bluuebunny/crossref_metadata_2025 huggingface dataset:
Propaganda as Leftist Culture:
Authors: Ye Luofu
Published: March 2015

This article aims to discuss Hong Kong's leftist culture during the Cultural Revolution. By reviewing the history of leftist culture in Hong Kong and analyzing Hong Kong's leftist publications before and during the Cultural Revolution, this article argues that during Hong Kong's involvement in the Cultural Revolution, the leftist culture in Hong Kong was degraded to propaganda and lost its status as major ideology. On the other hand, the colonial government was determined to improve the economic and education level after 1967 social unrest, and modern Hong Kong's identity emerged as a combination of commercial and consumer culture and traditional Chinese cultural heritage. Hong Kong's Maoist experience was a failure but it had a positive influence on social development.
From Taboo to Open Discussion:
Authors: Lanlan Du
Published: March 2015

As an axis of identity, sexuality is a product of social relations framed by different networks of power. It is closely related to the social, political, and cultural milieu of a specific society. In China, discussions of sex during the Cultural Revolutionary period was remarkably limited, which is distinctly different from those of the post-Maoist era. Whereas the Maoist state had an aggressive regulation and policing of gender and sexuality, in post-Maoist culture erotic desire becomes a way of liberation. This article aims to take Azalea Mountain, one of the eight model operas in the Maoist era, and Red Azalea, Anchee Min's 1994 memoir about Cultural Revolution, as a case study to show that literary discourses of sexuality during the Maoist Cultural Revolution and the subsequent post-Mao era undergo a shift from a total absence to open discussion.
The Construction of the Image/Myth of a Martyr in the Cultural Revolution:
Authors: Wang Xian
Published: March 2015

Jin Jingmai's novel The Song of Ouyang Hai was published in 1965 and became extremely popular in 1966 right before the launch of the Cultural Revolution. It can be regarded as a prelude to Cultural Revolution literature. The novel epitomizes the transition from the politically inclined “seventeen-year literature” (1949–66) to the highly politicalized “Cultural Revolution literature” (1966–76). It is also the perfect embodiment of the creation of the myth of a socialist martyr. In this article, I attempt to examine the features of socialist martyrs and decode the construction of the myth of such martyrs by exploring motifs such as diaries, letters, and the performative bodies in The Song of Ouyang Hai as well as related works and posters that feature revolutionary and socialist martyrs from the 1960s. The article also examines how the constant revisions of the novel driven by the political power struggles during and after the Cultural Revolution complicate and adumbrate the myth of the socialist martyr.
El formador de profesores de matemática: un análisis de las percepciones de sus prácticas instruccionales desde la “tensión” estudiante-formador
Authors: Rojas Francisco , Deulofeu Jordi
Published: March 2015

El formador de profesores, como aquel que apoya al profesor en el desarrollo y la mejora de la enseñanza de las matemáticas, tiene una fuerte incidencia en la construcción del conocimiento inicial para la enseñanza en sus estudiantes. Considerando el contexto de un master de formación de profesorado, analizamos las percepciones de estudiantes y formadores sobre la actividad instruccional experimentada en cursos de tipo didáctico. Las opiniones han sido recogidas por medio de dos focus group, construidos de forma secuencial e inclusiva. Un aspecto que resulta clave para los estudiantes en tanto una característica fundamental de las prácticas instruccionales de sus formadores, dice relación con la coherencia entre las prácticas instruccionales de éstos y la racionalidad formativa que se busca intencionar en la gestión de las actividades didáctico-matemáticas realizadas.
Objetos matemáticos, representaciones semióticas y sentidos
Authors: Rojas Garzon Pedro Javier
Published: March 2015

En este documento presento algunos resultados del estudio realizado sobre un fenómeno relacionado con la articulación de los sentidos asignados por estudiantes a diferentes representaciones de un objeto matemático, obtenidas mediante transformaciones semióticas de tratamiento. Describo y analizo algunos procesos de asignación de sentidos logrados por los estudiantes de grados 9º y 11º de educación básica y media (Colombia), en relación con tareas específicas en las que requieren realizar dichos tratamientos entre representaciones, y reporto algunas dificultades asociadas. En este estudio incluyo aspectos relacionados con la actividad matemática, la comunicación sobre objetos matemáticos emergentes y la construcción cognitiva de los objetos matemáticos.
La actitud hacia el bienestar animal en el ámbito educativo
Authors: Mazas Gil Beatriz
Published: March 2015

La investigación que se presenta en esta tesis doctoral aborda un tema delicado pero subyacente en la sociedad: El bienestar de los animales. El concepto clásico de bienestar animal se limitaba a que los animales estuviesen físicamente sanos, bien alimentados y libres de agresiones físicas del ambiente, que recibieron la consideración de «las tres libertades». La nueva concepción de bienestar animal se basa en la capacidad de los animales para adaptarse con éxito a un ambiente dado y desarrollar todo su potencial fisiológico y etológico. Por tanto, a las tres primeras libertades de los animales ampliamente aceptadas se agregaron dos nuevas, las que se enuncian como libertad para expresar los comportamientos naturales de la especie, y que los animales estén libres de miedo o estrés.
El desarrollo del currículum desde la perspectiva del profesorado de educación primaria. La nutrición humana
Authors: Rivadulla López Juan Carlos
Published: March 2015

