bluuebunny/crossref_metadata_2025 huggingface dataset:
Paints and Coatings, 1. Introduction
Authors: Stoye Dieter , Marwald Birgit , Plehn Wolfgang
Published: April 2010

The article contains sections titled:

1.

Fundamental Concepts

2.

Historical Development

3.

Composition of Paints

3.1.

Binders and Resins

3.2.

Plasticizers

3.3.

Pigments and Extenders

3.4.

Paint Additives

3.5.

Solvents

4.

Paint Application

5.

Drying and Film Formation

6.

Multicoat Systems

7.

Economic Aspects

8.

Environmental Protection

8.1.

Clean Air Measures

8.2.

Wastewater

8.3.

Solid Residues and Waste

9.

Toxicology

10.

Future Outlook
Transport Phenomena, 1. Foundations
Authors: Flumerfelt Raymond W.
Published: April 2010

Transport phenomena is concerned with the analysis of processes involving the transport of mass, momentum, and energy. The focus of this article is the underlying foundations of transport phenomena, including the mathematical background, the basic laws of mechanics, as well as the mass and energy conservation laws. Cartesian tensor representation and analysis provides the mathematical framework and basic kinematic relations including the Reynolds Transport Theorem provide the relations for developing the basic equations of change from the governing fundamental laws, specifically, in the development of the equations of continuity, motion, and energy. In addition, the thermal and mechanical energy equations are developed and their relations to the equations of energy and motion are discussed. Further, the constitutive equations (or transport flux relations) governing simple and complex momentum and conduction heat transfer in materials are described and integrated with the basic equations of change. Finally, an overview of the solution framework and approaches for analyzing transport phenomena problems is summarized and discussed.

The article contains sections titled:

1.

Introduction

2.

Mathematical Preliminaries

2.1.

Coordinate Systems

2.2.

Vector and Tensor Operations

2.3

Vector and Tensor Representations – Curvilinear Coordinates

2.4.

The Jacobian

2.5.

Calculus of Vectors and Tensors

2.6.

Divergence Theorem

2.7.

Kinematic Relations

2.8.

Partial and Total Derivatives

2.9.

Relation Between Different Time Derivatives

3.

Basic Equations for Compositionally Homogeneous Systems

3.1.

The Reynolds Transport Theorem

3.2.

Conservation of Total Mass

3.3.

Conservation of Linear Momentum

3.4

Conservation of Angular Momentum

3.5

Mechanical Energy Equation

3.6

Conservation of Total Energy

3.7

Thermal Energy Equation

3.8

Forms of the Governing Equations

3.9

Entropy Inequality

3.10

Linear Transport Fluxes and Relations

3.11

Non‐Newtonian Fluids

3.12

Summary of Basic Equations

3.13

Boundary Conditions

3.14

Solution Philosophy

4

Dimensionless Equations of Change
Pigments, Inorganic, 5. Anticorrosive Pigments
Authors: Etzrodt Günter
Published: April 2010

The article contains sections titled:1.Principles2.Phosphate Pigments2.1.Zinc Phosphate2.2.Aluminum Phosphate2.3.Chromium Phosphate2.4.New Pigments Based on Metal Phosphates2.5.Multiphase Phosphate Pigments3.Other Phosphorus‐Containing Pigments4.Borosilicate Pigments5.Borate Pigments6.Chromate Pigments7.Molybdate Pigments8.Lead and Zinc Cyanamides9.Ion‐Exchange Pigments10.Metal Oxide Pigments10.1.Red Lead10.2.Calcium Plumbate10.3.Zinc and Calcium Ferrites10.4.Zinc Oxide11.Powdered Metal Pigments11.1.Zinc Dust11.2.Lead Powder12.Flake Pigments13.Organic Pigments14.Toxicology
Paints and Coatings, 4. Pigments, Extenders, and Additives
Authors: Köhler Klaus , Simmendinger Peter , Roelle Wolfgang , Scholz Wilfried , Valet Andreas , Slongo Mario
Published: April 2010

The article contains sections titled:1.Inorganic Pigments1.1.White Pigments1.2.Color Pigments2.Organic Pigments2.1.Properties2.2.Uses in Paints3.Extenders3.1.Introduction3.2.Properties3.3.Modification of Extenders4.Paint Additives4.1.Defoamers4.2.Wetting and Dispersing Additives4.3.Surface Additives4.4.Driers and Catalysts4.5.Preservatives4.6.Rheology Additives4.7.Light Stabilizers4.8.Commercial Products4.9.Use and Testing of Additives
Paints and Coatings, 6. Production Technology
Authors: Hiller Rainer
Published: April 2010

The article contains sections titled:1.Principles2.Paint‐Making Processes2.1.Varnishes2.2.Paints2.3.Powder Coatings3.Apparatus3.1.Mixers3.2.Dissolvers3.3.Kneaders and Kneader Mixers3.4.Media Mills3.5.Roller Mills3.6.Auxiliary Equipment
Paints and Coatings, 7. Paint Application
Authors: Meyer Bernd D. , Thomer Klaus Werner
Published: April 2010

The article contains sections titled:1.Types of Substrate2.Pretreatment of Substrate Surfaces2.1.Pretreatment of Metallic Substrates2.1.1.Cleaning2.1.2.Degreasing2.1.3.Formation of Conversion Layers2.2.Pretreatment of Plastics2.3.Pretreatment of Wood3.Application Methods3.1.Spraying (Atomization)3.2.Electrostatic Atomization3.3.Dipping3.4.Miscellaneous Wet Paint Coating Methods3.5.Powder Coating3.6.Coating of Plastics and Wood4.Paint Curing Methods
Paints and Coatings, 9. Application
Authors: Brandt Alfred , Milne Alex , Weyers Helmut
Published: April 2010

