bluuebunny/crossref_metadata_2025 huggingface dataset:
Diglycerin und höhere Oligomere des Glycerins als Synthesebausteine
Authors: Jakobson G.
Published: November 2006

In Teil der Arbeit wird über Darstellungsverfahren des Diglycerins und höhere Oligomere des Glycerins berichtet. Erwähnt sind u. a. die Darstellung aus Diallylether, aus Isopropylidenglycerin und Epichlorhydrin und aus Glycidol und Glycerin. Für Polyglycerine allgemein ist die alkalisch katalysierte Kondensation von Glycerin aufgeführt. Für DGLC und PGLC aus Epichlorhydrin sind aus der Produktion der DSW in Rheinberg GC‐Spektren angegeben. In Teil 2 sind Reaktionsprodukte des DGLC aufgeführt, z. B. die Mono‐bis Tetraester der Fettsäuren für Emulgatoren, ein komplizierterer Ester eines Fettsäuregemisches und einer Dicarbonsäure für ein Wollwachssubstitut, ein Veretherungsprodukt mit Epichlorhydrin, Diglykoldialdehyd als Oxidationsprodukt und Diglycerindiformal nach Kondensation mit Formaldehyd. Auf die Möglichkeit zur Herstellung von sog. akalorischen Fettersatzstoffen aus geschütztem (Isopropylidenderivate) oder ungeschütztem Tri‐oder Tetraglycerin wird hingewiesen.
Weitere Erfahrungen mit den DGF‐Empfehlungen zur Beurteilung gebrauchter Brat‐ und Siedefette
Authors: von Zeddelmann H.
Published: November 2006

Es wird zunächst eine Übersicht über die Fettrohstoffe gegeben, die in der Bundesrepublik zur Herstellung von Brat‐ und Siedefetten dienen. Aufgrund ihrer unterschiedlichen Zusammensetzung verhalten sie sich bei längerem Erhitzen unter Fritierbedingungen sehr verschiedenartig. Einige Fette erfahren in relativ kurzer Zeit derartige geschmackliche Veränderungen, daß ihre Verkehrsfähigkeit nicht mehr gegeben ist. Die analytisch ermittelten Werte dagegen bewegen sich absolut innerhalb der erlaubten Grenzwerte. Andere Fettrohstoffe wiederum zeigen genau entgegengesetztes Verhalten. Sensorisch (Geschmack, Geruch, Aussehen) Können sie durchaus noch unauffällig sein, wenn die analytischen Werte eine Verkehrsfähigkeit bereits ausschließen. Von den üblichen Beurteilungskriterien ist der Rauchpunkt aus verschiedenen Gründen nur mit einiger Zurückhaltung verwendbar. Einmal sind trotz verbesserter Untersuchungsmethodik die ermittelten Werte gerade im Grenzbereich des noch Zulässigen von Labor zu Labor sehr unterschiedlich. Darüber hinaus zeigen auch die frischen Ausgangsfette erhebliche Differenzen in ihren Rauchpunkten, was beispielhaft an verschiedenen Raffinaten von Palmölen und gehärteten Erdnußölen gezeigt wird. Deshalb müßte auch die Empfehlung, ein Fett sei nicht mehr verkehrsfähig, wenn die Rauchpunkterniedrigung 50° gegenüber dem frischen Fett überschritten habe, kritisch gesehen werden. Die weiteren Grenzwerte wie 0.7% petrolätherunlösliche oxidierte Fettsäuren sowie‐27% säulenchromatographisch bestimmter polarer Anteile haben sich durchaus bewährt. Dabei verdient die Bestimmung der polaren Anteile wegen der einfachen Arbeitsweise, der schnelleren Durchführung und der geringeren Fehlerbreite den Vorzug. Zur Betriebskontrolle und zur Vorauswahl verdächtiger Fette hat der “Fritest” als Schnellmethode weiter an Beliebtheit gewonnen, da er einfach zu handhaben ist und Ergebnisse mit ausreichender Zuverlässigkeit liefert.
Pulsed NMR Method for Solid Fat Content Determination in Tempering Fats Part II: Cocoa Butters and Equivalents in Blends with Milk Fat
Authors: Petersson B.
Published: November 2006

Earlier, in part I of this paper, a method for Solid Fat Content (SFC) determination with pulsed NMR has been described for cocoa butters and cocoa butter equivalents. The present work (part II) is a continuation with these fats together with 10 to 30% milk fat. These fat blends need a modified pretreatment before NMR analysis. Crystallisation of the melted fat should be done at 0° C for 150 min and subsequent tempering performed at 19.0° C for 40 h. No other deviations from the earlier reported method have been carried out. Also SFC determination for chocolate has been described and used as a tool for the development of a proper NMR method, giving SFC on a pure fat blend more or less equal to SFC in corresponding milk chocolate. Different pretreatments (i.e. tempering temperatures) have given very different SFC results. A crystallographic understanding of these were achieved using X‐ray, microscope and thermal analysis techniques. The chosen tempering temperature 19.0° C gave a single solid solution, which is essential in chocolate if the right properties of the fat are to be reached. Differences in SFC on pure fat blends by different tempering temperatures could, in the same way, be found in milk chocolates stored at corresponding temperatures. Storage temperature can, to a certain degree, be chosen in order to optimize and control the SFC (i.e. properties) in a chocolate product. The choice of initial temperature especially will strongly influence the SFC in chocolate and the crystal lattice remains virtually unaffected by changes in storage temperature.
Studies on Leguminous Seeds III
Authors: Chowdhury A. R. , Banerji R. , Tiwari S. R. , Misra G. , Nigam S. K.
Published: November 2006

