bluuebunny/crossref_metadata_2025_split huggingface dataset:
Adaptive fault tolerant control for a class of multi‐input multi‐output nonlinear systems with both sensor and actuator faults
Authors: Jin Xu 
Published: May 2017

SummaryCompared with the fault diagnosis, detection, and isolation literature, very few results are available to discuss control algorithms directly for multi‐input multi‐output nonlinear systems with both sensor and actuator faults in the fault tolerant control literature. In this work, we present a fault tolerant control algorithm to address the system output stabilization problem for a class of multi‐input multi‐output nonlinear systems with both parametric and nonparametric uncertainties, subject to sensor and actuator faults that can be both multiplicative and additive. All elements of the sensor measurements and actuator components can be faulty. Besides, the control input gain function is not fully known. Backstepping method is used in the analysis and control design. We show that under the proposed control scheme, uniformly ultimate boundedness of the system output is guaranteed, while all closed‐loop system signals stay bounded. In the cases where the sensor faults are only multiplicative, exponential convergence of the system state variables into small neighbourhoods around zero is guaranteed. An illustrative example on a robot manipulator model is presented in the end to further demonstrate the effectiveness of the proposed control scheme.
A recursive technique for tracking the feasible parameter set in bounded error estimation
Authors: Casini Marco , Garulli Andrea , Vicino Antonio 
Published: May 2017

SummaryIn this paper, a new recursive algorithm is proposed for tracking parameter changes of a time‐varying linear system. Since a bounded error approach is adopted for both modeling the measurement noise and the parameter change process, the problem addressed amounts to the design of a procedure for updating an estimate of the feasible parameter set. The approximating regions considered are in the form of outbounding orthotopes. The novelty of the approach lies in the use of a selection technique which keeps track only of a special subset of the constraints defining the feasible set. These inequalities represent the binding constraints of suitable linear programs of limited size. The devised algorithm is tested on several numerical examples, showing remarkable performance both in computational burden, which is comparable to that of classical recursive estimation algorithms like recursive least squares (RLS) and quality of the set estimate as compared to alternative techniques available in the literature.
Nanostructures to Engineer 3D Neural‐Interfaces: Directing Axonal Navigation toward Successful Bridging of Spinal Segments
Authors: Aurand Emily R. , Usmani Sadaf , Medelin Manuela , Scaini Denis , Bosi Susanna , Rosselli Federica B. , Donato Sandro , Tromba Giuliana , Prato Maurizio , Ballerini Laura 
Published: May 2017

AbstractNeural interfaces are the core of prosthetic devices, such as implantable stimulating electrodes or brain–machine interfaces, and are increasingly designed for assisting rehabilitation and for promoting neural plasticity. Thus, beyond the classical neuroprosthetic concept of stimulating and/or recording devices, modern technology is pursuing toward ideal bio/electrode interfaces with improved adaptability to the brain tissue. Advances in material research are crucial in these efforts and new developments are drawing from engineering and neural interface technologies. Here, a microporous, self‐standing, 3D interface made of polydimethylsiloxane (PDMS) implemented at the interfacing surfaces with novel conductive nanotopographies (carbon nanotubes) is exploited. The scaffold porosity is characterized by 3D X‐ray microtomography. These structures are used to interface axons regenerated from cultured spinal explants and it is shown that engineering PDMS 3D interfaces with carbon nanotubes effectively changes the efficacy of regenerating fibers to target and reconnect segregated explant pairs. An improved electrophysiological performance is shown when the spinal tissue is interfaced to PDMS enriched by carbon nanotubes that may favor the use of our substrates as regenerative interfaces. The materials are implanted in the rat brain and a limited tissue reaction surrounding the implants at 2, 4, and 8 weeks from surgery is reported.
Ultrasensitive Measurement of Ca2+ Influx into Lipid Vesicles Induced by Protein Aggregates
Authors: Flagmeier Patrick , De Suman , Wirthensohn David C. , Lee Steven F. , Vincke Cécile , Muyldermans Serge , Knowles Tuomas P. J. , Gandhi Sonia , Dobson Christopher M. , Klenerman David 
Published: May 2017

