bluuebunny/crossref_metadata_2025 huggingface dataset:
Atlas stumbled: Kinesin light chain‐1 variant E triggers a vicious cycle of axonal transport disruption and amyloid‐β generation in Alzheimer's disease
Authors: Gan Kathlyn J. , Morihara Takashi , Silverman Michael A.
Published: November 2014

Substantial evidence implicates fast axonal transport (FAT) defects in neurodegeneration. In Alzheimer's disease (AD), it is controversial whether transport defects cause or arise from amyloid‐β (Aβ)‐induced toxicity. Using a novel, unbiased genetic screen, Morihara et al. identified kinesin light chain‐1 splice variant E (KLC1vE) as a modifier of Aβ accumulation. Here, we propose three mechanisms to explain this causal role. First, KLC1vE reduces APP transport, leading to Aβ accumulation. Second, reduced transport of APP by KLC1vE triggers an ER stress response that activates the amyloidogenic pathway. Third, KLC1vE impairs transport of other KLC1 cargos that regulate amyloidogenesis, promoting Aβ retention within the secretory pathway. Collectively, KLC1vE perpetuates a vicious cycle of Aβ generation, kinase dysregulation, and global FAT impairment that inevitably leads to cellular toxicity. These concepts implicate alternative splicing of KLC1 in AD and suggest that the reciprocal influence of transport mechanisms on disease states contributes to neurodegeneration.
Inhibitors of Polyhydroxyalkanoate (PHA) Synthases: Synthesis, Molecular Docking, and Implications
Authors: Zhang Wei , Chen Chao , Cao Ruikai , Maurmann Leila , Li Ping
Published: November 2014

Polyhydroxyalkanoate (PHA) synthases (PhaCs) catalyze the formation of biodegradable PHAs that are considered to be ideal alternatives to non‐biodegradable synthetic plastics. However, study of PhaCs has been challenging because the rate of PHA chain elongation is much faster than that of initiation. This difficulty, along with lack of a crystal structure, has become the main hurdle to understanding and engineering PhaCs for economical PHA production. Here we report the synthesis of two carbadethia CoA analogues—sT‐CH2‐CoA (26 a) and sTet‐CH2‐CoA (26 b)—as well as sT‐aldehyde (saturated trimer aldehyde, 29), as new PhaC inhibitors. Study of these analogues with PhaECAv revealed that 26 a/b and 29 are competitive and mixed inhibitors, respectively. Both the CoA moiety and extension of PHA chain will increase binding affinity; this is consistent with our docking study. Estimation of the Kic values of 26 a and 26 b predicts that a CoA analogue incorporating an octameric hydroxybutanoate (HB) chain might facilitate the formation of a kinetically well‐behaved synthase.
A Regioselective Synthesis of Benzopinacolones through Aerobic Dehydrogenative α‐Arylation of the Tertiary sp3 CH Bond of 1,1‐Diphenylketones with Aromatic and Heteroaromatic Compounds
Authors: More Nagnath Yadav , Jeganmohan Masilamani
Published: November 2014

A regioselective synthesis of symmetrical and unsymmetrical benzopinacolones through aerobic dehydrogenative α‐arylation at the tertiary sp3 CH bond of substituted 1,1‐diphenylketones with aromatic and heteroaromatic compounds, in the presence of K2S2O8 in CF3COOH at room temperature, is described. The reaction is proposed to go via a carbocation intermediate, which could be generated directly from cleavage of the sp3 CH bond of 1,1‐diphenylketone. Subsequent α‐arylation was achieved at the methene sp3 carbon atom of the substituted ketone. A variety of substituted aromatic and heteroaromatic compounds were compatible with this reaction. In addition, benzopinacolones were converted into sterically hindered, tetrasubstituted alkenes and polycyclic aromatic compounds.
A Heteroleptic Push–Pull Substituted Iron(II) Bis(tridentate) Complex with Low‐Energy Charge‐Transfer States
Authors: Mengel Andreas K. C. , Förster Christoph , Breivogel Aaron , Mack Katharina , Ochsmann Julian R. , Laquai Frédéric , Ksenofontov Vadim , Heinze Katja
Published: November 2014

A heteroleptic iron(II) complex [Fe(dcpp)(ddpd)]2+ with a strongly electron‐withdrawing ligand (dcpp, 2,6‐bis(2‐carboxypyridyl)pyridine) and a strongly electron‐donating tridentate tripyridine ligand (ddpd, N,N′‐dimethyl‐N,N′‐dipyridine‐2‐yl‐pyridine‐2,6‐diamine) is reported. Both ligands form six‐membered chelate rings with the iron center, inducing a strong ligand field. This results in a high‐energy, high‐spin state (5T2, (t2g)4(eg*)2) and a low‐spin ground state (1A1, (t2g)6(eg*)0). The intermediate triplet spin state (3T1, (t2g)5(eg*)1) is suggested to be between these states on the basis of the rapid dynamics after photoexcitation. The low‐energy π* orbitals of dcpp allow low‐energy MLCT absorption plus additional low‐energy LL′CT absorptions from ddpd to dcpp. The directional charge‐transfer character is probed by electrochemical and optical analyses, Mößbauer spectroscopy, and EPR spectroscopy of the adjacent redox states [Fe(dcpp)(ddpd)]3+ and [Fe(dcpp)(ddpd)]+, augmented by density functional calculations. The combined effect of push–pull substitution and the strong ligand field paves the way for long‐lived charge‐transfer states in iron(II) complexes.
Multiple‐Stimulus‐Responsive Supramolecular Gels of Two Components and Dual Chiroptical Switches
Authors: Miao Wangen , Qin Long , Yang Dong , Jin Xue , Liu Minghua
Published: November 2014

