bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evolution of the Metazoan Extracellular Matrix
Authors: Adams Josephine C 
Published: April 2013

AbstractThe metazoan extracellular matrix (ECM), an extracellular system of insoluble networks, sheets and fibrils of proteinaceous material, is a central mediator of multicellularity that is required for developmental processes, tissue organisation, homoeostasis and control of cell phenotypes throughout life. Comparative genomics enables the repertoire of ECM components encoded by species from different phyla to be examined systematically. These studies have identified a core ECM adhesome that arose apparently on the metazoan stem lineage through gene and domain innovations and domain shuffling. In vertebrates, additional complexity of ECM structure and function has arisen through expansion of gene families, splice variants and the inception of novel ECM components including fibril‐associated collagen with interrupted triple helices collagens, fibronectin, hyaluronan, tenascins and secreted proteoglycans of bone and cartilage. Protostome phyla also include many lineage‐specific ECM innovations and diversifications that function in prey‐capture mechanisms, the assembly of protective exterior structures, and internal organs.Key Concepts:The extracellular matrix (ECM) is an insoluble network of collagens, glycoproteins, proteoglycans and glycosaminoglycans.Different morphological forms of ECM are apparent in early diverging and bilaterian animals.Comparative genomics has identified a conserved core ECM adhesome, that includes integrin adhesion receptors, matrix proteases and the central ECM components of connective ECM and basement membranes.The ECM components of this core adhesome are specific to the metazoa.It is likely that the ECM components of the core adhesome were important for evolution of multi‐cellularity in the metazoa.Additional ECM diversity has arisen in vertebrates through large‐scale genome duplication events, domain innovations, and novel ECM components.Lineage‐specific ECM diversity is also apparent in invertebrates; in cuticles, shells and specialised structures as well as internal organs.Overall, the metazoan ECM shows extensive adaptive radiation as well as great conservation of the core ECM components.
GIS analysis reveals the high diversity and conservation value of mollusc assemblages in the floodplain wetlands of the lower Bug River (East Poland)
Authors: Jurkiewicz‐Karnkowska Ewa , Karnkowski Paweł 
Published: April 2013

ABSTRACT

The distribution and species richness of aquatic molluscs were analysed within a 186‐km‐long section of a large (755‐km‐long) lowland river floodplain using GIS maps. Special attention was paid to threatened species.
An attempt was made to identify local ‘hotspots’ of molluscan diversity and to determine the most important areas for conservation based on species richness, number of threatened species and indices of synthetic conservation (Q) and centres of population density (ICD).
Over four years of investigation, carried out in 176 water bodies, a rich malacofauna was identified: 58 species including 20 of elevated conservation concern.
GIS maps revealed numerous ‘hotspots’ of mollusc species richness and higher incidence of threatened species, as well as areas characterized by raised Q and ICD indices.
Water body size and hydrological connectivity positively influenced species richness and Q values. The highest values of these variables were found in large water bodies having limited surficial connectivity with the river channel.
Species richness, numbers of threatened species, and Q and ICD values were significantly higher in younger permanent water bodies compared with semi‐permanent or temporary ones representing advanced successional stages.
Spatial visualization data collected in the study area indicate that the most valuable sites for the conservation of aquatic molluscs include both sides of the river in the lower part of the middle stretch of the lower Bug River valley. Copyright © 2013 John Wiley & Sons, Ltd.
A plant‐based index of biological integrity in permanent marsh wetlands yields consistent scores in dry and wet years
Authors: Wilson Matthew J. , Bayley Suzanne E. , Rooney Rebecca C. 
Published: April 2013