El objetivo de esta investigación es ofrecer una revisión del pensamiento del profesorado en ejercicio y en formación de educación primaria sobre la enseñanza de la nutrición humana. Concretamente, se trata de averiguar a qué aspectos le dan más importancia y en qué medida promueven la adquisición de una idea global de nutrición. También se establecen comparaciones entre lo que valora como importante cada colectivo respecto a la enseñanza de la nutrición humana, y los contenidos que enseñan/enseñarían y los que evalúan/evaluarían.
Astronomía, Matemáticas y su enseñanza en la obra de Fray Martín Sarmiento (1695-1772). Aplicaciones didácticas de la historia de las ciencias y las técnicas
Authors: Pérez Rodríguez Uxío
Published: March 2015

En esta investigación se estudian los escritos astronómicos y matemáticos de Fray Martín Sarmiento y se analizan sus propuestas sobre la educación científica de la juventud. También se reflexiona sobre la utilización didáctica de la Historia de las Ciencias y las Técnicas (HCT).
Soil Moisture Retrieval from MODIS and AMSRE Satellite Data A Case Study of Sindh Province, Pakistan
Authors: Syed Shahid Ali  , Muhammad Usman Khan  , Sayed Sanaullah Shah
Published: March 2015

Sindh province has diverse agro-climatological regions ranging from irrigated agricultural belt in the middle and desert to the east and bare hilly ranges on the west. Climate of the province is semi-arid with low annual precipitation of around 200mm. Agriculture and agribusiness is the main source of livelihood for majority in the province. Soil moisture study is an important parameter in agriculture, hydrology and hydrometeorology for studies related to sustainable development of agriculture and agribusiness in the province. In agriculture, soil moisture is used to study evapotranspiration, droughts, irrigation scheduling, and crop yield forecasting. It is also important for the environmental studies like subsequent precipitation patterns, temperature change and water quality. Soil moisture plays an important role in hydrology e.g., flood control, soil erosion and slope failure, reservoir management, geotechnical engineering and runoff generation. Due to synoptic coverage and high temporal resolution satellite remote sensing is ideal for instantaneous measurement of soil moisture content and its spatial and temporal behavior. In this study soil moisture at province level has been mapped through Advanced Microwave Scanning Radiometer (AMSR-E) and Moderate Resolution Imaging Spector Radiometer (MODIS) for the years 2007 and 2010. As 2007 was as normal year while 2010 was a wet year due to heavy rainfall and flood in the province, both the years have been selected to study soil moisture anomalies in normal and wet seasons. The results of MODIS derived soil moisture is in moderate agreement with AMSR-E soil moisture product proving the effectiveness of high resolution products in optical range.
Manufacturing in Sindh: Growth and Spatial Distribution
Authors: Muhammad Jawed Iqbal  , Syed Shahid Ali
Published: March 2015

Manufacturing is significantly important in Sindh. It is a major contributor of the GDP along with the agriculture sector. Industrial development of Sindh occurred after the emergence of Pakistan and manufacturing gained considerable size in the recent years as a major economic activity in the province. The paper focuses on chief aspects i.e. growth and concentration pattern. The trends and rate of growth have been analyzed over a period of thirty years beginning 1975-76. The spatial pattern is shown by the technique of location quotient which measures the extent of concentration of manufacturing in the districts of Sindh. Three districts i.e. Karachi, Dadu and Hyderabad emerge as major industrial concentrations.
Auxin regulates SNARE-dependent vacuolar morphology restricting cell size
Authors: Löfke Christian , Dünser Kai , Scheuring David , Kleine-Vehn Jürgen
Published: March 2015

The control of cellular growth is central to multicellular patterning. In plants, the encapsulating cell wall literally binds neighbouring cells to each other and limits cellular sliding/migration. In contrast to its developmental importance, growth regulation is poorly understood in plants. Here, we reveal that the phytohormone auxin impacts on the shape of the biggest plant organelle, the vacuole. TIR1/AFBs-dependent auxin signalling posttranslationally controls the protein abundance of vacuolar SNARE components. Genetic and pharmacological interference with the auxin effect on vacuolar SNAREs interrelates with auxin-resistant vacuolar morphogenesis and cell size regulation. Vacuolar SNARE VTI11 is strictly required for auxin-reliant vacuolar morphogenesis and loss of function renders cells largely insensitive to auxin-dependent growth inhibition. Our data suggests that the adaptation of SNARE-dependent vacuolar morphogenesis allows auxin to limit cellular expansion, contributing to root organ growth rates.
Teaching Early Reading Skills to Children with Intellectual and Developmental Disabilities Using Computer-Delivered Instruction: A Pilot Study
Authors: Tyler Emily J. , Hughes John C. , Wilson Meadhbh M. , Beverley Michael , Hastings Richard P. , Williams Bethan M.
Published: March 2015

Many children with Intellectual and Developmental Disabilities (IDD) have considerable difficulty learning basic reading skills. Increasing evidence suggests individuals with IDD may benefit from instruction incorporating components of reading found to be effective for typically developing children. However, little research into reading instruction for children with IDD has incorporated these components. There is evidence for the efficacy of Headsprout® Early Reading program for typically developing children, and emerging evidence suggesting that children with autism can benefit from the program. The current study investigated the accessibility of Headsprout® Early Reading for children with IDD, and whether there were any measurable effects of the program on important early reading and language skills. Six children aged between 7 and 14 years with mild to moderate IDD completed the program, and all made measurable improvements across reading measures, demonstrating children with mild to moderate IDD can access (i.e., progress through and benefit from) the program.
Pressurized magma reservoir within the east rift zone of Kīlauea Volcano, Hawai‘i: Evidence for relaxed stress changes from the 1975 Kalapana earthquake
Authors: Baker Scott , Amelung Falk
Published: March 2015

