bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of SatSatSat and SatOSat on crystallization of model fat blends
Authors: Vereecken Jeroen , Foubert Imogen , Smith Kevin W. , Dewettinck Koen 
Published: January 2009

AbstractIn this study, the crystallization and melting properties of six different fat blends with the same saturated fat content (30%) but with a varying content of trisaturated and disaturated triacylglycerols were investigated using pulsed NMR, DSC and polarized light microscopy. Blends were either palmitic (P) or stearic (S) based, and were combinations of SatSatSat‐rich (Sat = saturated) and SatOSat‐rich (O = oleic) vegetable oils with high‐oleic sunflower oil. The DSC results suggested that PPP forms mixed crystals with POP, leading to a better seeding of the crystallization process than did SSS with SOS. Some blends showed a two‐step crystallization, which can be explained by polymorphism. Stop‐and‐return DSC results suggested an initial crystallization into an unstable polymorph followed by polymorphic transformation during the crystallization for those blends with significant amounts of SatSatSat. Polymorphic transformation was not seen for the blends with low SatSatSat. However, the microstructure of such blends changed dramatically during storage, while the microstructure of the blends with the higher SatSatSat content did not.
On the quality control of ‘olive paste’, a specialty based on olives and olive oil
Authors: Anniva Christina , Tsimidou Maria Z. 
Published: January 2009

Abstract‘Olive paste’ is a preserved food gaining popularity as a gourmet product. Its quality depends on that of the major ingredients, table olives (green or black) and virgin olive oil, as well as on the changes occurring to the constituents of the latter during preparation and storage. In this view, our attention was focused on the characteristics of the lipid fraction (l.f.) of a great number of commercial products after a careful search in retail markets and the web. Ultraviolet absorbance values (K232, K270) of the l.f., a criterion set for edible and non‐edible olive oil oxidative status due to paste heat treatment during pasteurization, could not support the label information regarding the quality of the oil used. On the contrary, the content of α‐tocopherol (˜250 mg/kg l.f. or ˜50 mg/kg paste) was a strong indication of good‐quality major ingredients. Within each brand, consistency with labeling was checked through squalene (higher content in products containing higher amounts of olive oil) or β‐carotene determination (higher levels in preparations containing red pepper). For green olive paste samples, the values of the ratio pheophytin a/pyropheophytin a may be used to monitor the shelf life of the product. The findings support routine quality control of the new product.
Effect of ingredients on oxidative stability of fish oil‐enriched drinking yoghurt
Authors: Nielsen Nina Skall , Klein Anna , Jacobsen Charlotte 
Published: January 2009

AbstractThe oxidative stabilities of fish oil‐enriched milk and fish oil‐enriched drinking yoghurt were compared by following the development of lipid oxidation in plain milk, plain yoghurt and yoghurt to which ingredients present in drinking yoghurt were added one by one. All samples were enriched with 1 wt‐% fish oil. After 3 weeks of storage, development of peroxide values, volatile secondary oxidation products and fishy off‐flavors were much more pronounced in the milk compared to any of the yoghurt samples, irrespective of any added ingredients used to prepare flavored drinking yoghurt. Thus, pectin, citric acid or glucono‐delta‐lactone did not affect the oxidative stability of fish oil‐enriched yoghurt emulsions. Furthermore, the fruit preparation and added sugar did not lead to increased antioxidative activity. It is concluded that yoghurt as the dairy component in the fish oil‐enriched emulsion was responsible for the remarkably high oxidative stability and was able to protect the n‐3 PUFA against oxidative deterioration. It should be considered that this strong antioxidative effect of yoghurt might mask potential antioxidative effects of the other ingredients in the drinking yoghurt.
DFT Studies on Double Hydrogen Bond Catalysis of Reactions of Distinct Polarity
Authors: Gómez‐Bengoa Enrique 
Published: January 2009

