bluuebunny/crossref_metadata_2025 huggingface dataset:
Spacecraft Structures: Development
Authors: Marulo Francesco
Published: July 2012

Current spacecraft designs include materials and structural systems engineered to satisfy a variety of requirements, including structural integrity, damage tolerance, radiation protection, debris/micrometeoroid shielding, and thermal insulation. To comply with these different design requirements, composite materials are tailored and designed for specific application and constraint. A survey of the present status of composite materials technology is made with emphasis on materials and applications useful in spacecraft structures. Information is obtained from the open literature, by attendance at meetings and symposia, and from the World Wide Web.

Brief discussions of the theory of composite strengthening and reinforcement mechanics are included. Advantages, disadvantages, problem areas, and actual and potential applications are described. The status of testing, processing, forming, fabrication, and joining are noted, and the opportunities offered by employing composite materials for spacecraft applications are described. The advantages as well as the drawbacks behind the use of composites are also listed with specific reference to the space environment. The most critical aspects, which involve the design and the development of a spacecraft are presented with reference to composite materials specifications and guidelines for selection. Next, the characteristics of fiber‐reinforced composite materials are listed. It is shown that composites possess significant advantages over presently used spacecraft structural materials; these include superior strength‐to‐weight and stiffness‐to‐weight ratios, more design freedom and flexibility, improved resistance to crack propagation, and greater potential for improvement of properties. Major problems include lack of uniform test methods, difficulty of joining, high cost, difficulty of fabrication and processing, and lack of information on reliability and reproducibility, particularly for the more advanced composites.
Stainless Steel Polymer Composites
Authors: Akhtar Farid
Published: July 2012

In electronic, automotive, medical, and aerospace industries, electrostatic discharge (ESD) control and electromagnetic interference (EMI) shielding are important design considerations. Conductive polymer composites are well researched and commercially available materials for ESD control and EMI shielding. Several kinds of conductive fillers are incorporated in the form of particulates and fibers in polymer matrix. A comparison between various conductive fillers in polymer matrix is presented. Stainless steel fibers as conductive filler for polymer matrix offer several advantages. Polymer composites show resistivities in the range of 10
3
−10
6
 Ω/sq at a volume fraction as low as 0.75 vol% of stainless steel fibers. The effect of filler size, shape of the filler, critical volume fraction, and effect of polymer matrix on the ESD control/EMI shielding properties of the stainless steel‐reinforced conductive polymer composite is discussed. Important parameters are described to obtain effective ESD control and EMI shielding using stainless fiber polymer matrix composites. Several reported stainless steel‐reinforced polymer composites are summarized and their effectiveness for ESD control and EMI shielding is compared.
Standards for Composite Materials: National, European, and International
Authors: Sims Graham D.
Published: July 2012

The advanced polymer matrix composites (PMCs) industry is an international business, with suppliers, producers, and users all operating globally. Hence, there is a great demand for international standards and specifications to further the use of advanced PMCs and the growth of the industry. In 2010, the many international standards describing test methods for the lower performance PMCs that have discontinuous mat, or fabric reinforcements, have been joined by equivalent methods for the “advanced” continuous fiber‐reinforced systems. This article reviews the development and validation of new standard test methods and documents the current initiatives related to the advanced PMC materials. In particular, the standards and methods being developed by the International Standards Organization (ISO) by the Comitée Européen de Normalisation (CEN) in support of the Single (European) Market and American Society for Testing and Materials (ASTM) are highlighted. These test methods underpin the standards for composite products and intermediate products that are increasingly, being developed, although product standards (e.g., lighting columns, gas cylinders, piping, pultrusions) are not currently covered in this article.
Statistical Fracture Theories
Authors: Zapperi Stefano , Nukala Phani K. V. V. , Alava Mikko J.
Published: July 2012

In this article, we review theories and models used to account for size effects in the fracture of disordered media. We discuss extreme value statistics, fiber bundle models (FBMs), and network models of fracture. We briefly discuss the application of these concepts to the failure of composites.
Structural Composite Design: Concepts and Considerations
Authors: Bruyneel Michael , Diaconu Cezar
Published: July 2012

In this article, the structural composite design process is presented. It is shown that it is an extremely complicated task conducted nowadays with computers and numerical tools. It involves several disciplines, including computer‐aided design (CAD), computer‐aided engineering (CAE), and computer‐aided manufacturing (CAM), in an iterative process where optimization plays a very important role. The CAE of composite structures is described, and several ways to parameterize the laminates are explained. These parameterizations form the basis for the introduction of formulations for the structural composite optimal design, which is the main topic addressed here. Several optimization approaches have been proposed over the past years, but a global solution is not yet available. The ultimate solution procedure should address the problem at the CAD‐CAE‐CAM levels simultaneously, in order to provide light and safe designs that are ready to manufacture. Since the aeronautics industry has driven the innovation in structural composite design, most of the concepts described here are based on the developments carried out for large composite aircrafts.
Structure and Fracture Mechanics of Injection‐Molded Composites
Authors: Karger‐Kocsis József
Published: July 2012

This article gives an overlook on the microstructural development and microstructure‐related fracture and fatigue behaviors of short and long discontinuous fiber‐reinforced injection‐molded composites. The fracture and fatigue crack propagation of the related composites were assessed by fracture mechanical concepts and interpreted as a function of molding‐induced microstructure. The failure caused by different test conditions was analyzed by fractography and discussed. Recommendations were given on how to design injection‐molded thermoplastic matrix composite parts by using the fracture mechanical data.
Superconducting Composites
Authors: Romanovskii Vladimir R.
Published: July 2012