ABSTRACT

Plant‐based assessments can contribute to wetland conservation and management by providing a standardized method to monitor biological communities in relation to human activity. One major challenge, however, is that their measurements must be fairly insensitive to temporal variation in community composition, which can be difficult since marsh plant communities are known to be influenced by natural climatic cycles.
Variation in the scores for an index of biological integrity (IBI) was evaluated in relation to plant community changes that occurred between years with differing precipitation inputs throughout the growing season (dry: 240 mm in 2008, 198 mm in 2009; wet: 324 mm in 2010, 329 mm in 2011). Species composition and IBI scores were measured by sampling macrophytes in the centre of the wet meadow zone at 47 semi‐permanent to permanent natural and constructed marshes.
Non‐metric multidimensional scaling (NMS) ordinations revealed that although plant community composition shifted between dry and wet years, IBI scores were sensitive to only 21% of the total inter‐annual variation in species composition. The first NMS axis was positively correlated with IBI scores (r = 0.85) as well as several environmental parameters (r2 > 0.2), including dissolved organic carbon, total nitrogen, potassium, shoreline slope, and salinity.
The wet meadow IBI also yielded consistent scores between dry and wet years (Spearman's rho = 0.82; Wilcoxon z‐score = 0.53, P‐value = 0.60) and was able to distinguish a change in biological condition among sites against a backdrop of natural variation (F‐test = 3.0, P < 0.001).
These findings provide support for the continued use of plants as indicators of wetland condition in permanent northern prairie marshes, providing that the range in water levels is moderate. Copyright © 2013 John Wiley & Sons, Ltd.
The many faces of article‐level metrics
Authors: Lin Jennifer , Fenner Martin 
Published: April 2013

AbstractEditor's SummaryThe Public Library of Science (PLOS) collects a range of alternative metrics about the articles they publish to provide different, more meaningful and granular insights into reader response. PLOS captures usage statistics, social shares, academic bookmarks and both scholarly and non‐scholarly citations, all offering distinct types of information. Early interest in an article is more apparent through HTML views and mentions on social sharing sites than usage statistics, and Mendeley bookmarking reflects interest but does not correlate with citation count. An article's appearance in citation databases commonly takes at least two years. Mentions in blogs often stimulate commentary and critique. Instead of presenting only a simplistic citation number, PLOS offers article level metrics (ALM) signposts reflecting ALM that capture the variety of response, audience, timing, purpose and impact of a scientific article.
On‐Chip Catalytic Microreactors for Modern Catalysis Research
Authors: Xu Bin‐Bin , Zhang Yong‐Lai , Wei Shu , Ding Hong , Sun Hong‐Bo 
Published: April 2013

AbstractOver the past two decades, microfluidics, represented by lab‐on‐a‐chip (LoC) systems, have been developed because of their unique advantages of low reactant consumption, environmental friendliness, high safety, high efficiency, high sensitivity, portability, and easy handling of reactants. The distinguishing features of microfluidics have made the on‐chip reactor a highly efficient platform for general chemical experiments, especially catalysis. In this paper, through a brief review of the recent work on microfluidic catalysis, we highlight the importance of on‐chip catalytic microreactors. New approaches to the fabrication of on‐chip catalytic microreactors and their integration with multifunctional components are briefly introduced. Finally, the current challenges and future perspectives of this up‐and‐coming field are discussed based on our own opinions. It is believed that, with the progress of interdisciplinary cooperation, microfluidics and catalysis could be complementary sciences; catalysts may play a very important role in LoC systems, and on‐chip catalytic microreactors could be a highly efficient experimental platform for modern catalysis research.
Synthesis of [m.n]Cyclophanes: Regiochemistry Transfer from Vinyl Halides to Cyclophanes via Fischer Carbene Complexes
Authors: Wang Huan , Predeus Alexander V. , Wulff William D. 
Published: April 2013

AbstractThe double benzannulation of bis‐carbene complexes of chromium with α,ω‐diynes generates [m.n]cyclophanes in which all three rings are generated in a single reaction. This triple annulation process is very flexible allowing for the construction of symmetrical [n.n]cyclophanes and unsymmetrical [m.n]cyclophanes as well as isomers in which the two benzene rings are both meta bridged or both para bridged, and isomers that contain both meta and para bridges. The connectivity patterns of the bridges in the cyclophanes can be controlled by regioselectivity transfer from the bis‐vinyl carbene complexes in which the substitution pattern of the vinyl groups in the carbene complexes dictate the connectivity pattern in the [m.n]cyclophanes. This synthesis of [n.n]cyclophanes is quite flexible with regard to ring size and can be used with tether lengths ranging from n=2 to n=16 and thus to ring sizes with up to 40 member rings. The only limitation to regioselectivity transfer from the carbene complexes to the [m.n]cyclophanes was found in the synthesis of para,para‐cyclophanes with four carbon tethers for which the loss of fidelity occurred with the unexpected formation of meta,para‐cyclophanes.
Chromaticity‐matched but spectrally different light source effects on simple and complex color judgments
Authors: Veitch Jennifer A. , Whitehead Lorne A. , Mossman Michele , Pilditch Toby D. 
Published: April 2013

