bluuebunny/crossref_metadata_2025_split huggingface dataset:
Two‐Dimensional Haeckelite NbS2: A Diamagnetic High‐Mobility Semiconductor with Nb4+ Ions
Authors: Ma Yandong , Kuc Agnieszka , Jing Yu , Philipsen Pier , Heine Thomas 
Published: June 2017

AbstractIn all known Group 5 transition‐metal dichalcogenide monolayers (MLs), the metal centers carry a spin, and their ground‐state phases are either metallic or semiconducting with indirect band gaps. Here, on grounds of first‐principles calculations, we report that the Haeckelite polytypes 1S‐NbX2 (X=S, Se, Te) are diamagnetic direct‐band‐gap semiconductors even though the Nb atoms are in the 4+ oxidation state. In contrast, 1S‐VX2 MLs are antiferromagnetically coupled indirect‐band‐gap semiconductors. The 1S phases are thermodynamically and dynamically stable but of slightly higher energy than their 1H and 1T ML counterparts. 1S‐NbX2 MLs are excellent candidates for optoelectronic applications owing to their small band gaps (between 0.5 and 1 eV). Moreover, 1S‐NbS2 shows a particularly high hole mobility of 2.68×103 cm2 V−1 s−1, which is significantly higher than that of MoS2 and comparable to that of WSe2.
Electronic Origin of the Competitive Mechanisms in the Thermal Activation of Methane by the Heteronuclear Cluster Oxide [Al2ZnO4].+
Authors: Zhou Shaodong , Yue Lei , Schlangen Maria , Schwarz Helmut 
Published: June 2017

AbstractThe thermal gas‐phase reactions of [Al2ZnO4].+ with methane have been explored by using FT‐ICR mass spectrometry complemented by high‐level quantum chemical calculations. Two competitive mechanisms, that is, hydrogen‐atom transfer (HAT) and proton‐coupled electron transfer (PCET) are operative. Interestingly, while the HAT process is influenced by the polarity of the transition structure, both the ionic nature of the metal–oxygen bond and the structural rigidity of the cluster oxide affect the PCET pathway. As compared to the previously reported homonuclear [Al2O3].+ and [ZnO].+, the heteronuclear oxide [Al2ZnO4].+ exhibits a much higher chemoselectivity towards methane. The electronic origins of the doping effect have been explored.
Vanadium Chloroperoxidases: The Missing Link in the Formation of Chlorinated Compounds and Chloroform in the Terrestrial Environment?
Authors: Wever Ron , Barnett Phil 
Published: June 2017

AbstractIt is well established that the majority of chlorinated organic substances found in the terrestrial environment are produced naturally. The presence of these compounds in soils is not limited to a single ecosystem. Natural chlorination is also a widespread phenomenon in grasslands and agricultural soils typical for unforested areas. These chlorinated compounds are formed from chlorination of natural organic matter consisting of very complex chemical structures, such as lignin. Chlorination of several lignin model compounds results in the intermediate formation of trichloroacetyl‐containing compounds, which are also found in soils. These decay, in general, through a haloform‐type reaction mechanism to CHCl3. Upon release into the atmosphere, CHCl3 will produce chlorine radicals through photolysis, which will, in turn, lead to natural depletion of ozone. There is evidence that fungal chloroperoxidases able to produce HOCl are involved in the chlorination of natural organic matter. The objective of this review is to clarify the role and source of the various chloroperoxidases involved in the natural formation of CHCl3.
Stabilization of Stochastic Coupled Systems With Time Delay Via Feedback Control Based on Discrete‐Time State Observations
Authors: Wu Yongbao , Huo Mengjie , Li Wenxue 
Published: June 2017

AbstractIn this paper, the stabilization of stochastic coupled systems (SCSs) with time delay via feedback control based on discrete‐time state observations is investigated. We use the discrete‐time state feedback control to stabilize stochastic coupled systems with time delay. Moreover, by employing Lyapunov method and graph theory, the upper bound of the duration between two consecutive state observations is obtained and some criteria are established to guarantee the stabilization in sense of
‐stability and mean‐square asymptotic stability of SCSs with time delay via feedback control based on discrete‐time state observations. In addition, to verify the theoretical results, stochastic coupled oscillators with time delay are performed. At last, a numerical example is given to illustrate the applicability and effectiveness of our analytical results.
A colorimetric and fluorogenic probe for bisulfite using benzopyrylium as the recognition unit
Authors: Zhang Yun , Zhang Xiangwen , Yang Xiao‐Feng , Zhang Juan 
Published: June 2017

