bluuebunny/crossref_metadata_2025 huggingface dataset:
Multi-Objective and Multi-Point Aerodynamic Optimization of Transonic Fan Blades
Authors: Khelghatibana Maryam , Trépanier Jean-Yves , Tribes Christophe , Nichols Jason
Published: March 2015

A multi-objective and multi-point optimization methodology is developed for aerodynamic design of transonic fan blades. The optimization method aims to increase design efficiency, near stall efficiency and stall margin while maintaining the required design pressure ratio and high speed choke margin. Numerical analyses are performed by solving three-dimensional Reynolds-Averaged Navier-Stokes equations combined with shear stress turbulence model. A multi-level blade parameterization is employed to modify the blade geometry. The proposed method is applied to redesign NASA rotor 67. First, an optimization case with considering two operating conditions at peak efficiency and near stall is performed to demonstrate the relation between near stall efficiency and stall margin. An investigation on Pareto optimal solutions of this optimization shows that the stall margin is increased with improving near stall efficiency. Then, in order to maintain the required choke margin, an operating point at high speed choked flow is added to the optimization process. A final optimized design is selected by considering the interaction of design requirements at all three operating points. The new design presents higher efficiency and stall margin without any reduction in the chocking mass flow rate.
Structural Analysis of Variable Stiffness Laminated Plates Using First-Order Shear Deformation Theory
Authors: Akbarzadeh A. H. , Arian Nik M. , Pasini D.
Published: March 2015

Constant and variable stiffness strategies have been developed to design a composite laminate. With the former, each layer is designed with straight fibers that have the highest stiffness and strength in the fiber direction. With the latter, on the other hand, the stiffness can change within each layer by placing the fibers along a curvilinear fiber path. A variable stiffness design results in improved structural performance, as well as opens up opportunities to search for trade-off among structural properties. During the manufacture of a variable stiffness design with Automated Fiber Placement, certain defects in the form of gaps and overlaps could appear within the laminate and affect the laminate performance. In this study, we use the first-order shear deformation theory to assess the effect of transverse shear stresses on the critical buckling load, free and forced vibration of a variable stiffness laminate with embedded defects, an issue so far rarely examined in literature. The governing differential equations for the static analysis are first derived. A semi-analytic solution is then obtained using the hybrid Fourier-Galerkin method and the numeric time integration technique. The eigenvalue analysis is also conducted to determine the fundamental frequency and critical buckling load of the plate. It is found that the behavior of a variable stiffness plate is much more affected by the shear stresses than a constant stiffness plate. Ignoring the effect of transverse shear stresses results in 34% error in the predicted buckling load of a variable stiffness laminate with overlaps and a length-to-thickness ratio of 10.
Application of SMC and NLFC Into a PRRR Robotic Arm
Authors: Hatamleh Khaled S. , Al-Shabi Mohammad , Khasawneh Qais A. , Al-Asal Mohammad Abo
Published: March 2015

Industrial robotic arms are widely used nowadays. Accuracy and efficiency that fulfill user’s requirements are achieved through robust controller. This paper investigates dynamics modeling and control of a four DOF (PRRR) robot that is dedicated to perform a Pick-and-Place move of a certain product. The arm is undergoing manufacturing process. Forward and inverse kinematics solutions are introduced to solve the joint space trajectories associated with the desired End Effector (EE) Cartesian space path. The performance of two controllers under the presence of model uncertainties is inspected through a simulation study; Non-Linear Feedback Control (NLFC) and Sliding Mode Control (SMC) are designed and tested over the required joint space trajectories and Cartesian space path. Results showed that NLFC achieved better results than SMC in terms of RMSE when model uncertainties were absent. However, when model uncertainties were introduced, SMC performance was more robust than NLFC. Simulation results are very encouraging towards using the SMC over the actual robotic arm.
Semi Active Hand Orthosis
Authors: Flores-Luna Rosa I. , Torres-Martínez Pol D. , García-del-Gállego Mariano , Dorador-Gonzalez Jesus M.
Published: March 2015

This paper presents a semi active orthosis designed for recovering the mobility on a paralyzed hand because of a fifth cervical injury, C5. The orthosis is based on a six bar mechanism and a circular slide, using the hand as a part of the mechanism. Other similar devices were developed around the world, nevertheless this design is independent of an actuator, and can be used with or without one. As a result, the mechanism and tests with the user are presented; the user of the mechanism can hold different objects with his hand using the orthosis.
Material Property Testing of 3D-Printed Specimen in PLA on an Entry-Level 3D Printer
Authors: Letcher Todd , Waytashek Megan
Published: March 2015

An entry level consumer priced 3d-printer, the MakerBot Replicator 2x, was used to print specimen to conduct tensile, flexural and fatigue testing. Average priced, generic brand PLA material was used (similar to the filament a home user may purchase). Specimen were printed at raster orientation angles of 0°, 45° and 90° to test orientation effects on part strength. PLA filament was also tensile tested.