We use 2000–2012 InSAR data from multiple satellites to investigate magma storage in Kīlauea's east rift zone (ERZ). The study period includes a surge in magma supply rate and intrusion‐eruptions in 2007 and 2011. The Kupaianaha area inflated by ~5 cm prior to the 2007 intrusion and the Nāpau Crater area by ~10 cm following the 2011 intrusion. For the Nāpau Crater area, elastic modeling suggests an inflation source at 5 ± 2 km depth or more below sea level. The reservoir is located in the deeper section of the rift zone for which secular magma intrusion was inferred for the period following the 1975 Mw7.7 décollement earthquake. Reservoir pressurization suggests that in this section of the ERZ, extensional stress changes due to the earthquake have largely been compensated for and that this section is approaching its pre‐1975 state. Reservoir pressurization also puts the molten core model into question for this section of Kīlauea's rift zone.
Perturbation Methods
Authors: Murdock James
Published: March 2015

When a solvable mathematical problem is changed slightly, or perturbed, it may become unsolvable (in closed form). Perturbation theory enables an approximate solution to be constructed; in the simplest cases, this is done by adding successive correction terms to the solution of the unperturbed problem. The roots of the method, which lie in celestial mechanics, fluid flow, and quantum mechanics, are briefly described. The notions of perturbation series, uniform asymptotic validity, and regular and singular problems are defined. In the area of nonlinear oscillations, the most important methods are the Lindstedt method (or method of strained coordinates), the method of multiple scales, and the method of averaging; these are described and compared. Special results for the averaging of multifrequency Hamiltonian systems, including the Kolmogorov–Arnol'd–Moser theorem and the Nekhoroshev theorem, are briefly described. In dynamical systems, the Melnikov integral describes the perturbation of stable and unstable manifolds. Differential equations in which a small parameter multiplies the highest derivative lead to solutions having initial or boundary layers. The multiple‐scale method and methods of matched asymptotic expansions for these problems are described. The WKB method can also be used in certain cases. The matching method for partial differential equations is illustrated by the boundary layer problem for fluid flow. The newer RG method can sometimes replace these older methods; we compare three versions of the RG method via simple examples. Finally, several approaches to the problem of finding the eigenvalues (spectra) of perturbed matrices and linear transformations are described.
Special Functions
Authors: Athorne Chris
Published: March 2015

The article conbtains sections titled:

Introduction

Discrete Symmetry

Symmetries

Coxeter Groups

Symmetric Functions

Invariants of Coxeter Groups

Fuchsian Equations

Continuous Symmetry

Lie Groups and Lie Algebras

Representations

The Laplace Operator

Spherical Harmonics

Separation of Variables

Bessel Functions

Addition Laws

The Hypergeometric Equation

Orthogonality

Orthogonal Polynomials

Factorization

The Bessel Equation

Hermite

Legendre

“Factorization” of PDEs

Dunkl Operators

Special Functions Without Symmetry

Airy Functions

Liouville Theory

Differential Galois Theory

Nonlinear Special Functions

Weierstraß Elliptic Functions

Jacobian Elliptic Functions

Theta Functions

Painlevé Transcendents

Discrete Special Functions

– Theory

Quantum Groups

Difference Operators

‐Hermite Polynomials

Discrete Painlevé Equations
Graph and Network Theory
Authors: Estrada Ernesto
Published: March 2015

This Chapter introduces the basic concepts of graphs and networks and their applications in physics. It explains the connections of graph theory with condensed matter and statistical physics by studying the tight‐binding, Hubbard and Potts models. The use of graphs for solving problems in quantum field theory is illustrated by studying the Feynman graphs. Other physical scenarios in which graph theory is presented here are the study of electrical networks and vibrational systems. The Chapter also introduces the concepts of random graphs and complex networks. In the last topic, the most relevant structural concepts for complex networks are studied and a few dynamical processes such as consensus, synchronization and epidemics spreading, are discussed.
Algebraic Topology
Authors: Robins Vanessa
Published: March 2015

The article contains sections titled:

Introduction

Homotopy Theory

Homotopy of Paths

The Fundamental Group

Homotopy of Spaces

Examples

Covering Spaces

Extensions and Applications

Homology

Simplicial Complexes

Simplicial Homology Groups

Basic Properties of Homology Groups

Homological Algebra

Other Homology Theories

Cohomology

De Rham Cohomology

Morse Theory

Basic Results

Extensions and Applications

Forman's Discrete Morse Theory

Computational Topology

The Fundamental Group of a Simplicial Complex

Smith Normal form for Homology

Persistent Homology

Cell Complexes from Data

Further Reading
Differentiable Manifolds
Authors: Epstein Marcelo
Published: March 2015

Differentiable manifolds are spaces on which differentiable functions can be defined. They are, therefore, a generalization of the ordinary ‐dimensional space ; hence their usefulness and ubiquity in Physics, particularly in field theories. A rigorous definition of (finite‐dimensional) differentiable manifolds is followed by a treatment of vector and tensor fields, differential forms, and the Lie derivative. This chapter serves as an introduction to the companion article on Topics in Differential Geometry.
Dynamical Systems
Authors: Barton David A.W.
Published: March 2015

The article contains sections titled:

