bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment of liver function in thioacetamide‐induced rat acute liver injury using an empirical mathematical model and dynamic contrast‐enhanced MRI with Gd‐EOB‐DTPA
Authors: Saito Shigeyoshi , Moriyama Yuki , Kobayashi Shuichiro , Ogihara Ryota , Koto Daichi , Kitamura Akihiro , Matsushita Taro , Nishiura Motoko , Murase Kenya
Published: June 2012

Purpose:

To evaluate thioacetamide (TAA)‐induced acute liver injury in rats using an empirical mathematical model (EMM) and dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI) with gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd‐EOB‐DTPA).

Materials and Methods:

Eighteen rats were divided into three groups (normal control [n = 6], TAA [140] [n = 6], and TAA [280] groups [n = 6]). The rats of the TAA (140) and TAA (280) groups were intravenously injected with 140 and 280 mg/kg body weight (BW) of TAA, respectively, while those of the normal control group were intravenously injected with the same volume of saline. DCE‐MRI studies were performed using Gd‐EOB‐DTPA (0.025 mmol Gd/kg; 0.1 mL/kg BW) as the contrast agent 48 hours after TAA or saline injection. After the DCE‐MRI study, blood was sampled and serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were measured. We calculated the rate of contrast uptake (α), the rate of contrast washout (β), the elimination half‐life of relative enhancement (RE) (T1/2), the maximum RE (REmax), and the time to (REmax) (Tmax) from time‐signal intensity curves using EMM.

Results:

The REmax values in the TAA (140) groups and TAA (280) groups were significantly smaller than that in the normal control group. The Tmax value in the TAA (280) group was significantly greater than that in the normal control group. The β value in the TAA (280) group was significantly smaller than those in the normal control and TAA (140) groups, whereas there were no significant differences in β among groups. The T1/2 value in the TAA (280) group was significantly greater than those in the normal control and TAA (140) groups. The REmax, Tmax, β, and T1/2 values significantly correlated with AST and ALT.

Conclusion:

The EMM is useful for evaluating TAA‐induced acute liver injury using DCE‐MRI with Gd‐EOB‐DTPA. J. Magn. Reson. Imaging 2012; 36:1483–1489. © 2012 Wiley Periodicals, Inc.
Trends in extreme temperature indices in Austria based on a new homogenised dataset
Authors: Nemec Johanna , Gruber Christine , Chimani Barbara , Auer Ingeborg
Published: June 2012

Instrumental time series are often affected by inhomogeneities which can mask or amplify climate change signals. Various procedures for the detection and adjustment of breaks exist for monthly and annual time series. Homogenization methods on a daily basis are scarce and often disregard uncertainties accompanying the break adjustment. We present a complete homogenization procedure for daily extreme temperature series based on the break detection method PRODIGE and SPLIDHOM for break correction. Both parts of the homogenization rely on the existence of highly correlated reference stations. After the statistical comparison with neighbouring stations, detected breaks are verified and further localized by metadata. Uncertainties of the break adjustments are estimated by altering reference stations and by applying a bootstrapping technique providing an objective indication about the reliability of the homogenization.

The method was tested and applied to 71 time series of daily minimum (TN) and maximum temperatures (TX) in Austria covering the period 1948–2009. For some series homogenization was not possible due to large uncertainties in the adjustments or a lack of suitable reference series. In the remaining 57 TN and 54 TX series a total number of 139 breaks were detected. Seventy‐five percent of those breaks are documented in the metadata archive, with most of them being caused by station relocations and instrumentation changes. In general, the mean over the temperature dependent adjustments of all stations show a temperature reduction. However, the majority of breaks have mean amplitudes of less than 0.5 °C. A comprehensive analysis was performed on the new homogenized daily dataset, showing a widespread warming trend in both TN and TX series. The warming trend is in general amplified due to the homogenization. However, significant changes in the trend are only observed at very few stations. In autumn, however, the trend is reversed in many temperature based ‘climate change detection indices’. Copyright © 2012 Royal Meteorological Society
Hydroclimatic changes in a climate‐sensitive tropical region
Authors: Panda Dileep K. , Kumar A. , Singandhupe R. B. , Sahoo N.
Published: June 2012

In this study, the hydroclimatic variables of Orissa, a tropical region in eastern India, and the cyclonic disturbances over the Bay of Bengal were analysed to assess trends and variations using nonparametric statistical procedures. The trend results revealed pronounced warming pattern in the monthly maximum temperatures and cooling pattern in the monthly minimum temperatures for the period 1987–2001. The differential forcing mechanisms of greenhouse gases and aerosols were considered as a reason for the temperature extremes. For the period 1960–2003, significant upward shift was observed in June rainfall, particularly over the region where orography influences the rainfall. This study provides strong evidence suggesting the occurrence of abrupt shifts in the cyclonic disturbances over the Bay of Bengal. For the period 1901–2003, the monsoon depressions and cyclonic storms, which contribute a substantial amount of rainfall in Orissa and central India, exhibited significant downward abrupt shifts during 1971 and 1950, respectively. However, severe cyclonic storms in the post‐monsoon season showed significant upward shift during the 1961–1965 pentad. More cases of non‐significant decreasing trends were observed in the monsoon rainfall for the period 1980–2003 in spite of high inter‐annual variability. These trends may be attributed to the significant downward shift in the monsoon depression from 1983 onwards analysed for the period 1960–2003. Results also show that the observed trends are highly sensitive to the season of analysis and the period of records. Copyright © 2012 Royal Meteorological Society
The characteristics of seasonal‐scale droughts in Australia, 1911–2009
Authors: Gallant Ailie J. E. , Reeder Michael J. , Risbey James S. , Hennessy Kevin J.
Published: June 2012

