bluuebunny/crossref_metadata_2025_split huggingface dataset:
Kinetics of oxirane cleavage in epoxidized soybean oil
Authors: Zaher F. A. , El‐Mallah M. H. , El‐Hefnawy M. M. 
Published: July 2007

AbstractThe kinetics of oxirane ring cleavage in epoxidized soybean oil have been studied using glacial acetic acid at 60, 70, 80 and 90°C. It was shown that the reaction can be successfully modelled as first order with respect to the epoxide concentration and second order with respect to acetic acid. The reaction velocity constant at 70°C was found to be 2 × 10−3 1−3 hr−1 mol−2, the frequency factor, A, = 2.321 × 107 hr−1 and the energy of activation, Ea = 15.84 k cal mol−1. The effects of the concentration of acetic acid and the temperature on the net yield of epoxides by in situ epoxidation were also studied on the basis of the predicted kinetic parameters of the reaction system.
Inter‐relationships among the properties of fatty oils
Authors: Dutt N. V. K. , Prasad D. H. L. 
Published: July 2007

AbstractProperties of fatty oils, such as viscosity (η), iodine value (IV) and saponification value (SV), are useful in the design of methods and equipments for the processing of the fatty oils to value‐added products. This investigation is aimed at the development of generalized empirical relationships based on a model similar to the Antoine equation for vapor pressure. Two equations resulted. The first equation: log η = [−1.4 + 1.25 (IV/SV)] + [500 − 375 (IV/SV)]/ [(t + 140) − 85 (IV/SV)] relating the logarithm of viscosity to the ratio of iodine value to saponification value (IV/SV) and temperature in degrees centigrade (t), gives an average absolute deviation of 13.0% at 77 data points of several fatty oils. The second equation, somewhat simpler in form: log η = −0.6298 + [273.66/ (t + 88.81)] relating the logarithm of viscosity directly to the temperature in degrees centigrade (t), gives an average absolute deviation of 14.5% at 89 data points of a larger group of fatty oils ranging from almond to tallow.The two equations can be used conveniently to predict either viscosity, iodine value or saponification value, when the other two properties are known, for design purposes.
Hydrogen bromide titration for soaps in fat products
Authors: Zarins Z. M. , White1 J. L. , Feuge1 R. O. 
Published: July 2007

AbstractSince none of the existing methods for determining soaps in fat products have been found to be entirely satisfactory, a method has been devised for the determination of alkali metal soaps by direct titration with Durbetaki reagent (hydrogen bromide dissolved in glacial acetic acid). When the titration was conducted at room temperature in acetic acid‐benzene solution with crystal violet as indicator, soaps of potassium, sodium and lithium could be determined accurately in anhydrous oils, monoglycerides, and sucrose esters. The presence of alcohols, glycerol and sucrose did not interfere in the direct titration. However, oxidized oils, epoxides, and cyclopropenoid acids, which are known to consume hydrogen bromide, did interfere. Products containing the interfering substances could be analyzed by a modified procedure in which the alkali metal cations were extracted from a mixture of amyl acetate andn‐butanol (1:3) into an aqueous solution of acetic acid, and titrated as the acetates.
Maleyl esters of monoglycerides of saturated fatty acids
Authors: Friedman M. , Garti N. 
Published: July 2007

AbstractEsterification between maleic anhydride and monoglycerides of saturated fatty acid has been studied. The nature of reaction vessels, temperature and reaction time have been evaluated in view of the product distribution in the final product. Concentration of monoesters (half‐esters) diesters and dimers has been calculated and related to the reactants’ ratio, time and temperature of the esterification.
Composition of total lipids in rapeseed
Authors: Zaderimowski R. , Sosulski F. 
Published: July 2007

AbstractTotal lipids in medium and low erucic acid cul‐tivars of rapeseed(Brassica napus var. Sinus and Janpol, resp.) were fractionated into polar and non‐polar constituents. Triglycerides, diglycerides, mono‐glycerides, free fatty acids, sterol esters, sterols, phos‐pholipids and glycolipids were quantitated and their fatty acid compositions determined. Triglycerides and phospholipids constituted 92 and 3.4%, resp., of the total lipid from each cultivar. Triglycerides were lower in saturated fatty acids but higher in monoun‐saturated acids and linolenic acid than other lipid fractions. Phospholipids and glycolipids were higher in linoleic acid content than other lipid classes. Generally, the reduction in long chain, monoenoic, fatty acids was associated with a corresponding increase in oleic acid in most low erucic acid frac‐tions.
Conversion of soybean extraction plant in Bolivia to production of flours for human consumption: Feasibility study
Authors: Mustakas G. C. , Milligan E. D. , Taborga A. J. , Fellers D. A. 
Published: July 2007

