bluuebunny/crossref_metadata_2025 huggingface dataset:
ChemInform Abstract: Lignin Depolymerisation Strategies: Towards Valuable Chemicals and Fuels
Authors: Xu Chunping , Arancon Rick Arneil D. , Labidi Jalel , Luque Rafael
Published: December 2014

Review: [50 refs.
Äußerer Wärmeübergangskoeffizient bei der Kondensation von Reinstoffen an einem horizontalen Rippenrohr. Determination of the Outer Condensation Heat Transfer Coefficient of Pure Fluids on a Horizontal Low‐Finned Tube
Authors: Reif Anna , Büchner Alexander , Rehfeldt Sebastian , Klein Harald
Published: December 2014

Für die Auslegung von Wärmeübertragern mit niedrig berippten Rohren fehlen aussagekräftige Referenzanwendungen in der öffentlichen Literatur. Hier wurde bei der Kondensation von iso‐Propanol, iso‐Oktan und n‐Pentan der äußere Wärmeübergangskoeffizient an horizontalen Glatt‐ und Rippenrohren aus Stahl experimentell bestimmt. Rippenrohre steigerten den äußeren Wärmeübergangskoeffizient um mindestens den Faktor 3. Theoretische Modelle, die für die Kondensation von Kältemitteln an Rippenrohren aus Kupfer entwickelt wurden, können bei den hier durchgeführten Messungen nur bedingt angewendet werden.
Structure and Thermodynamics of Mg:Phosphate Interactions in Water: A Simulation Study
Authors: Kumar Manjeet , Simonson Thomas , Ohanessian Gilles , Clavaguéra Carine
Published: December 2014

The association of Mg2+ and H2PO4− in water can give insights into Mg:phosphate interactions in general, which are very widespread, but for which experimental data is surprisingly sparse. It is studied through molecular dynamics simulations (>100 ns) by using the polarizable AMOEBA force field, and the association free energy is computed for the first time. Explicit consideration of outer‐sphere and two types of inner‐sphere association provides considerable insight into the dynamics and thermodynamics of ion pairing. After careful assessment of the computational approximations, the agreement with experimental values indicates that the methodology can be extended to other inorganic and biological Mg:phosphate interactions in solution.
Luminescence Properties of Ca2Ga2SiO7:RE Phosphors for UV White‐Light‐Emitting Diodes
Authors: Jiao Mengmeng , Lv Wenzhen , Lü Wei , Zhao Qi , Shao Baiqi , You Hongpeng
Published: December 2014

A series of Eu2+‐, Ce3+‐, and Tb3+‐doped Ca2Ga2SiO7 phosphors is synthesized by using a high‐temperature solid‐state reaction. The powder X‐ray diffraction and structure refinement data indicate that our prepared phosphors are single phased and the phosphor crystalizes in a tetrahedral system with the ${P\bar 42m}$ (113) space group. The Eu2+‐ and Ce3+‐doped phosphors both have broad excitation bands, which match well with the UV light‐emitting diodes chips. Under irradiation of λ=350 nm, Ca2Ga2SiO7:Eu2+ and Ca2Ga2SiO7:Ce3+, Li+ have green and blue emissions, respectively. Luminescence of Ca2Ga2SiO7:Tb3+, Li+ phosphor varies with the different Tb3+ contents. The thermal stability and energy‐migration mechanism of Ca2Ga2SiO7:Eu2+ are also studied. The investigation results indicate that the prepared Ca2Ga2SiO7:Eu2+ and Ca2Ga2SiO7:Ce3+, Li+ samples show potential as green and blue phosphors, respectively, for UV‐excited white‐light‐emitting diodes.
Subtle Differences in Initial Membrane Interactions Underpin the Selectivity of Small Antimicrobial Peptides
Authors: Praporski Slavica , Mechler Adam , Separovic Frances , Martin Lisandra L.
Published: December 2014

Host‐secreted antimicrobial peptides (AMPs) are found in virtually all organisms, often providing innate immunity as the first line of defence against pathogens. Many AMPs kill pathogens by disrupting their cellular membranes and thus are similar to some antibiotic drugs. Likely drug candidate AMPs are found in non‐mammalian hosts but are also haemolytic. Thus, it is crucial to understand the origins of membrane specificity and selectivity of the action of these AMPs. In this study, the membrane specificity of action of citropin 1.1, a 16‐residue AMP, was studied by using a quartz crystal microbalance on the basis of mass and viscoelasticity changes in comparison to aurein 1.2 (13 residues) and maculatin 1.1 (21 residues). The membrane selectivity was largely reflected in the nature of the initial interaction of the peptide with the membrane. This initial interaction might determine whether the peptide transforms into a membrane‐disrupting α‐helical conformation and highlights subtle differences in the repositioning of this α‐helical peptide in the membrane, as reflected by the viscoelasticity data, thus signifying the mechanistic pathway to membrane disruption.
Design of logical topology with K‐connected constraints and channel assignment for multi‐radio wireless mesh networks
Authors: Bao Xuecai , Tan Wenqun , Nie Jugen , Lu Changlong , Jin Guanglang
Published: December 2014

