bluuebunny/crossref_metadata_2025 huggingface dataset:
Prognostic Factors for Survival After Salvage Reirradiation of Head and Neck Cancer
Authors: Tanvetyanon Tawee , Padhya Tapan , McCaffrey Judith , Zhu Weiwei , Boulware David , DeConti Ronald , Trotti Andrea
Published: March 2009

Purpose

Patients who develop recurrent or new primary head and neck cancer in a previously irradiated site have poor prognosis. Reirradiation is a treatment option, although it is associated with substantial toxicities. We investigated potential prognostic factors, including comorbidity and pre-existing organ dysfunction, for survival after reirradiation.

Methods

Institutional electronic records of patients treated with reirradiation between January 1998 and 2008 were reviewed. Comorbidity was assessed by Charlson index and Adult Comorbidity Evaluation-27 (ACE-27) grading. Organ dysfunction was defined as feeding tube dependency, functioning tracheostomy, or soft tissue defect.

Results

There were 103 patients, including 46 patients who underwent salvage surgery before reirradiation. Median progression-free and overall survivals were 12.1 months (95% CI, 9.7 to 16.6) and 19.3 months (95% CI, 13.9 to 29.9), respectively. Significant comorbidity was present in 36% of patients by Charlson index and 24% by ACE-27. Baseline organ dysfunction was present in 37% of patients. Median overall survivals were 5.5 months among those with both organ dysfunction and comorbidity per Charlson index, and 4.9 months per ACE-27, compared with 59.6 and 44.2 months, respectively, among the patients with neither organ dysfunction nor comorbidity (P < .001 and < .001). Other independent prognostic factors were interval from previous radiation, recurrent tumor stage, tumor bulk at reirradiation, and reirradiation dose. A nomogram to predict the probability of death within 24 months after reirradiation was developed (concordance index = 0.75).

Conclusion

Comorbidity and pre-existing organ dysfunction are among several important prognostic factors for patients undergoing reirradiation. For those with both comorbidity and organ dysfunction, reirradiation largely serves as a palliative therapy.
High-Risk Populations Identified in Childhood Cancer Survivor Study Investigations: Implications for Risk-Based Surveillance
Authors: Hudson Melissa M. , Mulrooney Daniel A. , Bowers Daniel C. , Sklar Charles A. , Green Daniel M. , Donaldson Sarah S. , Oeffinger Kevin C. , Neglia Joseph P. , Meadows Anna T. , Robison Leslie L.
Published: March 2009

Childhood cancer survivors often experience complications related to cancer and its treatment that may adversely affect quality of life and increase the risk of premature death. The purpose of this manuscript is to review how data derived from Childhood Cancer Survivor Study (CCSS) investigations have facilitated identification of childhood cancer survivor populations at high risk for specific organ toxicity and secondary carcinogenesis and how this has informed clinical screening practices. Articles previously published that used the resource of the CCSS to identify risk factors for specific organ toxicity and subsequent cancers were reviewed and results summarized. CCSS investigations have characterized specific groups to be at highest risk of morbidity related to endocrine and reproductive dysfunction, pulmonary toxicity, cerebrovascular injury, neurologic and neurosensory sequelae, and subsequent neoplasms. Factors influencing risk for specific outcomes related to the individual survivor (eg, sex, race/ethnicity, age at diagnosis, attained age), sociodemographic status (eg, education, household income, health insurance) and cancer history (eg, diagnosis, treatment, time from diagnosis) have been consistently identified. These CCSS investigations that clarify risk for treatment complications related to specific treatment modalities, cumulative dose exposures, and sociodemographic factors identify profiles of survivors at high risk for cancer-related morbidity who deserve heightened surveillance to optimize outcomes after treatment for childhood cancer.
Canny Resemblance
Authors: Abell Catharine
Published: March 2009

Depiction is the form of representation distinctive of figurative paintings, drawings, and photographs. Accounts of depiction attempt to specify the relation something must bear to an object in order to depict it. Resemblance accounts hold that the notion of resemblance is necessary to the specification of this relation. Several difficulties with such analyses have led many philosophers to reject the possibility of an adequate resemblance account of depiction. This essay outlines these difficulties and argues that current resemblance accounts succumb to them. It then develops an alternative resemblance account, drawing on Grice's account of nonnatural meaning and its role in determining sentence meaning to argue that something depicts an object if it bears intention-based resemblances to the object that jointly capture its overall appearance. In addition to solving the metaphysical problem of what it is for something to depict an object, this account also sheds significant light on the epistemological issue of how we are able to work out that something depicts an object. This essay argues that our ability to work out that something depicts an object results from both our more general ability to identify intentions from the products of communicative behavior and our knowledge of stylistic conventions. This account avoids the difficulties that face rival attempts to analyze depiction in terms of resemblance. It also clarifies and explains the features that distinguish depictive from nondepictive representation.
Editorial Notes
Authors: Sambamurthy Vallabh
Published: March 2009

New appointments to the editorial board are discussed in this issue.
On a Data-Driven Method for Staffing Large Call Centers
Authors: Bassamboo Achal , Zeevi Assaf
Published: March 2009

