bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation and Characterization of Fe2O3/Ammonium Perchlorate (AP) Nanocomposites through Ceramic Membrane Anti‐Solvent Crystallization
Authors: Ma Zhenye , Wu Rujun , Song Jun , Li Cheng , Chen Rizhi , Zhang Lixiong 
Published: April 2012

AbstractA novel ceramic membrane anti‐solvent crystallization (CMASC) method was proposed to prepare Fe2O3/AP nanocomposites with core‐shell structure. For the preparation of Fe2O3/AP nanocomposites, several key advantages of the CMASC method are as follows. Firstly, both well‐dispersed Fe2O3 nanoparticles and the superfine AP preparation can be achieved at one step. Secondly, no non‐component of solid propellant was involved in this composite process. Thirdly, the size and morphology of Fe2O3/AP nanocomposites can be effectively controlled by using the ceramic membrane with regular pore structure as feeding template. The morphology and structure of Fe2O3/AP nanocomposites were characterized by inductively coupled plasma spectrophotometry (ICP), IR spectroscopy, SEM, and HRTEM. The results verified that the size and morphology of Fe2O3/AP nanocomposites are controllable, and the dispersion of Fe2O3 nanoparticles is greatly improved in Fe2O3/AP nanocomposites. Moreover, the thermal decomposition of the as‐prepared Fe2O3/AP nanocomposites was measured with TG‐DSC. The results showed that the Fe2O3 nanoparticles in Fe2O3/AP nanocomposites exhibit better catalytic activity on the thermal decomposition of AP. In addition, the mechanism was also discussed.
Synthesis, Structure, and Explosive Properties of a New Trinitrate Derivative of an Unexpected Condensation Product of Nitromethane with Glyoxal
Authors: Cudziło Stanisław , Nita Marcin , Chołuj Artur , Szala Mateusz , Danikiewicz Witod , Spólnik Grzegorz , Krompiec Stanisław , Michalik Sławomir , Krompiec Michał , Świtlicka Anna 
Published: April 2012

AbstractIn the condensation reaction of nitromethane with glyoxal carried out in an aqueous solution of sodium hydroxide, 3,6‐dinitro‐cyclohexane‐1,2,4,5‐tetraol was obtained (the expected product, described in the literature) and, unexpectedly, also tricyclic nitro‐triol (6b‐nitrohexahydro‐2H‐1,3,5‐trioxacyclopenta[cd]‐pentalene‐2,4,6‐triol), which has been unknown until now, was obtained as the main product. The structure of the compound was confirmed with1H NMR and13C NMR spectroscopy, LR, and HR‐MS techniques and with single‐crystal X‐ray diffractometry. The tricyclic triol (formally a hemiacetal) was transformed into 6b‐nitrohexahydro‐2H‐1,3,5‐trioxacyclopenta[cd]‐pentalene‐2,4,6‐triyl trinitrate by reaction with 98 % HNO3. Some explosive properties of this compound were determined including: friction and impact sensitivity, activation energy, detonation velocity, heat of combustion in an oxygen atmosphere and enthalpy of formation. The nitrate ester is a powerful explosive with performance close to that of pentaerythritol tetranitrate (PETN).
Impacts of chemical crop protection applications on related CO2 emissions and CO2 assimilation of crops
Authors: Kern Manfred , Noleppa Steffen , Schwarz Gerald 
Published: April 2012

AbstractBACKGROUND: A major global challenge is to provide agricultural production systems that are able to sustain growing demands for food, feed, fibre and renewable raw materials without exacerbating climate change. Detailed and reliable data on the CO2 balance of different agricultural management activities and inputs as a basis to quantify carbon footprints of agriculture are still lacking. This study aims to fill this gap further by quantifying the net balance of emitted and assimilated CO2 due to the application of crop protection treatments on the farm, and by assessing their partial contribution to GHG emissions and mitigation in agriculture. The study focuses on key agricultural crops including wheat, corn, oilseeds and sugar crops.RESULTS: The final CO2 balance, considering GHG emissions due to on‐farm CPP treatment in comparison with CO2 storage in additional biomass, CO2 protected with respect to agrotechnical inputs and land inputs and CO2 saved with respect to associated global land use changes, is positive and may reach multiples of up to nearly 2000.CONCLUSION: The results highlight the importance of the positive yield effects of the CPP programme applications on the farm, resulting in additional assimilated biomass at the farm level and less land use changes at the global level, and thus lower pressure on environmentally important indicators of overall agricultural sustainability. Copyright © 2012 Society of Chemical Industry
Knockdown of several components of cytochrome P450 enzyme systems by RNA interference enhances the susceptibility of Helicoverpa armigera to fenvalerate
Authors: Tang Tao , Zhao Chunqing , Feng Xiaoyun , Liu Xueyuan , Qiu Lihong 
Published: April 2012