AbstractAs light‐emitting diode (LED) light sources mature, lighting designers will be able to deliver white light with a variety of spectral power distributions and a variety of color rendering properties. This experiment examined the effects of three spectral power distributions (SPDs) that were matched in illuminance and chromaticity on three measures of color perception: one objective (performance on the Farnsworth‐Munsell 100 hue test) and two subjective (judgments of the attractiveness of one's own skin, and preferences for the saturation of printed images). The three SPDs were a quartz‐halogen (QH) lamp and two LED sources that were matched to the QH lamp in terms of both illuminance and chromaticity; the three light sources were nominally CCT = 3500 K, x = 0.40, y = 0.39 and ∼ 400 lx. LED A used three channels (red, green, blue), and had very poor color rendering (Ra = 18). LED B used four channels (red, amber, cyan, white) and had very good color rendering (Ra = 96, whereas the QH had Ra = 98). Secondary hypotheses addressed the effects of age and skin and eye color on the dependent measures. As expected, LED A delivered very different color perceptions on all measures when compared to QH; LED B did not differ from QH. The results show that it is possible for LED sources to match the familiar incandescent sources. However, although it is possible to deliver what appear to be millions of colors with a three‐chip (RGB) device, there is the risk of creating a very poor luminous environment. © 2013 National Research Council Canada and Wiley Periodicals, Inc. Col Res Appl, 39, 263–274, 2014; Published Online 12 April 2013 in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/col.21811
Wired Enzyme Electrodes—A Retroperspective Story about an Exciting Time at University of Texas at Austin and Its Impact on My Scientific Career
Authors: Lindquist Sten‐Eric 
Published: April 2013

AbstractThe present paper features an exciting time in the late 1980s when I, as a visiting scientist, had the privilege to participate in the early and very exciting development of the in vivo redox‐polymer‐wired glucose sensor in Professor Adam Heller’s laboratory at the Department of Chemical Engineering at University of Texas at Austin. This story is followed by an overview of the research my visit initiated at Uppsala University. In collaboration with Swedish colleagues, we explored a few of the many possibilities to form new biosensors by utilizing Prof. Heller’s concept of cross‐linked redox‐polymer/redox‐enzyme electrodes.
Pulmonary Gas Exchange and Acid‐Base Balance During Exercise
Authors: Stickland Michael K. , Lindinger Michael I. , Olfert I. Mark , Heigenhauser George J. F. , Hopkins Susan R. 
Published: April 2013

AbstractAs the first step in the oxygen‐transport chain, the lung has a critical task: optimizing the exchange of respiratory gases to maintain delivery of oxygen and the elimination of carbon dioxide. In healthy subjects, gas exchange, as evaluated by the alveolar‐to‐arterialPO2difference (A‐aDO2), worsens with incremental exercise, and typically reaches anA‐aDO2of approximately 25 mmHg at peak exercise. While there is great individual variability,A‐aDO2is generally largest at peak exercise in subjects with the highest peak oxygen consumption. Inert gas data has shown that the increase inA‐aDO2is explained by decreased ventilation‐perfusion matching, and the development of a diffusion limitation for oxygen. Gas exchange data does not indicate the presence of right‐to‐left intrapulmonary shunt developing with exercise, despite recent data suggesting that large‐diameter arteriovenous shunt vessels may be recruited with exercise. At the same time, multisystem mechanisms regulate systemic acid‐base balance in integrative processes that involve gas exchange between tissues and the environment and simultaneous net changes in the concentrations of strong and weak ions within, and transfer between, extracellular and intracellular fluids. The physicochemical approach to acid‐base balance is used to understand the contributions from independent acid‐base variables to measured acid‐base disturbances within contracting skeletal muscle, erythrocytes and noncontracting tissues. In muscle, the magnitude of the disturbance is proportional to the concentrations of dissociated weak acids, the rate at which acid equivalents (strong acid) accumulate and the rate at which strong base cations are added to or removed from muscle. © 2013 American Physiological Society.Compr Physiol3:693‐739, 2013.
Circadian Rhythms in Liver Physiology and Liver Diseases
Authors: Tong Xin , Yin Lei 
Published: April 2013

