bluuebunny/crossref_metadata_2025 huggingface dataset:
Supporting Public Access to Research Results
Authors: Lapinski P. Scott , Osterbur David , Parker Joshua , McCray Alexa T.
Published: June 2014

We posed the question of what services an academic library can best provide to support the NIH Public Access Policy. We approached the answer to this question through education, collaboration, and tool-building. As a result, over the last four years we have engaged over 1,500 participants in discussions of public access to research results, forged alliances with dozens of partners, and built online tools to ease the process of complying with the NIH policy. We conclude that librarians working in collaboration with other key constituencies can have a positive impact on improving access to the results of scientific research.
Multifaulting in a tectonic syntaxis revealed by InSAR: The case of the Ziarat earthquake sequence (Pakistan)
Authors: Pinel‐Puysségur B. , Grandin R. , Bollinger L. , Baudry C.
Published: June 2014

On 28–29 October 2008, within 12 h, two similar Mw = 6.4 strike‐slip earthquakes struck Baluchistan (Pakistan), as part of a complex seismic sequence. Interferometric Synthetic Aperture Radar (InSAR) data reveal that the peak of surface displacement is near the Ziarat anticline, a large active fold affected by Quaternary strike‐slip faulting. All coseismic interferograms integrate the deformation due to both earthquakes. As their causative faults ruptured close to each other, the individual signals cannot be separated. According to their focal mechanisms, each earthquake may have activated a NE‐SW sinistral or a NW‐SE dextral fault segment, which leads to four possible scenarios of fault orientations. A nonlinear inversion of the InSAR data set allows rejecting two scenarios. The best slip distributions on the two fault segments for the two remaining scenarios are determined by linear inversion. Stress‐change modeling favors a scenario involving two abutting conjugate strike‐slip faults. Two other fault segments accommodated left‐lateral strike slip during the seismic sequence. The activated fault system includes multiple fault segments with different orientations and little surface expression. This may highlight, at a smaller scale, the distributed, possibly transient character of deformation within a broader right‐lateral shear zone. It suggests that the activated faults delineate a small tectonic block extruding and subtly rotating within the shear zone. It occurs in the vicinity of the local tectonic syntaxis where orogenic structures sharply turn around a vertical axis. These mechanisms could participate in the long‐term migration of active tectonic structures within this kinematically unstable tectonic syntaxis.
Sensitivity of seismic measurements to frequency‐dependent attenuation and upper mantle structure: An initial approach
Authors: Bellis C. , Holtzman B.
Published: June 2014

This study addresses the sensitivity of seismic attenuation measurements to dissipative mechanisms and structure in the Earth's upper mantle. The Andrade anelastic model fits experimental attenuation data with a mild power law frequency dependence and can be scaled from laboratory to Earth conditions. We incorporate this anelastic model into 400km 1‐D thermal profiles of the upper mantle. These continuous‐spectrum models are approximated by multiple relaxation mechanisms that are implemented within a finite‐difference scheme to perform wave propagation simulations in 1‐D domains. In two sets of numerical experiments, we evaluate the measurable signature of the intrinsic attenuation structure. The two sets are defined by thermal profiles with added step functions of temperature, varying in (i) amplitude and depth or (ii) amplitude and sharpness. The corresponding synthetic data are processed using both the conventional t* approach, i.e., a linear regression of the displacement frequency spectrum, and an alternative nonlinear fit to identify the integrated value of attenuation and its frequency dependence. The measured sensitivity patterns are analyzed to assess the effects of the anelastic model and its spatial distribution on seismic data (in the absence of scattering effects). We have two straightforward results: (1) the frequency dependence power law is recoverable from the measurements; (2) t* is sensitive to both the depth and the amplitude of the step, and it is insensitive to the sharpness of the step, in the 0.25 to 2 Hz band. There is much potential for gaining information about the upper mantle thermodynamic state from careful interpretation of attenuation.
Generation and detection of super small striations by F region HF heating
Authors: Najmi A. , Milikh G. , Secan J. , Chiang K. , Psiaki M. , Bernhardt P. , Briczinski S. , Siefring C. , Chang C.L. , Papadopoulos K.
Published: May 2014

Recent theoretical models and preliminary observations indicate that super small striations (SSS) in the plasma density with scale size of 10 cm can be excited by F region HF heating at frequencies close to multiples of the electron gyrofrequency. We present here new experimental results using the High Frequency Active Auroral Research Program ionospheric heater at a frequency close to the fourth electron gyroharmonic with simultaneous GPS, Stimulated Electromagnetic Emission, ionosonde, and occasional Incoherent Radar Scattering diagnostics. Differential phase measurements of GPS signals through the heated region indicated the presence of SSS with extremely high amplitude (δn/n = 0.2–0.3) at scale size comparable to the electron gyroradius. The highest amplitude of GPS scintillations coincide with the highest level of the Broad Upshifted Maximum (BUM) and occurred when the HF frequency is slightly above the fourth harmonic of the electron cyclotron frequency. Frequency sweeps indicate that the scintillation amplitude exhibits hysteresis similar to that observed for the BUM amplitude when the HF frequency is cycled about the fourth harmonic of the cyclotron frequency. The results favor a four wave parametric process as the physical mechanism of the SSS. Additional experiments allowed the determination of the excitation and decay rates of the SSS.
Steady contemporary deformation of the central Basin and Range Province, western United States
Authors: Hammond William C. , Blewitt Geoffrey , Kreemer Corné
Published: June 2014