A new class of L‐glutamic gelators, LG12(CH2)nCOOH, containing different lengths of methylene spacer were synthesized. It was found that the gelation ability of these compounds themselves was very weak. However, when another compound, p‐xylylenediamine (XEA), was introduced, the gelation ability was improved greatly. In particular, LG12(CH2)10COOH showed super‐gelation ability in the presence of XEA, which could immobilize almost all of the solvents except methanol. Moreover, the formed supramolecular gels even could be molded. Interestingly, some supramolecular gels of LG12(CH2)nCOOH and XEA could respond to multiple stimuli, such as heating, shaking, sonication, and acid/base. The studies of CD spectra suggested that the supramolecular chirality induced by self‐assembled chiral gelator molecules in gels could be tuned by the length of methylene spacer. In addition, the supramolecular chirality could be regulated as on/off by heating–cooling or external NH3/HCl. This would facilitate the development of dual chiroptical switches by temperature and acid/base.
Stable but Reactive Perfluoroalkylzinc Reagents: Application in Ligand‐Free Copper‐Catalyzed Perfluoroalkylation of Aryl Iodides
Authors: Aikawa Kohsuke , Nakamura Yuzo , Yokota Yuki , Toya Wataru , Mikami Koichi
Published: November 2014

The aromatic perfluoroalkylation catalyzed by a copper(I) salt with bis(perfluoroalkyl)zinc reagents Zn(RF)2(DMPU)2, which were prepared and then isolated as a stable white powder from perfluoroalkyl iodide and diethylzinc, was accomplished to provide the perfluoroalkylated products in good‐to‐excellent yields. The advantages of this reliable and practical catalytic reaction are 1) air‐stable and easy‐to‐handle bis(perfluoroalkyl)zinc reagents can be utilized, 2) the reagent is reactive and hence the operation without activators and ligands is simple, and 3) not only trifluoromethylation but also perfluoroalkylation can be attained.
ChemInform Abstract: Principles and Mechanisms of Photocatalytic Dye Degradation on TiO2 Based Photocatalysts: A Comparative Overview
Authors: Ajmal Anila , Majeed Imran , Malik Riffat Naseem , Idriss Hicham , Nadeem Muhammad Amtiaz
Published: November 2014

Review: 371 refs.
Fluidized‐Bed Reactors – Status and Some Development Perspectives
Authors: Werther Joachim , Hartge Ernst‐Ulrich , Heinrich Stefan
Published: November 2014

This review of industrial applications of fluidized‐bed reactors is focused on the fluid catalytic cracking (FCC) process and the fluidized‐bed combustion. Both processes have a tremendous economic importance. In the FCC process, the main challenges are the increase of runtime, the adaption of the product spectrum to regional requirements of the market, and the adaption to heavier feedstocks. In fluidized‐bed combustion the main trends are towards larger units sizes, higher efficiency, and further reduced emissions while keeping the boiler as flexible as possible with regard to the mixture of fuels.
A systematic review of diastolic stress tests in heart failure with preserved ejection fraction, with proposals from the EU‐FP7 MEDIA study group
Authors: Erdei Tamás , Smiseth Otto A. , Marino Paolo , Fraser Alan G.
Published: November 2014

Aims

Cardiac function should be assessed during stress in patients with suspected heart failure with preserved ejection fraction (HFPEF), but it is unclear how to define impaired diastolic reserve.

Methods and results

We conducted a systematic review to identify which pathophysiological changes serve as appropriate targets for diagnostic imaging. We identified 38 studies of 1111 patients with HFPEF (mean age 65 years), 744 control patients without HFPEF, and 458 healthy subjects. Qualifying EF was >45–55%; diastolic dysfunction at rest was a required criterion in 45% of studies. The initial workload during bicycle exercise (25 studies) varied from 12.5 to 30 W (mean 23.1 ± 4.6), with increments of 10–25 W (mean 19.9 ± 6) and stage duration 1–5 min (mean 2.5 ± 1); targets were submaximal (n = 8) or maximal (n = 17). Other protocols used treadmill exercise, handgrip, dobutamine, lower body negative pressure, nitroprusside, fluid challenge, leg raising, or atrial pacing. Reproducibility of echocardiographic variables during stress and validation against independent reference criteria were assessed in few studies. Change in E/e' was the most frequent measurement, but there is insufficient evidence to establish this or other tests for routine use when evaluating patients with HFPEF.