AbstractTo quantify and characterize the potentially toxic protein aggregates associated with neurodegenerative diseases, a high‐throughput assay based on measuring the extent of aggregate‐induced Ca2+ entry into individual lipid vesicles has been developed. This approach was implemented by tethering vesicles containing a Ca2+ sensitive fluorescent dye to a passivated surface and measuring changes in the fluorescence as a result of membrane disruption using total internal reflection microscopy. Picomolar concentrations of Aβ42 oligomers could be observed to induce Ca2+ influx, which could be inhibited by the addition of a naturally occurring chaperone and a nanobody designed to bind to the Aβ peptide. We show that the assay can be used to study aggregates from other proteins, such as α‐synuclein, and to probe the effects of complex biofluids, such as cerebrospinal fluid, and thus has wide applicability.
Practical and theoretical aspects of Wacker oxidation of tolanophanes: Synthesis and characterization of novel diketonic cyclophanes
Authors: Darabi Hossein Reza , Rastgar Saeed , Khatamifar Ehsan , Aghapoor Kioumars , Sayahi Hani , Firouzi Rohoullah 
Published: May 2017

Novel cyclophanes having 1,2‐diketones 2a–c were synthesized by Wacker oxidation of the corresponding tolanophanes 1a–c having various alkyl chain lengths (n = 2–4). Among them, tolanophane 1a with the shortest alkyl chain length (n = 2) having more strained alkyne shows the lowest product selectivity even lower than that of acyclic analogues at various reaction temperatures. In contrast, the oxidation of tolanophane 1b (n = 3) is clean with the highest activity and selectivity of 2b. Theoretical calculations confirm the experimental data. Based on ab initio calculations, the critical step of the reaction pathway is the interaction of oxygen atoms of 1 (in the absence of H2O) with Pd ion of intermediate [PdCl3(1)]− to give [PdCl2(1)] which keeps Pd ion close to the alkyne bond. This step is not observed computationally for 1a because the positions of the oxygen atoms are outside of its central part. This is in good agreement with almost no activity of 1a at room temperature to prove its rigid structure preventing the O…Pd interaction. Nevertheless, the alkyne…Pd interaction of 1b is not detected by NMR measurements which may be due to its too slow interaction at room temperature (35% after 24 h); however, this confirms ab initio calculation data that the preferred coordinating site is oxygen in the reaction pathway. In contrast, cyclic voltammetry measurements distinguish a different behaviour for the palladium complexation of 1. In general, it is found that the stereochemistry of tolanophanes rather than distortion of alkyne bond plays the critical role in the oxidation. The products are new and their structures were characterized.
A versatile synthesis of arylaminotetrazoles by a magnetic Fe@Phendiol@Mn nano‐particle catalyst and its theoretical studies
Authors: Habibi Davood , Heydari Somayyeh , Afsharfarnia Mina , Rostami Zahra 
Published: May 2017

The Fe3O4 magnetic nano‐particles were modified with 1,10‐phenanthroline‐5,6‐diol and the relevant Mn complex (Fe@Phendiol@Mn) synthesized as a nano‐magnetic heterogeneous catalyst to be used for the synthesis of various arylaminotetrazoles from various arylcyanamides and sodium azide in DMF at 120 °C. Also, the nano‐catalyst characterized by different methods such as the elemental analysis (CHN), ICP, FT‐IR, XRD, EDX, SEM, TEM, TG‐DTA, VSM and XPS. In addition, the theoretical study of the Fe@Phendiol@Mn nano‐catalyst was performed using the Gausian software. The calculated results showed that the Gibbs free energy and the standard enthalpy values are negative; therefore the complex is stable. Incidentally, the computational chemistry descriptions including the electronic chemical potential, global hardness, electrophilicity index, energy gap, global softness and electronegativity were calculated.
Functional characterization and tissue expression of marmoset cytochrome P450 2E1
Authors: Uehara Shotaro , Uno Yasuhiro , Tomioka Etsuko , Inoue Takashi , Sasaki Erika , Yamazaki Hiroshi 
Published: May 2017

AbstractCommon marmosets (Callithrix jacchus) have attracted increasing attention as a useful small non‐human primate model in preclinical research. However, studies on marmoset cytochrome P450 (P450) 2E enzyme have scarcely been conducted. In this study, the full‐length cDNA encoding P450 2E1 enzyme was isolated from marmoset livers by reverse transcription (RT)‐polymerase chain reaction (PCR). Marmoset P450 2E1 amino acid sequences were highly identical (>88%) to those of cynomolgus monkey and human P450 2E1 enzymes. Phylogenetic analysis indicated a close evolutionary relationship among marmoset, cynomolgus monkey, and human P450 2E1 enzymes. The tissue expression pattern analyzed by real‐time RT‐PCR and immunoblotting demonstrated that marmoset P450 2E1 mRNA and proteins were predominantly expressed in livers. Marmoset P450 2E1 enzyme heterologously expressed in Escherichia coli catalyzed the hydroxylation of p‐nitrophenol, chlorzoxazone, and theophylline, similar to cynomolgus monkey and human P450 2E1 enzymes. By kinetic analyses, those P450 2E1 enzymes catalyzed p‐nitrophenol hydroxylation with similar affinities and relatively high intrinsic clearance efficiencies. These results indicated that tissue distribution and enzyme‐substrate specificity of marmoset P450 2E1 were similar to cynomolgus monkey and human P450 2E1 enzymes, suggesting that marmosets are a suitable primate model for P450 2E1‐dependent drug and xenobiotic metabolism.
Production of zebrafish cardiospheres and cardiac progenitor cells in vitro and three‐dimensional culture of adult zebrafish cardiac tissue in scaffolds
Authors: Zeng Wendy R. , Beh Siew‐Joo , Bryson‐Richardson Robert J. , Doran Pauline M. 
Published: May 2017

