bluuebunny/crossref_metadata_2025_split huggingface dataset:
MAPK Phosphatase-2 (MKP-2) Is Induced by hCG and Plays a Role in the Regulation of CYP11A1 Expression in MA-10 Leydig Cells
Authors: Gómez Natalia V. , Gorostizaga Alejandra B. , Mori Sequeiros García María M. , Brion Laura , Acquier Andrea , González-Calvar Silvia I. , Méndez Carlos F. , Podestá Ernesto J. , Paz Cristina 
Published: March 2013

AbstractMAPKs such as ERK1/2 are dephosphorylated, and consequently inactivated, by dual specificity phosphatases (MKPs). In Leydig cells, LH triggers ERK1/2 phosphorylation through the action of protein kinase A. We demonstrate that, in MA-10 Leydig cells, LH receptor activation by human chorionic gonadotropin (hCG) up-regulates MKP-2, a phosphatase that dephosphorylates ERK1/2, among other MAPKs. After 2 hours, hCG and 8-bromo-cAMP (8Br-cAMP) significantly increased MKP-2 mRNA levels (3-fold), which declined to basal levels after 6 hours. MKP-2 protein accumulation exhibited a similar kinetic profile. In cells transiently expressing flag-MKP-2 protein, hCG/8Br-cAMP stimulation promoted the accumulation of the chimera (2.5-fold after 3 h of stimulation). Pharmacologic and biochemical approaches showed that the accumulation of flag-MKP-2 involves a posttranslational modification that increases MKP-2 half-life. MKP-2 down-regulation by a short hairpin RNA (MKP-2 shRNA) raised the levels of phosphorylated ERK1/2 reached by 8Br-cAMP stimulation. This effect was evident after 180 min of stimulation, which suggests that MKP-2 down-regulates the late phase of cAMP-induced ERK1/2 activity. Also, MKP-2 down-regulation by MKP-2 shRNA increased the stimulatory effect of 8Br-cAMP on both promoter activity and messenger levels of CYP11A1, which encodes for the steroidogenic enzyme P450scc and is induced by LH/hCG through protein kinase A and ERK1/2 activities. Our findings demonstrate, for the first time, that LH/hCG tightly regulates MKP-2 expression, which modulates the induction of CYP11A1 by 8Br-cAMP. MKP-2 up-regulation might control ERK1/2 activity in a specific temporal frame to modulate the expression of a finite repertory of ERK-dependent genes.
The permeability of red blood cells to chloride, urea, and water
Authors: Brahm Jesper 
Published: March 2013

Summary
Red blood cell (RBC) permeability (P, cm s-1) of human, dog, chick, duck, and Amphiuma means to 36Cl-, 14C-urea, and 3H2O was determined under self-exchange conditions (25°C, pH 7.2-7.5). PCl of all RBC species is 0.9-2.7 × 10-4 at CCl 127-150 mM. Purea is 0.83 × 10-6 in chick and 1.65 × 10-6 in duck RBC at Curea 1-500 mM. In human, dog, and Amphiuma RBC Purea is concentration-dependent at 1-1000 mM (Michaelis-Menten-like kinetics; K½ respectively 345, 173, 107 mM). At 1 mM urea Purea is 2.60 × 10-4 (human), 4.67 × 10-4 (dog), and 0.30 × 10-4 (Amphiuma). Diffusional water permeability Pd is 0.39 × 10-3 (Amphiuma), 0.84 × 10-3 (chick), 2.35 × 10-3 (human), 3.13 × 10-3 (dog), and 5.95 × 10-3 (duck). DIDS, DNDS, and phloretin inhibited PCl &gt;99%. PCMBS, PCMB, and phloretin inhibited Purea &gt;99% in human, dog, and Amphiuma RBC. Inhibition was absent in chick and duck RBC. PCMB and PCMBS inhibited Pd in human, dog, and duck, but not chick and Amphiuma RBC. Temperature dependence, EA, kJ mol-1, of PCl is 75 (Amphiuma), 100 (dog), and 118 (duck). EA of Purea is 70 (duck), and 53 (Amphiuma). EA of Pd is 35 (duck), and 32 (Amphiuma). Combining this study of PCl, Pd, Purea, and inhibition of Psolute with our previous RBC studies indicates that anion, urea, and water transporters respectively transport only chloride (all species), only urea (human, dog, Amphiuma), and only water (human, dog, duck). Water do not share the urea transporter with urea, and the solute transport is not coupled under normal physiological conditions.
Finding the best estimates of metabolic rates in a coral reef fish
Authors: Roche Dominique G. , Binning Sandra A. , Bosiger Yoland , Johansen Jacob L. , Rummer Jodie L. 
Published: March 2013