AbstractBACKGROUND: The function of cytochrome P450 proteins (P450s) in the metabolism of a variety of compounds by oxidation and reduction is well elucidated, but its interactions with other electron transfer components in the pyrethroid resistance of insect pests have been a mystery for a long time. In previous studies the authors cloned and characterised CYP6B7 and cytochrome b5 (Cyt‐b5) in the fenvalerate‐resistant HDFR strain of cotton bollworm (Helicoverpa armigera Hübner) and showed that CYP6B7 mRNA was overexpressed and important for resistance to fenvalerate. In the present study, the functional interactions of CYP6B7, NADPH‐dependent cytochrome P450 reductase (CPR) and Cyt‐b5 were assessed using RNA interference (RNAi) strategies and monitoring for fenvalerate resistance levels.RESULTS: RT‐qPCR analyses indicated that the expression levels of CYP6B7, CPR and Cyt‐b5 mRNA were decreased drastically in the midgut of fourth‐instar larvae of the H. armigera HDFR strain after corresponding double‐stranded RNA (dsRNA) injection, compared with that of the control. The knockdown of CYP6B7, CPR and Cyt‐b5 transcripts was time course dependent during a 12–48 h period after dsRNA injection. At the earlier time points analysed, significant suppression of CYP6B7 mRNA levels was observed in larvae injected with dsCYP6B7‐313 as compared with controls, and further suppression was observed in larvae injected with dsCYP6B7‐313, dsCPR‐403 and dsCyt‐b5. The injection of dsCYP6B7‐313 together with dsCPR‐403 and dsCyt‐b5 increased larval susceptibility of the HDFR strain to fenvalerate.CONCLUSION: The results demonstrated that silencing of CYP6B7 alone or CYP6B7 together with CPR and/or Cyt‐b5 increased the susceptibility of H. armigera to fenvalerate, suggesting that CYP6B7, CPR and Cyt‐b5 collaboratively participated in enhanced metabolism of fenvalerate and played an important role in the resistance of H. armigera to fenvalerate. Copyright © 2012 Society of Chemical Industry
Amorphous phase of GeTe‐based phase‐change memory alloys: Polyvalency of GeTe bonding and polyamorphism
Authors: Kolobov Alexander V. , Fons Paul , Krbal Milos , Tominaga Junji 
Published: April 2012

AbstractThe structure of the amorphous phase of GeTe‐based phase‐change materials is discussed. Comparison of the Ge(4):Te(2) and Ge(3):Te(3) configurations present in the amorphous phase suggests that the former is locally more stable while the latter can lower its energy due to ‘resonance’ interactions in structures within more extended order. We further demonstrate that polyvalency of the GeTe bonds can lead to the formation of negative‐U defects accounting for the high resistivity of the amorphous phase. Finally, polyamorphysm of the amorphous phase of Ge2Sb2Te5 is discussed.
Lattice dynamics and dielectric response of Ba0.4Sr0.6−yMnyTiO3 ceramics in a wide frequency range
Authors: Zhang Jingji , Zhai Jiwei , Xu Zhengkui , Zhang Yewen 
Published: April 2012

AbstractLattice dynamics and dielectric behavior in a wide frequency range of Ba0.4Sr0.6−yMnyTiO3 ceramics were investigated by using infrared (IR) spectroscopy and dielectric measurements. X‐ray diffraction results revealed that only perovskite phase was visible for all compositions. Mn occupied A‐site preferably as Mn2+ when y ≤ 0.02; whereas when y ≥ 0.05, Mn occupied B‐site and was oxidized to Mn3+. Dielectric measurements and IR analysis indicated that the hardening of the softest mode was not remarkable with increasing Mn concentration, which resulted in an unremarkable change in tunability. Compared to the samples with y ≤ 0.02, those with y ≥ 0.05 had a higher fitted damping factor, resulting from the distortion of the perovskite lattice caused by the incorporation of Mn at the Ti‐site, which led to a low intrinsic quality factor.
Quantum criticality in CaRuO3 – Influence of Ti substitution
Authors: Baran A. , Zorkovská A. , Kajňaková M. , Šebek J. , Šantavá E. , Bradarić I. , Feher A. 
Published: April 2012