Tensile testing of the 3d-printed specimens showed that the 45° raster orientation angle made the strongest specimen at an ultimate tensile strength of 64 MPa. The 0° and 90° raster orientation were not much less at 58 MPa and 54 MPa. A 3-point bending fixture was used to conduct flexural testing on printed specimen. For this type of testing, the 0° raster orientation produced the strongest parts with an ultimate bending stress of 102 MPa. Both the 45° and 90° raster orientations had similar results at 90 MPa and 86 MPa. For the fatigue testing, there was no clear best option, but there was a clearly worst option, the 90° raster orientation. This orientation clearly had lower fatigue lives than either of the other two raster orientations. The other two raster orientations, 0° and 45°, were very similar. PLA filament testing using bollard style grips, showed that the PLA filament exhibited mechanical properties similar to that of printed specimen — when tested at high enough strain rates that creep damage didn’t play a significant role. This may lead to implications for recycling failed 3d-print jobs and turning it back into reusable filament.
Investigation of Dynamic and Control of Robots’ Cooperation in Assembling Process
Authors: Dehkordi Ashkan Nourizadeh , Keshmiri Mehdi , Keshmiri Mohammad
Published: March 2015

Assembling and fitting parts together can be considered as one of the most practical but also challenging process in robotics. Various applications are conceivable such as spatial ones where accessibility is reduced or in construction fields where huge forces have to be dealt with in a meticulous manner. In this paper, the cooperation of two robots during the complete assembling process of two structural parts from the approaching phase to the fitting stage is investigated. In the approaching phase for taking the parts closer, the two large construction parts may collide due to the inertia of motion, causing considerable impact forces even with the slightest relative velocity. This issue presents important control challenges as the effects of this local impact may be transferred throughout the system’s frame, affecting all other elements and inducing instability. Finally after connection of these two parts is established, the whole frame is transported to any desired location by cooperative operation of the two robots. Each step requires a particular controller to deal with different system’s dynamics that occur during the whole process.
Energy Dissipation Rate Control for Planar Biped Walking Robot Based on the Property of Passive Dynamic Walking
Authors: Azimi Mohsen , Hairi Yazdi M. R.
Published: March 2015

Several control methods based on passive dynamic walking have been proposed by researchers to provide an efficient human-like biped walking robot. For most of these passive based controllers the main idea is to shape the robot’s energy level during each Single Support Phase (SSP) to restore the mechanical energy which has been lost in the previous Impact Phases (IP). In this paper, instead of controlling the energy restoration rate during each SSP, a new strategy is introduced which provides a stable walking by controlling the energy dissipation rate during each IP. Subsequently, this method is applied to an anti-trunk biped robot with lockable knee joints to realize an active dynamic walking on level ground. Simulation results show, the proposed method is effective.
Crystallization in Nano-Confinement Seeded by a Nanocrystal: A Molecular Dynamics Study
Authors: Pan Heng , Grigoropoulos Costas
Published: March 2015

Seeded crystallization and solidification in nanoscale confinement volumes has become an important and complex topic in nanomanufacturing. Due to the complexity and limitations in observing nanoscale crystallization, computer simulation can provide valuable details for supporting and interpreting experimental observations. In this article, seeded crystallization from nano-confined liquid, as represented by the crystallization of a suspended gold nano-droplet seeded by a pre-existing gold nanocrystal seed, was investigated using molecular dynamics simulations in canonical (NVT) ensemble. We found that the crystallization temperature depends on nano-confinement volume, crystal orientation and seed size as explained by classical two-sphere model and Gibbs-Thomson effect.
Adaptive Fuzzy Computed Torque Controller for Under Actuated Bipedal Robot
Authors: Ansari Hamzeh , Pourgol Mohammad Mohammad , Ghanbari Ahmad
Published: March 2015

The primary goal of this paper is to develop and test a new controller for an under-actuated bipedal robot. This controller handles adequately some limitations existing in other similar robot controllers. Fuzzy controller is used in this research in order to tuning the gain of controller adaptively. Tuning parameters lead to robust character and high performance for uncertain movements during the walking. Using adaptive fuzzy computed torque controller, it provide conditions through which i) adaptive fuzzy part adjusts parameters of the system and ii) computed torque part provide a nonlinear control simultaneously. Use of these two advantages lead to reduce uncertainty effects during walking. Finally the Matlab software is developed to evaluate the effectiveness for stability of proposed controller.
Analytical Solution of Two Coupled Oscillators With a Nonlinear Coupling Resorting Force
Authors: Al-Shudeifat Mohammad A. , Burton Thomas D.
Published: March 2015

An approach for accurate analytical solution of a two degree-of-freedom nonlinear dynamical system coupled with a strongly nonlinear restoring force is presented here. The approach is based on the application of the local equivalent linear stiffness method (LELSM) to linearize the nonlinear coupling stiffness in the system based on the nonlinear frequency calculation. Consequently, the system can be decoupled into two forced single degree-of-freedom subsystems by replacing the nonlinear coupling force with a forcing function where the solution can be analytically obtained. Different combinations of the positive and negative linear and cubic stiffness components are considered in the nonlinear coupling force. For all considered stiffness combinations, the obtained analytical solution strongly agrees with the numerical simulation of the system. In addition, the internal resonance is found not to significantly affect the accuracy of the analytical solution.
Adaptive Bone Remodeling to Capture the Trabecular Bone Morphology of the Proximal Femur
Authors: Banijamali S. Mohammad Ali , Oftadeh Ramin , Vaziri Ashkan , Nayeb-Hashemi Hamid
Published: March 2015

