bluuebunny/crossref_metadata_2025 huggingface dataset:
The relic Criollo cacao in Belize – genetic diversity and relationship with Trinitario and other cacao clones held in the International Cocoa Genebank, Trinidad
Authors: Motilal Lambert A. , Zhang Dapeng , Umaharan Pathmanathan , Mischke Sue , Mooleedhar Vishnarayan , Meinhardt Lyndel W.
Published: January 2010

Cacao (Theobroma cacaoL.) was domesticated in Mesoamerica and is native to the South American rainforest. Belizean Criollo is a group of relic landraces that are thought to be similar to those used by the Olmecs and Mayans during early domestication. Knowledge of genetic diversity is essential for efficient conservation and use of these relic landraces. Using 30 microsatellite markers, we characterized genetic diversity in 77 Belize Criollo accessions collected from the Maya Mountains in Belize, and assessed their relationship with 62 cacao accessions including 25 Trinitario accessions. Genetic diversity and heterozygosity were low in Belizean Criollo germplasm. Eleven distinctive genotypes were identified among the Belizean germplasm. Results of ordination and cluster analysis supported their putative ancestral contribution to the Trinitario cacao. However, results of Bayesian assignment and parentage analysis both suggested that the contribution of Criollo cacao to the Imperial College Selections Trinitario is small. Our preferred hypothesis for the genesis of Trinitario cacao is that a limited population of Criollo × Forastero hybrids emanated from the introduced Forastero population of Trinidad. The present study provides new insights into the origin of the Trinitario cacao, which will be useful in theex situandin situconservation of cacao landraces from Mesoamerica.
Cultural Diplomacy as Cultural Globalization: The University of Michigan Jazz Band in Latin America
Authors: FOSLER-LUSSIER DANIELLE
Published: January 2010

From January to May 1965 the University of Michigan Jazz Band traveled extensively in Latin America for the State Department's Cultural Presentations Program. This tour serves as a case study through which we can see the far-reaching effects of cultural diplomacy. The State Department initially envisioned its cultural and informational programs as one-way communication that brought ideas from the United States to new places; yet the tours changed not only audiences, but also the musicians themselves and even the communities to which the musicians returned. Both archival and oral history evidence indicate that the Michigan jazz band's tour succeeded in building vital imagined connections across international borders. The nature of these connections demonstrates that the cold war practice of pushing culture across borders for political purposes furthered cultural globalization—even though the latter process is often regarded by scholars as a phenomenon that began only after the end of the cold war. The jazz band's tour highlights the essential role of music and musicians in fostering new transnational sensibilities in the politicized context of the cold war.
Vom Sehen zum Schauen
Authors: Köhl Markus
Published: January 2010

Zusammenfassung. Ein produktiver Umgang mit den Sinnen kommt besonders im Bereich der Kunsttherapie zur Anwendung. Die physiologischen, sinnlichen Abläufe und eine mental offene Verfassung eines Künstlers sind genauso ausschlaggebend bei Therapeuten und Patienten in der Kunsttherapie. Das künstlerische Ziel liegt darin, das innere Unsichtbare wahrzunehmen und in einem schöpferischen Prozess auf die Bildebene zu projizieren. Der Maler und Wahrnehmungsexperte Willi Baumeister schreibt, dass ein freies, inspiriertes Schauen mit einer entspannten inneren Einstellung den Weg zum Unbekannten in der Kunst öffnet. Eine Forschungsarbeit überträgt diese Gedanken auf den kunsttherapeutischen Prozess und das dabei stattfindende empathiefähige Wahrnehmen und Handeln. Durch ein Vegetativportrait, gemessen mit einem multiparametrischen Messverfahren, wird dargestellt, dass in einem Zustand mentaler Entspannung und durch größere Aufmerksamkeitsressourcen mehr Kapazitäten zur internen höheren geistigen Verarbeitung erweiterter Wahrnehmungsspektren möglich werden. Das Gehirn zeigt bei vertieftem Bewusstsein eine Tendenz zur Kohärenz der unterschiedlichen Gehirnareale, wobei kohärente Momente entstehen, die tiefe, prägende und neue Denkstrukturen entstehen lassen. Diese Ergebnisse sind ausschlaggebend für den Therapeuten, den Patienten und darüberhinaus für die Empathie in ihrer gegenseitigen Beziehung im kunsttherapeutischen Prozess. Vorher verschlossene Bereiche und eigene Ressourcen öffnen sich, die zur Stärkung des Selbstbewusstseins und zur Heilung beitragen werden. Der Fokus des Therapeuten und Patienten ist beiderseits beobachtend ausgerichtet. Kunsttherapeutische Werkprozesse werden durch den Therapeuten und Patienten in einem Zustand wachen, ahnenden Beobachtens wahrgenommen.
Cyberbullying Versus Face-to-Face Bullying
Authors: Dooley Julian J. , Pyżalski Jacek , Cross Donna
Published: January 2010

Cyberbullying has been described as a type of electronic bullying and has recently been subjected to intense media scrutiny largely due to a number of high profile and tragic cases of teen suicide. Despite the media attention relatively little is known about the nature of cyberbullying. This is, at least in part, due to a lack of theoretical and conceptual clarity and an examination of the similarities and differences between cyberbullying and face-to-face bullying. This paper reviews the limited theoretical and empirical literature addressing both cyberbullying and face-to-face bullying, using some specific examples from a qualitative study for illustration. We compare and contrast individual factors common to cyber and face-to-face bullying. We then examine social information processing factors associated with face-to-face bullying and present a discussion of the similarities and differences that may characterize cyberbullying.
Behind the Scenes and Screens
Authors: Spears Barbara , Slee Phillip , Owens Larry , Johnson Bruce
Published: January 2010

