bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Arm‐First Approach to Cleavable Mikto‐Arm Star Polymers by RAFT Polymerization
Authors: Wei Xiaohu , Moad Graeme , Muir Benjamin W. , Rizzardo Ezio , Rosselgong Julien , Yang Wantai , Thang San H. 
Published: February 2014

Redox‐cleavable mikto‐arm star polymers are prepared by an “arm‐first” approach involving copolymerization of a dimethacrylate mediated by a mixture of macroRAFT agents. Thus, RAFT copolymerization of the monomers BMA, DMAEMA, and OEGMA, with the disulfide dimethacrylate cross‐linker (DSDMA), bis(2‐methacryloyl)oxyethyl disulfide, mediated by a 1:1:1 mixture of three macroRAFT agents with markedly different properties [hydrophilic, poly[oligo(ethylene glycol) methacrylate]—P(OEGMA)8–9; cationizable, poly[2‐(dimethylamino)ethyl methacrylate]—P(DMAEMA); hydrophobic, poly(n‐butyl methacrylate)—P(BMA)] provides low dispersity mikto‐arm star polymers. Good control (Đ < 1.3) is observed for the target P(DMAEMA)/P(OEGMA)/P(BMA) (3:3:1) mikto‐arm star, a double hydrophilic P(DMAEMA)/P(OEGMA) (3:3) mikto‐arm star and a hydrophobic P(BMA) homo‐arm star. However, Đ for the target mikto‐arm stars increases with an increase in either the ratio [DSDMA]:[total macroRAFT] or the fraction of hydrophobic P(BMA) macroRAFT agent. The quaternized mikto‐arm star in dilute aqueous solution shows a monomodal particle size distribution and an average size of ≈145 nm.
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Investigation of impact characteristics of tempered vehicle and vessel glasses
Authors: Gürsel K. T. , Özgül F. 
Published: February 2014

Glass is widely used at various engineering applications, especially in vehicle and vessel industry due to the reasons such as transparency, hardness at the room temperature and its strength against impact. One of the processes to be applied to glass is tempering. This process is applied to glass with the aim of providing 2–5 times more impact resistance. Additionally, if tempered glass is fractured it goes to pieces without sharp edges. These pieces are too small to injure people around them. Thus, nowadays side and rear glasses of vehicles and vessels are tempered glasses.In this study, tempered and untempered vehicle glasses were tested by using Instron Dynatup 9250 HV Impact Apparatus in the Mechanical Engineering Department of Pamukkale University, impact was applied to 145 samples with an average of 5.3 (771) times and their impact strength values were determined.In the first stage of this study, magnitudes of impact energies causing damages at tempered and untempered vehicle and vessel glasses with a thickness of 4 mm and 6 mm at +20 °C, were determined. In the second stage, impact experiments were performed at the environment temperatures of –20 °C and +40 °C apart from the room temperature, because the glasses to be produced will be used in different climate zones.In this way, a useful source of knowledge, especially for developing tempered vehicle and vessel glasses, will be constituted by determining the impact strength characteristics of these glasses.
Heterogeneity in primary dystonia: Lessons from THAP1, GNAL, and TOR1A in Amish‐Mennonites
Authors: Saunders‐Pullman Rachel , Fuchs Tania , San Luciano Marta , Raymond Deborah , Brashear Alison , Ortega Robert , Deik Andres , Ozelius Laurie J. , Bressman Susan B. 
Published: February 2014

ABSTRACTA founder mutation in the Thanatos‐associated (THAP) domain containing, apoptosis associated protein 1 (THAP1) gene causing primary dystonia was originally described in the Amish‐Mennonites. However, there may be both genotypic and phenotypic heterogeneity of dystonia in this population that may also inform studies in other ethnic groups. Genotyping for THAP1 and for guanine nucleotide binding protein (G protein), α‐activating activity polypeptide, olfactory type (GNAL) mutations and genotype‐phenotype comparisons were performed for 76 individuals of Amish‐Mennonites heritage with primary dystonia. Twenty‐seven individuals had mutations in THAP1—most with the founder indel mutation—but two had different THAP1 mutations, 8 had mutations in GNAL, and 1 had a de novo GAG deletion in torsin 1A (TOR1A) (dystonia 1 [DYT1]). In the primary analysis comparing THAP1 carriers versus all non‐THAP1, non‐GNAL, non‐TOR1A individuals, age at onset was lower in THAP1 carriers (mean age ± standard deviation, 15.5 ± 9.2 years [range, 5‐38 years] vs. 39.2 ± 17.7 years [range, 1‐70 years]; P < 0.001), and THAP1 carriers were more likely to have onset of dystonia in an arm (44.4% vs. 15.0%; P = 0.02) and to have arm involvement (88.9% vs. 22.5%; P < 0.01), leg involvement (51.9% vs. 10.0%; P = 0.01), and jaw/tongue involvement (33.3% vs. 7.5%; P = 0.02) involvement at their final examination. Carriers were less likely to have dystonia restricted to a single site (11.11% in carriers vs. 65.9% in noncarriers; P < 0.01) and were less likely to have dystonia onset in cervical regions (25.9% of THAP1 carriers vs. 52.5% of noncarriers; P = 0.04). Primary dystonia in the Amish‐Mennonites is genetically diverse and includes not only the THAP1 indel founder mutation but also different mutations in THAP1 and GNAL as well as the TOR1A GAG deletion. Phenotype, particularly age at onset combined with final distribution, may be highly specific for the genetic etiology. © 2014 International Parkinson and Movement Disorder Society
Limbic substrates of the effects of neuropeptide Y on intake of and motivation for palatable food
Authors: Pandit Rahul , Luijendijk Mieneke C.M. , Vanderschuren Louk J.M.J. , la Fleur Susanne E. , Adan Roger A.H. 
Published: February 2014

