bluuebunny/crossref_metadata_2025 huggingface dataset:
Principais abordagens teórico-metodológicas sobre a teoria do comportamento: do positivismo ao pós-modernismo
Authors: Ciribeli Joao Paulo , Mendes Wesley de Almeida
Published: January 2016

O artigo buscou identificar as principais correntes teórico-metodológicas que contribuíram para o avanço e o entendimento do comportamento do consumidor, bem como aferir suas nuanças, distinções e semelhanças. Quanto à metodologia, o estudo consiste num ensaio teórico, o que nos remete à revisão bibliográfica, onde pode-se confrontar as ideias dos principais autores que discorrem na área, assim como analisar, de forma didática suas arquições. Sobre os resultados, verificou-se que três modelos contribuição de forma mais substancial ao entendimento do comportamento do consumidor: modernismo, estruturalismo e pós-modernismo. Pode-se constatar também que estes modelos podem ser agrupadas em duas abordagens, a quantitativa e a qualitativa, o que ocasionou, a posteriori, a híbrida. O modernismo, em sua abordagem quantitativa, buscava compreender o comportamento do consumidor de forma objetiva. Apesar de sua orientação quantitativa o estruturalismo, diferentemente do modernismo, buscava conhecer as estruturas dos fatos e objetos observados - tentava extrair a essência da realidade. Com vistas a identificar a estrutura, os padrões e os vícios de comportamento esta abordagem contribui na medida em que não se atenta ao que, como e quando se consome, mas às relações entre os objetos - considerava por tanto o ambiente no qual o consumidor está inserido. Embora o estruturalismo buscasse a simplificação dos fatos por meio da eliminação do que é superficial, pouca aplicabilidade teve este modelo, devido a dificuldade em se chegar à essência dos fatos. Já o pós-modernismo apresenta uma abordagem qualitativa, onde as experiências, as crenças, os valores e a carga simbólica do comportamento do indivíduo passam a preponderar sobre a análise das massas.
O clima organizacional e a saúde dos colaboradores em educação em uma escola estadual pernambucana
Authors: Vieira Maria das Graças , Almeida Fernanda Matos de Moura , Santos Camila Tayná , Lira Jordana Soares de
Published: January 2016

Este artigo apresenta um estudo realizado sobre o clima organizacional na escola Estadual Maria Auxiliadora Liberato. O objetivo constitui-se em analisar o clima atual da organização, o grau de satisfação dos colaboradores e as relações destes fatores com a saúde dos mesmos. A metodologia utilizada para realização da pesquisa foi um estudo de caso aplicado à instituição, tendo como instrumento de coleta de dados um questionário, distribuídos ao corpo docente e a todos os funcionários de todos os níveis hierárquicos daquela instituição, utilizando a população total para análise de dados. Percebe-se que a organização possui uma liderança bastante participativa e que a mesma é reconhecida por todos os membros da instituição. Ficou também constatado que os colaboradores em sua maioria se identificam com a organização e sentem prazer por trabalhar nela. Entretanto, verificou-se também, que problemas relacionados à saúde estavam ligados a algumas variáveis que apresentaram menores níveis de satisfação (insatisfação) de acordo com os respondentes.
Sevend Pounds y Biología. Zoología y transplante de órganos en el epílogo del film, una experiencia en formación de docente
Authors: Grilli Silva Javier
Published: January 2016

Las experiencias didácticas vividas en formación docente inicial tienen un fuerte impacto en la conformación del perfil profesional del profesor. Estas deben ser coincidente con los fines que se tienen para la enseñanza de las ciencias en el nivel educativo medio: formar ciudadanos críticos. Propuestas de enseñanza de la zoología con un enfoque CTS ofrecen una visión integrada, interdisciplinar, y problematizadora del saber científico, que conectan la ciencia con la realidad que vive el individuo en la sociedad. La utilización del cine como recurso didáctico permite vincular de manera muy favorable los avances científicos y tecnológicos con aspectos sociales. La experiencia didáctica que presentamos desarrolló una mirada crítica al film Seven Pounds con soporte en la Zoología, Medicina y el Derecho. Por medio de una guía se realizó el visionado del film, lográndose movilizar conocimientos científicos, reflexionar con base en ellos y aplicarlos o usarlos en situaciones específicas.
Changes in the characteristics of nonvolatile memory depending on Au nanoparticle size for p- and n-type channels
Authors: Hattori Shigeki , Terai Masaya , Nishizawa Hideyuki
Published: January 2016

Nonvolatile memory capacitors were fabricated using immobilized Au nanoparticles (NPs) on p- and n-type doped Si substrates with Au NPs of diameter 3 and 2 nm immobilized by self-assembled monolayers on the Si surface, and the charge density and data retention of the programmed nonvolatile memories were found to change dramatically depending on both nanoparticle size and channel type (p-/n-). In the case of capacitors fabricated on p-Si substrates, large charge density was observed in devices using 3 nm Au NPs under low electric fields, and devices using 2 nm Au NPs were found to exhibit larger charge densities compared with devices using 3 nm Au NPs under high electric fields. Additionally, data retention was better for p-Si devices using 2 nm Au NPs compared with 3 nm Au NPs. However, data retention was worse for n-Si devices than for p-Si devices.
Dependence of Purcell effect on fluorescence wavelength in dye molecules on metal–dielectric multilayer hyperbolic metamaterials
Authors: Tsurumachi Noriaki , Izawa Hayato , Tomioka Ryo , Sakata Tomohiro , Suzuki Makoto , Tanaka Yasuhiro , Shimokawa Fusao , Nakanishi Shunsuke
Published: January 2016