The analysis of the properties and the fields of the applications of multifilamentary superconducting composites is made. Such materials are used to create high field superconducting magnets because they can reach the high value of the critical current density without the loss of the superconductivity. The presented issue contains a review of the important factors governing the choice of superconductors for practical applications. Therefore, the basic theoretical concepts and the formulae required for the laboratory investigation and technical application of these materials are given. The fields of the superconductor's applications are discussed in detail.
Thermal and Mechanical Properties of Copper–Carbon Composites in Electronic Packaging
Authors: Chandra Namas , Silvain Jean‐François , Veillere Amelie , Heintz Jean‐Marc
Published: July 2012

In the field of power electronics, thermal management of silicon chips plays a key role in our ability to increase their performance. It is necessary to dissipate the excess heat in order to prevent heating and consequent deterioration of silicon chips. In this article, we mainly focus on understanding the thermal management requirements of electronic packaging, the key scientific and technological issues, advances in terms of materials, design and processing, and future prospects of the field. In specific, we address how the competing physical, mechanical, and thermal requirements are optimized in heat sinks. Many of the issues addressed can be equally applicable to the design of any component with similar thermal and mechanical requirements including that of heat exchanger tubes. Although, in this article, we focus our attention on copper–carbon system, concepts presented here can be easily extended to other material systems.
3
D
Textile Composites: Mechanical Properties
Authors: Pankow Mark R. , Waas Anthony M.
Published: July 2012

This article discusses many different aspects of 3D woven textile composites. The basics of 3D weaving are introduced along with the fabrication techniques and a discussion of the general types of architectures. Mechanical properties are then examined showing the benefits and drawbacks of the architecture systems. Various different modeling techniques are evaluated including computational techniques that capture architecture‐dependent mechanisms. Finally, the response of 3D woven material is examined under high rates of loading, and its blast and ballistic resistance is discussed.
Temperature and Texture Development during High Speed Friction Stir Processing of Magnesium AZ31
Authors: Hütsch Leon Leander , Hilgert Jakob , Herzberg Klaas , dosSantos Jorge , Huber Norbert
Published: July 2012

The increasing demand for low weight structural materials yields a growing interest in Mg alloys processed at industrially interesting speeds. One aim of this study is to develop defect free welds in the velocity range of 1–10 m · min−1. The resulting welds are subjected to temperature, microstructure and texture investigations. Energy input as well as temperature development under the tool are predicted using numerical models. Image correlation is used to evaluate distortion. The results show that while ensuring constant weld quality, the energy input, sample distortion and grain size can be decreased reaching a threshold at 5 m · min−1. Thermal analysis reveal an asymmetry between AS and RS. The basal planes exhibits a shift from 0 to 45° into processing direction.
A Phosphorescent Nanoparticle‐Based Probe for Sensing and Imaging of (Intra)Cellular Oxygen in Multiple Detection Modalities
Authors: Kondrashina Alina V. , Dmitriev Ruslan I. , Borisov Sergey M. , Klimant Ingo , O'Brien Ian , Nolan Yvonne M. , Zhdanov Alexander V. , Papkovsky Dmitri B.
Published: July 2012

Monitoring cell and tissue oxygenation is important for the analysis of cell development and differentiation, mitochondrial function, and common (patho)physiological conditions such as ischemia, cancer, neurodegenerative disorders. A number of materials for sensing cellular oxygen (O2) by optical means have been described in recent years, but the diverse range of biological models and measurement tasks demands more versatile, flexible, and simple O2 sensors. A new cell‐penetrating phosphorescent nanosensor material called MM2 probe is presented. In it, the highly photostable phosphorescent reporter dye Pt(II)‐5,10,15,20‐tetrakis‐(2,3,4,5,6‐pentafluorophenyl)‐porphyrin (PtTFPP; emission at 650 nm) and poly(9,9‐dioctylfluorene) (PFO) fluorophore act as Förster resonance energy transfer (FRET) donor and two‐photon antennae are embedded in cationic hydrogel nanoparticles. Such probe formulation provides efficient delivery into the cell and subsequent sensing and high‐resolution imaging of cellular O2 in different detection modalities, including ratiometric intensity and phosphorescence lifetime‐based sensing under one‐photon and two photon excitation. MM2 probe combines high brightness, photo‐ and chemical stability, low toxicity, and ease of fabrication and use. Its versatility and analytical performance are demonstrated in physiological experiments with adherent cells and neurospheres representing 2D and 3D respiring objects and detection on time‐resolved fluorescent readers, confocal and multiphoton microscopes, and customized microsecond fluorescence/phosphorescence lifetime imaging microscopy (FLIM) systems.
Surface Chemistry Routes to Modulate the Photoluminescence of Graphene Quantum Dots: From Fluorescence Mechanism to Up‐Conversion Bioimaging Applications
Authors: Zhu Shoujun , Zhang Junhu , Tang Shijia , Qiao Chunyan , Wang Lei , Wang Haiyu , Liu Xue , Li Bo , Li Yunfeng , Yu Weili , Wang Xingfeng , Sun Hongchen , Yang Bai
Published: July 2012

