bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mixture design in the optimization of a microemulsion system for the electrokinetic chromatographic determination of ketorolac and its impurities: Method development and validation
Authors: Furlanetto Sandra , Orlandini Serena , Marras Anna Maria , Mura Paola , Pinzauti Sergio 
Published: February 2006

AbstractMicroemulsion EKC (MEEKC) was used for the determination of ketorolac and its three impurities. The microemulsion system was optimized, for the first time in the literature, using a multivariate strategy involving a mixture design. A 13‐run experimental plan covering an experimental domain defined by the components aqueous phase (10 mM borate buffer pH 9.2), oil phase (n‐heptane) and surfactant/cosurfactant (SDS/n‐butanol) was carried out. Good results were obtained with all microemulsions tested considering as responses analysis time and resolution, and according to the desirability function the best microemulsion system was constituted by 90.0% 10 mM borate buffer, 2.0% n‐heptane, 8.0% of SDS/n‐butanol in 1:2 ratio. Finally, with the aim of reducing analysis time, a response surface study was carried out in the experimental domain defined by the process variables temperature and voltage and the best values were 17°C and −17 kV, respectively. Applying the optimised conditions, a complete resolution among the analytes was obtained in about 3 min using the short‐end injection method. The method was validated for both drug substances and drug product and was applied to the quality control of ketorolac in coated tablets. A comparison of MEEKC, MEKC and CEC for assaying ketorolac and its related substances has been made.
Chiral microemulsion electrokinetic chromatography with two chiral components: Improved separations via synergies between a chiral surfactant and a chiral cosurfactant
Authors: Kahle Kimberly A. , Foley Joe P. 
Published: February 2006

AbstractIn this study, the combination of two chiral components in a microemulsion formulation for the separation of enantiomers via microemulsion EKC (MEEKC) was successfully accomplished. Previous publications of chiral microemulsions have utilized only one chiral entity; the surfactant, cosurfactant, or oil was chiral. This is the first study, to date, of the effects of using two chiral species in a single pseudostationary phase (PSP). The chiral surfactant dodecoxycarbonylvaline (DDCV) was used in conjunction with the chiral cosurfactant S‐2‐hexanol. Ethyl acetate was incorporated as the oil core of the microemulsion and the buffer was 50 mM phosphate at a pH of 7. Additionally, a microemulsion prepared with racemic 2‐hexanol was used for comparison to a previous DDCV microemulsion and as a baseline for the newly formulated dual chiral microemulsion. The efficiencies, resolutions, and enantioselectivities for the S‐2‐hexanol, racemic 2‐hexanol, and original 1‐butanol DDCV microemulsions are compared. The hexanol‐based PSPs provide improved efficiencies and resolutions. To evaluate the combination of each DDCV enantiomer (R and S) with S‐2‐hexanol, changes in Gibb's free energy were calculated. A synergistic effect was found when two chiral components were combined to form a microemulsion.
Assessment of gully erosion rates through interviews and measurements: a case study from northern Ethiopia
Authors: Nyssen Jan , Poesen Jean , Veyret‐Picot Maude , Moeyersons Jan , Haile Mitiku , Deckers Jozef , Dewit Joke , Naudts Jozef , Teka Kassa , Govers Gerard 
Published: February 2006

AbstractGullying has been widespread in the Ethiopian Highlands during the 20th century. It threatens the soil resource, lowers crop yields in intergully areas through enhanced drainage and desiccation, and aggravates flooding and reservoir siltation. Knowing the age and rates of gully development during the last few decades will help explain the reasons for current land degradation.In the absence of historical written or photographic documentation, the AGERTIM method (Assessment of Gully Erosion Rates Through Interviews and Measurements) has been developed. It comprises measurements of contemporary gully volumes, monitoring of gully evolution over several years and semi‐structured interview techniques. Gully erosion rates in the Dogu'a Tembien District, Tigray, Ethiopia, were estimated in three representative case‐study areas.In Dingilet, gullying started around 1965 after gradual environmental changes (removal of vegetation from cropland in the catchment and eucalyptus plantation in the valley bottom); rill‐like incisions grew into a gully, which increased rapidly in the drier period between 1977 and 1990. The estimated evolution of the total gully volume in the other areas show patterns similar to those of the Dingilet gully. Average gully erosion rate over the last 50 years is 6·2 t ha−1 a−1. Since 1995, no new gullies have developed in the study area. Area‐specific short‐term gully erosion rates are now on average 1·1 t ha−1 a−1.The successful application of the AGERTIM method requires an understanding of the geomorphology of the study area and an integration of the researchers with the rural society. It reveals that rapid gully development in the study area is some 50 years old and is mainly caused by human‐induced environmental degradation. Under the present‐day conditions of ‘normal’ rain and catchment‐wide soil and water conservation, gully erosion rates are decreasing. Copyright © 2006 John Wiley & Sons, Ltd.
Anti‐obesity effects of green tea: From bedside to bench
Authors: Wolfram Swen , Wang Ying , Thielecke Frank 
Published: February 2006