This qualitative study explores the human dimension of two subtypes of bullying in an Australian schooling context. Individuals’ knowledge, understanding, and experiences of covert (behind the scenes) and cyber (behind the screens) bullying were explored through stories of what has actually been occurring in and around their schools. Participants were adolescent students (n = 20), teachers (n = 10) and school counselors (n = 6) from a variety of schools across Adelaide, South Australia. They recounted stories about covert and cyberbullying from their social networks and schooling contexts, giving authentic “voice” to these behaviors. Each narrative was uploaded to a dedicated website, contributing to an online “storybook,” and providing information rich cases that enabled “issues of central importance” ( Patton, 1987 ) to emerge. Narrative and thematic analyses revealed that covert and cyberbullying have much in common, but that cyberbullying in particular evoked strong negative feelings and emotions which included fear, as well as disruption to and dislocation from the participants’ relationships. Participants indicated that the power differential was clearly understood and there was a clear sense of helplessness associated with cyberbullying. In particular, cyberbullying was found to operate both covertly and overtly via e-technologies, across school and home boundaries.
The Emotional Impact on Victims of Traditional Bullying and Cyberbullying
Authors: Ortega Rosario , Elipe Paz , Mora-Merchán Joaquín A. , Calmaestra Juan , Vega Esther
Published: January 2010

We examine the emotional impact caused to victims of bullying in its traditional form, both directly and indirectly, as well as bullying inflicted by use of new technologies such as mobile phones and the Internet. A sample of 1,671 adolescents and young people responded to a questionnaire which asked if they had been victims of various forms of bullying, as well as the emotions this caused. The results show that although traditional bullying affected significantly more young people than cyberbullying, the latter affected one in ten adolescents. Analysis of the emotions caused showed that traditional bullying produced a wide variety of impacts, with the victims being divided into five different emotional categories, while indirect bullying and cyberbullying presented a narrower variety of results with the victims being classifiable into just two groups: Those who said that they had not been emotionally affected and those who simultaneously suffered from a wide variety of negative emotions. The influence of age, gender, and severity on each emotional category is also analyzed.
Traditional Bullying and Cyberbullying
Authors: Gradinger Petra , Strohmeier Dagmar , Spiel Christiane
Published: January 2010

We investigated the co-occurrence of traditional bullying, cyberbullying, traditional victimization, and cybervictimization, and analyzed whether students belonging to particular groups of bullies (e.g., traditional, cyber, or both), victims (e.g., traditional, cyber, or both), and bully-victims differed regarding adjustment. Seven hundred sixty-one adolescents (49% boys) aged 14–19 years (M = 15.6 years) were surveyed. More students than expected by chance were totally uninvolved, more students were traditional bully-victims, and more students were combined bully-victims (traditional and cyber). The highest risks for poor adjustment (high scores in reactive and instrumental aggression, depressive, and somatic symptoms) were observed in students who were identified as combined bully-victims (traditional and cyber). In addition gender differences were examined.
Investigating Measures of Achievement Motivation(s)
Authors: Ziegler Matthias , Schmukle Stefan , Egloff Boris , Bühner Markus
Published: January 2010

After a long debate there is now growing agreement that implicit and explicit achievement motivation can be seen as distinct constructs. One of their major differences lies in their predictive validity, which supposedly differs depending on the setting. Empirical evidence exists to the effect that different explicit measures based on different theoretical concepts build one construct. For implicit measures, however, such evidence is lacking. Thus, scores on three implicit and three explicit achievement motivation measures, an intelligence test, and a Big 5 questionnaire were obtained (N = 150) as well as two criteria. The explicit achievement motivation measures were classified as being based either on Murray’s or on McClelland’s theory. Results replicate the idea of a common construct for explicit measures but not for implicit measures. The assumed predictions did not occur for all tests and disappeared when controlling for intelligence.
Sex Differences on the German Wechsler Intelligence Test for Children (WISC-IV)
Authors: Goldbeck Lutz , Daseking Monika , Hellwig-Brida Susanne , Waldmann Hans C. , Petermann Franz
Published: January 2010

This study investigates cognitive sex differences in child and adolescent intelligence as measured by the WISC-IV (German edition; Petermann & Petermann, 2007 ). It was hypothesized that there would be no differences attributable to sex in Full Scale IQ (FSIQ), but on various composite score levels. Sex effects were expected to be more pronounced during/after puberty than before. Method: The standardization sample of the German WISC-IV (N = 1650) was used to assess and evaluate sex differences in test performance across defined age groups (6–9, 10–12, and 13–16 years). Results: At all ages, there were no gender effects in the Full-Scale IQ, but gender effects favoring boys in the Verbal Comprehension Index (t = 3.94, p < .001, d = .19) and Perceptual Reasoning Index (t = 2.69, p = .007, d = .13). In the Processing Speed Index, girls scored higher than boys (t = 6.75, p < .001, d = .33). No significant sex-by-age interaction effect was found using ANOVA, but various 1-df contrasts showed substantial sex differences at specific ages. Conclusions: Results are discussed in the context of the specific constructs measured by the WISC-IV, taking into account recent findings in neurobiological and developmental psychology.
Vulnerability Factors for Bipolar Disorders as Predictors of Attributions in Ability-Based and Chance-Based Tests
Authors: Meyer Thomas D. , Barton Stephen , Baur Marina , Jordan Gabriele
Published: January 2010