The bandgap in graphene‐based materials can be tuned from 0 eV to that of benzene by changing size and/or surface chemistry, making it a rising carbon‐based fluorescent material. Here, the surface chemistry of small size graphene (graphene quantum dots, GQDs) is tuned programmably through modification or reduction and green luminescent GQDs are changed to blue luminescent GQDs. Several tools are employed to characterize the composition and morphology of resultants. More importantly, using this system, the luminescence mechanism (the competition between both the defect state emission and intrinsic state emission) is explored in detail. Experiments demonstrate that the chemical structure changes during modification or reduction suppresses non‐radiative recombination of localized electron‐hole pairs and/or enhances the integrity of surface π electron network. Therefore the intrinsic state emission plays a leading role, as opposed to defect state emission in GQDs. The results of time‐resolved measurements are consistent with the suggested PL mechanism. Up‐conversion PL of GQDs is successfully applied in near‐IR excitation for bioimaging.
A novel HRAS substitution (c.266C>G; p.S89C) resulting in decreased downstream signaling suggests a new dimension of RAS pathway dysregulation in human development
Authors: Gripp Karen W. , Bifeld Eugenia , Stabley Deborah L. , Hopkins Elizabeth , Meien Stefanie , Vinette Kathy , Sol‐Church Katia , Rosenberger Georg
Published: July 2012

Costello syndrome is caused by HRAS germline mutations affecting Gly12 or Gly13 in >90% of cases and these are associated with a relatively homogeneous phenotype. Rarer mutations in other HRAS codons were reported in patients with an attenuated or mild phenotype. Disease‐associated HRAS missense mutations result in constitutive HRAS activation and increased RAF‐MEK‐ERK and PI3K‐AKT signal flow. Here we report on a novel heterozygous HRAS germline alteration, c.266C>G (p.S89C), in a girl presenting with severe fetal hydrops and pleural effusion, followed by a more benign postnatal course. A sibling with the same mutation and fetal polyhydramnios showed a Dandy–Walker malformation; his postnatal course was complicated by severe feeding difficulties. Their apparently asymptomatic father is heterozygous for the c.266C>G change. By functional analyses we identified reduced levels of active HRASS89C and diminished MEK, ERK and AKT phosphorylation in cells overexpressing HRASS89C, which represent novel consequences of disease‐associated HRAS mutations. Given our patients' difficult neonatal course and presence of this change in their asymptomatic father, we hypothesize that its harmful consequences may be time limited, with the late fetal stage being most sensitive. Alternatively, the phenotype may develop only in the presence of an additional as‐yet‐unknown genetic modifier. While the pathogenicity of the HRAS c.266C>G change remains unproven, our data may illustrate wide functional and phenotypic variability of germline HRAS mutations. © 2012 Wiley Periodicals, Inc.
Central role and mechanisms of β‐cell dysfunction and death in friedreich ataxia–associated diabetes
Authors: Cnop Miriam , Igoillo‐Esteve Mariana , Rai Myriam , Begu Audrey , Serroukh Yasmina , Depondt Chantal , Musuaya Anyishai E. , Marhfour Ihsane , Ladrière Laurence , Moles Lopez Xavier , Lefkaditis Dionysios , Moore Fabrice , Brion Jean‐Pierre , Cooper J. Mark , Schapira Anthony H. V. , Clark Anne , Koeppen Arnulf H. , Marchetti Piero , Pandolfo Massimo , Eizirik Décio L. , Féry Françoise
Published: July 2012

Objective:

Friedreich ataxia (FRDA) is an autosomal recessive neurodegenerative disease caused in almost all cases by homozygosity for a GAA trinucleotide repeat expansion in the frataxin gene. Frataxin is a mitochondrial protein involved in iron homeostasis. FRDA patients have a high prevalence of diabetes, the pathogenesis of which is not known. We aimed to evaluate the relative contribution of insulin resistance and β‐cell failure and the pathogenic mechanisms involved in FRDA diabetes.

Methods:

Forty‐one FRDA patients, 26 heterozygous carriers of a GAA expansion, and 53 controls underwent oral and intravenous glucose tolerance tests. β‐Cell proportion was quantified in postmortem pancreas sections from 9 unrelated FRDA patients. Using an in vitro disease model, we studied how frataxin deficiency affects β‐cell function and survival.

Results:

FRDA patients had increased abdominal fat and were insulin resistant. This was not compensated for by increased insulin secretion, resulting in a markedly reduced disposition index, indicative of pancreatic β‐cell failure. Loss of glucose tolerance was driven by β‐cell dysfunction, which correlated with abdominal fatness. In postmortem pancreas sections, pancreatic islets of FRDA patients had a lower β‐cell content. RNA interference–mediated frataxin knockdown impaired glucose‐stimulated insulin secretion and induced apoptosis in rat β cells and human islets. Frataxin deficiency sensitized β cells to oleate‐induced and endoplasmic reticulum stress‐induced apoptosis, which could be prevented by the incretins glucagon‐like peptide‐1 and glucose‐dependent insulinotropic polypeptide.

