bluuebunny/crossref_metadata_2025 huggingface dataset:
Oestrogen modulates human macrophage apoptosis via differential signalling through oestrogen receptor‐α and β
Authors: Subramanian Manikandan , Shaha Chandrima
Published: January 2009

Human macrophages express oestrogen receptors and are therefore competent to respond to the hormone present in their microenvironment, which is implicated in sexual dimorphism observed in several immune and autoimmune phenomena. An earlier study from this laboratory demonstrated 17β‐oestradiol (E2) induced apoptosis in macrophages derived from human peripheral blood monocytes and THP‐1 acute monocytic leukaemia cell line when Bcl‐2 was down‐regulated; however, the involvement of E2 receptor subtypes in the modulation of death pathways in these cells remain unknown. Using macrophages derived from THP‐1 human acute monocytic leukaemia cells as a model, we demonstrate that plasma membrane associated oestrogen receptor (ER) ‐α participate in E2 induced Bcl‐2 increase, through activation of the mitogen activated protein kinase (MAPK) pathway whereas cytosolic ER‐β transmits signals for the pro‐apoptotic event of Bax translocation. The mechanistic basis of Bax translocation comprised of ER‐β mediated increase in intracellular pH, facilitated by activation of the Na+–H+ exchanger. Intracellular alkalinization accompanied by concomitant Bcl‐2 increase and Bax migration does not cause cellular apoptosis; however, siRNA mediated down‐regulation of ER‐α during E2 exposure leads to inhibition of Bcl‐2 increase and consequently apoptosis due to the unopposed action of mitochondrial Bax. In summary, this study underscores the importance of integrative signalling modality from multiple oestrogen receptor pools in modulating oestrogen effects on human monocyte‐derived macrophage apoptotic signalling pathway, which opens new vistas to explore the use of selective oestrogen receptor modulators in apoptosis‐based therapies.
Characterization of the S‐denitrosylating activity of bilirubin
Authors: Barone Eugenio , Trombino Sonia , Cassano Roberta , Sgambato Alessandro , de Paola Barbara , Stasio Enrico Di , Picci Nevio , Preziosi Paolo , Mancuso Cesare
Published: January 2009

Bilirubin‐IX‐α (BR) is an endogenous molecule with a strong antioxidant feature due to its ability to scavenge free radicals. In this paper, we demonstrated that BR, at concentrations close to those found within the cell (0.1–2.5 μM), acted as a denitrosylating agent and increased the release of nitric oxide from S‐nitrosoglutathione (GSNO) and S‐nitrosocysteine (SNOC) (2.5 μM). The complexation of BR with saturating concentrations of human serum albumin (HSA, 2.5 μM) did not further increase nitric oxide release from GSNO and SNOC. At concentrations similar to those reached in plasma (5–20 μM), BR denitrosylated S‐nitroso‐HSA (2.5 μM), the main circulating S‐nitrosothiol, and this effect was potentiated by the complexation of BR with saturating HSA (20 μM). Furthermore, the product(s) of the reaction between nitric oxide and BR were identified. Ultraviolet and mass spectrometry analysis revealed that nitric oxide binds to BR forming a N‐nitroso derivative (BR–nitric oxide) with extinction coefficients of 1.393 mM−1cm−1and 2.254 mM−1cm−1in methanol and NaOH, respectively. The formation of BR–nitric oxide did not occur only in a reconstituted system, but was confirmed in rat fibroblasts exposed to pro‐oxidant stimuli. These results provided novel insights on the antioxidant characteristic of BR through its interaction with nitric oxide, a gaseous neurotransmitter with a well‐known dual effect, namely neuroprotective under physiological conditions or neurotoxic if produced in excess, and proposed BR–nitric oxide as a new biomarker of oxidative/nitrosative stress.
Sensitizing capacity and cross‐reactivity of phenyl glycidyl ether studied in the guinea‐pig maximization test
Authors: Pontén Ann , Zimerson Erik , Bruze Magnus
Published: January 2009

Background:  Simultaneous contact allergies to the reactive diluent phenyl glycidyl ether (PGE) and epoxy resins based on diglycidyl ether of bisphenol A (DGEBA) or epoxy resins of the bisphenol F‐type have been reported. The latter epoxy resins contain three isomers of diglycidyl ether of bisphenol F (DGEBF). PGE, DGEBA, and DGEBF are chemically similar with respect to the reactive glycidyl group and an aromatic ring, making cross‐reactivity one of the possible explanations to simultaneous reactions.