The article contains sections titled:1.Introduction2.Coating Systems for Corrosion Protection of Large Steel Constructions (Heavy‐Duty Coatings)3.Automotive Paints3.1.Car Body Paints3.2.Other Automotive Coatings4.Paints Used for Commercial Transport Vehicles4.1.Railroad Rolling Stock4.2.Freight Containers4.3.Road Transport Vehicles4.4.Aircraft Coatings5.Marine Coatings5.1.Substrate, Surface Preparation, and Priming5.2.Ship Paint Systems5.3.Fouling and Antifouling6.Coil Coating7.Coatings for Domestic Appliances8.Coatings for Packaging (Can Coatings)9.Furniture Coatings10.Coatings for Buildings10.1.Exterior‐Use Coatings10.2.Interior‐Use Coatings
Chromosome abnormalities investigated by non‐invasive prenatal testing account for approximately 50% of fetal unbalances associated with relevant clinical phenotypes
Authors: Grati Francesca Romana , Barlocco Andrea , Grimi Beatrice , Milani Silvia , Frascoli Giuditta , Di Meco Anna Maria , Liuti Rosaria , Trotta Anna , Chinetti Sara , Dulcetti Francesca , Ruggeri Anna Maria , De Toffol Simona , Clementi Maurizio , Maggi Federico , Simoni Giuseppe
Published: April 2010

During the past 20 years non‐invasive screening tests have been increasingly utilized in prenatal diagnosis (PD) practice. Considerable effort has been exerted by multicenter consortia to evaluate the reliability of non‐invasive screening tests in detecting those women with an increased risk of having a pregnancy affected by trisomies 21, 18, and 13, monosomy X, and triploidies. To what extent this group of abnormal karyotypes accounts for the total number of phenotypically relevant fetal chromosome abnormalities has, however, never been investigated. The present report is an attempt aimed to quantify this proportion. A retrospective analysis of a homogeneous survey of 115,128 consecutive invasive prenatal tests was undertaken. All cases were classified in accordance with the indication given for the invasive testing. Cytogenetic results regarding 96,416 karyotype analyses performed because of advanced maternal age (≥35 years) or gestational anxiety (<35 years) were considered since these are the patients who usually undergo non‐invasive screening tests. We calculated the number of cases (T21, T18, T13, 45,X, and triploidy) that would have been detected by prenatal screening on the basis of the published detection rate of the combined‐2 test or the quadruple test. Our findings indicate that the chromosomal abnormalities investigated by screening tests represent <50% of the fetal chromosomal abnormalities associated with an abnormal outcome ranging from intermediate‐to‐severe in women <35 years (45.8% and 39.6% in the first and second trimesters, respectively), and sensitivity >50% in women ≥35 years (65.1% and 61.8%, respectively). To conclude, approximately 50% of the phenotypically relevant abnormal karyotypes cannot be detected by non‐invasive prenatal screening tests. © 2010 Wiley‐Liss, Inc.
Behavioral responses of one western lowland gorilla (Gorilla gorilla gorilla) group at Bai Hokou, Central African Republic, to tourists, researchers and trackers
Authors: Klailova Michelle , Hodgkinson Chloe , Lee Phyllis C.
Published: April 2010

Gorilla tourism, widely perceived as a lucrative industry, is propelled by strong market demand with programs in five countries and for three of four gorilla subspecies. Human presence may negatively affect wild gorillas, potentially lowering immunity and increasing the likelihood of acquiring human‐borne disease. Yet, behavioral impacts of humans on wild gorilla behavior remain largely unexplored, particularly for western lowland gorillas. We evaluate the impact of tourist presence, human observer numbers (tourists, trackers, and researchers), and human observer distance on the behavior of one habituated gorilla group at Bai Hokou, Central African Republic. Behavioral data were collected for more than 12 months from January 2007. Of silverback aggressive events, 39% (N=229) were human directed, but 65% were low‐level soft barks. Adult females, and one in particular, were responsible for the highest number of aggressive events toward humans. Humans maintained closer proximity to the silverback when tourists were present, although tourist numbers had no significant impact on overall group activity budgets or rates of human‐directed aggression. However, as research team size increased, group feeding rates decreased. Close observer–silverback distance correlated with a decrease in his feeding rates and an increase in human monitoring. He directed less aggression toward observers at distances >10 m, although observers spent 48.5% of time between 6 and 10 m of the silverback. We discuss gorilla personality as a factor in human‐directed aggression. We explore whether the current 7 m distance limit governing gorilla tourism, based on disease transmission risks, is sufficient considering the potential behavioral stressor of close human presence. We recommend increasing minimum observation distance to >10 m where possible, decreasing observer group sizes, particularly after a visit consisting of maximum numbers and restricting tourist access to 1 visit/day. Am. J. Primatol. 72:897–906, 2010. © 2010 Wiley‐Liss, Inc.
Mating promiscuity and reproductive tactics in female black and gold howler monkeys (Alouatta caraya) inhabiting an island on the Parana river, Argentina
Authors: Kowalewski Martin M. , Garber Paul A.
Published: April 2010

