bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessment of the Ecological Status of Streams in Two Carpathian Subregions
Authors: Krno Il'ja , Šporka Ferdinand , Pastuchová Zuzana , Derka Tomáš , Čiamporová‐Zaťovičová Zuzana , Bulánková Eva , Hamerlík Ladislav , Illéšová Daniela 
Published: August 2007

AbstractA multimetric assessment system was developed to determine the ecological status of two types of stream in the Carpathian ecoregion following the requirements of the WFD. The organic pollution gradient was defined using Canonical Correspondence Analysis. Classification based on physical, chemical and biological data divided the tested sites into two stream types with subsequent grouping into several ecological quality classes. From all the metrics tested, 17 for the East Carpathian streams and 15 for the West Carpathian streams, from seven metric categories, were included in the resulting multimetric index. Different kinds of response to degradation (linear, unimodal, exponential) were observed. The Saprobic index (Zelinka and Marvan), Rheoindex (Banning, with abundance classes) and Index of Biocenotic region, showed the best discriminatory ability for both stream types. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A ring filter switch for a low loss wideband and very sharp bandstop filter
Authors: Ahn Hee‐Ran , Kim Bumman 
Published: August 2007

AbstractA ring‐filter switch is suggested for a low loss wideband filter with on‐state and very sharp bandstop filter with off‐state. It consists of a ring filter and a switching diode. The ring filter is a wideband filter but a band‐stop filter with a certain condition. The fact can be used as a switch. To verify it, a microstrip ring‐filter switch is fabricated and measured at a center frequency of 3 GHz. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2828–2830, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22828
Left‐handed behavior in a microstrip line loaded with squared split‐ring resonators and an EBG pattern
Authors: Navarro‐Cía M. , Falcone F. , Beruete M. , Arnedo I. , Illescas J. , Marcotegui A. , Laso M.A.G. , Lopetegi T. 
Published: August 2007

AbstractCombining an electromagnetic band‐gap structure (EBG) and squared split‐ring resonators (SSRRs) in a planar microstrip line circuit, negative values of electric permittivity and magnetic permeability can be obtained. This phenomenon arises thanks to the negative permeability of the SSRR particles when they operate in the vicinity of their quasi‐static resonance frequency, and the negative permittivity due to the behavior of the EBG structure within the rejected frequency band. Therefore, a novel approach is presented in this article to synthesize a left‐handed media in microstrip technology. Full wave simulation results as well as measurement results from a fabricated prototype confirm the left‐handed behavior of the interaction. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2689–2692, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22841
A coplanar waveguide fed monopole ultra‐wideband antenna having band‐notched frequency function by two folded‐striplines
Authors: Lee Sang‐Ho , Baik Jung‐Woo , Kim Young‐Sik 
Published: August 2007

AbstractA compact coplanar waveguide fed monopole ultra‐wideband antenna having a frequency‐notch function is proposed. The notched frequency band can be achieved by including the two L‐shape striplines in the bottom of the substrate. The designed antenna has a notch band of 5.10–6.25 GHz while 10 dB return loss is ranged from 3.04 to 12.0 GHz. The measured return loss, radiation patterns, and gains are presented. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2747–2750, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22852
Synthesis of polystyrene brush on multiwalled carbon nanotubes treated with KMnO4 in the presence of a phase‐transfer catalyst
Authors: Kim Myunghun , Hong Chang Kook , Choe Soona , Shim Sang Eun 
Published: August 2007

AbstractMultiwalled carbon nanotubes (MWNTs) were effectively functionalized with KMnO4 in the presence of a phase‐transfer catalyst at room temperature. The hydroxyl functionalized MWNTs were reacted with a vinyl‐group carrying silane‐coupling agent and the terminal vinyl groups were used to fabricate polystyrene (PS) brushes by solution polymerization. Finally, PS‐encapsulated MWNTs were obtained. The synthesis results were verified from FT‐Raman, thermal gravimetric analysis, energy dispersive X‐ray analysis, and transmission electron microscope. PS‐encapsulated MWNTs had much improved dispersion stability in hydrophobic medium, toluene since grafted hydrophobic PS interacts with media and has improved compatibility. This functionalization technique would provide a facile route to prepare various polymer brushes on the surface of MWNTs to improve the dispersion of MWNTs for potential applications. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4413–4420, 2007
New conjugated polymers comprising ortho‐phenylazonaphthols: Synthesis and chromogenic behaviors
Authors: Choi Moon Soo , Lee Jung Hyo , Kim Dong Wook , Lee Taek Seung 
Published: August 2007