We consider a call center model with multiple customer classes and multiple server pools. Calls arrive randomly over time, and the instantaneous arrival rates are allowed to vary both temporally and stochastically in an arbitrary manner. The objective is to minimize the sum of personnel costs and expected abandonment penalties by selecting an appropriate staffing level for each server pool. We propose a simple and computationally tractable method for solving this problem that requires as input only a few system parameters and historical call arrival data for each customer class; in this sense the method is said to be data-driven. The efficacy of the proposed method is illustrated via numerical examples. An asymptotic analysis establishes that the prescribed staffing levels achieve near-optimal performance and characterizes the magnitude of the optimality gap.
Uncertain Linear Programs: Extended Affinely Adjustable Robust Counterparts
Authors: Chen Xin , Zhang Yuhan
Published: March 2009

In this paper, we introduce the extended affinely adjustable robust counterpart to modeling and solving multistage uncertain linear programs with fixed recourse. Our approach first reparameterizes the primitive uncertainties and then applies the affinely adjustable robust counterpart proposed in the literature, in which recourse decisions are restricted to be linear in terms of the primitive uncertainties. We propose a special case of the extended affinely adjustable robust counterpart—the splitting-based extended affinely adjustable robust counterpart—and illustrate both theoretically and computationally that the potential of the affinely adjustable robust counterpart method is well beyond the one presented in the literature. Similar to the affinely adjustable robust counterpart, our approach ends up with deterministic optimization formulations that are tractable and scalable to multistage problems.
OR Practice—Implementing Seasonal Logistics Tactics for Finished Goods Distribution at Deere & Company's C&CE Division
Authors: Tardif Valerie , Tayur Sridhar , Reardon James , Stines Reid , Zimmerman Pete
Published: March 2009

In 2004, Deere & Company's Commercial & Consumer Equipment Division (C&CE) engaged in a new logistics initiative to further enhance its outbound distribution network. The goal was to offer faster and more reliable replenishment to 2,500 North American independent dealers while keeping logistics costs in check by deploying different tactics during the peak (February–July) and offpeak (August–January) selling and shipping seasons. Deere and SmartOps worked together under a shared reward contract based on actual cost reductions accomplished (that are additive over the benefits that may have accrued for other reasons). Through careful analysis, validation, and verification of the data available, the team was able to develop detailed models of the current and alternative distribution systems. By formulating the key replenishment and transportation decisions and constraints as a mixed-integer mathematical program, the team was able to use powerful off-the-shelf solution software to find improvements. The ability to fix variables to perform what-if analysis also helped in the acceptance of the recommendations. Over a period of three years, Deere significantly improved service to 82% of their dealers (without any reduction in service to the other 18%) while reducing logistics costs by over $10 million. The novelty of this work stems from the dynamic seasonal optimization of Deere C&CE distribution network and replenishment decisions as a way of meeting service and cost reduction mandates, the creative use of tactical network optimization operations research models and what-if analysis to meet the implementation goals under time constraints and in the scrutiny given to the results.
Diphenylhydantoin Inhibits Osteoclast Differentiation and Function Through Suppression of NFATc1 Signaling
Authors: Koide Masanori , Kinugawa Saya , Ninomiya Tadashi , Mizoguchi Toshihide , Yamashita Teruhito , Maeda Kazuhiro , Yasuda Hisataka , Kobayashi Yasuhiro , Nakamura Hiroaki , Takahashi Naoyuki , Udagawa Nobuyuki
Published: March 2009

Diphenylhydantoin (DPH) is widely used as an anticonvulsant drug. We examined the effects of DPH on osteoclast differentiation and function using in vivo and in vitro assay systems. Transgenic mice overexpressing a soluble form of RANKL (RANKL Tg) exhibited increased osteoclastic bone resorption. Injection of DPH into the subcutaneous tissue overlying calvaria of RANKL Tg mice suppressed the enhanced resorption in the calvaria. In co-cultures of mouse osteoblasts and bone marrow cells, DPH inhibited lipopolysaccharide (LPS)-induced osteoclast formation. DPH affected neither the mRNA expression of RANKL and osteoprotegerin nor the growth of mouse osteoblasts in culture. On the other hand, DPH inhibited the RANKL-induced formation of osteoclasts in cultures of mouse bone marrow–derived macrophages (BMMϕs) and of human peripheral blood-derived CD14+ cells. DPH concealed LPS-induced bone resorption in mouse calvarial organ cultures and inhibited the pit-forming activity of mouse osteoclasts cultured on dentine slices. DPH suppressed the RANKL-induced calcium oscillation and expression of nuclear factor of activated T cells c1 (NFATc1) and c-fos in BMMϕs. Moreover, DPH inhibited the RANKL-induced nuclear localization and auto-amplification of NFATc1 in mature osteoclasts. Both BMMϕs and osteoclasts expressed mRNA of a T-type calcium channel, Cav3.2, a target of DPH. Blocking the expression of Cav3.2 by short hairpin RNAs significantly suppressed RANKL-induced osteoclast differentiation. These results suggest that DPH inhibits osteoclast differentiation and function through suppression of NFATc1 signaling. The topical application of DPH may be a therapeutic treatment to prevent bone loss induced by local inflammation such as periodontitis.
1α,25(OH)2 Vitamin D3 Induction of ATP Secretion in Osteoblasts
Authors: Biswas Payal , Zanello Laura P
Published: March 2009