AbstractA coumarin–benzopyrylium (CB) platform has been developed for the colorimetric and fluorogenic detection of bisulfite. The proposed probe utilizes coumarin as the fluorophore and positively charged benzopyrylium as the reaction site. The method employs the nucleophilic addition of bisulfite to the benzopyrylium moiety of CB to inactivate the electron‐deficient oxonium ion. The driving force for photo‐induced electron transfer is considerably diminished, thereby promoting the emission intensity of the coumarin fluorophore. The fluorescence intensity at 510 nm is linear with bisulfite concentration over a range of 0.2–7.5 μM with a detection limit of 42 nM (3δ). CB shows a rapid response (within 30 s) and high selectivity and sensitivity for bisulfite. Preliminary studies show that CB has great potential for bisulfite detection in real samples and in living cells.
Spectrofluorimetric determination of atenolol from human urine using high‐affinity molecularly imprinted solid‐phase extraction sorbent
Authors: Gorbani Yagoup , Yılmaz Hüma , Basan Hasan 
Published: June 2017

AbstractThis study presents a novel, sensitive and selective molecularly imprinted solid‐phase extraction (MISPE)–spectrofluorimetric method for the removal and determination of atenolol from human urine. Molecularly imprinted and non‐imprinted polymers were synthesized thermally using a radical chain polymerization technique and used as solid‐phase extraction sorbents. Acrylic acid ethylene glycol dimethacrylate, dibenzoyl peroxide and dichloroethane were used as a functional monomer, cross‐linker, initiator and porogen, respectively. The calibration curve was in the range of 0.10–2.0 μg/ml for the developed method. Limit of detection and limit of quantification values were 0.032 and 0.099 μg/ml, respectively. Owing to the selectivity of the MISPE technique and the sensitivity of spectrofluorimetry, trace levels of atenolol have been successfully determined from both organic and aqueous media. Relatively high imprinting factor (4.18) and recovery results (74.5–75.3%) were obtained. In addition, intra‐ and interday precision values were 0.38–1.03% and 0.47–2.05%, respectively, proving the precision of the proposed method. Thus, a selective, sensitive and simple MISPE–spectrofluorimetric method has been developed and applied to the direct determination of atenolol from human urine.
Winding paths: Ambivalence in consumers' buying processes
Authors: Sipilä Jenni , Sundqvist Sanna , Tarkiainen Anssi 
Published: June 2017

AbstractThis paper investigates ambivalence in the buying process. The existing literature has rarely studied ambivalence in longitudinal processes and has therefore not been able to capture its dynamics. Those studies that have studied ambivalence longitudinally have focused on general attitudinal ambivalence rather than its subtypes (cognitive, affective, and intercomponent ambivalence) and have therefore ignored some of the more detailed dynamics. Hence, this study addresses these different types of ambivalence longitudinally, exploring what these different ambivalences consist of, what their roles are in the buying process, and how they occur under different types of involvement conditions. A longitudinal video diary method is used in conjunction with a multimodal analysis technique to explore not only the verbally expressed aspects of ambivalence but also its nonverbal expression, which further reveals differences between different types of ambivalence. The findings suggest that cognitive ambivalence involves conflicting evaluations of utilitarian brand and product aspects and is resolved through more effortful mechanisms, whereas intercomponent ambivalence involves conflicting evaluations of varying utilitarian, hedonic, and symbolic brand and product aspects and is resolved through both more and less effortful mechanisms. Finally, affective ambivalence involves conflicting anticipations about the outcome of the buying process but is not resolved through similarly clear mechanisms. As the key outcome of the exploration, propositions and a synthesising framework about the different types of ambivalence in the buying process are developed for future research. This paper hence contributes to the ambivalence literature and offers managerial implications especially for marketers of multifaceted and high‐involvement products.
Probing Human Telomeric DNA and RNA Topology and Ligand Binding in a Cellular Model by Using Responsive Fluorescent Nucleoside Probes
Authors: Manna Sudeshna , Panse Cornelia H. , Sontakke Vyankat A. , Sangamesh Sarangamath , Srivatsan Seergazhi G. 
Published: June 2017