In multi‐radio multi‐channel wireless mesh networks, the design of logical topology is different from that in single channel wireless mesh networks. The same channel assignment algorithm used for various logical topologies will lead to diverse network performance. In this paper, we study the relationship between k‐connected logical topology and the maximum number of assigned channels. Meanwhile, we analyze the issues affecting channel assignment performance, and present the lower and upper bounds of the maximum allowable number of assigned channels for k‐connected logical topology. We then develop a k‐connected logical topology design algorithm based on shortest disjoint paths and minimum interference disjoint paths for each node‐pair. In addition, we propose a static channel assignment algorithm according to minimum spanning tree search. Extensive simulations show that our proposed algorithm achieves higher throughput and lower end‐to‐end delay than fault tolerant topology control algorithms, which validates the involved trade‐off between path length and nodal interference. Moreover, numerical results demonstrate that our proposed channel assignment further improves network performance under the context of limited radio interfaces. Copyright © 2014 John Wiley & Sons, Ltd.
Efficient data retrieval algorithms for multiple requests in MIMO wireless networks
Authors: He Ping , Shen Hong , Guo Longkun , Li Yidong
Published: December 2014

Given a set of multiple channels, a set of multiple requests, where each request contains multiple requested data items and a client equipped with multiple antennae, the multi‐antenna‐based multirequest data retrieval problem (DRMR‐MA) is to find a data retrieval sequence for downloading all data items of the requests allocated to each antenna, such that the maximum access latency of all antennae is minimized. Most existing approaches for the data retrieval problem focus on either single antenna or single request and are hence not directly applicable to DRMR‐MA for retrieving multiple requests. This paper proposes two data retrieval algorithms that adopt two different grouping schemes to solve DRMR‐MA so that the requests can be suitably allocated to each antenna. To find the data retrieval sequence of each request efficiently, we present a data retrieval scheme that converts a wireless data broadcast system to a special tree. Experimental results show that the proposed scheme is more efficient than other existing schemes. Copyright © 2014 John Wiley & Sons, Ltd.
Analysis of priority arbitration in low‐rate CSMA/CA‐based differentiated access with throughput optimization
Authors: Ashrafuzzaman Kazi , Fapojuwo Abraham O.
Published: December 2014

A class of applications, such as home energy management and control and utility data acquisition, is emerging in recent times where smart meters, sensors, and appliances are networked together for intelligent management and coordination. Such applications rely on low data rate communication of monitoring and control information at large scale. For the underlying networking infrastructure to facilitate communication of the real‐time and intermittent packet traffic expected, random access‐based protocols are regarded as suitable medium access control solutions. A key challenge in this regard is that the random access protocols are prone to throughput degradation when the number of contending nodes grows, as expected with the infrastructures involved. Besides, provision for certain degree of criticality/priority is needed for some of the packets compared with the rest. With this background, this paper analytically determines the criterion for throughput‐optimal operations in a network based on low‐ratecarrier sense multiple accessprotocol. In addition, ways to provide priority‐wise access differentiation at arbitrary proportions without a negative impact on the achievable throughput is incorporated within abinary exponential backoff‐basedcollision avoidance scheme. Discrete‐event simulations are performed to validate the accuracy of the approximations made in analysis.
Revamped note‐taking system ensures ease of use, confidentiality
Authors: Kolin Kristin , Eksheir Khaleel
Published: December 2014

Note‐taking is one of the most frequently used disability accommodations on college and university campuses. While there are numerous ways to provide students with supplemental notes, many disability services offices struggle with creating a system that is both consistent and confidential.
Understand how to evaluate requests for emotional support animals as classroom accommodations
Authors: Masinter Michael R.
Published: December 2014

The Fair Housing Act requires housing providers to offer reasonable accommodations to residents with disabilities to enable those residents an equal opportunity to use and enjoy their dwelling. The courts and the Department of Housing and Urban Development have ruled that campus housing is a dwelling under the FHA. And HUD and some courts have ordered housing providers to modify “no pets” rules as a reasonable accommodation for residents who rely on emotional support animals to ameliorate the effects of psychiatric disabilities. As a result, an increasing number of students now live in campus housing with their emotional support animals.
CRISPR/Cas9‐mediated genome modification in the mollusc, Crepidula fornicata
Authors: Perry Kimberly J. , Henry Jonathan Q.
Published: December 2014

The discovery and application of the CRISPR/Cas9 genome editing method has greatly enhanced the ease with which transgenic manipulation can occur. We applied this technology to the mollusc, Crepidula fornicata, and have successfully created transgenic embryos expressing mCherry fused to endogenous β‐catenin. Specific integration of the fluorescent reporter was achieved by homologous recombination with a β‐catenin‐specific donor DNA containing the mCherry coding sequence. This fluorescent gene knock‐in strategy permits in vivo observations of β‐catenin expression during embryonic development and represents the first demonstration of CRISPR/Cas9‐mediated transgenesis in the Lophotrochozoa superphylum. The CRISPR/Cas9 method is a powerful and economical tool for genome modification and presents an option for analysis of gene expression in not only major model systems, but also in those more diverse species that may not have been amenable to the classic methods of transgenesis. This approach will allow one to generate transgenic lines of snails for future studies. genesis 53:237–244, 2015. © 2014 Wiley Periodicals, Inc.
Computational Insights into the Isomerism of Hexacoordinate Metal–Sarcophagine Complexes: The Relationship between Structure and Stability
Authors: Algarra Andrés G.
Published: December 2014