The seeds of 20 plant species belonging to Papilionaceae were studied for their fatty acid and mineral compositions. The fat and protein contents ranged from 2–30% and 21–45% respectively. The seed oils were found rich in C‐18 unsaturated acid (40.5–77.2%).
Herbicidal Effect on Soybean Oil
Authors: Farag R. S. , M. Abdel‐Magid M. , Abo‐Raya S. H. , Salim A. A.
Published: November 2006

Influence of some herbicides as single applications or mixtures for controlling weeds in soybeans was studied. The most important physical and chemical properties of soybean oil were determined. Gas‐liquid chromatographic analysis was employed for the qualitative and quantitative determination of fatty acid composition of oils produced from untreated and treated plants. The results demonstrated that saponification and iodine values were remarkably changed and the extent of the change was highly dependent upon the herbicidal type. The fatty acid composition of soybean oil was obviously altered by herbicide applications. The soybean oils produced under the influence of different herbicides varied in their degree of unsaturation and can be used for human and industrial purposes.
Kolonnenauslegung zur physikalischen Raffination von Ölen ‐ Theorie und Praxis
Authors: Shadiakhy A.
Published: November 2006

Für die thermodynamische Auslegung der destillativen Entsäuerung von Fetten und Ölen werden oft wegen mangelnder Phasenausgleichsdaten Vereinfachungen benutzt, die das tatsächliche Verhalten solcher Systeme bei der Destillation nicht richtig beschreiben. Seit mehr als drei Jahren wurden in unserer Pilot‐Anlage für physikalische Raffination und Desodorierung Versuche durchgeführt. Parallel zu diesen Versuchen wurden Computer‐Simulationen unter Verwendung verschiedener Ansätze für die Aktivitätskoeffizienten durchgeführt. Anhand einiger Beispiele werden die Resultate der theoretischen Berechnungen mit den gemessenen Werten verglichen.
Studies on Minor Seed Oils VI
Authors: Mukarram M. , Ahmad I. , Farooqi Javed A.
Published: November 2006

Seeds from five species fo various plant families have been analyzed for their oil contents and physico‐chemical characteristics with the help of spectroscopic (UV, IR) and chromatographic (TLC‐GLC) techniques. Out of the five seed oils examined here, only two oils, Ipomea cardiophylla and Echinochloa colona, were found to have good combined oleic‐linoleic contents (> 60%). Lepidagathis trinervis was interestingly noted for high content of oleic acid (72%).
Characterization of Amaranthus hybridus Phospholipids
Authors: Batra Anita , Mehta B. K. , Bokadia M. M.
Published: November 2006

The seeds of Amaranthus hybridus contain about 0.66 percent phospholipids. Silica gel column chromatography and analysis of eluates as such and after acid hydrolysis using paper and thin layer chromatographic techniques have shown that the major constituents of A. hybridus seed phospholipids are phosphatidyl ethanolamine, phosphatidyl choline and phosphatidyl inositol. The other two identified components present in small amount are sphingomyelin and lysolecithin.
Palm Oil Products ‐ Why and How to Use them
Authors: Berger K. G.
Published: November 2006

Palm oil is a very versatile oil. Its techno‐economic strength is based on the following factors: 1. It is often cheaper than soyabean oil; 2. it can be used as a major component of consistent or solid fats without hydrogenation; 3. Malaysian refined palm oil requires only little reprocessing before use; 4. Palm oil possesses specific properties of value. It imparts Beta prime crystallinity on blends. It has great stability at frying temperatures. It contains no trans double bonds. A palm mid‐fraction is highly compatible with cocoabutter. A number of specific food applications and formulae are discussed. Soap is the largest technical use of fats. Palm stearin is competitive with tallow in price, and may offer cost savings because it requires less clean‐up for soap manufacture.
Temperaturmeßumformer in Warten‐ oder Feldausführung
Authors: Keuthen K.
Published: November 2006

Temperaturmessungen können mit Meßumformern MU in Warten‐ oder Feldausführung realisiert werden. Unter Feldumformem werden Zweileitermeßumformer verstanden, welche in zwei unterschiedlichen Montageformen angeboten werden: 1. Meßumformer integriert im Anschlußkopf der Schutzarmatur ‐ Kopfumformer MU (K); 2. Meßumformer im separat montierten Feldgehäuse MU (FG). Wartenmeßumformer MU (W) sind Geräte, welche an einem geschützten Einsatzort betrieben werden. Die Montage der MU (W) kann in 19″ ‐Technik, Wandmontage oder in Einzelgehäusen erfolgen. Alle Wartenmeßumformer sind jedoch in 4‐Leitertechnik, d. h. mit separater Hilfsenergiezuführung realisiert. Bei der Diskussion um die Vor‐ oder Nachteile der beiden Montagemöglichkeiten kommen die verschiedensten Argumente zum Tragen. Die Wertigkeit der Einzelargumente kann von Anwendung zu Anwendung unterschiedlich sein, jedoch erscheint es wichtig, einen Überblick über die Argumente zur besseren Entscheidungsfindung zur Verfügung zu haben. Im folgenden ist deshalb der Versuch unternommen, einen möglichst vollständigen Überblick zu erstellen.
Changes in Triglyceride Composition and Melting Properties of Butter Fat Solid Fraction/Rapeseed Oil Mixtures Induced by Lipase Catalysed Inter‐esterification
Authors: Kalo P. , Vaara K. , Antila M.
Published: November 2006

Butter fat solid fraction/rapeseed oil mixtures were interesterified in the presence of Candida cylindracea lipase as catalyst. The changes in the triglyceride composition were followed through quantitative determination of triglycerides with different acyl carbon number and level of unsaturation by high resolution gas chromatography. The inter‐esterification decreased the proportions of trisaturated triglycerides and increased those of monoene triglycerides in the acyl carbon number range 44‐52. The triglyceride compositions of reaction products were similar to the triglyceride composition calculated according to random distribution. The melting and crystallisation properties of the reaction products were determined by DSC method. The melting curves of reaction products showed narrower melting ranges than untreated mixtures, and lower proportions of fat melting at high temperature range.
Die Aflatoxinbeseitigung in Futter‐ und Nahrungsmitteln ‐Eine Bestandsaufnahme und Vorstellung eines neuen Verfahrens
Authors: Münch E.‐W. , Stein W.
Published: November 2006