We use data from western U.S. GPS networks to estimate the rate, pattern, and style of tectonic deformation of the central Basin and Range Province (BRP). Previous geodetic investigations have found the crust of eastern Nevada and western Utah to act as a rigid microplate, with zero deformation rates to within measurement uncertainty. Observed transients in GPS time series have led others to propose a megadetachment model, predicting that the central BRP behaves as a microplate, but with time‐varying translation. Here we reassess these hypotheses, benefiting from a significant increase in GPS stations and time span, and innovations in analysis techniques. Our results show that the BRP crust deforms everywhere and all the time. In a group of 24 stations between longitude −113.5° and −116.8°, we find strain rates of 1.9 ± 0.2 × 10−9 yr−1 extension directed N55°W and 2.2 ± 0.2 × 10−9 yr−1 contraction directed N35°E, inconsistent with microplate behavior. The linearity of time series of strain from GPS station triplets is inconsistent with episodic translation of quasi‐rigid domains. One exception is station EGAN that exhibits nonlinear motion not found in adjacent stations. The dominant signal in Nevada is distributed shear consistent with Pacific/North America relative plate motion, suggesting that stresses are transmitted through the lithosphere at least 800 km from the plate boundary. The observed active extension is consistent with earthquake focal mechanisms and is in agreement with integrated rates estimated from earthquake geology. Our results do not support the proposed megadetachment in the BRP.
Copper(I) Bromide‐Catalyzed Carbonylative Coupling of Aryl Halides with Phenols, Alcohols and Amines using Sodium Cyanide as C1 Source: A Synthesis of Carboxylic Acid Derivatives
Authors: Prasad Pragati K , Sudalai Arumugam
Published: June 2014

A new “carbon monoxide‐free” synthesis of carboxylate derivatives via carbonylative coupling of aryl bromides with phenols, alcohols, amines and acids in the presence of copper(I) bromide as catalyst and sodium cyanide in a stoichiometric amount has been developed. Its intramolecular version provides for the preparation of lactones (e.g., isochroman‐1‐ones and isobenzfuranones), imides, anhydrides and lactams in excellent yields (73–96%).

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Age and size at maturity in Indonesian women: A norm of reaction?
Authors: Sohn Kitae
Published: June 2014

Objectives

We test (McIntyre and Kacerosky's [2011]: Am J Hum Biol 23:305–312) prediction that the relationship between age at menarche and height switches from negative to positive, in a unidirectional and smooth manner, as the society industrializes. According to this prediction, a mid‐level industrial country should exhibit a weak relationship between the two variables.

Methods

The 8,013 observations are extracted from the Indonesian Family Life Survey, a nationally representative survey. Indonesia is an intermediate case that exists between the small‐scale agrarian societies and industrialized societies examined by McIntyre and Kacerosky. While age at menarche is a recalled and self‐reported variable, height is a measured one. The relationship is informally provided in a figure and formally estimated using ordinary least squares (OLS).

Results

The informal finding clearly shows no relationship between age at menarche and height. The OLS results also agree that the relationship is very weak. Specifically, despite the large sample size, the relationship is not statistically significant in a linear manner, regardless of whether the outlier group (age at menarche 10) is included or excluded. Various robustness checks are performed to confirm this finding.

Conclusions

Our results lend support to McIntyre and Kacerosky's explanation as to why the relationship between age at menarche and height switches from negative to positive as the society industrializes. Furthermore, our results imply that the model (the Day and Rowe model) and theory (life history theory) on which this explanation is based are plausible. Am. J. Hum. Biol. 26:713–715, 2014. © 2014 Wiley Periodicals, Inc.
Solvent‐Modulated Self‐Assembly of C3‐Symmetric Tris‐Urea into a Discrete Dimer and Supramolecular Gel
Authors: Shimazu Hideo , Yamanaka Masamichi
Published: June 2014

A C3‐Symmetric tris‐urea derivative self‐assembles into either a discrete dimer or a supramolecular gel via continuous assembly, depending on the solvent used. In the less polar CDCl3, the discrete dimer was selectively formed, whereas in the more polar acetonitrile and acetone, a supramolecular gel was obtained. Additionally, the gel‐sol phase transition of an acetonitrile gel of the tris‐urea derivative responds bidirectionally to chemical stimuli.
Exploring the multidimensionality of stature variation in the past through comparisons of archaeological and living populations
Authors: Vercellotti Giuseppe , Piperata Barbara A. , Agnew Amanda M. , Wilson Warren M. , Dufour Darna L. , Reina Julio C. , Boano Rosa , Justus Hedy M. , Larsen Clark Spencer , Stout Sam D. , Sciulli Paul W.
Published: June 2014

Adult stature variation is commonly attributed to differential stress‐levels during development. However, due to selective mortality and heterogeneous frailty, a population's tall stature may be more indicative of high selective pressures than of positive life conditions. This article examines stature in a biocultural context and draws parallels between bioarchaeological and living populations to explore the multidimensionality of stature variation in the past. This study investigates: 1) stature differences between archaeological populations exposed to low or high stress (inferred from skeletal indicators); 2) similarities in growth retardation patterns between archaeological and living groups; and 3) the apportionment of variance in growth outcomes at the regional level in archaeological and living populations. Anatomical stature estimates were examined in relation to skeletal stress indicators (cribra orbitalia, porotic hyperostosis, linear enamel hypoplasia) in two medieval bioarchaeological populations. Stature and biocultural information were gathered for comparative living samples from South America. Results indicate 1) significant (P < 0.01) differences in stature between groups exposed to different levels of skeletal stress; 2) greater prevalence of stunting among living groups, with similar patterns in socially stratified archaeological and modern groups; and 3) a degree of regional variance in growth outcomes consistent with that observed for highly selected traits. The relationship between early stress and growth is confounded by several factors—including catch‐up growth, cultural buffering, and social inequality. The interpretations of early life conditions based on the relationship between stress and stature should be advanced with caution. Am J Phys Anthropol 155:229–242, 2014. © 2014 Wiley Periodicals, Inc.
Thermophoresis in Nanoliter Droplets to Quantify Aptamer Binding
Authors: Seidel Susanne A. I. , Markwardt Niklas A. , Lanzmich Simon A. , Braun Dieter
Published: June 2014

