bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polyaniline as a Material for Hydrogen Storage Applications
Authors: Attia Nour F. , Geckeler Kurt E. 
Published: June 2013

AbstractThe main challenge of commercialization of the hydrogen economy is the lack of convenient and safe hydrogen storage materials, which can adsorb and release a significant amount of hydrogen at ambient conditions. Finding and designing suitable cost‐effective materials are vital requirements to overcome the drawbacks of investigated materials. Because of its outstanding electronic, thermal, and chemical properties, the electrically conducting polyaniline (PANI) has a high potential in hydrogen storage applications. In this review, the progress in the use of different structures of conducting PANI, its nanocomposites as well as activated porous materials based on PANI as hydrogen storage materials is presented and discussed. The effect of the unique electronic properties based on the π‐electron system in the backbone of these materials in view of the hydrogen uptake and the relevant mechanisms are highlighted.magnified image
pH‐Switchable Macroscopic Assembly through Host–Guest Inclusion
Authors: Yuan Qi‐Juan , Wang Yi‐Fu , Li Jian‐Hu , Li Bang‐Jing , Zhang Sheng 
Published: June 2013

AbstractA novel pH‐switchable macroscopic assembly is reported using alginate‐based hydrogels functionalized with host (α‐cyclodextrin, αCD) and guest (diethylenetriamine, DETA) moieties. Since the interaction of αCD and DETA is pH sensitive, the host hydrogel and guest hydrogel could adhere together when the pH is 11.5 and separate when the pH is 7.0. Furthermore, this pH‐controlled adhesion and dissociation shows a good reversibility. The host and guest polymers have good biocompatibility; therefore, this pH‐sensitive macroscopic assembly shows great potential in biotechnological and biomedical applications.magnified image
Tooth Wear Related to Marine Foraging, Agro‐Pastoralism and the Formative Transition on the Northern Chilean Coast
Authors: Watson J. T. , Arriaza B. , Standen V. , Muñoz Ovalle I. 
Published: June 2013

ABSTRACTOcclusal surface wear scores were examined in a sample of 200 Formative period (1500 bc–ad 500) skeletons from the lower Azapa Valley in northwest Chile. Wear rate and plane (angle) were additionally evaluated using a subsample of paired first and second mandibular molars. The Formative period represents the transition from marine foraging to agro‐pastoral dependence in the region, and differences in oral pathology indicate that diet varied by site location (coast vs valley interior) but not by archaeological phase (early vs late). We predicted that occlusal wear would demonstrate similar patterns, resulting from differences in food consistency, and therefore hypothesised that in coastal groups consuming greater quantities of foraged foods, occlusal surfaces should wear faster and exhibit flat molar wear, whereas among valley interior groups consuming greater quantities of agro‐pastoral products, these should wear slower but exhibit more angled molar wear. Heavier posterior tooth wear was identified among coastal residents, but rate and angle of molar occlusal attrition did not differ significantly by location. Heavier overall wear and a steeper molar wear plane were identified during the early phase indicating that food consistency varied somewhat over the course of the Formative period. Overall, the results indicate that, although limited differences in tooth wear exist by site location, wear varied more over time likely reflecting a gradual transition from foraging to agro‐pastoral dependence in the lower Azapa Valley. Although oral health indicators point to differences in dietary investment by location, maintenance of a mixed subsistence economy likely sustained a comparative consistency of foodstuffs. Copyright © 2011 John Wiley & Sons, Ltd.
Skeletal Manifestations of Skin Ulcer in the Lower Leg
Authors: Boel L. W. T. , Ortner D. J. 
Published: June 2013