Recently, the enhancement of spontaneous emission, i.e., broadband Purcell effect, has been achieved using hyperbolic metamaterials. Hyperbolic metamaterials, which can be realized using a metal–dielectric multilayer structure, have an extremely large optical anisotropy of permittivity in both the parallel and perpendicular directions to the propagation of light, especially when the signs of permittivities in both directions differ. In this study, we investigated the conditions for realizing the broadband Purcell effect using dye molecules with different fluorescence wavelengths. Our fabricated metal–dielectric multilayer structure exhibited hyperbolic dispersion at wavelengths beyond 500 nm. In the case of coumarin 500 whose fluorescence peak is located at 500 nm, no broadband Purcell effect was observed. However, in the case of pyridine 1 whose fluorescence peak is located at 650 nm, we observed the successfull fluorescence lifetime shortening, i.e., the broadband Purcell effect.
Quasi-single crystal SiGe on insulator by Au-induced crystallization for flexible electronics
Authors: Sadoh Taizoh , Park Jong-Hyeok , Aoki Rikuta , Miyao Masanobu
Published: January 2016

Orientation-controlled large-grain (≥10 µm) crystal, i.e., quasi-single crystal, Ge-rich (≥50%) SiGe on insulator grown at low temperatures (≤300 °C) are desired for realization of high-performance flexible electronics. To achieve this, the Au-induced crystallization technique using a-SiGe/Au stacked structures has been developed. This enables formation of (111)-oriented large-grain (≥10 µm) Si1−

x
Ge
x
(x ≥ 0.5) crystals on insulating substrates at low temperatures (300 °C). The surface layers of the grown SiGe crystals have uniform lateral composition profiles. By using this technique, formation of quasi-single crystal Ge on flexible plastic sheets is demonstrated. This technique will be useful to realize high-performance flexible electronics.
Transient‐state kinetic analysis of complex formation between photoprotein clytin and GFP from jellyfish Clytia gregaria
Authors: Eremeeva Elena V. , van Berkel Willem J.H. , Vysotski Eugene S.
Published: January 2016

Luminous organisms use different protein‐mediated strategies to modulate light emission color. Here, we report the transient‐state kinetic studies of the interaction between photoprotein clytin from Clytia gregaria and its antenna protein, cgreGFP. We propose that cgreGFP forms a transient complex with Ca2+‐bound clytin before the excited singlet state of the coelenteramide product is formed. From the spectral distribution and donor‐acceptor separation distance, we infer that clytin reaction intermediates may interact only with the middle side part of cgreGFP.
The Bisphenol A analogue Bisphenol S binds to K‐Ras4B – implications for ‘BPA‐free’ plastics
Authors: Schöpel Miriam , Herrmann Christian , Scherkenbeck Jürgen , Stoll Raphael
Published: January 2016

K‐Ras4B is a small GTPase that belongs to the Ras superfamily of guanine nucleotide‐binding proteins. GTPases function as molecular switches in cells and are key players in intracellular signalling. Ras has been identified as an oncogene and is mutated in more than 20% of human cancers. Here, we report that Bisphenol S binds into a binding pocket of K‐Ras4B previously identified for various low molecular weight compounds. Our results advocate for more comprehensive safety studies on the toxicity of Bisphenol S, as it is frequently used for Bisphenol A‐free food containers.
Sahel decadal rainfall variability and the role of model horizontal resolution
Authors: Vellinga Michael , Roberts Malcolm , Vidale Pier Luigi , Mizielinski Matthew S. , Demory Marie‐Estelle , Schiemann Reinhard , Strachan Jane , Bain Caroline
Published: January 2016

Substantial low‐frequency rainfall fluctuations occurred in the Sahel throughout the twentieth century, causing devastating drought. Modeling these low‐frequency rainfall fluctuations has remained problematic for climate models for many years. Here we show using a combination of state‐of‐the‐art rainfall observations and high‐resolution global climate models that changes in organized heavy rainfall events carry most of the rainfall variability in the Sahel at multiannual to decadal time scales. Ability to produce intense, organized convection allows climate models to correctly simulate the magnitude of late‐twentieth century rainfall change, underlining the importance of model resolution. Increasing model resolution allows a better coupling between large‐scale circulation changes and regional rainfall processes over the Sahel. These results provide a strong basis for developing more reliable and skilful long‐term predictions of rainfall (seasons to years) which could benefit many sectors in the region by allowing early adaptation to impending extremes.
Coming of age in Roman Britain: Osteological evidence for pubertal timing
Authors: Arthur Nichola A. , Gowland Rebecca L. , Redfern Rebecca C.
Published: January 2016

Objectives

Puberty is a key transitional phase of the human life course, with important biological and social connotations. Novel methods for the identification of the pubertal growth spurt and menarche in skeletal remains have recently been proposed (Shapland and Lewis, 2013, 2014). In this study we applied the methods to two Romano‐British cemetery samples (1st‐early 5th centuries AD) in order to investigate the timing of puberty during this period and further assess the veracity of the methods.

