bluuebunny/crossref_metadata_2025 huggingface dataset:
Electrospun antibacterial nanofibers: Production, activity, andin vivoapplications
Authors: Gao Yuan , Bach Truong Yen , Zhu Yonggang , Louis Kyratzis Ilias
Published: April 2014

Electrospinning is an economical and relatively simple method to produce continuous and uniform nanofibers from almost any synthetic and many natural polymers. Because of the high specific surface area, tunable pore size, and flexibility, the nanofibrous membranes are finding an increasingly wide range of applications. Some particular attention has been devoted to antibacterial nanofibers for applications such as wound dressings. A variety of biocides, e.g.,antibiotics, quaternary ammonium salts, triclosan, biguanides, (silver, titanium dioxide, and zinc oxide) nanoparticles and chitosan have been incorporated by various techniques into nanofibers that exhibit strong antibacterial activity in standard assays. However, the small diameters of the nanofibers also mean that the incorporated biocides are often burst released once the materials are submerged in an aqueous solution. Nevertheless, several strategies, such as core‐sheath structure of the nanofiber, covalent bonding of the biocide on the fiber surface and adsorption of the biocide in nanostructures, can be utilized to sustain the release over several days. This review summarizes recent development in the fabrication of antibacterial nanofibers, the release profiles of the biocides and their applications inin vivosystems. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2014,131, 40797.
Strength improvements in toughened epoxy composites using surface treated GnPs
Authors: Zaldivar Rafael J. , Adams Paul M. , Kim Hyun I. , Nokes James P. , Patel Dhruv N.
Published: April 2014

Nanographitic materials are gaining enormous interest as a new class of reinforcement for nanocomposites, promising revolutionary electrical, thermal, and mechanical properties. However, the progress has been quite limited especially in terms of mechanical properties. Here we report a significant leap, >2× increases in tensile strength and modulus of an epoxy composite using surface treated graphite nanoplatelets (GnPs). This corroborated by increases in Tgs as well as the presence of oxygen‐functionalized groups verified by XPS, suggest improved distribution and chemical interaction at the filler‐to‐matrix interface. Toughness values also showed increases with concentration, without compromising the strength or failure strain. However, if solvent levels during degassing were not reduced sufficiently, negligible contributions to strength and stiffness were observed with GnP loading. Subsequent elevated temperature treatments increased the strength of the composite due to cure enhancement of the matrix material, yet did not provide mechanical enhancements due to the incorporation of the filler. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40802.
Zein film: Effects of dielectric barrier discharge atmospheric cold plasma
Authors: Pankaj S. K. , Bueno‐Ferrer Carmen , Misra N. N. , Bourke Paula , Cullen P. J.
Published: April 2014

Dielectric barrier discharge atmospheric plasma is a novel nonthermal technology for the food and packaging industry. The effects of dielectric barrier discharge plasma on the surface, structural, thermal, and moisture sorption properties of edible zein films have been examined. Plasma treatment increased the surface roughness and equillibrium moisture content of the zein film in a direct relationship with the applied voltage level. No significant difference in the thermal stability of the zein film is also observed after plasma treatment. Dielectric barrier discharge plasma treatments of zein film lead to a change in the protein conformation which is confirmed by X‐ray diffraction and Fourier transform Infrared spectroscopy. The evaluation of films modifications by plasma discharge will contribute to enhance the in‐package decontamination studies of food products by plasma. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40803.
CO2 gas barrier properties in polymer nanocomposite coatings containing Li‐hectorite clays
Authors: Choudalakis Georgios A. , Kalo Hussein , Breu Josef , Gotsis Alexandros D.
Published: April 2014

This is a study of the addition of hydrophilic Li‐hectorite nanoplatelets in waterborne acrylic resin emulsions and the resulting nanocomposite coatings. The mechanism of the dispersion of the nanoplatelets during film formation and curing from aqueous suspensions is described. The morphological features of the coating and the state of delamination is examined via X‐ray diffraction for three different clay treatment procedures. The influence of the shape of the nanosized objects and their dispersion level on the transport characteristics of the nanocomposite film are measured and their effect on the polymer free volume is discussed. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40805.
Clinical Characteristics and Treatment Outcomes of Autoimmune‐Associated Hemophagocytic Syndrome in Adults
Authors: Kumakura Shunichi , Murakawa Yohko
Published: April 2014

Objective

To better define the clinical characteristics and treatment outcomes of autoimmune‐associated hemophagocytic syndrome (AAHS) in adults.

Methods

Adults with AAHS (defined as pathologic evidence of hemophagocytosis without any obvious cause other than an autoimmune disease) were identified through a review of the literature.

Results

Among 116 patients identified, underlying diseases included systemic lupus erythematosus (SLE) in 52.3%, adult‐onset Still's disease (AOSD) in 26.7%, and dermatomyositis in 6.9%. Fever, lymphadenopathy, hepatomegaly, and splenomegaly were found in 86.8%, 41.0%, 41.8%, and 45.5% of patients, respectively. Cytopenia, liver dysfunction, and hyperferritinemia developed frequently, and coagulopathy was seen in 50.6% of patients. Normal or low C‐reactive protein levels were characteristic of patients with underlying SLE. The most commonly used therapy was corticosteroids, which were initially administered in 95.7% of patients, with 57.7% responding. Patients with corticosteroid‐refractory disease were usually treated with cyclosporine, intravenous cyclophosphamide (IV CYC), or intravenous immunoglobulin (IVIG), with IV CYC being highly effective. Treatment with biologic agents resulted in favorable effects in the majority of patients. The mortality rate was 12.9%. Male sex (odds ratio [OR] 6.47, 95% confidence interval [95% CI] 2.06–30.39, P < 0.01), dermatomyositis (OR 5.57, 95% CI 1.08–28.65, P < 0.05), and anemia (hemoglobin <8 gm/dl; OR 3.74, 95% CI 1.02–13.8, P < 0.05) were identified as factors associated with mortality.

