bluuebunny/crossref_metadata_2025 huggingface dataset:
Operating Envelopes for Second-Generation PFBC Combined Cycle Plants
Authors: Garland R. V. , Robertson A.
Published: March 2015

Second-generation PFBC combined cycle plants introduce additional dimensions of operational and configurational considerations over their first generation counterparts. With the capability to raise gas turbine inlet temperatures to state of the art and beyond, the second-generation systems introduce a matrix of parameters that require in-depth analysis before the plant design point can be determined. The interactions among turbine inlet temperature, turbine exhaust temperature, excess-air level, steam conditions, steam cycle participation, PFBC operating temperature, and the configuration of the heat recovery apparatus produce a myriad of possible combined-cycle plant configurations. This paper provides insight into how these parameters interact and how the correct selection of the parametric values can produce various plants of best efficiency, highest output, and simplest configuration.
Conductive-AFM topography and current maps simulator for the study of polycrystalline high-k dielectrics
Authors: Couso Carlos , Porti Marc , Martin-Martinez Javier , Iglesias Vanessa , Nafria Montserrat , Aymerich Xavier
Published: March 2015

In this work, a simulator of conductive atomic force microscopy (C-AFM) was developed to reproduce topography and current maps. In order to test the results, the authors used the simulator to investigate the influence of the C-AFM tip on topography measurements of polycrystalline high-k dielectrics, and compared the results with experimental data. The results show that this tool can produce topography images with the same morphological characteristics as the experimental samples under study. Additionally, the current at each location of the dielectric stack was calculated. The quantum mechanical transmission coefficient and tunneling current were obtained from the band diagram by applying the Airy wavefunction approach. Good agreement between experimental and simulation results indicates that the tool can be very useful for evaluating how the experimental parameters influence C-AFM measurements.
Creation of an atlas of filter positions for fluence field modulated CT
Authors: Szczykutowicz Timothy P. , Hermus James
Published: March 2015

Purpose:

Fluence field modulated CT (FFMCT) and volume of interest (VOI) CT imaging applications require adjustment of the profile of the x‐ray fluence incident on a patient as a function of view angle. Since current FFMCT prototypes can theoretically take on an infinite number of configurations, measuring a calibration data set for all possible positions would not be feasible. The present work details a methodology for calculating an atlas of configurations that will span all likely body regions, patient sizes, patient positioning, and imaging modes. The hypothesis is that there exists a finite number of unique modulator configurations that effectively span the infinite number of possible fluence profiles with minimal loss in performance.

Methods:

CT images of a head, shoulder, thorax, abdominal, wrist, and leg anatomical slices were dilated and contracted to model small, medium, and large sized patients. Additionally, the images were positioned from iso‐center by three different amounts. The modulator configurations required to compensate for each image were computed assuming a FFMCT prototype, digital beam attenuator, (DBA), was set to equalize the detector exposure. Each atlas configuration should be different from the other atlas configurations. The degree of difference was quantified using the sum of the absolute differences in filter thickness between configurations. Using this metric, a set of unique wedge configurations for which no two configurations have a metric value smaller than some threshold can be constructed. Differences in the total number of incident photons between the unconstrained filters and the atlas were studied as a function of the number of atlas positions for each anatomical site and size/off‐centering combination.

Results:

By varying the threshold used in creating the atlas, it was found that roughly 322 atlas positions provided an incident number of photons within 20% of using 19 440 unique filters (the number of atlas entries ranged from 7213 to 1). Additionally, for VOI applications implemented with a single VOI region, the number of required filter configurations was expressed in a simple closed form solution.

Conclusions:

The methodology proposed in this work will enable DBA‐FFMCT and DBA‐VOI imaging in the clinic without the need for patient specific air‐scans to be performed. In addition, the methodology proposed here is directly applicable to other modulator designs such as piecewise linear, TomoTherapy multi leaf collimators, 2D fluid arrays, and inverse geometry CT.
Self-consistent, self-coupled scalar gravity
Authors: Franklin J.
Published: March 2015

A scalar theory of gravity, extending Newtonian gravity to include field energy as its source, is developed. The physical implications of the theory are probed through its spherically symmetric (source) solutions. The aim is to demonstrate rational physical model building, together with physical and experimental checks of correctness. The theory discussed here was originally considered by Einstein prior to his introduction of general relativity.
High-field level crossing in atomic hydrogen
Authors: Lynch Kara M. , Flanagan Kieran , Stroke H. Henry
Published: March 2015

In hydrogen, an external magnetic field, which we calculate to be ≈16.65 T, cancels the internal field caused by the electron motion in the magnetic sublevels with mJ=+1/2. This results in an energy-level degeneracy between states with nuclear magnetic sublevels mI of opposite signs. The evaluation of this field has been calculated previously with the use of the low-field quantum numbers F, mF. We show that this calculation is considerably simpler in the high-field mJ, mI representation. A comparison is given with the earlier work.
The puzzle of the steady-state rotation of a reverse sprinkler
Authors: Rueckner Wolfgang
Published: March 2015

The continuous rotation of the reverse sprinkler has been a puzzle for over two decades. This article presents a series of experiments that demonstrate that a properly designed reverse sprinkler experiences no steady-state torque and does not rotate. Ignoring transients when the flow starts and stops, if any sustained rotation of the reverse sprinkler occurs, it is because a force couple produces a torque accompanied by vortex flow inside the body of the sprinkler. No steady-state rotation occurs if the vortex is suppressed or prevented from forming in the first place. Demonstrative proof is given that an ideal reverse sprinkler does not rotate.
Particle dynamics in damped nonlinear quadrupole ion traps
Authors: Vinitsky Eugene A. , Black Eric D. , Libbrecht Kenneth G.
Published: March 2015