Conclusions

To meet the clinical requirements of performing stress testing in elderly subjects, we propose a ramped exercise protocol on a semi‐supine bicycle, starting at 15 W, with increments of 5 W/min to a submaximal target (heart rate 100–110 b.p.m., or symptoms). Measurements during submaximal and recovery stages should include changes from baseline in LV long‐axis function and indirect echocardiographic indices of LV diastolic pressure.
Highly Stable Complexes of Divalent Metal Ions (Mg2+, Ca2+, Cu2+, Zn2+, Cd2+, and Pb2+) with a Dota‐Like Ligand Containing a Picolinate Pendant
Authors: Regueiro‐Figueroa Martín , Ruscsák Erika , Fra Laura , Tircsó Gyula , Tóth Imre , de Blas Andrés , Rodríguez‐Blas Teresa , Platas‐Iglesias Carlos , Esteban‐Gómez David
Published: November 2014

The stability constants of complexes of the macrocyclic ligand do3a‐pic4– (H4do3a‐pic = 2,2′,2″‐{10‐[(6‐carboxypyridin‐2‐yl)methyl]‐1,4,7,10‐tetraazacyclododecane‐1,4,7‐triyl}triacetic acid) with several divalent metal ions (Pb2+, Cd2+, Zn2+, Cu2+, Ca2+, and Mg2+) have been determined by using pH‐potentiometric titrations (I = 0.1 M KCl, 25 °C). The stability of these complexes follows the trend Cu2+ > Cd2+ ≈ Pb2+ ≈ Zn2+ >> Ca2+ >> Mg2+. A particularly high stability constant has been determined for the Cu2+ complex [log KCuL = 23.20(4)]. Analysis of the titration curves indicate the presence of protonated forms of the complexes in solution, with protonation constants of log KM(HxL) = 6.9–2.0 (x = 1, 2, or 3). The structure of the complexes in solution has been investigated by using 1H and 13C NMR spectroscopy and DFT calculations performed in aqueous solution at the TPSSh/6‐31G(d) level. In the case of the Pb2+ and Cd2+ complexes, relativistic effects were considered with the use of relativistic effective core potentials. Calculations show that the complexes with the largest metal ions (Pb2+ and Ca2+) are nine‐coordinate, with their coordination polyhedra being best described as capped twisted square antiprisms. The Cd2+ and Mg2+ complexes are seven‐coordinate, with the metal ions being bound to the four nitrogen atoms of the cyclen unit and the three acetate pendant arms. Finally, in the Cu2+ and Zn2+ complexes, the metal ions are six‐coordinated, with the metal ions being asymmetrically placed inside the macrocyclic cavity of the ligand, and the coordination polyhedra can be described as an octahedron and a trigonal prism, respectively.
Facile Synthesis of Cyclohexanediones and Dialkylresorcinols – Bioactive Natural Products from Entomopathogenic Bacteria
Authors: Kronenwerth Max , Dauth Christina , Kaiser Marcel , Pemberton Iain , Bode Helge B.
Published: November 2014

A synthesis for the recently identified, widespread bacterial natural product classes of dialkylresorcinols and cyclohexanediones was developed. The synthesis route is similar to the biosynthesis route in that the formation of the cyclohexanedione ring results from two parts, as exemplified by the synthesis of the multifunctional isopropylstilbenes identified in Photorhabdus luminescens. Testing of these compounds revealed good bioactivity against Trypanosoma brucei rhodesiense and T. cruzi, the causative agents of sleeping sickness and Chagas disease, respectively.
Screen‐Printed Electrochemical 96‐Well Plate: a High‐Throughput Platform for Multiple Analytical Applications
Authors: Neves M. M. P. S. , González‐García M. B. , Hernández‐Santos D. , Fanjul‐Bolado P.
Published: November 2014

A new screen‐printed electrochemical array formed by 96 three‐electrode electrochemical cells with carbon‐based working electrodes (DRP‐96X110) was developed by DropSens. The electrochemical and electro(analytical) performance of this multiple‐analysis plate is herein presented. Different proofs of concept relying on reference benchmark redox compounds, streptavidin‐biotin high affinity interactions and magnetic‐based immunoassays were carried out. The results showed the electrochemical plate versatility and usefulness as an innovative high‐throughput transducer surface for multiple and decentralized applications.
Impedance Spectroscopic Characterisation of Porosity in 3D Cell Culture Scaffolds with Different Channel Networks
Authors: Canali Chiara , Mohanty Soumyaranjan , Heiskanen Arto , Muhammad Haseena Bashir , Martinsen Ørjan Grøttem , Dufva Martin , Wolff Anders , Emnéus Jenny
Published: November 2014

We present the application of electrochemical impedance spectroscopy (EIS) as a method for discriminating between different polydimethylsiloxane (PDMS) scaffolds for three‐dimensional (3D) cell cultures. The validity of EIS characterisation for scaffolds having different degree of porosity (networks of structured or random channels) is discussed in relation to Archie’s law. Guidelines for EIS analysis are presented and demonstrated to provide porosity information in physiological buffer that agrees well with a more conventional weight‐based approach. We also propose frequency ranges that may serve as means of single‐frequency measurements for fast scaffold characterization combined with in vitro monitoring of 3D cell cultures.
Trends in Unconventional Well Development—Methane Emissions Associated with the Use of Dual Fuel and Dedicated Natural Gas Engines
Authors: Johnson Derek , Heltzel Robert , Nix Andrew
Published: November 2014

The process of unconventional natural gas recovery is becoming increasingly popular as the world’s demand for alternative fuels continues to grow. Natural gas has the potential to be a widely used fuel in the near future due to its availability and potential to displace petroleum‐based liquid fuels. As energy companies extract natural gas, current fuels, such as diesel, are consumed in mass quantities for drilling and hydraulic fracturing operations. To save on costs, and in an attempt to reduce emissions, many companies are investing in dual fuel and dedicated natural gas engines to power these operations. This trend results in new sources of methane emissions, which can contribute significantly to global warming. We are aware of the potential impact of these emissions and are conducting research funded by the Department of Energy to assess methane emissions from dual fuel and dedicated natural gas technologies, as industry moves towards more extensive use of natural gas as a fuel for onsite power production.
Adjoint‐based airfoil optimization with discretization error control
Authors: Li D. , Hartmann R.
Published: November 2014