AbstractDuring an on‐site visit to a commercial soybean crushing plant in Bolivia, two engineers investigated the modifications required to produce a food‐grade soy flour. Differences between processing for human food and for animal feed are described and the various processing stages were evaluated to determine their effects on finished product quality. These stages are: (a) pretreatment of the beans, (b) oil extraction, (c) meal desolventization, and (d) grinding and handling of the flour. Bacteriological control was maintained throughout the plant. The information gained from this study should be useful and directly applicable to other soybean crushing plants in the world.
Determination of dimethylpolysiloxanes in fats and oils
Authors: Doeden W. G. , Kushibab E. M. , Ingala A. C. 
Published: July 2007

AbstractA direct aspiration, flame atomic absorption method has been developed for the determination of dimethylpolysiloxanes (DMPS) in fats and oils. The detection limit of the method is approximately 1 ppm with a standard deviation for samples containing 1–10 ppm DMPS of 0.3. The technique is reasonably rapid, requires a minimum of sample preparation, and is applicable to the analysis of both hydrogenated and nonhydrogenated products.
Sulfur content of crude rapesseed oil from aqueous extraction
Authors: Embong M. S. B. , Jelen P. 
Published: July 2007

AbstractDry heating of rapeseed before grinding increased the sulphur content of the crude rapeseed oil. Boiling the seeds in H2O before grinding caused a slight decrease in the sulphur level of the oil. Control of pH during boiling of the ground rapeseed increased the sulphur content of the oil from ca. 2 ppm at pH 3.1 to ca. 10 ppm at pH 7.6.
Breast‐conserving Therapy for Palpable and Nonpalpable Breast Cancer: Can Surgical Residents Do the Job Irrespective of Experience?
Authors: Cleffken Berry , Postelmans Job , Olde Damink Steven , Nap Marius , Schreutelkamp Ineke , van der Bijl Hans 
Published: July 2007

AbstractBackgroundThe aim of this study was to evaluate the influence of operative experience in obtaining tumor‐free margins in breast‐conserving therapy. In the case of palpable breast cancers, lumpectomies can safely be performed by any surgical resident. For nonpalpable breast cancers, lumpectomies should be treated only by senior residents or attending surgeons, even if supervision during the operation is given by an attending surgeon for junior residents. Radicality of breast carcinoma excision, defined by the tumor‐free margin of the removed specimen has been determined to be the major prognostic factor for local recurrence. The aim of this study was to evaluate the influence of operative experience in obtaining tumor‐free margins in breast‐conserving therapy (BCT). Can lumpectomy for breast carcinoma be performed by surgical residents safely?MethodsAll lumpectomies for breast carcinoma between 1999 and 2003 were included out of a prospective database of a single institution. Radicality of resection and patient and histopathologic tumor characteristics were analyzed for 660 lumpectomies. Operative experience of the surgeon performing the lumpectomy was staged as junior residents (JR, years 1–3 in residency), senior residents (SR; years 4–6 in residency), and attending surgeon (AS).ResultsA significant difference in obtaining tumor‐free margins for palpable tumors was found between ASs (81%) vs. SRs assisted by another resident (92%). For nonpalpable tumors, a significant difference was found in two groups: (1) SRs assisted by another surgical resident (86%) vs. JRs assisted by another surgical resident (61%) and (2) ASs (83%) vs. JRs assisted by another resident (61%) or assisted by an AS (73%).ConclusionSurgical residents can safely perform BCT in patients with palpable breast cancer. The level of experience has no statistical significance for palpable tumors in a high‐volume center. Nonpalpable lesions should be treated only by SRs or ASs.
The pathogenesis and treatment of acid sphingomyelinase‐deficient Niemann–Pick disease
Authors: Schuchman E. H. 
Published: July 2007

