bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phenolic diterpene and α‐tocopherol contents in leaf extracts of 60 Salvia species
Authors: Abreu Maria E , Müller Maren , Alegre Leonor , Munné‐Bosch Sergi 
Published: October 2008

AbstractBACKGROUND: Carnosic acid and carnosol, the two major phenolic diterpenes present in rosemary and sage extracts, have received attention in food science and biomedicine because of their potent antioxidant properties. In plants, these compounds have been identified as being present in some species of the family Lamiaceae, but there is still little information about their distribution within the plant kingdom. The aim of the present study was to gain a better understanding of the occurrence of these compounds within leaf extracts of the genus Salvia and also to examine to what extent leaf senescence may influence their accumulation in relation to that of α‐tocopherol (vitamin E).RESULTS: Methanolic leaf extracts of 60 species of the genus Salvia were tested for the presence of carnosic acid and carnosol. These two diterpenes were detected in 48 and 27 species respectively. In contrast, α‐tocopherol was present in all species examined. Leaf senescence in Salvia officinalis resulted in α‐tocopherol increases by up to 5.5‐fold, while carnosic acid and carnosol increased by up to 18 and 290% respectively. Isorosmanol, an oxidation product of carnosic acid, increased by up to 2.1‐fold in senescing leaves.CONCLUSION: It was found that, while α‐tocopherol is ubiquitous in the genus Salvia, phenolic diterpenes are present in several but not all species. It was also shown that leaf senescence may increase the yield of both phenolic diterpenes and α‐tocopherol in sage extracts. Copyright © 2008 Society of Chemical Industry
Protein interactions with cyanidin‐3‐glucoside and its influence on α‐amylase activity
Authors: Wiese Stefanie , Gärtner Sonja , Rawel Harshadrai M. , Winterhalter Peter , Kulling Sabine E. 
Published: October 2008

AbstractBACKGROUND: Recent studies indicate that the bioavailability of anthocyanins is extremely low. One of the possible reasons could be their binding to proteins. Therefore, the binding affinity of cyanidin‐3‐glucoside (Cy3glc) to HSA and α‐amylase was investigated by the quenching of protein tryptophan fluorescence. From data obtained, the binding constants and the free Gibbs energy were calculated. The changes in conformation of the proteins tested were studied with circular dichroism and the influence of binding on α‐amylase activity determined.RESULTS: Cy3glc quenched the tryptophan fluorescence and upon ligand binding a change in protein structure was observed related to the corresponding decrease in the α‐amylase activity. The association constants of 25 to 77 × 103 L mol−1 were calculated for different proteins, indicating weak interactions of non‐covalent nature. Competitive binding with HSA in the presence of 8‐anilino‐1‐naphthalene sulfonic acid suggest involvement of hydrophobic interactions, in the case of HSA the possible site being subdomain IIA.CONCLUSION: The strongest affinity of Cy3glc for HSA being at pH 7 underlines its potential in transport and distribution of the phenolic compounds in organisms. An influence on salivary amylase activity is possible when drinking berry juices with high anthocyanins content. Copyright © 2008 Society of Chemical Industry
Chemical composition and in vitro control of agricultural plant pathogens by the essential oil and various extracts of Nandina domestica Thunb.
Authors: Bajpai Vivek K , Lee Tae Jong , Kang Sun Chul 
Published: October 2008