AbstractA new series of poly(ortho‐phenylazonaphthol) derivatives linked with a phenylene or fluorene repeat unit was synthesized using the Suzuki cross‐coupling reaction and characterized. The synthesized polymers can be categorized by their structures, with a free hydroxyl group and with a t‐Boc‐blocked hydroxyl group, which exhibited completely different UV‐vis absorption properties according to the allowed or forbidden tautomerism. In both cases, a pronounced color change to deep violet (bathochromic shift) was induced upon exposure to fluoride anion, presumably because of electron transfer between the hydroxyl group and the fluoride anion. Interestingly, the chromogenic pattern could be produced directly by UV irradiation through a photomask on the flexible nanofiber web electrospun from poly(methyl methacrylate) blended with t‐Boc‐protected Polymer 8 and photoinduced acid generator. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4430–4440, 2007
Synthesis and chiroptical properties of optically active poly(ethynylcarbazole) derivatives: Substituent effect on the helix formation
Authors: Sanda Fumio , Kawasaki Ritsuya , Shiotsuki Masashi , Masuda Toshio 
Published: August 2007

AbstractNovel chiral acetylene monomers containing carbazole, 2‐ethynyl‐9‐[(S)‐2‐methylbutoxycarbonyl]carbazole (1), 3‐ethynyl‐9‐[(S)‐2‐methylbutoxycarbonyl]carbazole (2), 2‐ethynyl‐9‐[(S)‐2‐methylbutyl]carbazole (3), and 2‐ethynyl‐9‐[(S)‐4‐methylhexyl]carbazole (4) were synthesized and polymerized with [(nbd)RhCl]2Et3N. The corresponding polyacetylenes with number‐average molecular weights ranging from 68,700 to 310,000 were obtained in good yields. Poly(1) exhibited a large specific rotation and an intense Cotton effect in toluene, indicating that it formed a helix with predominantly one‐handed screw sense, while the other three polymers showed no evidence for taking a helical structure. Poly(1) largely decreased the CD intensity upon heating from −10 to 60 °C. Poly(1) showed a Cotton effect in film state in a manner similar to solution state. No chiral amplification was observed in the copolymerization of 1 with achiral 2‐ethynyl‐9‐tert‐butoxycarbonylcarbazole (5). © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4450–4458, 2007
Living cationic ring‐opening polymerization of five‐membered cyclic dithiocarbonate controlled by neighboring group participation of carbamate group
Authors: Motokucho Suguru , Sudo Atsushi , Endo Takeshi 
Published: August 2007

AbstractA five‐membered cyclic dithiocarbonate having phenylcarbamate moiety 1 underwent cationic ring‐opening polymerization by using methyl trifluoromethanesulfonate as an initiator in nitrobenzene at 60 °C. Both of the corresponding first‐order kinetic plot and conversion‐molecular weight plot showed linearity to suggest the living fashion of the polymerization, which was then supported by two‐stage polymerization experiment. The living fashion as well as the regioselective formation of the repeating unit suggested significant contribution of the neighboring group participation of the carbamate group to form a stabilized cationic propagating end, of which structure was confirmed by performing an equimolar reaction of 1 and methyl trifluoromethanesulfonate with analyzing the resulting species by NMR spectroscopy. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4459–4464, 2007
Hyperbranched luminescent polyfluorenes containing aromatic triazole branching units
Authors: Tsai Lin‐Ren , Chen Yun 
Published: August 2007

AbstractUsing a new aromatic 1,2,4‐triazole branching monomer (4.8–13.3 mol %), three hyperbranched polyfluorenes (P2–P4) were synthesized by the Suzuki coupling reaction to investigate the structural effect on optoelectronic properties. Poly(9,9‐dihexylfluorene) (P1) was also prepared for comparative investigation. Their weight‐average molecular weights and polydispersity indices are in the range of 1.16 × 104 to 5.9 × 104 and 1.49–2.25, respectively. Optical properties, both in solution and film state, were investigated using absorption and photoluminescence (PL) spectra. In film state, the absorption and PL spectra peaked at 377–392 and 424–425 nm, respectively, blue‐shift with increasing triazole concentration. Furthermore, a linear relationship between 1/λmax,abs and 1/(1 − ntriazole) is correlated (n: molar fraction), indicating a smooth decrease in conjugation length by incorporation of the branch unit. The P4 containing 13.3 mol % triazole reveals stable blue emission even at 150 °C (in air). The HOMO and LUMO levels of P2–P4, estimated from cyclic voltammograms, are −5.69, −5.73, −5.78 eV and −2.63, −2.64, −2.63 eV, respectively. The maximal brightness (current efficiency) of the electroluminescent devices (ITO/PEDOT:PSS/P2–P4/Ca/Al) improves from 828 cd/m2 (0.19 cd/A) to 2054 cd/m2 (0.46 cd/A) with increasing triazole concentration. The results suggest that incorporation of aromatic 1,2,4‐triazole branch units is an effective way to improve annealing stability and EL performance of polyfluorenes. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4465–4476, 2007
Air Current Segregation of Alumina Powder
Authors: Zigan Stefan , Thorpe Rex B. , Tuzun Ugur , Enstad Gisle G. 
Published: August 2007

