bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stress and displacement fields in the outer wedge induced by megathrust earthquakes
Authors: Fukao Yoshio , Hori Takane , Kodaira Shuichi 
Published: April 2014

AbstractWe model plate boundary slip at the outer (oceanward) segment of the megathrust wedge as slip at the base of a two‐dimensional elastic wedge, subject to gravity force, with a sloping seafloor at the top, and drag at the bottom from a rigid plate in frictional contact. The stress and displacement fields in the wedge are given analytically as functions of basal frictional coefficient μe. Unlike either conventional dislocation models (constant slip) or crack models (constant stress drop), our wedge model (constant μe drop) does not show a stress singularity at the updip toe of the plate boundary. The slip increases, but the stress drop decreases updip along the fault toward the trench axis. There is a minimum stress difference state in the wedge when μe is varied. By referring to this state (μe = μec), the stress state is separated into a horizontally tensile regime (μe < μec) and a horizontally compressional regime (μe > μec). Slip associated with a μe drop in the range μe ≤ μec occurs toward increasing horizontal tension and shear energy. Such earthquakes include tsunami earthquakes occurring in the outer segment and the 2011 great Tohoku‐Oki earthquake, which involved both the outer and inner segments, with much larger slip in the outer segment. These earthquakes are characterized by an almost complete drop of basal stress, which brings the wedge into the maximum tensile state, leading to the rare occurrence of thrust aftershocks at the base of the wedge and frequent occurrence of normal fault aftershocks within the wedge.
Scale interaction between typhoons and the North Pacific subtropical high and associated remote effects during the Baiu/Meiyu season
Authors: Hirata Hidetaka , Kawamura Ryuichi 
Published: April 2014

AbstractThe interaction between typhoons and the North Pacific subtropical high and the associated remote impact on East Asian and North Pacific anomalous weather during the Baiu/Meiyu season have been investigated using the Japanese long‐term Reanalysis project data aided by the Japan Meteorological Agency Climate Data Assimilation System. The typhoons that appeared in July have been categorized into two primary tracks, the Hainan Island course (HC) and the Okinawa Island course (OC). A typhoon gives rise to negative absolute vorticity advection along its eastern periphery, which locally reinforces the western ridge of the North Pacific subtropical high, whereas the resultant anomalous high stimulates the westward (northward) migration of the HC (OC) typhoon through its combination with the background flow. A combined effect of the typhoon and its induced anomalous anticyclonic circulation increases the transportation of moisture into the Baiu/Meiyu frontal zone in the vicinity of Japan. Over the East China Sea and the Sea of Japan, northward or northeastward moisture flux is pronounced along the western periphery of the typhoon‐induced anticyclonic circulation anomaly in the HC category, triggering heavy rainfall on central Japan's Sea of Japan coast. Similar remote effects also operate in the OC category, which is responsible for the occurrence of extremely heavy rainfall along the Pacific coast of western Japan. When an OC typhoon approaches the Asian jet, it is capable of giving rise to anticyclonic vorticity within the jet, leading to the downstream development of stationary Rossby wave packets via the North Pacific waveguide.
Analytical solutions for two‐phase subsurface flow to a leaky fault considering vertical flow effects and fault properties
Authors: Kang Mary , Nordbotten Jan M. , Doster Florian , Celia Michael A. 
Published: April 2014

AbstractConductive faults in geologic formations can serve as leakage pathways for fluids such as CO2 and methane, which would otherwise remain trapped beneath low‐permeability layers. To estimate leakage rates and the associated pressure effects on adjacent aquifers, modeling of the flow in the vicinity of leaky faults must be performed. The flow from an aquifer to a leaky fault is controlled by aquifer properties as well as fault properties, including the fault permeability, fault width, and anisotropy in the fault permeability. Depending on aquifer properties and leakage rates, vertical flow equilibrium may not be reached in the aquifer in the vicinity of the leaky fault. Therefore, analytical solutions for leakage through faults that allow for vertical flow need to be developed. To do this, the vertically integrated form of the two‐phase flow formulation based on vertical equilibrium is expanded by assuming a linearly structured vertical flow field, and steady state analytical solutions for single‐phase and two‐phase leakage are derived. In the case of two‐phase leakage, anisotropic aquifer permeabilities are shown to produce stronger vertical flow effects than in the case of single‐phase leakage. Using numerical simulations, a model representing fault properties that is compatible with the analytical solutions is developed. The combination of the fault model and the analytical solutions captures the effects of leakage through faults with different properties and vertical flow effects. The incorporation of this fault model/analytical solution in larger basin‐wide multiscale models can enable subgrid‐scale effects due to leakage through faults to be captured with improved efficiency.
Hydraulic conductivity field characterization from the joint inversion of hydraulic heads and self‐potential data
Authors: Soueid Ahmed A. , Jardani A. , Revil A. , Dupont J. P. 
Published: April 2014