Summary
Metabolic rates of aquatic organisms are estimated from measurements of oxygen consumption rates (ṀO2) through swimming and resting respirometry. These distinct approaches are increasingly used in eco- and conservation physiology studies; however, few studies have tested whether they yield comparable results. We examined whether two fundamental ṀO2 measures, standard metabolic rate (SMR) and maximum metabolic rate (MMR), vary based on the method employed. Ten bridled monocle bream (Scolopsis bilineatus) were exercised using (1) a critical swimming speed (Ucrit) protocol, (2) a 15 min exhaustive chase protocol and (3) a 3 min exhaustive chase protocol followed by brief air exposure. Protocol (1) was performed in a swimming respirometer whereas protocols (2) and (3) were followed by resting respirometry. SMR estimates in swimming respirometry were similar to those in resting respirometry when a three-parameter exponential or power function was used to extrapolate the swimming speed-ṀO2 relationship to zero swimming speed. In contrast, MMR using the Ucrit protocol was 36% higher than MMR derived from the 15 min chase protocol and 23% higher than MMR using the 3 min chase 1 min air exposure protocol. For strong steady (endurance) swimmers, such as S. bilineatus, swimming respirometry can produce more accurate MMR estimates than exhaustive chase protocols because oxygen consumption is measured during exertion. However, when swimming respirometry is impractical, exhaustive chase protocols should be supplemented with brief air exposure to improve measurement accuracy. Caution is warranted when comparing MMR estimates obtained with different respirometry methods unless they are cross-validated on a species-specific basis.
Sodalite Layer as a Protective Barrier for Diesel Particulate Filters
Authors: Dinh Thanh-Nghia , Kimura Riichiro , Kamimura Yoshihiro , Ogura Masaru , Okubo Tatsuya 
Published: March 2013

Abstract
We report the preparation of a sodalite (SOD) layer on a cordierite substrate as a protective barrier against the potassium species using an in situ hydrothermal method. The performance of the potassium carbonate-loaded layer was characterized by scanning electron microscopy–energy-dispersive X-ray (SEM-EDX) measurements before and after thermal treatment at 1073 K for 5 and 50 h. A low potassium content detected at the layer–substrate interface of the samples before and after heating for 5 h indicates that the cordierite substrate was protected against potassium species by the generated SOD layer, whereas heating for the longer period of 50 h resulted in further migration of potassium species. The mobility of the potassium species is likely to be principally governed by diffusion along the defects of the material that appear during thermal treatment. It is suggested that migration of the potassium species might be prevented by the formation of a defect-free layer.
Anacardic acid, a histone acetyltransferase inhibitor, modulates LPS-induced IL-8 expression in a human alveolar epithelial cell line A549
Authors: Yasutake Tetsuo , Wada Hiroo , Higaki Manabu , Nakamura Masuo , Honda Kojiro , Watanabe Masato , Ishii Haruyuki , Kamiya Shigeru , Takizawa Hajime , Goto Hajime 
Published: March 2013

Objective and design:The histone acetylation processes, which are believed to play a critical role in the regulation of many inflammatory genes, are reversible and regulated by histone acetyltransferases (HATs), which promote acetylation, and histone deacetylases (HDACs), which promote deacetylation. We studied the effects of lipopolysaccharide (LPS) on histone acetylation and its role in the regulation of interleukin (IL)-8 expression. Material:A human alveolar epithelial cell line A549 was usedinvitro.Methods:Histone H4 acetylation at the IL-8 promoter region was assessed by a chromatin immunoprecipitation (ChIP) assay. The expression and production of IL-8 were evaluated by quantitative polymerase chain reaction and specific immunoassay. Effects of a HDAC inhibitor, trichostatin A (TSA), and a HAT inhibitor, anacardic acid, were assessed. Results:Escherichia coli-derived LPS showed a dose- and time-dependent stimulatory effect on IL-8 protein production and mRNA expression in A549 cellsin vitro. LPS showed a significant stimulatory effect on histone H4 acetylation at the IL-8 promoter region by ChIP assay. Pretreatment with TSA showed a dose-dependent stimulatory effect on IL-8 release from A549 cells as compared to LPS alone. Conversely, pretreatment with anacardic acid inhibited IL-8 production and expression in A549 cells. Conclusion:These data suggest that LPS-mediated proinflammatory responses in the lungs might be modulated via changing chromatin remodeling by HAT inhibition.
Optimal isoperimetric inequalities for complete proper minimal submanifolds in hyperbolic space
Authors: Min Sung-Hong , Seo Keomkyo 
Published: March 2013