In this study, a model of femur which resembles bone natural structure has been developed. The model initially consists of a solid shell representing cortical bone encompassing a cubical network of interconnected rods with circular cross-sections representing trabecular bone part. A computational efficient program has been developed which iteratively changes the structure of trabecular bone by keeping the local stress in the structure within a defined stress range. The stress is controlled by either enhancing existing beam elements or removing beams from the initial trabecular frame structure. Trabecular bone structure is obtained for two load cases: walking and stair climbing. The results show that as the magnitude of the loads increase, the internal structure gets denser in critical zones. The higher density is achieved using loading associated with the stair climbing. Walking which is considered as the routine daily activity, results in the less internal density in different regions of the bone. The results show that the converged bone architecture consisting of rods and plates are consistent with the natural bone morphology of femur. Furthermore, the bone volume fraction at the critical regions of the converged structure is in a good agreement with previously measured data obtained from combinations of Dual X-ray Absorptiometry (DXA) and Computed Tomography (CT).
Systemic administration of epothilone B promotes axon regeneration after spinal cord injury
Authors: Ruschel Jörg , Hellal Farida , Flynn Kevin C. , Dupraz Sebastian , Elliott David A. , Tedeschi Andrea , Bates Margaret , Sliwinski Christopher , Brook Gary , Dobrindt Kristina , Peitz Michael , Brüstle Oliver , Norenberg Michael D. , Blesch Armin , Weidner Norbert , Bunge Mary Bartlett , Bixby John L. , Bradke Frank
Published: March 2015

Progress toward fixing a broken back?

Axon regeneration after a spinal cord injury requires interference with neuronal mechanisms to promote axon extension and early suppression of scar formation. Microtubule stabilization could provide, in principle, a basis for such intervention. Ruschel
et al.
used animal models of spinal cord injury, time-lapse imaging in vivo, primary neuronal cultures, and behavioral studies to tackle this challenge (see the Perspective by Tran and Silver). They showed that epothilone B, a U.S. Food and Drug Administration–approved microtubule-stabilizing drug that can cross the blood-brain barrier, does promote functional axon regeneration, even after injury.

Science
, this issue p.
347
; see also p.
285
Whole-Genome Sequence of “Candidatus Rickettsia asemboensis” Strain NMRCii, Isolated from Fleas of Western Kenya
Authors: Jima Dereje D. , Luce-Fedrow Alison , Yang Yu , Maina Alice N. , Snesrud Erik C. , Otiang Elkanah , Njenga Kariuki , Jarman Richard G. , Richards Allen L. , Hang Jun
Published: March 2015

Herein we present the draft genome sequence and annotation of “Candidatus Rickettsia asemboensis” strain NMRCii. “
Ca.
Rickettsia asemboensis” is phylogenetically related to but distinct from the flea-borne spotted fever pathogen
Rickettsia felis
. “
Ca.
Rickettsia asemboensis” was initially identified in and subsequently isolated from Ctenocephalides cat and dog fleas from Kenya.
Genomes of Geoalkalibacter ferrihydriticus Z-0531
T
and Geoalkalibacter subterraneus Red1
T
, Two Haloalkaliphilic Metal-Reducing Deltaproteobacteria
Authors: Badalamenti Jonathan P. , Krajmalnik-Brown Rosa , Torres César I. , Bond Daniel R.
Published: March 2015

We sequenced and annotated genomes of two haloalkaliphilic
Deltaproteobacteria
,
Geoalkalibacter ferrihydriticus
Z-0531
T
(DSM 17813) and
Geoalkalibacter subterraneus
Red1
T
(DSM 23483). During assembly, we discovered that the DSMZ stock culture of G. subterraneus was contaminated. We reisolated G. subterraneus in axenic culture and redeposited it in DSMZ and JCM.
Draft Genome Sequence of the Filamentous Fungus Penicillium paxilli (ATCC 26601)
Authors: Berry Daniel , Cox Murray P. , Scott Barry
Published: March 2015

Penicillium paxilli ATCC 26601 is an asexual filamentous fungal species known for its production of the mycotoxin paxilline. We present here the 35-Mb draft genome sequence for this organism.
Complete Genome Sequence of Bacillus subtilis subsp. subtilis Strain 3NA
Authors: Reuß Daniel R. , Schuldes Jörg , Daniel Rolf , Altenbuchner Josef
Published: March 2015

Bacillus subtilis
3NA reaches high cell densities during fed-batch fermentation and is an interesting target for further optimization as a production strain. Here, we announce the full genome of
B. subtilis
3NA. The presence of specific
Bacillus subtilis
168 and W23 genetic features suggests that 3NA is a hybrid of these strains.
Genome Sequence Analysis Reveals Evidence of Quorum-Sensing Genes Present in Aeromonas hydrophila Strain M062, Isolated from Freshwater
Authors: Chan Kok-Gan , Tan Wen-Si , Chang Chien-Yi , Yin Wai-Fong , Mumahad Yunos Nina Yusrina
Published: March 2015

Aeromonas hydrophila
has emerged worldwide as a human pathogen. Here, we report the draft whole-genome sequence of a freshwater isolate from Malaysia, A. hydrophila strain M062, and its
N
-acylhomoserine lactone genes are also reported here.
Draft Genome Sequence of Bordetella avium Nh1210, an Outbreak Strain of Lockjaw Syndrome
Authors: Moreno Luisa Z. , Knöbl Terezinha , Grespan André A. , Felizardo Maria R. , Gomes Cleise R. , Ferreira Thais S. P. , Xavier de Oliveira Maria Gabriela , Myriantheus Livia , Moreno Andrea Micke
Published: March 2015

Bordetella avium
is a highly contagious bacterium that infects the upper respiratory tract of birds. B. avium Nh1210 is an outbreak strain of lockjaw syndrome in juvenile cockatiel chicks (Nymphicus hollandicus). Here, we report the draft genome sequence of strain Nh1210.
Cross-sectional comparison of point-of-care with laboratory HbA1cin detecting diabetes in real-world remote Aboriginal settings
Authors: Marley Julia V , Oh May S , Hadgraft Nyssa , Singleton Sally , Isaacs Kim , Atkinson David
Published: March 2015

Objectives

To determine if point-of-care (POC) glycated haemoglobin (HbA1c) is sufficiently accurate in real-world remote settings to predict or exclude the diagnosis of diabetes based on laboratory HbA1cmeasurements.