Conclusion

AAHS is potentially fatal. Corticosteroids are a mainstay of initial treatment. For corticosteroid‐refractory disease, IV CYC may be beneficial as compared with cyclosporine or IVIG. Treatment that proceeds directly from corticosteroids to biologic agents is promising.
Glycogen Synthase Kinase 3 Inhibition Stimulates Human Cartilage Destruction and Exacerbates Murine Osteoarthritis
Authors: Litherland Gary J. , Hui Wang , Elias Martina S. , Wilkinson David J. , Watson Sharon , Huesa Carmen , Young David A. , Rowan Andrew D.
Published: April 2014

Objective

To assess the role of glycogen synthase kinase 3 (GSK‐3) as a regulator of cartilage destruction in human tissue and a murine model of osteoarthritis (OA).

Methods

Surgical destabilization of the medial meniscus (DMM) was performed to induce experimental murine OA, and joint damage was assessed histologically. Bovine nasal and human OA cartilage samples were incubated with interleukin‐1 (IL‐1) plus oncostatin M (OSM) and GSK‐3 inhibitor. Collagen and proteoglycan release was assessed by hydroxyproline measurement and dye binding assay, collagenase activity was assessed by bioassay, and gene expression was analyzed by real‐time polymerase chain reaction. Human articular chondrocytes were isolated by enzymatic digestion and cultured prior to gene silencing and immunoblotting of cell lysates and nuclear fractions.

Results

Mice treated with GSK‐3 inhibitor exhibited significantly greater cartilage damage compared with sham‐operated control mice. GSK‐3 inhibition in bovine cartilage dramatically accelerated IL‐1 plus OSM–stimulated degradation, concomitant with a profound increase in collagenase activity. GSK‐3 inhibitor induced collagen release from human OA cartilage in the presence of IL‐1 plus OSM and increased proteoglycan loss. Gene expression profiling of resorbing OA cartilage revealed a marked procatabolic switch in gene expression upon GSK‐3 inhibition. This was mirrored in human articular chondrocytes following GSK3 silencing, particularly with the GSK‐3β isoform. GSK‐3 inhibition or silencing led to enhanced IL‐1 plus OSM–stimulated abundance and activity of Jun, and silencing of c‐jun ameliorated GSK‐3 inhibitor–mediated procatabolic gene expression.

Conclusion

GSK‐3 is an important regulator of matrix metalloproteinase (MMP)–mediated joint destruction, the inhibition of which by proinflammatory stimuli de‐represses catabolic gene expression. Therapeutic strategies that maintain cartilage GSK‐3 activity may therefore help curtail aberrant MMP activity during pathologic joint destruction.
Student perceptions and effectiveness of an innovative learning tool: Anatomy Glove Learning System
Authors: Lisk Kristina , McKee Pat , Baskwill Amanda , Agur Anne M.R.
Published: April 2014

A trend in anatomical education is the development of alternative pedagogical approaches to replace or complement experiences in a cadaver laboratory; however, empirical evidence on their effectiveness is often not reported. This study aimed to evaluate the effectiveness of Anatomy Glove Learning System (AGLS), which enables students to learn the relationship between hand structure and function by drawing the structures onto a worn glove with imprinted bones. Massage therapy students (n = 73) were allocated into two groups and drew muscles onto either: (1) the glove using AGLS instructional videos (3D group); or (2) paper with palmar/dorsal views of hand bones during an instructor‐guided activity (2D group). A self‐confidence measure and knowledge test were completed before, immediately after, and one‐week following the learning conditions. Self‐confidence of hand anatomy in the 3D group gradually increased (3.2/10, 4.7/10, and 4.8/10), whereas self‐confidence in the 2D group began to decline one‐week later (3.2/10, 4.4/10, and 3.9/10). Knowledge of hand anatomy improved in both groups immediately after learning, (P < 0.001). Students' perceptions of AGLS were also assessed using a 10‐pt Likert scale evaluation questionnaire (10 = high). Students perceived the AGLS videos (mean = 8.3 ± 2.0) and glove (mean = 8.1 ± 1.8) to be helpful in improving their understanding of hand anatomy and the majority of students preferred AGLS as a learning tool (mean = 8.6 ± 2.2). This study provides evidence demonstrating that AGLS and the traditional 2D learning approach are equally effective in promoting students' self‐confidence and knowledge of hand anatomy. Anat Sci Educ 8: 140–148. © 2014 American Association of Anatomists.
Highly Efficient Orange and Warm White Phosphorescent OLEDs Based on a Host Material with a Carbazole–Fluorenyl Hybrid
Authors: Du Xiaoyang , Huang Yun , Tao Silu , Yang Xiaoxia , Wu Chuan , Wei Huaixin , Chan Mei‐Yee , Yam Vivian Wing‐Wah , Lee Chun‐Sing
Published: April 2014

