bluuebunny/crossref_metadata_2025_split huggingface dataset:
Seasonal Variations of Lipid Content and Composition in Perna viridis
Authors: Li Duo , Zhang Yonghua , Sinclair Andrew J. 
Published: June 2007

AbstractThe total lipid content, composition of main lipid classes, composition of sterols and composition of fatty acids in the main glycerolipids of Perna viridis were analyzed through four seasons using TLC‐FID and GLC. Mussel samples were collected during different seasons between 2003 and 2004 from Shengsi Island, Zhejiang Province, China and stored frozen prior to freeze‐drying and lipid extraction. Ten grams of dried mussel powder of each season were analyzed. Total lipid content ranged from 14.5 g/100 g in spring month to 7.8 g/100 g dried mussel powder in autumn month. The predominant lipid in spring month was triacylglycerol (TAG), however, in the other three seasons the phospholipids (PL) was the main lipid class. The most abundant fatty acid in TAG, PL and phosphatidylcholine (PC) was 16:0, with the summer samples having the highest proportion (24–30% of total fatty acid) and winter the lowest (14–22%). In phosphatidylethanolamine (PE), the spring samples had the highest proportions of 16:0. The predominant polyunsaturated fatty acids (PUFA) were 22:6n‐3 and 20:5n‐3 in TAG, PL, PE and PC (25–40%). The proportions of 22:6n‐3 and 20:5n‐3 were higher in spring than in other seasons in PL and PE. There were nine sterols identified, with cholesterol being the predominant sterol, and other main ones were desmostersol/brassicasterol and 24‐methylenecholesterol. Proportions of other fatty acids in different lipid fractions and the sterol compositions as well also varied seasonally. There were subject to the seasonal variations. Differences in lipid content and composition, fatty acid composition in different lipid fractions may be caused by multiple factors such as lifecycle, sex, variation of plankton in different seasons and temperature, which could influence physiological activities and metabolism.
A differential scanning calorimetry study on the oxidation of C12‐C18 saturated fatty acids and their esters
Authors: Litwinienko G. , Daniluk A. , Kasprzycka‐Guttman T. 
Published: June 2007

AbstractThe autoxidation of lauric, myristic, palmitic, and stearic acids, their ethyl esters, and palmitic and stearic triglycerides was investigated by means of the isothermal and nonisothermal differential scanning calorimetry methods under oxygen flow. The activation energies of oxidation of all investigated compounds were similar (106.0–134.3 kJ/mol) and did not depend on length of the carbon chain. Kinetic parameters of start of the oxidation were similar for each investigated fatty acid and ester. Esterification of carboxyl group did not interfere with the reaction rate. The study showed good agreement between isothermal and nonisothermal data.
Reliability of the bromthymol blue method for color in virgin olive oils
Authors: Moyano M. J. , Melgosa M. , Alba J. , Hita E. , Heredia F. J. 
Published: June 2007

AbstractThe bromthymol blue (BTB) method is currently used for the assessment of color in olive and seed oils by visual comparison with standard solutions. Two BTB scales were prepared with 2 yr difference and compared, and the recent one was used to analyze 502 virgin olive oil samples, obtained by the Abencor® technique reproducing the industrial procedure. The temporal chromatic degradation of the BTB samples after 2 yr [3.93 Commission Internationale de l’Eclairage (CIE) 1976‐(L*a*b*) (CIELAB) units, on the average], as well as the small percentage of virgin olive oils matching the colors of the samples provided by the BTB scales (13.1% with a suprathreshold color tolerance of 1.52 CIELAB units), indicates the limitations of the BTB method. Linear regression models are proposed in order to compute with acceptable accuracy the BTB indices from chromaticparameters. The use of CIELAB for the specification and future studies on color in virgin olive oils is recommended.
Determination of iodine value of palm oil by fourier transform infrared spectroscopy
Authors: Che Man Y. B. , Setiowaty G. , van de Voort F. R. 
Published: June 2007