Design

Cross-sectional study comparing POC capillary HbA1cresults with corresponding venous HbA1clevels measured in a reference laboratory.

Participants

Aboriginal patients ≥15 years old who were due for diabetes screening at the participating clinics were invited to participate. Two hundred and fifty-five Aboriginal participants were enrolled and 241 were included in the analysis.

Setting

6 primary healthcare sites in the remote Kimberley region of Western Australia from September 2011 to November 2013.

Main outcome measures

Concordance and mean differences between POC capillary blood HbA1cmeasurement and laboratory measurement of venous blood HbA1clevel; POC capillary blood HbA1cequivalence value for screening for diabetes or a high risk of developing diabetes; sensitivity, specificity and positive-predictive value for diagnosing and screening for diabetes; barriers to conducting POC testing.

Results

Concordance between POC and laboratory results was good (ρ=0.88, p<0.001). The mean difference was −0.15% (95% limits of agreement, −0.67% to 0.36%). POC HbA1cmeasurements ≥6.5%, 48 mmol/mol had a specificity of 98.2% and sensitivity of 73.7% for laboratory measurements ≥6.5%. The POC equivalence value for screening for diabetes or a high risk of developing diabetes was ≥5.7%, 39 mmol/mol (sensitivity, 91%; specificity, 76.7% for laboratory measurements ≥6.0%, 42 mmol/mol). Staff trained by other clinic staff ‘on the job’ performed as well as people with formal accredited training. Staff reported difficulty in maintaining formal accreditation.

Conclusions

POC HbA1ctesting is sufficiently accurate to be a useful component in screening for, and diagnosing, diabetes in remote communities. Limited local training is adequate to produce results comparable to laboratory results and accreditation processes need to reflect this.
Improving pain assessment and managment in stroke patients
Authors: Nesbitt Julian , Moxham Sian , ramadurai gopinath , Williams Lucy
Published: March 2015

Stroke patients can experience a variety of pain. Many stroke patients have co-morbidities such as osteoporosis, arthritis or diabetes causing diabetic neuropathy. As well as pain from other long term conditions, stroke patients can experience central post-stroke pain, headaches, and musculoskeletal issues such as hypertonia, contractures, spasticity, and subluxations. These stroke patients can also have communication difficulties in the form of expressive dysphasia and/or global aphasia. Communication difficulties can result in these patients not expressing their pain and therefore not having it assessed, leading to inadequate pain relief that could impact their rehabilitation and recovery.

By implementing an observational measurement of pain such as the Abbey pain scale, patients with communication difficulties can have their pain assessed and recorded. Initially 30% of patients on the acute stroke ward did not have their pain assessed and adequately recorded and 15% of patients had inadequate pain relief. The patient was assessed if they were in pain and therefore not receiving adequate pain relief by measuring their pain on the Abbey pain scale. After introducing the Abbey pain scale and creating a nurse advocate, an improvement was shown such that only 5% of patients did not have their pain recorded and all had adequate pain relief.
Giving ourselves a head start: improving the quality of documentation of referrals to neurosurgery
Authors: Storey Madeleine , Webster Simon
Published: March 2015

Referrals to neurosurgical units are regularly made by doctors in the emergency department (ED), intensive care and acute medicine, following brain injuries sustained by both traumatic and non-traumatic processes. Although some centres accept electronic referrals, many still rely on telephone conversations with a specialist registrar. The flaw in this style of communication is that only information volunteered or requested is relayed. Furthermore, documentation of these dialogues is often incomplete, omitting specific and vital details. Inconsistent advice from referral centres on the management of such brain injury cases had been highlighted, prompting a review of practices at local level in order to improve quality of patient care.

The aim of this project was to identify the current level of documentation and improve this through departmental education and implementation of a referral proforma. National guidelines and a literature review were used to formulate the gold standard for high quality documentation.

ED patient notes were retrospectively reviewed over a three month period, assessing adequacy of referral documentation to a neurosurgical centre against the parameters previously set. Initial audit results and specific case studies were presented to ED team members at an educational meeting. A "record of telephone referral to neurosurgery" (RTRN) form was also introduced. Re-audit against the same set of standards was conducted to assess any change in level of documentation and use of the form itself.

