bluuebunny/crossref_metadata_2025 huggingface dataset:
Downregulation of MED23 promoted the tumorigenecity of esophageal squamous cell carcinoma
Authors: Shi Jianxin , Han Qingqi , Zhao Heng , Zhong Chenxi , Yao Feng
Published: April 2013

Esophageal squamous cell carcinoma (ESCC) is one of the most common tumors in the world. It is very urgent to develop new therapeutic strategies. MED23, a component of the mediator complex, is known as a hub to integrate various signaling pathways. However, the function of MED23 in ESCC remains unknown. Here, we found that the expression of MED23 was downregulated in the clinical ESCC samples and the expression of MED23 reversely correlated with tumor size and clinical stage. Moreover, overexpression of MED23 in ESCC cells inhibited cell growth dramatically, while downregulation of MED23 promoted the tumorigenecity of ESCC cells in vitro and in vivo. Mechanistically, knockdown the expression of MED23 inhibited cell apoptosis by downregulation of Bax, activated Caspase 3, activated Caspase 9 and upregulation of cyclinD1 and Bcl2. Taken together, our study revealed the suppressive role of MED23 in ESCC and MED23 might be an important therapeutic target in ESCC. © 2013 Wiley Periodicals, Inc.
Indole‐3‐carbinol protects against pressure overload induced cardiac remodeling via activating AMPK‐α
Authors: Deng Wei , Zong Jing , Bian Zhouyan , Zhou Heng , Yuan Yuan , Zhang Rui , Guo Haipeng , Zhang Yan , Shen Difei , Li Hongliang , Tang Qizhu
Published: April 2013

Scope

Indole‐3‐carbinol (I3C), a monomer component extracted from leaves and stems of cruciferous vegetables, has inhibitory effects on tumors, obesity, and liver fibrosis, but its effects on the development of cardiac remodeling remain completely unknown. We determined the effects of I3C on cardiac remodeling and heart function using an aortic banding (AB) mouse model.

Methods and results

Male 8‐ to10‐wk‐old wild‐type and 5′ adenosine monophosphate‐activated protein kinase (AMPK)‐α2 knockout mice fed with or without I3C were subjected to AB or a sham operation and were phenotyped, accordingly. I3C both prevented and reversed cardiac remodeling induced by AB, as assessed by heart weight/body weight, lung weight/body weight, and heart weight/tibia length ratios, echocardiographic and hemodynamic parameters, histological analysis, and gene expression of hypertrophic and fibrotic markers. The inhibitory effect of I3C on cardiac remodeling was mediated by AMPK‐α and extracellular signal‐regulated kinases 1/2 (ERK1/2) signaling. Moreover, AMPK‐α2 gene deficiency completely blocked the inhibitory effects of I3C on cardiac remodeling, preventing the improvements in heart weight/body weight, lung weight/body weight, heart weight/tibia length, cardiac function, gene expression of hypertrophic and fibrotic markers, and phosphorylation of mammalian target of rapamycin and ERK1/2 signaling components.

Conclusion

I3C both prevents and reverses cardiac remodeling by activating AMPK‐α signaling. I3C is a potential therapeutic drug for heart failure.
Epicatechin regulation of mitochondrial structure and function is opioid receptor dependent
Authors: Panneerselvam Mathivadhani , Ali Sameh S. , Finley J. Cameron , Kellerhals Sarah E. , Migita Michael Y. , Head Brian P. , Patel Piyush M. , Roth David M. , Patel Hemal H.
Published: April 2013

Scope

The flavanol (–)‐epicatechin (Epi), a component of cacao, has cardiac protective benefits in humans. Our previous study demonstrated Epi has δ‐opioid receptor (DOR) binding activity and promotes cardiac protection. Here we examined the effects of 10 days of Epi treatment on: cardiac mitochondrial respiration, reactive oxygen species production, calcium swelling, and mitochondrial membrane fluidity.

Methods and results

Mice were randomized into four groups: (i) control (saline), (ii) naltrindole (Nalt; DOR antagonist), (iii) Epi, and (iv) Epi + Nalt and received 1 mg/kg Epi or water via oral gavage. Nalt groups received 5 mg/kg ip per day for 10 days. Significant increases in mitochondrial respiration and enhanced free radical production during state 3 respiration were observed with Epi. Additionally, we observed significant increases in rigidity of mitochondrial membranes and resistance to calcium‐induced mitochondrial swelling with Epi treatment. Blocking the DOR with Nalt resulted in decreases in all of the observed parameters by Epi treatment.

Conclusion

These findings indicate that Epi induces an integrated response that includes metabolic and structural changes in cardiac mitochondria resulting in greater functional capacity via DOR. Mitochondrial targeted effects of epicatechin may explain the physiologic benefit observed on cardiac protection and support epicatechin's potential clinical application as a cardiac protective mimetic.
Bioavailability of the major bioactive diterpenoids in a rosemary extract: Metabolic profile in the intestine, liver, plasma, and brain of Zucker rats
Authors: Romo Vaquero María , García Villalba Rocío , Larrosa Mar , Yáñez‐Gascón María J. , Fromentin Emilie , Flanagan John , Roller Marc , Tomás‐Barberán Francisco A. , Espín Juan C. , García‐Conesa María‐Teresa
Published: April 2013

Scope

Carnosic acid (CA) and derived diterpenes abundant in rosemary extracts (REs) exert anti‐obesity effects. The aim of this study was to investigate the bioavailability of these compounds in a rat model of obesity.

