bluuebunny/crossref_metadata_2025 huggingface dataset:
Modulation of the biliary expression of arylalkylamine N-acetyltransferase alters the autocrine proliferative responses of cholangiocytes in rats
Authors: Renzi Anastasia , DeMorrow Sharon , Onori Paolo , Carpino Guido , Mancinelli Romina , Meng Fanyin , Venter Julie , White Mellanie , Franchitto Antonio , Francis Heather , Han Yuyan , Ueno Yoshiyuki , Dusio Giuseppina , Jensen Kendal J. , Greene John J. , Glaser Shannon , Gaudio Eugenio , Alpini Gianfranco
Published: October 2012

Secretin stimulates ductal secretion by interacting with secretin receptor (SR) activating cyclic adenosine 3′,5′-monophosphate/cystic fibrosis transmembrane conductance regulator/chloride bicarbonate anion exchanger 2 (cAMP⇒CFTR⇒Cl−/HCO
Symbol
AE2) signaling that is elevated by biliary hyperplasia. Cholangiocytes secrete several neuroendocrine factors regulating biliary functions by autocrine mechanisms. Melatonin inhibits biliary growth and secretin-stimulated choleresis in cholestatic bile-duct–ligated (BDL) rats by interaction with melatonin type 1 (MT1) receptor through down-regulation of cAMP-dependent signaling. No data exist regarding the role of melatonin synthesized locally by cholangiocytes in the autocrine regulation of biliary growth and function. In this study, we evaluated the (1) expression of arylalkylamine N-acetyltransferase (AANAT; the rate-limiting enzyme for melatonin synthesis from serotonin) in cholangiocytes and (2) effect of local modulation of biliary AANAT expression on the autocrine proliferative/secretory responses of cholangiocytes. In the liver, cholangiocytes (and, to a lesser extent, BDL hepatocytes) expressed AANAT. AANAT expression and melatonin secretion (1) increased in BDL, compared to normal rats and BDL rats treated with melatonin, and (2) decreased in normal and BDL rats treated with AANAT Vivo-Morpholino, compared to controls. The decrease in AANAT expression, and subsequent lower melatonin secretion by cholangiocytes, was associated with increased biliary proliferation and increased SR, CFTR, and Cl−/HCO
Symbol
AE2 expression. Overexpression of AANAT in cholangiocyte cell lines decreased the basal proliferative rate and expression of SR, CFTR, and Cl−/HCO
Symbol
AE2 and ablated secretin-stimulated biliary secretion in these cells.

Conclusion
: Local modulation of melatonin synthesis may be important for management of the balance between biliary proliferation/damage that is typical of cholangiopathies. (Hepatology 2013)
The role of CCAAT enhancer-binding protein homologous protein in human immunodeficiency virus protease-inhibitor–induced hepatic lipotoxicity in mice
Authors: Wang Yun , Zhang Luyong , Wu Xudong , Gurley Emily C. , Kennedy Elaine , Hylemon Phillip B. , Pandak William M. , Sanyal Arun J. , Zhou Huiping
Published: October 2012

Human immunodeficiency virus (HIV) protease inhibitors (HIV PIs) are the core components of highly active antiretroviral therapy, which has been successfully used in the treatment of HIV-1 infection in the past two decades. However, benefits of HIV PIs are compromised by clinically important adverse effects, such as dyslipidemia, insulin resistance, and cardiovascular complications. We have previously shown that activation of endoplasmic reticulum (ER) stress plays a critical role in HIV PI–induced dys-regulation of hepatic lipid metabolism. HIV PI–induced hepatic lipotoxicity is closely linked to the up-regulation of CCAAT enhancer binding protein homologous protein (CHOP) in hepatocytes. To further investigate whether CHOP is responsible for HIV PI–induced hepatic lipotoxicity, C57BL/6J wild-type (WT) or CHOP knockout (CHOP−/−) mice or the corresponding primary mouse hepatocytes were used in this study. Both

in vitro

and

in vivo

studies indicated that HIV PIs (ritonavir and lopinavir) significantly increased hepatic lipid accumulation in WT mice. In contrast, CHOP−/− mice showed a significant reduction in hepatic triglyceride accumulation and liver injury, as evidenced by hematoxylin and eosin and Oil Red O staining. Real-time reverse-transcriptase polymerase chain reaction and immunoblotting data showed that in the absence of CHOP, HIV PI–induced expression of stress-related proteins and lipogenic genes were dramatically reduced. Furthermore, tumor necrosis factor alpha and interleukin-6 levels in serum and liver were significantly lower in HIV PI–treated CHOP−/− mice, compared to HIV PI–treated WT mice.

Conclusion
: Taken together, these data suggest that CHOP is an important molecular link of ER stress, inflammation, and hepatic lipotoxicity, and that increased expression of CHOP represents a critical factor underlying events leading to hepatic injury. (Hepatology 2013)
Inhibition of mammalian target of rapamycin aggravates the respiratory burst defect of neutrophils from decompensated patients with cirrhosis
Authors: Rolas Loïc , Makhezer Nesrine , Hadjoudj Soumeya , El-Benna Jamel , Djerdjouri Bahia , Elkrief Laure , Moreau Richard , Périanin Axel
Published: October 2012

