bluuebunny/crossref_metadata_2025 huggingface dataset:
Crystal Structure of Tryptophan Lyase (NosL): Evidence for Radical Formation at the Amino Group of Tryptophan
Authors: Nicolet Yvain , Zeppieri Laura , Amara Patricia , Fontecilla‐Camps Juan C.
Published: September 2014

Streptomyces actuosus tryptophan lyase (NosL) is a radical SAM enzyme which catalyzes the synthesis of 3‐methyl‐2‐indolic acid, a precursor in the synthesis of the promising antibiotic nosiheptide. The reaction involves cleavage of the tryptophan CαCβ bond and recombination of the amino‐acid‐derived ‐COOH fragment at the indole ring. Reported herein is the 1.8 Å resolution crystal structure of NosL complexed with its substrate. Unexpectedly, only one of the tryptophan amino hydrogen atoms is optimally placed for H abstraction by the SAM‐derived 5′‐deoxyadenosyl radical. This orientation, in turn, rules out the previously proposed delocalized indole radical as the species which undergoes CαCβ bond cleavage. Instead, stereochemical considerations indicate that the reactive intermediate is a .NH tryptophanyl radical. A structure‐based amino acid sequence comparison of NosL with the tyrosine lyases ThiH and HydG strongly suggests that an equivalent .NH radical operates in the latter enzymes.
Anti‐Electrostatic Hydrogen Bonds
Authors: Weinhold Frank , Klein Roger A.
Published: September 2014

Ab initio and hybrid density functional techniques were employed to characterize a surprising new class of H‐bonded complexes between ions of like charge. Representative H‐bonded complexes of both anion–anion and cation–cation type exhibit appreciable kinetic stability and the characteristic theoretical, structural, and spectroscopic signatures of hydrogen bonding, despite the powerful opposition of Coulomb electrostatic forces. All such “anti‐electrostatic” H‐bond (AEHB) species confirm the dominance of resonance‐type covalency (“charge transfer”) interactions over the inessential (secondary or opposing) “ionic” or “dipole–dipole” forces that are often presumed to be essential for numerical modeling or conceptual explanation of the H‐bonding phenomenon.
Synthetic Molecules that Protect Cells from Anoikis and Their Use in Cell Transplantation
Authors: Frisco‐Cabanos Heidie L. , Watanabe Mizuki , Okumura Naoki , Kusamori Kosuke , Takemoto Naohiro , Takaya Junichiro , Sato Shin‐ichi , Yamazoe Sayumi , Takakura Yoshinobu , Kinoshita Shigeru , Nishikawa Makiya , Koizumi Noriko , Uesugi Motonari
Published: September 2014

One of the major problems encountered in cell transplantation is the low level of survival of transplanted cells due to detachment‐induced apoptosis, called anoikis. The present study reports on the chemical synthesis and biological evaluation of water‐soluble molecules that protect suspended cells from anoikis. The synthetic molecules bind to and induce clusters of integrins and heparan‐sulfate‐bound syndecans, two classes of receptors that are important for extracellular matrix‐mediated cell survival. Molecular biological analysis indicates that such molecules prolong the survival of suspended NIH3T3 cells, at least in part, by promoting clustering of syndecan‐4 and integrin β1 on the cell surface, leading to the activation of small GTPase Rac‐1 and Akt. In vivo experiments using animal disease models demonstrated the ability of the molecules to improve cell engraftment. The cluster‐inducing molecules may provide a starting point for the design of new synthetic tools for cell‐based therapy.
Exploration of Conformational Spaces of High‐Mannose‐Type Oligosaccharides by an NMR‐Validated Simulation
Authors: Yamaguchi Takumi , Sakae Yoshitake , Zhang Ying , Yamamoto Sayoko , Okamoto Yuko , Kato Koichi
Published: September 2014

Exploration of the conformational spaces of flexible biomacromolecules is essential for quantitatively understanding the energetics of their molecular recognition processes. We employed stable isotope‐ and lanthanide‐assisted NMR approaches in conjunction with replica‐exchange molecular dynamics (REMD) simulations to obtain atomic descriptions of the conformational dynamics of high‐mannose‐type oligosaccharides, which harbor intracellular glycoprotein‐fate determinants in their triantennary structures. The experimentally validated REMD simulation provided quantitative views of the dynamic conformational ensembles of the complicated, branched oligosaccharides, and indicated significant expansion of the conformational space upon removal of a terminal mannose residue during the functional glycan‐processing pathway.
Electron‐Transfer Photochromism To Switch Bulk Second‐Order Nonlinear Optical Properties with High Contrast
Authors: Li Pei‐Xin , Wang Ming‐Sheng , Zhang Ming‐Jian , Lin Chen‐Sheng , Cai Li‐Zhen , Guo Sheng‐Ping , Guo Guo‐Cong
Published: September 2014

The first bulk electron‐transfer photochromic compound with intrinsic second‐order nonlinear optical (NLO) photoswitching properties has been synthesized. This system employs an electron‐transfer photoactive asymmetric viologen ligand coordinated to a zinc(II) center.
Gas‐Phase Preparation of Carbonic Acid and Its Monomethyl Ester
Authors: Reisenauer Hans Peter , Wagner J. Philipp , Schreiner Peter R.
Published: September 2014