AbstractPumping tests can be used to estimate the hydraulic conductivity field from the inversion of hydraulic head data taken intrusively in a set of piezometers. Nevertheless, the inverse problem is strongly underdetermined. We propose to add more information by adding self‐potential data taken at the ground surface during pumping tests. These self‐potential data correspond to perturbations of the electrical field caused directly by the flow of the groundwater. The coupling is electrokinetic in nature that is due to the drag of the excess of electrical charges existing in the pore water. These self‐potential signals can be easily measured in field conditions with a set of the nonpolarizing electrodes installed at the ground surface. We used the adjoint‐state method for the estimation of the hydraulic conductivity field from measurements of both hydraulic heads and self potential during pumping tests. In addition, we use a recently developed petrophysical formulation of the streaming potential problem using an effective charge density of the pore water derived directly from the hydraulic conductivity. The geostatistical inverse framework is applied to five synthetic case studies with different number of wells and electrodes and thickness of the confining unit. To evaluate the benefits of incorporating the self‐potential data in the inverse problem, we compare the cases in which the data are combined or not. Incorporating the self‐potential information improves the estimate of hydraulic conductivity field in the case where the number of piezometers is limited. However, the uncertainty of the characterization of the hydraulic conductivity from the inversion of the self‐potential data is dependent on the quality of the distribution of the electrical conductivity used to solve the Poisson equation. Consequently, the approach discussed in this paper requires a precise estimate of the electrical conductivity distribution of the subsurface and requires therefore new strategies to be developed for the joint inversion of the hydraulic and electrical conductivity distributions.
General Methods for Synthesis of N‐Methyliminodiacetic Acid Boronates from Unstable ortho‐Phenolboronic Acids
Authors: Ahn Su‐Jin , Lee Chun‐Young , Cheon Cheol‐Hong 
Published: April 2014

AbstractA range of N‐methyliminodiacetic acid (MIDA) boronates of commercially available but unstable ortho‐phenolboronic acid derivatives can be readily prepared through simple condensation between the corresponding phenolboronic acids and MIDA in the presence of molecular sieves. The resulting MIDA boronates are bench‐top stable and display a remarkable stability even in DMSO solution at high temperature (>120 °C) compared with their parent boronic acids. Moreover, the utility of the resulting MIDA boronate was successfully demonstrated in a cross‐coupling reaction using the slow‐release protocol to afford the cross‐coupled product in much better yield compared with its parent boronic acid counterpart. In addition, an alternative, but more efficient, synthetic route for difficult‐to‐access ortho‐phenol MIDA boronates has been developed through the MIDA boronate formation of methoxymethyl (MOM) protected ortho‐phenolboronic acid, followed by deprotection of the MOM group with TMSCl under ambient conditions.magnified image
Synergistic Gold(I)/Trimethylsilyl Catalysis: Efficient Alkynylation of N,O‐Acetals and Related Pro‐Electrophiles
Authors: Michalska Malina , Songis Olivier , Taillier Catherine , Bew Sean P. , Dalla Vincent 
Published: April 2014