Materials and Methods

Shapland and Lewis' methods (2013, 2014) were applied to 38 adolescents (aged 8–20 years) from the British cemetery sites of Roman London (1st‐early 5th centuries AD) and Queenford Farm, Oxfordshire (4th‐early 5th centuries AD).

Results

Overall, the Romano‐British males and females experienced the onset of puberty at similar ages to modern European adolescents, but subsequently experienced a longer period of pubertal development. Menarche occurred between the ages of 15 and 17 years for these Romano‐British females, around 2 to 4 years later than for present‐day European females.

Discussion

The observed Romano‐British pattern of pubertal timing has various possible explanations, including exposure to environmental stressors in early urban environments. The pattern of pubertal timing is largely congruent with social age transitions alluded to in ancient texts and funerary evidence for this period. While there are limitations to the application of these techniques to archaeological samples, they were successfully applied in this study, and may have important implications for understandings of past life courses, as well as providing a long‐term perspective on pubertal timing and biocultural interactions. Am J Phys Anthropol 159:698–713, 2016. © 2016 Wiley Periodicals, Inc.
Fischer‐Tropsch synthesis: Effect of solvent on the H2‐D2 isotopic exchange rate over an activated cobalt catalyst
Authors: Pendyala Venkat Ramana Rao , Shafer Wilson D. , Jacobs Gary , Davis Burtron H.
Published: January 2016

The effect of solvent on the hydrogen‐deuterium isotopic homomolecular exchange over a traditional Fischer‐Tropsch cobalt catalyst (25 % Co/Al2O3) was investigated using a plug flow reactor at two different reaction temperatures (room temperature (26 °C) and –20 °C) and at atmospheric pressure. In this study, three different solvents were tested, including n‐pentane, n‐hexadecane, and C‐30 oil. The consumption of H2 and D2 is the same, and the concentration of the HD produced is twice the consumption of H2 or D2 at dry (without solvent) conditions. At room temperature and at –20 °C, conditions without solvent exhibited 100 mol% exchange with the formation of H2:HD:D2 having a 1:2:1 ratio. For n‐pentane solvent, the exchange rates were ∼97 and ∼80 mol% at 26 and −20 °C, respectively. For the n‐hexadecane and C30 oil solvents, the initial exchange rate was ∼50 mol%, with the exchange rate decreasing over time. The lower exchange rate with the n‐hexadecane and C30 oil solvents, and also n‐pentane at –20 °C, is likely due primarily to the limited mobility of reactant molecules in the liquid‐filled pores of the catalyst. Blocking or covering of the pores of the catalyst depends on the molecular mass and density of the solvent. No isotopic partitioning preference was observed at two different temperatures and various solvents for the active cobalt catalyst.
Climate and land cover effects on the temperature of Puget Sound streams
Authors: Cao Qian , Sun Ning , Yearsley John , Nijssen Bart , Lettenmaier Dennis P.
Published: January 2016

We apply an integrated hydrology‐stream temperature modeling system, DHSVM‐RBM, to examine the response of the temperature of the major streams draining to Puget Sound to land cover and climate change. We first show that the model construct is able to reconstruct observed historic streamflow and stream temperature variations at a range of time scales. We then explore the relative effect of projected future climate and land cover change, including riparian vegetation, on streamflow and stream temperature. Streamflow in summer is likely to decrease as the climate warms especially in snowmelt‐dominated and transient river basins despite increased streamflow in their lower reaches associated with urbanization. Changes in streamflow also result from changes in land cover, and changes in stream shading result from changes in riparian vegetation, both of which influence stream temperature. However, we find that the effect of riparian vegetation changes on stream temperature is much greater than land cover change over the entire basin especially during summer low flow periods. Furthermore, while future projected precipitation change will have relatively modest effects on stream temperature, projected future air temperature increases will result in substantial increases in stream temperature especially in summer. These summer stream temperature increases will be associated both with increasing air temperature, and projected decreases in low flows. We find that restoration of riparian vegetation could mitigate much of the projected summer stream temperature increases. We also explore the contribution of riverine thermal loadings to the heat balance of Puget Sound, and find that the riverine contribution is greatest in winter, when streams account for up to 1/8 of total thermal inputs (averaged from December through February), with larger effects in some sub‐basins. We project that the riverine impact on thermal inputs to Puget Sound will become greater with both urbanization and climate change in winter but become smaller in summer due to climate change. Copyright © 2016 John Wiley & Sons, Ltd.
Differences in the vascular tree of the femoral trochlear growth cartilage at osteochondrosis‐susceptible sites in foals revealed by SWI 3T MRI
Authors: Martel Gabrielle , Kiss Sabrina , Gilbert Guillaume , Anne‐Archard Nicolas , Richard Hélène , Moser Thomas , Laverty Sheila
Published: January 2016

