bluuebunny/crossref_metadata_2025 huggingface dataset:
Looking at European Sports from an Eastern European Perspective: Football in the Multi-ethnic Polish Territories
Authors: Hilbrenner Anke , Lenz Britta
Published: August 2011

Until recently, sports history has largely neglected Eastern Europe. Yet new research has shown that historians need to embrace a perspective from the periphery towards the centre, and reach beyond the paradigms of modernization, Sovietization, and the nation-state if Europe's sporting culture is to be fully understood. Focusing primarily on Poland, this article outlines three features peculiar to the region. First, it stresses the importance of trans-national spaces and networks as well as European sub-regions. Missing out on the initial phase of sport's internationalization due to lack of independence, the development of Polish sport was regionally distinct. Sports flourished in Habsburg-ruled Galicia (in Cracow and Lodz especially) under relatively liberal political authorities, but developed more slowly and under different influences elsewhere. Second, the prominence of rural Galicia, inhabited by traditional groups such as Ukrainian peasants or Chassidic Jews, shows that Polish sport did not evolve in line with modernization and industrialization. The relatively slow diffusion of sport in industrial centres such as Warsaw or Silesia contradicts the paradigm of modernization and the notion of East European backwardness. Third, sport history sheds light on phenomena such as multi-ethnicity, migration, integration or disintegration.
Rule of law and the size of government
Authors: HOLCOMBE RANDALL G. , RODET CORTNEY S.
Published: August 2011

If those with political power benefit from corrupt institutions, rulers might not adopt the rule of law so the ruling class can command a larger share of a smaller pie. An empirical analysis reveals that the size of government is larger in those countries that enforce the rule of law. If government expenditures provide some measure of the ability of the ruling class to command resources, this suggests that those with political power could benefit from imposing a fairer and more objective legal structure. Another conjecture is that those in power maintain corrupt governments to pay off their supporters and enhance their ability to remain in power. However, the rule of law is also positively associated with political stability, so better enforcement of the rule of law also enhances the ability of incumbent governments to remain in power.
Ressourcenorientierte Diagnostik des Sozialverhaltens in der Schule
Authors: Schreyer-Mehlhop Ina , Petermann Franz , Siener Cathrin , Petermann Ulrike
Published: August 2011

Mit der Lehrereinschätzliste für Sozial- und Lernverhalten (LSL; Petermann & Petermann, 2006 ) können Lehrkräfte das schulbezogene Sozial- und Lernverhalten von Schülern im Alter von sechs bis 19 Jahren differenziert bewerten. Die vorliegende Arbeit ergänzt die bislang verfügbaren Ergebnisse zur Aussagekraft der LSL und untersucht speziell die Zuverlässigkeit der sechs Skalen zum Sozialverhalten. In die Stichprobe gingen insgesamt 97 Schüler im Alter von elf bis 13 Jahren ein, die die fünfte Klasse einer Gesamtschule besuchten. Für alle Schüler wurden von den Lehrkräften sowohl Daten zur LSL als auch zum Strengths and Difficulties Questionnaire (SDQ; Goodman, 1997 ) erhoben. Korrelationsanalysen verdeutlichen die Zusammenhänge zwischen der LSL und dem SDQ. Diskriminanzanalysen illustrieren, welche LSL-Skalen in einem multivariaten Modell gut in der Lage sind, zwischen verhaltensauffälligen und unauffälligen Kindern sowie Kindern mit hohen und niedrigen sozial-emotionalen Kompetenzen zu unterscheiden. Die Ergebnisse der Korrelations- und Diskriminanzanalysen unterstreichen die Validität der LSL.
Förderung sozial-emotionaler Kompetenz in der frühen Kindheit
Authors: Wiedebusch Silvia , Petermann Franz
Published: August 2011

Die frühe Förderung sozial-emotionaler Fertigkeiten als präventive Maßnahme zur Unterstützung dieses zentralen Entwicklungsbereiches zeigt kurz- und längerfristige Auswirkungen auf ein positives Sozialverhalten, die Lernmotivation und den Schulerfolg sowie die physische und psychische Gesundheit von Kindern. Es werden strukturierte Förderprogramme für verschiedene Ziel- und Altersgruppen, nämlich Bezugspersonen von Klein-, Vorschul- und Grundschulkindern vorgestellt und dabei Möglichkeiten und Grenzen der Förderung aufgezeigt. Demnach profitieren vor allem Risikokinder von einer frühen Förderung sozial-emotionaler Kompetenz. Schließlich werden auf der Grundlage von Evaluationsergebnissen Empfehlungen für den Einsatz von Entwicklungsscreenings und Fördermaßnahmen in (früh-)pädagogischen Einrichtungen ausgesprochen und ein Mehr-Ebenen-Modell vorgestellt, mit dem eine individuelle und bedarfsgerechte Förderplanung ermöglicht wird.
Förderung sozial-emotionaler Kompetenz im Kindergarten
Authors: Wadepohl Heike , Koglin Ute , Vonderlin Eva , Petermann Franz
Published: August 2011