AbstractThis paper outlines the industrial problem of air current segregation in alumina storage silos which occurs with the handling of the feedstock alumina in aluminium plants and investigates the parameters that affect the severity of the segregation. Bates [1] stated that the feeding rate influences segregation which we can confirm with own experimental findings. Higher powder flow rates tend to reduce air current segregation. Cooper et al. [2] pointed out that the air extraction rate affects the content of fine particles (dust) in the circulating air currents and we confirm his finding. The importance of the effect of different feeding rates on air current segregation was discovered in a two dimensional apparatus. The investigation of the influence of air extraction rate was realised in a cylindrical silo. Both experiments show a strong relationship between the strength of the particle‐air flow in the silo and air current segregation. It is found that an increase of the powder feeding rate or the air extraction rate reduces air current segregation in the experimental equipment. The aim of our experiments was to find all significant parameters and to apply dimensional analysis to develop a method which scales the findings from small scale experiments to large industrial alumina silos. Five dimensionless groups were obtained, which is unwieldy. To reduce the number of dimensionless groups, physical properties were lumped into the terminal velocity. This simplified approach gives three dimensionless groups. Experiments in a water model and an air model justify more research using this simplified scaling method.
Solubility of linoleic acid in aqueous solutions and its reaction with water
Authors: Mabrouk Ahmed Fahmy , Dugan L. R. 
Published: August 2007

AbstractIn a study of stable emulsions of linoleic acid in 0.1M‐KH2PO4/Na2HPO4 buffer solutions prepared by sonic vibrations, the influence of linoleic acid on pH was manifested in buffer solutions of pH 8.00 and decreased gradually till it became negligible in pH 4.50. This change in pH values was due to differences in solubility of linoleic acid in the buffer solutions.Ultraviolet spectra of soluble linoleic acid in buffer solutions indicated the presence of conjugated dienes, which increased with the increasing of the pH of the system.Unbuffered aqueous emulsions of linoleic acid had a pH value which ranged between 4.69 and 5.10. Saturated aqueous solutions, obtained by high‐speed centrifugation, had concentrations of 15.80 to 16.00 mg. linoleic acid per 100 ml. of D.I. water.From the solubility data and conductivity values of linoleic acid the apparent classic and thermodynamic ionization constants were calculated to be 6.974±0.023×10−6 and 6.905±0.017×10−6 at 0.7°C. and 1.730±0.009×10−5 and 1.689±0.007×10−5 at 25°C., respectively.The result of the chemical interaction of linoleic acid and water is a saturated hydroxy fatty acid. This acid gave a positive test for glycol groups with periodic acid oxidation test and appeared to be a tetrahydroxy compound with the exact structure unknown.
Hexitol and sucrose esters of α‐sulfo fatty acids
Authors: Bistline R. G. , Smith F. D. , Well J. K. , Stirton A. J. 
Published: August 2007

AbstractUse of the α‐sulfo acid, the acid chloride and the methyl ester was explored in the preparation of mannitol, sorbitol and sucrose esters of α‐sulfopalmitic and α‐sulfostearic acids. The products were difficult to purify because of solubilization of reactants. The α‐sulfo esters are more soluble and more resistant to hydrolysis than hexitol and sucrose palmitates and stearates.
Nomographs for calculating the fatty acid composition of oils and fats from iodine and thiocyanogen values
Authors: Hussain S. A. , Dollear F. G. 
Published: August 2007