Biomolecule interactions are central to pharmacology and diagnostics. These interactions can be quantified by thermophoresis, the directed molecule movement along a temperature gradient. It is sensitive to binding induced changes in size, charge, or conformation. Established capillary measurements require at least 0.5 μL per sample. We cut down sample consumption by a factor of 50, using 10 nL droplets produced with acoustic droplet robotics (Labcyte). Droplets were stabilized in an oil–surfactant mix and locally heated with an IR laser. Temperature increase, Marangoni flow, and concentration distribution were analyzed by fluorescence microscopy and numerical simulation. In 10 nL droplets, we quantified AMP‐aptamer affinity, cooperativity, and buffer dependence. Miniaturization and the 1536‐well plate format make the method high‐throughput and automation friendly. This promotes innovative applications for diagnostic assays in human serum or label‐free drug discovery screening.
Asymmetric Cascade Reaction to Allylic Sulfonamides from Allylic Alcohols by Palladium(II)/Base‐Catalyzed Rearrangement of Allylic Carbamates
Authors: Bauer Johannes Moritz , Frey Wolfgang , Peters René
Published: June 2014

A regio‐ and enantioselective tandem reaction is reported capable of directly transforming readily accessible achiral allylic alcohols into chiral sulfonyl‐protected allylic amines. The reaction is catalyzed by the cooperative action of a chiral ferrocene palladacycle and a tertiary amine base and combines high step‐economy with operational simplicity (e.g. no need for inert‐gas atmosphere or catalyst activation). Mechanistic studies support a PdII‐catalyzed [3,3] rearrangement of allylic carbamates—generated in situ from the allylic alcohol and an isocyanate—as the key step, which is followed by a decarboxylation.
Functionalization of a cyclo‐P5 Ligand by Main‐Group Element Nucleophiles
Authors: Mädl Eric , Butovskii Mikhail V. , Balázs Gábor , Peresypkina Eugenia V. , Virovets Alexander V. , Seidl Michael , Scheer Manfred
Published: June 2014

Unprecedented functionalized products with an η4‐P5 ring are obtained by the reaction of [Cp*Fe(η5‐P5)] (1; Cp*=η5‐C5Me5) with different nucleophiles. With LiCH2SiMe3 and LiNMe2, the monoanionic products [Cp*Fe(η4‐P5CH2SiMe3)]− and [Cp*Fe(η4‐P5NMe2)]−, respectively, are formed. The reaction of 1 with NaNH2 leads to the formation of the trianionic compound [{Cp*Fe(η4‐P5)}2N]3−, whereas the reaction with LiPH2 yields [Cp*Fe(η4‐P5PH2)]− as the main product, with {[Cp*Fe(η4‐P5)]2PH}2− as a byproduct. The calculated energy profile of the reactions provides a rationale for the formation of the different products.
Mapping Multivalency and Differential Affinities within Large Intrinsically Disordered Protein Complexes with Segmental Motion Analysis
Authors: Milles Sigrid , Lemke Edward A.
Published: June 2014

Intrinsically disordered proteins (IDPs) can bind to multiple interaction partners. Numerous binding regions in the IDP that act in concert through complex cooperative effects facilitate such interactions, but complicate studying IDP complexes. To address this challenge we developed a combined fluorescence correlation and time‐resolved polarization spectroscopy approach to study the binding properties of the IDP nucleoporin153 (Nup153) to nuclear transport receptors (NTRs). The detection of segmental backbone mobility of Nup153 within the unperturbed complex provided a readout of local, region‐specific binding properties that are usually masked in measurements of the whole IDP. The binding affinities of functionally and structurally diverse NTRs to distinct regions of Nup153 can differ by orders of magnitudes—a result with implications for the diversity of transport routes in nucleocytoplasmic transport.
Oil resistance and mechanical properties of polysiloxane nanocomposites prepared by in situ reaction of reactive polar monomers
Authors: Meng Yang , Chu Junfeng , Liu Chaohao , Wei Zheng , Zhang Liqun
Published: June 2014

A series of poly(methylvinylsiloxane) elastomer (VMQ) composites with improved oil resistance were prepared by introducing uniform polar polymer phases into VMQ matrix through the in situ reaction of reactive polar monomers—hydroxyethyl methacrylate (HEMA) and hydroxypropyl methacrylate (HPMA)—during peroxide curing. Differential scanning calorimetry and Fourier transform infrared measurements demonstrated that HEMA and HPMA had high reactivity and most of the monomers participated in the in situ reaction during peroxide curing. Transmission electron microscopic images showed that the uniform nanophases with the diameters in the range of 20–50 nm formed in the VMQ vulcanizates. The generated nanophases could interact with silica to form a strong filler network in the VMQ matrix, resulting in a significant increase of the modulus at low elongation of the VMQ vulcanizates. With increasing the content of polar monomers, the tensile strength decreased slightly, the elongation at break, the hardness and the 100% modulus increased, but the 300% modulus decreased significantly due to the decrease of the crosslink density. The incorporation of HEMA or HPMA into VMQ matrix could significantly improve the oil resistance of polysiloxane elastomer, and the oil resistance of the composites containing HEMA was a little better than that of the composites containing HPMA. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40983.
Australia's ‘Pacific Solution’: Issues for the Pacific Islands
Authors: Warbrooke Aulden
Published: June 2014