In several primate species, females mate promiscuously and several adult males peacefully co‐reside in the same social group. We investigated female mating behavior in two neighboring multimale–multifemale groups of Alouatta caraya in northern Argentina (27°20′S–58°40′W). All adult individuals in each group were marked with identification anklets and ear tags, and followed for five consecutive full days per month during 20 consecutive months. We recorded 219 copulations for eight resident females in these two groups. Thirty‐two percent of matings involved extra‐group copulations and 68% were with resident males. During periods when females were likely to conceive and during periods when females were nonfertile (pregnancy and lactation), there were no significant differences in the average number of resident and nonresident males with which they copulated (G‐test: Gadj=0.1, df=3, P>0.05). In both of our study groups, adult males were tolerant of the mating activities between resident males and resident females, but acted aggressively and collectively (howling, border vigilance, and fighting) when extragroup males attempted to enter the group and mate with resident females. Given the frequency of extragroup matings, we examined the distance females traveled to engage in these copulations, time engaged in pre‐ and postcopulatory behavior, and the risk of injury during extragroup copulations. These costs were found to be relatively small. We suggest that female promiscuity is the prime driver or constraint on male reproductive opportunities in this species. Female promiscuity in A. caraya appears to represent a mixed mating strategy that may serve to increase opportunities for genetic diversity between a female's successive offspring as well as minimize the risk of infanticide by spreading paternity estimates across a larger number of adult males. Am. J. Primatol. 72:734–748, 2010. © 2010 Wiley‐Liss, Inc.
A comparative analysis of internal cranial anatomy in the hylobatidae
Authors: Leslie Erin Rae
Published: April 2010

Craniometric studies on the hylobatids using external metrics (Creel and Preuschoft, 1976, 1984) sorted hylobatid populations into primary species groupings which are in accordance with the four currently recognized generic‐level groupings. The goal of the current study was to assess the relative orientations of the orbits, palate, and basioccipital clivus among the hylobatid genera in an effort to further clarify whether the lesser apes differ significantly in these internal cranial features and how that variation patterns across the groups. Nine angular variables quantifying orbital, palatal, and basioccipital clivus orientations were measured on lateral view radiographs of adults representing three of the four hylobatid genera: Hylobates; Nomascus; and, Symphalangus. The interspecific adult hylobatid means for the angular variables were analyzed using t‐test contrasts. The total sample was further subjected to discriminant function analysis (DFA) to test for the ability of craniofacial angular variables to distinguish the hylobatid genera from one another. The three hylobatid genera displayed significant morphological differentiation in orbital, palatal, and posterior skull base orientations. Normal, jackknifed, and cross‐validation DFA procedures correctly identified the hylobatids 50–100% of the time. The observed morphological patterns generally mapped onto the findings of earlier external craniometric hylobatid studies and suggest concordance between specific internal and external cranial features. This article is the first comprehensive study of variation in internal cranial anatomy of the Hylobatidae and includes the first published craniofacial angular data for Nomascus. Am J Phys Anthropol 143:250–265, 2010. © 2010 Wiley‐Liss, Inc.
Solid–solid reaction in a fluidized bed
Authors: Murthy J.S.N. , Surendar Reddy V. , Sankarshana T.
Published: April 2010

Solid–solid reactions, although of considerable industrial importance, have not received significant attention in the chemical engineering literature. In conventional method of manufacturing products using reactants in solid phase, the rate of heat transfer and rate of diffusion are very slow. In order to overcome these problems, an attempt is made to investigate these reactions employing a stirred fluidized bed. The addition reaction of phthalic anhydride and p‐nitro aniline system that takes place between 80 and 120 °C, forming phthaloyl derivative of p‐nitro aniline is selected for the investigations. The reaction is conducted in a stainless steel column of 0.1 m diameter and 1‐m height. The variables considered are reaction temperature, stirrer speed, flow rate of fluidizing medium, and static bed height. Experiments are performed using statistically designed factorial experiments. Data are used to find the model suitable to the mechanism of the reaction. Mathematical equations relating reaction parameters viz., steady state conversion, time for steady state conversion, reaction rate constant, and activation energy with operating variables are developed and activation energy is reduced from 14 kcal/mol reported in literature to less than 5.3 kcal/mol depending on operating conditions. The concept could be adopted for the manufacture of cement, and other materials with required modifications of experimental setup. Copyright © 2010 Curtin University of Technology and John Wiley & Sons, Ltd.
Hybrid modelling and kinetic estimation for polystyrene batch reactor using Artificial Neutral Network (ANN) approach
Authors: Hosen Mohammad Anwar , Hussain Mohd Azlan , Mjalli Farouq S
Published: April 2010

Modelling polymerization processes involves considerable uncertainties due to the intricate polymerization reaction mechanism involved. The complex reaction kinetics results in highly nonlinear process dynamics. Available conventional models are limited in applicability and cannot describe accurately the actual physico‐chemical characteristics of the reactor dynamics. The usual practice for operating polymerization reactors is to optimize the reactor temperature profile because the end use properties of the product polymer depend highly on temperature. However, to obtain accurate models in order to optimize the temperature profile, the kinetic parameters (i.e. frequency factors and activation energies) for a specific reactor must be determined accurately. Kinetic parameters vary considerably in batch reactors because of its high sensitivity to other reactor design and operational variables such as agitator geometry and speed, gel effects, heating systems, etc. In this work, the kinetic parameters were estimated for a styrene‐free radical polymerization conducted in an experimental batch reactor system using a nonlinear least squares optimization algorithm. The estimated kinetic parameters were correlated with respect to reactor operating variables including initial reactor temperature (To), initial initiator concentration (Io) and heat duty (Q) using artificial neural network (ANN) techniques. The ANN kinetic model was then utilized in combination with the conventional mechanistic model. The experimental validation of the model revealed that the new model has high prediction capabilities compared withother reported models. Copyright © 2010 Curtin University of Technology and John Wiley & Sons, Ltd.
Human assessments of document similarity
Authors: Westerman S.J. , Cribbin T. , Collins J.
Published: April 2010