Interpretation:

Pancreatic β‐cell dysfunction is central to diabetes development in FRDA as a result of mitochondrial dysfunction and higher sensitivity to metabolic and endoplasmic reticulum stress‐induced β‐cell death. ANN NEUROL 2012;72:971–982
Protective effects of enalapril, an angiotensin‐converting enzyme inhibitor, on multiple organ damage following scald injury in rats
Authors: Zhang Bing‐Qian , Wang Guang , Zhang Jia‐Ping , Hu Jiong‐Yu , Xiao Rong , Lei Ze‐Yuan , Ruan Jing , Dang Yong‐Ming , Zhang Dong‐Xia , Bian Xiu‐Wu , Huang Yue‐Sheng
Published: July 2012

The aim of this study is to investigate the effects of enalapril, an angiotensin‐converting enzyme inhibitor, on multiple organ damage after scald injury. Healthy adult rats (half male and half female; 8–12 weeks old) were randomly assigned to the following treatments: sham operation, scald injury, and intraperitoneal enalapril (1, 2, and 4 mg/kg body weight) treatment after scalding. At 1, 12, and 24 H postscald, left ventricular and aortic hemodynamics were measured using a multichannel physiological recorder. Functional and pathological changes of the heart, liver, and kidney were examined by biochemical and histological methods. Compared with sham controls, untreated scalded animals showed decreased hemodynamic parameters and increased myocardial angiotensin II, serum creatine kinase heart isoenzyme, and serum cardiac troponin I and histopathological inflammation in the myocardium 12 H postscald. These hemodynamic, functional, and pathological changes were attenuated by 1 mg/kg enalapril. Enalapril reversed scald‐induced elevations in aspartate aminotransferase, alanine aminotransferase, blood urea nitrogen, and blood creatinine 12 H postscald, and ameliorated focal necrosis in the liver and erythrocyte cast formation in renal tubules. However, higher doses of enalapril yielded less or no improvement in organ dysfunction. Enalapril at 1 mg/kg attenuates scald‐induced multiple organ damage in rats.
In silico prediction of drug dissolution and absorption with variation in intestinal pH for BCS class II weak acid drugs: ibuprofen and ketoprofen
Authors: Tsume Yasuhiro , Langguth Peter , Garcia‐Arieta Alfredo , Amidon Gordon L.
Published: July 2012

The FDA Biopharmaceutical Classification System guidance allows waivers for in vivo bioavailability and bioequivalence studies for immediate‐release solid oral dosage forms only for BCS class I. Extensions of the in vivo biowaiver for a number of drugs in BCS class III and BCS class II have been proposed, in particular, BCS class II weak acids. However, a discrepancy between the in vivo BE results and in vitro dissolution results for BCS class II acids was recently observed. The objectives of this study were to determine the oral absorption of BCS class II weak acids via simulation software and to determine if the in vitro dissolution test with various dissolution media could be sufficient for in vitro bioequivalence studies of ibuprofen and ketoprofen as models of carboxylic acid drugs. The oral absorption of these BCS class II acids from the gastrointestinal tract was predicted by GastroPlus™. Ibuprofen did not satisfy the bioequivalence criteria at lower settings of intestinal pH of 6.0. Further the experimental dissolution of ibuprofen tablets in a low concentration phosphate buffer at pH 6.0 (the average buffer capacity 2.2 mmol l ‐1/pH) was dramatically reduced compared with the dissolution in SIF (the average buffer capacity 12.6 mmol l ‐1/pH). Thus these predictions for the oral absorption of BCS class II acids indicate that the absorption patterns depend largely on the intestinal pH and buffer strength and must be considered carefully for a bioequivalence test. Simulation software may be a very useful tool to aid the selection of dissolution media that may be useful in setting an in vitro bioequivalence dissolution standard. Copyright © 2012 John Wiley & Sons, Ltd.
Mutations in Lyar and p53 are synergistically lethal in female mice
Authors: Wang Guan , Fulkerson Christopher M. , Malek Reem , Ghassemifar Sara , Snyder Paul W. , Mendrysa Susan M.
Published: July 2012

BACKGROUND

Ly‐1 antibody reactive clone (LYAR) is a nucleolar zinc finger protein that has been implicated in cell growth, self‐renewal of embryonic stem cells, and medulloblastoma. To test whether LYAR is critical for cell growth and development, we generated Lyar mutant mice.

METHODS

Mice carrying the mutant Lyargt allele were generated from embryonic stem cells that contained a gene‐trap insertion in the Lyar gene. Phenotypic analyses were performed on Lyar mutant mice and mouse embryonic fibroblasts. Lyargt/gt mice were crossed to mice lacking the p53 tumor suppressor protein and Lyar/p53 compound mutants scored for external abnormalities.

RESULTS

Lyargt/gt homozygotes are viable, fertile, and indistinguishable from wild type littermates. However, the growth of Lyar+/gt and Lyargt/gt mouse embryonic fibroblasts (MEFs) was impaired, coincident with an increase in the steady‐state level of p53 and a key p53 effector of growth arrest, p21, suggesting that a cellular stress response is triggered in the absence of a wild type level of LYAR. Remarkably, the majority of Lyar+/gt and Lyargt/gt female mice lacking p53 mice failed to survive. The neural tube defect (NTD) exencephaly was observed in ≈26% and ≈61% of female Lyar+/gt;p53−/− and Lyargt/gt;p53−/− embryos, respectively.