In 2013, the Rudd Labor Government introduced a new version of the ‘Pacific Solution’ to Australia's ‘problem’ with increasing numbers of asylum‐seekers arriving by boat. The new version not only included the transfer of asylum‐seekers to Nauru and Manus Island in Papua New Guinea, it crucially involved the resettlement in these Pacific Island countries of those found to be refugees and introduces long‐term detention for those who are not successful and who do not decide to return to their original countries. Following the 2013 election, the Abbott Coalition Government fully embraced the new ‘Pacific Solution’. This deeper level of incorporation of Papua New Guinea and Nauru in Australia's asylum‐seeker policy raises a range of issues not only for these two Pacific Island countries but also for the broader Pacific islands region whose name is invoked in the ‘Pacific Solution’.
Regulation of synovial cell growth: Coexpression of transforming growth factor β and basic fibroblast growth factor by cultured synovial cells
Authors: Goddard David H. , Grossman Scott L. , Williams William V. , Weiner David B. , Gross Janet L. , Eidsvoog Kristi , Dasch James R.
Published: June 2014

Objective. To demonstrate expression of transforming growth factor β (TGFβ) and basic fibroblast growth factor (bFGF) by cultured rheumatoid arthritis (RA) synovial cells and to investigate their role as synovial cell mitogens.

Methods. Polypeptide growth factors were detected and identified by immunocytochemical staining and Western blot analysis. Messenger RNA (mRNA) transcripts encoding TGFβ and bFGF were identified by polymerase chain reaction analysis. The influence of neutralizing growth factor monoclonal antibodies (MAb) on RA synovial cell growth was investigated. TGFβ bioactivity was determined by Mv1Lu assay.

Results. Lysates of RA, as compared with normal, synovial cells contained greater amounts of TGFβ and bFGF. Western blot analysis identified a single TGFβ band (MW ˜25 kd) in each of the cell lysates examined. Western blot analysis using MAb DE6 identified a doublet of bFGF bands (MW ˜18.0 kd) in normal synovial cell lysates and 4 bFGF bands (MW ˜18.0, 22.0, 22.6, and 25.2 kd) in RA synovial cell lysates. RA and normal synovial cells expressed mRNA transcripts encoding TGFβ1 but not TGFβ2, and FGF‐2 (basic FGF). Additional mRNA transcripts encoding FGF‐5 and FGF‐7 were expressed by RA, but not normal, synovial cells in culture. In contrast to MAb 1D11.16, which caused a dose‐dependent decrease in RA synovial cell growth, MAb DG2 (up to 100 μg/ml) had no effect on cell growth.

Conclusion. RA and normal synovial cells cultured in serum‐free medium express TGFβ1 and native bFGF. However, only RA synovial cells in culture express higher molecular weight isoforms of bFGF. TGFβ1 appears to regulate synovial cell growth in vitro through an external autocrine loop. Despite expression of high‐affinity bFGF receptors on cultured synovial cells, the mechanisms by which bFGF modulates synovial cell growth are unknown.
Quantitation of chondroitin 4—sulfate and chondroitin 6—sulfate in pathologic joint fluid
Authors: Shinmei Masayuki , Miyauchi Satoshi , Machida Akemi , Miyazaki Kyosuke
Published: June 2014

Objective. To investigate the correlation between joint disease and the composition of chondroitin sulfate in the joint fluid, unsaturated disaccharide isomers of chondroitin 4—sulfate (Δdi‐4S) and chondroitin 6—sulfate (Δdi‐6S) were measured in joint fluids obtained from patients with osteoarthritis (OA), rheumatoid arthritis (RA), or traumatic arthritis (TA).

Methods. These pathologic joint fluids were digested with chondroitinase ABC, and the Δdi‐4S and Δdi‐6S produced were determined by high performance liquid chromatography combined with fluorometry.

Results. Total content of Δdi‐4S plus Δdi‐6S was 71.8 ± 30.0 nmoles/ml (mean ± SD) in OA, 55.4 ± 29.3 nmoles/ml in RA, and 211 ± 149 nmoles/ml in TA joint fluids. The ratio of Δdi‐6S to Δdi‐4S was 3.81 ± 0.992 in OA, 1.13 ± 0.527 in RA, and 5.75 ± 2.46 in TA joint fluids. Differences between groups were statistically significant.

Conclusion. These results strongly suggest that the levels of chondroitin sulfate isomers and the Δdi‐6S: Δdi‐4S ratio in joint fluid reflect the proteoglycan metabolism of joint tissues, particularly of articular cartilage; hence, they could be used to diagnose joint diseases and to predict articular cartilage destruction from such joint diseases.
Mining browsing behaviors for objectionable content filtering
Authors: Lee Lung‐Hao , Juan Yen‐Cheng , Tseng Wei‐Lin , Chen Hsin‐Hsi , Tseng Yuen‐Hsien
Published: June 2014