Introduction

Definition of a Dynamical System

Invariant Sets

Equilibria

Definition and Calculation

Stability

Linearization

Lyapunov Functions

Topological Equivalence

Manifolds

Local Bifurcations

Saddle‐Node Bifurcation

Hopf Bifurcation

Pitchfork Bifurcation

Center Manifolds

Limit Cycles

Definition and Calculation

Linearization

Topological Equivalence

Manifolds

Local Bifurcations

Period‐Doubling Bifurcation

Numerical Continuation

Natural Parameter Continuation

Pseudo‐Arc‐Length Continuation

Continuation of Bifurcations
Calculus of Variations
Authors: Roubíček Tomáš
Published: March 2015

Basic general concepts and results from modern calculus of variations are presented both on an abstract level, based on nonlinear smooth, convex, or nonsmooth analysis on linear (namely Banach) spaces, and then on a concrete level of multidimensional variational problems on function (namely Sobolev) spaces leading to 2nd‐ or 4th‐order elliptic equations or systems. Beside static problems, also evolution problems are addressed, both for various variational principles and for recursive variational problems occuring after time discretisation. Concrete illustrative examples concern heat‐transfer problems, elasticity both at large and at small strains, micromagnetism, etc.
Functionalized Polyelectrolytes Assembling on Nano‐BioFETs for Biosensing Applications
Authors: Duan Xuexin , Mu Luye , Sawtelle Sonya D. , Rajan Nitin K. , Han Ziyu , Wang Yanyan , Qu Hemi , Reed Mark A.
Published: March 2015

A new surface functionalization scheme for nano‐Bio field effect transistors (FETs) using biocompatible polyelectrolyte thin films (PET) is developed. PET assemblies on Si nanowires (Si‐NWs) are driven by electrostatic interactions between the positively charged polymer backbone and negatively charged Si/SiO2 surface. Such assemblies can be directly coated from PET aqueous solutions and result in a uniform nanoscale thin film, which is more stable compared to the conventional amine silanization. Short oligo‐ethylene glycol chains are grafted on the PETs to prevent nonspecific protein binding. Moreover, the reactive groups of the polymer chains can be further functionalized to other chemical groups in specific stoichiometry for biomolecules detection. Therefore, it opens a new strategy to precisely control the functional group densities on various biosensor surfaces at the molecular level. In addition, such assemblies of the polymers together with the bound analytes can be removed with the pH stimulation resulting in regeneration of a bare sensor surface without compromising the integrity and performance of the Si‐NWs. Thus, it is believed that the developed PET coating and sensing systems on Si‐NW FETs represent a versatile, promising approach for regenerative biosensors which can be applied to other biosensors and will benefit real device applications, enhancing sensor lifetime, reliability, and repeatability.
Cobalt(II)‐Catalyzed Electrophilic Alkynylation of 1,3‐Dicarbonyl Compounds To Form Polysubstituted Furans via π–π Activation
Authors: Roslan Irwan Iskandar , Sun Jiulong , Chuah Gaik‐Khuan , Jaenicke Stephan
Published: March 2015

Polysubstituted furans were obtained with excellent yields via the electrophilic alkynylation of 1,3‐dicarbonyl compoundsws with phenyl‐ or ester‐substituted brominated alkynes. The reaction is catalyzed by the inexpensive and readily available catalyst, cobalt(II) chloride, and has a wide substrate scope. The C(sp)C(sp3) coupling occurs under mild conditions with short reaction times and does not require an inert atmosphere or ligands. It is proposed that the reaction proceeds through a chelation complex of cobalt(II) with the deprotonated 1,3‐dicarbonyl compound.

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Gas–Liquid Segmented Flow Microfluidics for Screening Copper/TEMPO‐Catalyzed Aerobic Oxidation of Primary Alcohols
Authors: Vanoye Laurent , Pablos Mertxe , de Bellefon Claude , Favre‐Réguillon Alain
Published: March 2015

Aerobic oxidation using a combination of copper salts and 2,2,6,6‐tetramethylpiperidine N‐oxyl (TEMPO) represent useful tools for organic synthesis and several closely related catalyst systems have been reported. To gain further insights, these catalytic systems were evaluated in a gas–liquid segmented flow device. The improvement of oxygen mass transfer has a significant influence on the turnover‐limiting step. Hence, an improved catalytic system using copper(II) as copper source was implemented in a microreactor for the safe and efficient oxidation of primary alcohol.

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Optimal planning for the reuse of municipal solid waste considering economic, environmental, and safety objectives
Authors: Santibañez‐Aguilar José Ezequiel , Martinez‐Gomez Juan , Ponce‐Ortega José María , Nápoles‐Rivera Fabricio , Serna‐González Medardo , González‐Campos Janett Betzabe , El‐Halwagi Mahmoud M.
Published: March 2015

A mathematical programming model is presente for the optimal planning of the reuse of municipal solid waste (MSW) to maximize the economic benefit while simultaneously considering sustainability and safety criteria. The proposed methodology considers several phases of the supply chain including waste separation, distribution to processing facilities, processing to obtain useful products, and distribution of products to consumers. Additionally, the safety criteria are based on the potential fatalities associated with waste management. The proposed optimization model is formulated as a multiobjective optimization problem, which considers three different objectives including the maximization of the net annual profit, the maximization of the amount of reused MSW, and the minimization of the social risk associated with the supply chain. The proposed model is applied to a case study in the central‐west region of Mexico. The results show the tradeoff between the social risk and the economic and environmental criteria. © 2015 American Institute of Chemical Engineers AIChE J, 61: 1881–1899, 2015
One‐Step Synthesis of a [20]Silafullerane with an Endohedral Chloride Ion
Authors: Tillmann Jan , Wender Josef Heinrich , Bahr Ute , Bolte Michael , Lerner Hans‐Wolfram , Holthausen Max C. , Wagner Matthias
Published: March 2015