ObjectiveNeuropeptide Y (NPY), given centrally augments food intake and the motivation to work for palatable food. Here, the brain regions were identified through which NPY increases food intake and motivation.MethodsNPY was infused into three brain regions implicated in food intake and motivation: the lateral hypothalamus (LH), nucleus accumbens shell (NAc), and ventral tegmental area (VTA). Motivation for sucrose was assessed using a progressive‐ratio schedule of reinforcement in which the effort to obtain successive rewards increased incrementally. To disentangle the effects of NPY on motivation for palatable food from food consumption, free‐feeding experiments were performed in which animals had ad libitum access to sucrose pellets.ResultsInfusion of NPY into either VTA or NAc increased the motivation to respond for sucrose, whereas infusion of NPY in either NAc or LH increased sucrose consumption. In addition, the effect of intra‐VTA NPY on motivation for food was attenuated after pretreatment with the dopamine receptor antagonist alpha‐flupenthixol.ConclusionsSpecific limbic substrates through which NPY influences consumption of and motivation for palatable food were identified by these data. The motivational effects of NPY are exerted through the VTA, its consummatory effects through the LH, and the NAc is involved in both.
Crystallographic structure of ChitA, a glycoside hydrolase family 19, plant class IV chitinase from Zea mays
Authors: Chaudet Marcia M. , Naumann Todd A. , Price Neil P.J. , Rose David R. 
Published: February 2014

ABSTRACTMaize ChitA chitinase is composed of a small, hevein‐like domain attached to a carboxy‐terminal chitinase domain. During fungal ear rot, the hevein‐like domain is cleaved by secreted fungal proteases to produce truncated forms of ChitA. Here, we report a structural and biochemical characterization of truncated ChitA (ChitA ΔN), which lacks the hevein‐like domain. ChitA ΔN and a mutant form (ChitA ΔN‐EQ) were expressed and purified; enzyme assays showed that ChitA ΔN activity was comparable to the full‐length enzyme. Mutation of Glu62 to Gln (ChitA ΔN‐EQ) abolished chitinase activity without disrupting substrate binding, demonstrating that Glu62 is directly involved in catalysis. A crystal structure of ChitA ΔN‐EQ provided strong support for key roles for Glu62, Arg177, and Glu165 in hydrolysis, and for Ser103 and Tyr106 in substrate binding. These findings demonstrate that the hevein‐like domain is not needed for enzyme activity. Moreover, comparison of the crystal structure of this plant class IV chitinase with structures from larger class I and II enzymes suggest that class IV chitinases have evolved to accommodate shorter substrates.
Structural characterization of MepB from Staphylococcus aureus reveals homology to endonucleases
Authors: Agah Sayeh , Poulos Sandra , Banchs Christian , Faham Salem 
Published: February 2014

AbstractThe MepRAB operon in Staphylococcus aureus has been identified to play a role in drug resistance. Although the functions of MepA and MepR are known, little information is available on the function of MepB. Here we report the X‐ray structure of MepB to 2.1 Å revealing its structural similarity to the PD‐(D/E)XK family of endonucleases. We further show that MepB binds DNA and RNA, with a higher affinity towards RNA and single stranded DNA than towards double stranded DNA. Notably, the PD‐(D/E)XK catalytic active site residues are not conserved in MepB. MepB's association with a drug resistance operon suggests that it plays a role in responding to antimicrobials. This role is likely carried out through MepB's interactions with nucleic acids.
Expanding the eco‐evolutionary context of herbicide resistance research
Authors: Neve Paul , Busi Roberto , Renton Michael , Vila‐Aiub Martin M 
Published: February 2014