AbstractBACKGROUND: The aims of this study were to examine the chemical composition of the essential oil isolated from the floral parts of Nandina domestica Thunb. by hydrodistillation, and to test the efficacy of essential oil and various leaf extracts (n‐hexane, chloroform, ethyl acetate and methanol) as an antifungal potential against a panel of agricultural plant pathogens.RESULTS: The GC‐MS analysis determined that 79 compounds, which represented 87.06% of total oil, were present in the oil containing mainly 1‐indolizino carbazole (19.65%), 2‐pentanone (16.4%), mono phenol (12.1%), aziridine (9.01%), methylcarbinol (4.6%), ethanone (3.3%), furfural (2.96%), 3,5‐dimethylpyrazole (1.29%) and 2(5H)‐furanone (1.32%). The oil (1000 ppm disc−1) and the leaf extracts (1500 ppm disc−1) revealed remarkable antifungal effect against Fusarium oxysporum, Fusarium solani, Phytophthora capsici, Colletotrichum capsici, Sclerotinia sclerotiorum, Botrytis cinerea and Rhizoctonia solani in the growth inhibition range of 53.3–64.3% and 33.3–56.0%, respectively, along with their respective values for mimimum inhibitory concentration (MIC) ranging from 125 to 1000 µg mL−1 and 500 to 2000 µg mL−1. The values for minimal fungicidal concentration (MFC) of the oil and extracts were obtained in the range of 125 to 1000 µg mL−1 and 500 to 2000 µg mL−1, respectively. The essential oil also had a strong detrimental effect on spore germination of all the plant pathogens tested along with concentration as well as time‐dependent kinetic inhibition of B. cinerea.CONCLUSION: The results obtained in this study demonstrate that N. domestica mediated oil and extracts could become potential alternatives to synthetic fungicides for controlling certain important agricultural plant pathogenic fungi. Copyright © 2008 Society of Chemical Industry
Determination of estrogens and their metabolites in water using C30 SPE‐LC‐MS
Authors: Yan Wei , Zhao Lixia , Feng Qinzhong , Lin Jin‐Ming 
Published: October 2008

AbstractTriacontyl bonded silica (C30) material was applied as solid‐phase extraction (SPE) sorbent and an SPE‐LC‐MS method was established for the determination of eight estrogens and their metabolites in water samples. Compared to commercial C18 SPE cartridge, the performance of C30 was evaluated in various important SPE conditions, such as sorbent mass, elution solvent and its volume, loading flow rate, and sample loading volume. The results showed a superior performance of C30–C18 by the shorter treatment time and fewer required elution solvent. In the optimum conditions, the results showed good recoveries (80.5–109.4%), excellent linear relationships (0.02–1 ng/mL, except 2‐MeO‐E2), high precisions (lower than 10.0% RSD for both low and high spiked concentration), and low LODs (1–16 ng/L). Method validation using C30 packed cartridge was also testified with spiked real water samples, including tap water and river water. Satisfy results demonstrated the feasibility of C30 SPE to the analysis for real environmental waters.
Identification of collagen types in tissues using HPLC‐MS/MS
Authors: Pataridis Statis , Eckhardt Adam , Mikulíková Katerina , Sedláková Pavla , Mikšík Ivan 
Published: October 2008

AbstractA method for the determination and quantification of collagen types I–V in rat tissues has been developed. This method is based on collagen fragmentation by cyanogen bromide followed by trypsin digestion. After that, HPLC‐MS/MS (HPLC coupled to an IT mass spectrometer) analyses of the resulting peptide mixtures (peptide maps) were performed. Specific peptides for each collagen type were selected. According to online databases, these peptides are present in human, bovine, and rat collagens. As a result, this method can be potentially applied to other species' tissues as well, such as human tissues, and provides a universal and simple method of quantifying collagen types. The applicability of this method for analyzing collagen types was demonstrated on rat tissues (skin, tendon, and aorta).
Separation and analysis of acylglycerols by chromatographic methods
Authors: De Clercq Nathalie , Foubert Imogen , Dewettinck Koen 
Published: October 2008

AbstractMany studies in lipid analysis require separation and isolation of various acylglycerol classes for subsequent analysis, research and use. Different chromatographic techniques can be used for this purpose. The most desirable method should be rapid, convenient and inexpensive, provide a high yield and supply as much information as possible about each compound with minimal interference or overlaps with other similar components. This article discusses some methods that can be used to separate acylglycerols.
Influence of Clay Modification on the Properties of Resol Nanocomposites
Authors: Manfredi Liliana B. , Puglia Debora , Tomasucci Annalisa , Kenny José M. , Vázquez Analía 
Published: October 2008

AbstractTwo organically modified (Cloisite® 30B and 10A) and one unmodified clay (Cloisite® Na) were added to a resol‐type phenolic prepolymer. The modified montmorillonites showed a better dispersion in the prepolymer. The dispersion of the clay, the chemical structure as well as the thermal degradation behavior of the cured polymer and nanocomposites were studied. It was observed that the addition of Cloisite® Na leads to enhanced crosslinking of the cured polymer, leading to a higher activation energy for thermal degradation. The resol with Cloisite® 10A contained a higher percentage of voids, which seems to be one of the major factors that reduce hardness and adhesive strength when the nanocomposite was applied to a metal substrate.magnified image
An analogue method for simultaneous prediction of surface weather parameters at a specific location in the Western Himalaya in India
Authors: Singh D. , Dimri A. P. , Ganju A. 
Published: October 2008