AbstractA rapid method for the quantitative determination of iodine value (IV) of palm oil products by FTIR transmission spectroscopy is described. A calibration standard was developed by blending palm stearin and superolein in specific ratios that covered a range of 27.9 to 65.3 IV units. The spectra of these standards was measured in the range between 3050 and 2984 cm−1, corresponding to the absorption band of=C‐H cis stretching vibration. A partial least squares calibration model for the prediction of IV was developed to quantify the IV of palm oil products. A validation approach was used to optimize the calibration with a correlation coefficient of R2=0.9995 and a standard error of prediction of 0.151. This study concludes that the FTIR transmission approach can be used to determine the IV of palm oil products with a total analysis time per sample of less than 2 min for liquid samples.
Synthesis of monoglycerides by glycerolysis of rapeseed oil using immobilized lipase
Authors: Elfman‐Börjesson Inger , Härröd Magnus 
Published: June 2007

AbstractReaction conditions for the synthesis of monoglycerides (MG) by enzyme‐catalyzed glycerolysis of rapeseed oil using Lipozyme® IM have been studied. Silica gel was used to adsorb the glycerol to overcome the problems of low glycerol solubility in the organic phase. An experimental design was used where temperature, time, the ratio of silica gel to glycerol (w/w), the water activity (a)w, the isooctane concentration, and the ratio of glycerol to triglycerides (mol/mol) were varied. Response surface methodology was used to evaluate initial reaction rate and yield for the different products. The best yield of MG achieved under the studied conditions was 17.4% (mol fatty acid in substance/total mol fatty acid in mixture) (75°C, 20 h, silica gel/glycerol 2:1, aw=0.17, 48% isooctane, glycerol/triglycerides 6:1). The same conditions yielded 36.8% diglycerides, 13.6% free fatty acids (FFA), and 36.9% triglycerides. This is at the same level as the equilibrium yield. The yield of MG is low compared to the final yield achieved with solid‐phase glycerolysis. However, in solid‐phase glycerolysis the reaction mixture becomes solid, and therefore the solid‐phase process is not suitable for industrial application. The formation of FFA was very fast compared to the synthesis of MG. Equilibrium for FFA was reached within 2 h, and the yield was strongly affected by the aw. Increasing aw greatly increased the formation of FFA. In the aw ratio 0.06–0.3, the yield of FFA increased from 4 to 19% while the yield of MG was nearly unaffected. As FFA is an undesired product, it is important to keep the aw as low as possible.
Concentration of phytosterols for analysis by supercritical fluid extraction
Authors: Snyder Janet M. , King Jerry W. , Taylor Scott L. , Neese Angela L. 
Published: June 2007

AbstractFractionation of sterols from plant lipid mixtures was accomplished using a multistep supercritical fluid extraction (SFE) procedure. Samples of seed oils, margarine, corn germ oil, and corn fiber oil were extracted to yield enriched phytosterol fractions. Supercritical fluid chromatography (SFC) was utilized to separate and determine the concentration of the plant sterols in the extracts from the various samples. The sterol concentration in the original samples varied from 2.2 mg/g in soybean oil to 13.2 mg/g in oil extracted from corn fiber. After the SFE‐based fractionation of the samples, the sterol concentration was increased to 64.4 mg/g in the extract from soybean oil and 166.2 mg/g in the extract from corn fiber oil. Oil extracted from corn bran, which measured 8.6 mg/g in the original oil, increased to 322.2 mg/g using the fractionation process. The benign conditions utilized by SFE and SFC proved to be effective for the analyses of these compounds without inducing degradation of the analytes.
Preparation of conjugated linoleic acid from safflower oil
Authors: Ma David W. L. , Wierzbicki Antoni A. , Field Catherine J. , Clandinin Michael T. 
Published: June 2007

AbstractSynthetically prepared mixtures of conjugated linoleic acid (CLA) are widely used in animal and cell culture studies to investigate the potential effects of the Δ9c, 11t‐18:2 isomer found in food products from ruminant animals. Alkali isomerization of linoleic acid is a common method used in the synthesis of a mixture of CLA isomers containing predominantly the Δ9c, 11t‐18:2 and Δ10t, 12c‐18:2 isomers. Some biological activity might also be mediated by the Δ10t, 12c‐18:2 isomer. Currently few published methodologies exist describing procedures for the enrichment of these two isomers. A method is described herein to take advantage of an inexpensive oil, safflower oil, for use in synthesis of CLA and a procedure to enrich the Δ10t, 12c‐18:2 isomer.
Palm olein quality parameter changes during industrial production of potato chips
Authors: du Plessis L. M. , Meredith A. J. 
Published: June 2007