AbstractThe Diels–Alder cycloaddition and the enamine‐aldol reactions catalyzed by double‐site hydrogen‐bond donors were computationally studied at the B3LYP and MP2/6‐311++G** levels. The comparison of bifurcated and cooperative H‐bonding activation of the electrophile in both reactions with 1,3‐propanediol, 1,4‐butanediol, glycolic acid and two molecules of methanol strongly suggests that the activation mode depends on the electronic features of the carbonyl oxygen atom in the H‐bond acceptor. The bifurcated arrangement of the hydrogen‐bond donors is predicted to be favoured as the polarity of the reaction increases. Consequently, the transition states of the Diels–Alder reaction are better stabilized by a cooperative interaction with the diols and those of the more polar enamine‐aldol reaction by a bifurcated interaction. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Integrated microdevice for preconcentration and separation of a wide variety of compounds by electrochromatography
Authors: Proczek Gaelle , Augustin Violaine , Descroix Stephanie , Hennion Marie‐Claire 
Published: January 2009

AbstractAn integrated microdevice was developed to couple on‐chip SPE to separation by channel electrochromatography. An acrylate‐based monolith was synthesized within a glass microdevice by photoinitiated polymerization. It was used for both separation and preconcentration by direct injection on the head of the stationary phase or by confining the preconcentration step in a given zone of the stationary phase. The composition of the polymerization mixture was chosen to achieve a monolithic material containing both hydrophobic and charged moieties to ensure an electroosmotic flow for separation. As a consequence the extraction procedure occurs via hydrophobic and ionic interactions. Neutral, ionizable and charged compounds were successfully preconcentrated and separated within the microdevice through electrochromatographic mechanisms, highlighting the versatility of this device. The performance of the integrated microdevice was demonstrated with the preconcentration and separation of a mixture of PAHs for which a signal enhancement factor (SEF) of 270 was achieved within 120 s of preconcentration. In the case of charged and ionizable compounds, according to the electrolyte composition, contributions of both reverse‐phase and ion‐exchange mechanisms were used to perform effective electrochromatographic preconcentration. A SEF of 250 was obtained for the model‐charged compound within 20 s of preconcentration. Finally, the potentials of on‐chip preconcentrate and separate both neutral and ionized compounds have been demonstrated using a mixture of model compounds.
CE‐based detection of methicillin‐resistant Staphylococcus aureus
Authors: Naikare Hemant , Ramachandran Akhilesh , Goad David , Clarke Jean , Clarke Cyril 
Published: January 2009

AbstractRapid and sensitive detection of methicillin‐resistant Staphylococcus aureus is crucial for effective treatment and control of clinical infections caused by this bacterium. The goal of this study is to develop a CE‐based detection method for multiplexed identification of a femA sequence specific for S. aureus and a unique mecA sequence encoding methicillin resistance. Blood samples spiked with known concentrations of bacteria were used for testing. Crude cell lysates were prepared by treating the spiked blood samples with DNazol Direct reagent and used as the template for isothermal amplification of mecA and femA genes. The amplified gene products then underwent a cycling probe reaction (CPR)‐based assay to generate a short fluorophore‐labeled oligonucleotide for detection in a CZE‐LIF system. The assay enables a gene‐specific fluorophore‐labeled DNA–RNA–DNA chimeric probe to hybridize with complementary target in the presence of RNase H enzyme. The RNase H enzyme specifically cleaves probe RNA residues of the duplex, releasing a fluorophore fragment for detection and the target for recycling and hybridization with another chimeric probe. Intact and cleaved probe fragments were separated and detected using a CZE‐LIF system. The limit of detection for isothermal amplification and CPR‐CZE‐LIF was ∼104 colony‐forming units of bacteria/mL of blood. This method accurately detects methicillin‐resistant S. aureus within 3 h.
Selective enrichment of albumin in biological samples by CE using segmental filling with sodium octyl sulfate in the background electrolyte
Authors: Lin Chin‐Yu , Tseng Wei‐Lung 
Published: January 2009