Mykotoxine, insbesondere die Aflatoxine, sind in immer stärkerem Maße zu einem Problem der Nahrungs‐ und Futtermittel geworden. Bis heute ist es nicht gelungen, die Verbreitung einzudämmen. Eine Reihe von Umweltfaktoren begünstigen die Aflatoxinbildung. Hohe Lufttemperaturen und ‐feuchtigkeiten sind besonders zu nennen. Detoxifikationsmethoden sind: 1. Physikalische Verfahren wie mechanisches Trennen, Bestrahlung, Trocknen, Extrahieren u. a.; 2. Chemische Verfahren unter Verwendung von Alkalien bzw. Säure. Ein erfolgreiches Verfahren sollte das Aflatoxin detoxifizieren, die Rekontamination erschweren und Pilz unschädlich machen. Versuche mit hochgespannten Kondensatorentladungen zur Lösung des Problems wurden durchgeführt. Ergebnisse, die mit einer Pilotanlage erzielt wurden, zeigen, daß mit diesem physikalischen Verfahren eine Lösung gegeben ist. Das Verfahren eignet sich sowohl für große als auch für kleine Leistungen. Die vorgestellte Anlagenkonzeption wird im Hinblick auf Investitions‐ und Betriebskosten hin untersucht.
Fraktionierung mehrfach ungesättigter Fettsäuren aus verschiedenen natürlichen Rohstoffen
Authors: Traitler H. , Wille H. J. , Studer A.
Published: November 2006

Die Samenöle der schwarzen Johannisbeere, des Borretschs und der Nachtkerze sind bekannte Rohstoffe für γ‐Linolensäure (GLA) mit Konzentrationen bis zu 25% für Borretschöl. Derartige GLA‐Gehalte sind für die meisten Anwendungen dieser Öle ausreichend. In speziellen Fällen werden höhere Konzentrationen bis zu 70% GLA oder mehr benötigt. GLA läßt sich aus diesen Rohstoffen weder durch Destillation noch durch fraktionierte Kristallisation anreichern. Die Trennung von Fettsäuren mittels präparativer Hochleistungs‐Flüssigkeits‐Chromatographie gelingt nur auf Reversed‐Phase‐Kolonnen des RP‐18‐Typs. Eine spezifische Anreicherung von γ‐Linolensäure ist jedoch durch Fraktionierung von Fettsäuren mit Harnstoff möglich, auch von Fettsäuren des schwarzen Johannisbeerkernöls, das neben 15‐20% GLA noch bis zu 14% α‐Linolensäure enthält. Bei Anwendung dieses Verfahrens in einer Pilot‐Anlage konnte, ausgehend von schwarzem Johannisbeerkernöl, ein 70 bis 80% iges γ‐Linolensäurekonzentrat erhalten werden, wobei je nach Größe der Anlage auch eine 2‐Stufen‐Fraktionierung vorzusehen ist.
Chemical Evaluation of Rapeseed
Authors: Farag R. S. , Hallabo S. A. S. , Hewedi F. M. , Basyony A. E.
Published: November 2006

The seed chemical composition and oil physical and chemical constants of two imported rapeseed German varieties and one locally produced in Egypt were studied. Rapeseeds are characterized by high lipid and protein contents. The fatty acid analysis indicated that palmitic and oleic acids were the most prevalent saturated and unsaturated acids, respectively. Also, the rapeseed oils under study were free from long‐chain fatty acids (>C18). The unsaponifiables were fractionated by GLC into 36 different compounds of which 26 hydrocarbons were identified. The hydrocarbons having carbon atoms between C20 and C24 represent the most common compounds. Campesterol, stigmasterol and β‐sitosterol were present in appreciable amounts in German varieties while these compounds occurred as trace substances in the seeds produced in Egypt.
Der Einfluß von Emulgatoren auf das Verhalten von Fett im Eismix während des Reifens
Authors: Kielmeyer F. , Schuster G.
Published: November 2006

Das Reifen von Eismix nimmt im Herstellungsprozeß von Eiskrem die längste Zeit in Anspruch. Hier erfolgt unter anderem die Fettkristallisation, die für die eigentliche Eisherstellung im Freezer von Bedeutung ist. Anhand von einfachen, anwendungstechnischen Untersuchungsmethoden wird der Einfluß der für die Speiseeisherstellung gebräuchlichsten Emulgatoren in Abhängigkeit von ihrem Sättigungsgrad und ihrer Hydrophilie auf die Entstehung von freiem extrahierbarem Fett und der Emulsionsstabilität untersucht. Gesättigte Emulgatoren zeigen über die Reifezeit keine Veränderung des extrahierbaren Fettes und eine stabile Emulsion. Mit ungesättigten Emulgatoren ergibt sich eine Zunahme des extrahierbaren Fettes und eine Verschlechterung der Emulsionsstabilität. Diese Veränderungen sind besonders deutlich in den ersten 3 bis 6 Stunden der Reifezeit. Die endgültige Orientierung der Protein‐Emulgator‐Membran um die Fetteilchen ist erst nach 12 bis 24 Stunden Reifezeit abgeschlossen. Dies könnte erklären, daß in der Praxis 3 Stunden Reifezeit als unbedingt notwendig angesehen werden, eine längere Reifezeit jedoch eine weitere Verbesserung der Eiskremqualität bewirkt.
Über den Einfluß des kolloichemischen Aufbaus von Trägergrundlagen auf die cutane Aufnahme eines Pharmakons. I. Entwicklung von potentiellen Transportsystemen auf der Basis von Kohlenwasserstoff als Ölkomponente
Authors: Ziegenmeyer J.
Published: November 2006

