bluuebunny/crossref_metadata_2025_split huggingface dataset:
Surface Diels–Alder Reactions as an Effective Method to Synthesize Functional Carbon Materials
Authors: Kaper Helena , Grandjean Agnes , Weidenthaler Claudia , Schüth Ferdi , Goettmann Frédéric 
Published: February 2012

AbstractThe post‐synthesis chemical modification of various porous carbon materials with unsaturated organic compounds is reported. By this method, amine, alcohol, carboxylate, and sulfonic acid functional groups can be easily incorporated into the materials. Different carbonaceous materials with surface areas ranging from 240 to 1500 m2 g−1 and pore sizes between 3.0 and 7.0 nm have been studied. The resulting materials were analyzed by elemental analysis, nitrogen sorption, FTIR spectroscopy, zeta‐potential measurements, thermogravimetric analysis, photoelectron spectroscopy, and small‐angle X‐ray scattering. These analyses indicated that the degree of functionalization is dependent on the nature of the dienophile (reactivity, steric hindrance) and the porosity of the carbon material. As possible applications, the functionalized carbonaceous materials were studied as catalysts in the Knoevenagel reaction and as adsorbents for Pb2+ from aqueous solution.
A Simple Polyoxometallate for Selective Oxidation of Benzyl Alcohol to Benzaldehyde with Hydrogen Peroxide
Authors: Tian Wei , Hou Yang , Wang Xiaoguang , Lu Bin , Zhao Jingxiang , Cai Qinghai 
Published: February 2012

AbstractA series of Keggin‐type polyoxometallates, M3(PW12O40)2 [M=Ni, Zn, Co, Mn, Cu], FePW12O40, Ni3(PMo12O40)2 and Ni2SiW12O40, were prepared and used as catalysts for selective oxidation of benzyl alcohol into benzaldehyde with H2O2 as an oxidant under solvent‐free condition. Ni3(PW12O40)2·26H2O afforded high catalytic activity with TON of 550.6 mol/(mol cat.) and 87.3% selectivity. However, this catalyst can be easily recovered and reused.
Synthesis and Bioactivity of Substituted Benzoylguanidine Derivatives as Potent Na+/H+ Exchanger Inhibitors
Authors: Jin Ning , Yang Yun , Xu Wenting , Yang Xiaozhi , Gong Guoqing , Xu Yungen 
Published: February 2012

AbstractA novel series of substituted benzoylguanidine derivatives were designed and synthesized in order to evaluate their NHE1 inhibitory activity. Most of them were found to inhibit NHE1‐mediated platelet swelling in a concentration‐dependent manner, and eight compounds showed more potent NHE1 inhibitory activity than Cariporide. Compound 6f with an IC50 value of 1.08×10−10 mol·L−1, was 39 times more potent than lead compound CPU‐X‐050420 in vitro tests.
An Efficient Four‐component Synthesis of Spiro[indoline‐pyrazolo[4′,3′:5,6]pyrido[2,3‐d]pyrimidine]triones
Authors: Ghahremanzadeh Ramin , Moghaddam Mojtaba Mirhosseini , Bazgir Ayoob , Akhondi Mohammad Mehdic 
Published: February 2012

AbstractA four‐component reaction in the presence of Alum [KAl(SO4)2·12H2O] as an inexpensive and reusable catalyst using the ionic liquid as an effective green reaction media is reported.
Preparation of Ultrafine TATB and the Technology for Crystal Morphology Control
Authors: Yang Li , Ren Xiaoting , Li Tiecheng , Wang Shiwei , Zhang Tonglai 
Published: February 2012

AbstractThe ultrafine 1,3,5‐triamino‐2,4,6‐trinitrobenzene (TATB) has been prepared by using solvent and non‐solvent method, and the influencing factors in close relationship with the grain size and crystal morphology control such as categories and dosage of surfactants, volume ratio of solvent to non‐solvent have also been considered in this paper. It showed that these factors had remarkable effect on the crystal morphology, particle size and agglomeration during the crystallization process. By using 0.095% (mass percentage) ionic surfactant (S) as the additive and using spray‐drops feeding device as the dropping equipment, 1.06 g TATB raw materials have been refined into free‐running ellipsoid and spherical TATB grains with the grain size from 30 to 50 nm. By using 0.014% (mass percentage) non‐ionic surfactant (P) as the additive, spherical TATB grains with the particle diameter of 50 nm and with narrow particle‐size distribution have also been obtained. It was shown by the characterizations that the ultrafine particle of TATB had better heat resisting evenness and its 5 seconds ignition point is advanced by 7.5 K.
Selective and Sensitive Fluorescent Chemosensors for Cu2+ Ion Based upon Bis‐1,8‐naphthalimide Dyads
Authors: Dai Huiling , Xu Hui 
Published: February 2012

