bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cohort study of patients with adrenal lesions discovered incidentally
Authors: Muth A , Hammarstedt L , Hellström M , Sigurjónsdóttir H Á , Almqvist E , Wängberg B 
Published: May 2011

AbstractBackgroundThis prospective cohort study investigated the incidence, clinical features and natural history of incidentally discovered adrenal mass lesions (adrenal incidentaloma, AI) in an unselected population undergoing radiological examination.MethodsDuring an 18-month period, all patients with AI were reported prospectively from all 19 radiology departments in western Sweden. Inclusion criteria were: incidentally discovered adrenal enlargement or mass lesion in patients without extra-adrenal malignancy on detection. Clinical and biochemical evaluation was performed on inclusion and after 24 months. Computed tomography (CT) of the adrenals was scheduled at 4, 12 and 24 months. Magnetic resonance imaging was performed for lesions larger than 20 mm. The indications for surgical excision were: hormone activity, lesion diameter more than 30 mm, lesion growth or other radiological features suspicious of malignancy.ResultsOf 534 patients assessed for eligibility, 226 (mean age 67 years, 62·4 per cent women; mean lesion diameter 23·9 mm, 22·6 per cent bilateral) fulfilled the inclusion criteria. Mean follow-up was 19·0 months. After baseline evaluation, 14 patients had surgery owing to primary hyperaldosteronism (3), catecholamine-producing tumour (1), tumour size (6), size and indication of subclinical hypercortisolism (3) and metastasis (1). No hypersecreting lesions were confirmed during follow-up; one patient underwent adrenalectomy for a suspected phaeochromocytoma (adrenocortical adenoma at histopathology). No primary adrenal malignancy was found.ConclusionIn this prospective cohort study 6·6 per cent of patients with an AI had surgery and benign hormone-producing tumours were verified in 3·1 per cent. Repeat CT and hormone evaluation after 2 years did not increase the sensitivity for diagnosis of malignant or hormone-producing tumours.
Late follow-up of a randomized trial of routine duplex imaging before varicose vein surgery
Authors: Blomgren L , Johansson G , Emanuelsson L , Dahlberg-Åkerman A , Thermaenius P , Bergqvist D 
Published: May 2011

Abstract

Background
Routine preoperative duplex examination led to an improvement in results 2 years after surgery for primary varicose veins. The aim of the present study was to evaluate the impact of preoperative duplex imaging after 7 years, in relation to other risk factors for varicose vein recurrence.

Methods
Patients with primary varicose veins were randomized to operation with (group 1), or without (group 2) preoperative duplex imaging. The same patients were invited to attend follow-up with interview, clinical examination and duplex imaging. Quality of life (QoL) was measured with the Short Form 36 questionnaire.

Results
Some 293 patients (343 legs) were included initially; after 7 years 227 were interviewed, or their records reviewed: 114 in group 1 and 113 in group 2. One hundred and ninety-four legs (95 in group 1 and 99 in group 2) were examined clinically and with duplex imaging. Incompetence was seen at the saphenofemoral junction and/or saphenopopliteal junction in 14 per cent of legs in group 1 and 46 per cent in group 2 (P &lt; 0·001). QoL was similar in both groups. After a mean follow-up of 7 years (and including patients who underwent surgery after the review), 15 legs in group 1 needed reoperation and 38 in group 2 (P = 0·001).

Conclusion
Routine preoperative duplex imaging improved the results of surgery for primary varicose veins for at least 7 years. Registration number: NCT01195623 (http://www.clinicaltrials.gov).
A rapid LC‐MS/MS method for quantitation of eszopiclone in human plasma: application to a human pharmacokinetic study
Authors: Hotha Kishore Kumar , Vijaya Bharathi D. , Jagadeesh B. , Ravindranath L. K. , Jaya Veera K. N. , Venkateswarulu V. 
Published: May 2011