Climatologies and variations in seasonal‐scale droughts in Australia are quantified using four indices representing the characteristics of the lower tails of rainfall and soil moisture distributions. These indices estimate variations in drought frequency, duration and intensity from 1911 to 2009 across Australia and for five large‐scale regions. Since 1911, large interdecadal variations in the characteristics of seasonal‐scale droughts have overlain trends towards less frequent, shorter and less severe droughts across much of Australia, with the strongest trends in northwest Australia. Regional exceptions include increases in seasonal‐scale drought frequency, duration and intensity in areas of southwest and southeast Australia. In parts of the west and southeast of the Murray–Darling Basin, the average duration of seasonal‐scale droughts, defined as successive seasons in drought, statistically significantly increased by between 10 and 69% during the second half of the 20th Century. Averaged across large‐scale regions in southeast and northwest Australia, decades with longer‐lasting and more intense soil moisture‐based seasonal droughts had statistically significantly higher actual evaporation compared with other decades. These were combined with modest rainfall deficits, suggesting that evaporation may be an important process for regulating drought duration or intensity in these regions. However, other hydroclimatic processes that were not assessed here likely also influence soil moisture, making attribution difficult. Copyright © 2012 Royal Meteorological Society
Analysis of polystyrene‐b‐polyisoprene copolymers by coupling of liquid chromatography at critical conditions to NMR at critical conditions of polystyrene and polyisoprene
Authors: Sinha Pritish , Hiller Wolf , Bellas Vasilios , Pasch Harald
Published: June 2012

For the investigation of the molecular heterogeneity of polystyrene‐b‐polyisoprene block copolymers, a chromatographic separation method, namely liquid chromatography at critical conditions was developed. This method was coupled on‐line with 1H‐NMR(where NMR stands for nuclear magnetic resonance) for the comprehensive analysis of the polystyrene‐b‐polyisoprene copolymers. The copolymers were synthesized by two different methods: sequential living anionic polymerization and coupling of living precursor blocks. While 1H‐NMR allows just for the analysis of the bulk chemical composition of the block copolymers, the coupling with liquid chromatography at critical conditions provides selective molar mass information on the polystyrene and polyisoprene blocks within the copolymers. The polyisoprene block molar mass is determined by operating at chromatographic conditions corresponding to the critical point of adsorption of polystyrene and size exclusion chromatography mode for polyisoprene. The molar mass of the polystyrene block is determined by operating at the critical conditions of polyisoprene. In addition to the molar mass of each block of the copolymers, the chemical composition distribution of the block copolymers was determined. By using the coupling of liquid chromatography at critical conditions to 1H‐NMR, one can also detect the homopolymers formed during synthesis. Finally the microstructure of the polyisoprene block in the copolymers was evaluated as a function of molar mass.
Influence of temperature on peak shape and solvent compatibility: Implications for two‐dimensional liquid chromatography
Authors: Haun Jakob , Teutenberg Thorsten , Schmidt Torsten C.
Published: June 2012

Solvent compatibility is a limiting factor for the success of two‐dimensional liquid chromatography (2‐D LC). In the second dimension, solvent effects can result in overpressures as well as in peak broadening or even distortion. A peak shape study was performed on a one‐dimensional high‐performance liquid chromatography (HPLC) system to simulate the impact of peak distorting solvent effects on a reversed‐phase second dimension separation operated at high temperatures. This study includes changes in injection volume, solute concentration, column inner diameter, eluent composition and oven temperature. Special attention was given to the influence of high temperatures on the solvent effects. High‐temperature HPLC (HT‐HPLC) is known to enhance second dimension separations in terms of speed, selectivity and solvent compatibility. The ability to minimise the viscosity contrast between the mobile phases of both dimensions makes HT‐HPLC a promising tool to avoid viscosity mismatch effects like (pre‐)viscous fingering. In case of our study, viscosity mismatch effects could not be observed. However, our results clearly show that the enhancement in solvent compatibility provided by the application of high temperatures does not include the elimination of solvent strength effects. The additional peak broadening and distortion caused by this effect is a potential error source for data processing in 2‐D LC.
Sinus hypoplasia precedes sinus infection in a porcine model of cystic fibrosis
Authors: Chang Eugene H. , Pezzulo Alejandro A. , Meyerholz David K. , Potash Andrea E. , Wallen Tanner J. , Reznikov Leah R. , Sieren Jessica C. , Karp Philip H. , Ernst Sarah , Moninger Thomas O. , Gansemer Nicholas D. , McCray Paul B. , Stoltz David A. , Welsh Michael J. , Zabner Joseph
Published: June 2012

Objectives/Hypothesis:

Chronic sinusitis is nearly universal in humans with cystic fibrosis (CF) and is accompanied by sinus hypoplasia (small sinuses). However, whether impaired sinus development is a primary feature of loss of the cystic fibrosis transmembrane conductance regulator (CFTR) or a secondary consequence of chronic infection remains unknown. Our objective was to study the early pathogenesis of sinus disease in CF.

Study Design:

Animal/basic science research.