This article explores users' browsing intents to predict the category of a user's next access during web surfing and applies the results to filter objectionable content, such as pornography, gambling, violence, and drugs. Users' access trails in terms of category sequences in click‐through data are employed to mine users' web browsing behaviors. Contextual relationships of URL categories are learned by the hidden Markov model. The top‐level domains (TLDs) extracted from URLs themselves and the corresponding categories are caught by the TLD model. Given a URL to be predicted, its TLD and current context are empirically combined in an aggregation model. In addition to the uses of the current context, the predictions of the URL accessed previously in different contexts by various users are also considered by majority rule to improve the aggregation model. Large‐scale experiments show that the advanced aggregation approach achieves promising performance while maintaining an acceptably low false positive rate. Different strategies are introduced to integrate the model with the blacklist it generates for filtering objectionable web pages without analyzing their content. In practice, this is complementary to the existing content analysis from users' behavioral perspectives.
Classical databases and knowledge organization: A case for boolean retrieval and human decision‐making during searches
Authors: Hjørland Birger
Published: June 2014

This paper considers classical bibliographic databases based on the Boolean retrieval model (such as MEDLINE and PsycInfo). This model is challenged by modern search engines and information retrieval (IR) researchers, who often consider Boolean retrieval a less efficient approach. The paper examines this claim and argues for the continued value of Boolean systems, and suggests two further considerations: (a) the important role of human expertise in searching (expert searchers and “information literate” users) and (b) the role of library and information science and knowledge organization (KO) in the design and use of classical databases. An underlying issue is the kind of retrieval system for which one should aim. Warner's (2010) differentiation between the computer science traditions and an older library‐oriented tradition seems important; the former aim to transform queries automatically into (ranked) sets of relevant documents, whereas the latter aims to increase the “selection power” of users. The Boolean retrieval model is valuable in providing users with the power to make informed searches and have full control over what is found and what is not. These issues may have significant implications for the maintenance of information science and KO as research fields as well as for the information profession as a profession in its own right.
Peptide p160‐Coated Silica Nanoparticles Applied in Photodynamic Therapy
Authors: Yang Yang , Wang Anhe , Jia Yi , Brezesinski Gerald , Dai Luru , Zhao Jie , Li Junbai
Published: June 2014

Peptide p160‐conjugated mesoporous silica nanoparticles (MSN) were fabricated and loaded with photosensitizer hypocrellin B (HB). The results indicate that the nanocomposites have better selectivity for cancer cells and higher cytotoxicity in photodynamic therapy in vitro. The nanocomposites can be used as a novel candidate in photodynamic therapy. This may be a general and promising method to modify nanoparticles to improve their cell affinity.
Programmable Design of Functional Ribonucleoprotein Complexes
Authors: Rath Anna K. , Kellermann Stefanie J. , Rentmeister Andrea
Published: June 2014

Ribonucleoprotein (RNP) complexes are widespread in nature and play crucial roles in gene regulation, RNA processing, and translation. Novel technologies, such as CRISPR‐mediated genome engineering, stress the potential of RNP complexes to carry out complex tasks in molecular biology. Here we report a bottom‐up approach for the programmable self‐assembly of RNP complexes. The building blocks for RNP complex formation are RNAs and Pumilio proteins that can bind to RNA sequence‐specifically. Correct RNP assembly triggers protein complementation of a tripartite GFP, thereby resulting in up to 25‐fold increased fluorescence, and is strictly dependent on the correct RNA sequences. Our results indicate that Pumilio and guide RNAs are suitable building blocks for the correct self‐assembly of RNP complexes consisting of up to six different components. Self‐assembling RNP complexes might prove useful for complex biotechnological applications in RNA sensing, imaging, or processing.
Effect of the Bulkiness of the End Functional Amide Groups on the Optical, Gelation, and Morphological Properties of Oligo(p‐phenylenevinylene) π‐Gelators
Authors: Babu Sukumaran Santhosh , Praveen Vakayil K. , Kartha Kalathil K. , Mahesh Sankarapillai , Ajayaghosh Ayyappanpillai
Published: June 2014

Herein, we describe the role of end functional groups in the self‐assembly of amide‐functionalized oligo(p‐phenylenevinylene) (OPV) gelators with different end‐groups. The interplay between hydrogen‐bonding and π‐stacking interactions was controlled by the bulkiness of the end functional groups, thereby resulting in aggregates of different types, which led to the gelation of a wide range of solvents. The variable‐temperature UV/Vis absorption and fluorescence spectroscopic features of gelators with small end‐groups revealed the formation of 1D H‐type aggregates in CHCl3. However, under fast cooling in toluene, 1D H‐type aggregates were formed, whereas slow cooling resulted in 2D H‐type aggregates. OPV amide with bulky dendritic end‐group formed hydrogen‐bonded random aggregates in toluene and a morphology transition from vesicles into fibrous aggregates was observed in THF. Interestingly, the presence of bulky end‐group enhanced fluorescence in the xerogel state and aggregation in polar solvents. The difference between the aggregation properties of OPV amides with small and bulky end‐groups allowed the preparation of self‐assembled structures with distinct morphological and optical features.
The Microwave‐Assisted Ionic‐Liquid Method: A Promising Methodology in Nanomaterials
Authors: Ma Ming‐Guo , Zhu Jie‐Fang , Zhu Ying‐Jie , Sun Run‐Cang
Published: June 2014