Carbonic acid (H2CO3), an essential molecule of life (e.g., as bicarbonate buffer), has been well characterized in solution and in the solid state, but for a long time, it has eluded its spectral characterization in the gas phase owing to a lack of convenient preparation methods; microwave spectra were recorded only recently. Here we present a novel and general method for the preparation of H2CO3 and its monomethyl ester (CH3OCO2H) through the gas‐phase pyrolysis of di‐tert‐butyl and tert‐butyl methyl carbonate, respectively. H2CO3 and CH3OCO2H were trapped in noble‐gas matrices at 8 K, and their infrared spectra match those computed at high levels of theory [focal point analysis beyond CCSD(T)/cc‐pVQZ] very well. Whereas the spectra also perfectly agree with those of the vapor phase above the β‐polymorph of H2CO3, this is not true for the previously reported α‐polymorph. Instead, the vapor phase above α‐H2CO3 corresponds to CH3OCO2H, which sheds new light on the research that has been conducted on molecular H2CO3 over the last decades.
Catalytic Enantioselective Addition of Thioacids to Trisubstituted Nitroalkenes
Authors: Phelan James P. , Patel Evan J. , Ellman Jonathan A.
Published: September 2014

The first example of a catalytic enantioselective addition to and nitronate protonation of trisubstituted nitroalkenes to produce highly enantioenriched products with a tetrasubstituted carbon is reported. Thioacids added in excellent yields and with high enantioselectivities to both activated and unactivated nitroalkenes. The 1,2‐nitrothioacetate products can be readily converted in two steps to biomedically relevant 1,2‐aminosulfonic acids without loss of enantiopurity.
Rhodium(III)‐Catalyzed [3+2] Annulation of 5‐Aryl‐2,3‐dihydro‐1H‐pyrroles with Internal Alkynes through C(sp2)H/Alkene Functionalization
Authors: Zhou Ming‐Bo , Pi Rui , Hu Ming , Yang Yuan , Song Ren‐Jie , Xia Yuanzhi , Li Jin‐Heng
Published: September 2014

This study describes a new rhodium(III)‐catalyzed [3+2] annulation of 5‐aryl‐2,3‐dihydro‐1H‐pyrroles with internal alkynes using a Cu(OAc)2 oxidant for building a spirocyclic ring system, which includes the functionalization of an aryl C(sp2)H bond and addition/protonolysis of an alkene CC bond. This method is applicable to a wide range of 5‐aryl‐2,3‐dihydro‐1H‐pyrroles and internal alkynes, and results in the assembly of the spiro[indene‐1,2′‐pyrrolidine] architectures in good yields with excellent regioselectivities.
Influence of chain length of diol on the swelling behavior of citric acid based pH sensitive polymeric hydrogels: A green approach
Authors: Franklin David S. , Guhanathan Selvam
Published: September 2014

Synthesis of pH‐sensitive hydrogels of citric acid with varying diol units viz., 1,2 Ethane diol, 1,4 butane diol, and 1,6 hexane diol along with methacrylic acid towards the solventless green approach. The formations of the hydrogels were identified using FTIR spectroscopy. Thermal characterization (thermo gravimetric analysis, differential thermal analysis (DTA), and differential scanning calorimetry) and morphology of the synthesized hydrogels have been investigated. Swelling studies of hydrogels in various pH ranging from 4.0 to 10.0 have been investigated. The results of the swelling studies implied that percentage of swelling comparatively higher at neutral pH (7.4) than at acidic and alkaline pH. The inverse relationship was noticed, where ascending the diol units of hydrogel in swelling equilibrium. The hydrogels with the increasing chain length show a noticeable pH sensitivity and which could be considered as smart hydrogel. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41403.
Synthesis, Anticonvulsant Properties, and SAR Analysis of Differently Substituted Pyrrolidine‐2,5‐diones and Piperidine‐2,6‐diones
Authors: Kamiński Krzysztof , Wiklik Beata , Obniska Jolanta
Published: September 2014

Twenty‐two differently substituted 1H‐isoindole‐1,3(2H)‐diones (30–39), 8‐azaspiro[4.5]decane‐7,9‐diones (40–45), and 3‐azaspiro[5.5]undecane‐2,4‐diones (46–51) were synthesized and tested for anticonvulsant activity. These molecules were designed as analogs of previously obtained azaspirosuccinimides (1–24). Initial anticonvulsant screening was performed in mice using the maximal electroshock (MES) and subcutaneous pentylenetetrazole (scPTZ) seizure tests. The acute neurological toxicity was determined applying the minimal motor impairment rotorod test. The preliminary pharmacological results showed that 15 new compounds were effective in at least one animal model of epilepsy, from which nine molecules showed protection against both MES and scPTZ seizures. The structure–activity relationship analysis revealed that anticonvulsant activity was connected closely with the structure of the imide fragment; the most favorable one was the hexahydro‐1H‐isoindole‐1,3(2H)‐dione core. 2‐(2‐Chlorophenyl)hexahydro‐1H‐isoindole‐1,3(2H)‐dione (31) showed activity in the 6‐Hz psychomotor seizure model, which identifies substances effective in partial and therapy‐resistant epilepsy. 3‐[(4‐Chlorophenyl)amino]‐3‐azaspiro[5.5]undecane‐2,4‐dione (47) was active in the in vitro hippocampal slice culture neuroprotection assay.
Silver‐Catalyzed Oxidative Coupling of Aniline and Ene Carbonyl/Acetylenic Carbonyl Compounds: An Efficient Route for the Synthesis of Quinolines
Authors: Zhang Xu , Xu Xuefeng
Published: September 2014

An efficient silver‐mediated coupling of aniline with ene carbonyl/acetylenic carbonyl compounds for the synthesis of quinolines is reported. The transformation is effective for a broad range of substrates, thus enabling the expansion of substituent architectures on the heterocyclic framework. The electronic properties of the substituents on the amine have been investigated. It was found that molecules with both electron‐donating and electron‐withdrawing substituents were suitable substrates for this transformation, and the expected products were obtained in moderate to excellent yields. The use of a single catalytic system to mediate chemical transformations in a synthetic operation is important for the development of new atom‐economic strategies and this strategy is efficient in building complex structures from simple starting materials in an environmentally benign fashion.
Immobilization of a thermostable, fungal recombinant chitinase on biocompatible chitosan beads and the properties of the immobilized enzyme
Authors: Prasad Muthu , Palanivelu Peramachi
Published: September 2014

