bluuebunny/crossref_metadata_2025 huggingface dataset:
Factors that distinguish serious versus less severe Strain and sprain injuries: An analysis of electric utility workers
Authors: Kelsh Michael A. , Fordyce Tiffani A. , Lau Edmund C. , Mink Pamela J. , Morimoto Libby M. , Lu Elizabeth T. , Yager Janice W.
Published: December 2008

Background

Occupational sprain and strain injuries are one of the most common types of nonfatal occupational injuries and a significant source of lost workdays. This study examines factors associated with severe work‐related sprain/strain injuries to the back, shoulder, and knees.

Methods

A synthetic case–control study was performed (controls were selected from the same pool of utility workers as cases). Cases included all electric utility workers who had experienced a severe work‐related sprain/strain injury to the back, knee, or shoulder. Primary controls were selected from all workers who had sustained a minor injury. Secondary controls were selected from employees with a minor sprain/strain injury to the back, knee, or shoulder. Multivariate logistic regression models were used to estimate odds ratios and 95% confidence intervals.

Results

Workers 41 years and older were more likely to have experienced severe shoulder sprain/strain injuries [Age 41–50: OR = 3.62, 95% CI: 1.71–7.65; age 51 and older: OR = 4.49, 95% CI: 1.89–10.67] and severe back sprain/strain injuries [Age 41–50: OR = 1.70, 95% CI: 1.06–2.33; age 51 and older: OR = 1.5, 95% CI: 0.90–2.52]. Line workers and maintenance workers had an increased risk of serious sprain/strain injuries. Gender and day of week were not significantly associated with sprain/strain injuries.

Discussion

Though this study is limited by available data, future studies may benefit from this preliminary examination of occupational and demographic characteristics associated with serious sprain/strain injuries among electric utility workers. Am. J. Ind. Med. 52:210–220, 2009. © 2008 Wiley‐Liss, Inc.
Estimation of health‐care costs for work‐related injuries in the Mexican Institute of social security
Authors: Carlos‐Rivera Fernando , Aguilar‐Madrid Guadalupe , Gómez‐Montenegro Pablo Anaya , Juárez‐Pérez Cuauhtémoc A. , Sánchez‐Román Francisco Raúl , Durcudoy Montandon Jaqueline E.A. , Borja‐Aburto Víctor Hugo
Published: December 2008

Background

Data on the economic consequences of occupational injuries is scarce in developing countries which prevents the recognition of their economic and social consequences. This study assess the direct heath care costs of work‐related accidents in the Mexican Institute of Social Security, the largest health care institution in Latin America, which covered 12,735,856 workers and their families in 2005.

Methods

We estimated the cost of treatment for 295,594 officially reported occupational injuries nation wide. A group of medical experts devised treatment algorithms to quantify resource utilization for occupational injuries to which unit costs were applied. Total costs were estimated as the product of the cost per illness and the severity weighted incidence of occupational accidents.

Results

Occupational injury rate was 2.9 per 100 workers. Average medical care cost per case was $2,059 USD. The total cost of the health care of officially recognized injured workers was $753,420,222 USD. If injury rate is corrected for underreporting, the cost for formal injured workers is 791,216,460. If the same costs are applied for informal workers, approximately half of the working population in Mexico, the cost of healthcare for occupational injuries is about 1% of the gross domestic product.

Conclusions

Health care costs of occupational accidents are similar to the economic direct expenditures to compensate death and disability in the social security system in Mexico. However, indirect costs might be as important as direct costs. Am. J. Ind. Med. 52:195–201, 2009. © 2008 Wiley‐Liss, Inc.
A case of generalized argyria after ingestion of colloidal silver solution
Authors: Kim Yangho , Suh Ho Seok , Cha Hee Jeong , Kim Suk Hwan , Jeong Kyoung Sook , Kim Dong Hoon
Published: December 2008

A 58‐year‐old woman was referred to our hospital due to progressive skin darkening, which began 5 months previously. The patient had strikingly diffuse blue‐gray discoloration of the skin, most prominent in sun‐exposed areas, especially her face and hands. The oral mucosa, tongue, gums, eye conjunctiva, ears, nail beds, and trunk were also involved. Bluish‐gray discoloration of all nails was aggravated by cold weather. She had ingested 1 L of colloidal silver solution daily for approximately 16 months as a traditional remedy. Her serum silver concentration was 381 ng/ml which was a very high (reference level: <15 ng/ml). Light microscopic examination of a punch biopsy specimen from her nose revealed fine, minute, round, and brown‐black granules deposited in the basement membrane of hair follicular epithelium. Scanning electron microscopic examination showed electron‐dense granules deposited in the intercellular space of sweat glands. Energy disperse X‐ray spectrometry analysis demonstrated peaks for silver and sulfur in the dense black deposits. The ingestion of colloidal silver appears to be an increasing practice among patients using alternative health practices. All silver‐containing products including colloidal silver should be labeled with a clear warning to prevent argyria, especially in alternative health practices. Am. J. Ind. Med. 52:246–250, 2009. © 2008 Wiley‐Liss, Inc.
N,N‐diethyl dithiocarbamato group induced photografting of methyl methacrylate onto polyurethane
Authors: Bhuyan P. K. , Kakati D. K.
Published: December 2008