The hexacoordinate complexes that the macrobicyclic ligands {(NH3)2sar}2+ and {(NMe3)2sar}2+ (sar = 3,6,10,13,16,19‐hexaazabicyclo[6.6.6]icosane) form with transition metals such as CoIII, CoII and CuII can adopt several isomeric structures. In this article, we have firstly employed DFT methods to compute the relative stability of their Δ‐ob3, Δ‐ob2lel, Δ‐lel2ob and Δ‐lel3 isomers, as well as the activation barriers for their interconversion. In agreement with the experimental data, the results show that, in general, the different isomers of the CoIII and CoII complexes present similar free energies, whereas the CuII complexes show a strong tendency towards the lel3 form. In addition, the interplay between the structure and stability of these species has been studied by combining shape maps with a distortion/interaction energy analysis. In contrast to the geometries close to the ideal octahedron that all the studied Co complexes present, the lel3 structures of [Cu{(NH3)2sar}]4+ and [Cu{(NMe3)2sar}]4+ are better described as trigonal prisms. In such structures the ligand adopts a conformation significantly more stable than in the other isomers, and this drives the formation of lel3‐[Cu{(NH3)2sar}]4+ and lel3‐[Cu{(NMe3)2sar}]4+. Overall, the results show a clear relationship between the stability of a given isomer and its degree of distortion with respect to the ideal octahedron (or trigonal prism), with the latter being ultimately dependent on the transition metal and its radius.
Continuous enzymatic interesterification of milkfat with soybean oil produces a highly spreadable product rich in polyunsaturated fatty acids
Authors: Paula Ariela V. , Nunes Gisele F. M. , Osório Natália M. , Santos Júlio C. , de Castro Heizir F. , Ferreira‐Dias Suzana
Published: December 2014

The aim of this study was to tune the physical properties of milkfat by enzymatic interesterification with soybean oil in a continuous fluidized bed reactor (FBR) to obtain healthy interesterified fat blends having suitable texture properties for the food industry. The immobilized commercial non‐regioselectiveCandida antarcticalipase (Novozym®435) andsn1,3‐regioselectiveRhizopus oryzaelipase, immobilized in an organic‐inorganic hybrid matrix of polysiloxane‐polyvinyl alcohol, were used as biocatalysts in a FBR. The minimum value of the ascendant flow of the medium for allowing fluidization in the system was 3.13 mL·min−1. The reaction was evaluated in terms of the interesterification yield (IY), consistency values and solid fat content (SFC). The IY values of 10.50 ± 1.64% and of 5.70 ± 1.46% were attained for Novozym®435 and for immobilizedR. oryzaelipase, respectively. The consistency of the initial 65:35 milkfat/soybean oil mixture (1000 gf/cm2) decreased to 732.35 ± 75.30 gf/cm2and to 478.02 ± 71.80 gf/cm2in interesterified blends catalyzed by Novozym®435 or byR. oryzaelipase, respectively. SFC was considered an inadequate parameter for following the interesterification of this blend formulation because the values were similar for initial and for interesterified blends. Free fatty acid levels of 1.5%, the non‐notable deactivation of Novozym®435 and a half‐life of 190 h forR. oryzaelipase were observed during the operation time.

Practical applications:By interesterification of milkfat with soybean oil, a new product presenting higher spreadability than butter and richer in polyunsaturated fatty acids coming from soybean oil, was obtained. TheRhizopus oryzaelipase immobilized in an organic‐inorganic hybrid matrix, used in a FBR for the modification of milkfat, promoted a higher reduction (approximately 52.0%) in the consistency of the interesterified products in relation to the initial reaction mixture than that obtained with Novozym® 435 (approximately 27.0% reduction). Also, while Novozym® 435 is as a non‐specific lipase, theR. oryzaelipase presentssn‐1,3 regioselectivity, which enables the maintenance of the unsaturated fatty acids at positionsn‐2 in triacylglycerols with well‐known nutritional benefits. This biocatalyst showed a better performance than the immobilized commercial lipase (Novozym® 435). The implementation of the interesterification in a continuous FBR results in lower shear rate imposed on the biocatalyst.

The consistency of the initial milkfat/soybean blend (65:35,% w/w) decreased about 52% or 27% after interesterification in a continuous fluidized bed reactor, catalyzed by the immobilized Rhizopus oryzae lipase or by Novozym 435, respectively.
Synthesis and Properties of 5,7‐Dihydropyrido[3,2‐b:5,6‐b′]diindoles
Authors: Hung Tran Quang , Thang Ngo Ngoc , Hoang Do Huy , Dang Tuan Thanh , Ayub Khurshid , Villinger Alexander , Lochbrunner Stefan , Flechsig Gerd‐Uwe , Langer Peter
Published: December 2014

5,7‐Dihydropyrido[3,2‐b:5,6‐b′]diindoles were prepared by a highly efficient two‐step synthesis that involved a site‐selective Suzuki coupling reaction of 2,3,5,6‐tetrabromopyridine and a subsequent Pd‐catalyzed cyclization that proceeded through a twofold C–N coupling reaction with aromatic and aliphatic amines. With the exception of the parent molecule, which was described in a patent without any characterization data, the 5,7‐dihydropyrido[3,2‐b:5,6‐b′]diindoles are a new chemical entity. Their electrochemical and photochemical properties were investigated. These pyridodiindoles show promising fluorescence properties with good quantum yields and interesting electrochemical behavior. The optical and electronical properties were analyzed and explained by using DFT calculations.
AlCl3‐Catalyzed [3+2] Annulations of cis‐2,3‐Disubstituted Cyclopropane 1,1‐Diesters with Cyclic Ketones: Diastereoselective Construction of Spirotetrahydrofurans
Authors: Yang Gaosheng , Wang Tingting , Chai Jun , Chai Zhuo
Published: December 2014

The stereoselective [3+2] annulations of cis‐2,3‐disubstituted cyclopropane 1,1‐diesters with cyclic/acyclic aliphatic ketones were effected by AlCl3 to provide highly functionalized spirotetrahydrofurans in moderate to excellent yields under very mild conditions.
The Reversible Nicholas Reaction in the Synthesis of Highly Symmetric Natural‐Product‐Based Macrocycles
Authors: de la Torre María C. , Asenjo María , Ramírez‐López Pedro , Sierra Miguel A.
Published: December 2014

