bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chemische Bildgebung auf der Nanometerskala mittels spitzenverstärkter Raman‐Spektroskopie
Authors: Schmid Thomas , Opilik Lothar , Blum Carolin , Zenobi Renato 
Published: April 2013

AbstractChemische Analysemethoden auf der Nanometerskala sind von zentraler Bedeutung für die Charakterisierung von Nanostrukturen moderner Materialien und biologischer Systeme. Spitzenverstärkte Raman‐Spektroskopie (tip‐enhanced Raman spectroscopy, TERS) kombiniert die chemische Information, welche durch Raman‐Spektroskopie erhalten werden kann, mit der von der oberflächenverstärkten Raman‐Streuung (SERS) bekannten Signalverstärkung und der hohen räumlichen Auflösung der Rasterkraftmikroskopie (AFM) bzw. der Rastertunnelmikroskopie (STM). Dabei wird eine metallische oder metallisierte Spitze in den Fokus eines Lasers gebracht, wodurch ein stark verstärktes elektromagnetisches Feld am Spitzenende resultiert, welches als sehr kleine Lichtquelle für Raman‐spektroskopische Messungen auf der Nanometerskala dient. Dieser Aufsatz beschäftigt sich hauptsächlich mit den Voraussetzungen für eine effiziente Kopplung des Laserlichts an die Spitze sowie den verbliebenen Herausforderungen und Tücken der spitzenverstärkten Raman‐Spektroskopie, welche für die chemische Bildgebung mittels TERS berücksichtigt werden müssen. Beispiele aus aktuellen Publikationen demonstrieren das Potential von TERS für die chemische Bildgebung mit einer räumlichen Auflösung von ca. 10 nm und einer Sensitivität, welche den Nachweis weniger Moleküle ermöglicht in Anwendungen, die von den Materialwissenschaften bis hin zu den Biowissenschaften reichen.
Neue Strategien zur Totalsynthese von anorganischen Nanostrukturen
Authors: Buck Matthew R. , Schaak Raymond E. 
Published: April 2013

AbstractDie rege Nachfrage nach komplexen Nanomaterialien mit präzise kontrollierten Architekturen und Grenzflächen hat zu einer enormen Entwicklung bei innovativen Syntheseverfahren geführt. Dieser Aufsatz beleuchtet Schlüsselstrategien für die chemische Umwandlung und schrittweise Synthese von anorganischen Mehrkomponenten‐Nanostrukturen, wobei existierende Umwandlungsreaktionen im Nanobereich in Klassen eingeordnet werden, die den bei der Synthese von organischen Molekülen verwendeten entsprechen. Ein Schwerpunkt liegt auf der Übertragung von Konzepten aus der Molekülsynthese auf nanoskalige Systeme: Dazu gehören unter anderem Ortsselektivität, Regio‐ und Chemoselektivität, orthogonale Reaktivität, Kupplungsreaktionen, Strategien zum Schützen und Entschützen sowie Verfahren zur Trennung und Aufreinigung. Das so geschaffene Regelwerk stellt ein neues Modell für die “Totalsynthese” von komplexen anorganischen Nanostrukturen dar, dem die Prinzipien von mehrstufigen Totalsynthesen komplexer organischer Molekülverbindungen und Naturstoffe zugrundeliegen.
Emerging Strategies for the Total Synthesis of Inorganic Nanostructures
Authors: Buck Matthew R. , Schaak Raymond E. 
Published: April 2013

AbstractNew synthetic innovations are rapidly being developed to address the demand for complex, next‐generation nanomaterials with rigorously controlled architectures and interfaces. This Review highlights key strategies for the chemical transformation and stepwise synthesis of multicomponent inorganic nanostructures, with the existing nanoscale transformations categorized into classes of reactions that are related to those used in the synthesis of organic molecules. The application of concepts used in molecular synthesis—including site‐selectivity, regio‐ and chemoselectivity, orthogonal reactivity, coupling reactions, protection/deprotection strategies, and procedures for separation and purification—to nanoscale systems is emphasized. Collectively, the resulting synthetic concept represents an emerging model for the synthesis of complex inorganic nanostructures on the basis of the guiding principles that underpin the multistep total synthesis of complex organic molecules and natural products.
Fluorescent Amino Acids: Modular Building Blocks for the Assembly of New Tools for Chemical Biology
Authors: Krueger Andrew T. , Imperiali Barbara 
Published: April 2013