In this article, we develop a new airfoil shape optimization algorithm based on higher‐order adaptive DG methods with control of the discretization error. Each flow solution in the optimization loop is computed on a sequence of goal‐oriented h‐refined or hp‐refined meshes until the error estimation of the discretization error in a flow‐related target quantity (including the drag and lift coefficients) is below a prescribed tolerance. Discrete adjoint solutions are computed and employed for the multi‐target error estimation and adaptive mesh refinement. Furthermore, discrete adjoint solutions are employed for evaluating the gradients of the objective function used in the CGs optimization algorithm. Furthermore, an extension of the adjoint‐based gradient evaluation to the case of target lift flow computations is employed. The proposed algorithm is demonstrated on an inviscid transonic flow around the RAE2822, where the shape is optimized to minimize the drag at a given constant lift and airfoil thickness. The effect of the accuracy of the underlying flow solutions on the quality of the optimized airfoil shapes is investigated. Copyright © 2014 John Wiley & Sons, Ltd.
Heuristic Identification of Biological Architectures for Simulating Complex Hierarchical Genetic Interactions
Authors: Moore Jason H. , Amos Ryan , Kiralis Jeff , Andrews Peter C.
Published: November 2014

Simulation plays an essential role in the development of new computational and statistical methods for the genetic analysis of complex traits. Most simulations start with a statistical model using methods such as linear or logistic regression that specify the relationship between genotype and phenotype. This is appealing due to its simplicity and because these statistical methods are commonly used in genetic analysis. It is our working hypothesis that simulations need to move beyond simple statistical models to more realistically represent the biological complexity of genetic architecture. The goal of the present study was to develop a prototype genotype–phenotype simulation method and software that are capable of simulating complex genetic effects within the context of a hierarchical biology‐based framework. Specifically, our goal is to simulate multilocus epistasis or gene–gene interaction where the genetic variants are organized within the framework of one or more genes, their regulatory regions and other regulatory loci. We introduce here the Heuristic Identification of Biological Architectures for simulating Complex Hierarchical Interactions (HIBACHI) method and prototype software for simulating data in this manner. This approach combines a biological hierarchy, a flexible mathematical framework, a liability threshold model for defining disease endpoints, and a heuristic search strategy for identifying high‐order epistatic models of disease susceptibility. We provide several simulation examples using genetic models exhibiting independent main effects and three‐way epistatic effects.
A depressive endophenotype of poorer cognition among cognitively healthy community‐dwelling adults: results from the Western Australia memory study
Authors: Johnson Leigh A. , Sohrabi Hamid R. , Hall James R. , Kevin Taddei , Edwards Melissa , O'Bryant Sid E. , Martins Ralph N.
Published: November 2014

Objective

The objective was to evaluate in a cognitively normal population the utility of an endophenotype of the depression–cognition link previously shown to be related to cognitive functioning in mild cognitive impairment and Alzheimer's disease.

Methods

The data of 460 cognitively normal adults aged 32–92 years (M = 63.5, standard deviation = 9.24) from the Western Australian Memory Study with the Cross‐national comparisons of the Cambridge Cognitive Examination‐revised (CAMCOG‐R) scores and 30‐item Geriatric Depression Scale (GDS) scores were analyzed to determine the relationship between the five‐item depressive endophenotype (DepE) scale drawn from the GDS and level of performance on a measure of cognitive functioning.

Results

For the entire sample, there was a nonsignificant trend toward a negative relationship between DepE and CAMCOG‐R scores. When analyzed for those 65 years and older, there was a significant negative relationship between the two measures (p = 0.001) with DepE scores significantly increasing the risk for performing more poorly on the CAMCOG‐R (odds ratio = 1.53). Analysis of data for those 70 years and older showed that DepE was the only predictor significantly related to poorer CAMCOG‐R performance (p = 0.001). For the 70 years and older group, DepE scores significantly increased the risk of poorer CAMCOG‐R scores (odds ratio = 2.23). Analysis of the entire sample on the basis of ApoEε4 carrier status revealed that DepE scores were significantly negatively related only to ApoEε4 noncarrier regardless of age.

Conclusions

Elevated DepE scores are associated with poor neuropsychological performance among cognitively normal older adults. Use of the DepE may allow for the identification of a subset of older adults where depression is a primary factor in cognitive decline and who may benefit from antidepressant therapies. Copyright © 2014 John Wiley & Sons, Ltd.
Frontopolar activity and connectivity support dynamic conscious augmentation of creative state
Authors: Green Adam E. , Cohen Michael S. , Raab Hillary A. , Yedibalian Christopher G. , Gray Jeremy R.
Published: November 2014

No ability is more valued in the modern innovation‐fueled economy than thinking creatively on demand, and the “thinking cap” capacity to augment state creativity (i.e., to try and succeed at thinking more creatively) is of broad importance for education and a rich mental life. Although brain‐based creativity research has focused on static individual differences in trait creativity, less is known about changes in creative state within an individual. How does the brain augment state creativity when creative thinking is required? Can augmented creative state be consciously engaged and disengaged dynamically across time? Using a novel “thin slice” creativity paradigm in 55 fMRI participants performing verb‐generation, we successfully cued large, conscious, short‐duration increases in state creativity, indexed quantitatively by a measure of semantic distance derived via latent semantic analysis. A region of left frontopolar cortex, previously associated with creative integration of semantic information, exhibited increased activity and functional connectivity to anterior cingulate gyrus and right frontopolar cortex during cued augmentation of state creativity. Individual differences in the extent of increased activity in this region predicted individual differences in the extent to which participants were able to successfully augment state creative performance after accounting for trait creativity and intelligence. Hum Brain Mapp 36:923–934, 2015. © 2014 Wiley Periodicals, Inc.
Does Physician Dispensing Increase Drug Expenditures? Empirical Evidence from Switzerland
Authors: Kaiser Boris , Schmid Christian
Published: November 2014