In the absence of mechanical stimulation, brief exposure of osteoblasts to 1α,25(OH)2vitamin D3 (1,25D) triggers plasma membrane electrical responses that couple to exocytosis. Here we describe for the first time 1,25D induction of exocytotic ATP release in static ROS 17/2.8 and SAOS-2 cells and primary calvarial osteoblasts expressing a vitamin D receptor (VDR). We found that 10 nM 1,25D optimally induced 45 ± 1% and 40 ± 1% of partial and complete exocytotic events, respectively, from a 1,25D-sensitive pool of ATP-containing secretory vesicles within 60 s. We measured a dose-dependent 1,25D induction of ATP secretion, with maximal response of ∼6.2-fold (16.93 ± 1.82 nM for SAOS-2) and 3.1-fold (18.89 ± 1.39 nM for ROS 17/2.8) obtained with 10 nM 1,25D compared with basal ATP levels (2.75 ± 0.39 nM, SAOS-2; 6.09 ± 0.58 nM, ROS 17/2.8 cells). The natural metabolite 25(OH)vitamin D3 (25D, 10 nM) induced a significant 3.6-fold increase of ATP release in ROS 17/2.8 cells, but there was no induction with the antagonist 1β,25(OH)2vitamin D3 (1β,25D, 10 nM) or the steroid 17β-estradiol (10 nM). 1,25D-induced ATP secretion was abolished when cells were preincubated with inhibitors of vesicular exocytosis. siRNA VDR silencing prevented 1,25D stimulation of ATP exocytosis in ROS 17/2.8 and SAOS-2 cells. Similarly, 1,25D failed to stimulate ATP exocytosis in primary osteoblasts from a VDR knockout mouse. ATP secretion coupled to 1,25D induction of cytosolic calcium and chloride channel potentiation. Rapid 1,25D stimulation of ATP secretion involving nontranscriptional VDR functions in osteoblasts may help explain 1,25D bone anabolic properties.
Image Analysis Algorithms for Immunohistochemical Assessment of Cell Death Events and Fibrosis in Tissue Sections
Authors: Krajewska Maryla , Smith Layton H. , Rong Juan , Huang Xianshu , Hyer Marc L. , Zeps Nikolajs , Iacopetta Barry , Linke Steven P. , Olson Allen H. , Reed John C. , Krajewski Stan
Published: March 2009

Cell death is of broad physiological and pathological importance, making quantification of biochemical events associated with cell demise a high priority for experimental pathology. Fibrosis is a common consequence of tissue injury involving necrotic cell death. Using tissue specimens from experimental mouse models of traumatic brain injury, cardiac fibrosis, and cancer, as well as human tumor specimens assembled in tissue microarray (TMA) format, we undertook computer-assisted quantification of specific immunohistochemical and histological parameters that characterize processes associated with cell death. In this study, we demonstrated the utility of image analysis algorithms for color deconvolution, colocalization, and nuclear morphometry to characterize cell death events in tissue specimens: (a) subjected to immunostaining for detecting cleaved caspase-3, cleaved poly(ADP-ribose)-polymerase, cleaved lamin-A, phosphorylated histone H2AX, and Bcl-2; (b) analyzed by terminal deoxyribonucleotidyl transferase–mediated dUTP nick end labeling assay to detect DNA fragmentation; and (c) evaluated with Masson's trichrome staining. We developed novel algorithm-based scoring methods and validated them using TMAs as a high-throughput format. The proposed computer-assisted scoring methods for digital images by brightfield microscopy permit linear quantification of immunohistochemical and histochemical stainings. Examples are provided of digital image analysis performed in automated or semiautomated fashion for successful quantification of molecular events associated with cell death in tissue sections. (J Histochem Cytochem 57:649–663, 2009)
Proposed Changes in Lease Accounting and Private Business Bankers' Credit Decisions*
Authors: Durocher Sylvain , Fortin Anne
Published: March 2009

This study contributes to the debate on lease accounting currently ongoing at the international level and to future discussions at the Canadian level for private enterprise standards following a potential revision of lease accounting in international financial reporting standards (IFRS). A user perspective is adopted to examine private business bankers' preferences on the issue of capitalizing all noncancelable lease contracts, including operating leases, as suggested by the G4+1. While bankers use both capital and operating lease information, they give significantly more consideration to the former when analyzing private business loan requests. Accordingly, operating lease information receives less attention than capital lease information in the credit‐granting decision process. In addition, private business bankers consider a number of aspects of the current lease accounting standard to be inadequate and are in favor of the principles governing the approach suggested by the G4+1. They feel that the capitalization of operating leases would improve their ability to evaluate lessees' long‐term financial commitments and increase their estimates of the risks involved in providing financing to lessees. This study also demonstrates that the capitalization of operating leases would have a significant impact on key financial indicators of a sample of Canadian private companies. Bankers perceive that these realistic changes in financial indicators would affect their assessment of borrowers' capital structure/solvency, liquidity, ability to repay, and risk rating. From a cost‐benefit perspective, the findings provide standard‐setters with an indication of the benefits of the G4+1 proposals to users.
Determination of fetal heart rate reactivity from a single 20-min window of non-stress testing in compromised fetuses
Authors: Park Young-Sun , Hoh Jeong-Kyu , Koh Seung-Kwon , Kim Nam-Su , Park Moon-II
Published: March 2009

Aims: To shorten the analysis time needed for non-stress testing (NST) without decreasing efficacy in compromised fetuses.