The N,N‐diethyl dithiocarbamato group present in a variety of compounds acts as an initiator in the photopolymerization processes. The photolability of this group is due to the cleavage of the CS bond by UV irradiation. N,N‐Diethyl dithiocarbamato‐(1,2)‐propane diol with a pendent N,N‐diethyl dithiocarbamato group was prepared from 3‐chloro‐(1,2)‐propane diol and sodium diethyl dithiocarbamate. A polyurethane macrophotoinitiator was then synthesized by a two‐step process, where N,N‐diethyl dithiocarbamato‐(1,2)‐propane diol was used as the chain extender. Other components used included 4,4′‐diphenylmethane diisocyanate and poly(propylene glycol) (molecular weight = 1000). The polyurethane thus synthesized had pendent N,N‐diethyl dithiocarbamato groups. This polyurethane macrophotoinitiator was then used to polymerize methyl methacrylate in a photochemical reactor (Compact‐LP‐MP 88) at 254 nm. The resulting graft copolymer, polyurethane‐g‐poly(methyl methacrylate), was freed from the homopolymer by a standard procedure. The graft copolymer was characterized by Fourier transform infrared spectroscopy, 1H‐NMR spectroscopy, thermogravimetric analysis, differential scanning calorimetry, solution viscometry, and scanning electron microscopy. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Dynamic mechanical analysis of ethylene–propylene–diene monomer rubber and styrene–butadiene rubber blends
Authors: Nair T. Muraleedharan , Kumaran M. G. , Unnikrishnan G. , Pillai V. B.
Published: December 2008

The effects of blend ratio, crosslinking systems, and fillers on the viscoelastic response of ethylene–propylene–diene monomer (EPDM)/styrene–butadiene rubber (SBR) blends were studied as functions of frequency, temperature, and cure systems. The storage modulus decreased with increasing SBR content. The loss modulus and loss tangent results showed that the EPDM/SBR blend vulcanizate containing 80 wt % EPDM had the highest compatibility. Among the different cure systems studied, the dicumyl peroxide cured blends exhibited the highest storage modulus. The reinforcing fillers were found to reduce the loss tangent peak height. The blend containing 40 wt % EPDM showed partial miscibility. The dispersed EPDM phase suppressed the glass‐transition temperature of the matrix phase. The dynamic mechanical response of rubbery region was dominated by SBR in the EPDM–SBR blend. The morphology of the blend was studied by means of scanning electron microscopy. The blend containing 80 wt % EPDM had small domains of SBR particles dispersed uniformly throughout the EPDM matrix, which helped to toughen the matrix and prevent crack propagation; this led to enhanced blend compatibility. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Influence of surface photocrosslinking on properties of thermoplastic starch sheets
Authors: Zhou Jiang , Ma Yunhai , Zhang Jian , Tong Jin
Published: December 2008

The surface of glycerol plasticized thermoplastic starch (TPS) sheets was modified by photocrosslinking under ultra violet (UV) irradiation. Sodium benzoate was selected as photosensitizer and induced onto sheet surface layer by soaking the sample sheets in photosensitizer aqueous solution. The effects of concentration of the photosensitizer aqueous solution, soaking time and moisture content in sheets before UV irradiation on the photocrosslinking were investigated. Water contact angle, moisture absorption, and mechanical properties were measured to characterize the influence of the surface photocrosslinking modification on the properties of TPS sheets. The obtained results showed that the surface photocrosslinking treatments markedly reduced the water sensitivity of TPS sheets and enhanced their tensile strength and Young's modulus but decreased the elongation at break. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
The effect of high pressure processing on the morphology of polyethylene films tested by differential scanning calorimetry and X‐ray diffraction and its influence on the permeability of the polymer
Authors: Yoo Seungran , Lee Jaesung , Holloman Christopher , Pascall Melvin A.
Published: December 2008

This study investigated the influence of high‐pressure processing on the morphology and permeability of low‐density polyethylene (LDPE) films used for food packaging. This was done by monitoring the crystallinity, melting temperature (Tm), and oxygen transmission rate (OTR) of the materials before and after the pressure treatments. A first set of pouches made from the LDPE films were filled with 95% ethanol then pressured at 200, 400, 600, and 800 MPa for 5 and 10 min at 25 and 75°C. The crystallinity and Tm of the films were measured using differential scanning calorimetry (DSC). X‐ray diffraction (XRD) was also used to determine the crystallinity. A second set of LDPE pouches were similarly made but a half of them were filled with 95% ethanol and the other half filled with distilled water. These second set of pouches were pressured at 200, 600, and 800 MPa then their OTR tested. Results of the DSC experiments showed that the Tm increased with increasing pressure intensity but the crystallinity changes were not detectible. The XRD method on the other hand, showed significant (P < 0.05) crystallinity increases with increasing pressure treatments. The gas permeability analyses showed decreasing OTR's with increasing high‐pressure intensity treatments. The OTR in the pouches filled with the 95% ethanol was slightly lower than that of the pouches filled with water. These findings allowed us to better anticipate the behavior of LDPE films used to package high‐pressure processed foods. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
A study on the flame‐retardance of poly(vinyl chloride) incorporated with metal hydroxystannates
Authors: Zhang Bo , Jiao Yunhong , Xu Jian Zhong
Published: December 2008

In this article some metal hydroxystannates were synthesized. It shows that the ZHS with Fe2SnO3.3H2O imparts fairly good flame retardance to the plasticized poly (vinyl chloride) (PVC). The thermal stability and flammability on heating and burning were explored by TG/DTA. Study on mechanical properties of PVC had also been performed. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Comparative study on methods of detecting research fronts using different types of citation
Authors: Shibata Naoki , Kajikawa Yuya , Takeda Yoshiyuki , Matsushima Katsumori
Published: December 2008

In this article, we performed a comparative study to investigate the performance of methods for detecting emerging research fronts. Three types of citation network, co‐citation, bibliographic coupling, and direct citation, were tested in three research domains, gallium nitride (GaN), complex network (CNW), and carbon nanotube (CNT). Three types of citation network were constructed for each research domain, and the papers in those domains were divided into clusters to detect the research front. We evaluated the performance of each type of citation network in detecting a research front by using the following measures of papers in the cluster: visibility, measured by normalized cluster size, speed, measured by average publication year, and topological relevance, measured by density. Direct citation, which could detect large and young emerging clusters earlier, shows the best performance in detecting a research front, and co‐citation shows the worst. Additionally, in direct citation networks, the clustering coefficient was the largest, which suggests that the content similarity of papers connected by direct citations is the greatest and that direct citation networks have the least risk of missing emerging research domains because core papers are included in the largest component.
Synthesis of Alginate Oligosaccharides Containing L‐Guluronic Acids
Authors: Chi Fa‐Chen , Kulkarni Suvarn S. , Zulueta Medel Manuel L. , Hung Shang‐Cheng
Published: December 2008

Making ends meet: The L‐gulopyranosyl trichloroacetimidate and 1,6‐anhydro‐2,3‐di‐O‐benzyl‐β‐L‐gulopyranose, efficiently derived from L‐ascorbic acid, were individually used as a starting unit and an elongation unit to prepare L‐guluronic acid linked alginate oligosaccharides in excellent α selectivity and in good yields.