A recombinant, thermostable fungal chitinase from the thermophilic fungus, Thermomyces lanuginosus, was immobilized on glutaraldehyde cross‐linked chitosan beads, and the properties of the immobilized chitinase were studied. The enzyme was found to be almost completely immobilized in 6 H under shaking condition at 30 °C. The immobilized enzyme exhibited much wider pH optimum and was more stable at alkaline pH values as compared with the soluble enzyme. Both the forms of the enzyme were optimally active at 60 °C and stable at 50 °C for 3 H, and after 3 H, the activity of the soluble enzyme declined sharply, whereas the immobilized chitinase was stable up to 6 H without any significant loss in the activity. KM and Vmax values of the immobilized enzyme were 1.18 mM and 445.7 μmol/Min/mg of protein, respectively. The immobilized enzyme was stable at least for 1 month at 4 °C without any significant loss in the activity.
Comprehensive analysis of PEGylated liposome‐associated proteins relating to the accelerated blood clearance phenomenon by combination with shotgun analysis and conventional methods
Authors: Kawanishi Munehira , Hashimoto Yosuke , Shimizu Taro , Sagawa Ikuko , Ishida Tatsuhiro , Kiwada Hiroshi
Published: September 2014

PEGylated liposome, sterically stabilized by polyethylene glycol (PEG), results in reduced recognition of the liposome by the mononuclear phagocyte system. Recently, we reported regarding the accelerated blood clearance (ABC) phenomenon that PEGylated liposome is cleared very rapidly from blood circulation upon repeated injection. Anti‐PEG IgM production and subsequent complement activation were crucial in causing the ABC phenomenon. However, there still remains the possibility that unknown plasma factors might affect the fate of PEGylated liposome that is subjected to the ABC phenomenon. A label‐free approach to shotgun analysis is a great tool for characterizing proteins in a biological system. In this study, therefore, a shotgun analysis was employed to identify plasma protein bound on PEGylated liposome after the ABC phenomenon was induced in the mouse model. The analysis revealed that immunoglobulin and complement components (C1 and C3) are the major proteins. Subsequent analysis with enzyme‐linked immunosorbent assay and Western blotting showed that the immunoglobulin was IgM and that the complement system was mainly activated via an anti‐PEG IgM‐mediated classical pathway. These results support our earlier assumptions—anti‐PEG IgM and complement activation were the major causes of the ABC phenomenon. Our proposed analytical strategy would be expected to provide useful information for the development and design of the nanocarrier drug delivery system.
Evaluation of radiofrequency exposure levels from multiple wireless installations in population dense areas in Korea
Authors: Kim Byung Chan , Kim Wan‐Ki , Lee Gi‐Tae , Choi Hyung‐Do , Kim Nam , Pack Jeong‐Ki
Published: September 2014

This paper presents the results of measurements from simultaneous human exposure to various radiofrequency (RF) signals at densely populated areas. Measurements were performed at 1260 positions across Korea to determine exposure compliance to electromagnetic fields for the general public. The measured exposure levels were very low compared with the international exposure guidelines and Korean human protection notice. The highest total exposure ratio was 5.1 × 10−3 (approximately 7.1% of guideline limits). Bioelectromagnetics 35:603–606, 2014. © 2014 Wiley Periodicals, Inc.
The spiritual benefits of travel for senior tourists
Authors: Moal–Ulvoas Gaëlle , Taylor Valerie A.
Published: September 2014

This research explores the spiritual benefits of travel for older adults and illustrates how travel meets seniors' self‐actualization and spiritual growth needs. The theoretical point of departure for this research is seniors' quest for meaning and self‐actualization, which act as push factors inducing older adults to travel. Semistructured depth interviews were conducted with 16 retired senior informants who had extensive travel experience. Using an interpretive method, this research reveals four key themes that illustrate the spiritual benefits of travel, thereby extending the growing literature on the motivations of senior travelers. These themes are described as “traveling generates meaning for older adults,” “traveling reveals the self to older adults,” “traveling encourages older adults to better understand others,” and “traveling enables older adults to better understand their relationship to nature”. In sum, the themes describe how older adults may meet their unique spiritual needs through travel and thereby enhance their spiritual development. This research represents one of a few studies examining senior tourism to employ an interpretive method and provides rich insights as a result. This research also extends the emerging research on spirituality in marketing by illustrating how the tourism industry may benefit from a perspective that considers the spiritual benefits of consumption. The research findings suggest that the intangible spiritual benefits of travel, in addition to the tangible benefits, should be highlighted in travel offers and tourism communications targeted to older adults. Copyright © 2014 John Wiley & Sons, Ltd.
Characterisation of gamma delta (γδ) T cell populations in patients with sepsis
Authors: Galley Helen F. , Lowes Damon A. , Thompson Keith , Wilson Naomi D. , Wallace Carol A. , Webster Nigel R.
Published: September 2014

Gamma delta (γδ) T cells contribute to both innate and acquired immune responses during infection. In this pilot study, we measured the in vitro responses of γδT cell populations from patients with sepsis compared to cells from healthy subjects. We also measured production of interferon (IFN)γ. Mononuclear cells were isolated from 10 healthy control subjects and 20 patients with sepsis. Cells were cultured for 7 days with interleukin (IL)‐2 plus the bisphosphonate zoledronic acid which results in indirect cell activation. Flow cytometry was used to characterise the γδT cells and enzyme immunoassay was used to measure IFNγ production. The median [range] proportion of γδT cells in healthy controls after activation was 19.2% [2.0–55.9%], compared to only 0.61% [0.1–3.6%] (P < 0.0001) in patients with sepsis. However, IFNγ levels in culture supernatants were similar in both the patients and healthy subjects. We therefore characterised the cells further by CD27 and CD45RA expression in a additional group of patients and found that the population of γδT cells was mainly CD27 negative which characterised these cells as non‐proliferating effector cells. Our results suggest predominance of a non‐proliferative effector subset of γδT cells in patients with sepsis, which retain functional activity and may contribute towards the host response to inflammation and infection.
Successful retrieval of an entrapped guide wire between a deployed coronary stent and severely calcified vessel wall using excimer laser coronary atherectomy
Authors: Kadohira Tadayuki , Schwarcz Aron I. , Gregorio Joseph De
Published: September 2014