SummaryPatients with types A and B Niemann–Pick disease (NPD) have an inherited deficiency of acid sphingomyelinase (ASM) activity. The clinical spectrum of this disorder ranges from the infantile, neurological form that results in death by 3 years of age (type A NPD) to the non‐neurological form (type B NPD) that is compatible with survival into adulthood. Intermediate cases also have been reported, and the disease is best thought of as a single entity with a spectrum of phenotypes. ASM deficiency is panethnic, but appears to be more frequent in individuals of Middle Eastern and North African descent. Current estimates of the disease incidence range from ~0.5 to 1 per 100 000 births. However, these approximations likely under estimate the true frequency of the disorder since they are based solely on cases referred to biochemical testing laboratories for enzymatic confirmation. The gene encoding ASM (SMPD1) has been studied extensively; it resides within an imprinted region on chromosome 11, and is preferentially expressed from the maternal chromosome. Over 100 SMPD1 mutations causing ASM‐deficient NPD have been described, and some useful genotype–phenotype correlations have been made. Based on these findings, DNA‐based carrier screening has been implemented in the Ashkenazi Jewish community. ASM ‘knockout’ mouse models also have been constructed and used to investigate disease pathogenesis and treatment. Based on these studies in the mouse model, an enzyme replacement therapy clinical trial has recently begun in adult patients with non‐neurological ASM‐deficient NPD.
Preparation and Characterization of Nano structured Materials from Fly Ash: A Waste from Thermal Power Stations, by High Energy Ball Milling
Authors: Paul K Thomas , Satpathy SK , Manna I , Chakraborty KK , Nando GB 
Published: July 2007

Abstract
The Class F fly ash has been subjected to high energy ball milling and has been converted into nanostructured material. The nano structured fly ash has been characterized for its particle size by using particle size analyzer, specific surface area with the help of BET surface area apparatus, structure by X-ray diffraction studies and FTIR, SEM and TEM have been used to study particle aggregation and shape of the particles. On ball milling, the particle size got reduced from 60 μm to 148 nm by 405 times and the surface area increased from 0.249 m2/gm to 25.53 m2/gm i.e. by more than 100%. Measurement of surface free energy as well as work of adhesion found that it increased with increased duration of ball milling. The crystallite was reduced from 36.22 nm to 23.01 nm for quartz and from 33.72 nm to 16.38 nm for mullite during ball milling to 60 h. % crystallinity reduced from 35% to 16% during 60 h of ball milling because of destruction of quartz and hematite crystals and the nano structured fly ash is found to be more amorphous. Surface of the nano structured fly ash has become more active as is evident from the FTIR studies. Morphological studies revealed that the surface of the nano structured fly ash is more uneven and rough and shape is irregular, as compared to fresh fly ash which are mostly spherical in shape.
Surface tension of fatty acids and triglycerides
Authors: Chumpitaz Lucy D. A. , Coutinho Lilian F. , Meirelles Antonio J. A. 
Published: July 2007

AbstractSurface tension as a function of temperature was measured for four fatty acids (lauric, myristic, palmitic, and oleic) and two triglycerides (tricaprylin and tripalmitin). These surface tension measurements were performed using a K12 vers. 3.1 (Krüss GmbH) tensiometer at temperatures from 20 (or the melting point of each substance) to 90°C. The constants for a van der Waals‐type correlation as well as for a linear equation are presented. Both equations are quite accurate, presenting mean deviations not exceeding 0.570%. Such correlation constants are valuable in the design or evaluation of processing equipment, especially that involving gas‐liquid contact such as distillation and stripping columns, deodorizers, reactors, and equipment for physical refining.
A Hölder continuous ODE related to traffic flow
Authors: Colombo Rinaldo M. , Marson Andrea 
Published: July 2007

This paper is devoted to the proof of the well posedness of a class of ordinary differential equations (ODEs). The vector field depends on the solution to a scalar conservation law. Forward uniqueness of Filippov solutions is obtained, as well as their Hölder continuous dependence on the initial data of the ODE. Furthermore, we prove the continuous dependence in C0 of the solution to the ODE from the initial data of the conservation law in L1.This problem is motivated by a model of traffic flow.
On composition and absolute-valued algebras
Authors: Mira José Antonio Cuenca 
Published: July 2007

In this note we give a complete description of the composition algebras A over fields of characteristic ≠ 2, 3 in the following cases: if A has an anisotropic norm and x2x = xxx2 for every element; when A has a unitary central idempotent, it satisfies the identity (x2x2)x2 = x2(x2x2), and A is of finite dimension or has anisotropic norm. As a consequence, we obtain the existence, up to an isomorphism, of only seven absolute-valued algebras with a non-zero central idempotent where the last identity holds. This result completes the study of the absolute-valued algebras of this kind that was initiated by El-Mallah and Agawany.We also introduce the class of e-quadratic algebra, which contains the quadratic algebras, but also includes large classes of composition and absolute-valued algebras. Many results on composition, absolute-valued and e-quadratic algebras are shown, and new proofs of some well-known theorems are given.
Ultrastructural changes in the follicular epithelium ofCeratophrys cranwelliprevitellogenic oocytes
Authors: Villecco E.I. , Mónaco M.E. , Sánchez S.S. 
Published: July 2007