Methods:

Sinus development was studied in a porcine CF model.

Results:

Porcine sinus epithelia expressed CFTR and exhibited transepithelial anion transport. Disruption of the CFTR gene eliminated both. Sinuses of newborn CF pigs were not infected and showed no evidence of inflammation, yet were hypoplastic at birth. Older CF pigs spontaneously developed sinus disease similar to that seen in humans with CF.

Conclusions:

These results define a role for CFTR in sinus development and suggest the potential of the CF pig as a genetic model of CF‐sinus disease in which to test therapeutic strategies to minimize sinus‐related CF morbidity.
Effect of laser textured dimples on the lubrication performance of cylinder liner in diesel engine
Authors: Yin Bifeng , Li Xiaodong , Fu Yonghong , Yun Wang
Published: June 2012

Laser surface texturing (LST) technique was utilised on a cylinder liner in a diesel engine. In order to analyse the effect of LST micro‐dimples on the lubrication and friction properties of cylinder liner–piston ring (CL–PR), we developed a new mixed lubrication model on the basis of the average Reynolds equation and asperity contacts equation. The model can consider the coupling effects between the surface roughness of non‐texturing regions and micro‐dimples and the synergistic effects of multi‐micro‐dimples. The results show that cylinder liner surface by LST can form effective hydrodynamic lubrication effect in most regions of the strokes, only near the dead points, the friction pair is in mixed lubrication state, asperity contact plays a major role in balancing the external load and the asperity friction force is obvious. The micro‐dimple parameters were optimised to obtain a better lubrication effect with the following optimised results: rp = 30–60 µm, Sp = 0.2–0.4 and e = 0.03–0.1. Copyright © 2012 John Wiley & Sons, Ltd.
Adhesion and tribological property of Cu nanoparticles‐doped hydrophobic polyelectrolyte multilayers
Authors: Yang Guangbin , Chen Xinhua , Zhang Zhanming , Song Shiyong , Yu Laigui , Zhang Pingyu
Published: June 2012

Hydrophobic polyelectrolyte multilayers (PEMs) doped with Cu nanoparticles and modified with fluoroalkylsilane were prepared by a series of reaction cycles, where the polyelectrolyte multilayers were constructed by alternate pipetting of the solutions of poly(diallyldimethylammonium chloride) and poly(sodium 4‐styrene sulfonate) onto a spinning substrate (quartz slide or silicon wafer), and resultant PEMs‐coated substrate was immersed in Cu2+ and NaBH4 solutions to allow nucleation of Cu nanoparticles. The relationship between the water wettability and tribological behavior of the as‐prepared hydrophobic PEMs was studied. Results show that the wettability of the hydrophobic PEMs can be controlled by properly adjusting the reaction cycle. The adhesion and tribological behavior of the Cu nanoparticles‐doped hydrophobic PEMs, excluding the one obtained at 12 reaction cycles, are closely related to their wettability. That is, the PEM film with stronger hydrophobicity has a lower surface energy, showing a lower friction and longer anti‐wear life. Copyright © 2012 John Wiley & Sons, Ltd.
Tribological properties of non‐ferrous coating lubricated with rapeseed oil containing lubricant additives
Authors: Feng Xin , Xia Yanqiu
Published: June 2012

With the increasing requirements of environmental protection, using lead, hexavalent chromium and other heavy metals will be prohibited in different surface coatings. In this paper, the non‐ferrous CrN coatings and the rapeseed oil were chosen as friction pair and biodegradable lubricant. The tribology properties were investigated using SRV‐IV reciprocating friction wear test. The worn surface of CrN coatings was observed and analysed using scanning electron microscopy and X‐ray photoelectron spectroscopy. The results indicate that the rapeseed oil containing 1 wt.% MoZn (MoDTC (molybdenum dithiocarbamate) + ZnDTP (zinc dithiophosphate) (1 : 3)) exhibits better friction‐reducing properties than the rapeseed oil containing 1 wt.% PN (an amine salt of an alkoxylphosphate) additives, whereas the rapeseed oil containing 1 wt.% PN additive exhibits better wear resistance properties than the rapeseed oil containing 1 wt.% MoZn additives. This is partly attributed to the tribophysical and tribochemical reactions between the lubricant and the CrN coating sliding surfaces. Copyright © 2012 John Wiley & Sons, Ltd.
Biocompatible Poly(L‐lactide)/MWCNT Nanocomposites: Morphological Characterization, Electrical Properties, and Stem Cell Interaction
Authors: Lizundia Erlantz , Sarasua Jòsè Ramon , D'Angelo Francesco , Orlacchio Aldo , Martino Sabata , Kenny Josè Maria , Armentano Ilaria
Published: June 2012

The promising perspectives of PLLA‐based nanostructured biomaterials and their relevance in tissue engineering are reported. Nanocomposites based on PLLA and MWCNTs are developed with an MWCNT content ranging from 0 to 3 wt%. The electrical properties show a percolation threshold within a range of 0.21–0.33 wt% MWCNTs, and the conductivity increases by six orders of magnitude. The surface structure shows changes with the carbon nanotube concentration. The functional role of MWCNTs incorporation in terms of interactions with adult stem cells suggests that PLLA/MWCNT nanocomposites are suitable substrates for primary stem cell culture.