We examine the motions of particles in quadrupole ion traps as a function of damping and trapping forces, including cases where nonlinear damping or nonlinearities in the electric field geometry play significant roles. In the absence of nonlinearities, particles are either damped to the trap center or ejected, while their addition brings about a rich spectrum of stable closed particle trajectories. In three-dimensional (3D) quadrupole traps, the extended orbits are typically confined to the trap axis, and for this case we present a 1D analysis of the relevant equation of motion. We follow this with an analysis of 2D quadrupole traps that frequently show diamond-shaped closed orbits. For both the 1D and 2D cases, we present experimental observations of the calculated trajectories in microparticle ion traps. We also report the discovery of a new collective behavior in damped 2D microparticle ion traps, where particles spontaneously assemble into a remarkable knot of overlapping, corotating diamond orbits, self-stabilized by air currents arising from the particle motion.
Einstein's perihelion formula and its generalization
Authors: D'Eliseo Maurizio M.
Published: March 2015

Einstein's perihelion advance formula can be given a geometric interpretation in terms of the curvature of the ellipse. The formula can be obtained by splitting the constant term of an auxiliary polar equation for an elliptical orbit into two parts that, when combined, lead to the expression of this relativistic effect. Using this idea, we develop a general method for dealing with orbital precession in the presence of central perturbing forces, and apply the method to the determination of the total (relativistic plus Newtonian) secular perihelion advance of the planet Mercury.
Completing the Liénard-Wiechert potentials: The origin of the delta function fields for a charged particle in hyperbolic motion
Authors: Cross Daniel J.
Published: March 2015

Calculating the electromagnetic fields of a uniformly accelerated charged particle is a surprisingly subtle problem that has been long discussed in the literature. In particular, the fields calculated from the Liénard-Wiechert potentials fail to satisfy Maxwell's equations. While the correct fields have been obtained many times and through various means, it has remained unclear why the standard approach fails. We identify and amend the faulty step in the Liénard-Wiechert construction and provide a new direct calculation of the fields and potentials for a charge in hyperbolic motion.
Draft Genome Sequences of 33 Salmonella enterica Clinical and Wildlife Isolates from Chile
Authors: Toro Magaly , Retamal Patricio , Allard Marc , Brown Eric W. , Evans Peter , Gonzalez-Escalona Narjol
Published: March 2015

Salmonella enterica
causes health problem worldwide. The relationships among strains that are from the same serotype but different hosts, countries, and continents remain elusive. Few genome sequences are available from
S. enterica
isolates from South America. Therefore, we sequenced the genomes of 33 strains from diverse sources isolated in Chile and determined that they were of different serotypes. These genomes will improve phylogenetic analysis of Salmonella strains from Chile and the rest of South America.
Complete Genome Sequence of Raoultella ornithinolytica Strain S12, a Lignin-Degrading Bacterium Isolated from Forest Soil
Authors: Bao Wenying , Zhou Yun , Jiang Jingwei , Xu Zhihui , Hou Liyuan , Leung Frederick Chi-Ching
Published: March 2015

We report the complete genome sequence of
Raoultella ornithinolytica
strain S12, isolated from a soil sample collected from areas bordering rotten wood and wet soil on Mt. Zijin, Nanjing. The complete genome of this bacterium may contribute toward the discovery of efficient lignin-degrading pathways.
Draft Genome Sequence of Thauera sp. Strain SWB20, Isolated from a Singapore Wastewater Treatment Facility Using Gel Microdroplets
Authors: Dichosa Armand E. K. , Davenport Karen W. , Li Po-E , Ahmed Sanaa A. , Daligault Hajnalka , Gleasner Cheryl D. , Kunde Yuliya , McMurry Kim , Lo Chien-Chi , Reitenga Krista G. , Daughton Ashlynn R. , Shen Xiaohong , Frietze Seth , Wang Dongping , Johnson Shannon L. , Drautz-Moses Daniela I. , Schuster Stephan , Chain Patrick S. , Han Cliff
Published: March 2015

We report here the genome sequence of Thauera sp. strain SWB20, isolated from a Singaporean wastewater treatment facility using gel microdroplets (GMDs) and single-cell genomics (SCG). This approach provided a single clonal microcolony that was sufficient to obtain a 4.9-Mbp genome assembly of an ecologically relevant Thauera species.
Complete Genome Sequence of Escherichia coli Strain BL21
Authors: Jeong Haeyoung , Kim Hyun Ju , Lee Sang Jun
Published: March 2015

Escherichia coli
strain BL21 is one of the widely used bacterial hosts for high-level recombinant protein production and for other applications. Here, we present the complete genome sequence of a commercial version of the
Escherichia coli
BL21 strain.
Draft Genome Sequence of Lactobacillus kunkeei AR114 Isolated from Honey Bee Gut
Authors: Porcellato Davide , Frantzen Cyril , Rangberg Anbjørg , Umu Ozgun C. , Gabrielsen Christina , Nes Ingolf F. , Amdam Gro V. , Diep Dzung B.
Published: March 2015