AbstractAvalanches in the Western Himalaya cause loss of life and damage property every year. To reduce such losses avalanche forecasting is practiced. This technique requires information about various surface weather parameters at least a couple of days in advance. In view of the above requirement, an analogue method has been employed to predict maximum, minimum and ambient temperatures, average wind speed, surface pressure and relative humidity at a specific location in the Western Himalaya. Predictions for surface weather parameters 3 days in advance have been attempted using information of past synoptic situations corresponding to the current situation searched from a database through Euclidean distance. Surface weather observations of the past 16 winters (1989–1990 to 2005–2006) have been used to develop the model. The model has been tested with independent data set of 166 days of winter 2006–2007. The forecast accuracy for maximum, minimum and ambient temperature falls in the range 74.7–85.5, 64.2–81.8 and 58.5–79.9% within an error limit of 3 °C for day 1, day 2 and day 3. Forecast accuracy for prediction of average wind speed is in the range 65.7–70.9% and it is in the range 73.7–82.5% for atmospheric pressure with same error limit as temperature (with respective units) for day 1, day 2 and day 3. Accuracy for the prediction of relative humidity is in the range 58.5–69.3%, within an error limit of 20% for all three days. The root mean square error (RMSE) and mean absolute error (MAE) of each weather parameter have been computed to test the prediction error of the model. The results suggest that the analogue method holds promise for simultaneous prediction of surface weather parameters with reasonable accuracy. Predicted surface weather parameters have been used for assessing future avalanche situations with reasonable confidence. Copyright © 2008 Royal Meteorological Society
Modulation of the postprandial phase by β‐glucan in overweight subjects: Effects on glucose and insulin kinetics
Authors: Nazare Julie‐Anne , Normand Sylvie , Oste Triantafyllou Angeliki , Brac de la Perrière Aude , Desage Michel , Laville Martine 
Published: October 2008

AbstractDecreasing the postprandial glucose response is potentially of major importance to public health when low‐glycemic index or high‐fibre content foods are associated with a decreased risk of diabetes. We investigated in overweight subjects the effect of adding β‐glucan (BG) to a polenta (Pol) meal on postprandial metabolism and glucose bioavailability using stable isotopes. In this single‐blind, randomized, crossover trial, 12 subjects ate two meals containing Pol with (Pol + BG) or without (Pol) 5 g BG. Concentrations of glucose, insulin, C‐peptide, nonesterified fatty acids, triacylglycerol, total and exogenous glucose kinetics were assessed for 6 h postprandially. The kinetics of total and exogenous glucose importantly differed between the meals, but not the quantity of total and exogenous glucose appearing in plasma. Less total and exogenous glucose appeared during the first 120 min after the Pol + BG meal; the phenomenon was then reversed (both p < 0.0001). After 120 min, glucose and insulin responses declined, but remained higher after the Pol + BG meal (p < 0.05) in parallel to the inhibition of lipolysis. The endogenous glucose production (EGP) was significantly more inhibited after the Pol + BG meal. The addition of BG slowed the appearance of glucose in plasma, resulting in longer‐lasting insulin secretion which exerted a prolonged inhibition of EGP and lipolysis.
Regulation of β‐catenin and connexin‐43 expression: Targets for sphingolipids in colon cancer prevention
Authors: Simon Kirk W. , Roberts Paul C. , Vespremi Michael J. , Manchen Steve , Schmelz Eva M. 
Published: October 2008