A new carbazole–fluorenyl hybrid compound, 3,3′(2,7‐di(naphthaline‐2‐yl)‐9H‐fluorene‐9,9‐diyl)bis(9‐phenyl‐9H‐carbazole) (NFBC) was synthesized and characterized. The compound exhibits blue‐violet emission both in solution and in film, with peaks centered at 404 and 420 nm. In addition to the application as a blue emitter, NFBC is demonstrated to be a good host for phosphorescent dopants. By doping Ir(2‐phq)3 in NFBC, a highly efficient orange organic light‐emitting diode (OLED) with a maximum efficiency of 32 cd A−1 (26.5 Lm W−1) was obtained. Unlike most phosphorescent OLEDs, the device prepared in our study shows little efficiency roll‐off at high brightness and maintains current efficiencies of 31.9 and 26.8 cd A−1 at a luminance of 1000 and 10 000 cd m−2, respectively. By using NFBC simultaneously as a blue fluorescence emitter and as a host for a phosphorescent dopant, a warm white OLED with a maximum efficiency of 22.9 Lm W−1 (21.9 cd A−1) was also obtained.
A Reversible Dual Mode Chemodosimeter for the Detection of Cyanide Ions in Natural Sources
Authors: Shankar Balaraman H. , Jayaram Dhanya T. , Ramaiah Danaboyina
Published: April 2014

Herein, we report the synthesis of two indolium probes 1 and 2 based on anthracene and pyrene derivatives and their interactions with various anions. Of these probes, the pyrene conjugate 2 acts as a dual colorimetric and fluorescent chemodosimeter for the selective and sensitive detection of cyanide ions. The detection limit of probe 2 for CN− ions was found to be 10 ppb (30 nM). The nature of interaction has been thoroughly studied through various techniques such as 1H NMR and IR spectroscopy, HRMS, and isothermal calorimetric (ITC) studies. These studies confirm that probe 2 forms a 1,2‐adduct in the presence of CN− ions. Kinetic studies using probe 2 showed the completion of the reaction within 15 s with a rate constant of k′=0.522±0.063 s−1. This probe can be coated on a solid surface (dipstick) and a polymer matrix for the on‐site analysis and quantification of endogenous cyanide ions in natural sources such as Indian almonds.
Pluviometric ID: precipitation characteristics at a glance
Authors: de Pessôa João Augusto
Published: April 2014

This article proposes the Pluviometric ID, a graphic representation of the main precipitation characteristics from a given dataset. The Pluviometric ID exceeds the traditional depiction of rainfall data as it allows a fast and simultaneous perception of parameters such as seasonal and interannual precipitation pattern changes, historic data series (length and integrity), cumulative and distributed (daily) long‐term mean precipitation, among others. When plotted on a web map, the Precipitation ID quickly projects the regional precipitation patterns and trends towards a particular visually chosen direction. Non‐standard patterns may eventually arise and be easily spotted.
Intact Facial Adaptation in Autistic Adults
Authors: Cook Richard , Brewer Rebecca , Shah Punit , Bird Geoffrey
Published: April 2014

Adaptation paradigms seek to bias subsequently viewed stimuli through prolonged exposure to an adapting stimulus, thereby giving rise to an aftereffect. Recent experiments have found that children with autism spectrum disorders (ASD) show reduced facial aftereffects, prompting some researchers to speculate that all individuals with ASD exhibit deficient facial adaptation. However, caution is required when generalizing findings from samples of children with ASD to the wider ASD population. The reduced facial aftereffects seen in child samples may instead reflect delayed or atypical developmental trajectories, whereby individuals with ASD are slower to develop adaptive mechanisms. In the present study, two experiments were conducted to determine whether high‐functioning adults with ASD also show diminished aftereffects for facial identity and expression. In Experiment 1, using a procedure that minimized the contribution of low‐level retinotopic adaptation, we observed substantial aftereffects comparable to those seen in matched controls, for both facial identity and expression. A similar pattern of results was seen in Experiment 2 using a revised procedure that increased the contribution of retinotopic adaptation to the facial aftereffects observed. That adults with autism can show robust facial aftereffects raises the possibility that group differences are seen only at particular points during development, and may not be a lifelong feature of the condition. Autism Res 2014, 7: 481–490. © 2014 International Society for Autism Research, Wiley Periodicals, Inc.
Maximum type 1 error rate inflation in multiarmed clinical trials with adaptive interim sample size modifications
Authors: Graf Alexandra C. , Bauer Peter , Glimm Ekkehard , Koenig Franz
Published: April 2014

Sample size modifications in the interim analyses of an adaptive design can inflate the type 1 error rate, if test statistics and critical boundaries are used in the final analysis as if no modification had been made. While this is already true for designs with an overall change of the sample size in a balanced treatment‐control comparison, the inflation can be much larger if in addition a modification of allocation ratios is allowed as well. In this paper, we investigate adaptive designs with several treatment arms compared to a single common control group. Regarding modifications, we consider treatment arm selection as well as modifications of overall sample size and allocation ratios. The inflation is quantified for two approaches: a naive procedure that ignores not only all modifications, but also the multiplicity issue arising from the many‐to‐one comparison, and a Dunnett procedure that ignores modifications, but adjusts for the initially started multiple treatments. The maximum inflation of the type 1 error rate for such types of design can be calculated by searching for the “worst case” scenarios, that are sample size adaptation rules in the interim analysis that lead to the largest conditional type 1 error rate in any point of the sample space. To show the most extreme inflation, we initially assume unconstrained second stage sample size modifications leading to a large inflation of the type 1 error rate. Furthermore, we investigate the inflation when putting constraints on the second stage sample sizes. It turns out that, for example fixing the sample size of the control group, leads to designs controlling the type 1 error rate.
Minimizing fucosylation in insect cell‐derived glycoproteins reduces binding to IgE antibodies from the sera of patients with allergy
Authors: Palmberger Dieter , Ashjaei Kazem , Strell Stephanie , Hoffmann‐Sommergruber Karin , Grabherr Reingard
Published: April 2014