Methods: We selected 80 cases with a 5-min Apgar score <7 as a study group and 259 cases with a 5-min Apgar score ≥9 as a control group. We applied four different criteria (A, B, C, and D) to each study and control group for the first 20-min window of NST data to evaluate reactivity. Criteria A, B, and C consisted of conventional reactivity criteria according to amplitude (15 or 10 beats per minute), duration (15 or 10 s) and weeks of gestation (≤31, ≥32), and criteria D combined criteria C with approximate entropy (ApEn).

Results: The sensitivity of criteria D (91.25%) was greater than the other three criteria (P<0.0001). The specificities of criteria C (96.14%) and D (99.23%) were also higher than criteria A and B (P<0.0001). The positive and negative predictive value of criteria D were better than that of criteria C (97.33 vs. 83.87, P=0.0066) and (97.35 vs. 89.89, P=0.0004), respectively.

Conclusion: Adding ApEn to the conventional criteria for reactivity shortened NST analysis time without decreasing efficacy, facilitating a decision of reactivity within a single 20-min NST window.
Glossar Verkehrsflugzeuge (DE–EN) (2. Teil)
Authors: Weilandt Annette
Published: March 2009

Der europäische Konzern Airbus Industries hat erstmals mehr Flugzeuge verkauft als der amerikanische Konkurrent Boeing, und der Flugverkehr nimmt, nicht zuletzt durch die sog. Billigf lieger, weiter zu. Ob dies einhergeht mit einem zunehmenden Translationsbedarf im Bereich Flugzeugbau wäre interessant zu wissen; in jedem Fall ist es für Übersetzer und Dolmetscher interessant, zumindest die Grundbegriffe und Benennungen der Verkehrsflugzeuge zu kennen. Das folgende Glossar stammt aus dem dritten Hauptteil der Diplomarbeit „Verkehrsflugzeuge. Eine terminologische Untersuchung im Deutschen und Englischen“, die am 20.10.2003 am Institut für Angewandte Linguistik und Translatologie (IALT) der Universität Leipzig eingereicht wurde. Das mit CATS erstellte Glossar enthält 848 Datensätze mit 346 Begriffen, 587 dt. und 616 engl. Benennungen sowie deutschen und englischen Definitionen nahezu aller Begriffe; im Folgenden drucken wir die Richtung deutsch-englisch.
Zum Qualitätsbegriff beim Dolmetschen
Authors: Kalina Sylvia
Published: March 2009

Welche Aussagen zur Dolmetschqualität sind aus der Vergangenheit belegt, und wie wird die Fragestellung in der Gegenwart behandelt? Wie lässt sich Dolmetschqualität messen? Wer beurteilt die Qualität von Dolmetschleistungen, und auf welcher Basis geschieht das? Um nicht nur die verschiedenen Blickwinkel zu berücksichtigen, sondern in eine Bewertung auch die Bedingungen des Dolmetschprozesses einzubeziehen, wird im folgenden Artikel ein erweitertes Anforderungsprofil entwickelt, das vom Dolmetschen als kommunikativer Interaktion ausgeht und im weitesten Sinne zur Qualitätssicherung beim Dolmetschen beitragen soll. Anregungen und Kommentare von Lesern sind der Autorin sehr willkommen.
Brücken-Glossar (DE–EN) (1. Teil)
Authors: Wuttke Susanne
Published: March 2009

Brücken scheinen neuerdings auch von der Öffentlichkeit bewusster wahrgenommen zu werden, jedenfalls fällt auf, dass sich gerade in jüngster Zeit in den Printmedien und im Fernsehen Beiträge mit dem Brückenbau befasst haben. Das folgende Glossar stammt aus dem dritten Hauptteil der Diplomarbeit „Brücken. Eine terminologische Untersuchung im Deutschen und Englischen“, die am 18.09.2003 am Institut für Angewandte Linguistik und Translatologie (IALT) der Universität Leipzig eingereicht wurde. Das mit CATS erstellte Glossar enthält 1374 Datensätze mit 467 Begriffen, 937 dt. und 904 engl. Benennungen sowie deutschen und englischen Definitionen nahezu aller Begriffe; im Folgenden drucken wir die Richtung Deutsch-Englisch.
Du bist ein 286
Authors: Fang Weigui
Published: March 2009

»Welch ein Mangel von Erfindungskraft im Großen und welche unselige Feinheit in Kleinigkeiten gehörte dazu, dieser Sprache aus einigen rohen Hieroglyphen die unendliche Menge von achtzigtausend zusammengesetzten Charakteren zu erfinden, in welchen sich nach sechs und mehr Schriftarten die Sinesische Nation unter allen Völkern der Erde auszeichnet«, so heißt es bei J. G. Herder (1744–1803) in seinen Ideen zur Philosophie der Geschichte der Menschheit.