Focal ischemic chondronecrosis of epiphyseal growth cartilage (EGC) during endochondral ossification is believed to be a key early event on the pathway to osteochondrosis (OC) in both animals and humans. The lateral ridge of the equine trochlea is a site where severe osteochondritis dissecans lesions frequently arise and is a model for the study of naturally occurring disease. Non‐invasive imaging to investigate EGC vascularity may help elucidate why focal ischemia occurs. 3T MRI susceptibility‐weighted imaging (SWI) of femoral trochlea of OC predisposed (n = 10) and control (n = 6) day‐old foals, with minimal joint loading after birth, was performed. SWI and 3D images revealed the EGC vascular architecture without a contrast agent, and matched histologic observations. No vascular lesions were identified. There was no difference in the vascular density and architecture between control and OC specimens, but a striking difference in vascular pattern was seen at the OC‐predilected site in the lateral ridge of the trochlea in all specimens, when compared to the medial ridge of the trochlea, where OC lesions are rarely observed. This site was less ossified with more perichondrial vessels not yet bridging with the subchondral bone. Furthermore, the mean vascular density of all specimens was significantly higher at this site. We speculate that joint morphology and focal internal trauma on this site with a unique vascular architecture may trigger ischemic events at this site. SWI permitted visualization of EGC in young foals with a clinical 3T MRI and paves the way for non‐destructive longitudinal studies to improve understanding of OC in all species. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1539–1546, 2016.
Patient‐Reported Defecation and Micturition Problems Among Adults Treated for Sacrococcygeal Teratoma During Childhood—The Need for New Surveillance Strategies
Authors: Kremer Marijke E.B. , Derikx Joep P.M. , van Baren Robertine , Heij Hugo A. , Wijnen Marc H.W.A. , Wijnen René M.H. , van der Zee David C. , van Heurn Ernest L.W.E.
Published: January 2016

Background

To evaluate defecation and micturition complaints in adults treated for sacrococcygeal teratoma (SCT) during childhood and to identify risk factors for soiling, urinary incontinence, and constipation beyond childhood.

Procedure

Records of patients aged ≥18 treated for SCT during infancy in the Netherlands were retrospectively reviewed. Frequency and severity of soiling, constipation, and urinary incontinence were evaluated using questionnaires designed in line with the Krickenbeck classification. Problems during childhood were compared to outcomes at adult age in part of the cohort. Associations between patient‐ and disease‐related factors with complaints beyond childhood were analyzed with the chi‐square test or Fisher's exact test, when appropriate.

Results

Of 47 included patients (mean age 26.2 years, SD ±6.5), 49% reported at least one defecation or micturition complaint. Urinary incontinence was present in 30% and had a greater negative impact than soiling (24%). Ten patients (21%) reported constipation; five found this severely bothering. Three patients reported social restrictions due to defecation or micturition complaints (6.4%). While sex and tumor histology were not identified as risk factors, a tumor diameter of >10 cm and Altman type I or type II SCT were associated with constipation during adulthood.

Conclusions

One‐third of the patients treated for SCT during childhood reported urinary and defecation problems beyond childhood. In only a minority of cases, these led to social restrictions. A greater tumor diameter was associated with a higher risk of constipation during adulthood. Prolonged surveillance strategies are advised for all patients with SCT.
Modeling of visco‐hyperelastic behavior of transversely isotropic functionally graded rubbers
Authors: Anani Yavar , Rahimi Gholamhosein
Published: January 2016

In this article, visco‐hyperelastic constitutive model is developed to describe the rate‐dependent behavior of transversely isotropic functionally graded rubber‐like materials at finite deformations. Zener model that consists of Maxwell element parallel to a hyperelastic equilibrium spring is used in this article. Steady state response is described by equilibrium hyperelastic spring and rate‐dependence behavior is modeled by Maxwell element that consists of a hyperelastic intermediate spring and a nonlinear viscous damper. Modified and reinforced neo‐Hookean strain energy function is proposed for the two hyperelastic springs. The mechanical properties and material constants of strain energy function are graded along the axial direction based on exponential function. A history‐integral method has been used to develop a constitutive equation for modeling the behavior of the model. The applied history integral method is based on the Kaye‐BKZ theory. The material constant parameters appeared in the formulation have been determined with the aid of available uniaxial tensile experimental tests for a specific material and the results are compared to experimental results. It is then concluded that, the proposed constitutive equation is quite proficient in forecasting the behavior of rubber‐like materials in different deformation and wide ranges of strain rate. POLYM. ENG. SCI., 56:342–347, 2016. © 2016 Society of Plastics Engineers
Time and Intensity Weighted Indices of Fluvial Processes: a Case Study from the Kootenai River, USA
Authors: Egger G. , Politti E. , Lautsch E. , Benjankar R. M. , Rood S. B.
Published: January 2016

Within riparian landscapes, river flows and stages determine habitat gradients from less to more dynamic, and these support different plant species and their life history stages that are adapted to specific positions along these gradients. The gradients are characterized by physical processes that vary in magnitude and duration, and these shape the riparian vegetation communities. Consequently, natural riparian ecosystems are very dynamic, and the river disturbance regime is essential for sustaining ecosystem health. However, although the importance of disturbance is well accepted, disturbance regimes are poorly understood. This study was undertaken to develop indices capable of characterizing riparian habitats by considering flood magnitude and the elapsed time after flood disturbance, that is, the history that influenced the present vegetation composition. The indices were tested along two reaches of the Kootenai River in Idaho, USA, with braided versus meandering channel forms. The case study spanned a 31‐year period and emphasized two major disturbance components, the morphodynamic influence of velocity and shear stress and the flood or inundation duration. Computed indices were tested for consistency and then used to characterize different riparian vegetation development and succession phases. The statistical analysis revealed high correspondence among the calculated indices and differences across the different successional stages and between the two reaches. This demonstrated the utility of the time and intensity weighted indices to analyse the fluvial patterns that support different riparian vegetation communities, and this could be applicable for riparian management, mitigation, conservation and restoration. Copyright © 2016 John Wiley & Sons, Ltd.
Evaluating the impact of PSC inspectors’ professional profile: a case study of the Spanish Maritime Administration
Authors: Ravira Francisco J. , Piniella Francisco
Published: January 2016