Cirrhosis is commonly accompanied by impaired defense functions of polymorphonuclear leucocytes (PMNs), increased patient susceptibility to infections, and hepatocellular carcinoma (HCC). PMN antimicrobial activity is dependent on a massive production of reactive oxygen species (ROS) by nicotinamide adenine dinucleotide phosphate (NADPH) 2 (NADPH oxidase 2; NOX2), termed respiratory burst (RB). Rapamycin, an antagonist of mammalian target of rapamycin (mTOR), may be used in the treatment of HCC and in transplanted patients. However, the effect of mTOR inhibition on the PMN RB of patients with cirrhosis remains unexplored and was studied here using the bacterial peptide, formyl-Met-Leu-Phe (fMLP), as an RB inducer. fMLP-induced RB of PMN from patients with decompensated alcoholic cirrhosis was strongly impaired (30%-35% of control) as a result of intracellular signaling alterations. Blocking mTOR activation (phospho-S2448-mTOR) with rapamycin further aggravated the RB defect. Rapamycin also inhibited the RB of healthy PMNs, which was associated with impaired phosphorylation of the NOX2 component, p47

phox

(phox: phagocyte oxidase), on its mitogen-activated protein kinase (MAPK) site (S345) as well as a preferential inhibition of p38-MAPK relative to p44/42-MAPK. However, rapamycin did not alter the fMLP-induced membrane association of p47

phox

and p38-MAPK in patients' PMNs, but did prevent their phosphorylation at the membranes. The mTOR contribution to fMLP-induced RB, phosphorylation of p47

phox

and p38-MAPK was further confirmed by mTOR knockdown in HL-60 cells. Finally, rapamycin impaired PMN bactericidal activity, but not bacterial uptake.

Conclusion
: mTOR significantly up-regulates the PMN RB of patients with cirrhosis by p38-MAPK activation. Consequently, mTOR inhibition by rapamycin dramatically aggravates their PMN RB defect, which may increase patients' susceptibility to infection. Thus, concerns should be raised about the use of rapamycin in immuno-depressed patients. (Hepatology 2013)
Gold(I)‐Catalyzed Cyclodehydration Enabled by the Triisopropylsilyl Group: A Synthetically Versatile Methodology
Authors: Usanov Dmitry L. , Naodovic Marina , Brasholz Malte , Yamamoto Hisashi
Published: October 2012

Introduction of a triisopropylsilyl group into allyl and allenyl carbinols greatly enhances the efficiency of gold(I)‐catalyzed cyclodehydration, which can provide rapid access to a library of various compounds including 1H‐indenes (Table 2 and Scheme 5), benzofulvenes (Table 3), indan‐2‐ones (Scheme 2), fulvenes (Table 4), cyclopentadienes (Table 4), 5H‐dibenzo[a,c][7]annulenes (Scheme 6) and dibenzosuberones (Scheme 6). The developed method enables unprecedented product generality for several classes of cyclodehydration reactions, which is particularly notable for the preparation of 1H‐indenes. The first synthesis of non‐benzo‐fused fulvenes via cyclodehydration of allenyl vinyl carbinols could be accomplished. The protocol is remarkable for mild conditions, operational convenience, and easy access to starting materials.
dl‐Ribose Crystal Structures: the GlassCrystal Transformation
Authors: Zandomeneghi Giorgia , Schweizer W. Bernd , Gilmour Ryan , Meier Beat H. , Dunitz Jack D.
Published: October 2012

We present two crystal structures of dl‐ribose and a first glimpse into the mechanism of the glasscrystal transformation of sugars.
C1‐Symmetric Bicyclo[2.2.2]octa‐2,5‐diene (bod*) Ligands in Rhodium‐Catalyzed Asymmetric 1,4‐Addition of Arylboronic Acids to Enones and 1,2‐Addition to N‐[(4‐Nitrophenyl)sulfonyl]imines
Authors: Brönnimann Rebecca , Chun Sothys , Marti Roger , Abele Stefan
Published: October 2012

A set of ten C1‐symmetric chiral bicyclo[2.2.2]octa‐2,5‐dienes (bod*) 2 (Fig. 1) were tested as ligands in Rh‐catalyzed arylation reactions. The 1,4‐addition of arylboronic acids to cyclohex‐2‐en‐1‐one, cyclopent‐2‐en‐1‐one, and tert‐butyl cinnamate proceeded smoothly with excellent enantioselectivities (up to 99% ee; Tables 1–3). The challenging 1,2‐addition of triphenylboroxine to N‐[(4‐nitrophenyl)sulfonyl]imines yielded the product in high yield and in good enantioselectivity (up to 92% ee; Table 4). Generally, the use of C1‐symmetric chiral bod* ligands bearing bulky substituents resulted in lower enantioselectivities, whereas several electron‐poor and electron‐rich bod* ligands gave higher enantioselectivities than the benchmark ligands reported in literature.
Cyclization of (2‐Alkenylphenyl)carbonyl Compounds to Polycyclic Arenes Catalyzed by Copper(II) Trifluoromethanesulfonate or Trifluoromethanesulfuric Acid
Authors: Liu Wei‐Min , Tnay Ya Lin , Gan Kian Ping , Liu Zhen‐Hong , Tyan Wan Huei , Narasaka Koichi
Published: October 2012

Various polycyclic arenes, such as naphthalenes, tetrahydroantharacenes, tetrahydrotetracenes, dihydropentacenes, and dihydropentaphenes are prepared from 2‐alkenylphenyl ketones and aldehydes by the catalytic use of copper(II) trifluoromethanesulfonate (Cu(OTf)2) or trifluoromethanesulfuric acid (TfOH).
Secondary Amine‐Catalyzed Asymmetric γ‐Alkylation of α‐Branched Enals via Dienamine Activation
Authors: Silvi Mattia , Cassani Carlo , Moran Antonio , Melchiorre Paolo
Published: October 2012

The direct and enantioselective γ‐alkylation of α‐substituted α,β‐unsaturated aldehydes proceeding under dienamine catalysis is described. We have found that the Seebach modification of the diphenyl‐prolinol silyl ether catalyst in combination with saccharin as an acidic additive promotes an SN1 alkylation pathway, while ensuring complete γ‐site selectivity and a high stereocontrol. Theoretical and spectroscopic investigations have provided insights into the conformational behavior of the covalent dienamine intermediate derived from the condensation of 2‐methylpent‐2‐enal and the chiral amine. Implications for the mechanism of stereoinduction are discussed.
A Total Synthesis of Aliskiren
Authors: Nam Gyeok , Ko Soo Y.
Published: October 2012