We report the successful retrieval of an entrapped interventional guide wire between a newly deployed coronary stent and severely calcified vessel wall. Using a buddy wire technique, the stent was deployed at high pressure in a culprit lesion of the left anterior descending (LAD) artery. The buddy wire in the LAD artery was entrapped between the deployed stent and severely calcified vessel wall, as it was not removed before stent deployment, and could not be retrieved. Neither balloon catheters nor a microcatheter were able to be advanced behind the stent over the entrapped guide wire. Excimer laser coronary atherectomy (ELCA) was performed within the stent to modify and soften the calcification behind the deployed stent. Consequently, the entrapped guide wire was retrieved successfully and safely. This case illustrates that ELCA can be utilized to retrieve an entrapped guide wire between a deployed stent and calcified vessel wall. © 2014 Wiley Periodicals, Inc.
Effect of Ionic Strength on the Rate of Extracellular Electron Transport in Shewanella oneidensis MR‐1 through Bound‐Flavin Semiquinones
Authors: Kalathil Shafeer , Hashimoto Kazuhito , Okamoto Akihiro
Published: September 2014

Cell‐secreted flavin binds to outer‐membrane c‐type cytochromes (OM c‐Cyts) as a redox cofactor in Shewanella oneidensis MR‐1, generating a semiquinone (Sq) state to enhance the rate of extracellular electron‐transport (EET) process by several orders of magnitude. Here, as ionic strength (Is) is a major factor in stabilizing bound Sq in flavoproteins, we examined the influence of Is on the flavin affinity in OM c‐Cyts to promote Sq formation for enhancing the rate of the EET process. Estimated dissociation constants showed that an increase in Is induces threefold higher Sq formation in OM c‐Cyts. However, the higher Is neither resulted in the larger current production nor current enhancement by flavin addition. Strong Is dependency for the redox potential of heme centers in OM c‐Cyts suggests that Is not only controls the stability of Sq, but also alters coupling constants among redox centers in OM c‐Cyts through structural changes.
One‐Pot Synthesis of CO2‐Responsive Magnetic Nanoparticles with Switchable Hydrophilicity
Authors: Chen Shucheng , Guo Chun Xian , Zhao Qipeng , Lu Xianmao
Published: September 2014

CO2‐responsive nanoparticles have been attracted increasing interest due to their benign reactions with CO2 that give them gas‐switchable properties, which can be easily reversed by mild heating or purging with inert gases. In this work, we have prepared CO2‐responsive magnetic nanoparticles in a simple one‐pot polyol synthesis using diaminoalkanes as the surfactant. The as‐synthesized nanoparticles show excellent reversible aggregation and dispersion in response to alternating purging of N2 and CO2 at room temperature. We found that, among the diaminoalkanes with different chain lengths, 1,8‐diaminooctane is the best candidate for the synthesis of CO2‐responsive nanoparticles, since it allows good dispersity of the nanoparticles after charging with CO2 and also provides effective aggregation and separation following N2 purging. Moreover, the self‐assembly of 1,8‐diaminooctane‐functionalized nanoparticles can be controlled to form linear aggregates with the assistance of N2 and an external magnetic field, demonstrating an effective response to dual stimuli. This work paves the way for the direct synthesis of a wide range of CO2‐responsive nanoparticles.
Competitive Silyl–Prins Cyclization versus Tandem Sakurai–Prins Cyclization: An Interesting Substitution Effect
Authors: Diez‐Varga Alberto , Barbero Héctor , Pulido Francisco J. , González‐Ortega Alfonso , Barbero Asunción
Published: September 2014

Two different mechanism pathways are observed for the reaction of allylsilyl alcohols 1 and aldehydes in the presence of trimethylsilyl trifluoromethanesulfonate (TMSOTf). In the case of allylsilyl alcohols without allylic substituents, the reaction gives dioxaspirodecanes, which are the products of a tandem Sakurai–Prins cyclization. In contrast, allylsilyl alcohols with an allylic substituent (R2≠H) selectively provide oxepanes, thus corresponding to a direct silyl–Prins cyclization. Both types of product are obtained with excellent stereoselectivity. Theoretical studies have been performed to obtain some rationalization for the observed stereoselectivity.
Water‐Soluble Manganese Inorganic Polymers: The Role of Carborane Clusters and Producing Large Structural Adjustments from Minor Molecular Changes
Authors: Fontanet Mònica , Rodríguez Montserrat , Fontrodona Xavier , Romero Isabel , Teixidor Francesc , Viñas Clara , Aliaga‐Alcalde Núria , Matějíček Pavel
Published: September 2014