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Cellular Interactions of a Water‐Soluble Supramolecular Polymer Complex of Carbon Nanotubes with Human Epithelial Colorectal Adenocarcinoma Cells
Authors: Lee Yeonju , Geckeler Kurt E.
Published: June 2012

Water‐soluble, PAX‐loaded carbon nanotubes are fabricated by employing a synthetic polyampholyte, PDM. To investigate the suitability of the polyampholyte and the nanotubes as drug carriers, different cellular interactions such as the human epithelial Caco‐2 cells viability, their effect on the cell growth, and the change in the transepithelial electrical resistance in Caco‐2 cells are studied. The resulting complex is found to exhibit an effective anti‐cancer effect against colon cancer cells and an increased the reduction of the electrical resistance in the Caco‐2 cells when compared to the precursor PAX.

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One‐Step Approach for the Preparation of Organic‐Inorganic Janus‐Like Particles by Alkalization of Polystyrene‐block‐Poly(2‐vinylpyridine)/FeCl3Complex Micelles
Authors: Fu Xiaoning , Song Lianlian , Liu Jun , Li Xue , Zhang Xiaokai , Jia Yuxi
Published: June 2012

A novel approach to organic‐inorganic Janus‐like particles based on the alkalization process of polystyrene‐block‐poly(2‐vinylpyridine) (PS‐b‐P2VP) micelles containing FeCl3precursors in the P2VP cores in toluene is presented. It is found that by addition of a small amount of NaOH solution to a solution of the spherical PS‐b‐P2VP/FeCl3micelles, organic‐inorganic Janus‐like particles with a produced α‐FeOOH domain on one side and PS‐b‐P2VP block copolymers on the other can be prepared. The Janus‐like nanoparticles obtained by this facile approach may have potential application in biomedical areas.
Impaired self‐awareness of motor deficits in Parkinson's disease: Association with motor asymmetry and motor phenotypes
Authors: Maier Franziska , Prigatano George P. , Kalbe Elke , Barbe Michael T. , Eggers Carsten , Lewis Catharine J. , Burns Richard S. , Morrone‐Strupinsky Jeannine , Moguel‐Cobos Guillermo , Fink Gereon R. , Timmermann Lars
Published: June 2012

Background:

This study investigated impaired self‐awareness of motor deficits in nondemented, nondepressed Parkinson's disease (PD) patients during a defined clinical on state.

Methods:

Twenty‐eight PD patients were examined. Patients' self‐ratings and experts' ratings of patients' motor performance were compared. Patient–examiner discrepancies and level of impairment determined severity of impaired self‐awareness. Motor exam assessed overall motor functioning, hemibody impairment, and 4 motor phenotypes. Neuropsychological tests were also conducted.

Results:

Signs of impaired self‐awareness were present in 17 patients (60.7%). Higher severity of impaired self‐awareness correlated significantly with higher postural‐instability and gait‐difficulty off scores (r = .575; P = .001), overall motor off scores (r = .569; P = .002), and higher left hemibody off scores (r = .490; P = .008). In multiple linear regression analyses, higher postural‐instability and gait‐difficulty off scores remained as the only significant predictor of impaired self‐awareness severity.

Conclusions:

Postural instability and gait difficulties, disease severity, and right hemisphere dysfunction seem to contribute to impaired self‐awareness. © 2012 Movement Disorder Society
A new nerve coaptation technique using a biodegradable honeycomb‐patterned film
Authors: Okui Nobuyuki , Yamamoto Michiro , Fukuhira Yukako , Kaneko Hiroaki , Hirata Hitoshi
Published: June 2012

We developed a biodegradable poly‐lactide (PLA) film with a honeycomb‐patterned porous structure (honeycomb film). This study investigated the use of this film in neurorrhaphy. Three types of PLA film were tested following bilateral sciatic nerve transection and neurorrhaphy in 35 rats: 7‐ and 10‐μm thick honeycomb films, and cast film with no porous structures. Initially, following two‐stitch neurorrhaphy, 40 limbs (20 rats) underwent wrapping in 7‐ or 10‐μm honeycomb film, cast film, no wrapping, or extra two‐stitch neurorrhaphy (8 limbs each). Breaking strength was tested 2 days postoperatively. Another 30 limbs (15 rats) then underwent wrapping in 7‐ or 10‐μm honeycomb film, cast film, no wrapping, or sham operation (six limbs each). Histological and functional analyses were performed 6 weeks postoperatively. Breaking strength was significantly higher for the 10‐μm honeycomb film than for no wrapping (P = 0.013), although no significant difference was observed between the 7‐μm honeycomb and no wrapping (P = 0.085). Breaking strength for the cast film was almost equal to that for no wrapping (P = 0.994). Extra two‐stitch (four‐stitch) neurorrhaphy was significantly stronger than all groups, except the 10‐μm honeycomb group. No significant difference was observed between the 10‐μm honeycomb and the four‐stitch (P = 0.497). No negative effects on functional recovery were identified. No adhesions or inflammation were observed between the film and surrounding tissues in the honeycomb groups. Honeycomb film may offer a suitable reinforcing material for adhesion‐free neurorrhaphy. © 2012 Wiley Periodicals, Inc. Microsurgery 2012.
Prognostic scoring system for peripheral nerve repair in the upper extremity
Authors: Galanakos Spyridon P. , Zoubos Aristides B. , Mourouzis Iordanis , Ignatiadis Ioannis , Bot Arjan G.J. , Soucacos Panayotis N.
Published: June 2012