Two different approaches to highly symmetric macrocycles by reversible Nicholas reactions have been developed. The first sequence uses a bis[Co2(CO)6] complex derived from a double propargylic alcohol supporting two natural product moieties. The reactions with BF3·OEt2 and different benzene dimethanols yielded either (1:1) or (2:2) adducts, depending essentially on the nature of the tether joining both Co clusters. Alternatively, the Nicholas reactions of Co‐complexed propargyl alcohol templates with one steroid and one monoterpene fragment as well as one aromatic terminus containing an alcohol moiety yielded the corresponding macrocycles derived from self‐dimerization. Both routes to macrocycles are complementary and efficiently produce sophisticated natural‐product‐containing structures.
Lithium Choreography Determines Contrasting Stereochemical Outcomes of Aryl Migrations in Benzylic Carbamates, Ureas and Thiocarbamates
Authors: Vincent Mark A. , Maury Julien , Hillier Ian H. , Clayden Jonathan
Published: December 2014

The intramolecular arylation reactions of lithiated derivatives of ureas, carbamates and thiocarbamates generally proceed stereospecifically, but the reaction is stereochemically retentive with ureas and thiocarbamates, whereas it is stereochemically invertive with carbamates. Using DFT calculations, we have studied the mechanism of the intramolecular attack of a thiocarbamate‐stabilised carbanion on an N‐aryl substituent and compared the details of the calculated reaction pathway with the corresponding reactions of carbamate‐ and urea‐stabilised carbanions. The different stereochemical outcomes observed in the rearrangements of carbamates and thiocarbamates arise from the sulfur–carbon interaction in the thiocarbamate, which enhances the stabilisation of the anion. As a result, the solvated lithium cation takes different pathways across the potential energy surfaces that lead to stereochemically divergent outcomes. Additionally, we investigated the importance of the intramolecular nature of the aryl migration and compared the pathway for aryl migration within a urea with that of a hypothetical, experimentally unfeasible, intermolecular reaction. The results throw light on the reason why aryl migrations are successful even with much more electron‐rich rings than would be tolerated in a typical intermolecular nucleophilic aromatic substitution.
Overview review: Comparative efficacy of oral ibuprofen and paracetamol (acetaminophen) across acute and chronic pain conditions
Authors: Moore R.A. , Derry S. , Wiffen P.J. , Straube S. , Aldington D.J.
Published: December 2014

Background

Ibuprofen and paracetamol have long been used as analgesics in a range of acute, intermittent and chronic pain conditions. Paracetamol is often the first line analgesic recommended, without consensus about which is the better analgesic.

Methods

An overview review of systematic reviews and meta‐analyses directly compares ibuprofen and paracetamol at standard doses in particular painful conditions, or uses indirect comparisons against placebo. Electronic searches for systematic reviews were sought published since 1995 using outcomes approximating to ≥50% pain intensity reduction. Painful conditions were acute post‐operative pain, dysmenorrhoea, tension‐type headache (TTH), migraine, osteoarthritis and rheumatoid arthritis, back pain, cancer and paediatric pain. There was no systematic assessment of harm.

Results

Sixteen systematic reviews and four individual patient data meta‐analyses were included. Ibuprofen was consistently superior to paracetamol at conventional doses in a range of painful conditions. Two direct comparisons favoured ibuprofen (acute pain, osteoarthritis). Three of four indirect comparisons favoured ibuprofen (acute pain, migraine, osteoarthritis); one showed no difference (TTH), although there were methodological problems. In five pain conditions (dysmenorrhoea, paediatric pain, cancer pain, back pain and rheumatoid arthritis), there were limited data on paracetamol and ibuprofen.

Conclusions

At standard doses in different painful conditions, ibuprofen was usually superior producing more patients with the degree of pain relief that patients feel worthwhile. Neither of the drugs will be effective for everyone, and both are needed. This overview questions the practice of routinely using paracetamol as a first line analgesic because there is no good evidence for efficacy of paracetamol in many pain conditions.
A Final Note About Improving Needs Assessment Research and Practice
Authors: Watkins Ryan , Altschuld James W.
Published: December 2014

As with any field of inquiry and application, needs assessment is an evolving topic of research and practice. The theories, models, tools, and approaches are not idle targets. In this chapter, the authors explore the emerging trends and issues of the field, suggesting elements of an exciting future and the continuing call for more research that can improve practice. They include an examination of how technologies are expanding the methods employed in assessments and a discussion of how many of the challenges that have nagged at assessors for decades continue to limit our results. The future for needs assessments remains bright, but much work remains to be done in order for needs assessment to mature as a field.
Multicolor analysis of oligodendrocyte morphology, interactions, and development with Brainbow
Authors: Dumas Laura , Heitz‐Marchaland Céline , Fouquet Stephane , Suter Ueli , Livet Jean , Moreau‐Fauvarque Caroline , Chédotal Alain
Published: December 2014