The baculovirus/insect cell system has proven to be a very powerful tool for the expression of several therapeutics. Nevertheless, these products sometimes suffer from reduced biological activity and unwanted side effects. Several studies have demonstrated that glycosylation can greatly influence the structure, function, half‐life, antigenicity and immunogenicity of various glycoproteins. Yet, the glycosylation pattern of insect cell‐derived products is not favorable for many applications. Especially, the presence of core α1,3‐linked fucose bears the risk of causing immediate hypersensitivity reactions in patients with allergy. In this study, we evaluated the impact of fucose residues on the allergenic potential of an insect cell‐expressed vaccine candidate. In order to block the GDP‐L‐fucose de novo synthesis pathway, we integrated the Pseudomonas aeruginosa GDP‐6‐deoxy‐D‐lyxo‐4‐hexulose reductase (RMD) gene into a baculovirus backbone. This virus was then used for the expression of soluble influenza A virus hemagglutinin (HA). Expression studies showed that the co‐expression of RMD did not influence the overall level of recombinant protein secretion. We confirmed the result of our strategy by analyzing PNGase A‐released N‐glycans using MALDI‐TOF‐MS. In order to evaluate the biological impact of defucosylation of influenza HA we tested the binding activity of IgE derived from the sera of patients with allergy to the purified antigen. The non‐fucosylated HA showed a 10‐fold decrease in IgE binding levels as compared to wildtype variants.

same article under 10.1002/biot.201300061.
Early sac shrinkage predicts a low risk of late complications after endovascular aortic aneurysm repair
Authors: Bastos Gonçalves F , Baderkhan H , Verhagen H J M , Wanhainen A , Björck M , Stolker R J , Hoeks S E , Mani K
Published: April 2014

Background

Aneurysm shrinkage has been proposed as a marker of successful endovascular aneurysm repair (EVAR). Patients with early postoperative shrinkage may experience fewer subsequent complications, and consequently require less intensive surveillance.

Methods

Patients undergoing EVAR from 2000 to 2011 at three vascular centres (in 2 countries), who had two imaging examinations (postoperative and after 6–18 months), were included. Maximum diameter, complications and secondary interventions during follow-up were registered. Patients were categorized according to early sac dynamics. The primary endpoint was freedom from late complications. Secondary endpoints were freedom from secondary intervention, postimplant rupture and direct (type I/III) endoleaks.

Results

Some 597 EVARs (71·1 per cent of all EVARs) were included. No shrinkage was observed in 284 patients (47·6 per cent), moderate shrinkage (5–9 mm) in 142 (23·8 per cent) and major shrinkage (at least 10 mm) in 171 patients (28·6 per cent). Four years after the index imaging, the rate of freedom from complications was 84·3 (95 per cent confidence interval 78·7 to 89·8), 88·1 (80·6 to 95·5) and 94·4 (90·1 to 98·7) per cent respectively. No shrinkage was an independent risk factor for late complications compared with major shrinkage (hazard ratio (HR) 3·11; P < 0·001). Moderate compared with major shrinkage (HR 2·10; P = 0·022), early postoperative complications (HR 3·34; P < 0·001) and increasing abdominal aortic aneurysm baseline diameter (HR 1·02; P = 0·001) were also risk factors for late complications. Freedom from secondary interventions and direct endoleaks was greater for patients with major sac shrinkage.

Conclusion

Early change in aneurysm sac diameter is a strong predictor of late complications after EVAR. Patients with major sac shrinkage have a very low risk of complications for up to 5 years. This parameter may be used to tailor postoperative surveillance.
The influence of COMT Val158Met genotype on the character dimension cooperativeness in healthy females
Authors: Baeken Chris , Claes Stephan , De Raedt Rudi
Published: April 2014

Objectives

Although the Val158Met catechol‐O‐methyltransferase (COMT) gene has been linked with the temperament dimension Novelty Seeking (NS), new insights in this polymorphism might point to a major role for character features as well. Given that individual life experiences may influence Val158 and Met158 allele carriers differently it has been suggested that the character trait cooperativeness could be implicated.

Case report

A homogeneous group of eighty right‐handed Caucasian healthy female university students were assessed with the TCI and genotyped for the COMT Val158Met polymorphism (rs4680). Gene determination showed that eighteen were Val158 homozygotes, forty‐four Val/Met158 heterozygotes, and eighteen were Met158 homozygotes. All were within the same age range and never documented to have suffered from any neuropsychiatric illness. Bonferroni corrected non‐parametric analyses showed that only for the character scale cooperativeness Val158 homozygotes displayed significant higher scores when compared to Met158 homozygotes. No significant differences on cooperativeness scores were found between Val158 and Val/Met158 carriers or between Met158 and Val/Met158 carriers. No differences were observed for the COMT Val158Met polymorphism and the other temperament and character scales.

Conclusions

Our findings support the assumption that the Val158Met single nucleotide polymorphism (SNP) influences character traits and not only temperament. Our results add to the notion that Val158 homozygotes are considered to be helpful and empathic and it suggest that these cooperativeness character traits are related to the dopaminergic system.
Perfluorobutyric Acid and Its Monohydrate: A Chirped Pulse and Cavity Based Fourier Transform Microwave Spectroscopic Study
Authors: Thomas Javix , Serrato Agapito , Lin Wei , Jäger Wolfgang , Xu Yunjie
Published: April 2014