So far, predictive models with individualized estimates of prognosis for patients with peripheral nerve injuries are lacking. Our group has previously shown the prognostic value of a standardized scoring system by examining the functional outcome after acute, sharp complete laceration and repair of median and/or ulnar nerves at various levels in the forearm. In the present study, we further explore the potential mathematical model in order to devise an effective prognostic scoring system. We retrospectively collected medical record data of 73 cases with a peripheral nerve injury in the upper extremity in order to estimate which patients would return to work, and what time was necessary to return to the pre‐injury work. Postoperative assessment followed the protocol described by Rosén and Lundborg. We found that return to pre‐injury work can be predicted with high sensitivity (100%) and specificity (95%) using the total numerical score of the Rosén and Lundborg protocol at the third follow‐up interval (TS3) as well as the difference between the TS3 and the total score at second follow‐up interval (TS2). In addition, the factors age and type of injured nerve (median, ulnar, or combined) can determine the time of return to work based on a mathematical model. This prognostic protocol can be a useful tool to provide information about the functional and social prospects of the patients with these types of injuries. © 2012 Wiley Periodicals, Inc. Microsurgery, 2013.
Decay properties of solutions to the incompressible magnetohydrodynamics equations in a half space
Authors: Han Pigong , He Cheng
Published: June 2012

We consider the asymptotic behavior of the strong solution to the incompressible magnetohydrodynamics (MHD) equations in a half space. The Lr‐decay rates of the strong solution and its derivatives with respect to space variables and time variable, including the L1 and L ∞  decay rates of its first order derivatives with respect to space variables, are derived by using Lq − Lr estimates of the Stokes semigroup and employing a decomposition for the nonlinear terms in MHD equations. In addition, if the given initial data lie in a suitable weighted space, we obtain more rapid decay rates than observed in general. Similar results are known for incompressible Navier–Stokes equations in a half space under same assumption. Copyright © 2012 John Wiley & Sons, Ltd.
Small data global well‐posedness for the nonlinear wave equation with nonlocal nonlinearity
Authors: Cheng Xing , Gao Yanfang
Published: June 2012

In this paper, we investigate the Cauchy problem of the nonlinear wave equation , where V(u) = μ|·|−γ ∗ |u|2, , 0 < γ < min(4, n) and n ≥ 3. We prove small data global well‐posedness for the radial data and for the general data with angular regularity. We also give an improved result of the Hartree equation with negative critical regularity. Copyright © 2012 John Wiley & Sons, Ltd.
Nonlinear anisotropic parabolic equations in with locally integrable data
Authors: Mokhtari Fares
Published: June 2012

In this paper, we prove existence and regularity of weak solutions for a class of nonlinear anisotropic parabolic problems in with locally integrable data. Our approach is based on the anisotropic Sobolev inequality, a smoothness, and compactness results. Copyright © 2012 John Wiley & Sons, Ltd.
On the essential spectrum of quantum waveguides
Authors: Rabinovich V.S. , Castillo‐Pérez R. , Urbano‐Altamirano F.
Published: June 2012

The main aim of the paper is the study of essential spectra of electromagnetic Schrödinger operators with variable potentials in cylindric domains , where is a bounded domain with a smooth boundary provided by admissible boundary conditions. Applying the limit operators method, we obtain explicit estimates of the essential spectrum for a wide class of quantum waveguides.

We also consider a numerical example of calculations of the discrete spectrum of horizontally stratified quantum waveguides applying a method of the decomposition of solutions of spectral problems for one‐dimensional Schrödinger operators as a power series with respect to the spectral parameter. Copyright © 2012 John Wiley & Sons, Ltd.
Taurine is a liver X receptor‐α ligand and activates transcription of key genes in the reverse cholesterol transport without inducing hepatic lipogenesis
Authors: Hoang Minh‐Hien , Jia Yaoyao , Jun Hee‐jin , Lee Ji Hae , Hwang Kwang‐Yeon , Choi Dal‐Woong , Um Soo‐Jong , Lee Boo‐Yong , You Sang‐Guan , Lee Sung‐Joon
Published: June 2012

Scope

Taurine, which is abundant in seafood, has antiatherogenic activities in both animals and humans; however, its molecular target has been elusive. We examined whether taurine could activate liver X receptor‐α (LXR‐α), a critical transcription factor in the regulation of reverse cholesterol transport in macrophages.

Methods and results

Taurine bound directly to LXR‐α in a reporter gene assay, time‐resolved fluorescence resonance energy transfer analysis, and limited protease digestion experiment. Macrophage cells incubated with taurine showed reduced cellular cholesterol and induced medium cholesterol in a dose‐dependent manner with the induction of ATP‐binding cassette transporter A1 and G gene and protein expression. In hepatocytes, taurine significantly induced Insig‐2a levels and delayed nuclear translocation of the sterol regulatory element‐binding protein 1 (SREBP‐1) protein, resulting in a dose‐dependent reduction in the cellular lipid levels without inducing the expression of fatty acid synthesis genes.

Conclusion

Taurine is a direct LXR‐α ligand, represses cholesterol accumulation, and modulates the expression of genes involved in reverse cholesterol transport in macrophages, without inducing hepatic lipogenesis. The induction of Insig‐2a suppressed the nuclear translocation of SREBP‐1c.
In vitro and in vivo structure and activity relationship analysis of polymethoxylated flavonoids: Identifying sinensetin as a novel antiangiogenesis agent
Authors: Lam In Kei , Alex Deepa , Wang You‐Hua , Liu Ping , Liu Ai‐Lin , Du Guan‐Hua , Yuen Lee Simon Ming
Published: June 2012

Scope

Polymethoxylated flavonoids are present in citrus fruit in a range of chemical structures and abundance. These compounds have potential for anticarcinogenesis, antitumor, and cardiovascular protective activity, but the effect on angiogenesis has not been well studied.