Lactobacillus kunkeei
is a common inhabitant in honey bee gut, being present in several parts of the world. Here, we describe the draft genome of L. kunkeei AR114, an isolate from late foraging season in Norway.
Complete Genome Sequence of the Persistent Listeria monocytogenes Strain R479a
Authors: Schmitz-Esser Stephan , Gram Lone , Wagner Martin
Published: March 2015

The complete genome sequence of the persistent
Listeria monocytogenes
strain R479a isolated from smoked salmon in Denmark and belonging to lineage II, serovar 1/2a, and multilocus sequence type 8 (ST8) is presented here.
Paroxysmal non-kinesigenic dyskinesia, post-streptococcal syndromes and psychogenic movement disorders: a diagnostic challenge
Authors: Peila Elena , Mortara Paolo , Cicerale Alessandro , Pinessi Lorenzo
Published: March 2015

We report a case of a 15-year-old boy presenting with sudden attacks of hyperkinetic movements of the limbs, trunk and neck. Clinical features were suggestive of paroxysmal non-kinesigenic dyskinesia, but the elevated antistreptolysin O antibody titre and history of recurrent upper airways infection led us to consider a post-streptococcal syndrome as a possible diagnosis. The patient started therapy with benzathine penicillin, sodium valproate and clonazepam without any significant improvement. A successive psychiatric assessment revealed the presence of a psychogenic movement disorder. Psychodynamic psychotherapy and individual counselling were started with progressive improvement of psychological symptoms and gradual resolution of hyperkinetic episodes, without any recurrence recorded during the follow-up (10 months).
Testicular non-Hodgkin's lymphoma presenting in a young adult
Authors: Ratkal Vishal , Chawla Arun , Mishra Dilip Kumar , Monappa Vidya
Published: March 2015

We report a case of a 27-year-old man who presented with a slowly growing left testicular swelling associated with mild pain over a period of 3 months. He was evaluated by his family physician with scrotal ultrasound and testicular tumour markers. He was diagnosed and treated as epididymo-orchitis and managed with antibiotics. When he later presented to us, he had an enlarged left testis with normal spermatic cord. Scrotal Doppler evaluation showed a globally enlarged left testis and epididymis with increased vascularity in the left testis, with the right testis being normal. Testicular tumour markers were normal. Fine-needle aspiration cytology of the left testis was suggestive of lymphoma. Exploration through an inguinal approach was carried out and a Chevassu manoeuvre with frozen section study was performed, which was reported as non-Hodgkin's lymphoma. Left radical orchidectomy was performed. Histopathology reported diffuse large B-cell lymphoma, of a germinal centre type. Contrast CT of the abdomen, chest and brain were normal. Sperm cryopreservation was carried out. The patient was started on chemotherapy with cyclophosphamide, hydroxydaunorubicin, oncovin, prednisone (CHOP) regime.
Novel high-sensitivity troponin assay requires higher cut-off value to separate acute myocardial infarction from non-acute myocardial infarction in a high-risk population
Authors: Wassef Anthony Wafik Aziz , Hiebert Brett , Saeed Mahwash F. , Tam James W.
Published: March 2015

Purpose: The novel high-sensitivity troponin T assay (hs-cTnT) has been validated for diagnosing AMI in the emergency room. However its utility in high-risk in-patient populations is unknown. Methods: We retrospectively reviewed admissions to a general cardiology unit that had 2 hs-cTnT measurements in the first 12 h of presentation. We assessed 8 diagnostic algorithms that used hs-cTnT concentration and changes in concentration (including the 99th percentile cut-off of 14 ng/L) for their diagnostic utility in separating AMI patients from cardiac/nonACS and non-cardiac chest-pain patients. UA was excluded. Results: There were 233 patients (mean age 67 years, 153 were males (66%)) admitted over a 2 month period, with AMI diagnosed in 118 of these patients (51%). The recommended 99th percentile cut-off had modest accuracy (65%), good sensitivity (88%), and poor specificity (25%); a higher cut-off of 75 ng/L had a better diagnostic accuracy of 73%, p < 0.05. While some hs-cTnT algorithms were either highly sensitive or specific, none were both. Conclusion: In high-risk cardiology in-patients, no hs-cTnT concentration cut-off or change more accurately diagnosed and excluded AMI, although higher cut-offs had better diagnostic utility.
Is erythrocyte size a strategy to avoid hypoxia in Wiegmann’s Torquate Lizards (Sceloporus torquatus)? Field evidence
Authors: González-Morales Juan C. , Quintana Erendira , Díaz-Albiter Hector , Guevara-Fiore Palestina , Fajardo Victor
Published: March 2015

This study examined changes in certain hematological parameters in a reptilian model naturally exposed to altitude-associated hypoxia. Four populations of the Mexican lizard Sceloporus torquatus Wiegmann, 1828 (Wiegmann’s Torquate Lizard) from different altitudes were sampled to evaluate erythrocyte count (Erc), hematocrit (Hct), mean corpuscular hemoglobin concentration (MCHC), and erythrocyte size (Ers). Blood was also assayed to determine hemoglobin ([Hb]), glucose, lactate, and electrolyte concentrations. Erc was performed using a Neubauer hemocytometer. Hct was calculated as percentage of packed cell volume by centrifuging blood samples. [Hb] was determined using a Bausch and Lomb Spectronic colorimeter. MCHC was calculated with the formula 100 × [Hb]/Hct. Ers was calculated from blood smear microphotographs analyzed with the Sigma Scan Pro software. Values of serum electrolytes (sodium (Na+), potassium (K+), and calcium (Ca2+)), pH, glucose, and lactate from blood samples were obtained through a blood electrolyte analyzer. Highland populations of S. torquatus exhibited a significant increase in Erc, Hct, Ers, and [Hb]. In contrast, MCHC showed no correlation with altitude. Additionally, significant differences in lactate, Na+, K+, and Ca2+were observed in highland populations. In general, we found that most hematological parameters were significantly different among lizard populations from different altitudes. This is the first study to report changes in Ers in relation to altitude, which could be a physiological response to hypoxia.
Carbon budgets of boreal lakes: state of knowledge, challenges, and implications
Authors: Anas M.U. Mohamed , Scott Kenneth A. , Wissel Björn
Published: March 2015