Full-scale globalisation of trade has been accompanied by a progressive liberalisation of maritime transport. The proliferation of open registries has created a situation in which Port State Control (PSC) has become much more effective than the feeble or non-existent control exercised by those States. This study has been conducted on the influence of the professional profile of inspectors on inspection results. The objective of our paper was to evaluate the impact of PSC inspectors’ professional profile by conducting a case study of the Spanish Maritime Administration. The paper concludes with a discussion of the correlation between deficiencies detected and professional profiles.
Evidence-based transition planning practices for secondary students with disabilities: What has Australia signed up for?
Authors: O’Neill Sue C. , Strnadová Iva , Cumming Therese M.
Published: January 2016

There are no Commonwealth or state laws in Australia that require educational authorities to provide individualised transition plans (ITPs) to secondary students with disabilities. It is argued that, in lieu of legislation, Australia's signed commitment to international treaties and national policies obliges educational jurisdictions to provide ITPs to secondary students with disabilities to improve the postschool outcomes for this vulnerable population. Document analysis methods were used to analyse these international treaties and national policies for statements aligned with evidence-based transition skills and predictors. Almost 90 transition-aligned statements were found, accounting for all evidence-based transition skill categories and most of the transition predictor categories. Implications for policymakers and educational jurisdictions are discussed.
The effects of using axial magnetic field in extreme ultraviolet photon sources for nanolithography – recent integrated simulation
Authors: Sizyuk V. , Hassanein A.
Published: January 2016

We developed a comprehensive model for simulating laser/target interaction in the presence of external axial magnetic fields. The model was integrated into the framework of the HEIGHTS-LPP computer simulation package and benchmarked with recent experimental results. The package was then used to study the angular distribution of extreme ultraviolet (EUV) photon output in plasmas produced in tin planar targets by a Nd:YAG laser. A moderate (0.5 T) permanent magnetic field does not affect EUV source evolution and output. More effective control of plasma plume expansion should be based on magnetic field gradients, that is, on the temporary varying magnetic fields as a magnetic pinch. Analysis of angular EUV output showed strong anisotropy of photon emissions. We found that the correct monitoring angle (i.e., at which the measured EUV flux corresponds to the averaged value after the correctly integrated angular distribution) does not depend on laser irradiance in the studied range and is equivalent to ~60°. We recommend arranging the EUV sensors accordingly in experiments with planar tin targets.
Characterization of ellipsoids as K-dense sets
Authors: Magnanini Rolando , Marini Michele
Published: January 2016

Let K ⊂ ℝN be any convex body containing the origin. A measurable set G ⊂ ℝN with finite and positive Lebesgue measure is said to be K-dense if, for any fixed r > 0, the measure of G ⋂ (x + rK) is constant when x varies on the boundary of G (here, x + rK denotes a translation of a dilation of K). In a previous work, we proved for the case N = 2 that if G is K-dense, then both G and K must be homothetic to the same ellipse. Here, we completely characterize K-dense sets in ℝN: if G is K-dense, then both G and K must be homothetic to the same ellipsoid. Our proof, which builds upon results obtained in our previous work, relies on an asymptotic formula for the measure of G ⋂ (x + rK) for large values of the parameter r and a classical characterization of ellipsoids due to Petty.
PI3Kδ promotes CD4+ T‐cell interactions with antigen‐presenting cells by increasing LFA‐1 binding to ICAM‐1
Authors: Garçon Fabien , Okkenhaug Klaus
Published: January 2016

Activation of T lymphocytes by peptide/major histocompatibility complex on antigen‐presenting cells (APCs) involves dynamic contacts between the two cells, during which T cells undergo marked morphological changes. These interactions are facilitated by integrins. Activation of the T cells increases the binding of the integrin lymphocyte function‐associated antigen 1 (LFA‐1) expressed by T cells to intercellular adhesion molecule (ICAM)‐1 and ICAM‐2 expressed by APCs. The signalling pathways that control integrin affinities are incompletely defined. The phosphoinositide 3‐kinases (PI3Ks) generate second‐messenger signalling molecules that control cell growth, proliferation, differentiation and trafficking. Here we show that in T cells, PI3Kδ attenuates the activation of Rac1, but sustains the activation of Rap1. Consequently, PI3Kδ increases LFA‐1‐dependent adhesion to form stable conjugates with APCs. Increased Rap1 activity and LFA‐1 adhesion were only in part mediated by the downstream kinase Akt, suggesting the involvement of additional phosphatidylinositol(3,4,5)P3‐binding proteins. These results establish a link between PI3K activity, cytoskeletal changes and integrin binding and help explain the impaired T‐cell‐dependent immune responses in PI3Kδ‐deficient mice.
BAP1/ASXL1 recruitment and activation for H2A deubiquitination
Authors: Sahtoe Danny D. , van Dijk Willem J. , Ekkebus Reggy , Ovaa Huib , Sixma Titia K.
Published: January 2016