This paper analyzes whether the opportunity for physicians to dispense drugs increases healthcare expenditures. We study the case of Switzerland, where dispensing physicians face financial incentives to overprescribe and sell more expensive pharmaceuticals. Using comprehensive physician‐level data, we exploit the regional variation in the dispensing regime to estimate causal effects. The empirical strategy consists of a doubly‐robust estimation that combines inverse probability weighting with regression. Our main finding suggests that dispensing leads to higher drug costs on the order of 34% per patient. Copyright © 2014 John Wiley & Sons, Ltd.
Hybrid MPI/OpenMP parallelization of the effective fragment potential method in the libefp software library
Authors: Kaliman Ilya A. , Slipchenko Lyudmila V.
Published: November 2014

A new hybrid MPI/OpenMP parallelization scheme is introduced for the Effective Fragment Potential (EFP) method implemented in the libefp software library. The new implementation employs dynamic load balancing algorithm that uses a master/slave model. The software shows excellent parallel scaling up to several hundreds of CPU‐cores across multiple nodes. The code uses functions only from the well‐established MPI‐1 standard that simplifies portability of the library. This new parallel EFP implementation greatly expands the applicability of the EFP and QM/EFP methods by extending attainable time‐ and length‐scales. © 2014 Wiley Periodicals, Inc.
Linear‐scaling self‐consistent field calculations based on divide‐and‐conquer method using resolution‐of‐identity approximation on graphical processing units
Authors: Yoshikawa Takeshi , Nakai Hiromi
Published: November 2014

Graphical processing units (GPUs) are emerging in computational chemistry to include Hartree−Fock (HF) methods and electron‐correlation theories. However, ab initio calculations of large molecules face technical difficulties such as slow memory access between central processing unit and GPU and other shortfalls of GPU memory. The divide‐and‐conquer (DC) method, which is a linear‐scaling scheme that divides a total system into several fragments, could avoid these bottlenecks by separately solving local equations in individual fragments. In addition, the resolution‐of‐the‐identity (RI) approximation enables an effective reduction in computational cost with respect to the GPU memory. The present study implemented the DC‐RI‐HF code on GPUs using math libraries, which guarantee compatibility with future development of the GPU architecture. Numerical applications confirmed that the present code using GPUs significantly accelerated the HF calculations while maintaining accuracy. © 2014 Wiley Periodicals, Inc.
A 49 year hindcast of surface winds over the Iberian Peninsula
Authors: Lorente‐Plazas R. , Montávez J. P. , Jerez S. , Gómez‐Navarro J. J. , Jiménez‐Guerrero P. , Jiménez P. A.
Published: November 2014

The use of hindcast climatic data is quite extended for multiple applications. However, this approach needs the support of a validation process to allow its drawbacks and, therefore, confidence levels to be assessed. In this work, the strategy relies on an hourly wind database resulting from a dynamical downscaling experiment, with a spatial resolution of 10 km, covering the Iberian Peninsula (IP), driven by the ERA40 reanalysis (1959–2001) extended by European Centre for Medium‐Range Weather Forecast (ECMWF) analysis (2002–2007) and comprising two main steps.

Initially, the skill of the simulation is evaluated comparing the quality‐tested observational database (Lorente‐Plazas et al., 2014) at local and regional scales. The results show that the model is able to portray the main features of the wind over the IP: annual cycles, wind roses, spatial and temporal variability, as well as the response to different circulation types. In addition, there is a significant added value of the simulation with respect to driving conditions, especially in regions with a complex orography. However, some problems are evident, the major drawback being the systematic overestimation of the wind speed, which is mainly attributed to a missrepresentation of frictional forces. The model skill is also lower along the Mediterranean coast and for the Pyrenees.

In a second phase, the high spatio‐temporal resolution of the pseudo‐real wind database is used to explore the limitations of the observational database. It is shown that missing values do not affect the characterisation of the wind climate over the IP, while the length of the observational period (6 years) is sufficient for most regions, with only a few exceptions. The spatial distribution of the observational sampling schemes should be enhanced to improve the correct assessment of all IP wind regimes, particularly in some mountainous areas.
Inter‐decadal variability in potential glacier surface melt energy at Vestari Hagafellsjökull (Langjökull, Iceland) and the role of synoptic circulation
Authors: Matthews T. , Hodgkins R. , Guðmundsson S. , Pálsson F. , Björnsson H.
Published: November 2014