AbstractNew legislation introduced in South Africa for the quality of used frying oils has resulted in the need to identify quicker, more suitable methods that correlate well with results from two official methods, namely, total polymerized glycerides and total polar components. Oil and product samples were taken at regular intervals during a commercial frying process in palm olein. Oil samples were analyzed for a number of different quality parameters viz. tocopherol content, dielectric constant, total polymerized glycerides, total polar components, tertiary butylhydroquinone (TBHQ) content, anisidine value, Rancimat induction period, and free fatty acid content, and the results statistically compared to results from official methods. Oil was expressed from product stored under accelerated conditions and analyzed for the same quality parameters. Fried product was also subjected to sensory evaluation to measure the degree of oil deterioration and sensory preference. The frying trial was successfully executed with refined, bleached, and deodorized palm olein and the frying oil used to a free fatty acid (FFA) content of 0.41%. Oil and product sampling were done at different FFA value levels. Frying oil quality was verified at the onset of the trial and at regular intervals. The frying oil total polar component value increased to approximately half of the limit set by the official regulation. This point was reached mainly due to the high starting value of the fresh oil. Frying oil total polymerized glycerides increased from below 1% to 2.1%. This increase is negligible when compared to the general trend for polyunsaturated oils. The alternative laboratory methods used for predicting oil quality can be rated as follows: total tocopherol content >dielectric constant >FFA >TBHQ content >anisidine value >Rancimat induction period. The first three methods correlated well with total polar component levels and it is recommended that the dielectric constant and FFA measurements be applied for monitoring oil condition during frying. It is possible that viscosity changes could be used for the monitoring of polyunsaturated frying oils. Evaluation of oil extracted from product revealed a negligible effect of non‐oil components on oil quality parameters. The same was observed when product was stored at −10°C and at 37°C.
Determination of optimal conditions for selected adsorbent combinations to recover used frying oils
Authors: Lin Song , Akoh Casimir C. , Reynolds A. Estes 
Published: June 2007

AbstractThe treatment of frying oils with adsorbents could practically extend the frying life of oils. Combined synthetic adsorbent treatment of used frying oils was studied the first time. The combinations of four commonly used filter aids: Britesorb (Br), Hubersorb 600 (HB), Frypowder (Fr), and Magnesol (Ma) were evaluated for frying oil recovery. AOCS official methods were used to evaluate their adsorptiveness, including free fatty acids (FFA), conjugated diene value, total polar components, oxidative stability index (OSI), and absorbance at 420 nm. The selected combinations HB+Ma+Fr and HB+Ma+Br exhibited consistent high recovery abilities on various used oil samples. A 3, 3, and 2% HB, Ma, and Fr, respectively, for the first combination (F), and 2, 3, and 2% HB, Ma, and Br, respectively, for the second combination (B) were the most effective. The optimal treatment duration was 6–9 min and 3–6 min for combinations F and B, respectively, which reduced FFA by 82.6–87.6%, absorbance by 26.8–32.6%, and Foodoil Sensor readings by 5.6–8.6%. Addition of antioxidant, such as 50 ppm butylated hydroxytoluene and 50 ppm propyl gallate, increased the OSI value by 48.9–80.8%. Such adsorbent combinations may be used in practical operation to extend frying life of frying oils and improve the healthy aspects of used frying oils.
Theoretical methods used in elucidating activity differences of phenolic antioxidants
Authors: Zhang Hong‐Yu 
Published: June 2007

AbstractThe effectiveness of the existing theoretical methods used in prediction of antioxidant activity, including structure‐activity relationships (SAR) and theoretical index, were evaluated. In most cases, it was found that the theoretical predictions were consistent with the experimental data. Although only one mechanism, free radical scavenging, was considered in the theories, the methods were valuable in predicting the activity of antioxidants to protect lipid oxidation.
Structural changes of sinapic acid during alkali‐induced air oxidation and the development of colored substances
Authors: Cai R. , Arntfield S. D. , Charlton J. L. 
Published: June 2007