AbstractA series of new fluorescent chemosensors 5a–5e, composed of two aminonaphthalimide fluorophores and 2,6‐bis((N‐aminoalkyl)aminocarboxy)pyridines, were prepared, characterized, and their fluorescent properties towards heavy and transition metal (HTM) ions were investigated. Chemosensors 5c–5e exhibited high selectivity and sensitivity for Cu2+ ion over other HTM ions with fluorescent quenching (green to colourless). It clearly demonstrated that the length of the linkers (diamines) between the aminonaphthalimides and 2,6‐dicarboxypyridine of 5a–5e was very important for their sensitivity and selectivity for Cu2+ ion over other HTM ions.
Potassium tert‐Butoxide Catalyzed Synthesis and Characterization of Novel 3‐Aryl‐3‐(phenylthio)‐1‐(thiophen‐3‐yl)propan‐1‐one Derivatives
Authors: Budak Yakup 
Published: February 2012

AbstractA series of thiophenyl‐containing 3‐thiophene derivatives (4a–4i) were prepared via the reaction of chalcone‐analogua compounds (3a–3i) and thiophenol in the presence of catalytic amount of KOBu‐t in CH2Cl2 with moderate to high yields. The mechanistic pathway of the reaction was explained by the Michael‐type addition of thiophenol to chalcone derivatives (3a–3i).
Electrochemical Property of Manganese Oxide Nanobelt Bundles with Layered Structure
Authors: Kang Liping , Jiang Yishu , Tang Xiuhua , Yang Mingyang , Liu Zonghuai 
Published: February 2012

AbstractOne‐dimensional manganese oxide nanobelt bundles with birnessite‐type structure have been synthesized by a hydrothermal process in a NaOH solution employing K‐type layered manganese oxide as a precursor. The obtained manganese oxide nanobelt bundles exhibit excellent discharge properties and cycle stability. The initial capacity is 376 mAh·g−1 and the reversible capacity of 243 mAh·g−1 is maintained after the 50th cycle at a current density of 20 mA·g−1. Meanwhile, the manganese oxide nanobelt bundles show an excellent cycle performance even if at relative high current density.
Asymmetric Synthesis of All Four Isomers of an Unusual Heterocycle‐Containing Amino Acid: 2‐Amino‐3‐furan‐2‐yl‐pentanoic Acid
Authors: Nie Lei , Yang Rui , Zhang Conghai , Yin Haichuan , Yan Shengjiao , Lin Jun 
Published: February 2012

AbstractAll four isomers of a novel β‐branched unusual amino acid were designed and synthesized with high stereoselectivity (>90% de) and in 33% –44% overall yields by the use of 4(R/S)‐5,5‐dimethyl‐4‐phenyl‐oxazolidin‐2‐one as the chiral auxiliary via asymmetric 1,4‐Michael addition, direct or indirect azidation, hydrolysis and hydrogenation reactions.
Fluorescence Properties of Carba Nicotinamide Adenine Dinucleotide for Glucose Sensing
Authors: von Ketteler Alexa , Herten Dirk‐Peter , Petrich Wolfgang 
Published: February 2012

AbstractCarba nicotinamide adenine dinucleotide (cNAD) may serve as a stable cofactor for the enzyme‐based detection of glucose. Many characteristics of cNAD and its reduced form cNADH resemble those of NAD and NADH, respectively. The fluorescence lifetimes of cNADH are determined to be 0.32(2) ns and 0.66(3) ns compared to 0.28(2) ns and 0.60(3) ns for NADH, and the temperature dependence of these lifetimes hints towards identical processes for quenching. The maximum emission occurs at 464 nm for both cNADH and NADH and absorbance maxima are found at 360 nm and 340 nm, respectively. In contrast to previous suggestions the respective maximum extinction coefficient of cNADH equals that of NADH and amounts to 6.2(2) mM−1 cm−1. When changing from NADH to cNADH we observe a ∼50 % increase in quantum efficiency, which—together with the larger excitation wavelength and the higher stability—should make cNAD a well suited alternative as coenzyme for robust glucose detection.
Ultrasound and Microstructures—A Promising Combination?
Authors: Hübner S. , Kressirer S. , Kralisch D. , Bludszuweit‐Philipp C. , Lukow K. , Jänich I. , Schilling A. , Hieronymus H. , Liebner C. , Jähnisch K. 
Published: February 2012