Aim:  To investigate the sensitizing capacity of PGE and the cross‐reactivity of PGE versus the epoxy resin monomers DGEBA and the three DGEBF monomers and vice versa.

Method:  The guinea‐pig maximization test.

Results:  PGE is a strong sensitizer. Induction with DGEBA resulted in a statistically significant number of animals reacting to PGE, but when induced with PGE, the animals did not react significantly to DGEBA.

Conclusions:  When the results are applied to humans, it can be assumed that patients sensitized primarily to DGEBA react to PGE, but when sensitized exclusively to PGE, they do not react to DGEBA. Both reactive diluents and epoxy resins should be tested when contact allergy to epoxy resin systems are suspected.
Assessment of the sensitization potential of persulfate salts used for bleaching hair
Authors: Cruz María‐Jesús , De Vooght Vanessa , Muñoz Xavier , Hoet Peter H. M. , Morell Ferran , Nemery Benoit , Vanoirbeek J. A. J.
Published: January 2009

Background:  Persulfate salts have been associated with both allergic contact dermatitis and bronchial asthma. Because there is currently no experimental data available on the sensitizing properties of persulfate salts (ammonium, sodium, and potassium persulfates), we determined their dermal sensitizing capacity, using the murine local lymph node assay (LLNA).

Material and Methods:  For three consecutive days, BALB/c mice were dermally treated with ammonium, sodium, or potassium persulfate or with the vehicle alone (dimethyl sulfoxide) on each ear (2 × 25 μl). On D6, mice were injected intravenously with [3H]‐methyl thymidine. The draining auricular lymph nodes were removed, and the incorporation of [3H]‐methyl thymidine was compared with that of vehicle‐treated control mice. A stimulation index (SI) relative to the vehicle‐treated control value was derived. The sensitizing potency of the chemicals tested was determined by estimating the concentration of chemical required to induce a SI of 3 (EC3).

Results:  All three chemicals provoked positive responses in the LLNA, with dose‐dependent increases in proliferation. Maximal SIs recorded were 6.8 ± 1.8, 6.5 ± 1.2, and 5 ± 1.0 at 5% for ammonium, sodium or potassium persulfate, respectively. The EC3 values were 1.9%, 0.9%, and 2.4% for ammonium, sodium, and potassium persulfates, respectively.

Conclusions:  All three persulfate salts need to be considered strong‐to‐moderate sensitizers according to the murine LLNA.
Contamination versus preservation of cosmetics: a review on legislation, usage, infections, and contact allergy
Authors: Lundov Michael Dyrgaard , Moesby Lise , Zachariae Claus , Johansen Jeanne Duus
Published: January 2009

Cosmetics with high water content are at a risk of being contaminated by micro‐organisms that can alter the composition of the product or pose a health risk to the consumer. Pathogenic micro‐organisms such as Staphylococcus aureus and Pseudomonas aeruginosa are frequently found in contaminated cosmetics. In order to avoid contamination of cosmetics, the manufacturers add preservatives to their products. In the EU and the USA, cosmetics are under legislation and all preservatives must be safety evaluated by committees. There are several different preservatives available but the cosmetic market is dominated by a few preservatives: parabens, formaldehyde, formaldehyde releasers, and methylchloroisothiazolinone/methylisothiazolinone.