The role of attributional style in bipolar disorder has received empirical support. Research suggests that a pattern of global, stable, and possibly internal attributions for positive events might even trigger mania. We tested whether hypothesized risk factors for bipolar disorder are associated with such attributions after feedback of success in an ability- and chance-based test. University students (n = 115) completed the Behavioral Inhibition and Behavioral Activation Scales (BIS/BAS) and the Hypomanic Personality Scale (HPS) to assess risk for bipolar disorder. In addition, participants were interviewed using the Structured Clinical Interview. All participants performed an ability-based (intelligence) test and a chance-based (dice-throwing) test, and success was induced by providing positive feedback regardless of their actual test performance. Attributions of perceived success were assessed after each test. Results showed that high scores on the BAS scale were generally predictive of self-serving attributions in the ability-based test, while scores on the HPS predicted a more global and self-serving attributional style in the chance-based test. Current depression, lifetime affective disorder, BIS, or the dysregulation of the BAS did not consistently predict attributions on either test. Despite some methodological limitations, results suggest that anticipated or experienced success in skill-related contexts triggers self-serving attributions in individuals scoring high on the BAS scale, while perceived positive outcome in chance-related, more unrealistic contexts triggers similar attributions in individuals scoring high on the HPS. Future research has to examine whether these overly positive attributions after positive, chance-related situations are a stable characteristic with respect to vulnerability to mania.
Morningness-Eveningness and Eating Disorders in a Sample of Adolescent Girls
Authors: Schmidt Sarah , Randler Christoph
Published: January 2010

Eating disorders and morningness-eveningness preferences are presumed to be associated with each other. We tested this hypothesis in an adolescent population using a questionnaire for morningness (CSM) and three scales of the EDI-2: drive for thinness, bulimic behavior, and body dissatisfaction. After controlling for age and BMI, we found a positive association between eveningness and all three scales; evening-oriented girls reported higher values in eating disorders. There was a positive correlation between body dissatisfaction and drive for thinness on the one side and bedtimes during the week and on the weekend on the other, again supporting the view that eveningness and eating disorders are associated. The association between circadian preference and eating disorders thus emerges already in adolescence.
Correspondence Between the General Ability to Discriminate Sensory Stimuli and General Intelligence
Authors: Meyer Christine Sandra , Hagmann-von Arx Priska , Lemola Sakari , Grob Alexander
Published: January 2010

For more than a century the veracity of Spearman’s postulate that there is a nearly perfect correspondence between general intelligence and general sensory discrimination has remained unresolved. Most studies have found significant albeit small correlations. However, this can be used neither to confirm nor dismiss Spearman’s postulate, a major weakness of previous research being that only single discrimination capacities were considered rather than general discrimination. The present study examines Spearman’s hypothesis with a sample of 1,330 5- to 10-year-old children, using structural equation modeling. The results support Spearman’s hypothesis with a strong correlation (r = .78). Results are discussed in terms of the validity of the general sensory discrimination factor. In addition, age-group-specific analyses explored the age differentiation hypothesis.
A stochastic formulation for erosion of cohesive sediments
Authors: Van Prooijen B. C. , Winterwerp J. C.
Published: January 2010

The linear formulation for erosion E = M(τb−τc), often applied in engineering applications, has two properties, which do not always comply with field and laboratory observations, they are as follows: (1) The erosion rate is zero below the critical bed shear stress τc and increases linearly with bed shear stress τb, when exceeding the critical bed shear stress; incipient motion (τb ≃ τc) is poorly represented. (2) The erosion rate is constant in time for constant values of M and τc, whereas observations often suggest time dependency. In this paper we analyze the process of incipient motion and time dependency by using a stochastic forcing (bed shear stress) and a stochastic bed strength (critical bed shear stress). It is well known that the bed shear stress is not constant but varies due to turbulence. This stochastic nature of the turbulent motion is accounted for by a probability density distribution for the bed shear stress, which is based on the formulation of Hofland and Battjes (2006). This distribution is implemented in the linear erosion formulation. An analytical solution for the erosion rate is obtained, which only depends on the mean bed shear stress. A parametrization is made for efficient application in numerical models. The sediment in the bed is considered to be nonuniform. Therefore, it is subdivided into several classes, distinguished by the critical bed shear stress and not necessarily by the grain size. The variability of the critical bed shear stress is treated in a discritized way. Sediment balance equations are solved for each class. Considering different classes, the total erosion rate becomes time dependent, as the erosion depends on the availability of sediment. The model is applied to two annular flume data sets, Jacobs (2009) and Amos et al. (1992a). The results show that with a proper choice of the required parameters, the time dependence of the erosion rate and the concentration can be reproduced. We conclude that the occurrence of incipient motion can be explained from a stochastic forcing. Time‐varying erosion rates can be explained from a stochastic bed strength distribution or from a vertical gradient in bed strength. The latter is, however, not likely and not measurable in the top layers of dense consolidated cohesive sediment beds.
Decadal cooling in the Indian summer monsoon after 1997/1998 El Niño and its impact on the East Asian summer monsoon
Authors: Yun Kyung‐Sook , Ha Kyung‐Ja , Wang Bin , Ding Ruiqiang
Published: January 2010