SummaryThe construction and use of nomographic charts for the calculation of the glyceride compositions of oils and fats have been described. Equations adopted by the American Oil Chemists' Society relating the glyceride composition with the iodine and thiocyanogen values of an oil were used for constructing the nomographs. The glyceride compositions of different oils calculated from the nomographs were found to agree reasonably well with those obtained by calculation from the equations.
Atorvastatin Decreases Triacylglycerol‐Associated Risk of Vascular Events in Coronary Heart Disease Patients
Authors: Athyros Vasilios G. , Kakafika Anna I. , Papageorgiou Athanasios A. , Tziomalos Konstantinos , Skaperdas Athanasios , Pagourelias Efstathios , Pirpasopoulou Athina , Karagiannis Asterios , Mikhailidis Dimitri P. ,   The GREACE Study Collaborative Group
Published: August 2007

AbstractHigh triacylglycerol (TAG) levels may predict vascular risk. The effect of a statin‐induced reduction in TAG levels, irrespective of HDL‐C increase, on clinical outcome has not yet been addressed by an endpoint study in patients with coronary heart disease (CHD). The GREACE study compared usual with structured care aimed at achieving LDL‐C = 100 mg/dL (2.6 mmol/L) by dose titration with atorvastatin. All patients had CHD and were followed for 3 years. This post hoc analysis of GREACE examines the effect of statins on TAG levels and their relation with cardiovascular disease (CVD) events in all patients and in the subgroup of patients with metabolic syndrome (MetS). Baseline TAG levels >150 mg/dL (1.7 mmol/L) were predictive of subsequent CVD events [cardiac mortality, non‐fatal myocardial infarction (MI), unstable angina (UA), revascularisation, congestive heart failure (CHF), and stroke] only in statin untreated patients. Stepwise regression analysis showed that with every 20% statin‐related TAG reduction there was a decrease in CVD risk by 12% (HR 0.88, 95% CI 0.75–0.95, P = 0.007) in the structured care group vs. the usual care group, by 8% (HR 0.92, 95% CI 0.81–0.97, P = 0.02) in all statin treated patients vs. the untreated ones and by 15% (HR 0.85, 95% CI 0.65–0.94, P = 0.005) in those with MetS treated with a statin vs. those untreated. Using the same analysis but only taking into consideration vascular events (cardiac mortality, non‐fatal MI, UA, revascularisation, and stroke) there was a 18% (HR = 0.82, 95% CI 0.57–0.96, P = 0.03) decrease in risk in the MetS (+) patients treated with a statin vs. those not on a statin, and a decrease in risk by 16% (HR = 0.84, 95% CI 0.53–1.07, P = 0.08), when only hard vascular endpoints (cardiac mortality, non‐fatal MI, and stroke) were considered. TAG levels are predictive of subsequent CVD events in statin untreated CHD patients. Statin (mainly atorvastatin)‐induced decrease in TAG levels was related to a significant reduction in subsequent CVD events. This benefit was more pronounced in CHD MetS (+) patients.
Column Fractionation of Canola Oil Deodorizer Distillate Using Supercritical Carbon Dioxide
Authors: Güçlü‐Üstündağ Özlem , Temelli Feral 
Published: August 2007

AbstractSemi‐continuous column fractionation of canola oil deodorizer distillate using supercritical CO2 (SCCO2) was carried out to determine the feasibility of value‐added processing of this feed material for the recovery of bioactive components such as sterols and tocopherols and to determine the effect of operating conditions [pressure (20, 25 MPa using a temperature gradient of 70–100 °C), temperature (70, 100 °C) and a linear temperature gradient (70–100 °C at 25 MPa)] on extract yield and separation efficiency. Total extract yield increased significantly (p ≤ 0.05) with pressure, whereas at isobaric conditions (25 MPa) the highest yield was obtained at the lowest temperature tested (70 °C). Fractionation efficiency was reflected in the composition of fractions and was affected by operating conditions. Residue composition was determined by extract yield in addition to selectivity. Use of the thermal gradient (70–100 °C) decreased the content of volatiles, free fatty acids and tocopherols while increasing sterol content significantly (p ≤ 0.05) to a level of 40% (GC area %) in the residue obtained at 25 MPa. The findings indicate the potential of canola oil deodorizer distillate as a source of sterols and warrant further research on the countercurrent column fractionation to improve the separation efficiency.
Excessive ventilation during early phase of exercise: A new predictor of poor long‐term outcome in patients with chronic heart failure
Authors: Jankowska Ewa A. , Witkowski Tomasz , Ponikowska Beata , Reczuch Krzysztof , Borodulin‐Nadzieja Ludmila , Anker Stefan D. , Piepoli Massimo F. , Banasiak Waldemar , Ponikowski Piotr 
Published: August 2007