AbstractFluorescence spectroscopy is a powerful tool for probing complex biological processes. The ubiquity of peptide–protein and protein–protein interactions in these processes has made them important targets for fluorescence labeling, and to allow sensitive readout of information concerning location, interactions with other biomolecules, and macromolecular dynamics. This review describes recent advances in design, properties and applications in the area of fluorescent amino acids (FlAAs). The ability to site‐selectively incorporate fluorescent amino acid building blocks into a protein or peptide of interest provides the advantage of closely retaining native function and appearance. The development of an array of fluorescent amino acids with a variety of properties, such as environment sensitivity, chelation‐enhanced fluorescence, and profluorescence, has allowed researchers to gain insights into biological processes, including protein conformational changes, binding events, enzyme activities, and protein trafficking and localization.
A semantic‐aware data generator for ETL workflows
Authors: Du Naiqiao , Ye Xiaojun , Wang Jianmin 
Published: April 2013

SummaryExtract, transform, and load (ETL) processes organized as workflows play an important role in the future data integration for cloud services. ETL designers/administrators need testing data set that is aware of semantics of ETL workflow workloads to evaluate their developed ETL systems. Populating testing ETL systems with meaningful workload data is a difficult task. In this paper, we propose a semantic‐aware data generator for ETL workflows. With given ETL workflow models and workload characterizations, the generator is able to generate synthetic data that capture the semantics of ETL activities. This is carried out by a three‐staged approach. First, we derive expected cardinalities of all the source, intermediate, and target data sets involved in the ETL workflow model with some user‐specified cardinality requirements. Then, with the concept of symbolic test, symbolic data instead of concrete data involved in ETL activities are generated, and semantics of the ETL workflow models are transformed to various constraints over these symbols. At last, concrete data are derived on the basis of resolving constraints. Our generator may facilitate ETL workload test case generation for ETL toolkit performance and function evaluations as well as ETL workflow solution benchmarking. Copyright © 2013 John Wiley & Sons, Ltd.
FrIIDoM: An intelligent driver for automatic configuration in modular display systems
Authors: Bauwens Pieter , Doutreloigne Jan 
Published: April 2013

ABSTRACTFrIIDoM provides an intelligent solution for automatic configuration in modular display systems. Modular displays are displays that consist of small, identical modules. There are a number of ways they can be used: removing the limitation in multiplexability in passive matrix (PM) displays, increasing brightness in PMOLED displays, reducing power consumption in bistable displays, creating large‐scale displays or displays with variable size and shape. For the modules to work together as one display, some initial configuration is required. FrIIdoM consists of four different drivers, with rising levels of complexity, each with their own way of automating the configuration. The simplest systems just make sure that every module is capable of receiving specific image data, irrespective of the shape of the display. The more complex systems are capable of detecting the presence and location of each module, thus detecting the shape of the display. In the created GUI, the user sees a real‐time view of the display configuration, even when modules are added or removed while the display is running. While FrIIDoM is equipped with the drivers to drive a PM LED display, they can be easily changed to incorporate other types of display technologies. Several test modules were created, and we were able to build and successfully drive random display creations. Copyright © 2013 John Wiley & Sons, Ltd.
Effects of clonality on the genetic variability of rare, insular species: the case of Ruta microcarpa from the Canary Islands
Authors: Meloni M. , Reid A. , Caujapé‐Castells J. , Marrero Á. , Fernández‐Palacios J. M. , Mesa‐Coelo R. A. , Conti E. 
Published: April 2013