Observational evidences are presented to show a significant atmospheric diabatic cooling in the Indian summer monsoon (ISM) region after the 1997/1998 El Niño. This study investigates the cause of this decadal cooling and its impact on the East Asian summer monsoon (EASM). After 1997/1998, the abnormal sea surface temperature warming in the western Pacific, which is not fully demonstrated in this study, induces enhanced local convection. This enhanced convection strengthens the Walker‐type circulation and leads to moisture divergence, subsidence, and decreased cloudiness over the ISM, which in turn causes the diabatic cooling. The decadal cooling of the ISM, on the other hand, may affect the EASM through development of an anomalous local meridional cell over the EASM region and through enhancement of the Eurasian wave train pattern. Consequently, rainfall over the ISM and northern EASM decreases concurrently, while the southern EASM rainfall increases after 1997/1998.
Mushy magma beneath Yellowstone
Authors: Chu Risheng , Helmberger Don V. , Sun Daoyuan , Jackson Jennifer M. , Zhu Lupei
Published: January 2010

A recent prospective on the Yellowstone Caldera discounts its explosive potential based on inferences from tomographic studies which suggests a high degree of crystallization of the underlying magma body. In this study, we show that many of the first teleseismic P‐wave arrivals observed at seismic stations on the edge of the caldera did not travel through the magma body but have taken longer but faster paths around the edge. After applying a number of waveform modeling tools, we obtain much lower seismic velocities than previous studies, 2.3 km/sec (Vp) and 1.1 km/sec (Vs). We estimate the physical state of the magma body by assuming a fluid‐saturated porous material consisting of granite and a mixture of rhyolite melt and water and CO2 at a temperature of 800°C and pressure at 5 km (0.1 GPa). We found that this relatively shallow magma body has a volume of over 4,300 km3 and is about 32% melt saturated with about 8% water plus CO2 by volume.
Self‐attenuation artifacts and correction factors of light element measurements by X‐ray analysis: Implication for mineral dust composition studies
Authors: Formenti P. , Nava S. , Prati P. , Chevaillier S. , Klaver A. , Lafon S. , Mazzei F. , Calzolai G. , Chiari M.
Published: January 2010

On a global scale, mineral dust is one of the major components of atmospheric aerosols and has important effects on the radiative budget of the atmosphere and thus on climate forcing. An accurate measurement of the concentration of crustal elements, namely Na, Mg, Al, Si, K, Ca, Ti, and Fe, is mandatory for the study of desert aerosols. The concentration of light elements, when measured by X‐ray emission techniques such as X‐ray fluorescence (XRF) and particle‐induced X‐ray emission (PIXE), can be underestimated owing to self‐absorption of the emitted soft X‐rays inside aerosol particles. In this work, we analyzed dust samples collected in field campaigns and samples produced in the laboratory using dust of known composition. Measurements have been conducted with PIXE and energy‐dispersive XRF (ED‐XRF), together with an attenuation‐free technique such as particle‐induced gamma‐ray emission (PIGE) and attenuation corrected wavelength‐dispersive XRF (WD‐XRF) by internal standard calibration. We focus on the determination of Al and present results of a PIXE versus PIGE intercomparison. Aluminum concentration was measured with both techniques in dust samples collected by aircraft sampling over western Africa during winter 2006 and summer 2007. An underestimation of the Al concentration determined by PIXE was observed (up to 40%), and it was compared with the results of a simple calculation using basic physics and the size distribution of the collected aerosol. Similar attenuation was observed for Mg, Al, and Si in the laboratory samples analyzed by ED‐XRF and WD‐XRF. In order to use concentration ratios involving light elements as tracers of the region of emission of the sampled dust, these artifacts (i.e., underestimation of the concentration of light elements) induced by self‐attenuation should be properly considered and corrected.
In situ analysis of ice table depth variations in the vicinity of small rocks at the Phoenix landing site
Authors: Sizemore H. G. , Mellon M. T. , Searls M. L. , Lemmon M. T. , Zent A. P. , Heet T. L. , Arvidson R. E. , Blaney D. L. , Keller H. U.
Published: January 2010

Prior to the Phoenix mission, ice stability simulations predicted that surface rocks at the landing site would produce depressions in the ice table (the boundary between dry and ice‐cemented soil) if ground ice at the site were in diffusive equilibrium with atmospheric water vapor. We use stereo images and digital elevation models to investigate variations in the depth of the ice table near two decimeter‐scale rocks at the Phoenix landing site and compare the observed depth variations to ice stability simulations. We find that ice table depth variations observed near rocks at the landing site are consistent with our theoretical predictions. Based on our results we conclude that: 1) Water transport in the near‐surface regolith occurs primarily via vapor diffusion; 2) Environmental conditions in which water transport is dominated by diffusion have been persistent at the landing site for 100s to 1000s of years or longer; that is, ground ice is in diffusive equilibrium with atmospheric water vapor; and 3) In diffusive equilibrium, thermal stability dictates the depth of the ice table on horizontal length scales as small as centimeters.
Design of a dynamic model of genes with multiple autonomous regulatory modules by evolution in silico
Authors: Spirov Alexander , Holloway David
Published: January 2010

A new approach to design a dynamic model of genes with multiple autonomous regulatory modules by evolution in silico is proposed. The approach is based on Genetic Algorithms, with new crossover operators especially designed for these purposes. The approach exploits the subbasin-portal architecture of the fitness functions suitable for this kind of evolutionary modeling. The effectiveness of the approach is demonstrated on a series of benchmark tests.
Inhibition of PTP1B by Trodusquemine (MSI‐1436) Causes Fat‐specific Weight Loss in Diet‐induced Obese Mice
Authors: Lantz Kristen A. , Hart Susan G. Emeigh , Planey Sonia L. , Roitman Mitchell F. , Ruiz‐White Inez A. , Wolfe Henry R. , McLane Michael P.
Published: January 2010