AbstractThermodynamic and transport properties of the CaRu1–xTixO3 system with x = 0, 0.03, 0.07, 0.10, and 0.15 in magnetic field up to 9 T have been studied. The unconventional temperature dependences of magnetic susceptibility, specific heat, and electrical resistivity observed for CaRuO3 are typical for non‐Fermi liquids and they support the assumption about the proximity of the system to the quantum critical point. The analysis of the experimental results suggests the electronic phase separation in CaRuO3 into ferromagnetic itinerant regions coexisting with strongly correlated ones. Substitution by titanium seems to push the system towards ferromagnetism, and drives it away from the quantum criticality.
Texture mechanisms and microstructure of biaxial thin films grown by oblique angle deposition
Authors: Shetty A. R. , Karimi A. 
Published: April 2012

AbstractIn order to understand the texture formation mechanism in thin films grown under oblique angle deposition (OAD), TiAlN films were deposited at room temperature (RT) under various incident angles. We show that both in‐plane and out‐of‐plane crystallographic orientations respond strongly to the deposition angle. For α = 0°, the pole figures show a (111) and (200) mixed out‐of‐plane orientation with random in‐plane alignment. In contrast, under OAD, inclined textures are observed with the (111) direction moving toward the incident flux direction and the (200) moving away, showing substantial in‐plane alignment. This observation suggests that TiAlN crystals prefer to grow with the (200) direction perpendicular to the substrate while maintaining the minimization of the surface free energy by maximizing the (111) surface area toward the incident flux. The in‐plane texture, which is randomly oriented at normal incidence, gives rise to two preferred orientations under oblique angles – one along the direction of flux and other away from the deposition source. The biaxial texture results from a competition among texture mechanism related to surface mobilities of adatoms, geometrical and directional effects. The surface and cross‐section of the films were observed by scanning electron microscopy (SEM). OAD films develop a kind of smooth tiles of a roof structure, with no faceted crystallites. The columns of these films were tilted toward the direction of incident flux. The dependence of (111) texture tilt angle and column angle β on the incidence flux angle α is evaluated using four well‐known models. Transmission electron microscopy (TEM) study reveals a voided, intercolumnar structure with oblique growth toward the flux direction. The selected area diffraction pattern (SAED) pattern supports the pole figure observations. Measurements of the nanoindentation test were performed in order to discuss the change of mechanical properties as a function of incident flux angle.
Impact of substrate temperature and film thickness on the interfacial evolution during atomic layer deposition of HfO2 on InP
Authors: An Chee‐Hong , Byun Young‐Chul , Lee Myung Soo , Kim Hyoungsub 
Published: April 2012

AbstractThe effects of both the deposition temperature and the HfO2 film thickness on the interfacial layer (IL) evolution were studied when tetrakis(ethylmethylamino)hafnium and H2O based atomic layer deposition (ALD) was performed on InP substrates. While the self‐cleaning effect resulted in an IL‐free structure after formation of ∼2 nm thick HfO2 at 200 °C and 250 °C, substantial IL growth occurred at 300 °C, probably due to simultaneous InP oxidation. Following further growth to ∼8 nm at 300 °C, the IL was almost removed and, in particular, a significant In incorporation into the HfO2 film was observed, which was attributed to IL decomposition and subsequent out‐diffusion of the constituent elements. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Validation of a Model of Plastic Deformation of Niobium Microalloyed Steels in the Two‐Phase Temperature Region
Authors: Niżnik Barbara , Kuziak Roman , Pietrzyk Maciej 
Published: April 2012