AbstractIn mammals, circadian rhythms function to coordinate a diverse panel of physiological processes with environmental conditions such as food and light. As the driving force for circadian rhythmicity, the molecular clock is a self‐sustained transcription‐translational feedback loop system consisting of transcription factors, epigenetic modulators, kinases/phosphatases, and ubiquitin E3 ligases. The molecular clock exists not only in the suprachiasmatic nuclei of the hypothalamus but also in the peripheral tissues to regulate cellular and physiological function in a tissue‐specific manner. The circadian clock system in the liver plays important roles in regulating metabolism and energy homeostasis. Clock gene mutant animals display impaired glucose and lipid metabolism and are susceptible to diet‐induced obesity and metabolic dysfunction, providing strong evidence for the connection between the circadian clock and metabolic homeostasis. Circadian‐controlled hepatic metabolism is partially achieved by controlling the expression and/or activity of key metabolic enzymes, transcription factors, signaling molecules, and transporters. Reciprocally, intracellular metabolites modulate the molecular clock activity in response to the energy status. Although still at the early stage, circadian clock dysfunction has been implicated in common chronic liver diseases. Circadian dysregulation of lipid metabolism, detoxification, reactive oxygen species (ROS) production, and cell‐cycle control might contribute to the onset and progression of liver steatosis, fibrosis, and even carcinogenesis. In summary, these findings call for a comprehensive study of the function and mechanisms of hepatic circadian clock to gain better understanding of liver physiology and diseases. © 2013 American Physiological Society.Compr Physiol3:917‐940, 2013.
Routing bandwidth guaranteed paths for traffic engineering in WiMAX mesh networks
Authors: Misra Sudip , Ghosh Tushar I. , Obaidat Mohammad S. 
Published: April 2013

SUMMARYIn this paper, the authors present a novel algorithm for computing bandwidth guaranteed paths for traffic engineering in WiMAX IEEE 802.16 standard based networks using the mesh topology. The underlying algorithm fulfills routing requests ‘on the fly’ without a priori knowledge of future requests. This problem is motivated by the need for efficient handling of traffic and network resource utilization. The key idea behind the solution is the use of heuristic methods to defer routing through certain nodes, which have a higher chance of getting selected because of hop constraints, so that they can be prevented from congestion. Simulation‐based performance evaluation shows that the proposed algorithm performs well in comparison with the selected benchmarks on metrics such as the number of rejected requests and the active links present in the network. Copyright © 2013 John Wiley & Sons, Ltd.
Wheat genotypes differing in aluminum tolerance differ in their growth response to CO2 enrichment in acid soils
Authors: Tian Qiuying , Zhang Xinxin , Gao Yan , Bai Wenming , Ge Feng , Ma Yibing , Zhang Wen‐Hao 
Published: April 2013

AbstractAluminum (Al) toxicity is a major factor limiting plant growth in acid soils. Elevated atmospheric CO2 [CO2] enhances plant growth. However, there is no report on the effect of elevated [CO2] on growth of plant genotypes differing in Al tolerance grown in acid soils. We investigated the effect of short‐term elevated [CO2] on growth of Al‐tolerant (ET8) and Al‐sensitive (ES8) wheat plants and malate exudation from root apices by growing them in acid soils under ambient [CO2] and elevated [CO2] using open‐top chambers. Exposure of ET8 plants to elevated [CO2] enhanced root biomass only. In contrast, shoot biomass of ES8 was enhanced by elevated [CO2]. Given that exudation of malate to detoxify apoplastic Al is a mechanism for Al tolerance in wheat plants, ET8 plants exuded greater amounts of malate from root apices than ES8 plants under both ambient and elevated [CO2]. These results indicate that elevated [CO2] has no effect on malate exudation in both ET8 and ES8 plants. These novel findings have important implications for our understanding how plants respond to elevated [CO2] grown in unfavorable edaphic conditions in general and in acid soils in particular.
Spatial scales of genetic structure and gene flow in Calochortus albus (Liliaceae)
Authors: Henss Jillian M. , Moeller Jackson R. , Theim Terra J. , Givnish Thomas J. 
Published: April 2013