Trodusquemine (MSI‐1436) causes rapid and reversible weight loss in genetic models of obesity. To better predict the potential effects of trodusquemine in the clinic, we investigated the effects of trodusquemine treatment in a murine model of diet‐induced obesity (DIO). Trodusquemine suppressed appetite, reduced body weight (BW) in a fat‐specific manner, and improved plasma insulin and leptin levels in mice. Screening assays revealed that trodusquemine selectively inhibited protein‐tyrosine phosphatase 1B (PTP1B), a key enzyme regulating insulin and leptin signaling. Trodusquemine significantly enhanced insulin‐stimulated tyrosine phosphorylation of insulin receptor (IR) β and STAT3, direct targets of PTP1B, in HepG2 cells in vitro and/or hypothalamic tissue in vivo. These data establish trodusquemine as an effective central and peripheral PTP1B inhibitor with the potential to elicit noncachectic fat‐specific weight loss and improve insulin and leptin levels.
Decreased Serum Hepcidin and Improved Functional Iron Status 6 Months After Restrictive Bariatric Surgery
Authors: Tussing‐Humphreys Lisa M. , Nemeth Elizabeta , Fantuzzi Giamila , Freels Sally , Holterman Ai‐Xuan L. , Galvani Carlos , Ayloo Subhashini , Vitello Joseph , Braunschweig Carol
Published: January 2010

Excess adiposity is associated with low‐grade inflammation and decreased iron status. Iron depletion in obesity is thought to be mediated by an inflammation‐induced increase in the body's main regulator of iron homeostasis, hepcidin. Elevated hepcidin can result in iron depletion as it prevents the release of dietary iron absorbed into the enterocytes, limiting replenishment of body iron losses. Weight reduction is associated with decreased inflammation; however, the impact of reduced inflammation on iron status and systemic hepcidin in obese individuals remains unknown. We determined prospectively the impact of weight loss on iron status parameters, serum hepcidin, inflammation, and dietary iron in 20 obese premenopausal females 6 months after restrictive bariatric surgery. At baseline, the presence of iron depletion was high with 45% of the women having serum transferrin receptor (sTfR) >28.1 nmol/l. Differences between baseline and 6 months after surgery for BMI (47.56 vs. 39.55 kg/m2; P < 0.0001), C‐reactive protein (CRP) (10.83 vs. 5.71 mg/l; P < 0.0001), sTfR (29.97 vs. 23.08 nmol/l; P = 0.001), and serum hepcidin (111.25 vs. 31.35 ng/ml; P < 0.0001) were significantly lower, whereas hemoglobin (Hb) (12.10 vs. 13.30 g/dl; P < 0.0001) and hematocrit (Hct) (36.58 vs. 38.78%; P = 0.001) were significantly higher. Ferritin and transferrin saturation (Tsat) showed minimal improvement at follow‐up. At baseline, hepcidin was not correlated with sTfR (r = 0.02); however, at follow‐up, significant correlations were found (r = −0.58). Change in interleukin‐6 (IL‐6) from baseline was marginally associated with decreased log serum hepcidin (Δ IL‐6: β = −0.22; P = 0.15), whereas change in BMI or weight was not. No significant difference in dietary iron was noted after surgery. Weight loss in obese premenopausal women is associated with reduced serum hepcidin and inflammation. Reduction in inflammation and hepcidin likely allow for enhanced dietary iron absorption resulting in an improved functional iron profile.
Drastic selectivity reversal on crown-ether based ion-sensing membranes made of ordered mesoporous silica and conventional sol–gel derived one
Authors: Yajima Setsuko , Nakajima Takahito , Higashi Mariko , Kimura Keiichi
Published: January 2010

A crown-ether based ion sensor with mesoporous silica membrane was fabricated for the first time, and drastic selectivity reversal was attained in comparison with conventional sol–gel-derived membrane based on the same crown ether.
The cascade carbo-carbonylation of unactivated alkenes catalyzed by an organocatalyst and a transition metal catalyst: a facile approach to γ-diketones and γ-carbonyl aldehydes from arylalkenes under air
Authors: Xie Jin , Huang Zhi-Zhen
Published: January 2010

A novel cascade carbon-carbonylation reaction of unactivated arylalkenes with ketones or aldehydes was catalyzed by an organocatalyst and a transition metal catalyst via a SOMO-enamine under air.
Synthesis, structure and reactions of triarylgermyl anion with α,δ-ambiphilic character
Authors: Kawachi Atsushi , Machida Koji , Yamamoto Yohsuke
Published: January 2010

Benzosilagermacyclobutene 2 bearing two Ar groups on the germanium atom [Ar = o-(fluorodimethylsilyl)phenyl] undergoes Ge–Si bond cleavage with KF in the presence of a cryptand to form Ar3Ge−[K+(cryptand)] 3, α,δ-ambiphilic species, which is converted back into 2 in the presence of LiBPh4·3dme or BF3·Et2O.
Metal-dependent alternative activation of O–H and C–H bonds of methanol: on the formation and structure of “bare” [M,C,H3,O]+ complexes (M = Fe, Co, Ni) in the gas phase
Authors: Schlangen Maria , Schwarz Helmut
Published: January 2010