»Die Chinesen sind gar kein Volk, sie sind eine bloße Menschheit«, behauptet F. W. J. Schelling (1775–1854). Selbst die monosyllabische chinesische Sprache, in der die »siderische Kraft« der Ursprache wohne, sei »wie eine Sprache aus einer andern Welt«. (Philosophie der Mythologie)
Textsortenkonventionen nach Sendertyp am Beispiel der kontrastiven Analyse (Deutsch-Spanisch) von rekurrenten Teiltextsegmenten in der für das Ausland bestimmten Sprachkursbroschüre (FABS)
Authors: Fernández Francesc
Published: March 2009

Im vorliegenden Beitrag, der auf einer korpusgestützten, nach Teiltexten durchgeführten Analyse spanischer und deutscher Exemplare von Sprachkursbroschüren mit öffentlichem und privatem Sender basiert, wird der Frage nach dem Einfluss nachgegangen, den der Sendertyp – gegenüber der Linguokultur – auf jene Textsortenkonventionen der FABS ausübt, die mit rekurrenten Teiltextsegmenten – untergliedert in formelhafte, halbformelhafte und nicht formelhafte – zu tun haben. Dies erfolgt durch die exemplarische Untersuchung der zwei längsten und somit erwartungsgemäß repräsentativsten Teiltexte zweiten Grades des Teiltextes ersten Grades „Wir über uns“, dem insofern eine besondere Bedeutung zukommt, als sich darin jeder Sendertyp auf eigene Weise zu profilieren trachtet. Die Ergebnisse der Untersuchung zeigen, dass bei allem Vorrang der Linguokultur sich auch der Sendertyp als relevanter Bestimmungsfaktor erweist, insbesondere bei den deutschen Exemplaren mit privatem Sender, die zudem größere Unterschiede zu den deutschen Exemplaren mit öffentlichem Sender aufweisen, als es bei ihren jeweiligen spanischen Pendants der Fall ist.
High-Rate Time-Dependent Displacement Gage for HE Field Tests
Authors: Michaelis Ron , Anteby Ido , Gal Erez , Sadot Oren , Ben-Dor Gabi
Published: March 2009

A dynamic gage, capable of continuously measuring high-rate displacements of structures, has been developed and tested by the research team of the Protective Technologies Research & Development Center (PTR&DC) of the Faculty of Engineering Sciences of the Ben-Gurion University of the Negev. The gage, which was originally developed in order to monitor the time-dependent displacements of concrete slabs subjected to explosion-generated blast wave impacts, can be used to monitor the displacement of any structure that is exposed to high-rate dynamic loads. The displacement gage is based on a torsion tube, twisted by a long flexure element that is connected to the measured point or structure. The twist of the torsion tube is monitored by strain gages. The displacement gage was tested in the impact pendulum laboratory of the PTR&DC, and will be used in high explosive (HE) field tests.
Effect of the Heat-Affected Zone at the Crack-Starter Bead on the Nil-Ductility Transition Temperature of Steels Determined by the Drop-Weight Test
Authors: Koshizuka N , Enami T , Tanaka M , Hiro T , Kusuhara Y , Fukuda H , Yoshimura S
Published: March 2009

The effect of the heat-affected zone (HAZ) at the crack-starter bead on the nil-ductility transition temperature (NDTT) of drop-weight test specimens of pressure vessel steels was investigated. NDTT varied with changes in thermal cycles in the bead welding and increased linearly with the hardness of HAZ. Using fracture toughness of the base metal and HAZ geometry, NDTT was estimated and compared with the observed NDTT. The difference between the estimated NDTT and the observed NDTT was caused by changes in HAZ hardness. The observed NDTT became lower with softening of HAZ.
Finite-Element Analysis of Eddy-Current Flaw Detection
Authors: Chari MVK , Kincaid TG
Published: March 2009

The eddy-current nondestructive evaluation (NDE) inversion problem is to determine flaw parameters from eddy-current sensor impedance changes. Two approaches to solving this problem are discussed for geometries with two components of eddy current. The first is to use the finite-element method of numerical analysis to compute the sensor impedance change for each flaw parameter value. The second approach is to combine the finite-element method with an analytical scattering technique. These two approaches are applied to the problem of an infinitely long coil surrounding an infinitely long conducting bar with an infinitely long surface crack. The calculated impedance changes show good agreement with known analytical and experimental results.
Secondary Conductivity Standards Stability
Authors: Jones AR
Published: March 2009

Calibration values of secondary conductivity standards obtained on a periodic basis, both for the Boeing Company and for commercial customers, have shown various drift patterns. Presently, a 100-kHz bridge used with an H-P 9825 computer compares unknown secondary standards against carefully built, National Bureau of Standards (NBS) traceable, primary bars in an oil-bath environment. Factors affecting the stability of secondary standard values of conductivity include primary conductivity bar value changes, uneven surface wear, environmental contamination, lift-off due to the presence of foreign material on the surface, and aging of the metal crystalline structure. Some secondary standards, which were large physically, exhibited significant conductivity changes across their surface due to the nonhomogeneity of the metal.