The results of this project have shown that, although departmental education improves clinical practice, following the introduction and use of a protocol such as the RTRN there was a significant improvement in the level, and therefore quality of, documentation.
Ferulic acid exerts its antidiabetic effect by modulating insulin-signalling molecules in the liver of high-fat diet and fructose-induced type-2 diabetic adult male rat
Authors: Narasimhan Akilavalli , Chinnaiyan Mayilvanan , Karundevi Balasubramanian
Published: March 2015

Ferulic acid (FA) is a phenolic phytochemical known for its antidiabetic property The present study is designed to evaluate the mechanism behind its antidiabetic property in high-fat and fructose-induced type 2 diabetic adult male rats. Animals were divided into 5 groups: (i) control, (ii) diabetic control, (iii) diabetic animals treated with FA (50 mg/(kg body weight·day)–1, orally) for 30 days, (iv) diabetic animals treated with metformin (50 mg/(kg body weight·day)–1, orally) for 30 days, and (v) control rats treated with FA. FA treatment to diabetic animals restored blood glucose, serum insulin, glucose tolerance, and insulin tolerance to normal range. Hepatic glycogen concentration, activity of glycogen synthase, and glucokinase were significantly decreased, whereas activity of glycogen phosphorylase and enzymes of gluconeogenesis (phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase)) were increased in diabetic animals and FA restored these to normal levels similar to that of metformin. FA improved the insulin signalling molecules and reduced the negative regulators of insulin signalling. The messenger RNA of gluconeogenic enzyme genes (PEPCK and G6Pase) and the interaction between forkhead transcription factor-O1 and promoters of gluconeogenic enzyme genes (PEPCK and G6Pase) was reduced significantly by ferulic acid. It is concluded from the present study that FA treatment to type 2 diabetic rats improves insulin sensitivity and hepatic glycogenesis but inhibits gluconeogenesis and negative regulators of insulin signalling to maintain normal glucose homeostasis.
Observed trends and climate projections affecting marine ecosystems in the Canadian Arctic
Authors: Steiner Nadja , Azetsu-Scott Kumiko , Hamilton Jim , Hedges Kevin , Hu Xianmin , Janjua Muhammad Y. , Lavoie Diane , Loder John , Melling Humfrey , Merzouk Anissa , Perrie William , Peterson Ingrid , Scarratt Michael , Sou Tessa , Tallmann Ross
Published: March 2015

Past trends and future projections of key atmospheric, oceanic, sea ice, and biogeochemical variables were assessed to increase our understanding of climate change impacts on Canadian Arctic marine ecosystems. Four subbasins are evaluated: Beaufort Sea, Canadian Arctic Archipelago, Baffin Bay/Davis Strait, and Hudson Bay Complex. Limited observations, especially for ecosystem variables, compromise the trend analyses. Future projections are predominately from global models with few contributions from available marine basin scale models. The assessment indicates a significant increase in air temperature, slight increases in precipitation and snow depth, and appreciable changes in atmospheric circulation patterns. Projections suggest an increase in storm strength and size, leading to enhanced storm surges and coastal erosion, a slight increase in wave heights, increases in gustiness, and small changes in mean wind speed. An Arctic-wide decrease in the extent of multiyear ice and a spatial and temporal increase in ice-free waters in summer have been observed and are projected to continue into the future. Limited observations of ocean properties show local freshening (Beaufort Sea) and summer warming (Baffin Bay). These trends are projected to continue along with localized strengthening in stratification. Increased ocean acidification has been observed and is projected to continue throughout the Canadian Arctic, leading to severely decreased saturation states of calcium carbonate (aragonite and calcite). Qualitative analysis of biological observations indicate large regional differences. Increased primary production and double bloom development is seen in areas of sea ice retreat where nutrient supply is sufficient, and unchanged or reduced production is seen where nutrients are low or suppressed in response to enhanced stratification. Future primary production projections show inconsistent results, with light-dependent increase or nutrient-limited decrease dominating, dependent on the model. For the next decade, natural intradecadal variability is expected to be of similar importance as longer-term trends. To improve our capacity to assess and project climate change adaptation in marine ecosystems, more consistent observations are needed, especially over marine areas and for biogeochemical variables. Higher resolution basin-scale models are also required to provide locally applicable projections relevant for Arctic communities and management units.
TIME VARYING ASIAN STOCK MARKET INTEGRATION
Authors: BATTEN JONATHAN A. , MORGAN PETER , SZILAGYI PETER G.
Published: March 2015

We employ an asset pricing framework with varying estimation lengths to show that there has been an increasing degree of integration between Asian and international stock markets, but very little with Japan. This finding is consistent with prior studies and highlights the impact of recent regulatory and economic reform undertaken throughout the region. Our results show that instability in the asset variance structure underpins the observed varying degrees of financial market integration. In particular, modeling integration using shorter estimation periods helps explain the time varying nature of financial market integration and the benefits that may accrue to international and domestic investors.
Modern studies of the Deuteron: From the lab frame to the light front
Authors: Boeglin Werner , Sargsian Misak
Published: March 2015

We review the recent progress made in studies of deuteron structure at small internucleon distances. This progress is largely facilitated by the new generation of experiments in deuteron electrodisintegration carried out at unprecedentedly high momentum transfer. The theoretical analysis of these data confirms the onset of the high energy eikonal regime in the scattering process which allows one to separate long-range nuclear effects from the effects genuinely related to the short distance structure of the deuteron. Our conclusion is that for the first time the deuteron is probed at relative momenta beyond 300 MeV/c without dominating long-range effects. As a result, at these large nucleon momenta the cross-section is sensitive to the nuclear dynamics at subfermi distances. Due to large internal momenta involved we are dealing with the relativistic bound state that is best described by the light-cone momentum distribution of nucleons in the deuteron. We present the first attempt of extracting the deuteron light-cone momentum distribution function from data and discuss the importance of this quantity for studies of quantum chromodynamics (QCD) structure of the bound nucleon in deep inelastic scattering (DIS) off the deuteron. We conclude the review giving an outlook of the next generation of high energy experiments which will extend our reach to much smaller distances in the deuteron.
The Malliavin calculus and hypoelliptic differential operators
Authors: Bell Denis
Published: March 2015