Converging evidence suggests that freshwater systems play an important role in the carbon cycles at both regional and global scales. In addition, there are serious concerns that ongoing and future changes to the environment could alter these dynamics. This is particularly important in the boreal forest biome, which contains a very high density of lakes. In this review, we synthesize the current state of research to provide a critical overview of (i) the role of boreal lakes as emitters versus sinks of carbon, (ii) their contribution to the regional carbon balance, (iii) knowledge gaps that may inhibit an accurate evaluation of the role of boreal lakes in a landscape context, and (iv) impacts of environmental perturbations on carbon dynamics in boreal lakes. Several recent studies indicate that boreal lakes are actively processing, emitting, and storing carbon rather than being passive transport conduits. Yet, generalizing the role of lake ecosystems for the overall carbon balance of the boreal forest biome is challenging because of the scarcity of studies on lake carbon budgets in a landscape context that can capture the potential temporal and spatial variability and uncertainties associated with the available estimates of carbon pools and fluxes. Further, environmental perturbations, such as climate change, acidic deposition, and nutrient enrichment, likely affect both carbon export to lakes and in-lake carbon processing in boreal regions. Predicting their overall impacts on lake carbon budgets is particularly difficult, not only because individual environmental stressors likely affect multiple processes involved in carbon cycling, but also because often multiple stressors act synergistically or antagonistically at the landscape level. Accordingly, long-term, system-wide approaches are required to accurately evaluate the importance of lakes for boreal carbon budgets in a changing environment.
Connecting leptonic CP violation, lightest neutrino mass and baryon asymmetry through type II seesaw
Authors: Kalita Rupam , Borah Debasish
Published: March 2015

We study the possibility of connecting leptonic Dirac CP phase δ, lightest neutrino mass and baryon asymmetry of the universe within the framework of a model where both type I and type II seesaw mechanisms contribute to neutrino mass. Type I seesaw gives rise to Tri-Bimaximal (TBM) type neutrino mixing whereas type II seesaw acts as a correction in order to generate nonzero θ13. We derive the most general form of type II seesaw mass matrix which cannot only give rise to correct neutrino mixing angles but also can generate nontrivial value of δ. Considering both the cases where type II seesaw is subleading and is equally dominant compared to type I seesaw, we correlate the type II seesaw term with δ and lightest neutrino mass. We further constrain the Dirac CP phase δ and hence the type II seesaw mass matrix from the requirement of producing the observed baryon asymmetry through the mechanism of leptogenesis.
PORTFOLIO RETURN DISTRIBUTIONS: SAMPLE STATISTICS WITH STOCHASTIC CORRELATIONS
Authors: CHETALOVA DESISLAVA , SCHMITT THILO A. , SCHÄFER RUDI , GUHR THOMAS
Published: March 2015

We consider random vectors drawn from a multivariate normal distribution and compute the sample statistics in the presence of stochastic correlations. For this purpose, we construct an ensemble of random correlation matrices and average the normal distribution over this ensemble. The resulting distribution contains a modified Bessel function of the second kind whose behavior differs significantly from the multivariate normal distribution, in the central part as well as in the tails. This result is then applied to asset returns. We compare with empirical return distributions using daily data from the NASDAQ Composite Index in the period from 1992 to 2012. The comparison reveals good agreement, the average portfolio return distribution describes the data well especially in the central part of the distribution. This in turn confirms our ansatz to model the nonstationarity by an ensemble average.
LEFT-WING ASYMPTOTICS OF THE IMPLIED VOLATILITY IN THE PRESENCE OF ATOMS
Authors: GULISASHVILI ARCHIL
Published: March 2015

The paper considers the asymptotic behavior of the implied volatility in stochastic asset price models with atoms. In such models, the asset price distribution has a singular component at zero. Examples of models with atoms include the constant elasticity of variance (CEV) model, jump-to-default models, and stochastic models described by processes stopped at the first hitting time of zero. For models with atoms, the behavior of the implied volatility at large strikes is similar to that in models without atoms. On the other hand, the behavior of the implied volatility at small strikes is influenced significantly by the atom at zero. De Marco, Hillairet, and Jacquier found an asymptotic formula for the implied volatility at small strikes with two terms and also provided an incomplete description of the third term. In the present paper, we obtain a new asymptotic formula for the left wing of the implied volatility, which is qualitatively different from the De Marco–Hillairet–Jacquier formula. The new formula contains three explicit terms and an error estimate. In the paper, we show how to derive the De Marco–Hillairet–Jacquier formula from the new formula, and compare the performance of the two formulas in the case of the CEV model. The graphs included in the paper show that the new asymptotic formula provides a notably better approximation to the implied volatility at small strikes in the CEV model than the De Marco–Hillairet–Jacquier formula.
LIQUIDITY RISK, INSTEAD OF FUNDING COSTS, LEADS TO A VALUATION ADJUSTMENT FOR DERIVATIVES AND OTHER ASSETS
Authors: NAUTA BERT-JAN
Published: March 2015