Two studies are reported that examined the reliability of human assessments of document similarity and the association between human ratings and the results of n‐gram automatic text analysis (ATA). Human interassessor reliability (IAR) was moderate to poor. However, correlations between average human ratings and n‐gram solutions were strong. The average correlation between ATA and individual human solutions was greater than IAR. N‐gram length influenced the strength of association, but optimum string length depended on the nature of the text (technical vs. nontechnical). We conclude that the methodology applied in previous studies may have led to overoptimistic views on human reliability, but that an optimal n‐gram solution can provide a good approximation of the average human assessment of document similarity, a result that has important implications for future development of document visualization systems.
Effects of 2G and 3G mobile phones on human alpha rhythms: Resting EEG in adolescents, young adults, and the elderly
Authors: Croft R.J. , Leung S. , McKenzie R.J. , Loughran S.P. , Iskra S. , Hamblin D.L. , Cooper N.R.
Published: April 2010

The present study was conducted to determine whether adolescents and/or the elderly are more sensitive to mobile phone (MP)‐related bioeffects than young adults, and to determine this for both 2nd generation (2G) GSM, and 3rd generation (3G) W‐CDMA exposures. To test this, resting alpha activity (8–12 Hz band of the electroencephalogram) was assessed because numerous studies have now reported it to be enhanced by MP exposure. Forty‐one 13–15 year olds, forty‐two 19–40 year olds, and twenty 55–70 year olds were tested using a double‐blind crossover design, where each participant received Sham, 2G and 3G exposures, separated by at least 4 days. Alpha activity, during exposure relative to baseline, was recorded and compared between conditions. Consistent with previous research, the young adults' alpha was greater in the 2G compared to Sham condition, however, no effect was seen in the adolescent or the elderly groups, and no effect of 3G exposures was found in any group. The results provide further support for an effect of 2G exposures on resting alpha activity in young adults, but fail to support a similar enhancement in adolescents or the elderly, or in any age group as a function of 3G exposure. Bioelectromagnetics 31:434–444, 2010. © 2010 Wiley‐Liss, Inc.
Experimentelle und numerische Untersuchungen zum Einfluss der Bewehrungskorrosion auf das Verbundverhalten zwischen Stahl und Beton
Authors: Fischer Christian , Ožbolt Joško , Gehlen Christoph
Published: April 2010

Im vorliegenden Aufsatz werden Ergebnisse aus experimentellen und numerischen Untersuchungen an so genannten Balkenend (engl. beam end) Probekörpern zum Einfluss der Stahlkorrosion auf das Verbundtragverhalten vorgestellt. Dabei wurden geometrische Einflüsse, wie Stabdurchmesser und Betondeckung sowie Einflüsse aufgrund von Bügelbewehrung und deren Schwächung durch die Korrosion untersucht. Insgesamt ergaben sich sechs verschiedene Probekörpertypen, an denen Ausziehversuche ohne Korrosion und zu unterschiedlichen Korrosionsstadien durchgeführt wurden. Dabei wurden korrosionsbedingte, maximale Rissbreiten von bis zu rd. w = 1,3 mm mit dazugehörigen Korrosionsabträgen von maximal bis zu xcorr = 500 μm untersucht. Die Untersuchungen ergaben, dass die Verbundfestigkeit von Probekörpern ohne Bügelbewehrung mit zunehmender Korrosion exponentiell abnimmt. Probekörper mit Bügeln weisen hingegen kaum Verbundfestigkeitsverluste bis zur untersuchten Rissbreite von w = 0,6 mm auf. Die umschließende Wirkung der Bügel wurde unter den untersuchten Bedingungen nicht beeinflusst. Ein erarbeitetes numerisches FE‐Modell konnte die experimentellen Ergebnisse gut reproduzieren.

Experimental and Numerical Investigations on Bond Behaviour of Corroded Reinforcement

The following paper presents experimental and numerical results on the effect of rebar corrosion on bond between ribbed reinforcing bars and concrete. The investigations are performed on beam end specimens. The key aspects of the investigation were the study of different geometrical parameters as bar diameter and concrete cover as well as the effects of confining reinforcement and their impairment due to corrosion. Altogether six different types of specimens were tested without corrosion and at different corrosion levels. The resulting maximum crack widths were around w = 1.3 mm with corresponding penetration depths of xcorr = 500 μm. The studies showed that bond strength of specimens without stirrups decreased exponentially with increasing corrosion, whereas specimens with stirrups showed almost no loss of bond strength up to the investigated crack width of w = 0.6 mm. The confining action of stirrups was not impaired by corrosion within the studied conditions. The used FE code is able to realistically reproduce the results of experimental investigations.
Optimierte Zustandsprognose durch kombinierte Verfahren
Authors: Gehlen Christoph , von Greve‐Dierfeld Stefanie
Published: April 2010

Die große Zahl von korrosionsinduzierten Schäden an Infrastrukturbauwerken und der damit verbundene hohe Kostenaufwand für Instandhaltungsmaßnahmen macht eine Beurteilung der Zuverlässigkeit (Gebrauchstauglichkeit, Tragfähigkeit) solcher Bauwerke für die verbleibende Nutzungszeit immer bedeutender. Am Beispiel einer Tiefgarage wird gezeigt, wie durch Verknüpfung von Bauwerksuntersuchung und vollprobabilistischer Lebensdauerbetrachtung (Zuverlässigkeitsberechnung) eine gezielte und ortsgenaue Beschreibung des Bauwerkszustandes grenzzustandsbezogen erfolgen kann. Durch Kombination beider Elemente (Bauwerksuntersuchung/Zuverlässigkeitsberechnung) können Instandsetzungszeitpunkt und Instandsetzungsumfang entsprechend den örtlichen Bedingungen abgeleitet und eine kosteneffiziente und minimalinvasive Instandsetzungsstrategie erarbeitet werden.