Methods and results

A total of 26 compounds were tentatively identified based on accurate mass information and the isotopic pattern provided by TOF‐MS analyzer. The main metabolites detected in the gut content, liver, and plasma were the glucuronide conjugates of CA, carnosol, and rosmanol. Two other metabolites were also identified: CA 12‐methyl ether and 5,6,7,10‐tetrahydro‐7‐hydroxyrosmariquinone. All the metabolites were detected as early as 25 min following oral administration. Most of the compounds remained in the intestine, liver, and (or) plasma at substantial concentrations for several hours supporting their potential health benefits in these tissues. We also corroborated the presence of small quantities of CA and detected trace quantities of the main CA metabolites in the brain. Notably, we did not find significant differences in the metabolic profile between lean and obese rats.

Conclusion

We report for the first time a comprehensive profile of metabolites in various organs following the oral consumption of an RE enriched in CA and contribute to establish the potential bioactive molecules.
A homogenization approach for evaluating the longitudinal shear stiffness of reinforced soils: column versus cross trench configuration
Authors: Gueguin Maxime , de Buhan Patrick , Hassen Ghazi
Published: April 2013

The macroscopic linear elastic behaviour of inclusion‐reinforced soils, regarded as periodic composite media, is investigated by means of the homogenization theory. Special attention is given here to the determination of their longitudinal shear stiffness properties, which strongly govern the reinforced ground response under lateral loading. Combining the use of analytical, variational and numerical methods, we thoroughly examined three particular engineering‐relevant configurations: single trench, column and cross trench reinforcements. Fairly accurate closed‐form expressions are thus obtained, giving the value of the reinforced soil longitudinal shear stiffness as a function of the individual components shear moduli and reinforcement volume fraction. It is shown in particular that adopting a cross trench reinforcement layout instead of the classical column configuration results in a much higher improvement of the longitudinal shear stiffness. The results are then applied to assessing the reduction of soil liquefaction risk, which can be attributed to the presence of the reinforcing inclusions. Again, they clearly demonstrate the excellent performance of the cross trench configuration as compared with the complete inefficiency of the column reinforcement technique. Copyright © 2013 John Wiley & Sons, Ltd.
Lateral strength and critical depth in infinite slope stability analysis
Authors: Doglioni A. , Galeandro A. , Simeone V.
Published: April 2013

Infinite slope (IS) method is the simplest limit equilibrium method for slope stability analysis. It gives reliable results for slides where the longitudinal dimension prevails on the depth of the landslide. Usually results are conservative since ignoring the effects of the strength along lateral bounds. Here, starting from the assumption of considering the effects of the shear strength along lateral bounds by a rectangular cross section, a new expression of the safety factor is investigated, based first on an elliptical and then on a parabolic cross section of the landslide mass. The safety factor evaluated in this way can be quite different from those returned by the classic formula of IS model, in particular when the width of the landslide is narrow with respect to its depth and the ratio between the width and the depth of the landslide is lower than 5. An interesting implication of the proposed model is that if cohesion differs from zero, there is a ‘critical depth’, where the safety factor has a minimum value. Copyright © 2013 John Wiley & Sons, Ltd.
A new numerical method of considering local longitudinal dispersion in single fractures
Authors: Zhao Zhihong , Jing Lanru , Neretnieks Ivars , Moreno Luis
Published: April 2013

The solutions of advection–dispersion equation in single fractures were carefully reviewed, and their relationships were addressed. The classic solution, which represents the resident or flux concentration within the semi‐infinite fractures under constant concentration or flux boundary conditions, respectively, describes the effluent concentration for a finite fracture. In addition, it also predicts the cumulative distribution of solute particle residence time passing through a single fracture under pulse injection condition, based on which a particle tracking approach was developed to simulate the local advection–dispersion in single fractures. We applied the proposed method to investigate the influence of local dispersion in single fractures on the macrodispersion in different fracture systems with relatively high fracture density. The results show that the effects of local dispersion on macrodispersion are dependent on the heterogeneity of fracture system, but generally the local dispersion plays limited roles on marodispersion at least in dense fracture network. This trend was in agreement with the macrodispersion in heterogeneous porous media. Copyright © 2013 John Wiley & Sons, Ltd.
Mucosal biomarkers of colorectal cancer risk do not increase at 6 months following sleeve gastrectomy, unlike gastric bypass
Authors: Kant Prashant , Perry Sarah L. , Dexter Simon P. , Race Amanda D. , Loadman Paul M. , Hull Mark A.
Published: April 2013

Objective

The hypothesis that sleeve gastrectomy (SG) is not associated with an increase in mucosal colorectal cancer (CRC) biomarkers, unlike Roux‐en‐Y gastric bypass (RYGB), was tested.

Design and Methods

Rectal mucosa, blood, and urine were obtained from morbidly obese patients (n = 23) before and after (median 28 months) SG, as well as from nonobese controls (n = 20). Rectal epithelial cell mitosis and apoptosis, crypt size/fission, and pro‐inflammatory gene expression were measured, as well as systemic inflammatory biomarkers, including C‐reactive protein (CRP).

Results

The mean pre‐operative body mass index in SG patients was 65.7 kg/m2 (24.7 kg/m2 in controls). Mean excess weight loss post‐SG was 38.2%. There was a significant increase in mitosis frequency, crypt size, and crypt fission (all P < 0.01) in SG patients versus controls, as well as evidence of a chronic inflammatory state (raised CRP and mononuclear cell p65 NFκB binding), but there was no significant change in these biomarkers after SG, except CRP reduction. Macrophage migration inhibitory factor mRNA levels were increased by 39% post‐SG (P = 0.038).