Dieser Teil beschäftigt sich mit der Entwicklung und kolloidchemischen Differenzierung einer Reihe von Modellsystemen aus Öl (Dodecan), Wasser und nichtionischem Tensid (Polyoxyäthylen(7)‐Lauryläther). Kombinationen aus Wasser und Tensid liefern in bestimmten Mischungsverhältnissen stabile Lösungen, micellar oder invers‐micellar aufgebaut sowie zwei mesomorphe Phasen, ein Gel mit Hexagonalstruktur (M) und ein Bereich mit lamellarem Schichtgitter (N). Kommt Dodecan als dritte Komponente hinzu, wird es in die unpolaren Zonen der verschiedenen Strukturen eingebaut und vergrößert im Falle der M‐Phase den Röhrendurchmesser, im Falle der N‐Phase die Dicke der Lipiddoppelschicht. Die Bildung von Emulsionen, Cremes und einer weiteren Gelphase hängt eindeutig von der Anwesenheit der Ölkomponente ab. Ihre unterschiedlichen Strukturen werden beschrieben, wobei im Falle der Creme ihr spezifischer, von dem Aufbau der Emulsion differierender, dreiphasiger Aufbau herausgestellt und im Falle des optisch isotropen, viscoelastischen Gels ein kubisches Gitter angenommen wird.
Chromatographische Methoden bei der Untersuchung von Fritierfetten
Authors: Gertz Ch
Published: November 2006

Bei der Untersuchung von 125 Proben Fritierfett und ‐61 wurden verschiedene chromatographische Methoden (Gaschromatographie, Gelpermeationschromatographie, Säulenchromatographie) angewandt. Die Ergebnisse wurden mit dem Gehalt an in Petrolether unlöslichen oxidierten Fettsäuren (OXF) verglichen. Danach entsprachen 0.7% OXF einem Gehalt an polaren Anteilen von 24.7%. Die Bestimmung der monomeren Glyceride erfolgte mittels Gelpermeationschromatographie (GPC) an einem druckstabilen Styrol‐Divinyl‐Copolymer (PL‐Gel). Da bei der GPC keine Differenzierung zwischen nichtoxidierten und oxidierten monomeren Glyceriden erfolgt, wurde parallel der Gehalt der Fritierfette an monomeren nichtoxidierten Fettsäuren gaschromatographisch be‐stimmt, um den Anteil an unveränderten monomeren Tri‐ und Di‐glyceriden zu errechnen. In Fritierfetten mit einem Gehalt von mehr als 0.7% OXF waren weniger als 86.7% monomere Tri‐ und Diglyceride und weniger als 71.6% monomere nichtoxidierte Tri‐und Diglyceride.
Zur biologischen Wirksamkeit von Vitamin E
Authors: Wallat S.
Published: November 2006

Vitamin E ist der übergeordnete Begriff ür alle biologisch aktiven Tocopherole und Tocotrienole. Meist wird das natürlich vorkommende D‐alpha‐Tocopherol unter Vitamin E verstanden. Natürliche und synthetische Tocopherole weisen im Hinblick auf ihre biologische Wirksamkeit erhebliche Unterschiede auf. Die Betrachtung der Tocopherolgehalte menschlicher Gewebe und Zellen verdeutlicht die physiologische Bedeutung des freien RRR‐alpha‐Tocopherols gegenüber anderen Tocopherolen und seinen Derivaten. Der Mensch deckt den Vitamin‐E‐Bedarf durch bevorzugte Verwertung des D‐alpha‐Tocopherols seiner Nahrung. Dessen relativ größte biologische Wirksamkeit ist in einer Vielzahl relevanter Modelle sowie in klinischen Studien abgesichert. Die Überlegenheit des einzigen natürlichen Isomeren, des RRR‐oder D‐alpha‐Tocopherols, beim Menschen wird dargelegt.
Sonchus oleraceus Seed Oil‐Characterization of HBr‐Reactive Oxygenated Acid
Authors: Ahmad R. , Ahmad I. , Ahmad F. , Osman S. M.
Published: November 2006

Seed oil of Sonchus oleraceus (Compositae) contains cis‐12, 13‐epoxyoctadec‐cis‐9‐enoic acid (Vernolic, 13.7%). Structural details of this HBr‐reactive acid are obtained through comparative chromatographic, spectral and chemical data with those of pure vernolic acid isolated from Vernonia anthelmintica seed oil. GLC analysis of the esters of S. oleraceus also showed a C14:1 acid (1.6%).
Smoking‐responsive juvenile‐onset Parkinsonism
Authors: Hanagasi Hasmet Ayhan , Lees Andrew , Johnson Janel O. , Singleton Andrew , Emre Murat
Published: November 2006

We describe a patient with juvenile levodopa‐responsive Parkinsonism who reported a dramatic response to cigarette smoking with transient but marked improvement of motor symptoms associated with oculogyric crises and psychotic behavior. His beta‐CIT single‐photon emission computed tomography scan showed a complete absence of presynaptic dopaminergic nerve terminals. © 2006 Movement Disorder Society
Quantitative Analysis of In Vivo Cell Proliferation
Authors: Cameron Heather A.
Published: November 2006