CONCLUSIONS

Lyar/p53 mutant mice represent a new digenic model of NTDs. Furthermore, these studies identify Lyar as a novel candidate gene for a role in human NTDs. These results provide new data to support the idea that loss of a p53‐mediated developmental checkpoint may increase the risk of NTDs owing to some germline mutations. © Birth Defects Research (Part A) 94:729–737, 2012. Published 2012 Wiley Periodicals, Inc.
A novel application of contrast echocardiography to exclude active coronary perforation bleeding in patients with pericardial effusion
Authors: Bagur Rodrigo , Bernier Mathieu , Kandzari David E. , Karmpaliotis Dimitri , Lembo Nicholas J. , Rinfret Stéphane
Published: July 2012

Management of hemodynamically significant cardiac tamponade will most often require pericardial drainage. In the absence of hemodynamic evidence of tamponade, however, management of a pericardial effusion represents a clinical dilemma. Pericardial leakage of blood may be transient, and extravasation may have stopped by time of echocardiographic assessment. Besides its usefulness in ischemic heart disease, contrast echocardiography might be applied in the context of coronary perforations. We report the use of contrast echocardiography in four cases of coronary perforation without overt signs of cardiac tamponade as a tool to streamline decision making as to whether perform pericardiocentesis or not. Our series demonstrate the clinical utility and effectiveness of echocardiographic contrast imaging to confirm or exclude active bleeding into the pericardial space when not otherwise visible by conventional imaging measures. © 2012 Wiley Periodicals, Inc.
Microarray analysis of Xenopus endoderm expressing Ptf1a
Authors: Bilogan Cassandra K. , Horb Marko E.
Published: July 2012

Pancreas‐specific transcription factor 1a (Ptf1a), a bHLH transcription factor, has two temporally distinct functions during pancreas development; initially it is required for early specification of the entire pancreas, while later it is required for proper differentiation and maintenance of only acinar cells. The importance of Ptf1a function was revealed by the fact that loss of Ptf1a leads to pancreas agenesis in humans. While Ptf1a is one of the most important pancreatic transcription factors, little is known about the differences between the regulatory networks it controls during initial specification of the pancreas as opposed to acinar cell development, and to date no comprehensive analysis of its downstream targets has been published. In this article, we use Xenopus embryos to identify putative downstream targets of Ptf1a. We isolated anterior endoderm tissue overexpressing Ptf1a at two early stages, NF32 and NF36, and compared their gene expression profiles using microarrays. Our results revealed that Ptf1a regulates genes with a wide variety of functions, providing insight into the complexity of the regulatory network required for pancreas specification. genesis 50:853–870, 2012. © 2012 Wiley Periodicals, Inc.
Joint Genotype Calling With Array and Sequence Data
Authors: O'Connell Jared , Marchini Jonathan
Published: July 2012

Analysis of rare variants is currently a major focus of genetic studies of human disease. Single‐nucleotide polymorphism (SNP) genotypes can be assayed using microarray genotyping or by sequencing, but neither technology produces perfect genotype calls, especially at rare SNPs. Studies that collect both types of data are becoming increasingly common, so it may be possible to combine data types to increase accuracy. We present a method, called Chiamante, which calls genotypes on individuals with either array data, sequence data, or both. The model adapts to data quality and can estimate when either the array or the sequence data should be ignored when calling the genotypes at each SNP. As a special case, our method will call genotypes from only array data and outperforms existing methods in this scenario. We have applied our method to array and sequence data from Phase I of the 1000 Genomes Project and show that it provides improved performance, especially at rare SNPs. This method provides a foundation for future efforts to fuse genetic data from different sources, for example, when combining data from exome sequencing and exome microarrays.
Reading acquisition reorganizes the phonological awareness network only in alphabetic writing systems
Authors: Brennan Christine , Cao Fan , Pedroarena‐Leal Nicole , McNorgan Chris , Booth James R.
Published: July 2012

It is unknown how experience with different types of orthographies influences the neural basis of oral language processing. In order to determine the effects of alphabetic and nonalphabetic writing systems, the current study examined the influence of learning to read on oral language in English and Chinese speakers. Children (8–12 years olds) and adults made rhyming judgments to pairs of spoken words during functional magnetic resonance imaging (fMRI). Developmental increases were seen only for English speakers in the left hemisphere phonological network (superior temporal gyrus (STG), inferior parietal lobule, and inferior frontal gyrus). The increase in the STG was more pronounced for words with conflicting orthography (e.g. pint‐mint; jazz‐has) even though access to orthography was irrelevant to the task. Moreover, higher reading skill was correlated with greater activation in the STG only for English speaking children. The effects suggest that learning to read reorganizes the phonological awareness network only for alphabetic and not logographic writing systems because of differences in the principles for mapping between orthographic and phonological representations. The reorganization of the auditory cortex may result in better phonological awareness skills in alphabetic readers. Hum Brain Mapp 34:3354–3368, 2013. © 2012 Wiley Periodicals, Inc.
TIE2-expressing monocytes as a diagnostic marker for hepatocellular carcinoma correlates with angiogenesis
Authors: Matsubara Tokuhiro , Kanto Tatsuya , Kuroda Shoko , Yoshio Sachiyo , Higashitani Koyo , Kakita Naruyasu , Miyazaki Masanori , Sakakibara Mitsuru , Hiramatsu Naoki , Kasahara Akinori , Tomimaru Yoshito , Tomokuni Akira , Nagano Hiroaki , Hayashi Norio , Takehara Tetsuo
Published: July 2012