AbstractThis paper shows that in CE, the peak efficiency and effective electrophoretic mobility of HSA and BSA were significantly enhanced by using a short plug (8 nL) of 1% w/w sodium octyl sulfate (SOS) and 1% w/v dextran sulfate as the additive. However, under identical conditions, other proteins did not exhibit the same phenomena. When the concentration of SOS was increased to 1.0% w/w SOS, a broad peak that corresponded to HSA transformed to a sharp peak. When the SOS concentration was more than 3.0% w/w, there was no shift in the effective electrophoretic mobility of HSA (10 μM), indicating that the binding of SOS to HSA is saturated. Through the specific interaction between SOS and HSA, the selective sweeping of HSA was accomplished using a short plug (24 nL) of 1% w/w SOS, followed by the injection of 190 nL of the sample. The excellent peak efficiency was still obtained for HSA and BSA upon the injection of a large‐volume sample. As a result, the LOD for HSA (S/N=3)was 0.1 nM. In contrast to the normal injection without the SOS plug, approximately, a 4000‐fold increase in the sensitivity of HSA was obtained by using the sweeping method. The proposed method has been successfully applied for the quantification of HSA in urine and erythrocytes as well as the quantification of BSA in milk.
The combination of flow injection with electrophoresis using capillaries and chips
Authors: Lü Wen‐juan , Chen Yong‐lei , Zhu Jin‐hua , Chen Xing‐guo 
Published: January 2009

AbstractThe technique of combined flow injection CE (FI‐CE) integrates the essential favorable merits of FI and CE. It utilizes the various excellent on‐line sample pretreatments and preconcentration (such as cloud point extraction, SPE, ion‐exchange, dynamic pH junction and head‐column field‐amplified sample stacking technique) of FI, which has the advantages of high speed, accuracy, precision and avoiding manual handling of sample and reagents. Therefore, the coupling of FI‐CE is an attractive technique; it can significantly expand the application of CE and has achieved many publications since its first appearance. The basic principles, instrumental developments and applications of FI‐CE system from 2006 to 2008 are reviewed.
Development of an in‐capillary derivatization method by CE for the determination of chiral amino acids in dietary supplements and wines
Authors: Martínez‐Girón Ana Belén , García‐Ruiz Carmen , Crego Antonio L. , Marina Maria Luisa 
Published: January 2009

AbstractA fast in‐capillary derivatization method by CE with 6‐aminoquinolyl‐N‐hydroxysuccinimidyl carbamate was developed for the first time for the determination of amino acid enantiomers (arginine, lysine, and ornithine) in dietary supplements and wines. Because of the initial current problems due to the formation of precipitates into the capillary during the derivatization reaction, a washing step with an organic solvent as DMSO between injections was necessary. Different approaches were also investigated to enhance the sensitivity of detection. A derivatization procedure, where plugs of ACN, derivatizing agent (10 mM 6‐aminoquinolyl‐N‐hydroxysuccinimidyl carbamate), and sample in borate (1:1 v/v) were injected in tandem (2, 3, and 6 s, respectively, at 50 mbar), was selected because it enabled to obtain the most sensitive and reproducible results. Appropriate analytical characteristics (linearity, LOD and LOQ, precision, absence of matrix interferences, and accuracy) were obtained for this method. Finally, the optimized method was successfully applied to the determination of the enantiomers of arginine, lysine, and ornithine in food samples of different complexities (dietary supplements and wines).
Separation and detection of isoquinoline alkaloids using MEEKC coupled with field‐amplified sample injection induced by ACN
Authors: Yu Li‐Shuang , Xu Xue‐Qin , Huang Lu , Lin Jin‐Ming , Chen Guo‐Nan 
Published: January 2009

AbstractNew methods based on MEEKC coupling with field‐amplified sample injection (FASI) induced by ACN were proposed for five isoquinoline alkaloids (berberine, palmatine, jatrorrhizine, sinomenine and homoharringtonine) in no salt and high salt sample solution (HS). For the separation of five isoquinoline alkaloids, a running buffer composed of 18 mM sodium cholate, 2.4% v/v butan‐1‐ol, 0.6% v/v ethyl acetate, 10% v/v (or 30% v/v) methanol and 87.0% v/v (or 67% v/v) 5 mM Na2B4O7∼10 mM NaH2PO4 buffer (pH 7.5) was developed. In order to improve the sensitivity, FASI induced by ACN was applied to increase the detection sensitivity. The detection limit was found to be as low as 0.0002 μg/mL in no salt sample solution and 0.062 μg/mL in HS. The method has been applied for the analysis of human urine spiked with analytes, and the assay results were proved to be satisfactory, and also the determination of berberine in urine sample after oral administration berberine.
Structures and modulation algorithms of direct ac/ac converters with two legs and three legs for two‐phase systems
Authors: Kwak Sangshin 
Published: January 2009