SummaryIn this work we carried out ultrastructural, autoradiographic and biochemical analyses of the follicular epithelium duringC. cranwelliprevitellogenesis. This study revealed that the follicular epithelium in early previtellogenesis is constituted of a single layer of squamous homogeneous cells. During mid-previtellogenesis two types of cells develop: dark cells and clear cells. The follicular dark cells are actively involved in the synthesis of RNA, which is transferred to the oocyte through the interface. In late previtellogenesis the dark cells show apoptotic characteristics such as chromatin condensation, DNA fragmentation and cytoplasm shrinkage. This process forms apoptotic bodies that seem to be engulfed by the oocyte. Our results show evidence that, during mid- and lateC. cranwelliprevitellogenesis, the follicular epithelium undergoes remodelling processes interacting with the oocyte.
Molecular characterization of centerin, a germinal centre cell serpin
Authors: Paterson Melinda A. , Horvath Anita J. , Pike Robert N. , Coughlin Paul B. 
Published: July 2007

Centerin [SERPINA9/GCET1 (germinal centre B-cell-expressed transcript 1)] is a serpin (serine protease inhibitor) whose expression is restricted to germinal centre B-cells and lymphoid malignancies with germinal centre B-cell maturation. Expression of centerin, together with bcl-6 and GCET2, constitutes a germinal centre B-cell signature, which is associated with a good prognosis in diffuse large B-cell lymphomas, but the molecular basis for this remains to be elucidated. We report here the cloning, expression and molecular characterization of bacterial recombinant centerin. Biophysical studies demonstrated that centerin was able to undergo the ‘stressed to relaxed’ conformational change which is an absolute requirement for protease inhibitory activity. Kinetic analysis showed that centerin rapidly inhibited the serine protease trypsin (ka=1.9×105 M−1·s−1) and also demonstrated measurable inhibition of thrombin (ka=1.17×103 M−1·s−1) and plasmin (ka=1.92×103 M−1·s−1). Centerin also bound DNA and unfractionated heparin, although there was no functionally significant impact on the rate of inhibition. These results suggest that centerin is likely to function in vivo in the germinal centre as an efficient inhibitor of a trypsin-like protease.
Identification of a novel 82 kDa proMMP-9 species associated with the surface of leukaemic cells: (auto-)catalytic activation and resistance to inhibition by TIMP-1
Authors: Ries Christian , Pitsch Thomas , Mentele Reinhard , Zahler Stefan , Egea Virginia , Nagase Hideaki , Jochum Marianne 
Published: July 2007

MMP-9 (matrix metalloproteinase 9) plays a critical role in tumour progression. Although the biochemical properties of the secreted form of proMMP-9 are well characterized, little is known about the function and activity of cell surface-associated proMMP-9. We purified a novel 82 kDa species of proMMP-9 from the plasma membrane of THP-1 leukaemic cells, which has substantial differences from the secreted 94 kDa proMMP-9. The 82 kDa form was not detected in the medium even upon stimulation with a phorbol ester. It is truncated by nine amino acid residues at its N-terminus, lacks O-linked oligosaccharides present in the 94 kDa proMMP-9, but retains N-linked carbohydrates. Incubation of 94 kDa proMMP-9 with MMP-3 generated the well-known 82 kDa active form, but the 82 kDa proMMP-9 was converted into an active species of 35 kDa, which was also produced by autocatalytic processing in the absence of activating enzymes. The activated 35 kDa MMP-9 efficiently degraded gelatins, native collagen type IV and fibronectin. The enzyme was less sensitive to TIMP-1 (tissue inhibitor of metalloproteinase 1) inhibition with IC50 values of 82 nM compared with 1 nM for the 82 kDa active MMP-9. The synthetic MMP inhibitor GM6001 blocked the activity of both enzymes, with similar IC50 values below 1 nM. The 82 kDa proMMP-9 is also produced in HL-60 and NB4 leukaemic cell lines as well as ex vivo leukaemic blast cells. It is, however, absent from neutrophils and mononuclear cells isolated from peripheral blood of healthy individuals. Thus, the 82 kDa proMMP-9 expressed on the surface of malignant cells may escape inhibition by natural TIMP-1, thereby facilitating cellular invasion in vivo.
Mucosal challenge with cell‐associated or cell‐free feline immunodeficiency virus induces rapid and distinctly different patterns of phenotypic change in the mucosal and systemic immune systems
Authors: Howard Kristina E. , Burkhard Mary Jo 
Published: July 2007