AbstractDuring the last decade, the traditional notion that green tea consumption benefits health has received significant scientific attention and, particularly, the areas of cardiovascular disease and cancer were subject to numerous studies. Due to the ever‐growing obesity pandemic, the anti‐obesity effects of green tea are being increasingly investigated in cell, animal, and human studies. Green tea, green tea catechins, and epigallocatechin gallate (EGCG) have been demonstrated in cell culture and animal models of obesity to reduce adipocyte differentiation and proliferation, lipogenesis, fat mass, body weight, fat absorption, plasma levels of triglycerides, free fatty acids, cholesterol, glucose, insulin and leptin, as well as to increase beta‐oxidation and thermogenesis. Adipose tissue, liver, intestine, and skeletal muscle are target organs of green tea, mediating its anti‐obesity effects. Studies conducted with human subjects report reduced body weight and body fat, as well as increased fat oxidation and thermogenesis and thereby confirm findings in cell culture systems and animal models of obesity. There is still a need for well‐designed and controlled clinical studies to validate the existing and encouraging human studies. Since EGCG is regarded as the most active component of green tea, its specific effects on obesity should also be investigated in human trials.
Characteristics of Perianal Abscess and Fistula‐in‐Ano in Healthy Children
Authors: Serour Francis , Gorenstein Arkadi 
Published: February 2006

AbstractBackgroundProbably because of the low frequency, perianal abscess (PA) and fistula‐in‐ano (FIA) in children older than 2 years have not been investigated except in those with a predisposing condition such as Crohn’s disease. This study aims to summarize our experience about the characteristics and treatment of PA and FIA in healthy children.MethodsThe charts of all children older than 24 months of age treated for PA and/or FIA from 1990 to 2003 were reviewed.ResultsWe found 40 patients, 37 of them boys (92.5%), ranging from 2 to 14 years of age (average: 7.19 years). At the first examination, the diagnosis was PA in 36 patients (mean age: 6.8 years; range: 2.3–13 years), and FIA in 4 patients (mean age: 10.8 years; range: 6–14 years). The primary local treatment of PA was drainage (needle aspiration in 26 patients, and incision and drainage in 4 patients) and local care in 6 patients. All patients received antibiotics. Overall, 29 children (80.6%) had primary cure of the abscess. Evolution included recurrent abscess in 3 patients (8.3%) and FIA in 4 patients (11.1%). Crohn’s disease was diagnosed in only one boy with an abscess of long duration. No patient developed a new PA in another location or a recurrent FIA. Four male patients aged 6 to 14 years (range: 7.1 years) had a FIA of long duration. One patient underwent a fistulectomy. Crohn’s disease was found in three other children and treated conservatively.ConclusionDrainage of PA by needle aspiration associated with antibiotics is effective in children older than 2 years of age with a low rate of evolution toward FIA. Associated pathology must be ruled out in children with FIA.
1H NMR and spectrophotometric study of alkaline metal ion complexes with N-dansyl aza-18-crown-6
Authors: Ossowski Tadeusz , Sulowska Hanna , Karbowiak Tomasz , Zarzeczanska Dorota , Gierczyk Błażej , Schroeder Grzegorz 
Published: February 2006

AbstractFormation of complexes of A18C6-Dns and metal cations (Ca2+, Sr2+, Ba2+ and Mg2+) in acetonitrile has been studied by NMR, absorption and fluorescence spectroscopy and PM5 semi-empirical methods. A18C6-Dns forms stable complexes with Ca2+, Sr2+ and Ba2+ cations. The stability constants of various complexes are determined by different methods and their structures are visualised by the PM5 semi-empirical calculations.
Protonation acidity constants for benzotoluidides in sulfuric acid solutions
Authors: Stojković Goran , Anastasova Frosa 
Published: February 2006