ABSTRACTThe hearts of adult zebrafish (Danio rerio) are capable of complete regeneration in vivo even after major injury, making this species of particular interest for understanding the growth and differentiation processes required for cardiac tissue engineering. To date, little research has been carried out on in vitro culture of adult zebrafish cardiac cells. In this work, progenitor‐rich cardiospheres suitable for cardiomyocyte differentiation and myocardial regeneration were produced from adult zebrafish hearts. The cardiospheres contained a mixed population of c‐kit+ and Mef2c+ cells; proliferative peripheral cells of possible mesenchymal lineage were also observed. Cellular outgrowth from cardiac explants and cardiospheres was enhanced significantly using conditioned medium harvested from cultures of a rainbow trout cell line, suggesting that fish‐specific trophic factors are required for zebrafish cardiac cell expansion. Three‐dimensional culture of zebrafish heart cells in fibrous polyglycolic acid (PGA) scaffolds was carried out under dynamic fluid flow conditions. High levels of cell viability and cardiomyocyte differentiation were maintained within the scaffolds. Expression of cardiac troponin T, a marker of differentiated cardiomyocytes, increased during the first 7 days of scaffold culture; after 15 days, premature disintegration of the biodegradable scaffolds led to cell detachment and a decline in differentiation status. This work expands our technical capabilities for three‐dimensional zebrafish cardiac cell culture with potential applications in tissue engineering, drug and toxicology screening, and ontogeny research. Biotechnol. Bioeng. 2017;114: 2142–2148. © 2017 Wiley Periodicals, Inc.
Rat intersubjective decisions are encoded by frequency‐specific oscillatory contexts
Authors: Schaich Borg Jana , Srivastava Sanvesh , Lin Lizhen , Heffner Joseph , Dunson David , Dzirasa Kafui , de Lecea Luis 
Published: May 2017

AbstractIntroductionIt is unknown how the brain coordinates decisions to withstand personal costs in order to prevent other individuals’ distress. Here we test whether local field potential (LFP) oscillations between brain regions create “neural contexts” that select specific brain functions and encode the outcomes of these types of intersubjective decisions.MethodsRats participated in an “Intersubjective Avoidance Test” (IAT) that tested rats’ willingness to enter an innately aversive chamber to prevent another rat from getting shocked. c‐Fos immunoreactivity was used to screen for brain regions involved in IAT performance. Multi‐site local field potential (LFP) recordings were collected simultaneously and bilaterally from five brain regions implicated in the c‐Fos studies while rats made decisions in the IAT. Local field potential recordings were analyzed using an elastic net penalized regression framework.ResultsRats voluntarily entered an innately aversive chamber to prevent another rat from getting shocked, and c‐Fos immunoreactivity in brain regions known to be involved in human empathy—including the anterior cingulate, insula, orbital frontal cortex, and amygdala—correlated with the magnitude of “intersubjective avoidance” each rat displayed. Local field potential recordings revealed that optimal accounts of rats’ performance in the task require specific frequencies of LFP oscillations between brain regions in addition to specific frequencies of LFP oscillations within brain regions. Alpha and low gamma coherence between spatially distributed brain regions predicts more intersubjective avoidance, while theta and high gamma coherence between a separate subset of brain regions predicts less intersubjective avoidance. Phase relationship analyses indicated that choice‐relevant coherence in the alpha range reflects information passed from the amygdala to cortical structures, while coherence in the theta range reflects information passed in the reverse direction.ConclusionThese results indicate that the frequency‐specific “neural context” surrounding brain regions involved in social cognition encodes outcomes of decisions that affect others, above and beyond signals from any set of brain regions in isolation.
Just‐in‐time, viable, 3‐D avatars from scans
Authors: Feng Andrew , Rosenberg Evan Suma , Shapiro Ari 
Published: May 2017