A total synthesis of aliskiren (20) was accomplished. A key in our synthesis was to use the symmetric trans‐cisoid‐trans‐bis‐lactone 1 as a precursor. It was expediently prepared by three different routes (Scheme 2). Appending the end groups and functional group transformations completed the synthesis (Scheme 3).
Synthesis of (1α)‐1,25‐Dihydroxyvitamin D3 with a β‐Positioned Seven‐Carbon Side Chain at C(12)
Authors: Carballa Diego M. , Rumbo Antonio , Torneiro Mercedes , Maestro Miguel , Mouriño Antonio
Published: October 2012

A convergent synthesis of an analogue of (1α)‐1,25‐dihydroxyvitamin D3 (1b) with a C7 side chain at C(12), i.e., of 5 (Fig.), is described. A key step of the synthesis is the assembly of the triene system by a PdII‐catalyzed ring closure of an enol triflate (‘bottom’ fragment) followed by coupling of the resulting PdII intermediate with an alkenylboronate (‘upper’ fragment) (Scheme 2). The synthetic strategy allows isotopic labelling at the end of the synthesis.
Kinetic Resolution of Racemic Secondary Benzylic Alcohols by the Enantioselective Esterification Using Pyridine‐3‐carboxylic Anhydride (3‐PCA) with Chiral Acyl‐Transfer Catalysts
Authors: Shiina Isamu , Nakata Kenya , Ono Keisuke , Mukaiyama Teruaki
Published: October 2012

Pyridine‐3‐carboxylic anhydride (3‐PCA) was found to function as an efficient coupling reagent for the preparation of carboxylic esters from various carboxylic acids with alcohols under mild conditions by a simple experimental procedure. This novel condensation reagent 3‐PCA was applicable not only for the synthesis of achiral carboxylic esters catalyzed by 4‐(dimethylamino)pyridine (DMAP) but also for the production of chiral carboxylic esters by the combination of chiral nucleophilic catalyst, such as tetramisole (=2,3,5,6‐tetrahydro‐6‐phenylimidazo[2,1‐b][1,3]thiazole) derivatives. An efficient kinetic resolution of racemic benzylic alcohols with achiral carboxylic acids was achieved by using 3‐PCA in the presence of (R)‐benzotetramisole ((R)‐BTM), and a variety of optically active carboxylic esters were produced with high enantiomeric excesses by this new chiral induction system without using a tertiary amine.
A Hydrogen Chloride‐Free Pinner Reaction Promoted by Lewis Acids
Authors: Pfaff Dominik , Nemecek Gregor , Podlech Joachim
Published: October 2012

A hydrogen chloride‐free variation of the Pinner reaction was developed, in which alcohols react with carbonitriles to furnish carboxylates. Best results were achieved with aliphatic alcohols, and aliphatic or benzylic nitriles in the presence of 2 equiv. of trimethylsilyl triflate (Me3SiOTf). With these substrates, yields exceeding 80% were achieved. A strictly neutral variation of this protocol is possible, when 1 equiv. of Et3N is added to the reaction mixture.
A Manifold Three‐Step Synthetic Route to Polycyclic Annulated Hydantoins via Cyclic Imines
Authors: Brockmeyer Fabian , Kröger Denis , Stalling Timo , Ullrich Pasqual , Martens Jürgen
Published: October 2012

A new three‐step synthetic pathway to generate polycyclic annulated hydantoins via rarely investigated heterocyclic imines is described. This procedure includes a one‐pot reaction forming imines as precursor structures (e.g., Asinger reaction), followed by an Ugi reaction to build up a bisamide structure that allows a ring‐closing reaction to the targeted hydantoins via substitution. This pathway leads to a multiplicity of substances with a potential pharmacological activity.
Standards, Policy Paradoxes, and the New Literacy Studies: A Call to Professional Political Action
Authors: Burns Leslie David
Published: October 2012

In this commentary, the author uses New Literacy Studies theories to examine the Common Core State Standards Initiative (CCSSI). Through analysis and critique of the CCSSI and related reform efforts underway in the United States, the author discusses how policy mandates can and have resulted in paradoxes. Corporate discourses of effectiveness and bureaucracy (intentionally or otherwise) undercut the use of research‐based knowledge for literacy education reform. Consequently, professional literacy educators are positioned to subordinate themselves in the governance of their own profession despite statements by reform leaders that they must have the autonomy to make expert decisions that help students learn and practice literacy in contemporary society. The author calls for organizations like the International Reading Association to act politically and strategically, create knowledge, mobilize members, and educate stakeholders so that policy reforms become more equitable, just, and successful for the ends they are intended to meet.
The Proverbial Rock and Hard Place: The Realities and Risks of Teaching in a World of Multiliteracies, Participatory Culture, and Mandates
Authors: Jacobs Gloria E.
Published: October 2012

This column revisits the concept of multiliteracies as originally proposed by the New London Group. Particular attention is given to the saliency of multiliteracies in light of the technological and educational policy changes and pressures that have occurred since the mid 1990s. The relationship of multiliteracies to participatory culture and the ethos of Web 2.0 is considered. and a brief review of four recent studies provide insight into how teachers can use multiliteracies to prepare students for critical engagement in the world while supporting literacy development. It is suggested that despite political pressures to narrow curriculum to meet accountability measures, ignoring the promise of multiliteracies places students at high risk for further marginalization.
Read, Flip, and Write!
Authors: Matson Sandra F.
Published: October 2012