Different metals, different ions: specific activations of O–H or C–H bonds of methanol during electrospray ionization (ESI) result in different gas-phase ions [M − OCH3]+ or [M − CH2OH]+, respectively (M = Fe, Co, Ni).
α-Functionalization of non-activated aliphatic amines: ruthenium-catalyzed alkynylations and alkylations
Authors: Jovel Irina , Prateeptongkum Saisuree , Jackstell Ralf , Vogl Nadine , Weckbecker Christoph , Beller Matthias
Published: January 2010

Catalytic α-alkylations and -alkynylations of non-activated aliphatic amines with silylated alkynes proceed selectively in the presence of the Shvo catalyst.
Evaluation and Monitoring of Office Markets
Authors: Malcata-Rebelo Emília , Pinho Paulo
Published: January 2010

The main aim of this study is to understand the relevant variables underlying the mechanisms of office supply, office demand, and market equilibrium to support municipal decision-making processes. Public decisions, at the local level, are expected to ensure that office prices are kept under control, avoiding the speculative behaviour of real-estate agents, and are able to prepare appropriate forms of intervention over supply and demand, in the short term as well as in the medium or long term. In order to reach these goals an identification of the most relevant variables that shape office supply and office demand and their respective elasticities is carried out, and ongoing supply, demand, and market equilibrium hedonic appraisal models are developed. These models allow for: (1) the computation of the influence of the identified variables on office prices (per m2); (2) the measurement of the price gaps between demand and supply according to location; and (3) the characterisation of market balances. Despite short-term adjustments between supply and demand functions, in search of market equilibrium, balances are ephemeral because they are modelled by different factors that change over time. However, these models can be adjusted and applied to different moments in time and extended to other urban contexts. As such they are able to support municipal decisions concerning land-use office location and management.
Computational and single-molecule force studies of a macro domain protein reveal a key molecular determinant for mechanical stability
Authors: Guzmán Dora L. , Randall Arlo , Baldi Pierre , Guan Zhibin
Published: January 2010

Resolving molecular determinants of mechanical stability of proteins is crucial in the rational design of advanced biomaterials for use in biomedical and nanotechnological applications. Here we present an interdisciplinary study combining bioinformatics screening, steered molecular dynamics simulations, protein engineering, and single-molecule force spectroscopy that explores the mechanical properties of a macro domain protein with mixed
α
 + 
β
topology. The unique architecture is defined by a single seven-stranded
β
-sheet in the core of the protein flanked by five
α
-helices. Unlike mechanically stable proteins studied thus far, the macro domain provides the distinct advantage of having the key load-bearing hydrogen bonds (H bonds) buried in the hydrophobic core protected from water attacks. This feature allows direct measurement of the force required to break apart the load-bearing H bonds under locally hydrophobic conditions. Steered molecular dynamics simulations predicted extremely high mechanical stability of the macro domain by using constant velocity and constant force methods. Single-molecule force spectroscopy experiments confirm the exceptional mechanical strength of the macro domain, measuring a rupture force as high as 570 pN. Furthermore, through selective deletion of shielding peptide segments, we examined the same key H bonds under hydrophilic environments in which the
β
-strands are exposed to solvent and verify that the high mechanical stability of the macro domain results from excellent shielding of the load-bearing H bonds from competing water. Our study reveals that shielding water accessibility to the load-bearing strands is a critical molecular determinant for enhancing the mechanical stability of proteins.
Role of DAB2IP in modulating epithelial-to-mesenchymal transition and prostate cancer metastasis
Authors: Xie Daxing , Gore Crystal , Liu Jun , Pong Rey-Chen , Mason Ralph , Hao Guiyang , Long Michael , Kabbani Wareef , Yu Luyang , Zhang Haifeng , Chen Hong , Sun Xiankai , Boothman David A. , Min Wang , Hsieh Jer-Tsong
Published: January 2010

A single nucleotide polymorphism in the
DAB2IP
gene is associated with risk of aggressive prostate cancer (PCa), and loss of DAB2IP expression is frequently detected in metastatic PCa. However, the functional role of DAB2IP in PCa remains unknown. Here, we show that the loss of DAB2IP expression initiates epithelial-to-mesenchymal transition (EMT), which is visualized by repression of E-cadherin and up-regulation of vimentin in both human normal prostate epithelial and prostate carcinoma cells as well as in clinical prostate-cancer specimens. Conversely, restoring DAB2IP in metastatic PCa cells reversed EMT. In DAB2IP knockout mice, prostate epithelial cells exhibited elevated mesenchymal markers, which is characteristic of EMT. Using a human prostate xenograft-mouse model, we observed that knocking down endogenous DAB2IP in human carcinoma cells led to the development of multiple lymph node and distant organ metastases. Moreover, we showed that DAB2IP functions as a scaffold protein in regulating EMT by modulating nuclear β-catenin/T-cell factor activity. These results show the mechanism of DAB2IP in EMT and suggest that assessment of DAB2IP may provide a prognostic biomarker and potential therapeutic target for PCa metastasis.
Microenvironmental modulation of asymmetric cell division in human lung cancer cells
Authors: Pine Sharon R. , Ryan Bríd M. , Varticovski Lyuba , Robles Ana I. , Harris Curtis C.
Published: January 2010