Allergy to preservatives is one of the main reasons for contact eczema caused by cosmetics. Concentration of the same preservative in similar products varies greatly, and this may indicate that some cosmetic products are over preserved. As development and elicitation of contact allergy is dose dependent, over preservation of cosmetics potentially leads to increased incidences of contact allergy. Very few studies have investigated the antimicrobial efficiency of preservatives in cosmetics, but the results indicate that efficient preservation is obtainable with concentrations well below the maximum allowed.
Solitary superficial angiomyxoma: an infrequent but distinct soft tissue tumor
Authors: Satter Elizabeth K
Published: January 2009

Superficial angiomyxoma (SA) is a distinct soft tissue tumor characterized by a circumscribed collection of spindled and stellate fibroblasts that are admixed with thin‐walled blood vessels and embedded in a mucinous stroma. Because of its relative infrequent occurrence, the purpose of this article was to present a classical example of an isolated superficial angiomyxoma and discuss the differential diagnosis.
Multiple cutaneous sclerosing perineuriomas: an extensive presentation with involvement of the bilateral upper extremities
Authors: Rubin Adam I , Yassaee Mina , Johnson Waine , Elenitsas Rosalie , Zaladonis Joseph , Seykora John T.
Published: January 2009

A perineurioma is a benign peripheral nerve sheath neoplasm thought to be derived from cells of the perineurium, the cellular sheathing of peripheral nerve fascicles. The histological, immunohistochemical (positive for epithelial membrane antigen, collagen type IV, laminin and vimentin but not S‐100 protein) and ultrastructural features of a perineurioma form the basis for diagnosis. Two types of perineuriomas are recognized, intraneural and soft tissue (extraneural) forms. Sclerosing perineurioma is considered a variant of the soft tissue perineurioma. In all but one of the reported cases, this subtype presented as a solitary clinical lesion with a predilection for the fingers and palms of young adults. In 2002, Huang and Sung described a 16‐year‐old boy with one sclerosing perineurioma on each hand. The unusual case presented herein is a 21‐year‐old woman manifesting more than 30 cutaneous sclerosing perineuriomas on the hands and arms. This case is the most extensive presentation of sclerosing perineuriomas documented to date and extends the clinical presentation spectrum of these lesions.
Infiltrating intramuscular spindle cell lipoma of the face
Authors: Mandal Rajni V. , Duncan Lyn M. , Austen William G. , Nielsen G. Petur
Published: January 2009

Spindle cell lipoma is a benign lipomatous tumor, which usually arises on the back of the neck, shoulder or upper back of males in the third to seventh decade of life. We report herein an unusual infiltrating intramuscular spindle cell lipoma arising in the nose of a 53‐year‐old man. The patient presented with a 0.5‐cm ‘cyst’ of the nose, just above the right alar crease, which was removed. Four years later, the lesion recurred and was re‐excised. Histologically, a proliferation of mature adipocytes, ropey collagen fibers and spindle cells within a myxoid stroma was present in the subcutaneous tissue and infiltrated between skeletal muscle fibers. Nine cases of intramuscular spindle cell lipoma with histological examination have previously been reported and have involved the oral cavity and muscles of the extremities. To our knowledge, this is the first report of an infiltrating intramuscular spindle cell lipoma arising on the face.
A Potential‐Based Inversion of Unconfined Steady‐State Hydraulic Tomography
Authors: Cardiff M. , Barrash W. , Kitanidis P.K. , Malama B. , Revil A. , Straface S. , Rizzo E.
Published: January 2009

The importance of estimating spatially variable aquifer parameters such as transmissivity is widely recognized for studies in resource evaluation and contaminant transport. A useful approach for mapping such parameters is inverse modeling of data from series of pumping tests, that is, via hydraulic tomography. This inversion of field hydraulic tomographic data requires development of numerical forward models that can accurately represent test conditions while maintaining computational efficiency. One issue this presents is specification of boundary and initial conditions, whose location, type, and value may be poorly constrained. To circumvent this issue when modeling unconfined steady‐state pumping tests, we present a strategy that analyzes field data using a potential difference method and that uses dipole pumping tests as the aquifer stimulation. By using our potential difference approach, which is similar to modeling drawdown in confined settings, we remove the need for specifying poorly known boundary condition values and natural source/sink terms within the problem domain. Dipole pumping tests are complementary to this strategy in that they can be more realistically modeled than single‐well tests due to their conservative nature, quick achievement of steady state, and the insensitivity of near‐field response to far‐field boundary conditions. After developing the mathematical theory, our approach is first validated through a synthetic example. We then apply our method to the inversion of data from a field campaign at the Boise Hydrogeophysical Research Site. Results from inversion of nine pumping tests show expected geologic features, and uncertainty bounds indicate that hydraulic conductivity is well constrained within the central site area.
Travel Time Distributions Derived from Particle Tracking in Models Containing Weak Sinks
Authors: Visser A. , Heerdink R. , Broers H. P. , Bierkens M.F.P.
Published: January 2009