ABSTRACTSkin ulcers of the lower leg are known to cause both destructive and, more commonly, bone‐forming lesions. Typically, bone‐forming lesions in this disorder have clearly defined margins although there may be extensive reactive bone formation involving much or all of the adjacent diaphysis. These lesions are best described in patients from tropical areas, and in these environmental contexts, these are known as tropical ulcers, but leg ulcers can be caused by a variety of diseases and conditions, of which vascular insufficiency plays an important role among the elderly. The lesions are important clinically because of the disability associated with the ulcer and because of complications that can develop including osteomyelitis and cancer. In most cases, the bone lesions caused by ulcer are easily diagnosed in archaeological human skeletal remains and provide some insight into the prevalence of this disorder in antiquity.In this paper, we review the gross and radiological manifestations of bone lesions resulting from overlying skin ulcer in tibiae of 13 cases including archaeological and modern medically documented skeletons. In two of the cases, there is medical documentation regarding the presence of a chronic ulcer on the lower leg. The objectives of this paper were to explore the diversity of bone lesions associated with ulcers of the tibia and to provide an improved basis for the diagnosis of this disorder in human skeletal remains. Copyright © 2011 John Wiley & Sons, Ltd.
Podocyte loss involves MDM2‐driven mitotic catastrophe
Authors: Mulay Shrikant R , Thomasova Dana , Ryu Mi , Kulkarni Onkar P , Migliorini Adriana , Bruns Hauke , Gröbmayr Regina , Lazzeri Elena , Lasagni Laura , Liapis Helen , Romagnani Paola , Anders Hans‐Joachim 
Published: June 2013

AbstractPodocyte apoptosis as a pathway of podocyte loss is often suspected but rarely detected. To study podocyte apoptosis versus inflammatory forms of podocyte death in vivo, we targeted murine double minute (MDM)‐2 for three reasons. First, MDM2 inhibits p53‐dependent apoptosis; second, MDM2 facilitates NF‐κB signalling; and third, podocytes show strong MDM2 expression. We hypothesized that blocking MDM2 during glomerular injury may trigger p53‐mediated podocyte apoptosis, proteinuria, and glomerulosclerosis. Unexpectedly, MDM2 blockade in early adriamycin nephropathy of Balb/c mice had the opposite effect and reduced intra‐renal cytokine and chemokine expression, glomerular macrophage and T‐cell counts, and plasma creatinine and blood urea nitrogen levels. In cultured podocytes exposed to adriamycin, MDM2 blockade did not trigger podocyte death but induced G2/M arrest to prevent aberrant nuclear divisions and detachment of dying aneuploid podocytes, a feature of mitotic catastrophe in vitro and in vivo. Consistent with these observations, 12 of 164 consecutive human renal biopsies revealed features of podocyte mitotic catastrophe but only in glomerular disorders with proteinuria. Furthermore, delayed MDM2 blockade reduced plasma creatinine levels, blood urea nitrogen, tubular atrophy, interstitial leukocyte numbers, and cytokine expression as well as interstitial fibrosis. Together, MDM2‐mediated mitotic catastrophe is a previously unrecognized variant of podocyte loss where MDM2 forces podocytes to complete the cell cycle, which in the absence of cytokinesis leads to podocyte aneuploidy, mitotic catastrophe, and loss by detachment. MDM2 blockade with nutlin‐3a could be a novel therapeutic strategy to prevent renal inflammation, podocyte loss, glomerulosclerosis, proteinuria, and progressive kidney disease. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Cationic poly(ester‐phosphoester)s: Facile synthesis and antibacterial properties
Authors: Zhu Weipu , Du Hong , Huang Ying , Sun Shuai , Xu Ning , Ni Huagang , Cai Xia , Li Xiaodong , Shen Zhiquan 
Published: June 2013

ABSTRACTBiodegradable poly(ester‐phosphoester)s bearing multiple chloroethyl groups were synthesized facilely by the ring‐opening copolymerization of 2‐(2‐chloroethoxy)‐2‐oxo‐1,3,2‐dioxaphospholane (CEP) and ε‐caprolactone (CL) in the presence of lanthanum tris(2,6‐di‐tert‐butyl‐4‐methylphenolate)s (La(DBMP)3) as single‐component catalyst under mild conditions. Then the quaternization reaction was carried out between the halide copolymers and a series of N,N‐dimethyl alkylamines to give poly(ester‐phosphoester)s containing ammonium groups with various charge density and alkyl chain length. The antibacterial properties of these cationic poly(esterphosphoester)s were evaluated by OD600 and zone of inhibition methods against gram‐negative (Escherichia coli) and gram‐positive (Staphylococcus aureus) bacteria. Cationic poly(esterphosphoester)s with long alkyl chain on the ammonium groups show excellent antibacterial activity for both gram‐negative and gram‐positive bacteria even with low charge density. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3667–3673
Long range chirality transfer in free radical polymerization of vinylterphenyl monomers bearing chiral alkoxy groups
Authors: Liu Anhua , Zhao Zhiyuan , Wang Rong , Zhang Jie , Wan Xinhua 
Published: June 2013

