitation pulse width on thermoacoustic signal characteristics and the corresponding algorithm for optimization of imaging resolution
Authors: Lou Cunguang , Nie Liming , Xu Dong
Published: October 2011

Thermoacoustic (TA) signal amplitude, waveform, and spatial resolution related to width of the excitation pulse were theoretically explained and simulated by finite-difference time-domain (FDTD) method. TA signals and the reconstructed TA images were compared under variable microwave pulse widths tunable from 400 to 1200 ns to analyze the relationships. The peak-to-peak interval of TA signals increase and the spatial resolution of TA images decrease with the increment of the excitation pulse width in the long pulse region. Also, the experimental results clearly reveal that the TA conversion efficiency decrease with increasing microwave pulse duration under the same peak power, which have a good agreement with the theoretical predication and FDTD simulation.