AbstractThe potential for human-driven evolution in economically and environmentally important organisms in medicine, agriculture and conservation management is now widely recognised. The evolution of herbicide resistance in weeds is a classic example of rapid adaptation in the face of human-mediated selection. Management strategies that aim to slow or prevent the evolution of herbicide resistance must be informed by an understanding of the ecological and evolutionary factors that drive selection in weed populations. Here, we argue for a greater focus on the ultimate causes of selection for resistance in herbicide resistance studies. The emerging fields of eco-evolutionary dynamics and applied evolutionary biology offer a means to achieve this goal and to consider herbicide resistance in a broader and sometimes novel context. Four relevant research questions are presented, which examine (i) the impact of herbicide dose on selection for resistance, (ii) plant fitness in herbicide resistance studies, (iii) the efficacy of herbicide rotations and mixtures and (iv) the impacts of gene flow on resistance evolution and spread. In all cases, fundamental ecology and evolution have the potential to offer new insights into herbicide resistance evolution and management. © 2014 Society of Chemical Industry
Yorckbrücken Berlin
Authors: Lorenz Werner 
Published: February 2014

AbstractNach Jahrzehnte langem Verfall ist für die Berliner Yorckbrücken, ein denkmalgeschütztes Ensemble von 26 zwischen 1875 und 1934 errichteten Bahnbrücken, ein konstruktiv und statisch unterlegtes Revitalisierungskonzept erarbeitet worden. Es sieht vor, einen Teil der Brücken neuen Nutzungen als Geh‐, Radweg‐ oder Grünbrücken zuzuführen, andere werden weiterhin von der Bahn genutzt und ersetzt. Als besondere Herausforderung für die Entwicklung der zu erhaltenden Brücken erwiesen sich die gusseisernen Stützen. Unmittelbar neben einer stark befahrenen Straße angeordnet, sind sie für Anpralllasten nicht nachweisbar. Nach einer Einführung zu Geschichte und Bedeutung der Brücken und den denkmalpflegerischen Leitlinien diskutiert der Beitrag verschiedene Varianten zur Lösung der Gussstützenproblematik. Die Umsetzung der Vorzugsvariante wird am Beispiel der Brücke Nr. 5 vorgestellt, die heute die älteste noch erhaltene Stahlbrücke Berlins ist. Als erste der Yorckbrücken wurde sie 2011/2012 im Sinne eines Prototyps instand gesetzt.Yorckbrücken Berlin – Revitalisation of a listed ensemble of railway bridges including cast iron columns at risk of vehicle impacts. Berlin’s Yorckbrücken are a listed ensemble of 26 railway bridges built between 1875 and 1934. After decades of neglect, a revitalisation concept has been developed, which takes into account their particular structural conditions. It proposes a new usage for several of the original bridges as pedestrian, bicycle or wildlife overpasses, while others that continue as railway bridges will be replaced. Existing cast iron columns, located closely besides a busy road, proved to be a serious challenge for the planned new uses, as they are not verifiable for impact loads. After an introduction into the history and significance of the bridges as well as the preservation guidelines, the article discusses alternative solutions for the problem of the cast iron columns. The implementation of the preferred alternative is presented through the example of bridge no. 5, which is the oldest surviving steel bridge in Berlin. It has been reconditioned in 2011/2012 to act as a sort of prototype for future works on other Yorckbrücken.
Lithium Copper(I) Orthophosphates Li3–xCuxPO4: Synthesis, Crystal Structures, and Electrochemical Properties
Authors: Snyder Katharina , Raguž Branimir , Hoffbauer Wilfried , Glaum Robert , Ehrenberg Hartmut , Herklotz Markus 
Published: February 2014