AbstractThe development of biophysical systems that enable an understanding of the structure and ligand‐binding properties of G‐quadruplex (GQ)‐forming nucleic acid sequences in cells or models that mimic the cellular environment would be highly beneficial in advancing GQ‐directed therapeutic strategies. Herein, the establishment of a biophysical platform to investigate the structure and recognition properties of human telomeric (H‐Telo) DNA and RNA repeats in a cell‐like confined environment by using conformation‐sensitive fluorescent nucleoside probes and a widely used cellular model, bis(2‐ethylhexyl) sodium sulfosuccinate reverse micelles (RMs), is described. The 2′‐deoxy and ribonucleoside probes, composed of a 5‐benzofuran uracil base analogue, faithfully report the aqueous micellar core through changes in their fluorescence properties. The nucleoside probes incorporated into different loops of H‐Telo DNA and RNA oligonucleotide repeats are minimally perturbing and photophysically signal the formation of respective GQ structures in both aqueous buffer and RMs. Furthermore, these sensors enable a direct comparison of the binding affinity of a ligand to H‐Telo DNA and RNA GQ structures in the bulk and confined environment of RMs. These results demonstrate that this combination of a GQ nucleoside probe and easy‐to‐handle RMs could provide new opportunities to study and devise screening‐compatible assays in a cell‐like environment to discover GQ binders of clinical potential.
Granulomatous hypophysitis: rare disease with challenging diagnosis
Authors: Elgamal Mohannad E. , Mohamed Rawia M. H. , Fiad Tarek , Elgamal Essam A. 
Published: June 2017

Key Clinical MessageGranulomatous hypophysitis is rare pathology that mimics pituitary adenoma. Diagnosis is only confirmed by histopathology examination. Trans‐sphenoidal surgery is considered diagnostic when descent tissue specimen is obtained and therapeutic by decompressing optic pathway and the sella. Pathological findings always reveal granulomatous areas, multinucleated giant cells, plasma cells, and lymphocytes.
Twofold Electrochemical Amination of Naphthalene and Related Arenes
Authors: Möhle Sabine , Herold Sebastian , Richter Frank , Nefzger Hartmut , Waldvogel Siegfried R. 
Published: June 2017

AbstractThe twofold electrochemical amination reaction of polycyclic arenes, such as naphthalene (4), via Zincke intermediates is demonstrated for the first time. The installation of nitrogen functionalities occurs regioselectively in positions 1 and 5 of naphthalene (4). The key for this electroconversion is boron‐doped diamond as the anode material. The method of the multi‐amination reaction is expanded to other aromatic substrates. A detailed study is provided, covering electrolysis parameters such as anode material, electrolyte system, current density, separator, and so forth. Despite the moderate yields, this approach offers the first direct electrosynthetic access to diaminated products.
Lanthanum‐Based Compounds: Electronic Band‐Gap‐Dependent Electrocatalytic Materials for Oxygen Reduction Reaction
Authors: Gu Weiwei , Song Ye , Liu Jingjun , Wang Feng 
Published: June 2017

AbstractThe electronic energy level of lanthanum compounds plays an important role in the oxygen reduction reaction (ORR) electrocatalytic process. In this work, three lanthanum compounds, LaOHCO3, La2O2CO3, and La2O3, have been synthesized through an in situ urea hydrolysis method, followed by annealing at different temperatures. Among these lanthanum compounds, the layer‐structured La2O2CO3 has the smallest band gap and moderate values of the conduction band (CB) and valence band (VB). Electrochemical measurements in 0.1 m KOH solution have shown that, compared with the other catalysts, La2O2CO3 exhibits the best electrocatalytic activity with the lowest H2O2 production and highest durability for ORR, which proves the close correlation between electronic energy level and electrocatalytic ORR activity. During the ORR process over La2O2CO3, some covalent electrons from the VB are first excited to the CB and then transfer to the unoccupied π*2p orbitals of an active oxygen molecule, leading to strengthened oxygen adsorption and promotion of the reduction of oxygen. Moreover, La2O2CO3 has an ability to chemically disproportionate hydrogen peroxide (to give HO2−), and the produced HO2− at the energy level of O2/HO2− can undergo prompt chemical disproportionation into O2 and OH−. The O2 generated at this stage is adsorbed on the catalyst surface, which can be utilized for further oxygen reduction.
Coordination‐Driven Folding in Multi‐ZnII‐Porphyrin Arrays Constructed on a Pillar[5]arene Scaffold
Authors: Trinh Thi Minh Nguyet , Nierengarten Iwona , Ben Aziza Haifa , Meichsner Eric , Holler Michel , Chessé Matthieu , Abidi Rym , Bijani Christian , Coppel Yannick , Maisonhaute Emmanuel , Delavaux‐Nicot Béatrice , Nierengarten Jean‐François 
Published: June 2017

