bluuebunny/crossref_metadata_2025 huggingface dataset:
Sources of uncertainties in 21st century projections of potential ocean ecosystem stressors
Authors: Frölicher Thomas L. , Rodgers Keith B. , Stock Charles A. , Cheung William W. L.
Published: August 2016

Future projections of potential ocean ecosystem stressors, such as acidification, warming, deoxygenation, and changes in ocean productivity, are uncertain due to incomplete understanding of fundamental processes, internal climate variability, and divergent carbon emission scenarios. This complicates climate change impact assessments. We evaluate the relative importance of these uncertainty sources in projections of potential stressors as a function of projection lead time and spatial scale. Internally generated climate variability is the dominant source of uncertainty in middle‐to‐low latitudes and in most coastal large marine ecosystems over the next few decades, suggesting irreducible uncertainty inherent in these short projections. Uncertainty in projections of century‐scale global sea surface temperature (SST), global thermocline oxygen, and regional surface pH is dominated by scenario uncertainty, highlighting the critical importance of policy decisions on carbon emissions. In contrast, uncertainty in century‐scale projections of net primary productivity, low‐oxygen waters, and Southern Ocean SST is dominated by model uncertainty, underscoring that the importance of overcoming deficiencies in scientific understanding and improved process representation in Earth system models are critical for making more robust projections these potential stressors. We also show that changes in the combined potential stressors emerge from the noise in 39% (34–44%) of the ocean by 2016–2035 relative to the 1986–2005 reference period and in 54% (50–60%) of the ocean by 2076–2095 following a high‐carbon emission scenario. Projected large changes in surface pH and SST can be reduced substantially and rapidly with aggressive carbon emission mitigation but only marginally for oxygen. The regional importance of model uncertainty and internal variability underscores the need for expanded and improved multimodel and large initial condition ensemble projections with Earth system models for evaluating regional marine resource impacts.
Generation of whistler waves by continuous HF heating of the upper ionosphere
Authors: Vartanyan A. , Milikh G. M. , Eliasson B. , Najmi A. C. , Parrot M. , Papadopoulos K.
Published: August 2016

Broadband VLF waves in the frequency range 7–10 kkHz and 15–19 kHz, generated by F region CW HF ionospheric heating in the absence of electrojet currents, were detected by the DEMETER satellite overflying the High Frequency Active Auroral Research Program (HAARP) transmitter during HAARP/BRIOCHE campaigns. The VLF waves are in a frequency range corresponding to the F region lower lybrid (LH) frequency and its harmonic. This paper aims to show that the VLF observations are whistler waves generated by mode conversion of LH waves that were parametrically excited by HF‐pump‐plasma interaction at the upper hybrid layer. The paper discusses the basic physics and presents a model that conjectures (1) the VLF waves observed at the LH frequency are due to the interaction of the LH waves with meter‐scale field‐aligned striations—generating whistler waves near the LH frequency; and (2) the VLF waves at twice the LH frequency are due to the interaction of two counterpropagating LH waves—generating whistler waves near the LH frequency harmonic. The model is supported by numerical simulations that show good agreement with the observations. The (Detection of Electromagnetic Emissions Transmitted from Earthquake Regions results and model discussions are complemented by the Kodiak radar, ionograms, and stimulated electromagnetic emission observations.
Experimental deformation of coarse‐grained rock salt to high strain
Authors: Linckens J. , Zulauf G. , Hammer J.
Published: August 2016

The processes and deformation mechanisms (e.g., dislocation creep, pressure solution, grain boundary sliding, and recrystallization) of rock salt are still a matter of debate. In order to fill this gap, high strain constriction experiments at 345°C, atmospheric pressure and a strain rate of ~10−7 s−1 have been conducted on natural halite cuboids (60 × 60 × 45 mm) from the Morsleben mine of Northern Germany. Most samples were almost single crystals and contain a small amount of smaller grains (10–26%). The grain boundaries are decorated with fluid inclusions. The experiments were stopped at different final strains (εy = z of ~10, 20, 30, and 40%) corresponding to a maximum strain (εx) range of 20–170%. The halite is deformed by dislocation creep, and the size of developed subgrains corresponds to the applied stress. The combined Schmid factor and subgrain boundary analysis indicate that slip was largely accommodated by the {110} < 110 > slip systems, with possible minor contribution by slip on the {100} < 110 > slip systems. Some of the deformed samples show evidence of grain boundary migration. In addition, subgrains with small misorientations form that result in large cumulative misorientations within a single grain (>40°). However, no subgrain rotation recrystallization is observed (i.e., misorientation angles are <10°). All the experiments show strain hardening, suggesting that recrystallization by grain boundary migration was not extensive and did not reset the microstructure. The experiments show that high finite strain in coarse‐grained relatively dry rock salt can be accommodated by dislocation creep, without extensive dynamic recrystallization.
Understanding Jupiter's interior
Authors: Militzer Burkhard , Soubiran François , Wahl Sean M. , Hubbard William
Published: August 2016