Abstract

Let Σ be a k-dimensional complete proper minimal submanifold in the Poincaré ball model Bn
of hyperbolic geometry. If we consider Σ as a subset of the unit ball Bn
in Euclidean space, we can measure the Euclidean volumes of the given minimal submanifold Σ and the ideal boundary

∂
∞

Σ

$\partial _\infty \Sigma $

, say

Vol
ℝ

(
Σ
)

$\operatorname{Vol}_{\mathbb {R}}(\Sigma )$

and

Vol
ℝ

(

∂
∞

Σ
)

$\operatorname{Vol}_{\mathbb {R}}(\partial _\infty \Sigma )$

, respectively. Using this concept, we prove an optimal linear isoperimetric inequality. We also prove that if

Vol
ℝ

(

∂
∞

Σ
)

≥

Vol
ℝ

(

𝕊

k
-
1

)

$\operatorname{Vol}_{\mathbb {R}}(\partial _\infty \Sigma ) \ge \operatorname{Vol}_{\mathbb {R}}(\mathbb {S}^{k-1})$

, then Σ satisfies the classical isoperimetric inequality. By proving the monotonicity theorem for such Σ, we further obtain a sharp lower bound for the Euclidean volume

Vol
ℝ

(
Σ
)

$\operatorname{Vol}_{\mathbb {R}}(\Sigma )$

, which is an extension of Fraser–Schoen and Brendle's recent results to hyperbolic space.
Moreover we introduce the Möbius volume of Σ in Bn
to prove an isoperimetric inequality via the Möbius volume for Σ.
Simplicial geometry of unital lattice-ordered abelian groups
Authors: Cabrer Leonardo Manuel 
Published: March 2013

Abstract
By a unital
ℓ-group we mean a lattice-ordered abelian group with a distinguished order unit. This paper is concerned with the category

𝖴

f
p

$\mathsf {U}_{\textup {fp}}$

of finitely presented unital ℓ-groups. Using the duality between

𝖴

f
p

$\mathsf {U}_{\textup {fp}}$

and a category of rational polyhedra, we will provide (i) a construction of finite limits and co-limits in

𝖴

f
p

$\mathsf {U}_{\textup {fp}}$

; (ii) a Cantor–Bernstein–Schröder theorem for finitely presented unital ℓ-groups;
(iii) a proof that the fibered product of finitely generated projective unital ℓ-groups is projective;
(iv) a geometrical characterization of exact unital ℓ-groups.
Identification of Acoustic Emissions From Porosity and Waviness Defects in Continuous Fiber Reinforced Composites
Authors: Qamhia Issam I. , Lauer-Hunt Eric M. , El-Hajjar Rani F. 
Published: March 2013

Abstract
The manufacturing of composite structures can result in manufacturing defects such as fiber waviness and porosity. These can have a significant and usually adverse impact on the mechanical and non-mechanical properties. In this study, we propose the use of an acoustic emission methodology to study the acoustic signature when porosity and fiber waviness are present in a composite structure. The methodology shows the possibility of identifying the signals near regions of high stress concentration in specimens subject to quasi-static loading. The analysis of the acoustic waveforms is performed through temporal characterization of the acoustic emissions and individual waveform analysis. The study reveals that the presence of fiber waviness and local porosity can be detected by the time at which major events start to occur and from the recorded magnitudes of cumulative energy and counts against time. However, the combined presence of porosity and waviness results in increased difficulties in the interpretation of the acoustic emission signals. A fast Fourier transform analysis of the captured waveform is examined in order to decouple the acoustic emissions and understand the defect modes present.
Catastrophic Failure in Cavitation Erosion Testing
Authors: Meged Y. 
Published: March 2013