Oligodendrocytes are the myelinating cells of the central nervous system. Multiple markers are available to analyze the populations of oligodendroglial cells and their precursors during development and in pathological conditions. However, the behavior of oligodendrocytes remains poorly characterized in vivo, especially at the level of individual cells. Studying this aspect has been impaired so far by the lack of suitable methods for visualizing single oligodendrocytes, their processes, and their interactions during myelination. Here, we have used multicolor labeling technology to single‐out simultaneously many individual oligodendrocytes in the postnatal mouse optic nerve. This method is based on Brainbow, a transgenic system for stochastic expression of multiple fluorescent protein genes through Cre‐lox recombination, previously used for visualizing axons and neurons. We used tamoxifen‐inducible recombination in myelinating cells of Brainbow transgenic mice to obtain multicolor labeling of oligodendrocytes. We show that the palette of colors expressed by labeled oligodendrocytes is tamoxifen dependent, with the highest doses producing the densest and most colorful labeling. At low doses of tamoxifen, the morphology of single or small clusters of fluorescent oligodendrocytes can be studied during postnatal development and in adult. Internodes are labeled to their extremities, revealing nodes of Ranvier. The new mouse model presented here opens new possibilities to explore the organization and development of the oligodendrocyte network with single‐cell resolution. GLIA 2015;63:699–717
Extended vertical lower trapezius island myocutaneous flap versus pectoralis major myocutaneous flap for reconstruction in recurrent oral and oropharyngeal cancer
Authors: Chen Wei‐liang , Wang You‐yuan , Zhang Da‐ming , Fan Song , Lin Zhao‐yu
Published: December 2014

Background

The purpose of this study was to compare the use of an extended vertical lower trapezius island myocutaneous flap (TIMF) and a pectoralis major myocutaneous flap (PMMF).

Methods

A total of 39 patients with advanced recurrent oral and oropharyngeal squamous cell carcinoma (SCC) underwent salvage surgery followed by placement of either an extended lower vertical TIMF or PMMF for reconstruction. Twenty‐one patients received extended lower vertical TIMFs, whereas 18 received PMMFs.

Results

The pedicle length of the TIMF was longer than that of the PMMF, and the skin paddle of the TIMF was both wider and longer than the PMMF. No major complication developed in any of the patients. The TIMF group experienced a lower rate of minor flap failure than did the PMMF group.

Conclusion

Use of an extended vertical lower TIMF, which has a longer pedicle flap and a larger skin paddle than a PMMF, is optimal for reconstruction of major defects. © 2015 Wiley Periodicals, Inc. Head Neck 38: E159–E164, 2016
Taxonomy and structure of Persian personality‐descriptive trait terms
Authors: Farahani Mohammad N. , De Raad Boele , Farzad Valiolla , Fotoohie Mahmood
Published: December 2014

We described the development of a taxonomy of Persian personality‐descriptive terms in two studies. In Study 1, judges scanned Persian dictionaries and several Persian novels for person‐descriptive terms. The resulting set of person‐descriptive terms was classified into different categories of description, including the category of dispositional trait‐descriptive adjectives. Of the 544 most familiar traits, 126 traits were selected to collect self‐ratings. In Study 2, self‐ratings were provided by 2400 students. Ratings were factor analysed (Principal Components Analysis) followed by Varimax rotation. Factor structures with two to six factors were discussed. The two‐factor structure and the three‐factor structure confirm the Big Two and the Big Three, respectively. Of the structures with five and six factors, the five‐factor structure appears to be the more appropriate choice, with the factors labelled Morality, Positive versus Negative Emotionality, Achievement, Thoughtfulness and Affection. Gender differences were measured on both the five‐factor structure and the six‐factor structure. The discussion section emphasised both cross‐cultural commonalities and cultural deviations in reference to the Big Five.
Critical Literacy and Social Justice
Authors: Comber Barbara
Published: December 2014

Given the global escalation of gaps between rich and poor, contemporary work in critical literacy needs to overtly question the politics of poverty. How and where is poverty produced, by what means, by whom and for whom and how are educational systems stratified to provide different kinds of education to the rich and the poor? Yet rather than critical literacy, international educational reform movements stress performative standards on basic literacy. In this context literacy researchers need to ask policy‐makers hard questions about taken‐for‐granted rhetoric that surrounds poverty, literacy and education. At school, regional and state levels, educational leaders need to argue for fair resourcing and decision‐making for their communities and students. In classrooms teachers need to weave critical questioning and inclusive learning interactions into the fabric of everyday life.
Enacting Critical Literacy in English Classrooms
Authors: Riley Kathleen
Published: December 2014

In a time of increased standardization and top‐down reform, teachers with democratic and social justice‐oriented perspectives must work to create classroom spaces that value student voice and position them as knowledge holders. This article draws on a critical literacy framework to analyze the case study of one teacher working within a teacher study group on adolescent literacy education in a large urban area. This teacher re‐articulated her values in the context of a constraining school culture, made sense of her practice in order to improve it, and considered how she might negotiate the micropolitical environment of her school. The article concludes with a discussion of how the study group provided structured support for this teacher's inquiry and discusses how teachers can work together to open more space for enacting critical literacy practices within constraining policy environments.
Role of the Parathyroid Hormone Type 1 Receptor (PTH1R) as a Mechanosensor in Osteocyte Survival
Authors: Maycas Marta , Ardura Juan A , de Castro Luis F , Bravo Beatriz , Gortázar Arancha R , Esbrit Pedro
Published: December 2014