This article provides an overview of how models of giant planet interiors are constructed. We review measurements from past space missions that provided constraints for the interior structure of Jupiter. We discuss typical three‐layer interior models that consist of a dense central core and an inner metallic and an outer molecular hydrogen‐helium layer. These models rely heavily on experiments, analytical theory, and first‐principles computer simulations of hydrogen and helium to understand their behavior up to the extreme pressures ∼10 Mbar and temperatures ∼10,000 K. We review the various equations of state used in Jupiter models and compare them with shock wave experiments. We discuss the possibility that helium rain, core erosion, and double diffusive convection have affected the structure and evolution of giant planets. In July 2016 the Juno spacecraft entered orbit around Jupiter, promising high‐precision measurements of the gravitational field that will allow us to test our understanding of gas giant interiors better than ever before.
Constrained partitioning of autotrophic and heterotrophic respiration reduces model uncertainties of forest ecosystem carbon fluxes but not stocks
Authors: Carbone Mariah S. , Richardson Andrew D. , Chen Min , Davidson Eric A. , Hughes Holly , Savage Kathleen E. , Hollinger David Y.
Published: August 2016

We partitioned the soil carbon dioxide flux (Rs) into its respective autotrophic and heterotrophic components in a mature temperate‐boreal forest (Howland Forest in Maine, USA). We combined automated chamber measurements of Rs with two different partitioning methods: (1) a classic root trenching experiment and (2) a radiocarbon (14C) mass balance approach. With a model‐data fusion approach, we used these data to constrain a parsimonious ecosystem model (FöBAAR), and we investigated differences in modeled C fluxes and pools under both current and future climate scenarios. The trenching experiment indicated that heterotrophic respiration accounted for 53 ± 11% of total Rs. In comparison, using the 14C method, the heterotrophic contribution was 42 ± 9%. For both current and future model runs, incorporating the partitioning data as constraints substantially reduced the uncertainties of autotrophic and heterotrophic respiration fluxes. Moreover, with best fit model parameters, the two partitioning methods yielded fundamentally different estimates of the relative contributions of autotrophic and heterotrophic respiration to total Rs, especially at the annual time scale. Surprisingly, however, modeled soil C and biomass C pool size trajectories did not differ significantly between model runs based on the different methods. Instead, model differences in partitioning were compensated for by changes in C allocation, resulting in similar, but still highly uncertain, soil C pool trajectories. Our findings show that incorporating constraints on the partitioning of Rs can reduce model uncertainties of fluxes but not pools, and the results are sensitive to the partitioning method used.
A new mode of radio wave diffraction via the terrestrial surface plasmon on mountain range
Authors: Fujii Masafumi
Published: August 2016

It is shown that a new mode of radio wave diffraction occurs at the peak of mountains mediated via the terrestrial surface plasmon. If mobile electrical charges exist on the Earth's surface, the electromagnetic theory predicts strong coupling between the radio wave and the surface plasmon on the ground. If sufficient amount of electrical charges of the same sign appear on the ground as a consequence of some underground preseismic activity, they will be subject to the electrical repulsive forces. The surface electrical charges will then move toward topographic highs of nearby mountain peaks. Radio waves are then shown to interact with such electrical charges and create collective oscillations of the surface charges to induce a surface plasmon. Here it is clarified with numerical analyses on a massively parallel supercomputer that such interactions occur on the peak of mountains, hence causing peculiar phenomena of random diffraction. Depending on the density of the electrical charges on the ground surface, the interaction becomes strong enough to cause intense and random scattering and diffraction of the radio wave from the rough surface of the mountain topography. Mountain peaks thus act as a secondary source of radio waves; unexpectedly, radio waves are reradiated from the peaks into various directions by the anomalous diffraction and scattering, and the reradiated wave can propagate beyond the line of sight over mountains to reach distant locations. Such effects may arise randomly but concurrently with some preseismic activity in the crustal rocks, of which observation may allow statistical analysis of the critical state of crustal rocks over a broad area of a few hundred kilometers.
Full‐scale identification by use of self‐oscillations for overactuated marine surface vehicles
Authors: Mišković Nikola , Nađ Ðula , Vukić Zoran
Published: August 2016

Controller tuning and state estimation both benefit from knowledge about the dynamic parameters of the marine vessel. However, identifying these parameters can be a daunting task requiring precise open‐loop measurements or collection of many output data samples induced by persistently exciting inputs. Performing these experiments in real‐life conditions, every time payload of the vehicle changes, can be troublesome. Additional problems appear if the vessel is overactuated. This paper focuses on thruster modelling, actuator allocation and dynamic model identification for an overactuated marine vehicle. Firstly, we demonstrate a practical approach to mapping thrusters of an overactuated marine vehicle that in practice can generate different thrusts at identical inputs. Secondly, we address the issue of inverse actuator allocation for an overactuated surface marine platform and demonstrate a daisy‐chain approach for achieving proper thrust distribution during simultaneous motion in all controllable degrees of freedom (DoF). Finally, we describe the application of a robust identification by use of self‐oscillations (IS‐O) method to identify actuated DoF. While previous work focused on using IS‐O for identifying yaw DoF of a rudder‐actuated autonomous catamaran and thruster‐actuated micro‐remotely operated underwater vehicle, in this paper, we extend the approach to identifying surge and sway DoF. This closed‐loop identification procedure requires one experiment with four to five oscillations to completely identify inertial and nonlinear drag parameters of a marine vessel. Surge, sway and yaw DoFs of an overactuated autonomous surface marine vehicle PlaDyPos (developed at the Laboratory for Underwater Systems and Technologies) were identified using the IS‐O method during sea trials in real‐life conditions. Multiple experiments with varying initial settings were performed showing reproducibility of the identification procedure. Comparison of the results with the ordinary least squares identification procedure shows that root mean square error increase is negligible, especially if simplicity (explicit formulae for calculation of unknown parameters) and time parsimony of the IS‐O method are taken into account. © 2016 The Authors. International Journal of Adaptive Control and Signal Processing Published by John Wiley & Sons, Ltd.
Method for Characterization of Solvents for Physical Absorption Processes
Authors: Deschermeier Regina , Rehfeldt Sebastian , Klein Harald
Published: August 2016