The reaction of two different carboranylcarboxylate ligands, 1‐CH3‐2‐CO2H‐1,2‐closo‐C2B10H10 or 1‐CO2H‐1,2‐closo‐C2B10H11, with MnCO3 in water leads to polymeric compounds 1 a and 1 b. Both compounds have been characterized by analytical and spectroscopic techniques. Additionally, electrochemical techniques have also been used for compound 1 a. X‐ray analysis revealed substantial differences between both compounds: whereas a six‐coordinated MnII compound with water molecules bridging two MnII centers has been observed for 1 a, a square pyramidal geometry around each MnII ion with terminal water molecules coordinated to each MnII center has been found for 1 b. The observed differences have been attributed to the existence of different substituents, CH3 or H, on one of the carbon atoms of the carboranylcarboxylate ligand. The reaction of 1 a and 1 b with coordinating solvents, such as ethers or Lewis bases, leads to the formation of new compounds with low (mononuclear 4 a, 4 b; dinuclear 3 a, 3 b; and trinuclear 2 a) or high nuclearity (hybrid polymer, 5 a), due to breakage of the corresponding polymer. X‐ray analysis shows that the structural core present in the polymeric materials is not maintained in the resulting compounds, with the exception of trinuclear compound 2 a. The magnetic properties of the compounds studied show weak antiferromagnetic coupling.
Kinetics of carbon dioxide removal by ethylenediamine and diethylenetriamine in aqueous solutions
Authors: Salvi Anuj P. , Vaidya Prakash D. , Kenig Eugeny Y.
Published: September 2014

The polyethyleneamines ethylenediamine (EDA) and diethylenetriamine (DETA) can be considered as promising CO2‐capturing solvents, producible from renewable resources. In the present work, kinetics of CO2 reactions with EDA and DETA was investigated by using a stirred‐cell reactor. The molarities of EDA and DETA in the aqueous solutions were varied from 0.1 to 0.4 and 0.1 to 0.5, correspondingly. The observed pseudo‐first‐order reaction rate constants were measured at 303, 308, and 313 K. The zwitterion and termolecular mechanisms were used to correlate the rate constants. DETA was found to have higher reactivity with CO2 than EDA. Second‐order rate constants for the reactions with EDA and DETA were equal to 15770 and 21480 m3/(kmol s) at 303 K. The activation energy values for EDA and DETA were found to be 57.7 and 30.2 kJ/mol, respectively.
New tools for stimulating dissolution and carbonation of ultramafic mining residues
Authors: Assima Gnouyaro P. , Larachi Faïçal , Molson John , Beaudoin Georges
Published: September 2014

The carbonation of chrysotile and nickel mining residues was studied under ambient laboratory conditions to assess their response under various potential field conditions (pore saturation, watering episodes, temperature, CO2 diffusion, and dissolved oxygen) and to a variety of natural and chemical enhancers (sulfide minerals, brucite, chelate ligands, ionic liquids, and carbonic anhydrase enzyme). Watering of the residues to achieve partial pore saturation was critical for optimal ambient CO2 sequestration by mediating magnesium leaching and CO2 absorption, and by favouring diffusion of gaseous CO2 in pores deep inside the residues. Increasing temperature stimulated CO2 uptake whereas dissolved oxygen triggered undesirable oxidative precipitation and passivation by iron (III) hydroxides. The latter effect was attenuated through addition of depassivation chelates, which impeded iron precipitation and enhanced carbonation under ambient conditions. Pyrite and pyrrhotite, as natural acid generators, failed to improve ambient carbonation by fostering iron passivation to the detriment of mining residue dissolution whereas the use of carbonic anhydrase inhibited formation of magnesium carbonates. Ionic liquids were found suitable for magnesium extraction under alkaline conditions but inefficient for inducing carbonate precipitation. The lower rate of carbonation with hydrophobic ionic liquid‐water mixtures was ascribed to a slower gas‐liquid mass transfer of CO2 to the liquid, which primarily prompted a loss of gas‐liquid interfacial area due to viscous effects and bubble coalescence.
Unilateral and Multilateral Congenital Coronary‐Pulmonary Fistulas in Adults: Clinical Presentation, Diagnostic Modalities, and Management With a Brief Review of the Literature
Authors: Said Salah A. M. , Nijhuis Rogier L. G. , Akker Jeroen W. op den , Takechi Masaki , Slart Riemer H. J. A. , Bos Johannes S. , Hoorntje Caspar R. , Houwelingen K. Gert van , Bakker‐de Boo Mirjam , Braam Richard L. , Vet Thijs M. W. J.
Published: September 2014

Background

Congenital coronary‐pulmonary fistulas (CPFs) are commonly unilateral, but bilateral and multilateral fistulas may occur. In multilateral CPFs, the value of a multidetector computed tomography (MDCT) imaging technique as an adjuvant to coronary angiography (CAG) is eminent. The purpose of this study was to describe the clinical presentation, diagnostic modalities, and management of coincidentally detected congenital CPFs.

Hypothesis

Unilateral and multilateral coronary‐pulmonary fistulas are increasingly detected due to the wide speard application of multidetector computed tomography which might be a supplementary or replacing to conventional coronary angiography.

Methods

We evaluated 14 adult patients with congenital coronary artery fistulas (CAFs) who were identified from several Dutch cardiology departments.

Results

Fourteen adult patients (5 female and 9 male), with a mean age of 57.5 years (range, 24–80 years) had the following abnormal findings: audible systolic cardiac murmur (n = 4), chronic atrial fibrillation (n = 2), nonsustained ventricular tachycardia (n = 1), and cardiomegaly on chest x‐ray (n = 2). Echocardiography revealed normal findings with trivial valvular abnormalities (n = 9), depressed left ventricle systolic function (n = 3), and severe mitral regurgitation and atrial dilatation (n = 2). The findings in the rest of the patients were unremarkable. CAG and MDCT were used as a diagnostic imaging techniques either alone (CAG, n = 6; MDCT, n = 1) or in combination (n = 7). Single modality and multimodality diagnostic methods revealed 22 fistulas including CPFs (n = 15), coronary cameral fistulas terminating into the right (n = 2) and the left atrium (n = 1), and systemic‐pulmonary fistulas (n = 4). Of all of the fistulas, 10 were unilateral, 6 were bilateral, and 6 was hexalateral. 13N‐ammonia positron emission tomography‐computed tomography was performed in 3 patients revealing decreased myocardial perfusion reserve.