Die vorliegende Studie untersucht die Wirksamkeit eines präventiven Verhaltenstrainings zur Förderung sozial-emotionaler Kompetenz. 127 Kindergartenkinder nahmen am Verhaltenstraining teil und wurden mit einer Kontrollgruppe (n = 129) vor und nach dem Training anhand der Erzieherinnenurteile verglichen. Anschließend wurden die differenziellen Trainingseffekte für eine Risikokindergruppe mit auffälligem Sozialverhalten untersucht. Für die Gesamtgruppe konnten positive Effekte für den Aufbau der sozial-emotionalen Kompetenz erzielt werden. Deutlich geringer war die Wirkung des Trainings auf die Verhaltensprobleme der Kinder. Für die Risikokinder konnten jedoch gute Effekte im Bezug auf beide Bereiche festgestellt werden. Aufgrund der gut integrierbaren und kostengünstigen Durchführbarkeit sowie den Ergebnissen im Bereich der Kompetenzförderung kann das hier evaluierte Training als universelles Präventionsprogramm empfohlen werden.
Langzeiteffekte einer kindergartenbasierten Förderung der phonologischen Bewusstheit
Authors: Rißling Julia-Katharina , Metz Dorothee , Melzer Jessica , Petermann Franz
Published: August 2011

Es wird untersucht, ob Kinder langfristig von den Trainingsprogrammen zur Förderung der phonologischen Bewusstheit Lobo vom Globo profitieren, so dass Lese- und Rechtschreibprobleme vermieden werden können. Berichtet werden die Ergebnisse von 89 Zweitklässlern (Fördergruppe Kindergarten: n = 24; kombinierte Gruppe: n = 35; Vergleichsgruppe: n = 30), die mit einem Leseverständnistest und einem Verfahren zur Überprüfung der Rechtschreibleistung erfasst wurden. Die Ergebnisse zeigen einen Vorteil der im Kindergarten geförderten Kinder. Die Kinder, die an einer kombinierten Förderung in Kindergarten und Grundschule teilnahmen, erzielen im Leseverständnis und in der Rechtschreibung besonders optimale Ergebnisse.
Study of the Impact of a Gastroplasty on the Self-Image Through the Rorschach
Authors: Marsden Eric , Michel Aude , Mormont Christian
Published: August 2011

Depuis plus de cinquante ans, différentes études ont révélé que les personnes souffrant d’obésité morbide possédaient une image du corps et une image de soi dépréciée.

L’objectif de notre recherche est d’observer l’évolution de cette image de soi chez des personnes perdant rapidement du poids suite à une gastroplastie en analysant les sept différentes variables qui constituent le cluster perception de soi du Système Intégré d’Exner.

Pour ce faire, nous avons administré le Rorschach à trois reprises auprès de patients sollicitant une gastroplastie: le premier testing a eu lieu lors de leur hospitalisation, la veille de leur opération; les deuxièmes et troisièmes testings ont eu lieu après une période de trois et dix mois, le plus souvent au domicile du patient ou lors d’une visite de contrôle chez le chirurgien. Notre population se compose de 30 patients âgés de 20 à 54 ans (avec une moyenne de 33 ans et 6 mois) et dont le poids variait de 94 à 144 kilogrammes (avec une moyenne de 115,7 kilogrammes) avant leur opération.

L’échantillon observé présente un nombre élevé et grandissant d’ambiéquaux (passant de 56% à 73%) et un faible pourcentage d’extratensifs (1%) disparaissant en 10 mois. De plus 4 sujets au style indéterminé (M = 0) se révèlent être des ambiéquaux en perdant du poids comme si leur activité idéationnelle se trouvait “débloquée” un fois que l’obésité tend à disparaître.

Le pourcentage de personnes présentant un DEPI positif passe de 10% à 23% en dix mois. L’hypothèse est que l’obésité possédait une valeur défensive qui disparaît parallèlement à la perte de poids expliquant cette augmentation de sujets au DEPI positif.

Enfin, 60% de la population présentent un CDI positif toujours après dix mois d’amaigrissement. L’hypothèse est que des difficultés sociales peuvent entraîner une obésité par un processus de régression orale. Lorsque l’obésité et les comportements de nourrissage disparaissent, les difficultés sociales restent présentes.

La centration sur soi est négative avant l’opération. La qualité de cet intérêt pour soi peut être améliorée selon certains facteurs: l’histoire de leur obésité, le type d’opération et le suivi postopératoire. (a) Plus l’obésité est ancienne, plus l’image de soi s’en trouve affectée; par ailleurs, les sujets ayant développé une obésité réactionnelle présente une composante narcissique importante. (b) La cicatrice que laisse l’opération V.B.G. (vertical banded gastroplasty) est un pôle de centration sur soi qui permet au sujet de se focaliser sur son corps. (c) L’accompagnement postopératoire facilite l’assimilation de la métamorphose corporelle et valorise l’image de soi.

Il semble que l’on puisse retenir l’hypothèse selon laquelle la gastroplastie entraîne des modification de l’image du corps et de l’image de soi chez des personnes sévèrement obèses.
The development of a simple basal area increment model
Authors: Kindermann Georg Erich
Published: August 2011

In most cases forest practice in Austria use yield tables to predict the growth of their forests. Common yield tables show the increment of pure even-aged stands which are treated in a way the table developer recommends. The usage of these tables in stands which are either uneven-aged, mixed or treated in another way, may lead to inaccurate predictions. To avoid these problems, forest growth models have been developed. Until now they are not widely used in Austria. One reason may be, that most of the models need some input parameters which are usually not gathered by companies. In this work a basal area increment per hectare model has been developed which is based on the input parameters: diameter at breast height, height to diameter ratio, top height at age 100 years and a selection out of several simple competition indices (growing space, basal area of larger trees, competing basal area, crown cross sectional area, crown competition factor, d/dg, d-dg, basal area and stand density index) which are distance independent. The model parametrization was done with seven different statistical methods (linear regression, linear mixed effect model, resistant linear regression, local polynomial regression, lazy learning model, random forest model and neural network model). By using only few input-parameters it should be possible to parametrize this model for many local areas by using inventory data sets of the specific region. The model works in pure and mixed stands of spruce and beech at the Rosaliengebirge. The observed average diameter increment per 5 years is 18.1 mm for spruce and 21.1 mm for beech. The average difference of the predicted and observed diameter-increment on a validation data-set is 0.3 mm for spruce and -0.3 mm for beech within 5 years and the estimated additional spread caused by the model is +-4.5 mm/5 years for spruce and +-4.0 mm/5 years for beech.
An Evaluation of Visual and Textual Network Analysis Tools
Authors: Goodall John R
Published: August 2011