Traditionally derivatives have been valued in isolation. The balance sheet of which a derivative position is part, was not included in the valuation. Recently however, aspects of the valuation have been revised to incorporate certain elements of the balance sheet. Examples are the debt valuation adjustment which incorporates default risk of the bank holding the derivative, and the funding valuation adjustment that some authors have proposed to include the cost of funding into the valuation. This paper investigates the valuation of derivatives as part of a balance sheet. In particular, the paper considers funding costs, default risk and liquidity risk. A valuation framework is developed under the elastic funding assumption. This assumption states that funding costs reflect the quality of the assets, and any change in asset composition is immediately reflected in the funding costs. The result is that funding costs should not affect the value of derivatives. Furthermore, a new model for pricing liquidity risk is described. The paper highlights that the liquidity spread, used for discounting cashflows of illiquid assets, should be expressed in terms of the liquidation value (LV) of the asset, and the probability that the institution holding the asset needs to liquidate its assets.
DETERMINANTS OF PHYSICIANS' PURCHASE INTENTION FOR INNOVATIVE SERVICES: INTEGRATING PROFESSIONAL CHARACTERISTICS WITH TECHNOLOGY ACCEPTANCE MODEL AND THEORY OF PLANNED BEHAVIOUR
Authors: KOSTOPOULOS GIANNIS , RIZOMYLIOTIS IOANNIS , KONSTANTOULAKI KLEOPATRA
Published: March 2015

This paper seeks to explore the factors that influence physicians' purchase intention for supplementary professional services that have been recently introduced to the market. For that reason, a model has been developed and empirically tested using data collected from 100 physicians regarding an innovative e-detailing service. Results show that physicians' purchase intention is significantly influenced by five factors. Three of them derive from the integration of Technology Acceptance Model (TAM) with the Theory of Planned Behaviour (TPB), i.e., perceived usefulness, perceived ease of use and professional image. The rest, namely work experience, working status and innovativeness, refer to physicians' professional characteristics. Work experience and innovativeness were found to have a significant effect on physicians' perceptions of the innovative service, whereas, physicians' current working status was not found to have significant influence on either their perceptions of the innovative service or their purchase intention.
Water Demand by Unconnected Urban Households in Rwanda
Authors: Uwera Claudine , Stage Jesper
Published: March 2015

In this paper, we analyze water demand by urban households in Rwanda who currently lack a piped connection into their home. The analysis uses data from a cross-sectional survey. The results show that public taps are the most widely used water source and that the demand for water from this source is more inelastic than that for water from other water sources. Although some households combine different sources of water, the majority in the sample uses only one source. We use the full household income, including the value of the household's time, and obtain results which indicate income elasticities higher than those obtained using monetary income only. The full cost associated with alternative water sources (including the opportunity cost of the time used) is shown to be important for determining the choice of source — something which has been overlooked in most previous studies.
Sedimentation in remnant ocean basin off SW Taiwan with implication for closing northeastern South China Sea
Authors: Hsiung K.-H. , Yu H.-S. , Su M.
Published: March 2015

Taiwan is one of the most cited examples of modern mountain building in an oblique arc–continent collision. However, the recognition and significance of the Taiwan remnant ocean basin in the final stages of the collision of Luzon with the Chinese margin have long been ignored. This paper emphasizes the Taiwan remnant ocean basin as the main sink for sediments from the uplifted Taiwan suture zone and as a record of clues to the suturing history of the Taiwan collision zone. A part of the palaeo South China Sea has been closed by oblique collision of the Luzon Arc with the Chinese margin in the Taiwan region since about 4 Ma. As collision continued southward along the Taiwan–Luzon convergent zone the remaining South China Sea off SW Taiwan became the Taiwan remnant ocean basin. Beginning about 1.6 Ma much sediment from the longitudinal drainage of the Taiwan orogen was fed into this remaining basin and trapped in the intra-slope basins of the Kaoping slope, with some sediment bypassing via the Kaoping Canyon to the lower reach of the Penghu Canyon. This basin is characteristic of an axial canyon–deep-sea channel–oceanic trench system without significant sediment accumulation in submarine fans. Excess sediments from the Penghu Canyon mainly spill over out of the closing basin to the South China Sea and Manila Trench via the deep-sea Penghu Channel. The Taiwan–Luzon convergent zone continues along the NE South China Sea where the Taiwan remnant ocean basin exists. The implication of the convergence is that the Taiwan remnant ocean basin will keep shrinking in the next few million years southward to the northern end of the Manila Trench at around 20°N, where collision is replaced by subduction. The remnant ocean basin would be closed and deformed, and sediments would be accreted to uplifted collisional terranes north of the Manila Trench.
U–Pb zircon constraints on obduction initiation of the Unst Ophiolite: an oceanic core complex in the Scottish Caledonides?
Authors: Crowley Q. G. , Strachan R. A.
Published: March 2015

The Unst Ophiolite is the best exposed of a chain of early Ordovician ophiolites in the Scottish Caledonides and is widely regarded as having formed in a supra-subduction zone setting within the Iapetus Ocean. Reinterpretation of sheeted dykes suggests that it formed as an oceanic core complex, presumably during subduction roll-back immediately prior to obduction onto the Laurentian margin. A new U–Pb zircon age of 484 ± 4 Ma for development of the metamorphic sole places a lower limit on the timing of obduction, which was subsequently followed by regional-scale crustal thickening and Barrovian metamorphism during the Grampian orogenic event.