Osteocytes have a major role in the control of bone remodeling. Mechanical stimulation decreases osteocyte apoptosis and promotes bone accrual, whereas skeletal unloading is deleterious in both respects. PTH1R ablation or overexpression in osteocytes in mice produces trabecular bone loss or increases bone mass, respectively. The latter effect was related to a decreased osteocyte apoptosis. Here, the putative role of PTH1R activation in osteocyte protection conferred by mechanical stimulation was assessed. Osteocytic MLO-Y4 cells were subjected to mechanical stimuli represented by hypotonic shock (216 mOsm/kg) or pulsatile fluid flow (8 Hz, 10 dynes/cm2) for a short pulse (10 min), with or without PTH1R antagonists or after transfection with specific PTHrP or PTH1R siRNA. These mechanical stimuli prevented cell death induced within 6 hours by etoposide (50 μM), related to PTHrP overexpression; and this effect was abolished by the calcium antagonist verapamil (1 μM), a phospholipase C (PLC) inhibitor (U73122; 10 μM), and a PKA activation inhibitor, Rp-cAMPS (25 μM), in these cells. Each mechanical stimulus also rapidly induced β-catenin stabilization and nuclear ERK translocation, which were inhibited by the PTH1R antagonist PTHrP(7–34) (1 μM), or PTH1R siRNA, and mimicked by PTHrP(1–36) (100 nM). Mechanical stretching by hypotonic shock did not affect cAMP production but rapidly (<1 min) stimulated Cai2+ transients in PTH1R-overexpressing HEK-293 cells and in MLO-Y4 cells, in which calcium signaling was unaffected by the presence of a PTHrP antiserum or PTHrP siRNA but inhibited by knocking down PTH1R. These novel findings indicate that PTH1R is an important component of mechanical signal transduction in osteocytic MLO-Y4 cells, and that PTH1R activation by PTHrP-independent and dependent mechanisms has a relevant role in the prosurvival action of mechanical stimulus in these cells. © 2014 American Society for Bone and Mineral Research © 2014 American Society for Bone and Mineral Research
Assessing Corporate Governance in M&As
Authors: Shapiro David M.
Published: December 2014

This article considers how to assess whether the leadership of a merger and acquisition (M&A) target includes essential human resource from the acquirer's point of view. After all, M&A should be seen for what it is: a primarily privately controlled reordering of economic, financial, and human resources that occasionally leaves significant disruption in its wake. M&A needs to consider more than accounting and financial issues, thus becoming more professionalized, broader minded, and less exploitative and parochial.
Structural study of a lead (II) organic complex – a key precursor in a green recovery route for spent lead‐acid battery paste
Authors: Zhang Wei , Yang Jiakuan , Zhu Xinfeng , Sun Xiaojuan , Yu Wenhao , Hu Yuchen , Yuan Xiqing , Dong Jinxin , Hu Jingping , Liang Sha , Kumar Ramachandran Vasant
Published: December 2014

BACKGROUND

Lead citrate is an attractive precursor for the preparation of ultrafine leady oxide from the paste in spent lead‐acid batteries through a novel hydrometallurgical process, since the recovered lead oxide could be recycled for the production of new lead acid batteries.

RESULTS

Two different metal organic complexes were synthesized from lead sulfate from the paste of spent lead‐acid batteries in a leaching solution at two different initial pH values. Single crystals of the two precursors were obtained by conditioning and filtering from the leached solutions, and used for single crystal XRD analysis. At an initial pH of 3.5, the chemical formula of Precursor‐I is deduced to be Pb(C6H6O7)·H2O while at an initial pH of 5.2, the chemical formula of Precursor‐II is Pb3(C6H5O7)2·3H2O.

CONCLUSIONS

Both Precursor‐I and Precursor‐II crystallize in the triclinic crystal system, with space group P‐1. This structural study on precursors sheds light on the mechanism of a paste‐to‐paste recovery route for the recovery of spent lead paste. © 2014 Society of Chemical Industry
Synthesis of Novel Fused Thiazolo[3,2‐a]pyrimidin‐3‐ols and Evaluation for their Antibacterial Activity
Authors: Velpula Ravibabu , Banothu Janardhan , Gali Rajitha , Bavantula Rajitha
Published: December 2014

A series of novel fused thiazolo[3,2‐a]pyrimidin‐3‐ol derivatives have been synthesized by reaction of fused pyrimidine‐thiones with 4‐substituted phenacyl bromide/3(2‐bromoacetyl)coumarin in refluxing acetic acid with good yields. All the synthesized compounds were confirmed by spectral studies and screened for their in vitro antibacterial activity against Staphylococcus aureus, Bacillus thuringiensis (Gram positive), Escherichia coli, and Klebsiella pneumoniae (Gram negative) bacterial strains. Activity results revealed that all the compounds were weak to good active against the tested bacterial strains on comparing with the standard drug gentamicin.
The Reactivity of Dimethyl Acetylenedicarboxylate and Heterocyclization of Hydrazinecarbothioamides to 1,3‐Thiazolidin‐4‐ones
Authors: Hassan Alaa A. , Mohamed Nasr K. , El‐Shaieb Kamal M. A. , Tawfeek Hendawy N. , Bräse Stefan , Nieger Martin
Published: December 2014

2‐Substituted hydrazinecarbothioamides and N,2‐disubstituted hydrazinecarbothioamides react, in high yields with dimethyl acetylenedicarboxylate to give 4‐oxo‐Z‐(thiazolidin‐5‐ylidene)acetate derivatives. Several mechanistic options involving interaction are presented. The structures of thiazolidin‐4‐ones have been unambiguously confirmed by single crystal X‐ray crystallography.
Investigation of the vibrational modes of ZnO grown by MOCVD on different orientation planes
Authors: Jabri S. , Souissi H. , Souissi A. , Meftah A. , Sallet V. , Lusson A. , Galtier P. , Oueslati M.
Published: December 2014