ABSTRACTA highly reproducible, specific and cost‐effective LC‐MS/MS method was developed for simultaneous estimation of eszopiclone (ESZ) with 50 μL of human plasma using paroxetine as an internal standard (IS). The API‐4000 LC‐MS/MS was operated under the multiple reaction‐monitoring mode using the electrospray ionization technique. A simple liquid–liquid extraction process was used to extract ESZ and IS from human plasma. The total run time was 1.5 min and the elution of ESZ and IS occurred at 0.90 min; this was achieved with a mobile phase consisting of 0.1% formic acid–methanol (15:85, v/v) at a flow rate of 0.50 mL/min on a Discover C18 (50 × 4.6 mm, 5 µm) column. The developed method was validated in human plasma with a lower limit of quantitation of 0.1 ng/mL for ESZ. A linear response function was established for the range of concentrations 0.10–120 ng/mL (r > 0.998) for ESZ. The intra‐ and inter‐day precision values for ESZ were acceptable as per FDA guidelines. Eszopiclone was stable in the battery of stability studies, viz. bench‐top, autosampler and freeze–thaw cycles. The developed assay method was applied to an oral bioequivalence study in humans. Copyright © 2011 John Wiley & Sons, Ltd.
Estimation of thermodiffusion coefficients in ternary associating mixtures
Authors: Eslamian Morteza , Saghir M. Ziad 
Published: May 2011

AbstractFollowing the non‐equilibrium thermodynamics formulation and taking into account the complexities in the structure of aqueous associating mixtures, expressions are proposed to estimate the thermodiffusion coefficients in ternary associating mixtures, such as water and alcohol mixtures. The model expressions are used to estimate the thermodiffusion coefficients in methanol–ethanol–water, dimethyl sulfoxide (DMSO)–ethanol–water and DMSO–t‐butanol–water mixtures at various concentrations. The perturbed‐chain statistical associating fluid theory (PC‐SAFT) equation of state is used to obtain the mixture properties, such as the derivatives of the chemical potentials needed to evaluate the thermodiffusion coefficient expressions. The results show that at certain concentrations of one component, variation of the concentration of the other two components can cause a sign change in the thermodiffusion coefficients. While the model cannot be evaluated due to the lack of any pertinent experimental data, the model predictions may be used to choose suitable mixture compositions in space experiments to be performed onboard the International Space Station (ISS) in near future. © 2011 Canadian Society for Chemical Engineering
Natural Orbital Functional Theory and Reactivity Studies of Diradical Rearrangements: Ethylene Torsion as a Case Study
Authors: Lopez Xabier , Piris Mario , Matxain Jon M. , Ruipérez Fernando , Ugalde Jesus M. 
Published: May 2011

AbstractNatural orbital functional theory (NOFT) in its PNOF3 and PNOF4 implementations is used to investigate the potential energy surface (PES) of ethylene torsion. This rearrangement is taken as a case study to illustrate the satisfactory performance of the Piris Natural Orbital Functional (PNOF) toward rearrangements sensible to non‐dynamical electron correlation or near‐degeneracy effects. We show that the fulfillment of the G‐positivity condition, as implemented in PNOF4, is key to yield a correct description of structures with significant diradical character. We have found that PNOF4 yields an accurate description of these delicate PES and predicts the correct trends of the occupation numbers as compared with multiconfigurational wavefunction methods.
Selective Colorimetric Detection of Hg2+ and Mg2+ with Crown Ether Substituted N‐Aryl‐9‐aminobenzo[b]quinolizinium Derivatives
Authors: Tian Maoqun , Ihmels Heiko 
Published: May 2011

Abstract1,4‐Dioxa‐7,13‐dithia‐10‐azacyclopentadecane (AT215C5) or 1,4,7,10‐tetraoxa‐13‐azacyclopentadecane (A15C5) were attached as metal‐ion‐binding receptor units at the ortho or para positions of the 9‐amino‐N‐phenylbenzo[b]quinolizinium chromophore. The addition of Hg2+ or Mg2+ to the para isomers of the AT215C5–quinolizinium or A15C5–quinolizinium conjugate, respectively, led to a blueshift of the absorption maxima of each compound because of the reduced donor ability of the complexed amino group. In contrast, the addition of Hg2+ to a solution of the ortho‐AT215C5–quinolizinium conjugate in H2O/MeOH mixtures induced a significant redshift (ca. 50 nm) of the absorption maximum and enabled the photometric discrimination between Hg2+ and competing thiophilic cations, such as Ag+ or Pb2+, because the latter, as well as other competing metal ions, did not induce such an effect. It is proposed that the Hg2+‐induced redshift originates from the complexation of Hg2+ by the thiaazacrown ether followed by deprotonation of the secondary 9‐amino substituent of the aminobenzoquinolizinium unit. The resulting amide functionality increases the donor–acceptor interplay leading to the redshifted absorption and also coordinates to Hg2+ to form a lariat ether type complex. A similar effect was observed upon the addition of Mg2+ to the 9‐amino‐N‐phenylbenzo[b]quinolizinium derivative with the A15C5 unit in the ortho position; however, this effect was only operative in aprotic solvents, e.g. CH3CN, and with less than 1 mol‐equiv. of Mg2+.
A Novel Radical Cyclization Approach to Thieno‐Fused Heterocycles
Authors: Singh Prabal P. , Yadav Ashok K. , Ila Hiriyakkanavar , Junjappa Hiriyakkanavar 
Published: May 2011