Injection and immunohistochemical detection of 5‐bromo‐2′‐deoxyuridine (BrdU) has become the standard method for studying the birth and survival of neurons, glia, and other cell types in the nervous system. BrdU, a thymidine analog, becomes stably incorporated into DNA during the S‐phase of mitosis. Because DNA containing BrdU can be specifically recognized by antibodies, this method allows dividing cells to be marked at any given time and then identified at time points from a few minutes to several years later. BrdU immunohistochemistry is suitable for cell counting to examine the regulation of cell proliferation and cell fate. It can be combined with labeling by other antibodies, allowing confocal analysis of cell phenotype or expression of other proteins. The potential for nonspecific labeling and toxicity are discussed. Although BrdU immunohistochemistry has almost completely replaced tritiated thymidine autoradiography for labeling dividing cells, this method and situations in which it is still useful are also described.
A statistical comparison of pad numbers versus pad weights in the quantification of urinary incontinence
Authors: Dylewski Drew A. , Jamison Margaret G. , Borawski Kristy M. , Sherman Neil D. , Amundsen Cindy L. , Webster George D.
Published: November 2006

Aims

Pad per day (PPD) usage is a frequently utilized measure of urinary incontinence. The 24‐hour pad weight test (24PWT) is a reproducible test for quantifying incontinence volumes. We investigated whether PPD validly reports the magnitude of urinary incontinence.

Methods

This was a retrospective review of patients undergoing stress incontinence surgery from July 2002 to 2005. Inclusion criteria were a documented 24PWT and patient‐reported PPD usage. Grams of urine loss per pad (GPP) provided a third measure of incontinence. Descriptive statistics and correlations between all variables and significance were noted. Factor analysis was performed on the three measures of leakage and age for all patients over age 50.

Results

One hundred forty‐five male and 116 female patients met inclusion criteria. Correlated against 24PWT, GPP has the strongest association with a correlation of 0.80 for males and 0.88 for females. PPD has a weaker correlation of 0.64 for males and 0.61 for females (R2 = 0.38 overall). Factor analysis identified two components associated with incontinence. A “leakage” component correlated best with 24PWT and GPP. Additionally, an “age” component implies that despite stable 24PWT values, older patients increase GPP while PPD decreases.

Conclusions

Self‐reported PPD is an unreliable measure of incontinence as this variable only measures 38% of the variation of urinary incontinence volume. Patients at a given PPD level present with a wide range of 24PWT values. Older patients have higher per‐pad leakage. Future incontinence studies should report 24PWT to ensure the most reliable and uniform data. Neurourol. Urodynam. © 2006 Wiley‐Liss, Inc.
Statistical and conformational analysis of the electron density of protein side chains
Authors: Shapovalov Maxim V. , Dunbrack Roland L.
Published: November 2006

Protein side chains make most of the specific contacts between proteins and other molecules, and their conformational properties have been studied for many years. These properties have been analyzed primarily in the form of rotamer libraries, which cluster the observed conformations into groups and provide frequencies and average dihedral angles for these groups. In recent years, these libraries have improved with higher resolution structures and using various criteria such as high thermal factors to eliminate side chains that may be misplaced within the crystallographic model coordinates. Many of these side chains have highly non‐rotameric dihedral angles. The origin of side chains with high B‐factors and/or with non‐rotameric dihedral angles is of interest in the determination of protein structures and in assessing the prediction of side chain conformations. In this paper, using a statistical analysis of the electron density of a large set of proteins, it is shown that: (1) most non‐rotameric side chains have low electron density compared to rotameric side chains; (2) up to 15% of χ1 non‐rotameric side chains in PDB models can clearly be fit to density at a single rotameric conformation and in some cases multiple rotameric conformations; (3) a further 47% of non‐rotameric side chains have highly dispersed electron density, indicating potentially interconverting rotameric conformations; (4) the entropy of these side chains is close to that of side chains annotated as having more than one χ1 rotamer in the crystallographic model; (5) many rotameric side chains with high entropy clearly show multiple conformations that are not annotated in the crystallographic model. These results indicate that modeling of side chains alternating between rotamers in the electron density is important and needs further improvement, both in structure determination and in structure prediction. Proteins 2007. © 2006 Wiley‐Liss, Inc.
Insight into the catalytic mechanism of arginine deiminase: Functional studies on the crucial sites
Authors: Wei Yunzhou , Zhou Hao , Sun Yi , He Yingbo , Luo Yongzhang
Published: November 2006

Arginine deiminase (ADI) catalyzes the irreversible hydrolysis of arginine to citrulline and ammonia. It belongs to a newly classified superfamily of guanidino‐group‐modifying enzymes. Located in the catalytic center of Mycoplasma hominis ADI, some crucial sites (Asp160, Glu212, His268, and Asp270) are highly conserved among these enzymes. Here, we constructed five ADI single mutants D160E, E212D, H268F, H268Y, and D270E, and three double mutants D160E/D270E, D160E/E212D, and E212D/D270E, aiming to evaluate the contributions of these crucial residues to the structure, stability, and enzymatic activity of ADI, and to elucidate their roles in the catalytic process of this family of enzymes. Tryptophan emission fluorescence and circular dichroism were used to analyze the different effects of mutagenesis on these conserved residues on the secondary and tertiary structures of ADI. Urea‐induced unfolding and trypsin digestion were applied to measure their stabilities against denaturants and proteases, respectively. Additionally, the enzymatic activities of ADI and its mutants were measured. Here, we report that all the mutations have little effect on the native structure of ADI. However, the substitutions on these crucial sites still interfere with the stability of ADI to different degrees. As these mutations impair both the substrate binding and the substrate induced conformational changes of ADI to different extents, most of the mutants except D160E (preserves about 30% of the enzymatic activity of wild type) have totally lost the enzymatic activity in the hydrolysis of arginine and the inhibitory ability on the proliferation of mouse melanoma cells. Proteins 2007. © 2006 Wiley‐Liss, Inc.
Test protocol for simulating truck and rail vibration and rail impacts in shipments of automotive engine racks
Authors: Singh S. Paul , Burgess Gary J. , Rojnuckarin Paween
Published: November 2006