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Power frequency magnetic fields and risk of childhood leukaemia: Misclassification of exposure from the use of the ‘distance from power line’ exposure surrogate
Authors: Maslanyj Myron , Simpson Jill , Roman Eve , Schüz Joachim
Published: December 2008

A recent study examining the relationship between distance to nearby power lines and childhood cancer risk re‐opened the debate about which exposure metrics are appropriate for power frequency magnetic field investigations. Using data from two large population‐based UK and German studies we demonstrate that distance to power lines is a comparatively poor predictor of measured residential magnetic fields. Even at proximities of 50 m or less, the positive predictive value of having a household measurement over 0.2 µT was only 19.4%. Clearly using distance from power lines, without taking account of other variables such as load, results in a poor proxy of residential magnetic field exposure. We conclude that such high levels of exposure misclassification render the findings from studies that rely on distance alone uninterpretable. Bioelectromagnetics 30:183–188, 2009. © 2008 Wiley‐Liss, Inc.
Novel Zinc Porphyrin Sensitizers for Dye‐Sensitized Solar Cells: Synthesis and Spectral, Electrochemical, and Photovoltaic Properties
Authors: Lee Cheng‐Wei , Lu Hsueh‐Pei , Lan Chi‐Ming , Huang Yi‐Lin , Liang You‐Ren , Yen Wei‐Nan , Liu Yen‐Chun , Lin You‐Shiang , Diau Eric Wei‐Guang , Yeh Chen‐Yu
Published: December 2008

Novel meso‐ or β‐derivatized porphyrins with a carboxyl group have been designed and synthesized for use as sensitizers in dye‐sensitized solar cells (DSSCs). The position and nature of a bridge connecting the porphyrin ring and carboxylic acid group show significant influences on the spectral, electrochemical, and photovoltaic properties of these sensitizers. Absorption spectra of porphyrins with a phenylethynyl bridge show that both Soret and Q bands are red‐shifted with respect to those of porphyrin 6. This phenomenon is more pronounced for porphyrins 3 and 4, which have a π‐conjugated electron‐donating group at the meso position opposite the anchoring group. Upon introduction of an ethynylene group at the meso position, the potential at the first oxidation alters only slightly whereas that for the first reduction is significantly shifted to the positive, thus indicating a decreased HOMO–LUMO gap. Quantum‐chemical (DFT) results support the spectroelectrochemical data for a delocalization of charge between the porphyrin ring and the amino group in the first oxidative state of diarylamino‐substituted porphyrin 5, which exhibits the best photovoltaic performance among all the porphyrins under investigation. From a comparison of the cell performance based on the same TiO2 films, the devices made of porphyrin 5 coadsorbed with chenodeoxycholic acid (CDCA) on TiO2 in ratios [5]/[CDCA]=1:1 and 1:2 have efficiencies of power conversion similar to that of an N3‐based DSSC, which makes this green dye a promising candidate for colorful DSSC applications.
Produktdesign disperser Stoffe: Industrielles Partikelcoating
Authors: Rähse W.
Published: December 2008

Durch das oberflächliche Überziehen von Partikeln mit einer oder mehreren Schichten lassen sich zum einen neben den mechanischen und ästhetischen Eigenschaften auch die Lagerstabilität sowie die Produktsicherheit verbessern. Zum anderen besteht die Möglichkeit, den Zeitpunkt der Auflösung und die Freisetzungskinetik über entsprechende Überzüge (meist Polymere) zu steuern. Das Aufbringen der Schicht erfolgt vorzugsweise durch das simultane Aufsprühen und Trocknen von Lösungen/Suspensionen in Wirbelschichtapparaten. Das Verfahren ist zwischen den gleichzeitig auftretenden Prozessen, Sprühtrocknung und Granulation, genau einzustellen. Industriell eingesetzt werden Coatingverfahren nicht nur für Tabletten in der Pharmaindustrie, sondern auch für Enzyme, das Beizen von Saatgut, für Langzeitdünger sowie für verschiedene chemische Stoffe (Natriumpercarbonat, Citronensäure). Das Partikelcoating stellt vielseitige Möglichkeiten zur Optimierung des Produktdesins zur Verfügung, die auch in der Chemie vermehrt genutzt werden.
Gasförmige und feste Reaktionsprodukte beim Abbrand von Indoor‐Feuerwerk
Authors: Dutschke A. , Lohrer C. , Seeger S. , Kurth L.
Published: December 2008

Beim Abbrand einzelner Feuerwerkskörper für den Indoor‐Bereich wurden als gasförmige Hauptreaktionsprodukte unter anderem CO2, CO, COS, nitrose Gase, diverse Kohlenwasserstoffe und Schwefelverbindungen (teilweise in sehr hohen Konzentrationen) mit Hilfe der FTIR‐Spektroskopie nachgewiesen. Zusätzliche Feinstaubmessungen parallel zum Abbrand in einem großen Raum illustrierten die zeitweise hohen Partikelkonzentrationen an unterschiedlichen Messpunkten.
Umwandlung diskontinuierlicher chemischer Prozesse in eine kontinuierliche Prozessführung unter Verwendung mikrostrukturierter Reaktoren – Reaktionstechnik und Sicherheit
Authors: Hugo P. , Lopez F.
Published: December 2008