AbstractPillar[5]arene derivatives bearing peripheral porphyrin subunits have been efficiently prepared from a deca‐azide pillar[5]arene building block (17) and ZnII‐porphyrin derivatives bearing a terminal alkyne function (9 and 16). For the resulting deca‐ZnII‐porphyrin arrays (18 and 20), variable temperature NMR studies revealed an intramolecular complexation of the peripheral ZnII‐porphyrin moieties by 1,2,3‐triazole subunits. As a result, the molecules adopt a folded conformation. This was further confirmed by UV/Vis spectroscopy and cyclic voltammetry. In addition, we have also demonstrated that the coordination‐driven unfolding of 18 and 20 can be controlled by an external chemical stimulus. Specifically, addition of an imidazole derivative (22) to solution of 18 or 20 breaks the intramolecular coordination at the origin of the folding. The resulting molecular motions triggered by the addition of the imidazole ligand mimic the blooming of a flower.
On the importance of retaining stresses and strains in repositioning computational biomechanical models of the cervical spine
Authors: Boakye‐Yiadom Solomon , Cronin Duane S. 
Published: June 2017

AbstractHuman body models are created in a specific posture and often repositioned and analyzed without retaining stresses that result from repositioning. For example, repositioning a human neck model within the physiological range of motion to a head‐turned posture prior to an impact results in initial stresses within the tissues distracted from their neutral position. The aim of this study was to investigate the effect of repositioning on the subsequent kinetics, kinematics, and failure modes, of a lower cervical spine motion segment, to support future research at the full neck level.Repositioning was investigated for 3 modes (tension, flexion, and extension) and 3 load cases. The model was repositioned and loaded to failure in one continuous load history (case 1), or repositioned then restarted with retained stresses and loaded to failure (case 2). In case 3, the model was repositioned and then restarted in a stress‐free state, representing current repositioning methods. Not retaining the repositioning stresses and strains resulted in different kinetics, kinematics, or failure modes, depending on the mode of loading. For the motion segment model, the differences were associated with the intervertebral disc fiber reorientation and load distribution, because the disc underwent the largest deformation during repositioning.This study demonstrated that repositioning led to altered response and tissue failure, which is critical for computational models intended to predict injury at the tissue level. It is recommended that stresses and strains be included and retained for subsequent analysis when repositioning a human computational neck model.
Towards a generic multilayer negotiation framework for efficient application provisioning in the cloud
Authors: Omezzine Aya , Bellamine Ben Saoud Narjes , Tazi Said , Cooperman Gene 
Published: June 2017

SummaryThe cloud market is nowadays a complex environment where cloud application providers need to maximize their monetary profit and end users look for the most efficient services with the lowest prices. For efficient cloud provisioning, both providers and users should be satisfied in spite of their conflicting needs. Negotiation is the most flexible solution to solve conflicts and enable reaching win‐win agreements. Cloud application provisioning has 2 main properties that highly impact the negotiation decision‐making models: (1) The interdependence between the business layer and the resource layer, and (2) the dynamic provisioning context (eg, negotiators’ preferences and application scheduler). Despite the importance of these 2 properties, the current negotiation models do not take these properties into account. This paper addresses both issues. We propose a multilayer negotiation framework, which also encompasses the potential for dynamic provisioning context. For that, we propose, first, a generic negotiation model dedicated to cloud provisioning. And second, we present its instantiation among cloud layers for efficient SaaS provisioning, to maximize provider profit and increase user satisfaction. The experiments show the benefits of adding negotiation to the provisioning process by improving it for provider profit, number of accepted requests, and client satisfaction.
Crack evolution process of window glass under radiant heating
Authors: Chen Haodong , Wang Yu , Zhang Yi , Wang Qingsong , Zhao Han , Shao Guangzheng , Su Yanfei , Sun Jinhua , He Linghui 
Published: June 2017