Improving the Prediction of Condition State by Combining Different Methods

Corrosion of reinforcement is the primary cause for the structural deterioration of reinforced concrete structures exposed to corrosive/ chloride environments. Corrosion results in high costs for infrastructure maintenance. Thus assessment of existing structures in terms of required structural performance (serviceability and safety performance level) is of increasing importance. Using a car park as an example, it is explained how the time dependent and area related/spatial development of the condition state of the structure are described by means of combining a full‐probabilistic deterioration model with results from condition control. This enables a cost‐optimal maintenance strategy, based on the dependence of the deterioration process on time and location.
Weiße Wannen mit hochwertiger Nutzung – Chancen und Risiken im Hochbau
Authors: Fastabend Michael , Eßer Angelika , Schücker Barbara , Albert Mark
Published: April 2010

Ausgehend von den Grundprinzipien der Konstruktion von Untergeschossen in der Bauart Weißer Wannen werden zunächst die Nutzungen in ihrer Veränderung im Verlauf der letzten 20 Jahre aufgezeigt. Es wird dargestellt, dass die moderne Nutzung von Gewerbebauten in den Untergeschossen zu einem sehr großen Anteil als hochwertig eingeordnet werden kann zur Unterbringung von Technik, Lagern oder Einzelhandel. Für diese Nutzungskonzepte werden die technischen und entwurflichen Randbedingungen von WU‐Konstruktionen diskutiert. Neben der Trennung von wasserundurchlässigem Rohbau und raumbildendem Ausbau werden Risiken der Undichtheit für unterschiedliche Bauteile einer Analyse unterzogen. Abschließend werden aus vorliegenden Erfahrungen Empfehlungen für die Konstruktion, Qualitätssicherung und Wartung von Weißen Wannen mit hochwertiger Nutzung ausgesprochen.

Watertight Concrete Construction in High Quality Use Chances and Risks of Structural Engineering

Coming from the basic principles of the construction of basements as a watertight concrete construction there will first of all be a presentation of its use and change during the last 20 years. It is going to be illustrated that a modern use of commercial buildings in the basements – i.e. placing of technics, storage or retail – can most often be classified as high quality. For these utilisation concepts the technical and design related boundary conditions of watertight constructions will be discussed. Besides of the separation of a watertight carcass and space creating construction there will also be an analysis of the risks of leakage for different structural elements. Concluding there will be recommendations resulting from present experiences concerning construction, quality assurance and maintenance of watertight concrete constructions in high quality use.
Ertüchtigung der beiden Eisenbahnbrücken A13
Authors: Roeser Wolfgang , Kerkeni Naceur
Published: April 2010

Wesentliche Teile unserer Infrastruktur wurden durch die intensive Bautätigkeit in den 1950er bis 1970er Jahren erschaffen. Zahleiche Bauwerke im Bestand sind allerdings “in die Jahre gekommen” und entsprechen nicht mehr uneingeschränkt dem heutigen Stand der Technik. Im vorliegenden Beitrag wird am Beispiel von zwei vorgespannten Eisenbahnrahmenbrücken gezeigt, wie durch differenzierte Betrachtung und eine behutsame Ertüchtigung eine nachhaltige und wirtschaftliche Nutzung dieser Bauwerke in einem weiteren Lebenszyklus möglich ist.
The role of UV‐irradiation pretreatment on the degradation of 2,4‐dichlorophenoxyacetic acid in water
Authors: Tchaikovskaya O. , Sokolova I. , Mayer G.V. , Karetnikova E. , Lipatnikova E. , Kuzmina S. , Volostnov D.
Published: April 2010

The degradation of 2,4‐dichlorophenoxyacetic acid (2,4‐D) in water by the combination process of UV‐irradiation, humic acids and activated sludge treatment has been studied. The photoreaction rate of all irradiated samples was lowest for the sample irradiated at 308 nm (the XeCl excilamp) in the absence and in the presence of humic acids, and highest for the sample irradiated at 222 nm (the KrCl excilamp). Photolysis of 2,4‐D has been shown to enhance the subsequent microbial degradation. Copyright © 2010 John Wiley & Sons, Ltd.
The relationship between exhaled carbon monoxide and human neutrophil function in the Japanese general population
Authors: Mikami Makoto , Takahashi Ippei , Matsuzaka Masashi , Danjo Kazuma , Yamai Kiyonori , Inoue Ryo , Iwane Kaori , Umeda Takashi , Nakaji Shigeyuki
Published: April 2010

We have evaluated the relationship between exhaled carbon monoxide (CO) level and neutrophil‐related functions such as reactive oxygen species (ROS) production capability, phagocytic activity and serum opsonic activity in the general population. Serum opsonic activity was determined by measuring the effects of serum on neutrophil ROS production capability using lucigenin‐ and luminol‐dependent chemiluminescence (LgCL, LmCL). LgCL is associated with the detection of O2−, whereas LmCL mainly detects H2O2 and HOCl, which are higher reactive oxygen radicals. In females, exhaled CO level was found to have positive associations with ROS production capability and LgCL. However, the opposite tendency was seen between exhaled CO level and LmCL in both genders. This result suggests that neutrophil ROS production in females may have contributed to oxidative stress, which led to the increases in intrinsic CO and exhaled CO consequently. Such changes then may have inhibited the process of changing reactive oxygen radicals into higher oxidizing potential levels. Copyright © 2010 John Wiley & Sons, Ltd.
Quercetin accumulation by chronic administration causes the caspase‐3 activation in liver and brain of mice
Authors: Choi Eun Jeong , Kim Gun‐Hee
Published: April 2010