Angiogenesis is a critical step in the development and progression of hepatocellular carcinoma (HCC). Myeloid lineage cells, such as macrophages and monocytes, have been reported to regulate angiogenesis in mouse tumor models. TIE2, a receptor of angiopoietins, conveys pro-angiogenic signals and identifies a monocyte/macrophage subset with pro-angiogenic activity. Here, we analyzed the occurrence and kinetics of TIE2-expressing monocytes/macrophages (TEMs) in HCC patients. This study enrolled 168 HCV-infected patients including 89 with HCC. We examined the frequency of TEMs, as defined as CD14+CD16+TIE2+ cells, in the peripheral blood and liver. The localization of TEMs in the liver was determined by immunofluorescence staining. Micro-vessel density in the liver was measured by counting CD34+ vascular structures. We found that the frequency of circulating TEMs was significantly higher in HCC than non-HCC patients, while being higher in the liver than in the blood. In patients who underwent local radio-ablation or resection of HCC, the frequency of TEMs dynamically changed in the blood in parallel with HCC recurrence. Most TEMs were identified in the perivascular areas of tumor tissue. A significant positive correlation was observed between micro-vessel density in HCC and frequency of TEMs in the blood or tumors, suggesting that TEMs are involved in HCC angiogenesis. Receiver operating characteristic analyses revealed the superiority of TEM frequency to AFP, PIVKA-II and ANG-2 serum levels as diagnostic marker for HCC. Conclusion: TEMs increase in patients with HCC and their frequency changes with the therapeutic response or recurrence. We thus suggest that TEM frequency can be used as a diagnostic marker for HCC, potentially reflecting angiogenesis in the liver.
Incidence, risk factors and management of pleural effusions during dasatinib treatment in unselected elderly patients with chronic myelogenous leukaemia
Authors: Latagliata Roberto , Breccia Massimo , Fava Carmen , Stagno Fabio , Tiribelli Mario , Luciano Luigiana , Gozzini Antonella , Gugliotta Gabriele , Annunziata Mario , Cavazzini Francesco , Ferrero Dario , Musto Pellegrino , Capodanno Isabella , Iurlo Alessandra , Visani Giuseppe , Crugnola Monica , Calistri Elisabetta , Castagnetti Fausto , Vigneri Paolo , Alimena Giuliana
Published: July 2012

To assess the most important features and clinical impact of pleural effusions, which are a common toxicity during dasatinib treatment and often impair its high efficacy, 172 unselected consecutive patients with chronic myelogenous leukaemia in chronic phase treated in 27 Italian centres, with dasatinib when aged >60 years for resistance/intolerance to imatinib, were examined. During treatment, 52/172 patients (30.2%) presented pleural effusion, which was grades 1–2 in 38 patients and grades 3–4 in 14 patients (8.1% of the entire cohort of patients), according to the WHO scale; in 14/52 patients (26.9%), there was a concomitant pericardial effusion. Pleural effusion was recurrent in 25/52 patients (48.0%). Median time from dasatinib to first pleural effusion was 11.0 months (interquartile range 3.6–18.6). Eleven patients (6.4%) required permanent dasatinib discontinuation. Only presence of concomitant pulmonary disease ( p = 0.035) and initial daily dose of dasatinib (140 mg vs 100 mg, p = 0.014) were significantly associated with pleural effusions. There were no differences among patients with or without pleural effusions as concerns response rates and overall survival. Pleural effusions were common in our unselected ‘real‐life’ population of elderly patients but were clinically manageable and did not seem to affect treatment results. Copyright © 2012 John Wiley & Sons, Ltd.
Construction and hemocompatibility study of highly bioactive heparin‐functionalized surface
Authors: Yang Zhi‐Lu , Zhou Shuo , Lu Lei , Wang Xin , Wang Jin , Huang Nan
Published: July 2012

A simple method is developed to construct anticoagulant surfaces via passive adsorption of heparin onto the protonated plasma‐polymerized allylamine (PPAam) films from phosphate‐buffered saline (PBS). These protonated PPAam surfaces are found to have high affinity to heparin. Importantly, the heparin‐functionalized PPAam (Hep–PPAam) surfaces show good retention of heparin after long‐term immersion in PBS. The Hep–PPAam surface prolongs the activated partial thromboplastin time for about 20 s as compared to 316L stainless steel even though the adsorption amount of heparin is only about 300 ng/cm2. This indicates that the heparin bound to the protonated PPAam surfaces in this way maintains a high bioactivity. Blood platelet adhesion and activation on this surface is remarkably reduced and adsorption and activation of fibrinogen is inhibited. Thus, Hep–PPAam surface modification leads to a significant improve of the hemocompatibility. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 100A:3124–3133, 2012.
Histocompatibility and in vivo signal throughput for PEDOT, PEDOP, P3MT, and polycarbazole electrodes
Authors: Forcelli Patrick A. , Sweeney Cameron T. , Kammerich Anthony D. , Lee Brian C.‐W. , Rubinson Laura H. , Kayinamura Yohani P. , Gale Karen , Rubinson Judith F.
Published: July 2012