AbstractWe demonstrate a system that can generate a photorealistic, interactive 3‐D character from a human subject that is capable of movement, emotion, speech, and gesture in less than 20 min without the need for 3‐D artist intervention or specialized technical knowledge through a near automatic process. Our method uses mostly commodity or off‐the‐shelf hardware. We demonstrate the just‐in‐time use of generating such 3‐D models for virtual and augmented reality, games, simulation, and communication. We anticipate that the inexpensive generation of such photorealistic models will be useful in many venues where a just‐in‐time 3‐D reconstructions of digital avatars that resemble particular human subjects is necessary.
Novel Single Lithium‐Ion Conducting Polymer Electrolyte Based on Poly(hexafluorobutyl methacrylate–co–lithium allyl sulfonate) for Lithium‐Ion Batteries
Authors: Ji Pan‐Ying , Fang Jun , Zhang Yi‐Yong , Zhang Peng , Zhao Jin‐Bao 
Published: May 2017

AbstractA new type of single‐ion conducting polymer electrolyte for lithium‐ion batteries, poly(hexafluorobutyl methacrylate‐co‐lithium allyl sulfonate) (P (HFMA‐co‐ASLi)), was firstly prepared by copolymerizing hexafluorobutyl methacrylate (HFMA) and sodium allyl sulfonate (SAS) with a subsequent lithiation process. The prepared polymer electrolyte exhibits high lithium ionic conductivity (10−4 S cm−1 at 80 °C) and excellent cycle performance at high temperature, which could be attributed to the good thermal stability (remains stable up to 300 °C), mechanical properties (7.1 MPa for breaking strength) and high lithium‐ion transference number (0.92). The electrolyte also displays good electrochemical stability (4.6 V). Our obtained results prove that the polymer P (HFMA‐co‐ASLi) is a promising candidate electrolyte for lithium‐ion batteries.
Halogen Substitution Effects on N2O Schiff Base Ligands in Unprecedented Abrupt FeII Spin Crossover Complexes
Authors: Phonsri Wasinee , Macedo David S. , Vignesh Kuduva R. , Rajaraman Gopalan , Davies Casey G. , Jameson Guy N. L. , Moubaraki Boujemaa , Ward Jas S. , Kruger Paul E. , Chastanet Guillaume , Murray Keith S. 
Published: May 2017

AbstractA family of halogen‐substituted Schiff base iron(II) complexes, [FeII(qsal‐X)2], (qsal‐X=5‐X‐N‐(8‐quinolyl)salicylaldimines)) in which X=F (1), Cl (2), Br (3) or I (4) has been investigated in detail. Compound 1 shows a temperature invariant high spin state, whereas the others all show abrupt spin transitions, at or above room temperature, namely, 295 K (X=I) up to 342 K (X=Br), these being some of the highest T1/2 values obtained, to date, for FeII N/O species. We have recently reported subtle symmetry breaking in [FeII(qsal‐Cl)2] 2 with two spin transition steps occurring at 308 and 316 K. A photomagnetic study reveals almost full HS conversion of [FeII(qsal‐I)2] 4 at low temperature (T(LIESST)=54 °K). The halogen substitution effects on the magnetic properties, as well as the crystal packing of the [FeII(qsal‐X)2] compounds and theoretical calculations, are discussed in depth, giving important knowledge for the design of new spin crossover materials. In comparison to the well known iron(III) analogues, [FeIII(qsal‐X)2]+, the two extra π–π and P4AE interactions found in [FeII(qsal‐X)2] compounds, are believed to be accountable for the spin transitions occurring at ambient temperatures.
Photo‐Controlled Waves and Active Locomotion
Authors: Epstein Irving R. , Gao Qingyu 
Published: May 2017

AbstractWaves of chemical concentration, created by the interaction between reaction and diffusion, occur in a number of chemical systems far from equilibrium. In appropriately chosen polymer gels, these waves generate mechanical forces, which can result in locomotion. When a component of the system is photosensitive, light can be used to modulate and control these waves. In this Concept article, we examine various forms of photo‐control of such systems, focusing particularly on the Belousov–Zhabotinsky oscillating chemical reaction. The phenomena we consider include image storage and image processing, feedback‐control and feedback‐induced clustering of waves, and phototropic and photophobic locomotion. Several of these phenomena have analogues in or potential applications to biological systems.
Molybdenum Carbide‐Based Electrocatalysts for Hydrogen Evolution Reaction
Authors: Miao Mao , Pan Jing , He Ting , Yan Ya , Xia Bao Yu , Wang Xin 
Published: May 2017