This article is intended as an introduction to Malliavin's stochastic calculus of variations and his probabilistic approach to hypoellipticity. Topics covered include an elementary derivation of the basic integration by parts formulae, a proof of the probabilistic version of Hörmander's theorem as envisioned by Malliavin and completed by Kusuoka and Stroock, and an extension of Hörmander's theorem valid for operators with degeneracy of exponential type due to the author and S. Mohammed.
Second quantisation for skew convolution products of infinitely divisible measures
Authors: Applebaum David , van Neerven Jan
Published: March 2015

Suppose λ1 and λ2 are infinitely divisible Radon measures on real Banach spaces E1 and E2, respectively and let T : E1 → E2 be a Borel measurable mapping so that T(λ1) * ρ = λ2 for some Radon probability measure ρ on E2. Extending previous results for the Gaussian and the Poissonian case, we study the problem of representing the "transition operator" PT : Lp(E2, λ2) → Lp(E1, λ1) given by [Formula: see text] as the second quantisation of a contraction operator acting between suitably chosen "reproducing kernel Hilbert spaces" associated with λ1 and λ2.
Scattering of solutions to the fourth-order nonlinear Schrödinger equation
Authors: Hayashi Nakao , Mendez-Navarro Jesus A. , Naumkin Pavel I.
Published: March 2015

We consider the Cauchy problem for the fourth-order nonlinear Schrödinger equation [Formula: see text] where [Formula: see text] [Formula: see text] We introduce the factorization for the free evolution group to prove the large time asymptotics of solutions.
Mechanism of the Strain Rate Effect of Metal Foams with Numerical Simulations of 3D Voronoi Foams during the Split Hopkinson Pressure Bar Tests
Authors: Yang B. , Liu Z. J. , Tang L. Q. , Jiang Z. Y. , Liu Y. P.
Published: March 2015

With the demand of lightweight structure, more and more metal foams were employed as impact protection and efficient energy absorption materials in engineering fields. But, results from different impact experiments showed that the strain rate sensitivity of metal foams were different or even controversial. In order to explore the true hiding behind the controversial experimental data about the strain rate sensitivity of metal foams, numerical simulations of split Hopkinson pressure bar (SHPB) tests of the metal foams were carried out by finite element methods. In the analysis, cell structures of metal foams were constructed by means of 3D Voronoi, and the matrix metal was assumed to be no strain rate sensitivity, which helps to learn the strain rate effects quantitatively by the foam structures. Numerical simulations showed that the deformation of the metal foam specimen is not uniform during the SHPB tests along the specimen, and the strain–stress relations of the metal foams at two ends of the specimen are different; there exists strain rate sensitivity of the metal foams even the matrix metal has no strain rate sensitivity, when the strain of the metal foams is defined by the displacement difference between the ends of the specimen; localized deformation of the metal foams and the inertia effect of matrix metal are the two main contributions to the strain rate sensitivity of the metal foams.
Bicharacteristics and Fourier integral operators in Kasner spacetime
Authors: Esposito Giampiero , Battista Emmanuele , Di Grezia Elisabetta
Published: March 2015

The scalar wave equation in Kasner spacetime is solved, first for a particular choice of Kasner parameters, by relating the integrand in the wave packet to the Bessel functions. An alternative integral representation is also displayed, which relies upon the method of integration in the complex domain for the solution of hyperbolic equations with variable coefficients. In order to study the propagation of wave fronts, we integrate the equations of bicharacteristics which are null geodesics, and we are able to express them, for the first time in the literature, with the help of elliptic integrals for another choice of Kasner parameters. For generic values of the three Kasner parameters, the solution of the Cauchy problem is built through a pair of integral operators, where the amplitude and phase functions in the integrand solve a coupled system of partial differential equations. The first is the so-called transport equation, whereas the second is a nonlinear equation that reduces to the Eikonal equation if the amplitude is a slowly varying function. Remarkably, the analysis of such a coupled system is proved to be equivalent to building first an auxiliary covariant vector having vanishing divergence, while all nonlinearities are mapped into solving a covariant generalization of the Ermakov–Pinney equation for the amplitude function. Last, from a linear set of equations for the gradient of the phase one recovers the phase itself. This is the parametrix construction that relies upon Fourier–Maslov integral operators, but with a novel perspective on the nonlinearities in the dispersion relation. Furthermore, the Adomian method for nonlinear partial differential equations is applied to generate a recursive scheme for the evaluation of the amplitude function in the parametrix. The resulting formulas can be used to build self-dual solutions to the field equations of noncommutative gravity, as has been shown in the recent literature.
LAND USE CHANGE, CARBON, AND BIOENERGY RECONSIDERED
Authors: SEDJO ROGER A. , SOHNGEN BRENT , RIDDLE ANNE
Published: March 2015