Supplementary material:

Analytical methods, CL images of representative zircon grains and an LA-ICP-MS U–Th–Pb zircon data table are available at
www.geolsoc.org.uk/SUP18814
.
Resource management and a Best Available Concept for aggregate sustainability
Authors: Danielsen S. W. , Kuznetsova E.
Published: March 2015

Aggregates are major constituents in construction, the global demand for which approaches some 22 billion tonnes per year. Some major challenges follow: firstly, the dependency on geological conditions and the availability of resources; secondly, the traffic, emissions and energy use connected with transportation; thirdly, the technology of utilizing resources with a variety of properties to meet user requirements; and finally, the need for increased awareness, particularly over issues like land-use conflicts, environmental impact of the aggregate and quarrying industry, and the need to make these activities sustainable.

Aggregate standards have primarily been written by engineers, and engineers are first of all concerned with technical requirements. However, in the future, there will be a greater focus on environmental impact and sustainability.

Geological resources are non-renewable, which, for example, can be seen in the rapid depletion of natural sand/gravel deposits. This causes increasing awareness along with environmental impact, conflicts of interest concerning land use, sustainability in mass balance and – not least – increasing transport distances required to get the materials to the places of use.

The principle of a Best Available Concept (BAC) for aggregate production and use is introduced, working with four essential phases: inventory and planning; quarrying and production; use of aggregates; and reclamation of mined-out areas. In order to compare alternatives and calculate environmental and economic consequences of decisions, it is recommended that new LCC (Life Cycle Cost) and LCA (Life Cycle Assessment) tools are worked with, which have been recently developed in two EU (European Union) funded research projects.
Calcium-sensing receptor stimulates Cl−- and SCFA-dependent but inhibits cAMP-dependent HCO3− secretion in colon
Authors: Tang Lieqi , Peng Minzhi , Liu Li , Chang Wenhan , Binder Henry J. , Cheng Sam X.
Published: March 2015

Colonic bicarbonate (HCO3−) secretion is a well-established physiological process that is closely linked to overall fluid and electrolyte movement in the mammalian colon. These present studies show that extracellular calcium-sensing receptor (CaSR), a fundamental mechanism for sensing and regulating ionic and nutrient compositions of extracellular milieu in the small and large intestine, regulates HCO3− secretion. Basal and induced HCO3− secretory responses to CaSR agonists were determined by pH stat techniques used in conjunction with short-circuit current measurements in mucosa from rat distal colon mounted in Ussing chambers. R568, a specific CaSR activator, stimulated lumen Cl−- and short-chain fatty acid (SCFA)-dependent HCO3− secretion but inhibited cyclic nucleotide-activated HCO3− secretion. Consequently, at physiological conditions (either at basal or during lumen acid challenge) when electroneutral Cl−/HCO3− and SCFA/HCO3− exchangers dominate, CaSR stimulates HCO3− secretion; in contrast, in experimental conditions that stimulate fluid and HCO3− secretion, e.g., when forskolin activates electrogenic cystic fibrosis transmembrane conductance regulator-mediated HCO3− conductance, CaSR activation inhibits HCO3− secretion. Corresponding changes in JHCO3 (μeq·h−1·cm−2, absence vs. presence of R568) were 0.18 ± 0.03 vs. 0.31 ± 0.08 under basal nonstimulated conditions and 1.85 ± 0.23 vs. 0.45 ± 0.06 under forskolin-stimulated conditions. Similarly, activation of CaSR by R568 stimulated Cl−- and SCFA-dependent HCO3− secretion and inhibited cAMP-dependent HCO3− secretion in colon mucosa of wild-type mice; such effects were abolished in CaSR-null mice. These results suggest a new paradigm for regulation of intestinal ion transport in which HCO3− secretion may be fine-tuned by CaSR in accordance with nutrient availability and state of digestion and absorption. The ability of CaSR agonists to inhibit secretagogue-induced intestinal HCO3− secretion suggests that modulation of CaSR activity may provide a new therapeutic approach to correct HCO3− deficit and metabolic acidosis, a primary cause of morbidity and mortality in acute infectious diarrheal illnesses.
Mitochondrial DNA damage-associated molecular patterns mediate a feed-forward cycle of bacteria-induced vascular injury in perfused rat lungs
Authors: Kuck Jamie L. , Obiako Boniface O. , Gorodnya Olena M. , Pastukh Viktor M. , Kua Justin , Simmons Jon D. , Gillespie Mark N.
Published: March 2015