User testing is an integral component of user-centered design, but has only rarely been applied to visualization for cyber security applications. This article presents the results of a comparative evaluation between a visualization-based application and a more traditional, table-based application for analyzing computer network packet captures. We conducted this evaluation as part of the user-centered design process. Participants performed both structured, well-defined tasks and exploratory, open-ended tasks with both tools. We measured accuracy and efficiency for the well-defined tasks, number of insights was measured for exploratory tasks and user perceptions were recorded for each tool. The results of this evaluation demonstrated that users performed significantly more accurately in the well-defined tasks, discovered a higher number of insights and demonstrated a clear preference for the visualization tool. The study design presented may be useful for future researchers performing user testing on visualization for cyber security applications.
Field evaporation mechanism of bulk oxides under ultra fast laser illumination
Authors: Vella A. , Mazumder B. , Da Costa G. , Deconihout B.
Published: August 2011

The controlled field evaporation of single atoms from an oxide surface assisted by ultra fast laser pulses has recently been demonstrated. When UV light is used, a photoionization mechanism was proposed. However, experimental results observed when the laser intensity and wavelength are changed cannot be explained by this mechanism. Instead, a thermal assisted evaporation mechanism characterized by two evaporation times is proposed. The fast and slow evaporation rates are associated to two cooling processes inside the tip sample. Experiments are carried out on TiO2 and MgO field emitter tips to check the dependence of the evaporation process on structural properties of the oxide. A good agreement between the predictions of our model and the experimental data is found.
Characteristic non-Debye heat capacity formula applied to GaN and ZnO
Authors: Pässler R.
Published: August 2011

Characteristic non-Debye behaviors of heat capacity data, Cp(T), which are mainly manifested in the form of non-monotonic dependences (maxima) of the respective Cp(T)/T3 curves in the cryogenic region, are described by means of an unprecedented interpolation formula. Least mean square fittings of duly comprehensive Cp(T) data sets available for GaN and ZnO show excellent agreement, from the liquid-helium-hydrogen region up to high temperatures. We show that, in contrast to misleading suggestions made in some recent thermo-physical papers, Debye’s heat capacity formula used under the presumption of a fixed Debye temperature is clearly incapable of providing reasonable numerical simulations of measured Cp(T) dependences.
Growth of Si-doped GaInP on Ge-on-Si substrates and its photoluminescence characteristics
Authors: Yang Changjae , Lee Sangsoo , Wook Shin Keun , Oh Sewoung , Park Jinsub , Kim Chang-Zoo , Park Won-Kyu , Ha Seung-kyu , Jun Choi Won , Yoon Euijoon
Published: August 2011

Optical properties of Si-doped GaInP grown on Ge-on-Si substrates were investigated using photoluminescence (PL). Similar to spontaneously ordered GaInP, two peaks were observed around 1.74 and 1.85 eV at 19 K; however, no satellite peaks were observed in the selected-area diffraction pattern. Based on temperature-dependent PL, the peak at 1.74 eV was attributed to the donor–acceptor pair transition caused by the amphoteric characteristics of Si and/or Ge from the dopant and/or substrate. In addition, the S-shape in the temperature dependence of the 1.85 eV peak was attributed to the interaction of the donor levels with the conduction band of GaInP.
Over-reflection of slow magnetosonic waves by homogeneous shear flow: Analytical solution
Authors: Dimitrov Z. D. , Maneva Y. G. , Hristov T. S. , Mishonov T. M.
Published: August 2011

We have analyzed the amplification of slow magnetosonic (or pseudo-Alfvénic) waves (SMW) in incompressible shear flow. As found here, the amplification depends on the component of the wave-vector perpendicular to the direction of the shear flow. Earlier numerical results are consistent with the general analytic solution for the linearized magnetohydrodynamic equations, derived here for the model case of pure homogeneous shear (without Coriolis force). An asymptotically exact analytical formula for the amplification coefficient is derived for the case when the amplification is sufficiently large.
Flights in a pseudo-chaotic system
Authors: Lowenstein J. H. , Vivaldi F.
Published: August 2011

We consider the problem of transport in a one-parameter family of piecewise rotations of the torus, for rotation number approaching 1/4. This is a zero-entropy system which in this limit exhibits a divided phase space, with island chains immersed in a “pseudo-chaotic” region. We identify a novel mechanism for long-range transport, namely the adiabatic destruction of accelerator-mode islands. This process originates from the approximate translational invariance of the phase space and leads to long flights of linear motion, for a significant measure of initial conditions. We show that the asymptotic probability distribution of the flight lengths is determined by the geometric properties of a partition of the accelerator-mode island associated with the flight. We establish the existence of flights travelling distances of order O(1) in phase space. We provide evidence for the existence of a scattering process that connects flights travelling in opposite directions.
Blue photoluminescence and Auger recombination of carriers in SrTiO3 nanoparticles
Authors: Yamada Yasuhiro , Suzuki Keigo , Kanemitsu Yoshihiko
Published: August 2011