Stimulation and recording of the in vivo electrical activity of neurons are critical functions in contemporary biomedical research and in treatment of patients with neurological disorders. The electrodes presently in use tend to exhibit short effective lifespans due to degradation of signal transmission resulting from the tissue response at the electrode–brain interface, with signal throughput suffering most at the low frequencies relevant for biosignals. To overcome these limitations, new electrode designs to minimize tissue responses, including conducting polymers (CPs) have been explored. Here, we report the short‐term histocompatibility and signal throughput results comparing platinum and CP‐modified platinum electrodes in a Sprague–Dawley rat model. Two of the polymers tested elicited significantly decreased astrocyte responses relative to platinum. These polymers also showed improved signal throughput at low frequencies and comparable signal‐to‐noise ratios during targeted intracranial electroencephalograms. These results suggest that CP electrodes may present viable alternatives to the metal electrodes that are currently in use. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 100A:3455–3462, 2012.
Reversine promotes porcine muscle derived stem cells (PMDSCs) differentiation into female germ‐like cells
Authors: Lv Xiao , Zhu Haijing , Bai Yaofu , Chu Zhili , Hu Yue , Cao Hui , Liu Chao , He Xin , Peng Sha , Gao Zhimin , Yang Chunrong , Hua Jinlian
Published: July 2012

A small molecular chemical‐Reversine has been shown to promote cell reprogramming and induce dedifferentiation of multiple terminally differentiated mesodermal origin cells, and then differentiate into other cell types within mesodermal lineages as well as neuroectodermal. However, the possibilities of these cells to give rise to germ cell lineages have not been examined. The objective of the current study was to detect the effect of Reversine on PMDSCs differentiation into germ cells. PMDSCs from fetal porcine skeletal muscle and their potential of differentiation into germ cells in vitro were investigated. The phenotype, proliferation potential, characteristic markers of the first adhesion cells (pp1), and the purified 2 times cells (pp3) were analyzed by growth curve, FACS, and RT‐PCR, respectively. Then, the purified cells were induced with 10% or 20% bovine follicular fluid (FF), the results showed that some of the induced pp3 cells were similar as porcine oocyte, and expressed germ cell and oocyte markers analyzed by semi‐quantitative RT‐PCR and immunofluorescent staining. Reversine clearly increased the potentiality of PMDSCs differentiation into large round germ‐like cells in FF induction medium analyzed by morpholgogy, QRT‐PCR and immunofluoresce. The BrdU labeled PMDSCs might differentiate into female germ‐like cells in recipient's kidney capsule, which were positive for germ cell and meiotic markers (Dazl, Vasa, Figla, Stra8, Scp3) and oocyte markers (Zp2, Zp3). These findings provided an efficient model to study the mechanism of cell proliferation and germ cell differentiation in livestock promoted by Reversine. J. Cell. Biochem. 113: 3629–3642, 2012. © 2012 Wiley Periodicals, Inc.
A Novel Pattern of Placental Leucine Transfer During Mid to Late Gestation in a Highly Placentotrophic Viviparous Lizard
Authors: Itonaga Keisuke , Wapstra Erik , Jones Susan M.
Published: July 2012

Placentotrophy is the nourishment of embryos by resources provided via the placenta during gestation. The magnitude and timing of placental nutrient support during pregnancy are important for embryonic growth, especially in highly placentotrophic animals such as mammals. However, no study has yet investigated how placental organic nutrient support may change during pregnancy in highly placentotrophic viviparous reptiles. Amino acids are essential nutrients for embryonic growth and leucine is a common amino acid. The magnitude and timing of placental leucine transfer may affect embryonic growth and mass and, therefore, offspring phenotype. In this study, female Pseudemoia entrecasteauxii, a highly placentotrophic viviparous skink, were collected throughout gestation. We injected 3H‐leucine into these gravid females and assessed the transfer of 3H‐leucine into maternal compartments (i.e., the blood and the liver), and into embryonic compartments (i.e., the embryo, the yolk, and the amniotic fluid). At either 60 or 120 min post‐injection, the radioactivity in each sample was extracted and then counted, and the transfer ratio was calculated. Our results provide direct evidence that circulating maternal leucine passes through the placenta into the embryos in this species. The relative rate of placental leucine transfer did not alter during mid to late gestation. This suggests the steady somatic growth of the embryos during mid‐late pregnancy is dependent upon the placental transfer of nutrients rather than yolk stores. This pattern of placental nutrient support may determine offspring body size at birth and, therefore, offspring fitness in P. entrecasteauxii. J. Exp. Zool. (Mol. Dev. Evol.) 318:308–315, 2012. © 2012 Wiley Periodicals, Inc.
The evolution, development and skeletal identity of the crocodylian pelvis: Revisiting a forgotten scientific debate
Authors: Claessens Leon P.A.M. , Vickaryous Matthew K.
Published: July 2012

Unlike most tetrapods, in extant crocodylians the acetabulum is formed by only two of the three skeletal elements that constitute the pelvis, the ilium, and ischium. This peculiar arrangement is further confused by various observations that suggest the crocodylian pelvis initially develops from four skeletal elements: the ilium, ischium, pubis, and a novel element, the prepubis. According to one popular historical hypothesis, in crocodylians (and many extinct archosaurs), the pubis fuses with the ischium during skeletogenesis, leaving the prepubis as a distinct element, albeit one which is excluded from the acetabulum. Whereas the notion of a distinct prepubic element was once a topic of considerable interest, it has never been properly resolved. Here, we combine data gleaned from a developmental series of Alligator mississippiensis embryos, with a revised interpretation of fossil evidence from numerous outgroups to Crocodylia. We demonstrate that the modern crocodylian pelvis is composed of only three elements: the ilium, ischium, and pubis. The reported fourth pelvic element is an unossified portion of the ischium. Interpretations of pelvic skeletal homology have featured prominently in sauropsid systematics, and the unambiguous identification of the crocodylian pubis provides an important contribution to address larger scale evolutionary questions associated with locomotion and respiration. J. Morphol. , 2012. © 2012 Wiley Periodicals, Inc.
Ultra sensitive surface‐enhanced Raman scattering detection based on monolithic column as a new type substrate
Authors: Li Qingqing , Du Yiping , Tang Huirong , Wang Xuan , Chen Guiping , Iqbal Jibran , Wang Wenming , Zhang Weibing
Published: July 2012