AbstractThis article describes a thermo‐mechanical‐microstructural model for deformation of niobium microalloyed steel in the two‐phase range of temperatures. Results of physical and numerical modeling are presented. The physical simulation experiments include plastometric and dilatometric tests, as well as industrial rolling trial. Plastometric tests were performed to describe the flow stress for the wide range of temperatures, including ferritic, two‐phase, and austenitic states. Two‐stage deformation tests were performed to identify the microstructure evolution model. Dilatometric tests were used to identify the model of phase transformation. A model of the kinetics of the precipitation was adapted from the literature. The coefficients in all the models were identified using inverse analysis. Developed models were implemented in the finite element code. In order to improve the accuracy of the flow stress predictions in the two‐phase phase temperature range, internal variable dislocation density model was included, as well. The proposed combination of models correctly predicted microstructure changes and mechanical properties in the two‐phase range, during the transformations of the thermo‐mechanical treatment. Industrial trials were performed for the final validation of the models.
Martensitic Transformation Behavior of B‐Bearing Steel During Isothermal Deformation
Authors: Salari Sina , Saeed‐Akbari Alireza , Naderi Malek , Bleck Wolfgang 
Published: April 2012

AbstractThe purpose of the present research is to study the martensitic transformation in 22MnB5 steel under thermomechanical conditions by means of dilatation data. To reach this aim, the effects of deformation temperature and strain rate on the martensitic dilatation as well as martensite start temperature (Ms) were investigated. Thermomechanical treatments were performed in a deformation dilatometer including the isothermal deformation of samples in the temperature range of 550–900°C up to the final strain of 0.5 in three strain rates of 0.1, 1, and 10 s−1. Finally, deformation temperatures were divided into two regimes of lower and higher than 800°C. In the former, strain‐induced phase transformations, while in the latter, occurrence of dynamic recovery against mechanical stabilization of austenite influenced martensitic transformation.
Concise Review: Stem Cells in the Corneal Stroma
Authors: Pinnamaneni Niveditha , Funderburgh James L. 
Published: April 2012

Abstract
The cornea is a tough transparent tissue admitting and focusing light in the eye. More than 90% of the cornea is stroma, a highly organized, transparent connective tissue maintained by keratocytes, quiescent mesenchymal cells of neural crest origin. A small population of cells in the mammalian stroma displays properties of mesenchymal stem cells, including clonal growth, multipotent differentiation, and expression of an array of stem cell-specific markers. Unlike keratocytes, the corneal stromal stem cells (CSSCs) undergo extensive expansion in vitro without loss of the ability to adopt a keratocyte phenotype. Several lines of evidence suggest CSSCs to be of neural crest lineage and not from bone marrow. CSSCs are localized in the anterior peripheral (limbal) stroma near to stem cells of the corneal epithelium. CSSCs may function to support potency of the epithelial stem cells in their unique limbal niche. On the other hand, little information is available documenting a role for CSSCs in vivo in stromal wound healing or regeneration. In vitro CSSCs reproduce the highly organized connective tissue of the stroma, demonstrating a potential use of these cells in tissue bioengineering. Direct introduction of CSSCs into the corneal stroma generated transparent tissue in a mouse model of corneal opacity. Human CSSCs injected into mice corneas did not elicit immune rejection over an extended period of time. The CSSCs therefore appear offer an opportunity to develop cell- and tissue-based therapies for irreversible corneal blindness, conditions affecting more than 10 million individuals worldwide.
Disclosure of potential conflicts of interest is found at the end of this article.
Xenotransplanted Embryonic Kidney Provides a Niche for Endogenous Mesenchymal Stem Cell Differentiation into Erythropoietin-Producing Tissue
Authors: Matsumoto Kei , Yokoo Takashi , Matsunari Hitomi , Iwai Satomi , Yokote Shinya , Teratani Takumi , Gheisari Yousof , Tsuji Osahiko , Okano Hideyuki , Utsunomiya Yasunori , Hosoya Tatsuo , Okano Hirotaka James , Nagashima Hiroshi , Kobayashi Eiji 
Published: April 2012