A travel time distribution based on a particle‐tracking analysis in a ground water model containing weak sinks is often uncertain because whether a particle is discharged or allowed to pass through a weak sink is unresolved by particle‐tracking theory. We present a probability‐based method to derive an objective travel time distribution in models containing weak sinks. The method discharges a fraction of the particle at the weak sink and allows the remaining fraction to pass through the weak sink. The weight of the discharged fraction depends on the ratio of the sink flux to the influx into the weak sink cell. We tested this approach on a coarse (100 × 100 m) and a fine (25 × 25 m) horizontal resolution regional scale ground water model (34.5 × 24 km). We compared the travel time distributions in a small subcatchment derived from particle‐tracking analysis with one derived from a transport model. We found that the particle‐tracking analysis with the coarse model underestimated the travel time distribution of the catchment compared to the transport solution or a particle‐tracking analysis with the fine model. The underestimation of travel times with the coarse model was a result of a large area covered by sink cells in this model and the more accurate flow patterns simulated by the fine model. The probability‐based method presented here compares favorably with a solute transport solution and provides an accurate travel time distribution when used with a fine‐resolution ground water model.
It's Time We Brought Introspection Out of the Closet
Authors: Locke Edwin A.
Published: January 2009

I identify the main reasons why introspection unofficially has been banned from the field for some 100 years, though it has been partly smuggled back in through the use of “verbal (self-) reports.” I then show why introspection is indispensable to psychology. I argue that this ban has retarded the progress of psychology by taking attention away from the problem of the accuracy of self-reports, limiting our understanding of concepts like emotion, discouraging psychologists from using introspection themselves, and ignoring the study of how to develop introspective skill. I conclude by suggesting some approaches to validating introspective reports.
We Have to Break Up
Authors: Cialdini Robert B.
Published: January 2009

Three mostly positive developments in academic psychology—the cognitive revolution, the virtual requirement for multiple study reports in our top journals, and the prioritization of mediational evidence in our data—have had the unintended effect of making field research on naturally occurring behavior less suited to publication in the leading outlets of the discipline. Two regrettable consequences have ensued. The first is a reduction in the willingness of researchers, especially those young investigators confronting hiring and promotion issues, to undertake such field work. The second is a reduction in the clarity with which nonacademic audiences (e.g., citizens and legislators) can see the relevance of academic psychology to their lives and self-interest, which has contributed to a concomitant reduction in the availability of federal funds for basic behavioral science. Suggestions are offered for countering this problem.
Recapturing a Context for Psychology: The Role of History
Authors: Benjamin Ludy T. , Baker David B.
Published: January 2009

With the ever-increasing fragmentation of psychology into narrower subspecialties, the field devolves further and further into a focus on specialized knowledge, answering smaller questions and avoiding the larger and more meaningful ones. It is argued that specialized knowledge acquires its meaning only from an understanding of its place in a broader intellectual context. Psychology appears to have lost that context and perhaps the opportunity for a more significant role in modern science. An understanding of the history of psychological science offers a way to recapture that context and to prepare future psychologists to address the truly significant behavioral problems that face our world.
The Air We Breathe: A Critical Look at Practices and Alternatives in the Peer-Review Process
Authors: Suls Jerry , Martin René
Published: January 2009

Anonymous peer review has served as the bedrock of research dissemination in scientific psychology for decades and has only sporadically been questioned. However, other disciplines, such as biomedicine and physics, have found the traditional peer-review system to be wanting and have begun to test and try alternative practices. In this article, we survey criticisms of the traditional peer-review system and describe several alternatives in the interests of facilitating discussion and debate. We also consider why the natural sciences tend to employ fewer reviewers and have lower rejection rates than do the social sciences. Our two recommendations are that a serious discussion of problems and alternatives to peer review should be started at all levels of psychology and that a science of research communication should be a priority, with psychologists as part of its advance guard because of their relevant substantive and methodological knowledge.
The Peer-Review and Editorial System: Ways to Fix Something That Might Be Broken
Authors: Schwartz Seth J. , Zamboanga Byron L.
Published: January 2009