ABSTRACTTwo series of chiral bulky vinyl aromatics, 2‐(4'‐alkoxyphenyl)‐5‐(4'‐hexyloxyphenyl)styrene (S‐Am (m = 0, 1, 2, 3)/R‐A0) and 2‐(4'‐hexyloxyphenyl)‐5‐(4'‐alkoxyphenyl)styrene (S‐Bm (m = 0, 1, 2, 3)/R‐B0), were synthesized and radically polymerized (where m denotes the carbon number between stereogenic center and ether oxygen atom). The generation and stereomutation of helical structures as well as chirality transfer from the stereogenic center of the side‐group to the polymer backbone during polymerization were investigated by a combination of 1H‐ and 13C‐NMR, polarimetry, circular dichroism spectroscopy, liquid crystal induced circular dichroism, and computer simulation. All the polymers, except S‐B3, display optical rotations and Cotton effects in the UV‐Vis absorption region of terphenyl pendant, which are quite different from the corresponding model compounds and monomers, suggesting the formation of chiral secondary structures, that is, skewed packing of side‐groups and twisting of polymer backbones with a dominant screw sense. The sign of optical rotation changes alternatively and the strength diminishes when m increases from 1 to 3. However, although the stereogenic centers in S‐A0 and S‐B0 are closer to the vinyl group than those in S‐A1 and S‐B1, separately, a weaker chiral induction power is observed. Moreover, optical rotations of polymers derived from S‐A0/R‐A0 and S‐B0/R‐B0 are opposite in sign and increase with annealing time in tetrahydrofuran. These results are in a sharp contrast with our previous findings in similar vinylterphenyl compounds, where ‐COO‐ rather than ‐O‐ links the chiral alkyl tail to the terphenyl group, manifesting a remarkable effect of small structural variation of side‐group on polymer chiroptical properties and complexity of chirality transfer in helix‐sense‐selective polymerization. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3674–3687
Synthesis, self‐assembly and reversible healing of supramolecular perfluoropolyethers
Authors: Li Guoxing , Wie Jeong Jae , Nguyen Ngoc A. , Chung Woo Jin , Kim Eui Tae , Char Kookheon , Mackay Michael E. , Pyun Jeffrey 
Published: June 2013

ABSTRACTThe synthesis and thermomechanical properties of a novel class of self‐healing perfluoropolyethers (PFPEs) is reported. By decoration of 2‐ureido‐4[1H]‐pyrimidone end groups on the termini of low molar mass PFPE, the formation of supramolecular polymers and networks held together via hydrogen bonding associations was achieved. These novel supramolecular polymer materials exhibit a combination of enhanced modulus and elasticity, along with self‐healing properties, where rapid self‐healing time was demonstrated using dynamic rheological measurements. These types of supramolecular PFPEs are anticipated to be useful for a number of emerging areas in lubrication. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3598–3606
Polyaddition of bifunctional 1,3‐benzoxazine and 2‐methylresorcinol
Authors: Oie Hiroaki , Mori Atsushi , Sudo Atsushi , Endo Takeshi 
Published: June 2013

ABSTRACT:A polyaddition system consisted of a bifunctional N‐n‐propyl benzoxazine and 2‐methylresorcinol (MR) that proceeds at ambient temperature has been developed. In this system, the aromatic ring of MR acted as a bifunctional monomer, reacting with a two equivalent amount of benzoxazine moieties via their ring‐opening reaction. The polyaddition gave the corresponding linear polymer bearing phenolic moieties bridged by Mannich‐type linkage in the main chain. The linear polymer had a high glass transition temperature, which was comparable to that of the linear polybenzoxazine synthesized by the ring‐opening polymerization of a monofunctional N‐n‐propyl benzoxazine. The employment of a bifunctional N‐allyl benzoxazine in the polyaddition system resulted in the formation of the corresponding polymer with allyl pendants, which exhibited improved heat resistance due to its thermally induced crosslinking reaction. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3867–3872
Camptothecin‐induced expression of programmed cell death gene 11 in Spodoptera litura
Authors: Gong Liang , Wang Huidong , Huang Jingfei , Hu Meiying , Hu Zheng , Zhong Guohua 
Published: June 2013