A study of the truck and rail transport environments using racks containing Ford engines was conducted to quantify shock and vibration levels during shipment. Tri‐axial acceleration data was collected at several locations on the floor of the vehicles and on the racks themselves to determine the severity of shock and vibration input from truck trailers and rail boxcars. Power Spectral Density plots were developed from the data collected and used to simulate truck and rail shipments on an electro‐hydraulic vibration table. The results showed that the highest vibration levels in the steel racks occurred at 4 Hz in the vertical direction for truck shipments, and between 12–16 Hz for rail shipments. The vibration levels in the longitudinal and lateral directions were much lower than in the vertical direction for truck shipments. The most severe shock to a rack in rail shipments was 5.7 G peak in the longitudinal direction as a result of coupling.
Sol‐gel zirconia coating capillary microextraction on‐line hyphenated with inductively coupled plasma mass spectrometry for the determination of Cr, Cu, Cd and Pb in biological samples
Authors: Wu Yiwei , Hu Bin , Jiang Zucheng , Feng Yuqi , Lu Peng , Li Boyangzi
Published: November 2006

A sol‐gel zirconia coating was developed for the preconcentration/separation of trace Cr, Cu, Cd and Pb by capillary microextraction, and the adsorbed analytes were on‐line eluted for detection using inductively coupled plasma mass spectrometry (ICP‐MS). By immobilizing sol‐gel zirconia on the inner surface of a fused‐silica capillary, the sol‐gel zirconia coating was simply prepared. Its adsorption properties, stability and the factors affecting the adsorption behaviors of Cr, Cu, Cd and Pb were investigated in detail. In the pH range from 7.8 to 10, the zirconia‐coated capillary (35 cm × 0.15 mm) is selective towards Cr, Cu, Cd and Pb, and the analyzed ions could be desorbed quantitatively with 0.2 mL of 0.5 mol/L HNO3 at a rate of 0.2 mL/min. With a consumption of 1.25 mL sample solution, an enrichment factor of 6.25, and detection limits (3σ) of 9.9 pg/mL Cr, 17.9 pg/mL Cu, 4.5 pg/mL Cd and 3.7 pg/mL Pb were obtained. The precisions for nine replicate measurements of 1 ng/mL Cr, Cu, Cd and Pb were 4.9% Cr, 2.2% Cu, 2.0% Cd and 3.2% Pb (RSD), respectively. The proposed procedure has been applied to the determination of Cr, Cu, Cd and Pb in human urine, which was subjected to microwave‐assisted digestion prior to analysis, and the recoveries for these elements were 89.2–101.8%. In order to validate the developed procedure, a NIES No.10‐a Rice Flour‐Unpolished certified reference material and a BCR No. 184 Bovine Muscle certified reference material were analyzed, and the results are in good agreement with the certified values. Copyright © 2006 John Wiley & Sons, Ltd.
Über das Verhalten von Stärkesirupsäften beim Einkochen und bei Aktivkohlebehandlung unter Betriebsbedingungen
Authors: Hönsch W. , Kröner W.
Published: November 2006

Vorwort: Vorliegende Arbeit wurde Ende 1944 im Betriebslabor der Central‐Genossenschafts‐Stärkefabrik, e.G.m.b.H., Schneidemühl, in Gemeinschaft mit dem Forschungsinstitut für Stärkefabrikation in Berlin fertiggestellt. Es sollte dies der Beginn einer eingehenden Untersuchung aller Einflüsse sein, denen der Stärkesirupsaft im Betrieb ausgesetzt ist. Der Krieg und der Zusammenbruch haben die Ausführung dieses Planes zunichte gemacht. Wenn ich als einer der wenigen Überlebenden unserer Arbeitsgemeinschaft, die sich aus Laboranten, Meister und Arbeitern zusammensetzte, diese Arbeit heute nach 5 Jahren zur Veröffentlichung bringe, so geschieht das in Erinnerung an die verstorbenen und verschollenen Mitarbeiter. Eine abschließende Stellungnahme zur Frage der Entfärbungsmittel behalte ich mir vor.
Erfahrungen mit der Auswaschung von Kartoffelreibsel ohne Wasserzusatz
Authors: Bode Heinrich F. W.
Published: November 2006

Experience in Potato Pulp Washing without Water Addition. In order to reduce the quantity of waste water from potato starch factories many have tried to keep the amount of water, required for washing out the starch from the pulp as low as possible. Our process is based on utilization of the water contained in the potatoes (approx. 80%, including soluble components) for starch extraction, in such a way that undiluted fruit water is separated and further treatment can be carried out in a comparatively economical way.

Most of today's starch factories are tied up with production methods that make it impossible to utilize the water contained in the potatoes, as there is firstly no possibility of recirculating the fruit water and secondly there are foaming problems causing a negative effect on the efficiency.

A continuous process guaranteeing a direct flow, excluding accumulation of foam, was installed and tested in both a Swedish and in a Dutch factory. The experience obtained showed that starch extraction with fruit water has no negative influence on the efficiency of the extraction (approx. 1 % free starch in the pulp DS/DS) and that up to 80% of the fruit water could be removed in a concentrated form. By extending the extraction process, and by using 300 l of process water from the refining section per ton of potatoes, separation of the fruit water can be increased up to 97%.
Factors Affecting the Catalytic Hydrogenation of D‐Glucose Part II. Effect of Pressure and Temperature
Authors: Abdel Akher M. , Ghali J. , Raouf M. S. , Roushdi M.
Published: November 2006

The effect of different degrees of pressure and temperature on the rate of the catalytic hydrogenation of glucose has been investigated.
A sensitive and reliable quantification method for mouse interleukin‐12 p70 based on fluorometric sandwich ELISA (FS‐ELISA)
Authors: Nakamura Tadashi , Kimura Hirokazu , Kato Masahiko , Kurashige Satonori , Wakamatsu Kaori
Published: October 2006