Original calibration of secondary standards was accomplished by assigning the same value to a section cut from the primary bar that was given to the primary bar itself. When new alloy metals were obtained, as older metal primary bar material was exhausted for secondary use, an H-P 65 program was developed to utilize a curve-fitting method for replacement secondary-standard material calibration. Some changes in older secondary values resulted from this method. An H-P 9825 computer program was later developed, which resulted in other secondary-value changes. During the last twelve years some significant changes occurred in the primary bars, which further altered the program and the calibration results. New primary bars have been also added from time to time to smooth out the curve-fitting program, which has some effect on the calibration values of the secondary standards.
Opitimization of a Multifrequency Eddy-Current Test System Concerning the Defect Detection Sensibility
Authors: Becker R , Betzold K
Published: March 2009

A multifrequency algorithm is applied to suppress signals caused by disturbing parameters. This procedure (based on the projection principle in a multidimensional vector space) and the electronics employed in prototype form are described. The prototype operates with up to four frequencies in a wide range (500 Hz to 1 MHz). The frequencies are continuously tunable and are fed into the coil one after the other by high-speed multiplexing. The multifrequency approach yields a read-out value affected only by defects. The defect signals then can be assessed by means of reference defects of known depths giving equivalent indication peaks. The elimination of the disturbing signals chiefly increases defect detection sensitivity. In general, however, the suppression is not total, and, additionally, the original defect signals are reduced to a greater or lesser degree by the application of the projection principle. The testing frequencies used have a strong influence on the projection losses and therefore on the defect detection sensitivity. A computer program system that allows the reaction of the impedance of the coil to be calculated as a function of the electric, magnetic, and geometrical properties of the specimens and the dimensions of the coil itself is used to determine an optimum frequency combination for the given test situation. This procedure is applied to the testing of heat-exchanger tubes, claddings, and welded joints. The results obtained with the optimized test system are presented.
The Use of A-C Field Measurements to Determine the Shape and Size of a Crack in a Metal
Authors: Dover WD , Charlesworth FDW , Taylor KA , Collins R , Michael DH
Published: March 2009

An instrument designed to measure the a-c field accurately has been built and fully tested on steel, aluminium, and titanium. These field measurements can be interpreted in terms of crack size, which provides a new technique for nondestructive testing (NDT) that requires no prior calibration. This paper describes the basic electronic measuring system, theoretical derivations of the electrical-field distribution, and application to industrial problems such as crack measurement in threads, shafting, welded connections, etc.
Experimental and Analytical Study of Fatigue Damage in Notched Graphite/Epoxy Laminates
Authors: Whitcomb JD
Published: March 2009

Fatigue damage development in notched (0/±45/0)s, (45/0/−45/0)s, (90/±45/0)s, and (45/90/−45/0)s graphite/epoxy laminates was investigated. Both tension and compression fatigue behaviors were studied. Most of the tests were conducted at load levels equal to two thirds of the ultimate tensile strength of the notched specimens. After fatigue loading, specimens were examined for damage type and location using light microscopy, scanning electron microscopy, ultrasonic C-scans, and X-radiography. Delamination and ply cracking were found to be the dominant types of fatigue damage. In general, ply cracks did not propagate into adjacent plies of differing fiber orientation. To help understand the varied fatigue observations, the interlaminar stress distribution was calculated with finite element analysis for the regions around the hole and along the straight free edge. Comparison of observed delamination locations with the calculated stresses indicated that both interlaminar shear and peel stresses must be considered when predicting delamination. The effects of the fatigue cycling on residual strength and stiffness were measured for some specimens of each laminate type. Fatigue loading generally caused only small stiffness losses. In all cases, residual strengths were greater than or equal to the virgin strengths.
Compression Fatigue Behavior of Graphite/Epoxy in the Presence of Stress Raisers
Authors: Rosenfeld MS , Gause LW
Published: March 2009

Graphite/epoxy composites are being applied to aircraft structures because of their demonstrated capability to reduce weight and increase life. Although composites have better fatigue properties than metals, their behavior differs significantly. Unlike metals, composites exhibit excellent tensile fatigue behavior—the constant amplitude fatigue strength at 107 cycles being close to static ultimate. Compression and reversed loading fatigue behavior in the presence of stress raisers, however, has not been well characterized. This program was therefore undertaken to determine the characteristics of composites under these conditions. Two stress raisers were considered; the first was an open hole and the second was damage resulting from low velocity, hard object impact.

For the open hole specimen, constant and variable amplitude tests were performed to determine the significance of compression fatigue and to investigate the failure mechanism. These tests indicated that the fatigue life under compression and reversed loading is less than for tension-tension loading and will be an important design consideration in future composite applications. The failure mechanism appeared to be local progressive failure of the matrix near the stress raiser resulting in delamination, and final failure by fiber buckling. The variable-amplitude loading results also demonstrated the unconservativeness of Miner's rule for making analytical predictions.

In order to determine the nature and significance of impact damage to generic composite structural elements, low velocity impact and residual properties tests were conducted on solid laminate specimens of 42 and 48 plies thick and on honeycomb sandwich specimens with 12-ply composite face sheets. Results of post impact properties tests indicate subvisual damage can degrade compression static and fatigue strength, although subvisual damage will not propagate under moderate (0.003) cyclic strain.
Fatigue Retardation Due to Creep in a Fibrous Composite
Authors: Sun CT , Chim ES
Published: March 2009

A series of experiments were performed in an attempt to investigate the effect of creep strain and temperature on the fatigue life of a [±45]2s graphite/epoxy composite laminate. The experimental results indicate that sustained periods of static loads have significant retardation effects and that cyclic loading with a lower frequency preceeding one with a higher frequency also prolongs the fatigue life.
Off-Axis Fatigue of Graphite/Epoxy Composite
Authors: Awerbuch J , Hahn HT
Published: March 2009