A method for solvent screening and searching for additives in the field of physical absorption processes is presented. A model based on the concept of virtual components and on the concept of a simplified abstract flow sheet is created. An estimation procedure for thermodynamically consistent property sets for the virtual component is developed. The model is implemented into MATLAB®. Its application is demonstrated in two studies including a study for a solvent additive. Potential candidates can be characterized and ranges for properties of the solvent or additive are found by means of the model. Conclusions obtained from the model support the screening process by a reduction of the number of further investigated components.
64CuS‐labeled nanoparticles: a new sentinel‐lymph‐node‐mapping agent for PET–CT and photoacoustic tomography
Authors: Liu Qiufang , Zhou Min , Li Panli , Ku Geng , Huang Gang , Li Chun , Song Shaoli
Published: August 2016

Determining sentinel lymph node (SLN) status is critical to cancer staging and treatment decisions. Currently, in clinical practice, 99mTc‐radiocolloid‐mediated planar scintigraphy and single‐photon emission computed tomography (SPECT) are used to guide the biopsy and resection of SLNs. Recently, an emerging technique that combines positron emission tomography (PET) and photoacoustic tomography (PAT; PET–PAT) may offer accurate information in detecting SLNs. Herein, we report a kind of 64CuS‐labeled nanoparticle (64CuS‐NP) for the detection of SLNs with PET–PAT. We subcutaneously injected 64CuS‐NPs into the rats’ forepaw pads. After 24 h, the rats’ first draining axillary lymph nodes (i.e. the SLNs) could be clearly visualized with micro‐PET (μPET)–CT. Rats were sacrificed after μPET–CT imaging, their axillary lymph nodes were surgically identified, and then PAT was employed to discover 64CuS‐NP‐avid SLNs, which were embedded inside tissues. Biodistribution, autoradiography, and copper staining analyses confirmed the SLNs’ high uptake of 64CuS‐NPs. Our study indicates that 64CuS‐NPs are a promising dual‐function agent for both PET–CT and PAT and could be used with multi‐modal imaging strategies such as PET–PAT to identify SLNs in a clinical setting. Copyright © 2016 John Wiley & Sons, Ltd.
Nodular fasciitis: A frequent diagnostic pitfall on fine‐needle aspiration
Authors: Allison Derek B. , Wakely Paul E. , Siddiqui Momin T. , Ali Syed Z.
Published: August 2016

BACKGROUND

Nodular fasciitis (NF) is a benign, self‐limited, fibroblastic/myofibroblastic proliferation that is diagnostically challenging, often mimicking a malignant process due to its rapid growth clinically and its high cellularity, mitotic activity, and variable/nonspecific cytomorphologic findings. Herein, the authors report what to their knowledge is the largest and first multi‐institutional study of the cytomorphologic characteristics of NF by fine‐needle aspiration (FNA).

METHODS

The pathology archives at The Johns Hopkins Hospital, The Ohio State University Wexner Medical Center, and Emory University Hospital were searched for soft tissue FNA cytology specimens of masses confirmed to be NF. The clinical history, actual FNA diagnosis, and cytomorphologic features were recorded by the authors.

RESULTS

A total of 34 patients were identified, 33 of which had material available for review. The mean age of the patients was 40 years (range, 1‐80 years); 18 patients (52.9%) were male. The mean duration of symptoms was 3.75 months. Four cases (11.8%) and 2 cases (5.9%) were signed out as NF and “malignant neoplasm, NOS [not otherwise specified],” respectively. On average, cases were hypercellular (mean, 3.27/4). Thirty cases (90.9%) contained spindled morphology, whereas 30 cases (90.9%) and 28 cases (84.4%) contained cells with unipolar and curved cytoplasmic tails, respectively. Eccentric, ovoid, and spindled/elongated nuclei were observed in 31 cases (93.9%), 30 cases (90.9%), and 29 cases (87.9%), respectively. Nineteen cases (57.6%) lacked atypia.