Interleukin‐12 (IL‐12) p70 is an important cytokine secreted by antigen‐presenting cells in response to antigenic stimulation; it is a heterodimer of p35 and p40 subunits. Here, we report a new, highly sensitive, and reliable method that employs fluorometric sandwich ELISA for quantification of the mouse IL‐12 (moIL‐12) p70 protein. Our method could quantify moIL‐12 p70 in the range of approximately 0.5 to 500 pg/ml. In the assay, no signals were produced by the moIL‐12 p40 monomer, homodimer [(p40)2], or mouse IL‐23 even up to a concentration of 500 pg/ml; this ensures that our assay has a high specificity for moIL‐12 p70. To demonstrate that our method can determine natural moIL‐12 in real physiological/pathological samples, we monitored the moIL‐12 p70 secretion from peritoneal exudative cells after lipopolysaccharide (LPS) stimulation. IL‐12 p70 secretion as early as 3 h after LPS stimulation was reliably detected due to the high sensitivity of the method.
Protein dolichylation in Plasmodium falciparum
Authors: D'Alexandri Fabio Luiz , Kimura Emilia Akemi , Peres Valnice Jesus , Katzin Alejandro Miguel
Published: November 2006

We performed reverse‐phase thin‐layer chromatography and reverse‐phase high‐performance liquid chromatography (RP‐HPLC) analysis of polyisoprenoids released by sulfonium‐salt cleavage with methyl iodide from Plasmodium falciparum proteins labeled with [3H]FPP or [3H]GGPP and showed that a dolichol of 11 isoprene units is bound to 21–28‐kDa protein clusters from trophozoite and schizont stages. The dolichol structure was confirmed by electrospray‐ionization mass spectrometry analysis. Treatment with protein synthesis inhibitors and RP‐HPLC analysis of the proteolytic digestion products from parasite proteins labeled with [35S]cysteine and [3H]FPP showed that the attachment of dolichol to protein is a post‐translational event and probably occurs via a covalent bond to cysteine residues.
Black Laborers, the Republican Party, and the Crisis of Reconstruction in Lowcountry South Carolina
Authors: Kelly Brian
Published: November 2006

The wave of strikes that swept across the South Carolina rice fields in late 1876 offer rich material for revisiting the most compelling issues in the postwar Reconstruction of the US's former slave states. They expose sharp tensions between the Republican Party's black, working-class constituency and its mostly white, bourgeois leadership. Recent studies, based almost entirely on Northern published opinion, have made the case that Northern Republican elites were driven to “abandon the mid-century vision of an egalitarian free labor society” by assertive ex-slaves oblivious to the “mutual interests” that ostensibly bound them and their employers. This article, based on extensive archival research, asserts that similar fissures opened up between freedpeople and southern Republican officials. In a series of highly effective mobilizations against local planters and determined attempts to block party officials from betraying their interests, rice fieldhands demonstrated a clear understanding of the critical issues at stake during the months leading up to the collapse of Reconstruction. Their intervention contrasted not only with the feeble holding operation pursued by moderates in the upper levels of the Republican party, but also with the timidity of many locally rooted black officials nearer to the grassroots.
The Late Romance of the Soviet Worker in Western Historiography
Authors: Siegelbaum Lewis H.
Published: November 2006

This essay is animated by a single, seemingly simple, question: “What has happened to Soviet labor and working-class history?” The obvious answer is that it went the way of the Soviet working class. But to attribute changing scholarly interests or emphases to recent or contemporary Russian politics is too simplistic. It ignores too many other factors that impinge on why and how we study what we do. While the near disappearance of class from post-Soviet discourse certainly has had an impact on Western historians, I would suggest that both broader and narrower trends have been at work shaping our scholarly agendas. In 1990, just as the Soviet Union was in its last throes, Leo van Rossum published in this very journal an outstanding omni-review of “Western Studies of Soviet Labour during the Thirties”. A few years further on, “in the cold light of the post-Soviet dawn”, Ron Suny and I searched Soviet history for its working class. It is time once again to revisit this terrain.
Image-guided surgical microscope with mounted minitracker
Authors: Caversaccio M , Garcia-Giraldez J , Gonzalez-Ballester M , Marti G
Published: November 2006

A new image-guided microscope using augmented reality overlays has been developed. Unlike other systems, the novelty of our design consists in mounting a precise mini and low-cost tracker directly on the microscope to track the motion of the surgical tools and the patient. Correctly scaled cut-views of the pre-operative computed tomography (CT) stack can be displayed on the overlay, orthogonal to the optical view or even including the direction of a clinical tool. Moreover, the system can manage three-dimensional models for tumours or bone structures and allows interaction with them using virtual tools, showing trajectories and distances. The mean error of the overlay was 0.7 mm. Clinical accuracy has shown results of 1.1–1.8 mm.
Popular media for HIV/AIDS prevention? Comparing two comics: Kingo and the Sara Communication Initiative
Authors: Beck Rose Marie
Published: November 2006

This paper draws attention to some assumptions implicit in HIV/AIDS communication or prevention campaigns which use popular culture media, in this instance comics. Theoretically the analysis is placed in a framework of popular culture as the arena of negotiations about claims over hegemonic discourses. Methodologically the internal logics of a local Swahili comic from the magazine Kingo and of a comic from the Sara Initiative in Swahili (UNICEF-ESARO) are explored through a comparative textual analysis, focusing on differences and convergences in the use of dramaturgy and characterisation of the protagonists. The transformations of locally known comic characters and the differences in dramaturgical strategies are made visible in the comparison, exposing the communicative, historical and social underpinnings of both comics. It is argued that as long as these preconditions of the international campaigns, as well as of local popular culture production are not thoroughly explored, hegemonic Western claims of knowledge of HIV/AIDS will be rejected by African people (and why not?). The paper recommends that prevention design allow for ‘moments of freedom’ understood ‘as the potential to transform one's thoughts, emotions and experience into creations that can be communicated and shared’ (Fabian 1998).
The local appropriation of democracy: an analysis of the municipal elections in Parakou, Republic of Benin, 2002–03
Authors: Bierschenk Thomas
Published: November 2006