This column features essays written by current middle school and high school teachers, media specialists, librarians, literacy coaches, curriculum specialists, administrators, preservice teachers, teacher educators, and adolescent and adult learners. They highlight diverse perspectives on teaching and/or learning with literacies to inspire reader reflection.
What's in a Word? Using Content Vocabulary to Generate Growth in General Academic Vocabulary Knowledge
Authors: Flanigan Kevin , Templeton Shane , Hayes Latisha
Published: October 2012

The role of vocabulary knowledge in supporting students’ comprehension and understanding of their content‐area reading is critical. This article explores how content‐area teachers can help students become aware of, understand, and apply generative knowledge about English words to grow and develop their vocabularies. Generative vocabulary instruction builds on the fact that most words in English are formed by combining meaningful word parts. Teachers can address this generative aspect directly, modeling and guiding students’ developing understanding of this productive aspect of words. A generative emphasis supports more efficient and engaging vocabulary learning of both content vocabulary and general academic vocabulary. Guidelines for teaching vocabulary generatively are provided, as well as effective resources for supporting teachers’ selection of and information about words and word parts.
Teachers’ Enactment of Content Literacy Strategies in Secondary Science and Mathematics Classes
Authors: Adams Anne E. , Pegg Jerine
Published: October 2012

The incorporation of literacy strategies into content area instruction has been proposed as an effective way of improving student learning in the content areas. However, few studies have examined how teachers incorporate content literacy strategies into their instruction and the specific nature of implementation. As part of an ongoing professional development project on content literacy in secondary science and mathematics classes, we conducted a qualitative inquiry which examined the nature of teachers’ enactment of specific content literacy strategies through the analysis of classroom observations, teacher lesson plans, and teachers’ online discussions. Results show that teachers were using content literacy strategies; however, the nature of their enactment of these strategies varied in ways that influenced the learning outcomes. In this paper we describe a framework for characterizing these differences in enactment, provide examples of these variations, and discuss implications for enacting literacy strategies in these different ways.
Synthesis and surface properties of polyurethane end‐capped with hybrid hydrocarbon/fluorocarbon double‐chain phospholipid
Authors: Li Jiehua , Zhang Yi , Yang Jian , Tan Hong , Li Jianshu , Fu Qiang
Published: October 2012

To improve hemocompatibility of biomedical polyurethanes (PUs), a series of new fluorinated phospholipid end‐capped polyurethanes (FPCPUs) as blending PU additives were designed and synthesized using diphenyl methane diisocyanate and 1,4‐butanediol as hard segment, poly(tetramethylene glycol), polypropylene glycol, polycarbonate diols, and polyethylene glycol as soft segments, respectively, aminofunctionalized hybrid hydrocarbon/fluorocarbon double‐chain phospholipid as end‐capper. The bulk structures and surface properties of the obtained FPCPUs were fully characterized by 1H NMR, Fourier transform infrared, gel permeation chromatography, X‐ray photoelectron spectroscopy, differential scanning calorimetry, atomic force microscopy, and water contact angle measurement. It was found that the phosphatidylcholine groups could enrich on the surfaces and subsurfaces with the help of the fluorocarbon chains and self‐assemble into mimic biomembrane on these polymer surfaces. These surfaces could effectively suppress fibrinogen adsorption, as evaluated by enzyme‐linked immunosorbent assay method. Our work indicates that the FPCPUs should be one of the most potential modified additives for enhancing hemocompatibility of traditional medical PUs. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Spatial variability of nitrous oxide emissions in an unmanaged old‐growth beech forest
Authors: Jungkunst Hermann F. , Bargsten Anika , Timme Marc , Glatzel Stephan
Published: October 2012

Nitrous oxide (N2O) is a high‐impact greenhouse gas. Due to the scarcity of unmanaged forests in Central Europe, its long‐term natural background emission level is not entirely clear. We measured soil N2O emissions in an unmanaged, old‐growth beech forest in the Hainich National Park, Germany, at 15 plots over a 1‐year period. The average annual measured N2O flux rate was (0.49 ± 0.44) kg N ha–1 y–1. The N2O emissions showed background‐emission patterns with two N2O peaks. A correlation analysis shows that the distance between plots (up to 380 m) does not control flux correlations. Comparison of measured data with annual N2O flux rates obtained from a standard model (Forest‐DNDC) without site‐specific recalibration reveals that the model overestimates the actual measured N2O flux rates mainly in spring. Temporal variability of measured N2O flux was better depicted by the model at plots with high soil organic C (SOC) content. Modeled N2O flux rates were increased during freezing only when SOC was > 0.06 kg C kg–1. The results indicate that the natural background of N2O emissions may be lower than assumed by most approaches.
Double Hydrogen‐Bonding pH‐Sensitive Hydrogels Retaining High‐Strengths Over a Wide pH Range
Authors: Gao Han , Wang Ning , Hu Xiufeng , Nan Wenjing , Han Yanjiao , Liu Wenguang
Published: October 2012

Traditional pH‐sensitive hydrogels inevitably suffer strength deterioration while the responsive weak acid or base groups are in the ionized state. In this study, we report on a facile approach to fabricate a novel pH‐sensitive high‐strength hydrogel from copolymerization of two hydrogen‐bonding motif‐containing monomers, 3‐acrylamidophenylboronic acid and 2‐vinyl‐4,6‐diamino‐1,3,5‐triazine with a crosslinker N,N‐methylenebisacrylamide through hydrophilic optimization of the comonomer oligo(ethylene glycol) methacrylate. The double hydrogen bonding hydrogel exhibits both high tensile and compressive strengths over a broad pH range due to the unique ability to maintain at least one type of hydrogen‐bonding crosslink over the whole course of pH change.
Measuring self‐efficacy to deal with infertility: Psychometric properties and confirmatory factor analysis of the portuguese version of the infertility self‐efficacy scale
Authors: Galhardo Ana , Cunha Marina , Pinto‐Gouveia José
Published: October 2012