Rotational spectra of perfluorobutyric acid (PFBA) and its monohydrate were studied with a broadband chirped pulse and a narrow‐band cavity based Fourier transform microwave spectrometer, and high‐level ab initio calculations. Extensive conformational searches were performed for both the acid and its monohydrate at the MP2/6‐311++G(2d,p) level of theory. Two and three conformers were predicted to exist for PFBA and its monohydrate, respectively. One set of rotational transitions was observed and assigned for each, PFBA and its monohydrate. Based on the measured broadband spectra, we confidently conclude that only one dominant conformer exists in each case. The orientation of the hydroxyl group in PFBA was determined by using isotopic analysis. Comparison of the observed transition intensities and the calculated electric dipole moment components allowed us to identify the most stable monohydrate conformation, which takes on an insertion hydrogen‐bonding topology. Comparisons to the shorter chain analogues, that is, trifluoroacetic acid, perfluoropropionic acid, and their monohydrates, are made to elucidate the general trend in their conformational preference and binding topologies.
Combinatorial Approach to Chiral Tris‐ligated Carbophilic Platinum Complexes: Application to Asymmetric Catalysis
Authors: Pradal Alexandre , Gladiali Serafino , Michelet Veronique , Toullec Patrick Y.
Published: April 2014

A straightforward methodology for the synthesis of libraries of chiral tris‐ligated cationic platinum complexes and their in situ evaluation as asymmetric carbophilic catalysts in a model domino hydroarylation/cyclization reaction of a 1,6‐enyne was developed. A catalyst‐generation process based on a combination of a monodentate and a bidentate phosphorus ligand allowed the formation of 108 chiral complexes. One‐pot screening of the stereoinduction obtained with this library in a test domino addition/cyclization reaction validated this approach and stressed the key role played by the monodentate ligand partner in obtaining high enantioselectivities. In the case of two challenging substrate/nucleophile combinations, the combinatorial approach resulted in a significant gain in enantioselectivity.
Copper‐Catalyzed Dehydrogenative Cross‐Coupling Reaction between Allylic CH Bonds and α‐CH Bonds of Ketones or Aldehydes
Authors: Huang Xing‐Fen , Salman Muhammad , Huang Zhi‐Zhen
Published: April 2014

A dehydrogenative cross‐coupling reaction between allylic CH bonds and the α‐CH bond of ketones or aldehydes was developed using Cu(OTf)2 as a catalyst and DDQ as an oxidant. This synthetic approach to γ,δ‐unsaturated ketones and aldehydes has the advantages of broad scope for both ketones and aldehydes as reactants, mild reaction conditions, good yields and atom economy. A plausible mechanism using Cu(OTf)2 as a Lewis acid catalyst was also proposed (DDQ=2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone; Tf=trifluoromethanesulfonate).
Multivalent Recognition of Concanavalin A by {Mo132} Glyconanocapsules—Toward Biomimetic Hybrid Multilayers
Authors: Barboiu Mihail , Mouline Zineb , Silion Mihaela , Licsandru Erol , Simionescu Bogdan C. , Mahon Eugene , Pinteala Mariana
Published: April 2014

Herein, we consider Müller’s spherical, porous, anionic, molybdenum oxide based capsule, (NH4)42‐ [{(MoVI)MoVI5O21(H2O)6}12{MoV2O4(CH3COO)}30]⋅10 CH3COONH4⋅ 300 H2O≡(NH4)42⋅1 a⋅crystal ingredients≡1, {Mo132}, as an effective sugar‐decorated nanoplatform for multivalent lectin recognition. The ion‐exchange of NH4+ ions of 1 with cationic‐sugars, D‐mannose‐ammonium chloride (2) or D‐glucose‐ammonium chloride (3) results in the formation of glyconanocapsules (NH4)42−n2n⋅1 a and (NH4)42−m3m⋅1 a. The Mannose (NH4)42−n2n⋅1 a capsules bind selectively Concanavalin A (Con A) in aqueous solution, giving an association avidity constant of ${K{{{\rm multi}\hfill \atop {\rm a}\hfill}}}$=4.6×104 M−1 and an enhancement factor of β=K${{{{\rm multi}\hfill \atop {\rm a}\hfill}}}$/K${{{{\rm mono}\hfill \atop {\rm ass}\hfill}}}$=21.9, reminiscent of the formation of “glycoside clusters” on the external surface of glyconanocapsule. The glyconanocapsules (NH4)42−n2n⋅1 a and (NH4)42−m3m⋅1 a self‐assemble in “hybrid multilayers” by successive layer‐by‐layer deposition of (NH4)42−n2n⋅1 a or (NH4)42−m3m⋅1 a and Con A. These architectures, reminiscent of versatile mimics of artificial tissues, can be easily prepared and quantified by using quartz crystal microgravimetry (QCM). The “biomimetic hybrid multilayers” described here are stable under a continual water flow and they may serve as artificial networks for a greater depth of understanding of various biological mechanisms, which can directly benefit the fields of chemical separations, sensors or storage‐delivery devices.
Activation of Elemental Sulfur by Aluminum Dihydride: Isolation of Mono‐ and Bis(hydrogensulfide) Complexes of Aluminum
Authors: Franz Daniel , Inoue Shigeyoshi
Published: April 2014

The conversions of the dimeric imidazolin‐2‐iminato aluminum dihydride {μ‐LDippAlH2}2 (1) with 1/4 or 1/2 equivalents of S8 gave the elusive hydrogensulfide {μ‐LDippAl(H)SH}2 (2) and the bisthiol {μ‐LDippAl(SH)2}2 (3), respectively (LDipp=NC(N(Dipp)CH)2, Dipp=2,6‐diisopropylphenyl). Notably, these transformations proceeded in the absence of a promoter. The reaction of {μ‐LMesAlH2}2 (4), a less bulky congener of 1, with phenyl disulfide produces the phenyl sulfide {μ‐LMesAl(H)SPh}2 (5; LMes=NC(N(Mes)CH)2, Mes=2,4,6‐trimethylphenyl). The hitherto unknown compounds 2–5 were characterized by using spectroscopic methods and single‐crystal X‐ray diffraction analysis.
Hyperbranched Supramolecular Polymer of Tris(permethyl‐β‐cyclodextrin)s with Porphyrins: Characterization and Magnetic Resonance Imaging
Authors: Sun Mo , Zhang Hengyi , Hu Xinyue , Liu Bowen , Liu Yu
Published: April 2014