AbstractShort diffusion paths and high specific interfacial areas in microstructured devices can increase mass transfer rates and thus accelerate multiphase reactions. This effect can be intensified by the application of ultrasound. Herein, we report on the design and testing of a novel versatile setup for a continuous ultrasound‐supported multiphase process in microstructured devices on a preparative scale. The ultrasonic energy is introduced indirectly into the microstructured device through pressurized water as transfer medium. First, we monitored the influence of ultrasound on the slug flow of a liquid/liquid two‐phase system in a channel with a high‐speed camera. To quantify the influence of ultrasound, the hydrolysis of p‐nitrophenyl acetate was utilized as a model reaction. Microstructured devices with varying channel diameter, shape, and material were applied with and without ultrasonication at flow rates in the mL min−1 range. The continuous procedures were then compared and evaluated by performing a simplified life cycle assessment.
In vivo visualization of the lymphatic vessels in pFLT4‐EGFP transgenic medaka
Authors: Deguchi Tomonori , Fujimori Kazuhiro E. , Kawasaki Takashi , Maruyama Kouichi , Yuba Shunsuke 
Published: February 2012

AbstractFeline McDonough Sarcoma (FMS)‐like tyrosine kinase 4 (FLT4) is a marker for lymphatic vessels and some high endothelial venules in human adult tissues. We generated a transgenic medaka fish in which the lymphatic vessels and some blood vessels are visible in vivo by transferring the promoter of medaka flt4 driving the expression of enhanced green fluorescent protein (EGFP) using a see‐through medaka line. To do this, we identified and cloned medaka flt4 and generated a construct in which the promoter was the 4‐kb region upstream of the translation initiation site. The fluorescent signal of EGFP could be observed with little background, and the expression pattern correlated well with that of flt4 determined by whole‐mount RNA in situ hybridization. Because a see‐through medaka line is transparent until adult, the model is useful for visualizing the lymphatic vessels not only in embryo and fry but also in adult. This model will be a useful tool for analyzing lymphatic development. genesis 50:625–634, 2012. © 2012 Wiley Periodicals, Inc.
Population‐based resequencing revealed an ancestral winter group of cultivated flax: implication for flax domestication processes
Authors: Fu Yong‐Bi 
Published: February 2012

AbstractCultivated flax (Linum usitatissimum L.) is the earliest oil and fiber crop and its early domestication history may involve multiple events of domestication for oil, fiber, capsular indehiscence, and winter hardiness. Genetic studies have demonstrated that winter cultivated flax is closely related to oil and fiber cultivated flax and shows little relatedness to its progenitor, pale flax (L. bienne Mill.), but winter hardiness is one major characteristic of pale flax. Here, we assessed the genetic relationships of 48 Linum samples representing pale flax and four trait‐specific groups of cultivated flax (dehiscent, fiber, oil, and winter) through population‐based resequencing at 24 genomic regions, and revealed a winter group of cultivated flax that displayed close relatedness to the pale flax samples. Overall, the cultivated flax showed a 27% reduction of nucleotide diversity when compared with the pale flax. Recombination frequently occurred at these sampled genomic regions, but the signal of selection and bottleneck was relatively weak. These findings provide some insight into the impact and processes of flax domestication and are significant for expanding our knowledge about early flax domestication, particularly for winter hardiness.
Cholesterol versus other sterols: How do they compare as physiological regulators of cholesterol homeostasis?
Authors: Brown Andrew J. 
Published: February 2012

AbstractThere is a growing body of work indicating that maintaining cholesterol homeostasis involves oxysterol‐derivatives and sterol precursors of cholesterol. Their importance relative to cholesterol itself is a contentious area, which is difficult to address experimentally. In this review, the molecular basis of cholesterol homeostasis is briefly described, some of the major putative sterol regulators introduced, and the evidence that they may indeed serve as physiological regulators is discussed, along with caveats of this research. This review will also briefly address some recent literature ascribing physiological roles of non‐cholesterol sterols beyond cholesterol metabolism.
On the treatment of transient area variation in 1D discontinuous Galerkin simulations of train‐induced pressure waves in tunnels
Authors: Biotto C. , Proverbio A. , Ajewole O. , Waterson N. P. , Peiró J. 
Published: February 2012