This study explores the psychometric properties and factor structure of the Portuguese version of the Infertility Self‐Efficacy Scale (ISE‐P), using translation and back‐translation of the original version; principal component analysis; confirmatory factor analysis (CFA); and internal consistency, and test–retest reliability analyses. A total of 287 participants (156 women and 131 men) seeking medical treatment were recruited from public and private fertility centers. CFA revealed that the single‐component model fit the data well. The instrument showed excellent internal consistency, good test–retest reliability, and correlations with other mental health measures suggesting good convergent and discriminant validity. In conclusion, The ISE‐P is a valid and reliable Portuguese‐language measure of perceived self‐efficacy to cope with infertility. © 2012 Wiley Periodicals, Inc. Res Nurs Health 36:65–74, 2013
Missing a strategic marketing trick? The use of online social networks by UK charities
Authors: Quinton Sarah , Fennemore Paul
Published: October 2012

This paper explores the use of online social networks in the charity sector. Twelve major UK charities from a range of sectors and three digital marketing agencies were selected to provide rich interview data on the current adoption of online social networks by UK charities. The empirical findings illustrate the diverse drivers in adopting online social networks including regaining control of a brand, external pressures and gaining new audiences. Levels of usage differed significantly and the resistors consistently cited were the lack of skills and resources. The strategic marketing implications for the development of online social networks are also outlined for the UK charity market. The value provided by this paper stems from exploring the organisational perspective rather than the consumer experience of contributing to social networks, within a context which is often overlooked, the charity sector.

Copyright © 2012 John Wiley & Sons, Ltd.
Optikdesign mit maßgeschneiderten Freiformflächen
Authors: Ries Harald
Published: October 2012

Beleuchtungsoptik lässt sich im Gegensatz zu abbildenden optischen Systemen exakt berechnen. Als Ergebnis erhält der Designer im Allgemeinen Freiformflächen, die mit CAM direkt als Prototyp oder Spritzgussform realisiert werden können.
Die virtuelle Welt real sehen
Authors: Klavehn Andreas , Wierse Andreas
Published: October 2012

Die 3D Multimediabrille cinemizer OLED der Carl Zeiss AG, Oberkochen ermöglicht zusammen mit der Virtual Reality (VR) Software‐Technologie der Visenso GmbH, Stuttgart eine Simulation der realen 3D Wahrnehmung für innovative Anwendungen in Industrie und Freizeit. Sie reichen heute vom Engineering über das Marketing bis hin zu Aus‐ und Weiterbildung und sind inzwischen auch ultramobil verfügbar.
Megapixel‐Wärmebilder mit 1280 × 1024 Pixeln
Authors: Sarfels Joachim
Published: October 2012

Ingenieure und Wissenschaftler aller Disziplinen erleben eine Revolution von Auflösung und Geschwindigkeit in der Infrarotkameratechnik: Qualitativ hochwertige Wärmebilder mit einer Auflösung von 1280 × 1024 Pixeln zeigen selbst minimale thermische Anomalien und kleinste Details.
Cortical maturation in fetuses referred for ‘isolated’ mild ventriculomegaly: a longitudinal ultrasound assessment
Authors: Miguelote R. F. , Vides B. , Santos R. F. , Palha J. A. , Matias A. , Sousa N.
Published: October 2012

Objectives

To compare cortical maturation between fetuses with isolated mild ventriculomegaly (IMV) and healthy fetuses, and to explore its potential prognostic value in IMV.

Methods

This prospective study quantified cortical maturation by ultrasound in 24 fetuses with IMV and 46 healthy fetuses. Depth and grading the developmental pattern of the parieto‐occipital fissure (POF), calcarine fissure (CF) and sylvian fissure, and grading the Sylvian fissure operculization at 23–25, 27–28 and 31–32 weeks gestation were determined.

Results

At 23–25 and 27–28 gestational weeks, POF and CF mean depths were statistically lower in the IMV group. The POF and CF depth distribution had a normal distribution in the control group but displayed a bimodal distribution in the IMV group. IMV with progression of ventricular dilatation showed mean depth of CF lower than IMV in which ventriculomegaly regressed or remained stable. The sensitivity, specificity, positive predictive value and negative predictive value of a CF depth below the fifth percentile to predict progression of ventricular dilatation were, at 28 weeks, 100%, 88%, 67% and 100%, respectively.

Conclusions

Cortical fissure assessment by ultrasound allowed the differentiation of a subgroup of IMV fetuses with a higher risk of progression of ventricular dilatation. © 2012 John Wiley & Sons, Ltd.
Modification of clarified polypropylene by oxygen plasma to improve the adhesion of thin amorphous hydrogenated carbon films deposited by plasma enhanced chemical vapor deposition
Authors: Aguiar P.H.L. , Oliveira É.C. , Cruz S.A.
Published: October 2012

Despite having many potential applications, polypropylene (PP) has limitations that may make its application difficult when there is a requirement for high transparency and low‐gas permeability. In this context, studies have been reported about the usage of amorphous hydrogenated carbon thin films to act as a functional barrier in polymer packaging. Therefore, this current work evaluated the modification on the surface‐clarified polypropylene (cPP) by oxygen plasma to improve the adhesion of amorphous hydrogenated carbon films (a‐C:H) deposited by plasma‐enhanced chemical vapor deposition. However, some applications of these films are limited by the presence of microdefects and low adhesion when applied onto polymeric substrates. So, the surface of cPP was treated with oxygen plasma, and the adhesion between the a‐C:H films and cPP was evaluated. Contact angle goniometry, infrared spectroscopy, and atomic force microscopy were used to analyze chemical and morphological changes, respectively. Tape test and scanning electron microscopy were used to evaluate the adhesion of a‐C:H films deposited on a cPP surface. The results showed that the pretreatment increased the adhesion between the cPP and amorphous hydrogenated carbon, which is crucial for the application of these films in packaging with high‐barrier properties. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers
Photovoltaics and zero energy buildings: a new opportunity and challenge for design
Authors: Scognamiglio Alessandra , Røstvik Harald N.
Published: October 2012