Reaktions‐ und sicherheitstechnische Aspekte der Umwandlung eines diskontinuierlichen chemischen Prozesses in ein kontinuierliches Verfahren unter Verwendung von Mikroreaktoren werden untersucht. Ausgangspunkt ist der diskontinuierliche Prozess mit seiner Produktqualität, die bei der Umwandlung erhalten bleiben soll. Geeignet für eine Umwandlung sind besonders schnelle, stark exotherme, homogene Flüssigphase‐Reaktionen. Die thermisch sichere Auslegung von Mikroreaktoren hängt von der Geschwindigkeit der Reaktion ab und wird für zwei Grenzfälle behandelt. Als Anwendungsbeispiel wird eine technisch durchgeführte Fluorierungsreaktion vorgestellt.
Produktdesign disperser Stoffe: Industrielle Granulation
Authors: Rähse W.
Published: December 2008

Die Herstellung von Granulaten aus pulverförmigen Feststoffen unter Flüssigkeitszusatz mit anschließender Trocknung/Kühlung ist in der Industrie weltweit bei Dünge‐, Wasch‐ und Reinigungsmitteln, bei Eisenerzpellets und Blähton (Bauhilfsstoff) sowie als Vorstufe der Tablettierung von therapeutischen Stoffen etabliert. Mit der Nassgranulation lassen sich die Pulver im Produktdesign verbessern. Im Vergleich zu den Primärteilchen sind die erzeugten Granulate größer, runder, stabiler und fließfähiger. Aus den Unterschieden in den Korngrößenverteilungen der Primärteilchen (sehr breit/mono‐ und bimodal oder sehr eng) lassen sich drei Granulationstypen ableiten, die sich in der Granulationsdauer unterscheiden. Diese wird über das Durchmesserverhältnis der agglomerierenden Teilchen bestimmt. Feine Teilchen haften im Gegensatz zu großen Partikeln sofort fest am groben Kernmaterial. In Agglomeraten aus gleich großen Teilchen lösen sich immer wieder Flüssigkeitsbrücken und bilden sich neu, bis stabile Agglomerate entstehen. Das Scale‐up für die Granulation in horizontalen Mischern beruht auf gleichen Mischertypen, der geometrischen Ähnlichkeit und auf identischen Froude‐Zahlen. Alle Betriebsbedingungen sind vergleichbar einzustellen. Ein repräsentatives Produktmuster erfordert drei Granulationen hintereinander, wobei die zweite und dritte Charge unter Zusatz der gemahlenen Über‐ und Unterkornanteile sowie der Filterstäube durchzuführen ist. Das Produktdesign lässt sich über die Prozessführung beeinflussen.
Probabilistische Methoden in der Anlagensicherheit und ihr Anwendungspotenzial
Authors: Hauptmanns U.
Published: December 2008

Ein Überblick über die Vorgehensweise bei probabilistischen Analysen verschiedenen Umfangs und Tiefe wird gegeben. Mögliche Anwendungsfelder werden aufgezeigt und einige technische Verbesserungen aufgrund von Analyseergebnissen mitgeteilt.
Eine Methode zur Abschätzung des Risikos verfahrenstechnischer Anlagen unter Berücksichtigung technischer, organisatorischer und managementspezifischer Aspekte
Authors: Acikalin A.
Published: December 2008

Die Ursache schwerer Unfälle in der Vergangenheit ist oftmals auf Organisations‐ und Managementprobleme zurückzuführen. Umso mehr gilt es, diese Aspekte in Risikobetrachtungen zu integrieren. Der Schwerpunkt von Risikobetrachtungen lag in der Vergangenheit allerdings auf den technischen Aspekten, organisatorischen und managementspezifischen Faktoren wurde weniger Beachtung geschenkt. Die Erkenntnis, dass derartige Probleme durch die Einführung und gewissenhafte Anwendung eines Sicherheitsmanagementsystems (SMS) vermindert werden können, ermöglicht über die Leistungsfähigkeit des SMS den Zugang zu einer ganzheitlichen Risikobetrachtung unter Berücksichtigung technischer, organisatorischer und managementspezifischer Aspekte. In diesem Beitrag wird hierzu eine computerbasierte Methode vorgestellt. Mit Hilfe dieser Methode kann die Leistungsfähigkeit des SMS bewertet und in die Risikobetrachtung integriert werden. Darüber hinaus lassen sich Defizite im SMS erkennen und kritische Managemententscheidungen identifizieren und somit Lücken im Konzept zur Verhinderung von Störfällen (KVS) erkennen und der Anlagenbetrieb sicher gestalten.
Gemeinsame Sicherheitsphilosophie im Chemiepark Marl
Authors: Kaßmann Klaus‐Dieter , Mallmann Thomas , Hellhammer Jörg
Published: December 2008

Um in einem Chemiepark einen hohen Sicherheitsstandard zu garantieren, bedarf es der verschiedensten Elemente wie z. B. Vertrags‐ und Regelwerke in dem relevante Strukturen für die Zusammenarbeit festgelegt werden. Des Weiteren ist eine Standortbetreibergesellschaft unerlässlich, die die Organisationsstruktur unterhält, in der alle erforderlichen Handlungs‐ und Entscheidungsprozesse sowie Funktionen bis hin zum Standortleiter abgebildet sind. Die Standortbetreibergesellschaft stellt die notwendigen Fachleute und unterhält die gemeinsamen Ausschüsse, in denen die an einem Chemiepark befindlichen Gesellschaften die bezüglich Umwelt, Gesundheit und Sicherheit für alle geltenden Standards festlegen.
Explosionsgrenzen bei nichtatmosphärischen Bedingungen
Authors: Brandes E. , Schröder V.
Published: December 2008