AbstractAlong the quasi‐binary section Li3PO4 ‐ CuI3PO4 three different phases Li3–xCuIxPO4 each with extended homogeneity range occur under equilibrium conditions (650 ≤ ; ≤ 700 °C). According to single‐crystal X‐ray structure analyses Phase 1 (0 < x ≤ 0.7) adopts the HT‐ or β‐Li3PO4 structure type [Li2.6CuI0.4PO4, Pnma (no. 62), Z = 4, a = 10.4612(2) Å, b = 6.1690(3) Å, c = 4.9854(2) Å, R1 = 0.023, wR2 = 0.062, Goof = 1.12] and Phase 2 (0.9 ≤ x ≤ 1.8) is isotypic to LT‐ or α‐Li3PO4 [Li2.05CuI0.95PO4, Pnm21 (no. 31), Z = 2, a = 6.2113(8) Å, b = 5.2597(7) Å, c = 4.9904(5) Å, R1 = 0.040, wR2 = 0.108, Goof = 0.98]. A preliminary structure model for the copper‐rich Phase 3 (2.1 ≤ x ≤ 2.8) [“Li0.6CuI2.4PO4”, P$\bar{3}$ (no. 147), a = 6.223(1) Å, c = 5.3629(5) Å] could be refined to R1 = 0.07. Sharp 31P‐MAS‐NMR resonances observed in the spectra of Li2.6CuI0.4PO4 (δiso = 10.4 ppm), Li2.05CuI0.95PO4 (δiso = 12.4 ppm), and Li0.84CuI2.16PO4 (δiso = 10.9 ppm) provide evidence for the absence of paramagnetic Cu2+ ions. Pure copper(I) orthophosphate CuI3(PO4) exists as a homogeneous melt ( ≥ 800 °C) and can be obtained as thermodynamically metastable solid by quenching. It is isotypic to Phase 3 [a = 6.284(3) Å, c = 5.408(5) Å]. Electrochemical delithiation of Li2.05CuI0.95PO4 (C/10, C/30) indicates two partially reversible oxidation processes between 3.75 V and 4.80 V (vs. Li0/Li+).
Microwave‐assisted Synthesis, Structure, and Properties of a Heptanuclear Cobalt Cluster with 2‐Ethyliminomethyl‐6‐methoxy‐phenol
Authors: Huang Qiu‐Ping , Li Gui , Zhang Hai‐Yang , Zhang Shu‐Hua , Li He‐Ping 
Published: February 2014

AbstractThe heptanuclear cobalt cluster [Co7(emmp)6(CH3O)6]·(ClO4)2 (1) (Hemmp = 2‐ethyliminomethyl‐6‐methoxy‐phenol) was synthesized by the microwave‐assisted reaction of Co(ClO4)2·6H2O with 3‐ethoxy‐2‐hydroxy‐benzaldehyde (Hehb) and ethylamine in mixed solvent (acetonitrile:methanol = 1:1). Complex 1 was characterized by IR spectroscopy, elemental analysis, and X‐ray single‐crystal diffraction. The magnetic properties of 1 are discussed. Complex 1 displays dominant ferromagnetic interactions from the nature of the binding modes through μ3‐OCH3 and μ2‐phenoxo.
Extraction of Parabens from Water Samples Using Cloud Point Extraction with a Non‐Ionic Surfactant with β‐Cyclodextrin as Modifier
Authors: Noorashikin Md Saleh , Raoov Muggundha , Mohamad Sharifah , Abas Mhd Radzi 
Published: February 2014

AbstractA cloud point extraction process using a silicone non‐ionic surfactant to extract selected parabens compounds from water samples was investigated using reversed phase high performance liquid chromatography. The cloud point extraction process, in the presence of β‐cyclodextrin (β‐CD) as a modifier, is a new extraction process which was optimized with five parameters, i.e. salt concentration, pH of the solution, temperature, surfactant concentration and β‐CD concentration. The developed method with the β‐CD modifier results in an excellent performance on detection of parabens from water samples with limits of detection in the range of 0.017–0.043 μg/L and percentage recoveries from 90.5 to 98.9 %.
Pyropheophytin a and 1,2‐Diacyl‐glycerols Over Time Under Different Storage Conditions in Natural Olive Oils
Authors: Guillaume C. , Gertz Ch. , Ravetti L. 
Published: February 2014

AbstractThe effect of storage conditions (light, temperature, container types) and time on the quality of natural olive oils from different cultivars and Australian regions were studied. The oils’ changing quality was monitored through several physico‐chemical methods (free fatty acids, peroxide value, UV‐spectrometry (K232, K270 and ΔK), induction time, total polyphenol content, bitterness, pyropheophytin a and 1,2‐diacyl‐glycerol content) and sensory analysis over 24 months. Pyropheophytins a and 1,2‐diacyl‐glycerols criteria showed very good performance as indicators of overall olive oil quality and freshness as well as highlighting any problems during the storage of the product. Pyropheophytin a increment averaged 7 % per year and the 1,2‐diacyl‐glycerols decreased at an average of 23 % per year at normal storage conditions over time.
The high-supply, current-dominated continental margin of southeastern South America during the late Quaternary
Authors: Lantzsch Hendrik , Hanebuth Till J.J. , Chiessi Cristiano M. , Schwenk Tilmann , Violante Roberto A. 
Published: February 2014