A hyperbranched supramolecular polymer (HSP) is constructed based on the intermolecular inclusion complexation of bridged tris(permethyl‐β‐cyclodextrin) with MnIII‐porphyrin bearing poly(ethylene glycol) (PEG) side chains (MnIII‐TPP), and characterized by UV/vis absorption spectroscopy, isothermal titration calorimetry (ITC), NMR, dynamic light scattering (DLS), atomic force microscopy (AFM) and transmission electron microscopy (TEM), respectively. The presence of permethyl‐β‐cyclodextrin can stabilize the low‐valent MnII‐TPP. In vitro cell experiment indicates that this HSP has no remarkable cellular toxicity against NIH 3T3 cells. In vitro MR imaging experiment indicates a slightly increased T1 relaxivity for this HSP compared to that for the linear supramolecular polymer.
Glycolaldehyde and maleyl conjugated human serum albumin as potential macrophage‐targeting carriers for molecular imaging purposes
Authors: Gustafsson Björn , Hedin Ulf , Caidahl Kenneth
Published: April 2014

Maleylated bovine serum albumin is a known ligand for targeting macrophages and has potential as a carrier for molecular imaging purposes. We present a novel synthesis of glycolaldehyde‐conjugated human serum albumin (GA‐HSA) and maleylated human serum albumin (Mal‐HSA). Seventeen modifications of fluorescently tagged GA‐HSA and Mal‐HSA molecules with different degrees of conjugation were prepared. The comparative uptake studies, using 12 of these modifications, were done in vitro on mouse monocytes/macrophages (RAW264.7), and evaluated qualitatively by confocal microscopy and quantitatively by flow cytometry. The GA modifications are taken up by the macrophages approximately 40% better than the maleyl modifications at low concentrations (≤3 μm), while at higher concentrations it appears that the maleyl modifications are taken up around 25–44% better than the GA‐modified HSA. However, high uptake at low concentrations will be beneficial for in vivo localizing inflammation in areas with low penetration of the probe as in an atherosclerotic plaque. Further, another advantage of GA‐HSA is that GA competes less than the maleyl group for the free reactive amine sites that are to be used for conjugation of metal chelating ligands (e.g. tetraazacyclododecanetetraacetic acid and triazacyclononanetriacetic acid). Metal ions such as Gd3+ and Mn2+ can be chelated for positive Magnetic Resonance (MR) contrast and positron emitting ions such as 64Cu2+ and 68Ga3+ for Positron Emission Tomography (PET) imaging. These are important properties, especially, when considering the MR contrast possibilities owing to the low sensitivity of the technique, and would motivate the use of GA‐HSA before Mal‐HSA. © 2014 The Authors. Contrast Media & Molecular Imaging published by John Wiley & Sons, Ltd.
Microporous Carbon and Mesoporous Silica by Use of Twin Polymerization: An Integrated Experimental and Theoretical Approach to Precursor Reactivity
Authors: Kitschke Philipp , Auer Alexander A. , Löschner Tina , Seifert Andreas , Spange Stefan , Rüffer Tobias , Lang Heinrich , Mehring Michael
Published: April 2014

Spirocyclic silicon alkoxides were synthesized by reaction of Si(OMe)4 with derivatives of salicylic alcohol and studied by in situ differential scanning calorimetry with regard to twin polymerization (TP). Both, thermally induced and proton‐assisted TP gave nanostructured hybrid materials composed of a phenolic resin and silica. Carbonization and subsequent treatment with HF(aq) resulted in microporous carbon, whereas oxidation in air provided mesoporous silica. DFT calculations were performed to obtain a more detailed insight into the first reaction steps of proton‐assisted TP and to support the hypothesis of a reactivity scale based on steric and electronic features of the silicon‐containing precursors (twin monomers). The calculated reaction barriers for the initial reaction steps of proton‐assisted TP are qualitatively in accordance with the Hammett constants of the substituents at the salicylate moiety. This result offers a simple method to predict the reactivity for twin monomers.
Synthesis of bamboo‐like SiC whiskers from waste silica fume
Authors: Li Qingcui , Wang Chang‐An , Tie Shengnian
Published: April 2014

A process for the utilization of wasted silica fume is proposed in this work. Silicon carbide (SiC) whiskers several tens of micrometers in length and with a bamboo‐like morphology have been successfully synthesized by a carbothermal reduction process using purified silica fume as the silicon source. The morphology and structure of SiC whiskers were investigated by X‐ray diffraction, Raman spectroscopy, scanning electron microscopy, and high‐resolution transmission electron microscopy. Studies found that the as‐synthesized whiskers were grown as single‐crystalline β‐SiC along the (111) growth direction. The whiskers consisted of hexagonal stems randomly decorated with larger‐diameter knots along their whole length. On the basis of the characterization results, a vapor–solid process was discussed as a possible growth mechanism of the β‐SiC whiskers.
Combination of Carbon Nitride and Carbon Nanotubes: Synergistic Catalysts for Energy Conversion
Authors: Gong Yutong , Wang Jing , Wei Zhongzhe , Zhang Pengfei , Li Haoran , Wang Yong
Published: April 2014