AbstractAn efficient synthesis of novel aryl/heteroaryl‐substituted thieno‐fused heterocycles, that is, thieno[2,3‐b]thiophenes, thieno[2,3‐b]indoles, and pyrazolo[3,2‐c]thiophenes, involving radical‐mediated cyclization of 2‐(2‐bromoheteroaryl)‐3‐methylthio‐3‐aryl/heteroaryl acrylonitriles has been reported.
Bayesian Forecasting for Financial Risk Management, Pre and Post the Global Financial Crisis
Authors: Chen Cathy W.S. , Gerlach Richard , Lin Edward M. H. , Lee W. C. W. 
Published: May 2011

ABSTRACTValue‐at‐risk (VaR) forecasting via a computational Bayesian framework is considered. A range of parametric models is compared, including standard, threshold nonlinear and Markov switching generalized autoregressive conditional heteroskedasticity (GARCH) specifications, plus standard and nonlinear stochastic volatility models, most considering four error probability distributions: Gaussian, Student‐t, skewed‐tand generalized error distribution. Adaptive Markov chain Monte Carlo methods are employed in estimation and forecasting. A portfolio of four Asia–Pacific stock markets is considered. Two forecasting periods are evaluated in light of the recent global financial crisis. Results reveal that: (i) GARCH models outperformed stochastic volatility models in almost all cases; (ii) asymmetric volatility models were clearly favoured pre crisis, while at the 1% level during and post crisis, for a 1‐day horizon, models with skewed‐terrors ranked best, while integrated GARCH models were favoured at the 5% level; (iii) all models forecast VaR less accurately and anti‐conservatively post crisis. Copyright © 2011 John Wiley & Sons, Ltd.
Synthesis and insecticidal activities of novel spin‐labeled derivatives of camptothecin
Authors: Liu Ying‐Qian , Dai Wei , Tian Jing , Yang Liu , Feng Gang , Zhou Xing‐Wen , Kou Liang , Zhao Yong‐Long , Li Wen‐Qun , Li Lin‐Hai , Li Hong‐Yu 
Published: May 2011

AbstractContinuing our search for natural product based compounds for the control of Brontispa longissima larvae, eight spin‐labeled camptothecin derivatives 7a–h and the intermediate 2 were first tested for their insecticidal activities against fifth‐instar larvae of Brontispa longissima. Among all the tested compounds, especially compounds 7a and 2 showed promising insecticidal activities with the corrected mortality rates of 69.55% and 74.07% against fifth‐instar larvae of B. longissima, respectively. The different insecticidal activity ranges of these compounds indicated that the variation of the structures of l‐amino acids in these compounds markedly affected the activity profiles of this compound class, and some important SAR information has been revealed from it. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 22:687–691, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.20734
Wealth distribution in Chinese bankruptcy reorganization law and practice
Authors: Ren Yongqing 
Published: May 2011

AbstractWealth distribution provisions in bankruptcy reorganization law, which regulate the distribution of the debtor's overall value among all the interested parties with an aim of ensuring a fair and equitable distribution, constitute an important part of the bankruptcy reorganization law. This article first examines the wealth distribution provisions contained in Chinese bankruptcy reorganization law from a Sino‐US perspective and then explores the wealth distribution in Chinese bankruptcy reorganization practice through an empirical study of 18 bankruptcy reorganization cases of listed corporations in China. After an analysis of Chinese legal provisions on wealth distribution and their application in practice, this article draws the conclusion that wealth distribution in Chinese bankruptcy reorganization practice is far from being fair and equitable, which may cause abused use of the reorganization proceeding and distort the operation of the bargaining mechanism. Reform suggestions for Chinese bankruptcy reorganization law are proposed at the end. Copyright © 2011 John Wiley & Sons, Ltd.
Covalent and ionic co‐cross‐linking—An original way to prepare chitosan–gelatin hydrogels for biomedical applications
Authors: Jătariu (Cadinoiu) Anca N. , Popa Marcel , Curteanu Silvia , Peptu Cătălina A. 
Published: May 2011