Silicon analogues of the most prominent carbon nanostructures, namely, hollow spheroidals such as C60 and the fullerene family, have been unknown to date. Herein we show that discrete Si20 dodecahedra, stabilized by an endohedral guest and valence saturation, are accessible in preparative yields through a chloride‐induced disproportionation reaction of hexachlorodisilane in the presence of tri(n‐butyl)amine. X‐ray crystallography revealed that each silicon dodecahedron contains an endohedral chloride ion that imparts a net negative charge. Eight chloro substituents and twelve trichlorosilyl groups are attached to the surface of each cluster in a strictly regioregular arrangement, a thermodynamically preferred substitution pattern according to quantum‐chemical assessment. Our results demonstrate that the wet‐chemical self‐assembly of a complex, monodisperse Si nanostructure is possible under mild conditions starting from simple Si2 building blocks.
Preparation and properties of functionalized graphene/waterborne polyurethane composites with highly hydrophobic
Authors: Luo Xiaomin , Zhang Peng , Ren Jing , Liu Rui , Feng Jianyan , Ge Binghui
Published: March 2015

The long‐chain functionalized graphene nanoplatelets (FGN) were functionalized by isophorone diisocyanate and then octadecylamine, the graphene functionalized/waterborne polyurethane (WPU) composites were prepared by solution mixture. The results showed that the FGN achieved good dispersion with exfoliated and intercalated nanostructure and strong interfacial adhesion with WPU, which made the nano–composites have a significant enhancement of thermal stability and mechanical properties at low FGN loadings. With 1.5% of FGN added, the tensile strength of the composites reached the maximum of 17 MPa, which improved by 41.6%, the water absorption of the composites is only 6.7%. With the incorporation of 2 wt % FGN, and the static contact angle of the composites reached to about 120°, showing the high hydrophobicity. At the same time, the volume resistivity of the composites was changed from 2.34 × 1012 Ω·cm to 3.77 × 109 Ω·cm. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42005.
Dynamic swelling behavior of interpenetrating polymer networks in response to temperature and pH
Authors: Slaughter Brandon V. , Blanchard Aaron T. , Maass Katie F. , Peppas Nicholas A.
Published: March 2015

Temperature responsive hydrogels based on ionic polymers exhibit swelling transitions in aqueous solutions as a function of shifting pH and ionic strength, in addition to temperature. Applying these hydrogels to useful applications, particularly for biomedical purposes such as drug delivery and regenerative medicine, is critically dependent on understanding the hydrogel solution responses as a function of all three parameters together. In this work, interpenetrating polymer network (IPN) hydrogels of polyacrylamide and poly(acrylic acid) were formulated over a broad range of synthesis variables using a fractional factorial design, and were examined for equilibrium temperature responsive swelling in a variety of solution conditions. Due to the acidic nature of these IPN hydrogels, usable upper critical solution temperature (UCST) responses for this system occur in mildly acidic environments. Responses were characterized in terms of maximum equilibrium swelling and temperature‐triggered swelling using turbidity and gravimetric measurements. Additionally, synthesis parameters critical to achieving optimal overall swelling, temperature‐triggered swelling, and sigmoidal temperature transitions for this IPN system were analyzed based on the fractional factorial design used to formulate these hydrogels. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42076.
Releasing property from surface polyion complex gel
Authors: Ajiro Hiroharu , Takemoto Yukie , Takemura Kazuya , Asoh Taka‐aki , Akashi Mitsuru
Published: March 2015

Surface polyion complex (sPIC) gels were prepared with a nonionic hydrogel interior core, composed of poly(N‐vinylformamide and poly(N‐vinylacetamide), and a chemically bounded polyion complex layer on the outer surface, composed of poly(vinylamine) and poly(acrylic acid). The gels were investigated as controlled drug release models based on electrostatic interactions depending on pH. Methylene blue and allura red were employed as cationic and anionic drug models, respectively, and resulted in the selective adsorption depending on pH conditions. Monovalent and multivalent anionic drug models, allura red and 1,3,6‐naphthalenetrisulfonate were observed for their releasing behavior from the sPIC gel. The results indicated that the multivalent anionic drug effectively controlled release depending on pH conditions. We further investigated sPIC gels regarding their ability to control the release of ionic molecules as a function of pH‐driven changes in electrostatic interactions. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42081.
Dynamic rheological behavior of reactively compatibilized polypropylene/polyamide 6 blending melts
Authors: Liao Hua‐yong , Zheng Lu‐yao , Hu Yong‐bing , Zha Xian‐jun , Xu Xiang , Wen Yan‐wei , Tao Guo‐liang , Liu Chun‐lin
Published: March 2015