Starting from the end of 2020, all new buildings will have to be Nearly Zero Energy Buildings (Nearly ZEBs—ED 2010/31/EU recast). This new ‘energy paradigm’ might be a revolution for architecture and for Photovoltaics (PV) too, but there are both cultural and technical obstacles to overcome. There is a need to re‐think the way buildings are designed (integrating renewables for being ZE). There is a need to re‐think the way PV is designed in buildings. PV will be gaining an increasing relevance in the ZEBs design, thanks to its features and potentialities (suitability for any kind of energy demand of the building, easiness of building integration, cost). In a ZEB scenario, PV is very suitable for generating energy, ‘on site’ and ‘at site’; this enlarges the perspective of use of PV from the architectural scale to a wider scale, including the space close to the building or even to the urban and landscape scale. In such a new context, the existing research on the relationships between PV and architecture, focusing mainly on the way the PV components are used in relation to the envelope (Building‐integrated PV/Building‐added (Attached) PV), is no longer sufficient. The authors envision possible formal results, opportunities and challenges, for the use of PV in ZEBs, as well as new research issues for the future relationships between PV and ZEBs from the architecture and landscape design point of view. Copyright © 2012 John Wiley & Sons, Ltd.
Temperature dependent phase behavior of PNIPAM microgels in mixed water/methanol solvents
Authors: Kojima Hiroyuki , Tanaka Fumihiko , Scherzinger Christine , Richtering Walter
Published: October 2012

Temperature dependent phase behavior of poly(N‐isopropylacylamide) (PNIPAM) microgels in water/methanol mixtures of different composition was studied with dynamic light scattering (DLS) and small‐angle neutron scattering (SANS). Using DLS, it is possible to measure the diffusion coefficient, and thus the size of particles exactly and directly; the variation of the phase transition temperature in the different solvents is also easy to detect by this method. With SANS measurements in D2O/MeOD mixtures, some of the DLS results were confirmed. Moreover, SANS measurements give valuable information on the particle structure in different solvents. The experiments were compared with the theory of competitive hydration introduced by Tanaka et al. We found a good agreement of theory and experiment, and obtained the theoretical predictions: around the transition temperature, the composition of the bound methanol along the chains is higher than that of the outer solution, while the whole methanol composition inside the gel is lower. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym. Phys. 2013, 51, 1100–1111
Correlating structure and function during the evolution of fibrinogen‐related domains
Authors: Doolittle Russell F. , McNamara Kyle , Lin Kevin
Published: October 2012

Fibrinogen‐related domains (FReDs) are found in a variety of animal proteins with widely different functions, ranging from non‐self recognition to clot formation. All appear to have a common surface where binding of one sort or other occurs. An examination of 19 completed animal genomes—including a sponge and sea anemone, six protostomes, and 11 deuterostomes—has allowed phylogenies to be constructed that show where various types of FReP (proteins containing FReDs) first made their appearance. Comparisons of sequences and structures also reveal particular features that correlate with function, including the influence of neighbor‐domains. A particular set of insertions in the carboxyl‐terminal subdomain was involved in the transition from structures known to bind sugars to those known to bind amino‐terminal peptides. Perhaps not unexpectedly, FReDs with different functions have changed at different rates, with ficolins by far the fastest changing group. Significantly, the greatest amount of change in ficolin FReDs occurs in the third subdomain (“P domain”), the very opposite of the situation in most other vertebrate FReDs. The unbalanced style of change was also observed in FReDs from non‐chordates, many of which have been implicated in innate immunity.
Cross‐reactivity of a human IgG1 anticitrullinated fibrinogen monoclonal antibody to a citrullinated profilaggrin peptide
Authors: Trier Nicole Hartwig , Leth Maria Louise , Hansen Paul Robert , Houen Gunnar
Published: October 2012

Rheumatoid arthritis (RA) is the most common autoimmune rheumatic disease. It is characterized by persistent joint inflammation, resulting in loss of joint function, morbidity and premature mortality. The presence of antibodies against citrullinated proteins is a characteristic feature of RA and up to 70% of RA patients are anticitrullinated protein antibody (ACPA) positive. ACPA responses have been widely studied and are suggested to be heterogeneous, favoring antibody cross‐reactivity to citrullinated proteins. In this study, we examined factors that may influence cross‐reactivity between a commercial human anticitrullinated fibrinogen monoclonal antibody and a citrullinated peptide. Using a citrullinated profilaggrin sequence (HQCHQEST‐ Cit‐GRSRGRCGRSGS) as template, cyclic and linear truncated peptide versions were tested for reactivity to the monoclonal antibody. Factors such as structure, peptide length and flanking amino acids were found to have a notable impact on antibody cross‐reactivity. The results achieved contribute to the understanding of the interactions between citrullinated peptides and ACPA, which may aid in the development of improved diagnostics of ACPA.
SiO2/MgO coated multiwalled carbon nanotubes in polymer composites
Authors: Nemeth Krisztian , Reti Balazs , Posa Mark , Belina Karoly , Hernadi Klara
Published: October 2012

The aim of this work was to develop a talc‐like inorganic coating on the surface of the multiwalled carbon nanotubes (MWCNTs) to facilitate their mixing into the polypropylene and polyethylene matrix. Precursor compounds such as MgCl2 · 6H2O, Mg(NO3)2 · 6H2O, MgO2C4H10 and tetraethyl‐orthosilicate (TEOS) were used to cover the surface of the MWCNTs. As prepared, coverages and polymer composites were characterized by transmission electron microscopy and X‐ray diffraction techniques.
Photoinduced currents in graphene and carbon nanotubes
Authors: Ivchenko E. L.
Published: October 2012