Conclusions

CAG remains the gold standard for detection of CPFs. An adjuvant technique using MDCT provides full anatomical details of the fistulas.
Exploring the Active Conformation of Cyclohexane Carboxylate Positive Allosteric Modulators of the Type 4 Metabotropic Glutamate Receptor
Authors: Rovira Xavier , Harrak Youssef , Trapero Ana , González‐Bulnes Patricia , Malhaire Fanny , Pin Jean‐Philippe , Goudet Cyril , Giraldo Jesús , Llebaria Amadeu
Published: September 2014

The active conformation of a family of metabotropic glutamate receptor subtype 4 (mGlu4) positive allosteric modulators (PAMs) with the cyclohexane 1,2‐dicarboxylic scaffold present in cis‐2‐(3,5‐dichlorophenylcarbamoyl)cyclohexanecarboxylic acid (VU0155041) was investigated by testing structurally similar six‐membered ring compounds that have a locked conformation. The norbornane and cyclohexane molecules designed as mGlu4 conformational probes and the enantiomers of the trans diastereomer were computationally characterized and tested in mGlu4 pharmacological assays. The results support a VU0155041 active conformation, with the chair cyclohexane having the aromatic amide substituent in an axial position and the carboxylate in an equatorial position. Moreover, the receptor displays enantiomeric discrimination of the chiral PAMs. The constructed pharmacophore characterized a highly constrained mGlu4 allosteric binding site, thus providing a step forward in structure‐based drug design for mGlu4 PAMs.
Nature‐inspired soft computing for financial option pricing using high‐performance analytics
Authors: Thulasiram Ruppa K. , Thulasiraman Parimala , Prasain Hari , Jha Girish K.
Published: September 2014

High‐performance computing has witnessed the push towards computer hardware design in the past decade. Many real world problems are both data and compute intensive. Designing efficient algorithms is important to make effective use of the hardware resources for fast data analysis. Finance is one application that will benefit from these supercomputers. Options are instruments that give opportunity to profit from market movements without making large investments. However, understanding the asset price behavior and making a decision to enter into an option contract is quite challenging, called option pricing problem, because underlying asset price might vary violently. In this paper, we propose a nature‐inspired soft computing, meta‐heuristic, particle swarm optimization (PSO) algorithm to price options. We modify the PSO algorithm and incorporate varying volatility parameters to price options. The proposed algorithm, PSO with Varying Volatility (PSOwVV), is experimented with various PSO and financial parametric conditions. We also develop a parallel PSOwVV algorithm and implement on a distributed shared memory multi‐core machine. We show that the parallel algorithm performs well when the number of particles is linearly proportional to the number of processors. The parallel algorithm achieves a speedup of approximately 20× with 64 particles on a four node hybrid cluster. Copyright © 2014 John Wiley & Sons, Ltd.
The Role of Functional Moieties on Carbon Nanotube Surfaces in Solar Energy Conversion
Authors: Roy D. , Tiwari N. , Mukhopadhyay K. , Shripathi T. , Saxena A. K.
Published: September 2014

An easily dispersible multiwalled carbon nanotube (MWCNT) derivative is prepared, and provides a platform for the synthesis of the phenyl butyric acid methyl ester (PCBM) analog. The carbene addition reaction of MWCNTs makes derivatives that are less soluble in organic solvents; by exploiting this differential solubility, PCBM analogs can be separated from the unreacted functionalized MWCNTs. Our experimental evidences indicate that it is the unique properties of the butyric acid methyl ester moiety that makes the acceptor material perform better in organic photovoltaics (OPVs). Studying the combination of the butyric acid methyl ester moiety and the deagglomerated functionalized MWCNT structures provides us an insight into nanoscale charge transfer and transportation inside the donor–acceptor domain. It is demonstrated that a strong structure–property relationship exists for the functionalized MWCNTs, which enables us to correlate the functionality on the carbon nanostructures with performance in OPVs.
Ultrafast FRET to Study Spontaneous Micelle‐to‐Vesicle Transitions in an Aqueous Mixed Surface‐Active Ionic‐Liquid System
Authors: Mandal Sarthak , Kuchlyan Jagannath , Banik Debasis , Ghosh Surajit , Banerjee Chiranjib , Khorwal Vijaykant , Sarkar Nilmoni
Published: September 2014

The spontaneous micelle‐to‐vesicle transition in an aqueous mixture of two surface‐active ionic liquids (SAILs), namely, 1‐butyl‐3‐methylimidazolium n‐octylsulfate ([C4mim][C8SO4]) and 1‐dodecyl‐3‐methylimidazoium chloride ([C12mim]Cl) is described. In addition to detailed structural characterization obtained by using dynamic light scattering, transmission electron microscopy (TEM), and cryogenic TEM techniques, ultrafast fluorescence resonance energy transfer (FRET) from coumarin 153 (C153) as a donor (D) to rhodamine 6G (R6G) as an acceptor (A) is also used to study micelle–vesicle transitions in the present system. Structural transitions of SAIL micelles ([C4mim][C8SO4] or [C12mim]Cl micelles) to mixed SAIL vesicles resulted in significantly increased D–A distances, and therefore, increased timescale of FRET. In [C4mim][C8SO4] micelles, FRET between C153 and R6G occurs on an ultrafast timescale of 3.3 ps, which corresponds to a D–A distance of about 15 Å. As [C4mim][C8SO4] micelles are transformed into mixed micelles upon the addition of a 0.25 molar fraction of [C12mim]Cl, the timescale of FRET increases to 300 ps, which suggests an increase in the D–A distance to 31 Å. At a 0.5 molar fraction of [C12mim]Cl, unilamellar vesicles are formed in which FRET occurs on multiple timescales of about 250 and 2100 ps, which correspond to D–A distances of 33 and 47 Å. Although in micelles and mixed micelles the obtained D–A distances are well correlated with their radius, in vesicles the obtained D–A distance is within the range of the bilayer thickness.
Femtosecond Dynamics in the Lactim Tautomer of Phycocyanobilin: A Long‐Wavelength Absorbing Model Compound for the Phytochrome Chromophore
Authors: Singer Patrick , Fey Sonja , Göller Andreas H. , Hermann Gudrun , Diller Rolf
Published: September 2014