Methods and results

Human umbilical vein endothelial cells (HUVECs) in vitro and zebrafish (Danio rerio) in vivo models were used to screen and identify the antiangiogenesis activity of seven polymethoxylated flavonoids; namely, hesperetin, naringin, neohesperidin, nobiletin, scutellarein, scutellarein tetramethylether, and sinensetin. Five, excluding naringin and neohesperidin, showed different degrees of potency of antiangiogenesis activity. Sinensetin, which had the most potent antiangiogenesis activity and the lowest toxicity, inhibited angiogenesis by inducing cell cycle arrest in the G0/G1 phase in HUVEC culture and downregulating the mRNA expressions of angiogenesis genes flt1, kdrl, and hras in zebrafish.

Conclusion

The in vivo structure–activity relationship (SAR) analysis indicated that a flavonoid with a methoxylated group at the C3′ position offers a stronger antiangiogenesis activity, whereas the absence of a methoxylated group at the C8 position offers lower lethal toxicity in addition to enhancing the antiangiogenesis activity. This study provides new insight into how modification of the chemical structure of polymethoxylated flavonoids affects this newly identified antiangiogenesis activity.
Vitamin E decreases extra‐hepatic menaquinone‐4 concentrations in rats fed menadione or phylloquinone
Authors: Farley Sherry M. , Leonard Scott W. , Labut Edwin M. , Raines Hannah F. , Card David J. , Harrington Dominic J. , Mustacich Debbie J. , Traber Maret G.
Published: June 2012

Scope

The mechanism for increased bleeding and decreased vitamin K status accompanying vitamin E supplementation is unknown. We hypothesized that elevated hepatic α‐tocopherol (α‐T) concentrations may stimulate vitamin K metabolism and excretion. Furthermore, α‐T may interfere with the side chain removal of phylloquinone (PK) to form menadione (MN) as an intermediate for synthesis of tissue‐specific menaquinone‐4 (MK‐4).

Methods and results

In order to investigate these hypotheses, rats were fed phylloquinone (PK) or menadione (MN) containing diets (2 μmol/kg) for 2.5 weeks. From day 10, rats were given daily subcutaneous injections of either α‐T (100 mg/kg) or vehicle and were sacrificed 24 h after the seventh injection. Irrespective of diet, α‐T injections decreased MK‐4 concentrations in brain, lung, kidney, and heart; and PK in lung. These decreases were not accompanied by increased excretion of urinary 5C‐ or 7C‐aglycone vitamin K metabolites, however, the urinary α‐T metabolite (α‐CEHC) increased ≥100‐fold. Moreover, α‐T increases were accompanied by downregulation of hepatic cytochrome P450 expression and modified expression of tissue ATP‐binding cassette transporters.

Conclusion

Thus, in rats, high tissue α‐T depleted tissue MK‐4 without significantly increasing urinary vitamin K metabolite excretion. Changes in tissue MK‐4 and PK levels may be a result of altered regulation of transporters.
Low power consumption thermo‐optic switch based on DR1/PMMA
Authors: Cao Zijian , Yan Yunfei , Meng Jie , Jin Lin , Zhang Daming
Published: June 2012

A new kind of thermo‐optic switch based on DR1/PMMA is proposed. This material has good cost‐performance, large thermo‐optic coefficient, and other advantages for electro‐optic devices because of the nonlinear chromophore DR1. Based on Mach‐Zehnder interferometer, this switch adopts the square waveguide structure and polymer silica hybrid configuration to adjust the optical field distribution for more thermo‐optic operation efficiency. A coplanar waveguide heater ensures the high frequency response of electrode and the ground electrode as a heat sink can prevent the thermo power accumulated. The total length of the device is 3.5 cm including the 1.5‐cm heater. The test results show that the extinction ratio is 21 dB, and the power consumption is less than 13 mW. The measured switching time is less than 0.9 ms. This work provides foundation for design and fabrication of electro‐optic and thermo‐optic hybrid integrated devices. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2163–2165, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26996
Compact printed coplanar waveguide‐fed ultra‐wideband antenna with multiple notched bands
Authors: Taheri Mohammad Mehdi Samadi , Hassani Hamid R. , Nezhad Sajad Mohammad Ali
Published: June 2012

A compact multiband‐notched printed ultra‐wideband (UWB) coplanar waveguide (CPW)‐fed slot antenna is presented. The band notched characteristic is achieved by creating quarter‐wavelength stubs in the ground plane. These stubs act as stop‐band filters along the feed line over certain narrow frequency bands. Addition of each stub to the antenna structure creates an extra independent notch band. Antenna with single, dual, triple, quadruple, and penta notch bands can be created by this technique. The notch bands can be chosen from practical frequency bands such as 3.5 GHz WiMAX, 5.2 and 5.8 GHz WLAN, 7.25–7.75 GHz for the downlink of X‐band satellite communication systems, and ITU at 8.2 GHz band all within the UWB range. Each of the notch bands can be tuned in frequency independently. The antenna has a small size (24 × 27 × 0.8 mm3), and almost stable omnidirectional radiation pattern. The prototype of the antenna is fabricated, and the measured results are in good agreement with the simulations. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2121–2126, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26998
The effects of air stacked on reconfigurable quadratic slots antenna for WiMAX and 4G applications
Authors: Jamlos M. F. , Rahman T. A. , Kamarudin M. R. , Malek M. F. , Jusoh M.
Published: June 2012