The surface energy balance (SEB) of glaciers, although of considerable importance for understanding the melt response to climate change, is rarely analysed for more than a few melt seasons due to the logistical challenges of meteorological measurement campaigns on glaciers. Insight into low‐frequency (inter‐decadal) changes in the SEB in response to climate warming and variable atmospheric circulation patterns has thus been limited. Here this problem is addressed by using ERA‐Interim reanalysis data to extend glacier‐meteorological records at two locations on Vestari Hagafellsjökull (Iceland) for the period 1979–2012. Trend analysis is conducted for this series before the role of synoptic circulation in modulating surface energetics is investigated. The results indicate that potential melt energy has increased significantly throughout the period of simulation at both locations (by 19.7 and 32.4%), with the largest increase evident for the turbulent heat fluxes (36.3 and 93.1%). The synoptic conditions associated with the recent high melt rates on the proximate Greenland Ice Sheet (GrIS) do not result in similarly extreme melt conditions for our Icelandic location. We also find that the North Atlantic Oscillation Index is significantly correlated with the radiative and latent heat components of the SEB. This association remains hidden if the melt rate is assessed in isolation, highlighting the utility of the SEB approach presented here for assessing synoptic aspects of glacier‐climate interactions.
Tropical cyclone activity over Madagascar during the late nineteenth century
Authors: Nash David J. , Pribyl Kathleen , Klein Jørgen , Endfield Georgina H. , Kniveton Dominic R. , Adamson George C. D.
Published: November 2014

Tropical cyclones (TCs) represent the most significant natural hazard for the economy and population of Madagascar. Planning for the impacts of future cyclone strikes requires a detailed understanding of the frequency of destructive storms in the past. In this paper, we utilise historical documentary materials to construct an initial framework of TCs making landfall on Madagascar during the latter half of the 19th century. The study focuses on 1862–1900 as this is the period of most extensive documentary records. Accounts of storm damage contained within historical sources are used to reconstruct TC tracks over land, with details of wind damage converted into Fujita (F) Scale classes to classify TC intensity. A total of 20 TCs are identified, of which only 17 are included within the IBTrACS dataset for the southwest Indian Ocean. The TCs of 13–14 March 1872 and 28 January–1 February 1893 were the most destructive of the late 19th century, with F3+ levels of wind damage identified from historical accounts. We compare our results with data for TCs within the IBTrACS dataset that made landfall on Madagascar during the period 1970–2012. This comparison suggests that (1) fewer TCs made landfall during the 19th century compared with the post‐satellite era, but that of these (2) a greater proportion appear to have crossed the northeast of the island. There is no significant correlation between numbers of landfalling TCs and either mean annual SOI or DMI. We conclude with a consideration of additional archival collections that may be used in future investigations to enhance our chronology.
In vivo proton MR spectroscopy of pancreatic neuroendocrine tumors in a multiple endocrine neoplasia type 1 conditional knockout mouse model
Authors: Cui Min‐Hui , Branch Craig A. , Cahill Sean M. , Quinn Thomas J. , Adem Asha , Libutti Steven K. , Yuan Ziqiang
Published: November 2014

Purpose

MR spectroscopy (MRS) can improve diagnosis and follow treatment in cancer. However, no study has yet reported application of in vivo 1H‐MRS in malignant pancreatic lesions. This study quantitatively determined whether in vivo 1H‐MRS on multiple endocrine neoplasia type 1 (Men1) conditional knockout (KO) mice and their wild type (WT) littermates could detect differences in total choline (tCho) levels between tumor and control pancreas.

Methods

Relative tCho levels in pancreatic tumors or pancreata from KO and WT mice were determined using in vivo 1H‐MRS at 9.4 T. The levels of Cho‐containing compounds were also quantified using in vitro 1H‐NMR on extracts of pancreatic tissues from KO and WT mice, respectively, and on extracts of pancreatic tissues from patients with pancreatic neuroendocrine tumors (PNETs).

Results

tCho levels measured by in vivo 1H‐MRS were significantly higher in PNETs from KO mice compared to the normal pancreas from WT mice. The elevated choline‐containing compounds were also identified in pancreatic tumors from KO mice and tissues from patients with PNETs via in vitro 1H‐NMR.

Conclusion

These results indicate the potential use of tCho levels estimated via in vivo 1H‐MRS in differentiating malignant pancreatic tumors from benign tumors. Magn Reson Med 74:1221–1226, 2015. © 2014 Wiley Periodicals, Inc.
1H MRS characterization of neurochemical profiles in orthotopic mouse models of human brain tumors
Authors: Hulsey Keith M. , Mashimo Tomoyuki , Banerjee Abhishek , Soesbe Todd C. , Spence Jeffrey S. , Vemireddy Vamsidhara , Maher Elizabeth A. , Bachoo Robert M. , Choi Changho
Published: November 2014

Glioblastoma (GBM), the most common primary brain tumor, is resistant to currently available treatments. The development of mouse models of human GBM has provided a tool for studying mechanisms involved in tumor initiation and growth as well as a platform for preclinical investigation of new drugs. In this study we used 1H MR spectroscopy to study the neurochemical profile of a human orthotopic tumor (HOT) mouse model of human GBM. The goal of this study was to evaluate differences in metabolite concentrations in the GBM HOT mice when compared with normal mouse brain in order to determine if MRS could reliably differentiate tumor from normal brain. A TE =19 ms PRESS sequence at 9.4 T was used for measuring metabolite levels in 12 GBM mice and 8 healthy mice. Levels for 12 metabolites and for lipids/macromolecules at 0.9 ppm and at 1.3 ppm were reliably detected in all mouse spectra. The tumors had significantly lower concentrations of total creatine, GABA, glutamate, total N‐acetylaspartate, aspartate, lipids/macromolecules at 0.9 ppm, and lipids/macromolecules at 1.3 ppm than did the brains of normal mice. The concentrations of glycine and lactate, however, were significantly higher in tumors than in normal brain. Copyright © 2014 John Wiley & Sons, Ltd.
A new look at the doubling algorithm for a structured palindromic quadratic eigenvalue problem
Authors: Lu Linzhang , Yuan Fei , Li Ren‐Cang
Published: November 2014