AbstractCatastrophic failure of metallic test specimens under cavitation erosion conditions is evidenced by an increasing rate of material loss. The typical cumulative erosion–time curve for this type of failure is denoted as type C. This type of failure depends on the characteristics of the test material, the test method, and the severity of the test conditions. A review of 264 cavitation erosion–time curves, produced via seven test methods, reveals that type C curves are found with 18 % of the specimens and 58 % of the tests performed via the rotating disc test method. This study shows that type C erosion–time curves can be modeled, analyzed, and extrapolated by means of the transient response erosion model. The two main conclusions from this study are that (i) ductile metallic materials are vulnerable to catastrophic erosion failure under severe cavitation erosion conditions, and (ii) the most effective erosion test method for the detection and classification of these materials and conditions is the rotating disc method.
Phenotypic Diversity of Root Anatomical and Architectural Traits in Zea Species
Authors: Burton Amy L. , Brown Kathleen M. , Lynch Jonathan P. 
Published: March 2013

ABSTRACTWe characterized phenotypic variation for root traits in 256 Zea spp. accessions, including maize landraces and Z. mays L. subsp. huehuetenangensis (H. H. Iltis & Doebley) Doebley, subsp. mexicana (Schrad.) H. H. Iltis, and subsp. parviglumis H. H. Iltis & Doebley, Z. nicaraguensis H. H. Iltis & B. F. Benz, Z. perennis (Hitchc.) Reeves & Mangelsd., and Z. luxurians (Durieu & Asch.) R. M. Bird. Anatomical traits included areas of the cross‐section, stele, cortex, aerenchyma, and xylem and number of cortical cells and cell files. Architectural traits included diameters of the nodal root system, individual crown roots, and the stem; numbers of seminal and nodal roots; biomass; and nodal root length and branching. Ranges for anatomical traits were similar for teosintes and landraces, except for aerenchyma and xylem areas, and number of cortical cells. Landraces had greater variation for architectural traits except for nodal root number and branching, and had larger mean stele and xylem areas, longer nodal roots, wider nodal systems, and more seminal roots than teosintes. In contrast, teosintes were smaller but had more nodal roots with greater branching. At a common plant size, teosintes would have lower mean values for all anatomical traits, except for number of cortical cells and cell files. Teosintes had greater scaled values for all architectural traits except average root diameter. Cluster analysis divided accessions into eight root phenotypes. Phenotypic diversity for root traits in the genus Zea could be a valuable resource for improving stress tolerance in maize.
Leaf Dhurrin Content is a Quantitative Measure of the Level of Pre‐ and Postflowering Drought Tolerance in Sorghum
Authors: Burke John J. , Chen Junping , Burow Gloria , Mechref Yehia , Rosenow Darrell , Payton Paxton , Xin Zhanguo , Hayes Chad M. 
Published: March 2013

ABSTRACTThe presence of preflowering or postflowering drought tolerance has been described in sorghum [Sorghum bicolor (L.) Moench]. Sorghum lines with preflowering drought tolerance tend to senesce under postflowering drought stress while sorghum lines with postflowering drought tolerance (the stay‐green trait) tend to be sensitive to preflowering drought stress. Assessments of these phenotypes have been dependent on the incidence of drought stress conditions at specific developmental stages to achieve meaningful evaluation. Therefore, field‐based evaluations, most of which are visual, are notoriously difficult to perform and require growing lines in multiple locations across several years to achieve efficient selection for these traits. Here we report and demonstrate a correlation between leaf dhurrin [(S)‐p‐hydroxymandelonitrile‐β‐D‐glucopyranoside] contents and the level of stay‐green based on leaf and plant death ratings during postflowering drought stresses. Postflowering drought‐tolerant stay‐green sorghums had elevated dhurrin contents while preflowering drought‐tolerant sorghum lines exhibited lower dhurrin contents. Lines with intermediate leaf and plant death ratings exhibited intermediate dhurrin levels. Finally, dhurrin levels determined before flowering from sorghum grown under irrigated or dryland conditions were related to the degree of pre‐ or postflowering drought tolerance.
Simple three-level neutral point voltage balance control strategy based on SVPWM
Authors: Gong Bo , Cheng Shanmei , Qin Yi 
Published: March 2013

Abstract
The unbalance of the neutral point voltage is an inherent problem of three-level neutral-point-clamped (NPC) inverter, the effect of neutral point voltage balancing which is caused by voltage vector is analyzed, and the relationship of the voltage offset and neutral point voltage is studied in this paper. This paper proposes a novel neutral point balance strategy for three-level NPC inverter based on space vector pulse width modulation (SVPWM). A voltage offset is added to the modulation wave, and a closed-loop neutral point voltage balance control system is designed. In the control system, the dwelling time of synthesis voltage vectors for SVPWM is varied to solve the problem of the unbalance of the neutral point voltage, the sequence of the voltage vectors maintains unchanging. Simulation and experimental results show the neutral point voltage balancing control strategy based on SVPWM is effective.
Shunt power electronic buffer as active filter and energy flow controller
Authors: Szromba Andrzej 
Published: March 2013