Conclusions

Mucosal biomarkers of CRC risk do not increase at 6 months following SG, unlike RYGB. Biomarkers of rectal crypt proliferation and systemic inflammation are increased in morbidly obese patients compared with controls.
Improved memory function two years after bariatric surgery
Authors: Alosco Michael L. , Spitznagel Mary Beth , Strain Gladys , Devlin Michael , Cohen Ronald , Paul Robert , Crosby Ross D. , Mitchell James E. , Gunstad John
Published: April 2013

Objective

Obesity is as an independent risk factor for poor neurocognitive outcomes, including Alzheimer's disease. Bariatric surgery has recently been shown to result in improved memory at 12‐weeks postoperatively. However, the long‐term effects of bariatric surgery on cognitive function remain unclear.

Design and Methods

Eighty‐six individuals (63 bariatric surgery patients, 23 obese controls) were recruited from a prospective study examining the neurocognitive effects of bariatric surgery. All participants completed self‐report measurements and a computerized cognitive test battery prior to surgery and at 12‐week and 24‐month follow‐up; obese controls completed measures at equivalent time points.

Results

Bariatric surgery patients exhibited high rates of pre‐operative cognitive impairments in attention, executive function, memory, and language. Relative to obese controls, repeated measures ANOVA showed improvements in memory from baseline to 12‐weeks and 24‐months postoperatively (P < 0.05). Regression analyses controlling for baseline factors revealed that a lower BMI at 24‐months demonstrated a trend toward significance for improved memory (β = −.30, P = 0.075).

Conclusion

These findings suggest that cognitive benefits of bariatric surgery may extend to 24‐months postoperatively. Larger prospective studies with extended follow‐up periods are needed to elucidate whether bariatric surgery decreases risk for cognitive decline and possibly the development of dementia.
Musculoskeletal deterioration in men accompanies increases in body fat
Authors: Pasco Julie A , Gould Haslinda , Brennan Sharon L , Nicholson Geoff C. , Kotowicz Mark A
Published: April 2013

Objective

To examine body fat and musculoskeletal changes in men over 5 years.

Methods

Body composition was evaluated for men in the Geelong Osteoporosis Study using whole body dual energy X‐ray absorptiometry (DXA) during two time‐periods. DXA was performed for 1329 men (25‐96 years) during 2001‐2006 and for 900 men (25‐98 years), 2006‐2011. The masses of fat, lean, and bone were expressed relative to the square of height (kg/m2). Each compartment was also expressed as a percentage relative to body weight (%fat, %lean, %bone).

Results

Mean BMI increased from 26.9 kg/m2 in 2001‐2006, to 27.2 kg/m2 in 2006‐2011 (P = 0.04). Mean fat mass increased by 9.0% from 6.98 kg/m2 (95%CI 6.84‐7.11) in 2001‐2006, to 7.60 kg/m2 (7.44‐7.77) in 2006‐2011 (P < 0.001); mean lean mass decreased by 0.9%, from 18.92 kg/m2 (18.83‐19.01) to 18.75 kg/m2 (18.64‐18.86) (P = 0.02), and mean bone mass decreased 1.6% from 1.041 kg/m2 (1.034‐1.047), to 1.024 kg/m2 (1.016‐1.032). Mean %fat increased from 23.4% to 25.2%, mean %lean decreased from 72.6% to 70.9% and mean %bone decreased from 4.0% to 3.9% (all P < 0.05).

Conclusions

An increase in BMI, which reflects a substantial increase in body fat mass and declines in both lean and bone mass was reported. This may have implications for future development of bone fragility, sarcopenia, and sarcopenic obesity.
Routine testing of fetal Rhesus D status in Rhesus D negative women using cell‐free fetal DNA: an investigation into the preferences and information needs of women
Authors: Oxenford Kerry , Silcock Caroline , Hill Melissa , Chitty Lyn
Published: April 2013

Objective

The goal of this study is to investigate women's preferences and information needs for routine implementation of fetal Rhesus D (RhD) typing using cell‐free fetal DNA.

Methods

A questionnaire was developed following focus groups and interviews with both health professionals and RhD negative (RhD−) women offered fetal RhD genotyping within a research study and distributed to RhD− women attending routine antenatal appointments in four National Health Service hospitals. Current knowledge of blood types, anti‐D administration, fetal RhD genotyping and future practices were explored.

Results

A total of 19 respondents participated in interviews and focus groups, and 270 respondents completed the questionnaires. Questionnaire respondents overwhelmingly felt that the test should be offered to all RhD− women (92.1%), and 75.9% said that they would accept this test. Most were happy to have the test even if it involved extra blood tests (89.3%) or appointments (79%). The knowledge of blood groups was poor. Although 90.7% knew that the baby could have a different blood group from themselves, only 34% knew that blood groups are inherited from both parents. More than 40% were not aware that anti‐D would not be required if their baby was RhD−.