AbstractCalochortus (Liliaceae) displays high species richness, restriction of many individual taxa to narrow ranges, geographic coherence of individual clades, and parallel adaptive radiations in different regions. Here we test the first part of a hypothesis that all of these patterns may reflect gene flow at small geographic scales. We use amplified fragment length polymorphism variation to quantify the geographic scales of spatial genetic structure and apparent gene flow in Calochortus albus, a widespread member of the genus, at Henry Coe State Park in the Coast Ranges south of San Francisco Bay. Analyses of 254 mapped individuals spaced 0.001–14.4 km apart show a highly significant decline in genetic identity with ln distance, implying a root‐mean‐square distance of gene flow σ of 5–43 m. STRUCTURE analysis implies the existence of 2–4 clusters over the study area, with frequent reversals among clusters over short distances (<200 m) and a relatively high frequency of admixture within individuals at most sampling sites. While the intensity of spatial genetic structure in C. albus is weak, as measured by the Sp statistic, that appears to reflect low genetic identity of adjacent plants, which might reflect repeated colonizations at small spatial scales or density‐dependent mortality of individual genotypes by natural enemies. Small spatial scales of gene flow and spatial genetic structure should permit, under a variety of conditions, genetic differentiation within species at such scales, setting the stage ultimately for speciation and adaptive radiation as such scales as well.
Homogeneous metal complex catalyzed conjugation of methyl linoleate
Authors: Behr Arno , Witte Henning , Bayrak Zeynep 
Published: April 2013

Conjugated methyl linoleates (CML) can be produced by homogeneous transition metal catalysis under mild reaction conditions, low catalyst concentrations and short reaction times in nearly quantitative yield from methyl linoleate (ML), an easily accessible intermediate product of the oleochemical industry. The best catalyst proved to be the Wilkinson‐catalyst RhCl(PPh3)3 (1 mol%) activated by the co‐catalyst tin(II)chloride‐dihydrate (2.5 mol%) in the solvent methanol. A yield of 93% of conjugated methyl linoleates can be obtained under mild reaction conditions at 60°C and low reaction times of 3 h.See commentary by Philippaerts et al. [p. 717–720], http://dx.doi.org/10.1002/ejlt.201300101
Halogenated Benzene Cation Radicals
Authors: Molski Matthias J. , Khanfar Monther A. , Shorafa Hashem , Seppelt Konrad 
Published: April 2013

AbstractThe benzene cation radicals [C6F5‐CF3]+, [1,4‐C6F4(CF3)2]+, [1,2,4,5‐C6H2Cl4]+, [C6F5‐C6F5]+, and [C6Br6]+ have been obtained as salts with fluoroarsenic and fluoroantimony counterions. Their structures have been obtained by single‐crystal structure determinations, and supported by ESR measurements and DFT calculations. [C6F5‐CF3]+, [1,4‐C6F4(CF3)2]+, and [1,2,4,5‐C6H2Cl4]+ have the predicted bisallyl type structure. [C6F5‐C6F5]+ can be described as having a quinoid form with a strengthened central C–C bond and a smaller dihedral angle as compared to the neutral C6F5‐C6F5. [C6Br6]+ is the missing link between [C6F6]+, [C6Cl6]+, and [C6I6]+. It has a Jahn–Teller distortion, though weaker than [C6F6]+ and [C6Cl6]+, in contrast to [C6I6]+, which remains in a regular hexagon structure.
Anion‐π Interaction: An Influential Force in Solid State Molecular Microstructures
Authors: Giese Michael , Albrecht Markus , Valkonen Arto , Rissanen Kari 
Published: April 2013

AbstractThe crystal structures of simple triphenyl(pentafluorobenzyl)phosphonium salts provide crucial data on the influence of anion size on the molecular structure of bis(pentafluorobenzyl)phosphonium cations containing two adjacent electron‐deficient moieties. Whereas the bromide anions interact by anion‐π interaction in a 1:1 mode with the pentafluorobenzene unit Z‐configured, the bulkier anions iodide, tetrafluoroborate, and hexafluorophosphate result in a 1:2 tweezer‐like anti‐configuration in which one anion interacts simultaneously with two pentafluorobenzene units. When spatial separation of the two electron‐deficient rings match the size of the anion, anion‐π interactions induce a conformational change from the anti‐form observed for the smaller anion to the tweezer‐like syn‐form.
Tuning the Halide Affinity of Quinoline‐Based Anion Receptors
Authors: Sun Zhan‐Hu , Albrecht Markus , Fröhlich Roland 
Published: April 2013

AbstractThe binding behaviour of (thio)urea‐ and amide‐functionalized quinoline‐based anion receptors towards halide anions was investigated in detail in CDCl3 and [D6]DMSO solutions by using 1H and 19F NMR spectroscopic methods. The electronic, solvent, and fluoro‐substitution effects were studied. The (thio)urea‐ and amide‐functionalized quinoline‐based anion receptors showed medium to strong anion affinity and good selectivity in solution. Single crystals of key compounds were obtained and studied by X‐ray diffraction spectroscopy.