AbstractTwo‐phase ac/ac matrix converter configurations are presented based on direct power conversion processes from three‐phase input ac supplies to two‐phase output ac loads. Two types of two‐phase matrix converter topologies, utilizing the standard matrix converter configuration, are introduced with two‐leg and three‐leg based structures. Pulse width modulation (PWM) strategies with high‐frequency composition for the two‐leg and the three‐leg based two‐phase matrix converters are developed to synthesize sinusoidal output waveforms of two‐phase loads from time‐varying input ac voltages. Grounded on the developed modulation algorithms, the presented matrix converters directly generate controllable two‐phase output voltages from sinusoidal input voltages with no intermediate dc conversion and concomittant dc‐link elements. The proposed matrix converters can provide sinusoidal output current/voltage waveforms with independently controlled magnitude and 90° phase angle to two‐phase loads. Thus, the converters are effective for both balanced and unbalanced two‐phase loads. The presented two‐phase operations with the standard matrix converter structures add the versatility for the matrix converter systems to function in multi‐phase loads as a universal converter. Simulation and experimental results are presented to verify the developed modulation techniques and the converter configurations for the two‐phase matrix converters. Copyright © 2009 John Wiley & Sons, Ltd.
A Half Cell Study of Performance and Degradation of Oxygen Reduction Catalysts for Application in Low Temperature Fuel Cells
Authors: Stassi A. , Modica E. , Antonucci V. , Aricò A. S. 
Published: January 2009

AbstractAn investigation of preleached PtCo/C catalysts for the oxygen reduction reaction (ORR) was carried out at 75 °C in sulphuric acid electrolyte by using a gas‐fed half‐cell in order to evaluate their stability characteristics. The influence of different leaching methods on catalyst stability was studied. Accelerated degradation tests were utilised to investigate the influence of platinum dissolution, sintering and carbon black corrosion. The catalysts behaviour was analysed in terms of performance loss before and after the electrochemical ageing. The PtCo catalyst preleached with perchloric acid showed a better stability than other catalysts in the specific Platinum degradation test; whereas, a significant degradation in the carbon corrosion test was observed for all catalysts.
Association between cognition and daily life functioning in dementia subtypes
Authors: Bouwens Sharon F. M. , van Heugten Caroline M. , Verhey Frans R. J. 
Published: January 2009

AbstractObjectiveTo investigate the association between cognition and daily life functioning in dementia subtypes.MethodsCross‐sectional data were used from 615 patients with dementia who were referred to the Maastricht Memory Clinic of the Maastricht University Medical Centre. Pearson correlation coefficients were calculated between the Mini‐Mental State Examination (MMSE; to measure cognitive status) and the Blessed Dementia Scale (BDS; to measure daily life functioning) for the following types of dementia: Alzheimer's Disease (AD, n = 442); Vascular dementia (VaD, n = 113); frontotemporal dementia (FTD, n = 18); Parkinson's dementia (PD, n = 21); and primary progressive aphasia (PPA, n = 21). One‐way ANOVA was used to test differences in age, MMSE scores and BDS scores across dementia subtypes.ResultsScores on the MMSE showed strong correlation with BDS scores in cases of FTD (r = −0.80); moderate correlation in cases of AD, VaD, and PD (range r = −0.50–0.60); while no correlation was found in PPA cases.ConclusionsThe association between cognition and daily life functioning varied among dementia subtypes for AD, VaD, FTD and PD. Furthermore, the overall scores on both domains differ between dementia subtypes, indicating that different types of dementia are characterized by a specific pattern of cognitive status and daily life functioning. These findings underline the need for multidomain assessment in patients with dementia. Copyright © 2009 John Wiley & Sons, Ltd.
Toxicity and survival outcomes of hyperfractionated split‐course reirradiation and daily concurrent chemotherapy in locoregionally recurrent, previously irradiated head and neck cancers
Authors: Watkins John M. , Shirai Keisuke S. , Wahlquist Amy E. , Stuart Robert K. , Chaudhary Uzair B. , Garrett‐Mayer Elizabeth , Day Terry A. , Gillespie M. Boyd , Sharma Anand K. 
Published: January 2009