Quercetin is an excellent antioxidant that has a variety of side effects. This study investigated whether the chronic administration of quercetin in mice induces apoptosis. Mice were divided randomly into three treatment groups. Quercetin was administered orally to two of three groups at 100 and 250 mg/kg body weight (BW) for 18 days. The serum quercetin level increased in a dose‐dependent manner, although the quercetin levels in the liver and brain were lower than in serum. Nevertheless, quercetin induced apoptosis in both the liver and brain, as evidenced by increased caspase‐3 expression and activity. Quercetin‐induced apoptosis seems to be associated with quercetin accumulation. Moreover, with quercetin accumulation, the brain was more susceptible to apoptosis than the liver. In conclusion, quercetin administration at a high dose may lead to apoptosis in the liver and brain of mouse.
Enhancement of shortening velocity, power, and acto‐myosin crossbridge (CB) kinetics following long‐term treatment with propionyl‐L‐carnitine, coenzyme Q10, and omega‐3 fatty acids in BIO TO‐2 cardiomyopathic Syrian hamsters papillary muscle
Authors: Vargiu Romina , Littarru Gian Paolo , Fraschini Matteo , Perinu Anna , Tiano Luca , Capra Alessandro , Mancinelli Rino
Published: April 2010

Impaired functions of myocardial muscle cells in human and animals, is a primary defect associated with idiopathic dilated cardiomyopathy (DCM). The pathophysiological mechanisms implicated in the DCM are yet to be clarified and an effective therapy is still not available. The BIO TO‐2 cardiomyopathic Syrian Hamsters (CMSHs) represent an animal model of idiopathic DCM. The aim of this study was to investigate the effect of long‐term treatment (2 months) with propionyl‐L‐carnitine (PLC), coenzyme Q10, omega‐3 fatty acids and a combination of these three agents (formulation HS12607) on mechanical properties and acto‐myosin crossbridges (CBs) kinetics of left ventricular (LV) papillary muscle from control and treated 10 month old BIO TO‐2 CMSHs. Isometric and isotonic contractile properties of isolated papillary muscle from control and treated CMSHs were investigated, and acto‐myosin CB number, force and kinetics were calculated using Huxley's equations. Mechanical parameter values were higher in treated than in control hamsters, particularly when substances were administered together in a coformulation (HS12607). Compared to control, HS12607‐treated papillary muscles showed a significant increase of maximum peak isometric tension (Po) (30.06 ± 4.91 vs. 19.74 ± 5.00 mN/mm2), maximum extent of muscle shortening (0.13 ± 0.03 vs. 0.07 ± 0.02 L/Lmax), maximum unloaded shortening velocity (1.18 ± 0.24 vs. 0.53 ± 0.13 L/Lmax s−1) and maximum peak of power output (5.52 ± 1.61 vs. 1.58 ± 0.83). The curvature of the hyperbolic force‐velocity relationships did not differ between control and treated hamsters. When compared to controls, acto‐myosin CB number increased in treated hamsters [(6.67 ± 1.91) 1010/mm2 vs. (3.55 ± 2.08) 1010/mm2], whereas the unitary force of single CB was similar in control and treated animals. The peak value of the rate constant for CB attachment (f1) and detachment (g2) was higher in treated animals when compared to control. (93.87 ± 25.82 vs.47.28 ± 10.88 s−1 and 214.40 ± 44.64 vs. 95.56 ± 23.49 s−1, respectively). In conclusion, the present study illustrates that supplementation with PLC, CoQ10 and omega‐3 fatty acids improved motor parameters, energetic, and CB kinetics of BIO TO‐2 CMSH papillary muscle indicating that these naturally occurring substances may be a valid adjuvant to conventional therapy in DCM.
Emergence of protein kinase CK2 as a key target in cancer therapy
Authors: Trembley Janeen H. , Chen Zhong , Unger Gretchen , Slaton Joel , Kren Betsy T. , Van Waes Carter , Ahmed Khalil
Published: April 2010

Protein kinase CK2, a protein serine/threonine kinase, plays a global role in activities related to cell growth, cell death, and cell survival. CK2 has a large number of potential substrates localized in diverse locations in the cell including, for example, NF‐κB as an important downstream target of the kinase. In addition to its involvement in cell growth and proliferation it is also a potent suppressor of apoptosis, raising its key importance in cancer cell phenotype. CK2 interacts with diverse pathways which illustrates the breadth of its impact on the cellular machinery of both cell growth and cell death giving it the status of a “master regulator” in the cell. With respect to cancer, CK2 has been found to be dysregulated in all cancers examined demonstrating increased protein expression levels and nuclear localization in cancer cells compared with their normal counterparts. We originally proposed CK2 as a potentially important target for cancer therapy. Given the ubiquitous and essential for cell survival nature of the kinase, an important consideration would be to target it specifically in cancer cells while sparing normal cells. Towards that end, our design of a tenascin based sub‐50 nm (i.e., less than 50 nm size) nanocapsule in which an anti‐CK2 therapeutic agent can be packaged is highly promising because this formulation can specifically deliver the cargo intracellularly to the cancer cells in vivo. Thus, appropriate strategies to target CK2 especially by molecular approaches may lead to a highly feasible and effective approach to eradication of a given cancer.
Trichloroethene and cis‐1,2‐dichloroethene concentration‐dependent toxicity model simulates anaerobic dechlorination at high concentrations: I. batch‐fed reactors
Authors: Sabalowsky Andrew R. , Semprini Lewis
Published: April 2010