Many environmentalists are concerned that renewable bioenergy, such as corn or wood ethanol will not reduce carbon emissions but will deplete forests. Using a general stylized forest sector management model, our study examines the economic potential of traditional industrial forests and supplemental dedicated fuelwood plantations to produce biomass on submarginal lands not suitable for most crop agriculture. The study finds that forests can economically produce large levels of biofuel without compromising crop production, thereby avoiding price pressures that lead to cropland conversion and carbon emissions.
AXL Is a Logical Molecular Target in Head and Neck Squamous Cell Carcinoma
Authors: Brand Toni M. , Iida Mari , Stein Andrew P. , Corrigan Kelsey L. , Braverman Cara M. , Coan John P. , Pearson Hannah E. , Bahrar Harsh , Fowler Tyler L. , Bednarz Bryan P. , Saha Sandeep , Yang David , Gill Parkash S. , Lingen Mark W. , Saloura Vassiliki , Villaflor Victoria M. , Salgia Ravi , Kimple Randall J. , Wheeler Deric L.
Published: March 2015

Purpose: Head and neck squamous cell carcinoma (HNSCC) represents the eighth most common malignancy worldwide. Standard-of-care treatments for patients with HNSCC include surgery, radiation, and chemotherapy. In addition, the anti-EGFR monoclonal antibody cetuximab is often used in combination with these treatment modalities. Despite clinical success with these therapeutics, HNSCC remains a difficult malignancy to treat. Thus, identification of new molecular targets is critical.

Experimental Design: In the current study, the receptor tyrosine kinase AXL was investigated as a molecular target in HNSCC using established cell lines, HNSCC patient-derived xenografts (PDX), and human tumors. HNSCC dependency on AXL was evaluated with both anti-AXL siRNAs and the small-molecule AXL inhibitor R428. Furthermore, AXL inhibition was evaluated with standard-of-care treatment regimens used in HNSCC.

Results: AXL was found to be highly overexpressed in several models of HNSCC, where AXL was significantly associated with higher pathologic grade, presence of distant metastases, and shorter relapse-free survival in patients with HNSCC. Further investigations indicated that HNSCC cells were reliant on AXL for cellular proliferation, migration, and invasion. In addition, targeting AXL increased HNSCC cell line sensitivity to chemotherapy, cetuximab, and radiation. Moreover, radiation-resistant HNSCC cell line xenografts and PDXs expressed elevated levels of both total and activated AXL, indicating a role for AXL in radiation resistance.

Conclusions: This study provides evidence for the role of AXL in HNSCC pathogenesis and supports further preclinical and clinical evaluation of anti-AXL therapeutics for the treatment of patients with HNSCC. Clin Cancer Res; 21(11); 2601–12. ©2015 AACR.
Homologous Mutation to Human BRAF V600E Is Common in Naturally Occurring Canine Bladder Cancer—Evidence for a Relevant Model System and Urine-Based Diagnostic Test
Authors: Decker Brennan , Parker Heidi G. , Dhawan Deepika , Kwon Erika M. , Karlins Eric , Davis Brian W. , Ramos-Vara José A. , Bonney Patty L. , McNiel Elizabeth A. , Knapp Deborah W. , Ostrander Elaine A.
Published: March 2015

Targeted cancer therapies offer great clinical promise, but treatment resistance is common, and basic research aimed at overcoming this challenge is limited by reduced genomic and biologic complexity in artificially induced rodent tumors compared with their human counterparts. Animal models that more faithfully recapitulate genotype-specific human pathology could improve the predictive value of these investigations. Here, a newly identified animal model for oncogenic BRAF-driven cancers is described. With 20,000 new cases in the United States each year, canine invasive transitional cell carcinoma of the bladder (InvTCC) is a common, naturally occurring malignancy that shares significant histologic, biologic, and clinical phenotypes with human muscle invasive bladder cancer. In order to identify somatic drivers of canine InvTCC, the complete transcriptome for multiple tumors was determined by RNAseq. All tumors harbored a somatic mutation that is homologous to the human BRAF(V600E) mutation, and an identical mutation was present in 87% of 62 additional canine InvTCC tumors. The mutation was also detectable in the urine sediments of all dogs tested with mutation-positive tumors. Functional experiments suggest that, like human tumors, canine activating BRAF mutations potently stimulate the MAPK pathway. Cell lines with the mutation have elevated levels of phosphorylated MEK, compared with a line with wild-type BRAF. This effect can be diminished through application of the BRAF(V600E) inhibitor vemurafenib. These findings set the stage for canine InvTCC as a powerful system to evaluate BRAF-targeted therapies, as well as therapies designed to overcome resistance, which could enhance treatment of both human and canine cancers

Implications: This study demonstrates the activating BRAF mutation (V600E), which is found in multiple human cancers, is a driver of canine InvTCC, and highlights a urine-based test for quick diagnosis. Mol Cancer Res; 13(6); 993–1002. ©2015 AACR.
Clinical Experience With Novel Oral Anticoagulants for Thromboprophylaxis After Elective Hip and Knee Arthroplasty
Authors: Messerschmidt Cory , Friedman Richard J.
Published: March 2015