CONCLUSIONS

In the current study, the diagnosis of NF was suggested in nearly 40% of cases. Combining the clinical presentation with the most commonly described cytomorphologic features will appropriately triage the majority of cases, although uncertainty will remain in a significant number of cases. Cancer Cytopathol 2017;125:20‐29. © 2016 American Cancer Society.
Creation of an idealized nasopharynx geometry for accurate computational fluid dynamics simulations of nasal airflow in patient‐specific models lacking the nasopharynx anatomy
Authors: A.T. Borojeni Azadeh , Frank‐Ito Dennis O. , Kimbell Julia S. , Rhee John S. , Garcia Guilherme J.M.
Published: August 2016

Virtual surgery planning based on computational fluid dynamics (CFD) simulations has the potential to improve surgical outcomes for nasal airway obstruction patients, but the benefits of virtual surgery planning must outweigh the risks of radiation exposure. Cone beam computed tomography (CT) scans represent an attractive imaging modality for virtual surgery planning due to lower costs and lower radiation exposures compared with conventional CT scans. However, to minimize the radiation exposure, the cone beam CT sinusitis protocol sometimes images only the nasal cavity, excluding the nasopharynx. The goal of this study was to develop an idealized nasopharynx geometry for accurate representation of outlet boundary conditions when the nasopharynx geometry is unavailable. Anatomically accurate models of the nasopharynx created from 30 CT scans were intersected with planes rotated at different angles to obtain an average geometry. Cross sections of the idealized nasopharynx were approximated as ellipses with cross‐sectional areas and aspect ratios equal to the average in the actual patient‐specific models. CFD simulations were performed to investigate whether nasal airflow patterns were affected when the CT‐based nasopharynx was replaced by the idealized nasopharynx in 10 nasal airway obstruction patients. Despite the simple form of the idealized geometry, all biophysical variables (nasal resistance, airflow rate, and heat fluxes) were very similar in the idealized vs patient‐specific models. The results confirmed the expectation that the nasopharynx geometry has a minimal effect in the nasal airflow patterns during inspiration. The idealized nasopharynx geometry will be useful in future CFD studies of nasal airflow based on medical images that exclude the nasopharynx.
Local adaptation to temperature in populations and clonal lineages of the Irish potato famine pathogenPhytophthora infestans
Authors: Mariette Nicolas , Androdias Annabelle , Mabon Romain , Corbière Roselyne , Marquer Bruno , Montarry Josselin , Andrivon Didier
Published: August 2016

Environmental factors such as temperature strongly impact microbial communities. In the current context of global warming, it is therefore crucial to understand the effects of these factors on human, animal, or plant pathogens. Here, we used a common‐garden experiment to analyze the thermal responses of three life‐history traits (latent period, lesion growth, spore number) in isolates of the potato late blight pathogenPhytophthora infestansfrom different climatic zones. We also used a fitness index (FI) aggregating these traits into a single parameter. The experiments revealed patterns of local adaptation to temperature for several traits and for theFI, both between populations and within clonal lineages. Local adaptation to temperature could result from selection for increased survival between epidemics, when isolates are exposed to more extreme climatic conditions than during epidemics. We also showed different thermal responses among two clonal lineages sympatric in western Europe, with lower performances of lineage 13_A2 compared to 6_A1, especially at low temperatures. These data therefore stress the importance of thermal adaptation in a widespread, invasive pathogen, where adaptation is usually considered almost exclusively with respect to host plants. This must now be taken into account to explain, and possibly predict, the global distribution of specific lineages and their epidemic potential.
Au Nanospikes as a Non‐enzymatic Glucose Sensor: Exploring Morphological Changes with the Elaborated Chronoamperometric Method
Authors: Coyle Victoria E. , Kandjani Ahmad Esmaielzadeh , Sabri Ylias M. , Bhargava Suresh K.
Published: August 2016

There is a continuous increasing demand for more sensitive and selective non‐enzymatic glucose sensor applications ranging from medical diagnostics to food quality assurance. Here, we deposited gold nanostructures (referred to as Au nanospikes) on Au thin‐film substrates under different electrodeposition conditions in order to determine the optimal growth parameters to obtain an enhanced glucose sensor. A modified chronoamperometric technique was employed to determine the glucose electrooxidation and sensing capabilities of the developed Au nanospikes toward 20 µM—10 mM glucose concentrations. The sensing method used here allowed for accurate determination of glucose concentrations whilst providing reproducible and stable response profiles. The sensor produced a low detection limit of 20 µM, a very high sensitivity of 201 µA mM−1 ⋅ cm−2 compared to 16.19 µA mM−1 ⋅ cm−2 for the unmodified Au substrate. The sensor also showed good selectivity when analysed against common physiological contaminants that usually interfere with conventional sensors.
Sealant behavior of gasketed segmental tunnel lining – Conceptual model
Authors: Shalabi Faisal I. , Cording Edward J. , Paul Stanley L.
Published: August 2016