SummaryWindow glass breakage has a significant impact on the compartment fire development being sometimes a weak link for fire safety design. This work focuses on the process of crack evolution of window glass in a fire environment. A total of 11 experiments were conducted in a box apparatus by changing heating rate of a heat source. The box apparatus is an enclosed compartment, which includes the heat source, assembled boxes, and glass pane. Crack time, temperature field, breaking stress, crack evolution, and fall‐out of the glass panes are presented. Main and secondary fractures are defined and illustrated in the process of crack evolution. Average time to the first, second, and third main fractures decreased as the heating rate of heat source increased. The average breaking stress was 71.14 MPa for float glass at the time of first main fracture. The crack evolution process was very complicated. Cracks initiated at an edge and propagated towards other edges for main fractures. Multiple cracks were joined together to form cracked glass islands. The fall‐out of cracked glass islands under radiant heating was more difficult than that under real fire scenarios.
TGF‐β signaling directly regulates transcription and functional expression of the electrogenic sodium bicarbonate cotransporter 1, NBCe1 (SLC4A4), via Smad4 in mouse astrocytes
Authors: Khakipoor Shokoufeh , Ophoven Christian , Schrödl‐Häußel Magdalena , Feuerstein Melanie , Heimrich Bernd , Deitmer Joachim W. , Roussa Eleni 
Published: June 2017

AbstractThe electrogenic sodium bicarbonate cotransporter NBCe1 (SLC4A4) expressed in astrocytes regulates intracellular and extracellular pH. Here, we introduce transforming growth factor beta (TGF‐β) as a novel regulator of NBCe1 transcription and functional expression. Using hippocampal slices and primary hippocampal and cortical astrocyte cultures, we investigated regulation of NBCe1 and elucidated the underlying signaling pathways by RT‐PCR, immunoblotting, immunofluorescence, intracellular H(+) recording using the H(+) ‐sensitive dye 2′,7′‐bis‐(carboxyethyl)‐5‐(and‐6)‐carboxyfluorescein, mink lung epithelial cell (MLEC) assay, and chromatin immunoprecipitation. Activation of TGF‐β signaling significantly upregulated transcript, protein, and surface expression of NBCe1. These effects were TGF‐β receptor‐mediated and suppressed following inhibition of JNK and Smad signaling. Moreover, 4‐aminopyridine (4AP)‐dependent NBCe1 regulation requires TGF‐β. TGF‐β increased the rate and amplitude of intracellular H+ changes upon challenging NBCe1 in wild‐type astrocytes but not in cortical astrocytes from Slc4a4‐deficient mice. A Smad4 binding sequence was identified in the NBCe1 promoter and Smad4 binding increased after activation of TGF‐β signaling. The data show for the first time that NBCe1 is a direct target of TGF‐β/Smad4 signaling. Through activation of the canonical pathway TGF‐β acts directly on NBCe1 by binding of Smad4 to the NBCe1 promoter and regulating its transcription, followed by increased protein expression and transport activity.
The novel synthetic microneurotrophin BNN27 protects mature oligodendrocytes against cuprizone‐induced death, through the NGF receptor TrkA
Authors: Bonetto Giulia , Charalampopoulos Ioannis , Gravanis Achille , Karagogeos Domna 
Published: June 2017

AbstractBNN27, a member of a chemical library of C17‐spiroepoxy derivatives of the neurosteroid DHEA, has been shown to regulate neuronal survival through its selective interaction with NGF receptors (TrkA and p75NTR), but its role on glial populations has not been studied. Here, we present evidence that BNN27 provides trophic action (rescue from apoptosis), in a TrkA‐dependent manner, to mature oligodendrocytes when they are challenged with the cuprizone toxin in culture. BNN27 treatment also increases oligodendrocyte maturation and diminishes microglia activation in vitro. The effect of BNN27 in the cuprizone mouse model of demyelination in vivo has also been investigated. In this model, that does not directly involve the adaptive immune system, BNN27 can protect from demyelination without affecting the remyelinating process. BNN27 preserves mature oligodendrocyte during demyelination, while reducing microgliosis and astrogliosis. Our findings suggest that BNN27 may serve as a lead molecule to develop neurotrophin‐like blood–brain barrier (BBB)‐permeable protective agents of oligodendrocyte populations and myelin, with potential applications in the treatment of demyelinating disorders.