AbstractThe protonation of o-, m-and p-benzotoluidide in sulfuric acid solutions is studied by UV spectroscopy in the 190–350 nm region. Principal component analysis is applied to estimate the contributions of the effect of protonation and the medium effect. For the substances studied in this work, the first principal component (PC) captures about 98 % of the variance and the second PC ∼100 % of the cumulative percentage variance in the 210–350 nm region. The same spectral region is used for calculation of the ionization ratio from the coefficients of the first PC and mole fractions of the base and its conjugate acid. Using these data and Hammett's equation (pK BH + = H X + log I), the pK BH + values for the protonation reaction are obtained. The dissociation constants as well as the solvent parameters m* (∼0.43) and ϕ (∼0.60) are calculated using the Excess Acidity Method (-pK BH += 2.28–2.30) and the Bunnett-Olsen Method (-pK BH += 2.24–2.28). The probable sites of protonation are discussed.
An advanced multivariate statistical approach to study coastal sediment data
Authors: Simeonova Pavlina , Sarbu Costel , Spanos Thomas , Simeonov Vasil , Tsakovski Stefan 
Published: February 2006

AbstractThe present paper deals with the application of classical and fuzzy principal components analysis to a large data set from coastal sediment analysis. Altogether 126 sampling sites from the Atlantic Coast of the USA are considered and at each site 16 chemical parameters are measured. It is found that four latent factors are responsible for the data structure (“natural”, “anthropogenic”, “bioorganic”, and “organic anthropogenic”). Additionally, estimating the scatter plots for factor scores revealed the similarity between the sampling sites. Geographical and urban factors are found to contribute to the sediment chemical composition. It is shown that the use of fuzzy PCA helps for better data interpretation especially in case of outliers.
Silica hybrid nanocomposites
Authors: Chernev Georgi , Samuneva Bisserka , Djambaski Petar , Salvado Isabel , Fernandes Helena 
Published: February 2006

AbstractIn this work we present experimental results about the formation, properties and structure of sol — gel silica based biocomposite containing Calcium alginate as an organic compound. Two different types of silicon precursors have been used in the synthesis: tetramethylortosilicate (TMOS) and ethyltrimethoxysilane (ETMS). The samples have been prepared at room temperature. The hybrids have been synthesized by replacing different quantitis of the inorganic precursor with alginate. The structure of the obtained hybrid materials has been studied by XRD, IR Spectroscopy, EDS, BET and AFM. The results proved that all samples are amorphous possessing a surface area from 70 to 290 m2/g. It has also been established by FT IR spectra that the hybrids containing TMOS display Van der Walls and Hydrogen bonding or electrostatic interactions between the organic and inorganic components. Strong chemical bonds between the inorganic and organic components in the samples with ETMS are present. A self-organized nanostructure has been observed by AFM. In the obtained hybrids the nanobuilding blocks average in size at about 8–14 nm for the particles.
Solid state linear-dichroic infrared (IR-LD) spectroscopic characterization of α-and β-glycine polymorphs
Authors: Ivanova Bojidarka 
Published: February 2006

AbstractIR-LD spectroscopic analysis using nematic liquid crystal suspension as a solid-state orientation technique and the reducing-difference procedure for polarized spectra interpretation are applied to the α-and β-polymorphs of glycine. Both structural analysis and detailed IR band assignments were carried out.
Category with a natural cone
Authors: Díaz Francisco , Rodríguez-Machín Sergio 
Published: February 2006

Abstract
Generally, in homotopy theory a cylinder object (or, its dual, a path object) is used to define homotopy between morphisms, and a cone object is used to build exact sequences of homotopy groups. Here, an axiomatic theory based on a cone functor is given. Suspension objects are associated to based objects and cofibrations, obtaining homotopy groups referred to an object and relative to a cofibration, respectively. Exact sequences of these groups are built. Algebraic and particular examples are given. We point out that the main results of this paper were already stated in [3], and the purpose of this article is to give full details of the foregoing.
On solutions of third order nonlinear differential equations
Authors: Mojsej Ivan , Ohriska Ján 
Published: February 2006

Abstract
The aim of our paper is to study oscillatory and asymptotic properties of solutions of nonlinear differential equations of the third order with deviating argument. In particular, we prove a comparison theorem for properties A and B as well as a comparison result on property A between nonlinear equations with and without deviating arguments. Our assumptions on nonlinearity f are related to its behavior only in a neighbourhood of zero and/or of infinity.
On differences of two squares
Authors: Kühleitner Manfred , Nowak Werner 
Published: February 2006