We studied photoluminescence (PL) spectrum and dynamics of SrTiO3 nanoparticles. A broad blue PL band is observed at around 2.9 eV in nanoparticle thin films. The excitation-density dependence of the blue PL intensity indicates that nonradiative Auger recombination dominates the carrier recombination process under strong photoexcitation. The intrinsic Auger recombination rate in SrTiO3 nanoparticles is much larger than that of SrTiO3 bulk crystals. The origin of enhanced Auger recombination in SrTiO3 nanoparticles is discussed.
On the high-field transport and its temperature dependence in deca-nanometer fully depleted silicon-on-insulator field-effect-transistor
Authors: Kobayashi Masaharu , Cai Jin , Haensch Wilfried
Published: August 2011

Low-temperature characterization has been performed on fully depleted silicon-on-insulator (FDSOI) field-effect-transistor (FET) with gate length (Lg) down to 25 nm to clarify transport mechanisms that determine device performance in deca-nanometer scale. Linear drain current of FDSOI FET follows Lg−1 scaling down to 25 nm Lg, where mobility dominates, while saturation drain current largely deviates from Lg−1 scaling. Temperature dependence of effective source velocity at high drain voltage (Vds) is weaker than that at low Vds in short Lg and is consistent with that of saturation velocity. Drift velocity measurement revealed velocity overshooting behavior at high lateral field, indicating further Lg scaling benefit.
Reflectance spectrum of plasmon waveguide interband cascade lasers and observation of the Berreman effect
Authors: Hinkey Robert T. , Tian Zhaobing , Yang Rui Q. , Mishima Tetsuya D. , Santos Michael B.
Published: August 2011

Noninvasive infrared reflectance measurements have been explored as a method for studying the optical properties of Si-doped cladding layers of plasmon waveguide interband cascade lasers. Measurements and theoretical simulations of the reflectance spectra were carried out on both the laser structures themselves, as well as highly doped InAs films grown on GaAs substrates. We have found that there is a sharp drop in the signal of the reflectance spectrum for p-polarized light oscillating near the plasma frequency. This is a manifestation of the so-called Berreman effect, which occurs at frequencies where the dielectric function approaches zero. This is distinct from the plasma edge feature seen in the reflectance spectrum of thick samples. The plasma frequencies of the highly doped layers were obtained by identifying the Berreman feature in the measured spectrum and fitting the spectrum to a modeled curve. Using a model for the effective mass, we were able to obtain measurements of the conduction electron concentration (in a range from 1018 to 1019 cm−3) in the waveguide cladding layers with values that were in good agreement with those found using Hall effect and SIMS measurements. The reflectance data was effectively used to achieve better calibration of the Si-doping during the growth of the n++-type InAs layers in the plasmon waveguide laser structures.
Free standing graphene-diamond hybrid films and their electron emission properties
Authors: Varshney Deepak , Venkateswara Rao Chitturi , Guinel Maxime J.-F. , Ishikawa Yasuyuki , Weiner Brad R. , Morell Gerardo
Published: August 2011

Free standing graphene-diamond hybrid films have been fabricated using saturated hydrocarbon polymers as seeding material by hot filament chemical vapor deposition technique. The films are characterized with x-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and electron energy loss spectroscopy (EELS). The XRD shows the characteristic diffraction peaks of both diamond and graphene. The Raman spectrum shows the characteristic band of diamond at 1332 cm−1 and D, G, and 2D bands of graphene at 1349, 1592, and 2687 cm−1, respectively. Both SEM and TEM depict the presence of diamond and graphene in the films. The EELS recorded in the carbon K-edge region also shows the signature peaks of diamond and graphene. The free standing hybrid films exhibit a remarkably low turn-on field of about 2.4 V/μm and a high emission current density of 0.1 mA/cm2. Furthermore, emission currents are stable over the period of 7 days. The superior field emission characteristics of the free standing graphene-diamond hybrid films are attributed to the heat sink capability of diamond and high electrical conductivity of graphene.
2 + 1 KdV(N) equations
Authors: Gürses Metin , Pekcan Aslı
Published: August 2011

We present some nonlinear partial differential equations in 2 + 1-dimensions derived from the KdV equation and its symmetries. We show that all these equations have the same 3-soliton solution structures. The only difference in these solutions are the dispersion relations. We also show that they possess the Painlevé property.
Highly stable Al-doped ZnO transparent conductors using an oxidized ultrathin metal capping layer at its percolation thickness
Authors: Chen T. L. , Ghosh D. S. , Krautz D. , Cheylan S. , Pruneri V.
Published: August 2011

Metal capping layer can be used to enhance the physical properties of thin films. We propose a transparent conductor structure made of Al-doped ZnO (AZO) and an oxidized Ni capping layer, the latter with a thickness in proximity of its percolation threshold (2.5 nm). The capping layer inhibits the penetration of oxygen and water into the AZO’s grain boundaries thus significantly increasing the stability of the combined structure, as it is shown by its resistance in damp heat testing at 95 °C and 95% humidity. In addition, the oxidized Ni capping layer increases the performance of AZO transparent anodes in organic light emitting diodes by producing efficiencies as high as those of indium-tin-oxide based devices.
Effects of surface morphology on retention loss of ferroelectric domains in poly(vinylidenefluoride-co-trifluoroethylene) thin films
Authors: Choi Hyunwoo , Hong Seungbum , Sung Tae-Hyun , No Kwangsoo
Published: August 2011