SUMMARYTo simulate the pressure wave generated by a train travelling through a tunnel, we implement a discontinuous Galerkin (DG) method for the solution of the one‐dimensional equations of variable area flow. This formulation uses a spatial discretisation via Legendre polynomials of arbitrary degree, and the resulting semi‐discrete system is integrated using an explicit Runge–Kutta scheme. A simulation of subsonic steady flow in a nozzle shows that the scheme produces stable solutions, without the need for artificial dissipation, and that its performance is optimal for polynomial degrees between 5 and 7. However, when dealing with an unsteady area, we report the presence of numerical oscillations that are not due to the steep pressure fronts in the flow but rather to the projection of a moving area, with piecewise continuous derivatives onto a fixed grid. We propose a reformulation of the DG method to eliminate these oscillations that, put in simple terms, amount to splitting the integrals where the derivatives of the cross‐sectional area are discontinuous into subintegrals where they are continuous. The resulting method does not exhibit oscillations, and it is applied here to two practical cases involving train‐induced pressure waves in a tunnel. The first application is a validation of the DG method through comparison of its computational results with pressure data measured during transit at the Patchway tunnel near Bristol (UK). The second application is a study of the influence of the nose shape and length on the pressure wave gradients responsible for sonic boom at tunnel exit portals to show that the proposed modification is able to deal with realistic train shapes. Copyright © 2012 John Wiley & Sons, Ltd.
Localized DNA cleavage secondary to genotoxic exposure adjacent to an Alu inverted repeat
Authors: Ho Bay , Baker Pamela M. , Singh Sheetal , Shih Shyh‐Jen , Vaughan Andrew T. 
Published: February 2012

AbstractRadiation is a potent inducer of DNA damage leading to both random DNA loss and mutation. As part of a study focused on the mechanism whereby cells undergo loss of heterozygosity (LOH), a region of common LOH telomeric termination at 11q24 was observed in clones of H292 mucoepidermoid cells established after irradiation (IR). A 10‐kbp region including the telomeric extent of LOH termination was analyzed after IR using six sets of ligation‐mediated polymerase chain reaction (PCR) primers to detect the presence of DNA breaks. A cluster of DNA breaks was detected that closely mapped to the telomeric extent of LOH and which were observed up to 8 hr after IR. Repeating the experiment in the presence of the inhibitor of apoptosis, zVAD.fmk, did not change the location or amount of cleavage. A similar distribution of breaks was also seen in the MCF‐10A breast cancer cell line after IR. Further inspection of the involved region showed that 22/32 and 7/7 DNA breaks found in H292 and MCF‐10A cells, respectively, were located either in or immediately adjacent to an AluSx1 sequence, itself ∼1 kbp 5′ to an AluSq2 that was in an inverted orientation to the AluSx1. The region between the inverted Alu repeats was notable for both DNAse hypersensitivity and an open chromatin conformation inferred from histone modification data. These factors may contribute to genomic instability at this location. © 2012 Wiley Periodicals, Inc.
Segmental chromosome aberrations converge on overexpression of mitotic spindle regulatory genes in high‐risk neuroblastoma
Authors: Ooi Wen Fong , Re Angela , Sidarovich Viktoryia , Canella Valentina , Arseni Natalia , Adami Valentina , Guarguaglini Giulia , Giubettini Maria , Scaruffi Paola , Stigliani Sara , Lavia Patrizia , Tonini Gian Paolo , Quattrone Alessandro 
Published: February 2012

AbstractIntegration of genome‐wide profiles of DNA copy number alterations (CNAs) and gene expression variations (GEVs) could provide combined power to the identification of driver genes and gene networks in tumors. Here we merge matched genome and transcriptome microarray analyses from neuroblastoma samples to derive correlation patterns of CNAs and GEVs, irrespective of their genomic location. Neuroblastoma correlation patterns are strongly asymmetrical, being on average 10 CNAs linked to 1 GEV, and show the widespread prevalence of long range covariance. Functional enrichment and network analysis of the genes covarying with CNAs consistently point to a major cell function, the regulation of mitotic spindle assembly. Moreover, elevated expression of 14 key genes promoting this function is strongly associated to high‐risk neuroblastomas with 1p loss and MYCN amplification in a set of 410 tumor samples (P < 0.00001). Independent CNA/GEV profiling on neuroblastoma cell lines shows that increased levels of expression of these genes are linked to 1p loss. By this approach, we reveal a convergence of clustered neuroblastoma CNAs toward increased expression of a group of prognostic and functionally cooperating genes. We therefore propose gain of function of the spindle assembly machinery as a lesion potentially offering new targets for therapy of high‐risk neuroblastoma. © 2012 Wiley Periodicals, Inc.
Disease‐associated patterns of disomic chromosomes in hyperhaploid neoplasms
Authors: Mandahl Nils , Johansson Bertil , Mertens Fredrik , Mitelman Felix 
Published: February 2012