Conclusions

Women would welcome the introduction of routine fetal RhD genotyping. Information leaflets and training of midwives will be essential for implementation to ensure good understanding regarding testing. © 2013 The Authors. Prenatal Diagnosis published by John Wiley & Sons Ltd.
Experimental analysis of a photovoltaic concentrator based on a single reflective stage immersed in an optical fluid
Authors: Victoria Marta , Domínguez César , Askins Stephen , Antón Ignacio , Sala Gabriel
Published: April 2013

This article reviews all the experimental tests carried out to analyze the performance of a FluidReflex photovoltaic concentrator. This novel concentrator concept consists of a single reflective stage immersed in an optical fluid. The presence of the fluid entails significant advantages. It not only allows a high system optical efficiency and increases the attainable concentration but also enhances the heat dissipation from the cell. In addition, the electrical insulation is improved, and the problem of water vapor condensation inside the module is avoided. A complete characterization is addressed in this paper. Among the experimental results, a measured optical efficiency of 83.5% for a concentration of 1035× stands out. Copyright © 2013 John Wiley & Sons, Ltd.
UV nanoimprint for the replication of etched ZnO:Al textures applied in thin‐film silicon solar cells
Authors: Meier Matthias , Paetzold Ulrich W. , Prömpers Michael , Merdzhanova Tsvetelina , Carius Reinhard , Gordijn Aad
Published: April 2013

In this work, we present a technology for a high precision nanostructure replication process based on ultraviolet nanoimprint lithography for the application in the field of thin‐film photovoltaics. The potential of the technology is demonstrated by the fabrication of microcrystalline silicon thin‐film prototype solar cells. The high accuracy replication of random microstructures made from sputtered and etched ZnO:Al, used to scatter the incident light in thin solar cells, is shown by local topography investigations of the same 7.5 × 7.5 µm2 area on the master and the replica. Different types of imprint resists and imprint moulds were investigated to find the optimal, high precision replication technology. Two types of thin‐film silicon solar cells, in p‐i‐n and n‐i‐p configuration, were fabricated to study the potential of the imprint technology for different applications. It is shown that solar cells deposited on an imprinted glass hold similar performances compared with reference solar cells fabricated with a standard process on textured ZnO:Al. Thus, it is demonstrated that the replication of light scattering structures by using an imprint process is an attractive method to decouple the scattering properties from the layer forming the electrical front contact. Because a simple and cheap high throughput process is used, this study additionally proves the relevance for the industrial mass production in the field of photovoltaics. Copyright © 2013 John Wiley & Sons, Ltd.
The contribution of proteomics to the unveiling of the survival strategies used by Pseudomonas putida in changing and hostile environments
Authors: Moreno Renata , Rojo Fernando
Published: April 2013

Pseudomonas putida is a ubiquitous, metabolically very versatile, Gram‐negative bacterium adapted to habitats as diverse as soil, water and the rhizosphere. Most strains are nonpathogenic, many are used as experimental models, and many others have biotechnological applications in the areas of agriculture, bioremediation, biocatalysis, and the production of bioplastics. This review summarizes the contribution of proteomic technologies to our understanding of how P. putida responds to different carbon sources, how it adapts to living at suboptimal temperatures or attached to surfaces, and how it responds to the presence of toxic compounds such as aromatic molecules and heavy metals. The examples described illustrate the value of proteomics in furthering our knowledge of the physiology and behavior of bacteria, knowledge that is important for understanding how they behave in their natural habitats and for optimizing their behavior in biotechnological applications.
Dynamics of amino acid utilization in Phaeobacter inhibensDSM 17395
Authors: Zech Hajo , Hensler Michael , Koßmehl Sebastian , Drüppel Katharina , Wöhlbrand Lars , Trautwein Kathleen , Colby Thomas , Schmidt Jürgen , Reinhardt Richard , Schmidt‐Hohagen Kerstin , Schomburg Dietmar , Rabus Ralf
Published: April 2013

Time‐resolved utilization of multiple amino acids by Phaeobacter inhibens DSM 17395 was studied during growth with casamino acids. The 15 detected amino acids could be grouped according to depletion rate into four different categories, i.e. from rapid (category I) to nondepletion (category IV). Upon entry into stationary growth phase, amino acids of category I (e.g. glutamate) were (almost) completely depleted, while those of categories II (e.g. leucine) and III (e.g. serine) were further consumed at varying rates and to different extents. Thus, cultures entered stationary growth phase despite the ample presence of organic nutrients, i.e. under nonlimiting conditions. Integrated proteomic and metabolomic analysis identified 1747 proteins and 94 intracellular metabolites. Of these, 180 proteins and 86 metabolites displayed altered abundance levels during growth. Most strikingly, abundance and activity profiles of alanine dehydrogenase concomitantly increased with the onset of enhanced alanine utilization during transition into stationary growth phase. Most enzymes of amino acid and central metabolism, however, displayed unaltered abundances across exponential and stationary growth phases. In contrast, metabolites of the Entner–Doudoroff pathway and gluconeogenesis as well as cellular fatty acids increased markedly in abundance in early stationary growth phase.
Bioinformatic progress and applications in metaproteogenomics for bridging the gap between genomic sequences and metabolic functions in microbial communities
Authors: Seifert Jana , Herbst Florian‐Alexander , Halkjær Nielsen Per , Planes Francisco J. , Jehmlich Nico , Ferrer Manuel , von Bergen Martin
Published: April 2013