AbstractWe report a unique mechanism‐guided reaction that enhances and expands the chemical space that readily generated gold(I) acetylides currently operate in. Our strategy exploits the propensity of gold(I) carbophilic catalysts with specific counteranions (LAuX – X=triflate or triflimidate) to efficiently activate and desilylate trimethylsilylalkynes, thereby mediating the in situ formation of equal and catalytic quantities of a silyl Lewis acid (TMSX) of tunable strength and a nucleophilic gold(I) acetylide. This unprecedented manifold opens avenues for developing synergistic silyl‐gold(I)‐catalyzed alkynylation strategies of diverse pro‐electrophiles which were heretofore unattainable, the proof of concept being principally exemplified herein with the first catalytic alkynylation of N,O‐acetals. The reaction proceeds at low catalyst loading, employs mild reaction conditions, is easily scalable, and affords propargylic lactam products in good to excellent yields. Furthermore, it is fully amenable to a diverse array of structure and function substrates, and also expands to other pro‐electrophiles beyond N,O‐acetals. Control experiments have been carried out that strongly support our dual reaction mechanism proposal which, furthermore, itself outlines an inextricable link between the strength of the ancillary silyl Lewis acid (TMSOTf versus TMSNTf2) and the coordinating ability of the gold counter anion employed. This underlying feature of our system underscores its significant potential and flexibility, which indeed manifests with the demonstration that by carefully selecting the gold counter ion, it is possible to manipulate the strength of the ancillary silyl Lewis acid so that it can be tailored to the ionizing ability of a particular pro‐electrophile.magnified image
Therapeutic monitoring of amphotericin B in Saudi ICU patients using UPLC MS/MS assay
Authors: Al‐Quadeib Bushra T. , Radwan Mahasen A. , Siller Lidija , Mutch Elaine , Horrocks Ben , Wright Matthew , Alshaer Abdulaziz 
Published: April 2014

ABSTRACTAmphotericin B (AmB) is the first‐line agent for the treatment of life‐threatening invasive fungal infections. The aim of this study was to monitor AmB in critically ill Saudi patients in ICU after i.v. administration of 0.68 ± 0.1 mg/kg/day Fungizone®. A selective, sensitive and precise UPLC MS/MS method was developed to measure AmB concentrations in these patients. Seven ICU patients with creatinine clearance (ClCr) >40 mL/min were included. AmB levels were analyzed using a Waters Aquity UPLC MS/MS system, a BEH Shield RP18 column and detection via electrospray ionization source with positive ionization mode. The precision and accuracy of the developed UPLC method in the concentration range of 200–4000 ng/mL show no significant difference among inter‐ and‐intra‐day analysis (p > 0.05). Linearity was observed over the investigated range with correlation coefficient, r > 0.995 (n = 6/day). The pharmacokinetics of AmB in these patients, at steady state, showed a high terminal half‐life of 124.6 ± 73.4 h, with a highest concentration of 513.9 ± 281.1 ng/mL, a lowest concentration 316.4 ± 129.0 ng/mL and a mean clearance 91.1 ± 39.2 mL/h/kg. The pharmacokinetics of AmB in critically ill Saudi patients in ICU was studied using a fully validated assay. A weak correlation (r = −0.22) of AmB Cl with ClCr was obtained, which suggests the need for further investigation in a larger population. Copyright © 2014 John Wiley & Sons, Ltd.
A Roadmap to Uranium Ionic Liquids: Anti‐Crystal Engineering
Authors: Yaprak Damla , Spielberg Eike T. , Bäcker Tobias , Richter Mark , Mallick Bert , Klein Axel , Mudring Anja‐Verena 
Published: April 2014

AbstractIn the search for uranium‐based ionic liquids, tris(N,N‐dialkyldithiocarbamato)uranylates have been synthesized as salts of the 1‐butyl‐3‐methylimidazolium (C4mim) cation. As dithiocarbamate ligands binding to the UO22+ unit, tetra‐, penta‐, hexa‐, and heptamethylenedithiocarbamates, N,N‐diethyldithiocarbamate, N‐methyl‐N‐propyldithiocarbamate, N‐ethyl‐N‐propyldithiocarbamate, and N‐methyl‐N‐butyldithiocarbamate have been explored. X‐ray single‐crystal diffraction allowed unambiguous structural characterization of all compounds except N‐methyl‐N‐butyldithiocarbamate, which is obtained as a glassy material only. In addition, powder X‐ray diffraction as well as vibrational and UV/Vis spectroscopy, supported by computational methods, were used to characterize the products. Differential scanning calorimetry was employed to investigate the phase‐transition behavior depending on the N,N‐dialkyldithiocarbamato ligand with the aim to establish structure–property relationships regarding the ionic liquid formation capability. Compounds with the least symmetric N,N‐dialkyldithiocarbamato ligand and hence the least symmetric anions, tris(N‐methyl‐N‐propyldithiocarbamato)uranylate, tris(N‐ethyl‐N‐propyldithiocarbamato)uranylate, and tris(N‐methyl‐N‐butyldithiocarbamato)uranylate, lead to the formation of (room‐temperature) ionic liquids, which confirms that low‐symmetry ions are indeed suitable to suppress crystallization. These materials combine low melting points, stable complex formation, and hydrophobicity and are therefore excellent candidates for nuclear fuel purification and recovery.
The Bim deletion polymorphism clinical profile and its relation with tyrosine kinase inhibitor resistance in Chinese patients with non–small cell lung cancer
Authors: Zhao Mingchuan , Zhang Yishi , Cai Weijing , Li Jiayu , Zhou Fei , Cheng Ningning , Ren Ruixin , Zhao Chao , Li Xuefei , Ren Shengxiang , Zhou Caicun , Hirsch Fred R. 
Published: April 2014

BACKGROUNDEpidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are widely used for the treatment of patients with advanced non–small cell lung cancer (NSCLC) who have EGFR mutations. Recent studies have indicated that some patients with positive mutations were refractory to EGFR TKIs if they harbored a B‐cell chronic lymphocytic leukemia/lymphoma (Bcl‐2)‐like 11 (Bim) deletion polymorphism. The objective of the current work was to retrospectively study the Bim deletion polymorphism in Chinese patients with NSCLC and its correlation with the efficacy of EGFR TKIs.METHODSDistribution of the Bim polymorphism was detected using polymerase chain reaction analysis and direct sequencing of DNA from peripheral neutrophils in samples from 352 patients with NSCLC. Of the 352 patients, 166 who received TKI therapy and had an activating mutation identified were involved in further analysis. Progression‐free survival (PFS) was the primary endpoint of the subsequent analyses, and the incidence of the Bim polymorphism and its relation to clinical benefit from EGFR TKIs also were investigated.RESULTSIn total, 45 of 352 patient samples (12.8%) had the Bim deletion polymorphism, which was distributed randomly with regard to various clinical characteristics. In patients with EGFR mutations who received treatment with TKIs, the median PFS and the median objective response rate were 4.7 months and 25%, respectively, for those with the Bim deletion polymorphism versus 11 months (P = .003) and 66% (P = .001), respectively, for those with wild‐type Bim. Cox regression analysis identified Bim status (P = .016) and sex (P = .002) as independent factors predicting clinical benefit from EGFR TKIs in patients with EGFR‐mutated NSCLC.CONCLUSIONSThe incidence of the Bim deletion polymorphism was approximately 13% in this study, and it was associated with a poor clinical response to EGFR TKIs in patients who had NSCLC with EGFR mutations. Cancer 2014;120:2299–2307. © 2014 American Cancer Society.
Electrocatalytic and Simultaneous Determination of Ascorbic Acid, Nicotinamide Adenine Dinucleotide and Folic Acid at Ruthenium(II) Complex‐ZnO/CNTs Nanocomposite Modified Carbon Paste Electrode
Authors: Karimi‐Maleh Hassan , Tahernejad‐Javazmi Fahimeh , Daryanavard Marzieh , Hadadzadeh Hassan , Ensafi Ali A. , Abbasghorbani Maryam 
Published: April 2014

AbstractThis paper describes the development a novel ruthenium(II) complex‐ZnO/CNTs modified carbon paste electrode (Ru(II)/ZnO/CNTs/CPE) for the electrocatalytic determination of ascorbic acid (AA). The objective of this novel electrode modification was to seek new electrochemical performances for the detection of AA, nicotinamide adenine dinucleotide (NADH) and folic acid (FA). The peak potentials recorded were 170, 500 and 830 mV vs. Ag/AgCl/KClsat for AA, NADH and FA, respectively. The peak currents were linearly dependent on AA, NADH and FA concentrations using square wave voltammetry (SWV) method at the ranges of 0.008–251, 1.0–650, and 3.0–700 µmol L−1, with detection limits of 0.005, 0.5, and 1.0 µmol L−1, respectively.
Demographic characteristics do not decrease the utility of depressive symptoms assessments: examining the practical impact of item bias in four heterogeneous samples of older adults
Authors: Dmitrieva Natalia O. , Fyffe Denise , Mukherjee Shubhabrata , Fieo Robert , Zahodne Laura B. , Hamilton Jamie , Potter Guy G. , Manly Jennifer J. , Romero Heather R. , Mungas Dan , Gibbons Laura E. 
Published: April 2014