In recent years, the microwave‐assisted ionic‐liquid method has been accepted as a promising methodology for the preparation of nanomaterials and cellulose‐based nanocomposites. Applications of this method in the preparation of cellulose‐based nanocomposites comply with the major principles of green chemistry, that is, they use an environmentally friendly method in environmentally preferable solvents to make use of renewable materials. This minireview focuses on the recent development of the synthesis of nanomaterials and cellulose‐based nanocomposites by means of the microwave‐assisted ionic‐liquid method. We first discuss the preparation of nanomaterials including noble metals, metal oxides, complex metal oxides, metal sulfides, and other nanomaterials by means of this method. Then we provide an overview of the synthesis of cellulose‐based nanocomposites by using this method. The emphasis is on the synthesis, microstructure, and properties of nanostructured materials obtained through this methodology. Our recent research on nanomaterials and cellulose‐based nanocomposites by this rapid method is summarized. In addition, the formation mechanisms involved in the microwave‐assisted ionic‐liquid synthesis of nanostructured materials are discussed briefly. Finally, the future perspectives of this methodology in the synthesis of nanostructured materials are proposed.
Electrospun meshes possessing region‐wise differences in fiber orientation, diameter, chemistry and mechanical properties for engineering bone‐ligament‐bone tissues
Authors: Samavedi Satyavrata , Vaidya Prasad , Gaddam Prudhvidhar , Whittington Abby R. , Goldstein Aaron S.
Published: June 2014

Although bone‐patellar tendon‐bone (B‐PT‐B) autografts are the gold standard for repair of anterior cruciate ligament ruptures, they suffer from drawbacks such as donor site morbidity and limited supply. Engineered tissues modeled after B‐PT‐B autografts are promising alternatives because they have the potential to regenerate connective tissue and facilitate osseointegration. Towards the long‐term goal of regenerating ligaments and their bony insertions, the objective of this study was to construct 2D meshes and 3D cylindrical composite scaffolds – possessing simultaneous region‐wise differences in fiber orientation, diameter, chemistry and mechanical properties – by electrospinning two different polymers from off‐set spinnerets. Using a dual drum collector, 2D meshes consisting of an aligned polycaprolactone (PCL) fiber region, randomly oriented poly(lactide‐co‐glycolide) (PLGA) fiber region and a transition region (comprised of both PCL and PLGA fibers) were prepared, and region‐wise differences were confirmed by microscopy and tensile testing. Bone marrow stromal cells (BMSCs) cultured on these meshes exhibited random orientations and low aspect ratios on the random PLGA regions, and high aspect ratios and alignment on the aligned PCL regions. Next, meshes containing an aligned PCL region flanked by two transition regions and two randomly oriented PLGA regions were prepared and processed into 3D cylindrical composite scaffolds using an interpenetrating photo‐crosslinkable polyethylene glycol diacrylate hydrogel to recapitulate the shape of B‐PT‐B autografts. Tensile testing indicated that cylindrical composites were mechanically robust, and eventually failed due to stress concentration in the aligned PCL region. In summary, this study demonstrates a process to fabricate electrospun meshes possessing region‐wise differences in properties that can elicit region‐dependent cell responses, and be readily processed into scaffolds with the shape of B‐PT‐B autografts. Biotechnol. Bioeng. 2014;111: 2549–2559. © 2014 Wiley Periodicals, Inc.
Amorfrutins: A Promising Class of Natural Products that Are Beneficial to Health
Authors: Sauer Sascha
Published: June 2014

The incidence of complex noncommunicable diseases has strongly increased over the last several decades in the US, Europe and other parts of the world that have adopted a western lifestyle (M. Ezzati, E. Riboli, Science­ 2012, 337, 1482–1487; S. Smyth, A. Heron, Nat. Med.­ 2006, 12, 75). Despite considerable investment in the development of new types of drugs, options for the treatment of many common diseases remain inadequate. If current trends prevail, the rising incidence of disorders such as obesity and type 2 diabetes mellitus (T2DM) will soon result in an unsustainable burden on society (World Health Organization Technical Report Series­ 2000, 894, i–xii, 1–253). Given the difficulty of treating fully developed complex disorders, new strategies for early intervention and prevention of common diseases are of great interest. Dietary natural products with beneficial effects, such as the recently described antidiabetic and lipid‐lowering amorfrutins, could pave the way for efficiently treating and preventing metabolic and other complex diseases (C. Weidner, et al. Proc. Natl. Acad. Sci. USA­ 2012, 109, 7257–7262).
Self‐Assembly of Amyloid Fibrils That Display Active Enzymes
Authors: Zhou Xiao‐Ming , Entwistle Aiman , Zhang Hong , Jackson Antony P. , Mason Thomas O. , Shimanovich Ulyana , Knowles Tuomas P. J. , Smith Andrew T. , Sawyer Elizabeth B. , Perrett Sarah
Published: June 2014

Enzyme immobilization is an important strategy to enhance the stability and recoverability of enzymes and to facilitate the separation of enzymes from reaction products. However, enzyme purification followed by separate chemical steps to allow immobilization on a solid support reduces the efficiency and yield of the active enzyme. Here we describe polypeptide constructs that self‐assemble spontaneously into nanofibrils with fused active enzyme subunits displayed on the amyloid fibril surface. We measured the steady‐state kinetic parameters for the appended enzymes in situ within fibrils and compare these with the identical protein constructs in solution. Finally, we demonstrated that the fibrils can be recycled and reused in functional assays both in conventional batch processes and in a continuous‐flow microreactor.
Optimization of a Mixed Additive and its Effect on Physicochemical Properties of Bio‐Oil
Authors: Zhang Le , Liu Ronghou , Yin Renzhan , Mei Yuanfei , Cai Junmeng
Published: June 2014

A final optimal mixed additive consisting of methanol, acetone, and ethyl acetate in specific proportions was obtained by one‐factor multi‐objective optimization of the Design‐Expert software and performed well in a verification experiment. The mixed additive of methanol and ethyl acetate was first prepared separately and then added to bio‐oil, followed by acetone. The viscosity of the additive/bio‐oil mixture was significantly lower than of the crude bio‐oil. Among all chemical compound groups in the bio‐oil, the content of phenols was the highest one. Chemical compounds in bio‐oil after aging had higher molecular mass weights than before. The addition of the final optimal mixed additive and the accelerated aging process could slightly change the intensity and positions of some absorption peaks.
Hydrodynamic Behavior and Residence Time Distribution of Industrial‐Scale Bale Packings
Authors: Ding Huidian , Xiang Wenyu , Song Ning , Liu Chunjiang , Yuan Xigang
Published: June 2014