Transient UV/Vis absorption spectroscopy is used to study the primary dynamics of the ring‐A methyl imino ether of phycocyanobilin (PCB‐AIE), which was shown to mimic the far‐red absorbance of the Pfr chromophore in phytochromes (R. Micura, K. Grubmayr, Bioorg. Med. Chem. Lett.­ 1994, 4, 2517–2522). After excitation at 615 nm, the excited electronic state is found to decay with τ1=0.4 ps followed by electronic ground‐state relaxation with τ2=1.2 and τ3=6.7 ps. Compared with phycocyanobilin (PCB), the initial kinetics of PCB‐AIE is much faster. Thus, the lactim structure of PCB‐AIE seems to be a suitable model that could not only explain the bathochromic shift in the ground‐state absorption but also the short reaction of the Pfr as compared to the Pr chromophore in phytochrome. In addition, the equivalence of ring‐A and ring‐D lactim tautomers with respect to a red‐shifted absorbance relative to the lactam tautomers is demonstrated by semiempirical calculations.
Is It All about the Higher Dose? Why Psychoanalytic Therapy Is an Effective Treatment for Major Depression
Authors: Zimmermann Johannes , Löffler‐Stastka Henriette , Huber Dorothea , Klug Günther , Alhabbo Sarah , Bock Astrid , Benecke Cord
Published: September 2014

Empirical evidence for the effectiveness of long‐term psychodynamic psychotherapy (LTPP) in patients with mood disorders is growing. However, it is unclear whether the effectiveness of LTPP is due to distinctive features of psychodynamic/psychoanalytic techniques or to a higher number of sessions. We tested these rival hypotheses in a quasi‐experimental study comparing psychoanalytic therapy (i.e., high‐dose LTPP) with psychodynamic therapy (i.e., low‐dose LTPP) and cognitive–behavioural therapy (CBT) for depression. Analyses were based on a subsample of 77 subjects, with 27 receiving psychoanalytic therapy, 26 receiving psychodynamic therapy and 24 receiving CBT. Depressive symptoms, interpersonal problems and introject affiliation were assessed prior to treatment, after treatment and at the 1‐, 2‐ and 3‐year follow‐ups. Psychoanalytic techniques were assessed from three audiotaped middle sessions per treatment using the Psychotherapy Process Q‐Set. Subjects receiving psychoanalytic therapy reported having fewer interpersonal problems, treated themselves in a more affiliative way directly after treatment and tended to improve in depressive symptoms and interpersonal problems during follow‐up as compared with patients receiving psychodynamic therapy and/or CBT. Multilevel mediation analyses suggested that post‐treatment differences in interpersonal problems and introject affiliation were mediated by the higher number of sessions, and follow‐up differences in depressive symptoms were mediated by the more pronounced application of psychoanalytic techniques. We also found some evidence for indirect treatment effects via psychoanalytic techniques on changes in introject affiliation during follow‐up. These results provide support for the prediction that both a high dose and the application of psychoanalytic techniques facilitate therapeutic change in patients with major depression. Copyright © 2014 John Wiley & Sons, Ltd.

Key Practitioner Message

Psychoanalytic therapy is an effective treatment for major depression, especially in the long run.

The differential effectiveness of psychoanalytic therapy cannot be fully explained by its higher dose.

Distinctive features of psychoanalytic technique (e.g., focusing on patients' dreams, fantasies, sexual experiences or childhood memories) may play an important role in establishing sustained therapeutic change.
A switch‐mode boost DC–DC converter for IR‐drop compensation of charging cable
Authors: Moon Young‐Jin , Yoo Changsik
Published: September 2014

A switch‐mode boost DC–DC converter has been developed to compensate for the IR‐drop because of the finite resistance of a charging cable. The boost ratio of the DC–DC converter is adaptively controlled by an IR‐drop sensing circuit to provide the required voltage level to a battery charger regardless of the cable resistance. Implemented in a 0.18 µm BCDMOS process, the IR‐drop compensating switch‐mode boost DC–DC converter occupies 6.2 mm2 active area and shows the 93.2% peak efficiency. The proposed IR‐drop compensating boost converter can be applied to compensate for the IR‐drop of any type of charging cables. Copyright © 2014 John Wiley & Sons, Ltd.
Single nucleotide polymorphisms of ataxia telangiectasia mutated and the risk of papillary thyroid carcinoma
Authors: Song Chang Myeon , Kwon Tack‐Kyun , Park Byung Lae , Ji Yong Bae , Tae Kyung
Published: September 2014

Genetic factors associated with susceptibility to papillary thyroid carcinoma (PTC) are not well known. We evaluated the association between single nucleotide polymorphisms (SNPs) of ataxia telangiectasia mutated (ATM) and the risk of PTC. A total of 437 histologically confirmed PTC cases and 184 cancer‐free controls without thyroid nodules were recruited. Genotypes with respect to five ATM SNPs (rs189037, rs664677, rs373759, rs664143, and rs4585) were determined by the TaqMan assay, and odds ratios and 95% confidence intervals were obtained by logistic regression analysis. Linkage disequilibria and haplotypes were examined from the genotype data. When evaluated separately the genotype distributions of the five ATM SNPs were similar in the PTC cases and controls. Three ATM SNPs (rs373759, rs664143, and rs4585) were found to be in strong linkage disequilibrium (D′ = 1.00, P < 0.001). When the three haplotypes (C‐A‐G), (T‐G‐T), and (C‐G‐T) of these three ATM SNP sites were analyzed, ATM haplotype (C‐G‐T) +/− was associated with a lower risk of PTC than ATM haplotype (C‐G‐T) −/− (P = 0.03) after adjusting for age and gender. Our results suggest that genetic polymorphisms of ATM may play an important role in the development of thyroid cancer in the Korean population. Environ. Mol. Mutagen. 56:70–76, 2015. © 2014 Wiley Periodicals, Inc.
Untersuchung des instationären Grundwasserspiegels in einem Hele‐Shaw‐Gerät
Authors: Kolymbas Dimitrios , Polymerou Iliana
Published: September 2014