The dynamic rheological behavior is measured by small amplitude oscillatory shear on rotational rheometer for polypropylene/polyamide 6 (PP/PA6) blends compatibilized by a polypropylene grafted maleic anhydride (PP‐g‐MAH). Scanning electron microscope (SEM) results show that the PP/PP‐g‐MAH/PA6 (=100/6/40wt) is sea‐island structure, the PP/PP‐g‐MAH/PA6 (=100/6/60wt) blend is semi‐cocontinuous. Coarse PA6 zones can be observed when the weight ratio is 100/6/80. At low frequency the complex viscosity, dynamic modulus of the PP/PP‐g‐MAH/PA6 (PP/PP‐g‐MAH = 100/6wt) blends first increase then drop with the increase of PA6 weight content in the range of 0–100, the maximum value arrives at the weight content of 60. The Cole–Cole plots as well as the weighted relaxation spectra of the blends have a main arc and a tail when the weight ratio of PP/PP‐g‐MAH/PA6 is in the range of 100/6/20–100/6/60, but have different shapes when the weight ratio increases to 100/6/80 and 100/6/100. The possible reason is the weight ratio of 100/6/80 and 100/6/100 is close to the phase inversion point. In fitting the storage modulus data at low frequency, Palierne's model with two parameters interfacial tension and interfacial shear modulus is better than Bousmina's model. Palierne's model with only one parameter of interfacial tension can not fit the data well. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42091.
Degradation of photovoltaic backsheets: Comparison of the aging induced changes on module and component level
Authors: Knausz Marlene , Oreski Gernot , Eder Gabriele C. , Voronko Yuliya , Duscher Bernadette , Koch Thomas , Pinter Gerald , Berger Karl A.
Published: March 2015

In reliability testing of components for PV modules an always remaining question is about material (in)compatibilities and synergistic effects and thus, how results of singly tested materials correlate with materials aged within PV modules. Testing of single materials would simplify sample preparation, reduce costs and offer more testing options. Therefore the main objective of this study was to compare the aging behavior of single backsheets with that of backsheets incorporated within PV modules. Four different types of backsheets were chosen, all of them comprising of polyethylene terephthalate (PET) core layers, but differing outer protection layers. Test modules using identical components, varying only in the type of backsheet used were produced and damp heat aged (85°C/85% RH ≤2000 h). The results revealed no influence of the PV module lamination on the thermal characteristics of the polymeric backsheets. Even after DH aging, differences between single and module laminated backsheets were negligible. Degradation effects of PET could be detected for all aged sheets by thermal analysis and were confirmed by tensile tests and rheological measurements. Thus, it can be stated that testing of single PET based backsheets under DH aging conditions is a practicable way to investigate the applicability of a new backsheet. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42093.
RNAi KNOCKDOWN OF BmRab3 LED TO LARVA AND PUPA LETHALITY IN SILKWORM Bombyx mori L.
Authors: Singh Chabungbam Orville , Xin Hu‐hu , Chen Rui‐ting , Wang Mei‐xian , Liang Shuang , Lu Yan , Cai Zi‐zheng , Zhang Deng‐pan , Miao Yun‐gen
Published: March 2015

Rab3 GTPases are known to play key a role in vesicular trafficking, and express highest in brain and endocrine tissues. In mammals, Rab3 GTPases are paralogs unlike in insect. In this study, we cloned Rab3 from the silk gland tissue of silkworm Bombyx mori, and identified it as BmRab3. Our in silico analysis indicated that BmRab3 is an isoform with a theoretical isoelectric point and molecular weight of 5.52 and 24.3 kDa, respectively. Further, BmRab3 showed the C‐terminal hypervariability for GGT2 site but having two other putative guanine nucleotide exchange factor/GDP dissociation inhibitor interaction sites. Multiple alignment sequence indicated high similarities of BmRab3 with Rab3 isoforms of other species. The phylogeny tree showed BmRab3 clustered between the species of Tribolium castaneum and Aedes aegypti. Meanwhile, the expression analysis of BmRab3 showed the highest expression in middle silk glands (MSGs) than all other tissues in the third day of fifth‐instar larva. Simultaneously, we showed the differential expression of BmRab3 in the early instar larva development, followed by higher expression in male than female pupae. In vivo dsRNA interference of BmRab3 reduced the expression of BmRab3 by 75% compared to the control in the MSGs in the first day. But as the worm grew to the third day, the difference of BmRab3 between knockdown and control was only about 10%. The knockdown later witnessed underdevelopment of the larvae and pharate pupae lethality in the overall development of silkworm B. mori L.
Leading change: Curriculum reform in graduate education in the biomedical sciences
Authors: Dasgupta Shoumita , Symes Karen , Hyman Linda
Published: March 2015

The Division of Graduate Medical Sciences at the Boston University School of Medicine houses numerous dynamic graduate programs. Doctoral students began their studies with laboratory rotations and classroom training in a variety of fundamental disciplines. Importantly, with 15 unique pathways of admission to these doctoral programs, there were also 15 unique curricula. Departments and programs offered courses independently, and students participated in curricula that were overlapping combinations of these courses. This system created curricula that were not coordinated and that had redundant course content as well as content gaps. A partnership of key stakeholders began a curriculum reform process to completely restructure doctoral education at the Boston University School of Medicine. The key pedagogical goals, objectives, and elements designed into the new curriculum through this reform process created a curriculum designed to foster the interdisciplinary thinking that students are ultimately asked to utilize in their research endeavors. We implemented comprehensive student and peer evaluation of the new Foundations in Biomedical Sciences integrated curriculum to assess the new curriculum. Furthermore, we detail how this process served as a gateway toward creating a more fully integrated graduate experience, under the umbrella of the Program in Biomedical Sciences. © 2015 by The International Union of Biochemistry and Molecular Biology, 43(2):126–132, 2015.
Development and application of an analytical method for curdione quantification in pregnant sprague–dawley rats by LC‐MS/MS
Authors: Meng Xiang , Zhang Ting , Li Ying , Pan Qi , Jiang Juan , Luo Yongwei , Chong Liming , Yang Yang , Xu Sichong , Zhou Li , Sun Zuyue
Published: March 2015