Fragments of the mitochondrial genome released into the systemic circulation after mechanical trauma, termed mitochondrial DNA damage-associated molecular patterns (mtDNA DAMPs), are thought to mediate the systemic inflammatory response syndrome. The close association between circulating mtDNA DAMP levels and outcome in sepsis suggests that bacteria also might be a stimulus for mtDNA DAMP release. To test this hypothesis, we measured mtDNA DAMP abundance in medium perfusing isolated rat lungs challenged with an intratracheal instillation of 5 × 107 colony-forming units of Pseudomonas aeruginosa (strain 103; PA103). Intratracheal PA103 caused rapid accumulation of selected 200-bp sequences of the mitochondrial genome in rat lung perfusate accompanied by marked increases in both lung tissue oxidative mtDNA damage and in the vascular filtration coefficient ( Kf). Increases in lung tissue mtDNA damage, perfusate mtDNA DAMP abundance, and Kf were blocked by addition to the perfusion medium of a fusion protein targeting the DNA repair enzyme Ogg1 to mitochondria. Intra-arterial injection of mtDNA DAMPs prepared from rat liver mimicked the effect of PA103 on both Kf and lung mtDNA integrity. Effects of mtDNA and PA103 on Kf were also attenuated by an oligodeoxynucleotide inhibitor of Toll-like receptor 9 (TLR-9) by mitochondria-targeted Ogg1 and by addition of DNase1 to the perfusion medium. Collectively, these findings are consistent with a model wherein PA103 causes oxidative mtDNA damage leading to a feed-forward cycle of mtDNA DAMP formation and TLR-9-dependent mtDNA damage that culminates in acute lung injury.
Advances in Multiferroic Nanomaterials Assembled with Clusters
Authors: Zhao Shifeng
Published: March 2015

As an entirely new perspective of multifunctional materials, multiferroics have attracted a great deal of attention. With the rapidly developing micro‐ and nano‐electro‐mechanical system (MEMS&NEMS), the new kinds of micro‐ and nanodevices and functionalities aroused extensive research activity in the area of multiferroics. As an ideal building block to assemble the nanostructure, cluster exhibits particular physical properties related to the cluster size at nanoscale, which is efficient in controlling the multiferroic properties for nanomaterials. This review focuses on our recent advances in multiferroic nanomaterials assembled with clusters. In particular, the single phase multiferroic films and compound heterostructured multiferroic films assembled with clusters were introduced detailedly. This technique presents a new and efficient method to produce the nanostructured multiferroic materials for their potential application in NEMS devices.
The Role of Ovarian Sex Steroids in Metabolic Homeostasis, Obesity, and Postmenopausal Breast Cancer: Molecular Mechanisms and Therapeutic Implications
Authors: Boonyaratanakornkit Viroj , Pateetin Prangwan
Published: March 2015

Obese postmenopausal women have an increased risk of breast cancer and are likely to have a worse prognosis than nonobese postmenopausal women. The cessation of ovarian function after menopause results in withdrawal of ovarian sex steroid hormones, estrogen, and progesterone. Accumulating evidence suggests that the withdrawal of estrogen and progesterone causes homeostasis imbalances, including decreases in insulin sensitivity and leptin secretion and changes in glucose and lipid metabolism, resulting in a total reduction in energy expenditure. Together with a decrease in physical activity and consumption of a high fat diet, these factors significantly contribute to obesity in postmenopausal women. Obesity may contribute to breast cancer development through several mechanisms. Obesity causes localized inflammation, an increase in local estrogen production, and changes in cellular metabolism. In addition, obese women have a higher risk of insulin insensitivity, and an increase in insulin and other growth factor secretion. In this review, we describe our current understanding of the molecular actions of estrogen and progesterone and their contributions to cellular metabolism, obesity, inflammation, and postmenopausal breast cancer. We also discuss how modifications of estrogen and progesterone actions might be used as a therapeutic approach for obesity and postmenopausal breast cancer.
Synthesis and Characterization of Hierarchical Structured TiO2 Nanotubes and Their Photocatalytic Performance on Methyl Orange
Authors: Liu Kai , Lin Shiwei , Liao Jianjun , Pan Nengqian , Zeng Min
Published: March 2015

Hierarchical structured TiO2 nanotubes were prepared by mechanical ball milling of highly ordered TiO2 nanotube arrays grown by electrochemical anodization of titanium foil. Scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, specific surface area analysis, UV‐visible absorption spectroscopy, photocurrent measurement, photoluminescence spectra, electrochemical impedance spectra, and photocatalytic degradation test were applied to characterize the nanocomposites. Surface area increased as the milling time extended. After 5 h ball milling, TiO2 hierarchical nanotubes exhibited a corn‐like shape and exhibited enhanced photoelectrochemical activity in comparison to commercial P25. The superior photocatalytic activity is suggested to be due to the combined advantages of high surface area of nanoparticles and rapid electron transfer as well as collection of the nanotubes in the hierarchical structure. The hierarchical structured TiO2 nanotubes could be applied into flexible applications on solar cells, sensors, and other photoelectrochemical devices.
Pregabalin and Tranexamic Acid Evaluation by Two Simple and Sensitive Spectrophotometric Methods
Authors: Sher Nawab , Fatima Nasreen , Perveen Shahnaz , Siddiqui Farhan Ahmed , Wafa Sial Alisha
Published: March 2015