Gasket sealant behavior along joints of concrete tunnel lining depends on gasket‐gasket and gasket‐groove contact loads, bonding between gasket and groove, and gasket lateral extrusion. As the gaskets are made of polymers, gasket contact loads are expected to drop with time due to relaxation. Reduction in the contact load with time is expected to affect the gasket sealant capacity. Gasket‐gasket contact loads depend on many factors such as: stiffness of the gasket material, gasket shape and volume, groove size and configuration, gasket base configuration, and the amount of gasket compression. In this work, the mechanical and sealant behavior of gaskets in grooves were investigated. Two types of gaskets were considered: open base gasket for low design water pressure (less than 600 kPa), and closed base gasket for high water pressure (up to 4###, 000 kPa). The work focused on gasket‐in‐groove load deformation behavior and gasket sealant potential including the effect of gasket contact loads, relaxation, extrusion, and the change in joint gap during water pressurization. The effect of gasket base conditions (fingers base vs. closed base) on the gasket sealant behavior was also considered in this work. A conceptual model was developed that explains the leakage of the gasket as water pressure is applied.
Asia Transition Box and Conventionally Excavated Twin Tunnels for the Istanbul Strait Road Crossing Project
Authors: Gokce Hasan Burak , Demir Korhan , Bakir Aydın , Aribilginc Tamer , Arioglu Ergin
Published: August 2016

The 14.6 km long Istanbul Strait Road Crossing Project is a safe, quick and environmentally responsible alternative road link between Asia and Europe, as such it is being constructed under a Build‐Operate‐Transfer contract by a public‐private partnership. The investor/contractor has committed to build the Project in 55 months and to operate the facility for a concession period of approximately 25 years. This article examines the project's two critical structures located in the Asian side of Istanbul, considering site investigation, construction and monitoring. The first structure is a cut and cover construction next to the Bosphorus, called the Asia Transition Box (ATB), which enabled the launching of the TBM and conventional tunnels. The second is the conventionally excavated twin tunnels (CETT), which pass under a highly urbanized part of Istanbul and provide the transition from the highway into the tunnel under the Bosphorus.
An Improvement to the Waterfront Advance–Time Relation for Irrigation Borders
Authors: Parhi Prabeer Kumar
Published: August 2016

Using the Kostiakov, modified Kostiakov and improved modified Kostiakov infiltration models, three alternate solutions of the Philip and Farrel equation are suggested for the determination of waterfront advance–time relations for irrigation borders. To test the solutions with field data of waterfront advance–time relations, each accumulated infiltration–time relation was used in the Philip and Farrel equation and the waterfront advance–time relation was determined using six observed data sets on irrigation borders. The results show that the improved modified Kostiakov model performed best in prediction of accumulated infiltration time as well as the waterfront advance–time relation as compared with the modified Kostiakov and Kostiakov infiltration model. Also, the modified Kostiakov infiltration model performed better in prediction of the infiltration and advance–time relation as compared to Kostiakov. Hence this paper suggests the use of the improved modified Kostiakov infiltration model in the Philip and Farrel equation with the help of computer programs to determine the waterfront advance–time relation in irrigation borders most accurately, as compared to the modified Kostiakov and Kostiakov infiltration models. Copyright © 2016 John Wiley & Sons, Ltd.
Design, Synthesis, and Characterization of Some Newbis‐thiazoles
Authors: Gomha Sobhi M. , Farghaly Thoraya A. , Sayed Abdelwahed R.
Published: August 2016

The essential idea of the work in this article is mainly dependent on the use ofbis‐hydrazonoyl halides for heterocyclic synthesis. The present work describes preparation and characterization of newbis‐thiazoles from reaction ofbis‐hydrazonoyl chlorides with thiosemicarbazones. The synthetic Schemes for the final compounds are proposed and discussed. Structures of the final products were elucidated by elemental analyses and Fourier transform infrared, mass spectrometry,1H, and13C‐NMR spectra.
Pseudo Multicomponent Reaction: Synthesis of Fused Pyrano Biscoumarin Analogs from 1,2‐diols
Authors: Jagadishbabu Narasashetty , Shivashankar Kalegowda
Published: August 2016

A simple and efficient method has been developed for the synthesis of fused pyrano biscoumarins using lead tetraacetate as an oxidizing agent by the condensation of one equivalent of 1,2‐diols and four equivalent of 4‐hydroxy coumarin in acetonitrile as solvent at 80°C with good to excellent yields.
Synthesis of Extended 1,3,4‐Oxadiazole and 1,3,4‐Thiadiazole Derivatives in the Suzuki Cross‐coupling Reactions
Authors: Wróblowska Monika , Kudelko Agnieszka , Kuźnik Nikodem , Łaba Katarzyna , Łapkowski Mieczysław
Published: August 2016

New derivatives of 1,3,4‐oxadiazole and 1,3,4‐thiadiazole were synthesized by a palladium catalyzed Suzuki cross‐coupling reaction under the conditions of the phase transfer catalysis. The structure of the products, the absorption and emission spectra were also studied.
Alternative modelling approaches for the ENSO time series: persistence and seasonality
Authors: Gil‐Alana Luis A.
Published: August 2016

In this article, we presented a variety of modelling approaches for the El Niño Southern Oscillation (ENSO) time series data trying to capture two features that are present in the data, in particular the persistence and the seasonal structure. For this purpose, we use long memory models based on fractional integration. The results indicate that the four ENSO series examined (El Niño 1–2; El Niño 3, El Niño 4 and El Niño 3.4) can be described in terms of a seasonal I(d) model with an order of integration higher than 0 and smaller than 1 in all four cases. The lowest degree of persistence is found in the series corresponding to El Niño 1.2, with an order of seasonal integration of 0.39. This seasonal fractional differencing parameter, however, is found to be higher than 0.5 (and thus non‐stationary) for the remaining three series.
Climate change scenarios of convective and large‐scale precipitation in the Czech Republic based on EURO‐CORDEX data
Authors: Rulfová Zuzana , Beranová Romana , Kyselý Jan
Published: August 2016