This research presents the effects of an air‐stacked configuration on the novel reconfigurable quadratic antenna. The proposed antenna is made feasible by using a feeding line, PIN diodes, and an aperture coupled feeding structure with quadratic slots shape and varied levels of air‐stacked sequence: 0, 5, 10, 15, and 20 mm. Instead of a quadratic slot, it is proven through simulations and measurements that the performance of four types of radiation patterns is greatly influenced by the air‐stacked structure at 2.3 GHz operating frequency. The activation of certain PIN diode switch configuration enables the variety of outcomes of the radiation patterns with different beamwidths and gains at a single time. This novel antenna is competent to shape its radiated beam in terms of gain and half‐power beamwidth up to 12.92 dB (≈ 13 dB) and 110.9°, respectively, with 81.76% of efficiency. The air‐stacked formation also affords a good quality factor, Q, as low as less than 1 (<1) to indirectly indicate that the quality of the antenna in terms of efficiency and gain is outstanding. The proposed antenna has a massive potential to be deployed in WiMAX application in future. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2139–2144, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27000
A compact printed UWB antenna with triple band‐notched characteristics
Authors: Xu Jie , Wang Guangtao
Published: June 2012

In this letter, a compact printed ultra‐wideband antenna with triple band‐notched characteristics is presented. The antenna consists of a circular radiating patch and a 50‐Ω coplanar waveguide transmission line. The triple band‐notched characteristics are obtained by etching two C‐shaped slots on the radiating patch and a pair of symmetric C‐shaped slots on the ground. Simulated and measured results show that this antenna could operate from 2.8 to 12.6 GHz with stable radiation patterns, except triple notched bands at 3.43–3.65, 4.95–5.25, and 5.36–5.85 GHz for rejecting the WiMAX and wireless local area network signals. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2146–2150, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27004
A 60 GHz power amplifier using lange couplers in GaAS 0.15 μm pHEMT process
Authors: Wu Ming‐Wei , Chiang Yen‐Chung
Published: June 2012

This letter proposes a 60 GHz power amplifier (PA) fabricated in GaAs 0.15μm pHEMT process technology.A three‐stage topology with Lange couplers is adopted. The measured results show that the proposed PA achieves a gain of 23 dB and a saturated output power of 14.46 dBm at 63.4 GHz, and its peak power‐added efficiency is 6.9%. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2150–2153, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27015
UWB equiangular spiral antenna for 7.5–40 GHz
Authors: Chernobrovkin R. , Ivanchenko I. , Pischikov V. , Popenko N.
Published: June 2012

The ultrawide‐band antenna with original transformer providing the required electromagnetic matching of the coaxial cable with the small‐size single‐arm equiangular spiral antenna is proposed. The measured input reflection coefficient of the small‐size spiral antenna is less than −10 dB within the frequency band from 7.5 to 40 GHz. The near‐fields, radiation patterns and axial ration within the impedance antenna bandwidth are presented and discussed. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2190–2194, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27018
Loading artificial magnetic conductor and artificial magnetic conductor absorber with negative impedance convertor elements
Authors: Ding Yuan , Fusco Vincent
Published: June 2012

The general properties of a frequency selective surface loaded with negative impedance converter (NIC)‐based active loads are discussed from a theoretical perspective.The stability problem associated with NIC circuits embedded in artificial magnetic conductor (AMC) and AMC absorber applications is studied using pole‐zero analysis. The requirements and constraints for achieving stable operation with enhanced bandwidth using negative capacitance as realized by a floating NIC network are derived. Furthermore, it is shown that it is nearly impossible to simultaneously implement a negative capacitor and a negative inductor to such structures. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2111–2114, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27019
UWB printed sectoral monopole antenna with dual polarization
Authors: Ray K. P. , Thakur S.S. , Deshmukh R. A.
Published: June 2012

A printed sectoral monopole antenna with ultra wide bandwidth has been proposed. This configuration is formed by chopping off a quarter part of a circular printed disc. The ultra wide bandwidth has been obtained in the frequency range from 1.84 to 11.82 GHz with dual polarization radiation patterns. The experimental and simulated results for this proposed antenna are presented, which are in agreement. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2066–2070, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27039
Ultrawideband monopole antenna for use in a circular cylindrical microwave imaging system
Authors: Halili Khodadad , Ojaroudi Mohammad , Ojaroudi Nasser
Published: June 2012