Ever since the ‘democratic renewal’ of 1989–90, Benin has been regarded as a model democracy in the African context. The holding of local elections in 2002–03 can be seen as the culmination of this turn to democracy. Donors attach high expectations to decentralisation and local democracy. Based on an empirical analysis of municipal elections in Parakou, the country's third-largest city, the paper tries to gauge whether these expectations have been realised. The paper argues that while multi-party democracy has been instituted under considerable pressure from the outside, the particular form it has taken derives instead from rationales of national and local politics which go back to the late colonial period, and from recent developments in Benin's rent-based economy.
Subcellular distribution of theEntamoeba histolytica140 kDa FN-binding molecule during host-parasite interaction
Authors: HERNÁNDEZ-RAMÍREZ V. I. , RIOS A. , ANGEL A. , MAGOS M. A. , PÉREZ-CASTILLO L. , ROSALES-ENCINA J. L. , CASTILLO-HENKEL E. , TALAMÁS-ROHANA P.
Published: November 2006

Entamoeba histolyticatrophozoites recovered from the host-parasite interface during abscess development obtain different stimuli compared with long-term cultured cells. In order to have a better understanding about the mechanisms in which the 140 kDa fibronectin (FN)-binding molecule (EhFNR) is involved during the invasive process, we decided to compare the regulation process of this molecule among long-term cultured trophozoites, FN-stimulated trophozoites, and trophozoites recently recovered from a liver abscess. A cDNA clone (5A) containing a fragment of theEhFNR that shows identity to the C-terminal region of the intermediate galactose lectin subunit Igl, was selected with a mAb (3C10). Identity ofEhFNR with Igl was confirmed by immunoprecipitation with 3C10 and EH3015 (against the Gal/GalNAc intermediate subunit) mAbs. The 3C10 mAb was used as a tool to explore the modulation of the amoebic receptor (EhFNR). Our results showed specific regulation of theEhFNR in FN-interacted amoebas, as well as in trophozoites recovered at different stages of abscess development. This regulation involved mobilization of the receptor molecule from internal vesicles to the plasma membrane. Therefore, we suggest that in the host-parasite interface, theEhFNR (Igl) plays an important role in the adhesion process during abscess development.
Habitat and transmission – effect of tidal level and upstream host density on metacercarial load in an intertidal bivalve
Authors: THIELTGES D. W.
Published: November 2006

Transmission of parasites may be mediated by their habitat, consisting of abiotic and biotic components. I investigated the effect of 2 important habitat components in intertidal ecosystems, tidal level (abiotic) and density of upstream hosts (biotic), on the transmission of trematode cercariae to cockle (Cerastoderma edule) hosts. A field survey showed no general trend in metacercarial loads of cockles regarding tidal level but species-dependent reactions. Parasites originating from Littorina littorea (Himasthla elongata, Renicola roscovita) showed highest infection levels in the low intertidal while parasites originating from Hydrobia ulvae (H. continua, H. interrupta) showed highest infection levels in the mid-intertidal. This reflected the density of upstream hosts at both tidal levels and positive relationships between the density of upstream hosts and metacercarial load in cockles suggested the biotic habitat component to be the dominant factor in transmission. This was confirmed by a field experiment, manipulating tidal level and the density of infected upstream snail hosts. While tidal level had no significant effect on the number of metacercariae of H. elongata acquired by cockles, the effect of upstream host density was strong. In conclusion, although tidal level usually is a very important abiotic habitat component in intertidal ecosystems leading to conspicuous zonation patterns in free-living organisms, it seems of minor importance for trematode transmission. In contrast, the biotic component upstream host density is suggested to be the dominant predictor for trematode transmission to second intermediate hosts. Assessing the relative importance of abiotic and biotic habitat components in transmission is vital for the understanding of transmission processes in the field.
Thresholds for health and thresholds for illness: panic disorder versus subthreshold panic disorder
Authors: BATELAAN NEELTJE , DE GRAAF RON , VAN BALKOM ANTON , VOLLEBERGH WILMA , BEEKMAN AARTJAN
Published: November 2006

Background. There is increasing evidence that subthreshold forms of psychopathology are both common and clinically relevant. To enable classification of these subthreshold forms of psychopathology, it may be useful to distinguish not only a threshold for illness but also for health. Our aim was to investigate this with regard to panic.

Method. Data were derived from the Netherlands Mental Health Survey and Incidence Study (NEMESIS), which is based on a large representative sample of the adult general population (18–65 years) of The Netherlands (n=7076). The Composite International Diagnostic Interview was used as a diagnostic instrument. By defining two thresholds, three groups were formed: panic disorder, subthreshold panic disorder and no-panic. These groups were compared using multinomial regression analysis, χ2 and analysis of variance.

Results. The 12-month prevalence of panic disorder was 2·2% while that of subthreshold panic disorder was 1·9%. Symptom profiles and risk indicators associated with panic disorder and subthreshold panic disorder were similar, and half of the risk indicators were more strongly associated with panic disorder than with subthreshold panic disorder. Subthreshold panic disorder occupied an intermediate position between panic disorder and no-panic with regard to the number of symptoms, the percentage of subjects with co-morbidity, and functioning.

Conclusions. Subthreshold panic disorder is common, and seems clinically relevant, but is milder than panic disorder. These results thus support the use of a double threshold in panic. Further research should focus on the positioning of the thresholds, the course of subthreshold panic disorder and its treatment options.