Due to their versatile features and environmental friendliness, functionalized carbon materials show great potential in practical applications, especially in energy conversion. Developing carbon composites with properties that can be modulated by simply changing the ratio of the original materials is an intriguing synthetic strategy. Here, we took cyanamide and multiwalled carbon nanotubes as precursors and introduced a facile method to fabricate a series of graphitic carbon nitride/carbon nanotubes (g‐C3N4/CNTs) composites. These composites demonstrated different practical applications with different weight ratios of the components, that is, they showed synergistic effects in optoelectronic conversion when g‐C3N4 was the main ingredient and in oxygen reduction reaction (ORR) when CNTs dominated the composites. Our experiments indicated that the high electrical conductivity of carbon nanotubes promoted the transmission of the charges in both cases.
Neurotransmitter map of the asymmetric dorsal habenular nuclei of zebrafish
Authors: deCarvalho Tagide N. , Subedi Abhignya , Rock Jason , Harfe Brian D. , Thisse Christine , Thisse Bernard , Halpern Marnie E. , Hong Elim
Published: April 2014

The role of the habenular nuclei in modulating fear and reward pathways has sparked a renewed interest in this conserved forebrain region. The bilaterally paired habenular nuclei, each consisting of a medial/dorsal and lateral/ventral nucleus, can be further divided into discrete subdomains whose neuronal populations, precise connectivity, and specific functions are not well understood. An added complexity is that the left and right habenulae show pronounced morphological differences in many non‐mammalian species. Notably, the dorsal habenulae of larval zebrafish provide a vertebrate genetic model to probe the development and functional significance of brain asymmetry. Previous reports have described a number of genes that are expressed in the zebrafish habenulae, either in bilaterally symmetric patterns or more extensively on one side of the brain than the other. The goal of our study was to generate a comprehensive map of the zebrafish dorsal habenular nuclei, by delineating the relationship between gene expression domains, comparing the extent of left–right asymmetry at larval and adult stages, and identifying potentially functional subnuclear regions as defined by neurotransmitter phenotype. Although many aspects of habenular organization appear conserved with rodents, the zebrafish habenulae also possess unique properties that may underlie lateralization of their functions. genesis 52:636–655, 2014. © 2014 Wiley Periodicals, Inc.
Left–right asymmetry of the gnathostome skull: Its evolutionary, developmental, and functional aspects
Authors: Compagnucci Claudia , Fish Jennifer , Depew Michael J.
Published: April 2014

Much of the gnathostome (jawed vertebrate) evolutionary radiation was dependent on the ability to sense and interpret the environment and subsequently act upon this information through utilization of a specialized mode of feeding involving the jaws. While the gnathostome skull, reflective of the vertebrate baüplan, typically is bilaterally symmetric with right (dextral) and left (sinistral) halves essentially representing mirror images along the midline, both adaptive and abnormal asymmetries have appeared. Herein we provide a basic primer on studies of the asymmetric development of the gnathostome skull, touching briefly on asymmetry as a field of study, then describing the nature of cranial development and finally underscoring evolutionary and functional aspects of left–right asymmetric cephalic development. genesis 52:515–527, 2014. © 2014 Wiley Periodicals, Inc.
Influence of whitebark pine decline on fall habitat use and movements of grizzly bears in the Greater Yellowstone Ecosystem
Authors: Costello Cecily M. , van Manen Frank T. , Haroldson Mark A. , Ebinger Michael R. , Cain Steven L. , Gunther Kerry A. , Bjornlie Daniel D.
Published: April 2014

When abundant, seeds of the high‐elevation whitebark pine (WBP;Pinus albicaulis) are an important fall food for grizzly bears (Ursus arctos) in the Greater Yellowstone Ecosystem. Rates of bear mortality and bear/human conflicts have been inversely associated withWBPproductivity. Recently, mountain pine beetles (Dendroctonus ponderosae) have killed many cone‐producingWBPtrees. We used fall (15 August–30 September) Global Positioning System locations from 89 bear years to investigate temporal changes in habitat use and movements during 2000–2011. We calculated Manly–Chesson (MC) indices for selectivity ofWBPhabitat and secure habitat (≥500 m from roads and human developments), determined dates ofWBPuse, and documented net daily movement distances and activity radii. To evaluate temporal trends, we used regression, model selection, and candidate model sets consisting of annualWBPproduction, sex, and year. One‐third of sampled grizzly bears had fall ranges with little or no mappedWBPhabitat. Most other bears (72%) had aMCindex above 0.5, indicating selection forWBPhabitats. From 2000 to 2011, meanMCindex decreased and median date ofWBPuse shifted about 1 week later. We detected no trends in movement indices over time. Outside of national parks, there was no correlation between theMCindices forWBPhabitat and secure habitat, and most bears (78%) selected for secure habitat. Nonetheless, meanMCindex for secure habitat decreased over the study period during years of goodWBPproductivity. The wide diet breadth and foraging plasticity of grizzly bears likely allowed them to adjust to decliningWBP. Bears reduced use ofWBPstands without increasing movement rates, suggesting they obtained alternative fall foods within their local surroundings. However, the reduction in mortality risk historically associated with use of secure, high‐elevationWBPhabitat may be diminishing for bears residing in multiple‐use areas.
Asymmetric Diastereoselective Synthesis of Spirocyclopropane Derivatives of Oxindole
Authors: Ošeka Maksim , Noole Artur , Žari Sergei , Öeren Mario , Järving Ivar , Lopp Margus , Kanger Tõnis
Published: April 2014

A new asymmetric organocatalytic synthesis of spirocyclopropane oxindoles has been developed. The method is based on the Michael addition of N‐Boc‐protected 3‐chlorooxindole to unsaturated 1,4‐dicarbonyl compounds, affording trans‐substituted spirocyclopropane oxindole derivatives in high diastereo‐ and enantioselectivity.
Spectrum trading algorithm based on memory in cognitive radio network
Authors: Zhang Shibing , Zhang Guodong , Bao Zhihua , Zhang Xiaoge
Published: April 2014