AbstractMany plant species combine sexual and clonal reproduction. Clonal propagation has ecological costs mainly related to inbreeding depression and pollen discounting; at the same time, species able to reproduce clonally have ecological and evolutionary advantages being able to persist when conditions are not favorable for sexual reproduction. The presence of clonality has profound consequences on the genetic structure of populations, especially when it represents the predominant reproductive strategy in a population. Theoretical studies suggest that high rate of clonal propagation should increase the effective number of alleles and heterozygosity in a population, while an opposite effect is expected on genetic differentiation among populations and on genotypic diversity. In this study, we ask how clonal propagation affects the genetic diversity of rare insular species, which are often characterized by low levels of genetic diversity, hence at risk of extinction. We used eight polymorphic microsatellite markers to study the genetic structure of the critically endangered insular endemic Ruta microcarpa. We found that clonality appears to positively affect the genetic diversity of R. microcarpa by increasing allelic diversity, polymorphism, and heterozygosity. Moreover, clonal propagation seems to be a more successful reproductive strategy in small, isolated population subjected to environmental stress. Our results suggest that clonal propagation may benefit rare species. However, the advantage of clonal growth may be only short‐lived for prolonged clonal growth could ultimately lead to monoclonal populations. Some degree of sexual reproduction may be needed in a predominantly clonal species to ensure long‐term viability.
Investigations on the Phase Transition between CdV2O6 and Cd2V2O7 and Their Photocatalytic Performances
Authors: Li Di , Bai Xiaojuan , Pan Chengsi , Zhu Yongfa 
Published: April 2013

AbstractCdV2O6 and Cd2V2O7 were successfully synthesized by a simple hydrothermal process. The effects of the hydrothermal temperature and pH on the phase transition between CdV2O6 and Cd2V2O7 were investigated in detail. That the Cd2V2O7 phase could transform into CdV2O6 was attributed to polymerization of vanadate in an acidic environment as the V/O ratio increased as the pH decreased. V2O74– was stable in a neutral or alkaline environment at an identical hydrothermal temperature, therefore, the Cd2V2O7 phase was obtained after hydrothermal treatment for 24 h. Because the degree of hydrolysis of NH4Cl increased with increasing temperature in the solution, the increased temperature accelerated the speed of the pH decrease. Therefore, the hydrothermal temperature played an important part in the phase transition between CdV2O6 and Cd2V2O7. CdV2O6 and Cd2V2O7 showed high photocatalytic activity for the degradation of methylene blue under visible‐light irradiation.
A 2D → 3D Polycatenated Metal–Organic Framework: Synthesis, Structure, Magnetic and Catalytic Study
Authors: Sen Rupam , Saha Debraj , Mal Dasarath , Brandão Paula , Rogez Guillaume , Lin Zhi 
Published: April 2013

AbstractA mixed‐ligand 3D metal–organic framework, [Ni(1,2‐cpd)(bpe)(H2O)]n (1) [1,2‐cpd = cis‐cyclopentane‐1,2‐dicarboxylate, bpe = 1,2‐di(4‐pyridyl)ethylene], has been constructed. Topological analysis revealed that the structure is a 3‐c uninodal 2D + 2D → 3D polycatenated net with the Schläfli symbol 63. The compound is catalytically active towards the epoxidation reaction in heterogeneous media. It catalyses almost all types of olefinic substrates with equal efficiency. After reaction it can be recovered quite easily and can be used for further reaction without any loss of activity for several cycles. Variable‐temperature magnetic susceptibility measurement reveals the presence of a weak antiferromagnetic interaction in compound 1.
Electrochemical Detection of Gunshot Residue for Forensic Analysis: A Review
Authors: O'Mahony Aoife M. , Wang Joseph 
Published: April 2013

AbstractCurrent demands for detection of Gunshot Residue (GSR) require a reliable and rapid decentralized detection system with high sensitivity and specificity. This article reviews the use of electrochemical devices for GSR detection over the last 35 years and highlights recent advances associated with the demands of GSR field detection such as portability, speed, cost and power. Anodic stripping voltammetry (ASV) has been widely implemented for the detection of the metallic components of GSR at a variety of working electrodes. Efforts toward the detection of the organic components of GSR have also been reported using cyclic‐ and square‐wave voltammetry. The simultaneous detection of both organic and inorganic GSR constituents has recently been examined to increase the overall information content in a single voltammetric scan. As well as this, exploitation of screen‐printing fabrication allows replacement of conventional electrochemical cells with easy‐to‐use sensor strips Sampling methods for electrochemical GSR analysis are also advancing from acid washes or swabs to simpler abrasive methods which integrate sampling and analysis obviating the need for intermediate processing steps. The latest direction of electrochemical detection of GSR involves chemometric treatment to evaluate data allowing for more objective conclusions and increasing the automation of the system. These advances indicate great promise for investigating firearm‐related crimes, and bring significant changes to the detection of GSR making electroanalysis a powerful tool for decentralized forensic analysis.
Stathmin regulates mutant p53 stability and transcriptional activity in ovarian cancer
Authors: Sonego Maura , Schiappacassi Monica , Lovisa Sara , Dall'Acqua Alessandra , Bagnoli Marina , Lovat Francesca , Libra Massimo , D'Andrea Sara , Canzonieri Vincenzo , Militello Loredana , Napoli Marco , Giorda Giorgio , Pivetta Barbara , Mezzanzanica Delia , Barbareschi Mattia , Valeri Barbara , Canevari Silvana , Colombatti Alfonso , Belletti Barbara , Del Sal Giannino , Baldassarre Gustavo 
Published: April 2013