Metaproteomics of microbial communities promises to add functional information to the blueprint of genes derived from metagenomics. Right from its beginning, the achievements and developments in metaproteomics were closely interlinked with metagenomics. In addition, the evaluation, visualization, and interpretation of metaproteome data demanded for the developments in bioinformatics. This review will give an overview about recent strategies to use genomic data either from public databases or organismal specific genomes/metagenomes to increase the number of identified proteins obtained by mass spectrometric measurements. We will review different published metaproteogenomic approaches in respect to the used MS pipeline and to the used protein identification workflow. Furthermore, different approaches of data visualization and strategies for phylogenetic interpretation of metaproteome data are discussed as well as approaches for functional mapping of the results to the investigated biological systems. This information will in the end allow a comprehensive analysis of interactions and interdependencies within microbial communities.
Amphiphilic depsipeptide‐based block copolymers as nanocarriers for controlled release of ibuprofen with doxorubicin
Authors: Zhang Li , Feng Yakai , Tian Hong , Zhao Miao , Khan Musammir , Guo Jintang
Published: April 2013

Well‐defined amphiphilic multiblock copolymers PDMAEMA‐b‐P(IBMD‐co‐PDO)‐b‐PEG‐b‐P(IBMD‐co‐PDO)‐b‐PDMAEMA [PDMAEMA‐PIBMD‐PPDO‐PEG], based on poly(2‐(dimethylamino)ethyl methacrylate) block (PDMAEMA), poly(3(S)‐isobutyl‐morpholine‐2,5‐dione‐co‐p‐dioxanone) block (P(IBMD‐co‐PDO)), and poly(ethylene glycol) block (PEG) were successfully synthesized by combination of ring‐opening polymerization (using 3(S)‐isobutyl‐morpholine‐2,5‐dione and p‐dioxanone initiated by hydroxyl end of PEG) and atom transfer radical polymerization (ATRP). Furthermore, all these copolymers were characterized by 1H NMR, 13C NMR, Fourier transformed‐infrared, gel permeation chromatography, differential scanning calorimetry, and thermogravimetric analysis measurements. The degradation experiments showed that the molecular weight of PDMAEMA‐PIBMD‐PPDO‐PEG decreased along with degradation time. In addition, these copolymers could readily self‐assemble into nanosized microspheres in phosphate buffered solution. Ibuprofen (IBU) and doxorubicin (DOX) as a kind of combined model drugs were loaded into these microspheres by the combination of ionic interaction and hydrophobic effect. These copolymer microspheres exhibited high loading capacity (LC, up to 26.88%), encapsulation efficiency (EE, up to 61.29%), and sustained release behavior of IBU–DOX in phosphate buffered solution. The results of transmission electron microscopy and dynamic light scattering showed that the microspheres were well‐defined uniform spherical particles with average diameter less than 120 nm. Therefore, it can be envisaged that these copolymer systems are promising candidates for controlled release application. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3213–3226
From SEMP to SEMS to SEMS II
Authors: Sutton Ian
Published: April 2013

This article describes the new offshore safety management rule that is often referred to as SEMS II. © 2013 American Institute of Chemical Engineers Process Saf Prog 32: 311–312, 2013
Intercepted signals for ionospheric science
Authors: Lind F. D. , Erickson P. J. , Coster A. J. , Foster J. C. , Marchese J. R. , Berkowitz Z. , Sahr J. D.
Published: April 2013

The ISIS array (Intercepted Signals for Ionospheric Science) is a distributed, coherent software radio array designed for the study of geospace phenomena by observing the scatter of ambient radio frequency (RF) signals. ISIS data acquisition and analysis is performed using the MIDAS‐M platform (Millstone Data Acquisition System ‐ Mobile). Observations of RF signals can be performed between HF and L‐band using the Array nodes and appropriate antennas. The deployment of the Array focuses on observations of the plasmasphere boundary layer. We discuss the concept of the coherent software radio array, describe the ISIS hardware, and give examples of data from the system for selected applications. In particular, we include the first observations of E region irregularities using the Array. We also present single‐site passive radar observations of both meteor trails and E region irregularities using adaptive filtering techniques.
Improving the electrostatic field concentration in a negative‐permittivity wedge with a grounded “bowtie” configuration
Authors: Valagiannopoulos Constantinos A. , Sihvola Ari
Published: April 2013

Two wedges, one made of negative‐permittivity material (primary) and another of an ordinary dielectric (auxiliary/secondary), are posed nose‐to‐nose to form a “bowtie” configuration. This shape is very common and convenient for a number of real‐world devices and constructions such as electron microscopes, optical superlenses, and nanotips. In all these structures, the efficient operation and functionality get strongly assisted by the increased electromagnetic power concentration in the vicinity of the edge. Such a field enhancement is attempted with proper choice of the characteristics of the dielectric wedge to increase the field intensity over the cross section of the metamaterial one. A slowly varying field assumption is adopted to formulate approximate solutions to similar structures (sharp and rounded corners). A quality factor has been defined based on the power carried by the supported modal waves, if they are excited by a suitable electric source, in the presence and in the absence of the auxiliary wedge. This quantity expresses the intensity enhancement that could be achieved and is represented in graphs with respect to the dielectric wedge parameters. The characteristics of the secondary component that lead to a maximization of the electric power into the primary one are identified and explained. In particular, periodic variations of the angular extent of the secondary wedge are observed, and the number of maxima is increased with the dielectric permittivity of the constituent material.
Spatio‐temporal interpolation of total electron content using a GPS network
Authors: Deviren M. N. , Arikan F. , Arikan O.
Published: April 2013