Abstract
The arithmetic function ρ(n) counts the number of ways to write a positive integer n as a difference of two squares. Its average size is described by the Dirichlet summatory function Σn≤x

ρ(n), and in particular by the error term R(x) in the corresponding asymptotics. This article provides a sharp lower bound as well as two mean-square results for R(x), which illustrates the close connection between ρ(n) and the number-of-divisors function d(n).
Teenage parenthood among child welfare clients: A Swedish national cohort study of prevalence and odds
Authors: Vinnerljung Bo , Franzén Eva , Danielsson Maria 
Published: February 2006

AbstractTo assess prevalence and odds for teenage parenthood among former child welfare clients, we used national register data for all children born in Sweden 1972–1983 (), including 49,582 former child welfare clients with varying intervention experiences. Logistic regression models, adjusted for demographic, socio‐economic and familial background factors, were used to estimate odds ratios.Among youth who received interventions in adolescence, 16–19% of the girls and 5–6% of the boys became teenage parents, compared to 3% for girls and 0.7% for boys without child welfare experiences. Youths who entered child welfare services in their teens had four‐ to fivefold adjusted odds for becoming a teenage parent. For other child welfare clients, adjusted odds were mostly twofold.Youth of both sexes who receive child welfare services in adolescence are a high‐risk group for teenage parenthood. Child welfare agencies should, as a minimum, provide each individual client youth with access to birth control counselling and contraceptives.
Beyond parenting practices: Extended kinship support and the academic adjustment of African‐American and European‐American teens
Authors: Pallock Linda L. , Lamborn Susie D. 
Published: February 2006

ABSTRACTThis study examined adolescents’ perceptions of parenting practices and extended kinship support in relation to academic adjustment for 104 African American and 60 European American 9th and 10th graders (14 and 15 year olds). For African‐American teens, parental acceptance was associated with school values, teacher bonding, and work orientation. Higher levels of behavioral control and lower levels of psychological control were associated with a stronger work orientation. After accounting for the demographic variables and the three parenting practices, higher levels of extended kinship support related to stronger school values, higher teacher bonding, and a stronger work orientation. For European‐American teens, parental acceptance related to academic adjustment, including stronger school values, higher teacher bonding, and a stronger work orientation. European‐American adolescents with stronger extended kinship networks reported higher teacher bonding and a stronger work orientation. Results indicate the importance of extended kinship support for both African‐American and European‐American adolescents.
Comparison of performance of two size groups of farmed cod (Gadus morhua L.) juveniles following transfer to sea cages
Authors: Watson J.T. , Sales S. , Cumming G. , Fitzsimmons S.D. , Walden J. , Arthur G. , Saravanan S. , McEvoy L.A. 
Published: February 2006

AbstractIn order to investigate the biologically and economically optimum size for sea transfer of cultured cod, replicated trials were undertaken using experimental cages (1.5 m × 1 m × 1 m) stocked with two size grades of cod juveniles previously “untested” for on-growing at sea in Shetland: “small grade” (SG), 9.3-g mean weight (±2.08 s.d.) and “large grade” (LG), 19.4-g mean weight (±4.48 s.d.). Survival was high in both grades tested, with no significant difference in overall mortality (7.3% (SG) and 8.4% (LG)). A significant difference was observed in the overall percentage growth per day (%SGR) (p = 0.02), with SG and LG exhibiting values of 1.3 and 1.08, respectively. Regression analysis of body weight gain over time between the two grades revealed a significantly higher proportional weight gain in SG (p = 0.01). Cost analysis revealed an initial saving of 8.5% by selecting SG juveniles. This saving was reduced to 2.9% when the cost of feeding these fish was taken into account. However, food wastage was higher in this study than would be expected in a commercial operation, suggesting that the actual saving for the on-grower could be greater than 2.9%. Selecting smaller sized juveniles for transfer will increase the growout period. However, this may be offset by the fact they may be transferred earlier, at a significantly lower price.
Growth, behaviour, and digestive enzyme activity in larval Atlantic cod (Gadus morhua) in relation to rotifer lipid
Authors: O'Brien-MacDonald Kelly , Brown Joseph A. , Parrish Christopher C. 
Published: February 2006