AbstractStathmin is a p53‐target gene, frequently overexpressed in late stages of human cancer progression. Type II High Grade Epithelial Ovarian Carcinomas (HG‐EOC) represents the only clear exception to this observation. Here, we show that stathmin expression is necessary for the survival of HG‐EOC cells carrying a p53 mutant (p53MUT) gene. At molecular level, stathmin favours the binding and the phosphorylation of p53MUT by DNA‐PKCS, eventually modulating p53MUT stability and transcriptional activity. Inhibition of stathmin or DNA‐PKCS impaired p53MUT–dependent transcription of several M phase regulators, resulting in M phase failure and EOC cell death, both in vitro and in vivo. In primary human EOC a strong correlation exists between stathmin, DNA‐PKCS, p53MUT overexpression and its transcriptional targets, further strengthening the relevance of the new pathway here described. Overall our data support the hypothesis that the expression of stathmin and p53 could be useful for the identification of high risk patients that will benefit from a therapy specifically acting on mitotic cancer cells.
Inhibition of redox/Fyn/c‐Cbl pathway function by Cdc42 controls tumour initiation capacity and tamoxifen sensitivity in basal‐like breast cancer cells
Authors: Chen Hsing‐Yu , Yang Yin M. , Stevens Brett M. , Noble Mark 
Published: April 2013

AbstractWe found that basal‐like breast cancer (BLBC) cells use Cdc42 to inhibit function of the redox/Fyn/c‐Cbl (RFC) pathway, which normally functions to convert small increases in oxidative status into enhanced degradation of c‐Cbl target proteins. Restoration of RFC pathway function by genetic or pharmacological Cdc42 inhibition enabled harnessing of pro‐oxidant effects of low µM tamoxifen (TMX) concentrations – concentrations utilized in trials on multiple tumour types – to suppress division and induce death of BLBC cells in vitro and to confer TMX sensitivity in vivo through oestrogen receptor‐α‐independent mechanisms. Cdc42 knockdown also inhibited generation of mammospheres in vitro and tumours in vivo, demonstrating the additional importance of this pathway in tumour initiating cell (TIC) function. These findings provide a new regulatory pathway that is subverted in cancer cells, a novel means of attacking TIC and non‐TIC aspects of BLBCs, a lead molecule (ML141) that confers sensitivity to low µM TMX in vitro and in vivo and also appear to be novel in enhancing sensitivity to a non‐canonical mode of action of an established therapeutic agent.
R5 HIV‐1 envelope attracts dendritic cells to cross the human intestinal epithelium and sample luminal virions via engagement of the CCR5
Authors: Cavarelli Mariangela , Foglieni Chiara , Rescigno Maria , Scarlatti Gabriella 
Published: April 2013

AbstractThe gastrointestinal tract is a principal route of entry and site of persistence of human immunodeficiency virus type 1 (HIV‐1). The intestinal mucosa, being rich of cells that are the main target of the virus, represents a primary site of viral replication and CD4+ T‐cell depletion. Here, we show both in vitro and ex vivo that HIV‐1 of R5 but not X4 phenotype is capable of selectively triggering dendritic cells (DCs) to migrate within 30 min between intestinal epithelial cells to sample virions and transfer infection to target cells. The engagement of the chemokine receptor 5 on DCs and the viral envelope, regardless of the genetic subtype, drive DC migration. Viruses penetrating through transient opening of the tight junctions likely create a paracellular gradient to attract DCs. The formation of junctions with epithelial cells may initiate a haptotactic process of DCs and at the same time favour cell‐to‐cell viral transmission. Our findings indicate that HIV‐1 translocation across the intestinal mucosa occurs through the selective engagement of DCs by R5 viruses, and may guide the design of new prevention strategies.→See accompanying article http://dx.doi.org/10.1002/emmm.201302763
Adaptive time series compensator for delay compensation of servo‐hydraulic actuator systems for real‐time hybrid simulation
Authors: Chae Yunbyeong , Kazemibidokhti Karim , Ricles James M. 
Published: April 2013