Es wird die zweidimensionale, ebene, instationäre Grundwasserabsenkung zu einem Graben anhand kleinmaßstäblicher Modellversuche im Labor untersucht. Die Grundwasserströmung wird in einem Hele‐Shaw‐Gerät als Spaltströmung modelliert. Dabei wird die empirische Formel von Sichardt, die eine Aussage über das Grenzgefälle am Absenkungsrand macht, überprüft.

Investigation of the unsteady groundwater table in a Hele‐Shaw apparatus. We investigate the two‐dimensional, plane, unsteady groundwater lowering towards a trench by means of small‐scale model tests using a Hele‐Shaw apparatus. Doing so, we also check the validity of the empirical equation of Sichardt concerning the limit slope at the boundary of the groundwater table.
Spannungs‐Dehnungs‐Verhalten von Steinsalz aus der flachen und steilen Lagerung
Authors: Missal Christian , Döring Ina , Stahlmann Joachim
Published: September 2014

Um das Verständnis des Spannungs‐Verformungs‐Verhaltens von Clean Halit und Argillaceous Halit von der WIPP zu intensivieren, wurden dem Institut für Grundbau und Bodenmechanik der Technischen Universität Braunschweig 20 Bohrkernproben überlassen. Die gewonnenen Versuchsdaten dienen zur Ableitung von Parametern für höherwertige Stoffmodelle zur Beschreibung des Spannungs‐ und Zeit‐Verformungs‐Verhaltens der beiden Salzfazies. Steinsalz zeigt bei der hier angewandten Dehnungsrate ein sprödes Bruchverhalten. Bei kleinem Manteldruck erreichen die Prüfkörper einen Bruchzustand mit anschließendem Nachbruchbereich. Bereits unterhalb der Bruchspannung kommt es zu einer Volumendehnung, d. h. zu einer Auflockerung des Prüfkörpers durch Dilatanz infolge Mikrorissbildung. Mit Erreichen des Bruchzustands wird die Volumendehnungsrate am größten. Die optischen Unterschiede zwischen den Salzfazies lassen auf eine in Qualität und Quantität unterschiedliche Zusammensetzung von Verunreinigungen und Begleitmineralien schließen. Derartige Inhomogenitäten beeinflussen in Abhängigkeit des Volumenanteils das mechanische Verhalten. Daher ist zu vermuten, dass jeweils unterschiedliche Bruchmechanismen dominieren. Dieser Eindruck kann jedoch durch die Versuche nicht bestätigt werden.

Stress‐strain behavior of rock salt of flat and steep storage. In order to intensify the understanding of the stress‐strain behavior of 'clean halite' and 'argillaceous halite' from the WIPP, the Institute of Soil Mechanics and Foundation Engineering of the Technische Universität Braunschweig were left 20 core samples. The experimental data obtained is used for deriving parameters for high‐quality material models to describe the stress‐ and time‐deformation behavior of the two salt facies. Rock salt shows a brittle fracture behavior at the used strain rate. With a low confining pressure the specimens reach the ultimate strength followed by the typical post failure behavior of rock salt. Already below the ultimate stress state there is a volume expansion observable, i.e. to a loosening of the specimen by dilatancy due to micro‐cracking. The volumetric strain rate will be greatest when the fracture stress is reached. The visual differences between the two facies suggest varying composition of impurities and accompanying minerals. Such inhomogeneities affect the mechanical behavior depending on the volume ratio. It seems that in each case different fracture mechanisms dominate. This impression cannot be confirmed by the experiments.
Stabilisierung ungebundener Tragschichten im Straßen‐ und Wegebau – eine Standortbestimmung
Authors: Vollmert Lars
Published: September 2014

Zur Verbesserung des mechanischen Verhaltens von ungebundenen Tragschichten werden Geokunststoffe eingesetzt, die u. a. eine Bewehrungsfunktion übernehmen. Weisen die eingesetzten Geogitter eine geeignete Materialcharakteristik auf, findet die Bewehrung bereits bei sehr kleinen Verformungen statt. Zur sprachlich‐technischen Differenzierung dieses Gebrauchszustandes wird der Stabilisierungseffekt als Teilmenge der Bewehrungsfunktion verstanden. Die Ausschreibung und Vergabe von Produkten und Maßnahmen kann und sollte auf Basis der bestehenden Regelwerke und CE‐Kennzeichnungen für Bewehrungsprodukte mit geringfügigen Ergänzungen für kleine Verformungen erfolgen. Im Gegensatz zu Bindemittelverbesserungen wird die Wasserdurchlässigkeit nicht beeinflusst und die bewehrten Tragschichten verhalten sich ausgesprochen duktil.

Stabilization of unbound granular layers in road constructions – defining a benchmark. To improve the mechanical performance of unbound granular layers in road constructions, geosynthetics are used for the function of, amongst others, reinforcement by geogrids. As far as the geogrids are characterized by a suitable mechanical specification, the granular layers are reinforced even at very low deformations. For verbal and technical clarification the stabilization effect is understood as part of the reinforcement function. Tenders, bids, acceptances and contracts for products shall be worked out based on technical regulations and CE‐marking documents for reinforcing products with slight additions, taking low strain and serviceability limit states into consideration. In opposite to layers mixed with binders, the water permeability is not influenced by this measure, and geogrid reinforced layers can be characterized by extraordinary ductility.