The paper overviews experimental and theoretical studies of photogalvanic effects (PGEs) induced in graphene and carbon nanotubes (CNs) by polarized electromagnetic radiation. The following items are discussed: the helicity‐dependent photon‐drag and edge electric currents in graphene sheets, the circular PGEs in asymmetric graphene superlattices and chiral CNs, and pure valley currents generated in graphene by the interband absorption of linearly polarized light.
P‐doped random C20 fullerite – model structure for fullerene‐like CPx
Authors: Czigány Zsolt
Published: October 2012

Carbon‐based amorphous and fullerene‐like (FL) thin films have a great potential due to their mechanical resiliency. TEM investigation and interpretation of results from FL structures embedded in bulk phases is not straightforward. Here, a model is presented for description of the structure of FL‐CP0.1 thin films and to describe all the rings in the electron diffraction pattern in a self‐consistent way. The model structure consists of random close‐packed and P‐doped C20 clusters resembling a kind of amorphous fullerite (crystals of fullerene cages). The 10% P doping was implemented by creating C18P2 cages by replacing two C atoms by P in the C20 cage. The simulated electron scattering is in agreement with the experimental electron diffraction pattern and reproduces all the observed diffuse diffraction rings of FL‐CP0.1 at ∼1.6, ∼2.6, and ∼5.9 Å. Simulation of HRTEM images confirmed the amorphous appearance of this nanostructured material.

magnified image

A cluster of P‐doped random close‐packed C20 fullerite (right) and its calculated electron diffraction (left) for different average cluster size (expressed in number of atoms).
Comment on “density and physical current density functional theory” by Xiao‐Yin Pan and Viraht Sahni
Authors: Vignale Giovanni , Ullrich Carsten A. , Capelle Klaus
Published: October 2012

A recent paper by Xiao‐Yin Pan and Viraht Sahni [Int. J. Quant. Chem. 110, 2833 (2010)] claims that current density functional theory should be based on the physical current density rather than the paramagnetic current density, as in the standard Vignale‐Rasolt formulation. In this comment we show that the claims in the paper by Pan and Sahni are erroneous. © 2012 Wiley Periodicals, Inc.
Theoretical computation of low‐lying electronic states of HCNS: A CASPT2 study
Authors: Kong Chui‐Peng , Zhao Zeng‐Xia , Zhang Hong‐Xing
Published: October 2012

Complete active space self‐consistent field (CASSCF) and complete active space second‐order perturbation theory (CASPT2) calculations in conjunction with the aug‐cc‐pVTZ basis set have been used to investigate the low‐lying electronic states of thiofulminic acid (HCNS), HCNS+, and HCNS−. The result of geometry optimization using CASPT2/aug‐cc‐pVTZ shows that theoretically determined geometric parameters and harmonic vibrational frequencies for the HCNS ground state X1Σ+(X1A′) are in agreement with previous studies. The ionization energies, the electron affinity energies, the adiabatic excitation energies, and vertical excitation energies have been calculated and the corresponding cation and anion states are identified. By calculating adiabatic electron affinity, the states of HCNS− have been identified to contain both π orbital states (X2A′ and 12A″) and dipole‐bond states (14A′ and 14A″). © 2012 Wiley Periodicals, Inc.
Severity of bias of a simple estimator of the causal odds ratio in Mendelian randomization studies
Authors: Harbord Roger M. , Didelez Vanessa , Palmer Tom M. , Meng Sha , Sterne Jonathan A.C. , Sheehan Nuala A.
Published: October 2012

Mendelian randomization studies estimate causal effects using genetic variants as instruments. Instrumental variable methods are straightforward for linear models, but epidemiologists often use odds ratios to quantify effects. Also, odds ratios are often the quantities reported in meta‐analyses. Many applications of Mendelian randomization dichotomize genotype and estimate the population causal log odds ratio for unit increase in exposure by dividing the genotype‐disease log odds ratio by the difference in mean exposure between genotypes. This ‘Wald‐type’ estimator is biased even in large samples, but whether the magnitude of bias is of practical importance is unclear. We study the large‐sample bias of this estimator in a simple model with a continuous normally distributed exposure, a single unobserved confounder that is not an effect modifier, and interpretable parameters. We focus on parameter values that reflect scenarios in which we apply Mendelian randomization, including realistic values for the degree of confounding and strength of the causal effect. We evaluate this estimator and the causal odds ratio using numerical integration and obtain approximate analytic expressions to check results and gain insight. A small simulation study examines finite sample bias and mild violations of the normality assumption. For our simple data‐generating model, we find that the Wald estimator is asymptotically biased with a bias of around 10% in fairly typical Mendelian randomization scenarios but which can be larger in more extreme situations. Recently developed methods such as structural mean models require fewer untestable assumptions and we recommend their use when the individual‐level data they require are available. The Wald‐type estimator may retain a role as an approximate method for meta‐analysis based on summary data. Copyright © 2012 John Wiley & Sons, Ltd.
TGF-β-Superfamily Signaling Regulates Embryonic Stem Cell Heterogeneity: Self-Renewal as a Dynamic and Regulated Equilibrium
Authors: Galvin-Burgess Katherine E. , Travis Emily D. , Pierson Kelsey E. , Vivian Jay L.
Published: October 2012