Recently, Guo and Lin [SIAM J. Matrix Anal. Appl., 31 (2010), 2784–2801] proposed an efficient numerical method to solve the palindromic quadratic eigenvalue problem (PQEP) (λ2AT+λQ + A)z = 0 arising from the vibration analysis of high speed trains, where have special structures: both Q and A are, among others, m × m block matrices with each block being k × k (thus, n = mk), and moreover, Q is block tridiagonal, and A has only one nonzero block in the (1,m)th block position. The key intermediate step of the method is the computation of the so‐called stabilizing solution to the n × n nonlinear matrix equation X + ATX−1A = Q via the doubling algorithm. The aim of this article is to propose an improvement to this key step through solving a new nonlinear matrix equation having the same form but of only k × k in size. This new and much smaller matrix equation can also be solved by the doubling algorithm. For the same accuracy, it takes the same number of doubling iterations to solve both the larger and the new smaller matrix equations, but each doubling iterative step on the larger equation takes about 4.8 as many flops than the step on the smaller equation. Replacing Guo's and Lin's key intermediate step by our modified one leads to an alternative method for the PQEP. This alternative method is faster, but the improvement in speed is not as dramatic as just for solving the respective nonlinear matrix equations and levels off as m increases. Numerical examples are presented to show the effectiveness of the new method. Copyright © 2014 John Wiley & Sons, Ltd.
MALTREATMENT, ACADEMIC DIFFICULTY, AND SYSTEMS‐INVOLVED YOUTH: CURRENT EVIDENCE AND OPPORTUNITIES
Authors: Stone Susan , Zibulsky Jamie
Published: November 2014

Youth involved in child‐serving systems of care (e.g., child welfare and juvenile justice) often exhibit specific academic performance problems. The magnitude of academic risk among these students is a serious concern given that school attachment, performance, and attainment closely relate to indicators of well‐being across the lifespan. It is also important to consider that the experience of maltreatment is linked to both academic difficulty and formal system involvement. This paper highlights recent research focused on the academic performance of children and adolescents involved with child welfare and juvenile justice systems, with specific emphasis on highlighting prevention and intervention strategies that cut across systems. To meet the complex needs of these populations, school psychologists and other support staff should be cognizant of students’ academic needs and take a leadership role in collaborating within and across systems to meet them.
Enhanced electrical and mechanical properties of nanographite electrodes for supercapacitors by addition of nanofibrillated cellulose
Authors: Andres Britta , Forsberg Sven , Dahlström Christina , Blomquist Nicklas , Olin Håkan
Published: November 2014

Graphene and porous carbon materials are widely used as electrodes in supercapacitors. In order to form mechanically stable electrodes, binders can be added to the conducting electrode material. However, most binders degrade the electrical performance of the electrodes. Here we show that by using nanofibrillated cellulose (NFC) as a binder the electrical properties, such as capacitance, were enhanced. The highest capacitance was measured at an NFC content of approximately 10 % in ratio to the total amount of active material. The NFC improved the ion transport in the electrodes. Thus, electrodes made of a mixture of nanographite and NFC achieved larger capacitances in supercapacitors than electrodes with nanographite only. In addition to electrical properties, NFC enhanced the mechanical stability and wet strength of the electrodes significantly. Furthermore, NFC stabilized the aqueous nanographite dispersions, which improved the processability. Galvanostatic cycling was performed and an initial transient behaviour of the supercapacitors during the first cycles was observed. However, stabilized supercapacitors showed efficiencies of 98–100%.
EPR, ESE, and pulsed ENDOR study of the nitrogen donors in 15R SiC grown under carbon‐rich conditions
Authors: Savchenko Dariya , Kalabukhova Ekaterina , Shanina Bela , Pöppl Andreas , Yukhymchuk Volodymyr , Lančok Jan , Ubyivovk Evgenii , Mokhov Evgenii
Published: November 2014

X‐band field‐sweep electron spin echo and pulsed electron nuclear double resonance (ENDOR) spectroscopy were used to study n‐type 15R SiC wafers grown under carbon (C)‐rich conditions with the aim to verify the recently proposed concept that nitrogen (N) donors substitute both carbon (C) and silicon (Si) sites and may occupy nonequivalent positions at Si sites. It was found that besides the 14N ENDOR spectra of the C substituting quasicubic “k1”, “k2”, and “k3” positions five doublet lines due to 14N nuclei at other lattice positions were observed in the ENDOR spectrum of highly compensated C‐rich n‐type 15R SiC. Three of them with the hyperfine interaction (HFI) constants 34.66, 32.20, and 29.77 MHz were attributed to the N donors substituting “k1”, “k2”, and “k3” positions at Si sites. Two other additional ENDOR spectra were explained by the presence of the C antisite (CSi) defects in C‐rich 15R SiC, which leads to the formation of CSiNC complexes with donor levels close to the conduction‐band minimum and isotropic 14N HFI constants of 21.58 and 25.94 MHz. The energy levels of N donors have been evaluated by comparing the number of ENDOR spectra observed in C‐rich 15R SiC with different degrees of compensation.
Design, Development, and Mobility Evaluation of an Omnidirectional Mobile Robot for Rough Terrain
Authors: Ishigami Genya , Iagnemma Karl , Overholt Jim , Hudas Greg
Published: November 2014