ObjectivePrevious studies have identified differential item function (DIF) in depressive symptoms measures, but the impact of DIF has been rarely reported. Given the critical importance of depressive symptoms assessment among older adults, we examined whether DIF due to demographic characteristics resulted in salient score changes in commonly used measures.MethodsFour longitudinal studies of cognitive aging provided a sample size of 3754 older adults and included individuals both with and without a clinical diagnosis of major depression. Each study administered at least one of the following measures: the Center for Epidemiologic Studies Depression scale (20‐item ordinal response or 10‐item dichotomous response versions), the Geriatric Depression Scale, and the Montgomery–Åsberg Depression Rating Scale. Hybrid logistic regression‐item response theory methods were used to examine the presence and impact of DIF due to age, sex, race/ethnicity, and years of education on the depressive symptoms items.ResultsAlthough statistically significant DIF due to demographic factors was present on several items, its cumulative impact on depressive symptoms scores was practically negligible.ConclusionsThe findings support substantive meaningfulness of previously reported demographic differences in depressive symptoms among older adults, showing that these individual differences were unlikely to have resulted from item bias attributable to demographic characteristics we examined. Copyright © 2014 John Wiley & Sons, Ltd.
DIFFERENCE IN DIFFERENCES FOR STAYERS WITH A TIME‐VARYING QUALIFICATION: HEALTH EXPENDITURE ELASTICITY OF THE ELDERLY
Authors: Lee Myoung‐Jae , Kim Young‐Sook 
Published: April 2014

SUMMARYIn difference in differences, a treatment is applied only to a qualified group at some time point. The qualification may be time‐constant as in gender, or time‐varying as in residential location. When the qualification is time‐varying, there appear four groups: the newly qualified (in‐movers), the already qualified (in‐stayers), the newly disqualified (out‐movers), and the already disqualified (out‐stayers). A change in qualification may affect the response variable of interest even when the treatment effect is zero, which is an ‘untreated moving effect’. Also, when the treatment effect is not zero, it may be different across the four groups. The conventional difference in differences fails to remove untreated moving effects and ignores the possible treatment effect heterogeneity across the groups. This paper shows how to account for untreated moving effects and proposes ‘the effect on in‐stayers’ as the main effect of interest. Our proposal can be implemented with least squares estimator for panel models or with nonparametric methods. An empirical analysis is provided using Korean data for the effects of the basic elder pension on health‐care expenditure. Copyright © 2014 John Wiley & Sons, Ltd.
In vitro age dependent response of macrophages to micro and nano titanium dioxide particles
Authors: Bruno Marcos E. , Sittner Maximiliano , Cabrini Rómulo L. , Guglielmotti María B. , Olmedo Daniel G. , Tasat Deborah R. 
Published: April 2014

AbstractAs a result of corrosion, microparticles (MP) and/or nanoparticles (NP) can be released from the metallic implants surface into the bioenvironment. The biological response to these particles depends not only on the physico‐chemical properties of the particles but also on host factors, such as age. Macrophages have attracted wide concern in biomedicine. The aim of this investigation was to study the age related biological response of macrophages to TiO2‐MP and NP in vitro. Alveolar macrophages (AM) obtained from young and senescent rats were cultured and exposed to TiO2‐MP and NP. Cell metabolism, superoxide anion (O2−) and nitric oxide (NO) generation, and cytokine release (IL‐6, TNFα, IL‐10) were measured. Cell metabolism was not affected by particle exposure. O2− and NO generation increased in a dose dependent manner. A marked increase on IL‐6 release was found in the young‐AM subpopulation exposed to TiO2‐MP. Conversely, both particle sizes induced a dose dependent release of TNFα in senescent‐AM. Only the highest concentration of TiO2‐particles caused a significant increase in IL‐10 release in AM‐cultures. These observations lend strong support to the suggestion that cellular response of macrophages to TiO2‐particles is age dependent. The biological effect of the particles would seem to be more deleterious in the senescent age‐group. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 471–478, 2015.