AbstractRecent findings have demonstrated that stem cells can differentiate into mature tissue when supplied with a niche containing factors identical to those in the normal developmental program. A niche for the development of an organ can be provided by xenotransplantation of a similar developing organ. However, this process has many technical, safety, and ethical concerns. Here, we established xenotransplantation models that control endogenous mesenchymal stem cell (MSC) differentiation into mature erythropoietin (EPO)-producing tissue in a niche provided by a developing xenometanephros. Transplantation of rat metanephroi into mouse omentum, and similarly pig metanephroi into cat omentum, led to the recruitment of host cells and EPO production. EPO-expressing cells were not differentiated from integrating vessels because they did not coexpress endothelial markers (Tie-2 and VE-cadherin). Instead, EPO-expressing cells were shown to be derived from circulating host cells, as shown by enhanced green fluorescent protein (EGFP) expression in the grown transplants of chimeric mice bearing bone marrow from a transgenic mouse expressing EGFP under the control of the EPO promoter. These results suggest that donor cell recruitment and differentiation in a xenotransplanted developing organ may be consistent between species. The cells responsible for EPO expression were identified as MSCs by injecting human bone marrow-derived MSCs and endothelial progenitor cells into NOD/SCID mice. Furthermore, using metanephroi from transgenic ER-E2F1 suicide-inducible mice, the xenotissue component could be eliminated, leaving autologous EPO-producing tissue. Our findings may alleviate adverse effects due to long-lasting immunosuppression and help mitigate ethical concerns.Disclosure of potential conflicts of interest is found at the end of this article.
Covering and Uncovering Equivalent Mutants
Authors: Schuler David , Zeller Andreas 
Published: April 2012

SUMMARYMutation testing measures the adequacy of a test suite by seeding artificial defects (mutations) into a program. If a test suite fails to detect a mutation, it may also fail to detect real defects—and hence should be improved. However, there are also mutations that keep the program semantics unchanged and thus cannot be detected by any test suite. Such equivalent mutants must be weeded out manually, which is a tedious task. In this paper, we examine whether changes in coverage can be used to detect non‐equivalent mutants: If a mutant changes the coverage of a run, it is more likely to be non‐equivalent. In a sample of 140 manually classified mutations of seven Java programs with 5000 to 100 000 lines of code, we found that (i) the problem is serious and widespread—about 45% of all undetected mutants turned out to be equivalent; (ii) manual classification takes time—about 15 min per mutation; (iii) coverage is a simple, efficient and effective means to identify equivalent mutants—with a classification precision of 75% and a recall of 56%; and (iv) coverage as an equivalence detector is superior to the state of the art, in particular violations of dynamic invariants. Our detectors have been released as part of the open‐source JAVALANCHE framework; the data set is publicly available for replication and extension of experiments. Copyright © 2012 John Wiley & Sons, Ltd.
Taking Full Advantage of Children's Literature
Authors: Serafini Frank 
Published: April 2012

AbstractTeachers need a deeper understanding of the texts being discussed, in particular the various textual and visual aspects of picturebooks themselves, including the images, written text and design elements, to support how readers made sense of these texts.As teachers become familiar with aspects of literary criticism, art history, visual grammar, picturebook design, peritextual devices and narrative theories, they are better positioned to take full advantage of the discussions that occur in their classrooms.
Genetic controls and cellular behaviors in branching morphogenesis of the renal collecting system
Authors: Costantini Frank 
Published: April 2012

AbstractThe mammalian kidney, which at maturity contains thousands of nephrons joined to a highly branched collecting duct (CD) system, is an important model system for studying the development of a complex organ. Furthermore, congenital anomalies of the kidney and urinary tract, often resulting from defects in ureteric bud branching morphogenesis, are relatively common human birth defects. Kidney development is initiated by interactions between the nephric duct and the metanephric mesenchyme, leading to the outgrowth and repeated branching of the ureteric bud epithelium, which gives rise to the entire renal CD system. Meanwhile, signals from the ureteric bud induce the mesenchyme cells to form the nephron epithelia. This review focuses on development of the CD system, with emphasis on the mouse as an experimental system. The major topics covered include the origin and development of the nephric duct, formation of the ureteric bud, branching morphogenesis of the ureteric bud, and elongation of the CDs. The signals, receptors, transcription factors, and other regulatory molecules implicated in these processes are discussed. In addition, our current knowledge of cellular behaviors that are controlled by these genes and underlie development of the collecting system is reviewed. WIREs Dev Biol 2012. doi: 10.1002/wdev.52For further resources related to this article, please visit the WIREs website.