SummaryThe majority of human immunodeficiency virus type 1 (HIV‐1) infections occur via mucosal transmission through contact with genital secretions containing cell‐associated and cell‐free virus. However, few studies have assessed whether exposure to cells, HIV‐1 infected or uninfected, plays a role in the sexual transmission of HIV‐1. This study examined phenotypic changes in mucosal and systemic lymphoid tissue 24 hr after vaginal exposure toin vitroequilibrated infectious doses of cell‐associated or cell‐free feline immunodeficiency virus, uninfected heterologous cells, or medium alone. We found that even at this early time‐point, mucosal exposure to virus induced substantial alterations in the phenotype and distribution of leucocytes, particularly in the tissues of the mucosal immune system. Second, we found that the type of virus inoculum directly influenced the phenotypic changes seen. Vaginal exposure to cell‐free virus tended to induce more generalized phenotypic changes, typically in the peripheral immune system (blood and systemic lymph nodes). In contrast, exposure to cell‐associated virus was primarily associated with phenotypic shifts in the mucosal immune system (gut and mucosal/draining lymph nodes). In addition, we found that exposure to uninfected heterologous cells also induced alterations in the mucosal immune system. These data suggest that significant immune changes occur within the first 24 hr of virus exposure, well before substantial replication would be anticipated. As the mucosal immune system, and particularly the gut, is an early and persistent target for lentiviral replication, these findings have substantial implications for HIV‐1 pathogenesis and vaccine development.
Histone deacetylase inhibitors decrease Toll‐like receptor‐mediated activation of proinflammatory gene expression by impairing transcription factor recruitment
Authors: Bode Konrad A. , Schroder Kate , Hume David A. , Ravasi Timothy , Heeg Klaus , Sweet Matthew J. , Dalpke Alexander H. 
Published: July 2007

SummaryPost‐translational modifications of histone proteins are major mechanisms that modify chromatin structure and regulate gene expression in eukaryotes. Activation of histone acetyltransferases or inhibition of histone deacetylases (HDACs) is generally believed to allow chromatin to assume a more open state, permitting transcriptional activity. We report here the surprising observation that treatment of murine dendritic cells with the HDAC inhibitors trichostatin A (TSA) or suberoylanilide hydroxamic acid (SAHA) in non‐apoptotic concentrations strongly inhibited induction of both interleukin‐12 protein p40 (IL‐12p40) mRNA and protein upon stimulation of Toll‐like receptors (TLRs). Moreover, TLR‐mediated up‐regulation of costimulatory molecules was also inhibited. Up‐regulation of tumour necrosis factor‐α mRNA and protein in response to TLR agonists was only affected upon prolonged exposure to HDAC inhibitors and regulation of IL‐1β was not affected. Similar effects were apparent in murine and human macrophages. Regarding the mode of action, HDAC inhibition increased the acetylation status at the IL‐12p40 locus. Nevertheless, IL‐12p40 chromatin remodelling, binding of Rel‐A and IRF1 to the IL‐12p40 promoter and transcriptional activation were abrogated. In contrast, HDAC inhibitors had no effects on upstream nuclear factor‐κB and mitogen‐activated protein kinase activation. Thus HDACs positively regulate the expression of a subset of cytokine genes by enabling transcription factor recruitment.
Recruitment of mRNAs to cytoplasmic ribonucleoprotein granules in trypanosomes
Authors: Cassola Alejandro , De Gaudenzi Javier G. , Frasch Alberto C. 
Published: July 2007

SummaryTrypanosomes are outstanding examples of the importance of mRNA metabolism in the regulation of gene expression, as these unicellular eukaryotes mostly control protein synthesis by post‐transcriptional mechanisms. Here, we show that mRNA metabolism in these organisms involves recruitment of mRNAs and proteins to microscopically visible ribonucleoprotein granules in the cytoplasm. These structures engage transcripts that are being translated and protect mRNAs from degradation. Analysis of the protein composition of trypanosomal mRNA granules indicated that they contain orthologous proteins to those present in P bodies and stress granules from metazoan organisms. Formation of mRNA granules was observed after carbon‐source deprivation of parasites in axenic culture. More important, mRNA granules are formed naturally in trypanosomes present in the intestinal tract of the insect vector. We suggest that trypanosomes make use of mRNA granules for transient transcript protection as a strategy to cope with periods of starvation that they have to face during their complex life cycles.