Normal tissue homeostasis is maintained through asymmetric cell divisions that produce daughter cells with differing self-renewal and differentiation potentials. Certain tumor cell subfractions can self-renew and repopulate the heterogeneous tumor bulk, suggestive of asymmetric cell division, but an equally plausible explanation is that daughter cells of a symmetric division subsequently adopt differing cell fates. Cosegregation of template DNA during mitosis is one mechanism by which cellular components are segregated asymmetrically during cell division in fibroblast, muscle, mammary, intestinal, and neural cells. Asymmetric cell division of template DNA in tumor cells has remained elusive, however. Through pulse-chase experiments with halogenated thymidine analogs, we determined that a small population of cells within human lung cancer cell lines and primary tumor cell cultures asymmetrically divided their template DNA, which could be visualized in single cells and in real time. Template DNA cosegregation was enhanced by cell–cell contact. Its frequency was density-dependent and modulated by environmental changes, including serum deprivation and hypoxia. In addition, we found that isolated CD133
+
lung cancer cells were capable of tumor cell repopulation. Strikingly, during cell division, CD133 cosegregated with the template DNA, whereas the differentiation markers prosurfactant protein-C and pan-cytokeratins were passed to the opposing daughter cell, demonstrating that segregation of template DNA correlates with lung cancer cell fate. Our results demonstrate that human lung tumor cell fate decisions may be regulated during the cell division process. The characterization and modulation of asymmetric cell division in lung cancer can provide insight into tumor initiation, growth, and maintenance.
Stromal genes discriminate preinvasive from invasive disease, predict outcome, and highlight inflammatory pathways in digestive cancers
Authors: Saadi Amel , Shannon Nicholas B. , Lao-Sirieix Pierre , O’Donovan Maria , Walker Elaine , Clemons Nicholas J. , Hardwick James S. , Zhang Chunsheng , Das Madhumita , Save Vicki , Novelli Marco , Balkwill Frances , Fitzgerald Rebecca C.
Published: January 2010

The stromal compartment is increasingly recognized to play a role in cancer. However, its role in the transition from preinvasive to invasive disease is unknown. Most gastrointestinal tumors have clearly defined premalignant stages, and Barrett’s esophagus (BE) is an ideal research model. Supervised clustering of gene expression profiles from microdissected stroma identified a gene signature that could distinguish between BE metaplasia, dysplasia, and esophageal adenocarcinoma (EAC). EAC patients overexpressing any of the five genes (
TMEPAI
,
JMY
,
TSP1
,
FAPα
, and
BCL6
) identified from this stromal signature had a significantly poorer outcome. Gene ontology analysis identified a strong inflammatory component in BE disease progression, and key pathways included cytokine–cytokine receptor interactions and TGF-β. Increased protein levels of inflammatory-related genes significantly up-regulated in EAC compared with preinvasive stages were confirmed in the stroma of independent samples, and in vitro assays confirmed functional relevance of these genes. Gene set enrichment analysis of external datasets demonstrated that the stromal signature was also relevant in the preinvasive to invasive transition of the stomach, colon, and pancreas. These data implicate inflammatory pathways in the genesis of gastrointestinal tract cancers, which can affect prognosis.
Integrative genome analysis reveals an oncomir/oncogene cluster regulating glioblastoma survivorship
Authors: Kim Hyunsoo , Huang Wei , Jiang Xiuli , Pennicooke Brenton , Park Peter J. , Johnson Mark D.
Published: January 2010

Using a multidimensional genomic data set on glioblastoma from The Cancer Genome Atlas, we identified hsa-miR-26a as a cooperating component of a frequently occurring amplicon that also contains
CDK4
and
CENTG1
, two oncogenes that regulate the RB1 and PI3 kinase/AKT pathways, respectively. By integrating DNA copy number, mRNA, microRNA, and DNA methylation data, we identified functionally relevant targets of miR-26a in glioblastoma, including PTEN, RB1, and MAP3K2/MEKK2. We demonstrate that miR-26a alone can transform cells and it promotes glioblastoma cell growth in vitro and in the mouse brain by decreasing PTEN, RB1, and MAP3K2/MEKK2 protein expression, thereby increasing AKT activation, promoting proliferation, and decreasing c-JUN N-terminal kinase-dependent apoptosis. Overexpression of miR-26a in PTEN-competent and PTEN-deficient glioblastoma cells promoted tumor growth in vivo, and it further increased growth in cells overexpressing
CDK4
or
CENTG1
. Importantly, glioblastoma patients harboring this amplification displayed markedly decreased survival. Thus, hsa-miR-26a,
CDK4
, and
CENTG1
comprise a functionally integrated oncomir/oncogene DNA cluster that promotes aggressiveness in human cancers by cooperatively targeting the RB1, PI3K/AKT, and JNK pathways.
Progression from a stem cell–like state to early differentiation in the
C. elegans
germ line
Authors: Cinquin Olivier , Crittenden Sarah L. , Morgan Dyan E. , Kimble Judith
Published: January 2010