Effects of surface morphology on the retention loss of ferroelectric domains of poly(vinylidenefluoride-co-trifluoroethylene) thin films were investigated using piezoresponse force microscopy. We found that the retention loss occurred by nucleation of opposite domains at the regions with morphological gradients between 0.079 and 0.146. In addition, we observed collective decreases in piezoresponse amplitude of the opposite domains after 0.8 × 106 s, although each reversed domain showed different growth rate as evidenced by different threshold time for phase reversal. These results suggest that the surface morphology has a strong influence in determining the nucleation and growth kinetics by which the retention loss occurs.
Polyamine catabolism contributes to enterotoxigenic
Bacteroides fragilis
-induced colon tumorigenesis
Authors: Goodwin Andrew C. , Shields Christina E. Destefano , Wu Shaoguang , Huso David L. , Wu XinQun , Murray-Stewart Tracy R. , Hacker-Prietz Amy , Rabizadeh Shervin , Woster Patrick M. , Sears Cynthia L. , Casero Robert A.
Published: August 2011

It is estimated that the etiology of 20–30% of epithelial cancers is directly associated with inflammation, although the direct molecular events linking inflammation and carcinogenesis are poorly defined. In the context of gastrointestinal disease, the bacterium enterotoxigenic
Bacteroides fragilis
(ETBF) is a significant source of chronic inflammation and has been implicated as a risk factor for colorectal cancer. Spermine oxidase (SMO) is a polyamine catabolic enzyme that is highly inducible by inflammatory stimuli resulting in increased reactive oxygen species (ROS) and DNA damage. We now demonstrate that purified
B. fragilis
toxin (BFT) up-regulates SMO in HT29/c1 and T84 colonic epithelial cells, resulting in SMO-dependent generation of ROS and induction of γ-H2A.x, a marker of DNA damage. Further, ETBF-induced colitis in C57BL/6 mice is associated with increased SMO expression and treatment of mice with an inhibitor of polyamine catabolism,
N
1
,
N
4
-bis(2,3-butandienyl)-1,4-butanediamine (MDL 72527), significantly reduces ETBF-induced chronic inflammation and proliferation. Most importantly, in the multiple intestinal neoplasia (Min) mouse model, treatment with MDL 72527 reduces ETBF-induced colon tumorigenesis by 69% (
P
< 0.001). The results of these studies indicate that SMO is a source of bacteria-induced ROS directly associated with tumorigenesis and could serve as a unique target for chemoprevention.
Intramolecular signal transmission in a tetrameric repressor of the IclR family
Authors: Fillet Sandy , Krell Tino , Morel Bertrand , Lu Duo , Zhang Xiaodong , Ramos Juan L.
Published: August 2011

Members of the IclR family control bacterial genes involved in a number of physiological processes. The IclR-family member TtgV crystallizes as a tetramer, with each TtgV monomer consisting of two domains—a DNA binding domain and an effector recognition domain, which are interconnected by an extended α-helix. When bound to DNA, a kink is introduced so that the extended helix is split in two α-helices (helix-4 and -5). Differential scanning calorimetry studies revealed that TtgV unfolds in a single event, suggesting that the two domains unfold cooperatively. When mutations are introduced in helix-5 that disrupt interactions between Arg98 and Glu102, the thermal unfolding of the TtgV domains becomes uncoupled without compromising effector binding. Two of these mutants (TtgVE102R and TtgVE102A) showed impaired release from target DNA, suggesting that these mutations alter signal transmission. By combining various mutants, we found that the mutations in the connecting α-helix exhibited a dominant effect over mutations in DNA binding and effector binding domains. We propose a model in which the loss of cooperativity of unfolding of TtgV reflects perturbed interdomain communication, and that the transition from the continuous to discontinuous helix may mediate interdomain communication necessary for the proper functioning of TtgV.
Differential radial capillary action of ligand assay for high-throughput detection of protein-metabolite interactions
Authors: Roelofs Kevin G. , Wang Jingxin , Sintim Herman O. , Lee Vincent T.
Published: August 2011

Interactions of proteins with low-molecular-weight ligands, such as metabolites, cofactors, and allosteric regulators, are important determinants of metabolism, gene regulation, and cellular homeostasis. Pharmaceuticals often target these interactions to interfere with regulatory pathways. We have developed a rapid, precise, and high-throughput method for quantitatively measuring protein-ligand interactions without the need to purify the protein when performed in cells with low background activity. This method, differential radial capillary action of ligand assay (DRaCALA), is based on the ability of dry nitrocellulose to separate the free ligand from bound protein–ligand complexes. Nitrocellulose sequesters proteins and bound ligand at the site of application, whereas free ligand is mobilized by bulk movement of the solvent through capillary action. We show here that DRaCALA allows detection of specific interactions between three nucleotides and their cognate binding proteins. DRaCALA allows quantitative measurement of the dissociation constant and the dissociation rate. Furthermore, DRaCALA can detect the expression of a cyclic-di-GMP (cdiGMP)-binding protein in whole-cell lysates of
Escherichia coli
, demonstrating the power of the method to bypass the prerequisite for protein purification. We have used DRaCALA to investigate cdiGMP signaling in 54 bacterial species from 37 genera and 7 eukaryotic species. These studies revealed the presence of potential cdiGMP-binding proteins in 21 species of bacteria, including 4 unsequenced species. The ease of obtaining metabolite-protein interaction data using the DRaCALA assay will facilitate rapid identification of protein-metabolite and protein-pharmaceutical interactions in a systematic and comprehensive approach.
Inflammasome is a central player in the induction of obesity and insulin resistance
Authors: Stienstra Rinke , van Diepen Janna A. , Tack Cees J. , Zaki Md. Hasan , van de Veerdonk Frank L. , Perera Deshani , Neale Geoffrey A. , Hooiveld Guido J. , Hijmans Anneke , Vroegrijk Irene , van den Berg Sjoerd , Romijn Johannes , Rensen Patrick C. N. , Joosten Leo A. B. , Netea Mihai G. , Kanneganti Thirumala-Devi
Published: August 2011