Die Kenntnisse der Einflüsse von Druck, Temperatur und Oxidationsmittel auf sicherheitstechnische Kenngrößen wie Explosionsgrenzen sind eine notwendige Voraussetzung, um zu entscheiden, ob mit den bei atmosphärischen Bedingungen geltenden Kenngrößen eine ausreichende Sicherheit zu gewährleisten ist. Dies wird anhand von Beispielen erklärt und die Konsequenzen für die praktische Anwendung in der Industrie diskutiert.
Anlagensicherheit „made in Germany”︁ – sichern wir unsere Kompetenz
Authors: Muschelknautz S. , Schönbucher A. , Pfeil N.
Published: December 2008

Bisher ist das Sicherheitsniveau verfahrenstechnischer Anlagen in Deutschland hoch. Die Anzahl der Institute, die auf dem Gebiet der technischen Sicherheit forschen und damit zum Kompetenzerhalt beitragen, geht kontinuierlich zurück. Dies liegt zum einen an der aktuellen Forschungspolitik, zum anderen daran, dass die „neuen”︁ Themen wie Life Sciences, Nano‐, Umwelt‐ oder Informations‐ und Kommunikationstechnologien insbesondere für junge Menschen, die gerade dabei sind, sich beruflich auszurichten, eine hohe Attraktivität besitzen. Der Staat und die Wirtschaft sind aufgerufen gemeinsam etwas dagegen tun.
CHEMSAFE – Eine Datenbank für bewertete sicherheitstechnische Kenngrößen
Authors: Molnarne M. , Möller W.
Published: December 2008

Sicherheitstechnische Kenngrößen bilden die Grundlage des Brand‐ und Explosionsschutzes. Sie müssen daher stets auf dem neuesten Stand, verlässlich und schnell verfügbar sein. Diese Anforderungen erfüllt die Datenbank CHEMSAFE, ein Gemeinschaftsprojekt der Bundesanstalt für Materialforschung und ‐prüfung (BAM), der Physikalisch‐Technischen Bundesanstalt (PTB) und der DECHEMA Gesellschaft für Chemische Technik und Biotechnologie e. V. Die Datenbank enthält von Fachleuten bewertete Kenngrößen von etwa 3000 brennbaren Flüssigkeiten, Gasen und Stäuben sowie von etwa 2800 Gemischen.
Zündung von Acetylen durch Druckstoß in Rohrleitungen
Authors: Schröder V. , Holtappels K.
Published: December 2008

In der Prozesstechnik kommt es immer wieder zu Zündungen durch Druckstöße mit Gasen. Bekannt ist dieses Phänomen vom Umgang mit Sauerstoff im Kontakt mit nicht geeigneten Materialien. Aber auch andere Gase, z. B. Acetylen, können durch schnelle Kompression gezündet werden. In der vorliegenden Arbeit werden, in Fortführung früherer Untersuchungen in Rohren, solche Zündvorgänge mit Hilfe von Zündtemperaturen abgeschätzt.
Quantitative Risikoanalyse (QRA) – Anwendungsbeispiele aus dem Großanlagenbau
Authors: Rath S. , Can Ü. , Leimer E.
Published: December 2008

Der Beitrag gibt einen Überblick über die Durchführung von quantitativen Risikoanalysen (QRA), wie sie häufig im internationalen Anlagenbau der Öl‐ und Gasindustrie angewendet werden. Anhand von zwei Beispielen der Öl‐ und Gasindustrie wird dargestellt, wie die Modellierung erfolgt und anlagenspezifische Parameter einfließen. Die beiden Beispiele zeigen, dass quantitative Risikoanalysen einen wesentlichen Beitrag zu designrelevanten Entscheidungen leisten können und nicht nur zum übergeordneten Nachweis der Einhaltung von vorgegebenen Akzeptanzkriterien dienen.
Von der Daumenregel zur dynamischen Simulation – Auslegung von Sicherheitsventilen für chemische Reaktoren
Authors: Christ M. , Westphal F.
Published: December 2008

Die Vorgehensweise bei der Auslegung von Sicherheitsventilen für durchgehende Reaktionen wird in diesem Beitrag beschrieben. Dazu sind detaillierte Kenntnisse über die Reaktion erforderlich und es müssen Annahmen über den Aufwallvorgang des Reaktionsgemisches getroffen werden, der durch das Öffnen des Sicherheitsventils ausgelöst wird, um die möglicherweise auftretende Zweiphasenströmung aus Gas und mitgerissener Flüssigkeit berechnen zu können. Eine vorsorgliche Überdimensionierung für nachgeschaltete Rohrleitungen und Rückhaltesysteme kann zu erheblichen Mehrkosten führen. Beim Einsatz von Berstscheiben oder Vollhub‐Sicherheitsventilen kann durch den unnötig großen abströmenden Mengenstrom eine Zweiphasenströmung mit einem Austrag von Flüssigkeit aus dem Reaktor provoziert werden. Aus wissenschaftlicher Sicht gibt es bis heute keine allgemeingültige Methode, mit der der Entlastungsvorgang bei einer durchgehenden chemischen Reaktion zuverlässig berechnet werden kann. Einige häufig angewendete Auslegungsmethoden – FIA‐Nomogramm, DIERS‐ω‐Methode, „Churn‐Turbulent”︁‐Aufwallmodell, „Simple”︁‐Method, ISO/DIS 4126‐Methode – werden hier miteinander verglichen und bewertet.
Risk of Heart Failure Due to a Combination of Mild Mitral Regurgitation and Impaired Distensibility of the Left Ventricle in Patients with Old Myocardial Infarction
Authors: Inami Shu , Matsuda Ryuko , Toyoda Shigeru , Hata Yoshihito , Taguchi Isao , Abe Shichiro
Published: December 2008

Background

Ischemic mitral regurgitation (MR) is a serious complication after myocardial infarction, and the incidence of heart failure (HF) increases as the severity of MR increases. However, little is known about the relationship between mild MR and HF in the patients with old myocardial infarction (OMI) and a normal ejection fraction (EF).