The vaginal administration route suffers from relatively low absorption efficiency, which may hinder the identification of the toxicokinetics of curdione in pregnant women. A sensitive analytical method for determining the plasma concentration of curdione was developed and applied in the determination of curdione in pregnant Sprague–Dawley rats as a simulated model. Glimepiride was used as an internal standard and chromatographic separation was achieved on a Capcell Pak C18 MGIII column. A gradient elution profile with 0.5% formic acid (A)–0.5% formic acid–acetonitrile (B) was selected as mobile phase. The selected reaction monitoring mode was used for quantification based on the target fragment ions m/z 237.2 to m/z 135.1 for curdione and m/z 491.3 to m/z 352.1 for the glimepiride. The standard curve was linear over the range of 0.5–500 ng/mL for curdione in rat plasma and yielded a consistent peak pattern, even at the lower limit of quantitation of 0.5 ng/mL. The retention times of curdione and IS were 6.55 and 6.59 min, respectively. The mean recovery of curdione in rat plasma was 95.5–101.1%. The intra‐day and inter‐day precisions were between 2.35 and 9.08%. This LC‐MS/MS method provides a simple and sensitive means for determining the plasma concentration. Copyright © 2015 John Wiley & Sons, Ltd.
LTA/Poly(1‐trimethylsilyl‐1‐propyne) Mixed‐Matrix Membranes for High‐Temperature CO2/N2 Separation
Authors: Fernández‐Barquín Ana , Casado‐Coterillo Clara , Palomino Miguel , Valencia Susana , Irabien Angel
Published: March 2015

Mixed‐matrix membranes (MMM) consisting of poly(1‐trimethylsilyl‐1‐propyne) (PTMSP) as continuous matrix and small‐pore LTA‐framework zeolites with Si/Al ratios from 1 (commercial zeolite A) to ∞ (ITQ‐29) as dispersed phase were prepared by solution casting. The thermal stability of the MMM is as high as that of glassy PTMSP polymer, whose high permeability is maintained even at increasing temperature. The effect of the Si/Al ratio in the zeolite fillers on the membrane performance is observed by the increasing CO2/N2 permselectivity of low‐Si/Al ratio zeolite A‐based membranes, in comparison with pure silica ITQ‐29. The performance of the LTA‐type zeolite‐PTMSP MMM was adjusted to the modified Maxwell model by estimating the chain immobilization factor and the interphase thickness as a function of temperature, Si/Al ratio, and zeolite loading.
High‐Performance Electrocatalysts for Oxygen Reduction Based on Nitrogen‐Doped Porous Carbon from Hydrothermal Treatment of Glucose and Dicyandiamide
Authors: Liu Xiaojun , Li Ligui , Zhou Weijia , Zhou Yucheng , Niu Wenhan , Chen Shaowei
Published: March 2015

A synthetic method was developed for the preparation of N‐doped porous carbon through hydrothermal treatment at controlled temperatures by using glucose and dicyandiamide as precursors and ZnCl2 as an activation reagent. Nitrogen doping was quantitatively determined by using XPS measurements and identified in the forms of pyridinic, pyrrolic, graphitic, and pyridinic N+O−nitrogen atoms. Further structural analysis by using SEM, TEM, XRD, Raman, FTIR, and BET measurements showed that the N‐doped porous carbons exhibited a microcrystalline graphite structure and a high specific surface area up to 1000 m2 g−1. Electrochemical studies showed that the samples all exhibited a remarkable ORR catalytic activity in alkaline media, which was comparable to that of state‐of‐the‐art Pt/C catalysts, and the one prepared at 800 °C was found to be the best among the series with an onset potential of +0.96 V, almost complete reduction of oxygen to OH−, and superior methanol tolerance and cycling stability.
Highly Graphitic Clew‐Like Nanocarbons for Supercapacitors
Authors: Liu Tiantian , Liu Enhui , Ding Rui , Luo Zhenyu , Hu Tiantian , Li Zengpeng
Published: March 2015

Highly graphitic clew‐like nanocarbons (HGCNs) are synthesized through a simple hydrothermal method followed by impregnation and catalytic graphitization at 900 °C, in which sucrose and nickel acetate are employed as the carbon source and nickel catalyst precursor, respectively. Transmission electron microscopy images clearly demonstrate that HGCN is composed of interconnected and curled carbon nanowires with sizes ranging from 10 to 25 nm, and these nanowires twist around each other to form clew‐like nanostructures. HGCNs combine the features of high specific surface area (≈691 m2 g−1), hierarchical micro‐/mesoporous architecture and a highly graphitic structure. The electrochemical measurements show that HGCNs present a low equivalent series resistance (ESR) of 0.53 Ω and a specific capacitance of 248 F g−1 at 0.5 A g−1 with 85 % retention even at a high current density of 5 A g−1, demonstrating that HGCNs provide favorable prospects in electrode materials for supercapacitors.
Tandem Gold/Silver‐Catalyzed Cycloaddition/Hydroarylation of 7‐Aryl‐1,6‐enynes to Form 6,6‐Diarylbicyclo[3.2.0]heptanes
Authors: Robertson Bradley D. , Brooner Rachel E. M. , Widenhoefer Ross A.
Published: March 2015