A novel ultrasensitive detection method utilizing surface‐enhanced Raman scattering (SERS) based on monolithic column was developed in the present study. Monolithic column is a kind of chromatographic stationary phase that contains highly interconnected pores and absorbs chemical components efficiently. Dropping a mixture solution containing analyte, silver colloid, and NaCl on the surface in advance, SERS signals were collected on the surface of the monolithic column. With this method, five commonly used probe molecules of Rhodamine 6G (R6G), p‐aminothiophenol, Rhodamine 123, crystal violet, thymine, and two chemicals that are used in agriculture (paraquat and flusilazole) were detected. Especially, R6G and p‐aminothiophenol can be detected at extremely low concentrations of 10–18 and 10–16 mol/L at milliliter level, respectively. The enhancement factor was calculated to be approximately 1014 for R6G detection. The results suggest that the monolithic column does improve the sensitivity of SERS detection dramatically and the topography of the monolithic column is essential for the enhancement. The easy operability and the significant enhancement are the greatest advantages of this method. Copyright © 2012 John Wiley & Sons, Ltd.
Effects of the agglomeration state on the Raman properties of Co3O4 nanoparticles
Authors: Lorite I. , Romero J. J. , Fernández J. F.
Published: July 2012

The features of the Raman spectra of Co3O4 30‐nm nanoparticles depend strongly on their agglomeration state. When measured at low incident laser power, the spectrum of isolated nanoparticles corresponds to that found in bulk materials, whereas the agglomerated nanoparticles present a clear red‐shift and broadening of the Raman bands. On the other hand, when measured at even lower power, both agglomerated and isolated nanoparticles show the same spectrum of microscopic particles. These effects have been studied by variations of the 532‐nm laser power and the environmental temperature. The thermal dependence of Raman spectra of agglomerated nanoparticles is different to that of isolated nanoparticles but is comparable to the one of bulk material. The different behaviour of the nanoparticles at different agglomeration state is associated to the transmission of phonons among the particles. On the other hand, an increase of the laser power causes a larger number of acoustic phonons, producing a variation of the vibration anharmonicity of the nanoparticles. This increase is more pronounced in the agglomerated nanoparticles, due to the transmission of phonons, causing a much intense modification of the Raman spectrum produced by the laser power. These results clearly indicate that the agglomeration state of the nanoparticles affects their Raman properties. Copyright © 2012 John Wiley & Sons, Ltd.
Field Raman analysis to diagnose the conservation state of excavated walls and wall paintings in the archaeological site of Pompeii (Italy)
Authors: Maguregui Maite , Knuutinen Ulla , Martínez‐Arkarazo Irantzu , Giakoumaki Anastasia , Castro Kepa , Madariaga Juan M.
Published: July 2012

This work presents the results of field Raman analyses, assisted by a hand‐held energy dispersive‐X‐ray fluorescence spectrometer, to experimentally determine the composition of compounds present in the walls and wall paintings of two Pompeian houses, one with many luxurious decorative elements (the House of Marcus Lucretius, Regio IX, Insula 3, House 5/24) and a more modest building (Regio IX, Insula 3, House 1–2). These houses were excavated 150 years ago, and the majority of the rooms have been exposed outdoors. The chemical attacks of the acid gases and the biological colonisation can be considered the most serious problems of the archaeological remains from Insula IX 3 of Pompeii. The walls and wall paintings exposed to the rain‐wash are the worst preserved ones, probably due to a continuous cycle of SO2 attack to the original materials, involving loss of plaster. This severe decay was not observed in the rooms covered by roofs; in these last rooms, the most noticeable pathologies are the presence of high humidity in the walls and the elevated amount of efflorescences. Copyright © 2012 John Wiley & Sons, Ltd.
Accounting for correlation in network meta‐analysis with multi‐arm trials
Authors: Franchini A. J. , Dias S. , Ades A. E. , Jansen J. P. , Welton N. J.
Published: July 2012

Multi‐arm trials (trials with more than two arms) are particularly valuable forms of evidence for network meta‐analysis (NMA). Trial results are available either as arm‐level summaries, where effect measures are reported for each arm, or as contrast‐level summaries, where the differences in effect between arms compare with the control arm chosen for the trial. We show that likelihood‐based inference in both contrast‐level and arm‐level formats is identical if there are only two‐arm trials, but that if there are multi‐arm trials, results from the contrast‐level format will be incorrect unless correlations are accounted for in the likelihood. We review Bayesian and frequentist software for NMA with multi‐arm trials that can account for this correlation and give an illustrative example of the difference in estimates that can be introduced if the correlations are not incorporated. We discuss methods of imputing correlations when they cannot be derived from the reported results and urge trialists to report the standard error for the control arm even if only contrast‐level summaries are reported. Copyright © 2012 John Wiley & Sons, Ltd.