AbstractBackground.Reirradiation of locoregionally recurrent, previously irradiated head/neck cancer may be considered in situations of unresectability, medical inoperability, or adverse pathologic features found at salvage resection.Methods.Retrospective cohort analysis of toxicity and survival outcomes in locoregionally recurrent, previously irradiated patients with head/neck cancer treated with hyperfractionated split‐course radiotherapy and concurrent chemotherapy.Results.Between March 1998 and September 2006, 39 patients initiated reirradiation at median of 2.3 years (range, 0.5–19) following prior radiotherapy. At median survivor follow‐up of 24.5 months (range, 3–63.9), 10 patients are alive without evidence of disease. Median survival is 19.0 months, with estimated 1‐, 2‐, and 3‐year overall survivals of 60.1%, 45.1%, and 22.7%, respectively. Locoregional failure was the predominant site of postreirradiation recurrence. Male sex, total radiotherapy dose, cycles of chemotherapy completed, and clinical response were associated with improved overall survival.Conclusions.Reirradiation can offer long‐term survival for patients with recurrent, previously irradiated head/neck cancers. © 2009 Wiley Periodicals, Inc. Head Neck, 2009
Role of chest CT in staging of oropharyngeal cancer: A systematic review
Authors: McLeod Niall M. H. , Jess Alex , Anand Rajiv , Tilley Elisabeth , Higgins Bernie , Brennan Peter A. 
Published: January 2009

AbstractBackground.The prevalence of synchronous or metastatic tumors in patients with head and neck squamous cell carcinoma (HNSCC) ranges from 6% to 20% and has implications for prognosis and management of the primary disease. There is no consensus about the role of chest CT prior to definitive treatment patients with HNSCC.Methods.A systematic review of all chest CT studies in relation to HNSCC was performed, together with a review of our local database.Results.Twenty‐four studies were identified in addition to our local data. Prevalence of positive chest CT was 7.93%. Patients were significantly more likely to have a positive chest CT with N2 or N3 neck disease (p = .0062) and stage III or IV disease (p = .0001), and significantly less likely with tumors of the oral cavity (p = .0007).Conclusion.We advocate chest CT as part of the initial investigations for patients with HNSCC. © 2009 Wiley Periodicals, Inc. Head Neck, 2009
Reduced excitability in the dentate gyrus network of βIV‐spectrin mutant mice in vivo
Authors: Winkels Raphael , Jedlicka Peter , Weise Felix K. , Schultz Christian , Deller Thomas , Schwarzacher Stephan W. 
Published: January 2009

AbstractThe submembrane cytoskeletal meshwork of the axon contains the scaffolding protein βIV‐spectrin. It provides mechanical support for the axon and anchors membrane proteins. Quivering (qv3j) mice lack functional βIV‐spectrin and have reduced voltage‐gated sodium channel (VGSC) immunoreactivity at the axon initial segment and nodes of Ranvier. Because VGSCs are critically involved in action potential generation and conduction, we hypothesized that qv3j mice should also show functional deficits at the network level. To test this hypothesis, we investigated granule cell function in the dentate gyrus of anesthetized qv3j mice after electrical stimulation of the perforant path in vivo. This revealed an impaired input‐output relationship between stimulus intensity and granule cell population spikes and an enhanced paired‐pulse inhibition of population spikes, indicating a reduced ability of granule cells to generate action potentials and decreased network excitability. In contrast, the input‐output curve for evoked field excitatory postsynaptic potentials (fEPSPs) and paired‐pulse facilitation of fEPSPs were unchanged, suggesting normal excitatory synaptic transmission at perforant path‐granule cell synapses in qv3j mutants. To corroborate our findings, we analyzed the influence of VGSC density reduction on dentate network activity using an established computational model of the dentate gyrus network. This in silico approach confirmed that the loss of VGSCs is sufficient to explain the electrophysiological changes observed in qv3j mice. Taken together, our findings demonstrate that βIV‐spectrin is required for normal granule cell firing and for physiological levels of network excitability in the mouse dentate gyrus in vivo. © 2009 Wiley‐Liss, Inc.