Inflammation plays a key role in the pathogenesis of obesity. Chronic overfeeding leads to macrophage infiltration in the adipose tissue, resulting in proinflammatory cytokine production. Both microbial and endogenous danger signals trigger assembly of the intracellular innate immune sensor Nlrp3, resulting in caspase-1 activation and production of proinflammatory cytokines IL-1β and IL-18. Here, we showed that mice deficient in Nlrp3, apoptosis-associated speck-like protein, and caspase-1 were resistant to the development of high-fat diet-induced obesity, which correlated with protection from obesity-induced insulin resistance. Furthermore, hepatic triglyceride content, adipocyte size, and macrophage infiltration in adipose tissue were all reduced in mice deficient in inflammasome components. Monocyte chemoattractant protein (MCP)-1 is a key molecule that mediates macrophage infiltration. Indeed, defective inflammasome activation was associated with reduced MCP-1 production in adipose tissue. Furthermore, plasma leptin and resistin that affect energy use and insulin sensitivity were also changed by inflammasome-deficiency. Detailed metabolic and molecular phenotyping demonstrated that the inflammasome controls energy expenditure and adipogenic gene expression during chronic overfeeding. These findings reveal a critical function of the inflammasome in obesity and insulin resistance, and suggest inhibition of the inflammasome as a potential therapeutic strategy.
Complementary roles of Fas-associated death domain (FADD) and receptor interacting protein kinase-3 (RIPK3) in T-cell homeostasis and antiviral immunity
Authors: Lu Jennifer V. , Weist Brian M. , van Raam Bram J. , Marro Brett S. , Nguyen Long V. , Srinivas Prathna , Bell Bryan D. , Luhrs Keith A. , Lane Thomas E. , Salvesen Guy S. , Walsh Craig M.
Published: August 2011

Caspase-8 (casp8) is required for extrinsic apoptosis, and mice deficient in casp8 fail to develop and die in utero while ultimately failing to maintain the proliferation of T cells, B cells, and a host of other cell types. Paradoxically, these failures are not caused by a defect in apoptosis, but by a presumed proliferative function of this protease. Indeed, following mitogenic stimulation, T cells lacking casp8 or its adaptor protein FADD (Fas-associated death domain protein) develop a hyperautophagic morphology, and die a programmed necrosis-like death process termed necroptosis. Recent studies have demonstrated that receptor-interacting protein kinases (RIPKs) RIPK1 and RIPK3 together facilitate TNF-induced necroptosis, but the precise role of RIPKs in the demise of T cells lacking FADD or casp8 activity is unknown. Here we demonstrate that RIPK3 and FADD have opposing and complementary roles in promoting T-cell clonal expansion and homeostasis. We show that the defective proliferation of T cells bearing an interfering form of FADD (FADDdd) is rescued by crossing with RIPK3
−/−
mice, although such rescue ultimately leads to lymphadenopathy. Enhanced recovery of these double-mutant T cells following stimulation demonstrates that FADD, casp8, and RIPK3 are all essential for clonal expansion, contraction, and antiviral responses. Finally, we demonstrate that caspase-mediated cleavage of RIPK1-containing necrosis inducing complexes (necrosomes) is sufficient to prevent necroptosis in the face of death receptor signaling. These studies highlight the “two-faced” nature of casp8 activity, promoting clonal expansion in some situations and apoptotic demise in others.
Lack of confidence in approximate Bayesian computation model choice
Authors: Robert Christian P. , Cornuet Jean-Marie , Marin Jean-Michel , Pillai Natesh S.
Published: August 2011

Approximate Bayesian computation (ABC) have become an essential tool for the analysis of complex stochastic models. Grelaud et al. [(2009)
Bayesian Anal
3:427–442] advocated the use of ABC for model choice in the specific case of Gibbs random fields, relying on an intermodel sufficiency property to show that the approximation was legitimate. We implemented ABC model choice in a wide range of phylogenetic models in the Do It Yourself-ABC (DIY-ABC) software [Cornuet et al. (2008)
Bioinformatics
24:2713–2719]. We now present arguments as to why the theoretical arguments for ABC model choice are missing, because the algorithm involves an unknown loss of information induced by the use of insufficient summary statistics. The approximation error of the posterior probabilities of the models under comparison may thus be unrelated with the computational effort spent in running an ABC algorithm. We then conclude that additional empirical verifications of the performances of the ABC procedure as those available in DIY-ABC are necessary to conduct model choice.
Ingestion of
Lactobacillus
strain regulates emotional behavior and central GABA receptor expression in a mouse via the vagus nerve
Authors: Bravo Javier A. , Forsythe Paul , Chew Marianne V. , Escaravage Emily , Savignac Hélène M. , Dinan Timothy G. , Bienenstock John , Cryan John F.
Published: August 2011