AbstractThe first goal of this work was to develop a method for obtaining interpenetrating gelatin (G)–chitosan (CS) networks prepared by double cross‐linking (covalent followed by ionic) that exhibit hydrogel character. The second goal was to modulate their properties as a function of the preparation parameters by using neural network models. This study was therefore carried out by experiment and simulation. The covalent cross‐linking resulted from the reaction between the carbonyl groups of glutaraldehyde with amino groups belonging to both polymers; the ionic cross‐linking is based on the interaction between tripolyphosphate anions and protonated amine groups (ammonium ions) of the polymers. The total cross‐linking density (indirectly assessed by estimating the water swelling capacity) and the ability to include hydrosoluble bioactive principles are influenced by the following process parameters: the CS/G ratio, the amount of ionic cross‐linker, and the ionic cross‐linking time. The prepared hydrogels were characterized with respect to their structural, morphological, and some physical properties. The hydrogels ability to load high amounts of water‐soluble drugs indicates their potential use as carriers for biologically active principles in the human body. A neural network methodology was applied to model the swelling degree and caffeine loading/release capacity depending on reaction conditions; in addition, applying this method, the optimal preparation conditions have been determined, targeting pre‐established values for swelling degree or maximum caffeine value. The accuracy of the results obtained through this technique proves that the neural networks are suitable tools for modeling cross‐linking processes taking place complex nonlinear polymers. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 2011.
Separation and purification of scandium by solvent extraction and related technologies: a review
Authors: Wang Weiwei , Cheng Chu Yong 
Published: May 2011

AbstractThe technologies of solvent extraction, ion exchange, and liquid membrane for the separation and purification of scandium are reviewed. Acidic and neutral organo‐phosphorus extractants are most widely used in practice, with high extraction efficiencies. Their disadvantages originate from the high stripping acidity required for the former and the poor selectivity for the latter. Carboxylic acids, amines, and acidic β‐diketone have also been widely used to extract scandium from solutions with low acidities. Mixed extractants or synergistic systems for the solvent extraction of scandium have been developed. Extraction efficiencies are influenced by extraction conditions such as aqueous matrixes and acidities, types of diluents and A/O ratios. Scandium(III) extractions are interfered with by commonly associated elements such as iron(III), zirconium(IV), titanium(IV), thorium(IV), yttrium(III) and lanthanides(III). The advantages and disadvantages of applications of ion exchange and liquid membrane technologies for scandium recovery are reviewed and compared with solvent extraction. Copyright © 2011 Society of Chemical Industry
Synthesis and antimicrobial activity of some heterocyclic 2,6‐bis(substituted)‐1,3,4‐thiadiazolo‐, oxadiazolo‐, and oxathiazolidino‐pyridine derivatives from 2,6‐pyridine dicarboxylic acid dihydrazide
Authors: Ghozlan Said A. S. , Al‐Omar Mohammed A. , Amr Abd El‐Galil E. , Ali Korany A. , El‐Wahab Ahmed A. Abd 
Published: May 2011

AbstractIn this work, we report on the synthesis and preliminary biological activity screening of several heterocyclic derivatives 2, 3, 4, 5, 6, 7, 8, 9, 10, 10a, 10b, 11, 11a, 11b, 12, 12a, 12b, 13, 13a, 13b, 14, 15 based on N2′,N6′‐diphenylthiosemi‐carbazide pyridine‐2,6‐dicarbohydrazide 2, which has been obtained from the corresponding dihydrazide 1. The biological screening showed that many of these compounds have good antimicrobial activities. The structure of the new compounds has been established on the bases of chemical and spectroscopic evidences. J. Heterocyclic Chem., (2011).
Synthesis of 4‐(1‐phenyl‐1H‐pyrazol‐3‐yl)‐[1,2,4]triazolo[4,3‐a]quinoxalines and their 4‐halogenopyrazolyl analogs
Authors: Atta Kamal F. M. , El Ashry El Sayed H. 
Published: May 2011

AbstractSynthesis of {3‐[1‐(ethoxycarbonyl)‐[1,2,4]triazolo[4,3‐a]quinoxalin‐4‐yl]‐1‐phenyl‐1H‐pyrazol‐5‐yl}methyl ethyl oxalate (2), ethyl 4‐[5‐(acetoxymethyl)‐1‐phenyl‐1H‐pyrazol‐3‐yl]‐[1,2,4]triazolo[4,3‐a]quioxaline‐1‐carboxylate (4), [4‐halo‐1‐phenyl‐3‐(1‐phenyl‐[1,2,4]triazolo[4,3‐a]quioxalin‐4‐yl)‐1H‐pyrazol‐5‐yl]methyl acetate (11), {4‐halo‐3‐[1‐methyl‐[1,2,4]triazolo[4,3‐a]quinoxalin‐4‐yl]‐1‐phenyl‐1H‐pyraz‐ol‐5‐yl}methyl acetate (13), and [3‐([1,2,4]triazolo‐[4,3‐a]quinoxalin‐4‐yl)‐4‐halo‐1‐phenyl‐1H‐pyrazol‐5‐yl] methyl formate (15) was accomplished. The structural investigation of the new compounds is based on chemical and spectroscopic evidences. J. Heterocyclic Chem., (2011)
Functional implications of variation in pectoral fin ray morphology between fishes with different patterns of pectoral fin use
Authors: Taft Natalia K. 
Published: May 2011