A model was developed to describe toxicity from high concentrations of chlorinated aliphatic hydrocarbons (CAHs) on reductively dechlorinating cultures under batch‐growth conditions. A reductively dechlorinating anaerobic Evanite subculture (EV‐cDCE) was fed trichloroethene (TCE) and excess electron donor to accumulate cis‐1,2‐dichloroethene (cDCE) in batch‐fed reactors. A second Point Mugu (PM) culture was also studied in the cDCE accumulating batch‐fed experiment, as well as in a time‐ and concentration‐dependent cDCE exposure experiment. Both cultures accumulated cDCE to concentrations ranging from 9,000 to 12,000 µM before cDCE production from TCE ceased. Exposure to approximately 3,000 and 6,000 µM cDCE concentrations for 5 days during continuous TCE dechlorination exhibited greater loss in activity proportional to both time and concentration of exposure than simple endogenous decay. Various inhibition models were analyzed for the two cultures, including the previously proposed Haldane inhibition model and a maximum threshold inhibition model, but neither adequately fit all experimental observations. A concentration‐dependent toxicity model is proposed, which simulated all the experimental observations well. The toxicity model incorporates CAH toxicity terms that directly increase the cell decay coefficient in proportion with CAH concentrations. We also consider previously proposed models relating toxicity to partitioning in the cell wall (KM/B), proportional to octanol–water partitioning (KOW) coefficients. A reanalysis of previously reported modeling of batch tests using the Haldane model of Yu and Semprini, could be fit equally well using the toxicity model presented here, combined with toxicity proportioned to cell wall partitioning. A companion paper extends the experimental analysis and our modeling approach to a completely mixed reactor and a fixed film reactor. Biotechnol. Bioeng. 2010;107: 529–539. © 2010 Wiley Periodicals, Inc.
Electricity generation from the treatment of wastewater with a hybrid up‐flow microbial fuel cell
Authors: Katuri Krishna P. , Scott K.
Published: April 2010

The performance of a prototype up‐flow single‐chambered microbial fuel cell (MFC) for electrical power generation using brewery wastewater as fuel is reported. The designed reactor consisted of three zones, namely a lower anaerobic digestion zone, a central MFC zone, and an upper effluent clarifier zone. Tests were conducted in batch mode using a beer wastewater as the fuel/electron donor (COD concentration: 430 mg/L) and mixed consortia (both sewage microflora and anaerobic sludge) as a source of electrogenic bacteria. A stable current density of ∼2,270 mA/m2 was generated under continuous polarization with a constant external resistance (0.01 kΩ) and cell polarization gave a peak power density of 330 mW/m2 at a current density of 1,680 mA/m2. Electrochemical impedance analysis showed that the overall internal resistance of the reactor was quite low, that is, 8.0 Ω. Cyclic voltammetric analysis of the anodic biofilm at low scan rate revealed quite complex processes at the anode, with three redox peaks, at potentials of 116, 214, and 319 mV (vs. NHE). Biotechnol. Bioeng. 2010;107: 52–58. © 2010 Wiley Periodicals, Inc.
Mechanisms of unintended amino acid sequence changes in recombinant monoclonal antibodies expressed in Chinese Hamster Ovary (CHO) cells
Authors: Guo Donglin , Gao Albert , Michels David A. , Feeney Lauren , Eng Marian , Chan Betty , Laird Michael W. , Zhang Boyan , Yu X. Christopher , Joly John , Snedecor Brad , Shen Amy
Published: April 2010

An amino acid sequence variant is defined as an unintended amino acid sequence change and contributes to product heterogeneity. Recombinant monoclonal antibodies (MAbs) are primarily expressed from Chinese Hamster Ovary (CHO) cells using stably transfected production cell lines. Selections and amplifications with reagents such as methotrexate (MTX) are often required to achieve high producing stable cell lines. Since MTX is often used to generate high producing cell lines, we investigated the genomic mutation rates of the hypoxanthine–guanine phosphoribosyltransferase (HGPRT or HPRT) gene using a 6‐thioguanine (6‐TG) assay under various concentrations of MTX selection in CHO cells. Our results show that the 6‐TG resistance increased as the MTX concentration increased during stable cell line development. We also investigated low levels of sequence variants observed in two stable cell lines expressing different MAbs. Our data show that the replacement of serine at position 167 by arginine (S167R) in the light chain of antibody A (MAb‐A) was due to a genomic nucleotide sequence change whereas the replacement of serine at position 63 by asparagine (S63N) in the heavy chain of antibody B (MAb‐B) was likely due to translational misincorporation. This mistranslation is codon specific since S63N mistranslation is not detectable when the S63 AGC codon is changed to a TCC or TCT codon. Our results demonstrate that both a genomic nucleotide change and translational misincorporation can lead to low levels of sequence variants and mistranslation of serine to asparagine can be eliminated by substituting the TCC or TCT codon for the S63 AGC codon without impacting antibody productivity. Biotechnol. Bioeng. 2010;107: 163–171. © 2010 Wiley Periodicals, Inc.
Establishing benchmarks for the outcome of herniotomy in children
Authors: Vogels H D E , Bruijnen C J P , Beasley S W
Published: April 2010

Background

Although complication rates following herniotomy in children are low, reported rates vary. The aim of this study was to propose desirable outcome measures that can be used by surgeons to assess the quality of their service.