Wurtzite ZnO thin films were prepared on sapphire substrate by metal organic chemical vapor deposition (MOCVD). Raman scattering studies on different crystallographic textures were performed in the backscattering geometry, and polarization effect is investigated in different configurations and . ZnO Raman modes are investigated in each texture. In the case of ZnO thin film deposed on r‐() sapphire plane and using backscattering geometry, new Raman line was observed at 390 cm−1 because this mode has not been noticed in this geometry. It is shown that the frequencies of the quasi‐phonon modes of the examined thin film are in good agreement with the theoretical values calculated within the framework of Loudon model. Copyright © 2014 John Wiley & Sons, Ltd.
Shedding light onto the spectra of lime: Raman and luminescence bands of CaO, Ca(OH)2 and CaCO3
Authors: Schmid Thomas , Dariz Petra
Published: December 2014

In microscopy studies of 19th‐century cement stone, we found free lime in the form of darkened spherical structures, as they were described in the literature already. When trying to determine their phase composition by Raman spectroscopy, we encountered contradictive assignments in literature spectra of the lime phases CaO, Ca(OH)2 and CaCO3 and observed strong spectral features that have been ignored or erroneously assigned so far. In this study we present Raman spectra of pure lime phases and of a naturally grown calcite crystal, burnt limestone (quick lime, mainly CaO), aged slaked lime putty (mainly Ca(OH)2), and carbonated lime putty (mainly CaCO3). Based on the results, we shed light mainly onto these two questions: (1) Does CaO have a Raman spectrum? (2) Which features in the spectra are luminescence bands that could be (and already have been) misinterpreted as Raman bands? We proof our assignment of luminescence bands in lime phases by using three different laser wavelengths for excitation, and give hypotheses on the origin of the luminescence as well as practical advices on how to identify these misleading features in Raman spectra. This article is mainly addressed to users of Raman spectroscopy in different fields of material analysis who might not be aware of the presence of interfering bands in their spectra. Copyright © 2014 John Wiley & Sons, Ltd.
Hydrogen‐Bonding Effects for the C–ON Bond Homolysis and Reformation Reactions of Alkoxyamines
Authors: Bagryanskaya Elena G. , Brémond Paul , Butscher Teddy , Marque Sylvain R. A. , Parkhomenko Dmitry , Roubaud Valérie , Siri Didier , Viel Stéphane
Published: December 2014

N‐(2‐methylpropyl)‐N‐(1‐diethylphosphono‐2,2‐dimethylpropyl)‐O‐(2‐carboxyprop‐2‐yl) hydroxylamine (BlocBuilder MA) is, among the commercially available alkoxyamines, one of the most efficient for nitroxide‐mediated polymerization (NMP). However, recent results have shown that it does not perform well for the NMP of isoprene. The occurrence of intramolecular hydrogen bonding (IHB) between the carboxylic function and the diethoxyphosphoryl group has been proposed as the reason for its low efficiency. In this article, the presence of this IHB is confirmed using IR, 31P NMR, 31P‐1H HOESY, and DFT calculation results. The solvent effect on this IHB and consequently on kd values is also investigated. However, combining kinetic analysis and rate measurements in various solvents, the influence of this IHB on the CON bond homolysis and reformation in alkoxyamine is shown to be very weak.

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Self‐Assembly of Amphiphilic Block Copolypeptoids with C2‐C5 Side Chains in Aqueous Solution
Authors: Fetsch Corinna , Flecks Silvana , Gieseler Dan , Marschelke Claudia , Ulbricht Juliane , van Pée Karl‐Heinz , Luxenhofer Robert
Published: December 2014

Nowadays, amphiphilic molecules play an important role in our life. In medical applications, amphiphilic block copolymers have attracted much attention as excipients in drug delivery systems. Here, the polymers are used as emulsifiers, micelles, or polymersomes with a hydrophilic corona block and a hydrophobic core or membrane. The aggregation behavior in aqueous solutions of a series of different amphiphilic block copolypeptoids comprising polysarcosine as a hydrophilic part is here reported. The formation of aggregates is investigated with 1H NMR spectroscopy and dynamic light scattering, and the determination of the critical micelle concentration (cmc) is performed using pyrene fluorescence spectroscopy. For the different block copolypeptoids cmc values ranging from 0.6 × 10−6m to 0.1 × 10−3m are found. The tendency to form micelles increases with increasing hydrophobicity at the nitrogen side chain in the hydrophobic moiety. Furthermore, in the case of the same hydrophobic side chain, a decreasing hydrophilic/lipophilic balance leads to the formation of larger aggregates. The aggregates formed in the buffer are able to solubilize the hydrophobic model compounds Reichardt's dye and pyrene, and exhibit versatile microenvironments. Final investigations about the cytotoxicity reveal that the block copolypeptoids are well tolerated by mammalian cells up to high concentrations.

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The Self‐Healing Potential of Triazole‐Pyridine‐Based Metallopolymers
Authors: Sandmann Benedict , Happ Bobby , Kupfer Stephan , Schacher Felix H. , Hager Martin D. , Schubert Ulrich S.
Published: December 2014

The development of artificial self‐healing materials represents an emerging and challenging field in material science. Inspired by nature—for instance by the self‐healing of mussel byssus threads—metallopolymers gain more and more attention as attractive self‐healing materials. These compounds are able to combine the properties of both polymers and metal–ligand interactions. A novel metallopolymer is developed consisting of attached bidentate triazole‐pyridine (TRZ‐py) ligands and a low glass transition temperature (T
g) lauryl methacrylate backbone. The polymer is cross‐linked with different Fe(II) and Co(II) salts. The resulting materials exhibit promising self‐healing performance within time intervals of 5.5 to 26.5 h at moderate temperatures of 50 to 100 °C. The materials are characterized by X‐ray scattering (SAXS), UV–Vis spectroscopy, and light microscopy.