Constant monitoring and prediction of Space Weather events require investigation of the variability of total electron content (TEC), which is an observable feature of ionosphere using dual‐frequency GPS receivers. Due to various physical and/or technical obstructions, the recordings of GPS receivers may be disrupted resulting in data loss in TEC estimates. Data recovery is very important for both filling in the data gaps for constant monitoring of ionosphere and also for spatial and/or temporal prediction of TEC. Spatial prediction can be obtained using the neighboring stations in a network of a dense grid. Temporal prediction recovers data using previous days of the GPS station in a less dense grid. In this study, two novel and robust spatio‐temporal interpolation algorithms are introduced to recover TEC through optimization by using least squares fit to available data. The two algorithms are applied to a regional GPS network, and for a typical station, the number of days with full data increased from 68% to 85%.
Configuring effective navigation models and abstract test cases for web applications by analysing user behaviour
Authors: Sprenkle Sara E. , Pollock Lori L. , Simko Lucy M.
Published: April 2013

As web applications become more complex and are used more pervasively, testing demands are increasing without corresponding automated support. One promising approach to automatic test generation is statistical model‐based testing, where logged user behaviour is used to build a usage‐based model of web application navigation, from which abstract test cases are generated. Executable test cases are then created by adding parameter values to the abstract test cases. Several researchers have proposed variations of this approach; however, no one has empirically examined the tradeoffs and implications of the different ways to represent user behaviour in a navigation model and the characteristics of the test cases automatically generated from different models. This paper reports on our exploratory study of automatically generated abstract test cases and the underlying usage‐based navigation models constructed from over 19,000 user sessions across five publicly deployed web applications. Our results suggest how web testers can easily configure statistical model‐based automatic test case generators for web applications toward generating tests closely related to user behaviour or toward new navigations without using large additional test resources. Copyright © 2013 John Wiley & Sons, Ltd.
The deep space galactic cosmic ray lineal energy spectrum at solar minimum
Authors: Case A. W. , Kasper J. C. , Spence H. E. , Zeitlin C. J. , Looper M. D. , Golightly M. J. , Schwadron N. A. , Townsend L. W. , Mazur J. E. , Blake J. B. , Iwata Y.
Published: April 2013

The Cosmic Ray Telescope for the Effects of Radiation (CRaTER) instrument is an energetic particle telescope on board the Lunar Reconnaissance Orbiter spacecraft. CRaTER measures energetic charged particles that have sufficient energy to penetrate the outer shielding of the instrument (about 12 MeV/nucleon). Galactic cosmic rays (GCR) with these energies are the primary radiation concern for spacecraft and astronauts outside of the Earth's magnetosphere during times of minimal solar activity. These particles can easily penetrate typical shielding and damage electronics, causing increased electronics failure rates and single event upsets. When this radiation impacts biological cells, it causes an increased risk of cancer. The CRaTER instrument was built to characterize the radiation dose and lineal energy with unprecedented time and energy resolution and was fortuitously flown during a period of time that coincided with the highest GCR fluxes in the modern space age. We report here this worst‐case GCR lineal energy spectrum. Observations are made behind a thin aluminum window and different thicknesses of tissue‐equivalent plastic. These measurements provide important observational data points to compare with current model predictions of the dose deposited by energetic particles within a tissue‐like material.
Situated embodied cognition: Monitoring orientation cues affects product evaluation and choice
Authors: Eelen Jiska , Dewitte Siegfried , Warlop Luk
Published: April 2013

Consumers generally prefer products that are easy to interact with. In three studies, we show that this preference arises from the fit between product orientation and monitored situational constraints. Flexible right‐handers, who monitor situational constraints, recall product orientations better and prefer products for which the handle is oriented in the direction of the hand used for grasping. When their ability to monitor situational constraints is impaired, the preference for easy‐to‐grasp products is attenuated. The findings highlight that motor fluency is a relevant cue for decision making when consumers assess how to interact with a product. The implications of these results for embodiment and fluency research are discussed.
Flame front/turbulence interaction for syngas fuels in the thin reaction zones regime: turbulent and stretched laminar flame speeds at elevated pressures and temperatures
Authors: Daniele S. , Mantzaras J. , Jansohn P. , Denisov A. , Boulouchos K.
Published: April 2013

Experiments were performed in dump-stabilized axisymmetric flames to assess turbulent flame speeds (${S}_{T} $) and mean flamelets speeds (stretched laminar flame speeds, ${S}_{L, k} $). Fuels with significantly different thermodiffusive properties have been investigated, ranging from pure methane to syngas (${\mathrm{H} }_{2} \text{{\ndash}} \mathrm{CO} $ blends) and pure hydrogen, while the pressure was varied from 0.1 to 1.25 MPa. Flame front corrugation was measured with planar laser-induced fluorescence (PLIF) of the OH radical, while turbulence quantities were determined with particle image velocimetry (PIV). Two different analyses based on mass balance were performed on the acquired flame images. The first method assessed absolute values of turbulent flame speeds and the second method, by means of an improved fractal methodology, provided normalized turbulent flame speeds (${S}_{T} / {S}_{L, k} $). Deduced average Markstein numbers exhibited a strong dependence on pressure and hydrogen content of the reactive mixture. It was shown that preferential-diffusive-thermal (PDT) effects acted primarily on enhancing the stretched laminar flame speeds rather than on increasing the flame front corrugations. Interaction between flame front and turbulent eddies measured by the fractal dimension was shown to correlate with the eddy temporal activity.
Shear-induced diffusion of red blood cells in a semi-dilute suspension
Authors: Omori T. , Ishikawa T. , Imai Y. , Yamaguchi T.
Published: April 2013