Omnidirectional vehicles have been widely applied in several areas, but most of them are designed for the case of motion on flat, smooth terrain, and are not feasible for outdoor usage. This paper presents the design and development of an omnidirectional mobile robot that possesses high mobility in rough terrain. The omnidirectional robot consists of a main body with four sets of mobility modules, called an active split offset caster (ASOC). The ASOC module has independently driven dual wheels that produce arbitrary planar translational velocity, enabling the robot to achieve its omnidirectional motion. Each module is connected to the main body via a parallel link with shock absorbers, allowing the robot to conform to uneven terrain. In this paper, the design and development of the ASOC‐driven omnidirectional mobile robot for rough terrain are described. A control scheme that considers the kinematics of the omnidirectional mobile robot is presented. The mobility of the robot is also evaluated experimentally based on a metric called the ASOC mobility index. The mobility evaluation test clarifies a design tradeoff between terrain adaptability and omnidirectional mobility due to the shock absorbers. In addition, an odometry improvement technique that can reduce position estimation error due to wheel slippage is proposed. Experimental odometry tests confirmed that the proposed technique is able to improve the odometry accuracy for sharp‐turning maneuvers.
Ionic Ferrocenyl Compounds Containing Polycyano Anions. Synthesis, Structures, and Effects on Thermal Decomposition of Core Components of Solid Propellants
Authors: Gao Xiaoni , Li Jizhen , Luo Yang , Li Chunxiao , Bi Fuqiang , Zhang Weiqiang , Zhang Guofang , Gao Ziwei
Published: November 2014

For lowering high migration tendency of alkyl‐substituted ferrocenes as burning‐rate catalysts in composite solid propellants, eight new ionic ferrocenyl compounds, [FcCH2N(CH3)2(CnH2n+1]+X– (Fc = ferrocenyl; X– = 1,1,3,3‐tetracyanopropenide; n = 3–10; consequently numbered as 1–8), were synthesized and characterized by 1H NMR, 13C NMR, FT‐IR and UV/Vis spectroscopy as well as elementary analysis. In addition, the structures of 1, 3, and 5 were confirmed by single‐crystal X‐ray diffraction analysis and their cations were studied by density functional theory calculations (DFT). 1, 3, and 5 crystallize in the triclinic space group P$\bar{1}$. 1–6 show highly thermal stability (>166 °C), whereas compounds 7 and 8 exhibit volatility to a certain degree. Cyclic voltammetry studies suggested that each salt exhibits a quasi‐reversible redox wave of the ferrocenyl group. The effects of the new compounds on thermal decomposition of ammonium perchlorate (AP), 1,3,5‐trinitro‐1,3,5‐triazacyclohexane (RDX), and 1,2,5,7‐tetranitro‐1,3,5,7‐tetraazacyclooctane (HMX) were investigated by DSC technique. The results show that all the new compounds can catalyze thermal degradation of AP and RDX effectively and are higher in catalytic activity than the corresponding nitrates and picrates, verifying the prospect that relatively high nitrogen content in an ionic ferrocenyl compound is able to enhance its combustion catalytic efficiency.
Identifying employer perceptions of recognised DM practice domains
Authors: Coduti Wendy , King Cherie
Published: November 2014

In the United States, workers’ compensation law is state-specific, and employee benefits including health care costs are born primarily by the employer. In response to cost increases in medical treatment and absences due to illnesses and injuries occupational or non-occupational, the practice of Disability Management (DM) has continued to evolve. The purpose of Disability Management is to reduce the incidents of employee absences, whether due to illness, injury, or other causes. There is a distinct paucity of meaningful analyses of the history and emerging evidences in the DM field. As a more integrated approach to disability management, both a theoretical understanding and an evidence-based practice is sought by each stakeholder in order to structure the evolution of practice and to document consistent ROI metrics. Theoretical underpinnings, historical evolution of disability and absence management, and specific evidence-based trends emerging in the field form the foundation of these standards. This study is a workplace approach that begins to define standards of practice to integrate disability management, health and wellness, and absence management. The purpose of this study is to collect data to comprehend how employers perceive their own awareness, importance, and feelings of preparedness pertaining to the primary practice domains identified in DM. This data will be obtained through an electronic survey using rating scales with an online questionnaire which will include descriptive and ex post facto design components. The survey items were developed by these authors in collaboration with other colleagues known in the field of Disability Management. Descriptive statistics will be computed for the employer participants characteristics based upon the demographic portion of the online questionnaire. The population of interest in this study is national or international employer(s) that have deployed or interested to develop Disability Management program(s) at their worksite(s). The specific type of employees/partners with these employers include: Occupational Health Practitioners, Department Heads and Supervisors, Human Resources personnel and Risk Management/Safety Personnel. The findings from this study will help identify employer perceptions of recognized DM practice domains, identify potential training needs of employers, and assist in developing standards of practice approach to workplace disability, health/wellness, and absence management, and DM educational standards. In addition, employers will be able identify their position on the continuum of the model disability management that evolves to engage practices integrating health and wellness, absence management, and productivity management. Maturation benchmarks will place the employer in a continuous improvement mode towards a workplace with a healthier workforce in a healthier community. Information will also be beneficial to the literature, and capacity development of students and practitioners in the field of Disability Management.