Methods

A review of prospectively collected data on all hernias operated on by the Christchurch-based paediatric surgical service was undertaken. Complication rates were determined and compared with those reported in the literature. Rates for children aged 1 year or above were compared with those in children aged less than 1 year.

Results

There were 3128 herniotomies performed, with an overall recurrence rate of 0·6 per cent. Wound infections occurred in 0·9 per cent, but were confined to infants aged less than 12 months. The rate of acquired cryptorchidism was 0·4 per cent and testicular atrophy 0·8 per cent in boys. Injury to the vas deferens was recognized in 0·1 per cent. Children under 1 year of age were more likely to develop recurrence than older children (0·9 versus 0·2 per cent respectively; odds ratio 4·56, P = 0·013).

Conclusion

Complication rates were relatively low compared with those reported previously, but were considered achievable in most paediatric surgical units. Specific attention should be paid to the youngest infants, as this group has the highest complication rate. Minimum standards can be proposed based on these and other published outcomes.
Effect of parathyroidectomy for primary hyperparathyroidism on bone mineral density in postmenopausal women
Authors: Sitges-Serra A , García L , Prieto R , Peña M J , Nogués X , Sancho J J
Published: April 2010

Background

The bone mineral density (BMD) response to parathyroidectomy is heterogeneous and difficult to predict. Available data come from mixed populations of men and women, of different age and degrees of disease severity, and preoperative BMD loss.

Methods

This was a longitudinal, prospective cohort study of 103 postmenopausal women with osteopenia or osteoporosis at the femoral neck site, successfully operated on for primary hyper parathyroidism. BMD and metabolic variables were recorded before and 1 year after parathyroidectomy.

Results

After surgery, there was a 1·3 per cent increase in the median BMD at the femoral neck site (0·615 versus 0·623 g/cm2; P = 0·001). Overall, positive responses were also observed at total hip (0·4 per cent) and lumbar spine (2·3 per cent) sites. Analysing the individual responses, however, only 45 (46 per cent) of 97 patients showed a significant (at least 3·7 per cent) increase in BMD at the femoral neck site compared with the preoperative value and 52 had a decreased (15) or unchanged (37) femoral neck BMD. Patients who gained BMD were younger, had more severe hyperparathyroidism and better renal function.

Conclusion

Almost half of the postmenopausal women with hyperparathyroidism and low BMD have a significant remineralization response 1 year after parathyroidectomy. Differential mineralization responses of BMD after surgery appear to be related to severity of primary hyperparathyroidism, age and renal function.
Bacterial lipopolysaccharide promotes profibrotic activation of intestinal fibroblasts
Authors: Burke J P , Cunningham M F , Watson R W G , Docherty N G , Coffey J C , O'Connell P R
Published: April 2010

Background

Fibroblasts play a critical role in intestinal wound healing. Lipopolysaccharide (LPS) is a cell wall component of commensal gut bacteria. The effects of LPS on intestinal fibroblast activation were characterized.

Methods

Expression of the LPS receptor, toll-like receptor (TLR) 4, was assessed in cultured primary human intestinal fibroblasts using flow cytometry and confocal microscopy. Fibroblasts were treated with LPS and/or transforming growth factor (TGF) β1. Nuclear factor κB (NFκB) pathway activation was assessed by inhibitory κBα (IκBα) degradation and NFκB promoter activity. Fibroblast contractility was measured using a fibroblast-populated collagen lattice. Smad-7, a negative regulator of TGF-β1 signalling, and connective tissue growth factor (CTGF) expression were assessed using reverse transcriptase–polymerase chain reaction and western blot. The NFκB pathway was inhibited by IκBα transfection.

Results

TLR-4 was present on the surface of intestinal fibroblasts. LPS treatment of fibroblasts induced IκBα degradation, enhanced NFκB promoter activity and increased collagen contraction. Pretreatment with LPS (before TGF-β1) significantly increased CTGF production relative to treatment with TGF-β1 alone. LPS reduced whereas TGF-β1 increased smad-7 expression. Transfection with an IκBα plasmid enhanced basal smad-7 expression.

Conclusion

Intestinal fibroblasts express TLR-4 and respond to LPS by activating NFκB and inducing collagen contraction. LPS acts in concert with TGF-β1 to induce CTGF. LPS reduces the expression of the TGF-β1 inhibitor, smad-7.
Adverse effects of polyvinylidene fluoride-coated polypropylene mesh used for laparoscopic intraperitoneal onlay repair of incisional hernia
Authors: Fortelny R H , Petter-Puchner A H , Glaser K S , Offner F , Benesch T , Rohr M
Published: April 2010

Background

Polyvinylidene fluoride-coated polypropylene meshes have been developed specifically for intraperitoneal onlay mesh repair. They combine a macroporous design with biomechanical characteristics compatible with the abdominal wall and are reported to have favourable antiadhesive properties. This retrospective study reports complications related to one of these materials, DynaMesh®.

Methods

Twenty-nine patients underwent intraperitoneal onlay mesh repair with DynaMesh® at one of two hospitals. Patients characteristics, surgical procedures and postoperative analgesia were comparable at both sites.

Results

Six patients developed DynaMesh®-related complications that required surgical reintervention by laparotomy within 1 year of operation. Surgical reintervention was for adhesions in five patients and the mesh had to be explanted in three. One mesh was explanted because of early infection. Adhesions to DynaMesh® were found in two patients who had surgery for unrelated reasons.

Conclusion

Laparoscopic intraperitoneal onlay DynaMesh® repair was associated with a high rate of complications.