The diffusion of red blood cells (RBCs) in blood is important to the physiology and pathology of the cardiovascular system. In this study, we investigate flow-induced diffusion of RBCs in a semi-dilute system by calculating the pairwise interactions between RBCs in simple shear flow. A capsule with a hyperelastic membrane was used to model an RBC. Its deformation was resolved using the finite element method, whereas fluid motion inside and outside the RBC was solved using the boundary element method. The results show that shear-induced RBC diffusion is significantly anisotropic, i.e. the velocity gradient direction component is larger than the vorticity direction. We also found that the motion of RBCs during the interaction is strongly dependent on the viscosity ratio of the internal to external fluid, and the diffusivity decreases monotonically as the viscosity ratio increases. The scaling argument also suggests that the diffusivity is proportional to the shear rate and haematocrit, if the suspension is in a semi-dilute environment and the capillary number is invariant. These fundamental findings are useful to understand transport phenomena in blood flow.
Unravelling the basis of variability in cobalamin levels in the general population
Authors: Andrew Toby , Gill Raj , Gillham-Nasenya Irina , Ahmadi Kourosh R.
Published: April 2013

Cobalamin (Cbl) is an essential B vitamin involved in the normal functioning of the nervous system, the formation of key components of blood, DNA synthesis and methylation, and energy production. Physiological levels of Cbl vary greatly within populations, although the basis for this variability remains largely unknown. We conducted a twin study to characterise the basis of variation in plasma Cbl levels and to test whether common genetic polymorphisms in genes known to cause defects in inborn errors of Cbl metabolism and transport are also associated with mean plasma Cbl levels in the general population. The present results showed that plasma levels of Cbl were heritable, with genetic and phenotypic variance increasing with age, and levels significantly correlated with age, BMI, exercise, alcohol consumption, smoking status, social class and folate levels, which collectively accounted for up to 15 % of Cbl variation. Of eight genes responsible for the defects of the Cbl metabolic pathway (cblA–G and mut), MMAA, MMACHC, MTRR and MUT harboured polymorphisms that showed evidence of association with Cbl levels. Characterisation of the heritable component of variation in Cbl levels can facilitate the early diagnosis and prognosis of Cbl insufficiency/deficiency in individuals at a higher risk of associated diseases.
“Royal Pierrots” and “White Coons”: the British Pierrot Troupe in the Racial and National Imaginary
Authors: Calvert Dave
Published: April 2013

The Pierrot tradition, invented towards the end of the nineteenth century, established a prevalent but now largely forgotten mode of performance around the coastal resorts of Britain. In this article, Dave Calvert considers the relevance of this form in its historical context. Arguing that it observes the preservation of anachronism consistent with notions of invented traditions, he situates the Pierrot tradition within a symbolic network concerned with national identity and experience. This includes its declared links to the construction of royalty as the head of the imperial family, and both its schism and continuity with the tradition of blackface minstrelsy whose conventions it maintains. Its location at the seaside accentuates this network of relations and elevates it to a transcendental plane of the imaginary untroubled by the complexities of modern life. Dave Calvert is a Senior Lecturer in Drama at the University of Huddersfield. His research encompasses popular theatre, applied theatre and learning-disabled performance. He is also a member of The Pierrotters, the last remaining professional seaside Pierrot troupe.
Guilt, Nostalgia, and Victimhood: Korea in the Japanese Theatrical Imagination
Authors: Sorgenfrei Carol Fisher
Published: April 2013

How has post-war Japanese theatre grappled with Japanese responsibility for its imperialistic/militaristic past in Asia, and for institutionalized discrimination against resident minorities? Using the tools of guilt, nostalgia, and the valorization of victimhood that are embedded in the idea of hōgan biiki (sympathy for the loser/victims), Carol Fisher Sorgenfrei here analyzes Japan's often contradictory, flip-flopping self-image as both victimizer and victim in relation to Korea and resident Koreans. Looking at both mainstream and alternative performances, her article suggests that despite attempts to discuss these issues openly, most theatre artists actually present images that soften or displace responsibility for the past. Carol Fisher Sorgenfrei is Professor Emerita of Theatre at UCLA, and was recently a Research Fellow at the Institute for Interweaving Performance Cultures, Freie Universität, Berlin. An authority on post-war Japanese and cross-cultural performance, she is also a translator, director, and award-winning playwright. Her books include Unspeakable Acts: the Avant-Garde Theatre of Terayama Shuji and Postwar Japan and the co-authored Theatre Histories: an Introduction. She has published numerous articles and presented papers and keynotes throughout the world. Professor Sorgenfrei is Associate Editor of Asian Theatre Journal and Editor of the Association for Asian Performance Newsletter.
THE DECLINE OF THE GERMAN MANDARINS
Authors: WOLIN RICHARD
Published: April 2013

The term “intellectual” is a French coinage that dates to the years preceding the Dreyfus affair. Nevertheless, the concept has a distinguished pedigree that can be traced back to Voltaire's heroic interventions under the ancien régime—most notably, the Calas affair—as well as Victor Hugo's vehement protests against Louis Bonaparte's petty caesarism. The first intellectuals were, as a rule, littérateurs. They were interlopers who relied on the renown they had accrued in their field of expertise to hazard moral pronouncements about actualités or current events. By virtue of their literary or scientific prestige—or, to use a contemporary locution, their “cultural capital”—they hoped to shame the political authorities into rectifying a gross miscarriage of justice. As Jean-Paul Sartre once put it, intellectuals are “those who involve themselves in matters that are none of their business.”
Bluttransfusionen: Risiken jenseits von übertragbaren
Krankheiten
Authors: Horn C. , Büser N. , von Freyburg A. , Scherer M.
Published: April 2013