Mixtures of [{PCy2(o‐biphenyl)}AuCl] and AgSbF6 catalyze the tandem cycloaddition/hydroarylation of 7‐aryl‐1,6‐enynes with electron‐rich arenes to form 6,6‐diarylbicyclo[3.2.0]heptanes in good yield under mild conditions. Experimental observations point to a mechanism involving gold‐catalyzed cycloaddition followed by silver‐catalyzed hydroarylation of a bicyclo[3.2.0]hept‐1(7)‐ene intermediate.
Numerical evaluation and improvement efficiency of radial flow moving‐bed reactors for catalytic pyrolysis of light hydrocarbons to low carbon olefins
Authors: Xiao Fang‐Zhi , Chen Houyang , Luo Zheng‐Hong
Published: March 2015

A three‐dimensional (3D) reactor model based on the Eulerian‐Eulerian approach was applied to describe the gas‐solid flow and heat transfer performance in a radial flow moving bed reactor (RFMBR). A six‐lumped kinetic model for the catalytic pyrolysis of C4 hydrocarbon was employed. The heat transfer characteristics and species concentration profiles were investigated in the reactor under various reaction conditions. Effects of operation parameters and reactor structures on the reactor performance were also evaluated and optimized numerically. Simulation results show that there exists a good heat transfer performance between gas and solid phases in the catalyst bed. The temperature profiles and the species yield distributions are different with respect to bed height positions. Moreover, the results indicate that product yield is more sensitive to the reaction temperature than to the dilution rate and the reaction residence time. For the Z‐type centripetal flow RFMBR, an annular tube with an inverted cone structure is helpful to improve the uniformity of flow distribution and increase low‐carbon olefins yields.
Effect of CO2 on catalytic hydrotreatment of gas‐oil
Authors: Bezergianni Stella , Dagonikou Vasiliki
Published: March 2015

The aim of this study is to investigate the effect of CO2 on catalytic hydrotreatement of gas‐oil to evaluate the potential of catalytic co‐ hydroprocessing of petroleum fractions with liquid biomass. A total of six experiments were conducted under low (330 °C), mild (345 °C) and severe (360 °C) operating conditions employing straight run gas‐oil as the petroleum fraction feedstock. During three of these experiments CO2 was artificially added to the reaction system to assess its impact on the associated catalytic reactions over a commercial CoMo/Al2O3 catalyst. The dedicated experiments revealed a suspending role of CO2 on hydro‐ desulfurization (HDS), hydro‐denitrogenation (HDN), and saturation reactions, which is attributed to the subsequent hydrogen partial pressure reduction of the reacting system caused by the competitive water gas‐shift and methane reforming reactions.
Single‐incision laparoscopic cholecystectomy
Authors: Castellanos Andres , Fazendin Jessica , Panait Lucian
Published: March 2015

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New therapies for hepatitis C: Latin American perspectives
Authors: Botero Rafael Claudino , Tagle Martin
Published: March 2015

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Access to new direct‐acting antiviral agents against HCV infection: A view from Spain
Authors: Tomé Santiago , Otero Esteban
Published: March 2015

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Accesibilidad a los nuevos agentes antivirales directos contra la infeccion por VHC. Un punto de vista desde España
Authors: Tome Santiago , Otero Esteban
Published: March 2015

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Genetic variants in noncoding PIWI‐interacting RNA and colorectal cancer risk
Authors: Chu Haiyan , Xia Liping , Qiu Xiaonan , Gu Dongying , Zhu Linjun , Jin Jing , Hui Gaoyun , Hua Qiuhan , Du Mulong , Tong Na , Chen Jinfei , Zhang Zhengdong , Wang Meilin
Published: March 2015

BACKGROUND

PIWI‐interacting RNAs (piRNAs), which are a novel type of identified small noncoding RNA (ncRNA), play a crucial role in germline development and carcinogenesis.

METHODS

By systematically screening all known piRNAs, the authors identified 7 common single nucleotide polymorphisms (SNPs) in 9 piRNAs. Associations between these selected SNPs and the risk of colorectal cancer (CRC) were detected in a case‐control study. A quantitative real‐time polymerase chain reaction assay was used to evaluate messenger RNA (mRNA) expression levels of piR‐015551 and of the long ncRNA (lncRNA) LNC00964‐3 in 88 pairs of tissue samples.

RESULTS

The assay revealed that reference SNP rs11776042 in piR‐015551 was significantly associated with a decreased risk of CRC in an additive model (P = .020). However, this protective effect was not significant after correction for multiple comparisons (test for the false discovery rate; P = .140). Furthermore, the authors observed that mRNA expression levels of LNC00964‐3 (an lncRNA that included the piR‐015551 sequence but not piR‐015551) were significantly lower in CRC tissues than in corresponding normal tissues (P = 1.5 × 10−5 for LNC00964‐3; P = .899 for piR‐015551). Correlation analysis revealed that piR‐015551 expression was positively correlated with expression levels of LNC00964‐3 (CRC tissues: r = 0.574, P = 5.13 × 10−9; normal tissues: r = 0.601, P = 5.76 × 10−10). Moreover, rs11776042 was not significantly correlated with mRNA expression levels of piR‐015551 or LNC00964‐3 (all P > .05).

CONCLUSIONS

The current findings reveal the possibility that piR‐015551 may be generated from LNC00964‐3, which may be involved in the development of CRC. Cancer 2015;121:2044–2052. © 2015 American Cancer Society.