AbstractStructural changes of sinapic acid were induced by air oxidation in aqueous solutions at pH 7–10 and followed by spectral and high‐performance liquid chromatographic (HPLC) analysis. Color properties of the sinapic acid solutions were determined by taking the transmittance spectra, calculating the Commission Internationale de l’Eclairage (CIE) 1931 tristimulus values, and converting to Hunter L a b values. Reaction rate constants for sinapic acid were determined by a kinetic study based on the quantitative results from HPLC analysis. These reactions were first order with respect to sinapic acid and fit the appropriate equation with a coefficient of R2 >0.97. Sinapic acid was converted to thomasidioic acid with reaction rate constants (k) of 8.54×10−6, 2.51×10−5, and 4.87×10−5 s−1 in phosphate‐boric acid buffers of pH 7, 8.5, and 10, respectively. Similar reactions in ammonium bicarbonate buffers were more than 10 times faster. With time, thomasidioic acid further converted to 2,6‐dimethoxy‐p‐benzoquinone and 6‐hydroxy‐5,7‐dimethoxy‐2‐naphthoic acid. Air oxidation of sinapic acid aqueous solutions caused darkening of the color for the system, with the 2,6‐dimethoxy‐p‐benzoquinone as a major color contributor.
The schistosome in the mammalian host: understanding the mechanisms of adaptation
Authors: KUSEL J. R. , AL-ADHAMI B. H. , DOENHOFF M. J. 
Published: June 2007

SUMMARYIn this review, we envisage the host environment, not as a hostile one, since the schistosome thrives there, but as one in which the relationship between the two organisms consists of constant communication, through signalling mechanisms involving sense organs, surface glycocalyx, surface membrane and internal organs of the parasite, with host fluids and cells. The surface and secretions of the schistosome egg have very different properties from those of other parasite stages, but adapted for the dispersal of the eggs and for the preservation of host liver function. We draw from studies of mammalian cells and other organisms to indicate how further work might be carried out on the signalling function of the surface glycocalyx, the raft structure of the surface and existence of pores in the surface membrane, the repair of the surface membrane, the role of the membrane structure in ion channel function (including recent work on the actin cytoskeleton and calcium channels) and the possible role of P-glycoproteins in the adaptation of the parasite to its environment. We are speculative in some areas, such as the suggestions that variability in surface properties of schistosomes may relate to the existence of membrane rafts and that parasite communities may exhibit quorum sensing. This speculative approach is adopted with the hope that future work on the whole organisms and their interactions will be encouraged.
Life trajectories and burden of adversity: mapping the developmental profiles of suicide mortality
Authors: SÉGUIN MONIQUE , LESAGE ALAIN , TURECKI GUSTAVO , BOUCHARD MÉLANIE , CHAWKY NADIA , TREMBLAY NANCY , DAIGLE FRANCE , GUY ANDRÉE 
Published: June 2007

ABSTRACTBackgroundLittle is known about differential suicide profiles across the life trajectory. This study introduces the life-course method in suicide research with the aim of refining the longitudinal and cumulative assessment of psychosocial factors by quantifying accumulation of burden over time in order to delineate distinctive pathways of completed suicide.MethodThe psychological autopsy method was used to obtain third-party information on consecutive suicides. Life-history calendar analysis served to arrive at an adversity score per 5-year segment that was then cluster-analysed and correlated to define victim profiles.ResultsTwo distinct life trajectories emerged: (1) individuals who experienced childhood traumas, developmental adversity and little protection were more likely to present concurrent psychiatric and Axis II disorders; and (2) individuals who experienced less adversity but seemed more reactive to later major difficulties.ConclusionsThe life calendar approach presented here in suicide research adds to the identification of life events, distal and recent, previously associated with suicide. It also quantifies the burden of adversity over the life course, defining two distinct profiles that could benefit from distinct targeted preventive intervention.
Memorabilities: enduring relationships, memories and abilities in dementia
Authors: BASSETT RAEWYN , GRAHAM JANICE E. 
Published: June 2007

ABSTRACTThis paper reports the findings of a one-year qualitative investigation of the memories and activities of people with mild to moderate Alzheimer's. We observed and interviewed 58 patient-carer dyads during home visits. The progression of the dementia symptoms was documented, and information was collected on social-relational events, as well as accounts of awareness, attention and anticipation, which are often neglected in research that focuses on the activities of daily living. The participants identified problems that were important to them; those with Alzheimer's disease were aware that they were not as attentive as they once had been, that they could no longer rely upon the memory of, or consciously recollect and relive, a past experience, and that the future was more difficult to anticipate. The participants' accounts describe relationships, memories and abilities – or ‘memor-abilities’ – of a past and their effects on their present and future. Our findings differ from clinical representations of memory located solely in the individual. Instead, memories are regarded as a synergistic package of both social and individual meanings that ‘leak’ between the two. What experimental psychologists interpret as systems and processes are played out in the everyday world of people with Alzheimer's disease as contextual, bounded and interdependent states of awareness, attention and anticipation. We maintain that memory is simultaneously individual and social, and that memorabilities are shared, co-constructed events and experiences in the past, present and future.
Orientation, opportunity and autonomy: why people work after state pension age in three areas of England
Authors: PARRY JANE , TAYLOR REBECCA F. 
Published: June 2007