Off-axis static and fatigue behavior of AS/3501-5A graphite/epoxy was studied in an effort to characterize the matrix/interface-controlled failure. Seven different off-axis angles were tested: 0, 10, 20, 30, 45, 60, and 90 deg. Initial (static) and post-fatigue residual strength were obtained together with S-N relationships. Fracture surfaces were examined through photomicrographs and stereo (three-dimensional) scanning electron microscope (SEM) photographs, in order to delineate failure modes, and the results of these inspections are discussed. The off-axis static strength, including scatter, was fully characterized by a polynomial and a nondimensional strength parameter. Essentially, no strength or modulus degradation was observed in the specimens surviving fatigue loading of 106 cycles regardless of the off-axis angle or fatigue stress level. When fatigue stress level is normalized with respect to static strength, all data seem to fall on the same S-N curve. Fatigue failure occurred without any warning or visible damage. Matrix failure characteristics vary with off-axis angle and appear in the form of serrations and axial and transverse cracks. Large scatter in life was observed at all off-axis angles; however, since the number of specimens employed in the present study is not sufficient to provide meaningful statistical S-N data, a more detailed investigation of the off-axis (and angle ply) behavior of graphite/epoxy composites is warranted.
Estimation of Weibull Parameters for Composite Material Strength and Fatigue Life Data
Authors: Talreja R
Published: March 2009

Two classical methods for estimation of Weibull parameters, namely, the moment estimation and the maximum likelihood estimation are reviewed. It is demonstrated that, assuming the location parameter to be zero, the errors made in estimating both the scale and the shape parameters by these methods increase linearly with the true value of the location parameter.

An alternative method for Weibull parameter estimation is proposed. This method provides estimates for all three parameters when the shape parameter is close to one, and estimates the scale and the shape parameters more accurately than the other two methods for higher values of the shape parameter. Furthermore, unlike the other methods, this method is capable of separating the constituent components in a multi-component sample and estimating the parameters of each component. This property makes the method suitable for statistical analysis of composite material strength and fatigue life data.
Effects of Copper on the Periphyton of a Small Calcareous Stream
Authors: Weber CI , McFarland BH
Published: March 2009

The effect of the continuous addition of copper to a small calcareous stream at a concentration of approximately 120 μg/litre was studied for a year. Of the parameters evaluated in this study, the species composition of the periphyton was found to be the most sensitive and informative measure of the effects of copper. Two of the dominant species of algae in the stream were eliminated from the periphyton: the diatom Cocconeis placentula var. euglypta, and the filamentous green alga, Cladophera glomerata. Cocconeis placentula, which commonly contributed 85 to 98 percent of the summer diatoms in the treated reach of the stream prior to the addition of copper, was replaced by three species of diatoms, Nitzschia palea, Navicula nigrii, and N. seminulum var. hustedtii. Other species of algae that were more abundant in the copper-treated reach than in the control reach of the stream were the filamentous blue-green alga, Schizothrix calcicola, and the desmids, Cosmarium granatum and C. subprotumidum.
Fracture Toughness Testing of HDPE Plastic Pipe
Authors: Fueler P , Roberts DR , Mandell JF , McGarry FJ
Published: March 2009

A program to investigate the applicability of fracture toughness test methods to high density polyethylene pipe is described. Fracture toughness test specimens cut from pipe material were tested in a precracked three-point bending test at different rates. The load versus crack opening displacement record was used in an attempt to judge the validity of the test and to determine the fracture load. This method appears to need further development for this class of materials, as the results were difficult to interpret. Use of the maximum force for tests which appeared to fail in a quasibrittle manner resulted in calculation of a fracture toughness value which generally did not satisfy validity conditions. This value was used to predict the burst pressure of pipes containing surface cracks in the longitudinal direction. The prediction of burst pressure was slightly conservative, but in agreement with the trend of the experimental results. Fractographic analysis indicates three modes of crack propagation: ductile, quasibrittle, and brittle.
Instrumented Impact Testing for Evaluating End-Use Performance
Authors: Ireland DR
Published: March 2009

Several applications of the instrumented impact test for evaluations of polymers and fiber reinforced polymers are discussed. These include simple flex bar, falling dart, and end-use component tests. Instrumented impact testing provides a complete record of the load applied to the specimen during the entire impact event. Distinct characteristics of the load record indicate the deformation and fracture process in the specimen. Subsequent analysis permits detailed study of the various fracture modes. Total absorbed energy is simply segmented into that required for initiating failure and that for propagating the fracture. Results of the laboratory impact test can then be evaluated with respect to the specific properties of interest for the product end-use.
On Abrasion, Scratch, and Friction Testing—Relationship to End-Use Application
Authors: Carroll JF
Published: March 2009

In the field of plastic testing, reproducibility is usually emphasized in standard test methods. However, relevancy is at least equally important to end-use applications. In the field of surface testing, relevancy can sometimes be more difficult to achieve.

Both ASTM and nonstandard abrasion tests for plastics are compared with ANSI abrasion tests for photographic film. Mechanisms include falling carborundum, abrasive loaded wheels, soft-hair wheelbrush, and spherical stylus. All give similar rankings when testing simple plastics surfaces. Only the spherical stylus produces results reliably related to trade experience with the thin coatings on photographic films.