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pH‐Switchable Self‐Assembled Materials
Authors: Frisch Hendrik , Besenius Pol
Published: December 2014

Self‐assembled materials, which are able to respond to external stimuli, have been extensively studied over the last decades. A particularly exciting stimulus for a wide range of biomedical applications is the pH value of aqueous solutions, since deprotonation‐protonation events are crucial for structural and functional properties of biopolymers. In living cells and tissues, intra‐ and extracellular pH values are stringently regulated, but can deviate from pH neutral as observed for example in tumorous, inflammatory sites, in endocytic pathways, and specific cellular compartments. By using a pH‐switch as a stimulus, it is thereby possible to address specific targets in order to cause a programmed response of the supramolecular material. This strategy has not only been successfully applied in fundamental research but also in clinical studies. In this feature article, current strategies that have been used in order to design materials with pH‐responsive properties are illustrated. This discussion only addresses selected examples from the last four years, the self‐assembly of polymer‐based building blocks, assemblies emerging from small molecules including surfactants or derived from biological macromolecules, and finally the controlled self‐assembly of oligopeptides.

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Targeted Prodrug Approaches for Hormone Refractory Prostate Cancer
Authors: Aloysius Herve , Hu Longqin
Published: December 2014

Due to the propensity of relapse and resistance with prolonged androgen deprivation therapy (ADT), there is a growing interest in developing non‐hormonal therapeutic approaches as alternative treatment modalities for hormone refractory prostate cancer (HRPC). Although the standard treatment for HRPC consists of a combination of ADT with taxanes and anthracyclines, the clinical use of chemotherapeutics is limited by systemic toxicity stemming from nondiscriminatory drug exposure to normal tissues. In order to improve the tumor selectivity of chemotherapeutics, various targeted prodrug approaches have been explored. Antibody‐directed enzyme prodrug therapy (ADEPT) and gene‐directed enzyme prodrug therapy (GDEPT) strategies leverage tumor‐specific antigens and transcription factors for the specific delivery of cytotoxic anticancer agents using various prodrug‐activating enzymes. In prostate cancer, overexpression of tumor‐specific proteases such as prostate‐specific antigen (PSA) and prostate‐specific membrane antigen (PSMA) is being exploited for selective activation of anticancer prodrugs designed to be activated through proteolysis by these prostate cancer‐specific enzymes. PSMA‐ and PSA‐activated prodrugs typically comprise an engineered high‐specificity protease peptide substrate coupled to a potent cytotoxic agent via a linker for rapid release of cytotoxic species in the vicinity of prostate cancer cells following proteolytic cleavage. Over the past two decades, various such prodrugs have been developed and they were effective at inhibiting prostate tumor growth in rodent models; several of these prodrug approaches have been advanced to clinical trials and may be developed into effective therapies for HRPC.
Multi‐component integrable couplings for the Ablowitz–Kaup–Newell–Segur and Volterra hierarchies
Authors: Shen Shoufeng , Li Chunxia , Jin Yongyang , Yu Shuimeng
Published: December 2014

A kind of N × N non‐semisimple Lie algebra consisting of triangular block matrices is used to generate multi‐component integrable couplings of soliton hierarchies from zero curvature equations. Two illustrative examples are made for the continuous Ablowitz–Kaup–Newell–Segur hierarchy and the semi‐discrete Volterra hierarchy, together with recursion operators. Copyright © 2014 John Wiley & Sons, Ltd.
Positive solutions for p‐Kirchhoff type problems on
Authors: Cheng Xiyou , Dai Guowei
Published: December 2014

In this paper, we establish the existence and non‐existence of positive solutions for p‐Kirchhoff type problems with a parameter on
without assuming the usual compactness conditions. We show that the p‐Kirchhoff type problems have at least one positive solution when the parameter is small, while the p‐Kirchhoff type problems have no positive solutions when the parameter is large. Our argument is based on variational methods, monotonicity methods, cut‐off functional techniques, and a priori estimates techniques. Copyright © 2014 John Wiley & Sons, Ltd.
The effect of iron in MRI and transverse relaxation of amyloid‐beta plaques in Alzheimer's disease
Authors: Meadowcroft Mark D. , Peters Douglas G. , Dewal Rahul P. , Connor James R. , Yang Qing X.
Published: December 2014

Dysregulation of neural iron is known to occur during the progression of Alzheimer's disease. The visualization of amyloid‐beta (Aβ) plaques with MRI has largely been credited to rapid proton relaxation in the vicinity of plaques as a result of focal iron deposition. The goal of this work was to determine the relationship between local relaxation and related focal iron content associated with Aβ plaques. Alzheimer's disease (n = 5) and control tissue (n = 3) sample slices from the entorhinal cortex were treated overnight with the iron chelator deferoxamine or saline, and microscopic gradient‐echo MRI datasets were taken. Subsequent to imaging, the same slices were stained for Aβ and iron, and then compared with regard to parametric R2* relaxation maps and gradient‐echo‐weighted MR images. Aβ plaques in both chelated and unchelated tissue generated MR hypo‐intensities and showed relaxation rates significantly greater than the surrounding tissue. The transverse relaxation rate associated with amyloid plaques was determined not to be solely a result of iron load, as much of the relaxation associated with Aβ plaques remained following iron chelation. The data indicate a dual relaxation mechanism associated with Aβ plaques, such that iron and plaque composition synergistically produce transverse relaxation.Copyright © 2014 John Wiley & Sons, Ltd.