The deubiquitinating enzyme BAP1 is an important tumor suppressor that has drawn attention in the clinic since its loss leads to a variety of cancers. BAP1 is activated by ASXL1 to deubiquitinate mono-ubiquitinated H2A at K119 in Polycomb gene repression, but the mechanism of this reaction remains poorly defined. Here we show that the BAP1 C-terminal extension is important for H2A deubiquitination by auto-recruiting BAP1 to nucleosomes in a process that does not require the nucleosome acidic patch. This initial encounter-like complex is unproductive and needs to be activated by the DEUBAD domains of ASXL1, ASXL2 or ASXL3 to increase BAP1’s affinity for ubiquitin on H2A, to drive the deubiquitination reaction. The reaction is specific for Polycomb modifications of H2A as the complex cannot deubiquitinate the DNA damage-dependent ubiquitination at H2A K13/15. Our results contribute to the molecular understanding of this important tumor suppressor.
Exosomes as nanocarriers for systemic delivery of the Helicobacter pylori virulence factor CagA
Authors: Shimoda Asako , Ueda Koji , Nishiumi Shin , Murata-Kamiya Naoko , Mukai Sada-atsu , Sawada Shin-ichi , Azuma Takeshi , Hatakeyama Masanori , Akiyoshi Kazunari
Published: January 2016

CagA, encoded by cytotoxin-associated gene A (cagA), is a major virulence factor of Helicobacter pylori, a gastric pathogen involved in the development of upper gastrointestinal diseases. Infection with cagA-positive H. pylori may also be associated with diseases outside the stomach, although the mechanisms through which H. pylori infection promotes extragastric diseases remain unknown. Here, we report that CagA is present in serum-derived extracellular vesicles, known as exosomes, in patients infected with cagA-positive H. pylori (n = 4). We also found that gastric epithelial cells inducibly expressing CagA secrete exosomes containing CagA. Addition of purified CagA-containing exosomes to gastric epithelial cells induced an elongated cell shape, indicating that the exosomes deliver functional CagA into cells. These findings indicated that exosomes secreted from CagA-expressing gastric epithelial cells may enter into circulation, delivering CagA to distant organs and tissues. Thus, CagA-containing exosomes may be involved in the development of extragastric disorders associated with cagA-positive H. pylori infection.
Functional inhibition of urea transporter UT-B enhances endothelial-dependent vasodilatation and lowers blood pressure via L-arginine-endothelial nitric oxide synthase-nitric oxide pathway
Authors: Sun Yi , Lau Chi-Wai , Jia Yingli , Li Yingjie , Wang Weiling , Ran Jianhua , Li Fei , Huang Yu , Zhou Hong , Yang Baoxue
Published: January 2016

Mammalian urea transporters (UTs), UT-A and UT-B, are best known for their role in urine concentration. UT-B is especially distributed in multiple extrarenal tissues with abundant expression in vascular endothelium, but little is known about its role in vascular function. The present study investigated the physiological significance of UT-B in regulating vasorelaxations and blood pressure. UT-B deletion in mice or treatment with UT-B inhibitor PU-14 in Wistar-Kyoto rats (WKYs) and spontaneous hypertensive rats (SHRs) reduced blood pressure. Acetylcholine-induced vasorelaxation was significantly augmented in aortas from UT-B null mice. PU-14 concentration-dependently produced endothelium-dependent relaxations in thoracic aortas and mesenteric arteries from both mice and rats and the relaxations were abolished by Nω-nitro-L-arginine methyl ester. Both expression and phosphorylation of endothelial nitric oxide synthase (eNOS) were up-regulated and expression of arginase I was down-regulated when UT-B was inhibited both in vivo and in vitro. PU-14 induced endothelium-dependent relaxations to a similar degree in aortas from 12 weeks old SHRs or WKYs. In summary, here we report for the first time that inhibition of UT-B plays an important role in regulating vasorelaxations and blood pressure via up-regulation of L-arginine-eNOS-NO pathway and it may become another potential therapeutic target for the treatment of hypertension.
Coral mucus fuels the sponge loop in warm- and cold-water coral reef ecosystems
Authors: Rix Laura , de Goeij Jasper M. , Mueller Christina E. , Struck Ulrich , Middelburg Jack J. , van Duyl Fleur C. , Al-Horani Fuad A. , Wild Christian , Naumann Malik S. , van Oevelen Dick
Published: January 2016

Shallow warm-water and deep-sea cold-water corals engineer the coral reef framework and fertilize reef communities by releasing coral mucus, a source of reef dissolved organic matter (DOM). By transforming DOM into particulate detritus, sponges play a key role in transferring the energy and nutrients in DOM to higher trophic levels on Caribbean reefs via the so-called sponge loop. Coral mucus may be a major DOM source for the sponge loop, but mucus uptake by sponges has not been demonstrated. Here we used laboratory stable isotope tracer experiments to show the transfer of coral mucus into the bulk tissue and phospholipid fatty acids of the warm-water sponge Mycale fistulifera and cold-water sponge Hymedesmia coriacea, demonstrating a direct trophic link between corals and reef sponges. Furthermore, 21–40% of the mucus carbon and 32–39% of the nitrogen assimilated by the sponges was subsequently released as detritus, confirming a sponge loop on Red Sea warm-water and north Atlantic cold-water coral reefs. The presence of a sponge loop in two vastly different reef environments suggests it is a ubiquitous feature of reef ecosystems contributing to the high biogeochemical cycling that may enable coral reefs to thrive in nutrient-limited (warm-water) and energy-limited (cold-water) environments.
Comparative transcriptome analysis reveals insights into the streamlined genomes of haplosclerid demosponges
Authors: Guzman Christine , Conaco Cecilia
Published: January 2016