Lubricity is introduced relative to its effect on abrasion resistance and ease of product handling by mechanical equipment. The classical ASTM friction test for plastics is a sled test. A sled test's lack of relevancy to scratch testing exemplifies a breakdown of the classical laws of friction. In the photographic film field, a point-contact friction test is more correlative. The ANSI version of this, the Paper Clip Friction Test, is described, and correlations with scratch as well as with lubricant levels in molded plastics are presented.
Testing Plastics for Performance: Meeting the Challenge of the Future
Authors: O'Toole JL
Published: March 2009

Previous papers have analyzed the problems of testing viscoelastic materials for end-use performance, summarized the current state of the art, and suggested various approaches to improving our rate of progress. One proposition on which all agree, there is a great deal of work to do that is challenging both technically and logistically. One of the principal areas of challenge one whose solution would have far reaching benefits, is also one for which the American Society for Testing and Materials Committee D-20 (ASTM) is uniquely positioned to attack. This is the interface between viscoelastic material science and the technology of analytical design. More than any other single factor, the inherent interdisciplinary nature of plastics design has frustrated the development and promulgation of a complete and coherent performance testing system. A program and organization whereby D-20 can meet this challenge will be outlined.
Stockpile Focus on Ferroalloys
Authors: Corder RE
Published: March 2009

This paper deals with stockpiling of various ferroalloys in the National Defense Stockpile. The purpose and philosophy of stockpiling various forms of strategic and critical materials for national defense emergencies are discussed in addition to a historical review of the background and history of stockpiling various ferroalloys.

The methodology and econometric computer modeling used to calculate the overall stockpile quantities are described as well as the method used for calculating specific quantities of each ferroalloy. The potential pitfalls and problems associated with changes in specifications, industry usage patterns, and geographical shifts in production centers are included in the discussion.

The results of the use of the new methods and the effects on future stockpiling plans are presented.
Titanium and Its Alloys for Use in Iron and Steelmaking
Authors: Demos AC , Kremin DW
Published: March 2009

This paper covers the various titanium alloys that are available to the foundry and steelmaking industry. It describes ferrotitanium products and titanium alloy scrap materials, comparing the analysis of the ferroalloy with the scrap products. A brief description of the method of preparation is included for both the ferro and the scrap metal additives.
Alternating-Current Impedance Measurements Applied to Corrosion Studies and Corrosion-Rate Determination
Authors: Epelboin I , Gabrielli C , Keddam M , Takenouti H
Published: March 2009

The general features of the a-c impedance at a metal-electrolyte interface as a function of frequency are depicted, and recently developed measurement techniques are described. It is established that at low and very low frequencies, down to the millihertz domain, relaxation phenomena are found in those cases where the assumptions used in Stern's derivation are not met. Under such conditions polarization resistance techniques can hardly be used owing to experimental and theoretical reasons. Charge transfer resistance, when used instead of polarization resistance in a Stern's type equation, is proved to overcome these difficulties on the basis of a theoretical derivation. Correlation between charge transfer resistance and corrosion rate is illustrated by practical examples of pure iron and anodized aluminum alloys.
Impedance Measurements on Organic Coatings on Mild Steel in Sodium Chloride Solutions
Authors: Scantlebury JD , Ho KN , Eden DA
Published: March 2009

Alternating-current impedance techniques were applied to organic coatings on mild steel in dilute sodium chloride solutions. The coatings used and the thicknesses employed were chosen to be typical of those systems frequently used for total immersion in marine conditions. A transfer function analyzer was used with high-impedance interfaces, and information was obtained concerning the impedance behavior of these coatings at frequencies that had previously been impossible. Equivalent circuit models analyzed the data obtained, and an assessment of the behavior of these coatings was made in the light of the analysis.
Evaluation of Electrochemical Techniques for Monitoring of Atmospheric Corrosion Phenomena
Authors: Mansfeld F
Published: March 2009

A review is presented of past and present efforts to use electrochemical techniques to evaluate basic phenomena of atmospheric corrosion, measure time of wetness, and perform corrosion-rate measurements in outdoor exposure. This is followed by a summary of recent work carried out in the author's laboratory. Time-of-wetness measurements have been carried out continuously over a three-year period at the same location using copper/steel and copper/zinc sensors. An analysis of the monthly distribution of relative humidity and corrosion rates determined with the same sensors has resulted in correlations between them. Weight-loss measurements under thin layers of electrolytes that are drying out at RH < 100 percent have shown that, in most cases, corrosion rates are much higher under these conditions than in bulk solutions. Electrochemical measurements carried out under identical conditions show the continuous increase of corrosion rates during the drying period. A comparison of corrosion rates determined by weight loss and electrochemical techniques under thin layers of electrolytes indicates that the electrochemical data underestimate the true corrosion rates. The determination of cell factors based on weight-loss data is one approach for using the electrochemical technique in a more quantitative manner.
Electrochemical Behavior of Carbon Steel in Fused Salts
Authors: Chen CM , Theus GJ
Published: March 2009

The polarization resistance method was used to assess the corrosion rate and to study the oxidation kinetics of carbon steel in a fused nitrate-sulfate-chloride salt mixture at 316°C (600°F) and in an alkali iron trisulfate salt at 677°C (1250°F). The same method was also applied to estimate the corrosion rate of carbon steel through the solidified frozen alkali iron trisulfate salt.

Equilibrium potential/pO2− diagrams were constructed for iron, nitrate, and nitrate-reaction products to aid in the interpretation of corrosion data for the nitrate-rich salt and to determine the various chemical reactions causing the corrosion.