Hypothesis

We hypothesized that a combination of mild MR and impaired distensibility of the left ventricle may increase the risk of diastolic HF in the patients with OMI and a normal EF.

Methods

The relationship between HF and mild MR was retrospectively investigated in 62 patients with OMI and EF of > 50% on echocardiography.

Results

Of the 62 patients, 47 (76%) did not have HF and 15 (24%) had HF. There was a significant difference in the incidence of mild MR between the patients with and without HF (p < 0.0001): of the 47 patients without HF, mild MR was detected in 19, but all 15 patients with HF had mild MR. However, there were no significant differences in age, gender, infarct sites, diseased coronary vessels, peak CK level, and observation period between the 2 groups. An increased E‐wave and the ratio of the E‐wave to the A‐wave (E/A), a reduction of the E‐wave deceleration time, and an increased brain natriuretic peptide (BNP) level were significantly noted in HF patients with mild MR compared with patients without HF.

Conclusions

Even a mild MR may cause diastolic HF in patients with impaired distensibility of the left ventricle due to ischemic heart disease. Copyright © 2008 Wiley Periodicals, Inc.
Effects of Levosimendan on Left Atrial Functions in Patients with Ischemic Heart Failure
Authors: Duygu Hamza , Nalbantgil Sanem , Ozerkan Filiz , Zoghi Mehdi , Akilli Azem , Erturk Umit , Akin Mustafa , Nazli Cem , Ergene Oktay
Published: December 2008

Background

With further progression of left ventricular (LV) dysfunction, the left atrial (LA) contribution to LV filling gradually decreases, and LA dysfunction deteriorates the decreased LV filling in patients with heart failure (HF).

Hypothesis

This study sought to investigate the effects of levosimendan on LA function in patients with HF.

Methods

A total of 60 patients having acute decompensated HF with ischemic cardiomyopathy and LV ejection fraction (LVEF) < 40% were included in the study. Patients were randomized to levosimendan (n = 30) or to dobutamine (n = 30). Before and 24 h after treatment, LVEF, mitral inflow peak E and A wave velocity, E/A ratio, mitral lateral annulus peak Em wave velocity, E/Em ratio, LA volumes, and from the LA volumes the active emptying fraction (AEF), passive emptying fraction (PEF), and reservoir fraction (RF) were measured.

Results

All LA volumes were significantly reduced after levosimendan administration, but in the dobutamine group only minimal volume (Vmin) was reduced. Although AEF increased in both groups, the improvement of AEF was greater in the levosimendan group than in the dobutamine group (14% ± 9% versus 2% ± 1%, p = 0.001). The PEF (12% ± 8% versus 21% ± 6%, p = 0.04) and RF (23% ± 4% versus 38% ± 3%, p = 0.001) significantly increased after levosimendan administration, whereas these parameters did not change after dobutamine. In patients receiving levosimendan, there was a significant, positive correlation between PEF and Em (r = 0.475, p = 0.008), and there were significant negative correlations between PEF and E/Em (r = − 0.491, p = 0.006), and AEF and E/Em (r = − 0.654, p = 0.001).

Conclusions

Left atrial functions respond better to levosimendan than to dobutamine in decompensated HF. Copyright © 2008 Wiley Periodicals, Inc.
Management of Coronary Artery Disease in Patients Undergoing Elective Abdominal Aortic Aneurysm Open Repair
Authors: Hosokawa Yusuke , Takano Hitoshi , Aoki Asako , Inami Toru , Ogano Michio , Kobayashi Nobuaki , Tanabe Jun , Yokoyama Hiroyuki , Kato Takayoshi , Takagi Hisato , Umemoto Takuya , Takayama Morimasa , Mizuno Kyoichi
Published: December 2008

Background

The efficacy of prophylactic coronary revascularization with percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG) surgery in patients with abdominal aortic aneurysm (AAA) scheduled for open repair surgery remains controversial.

Hypothesis

Concomitant coronary artery disease (CAD) with no inducible ischemia can be medically treated in AAA patients undergoing open repair as long as the existence of CAD is recognized.

Method

A retrospective analysis of acute and long‐term outcomes was performed for 122 patients with AAA who underwent coronary arteriography (CAG) for preoperative evaluation followed by elective open repair.

Results

Preoperative CAG revealed no CAD in 54 patients (non‐CAD group) and the existence of CAD in 68 patients. Prophylactic PCI or CABG surgery was performed in 16 patients (CAD‐PCI/CABG group) with symptomatic angina, ischemia proven by pharmacological stress scintigraphy, or coexistence of reduced cardiac contraction and coronary stenosis in multiple vessels. Medical treatment was administered to 52 patients who had no signs of ischemia (CAD‐medical group). During the perioperative period, no cardiac event occurred irrespective of the existence of CAD. The long‐term outcomes in the CAD‐medical group were equivalent to those in the non‐CAD group. In the CAD‐PCI/CABG group, the cardiac event‐free rate was comparable with that of other groups, although mortality was higher.

Conclusion

In patients undergoing AAA open repair, medical treatment for concomitant CAD with no obvious inducible ischemia does not confer unfavorable outcomes. Although prophylactic coronary revascularization possibly prevents future cardiac events, it appears to be necessary in a very limited number of cases. Copyright © 2008 Wiley Periodicals, Inc.
B‐type Natruiretic Peptide Levels Stratify the Risk for Arrhythmia Among Implantable Cardioverter Defibrillator Patients
Authors: Galante Ori , Amit Guy , Zahger Doron , Wagshal Abraham , Ilia Reuben , Katz Amos
Published: December 2008

Background

We sought to study the association between brain natriuretic peptide (BNP) levels and the occurrence of ventricular arrhythmias in patients with left ventricular dysfunction (LVD) and an implantable cardioverter defibrillator (ICD).