AbstractBACKGROUNDCamptothecin, one of the main active components of extract from the bark of the Chinese camptotheca tree, has been reported as a potent insecticide against various insect species. However, the mechanism of action of camptothecin as a botanical pesticide is not completely understood.RESULTSIn this study, the full‐length cDNA (GeneBank number JF681972) of Spodoptera litura programmed cell death protein 11 (pcdp 11) isoform 1 was cloned, sequenced and characterised. Quantitative real‐time PCR (qRT‐PCR) data showed that pcdp 11 was differentially expressed during the developmental stages, with significantly high expression during the transition from egg to larva and larva to pupa. Furthermore, pcdp 11 was upregulated in a time‐dependent manner in SL‐1 cells after treatment with 1.2 µg mL−1 of camptothecin. The induced expression profile of pcdp 11 in the larval midgut after feeding camptothecin was visualised by fluorescence in situ hybridisation (FISH) and further quantified by qRT‐PCR. Apoptosis in camptothecin‐treated larval midguts was confirmed using terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) staining.CONCLUSIONThe results reveal a clear functional link between pcdp 11 expression and camptothecin‐induced apoptosis, and prove that camptothecin exhibits strong toxicity towards S. litura by inducing midgut epithelial cell apoptosis. © 2013 Society of Chemical Industry
Expectation value based cluster expansion
Authors: Leymann Heinrich A. M. , Foerster Alexander , Wiersig Jan 
Published: June 2013

AbstractWe outline a new formulation of the cluster expansion to derive equations of motion for open quantum systems. Our method uses expectation values instead of correlation functions. The algebraic effort to derive the equations is reduced and the approach is more intuitive.We demonstrate the efficiency of our method by applying it to the damped Jaynes‐Cummings model. This model is a good starting point to investigate quantum dot based laser systems. Further we will examine the convergence properties of the cluster expansion for various orders. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Analytical solutions for electronic states in three‐dimensional semiconductor quantum rings
Authors: Vänskä O. , Kira M. , Koch S. W. , Tittonen I. 
Published: June 2013

AbstractWe study single‐particle electronic states of a threedimensional semiconductor quantum ring. Starting from the envelope‐function theory, we formulate a fully analytical model for single‐particle wave functions and confinement energies of charge carriers.The approximative harmonic‐oscillator model is found to be in excellent agreement with numerical results. The model is a powerful tool in practical calculations when there is a need to go beyond single particle properties to more demanding many‐body effects. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Maximum likelihood estimation of gamma parameters for coarsely binned and truncated raindrop size data
Authors: Johnson Roger W. , Kliche Donna V. , Smith Paul L. 
Published: June 2013

AbstractThe gamma family of probability densities has recently been used to model raindrop size. However, the traditional approach of using the method of moments to estimate the gamma distribution parameters is known to be biased and can have substantial errors. A recently developed approach combining moment information and a weighted least‐squares analysis generally produces substantially better results. Other procedures superior to the method of moments approach include maximum likelihood. In particular, maximum likelihood estimates have been shown to outperform method of moments estimators, both for the case in which the full range of drop sizes are observed and for the case in which small drop sizes fail to be observed because of the inability of disdrometers to record observations below a threshold.The foregoing comments on maximum likelihood concern the situation in which drop sizes are measured on a continuous scale. In this work we consider drop sizes from gamma distributions which are classified into broad size bins, as would be the case with data obtained from many disdrometers; this requires some modification of the maximum likelihood procedure. We also allow for the possibility of drop sizes below a threshold, or above another threshold, not being observed. Maximum likelihood performance in this case is investigated through simulation of volume sampling from gamma distributions with known parameters. We compare the performance of the maximum likelihood estimates with those of method of moments (only a truncated‐data version is viable) and the recently developed weighted least‐squares procedure, and also apply the three estimation procedures to some experimental data. Since the experimental data are surface data, we indicate how drop fall velocity may be incorporated to obtain parameters for the volume distributions from the surface data.
Formal specification and analysis of functional properties of graph rewriting‐based model transformation
Authors: Asztalos Márk , Lengyel László , Levendovszky Tihamér 
Published: June 2013