Sponges (Porifera) are one of the most ancestral metazoan groups. They are characterized by a simple body plan lacking the true tissues and organ systems found in other animals. Members of this phylum display a remarkable diversity of form and function and yet little is known about the composition and complexity of their genomes. In this study, we sequenced the transcriptomes of two marine haplosclerid sponges belonging to Demospongiae, the largest and most diverse class within phylum Porifera and compared their gene content with members of other sponge classes. We recovered 44,693 and 50,067 transcripts expressed in adult tissues of Haliclona amboinensis and Haliclona tubifera, respectively. These transcripts translate into 20,280 peptides in H. amboinensis and 18,000 peptides in H. tubifera. Genes associated with important signaling and metabolic pathways, regulatory networks, as well as genes that may be important in the organismal stress response, were identified in the transcriptomes. Futhermore, lineage-specific innovations were identified that may be correlated with observed sponge characters and ecological adaptations. The core gene complement expressed within the tissues of adult haplosclerid demosponges may represent a streamlined and flexible genetic toolkit that underlies the ecological success and resilience of sponges to environmental stress.
The nature of Ordovician limestone-marl alternations in the Oslo-Asker District (Norway): witnesses of primary glacio-eustasy or diagenetic rhythms?
Authors: Amberg Chloé E. A. , Collart Tim , Salenbien Wout , Egger Lisa M. , Munnecke Axel , Nielsen Arne T. , Monnet Claude , Hammer Øyvind , Vandenbroucke Thijs R. A.
Published: January 2016

Ordovician limestone-marl alternations in the Oslo-Asker District have been interpreted as signaling glacio-eustatic lowstands, which would support a prolonged “Early Palaeozoic Icehouse”. However, these rhythmites could alternatively reflect differential diagenesis, without sedimentary trigger. Here, we test both hypotheses through one Darriwilian and three Katian sections. Our methodology consists of a bed-by-bed analysis of palynological (chitinozoan) and geochemical (XRF) data, to evaluate whether the limestone/marl couplets reflect an original cyclic signal. The results reveal similar palynomorph assemblages in limestones and marls. Exceptions, which could be interpreted as reflecting palaeoclimatological fluctuations, exist at the species level:Ancyrochitina bornholmensisseems to be more abundant in the marl samples from the lower Frognerkilen Formation on Nakkholmen Island. However, these rare cases where chitinozoans differ between limestone/marl facies are deemed insufficient for the identification of original cyclicity. The geochemical data show a near-perfect correlation between insoluble elements in the limestone and the marls, which indicates a similar composition of the potential precursor sediment, also in the Frognerkilen Formation. This is consistent with the palynological data. Although an original cyclic pattern could still be recorded by other, uninvestigated parameters, our palaeontological and geochemical data combined do not support the presence of such a signal.
High Electron Mobility in Epitaxial Trilayer Graphene on Off-axis SiC(0001)
Authors: Hajlaoui Mahdi , Sediri Haikel , Pierucci Debora , Henck Hugo , Phuphachong Thanyanan , Silly Mathieu G. , de Vaulchier Louis-Anne , Sirotti Fausto , Guldner Yves , Belkhou Rachid , Ouerghi Abdelkarim
Published: January 2016

The van de Waals heterostructure formed by an epitaxial trilayer graphene is of particular interest due to its unique tunable electronic band structure and stacking sequence. However, to date, there has been a lack in the fundamental understanding of the electronic properties of epitaxial trilayer graphene. Here, we investigate the electronic properties of large-area epitaxial trilayer graphene on a 4° off-axis SiC(0001) substrate. Micro-Raman mappings and atomic force microscopy (AFM) confirmed predominantly trilayer on the sample obtained under optimized conditions. We used angle-resolved photoemission spectroscopy (ARPES) and Density Functional Theory (DFT) calculations to study in detail the structure of valence electronic states, in particular the dispersion of π bands in reciprocal space and the exact determination of the number of graphene layers. Using far-infrared magneto-transmission (FIR-MT), we demonstrate, that the electron cyclotron resonance (CR) occurs between Landau levels with a (B)1/2 dependence. The CR line-width is consistent with a high Dirac fermions mobility of ~3000 cm2·V−1·s−1 at 4 K.
MicroRNAs in Honey Bee Caste Determination
Authors: Ashby Regan , Forêt Sylvain , Searle Iain , Maleszka Ryszard
Published: January 2016

The cellular mechanisms employed by some organisms to produce contrasting morphological and reproductive phenotypes from the same genome remains one of the key unresolved issues in biology. Honeybees (Apis mellifera) use differential feeding and a haplodiploid sex determination system to generate three distinct organismal outcomes from the same genome. Here we investigate the honeybee female and male caste-specific microRNA and transcriptomic molecular signatures during a critical time of larval development. Both previously undetected and novel miRNAs have been discovered, expanding the inventory of these genomic regulators in invertebrates. We show significant differences in the microRNA and transcriptional profiles of diploid females relative to haploid drone males as well as between reproductively distinct females (queens and workers). Queens and drones show gene enrichment in physio-metabolic pathways, whereas workers show enrichment in processes associated with neuronal development, cell signalling and caste biased structural differences. Interestingly, predicted miRNA targets are primarily associated with non-physio-metabolic genes, especially neuronal targets, suggesting a mechanistic disjunction from DNA methylation that regulates physio-metabolic processes. Accordingly, miRNA targets are under-represented in methylated genes. Our data show how a common set of genetic elements are differentially harnessed by an organism, which may provide the remarkable level of developmental flexibility required.
HIV-1 gp120 induces type-1 programmed cell death through ER stress employing IRE1α, JNK and AP-1 pathway
Authors: Shah Ankit , Vaidya Naveen K. , Bhat Hari K. , Kumar Anil
Published: January 2016