This paper demonstrates colorimetric visible spectrophotometric quantification methods for amino acid, namely, tranexamic acid and pregabalin. Both drugs contain the amino group, and when they are reacted with 2,4-dinitrophenol and 2,4,6-trinitrophenol, they give rise to yellow colored complexes showing absorption maximum at 418 nm and 425 nm, respectively, based on the Lewis acid base reaction. Detailed optimization process and stoichiometric studies were conducted along with investigation of thermodynamic features, that is, association constant and standard free energy changes. The method was linear over the concentration range of 0.02–200 µgmL−1with correlation coefficient of more than 0.9990 in all of the cases. Limit of detection was in range from 0.0041 to 0.0094 µgmL−1and limit of quantification was in the range from 0.0137 to 0.0302 µgmL−1. Excellent recovery in Placebo spiked samples indicated that there is no interference from common excipients. The analytical methods under proposal were successfully applied to determine tranexamic acid and pregabalin in commercial products.t-testandFratio were evaluated without noticeable difference between the proposed and reference methods.
Enhancing Both Efficiency and Representational Capability of Isomap by Extensive Landmark Selection
Authors: Liang Dong , Qiao Chen , Xu Zongben
Published: March 2015

The problems of improving computational efficiency and extending representational capability are the two hottest topics in approaches of global manifold learning. In this paper, a new method called extensive landmark Isomap (EL-Isomap) is presented, addressing both topics simultaneously. On one hand, originated from landmark Isomap (L-Isomap), which is known for its high computational efficiency property, EL-Isomap also possesses high computational efficiency through utilizing a small set of landmarks to embed all data points. On the other hand, EL-Isomap significantly extends the representational capability of L-Isomap and other global manifold learning approaches by utilizing only an available subset from the whole landmark set instead of all to embed each point. Particularly, compared with other manifold learning approaches, the data manifolds with intrinsic low-dimensional concave topologies and essential loops can be unwrapped by the new method more successfully, which are shown by simulation results on a series of synthetic and real-world data sets. Moreover, the accuracy, robustness, and computational complexity of EL-Isomap are analyzed in this paper, and the relation between EL-Isomap and L-Isomap is also discussed theoretically.
Determination of Polar Compounds in Guava Leaves Infusions and Ultrasound Aqueous Extract by HPLC-ESI-MS
Authors: Díaz-de-Cerio Elixabet , Verardo Vito , Gómez-Caravaca Ana María , Fernández-Gutiérrez Alberto , Segura-Carretero Antonio
Published: March 2015

Literature lacks publications about polar compounds content in infusion or guava leaves tea. Because of that, a comparison between different times of infusion and a conventional ultrasound aqueous extract was carried out. Several polar compounds have been identified by HPLC-ESI-MS and their antioxidant activity was evaluated by FRAP and ABTS assays. Four different classes of phenolic compounds (gallic and ellagic acid derivatives, flavonols, flavanones, and flavan-3-ols) and some benzophenones were determined. The quantification results reported that the order, in terms of concentration of the classes of polar compounds in all samples, was flavonols > flavan-3-ols > gallic and ellagic acid derivatives > benzophenones > flavanones. As expected, the aqueous extract obtained by sonication showed the highest content in the compounds studied. Significative differences were noticed about the different times of infusion and five minutes was the optimal time to obtain the highest content in polar compounds using this culinary method. All the identified compounds, except HHDP isomers and naringenin, were positively correlated with antioxidant activity.
Application of an Activated Carbon-Based Support for Magnetic Solid Phase Extraction Followed by Spectrophotometric Determination of Tartrazine in Commercial Beverages
Authors: Rodríguez José A. , Escamilla-Lara Karen A. , Guevara-Lara Alfredo , Miranda Jose M. , Páez-Hernández Ma. Elena
Published: March 2015

A method is presented for magnetic solid phase extraction of tartrazine from nonalcoholic beverages. The method involves the extraction and clean-up by activated carbon covered with magnetite dispersed in the sample, followed by the magnetic isolation and desorption of the analyte by basified methanol. The tartrazine eluted from the magnetic support was determined by spectrophotometry. Under optimal conditions, the linear range of the calibration curve ranges from 3 to 30 mg L−1, with a limit of detection of 1 mg L−1. The method was validated by comparing the results with those obtained by HPLC. A precision of<5.0% was obtained in all cases and no significant differences were observed(P<0.05).
Photoresponse of Long-Wavelength AlGaAs/GaAs Quantum Cascade Detectors
Authors: Li Liang , Xiong Dayuan
Published: March 2015

We study the photoresponse and photocurrents of long-wavelength infrared quantum cascade detectors (QCDs) based on AlGaAs/GaAs material system. The photocurrent spectra were measured at different temperatures from 20 K to 100 K with a low noise Fourier transforming infrared spectrometer. The main response peak appeared at 8.9 μm while four additional response peaks from 4.5 μm to 10.1 μm were observed as well. We confirmed that the photocurrent comes from phonon assisted tunneling and the multipeak behavior comes from the complicated optical transition in the quantum cascade structure. This work is valuable for the future design and optimization of QCD devices.
New Insights into Glomerular Parietal Epithelial Cell Activation and Its Signaling Pathways in Glomerular Diseases
Authors: Su Hua , Chen Shan , He Fang-Fang , Wang Yu-Mei , Bondzie Philip , Zhang Chun
Published: March 2015

The glomerular parietal epithelial cells (PECs) have aroused an increasing attention recently. The proliferation of PECs is the main feature of crescentic glomerulonephritis; besides that, in the past decade, PEC activation has been identified in several types of noninflammatory glomerulonephropathies, such as focal segmental glomerulosclerosis, diabetic glomerulopathy, and membranous nephropathy. The pathogenesis of PEC activation is poorly understood; however, a few studies delicately elucidate the potential mechanisms and signaling pathways implicated in these processes. In this review we will focus on the latest observations and concepts about PEC activation in glomerular diseases and the newest identified signaling pathways in PEC activation.