SUMMARYModel processing programs are regularly used when working with models or synthetizing the code from them; therefore, their verification has become an essential component of constructing reliable software in model‐based software engineering. Models are usually formalized and visualized as graphs; therefore, model processing programs based on algebraic graph rewriting systems—such programs are called model transformations—are often applied, and their verification has become an important research area. The goal of our research is to support offline transformation analysis by automated methods, where offline means that only the definition of the program itself, the language definitions of its source and target models are used during the analysis. Therefore, the results are independent from concrete source models, and the analysis needs to be performed only once. Based on previous work, this paper provides the synthesis and of a set of individual components and improves them to provide a complete verification solution: (i) a language is introduced to specify the properties to be verified; (ii) a formalism to describe model transformations in a declarative way; and (iii) automated algorithms that can analyse the declarative transformations as well as the properties expressed by the language. Besides its theoretical basis, the implementation of a verification framework is presented, and its operation is illustrated on a case study. Although the formal verification of model transformation properties is algorithmically undecidable in general, our goal is to provide a practically usable, scoped framework that can largely facilitate the manual verification of model transformations. Copyright © 2013 John Wiley & Sons, Ltd.
3Mg(OH)2·MgSO4·8H2O: A Metastable Phase in the System Mg(OH)2‐MgSO4‐H2O
Authors: Dinnebier Robert E. , Pannach Melanie , Freyer Daniela 
Published: June 2013

AbstractIn the course of investigations relating to magnesia oxysulfate cement the basic magnesium salt hydrate 3Mg(OH)2·MgSO4·8H2O (3–1–8 phase) was found as a metastable phase in the system Mg(OH)2‐MgSO4‐H2O at room temperature (the 5–1–2 phase is the stable phase) and was characterized by thermal analysis, Raman spectroscopy, and X‐ray powder diffraction. The complex crystal structure of the 3–1–8 phase was determined from high resolution laboratory X‐ray powder diffraction data [space group C2/c, Z = 4, a = 7.8956(1) Å, b = 9.8302(2) Å, c = 20.1769(2) Å, β = 96.2147(16)°, and V = 1556.84(4) Å3]. In the crystal structure of the 3–1–8 phase, parallel double chains of edge‐linked distorted Mg(OH2)2(OH)4 octahedra run along [–110] and [110] direction forming a pattern of crossed rods. Isolated SO4 tetrahedra and interstitial water molecules separate the stacks of parallel double chains.
Synthesis and Structures of Two Dinuclear Transition Metal Complexes and Their Catalytic Applications in Hydrogenation of Ketones
Authors: He Jianhua , Zeng Mulan , Cheng Haiyan , Chen Zilu , Liang Fupei 
Published: June 2013

AbstractThe complexes [Ni2(L)2]2·H2O (1) and [Cu2(L)2(H2O)]·2CH3OH (2) were prepared by reaction of the chiral Schiff base ligand N‐[(1R,2S)‐2‐hydroxy‐1,2‐diphenyl]‐acetylacetonimine (H2L) with NiII and CuII ions, respectively, aiming to develop economically and environmentally‐friendly catalysts for the hydrogenation of ketones. They have a dinuclear skeleton with axial vacant sites. The catalytic effects of the two complexes for hydrogenation of ketones were tested using dihydrogen gas as hydrogen source. They present some catalytic effects in hydrogenation of acetophenone, which has a dependence on the temperature and base used in these reactions. However, no apparent catalytic effects were found for the two complexes in hydrogenation of 4‐nitroacetophenone and 4‐methylacetophenone. Although the catalytic conversion in these hydrogenation reactions is low, they do represent a kind of cheap and environmentally‐friendly hydrogenation catalyst.