The ER stress-mediated apoptosis has been implicated in several neurodegenerative diseases; however, its role in HIV/neuroAIDS remains largely unexplored. The present study was undertaken to assess the involvement and detailed mechanism of IRE1α pathway in HIV-1 gp120-mediated ER stress and its possible involvement in cell death. Various signaling molecules for IRE1α pathway were assessed using SVGA cells, primary astrocytes and gp120 transgenic mice, which demonstrated gp120-mediated increase in phosphorylated JNK, XBP-1 and AP-1 leading to upregulation of CHOP. Furthermore, HIV-1 gp120-mediated activation of IRE1α also increased XBP-1 splicing. The functional consequence of gp120-mediated ER stress was determined via assessment of gp120-mediated cell death using PI staining and MTT assay. The gp120-mediated cell death also involved caspase-9/caspase-3-mediated apoptosis. These findings were confirmed with the help of specific siRNA for IRE1α, JNK, AP-1, BiP and CHOP showing significant reduction in gp120-mediated CHOP expression. Additionally, silencing all the intermediates also reduced the gp120-mediated cell death and caspase-9/caspase-3 activation at differential levels. This study provides ER-stress as a novel therapeutic target in the management of gp120-mediated cell death and possibly in the treatment of neuroAIDS.
Chi and dLMO function antagonistically on Notch signaling through directly regulation of fng transcription
Authors: Han Hui , Fan Jialin , Xiong Yue , Wu Wenqing , Lu Yi , Zhang Lei , Zhao Yun
Published: January 2016

Gene apterous (ap), chip (chi) and beadex (bx) play important roles in the dorsal-ventral compartmentalization in Drosophila wing discs. Meanwhile, Notch signaling is essential to the same process. It has been reported that Ap and Chi function as a tetramer to regulate Notch signaling. At the same time, dLMO (the protein product of gene bx) regulates the activity of Ap by competing its binding with Chi. However, the detailed functions of Chi and dLMO on Notch signaling and the relevant mechanisms remain largely unknown. Here, we report the detailed functions of Chi and dLMO on Notch signaling. Different Chi protein levels in adjacent cells could activate Notch signaling mainly in the cells with higher level of Chi. dLMO could induce antagonistical phenotypes on Notch signaling compared to that induced by Chi. These processes depend on their direct regulation of fringe (fng) transcription.
Molecular hydrogen regulates gene expression by modifying the free radical chain reaction-dependent generation of oxidized phospholipid mediators
Authors: Iuchi Katsuya , Imoto Akemi , Kamimura Naomi , Nishimaki Kiyomi , Ichimiya Harumi , Yokota Takashi , Ohta Shigeo
Published: January 2016

We previously showed that H2 acts as a novel antioxidant to protect cells against oxidative stress. Subsequently, numerous studies have indicated the potential applications of H2 in therapeutic and preventive medicine. Moreover, H2 regulates various signal transduction pathways and the expression of many genes. However, the primary targets of H2 in the signal transduction pathways are unknown. Here, we attempted to determine how H2 regulates gene expression. In a pure chemical system, H2 gas (approximately 1%, v/v) suppressed the autoxidation of linoleic acid that proceeds by a free radical chain reaction and pure 1-palmitoyl-2-arachidonyl-sn-glycero-3-phosphocholine (PAPC), one of the major phospholipids, was autoxidized in the presence or absence of H2. H2 modified the chemical production of the autoxidized phospholipid species in the cell-free system. Exposure of cultured cells to the H2-dependently autoxidized phospholipid species reduced Ca2+ signal transduction and mediated the expression of various genes as revealed by comprehensive microarray analysis. In the cultured cells, H2 suppressed free radical chain reaction-dependent peroxidation and recovered the increased cellular Ca2+, resulting in the regulation of Ca2+-dependent gene expression. Thus, H2 might regulate gene expression via the Ca2+ signal transduction pathway by modifying the free radical-dependent generation of oxidized phospholipid mediators.
High-frequency chaotic dynamics enabled by optical phase-conjugation
Authors: Mercier Émeric , Wolfersberger Delphine , Sciamanna Marc
Published: January 2016

Wideband chaos is of interest for applications such as random number generation or encrypted communications, which typically use optical feedback in a semiconductor laser. Here, we show that replacing conventional optical feedback with phase-conjugate feedback improves the chaos bandwidth. In the range of achievable phase-conjugate mirror reflectivities, the bandwidth increase reaches 27% when compared with feedback from a conventional mirror. Experimental measurements of the time-resolved frequency dynamics on nanosecond time-scales show that the bandwidth enhancement is related to the onset of self-pulsing solutions at harmonics of the external-cavity frequency. In the observed regime, the system follows a chaotic itinerancy among these destabilized high-frequency external-cavity modes. The recorded features are unique to phase-conjugate feedback and distinguish it from the long-standing problem of time-delayed feedback dynamics.