There is growing evidence that the hydrological cycle is affected by climate change. Many studies have dealt with evaluation of precipitation characteristics in regional climate models (RCMs) and their projected changes. However, little attention has been given to possible differences between scenarios of convective and stratiform precipitation and changes in their proportions on total amounts, although climate models simulate convective (subgrid) and stratiform (large‐scale) precipitation separately through deep (precipitating) convection and large‐scale precipitation parameterizations. In this study, we analyse outputs of four RCMs (CCLM, HIRHAM, RACMO2, and RCA4) from the EURO‐CORDEX project. The RCM simulations for 1989–2008 driven by ERA‐Interim reanalysis with two horizontal resolutions (0.44° and 0.11°) are evaluated against observed data in Central Europe, and projected changes of precipitation characteristics (2071–2100 vs 1971–2000) simulated by the RCMs with 0.11° horizontal resolution driven by the EC‐EARTH global climate model are then examined. We find that mean convective and large‐scale precipitation amounts tend to increase in all seasons except summer when large‐scale precipitation amounts decrease. Extreme precipitation is projected to increase in the late 21st century time slice for both convective and large‐scale precipitation. The changes of precipitation characteristics are more pronounced in simulations driven by the RCP8.5 scenario, with a larger increase of temperature, and these changes are larger for precipitation with higher intensity. Increasing proportion of convective precipitation in summer and generally increasing intensity of precipitation may have important consequences, e.g. for soil erosion, replenishment of soil moisture, and occurrence of flash floods and droughts.
Universal meshes for smooth surfaces with no boundary in three dimensions
Authors: Kabaria Hardik , Lew Adrian J.
Published: August 2016

We introduce a method to mesh the boundary Γ of a smooth, open domain in
immersed in a mesh of tetrahedra. The mesh follows by mapping a specific collection of triangular faces in the mesh to Γ. Two types of surface meshes follow: (a) a mesh that exactly meshes Γ, and (b) meshes that approximate Γ to any order, by interpolating the map over the selected faces; that is, an isoparametric approximation to Γ. The map we use to deform the faces is the closest point projection to Γ. We formulate conditions for the closest point projection to define a homeomorphism between each face and its image. These are conditions on some of the tetrahedra intersected by the boundary, and they essentially state that each such tetrahedron should (a) have a small enough diameter, and (b) have two of its dihedral angles be acute. We provide explicit upper bounds on the mesh size, and these can be computed on the fly.

We showcase the quality of the resulting meshes with several numerical examples. More importantly, all surfaces in these examples were meshed with a single background mesh. This is an important feature for problems in which the geometry evolves or changes, because it could be possible for the background mesh to never change as the geometry does. In this case, the background mesh would be a universal mesh for all these geometries. We expect the method introduced here to be the basis for the construction of universal meshes for domains in three dimensions. Copyright © 2016 John Wiley & Sons, Ltd.
Coupled FE–BE method for eigenvalue analysis of elastic structures submerged in an infinite fluid domain
Authors: Zheng C. J. , Zhang C. , Bi C. X. , Gao H. F. , Du L. , Chen H. B.
Published: August 2016

For thin elastic structures submerged in heavy fluid, e.g., water, a strong interaction between the structural domain and the fluid domain occurs and significantly alters the eigenfrequencies. Therefore, the eigenanalysis of the fluid–structure interaction system is necessary. In this paper, a coupled finite element and boundary element (FE–BE) method is developed for the numerical eigenanalysis of the fluid–structure interaction problems. The structure is modeled by the finite element method. The compressibility of the fluid is taken into consideration, and hence the Helmholtz equation is employed as the governing equation and solved by the boundary element method (BEM). The resulting nonlinear eigenvalue problem is converted into a small linear one by applying a contour integral method. Adequate modifications are suggested to improve the efficiency of the contour integral method and avoid missing the eigenvalues of interest. The Burton–Miller formulation is applied to tackle the fictitious eigenfrequency problem of the BEM, and the optimal choice of its coupling parameter is investigated for the coupled FE–BE method. Numerical examples are given and discussed to demonstrate the effectiveness and accuracy of the developed FE–BE method. Copyright © 2016 John Wiley & Sons, Ltd.
Electro‐conductive fabrics based on dip coating of cotton in poly(3‐hexylthiophene)
Authors: Cohen David Nofar , David Yaniv , Katz Nathaniel , Milanovich Michael , Anavi Daniel , Buzhor Marina , Amir Elizabeth
Published: August 2016