Embryonic stem cells dynamically fluctuate between phenotypic states, as defined by expression levels of genes such as Nanog, while remaining pluripotent. The dynamic phenotype of stem cells is in part determined by gene expression control and dictated by various signaling pathways and transcriptional regulators. We sought to define the activities of two TGF-β-related signaling pathways, bone morphogenetic protein (BMP) and Nodal signaling, in modulating mouse embryonic stem (ES) cell heterogeneity in undifferentiated culture conditions. Both BMP and Nodal signaling pathways were seen to be active in distinct Nanog subpopulations, with subtle quantitative differences in activity. Pharmacological and genetic modulation of BMP or Nodal signaling strongly influenced the heterogeneous state of undifferentiated ES cells, as assessed by dynamic expression of Nanog reporters. Inhibition of Nodal signaling enhanced BMP activity, which through the downstream target Id factors, enhanced the capacity of ES cells to remain in the Nanog-high epigenetic state. The combined inhibition of Nodal and BMP signaling resulted in the accumulation of Nanog-negative cells, even in the presence of LIF, uncovering a shared role for BMP and Nodal signaling in maintaining Nanog expression and repression of differentiation. These results demonstrate a complex requirement for both arms of TGF-β-related signaling to influence the dynamic cellular phenotype of undifferentiated ES cells in serum-based media, and that differing subpopulations of ES cells in heterogeneous culture have distinct responses to these signaling pathways. Several pathways, including BMP, Nodal, and FGF signaling, have important regulatory function in defining the steady-state distribution of heterogeneity of stem cells.
Concise Review: The Evolution of human pluripotent stem cell culture: From feeder cells to synthetic coatings
Authors: Villa-Diaz L.G. , Ross A.M. , Lahann J. , Krebsbach P.H.
Published: October 2012

Current practices to maintain human pluripotent stem cells (hPSCs), which include induced pluripotent stem cells and embryonic stem cells, in an undifferentiated state typically depend on the support of feeder cells such as mouse embryonic fibroblasts (MEFs) or an extracellular matrix such as Matrigel. Culture conditions that depend on these undefined support systems limit our ability to interpret mechanistic studies aimed at resolving how hPSCs interact with their extracellular environment to remain in a unique undifferentiated state and to make fate-changing lineage decisions. Likewise, the xenogeneic components of MEFs and Matrigel ultimately hinder our ability to use pluripotent stem cells to treat debilitating human diseases. Many of these obstacles have been overcome by the development of synthetic coatings and bioreactors that support hPSC expansion and self-renewal within defined culture conditions that are free from xenogeneic contamination. The establishment of defined culture conditions and synthetic matrices will facilitate studies to more precisely probe the molecular basis of pluripotent stem cell self-renewal and differentiation. When combined with three-dimensional cultures in bioreactors, these systems will also enable large-scale expansion for future clinical applications.
mTORC1 and mTORC2 Play Different Roles in the Functional Survival of Transplanted Adipose-Derived Stromal Cells in Hind Limb Ischemic Mice Via Regulating Inflammation In Vivo
Authors: Fan Weiwei , Cheng Kang , Qin Xing , Narsinh Kazim H. , Wang Shenxu , Hu Sijun , Wang Yabin , Chen Yundai , Wu Joseph C. , Xiong Lize , Cao Feng
Published: October 2012

Poor cell survival severely limits the beneficial effects of stem cell therapy for peripheral arterial disease (PAD). This study was designed to investigate the role of mammalian target of rapamycin (mTOR) in the survival and therapeutic function of transplanted murine adipose-derived stromal cells (mADSCs) in a murine PAD model. mADSCs (1.0 × 107) were isolated from dual-reporter firefly luciferase and enhanced green fluorescent protein-positive transgenic mice, intramuscularly implanted into the hind limb of C57BL/6 mice after femoral artery ligation/excision, and monitored using noninvasive bioluminescence imaging (BLI). Although engrafted mADSCs produced antiapoptotic/proangiogenic effects in vivo by modulating the inflammatory and angiogenic cytokine response involving the mTOR pathway, longitudinal BLI revealed progressive death of post-transplant mADSCs within ∼4 weeks in the ischemic hind limb. Selectively targeting mTOR complex-1 (mTORC1) using low-dose rapamycin treatment with mADSCs attenuated proinflammatory cytokines (interleukin [IL]-1β and tumor necrosis factor-alpha [TNF-α]) expression and neutrophil/macrophage infiltration, which overtly promoted mADSCs viability and antiapoptotic/proangiogenic efficacy in vivo. However, targeting dual mTORC1/mTORC2 using PP242 or high-dose rapamycin caused IL-1β/TNF-α upregulation and anti-inflammatory IL-10, IL-6, and vascular endothelial growth factor/vascular endothelial growth factor receptor 2 downregulation, undermining the survival and antiapoptotic/proangiogenic action of mADSCs in vivo. Furthermore, low-dose rapamycin abrogated TNF-α secretion by mADSCs and rescued the cells from hypoxia/reoxygenation-induced death in vitro, while PP242 or high-dose rapamycin exerted proinflammatory effects and promoted cell death. In conclusion, mTORC1 and mTORC2 may differentially regulate inflammation and affect transplanted mADSCs' functional survival in ischemic hind limb. These findings uncover that mTOR may evolve into a promising candidate for mechanism-driven approaches to facilitate the translation of cell-based PAD therapy.
Cognitive engineering
Authors: Wilson Kyle M. , Helton William S. , Wiggins Mark W.
Published: October 2012

Cognitive engineering is the application of cognitive psychology and related disciplines to the design and operation of human–machine systems. Cognitive engineering combines both detailed and close study of the human worker in the actual work context and the study of the worker in more controlled environments. Cognitive engineering combines multiple methods and perspectives to achieve the goal of improved system performance. Given the origins of experimental psychology itself in issues regarding the design of human–machine systems, cognitive engineering is a core, or fundamental, discipline within academic psychology. WIREs Cogn Sci 2013, 4:17–31. doi: 10.1002/wcs.1204

This article is categorized under:

Psychology > Reasoning and Decision Making