AbstractSphingolipid metabolites are generated throughout the intestinal tract after hydrolysis of orally administered complex sphingolipids and significantly suppress colon cancer in carcinogen‐treated CF1 mice. In the present study, the mechanisms of tumor suppression by dietary sphingolipids were investigated. Changes in select genes that are critical in early stages of colon cancer were analyzed in the colonic mucosa of dimethylhydrazine‐treated CF1 mice fed AIN76A diet with or without 0.05% sphingomyelin (SM). Supplementation with SM did not significantly alter mRNA levels of most of the selected genes. However, a downregulation of β‐catenin (p = 0.007) and increased protein levels of connexin‐43 (p = 0.017) and Bcl‐2 (p = 0.033) were observed in SM‐fed animals. This suggests that sphingolipids may be regulating specific post‐transcriptional events to reverse aberrant expression of individual proteins. Since the dysregulation of β‐catenin metabolism and its transcriptional activity in addition to a decreased intercellular communication has been causally linked to the development of colon cancer while a low Bcl‐2 expression is associated with a worse prognosis in colon cancer, the reversal of these early changes may be important events in the prevention of colon cancer by orally administered sphingolipids, and may provide specific molecular biomarkers for sphingolipid efficacy in vivo.
Acute urodynamic effects of percutaneous posterior tibial nerve stimulation on neurogenic detrusor overactivity in patients with Parkinson's disease
Authors: Kabay Sibel Canbaz , Kabay Sahin , Yucel Mehmet , Ozden Hilmi 
Published: October 2008

AbstractAimsLower urinary tract dysfunction is often occurs in patients with Parkinson's disease (PD), that is primarily induced by neurogenic detrusor overactivity (NDO) and negatively effect the quality of the patient's life. The aim of this study is to evaluate the acute effects of posterior tibial nerve stimulation (PTNS) on the urodynamic findings in the PD patients with NDO.MethodsThirty‐two patients with PD (19 [59.3%] men and 13 [40.6%] women) with NDO were included in the study. Mean age of the patients was 64.2 ± 8.7 years (range 44–78). Urodynamic studies before and during PTNS were performed. Electrical stimulation was applied unilaterally from the medial malleolus and posterior to the edge of the tibia by using charge‐compensated 200 µsec pulses with a pulse rate of 20 Hz. Mean first involuntary detrusor (1st IDCV) contractions and means maximum cystometric capacity (MCC) before and during PTNS was compared.ResultsMean 1st IDCV on standard cystometry was 145.2 ± 41.1 (55–265) ml, while it was 244.7 ± 51.7 (145–390) ml during PTNS. MCC on standard cystometry was 204.8 ± 40.5 (115–320) ml, while it was 301.2 ± 51.5 (230–395) ml during stimulation. Mean 1st IDC and mean MCC were significantly improved during PTNS.ConclusionsThese results have demonstrated the objective acute effect of PTNS on urodynamic parameters. PTNS is acutely effective to suppress detrusor overactivity in PD patients. Neurourol. Urodynam. 28:62–67, 2009. © 2008 Wiley‐Liss, Inc.
1H and 31P NMR studies indicate reduced bile constituents in patients with biliary obstruction and infection
Authors: Bala Lakshmi , Tripathi Pratima , Bhatt Ganesh , Das Kshaunish , Roy Raja , Choudhuri Gourdas , Khetrapal C. L. 
Published: October 2008

AbstractPatients with extrahepatic biliary obstruction present with impairment of the normal bile flow, with jaundice and cholangitis as common complications. 1H and 31P NMR quantitative analysis of bile specimens from patients with extrahepatic biliary obstruction (n = 80) (with/without jaundice and cholangitis separately and together) was carried out for the chief biliary constituents to determine the relationship between biliary constituents and jaundice (serum bilirubin concentration ≥1.0 mg/dL) and cholangitis (total leucocyte count >11 000 cells/mm3 and/or fever >38.5°C with/without bile culture positivity). Compared with controls (patients without jaundice and cholangitis), median indices of the chief biliary constituents (total bile acids, cholesterol, phosphatidylcholine and inorganic phosphate) were significantly suppressed in patients with cholangitis and/or jaundice. Quantities of total bile acids, cholesterol and phosphatidylcholine correlated negatively with the quantity of bilirubin and with cholangitis, i.e. total leucocyte count. Suppression of biliary constituents correlated significantly with the severity of jaundice and cholangitis. The decrease in biliary constituents in the presence of jaundice and cholangitis is possibly the result of downregulation of the function of transporters located at the canalicular side of hepatocytes, leading to their suppressed indices in bile. This information may have implications in the examination of bile for clinical studies. Copyright © 2008 John Wiley & Sons, Ltd.
An SPH shell formulation for plasticity and fracture analysis in explicit dynamics
Authors: Maurel B. , Combescure A. 
Published: October 2008