Controls of stem cell maintenance and early differentiation are known in several systems. However, the progression from stem cell self-renewal to overt signs of early differentiation is a poorly understood but important problem in stem cell biology. The
Caenorhabditis elegans
germ line provides a genetically defined model for studying that progression. In this system, a single-celled mesenchymal niche, the distal tip cell (DTC), employs GLP-1/Notch signaling and an RNA regulatory network to balance self-renewal and early differentiation within the “mitotic region,” which continuously self-renews while generating new gametes. Here, we investigate germ cells in the mitotic region for their capacity to differentiate and their state of maturation. Two distinct pools emerge. The “distal pool” is maintained by the DTC in an essentially uniform and immature or “stem cell–like” state; the “proximal pool,” by contrast, contains cells that are maturing toward early differentiation and are likely transit-amplifying cells. A rough estimate of pool sizes is 30–70 germ cells in the distal immature pool and ≈150 in the proximal transit-amplifying pool. We present a simple model for how the network underlying the switch between self-renewal and early differentiation may be acting in these two pools. According to our model, the self-renewal mode of the network maintains the distal pool in an immature state, whereas the transition between self-renewal and early differentiation modes of the network underlies the graded maturation of germ cells in the proximal pool. We discuss implications of this model for controls of stem cells more broadly.
Epigenetic control of the variable expression of aPlasmodium falciparumreceptor protein for erythrocyte invasion
Authors: Jiang Lubin , López-Barragán María José , Jiang Hongying , Mu Jianbing , Gaur Deepak , Zhao Keji , Felsenfeld Gary , Miller Louis H.
Published: January 2010

Plasmodium falciparumcan invade erythrocytes by redundant receptors, some of which have variable expression. AP. falciparumclone Dd2 requiring erythrocyte sialic acid for invasion can be switched to a sialic acid-independent progeny clone Dd2NM by growing the Dd2 clone with neuraminidase-treated erythrocytes. TheRH4gene is transcriptionally up-regulated in Dd2NM compared to Dd2, despite the absence of DNA changes in and around the gene. We determined the epigenetic modifications around the transcription start site (TSS) at the time of expression ofRH4in Dd2NM (44 h) and at an earlier time whenRH4is not expressed (24 h). At 44 h, the occupancy of the +1 nucleosome site downstream of the TSS of the activeRH4gene in Dd2NM was markedly reduced compared to Dd2; no difference was observed at 24 h. At 44 h, histone modifications associated with up-regulation were positively correlated to the activeRH4gene of Dd2NM compared to Dd2; no differences were observed at 24 h. Histone H3K9 trimethylation (a marker for silencing) was higher in Dd2 than Dd2NM along the 5′-UTRs of theRH4gene at both 44 and 24 h. Our data indicate that the failure of Dd2 to express the sialic acid-independent invasion receptor geneRH4is associated with the epigenetic silencing mark H3K9 trimethylation present throughout the cycle.
Plant homologs of the
Plasmodium falciparum
chloroquine-resistance transporter,
Pf
CRT, are required for glutathione homeostasis and stress responses
Authors: Maughan Spencer C. , Pasternak Maciej , Cairns Narelle , Kiddle Guy , Brach Thorsten , Jarvis Renee , Haas Florian , Nieuwland Jeroen , Lim Benson , Müller Christopher , Salcedo-Sora Enrique , Kruse Cordula , Orsel Mathilde , Hell Rüdiger , Miller Anthony J. , Bray Patrick , Foyer Christine H. , Murray James A.H. , Meyer Andreas J. , Cobbett Christopher S.
Published: January 2010

In
Arabidopsis thaliana
, biosynthesis of the essential thiol antioxidant, glutathione (GSH), is plastid-regulated, but many GSH functions, including heavy metal detoxification and plant defense activation, depend on cytosolic GSH. This finding suggests that plastid and cytosol thiol pools are closely integrated and we show that in Arabidopsis this integration requires a family of three plastid thiol transporters homologous to the
Plasmodium falciparum
chloroquine-resistance transporter,
Pf
CRT. Arabidopsis mutants lacking these transporters are heavy metal-sensitive, GSH-deficient, and hypersensitive to
Phytophthora
infection, confirming a direct requirement for correct GSH homeostasis in defense responses. Compartment-specific measurements of the glutathione redox potential using redox-sensitive GFP showed that knockout of the entire transporter family resulted in a more oxidized glutathione redox potential in the cytosol, but not in the plastids, indicating the GSH-deficient phenotype is restricted to the cytosolic compartment. Expression of the transporters in
Xenopus
oocytes confirmed that each can mediate GSH uptake. We conclude that these transporters play a significant role in regulating GSH levels and the redox potential of the cytosol.
Chromosome arm length and nuclear constraints determine the dynamic relationship of yeast subtelomeres
Authors: Therizols Pierre , Duong Tarn , Dujon Bernard , Zimmer Christophe , Fabre Emmanuelle
Published: January 2010

Physical interactions between distinct chromosomal genomic loci are important for genomic functions including recombination and gene expression, but the mechanisms by which these interactions occur remain obscure. Using telomeric association as a model system, we analyzed here the in vivo organization of chromosome ends of haploid yeast cells during interphase. We separately labeled most of the 32 subtelomeres and analyzed their positions both in nuclear space and relative to three representative reference subtelomeres by high-throughput 3D microscopy and image processing. We show that subtelomeres are positioned nonrandomly at the nuclear periphery, depending on the genomic size of their chromosome arm, centromere attachment to the microtubule organizing center (spindle pole body, SPB), and the volume of the nucleolus. The distance of subtelomeres to the SPB increases consistently with chromosome arm length up to ≈300 kb; for larger arms the influence of chromosome arm length is weaker, but the effect of the nucleolar volume is stronger. Distances between pairs of subtelomeres also exhibit arm-length dependence and suggest, together with dynamic tracking experiments, that potential associations between subtelomeres are unexpectedly infrequent and transient. Our results suggest that interactions between subtelomeres are nonspecific and instead governed by physical constraints, including chromosome structure, attachment to the SPB, and nuclear crowding.