Methods

This was a prospective study of consecutive, stable, ambulatory patients with moderate and severe ischemic LVD and an ICD. A plasma BNP level was obtained at recruitment. Patients were evaluated every 3–6 mo for a minimum of 1 y. The primary end point was the occurrence of malignant ventricular arrhythmia or sudden cardiac death (SCD).

Results

The cohort consisted of 94 subjects (6 women) with a mean ± standard deviation (SD) age of 69 ± 10 y. The ICD implantation indication was primary and secondary prevention of SCD in 49% and 51% of subjects, respectively. A primary end point occurred in 27 patients (29%), and was more frequent in symptomatic heart failure patients and those implanted for secondary prevention of SCD. The median BNP level was significantly higher among patients who experienced an end point (191 pg/ml versus 142 pg/ml, p = 0.03). After controlling for New York Heart Association heart failure class and ICD implantation indication, the odds ratio (OR) for experiencing an adverse outcome among the upper BNP quartile versus all others was 3.5 (95% confidence interval [CI]: 1.2–10.2). Among patients implanted for primary prevention of SCD, none of the patients in the lower BNP quartile (BNP < 91 pg/ml) experienced an adverse outcome.

Conclusions

These results suggest that abnormally high BNP levels not only predict cardiac death, but also arrhythmic death in this patient population, and a low BNP level can serve to identify low risk patients. Copyright © 2008 Wiley Periodicals, Inc.
Evaluation of Rosiglitazone Administration on Cardiovascular Function in Severe Obesity
Authors: Brunani Amelia , Liuzzi Antonio , Titon AnnaMaria , Graci Salvatore , Castagna Giovanna , Viberti Gian Carlo , Gondoni Luca A.
Published: December 2008

Background

Obese patients have myocardial structural and functional alterations related to insulin resistance.

Hypothesis

The purpose of the study was to analyze the effects of rosiglitazone, an insulin sensitizer agent, on cardiac morphometry and functioning.

Methods

In 2 groups of sex‐ and age‐matched, nondiabetic, obese patients (5 men and 7 women, age 19–51 y; group A: body mass index [BMI] 40.6 ± 3.4 kg/m2; group B: BMI 42.6 ± 2.7 kg/m2), we evaluated the basal insulin sensitivity index (HOMA[IS]), body composition by bioelectrical impedance analysis and 24‐h blood pressure monitoring. Furthermore, all patients underwent conventional 2‐Dimensional and color Doppler echocardiography, and pulsed‐wave tissue Doppler imaging (TDI). After the baseline evaluation, all patients were put on a hypocaloric diet (70% basal metabolic rate) plus placebo if they were in group A, or plus rosiglitazone (4 mg twice daily; Avandia [GlaxoSmithKline plc., Brentford, Middlesex, United Kingdom]) if they were in group B, for 6 mo.

Results

Significant decreases in body weight, total fat mass, BMI, and systolic blood pressure were registered in both groups. Rosiglitazone administration appeared more efficient in improving HOMA(IS) (mean difference: 0.30 ± 0.19 versus 0.11 ± 0.21, p < 0.05). Left ventricular (LV) diastolic diameter (49.4 ± 7.7 versus 52.3 ± 5.4 mm, p < 0.05) and E wave (0.89 ± 0.18 versus 0.99 ± 0.20 m/sec, p < 0.05) increased in the rosiglitazone group due to a rise in preload and water content without peripheral edema. The increase in systolic (Sa) wave velocity in both groups was probably a result of the general improvement in insulin metabolism and the decrease in blood pressure.

Conclusions

We confirmed the positive effect of rosiglitazone on glucose metabolism in obese, nondiabetic patients, but changes in insulin sensitivity did not explain the cardiac effects produced by further mechanisms. Copyright © 2008 Wiley Periodicals, Inc.
Left Ventricular Dyssynchrony in Hypertensive Patients Without Congestive Heart Failure
Authors: Yang Benjamin , Chettiveettil Dennis , Jones Fermon , Aguero Millan , Lewis Jannet F.
Published: December 2008

Background

Normal left ventricular (LV) systolic function is present in as many as 50% of patients with congestive heart failure. The majority of such patients have systemic hypertension. Recent studies have demonstrated LV dyssynchrony among patients with heart failure and normal systolic function. However, it is unclear whether such abnormalities exist in hypertensive patients who have not developed clinical evidence of heart failure.

Methods

Hospitalized patients with established hypertension undergoing echocardiography who met the following criteria were eligible for the study: LV ejection fraction (EF) ≥ 50%, wall ≥11 mm, absence of valvular or known ischemic disease, and normal QRS duration. Complete 2‐Dimensional and Doppler echocardiography studies with tissue Doppler imaging (TDI) were performed in all patients. Dyssynchrony was measured using time from QRS to peak systolic velocity on TDI (T‐P) in 3 apical views. Normal values for dyssynchrony were established in a group of normotensive patients with normal echocardiography studies.

Results

The study included 42 patients (19 women, 23 men with a, mean age of 59.6 y (range 32–96 y). Left ventricular dyssynchrony was common, occurring in 20 of 42 patients (47.6%). Dyssynchrony assessed with the maximum T‐P (T‐Pmax) was significantly related to LV mass (r = 0.32, p = 0.036), left atrial volume (r = 0.59, p < 0.0001), and LV sphericity index (0.32, p = 0.037). Dyssynchrony was not related to age or LV filling pressure calculated from the Doppler study.

Conclusions

Left ventricular dyssynchrony is common among hypertensive patients with normal LV systolic function and no evidence of congestive heart failure. The severity of LV dyssynchrony is related to the magnitude of LV hypertrophy, left atrial size, and LV remodeling. Copyright © 2008 Wiley Periodicals, Inc.
A Prior Myocardial Infarction: How Does it Affect Management and Outcomes in Recurrent Acute Coronary Syndromes?
Authors: Motivala Apurva A. , Tamhane Umesh , Ramanath Vijay S. , Saab Fadi , Montgomery Daniel G. , Fang Jianming , Kline‐Rogers Eva , May Niquole , Ng Garry , Froehlich James , Gurm Hitinder , Eagle Kim A.
Published: December 2008

Background

Despite improved secondary prevention efforts, acute coronary syndrome (ACS) recurrence among patients with prior history of coronary events remains high. The differences in presentation, management, and subsequent clinical outcomes in patients with and without a prior myocardial infarction (MI) and presenting with another episode of ACS remain unexplored.