AbstractAtlantic cod (Gadus morhua) show great potential for aquaculture, but much is unknown about their digestive capacity and efficiency. An integrated experiment was performed on cod larvae to investigate the variability in digestive development in response to the quantity of lipid in the rotifer enrichment. Survival, growth, behaviour, and digestive enzyme data from hatching to metamorphosis [0–450 dd (degree-days)] were measured. Four treatments were used in triplicate: high lipid rotifer enrichment (HLRE), low lipid rotifer enrichment (LLRE), green water, and unfed. Swimming activity and attacks (captures + misses) on prey were higher in the HLRE group at 100 dd than in other treatments, and this difference increased thereafter. There was no difference in digestive enzyme activity between the unfed and greened treatments, while the LLRE larvae had lower activity levels than larvae fed HLRE by 100–150 dd for all enzymes assayed. The larvae in the unfed and green water treatments did not survive past 100 dd. All the LLRE cod had died by 250 dd. Results suggest that a higher quantity of lipid in the rotifer enrichment will not only promote better growth and survival in Atlantic cod larvae but appears to provide more energy, allowing larvae to capture more live prey.
Partial Laser Arytenoidectomy in the Management of Bilateral Vocal Fold Immobility: A Modification Based on Functional Anatomical Study of the Cricoarytenoid Joint
Authors: Al‐Fattah Hesham Abd , Hamza Ashraf , Gaafar Alaa , Tantawy Ahmed 
Published: February 2006

OBJECTIVETo establish the anatomical relationships between the arytenoid and cricoid cartilages and apply these findings to design an arytenoidectomy based on a sound anatomical basis.STUDY DESIGNIn 50 patients the length of the vocal process and the distance between vocal process tip and upper border of the cricoid cartilage were endoscopically measured. Twenty‐five total laryngectomy specimens were sagittally and axially sectioned to verify the position of the arytenoids and their relation to the cricoid. The anatomical findings led to the design of laser partial arytenoidectomy and cordotomy (L‐PAC), which was used in 45 patients with bilateral cord paralysis in adduction.RESULTSThe anatomical findings showed that the cricoarytenoid joint did not contribute to the airway in any of the measured specimens. Using L‐PAC, 100% of the patients were decannulated and no patient needed a postoperative tracheostomy at any time. Only 3 patients experienced minimal postoperative aspiration to liquids (6.7%). Reasonable phonation was achieved as regarded by a speech analysis battery. Three patients (6.7%) needed a contralateral L‐PAC.CONCLUSIONSThe shape of the cricoid and the location of its axis of maximum width ought to dictate the technique of glottic widening to be used in bilateral cord immobility in adduction. The present extra‐articular technique, L‐PAC, showed its versatility in providing an effective balance between the protective, the respiratory, and to lesser extent the phoniatory functions.EBM rating: C‐4
Radial Forearm Free Flap Donor Site Outcomes Comparison by Closure Methods
Authors: Ho Tang , Couch Marion , Carson Kathryn , Schimberg Amy , Manley Karen , Byrne Patrick J. 
Published: February 2006

OBJECTIVETo compare the functional and aesthetic outcomes of radial forearm free flap (RFFF) donor sites reconstructed with full‐thickness skin graft (FTSG), split thickness skin graft (STSG) alone, and STSG overlying an acellular dermal matrix (AlloDerm).STUDY DESIGN AND SETTINGA cross‐sectional cohort study at a tertiary care hospital.RESULTSTwenty‐five head and neck cancer patients who underwent reconstruction with RFFF completed the evaluations (STSG = 10, FTSG = 8, STSG with AlloDerm = 7). Subjective evaluations of postoperative function by questionnaires showed no significant differences among the 3 groups (P = 0.93). In blinded evaluations by surgeons, the STSG group obtained the highest aesthetic outcome score (3.39 of 5.0), followed by FTSG (2.89) and STSG with AlloDerm (2.80). However, the difference was not statistically significant (P = 0.32). Objective measurements of postoperative function by certified occupational therapists were comparable among the 3 groups with the exception of a mildly decreased range of wrist flexion (P = 0.036) and ulnar deviation (P = 0.016) in the FTSG group.CONCLUSIONSThe 3 methods of reconstruction have comparable postoperative functional and aesthetic outcomes.SIGNIFICANCEEach of the 3 methods of reconstruction has low morbidity and satisfactory aesthetic and functional outcomes.EBM rating: B‐2b