AbstractBackground:Studies demonstrating prognostic value of excessive exercise ventilation in chronic heart failure (CHF) have focused on data derived from the whole cardiopulmonary exercise test (CPET). Whether ventilatory response to early phase of exercise is useful for risk stratification in CHF is unknown.Methods and results:We evaluated 216 patients with systolic CHF who underwent CPET (age: 60±11 years, NYHA class [I/II/III/IV]: 18/104/77/17). Ventilatory response to exercise (slope of regression line relating ventilation to carbon dioxide production) was calculated from the whole exercise test (VE‐VCO2‐all) and from the first 3min of exercise (early phase — VE‐VCO2‐3min). During follow‐up (mean: 40± 20months, >3years in survivors), 89 (41%) CHF patients died. High VE‐VCO2‐all and VE‐VCO2‐3min predicted poor outcome in single predictor analyses, and in multivariable models when adjusted for prognosticators (age, NYHA class, ejection fraction, peak VO2) (P<0.0001). In receiver operating characteristic curve analysis, areas under curve for 3‐year follow‐up were similar for VE‐VCO2‐all and VE‐VCO2‐3min. VE‐VCO2‐3min maintained its prognostic value in patients taking β‐blockers (P<0.0001) and those unable to perform maximal CPET (P=0.0009).Conclusions:In CHF patients, excessive ventilation assessed over the first 3min predicts poor outcome. Assessment of ventilatory response to exercise for prognostic stratification may be extended to patients unable to perform maximal CPET.
Dobutamine stress echocardiography and the effect of revascularization on outcome in diabetic and non‐diabetic patients with chronic ischaemic left ventricular dysfunction
Authors: Cortigiani Lauro , Sicari Rosa , Desideri Alessandro , Bigi Riccardo , Bovenzi Francesco , Picano Eugenio ,   on behalf of the VIDA (Viability Identification with Dobutamine Administration) Study Group
Published: August 2007

AbstractAim:To evaluate the interaction between prognostic effect of revascularization and viability in diabetic and non‐diabetic patients with ischaemic left ventricular dysfunction.Methods:612 patients with angiographically proven coronary artery disease and left ventricular ejection fraction <35% underwent dobutamine stress echocardiography to assess viability (peak‐rest wall motion score index >0.4). 262 patients (75 diabetics, 187 non‐diabetics) underwent revascularization and 350 (88 diabetics, 262 non‐diabetics) were on medical therapy.Results:During follow‐up 215 patients died. Independent predictors of mortality in revascularized patients were resting left ventricular ejection fraction (HR=0.93, 95% CI 0.89–0.97, p<0.0001), Δ WMSI>40 (HR=0.44, 95% CI 0.23–0.85, p=0.01), and age (HR=1.03, 95% CI 1.00–1.06, p=0.04). In medically treated patients, independent predictors of mortality were diabetes mellitus (HR=1.64, 95% CI 1.13–2.38, p=0.009), number of diseased vessels (HR=1.27, 95% CI 1.03–1.56, p=0.02), and age (HR–1.02, 95% CI 1.00=1.04, p–0.03). In revascularized patients, 4‐year mortality was 15% in those with viability and 26% in those without viability (p=0.04), there was no difference between diabetics and non‐diabetics (24% vs 22%; p=0.24).Conclusions:Viability at dobutamine stress echocardiography independently predicts improved outcome following revascularization in non‐diabetics as well as diabetic patients with ischaemic left ventricular dysfunction.
Chlorinated Diphenyl Ethers in Sediments, Biota, and the Water Column from Coastal British Columbia, Canada
Authors: Rayne Sierra , Michael Ikonomou , Garrett Chris 
Published: August 2007

AbstractPolychlorinated diphenyl ethers (PCDEs) are impurities in technical chlorophenol mixtures, are used as dielectric fluids in capacitors and as herbicides, antiseptics, food preservatives, and papers and textiles, and can be formed through the chlorination of organics in water and wastewater streams. Samples from semipermeable membrane devices (SPMDs), sediments, English sole, mussels, and Dungeness crab were collected from urban/industrial and remote sites along the marine coast of British Columbia and analyzed by congener-specific GC-MS analysis for mono- through deca-substituted PCDEs. Higher concentrations in biota and sediments were observed near urban/industrial areas, with evidence for food-chain biomagnification within major harbours. Correlations between size distributions and PCDE levels indicate these hydrophobic contaminants tend to preferentially partition into sediments with higher clay/silt fractions. Multivariate analysis of congener patterns shows distinct PCDE profiles among different species and environmental matrices, and evidence for favoured dechlorination pathways among the most commonly observed congeners in aquatic systems.