Anticoagulant medications help to reduce the risk of thromboembolic events after total hip arthroplasty and total knee arthroplasty. Traditionally, this has been accomplished with medications, such as low–molecular-weight heparin and warfarin. However, these traditional anticoagulants possess a variety of shortcomings that leave much room for improvement. A new class of oral anticoagulants is now available, and present a more convenient option for safe and efficacious thromboprophylaxis in post arthroplasty patients, particularly in the outpatient setting. This review focuses on the direct thrombin inhibitor, dabigatran, and the selective factor Xa inhibitors, rivaroxaban and apixaban, and the clinical data to date about their use in total hip arthroplasty and total knee arthroplasty patients.
FKBPL Is a Critical Antiangiogenic Regulator of Developmental and Pathological Angiogenesis
Authors: Yakkundi Anita , Bennett Rachel , Hernández-Negrete Ivette , Delalande Jean-Marie , Hanna Mary , Lyubomska Oksana , Arthur Kenneth , Short Amy , McKeen Hayley , Nelson Laura , McCrudden Cian M. , McNally Ross , McClements Lana , McCarthy Helen O. , Burns Alan J. , Bicknell Roy , Kissenpfennig Adrien , Robson Tracy
Published: March 2015

Objective—

The antitumor effects of FK506-binding protein like (FKBPL) and its extracellular role in angiogenesis are well characterized; however, its role in physiological/developmental angiogenesis and the effect of
FKBPL
ablation has not been evaluated. This is important as effects of some angiogenic proteins are dosage dependent. Here we evaluate the regulation of FKBPL secretion under angiogenic stimuli, as well as the effect of
FKBPL
ablation in angiogenesis using mouse and zebrafish models.

Approach and Results—

FKBPL is secreted maximally by human microvascular endothelial cells and fibroblasts, and this was specifically downregulated by proangiogenic hypoxic signals, but not by the angiogenic cytokines, VEGF or IL8. FKBPL’s critical role in angiogenesis was supported by our inability to generate an
Fkbpl
knockout mouse, with embryonic lethality occurring before E8.5. However, whilst
Fkbpl
heterozygotic embryos showed some vasculature irregularities, the mice developed normally. In murine angiogenesis models, including the ex vivo aortic ring assay, in vivo sponge assay, and tumor growth assay,
Fkbpl
+/−
mice exhibited increased sprouting, enhanced vessel recruitment, and faster tumor growth, respectively, supporting the antiangiogenic function of FKBPL. In zebrafish, knockdown of zFkbpl using morpholinos disrupted the vasculature, and the phenotype was rescued with h
FKBPL
. Interestingly, this vessel disruption was ineffective when
zcd44
was knocked-down, supporting the dependency of zFkbpl on zCd44 in zebrafish.

Conclusions—

FKBPL is an important regulator of angiogenesis, having an essential role in murine and zebrafish blood vessel development. Mouse models of angiogenesis demonstrated a proangiogenic phenotype in
Fkbpl
heterozygotes.
Emerging Mega-FTAs: Rationale, Challenges, and Implications
Authors: Chia Siow Yue
Published: March 2015

This paper examines the recent emergence of mega–free trade agreements, namely, the Asian-centric Regional Comprehensive Economic Partnership, the Trans-Pacific Partnership, and the Trans-Atlantic Trade and Investment Partnership. In a comparative context it discusses the rationale for their emergence; their distinctive membership features, objectives, and negotiating agendas; their quantifiable benefits and dissenting voices; issues and challenges; and likely outcomes. Aspirations for “high standards” are unlikely to be met because their negotiating timelines are repeatedly missed as negotiators struggle with political, diplomatic, commercial, economic, regulatory, and technical issues. Although negotiations appear relatively simple at the outset, their complex and daunting hurdles will ultimately limit their impact on the world trading system.
Location Proximity and Productivity Spillovers: The Case of Korean Manufacturing Plants
Authors: Song Backhoon
Published: March 2015

Knowledge spillovers have been recognized as an important source of innovation and economic growth in both industry and firm-level data. A firm may reap benefits by locating near other firms in the same geographical region. In this paper, we examine how physical proximity influences a firm's future productivity and its survival possibility. Our results indicate that a firm located in a region with a higher median total factor productivity (TFP) gains higher productivity from other firms in the same region. One possible explanation is that such a firm has more opportunity to access superior external knowledge and to produce more new ideas. Our results also indicate these productivity-enhancing characteristics do not seem to be industry-specific. Finally, we find that high productivity firms are the only significant sources of knowledge spillovers, suggesting that firms benefit most from combining their internal knowledge with the external knowledge of neighboring firms with high TFP on average.
Monetary Policy and Structural Decline: Lessons from Japan for the European Crisis
Authors: Schnabl Gunther
Published: March 2015

Japan experienced a boom-and-bust cycle in the real estate and stock markets almost 20 years earlier than Europe. Since the bursting of the Japanese bubble economy, the country has fallen into a deep recession and has experimented with crisis therapies in the form of unconventional monetary expansion, Keynesian fiscal stimulus, and recapitalization of financial institutions. Japan reached a low interest rate environment in the mid 1990s and has accumulated an exceptionally high level of public debt during more than two decades of economic stagnation. This paper compares the boom-and-bust cycles in Japan and Europe with respect to the reasons for excessive booms, the characteristics of the crises, and the (potential) effects of the crisis therapies. It is argued that in both Japan and Europe the consequences of expansionary monetary and fiscal policies include the hysteresis of a low-interest rate and high government debt environment, the erosion of the allocation and signaling functions of the interest rate, the gradual quasi-nationalization of financial institutions, as well as gradual real income losses. The economic policy implication for Europe and Japan is the timely exit from crisis therapies in the form of excessively expansionary monetary and fiscal policies.