A novel ultrawideband printed monopole antenna for use in a circular cylindrical microwave imaging system is presented.The proposed antenna consists of a square radiating patch and a modified ground plane with an open circuit structure slit and an inverted π‐shaped parasitic structure, which provides a wide usable fractional bandwidth of more than 130% (2.91–14.72 GHz). By cutting an open circuit structure in the ground plane and also by inserting an inverted π‐shaped parasitic structure in the ground plane, additional resonances at 11.5 and 14.2 GHz are excited and hence much wider impedance bandwidth can be produced, especially at the higher band. Unlike other antennas reported in the literature to date, the proposed antenna displays a good omnidirectional radiation pattern even at higher frequencies, and also its radiation efficiency is greater than 87% across the entire radiating band. The designed antenna has a small size of 12 × 18 mm2. Simulated and measured results are presented to validate the usefulness of the proposed antenna structure for circular cylindrical microwave imaging systems. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2202–2205, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27041
Comparing model‐based and model‐free analysis methods for QUASAR arterial spin labeling perfusion quantification
Authors: Chappell Michael A. , Woolrich Mark W. , Petersen Esben T. , Golay Xavier , Payne Stephen J.
Published: June 2012

Amongst the various implementations of arterial spin labeling MRI methods for quantifying cerebral perfusion, the QUASAR method is unique. By using a combination of labeling with and without flow suppression gradients, the QUASAR method offers the separation of macrovascular and tissue signals. This permits local arterial input functions to be defined and “model‐free” analysis, using numerical deconvolution, to be used. However, it remains unclear whether arterial spin labeling data are best treated using model‐free or model‐based analysis. This work provides a critical comparison of these two approaches for QUASAR arterial spin labeling in the healthy brain. An existing two‐component (arterial and tissue) model was extended to the mixed flow suppression scheme of QUASAR to provide an optimal model‐based analysis. The model‐based analysis was extended to incorporate dispersion of the labeled bolus, generally regarded as the major source of discrepancy between the two analysis approaches. Model‐free and model‐based analyses were compared for perfusion quantification including absolute measurements, uncertainty estimation, and spatial variation in cerebral blood flow estimates. Major sources of discrepancies between model‐free and model‐based analysis were attributed to the effects of dispersion and the degree to which the two methods can separate macrovascular and tissue signal. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
Impact of aging on the progression of neuropathy after liver transplantation in transthyretin Val30Met amyloidosis
Authors: Koike Haruki , Hashimoto Rina , Tomita Minoru , Kawagashira Yuichi , Iijima Masahiro , Nakamura Tomohiko , Watanabe Hirohisa , Kamei Hideya , Kiuchi Tetsuya , Sobue Gen
Published: June 2012

Introduction: Information related to the long‐term follow‐up of neuropathy in patients with familial amyloid polyneuropathy after liver transplantation is still scarce.Methods: We describe the neuropathic features of 3 patients with the transthyretin Val30Met mutation. Each patient underwent liver transplantation at an early stage of neuropathy, as indicated by the absence of motor dysfunction and relative preservation of myelinated fibers in sural nerve biopsy specimens.Results: Although the patient with late‐onset disease (at age 60 years) presented with the least amount of amyloid deposition, he had neuropathic progression after liver transplantation. An older early‐onset (at age 40 years) patient reported a slight exacerbation of both somatic and autonomic neuropathic symptoms 10 years after transplantation. However, the younger early‐onset (at age 28 years) patient did not exhibit characteristics suggestive of neuropathy 7 years after transplantation.Conclusion: Aging may determine the progression of neuropathy after liver transplantation. Muscle Nerve, 2012
THE POLITICAL ECONOMY OF GREEN GROWTH: CASES FROM SOUTHERN AFRICA
Authors: Resnick Danielle , Tarp Finn , Thurlow James
Published: June 2012

The concept of Green Growth implies that a wide range of developmental objectives, such as job creation, economic prosperity and poverty alleviation, can be easily reconciled with environmental sustainability. This article, however, argues that rather than being win–win, Green Growth is similar to most types of policy reforms that advocate the acceptance of short‐term adjustment costs in the expectation of long‐term gains. In particular, Green Growth policies often encourage developing countries to redesign their national strategies in ways that might be inconsistent with natural comparative advantages and past investments. In turn, there are often sizeable anti‐reform coalitions whose interests may conflict with a Green Growth agenda. We illustrate this argument by using case studies of Malawi, Mozambique and South Africa, which are engaged in development strategies that involve inorganic fertilizers, biofuel production and coal‐based energy, respectively. Each of these countries is pursuing an environmentally suboptimal strategy but nonetheless addressing critical development needs, including food security, fuel and electricity. We show that adopting a Green Growth approach would not only be economically costly but also generate substantial domestic resistance, especially among the poor. Copyright © 2012 John Wiley & Sons, Ltd.
ENVIRONMENTAL MAINSTREAMING: THE ORGANISATIONAL CHALLENGES OF POLICY INTEGRATION
Authors: Nunan Fiona , Campbell Adrian , Foster Emma
Published: June 2012

Mainstreaming has been adopted internationally as a key approach to promoting environmental concerns and opportunities in national plans and strategies, as well as in sectoral policies and plans. As the climate change response begins to look to mainstreaming as a way forward for adaptation, lessons should be learnt from the environmental mainstreaming experience on the forms of organisational arrangements adopted. From an analysis of experience in a range of southern countries, the article uses a framework of vertical and horizontal organisational arrangements for policy integration to assess which organisational forms have been adopted and with what implications. The review found a mix of experience, with strong political commitment seeming to support a vertical approach to organisational integration, with a lead, overarching agency, as opposed to a more horizontal approach with the ministry responsible for the environment leading. The theory and analysis suggests that a more promising approach to facilitate effective mainstreaming might be to combine elements of vertical and horizontal arrangements, at least over the medium term, where there is strong central commitment and capacity for sustained implementation. Copyright © 2012 John Wiley & Sons, Ltd.