AbstractThis paper introduces a new modeling method suitable for the simulation of shell fracture under impact. This method relies on an entirely meshless approach based on the smoothed particle hydrodynamics (SPH) method. The paper also presents the SPH shell formulation being used as well as the different test cases used for its validation. A plasticity model of the global type throughout the thickness is also proposed and validated. Finally, in order to illustrate the capabilities of the method, fracture simulations using a simplified fracture criterion are presented. Copyright © 2008 John Wiley & Sons, Ltd.
A random field model for generating synthetic microstructures of functionally graded materials
Authors: Rahman Sharif 
Published: October 2008

AbstractThis article presents a new level‐cut, inhomogeneous, filtered Poisson random field model for representing two‐phase microstructures of statistically inhomogeneous, functionally graded materials with fully penetrable embedded particles. The model involves an inhomogeneous, filtered Poisson random field comprising a sum of deterministic kernel functions that are scaled by random variables and a cut of the filtered Poisson field above a specified level. The resulting level‐cut field depends on the Poisson intensity, level, kernel functions, random scaling variables, and random rotation matrices. A reconstruction algorithm including model calibration and Monte Carlo simulation is presented for generating samples of two‐phase microstructures of statistically inhomogeneous media. Numerical examples demonstrate that the model developed is capable of producing a wide variety of two‐ and three‐dimensional microstructures of functionally graded composites containing particles of various sizes, shapes, densities, gradations, and orientations. An example involving finite element analyses of random microstructures, leading to statistics of effective properties of functionally graded composites, illustrates the usefulness of the proposed model. Copyright © 2008 John Wiley & Sons, Ltd.
Simultaneous untangling and smoothing of moving grids
Authors: López Ezequiel J. , Nigro Norberto M. , Storti Mario A. 
Published: October 2008

AbstractIn this work, a technique for simultaneous untangling and smoothing of meshes is presented. It is based on an extension of an earlier mesh smoothing strategy developed to solve the computational mesh dynamics stage in fluid–structure interaction problems. In moving grid problems, mesh untangling is necessary when element inversion happens as a result of a moving domain boundary. The smoothing strategy, formerly published by the authors, is defined in terms of the minimization of a functional associated with the mesh distortion by using a geometric indicator of the element quality. This functional becomes discontinuous when an element has null volume, making it impossible to obtain a valid mesh from an invalid one. To circumvent this drawback, the functional proposed is transformed in order to guarantee its continuity for the whole space of nodal coordinates, thus achieving the untangling technique. This regularization depends on one parameter, making the recovery of the original functional possible as this parameter tends to 0. This feature is very important: consequently, it is necessary to regularize the functional in order to make the mesh valid; then, it is advisable to use the original functional to make the smoothing optimal. Finally, the simultaneous untangling and smoothing technique is applied to several test cases, including 2D and 3D meshes with simplicial elements. As an additional example, the application of this technique to a mesh generation case is presented. Copyright © 2008 John Wiley & Sons, Ltd.
Point vortex models of bluff body wakes
Authors: Stremler Mark A. , Brøns Morten 
Published: October 2008

AbstractPeriodic point vortex configurations can be used as reduced‐order models of vorticity‐dominated wakes behind bluff bodies. The staggered Kármán street is considered the canonical representation of these vortex wakes. However, the streamline topology of this configuration is structurally unstable. Slight variations in the intervortex separations cause fluid to wind through the street, which has implications for transport and mixing in vortex wakes. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Finite element differential forms
Authors: Arnold Douglas N. , Falk Richard S. , Winther Ragnar 
Published: October 2008

AbstractA differential form is a field which assigns to each point of a domain an alternating multilinear form on its tangent space. The exterior derivative operation, which maps differential forms to differential forms of the next higher order, unifies the basic first order differential operators of calculus, and is a building block for a great variety of differential equations. When discretizing such differential equations by finite element methods, stable discretization depends on the development of spaces of finite element differential forms. As revealed recently through the finite element exterior calculus, for each order of differential form, there are two natural families of finite element subspaces associated to a simplicial triangulation. In the case of forms of order zero, which are simply functions, these two families reduce to one, which is simply the well‐known family of Lagrange finite element subspaces of the first order Sobolev space. For forms of degree 1 and of degree n − 1 (where n is the space dimension), we obtain two natural families of finite element subspaces, unifying many of the known mixed finite element spaces developed over the last decades. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)