Methods

A total of 3,624 consecutive patients admitted to the University of Michigan with ACS from January 1999 to June 2006 were studied retrospectively. In‐hospital management, outcomes, and postdischarge outcomes such as death, stroke, and reinfarction in patients with and without a prior MI were compared.

Results

Patients with a prior MI were more likely to be older and have a higher incidence of diabetes mellitus, hypertension, hyperlipidemia, and peripheral vascular disease. In‐hospital outcomes were not significantly different in the 2 groups, except for a higher incidence of cardiac arrest (4.3% versus 2.5%, p < 0.01) and cardiogenic shock (5.7% versus 3.9%, p = 0.01) among patients without a prior MI. However, at 6 mo postdischarge, the incidences of death (8.0% versus 4.5%, p < 0.0001) and recurrent MI (10.0% versus 5.1%, p < 0.0001) were significantly higher in patients with a prior history of MI compared with those without.

Conclusion

Patients with prior MI with recurrent ACS remain at a higher risk of major adverse events on follow‐up. This may be partly explained by the patients not being on optimal medications at presentation, as well as disease progression. Increased efforts must be directed at prevention of recurrent ACS, as well as further risk stratification of these patients to improve their overall outcomes. Copyright © 2008 Wiley Periodicals, Inc.
Biomarkers on Admission for the Prediction of Cardiovascular Events After Primary Stenting in Patients with ST‐Elevation Myocardial Infarction
Authors: Jeong Young‐Hoon , Lee Seung‐Whan , Lee Cheol Whan , Hong Myeong‐Ki , Kim Jae‐Joong , Park Seong‐Wook , Park Seung‐Jung , Park Duk‐Woo , Kim Young‐Hak
Published: December 2008

Background

Several cardiac biomarkers have been shown to have predictive values for the development of cardiovascular disease and clinical outcome after events, and are now broadly used by clinicians. Little is known about the utility of these biomarker values on admission in ST‐elevation myocardial infarction (STEMI) cases of primary drug‐eluting stent (DES) implantation and intense medical therapy.

Hypothesis

Because little is known about the utility of these biomarkers on admission in ST‐elevation myocardial infarction (STEMI) in cases primary drug‐eluting stent (DES) implantation and intense medical therapy, we evaluated clinical outcomes.

Methods

We enrolled 207 consecutive STEMI patients treated with primary stenting (mean age, 57.3 ± 12.0 y). We evaluated the association between B‐type natriuretic peptide (BNP), cardiac troponin I (cTnI), high‐sensitivity C‐reactive protein (hs‐CRP) on admission, and death, reinfarction, and new or worsening congestive heart failure (CHF) through 1 y.

Results

In backward‐elimination models including all biomarkers, only the cTnI level was retained as a predictor of 1‐y CHF (odds ratio [OR]: 1.017, 95% confidence interval [CI]: 1.001–1.034, p = 0.039). There were no predictors in terms of 1‐y death, reinfarction, and composite endpoint. When we applied a simple score system, in which patients were categorized on the basis of the number of elevated biomarkers, the 1‐y risks of death (p = 0.600), reinfarction (p = 0.185), and composite endpoint (p = 0.620) did not increase in proportion to the number of elevated biomarkers on admission. One‐y CHF only tended to increase according to the number of elevated biomarkers (p = 0.067).

Conclusions

The use of cardiac biomarkers on admission, in each or in combination, had only a minimal impact for the prediction of long‐term cardiovascular events after primary stenting in STEMI patients. Copyright © 2008 Wiley Periodicals, Inc.
With Personal and Professional Gratitude: An Editor's Thank You to J. Willis Hurst
Authors: Conti C. Richard
Published: December 2008

This editorial is about a friend who I met years ago when I had to debate him at an American College of Cardiology (ACC) meeting, and we have known and respected each other ever since. As always, he was a gentleman in that debate, and he has remained so for as long as I have known him. Education of his colleagues, teaching of medical students, residents, and fellows‐in‐training has been J. Willis Hurst's lifelong passion, and he will continue to do that until January 1st, 2009, when he retires from Emory University. Copyright © 2008 Wiley Periodicals, Inc.
Endovascular stents: Preliminary clinical results and future developments
Authors: De Jaegere Peter P. T. , De Feyter Pim J. , Van Der Giessen Willem J. , Serruys Patrick W.
Published: December 2008

At present, there is an exponential use of new interventional techniques whose proper role and value have not yet been defined. The intracoronary stent is just one example. There is no doubt that stents can be implanted with a high technical success rate associated with highly predictable immediate angiographic results and that they appear to be superior to all other interventional techniques. However, the intrinsic thrombogenicity of all devices currently available for clinical use warrants a vigorous anticoagulation, exposing the patient either to the risk of (sub) acute stent thrombosis or to the risk of hemorrhage and vascular complications. It remains to be determined whether stent implantation will reduce the incidence of restenosis and whether this results in an improved long‐term event and symptom‐free survival. Experimental studies indicate that the thrombogenic nature of stents may be controlled by coating the struts with endothelial cells or polymers. With respect to restenosis, it is evident that as long as mechanical injury is applied to the vessel wall, the vessel wall will respond with neointimal thickening. The intracoronary stent has the potential to control this tissue response by serving as a carrier for local antiproliferative drug delivery or eventually for genetic manipulation. The intensive research which is now going on in combination with experimental animal data, human postmortem pathologic observations, and angiographic studies is yielding clear insights and future directions to address these issues.