ABSTRACTWith the central players in the United Kingdom policy debate on pensions schemes and funding advocating an extension to the average working life (or, more precisely, a rise in the age of ceasing work), this paper reports the findings of qualitative interviews with men and women at or approaching state pension age that examined what motivated some people to continue to work after that age. By exploring their work histories and orientations to work, the paper shows that people from different social and occupational backgrounds not only conceive work and retirement in different ways but also have contrasting opportunities to continue in occupations after retirement age. Their attitudes and the opportunities they encounter shape the decisions they make at state pension age. Distinctions are drawn between those who articulated an identity as a ‘worker’ and those who defined themselves as ‘professionals and creatives’, and within those categories, between the employed and self-employed. The paper elucidates the tensions between individuals' normative expectations of retirement, their desire for autonomy and flexibility in later life, and the financial and occupational reality of life after state pension age. We argue that understanding the different cultural meanings of work and retirement for different types of worker has implications for the design and implementation of policies to extend working life.
Severely obstructed totally anomalous pulmonary venous return with residual connection to the left atrium
Authors: Eng Loh Lik , Brown Katherine , Marek Jan 
Published: June 2007

AbstractTotally anomalous pulmonary venous return may present diagnostic difficulty to clinicians, as it often appears similar to severe neonatal pulmonary disease. We describe a neonate who presented with severely obstructed pulmonary venous return, but with a residual venous connection to the left atrium. The unusual anatomy confounded the diagnosis. To our knowledge, this particular permutation has not previously been described. Our experience indicates that echocardiographic interrogation should be repeated in cases where there is no response to conventional therapy, and all individual pulmonary veins should be observed carefully.
A prospective, randomized, double-blind, placebo controlled trial of beta-blockade in patients who have undergone surgical correction of tetralogy of Fallot
Authors: Norozi Kambiz , Bahlmann Jens , Raab Björn , Alpers Valentin , Arnhold Jan O. , Kuehne Titus , Klimes Katrin , Zoege Monika , Geyer Siegfried , Wessel Armin , Buchhorn Reiner 
Published: June 2007

AbstractAimsOur purpose was to evaluate the effect of a treatment over six months with bisoprolol on the surrogate parameters of N-Terminal-pro brain natriuretic peptide, subsequently to be described as brain natriuretic peptide, peak uptake of oxygen, and ventricular function assessed by magnetic resonance imaging in grown ups and adults who had undergone surgical correction of tetralogy of Fallot.Methods and resultsWe designed a prospective, randomized, double-blind, placebo controlled trial. We enrolled 33 patients, aged 30.9 plus or minus 9.5 years in either class 1 or 2 of the grading of the New York Heart Association class with both levels of brain natriuretic peptide greater than 100 pg/ml and a reduced peak uptake of oxygen less than 25 ml/kg/min. During treatment with Bisoprolol, the levels of brain natriuretic peptide increased significantly from 206 plus or minus 95 to 341 plus or minus 250 pg/ml (p< 0.05), and those of atrial natriuretic peptide from 4117 plus or minus 1837 to 5340 plus or minus 2102 fmol/ml (p = 0.0005). These measures remained unchanged in the group of patients receiving the placebo. Peak uptake of oxygen did not differ significantly in either group, nor did treatment have any significant effect on right and left ventricular volumes and ejection fractions as determined by magnetic resonance imaging. The clinical state as judged within the grading system of the New York Heart Association was also unchanged by beta-blockade.ConclusionBeta blockade with Bisoprolol seems to have no beneficial effect on asymptomatic or mildly symptomatic patients with right ventricular dysfunction secondary to repaired tetralogy of Fallot with residual pulmonary regurgitation and/or stenosis.