There is increasing, but largely indirect, evidence pointing to an effect of commensal gut microbiota on the central nervous system (CNS). However, it is unknown whether lactic acid bacteria such as
Lactobacillus rhamnosus
could have a direct effect on neurotransmitter receptors in the CNS in normal, healthy animals. GABA is the main CNS inhibitory neurotransmitter and is significantly involved in regulating many physiological and psychological processes. Alterations in central GABA receptor expression are implicated in the pathogenesis of anxiety and depression, which are highly comorbid with functional bowel disorders. In this work, we show that chronic treatment with
L. rhamnosus
(
JB-1
) induced region-dependent alterations in GABA
B1b
mRNA in the brain with increases in cortical regions (cingulate and prelimbic) and concomitant reductions in expression in the hippocampus, amygdala, and
locus coeruleus
, in comparison with control-fed mice. In addition,
L. rhamnosus
(
JB-1
) reduced GABA
Aα2
mRNA expression in the prefrontal cortex and amygdala, but increased GABA
Aα2
in the hippocampus. Importantly,
L. rhamnosus
(
JB-1
) reduced stress-induced corticosterone and anxiety- and depression-related behavior. Moreover, the neurochemical and behavioral effects were not found in vagotomized mice, identifying the vagus as a major modulatory constitutive communication pathway between the bacteria exposed to the gut and the brain. Together, these findings highlight the important role of bacteria in the bidirectional communication of the gut–brain axis and suggest that certain organisms may prove to be useful therapeutic adjuncts in stress-related disorders such as anxiety and depression.
Calcium store sensor stromal-interaction molecule 1-dependent signaling plays an important role in cervical cancer growth, migration, and angiogenesis
Authors: Chen Yih-Fung , Chiu Wen-Tai , Chen Ying-Ting , Lin Pey-Yun , Huang Huey-Jy , Chou Cheng-Yang , Chang Hsien-Chang , Tang Ming-Jer , Shen Meng-Ru
Published: August 2011

Store-operated Ca
2+
entry (SOCE) is the principal Ca
2+
entry mechanism in nonexcitable cells. Stromal-interaction molecule 1 (STIM1) is an endoplasmic reticulum Ca
2+
sensor that triggers SOCE activation. However, the role of STIM1 in regulating cancer progression remains controversial and its clinical relevance is unclear. Here we show that STIM1-dependent signaling is important for cervical cancer cell proliferation, migration, and angiogenesis. STIM1 overexpression in tumor tissue is noted in 71% cases of early-stage cervical cancer. In tumor tissues, the level of STIM1 expression is significantly associated with the risk of metastasis and survival. EGF-stimulated cancer cell migration requires STIM1 expression and EGF increases the interaction between STIM1 and Orai1 in juxta-membrane areas, and thus induces Ca
2+
influx. STIM1 involves the activation of Ca
2+
-regulated protease calpain, as well as Ca
2+
-regulated cytoplasmic kinase Pyk2, which regulate the focal-adhesion dynamics of migratory cervical cancer cells. Because of an increase of p21 protein levels and a decrease of Cdc25C protein levels, STIM1-silencing in cervical cancer cells significantly inhibits cell proliferation by arresting the cell cycle at the S and G2/M phases. STIM1 also regulates the production of VEGF in cervical cancer cells. Interference with STIM1 expression or blockade of SOCE activity inhibits tumor angiogenesis and growth in animal models, confirming the crucial role of STIM1-mediated Ca
2+
influx in aggravating tumor development in vivo. These results make STIM1-dependent signaling an attractive target for therapeutic intervention.
Targeted enrichment of ancient pathogens yielding the pPCP1 plasmid ofYersinia pestisfrom victims of the Black Death
Authors: Schuenemann Verena J. , Bos Kirsten , DeWitte Sharon , Schmedes Sarah , Jamieson Joslyn , Mittnik Alissa , Forrest Stephen , Coombes Brian K. , Wood James W. , Earn David J. D. , White William , Krause Johannes , Poinar Hendrik N.
Published: August 2011

Although investigations of medieval plague victims have identifiedYersinia pestisas the putative etiologic agent of the pandemic, methodological limitations have prevented large-scale genomic investigations to evaluate changes in the pathogen's virulence over time. We screened over 100 skeletal remains from Black Death victims of the East Smithfield mass burial site (1348–1350, London, England). Recent methods of DNA enrichment coupled with high-throughput DNA sequencing subsequently permitted reconstruction of ten full human mitochondrial genomes (16 kb each) and the full pPCP1 (9.6 kb) virulence-associated plasmid at high coverage. Comparisons of molecular damage profiles between endogenous human andY. pestisDNA confirmed its authenticity as an ancient pathogen, thus representing the longest contiguous genomic sequence for an ancient pathogen to date. Comparison of our reconstructed plasmid against modernY. pestisshows identity with several isolates matching theMedievalisbiovar; however, our chromosomal sequences indicate the victims were infected with aY. pestisvariant that has not been previously reported. Our data reveal that the Black Death in medieval Europe was caused by a variant ofY. pestisthat may no longer exist, and genetic data carried on its pPCP1 plasmid were not responsible for the purported epidemiological differences between ancient and modern forms ofY. pestisinfections.
Primordial neurosecretory apparatus identified in the choanoflagellate
Monosiga brevicollis
Authors: Burkhardt Pawel , Stegmann Christian M. , Cooper Benjamin , Kloepper Tobias H. , Imig Cordelia , Varoqueaux Frédérique , Wahl Markus C. , Fasshauer Dirk
Published: August 2011