AbstractThe continental margin off the La Plata Estuary (SE South America) is characterized by high fluvial sediment supply and strong ocean currents. High-resolution sediment-acoustic data combined with sedimentary facies analysis, AMS-14C ages, and neodymium isotopic data allowed us to reconstruct late Quaternary sedimentary dynamics in relation to the two major sediment sources, the La Plata Estuary and the Argentine margin. Sediments from these two provinces show completely different dispersal patterns. We show that the northward-trending La Plata paleo-valley was the sole transit path for the huge volumes of fluvial material during lower sea levels. In contrast, material from the Argentine margin sector was transported northwards by the strong current system. Despite the large sediment volumes supplied by both sources, wide parts of the shelf were characterized by either persistent non-deposition or local short-term depocenter formation. The location and formation history of these depocenters were primarily controlled by the interplay of sea level with current strength and local morphology. The high sediment supply was of secondary importance to the stratigraphic construction, though locally resulting in high sedimentation rates. Thus, the shelf system off the La Plata Estuary can be considered as a hydrodynamic-controlled end-member.
Diagnosing mixing in stratified turbulent flows with a locally defined available potential energy
Authors: Scotti Alberto , White Brian 
Published: February 2014

AbstractA local available potential energy (APE) density useful as suitable diagnostic tool in turbulent stratified flows is considered under the Boussinesq approximation. The local APE is positive, and in the limit of infinitesimal perturbation from an equilibrium state recovers the Lorenz energy cycle definition of APE. In a turbulent stratified flow, the APE can be Reynolds-decomposed into non-trivial mean and turbulent components, which are connected to the mean and turbulent kinetic energy by suitably defined fluxes. We show that the turbulent buoyancy flux $\overline{w'b'}$ and the rate of production of turbulent APE coincide only under very special circumstances. The framework is applied to derive some global bounds on the mixing efficiency of some representative flows.
Approach to transverse uniformity of concentration distribution of a solute in a solvent flowing along a straight pipe
Authors: Wu Zi , Chen G. Q. 
Published: February 2014

AbstractAssociated with Taylor’s classical analysis of scalar solute dispersion in the laminar flow of a solvent in a straight pipe, this work explores the approach towards transverse uniformity of concentration distribution. Mei’s homogenization technique is extended to find solutions for the concentration transport. Chatwin’s result for the approach to longitudinal normality is recovered in terms of the mean concentration over the cross-section. The asymmetrical structure of the concentration cloud and the transverse variation of the concentration distribution are concretely illustrated for the initial stage. The rate of approach to uniformity is shown to be much slower than that to normality. When the longitudinal normality of mean concentration is well established, the maximum transverse concentration difference remains near one-half of the centroid concentration of the cloud. A time scale up to$10 R^2/D$($R$is the radius of the pipe and$D$is the molecular diffusivity) is suggested to characterize the transition to transverse uniformity, in contrast to the time scale of$0.1 R^2/D$estimated by Taylor for the initial stage of dispersion, and that of$1.0 R^2/D$by Chatwin for longitudinal normality.
Flow-induced vibrations of a rotating cylinder
Authors: Bourguet Rémi , Lo Jacono David 
Published: February 2014

AbstractThe flow-induced vibrations of a circular cylinder, free to oscillate in the cross-flow direction and subjected to a forced rotation about its axis, are analysed by means of two- and three-dimensional numerical simulations. The impact of the symmetry breaking caused by the forced rotation on the vortex-induced vibration (VIV) mechanisms is investigated for a Reynolds number equal to $100$, based on the cylinder diameter and inflow velocity. The cylinder is found to oscillate freely up to a rotation rate (ratio between the cylinder surface and inflow velocities) close to $4$. Under forced rotation, the vibration amplitude exhibits a bell-shaped evolution as a function of the reduced velocity (inverse of the oscillator natural frequency) and reaches $1.9$ diameters, i.e. three times the maximum amplitude in the non-rotating case. The free vibrations of the rotating cylinder occur under a condition of wake–body synchronization similar to the lock-in condition driving non-rotating cylinder VIV. The largest vibration amplitudes are associated with a novel asymmetric wake pattern composed of a triplet of vortices and a single vortex shed per cycle, the ${\rm T} + {\rm S}$ pattern. In the low-frequency vibration regime, the flow exhibits another new topology, the U pattern, characterized by a transverse undulation of the spanwise vorticity layers without vortex detachment; consequently, free oscillations of the rotating cylinder may also develop in the absence of vortex shedding. The symmetry breaking due to the rotation is shown to directly impact the selection of the higher harmonics appearing in the fluid force spectra. The rotation also influences the mechanism of phasing between the force and the structural response.