The hydrodynamic behavior of bale packing was tested in a catalytic distillation column. Models and empirical equations for predicting pressure drop and dynamic liquid holdup were proposed and compared with experimental results. The examination of residence time distribution (RTD) relied on the pulse method and a conductivity meter which deduced the axial Péclet number, axial dispersion coefficient, and dynamic liquid holdup. The relations of dynamic liquid holdup obtained from gravimetric draining experiments and RTD studies were discussed with static and total liquid holdup. Potential impacts of the liquid distributor and conductivity cell were also assessed. The results prove that models and empirical equations fit well and are reliable in design and scale‐up.
X‐ray Crystal Structure Analysis of Sodium‐Ion Conductivity in 94 Na3PS4⋅6 Na4SiS4 Glass‐Ceramic Electrolytes
Authors: Tanibata Naoto , Noi Kousuke , Hayashi Akitoshi , Kitamura Naoto , Idemoto Yasushi , Tatsumisago Masahiro
Published: June 2014

Rietveld analysis of cubic Na3PS4 in the 94 Na3PS4⋅6 Na4SiS4 (mol %) glass ceramic indicates that two Na+ sites (Na1 and Na2) can be found in cubic Na3PS4 and that the phosphorus atoms in cubic Na3PS4 are partially replaced by silicon in the 94 Na3PS4⋅6 Na4SiS4 glass ceramic. The electron‐density distribution of the cubic Na3PS4 structure, obtained by the maximum‐entropy method/Rietveld method, revealed that cubic Na3PS4 contains three‐dimensional Na+ conduction pathways along the Na1 and Na2 sites. From the Rietveld analysis, the cubic Na3PS4 in the 94 Na3PS4⋅6 Na4SiS4 glass ceramic has a larger site‐occupancy of Na2 than that in the Na3PS4 glass ceramic, which may be responsible for the improvement in Na+ conductivity.
How Does the Choice of Anode Material Influence Electrical Performance? A Comparison of Two Microbial Fuel Cell Model Organisms
Authors: Kipf Elena , Zengerle Roland , Gescher Johannes , Kerzenmacher Sven
Published: June 2014

The influence of the anode material on the electrical performance of the two microbial fuel cell model organisms Geobacter sulfurreducens and Shewanella oneidensis is investigated. High‐surface‐area activated carbon and low‐surface‐area graphite felt are compared in terms of polarization curves under quasi‐steady‐state conditions. Unexpectedly, G. sulfurreducens exhibits similar current densities up to 700 μA cm−2 independent of the anode material. This is ∼50 % higher than steady‐state values reported previously. The negligible influence of electrode material on the electrical performance of G. sulfurreducens is attributed to the fact that it performs only direct electron transfer, but forms thick biofilms. In contrast, S. oneidensis, relying mainly on mediated electron transfer, apparently makes better use of high‐surface‐area activated carbon and achieves higher current densities compared to graphite felt. This underlines the importance of tailoring anode materials according to the used organisms.
Topographic specializations in the retinal ganglion cell layer correlate with lateralized visual behavior, ecology, and evolution in cockatoos
Authors: Coimbra João Paulo , Collin Shaun P. , Hart Nathan S.
Published: May 2014

Cockatoos are a unique avian group inhabiting a diversity of arboreal and terrestrial microhabitats. Most species display strong lateralized visual behaviors using their left eye/foot to assist with food manipulation during foraging. In this study, we used retinal wholemounts and stereological methods to investigate whether the topographic distribution of retinal ganglion cells in cockatoos reflects their lateralized behaviors and microhabitat diversity. We found that all species studied possess a horizontal visual streak and a shallow central fovea that afford increased spatial resolution in the lateral visual field. Arboreal cockatoos have a well‐defined dorsotemporal area, in contrast to terrestrial cockatoos, in which this specialization is inconspicuous or absent. Terrestrial cockatoos also have a triangular extension of increased ganglion cell density directed toward the dorsotemporal retinal periphery. Both the dorsotemporal area and the triangular extension enhance spatial resolution in the frontal and inferior visual fields, which potentially assists with binocular coordination during foraging. We found significantly higher ganglion cell densities in the left (52,000–72,000 cells/mm2) compared with the right (42,500–50,000 cells/mm2) perifoveal region of species that have strong left eye–left foot lateralized behaviors. In contrast, cockatoo species that show no lateralized behaviors have equivalent retinal ganglion cell densities in both left and right perifoveal regions (42,500–52,500 cells/mm2). Retinal ganglion cell peak densities in the dorsotemporal area showed no significant difference between left and right eyes for any species, suggesting that cockatoos use both eyes to extract information in the binocular visual field, independent of the degree of lateralization. J. Comp. Neurol. 522:3363–3385, 2014. © 2014 Wiley Periodicals, Inc.
Polyoxometalate‐Based Metal–Organic Frameworks as Catalysts for the Selective Oxidation of Alcohols in Micellar Systems
Authors: Zhu Jie , Shen Meng‐nan , Zhao Xue‐jing , Wang Peng‐cheng , Lu Ming
Published: June 2014