SUMMARYHydraulic actuators are typically used in a real‐time hybrid simulation to impose displacements to a test structure (also known as the experimental substructure). It is imperative that good actuator control is achieved in the real‐time hybrid simulation to minimize actuator delay that leads to incorrect simulation results. The inherent nonlinearity of an actuator as well as any nonlinear response of the experimental substructure can result in an amplitude‐dependent behavior of the servo‐hydraulic system, making it challenging to accurately control the actuator. To achieve improved control of a servo‐hydraulic system with nonlinearities, an adaptive actuator compensation scheme called the adaptive time series (ATS) compensator is developed. The ATS compensator continuously updates the coefficients of the system transfer function during a real‐time hybrid simulation using online real‐time linear regression analysis. Unlike most existing adaptive methods, the system identification procedure of the ATS compensator does not involve user‐defined adaptive gains. Through the online updating of the coefficients of the system transfer function, the ATS compensator can effectively account for the nonlinearity of the combined system, resulting in improved accuracy in actuator control. A comparison of the performance of the ATS compensator with existing linearized compensation methods shows superior results for the ATS compensator for cases involving actuator motions with predefined actuator displacement histories as well as real‐time hybrid simulations. Copyright © 2013 John Wiley & Sons, Ltd.
Alternative closed‐form solutions for the mean rate of exceedance of structural limit states
Authors: Romão Xavier , Delgado Raimundo , Costa Aníbal 
Published: April 2013

SUMMARYTwo new closed‐form expressions representing the mean rate of exceedance of a given limit state are presented herein. These proposals overcome limitations that were identified with the original formulation of the well‐known SAC/FEMA approach. The new expressions involve new parametric functions for the modeling of the seismic hazard data and for the demand evolution for increasing values of the earthquake intensity measure. Given the carefully selected parametric form of these functions, mathematical tractability is able to be maintained to establish two new closed‐form solutions representing the mean rate of exceedance of a given limit state. The function proposed for the hazard exhibits nonlinear behavior in log‐log space and is able to represent the actual hazard data over a wider range of earthquake intensity levels. The function proposed for the demand evolution addresses issues related to the inadequate performance of the SAC/FEMA approach when force‐based demand parameters such as the shear force are considered. To illustrate the applicability of the new closed‐form solutions, the probability of occurrence of several limit states is determined for a reinforced concrete structure. Copyright © 2013 John Wiley & Sons, Ltd.
Receiving while giving: The differential roles of receiving help and satisfaction with help on caregiver rewards among spouses and adult‐children
Authors: Savundranayagam Marie Y. 
Published: April 2013

ObjectiveThere is a growing body of literature on the rewards associated with caregiving and the utility of these rewards on buffering the negative consequences of caring for a family member with Alzheimer's disease. Many psychoeducational interventions aim to empower caregivers to seek and obtain help from their social support network, with the expectation that help will enable them to cope more effectively.MethodsThis study investigated the impact of changes in help and changes in satisfaction with help on positive aspects of caregiving for both spouse (N = 254) and adult‐child (N = 208) caregivers who attended a psychoeducational intervention.ResultsAnalyses using structural equation modeling revealed that increases in amount of help and satisfaction with help were significantly linked with increases in caregiver rewards for adult‐children. However, only increases in satisfaction with help were significantly related to increases in caregiver rewards for spouses.ConclusionsThese group differences suggest that the quality of support is critical for spouses, whereas both quality and receiving extra help are useful for adult‐child caregivers. These findings are discussed in terms of the importance of understanding the differential needs of spouse and adult‐child caregivers in practice. Copyright © 2013 John Wiley & Sons, Ltd.