Electro‐conductive cotton fabrics based on poly(3‐hexylthiophene) (P3HT) were prepared using dip coating processing technique. The effect of solvent type used for the preparation of P3HT solutions on the amount of polymer incorporated into the fabric and the morphology of P3HT coated cotton fabrics were studied using Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). Thermal and mechanical studies revealed that after incorporation of P3HT, the fabrics preserved their original thermal stability and mechanical properties. Electrical resistivity measurements showed a decrease by several orders of magnitude in both surface and volume resistivities for cotton‐P3HT system relative to the untreated cotton. We also demonstrate that further significant improvement in electrical resistivity can be achieved by doping P3HT coated cotton with iodine. Copyright © 2016 John Wiley & Sons, Ltd.
Leakage in nasal high‐frequency oscillatory ventilation improves carbon dioxide clearance—A bench study
Authors: Klotz Daniel , Schaefer Christoph , Stavropoulou Dimitra , Fuchs Hans , Schumann Stefan
Published: August 2016

Objective: Nasal high frequency oscillatory ventilation (nHFOV) is a promising mode of non‐invasive neonatal respiratory support. To combine the effects of nasal continuous positive airway pressure (nCPAP) and high frequency oscillatory ventilation, an oscillatory pressure waveform is superposed to a nCPAP via a nasal or nasopharyngeal interface. nHFOV has been described to facilitate carbon dioxide (CO2) elimination compared to nCPAP. The influence of unintended leakage on CO2 elimination has not been investigated in nHFOV before. We explored the effects of oral leakage on CO2 elimination during nHFOV in a physical model of the neonatal respiratory system. Methods: A neonatal ventilator was connected to an airway‐ and lung model using binasal prongs as interface. The model comprised a continuous CO2 influx. Alveolar CO2 partial pressure was continuously measured. Gas flow rates and pressures were measured simultaneously at the prongs, pharynx, lung, and at the leakage. Effects of combined nasopharyngeal leakage (0, 5, or 10 L/min) on CO2 elimination, gas flow rate and pressure were determined at various ventilation frequencies (6, 8, 10, and 12 Hz) and amplitudes (10%, 20%, and 30% of maximum ventilator performance) at a mean airway pressure of 10 cmH2O. Results: nHFOV with moderate leakage was more effective in CO2 elimination than without leakage (P < 0.001) for all tested amplitudes and frequencies. Maximum leakage resulted in highly variable, partly ineffective CO2 elimination. Conclusions: A moderate oral leakage rather improves than impairs gas exchange during non‐invasive ventilatory support with nHFOV. Pediatr Pulmonol. 2017;52:367–372. © 2016 Wiley Periodicals, Inc.
Trimmed means for symptom trials with dropouts
Authors: Permutt Thomas , Li Feng
Published: August 2016

Dropouts from randomized trials, often for lack of efficacy or toxicity, have usually been handled as 'missing data'. We suggest that they are instead complete observations, just not numeric ones. We propose an exact test of the hypothesis of no drug effect, taking all randomized patients into account, based on a readily interpretable statistic. The method also copes with a drug that is toxic in some patients but beneficial to others, a difficult problem for standard methods. A robust conclusion of efficacy can be drawn with no assumptions other than randomization. Published 2016. This article is a U.S. Government work and is in the public domain in the USA
Routine high‐precision analysis of triple water‐isotope ratios using cavity ring‐down spectroscopy
Authors: Schauer Andrew J. , Schoenemann Spruce W. , Steig Eric J.
Published: August 2016

Rationale

Water isotope analysis for δ2H and δ18O values via laser spectroscopy is routine for many laboratories. While recent work has added the δ17O value to the high‐precision suite, it does not follow that researchers will routinely obtain high precision 17O excess (Δ17O). We demonstrate the routine acquisition of high‐precision δ2H, δ17O, δ18O, d, and Δ17O values using a commercially available laser spectroscopy instrument.

Methods

We use a Picarro L2140‐i cavity ring‐down spectroscopy analyzer with discrete liquid injections into an A0211 vaporization module by a Leap Technologies LC PAL autosampler. The instrument is run in two modes: (1) as recommended by the manufacturer (default mode) and (2) after modifying select default settings and using alternative data types (advanced mode). Reference waters analyzed over the course of 15 months while running unknown samples are used to assess system performance.

Results

The default mode provides precision for δ2H, δ17O, δ18O, d, and Δ17O values that may be sufficient for many applications. When using the advanced mode, we reach a higher level of precision for δ2H, δ17O, δ18O, d, and Δ17O values (0.4 mUr, 0.04 mUr, 0.07 mUr, 0.5 mUr, and 8 μUr, respectively, where mUr = 0.001 = ‰, and μUr = 10–6) in a shorter amount of time and with fewer syringe actuations than in the default mode. The improved performance results from an increase in the total integration time for each injected water pulse.

Conclusions

Our recommended approach for routine δ2H, δ17O, δ18O, d and Δ17O measurements with the Picarro L2140‐i is to make use of conditioning vials, use fewer injections (5 per vial) with greater pulse duration (520 seconds (s) per injection) and use only the first 120 s for δ2H measurements and all 520 s for δ17O and δ18O measurements. Although the sample throughput is 10 unknowns per day, our optimal approach reduces the number of syringe actuations, the effect of memory, and the total analysis time, while improving precision relative to the default approach. Copyright © 2016 John Wiley & Sons, Ltd.
Community software for challenging isotope analysis: First applications of ‘Easotope’ to clumped isotopes
Authors: John Cédric M. , Bowen Devon
Published: August 2016

Rationale

The measurement of complex isotope systems, notably the multiply substituted isotopologues of CO2 derived from carbonates, is challenging from a mass spectrometric point of view, but it is also time consuming and difficult from a data reduction and normalization perspective. Dedicated software often lags behind and currently limits fast, reliable and reproducible data analysis and inter‐laboratory reproducibility.