In cognitive radio networks, the most important goal of spectrum sharing is to benefit both the seller and buyer. In order to increase the total benefits generated in spectrum sharing, this paper introduces a memory mechanism between the spectrum agent and multi‐primary service providers (PSPs) and proposes a spectrum trading algorithm based on the mechanism. In this algorithm, all PSPs compete with each other and sell their idle spectrum resource to the agent to maximise their own profits. Then, the agent auctions the spectrum resources obtained in multi‐secondary users. Finally, a new auction pricing function is designed to decrease the auction trading prices and increase the benefits of secondary users. Nash equilibrium is considered to be the optimal result. Simulation results show that the proposed algorithm provides 10–15% margin over the conventional algorithm both in the price and spectrum quantity. Copyright © 2014 John Wiley & Sons, Ltd.
Interference management in LTE‐based HetNets: a practical approach
Authors: Font‐Bach O. , Bartzoudis N. , Pascual‐Iserte A. , Payaró M. , Blanco L. , López Bueno D. , Molina M.
Published: April 2014

Interference is a major obstacle in radio communications, especially when opportunistic frequency reuse is an inherent requirement for maximising spectral efficiency in heterogeneous networks. A typical example is encountered in cellular communications where macrocell‐edge users receive interference from small cell transmissions that use the same radio frequency band. Innovating interference management algorithms are employed towards this end, which because of their interdependencies with numerous parameters of the target operating scenario and various low‐level implementation aspects, need to be prototyped in real‐time signal processing platforms in order to be credibly verified. In this paper, we present the development and experimental validation of a macrocell/femtocell coexistence scenario in close to real‐life conditions. The inclusion of an agile interference management scheme increased the signal processing complexity at the physical layer. This overhead was appropriately addressed by engaging advanced parallel processing techniques, optimisations of the arithmetic operations and intelligent reuse of logic and memory resources in the field programmable gate array (FPGA)‐based baseband processing architecture. Copyright © 2014 John Wiley & Sons, Ltd.
Causes and Implications of Shifts in Financial Participation in Commodity Markets
Authors: Fattouh Bassam , Mahadeva Lavan
Published: April 2014

We assess the causes and implications of the greater financial participation in commodity markets post‐2003. Focusing on crude oil, we build a calibrated macro‐finance model of oil prices and quantities that also determines consumer welfare. We show that shifts in the preferences and constraints of financial speculators cannot explain the observed movement in the futures spread and so are unlikely to expose consumer welfare to shocks, even in the presence of belief disagreements. Shifts in the supply and demand for spot oil can better explain many of the features often attributed to financialization including financial participation itself. © 2014 Wiley Periodicals, Inc. Jrl Fut Mark 34:757–787, 2014
Hoarding the Herd: The Convenience of Productive Stocks
Authors: Asche Frank , Oglend Atle , Zhang Dengjun
Published: April 2014

This paper investigates the convenience yield that emerges in markets with productive stocks. We isolate the economic fundamentals giving rise to the yield, and show how these map to the empirical convenience yield measure. A model for price dynamics is derived from an economic model for optimal stock levels. We show how the price process reduces to a simple non‐linear first‐order Markov process. The model is estimated for the Norwegian market for farmed salmon by Generalized Methods of Moments, where stock growth is approximated by sea‐water temperature. Our estimation result supports the theorized role of stock growth as a convenience yield component. Our results are relevant for the functioning of futures markets for commodities such as fish and other animal production where systematic stock growth affects the term structure. © 2014 Wiley Periodicals, Inc. Jrl Fut Mark 35:679–694, 2015
A historical surface climate dataset from station observations in Mediterranean North Africa and Middle East areas
Authors: Brunet Manola , Gilabert Alba , Jones Phil , Efthymiadis Dimitrios
Published: April 2014

Historical climatic data from station observations taken in North African and Middle East Mediterranean countries since the second half of the 19th century have been digitized and quality‐controlled in the framework of the EU‐funded European Reanalysis and Observations for Monitoring (EURO4M) project. Daily maximum and minimum temperatures and precipitation totals, along with sub‐daily data for surface air pressure have been recovered by using historical data sources involving book/logbook collections archived in national and international data centres. The new dataset produced comprises climatic time series for 79 stations that have operated in southern and eastern Mediterranean countries. While the developed time series have data gaps, every effort has been made to infill these gaps, to improve assessments of the long‐term changes in climate variability in the region.
Large Cross‐Free Sets in Steiner Triple Systems
Authors: Gyárfás András
Published: April 2014

Across‐freeset of sizemin a Steiner triple systemis three pairwise disjointm‐element subsetssuch that nointersects all the three‐s. We conjecture that for every admissiblenthere is an STS(n) with a cross‐free set of sizewhich if true, is best possible. We prove this conjecture for the case, constructing an STScontaining a cross‐free set of size 6k. We note that some of the 3‐bichromatic STSs, constructed by Colbourn, Dinitz, and Rosa, have cross‐free sets of size close to 6k(but cannot have size exactly 6k). The constructed STSshows that equality is possible forin the following result: in every 3‐coloring of the blocks of any Steiner triple system STS(n) there is a monochromatic connected component of size at least(we conjecture that equality holds for every admissiblen). The analog problem can be asked forr‐colorings as well, ifandis a prime power, we show that the answer is the same as in case of complete graphs: in everyr‐coloring of the blocks of any STS(n), there is a monochromatic connected component with at leastpoints, and this is sharp for infinitely manyn.