AbstractElectrocatalytic water splitting is a promising approach for clean and sustainable hydrogen production. Its large‐scale application relies on the availability of low cost and efficient electrocatalysts. Earth‐abundant transition‐metal carbides, especially molybdenum carbides (MoxC), are regarded as potential candidates to replace state‐of‐art but expensive platinum‐group electrocatalysts. In this Review, we summarize recent progress in MoxC electrocatalysts for hydrogen evolution reaction (HER). Nanostructure engineering on the design and preparation of highly efficient electrocatalysts based on MoxC is presented, followed by the comparison and discussion of HER performance on MoxC‐based electrocatalysts. Finally, we offer a perspective on the future development of MoxC‐based electrocatalysts towards HER.
Anchimeric‐Assisted Spontaneous Hydrolysis of Cyanohydrins Under Ambient Conditions: Implications for Cyanide‐Initiated Selective Transformations
Authors: Yerabolu Jayasudhan Reddy , Liotta Charles L , Krishnamurthy Ramanarayanan 
Published: May 2017

AbstractNitrile/cyanide hydrolysis is of importance from the perspective of organic chemistry, especially, prebiotic chemistry. Herein we report that cyanohydrins, generated by the reaction of cyanide with β‐keto acids and γ‐keto‐alcohols, spontaneously hydrolyze under ambient conditions (aqueous medium, RT, and a range of pH). The spontaneous hydrolysis is affected by an intramolecular proton transfer and an intramolecular 5‐exo‐dig attack, but with a twist. In the case of β‐keto acids, the hydrolysis is mediated by the neighboring carboxylic acid group only at pH values less than 7, whereas in the case of γ‐keto‐alcohols the hydrolysis is mediated by the neighboring hydroxyl group only at pH values greater than 7. The results, in combination with previous works, have implications for selective transformations of cyanide‐initiated prebiotic systems chemistry.
A Lanthanide MOF Thin‐Film Fixed with Co3O4 Nano‐Anchors as a Highly Efficient Luminescent Sensor for Nitrofuran Antibiotics
Authors: Zhang Feng , Yao Hua , Chu Tianshu , Zhang Gaowei , Wang Yi , Yang Yangyi 
Published: May 2017

AbstractNitrofurans are a group of widely used veterinary antibiotics, which have been banned due to antibiotics pollution. Development of a rapid and effective method for the detection of nitrofuran antibiotics (NFAs) is an important challenge. Herein, we designed a chemical sensor based on a thin‐film composed of the lanthanide metal‐organic framework (Ln‐MOF) {[Eu2(BCA)3(H2O)(DMF)3]⋅0.5DMF⋅H2O}n (Eu‐BCA, in which BCA is 2,2′‐biquinoline‐4,4′‐dicarboxylate) coated on a cost‐effective stainless steel wire mesh (SSWM) by Co3O4 nano‐anchor fixation method. The MOF coatings were well adhered to the SSWM, resulting in a three‐dimensional porous, flexible, and processable sensor. The structure of the as‐prepared MOF thin‐film was confirmed by powder X‐ray diffraction (PXRD), and the surface morphology was examined by scanning electron microscopy (SEM). Significantly, the Eu‐BCA thin‐film was highly selective and sensitive to NFAs, and yet remained unaffected by other common antibiotics that may be present. The limits of detection for nitrofurantoin (NFT) and nitrofurazone (NFZ) are 0.21 and 0.16 μm, respectively. NFAs were also successfully detected in water from the Pearl River in Guangzhou, and from bovine serum samples. Hence, the reported Ln‐MOF thin‐film is a promising sensor for the detection of NFAs, thereby helping to protect human beings from all manner of hazards that arise from the abuse of antibiotics in livestock breeding.
Homogeneous Electrocatalytic Water Oxidation by a Rigid Macrocyclic Copper(II) Complex
Authors: Wang Jiawei , Huang Haihua , Lu Tongbu 
Published: May 2017

AbstractA copper(II) complex with a rigid macrocyclic ligand has been synthesized and utilized as a homogeneous electrocatalyst for water oxidation in sodium phosphate buffer at pH 12.0. By using a glassy carbon electrode in a 3 h electrolysis, a high current density of 1.3–1.4 mA/cm2 and a turn‐over number of 4 can be obtained with 1.0 mmol•L−1 of the copper catalyst at an overpotential of 750 mV. Kinetic studies revealed that the electrocatalysis with this complex is a single‐site catalysis with proton‐coupled electron transfers. Finally, its possible catalytic mechanism was tentatively proposed.