Methods

We have developed new community software ‘Easotope’ using Java and the Eclipse framework. The objectives were to reduce and normalize complex isotopic data easily using a program that could run on multiple platforms, with a central database to store data and constants, an open architecture giving end users a complete view of the data processing steps, and a permissions system allowing the administrator to empower each user in proportion to their expertise.

Results

Easotope is now freely available to download, and comprises both a server and a client executable. The server can be run either on a remote machine accessible via the internet, or on a localhost. The client allows users to access the server, and to enter and manipulate data. Easotope currently supports full data storage, data processing and data normalization for bulk isotopes of carbon and oxygen, and for clumped isotopes.

Conclusions

Easotope greatly simplifies data processing, reducing processing time to less than a second compared with 30 min when done manually. The software also ensures consistency in data reduction and normalization both within a laboratory and between laboratories. Easotope is designed with the ability to implement other isotopic systems in the future. Copyright © 2016 John Wiley & Sons, Ltd.
Consensus estimation‐based target localization in underwater acoustic sensor networks
Authors: Yan Jing , Xu Ziqiang , Wan Yan , Chen Cailian , Luo Xiaoyuan
Published: August 2016

Target localization, which aims to estimate the location of an unknown target, is one of the key issues in applications of underwater acoustic sensor networks (UASNs). However, the resource‐constrained property of an underwater environment such as noise makes target localization a challenging problem. This paper considers a consensus estimation‐based approach to the target localization problem in UASNs. To detect and acquire the position of the target, a hybrid architecture is applied to UASNs, where autonomous underwater vehicles provide self‐location and clock synchronization for sensor nodes. Built on this architecture, a trilateration method coupled with a regional optimal solution is provided to estimate the rough localization of a target. Furthermore, a consensus estimation‐based algorithm is designed for the regional optimal solution, such that localization accuracy is improved. In the presence of measurement and communication noises, localization error and asymptotic unbiasedness for the estimation algorithm are also investigated. Finally, simulation results show that the proposed localization approach can avoid the occurrence of no‐solution while improving the localization accuracy. In addition, the hybrid communication architecture can reduce the number of transmissions compared with egalitarian decentralized networks. Copyright © 2016 John Wiley & Sons, Ltd.
Group‐oriented encryption for dynamic groups with constant rekeying cost
Authors: Nishat Koti , Purushothama B. R.
Published: August 2016

In group‐oriented encryption, a sender encrypts a message and sends it to a set of users, which form a group. Encryption is carried out using the group's public key. Only the legitimate group users are capable of decrypting the ciphertext using their individual private keys. Existing literature in group‐oriented encryption schemes considers only static groups in secure group communication. Extension of the existing schemes to support dynamic groups results in the one‐affects‐all problem. We propose a group‐oriented encryption scheme which is capable of handling dynamic groups in secure group communication. In the proposed scheme, we consider groups which are dynamic in nature and involve joining and leaving of members thereby giving rise to the problem of forward and backward secrecy for which group public key needs to be changed. In the proposed scheme, updating the group public key does not affect the group users, and they are not required to update any of their secret key components. The group members can continue their operations with the same secret keys which they are possessing since the time they joined the group. Also, size of the secret key at users, the public key and the ciphertext, remains constant. Copyright © 2016 John Wiley & Sons, Ltd.
A group key‐policy attribute‐based encryption with partial outsourcing decryption in wireless sensor networks
Authors: Wang Qihua , Yu Chang Wu , Li Fagen , Wang Huaqun , Cao Lijie
Published: August 2016

Outsourcing decryption that enables the authorized users to obtain the original data without decryption computation is crucially important for wireless sensor networks in public data center. The existing outsourcing decryption schemes have been designed based on key‐policy attribute‐based encryption. The security of outsourcing decryption cannot be guaranteed, because the data center is not loyal, and existing schemes have high computational complexity and energy consumption. In this work, a novel partially outsourcing decryption scheme is proposed to guarantee data security and computational efficiency for resource‐constrained sensor nodes and terminal equipments. According to the attributes of cluster nodes in the proposed scheme, the encryption secret key is encrypted based on group key‐policy attribute‐based encryption and sent to data center, and authorized users who satisfy the attributes of the ciphertext can obtain the secret key to decrypt the ciphertext. Furthermore, in order to reduce the decryption overhead for users, the authorized users can simply decrypt the transformation ciphertext that is partially decrypted by the data center using token key. Compared with the previous decryption schemes, the proposed scheme efficiently decrypts ciphertext and enhances security of the data. The simulation results also indicate that the proposed scheme is efficient in terms of energy consumption and computation by comparing to previous work. Copyright © 2016 John Wiley & Sons, Ltd.