Bluttransfusionen gehören in der Orthopädie und Unfallchirurgie nach wie vor
zum klinischen Alltag. Durch geänderte Transfusionsrichtlinien, neue
OP-Techniken und einem besseren Verständnis der anämiebedingten
Pathophysiologie kann die Indikation zur Transfusion zunehmend strenger
gestellt werden. Dies ist umso wichtiger, als sich in den letzten Jahren
Hinweise mehren, dass Bluttransfusionen einen nicht unerheblichen Einfluss
auf die Krankenhausmortalität und das Outcome des Patienten haben. Dieser
Artikel soll einen Überblick über die Literatur der letzten Jahre liefern,
die sich mit dieser Problematik beschäftigen.
Analysis of plasma-magnetic photonic crystal with a tunable band gap
Authors: Mehdian H. , Mohammadzahery Z. , Hasanbeigi A.
Published: April 2013

In this paper, electromagnetic wave propagation through the one-dimensional plasma-magnetic photonic crystal in the presence of external magnetic field has been analyzed. The dispersion relation, transmission and reflection coefficients have been obtained by using the transfer matrix method. It is investigated how photonic band gap of photonic crystals will be tuned when both dielectric function ε and magnetic permeability μ of the constitutive materials, depend on applied magnetic field. This is shown by one dimensional photonic crystals consisting of plasma and ferrite material layers stacked alternately.
Gradient instabilities of electromagnetic waves in Hall thruster plasma
Authors: Tomilin Dmitry
Published: April 2013

This paper presents a linear analysis of gradient plasma instabilities in Hall thrusters. The study obtains and analyzes the dispersion equation of high-frequency electromagnetic waves based on the two-fluid model of a cold plasma. The regions of parameters corresponding to unstable high frequency modes are determined and the dependence of the increments and intrinsic frequencies on plasma parameters is obtained. The obtained results agree with those of previously published studies.
Kinetic water-bag model of global collisional drift waves and ion temperature gradient instabilities in cylindrical geometry
Authors: Gravier E. , Plaut E.
Published: April 2013

Collisional drift waves and ion temperature gradient (ITG) instabilities are studied using a linear water-bag kinetic model [P. Morel et al., Phys. Plasmas 14, 112109 (2007)]. An efficient spectral method, already validated in the case of drift waves instabilities [E. Gravier et al., Eur. Phys. J. D 67, 7 (2013)], allows a fast solving of the global linear problem in cylindrical geometry. The comparison between the linear ITG instability properties thus computed and the ones given by the COLUMBIA experiment [R. G. Greaves et al., Plasma Phys. Controlled Fusion 34, 1253 (1992)] shows a qualitative agreement. Moreover, the transition between collisional drift waves and ITG instabilities is studied theoretically as a function of the ion temperature profile.
Nonplanar waves with electronegative dusty plasma
Authors: Zobaer M. S. , Mukta K. N. , Nahar L. , Roy N. , Mamun A. A.
Published: April 2013

A rigorous theoretical investigation has been made of basic characteristics of the nonplanar dust-ion-acoustic shock and solitary waves in electronegative dusty plasma containing Boltzmann electrons, Boltzmann negative ions, inertial positive ions, and charge fluctuating (negatively charged) stationary dust. The Burgers' and Korteweg–de Vries (K-dV) equations, which is derived by reductive perturbation technique, is numerically solved to examine the effects of nonplanar geometry on the basic features of the DIA shock and solitary waves formed in the electronegative dusty plasma. The implications of the results (obtained from this investigation) in space and laboratory experiments are briefly discussed.
A model distribution function for relativistic bi-Maxwellian with drift
Authors: Naito O.
Published: April 2013

A model distribution function for relativistic bi-Maxwellian with drift is proposed, based on the maximum entropy principle and the relativistic canonical transformation. Since the obtained expression is compatible with the existing distribution functions and has a relatively simple form as well as smoothness, it might serve as a useful tool in the research fields of space or high temperature fusion plasmas.
The constitutive tensor of linear elasticity: Its decompositions, Cauchy relations, null Lagrangians, and wave propagation
Authors: Itin Yakov , Hehl Friedrich W.
Published: April 2013

In linear anisotropic elasticity, the elastic properties of a medium are described by the fourth rank elasticity tensor C. The decomposition of C into a partially symmetric tensor M and a partially antisymmetric tensors N is often used in the literature. An alternative, less well-known decomposition, into the completely symmetric part S of C plus the reminder A, turns out to be irreducible under the three-dimensional general linear group. We show that the SA-decomposition is unique, irreducible, and preserves the symmetries of the elasticity tensor. The MN-decomposition fails to have these desirable properties and is such inferior from a physical point of view. Various applications of the SA-decomposition are discussed: the Cauchy relations (vanishing of A), the non-existence of elastic null Lagrangians, the decomposition of the elastic energy and of the acoustic wave propagation. The acoustic or Christoffel tensor is split in a Cauchy and a non-Cauchy part. The Cauchy part governs the longitudinal wave propagation. We provide explicit examples of the effectiveness of the SA-decomposition. A complete class of anisotropic media is proposed that allows pure polarizations in arbitrary directions, similarly as in an isotropic medium.