AbstractThe chromosome number of human tumors varies widely, from near‐haploidy to more than decaploidy. Overt hyperhaploid (24–34 chromosomes) tumors constitute a small minority (0.2–0.3% of cytogenetically investigated lesions), but occur in many different disease entities. In these karyotypes, most chromosomes are present in one copy; one or a few chromosomes are disomic. Published reports on 141 strictly hyperhaploid tumors, supplemented with nine previously unpublished cases, were used for evaluating the pattern of disomic chromosomes. Only one tumor type, acute lymphoblastic leukemia (ALL), was sufficiently common (n = 75) to allow proper evaluation; other neoplasms were lumped together in as reasonably logical groups as possible, including 10 myeloid leukemias (ML), nine plasma cell neoplasms (PCN), 13 chondrosarcomas (CS), 11 soft tissue tumors (STT), nine adeno‐ or squamous cell carcinomas (ASC), and eight tumors of the nervous system (TNS); the remaining 15 tumors could not be grouped. It was evident that the pattern of disomies is nonrandom. Moreover, unique signatures for each tumor group were detected. Among ALL, most disomies were independent of age and gender, except for disomy 10, which was overrepresented in females. Chromosome 21 was invariably disomic, whereas chromosome 17 was always monosomic. The most frequent disomies were two gonosomes in ML, chromosomes 7, 9, 11, 3, 18, and 19 in PCN, 7, 5, 20, 19, and 21 in CS, 20 in STT, 7 in ASC, and 1, 7, and 9 in TNS. Chromosome 1 was often partially disomic, due to unbalanced structural rearrangements, with segment 1q21–31 in common. Doubling of the hyperhaploid clone was found in at least one‐third of the cases, apart from in ML where only one of 10 cases showed chromosome doubling. The present findings indicate that retention of disomy for some chromosomes is pathogenetically important and that the chromosome(s) maintained in two copies is related to cell type or histological context. © 2012 Wiley Periodicals, Inc.
Establishment of myelinating schwann cells and barrier integrity between central and peripheral nervous systems depend on Sox10
Authors: Fröb Franziska , Bremer Magdalena , Finzsch Markus , Kichko Tatjana , Reeh Peter , Tamm Ernst R. , Charnay Patrick , Wegner Michael 
Published: February 2012

AbstractThe transcription factor Sox10 is expressed throughout Schwann cell development and has already been shown to be essential for specification and for the identity and further development of immature Schwann cells. Here, we show that Sox10 is also required in Schwann cells for establishing the myelinating state. This is concluded from the fact that a peripheral neuropathy develops in mice in which Sox10 is deleted by a Cre recombinase whose expression is under control of Krox20 regulatory elements. This neuropathy is characterized by altered marker gene expression along the peripheral nerve, decreased conductivity, and severe persistent hypomyelination. As the Cre recombinase is additionally active in boundary cap cells, we also analyzed the role of Sox10 during embryogenesis in establishment and maintenance of the boundary between central and peripheral nervous systems. Sox10 deletion did not affect establishment or survival of boundary cap cells but appeared to compromise barrier function as cells expressing oligodendrocyte and astrocyte markers were no longer restricted to the central nervous system, and instead found in peripheral nerves. We infer that in addition to its many roles in Schwann cells, Sox10 is also important for the integrity of the boundary between central and peripheral nervous systems. © 2012 Wiley Periodicals, Inc.
What predicts whether caregivers of people with dementia find meaning in their role?
Authors: Quinn Catherine , Clare Linda , Woods Robert T. 
Published: February 2012

BackgroundInformal dementia caregiving has traditionally been perceived as an extremely stressful process; however, more recent research has started to focus on the positive aspects of providing care. Studies indicate that caregivers who derive something positive out of caregiving have better well‐being. However, there has been little exploration of the factors linked to caregivers identifying positive aspects of providing care. The aim of the current study was to explore the predictors of finding meaning in caregiving.MethodsThis was a cross‐sectional questionnaire study in which the respondents were 447 caregivers of people with dementia who were in receipt of a specialist nursing service. The questionnaire contained measures of meaning, relationship quality, caregivers' motivations to provide care, role captivity and caregiving competence.ResultsCorrelational analyses showed that higher meaning was associated with being a spousal caregiver, providing greater hours of care, higher religiosity, a better pre‐caregiving and current relationship quality, higher competence, lower role captivity, higher intrinsic motivations and higher extrinsic motivations. Hierarchical regression analyses indicated that variance in finding meaning was significantly predicted by high religiosity, high competence, high intrinsic motivations and low role captivity.ConclusionFrom these findings, it is recommended that interventions should help caregivers focus on positive aspects of providing care and enhance their feelings of competence. Copyright © 2012 John Wiley & Sons, Ltd.