SNARE protein-driven secretion of neurotransmitters from synaptic vesicles is at the center of neuronal communication. In the absence of the cytosolic protein Munc18-1, synaptic secretion comes to a halt. Although it is believed that Munc18-1 orchestrates SNARE complexes, its mode of action is still a matter of debate. In particular, it has been challenging to clarify the role of a tight Munc18/syntaxin 1 complex, because this interaction interferes strongly with syntaxin's ability to form a SNARE complex. In this complex, two regions of syntaxin, the
N
-peptide and the remainder in closed conformation, bind to Munc18 simultaneously. Until now, this binary complex has been reported for neuronal tissues only, leading to the hypothesis that it might be a specialization of the neuronal secretion apparatus. Here we aimed, by comparing the core secretion machinery of the unicellular choanoflagellate
Monosiga brevicollis
with that of animals, to reconstruct the ancestral function of the Munc18/syntaxin1 complex. We found that the Munc18/syntaxin 1 complex from
M. brevicollis
is structurally and functionally highly similar to the vertebrate complex, suggesting that it constitutes a fundamental step in the reaction pathway toward SNARE assembly. We thus propose that the primordial secretion machinery of the common ancestor of choanoflagellates and animals has been co-opted for synaptic roles during the rise of animals.
Correlation of in situ mechanosensitive responses of the
Moraxella catarrhalis
adhesin UspA1 with fibronectin and receptor CEACAM1 binding
Authors: Agnew Christopher , Borodina Elena , Zaccai Nathan R. , Conners Rebecca , Burton Nicholas M. , Vicary James A. , Cole David K. , Antognozzi Massimo , Virji Mumtaz , Brady R. Leo
Published: August 2011

Bacterial cell surfaces are commonly decorated with a layer formed from multiple copies of adhesin proteins whose binding interactions initiate colonization and infection processes. In this study, we investigate the physical deformability of the UspA1 adhesin protein from
Moraxella catarrhalis
, a causative agent of middle-ear infections in humans. UspA1 binds a range of extracellular proteins including fibronectin, and the epithelial cellular receptor carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1). Electron microscopy indicates that unliganded UspA1 is densely packed at, and extends about 800 Å from, the
Moraxella
surface. Using a modified atomic force microscope, we show that the adhesive properties and thickness of the UspA1 layer at the cell surface varies on addition of either fibronectin or CEACAM1. This in situ analysis is then correlated with the molecular structure of UspA1. To provide an overall model for UspA1, we have determined crystal structures for two N-terminal fragments which are then combined with a previous structure of the CEACAM1-binding site. We show that the UspA1–fibronectin complex is formed between UspA1 head region and the 13th type-III domain of fibronectin and, using X-ray scattering, that the complex involves an angular association between these two proteins. In combination with a previous study, which showed that the CEACAM1–UspA1 complex is distinctively bent in solution, we correlate these observations on isolated fragments of UspA1 with its in situ response on the cell surface. This study therefore provides a rare direct demonstration of protein conformational change at the cell surface.
Mechanical regulation of vascular growth and tissue regeneration in vivo
Authors: Boerckel Joel D. , Uhrig Brent A. , Willett Nick J. , Huebsch Nathaniel , Guldberg Robert E.
Published: August 2011

New vascular network formation is a critical step in the wound healing process and a primary limiting factor in functional tissue regeneration. Like many tissues, neovascular networks have been shown in vitro to be highly sensitive to mechanical conditions; however, the effects of matrix deformations on neovascular network formation and remodeling in engineered tissue regeneration in vivo have not been evaluated. We quantified the effects of early and delayed functional loading on neovascular growth in a rat model of large bone defect regeneration using compliant fixation plates that were unlocked to allow transfer of ambulatory loads to the defect either at the time of implantation (early), or after 4 wk of stiff fixation (delayed). Neovascular growth and bone regeneration were quantitatively evaluated 3 wk after the onset of loading by contrast-enhanced microcomputed tomography and histology. The initial vascular response to bone injury featured robust angiogenesis and collateral vessel formation, increasing parameters such as vascular volume and connectivity while decreasing degree of anisotropy. Application of early mechanical loading significantly inhibited vascular invasion into the defect by 66% and reduced bone formation by 75% in comparison to stiff plate controls. In contrast, delaying the onset of loading by 4 wk significantly enhanced bone formation by 20% and stimulated vascular remodeling by increasing the number of large vessels and decreasing the number of small vessels. Together, these data demonstrate the mechanosensitivity of neovascular networks and highlight the capacity of biomechanical stimulation to modulate postnatal vascular growth and remodeling.
Mathematical accuracy of Aztec land surveys assessed from records in the
Codex Vergara
Authors: Jorge María del Carmen , Williams Barbara J. , Garza-Hume C. E. , Olvera Arturo
Published: August 2011

Land surveying in ancient states is documented not only for Eurasia but also for the Americas, amply attested by two Acolhua–Aztec pictorial manuscripts from the Valley of Mexico. The
Codex Vergara
and the
Códice de Santa María Asunción
consist of hundreds of drawings of agricultural fields that uniquely record surface areas as well as perimeter measurements. A previous study of the
Codex Vergara
examines how Acolhua–Aztecs determined field area by reconstructing their calculation procedures. Here we evaluate the accuracy of their area values using modern mathematics. The findings verify the overall mathematical validity of the codex records. Three-quarters of the areas are within 5% of the maximum possible value, and 85% are within 10%, which compares well with reported errors by Western surveyors that postdate Aztec–Acolhua work by several centuries.