Abstract
The considered shunt active power filter can be controlled not only to compensate non-active current in the supply source, but additionally to optimize energy flow between the source and the load. In such a case the filter shapes the source current to be active and simultaneously regulates its magnitude. The presented filter/buffer can operate properly even when the load contains AC or DC variable energy source of any characteristic. The device can optimize energy flow for a single load, but also for a group of loads as well. The distinctive feature of the employed control method of the filter/buffer is that certain changes of energy stored in the device are utilized as the source of information concerning the active current of the load. This control method is very flexible and can be implemented to nearly all structures of active filters, for DC, single- and multiphase circuits.
Computationally efficient method of simulation of an electric drive impact on the power grid
Authors: Beniak Ryszard , Gardecki Arkadiusz 
Published: March 2013

Abstract
This paper presents a computationally efficient method for modelling an impact of the converter drive on the power grid. The formalized variable structure method (FVSM) allows for comprehensive studies of the effect on the power grid and examining the relation between this effect and the number of drive and feeding line parameters. In order to obtain a comprehensive model along with the model of the power grid, the parameters that are applied originate from a drive of a coal-fired power station. These parameters have been determined based on assessment and estimation. The estimation process was conducted with the aid of a model that allows for the commutation of power electronic elements. The authors confirmed that the model was correct by comparing empirical and theoretical voltage and current waveforms. Harmonic content of the voltage and current in the power grid which feeds the drive are considered to be the measure of the converter drive impact on the power grid. The standard method for the reduction of a harmonic content in the voltage and current involves the application of line reactors and distribution or converter transformers. As an example, the authors determine the impact of the drive on the power grid with respect to the adopted parameters of the line reactor. This example presents FVSM abilities with regard to simulation of complex systems that contain power grid components and converter drives.
Optimal location of interline power flow controller in a power system network using ABC algorithm
Authors: Sreejith S. , Psimon Sishaj , Selvan M.P. 
Published: March 2013

Abstract
This paper proposes a methodology based on installation cost for locating the optimal position of interline power flow controller (IPFC) in a power system network. Here both conventional and non conventional optimization tools such as LR and ABC are applied. This methodology is formulated mathematically based on installation cost of the FACTS device and active power generation cost. The capability of IPFC to control the real and reactive power simultaneously in multiple transmission lines is exploited here. Apart from locating the optimal position of IPFC, this algorithm is used to find the optimal dispatch of the generating units and the optimal value of IPFC parameters. IPFC is modeled using Power Injection (PI) model and incorporated into the problem formulation. This proposed method is compared with that of conventional LR method by validating on standard test systems like 5-bus, IEEE 30-bus and IEEE 118-bus systems. A detailed discussion on power flow and voltage profile improvement is carried out which reveals that incorporating IPFC into power system network in its optimal location significantly enhance the load margin as well as the reliability of the system.
Analysis of the electromagnetic response of complex dispersive material with the single-step wideband finite element method
Authors: Butryło Bogusław 
Published: March 2013

Abstract
The paper describes the formulation and implementation of the broadband finite element time domain algorithm. The presented formalism is valid to analysis of electromagnetic phenomena in linear, frequency selective materials. The complex profile of permittivity of materials is approximated using a set of the Lorentz resonance models. The solution of the integro-differential second order equation is obtained using a singlestep integration scheme and a recursive convolution algorithm. The discussed formulation enables to adopt the structure of the narrowband part as well as the phase of calculation of the convolution equations for the subsequent components. The properties of the algorithm are validated using a finite difference broadband algorithm.
A new method for evaluation of transformer drying process using transfer function analysis and artificial neural network
Authors: Firoozi Hormatollah , Bigdeli Mehdi 
Published: March 2013

Abstract
Since a few years ago, there is an increasing interest for utilization of transfer functions (TF) as a reliable method for diagnosing of mechanical faults in transformer structure. However, this paper aims to develop the application of TF method in order to evaluate the drying quality of active part during the manufacturing process of transformer. To reach this goal, the required measurements are carried out on 50 MVA 132 KV/33 KV power transformer when active part is placed in the drying chamber. Two different features extracted from the measured TFs are then used as the inputs to artificial neural network (ANN) to give an estimate for required time in drying process. Results show that this new represented method could well forecast the required time. The results obtained from this method are valid for all the transformers which have the same design.