A series of nanosized metal–organic frameworks (MOFs) encapsulating different polyoxometalates (POMs) including H3PW4O12, H5PMo12O40, H5PVMo10O40, H5PV2Mo10O40, and H5PV3Mo10O40 was synthesized and used in the selective oxidation of alcohols. The catalyst with a uniform size and morphology offered easy accessibility between substrates and catalyst. At the same time, the MOF ensured that the POM was encapsulated, which could dramatically prevent the assembly of the catalyst. Furthermore, the catalyst showed clear chemoselectivity, which was related to the size or accessibility of the substrates for surface pores. With cetyltrimethyl ammonium bromide aqueous solution as solvent, both improved reaction efficiency and simple recycling of the catalytic system were achieved to afford a green oxidation process.
The plexin C1 receptor promotes acute inflammation
Authors: König Klemens , Marth Linda , Roissant Jan , Granja Tiago , Jennewein Carla , Devanathan Vasudharani , Schneider Mariella , Köhler David , Zarbock Alexander , Rosenberger Peter
Published: May 2014

Acute inflammation is the pathophysiological basis of important clinical conditions associated with organ failure. The initial inflammatory response is controlled by the chemokine system, yet recent data have indicated that the neuronal guidance cues are significantly involved in the orchestration of this process. Previous work has shown the proinflammatory capacity of the guidance cue semaphorin (Sema) 7a, but the role of one of its target receptors, the plexin C1 (PLXNC1) receptor is to date unknown. We report here that PLXNC1 is expressed outside the nervous system and induced during acute inflammation. PLXNC1−/− mice with C57BL/6 background demonstrated decreased inflammatory responses during zymosan A (ZyA)‐induced peritonitis. Subsequent in vivo studies revealed altered rolling, adhesion, and transmigration properties of PLXNC1−/− leukocytes. Blockade of PLXNC1 was associated with attenuated chemotactic transendothelial migration properties in vitro. Studies in chimeric mice revealed that hematopoietic PLXNC1−/− animals demonstrated an attenuated inflammatory response. To probe the therapeutic potential of PLXNC1 we treated C57BL/6 WT mice with an anti‐PLXNC1 antibody and a PLXNC1 binding peptide. Both of these interventions significantly dampened ZyA‐induced peritonitis. These results implicate an important role of PLXNC1 during an acute inflammatory response and indicate PLXNC1 as a potential target for the control of conditions associated with acute inflammation.
Cyclodextrin‐mediated enantioseparation of phenylalanine amide derivatives and amino alcohols by capillary electrophoresis—Role of complexation constants and complex mobilities
Authors: Aranyi Anita , Péter Antal , Ilisz István , Fülöp Ferenc , Scriba Gerhard K. E.
Published: May 2014

The separation of the enantiomers of phenylalanine amide and N‐methyl derivatives as well as some amino alcohols was studied by CE in acidic BGEs using CDs as chiral selectors. The native CDs displayed only low chiral recognition ability at a concentration of 15 mg/mL in 20 mM sodium phosphate buffer, pH 2.5. In contrast, the analyte enantiomers were separated in the presence of randomly sulfated CDs under reversed polarity of the applied voltage. Sulfated β‐CD proved to be the most universal selector resulting in the enantioseparation of all analytes. Opposite enantiomer migration order depending on the size of the CD cavity was observed for phenylalanine amide and 2‐amino‐2‐phenylethanol. The R‐enantiomers migrated first in the presence of sulfated α‐CD and γ‐CD while the S‐enantiomers were detected first in the presence of sulfated β‐CD. The enantioseparations could be rationalized based on analyte complexation by the respective CDs except for 2‐amino‐2‐phenylethanol and sulfated β‐CD where essentially equal complexation constants were derived for the enantiomers. In this case, the migration behavior could be attributed to the mobilities of the enantiomer–CD complexes adding another example to the CE‐specific phenomenon of enantioseparations based primarily on complex mobilities.
Properties of modern dust accumulating in the Uinta Mountains, Utah, USA, and implications for the regional dust system of the Rocky Mountains
Authors: Munroe Jeffrey S.
Published: May 2014

A growing body of work is illuminating the importance of dust as a component of soil development and biogeochemical cycling in alpine environments of the Rocky Mountains. Nonetheless, important questions remain about the dust system in this region due to a paucity of focused studies and direct measurements. This project involved deployment of modified marble dust traps in the alpine zone of the Uinta Mountains of Utah to trap modern atmospheric dust over a two year period. Results indicate that dust accumulation rates are similar to values previously reported for the Wind River Range of Wyoming, but less than values for south‐western Colorado, suggesting a south‐to‐north decrease in regional dust flux. The overall mean grain size of Uinta dust is similar to values reported by prior studies in Colorado, indicating a general uniformity in grain size distribution. Uinta dust is dominated by quartz, plagioclase, K‐feldspar, and illite with trace amounts of kaolinite, chlorite, and amphibole. In contrast, only quartz and K‐feldspar are present in the Uinta bedrock, confirming an exotic origin for the dust arriving in the alpine zone. Exotic mineralogies have also been reported in dust from other mountain ranges in the western United States, indicating that eolian delivery of allochthonous minerals is a widespread process. Geochemical analysis reveals that Bi, Na, P, Zn, Sn, Cu, Cd, Ba, Ni, W, Sb, Pb, and Tl in Uinta dust are elevated 10 to > 80‐times above their abundances in local bedrock. These results support reports of anthropogenic elemental enrichment in lake sediments from Colorado and Utah. Patterns of elemental loading suggest that certain elements are delivered by winds arriving from different directions, raising the possibility that some elements could be associated with unique source areas. Copyright © 2014 John Wiley & Sons, Ltd.