AbstractIn this study, I compare the morphology from the pectoral fin rays from the benthic longhorn sculpin (Myoxocephalus octodecimspinosus) to those from a species that does not use its fins for substrate contact, the yellow perch (Perca flavescens). I use CT scanning technology to compare the shape and structure of the paired hemitrichia that make up the pectoral fin rays between these species. I found that the structure of hemitrichia of the fin rays in yellow perch is consistent with previous descriptions for pelagic fishes. They are almost completely segmented, have a crescent shape in cross section, and are branched distally. In contrast, longhorn sculpin hemitrichia exhibit morphological regionalization along the proximo‐distal length of the ray. The most proximal 20–50% of the length of the hemitrichia is unsegmented and cylindrical in cross section. Distally, the fin rays of longhorn sculpin are segmented and crescent‐shaped but do not branch. I measured the second moment of area of the hemitrichia at distances of 10%, 30%, 50%, and 70% distance along the length of the fin rays. The cylindrical regions of the sculpin hemitrichia had a higher second moment of area than the crescent‐shaped regions in either species. I hypothesize that that this regionalization of individual fin rays provides resistance to bending proximally and flexibility distally, features that may be useful during substrate contact. This combination of an elongate, unsegmented proximal region and segmented distal region in fin rays has not yet been described among extant ray‐finned fishes. However, this structure is reminiscent of that of the elongate cylindrical region found in the fossil sarcopterygian fish Eusthenopteron. J. Morphol. 2011. © 2011 Wiley‐Liss, Inc.
Energy at work: A measurement validation and linkage to unit effectiveness
Authors: Cole Michael S. , Bruch Heike , Vogel Bernd 
Published: May 2011

SummaryWe introduce the notion that the energy of individuals can manifest as a higher‐level, collective construct. To this end, we conducted four independent studies to investigate the viability and importance of the collective energy construct as assessed by a new survey instrument—the productive energy measure (PEM). Study 1 (n = 2208) included exploratory and confirmatory factor analyses to explore the underlying factor structure of PEM. Study 2 (n = 660) cross‐validated the same factor structure in an independent sample. In study 3, we administered the PEM to more than 5000 employees from 145 departments located in five countries. Results from measurement invariance, statistical aggregation, convergent, and discriminant‐validity assessments offered additional support for the construct validity of PEM. In terms of predictive and incremental validity, the PEM was positively associated with three collective attitudes—units' commitment to goals, the organization, and overall satisfaction. In study 4, we explored the relationship between the productive energy of firms and their overall performance. Using data from 92 firms (n = 5939employees), we found a positive relationship between the PEM (aggregated to the firm level) and the performance of those firms. Copyright © 2011 John Wiley & Sons, Ltd.
Ultrasonic nebulization extraction coupled with headspace hollow fiber microextraction of pesticides from root of Panax ginseng C.A. Mey.
Authors: Li Xueyuan , Wang Lu , Wang Ziming , Zhang Huihui , Su Rui , Xu Xu , Zhang Hanqi 
Published: May 2011

AbstractThe ultrasonic nebulization extraction coupled with headspace hollow fiber microextraction (UNE‐HS‐HFME) was applied for the extraction of pesticides from root of Panax ginseng C.A. Mey. Experimental parameters, which affect the performances of ultrasonic nebulization extraction coupled with headspace hollow fiber microextraction, such as the kind of acceptor solvent in the pore of the fiber wall, the sample amount, extraction time, salt concentration in extraction solvent, pH of the acceptor solution, the elution time, and times were studied and optimized. The analytes were determined by high‐performance liquid chromatography. The detection limits for simeton, monolinuron, chlortoluron, karmex, and prebane are 20.9, 18.4, 18.2, 12.4, and 22.2 μg/kg, respectively. Besides volatile and semi‐volatile compounds, the non‐volatile compounds also can be determined by the proposed method. The extraction and enrichment process can be performed simultaneously.