The present article focuses on ways to make the peer-review and editorial process more efficient and more equitable for authors. In particular, we focus on the role of editors and action editors in the process of selecting and managing reviewers, balancing their own impressions of the manuscript with the reviewers' feedback, and rendering a fair and equitable editorial decision. We advance several recommendations to conserve reviewer time, provide authors with appropriate recourse when their papers are rejected unfairly, and expedite the processing of manuscripts that do not meet the standards of the journal to which they have been submitted.
What If Social Scientists Had Reviewed Great Scientific Works of the Past?
Authors: Trafimow David , Rice Stephen
Published: January 2009

One might question whether the great works in the history of science would get good reviews if subjected to the type of reviewing process to which psychologists are forced to submit their manuscripts. In some ways, behavioral scientists are too critical, and in other ways they are insufficiently so. To explore these issues, we imagine that great works from the history of nonsocial sciences were submitted for review in behavioral science journals and present simulated editor letters summarizing the comments of behavioral science reviewers. The philosophical underpinnings and justifications of the arguments are discussed, and recommendations for improved reviewing are offered.
Evaluation of Equol Function on Anti‐ or Prooxidant Status in vivo
Authors: Choi E.J.
Published: January 2009

ABSTRACT:  The present study was performed to investigate the effects of equol on oxidative stress and the antioxidant defense system in the livers of mice. Mice were orally administered equol at either 5 or 25 mg/kg body weight/day for 1, 3, or 7 wk. Equol administration significantly inhibited biomarkers of oxidative stress (thiobarbituric acid‐reactive substances value, carbonyl content, and serum 8‐OH‐dG) at all doses and for all durations of administration, and this phenomenon was most pronounced at 3 wk. Moreover, catalase and total superoxide dismutase (SOD) activities and their mRNA expression were significantly increased by equol. Although equol increased the glutathione peroxidase (GSH‐px) activity in mice treated with equol for 1 wk, long‐term administration of equol (7 wk) caused a decrease in the ratio of reduced/oxidized glutathione (GSH/GSSG) and the activities of GSH‐px and glutathione reductase (GR). Taken together, these results suggest that equol may act as an antioxidant through an inhibition of oxidative stress and stimulation of catalase and SOD, but can also cause prooxidant effects such as reduction of the GSH/GSSG ratio, depending on the treatment period.
Antioxidative Ability, Dioscorin Stability, and the Quality of Yam Chips from Various Yam Species as Affected by Processing Method
Authors: Liu Y.‐M. , Lin K.‐W.
Published: January 2009

ABSTRACT:  The antioxidative ability, stability of storage protein dioscorin, and the quality of fried yam chips from different cultivars of Chinese yams influenced by various processing treatments were investigated. Total phenolic content and DPPH free radical scavenging effect were found to be the highest in Mingchien (MC) and the lowest in Keelung (KL) yam. Following processing, freeze‐dried yams of all varieties showed the least decrease in total phenolic compounds and DPPH radical scavenging effect, while boiling caused the greatest decrease in both. Fresh yams of all varieties contained the highest dioscorin contents comparing with their counterparts. Boiling and deep‐frying caused severe protein denaturation resulting in loss of dioscorin solubility after purification. Freeze‐drying resulted in increase in protein surface hydrophobicity (So); nonetheless, it attained higher total phenol content, antioxidative capacity, and dioscorin stability of yams compared with other processing treatments. The peroxide values of all yam chips increased during the initial stage, then declined with advanced storage. Fracturability of all yam chips gradually decreased, due to the absorption of moisture, with increasing storage time.
Shear Rheology of Molten Crumb Chocolate
Authors: Taylor J.E. , Van Damme I. , Johns M.L. , Routh A.F. , Wilson D.I.
Published: January 2009

ABSTRACT:  The shear rheology of fresh molten chocolate produced from crumb was studied over 5 decades of shear rate using controlled stress devices. The Carreau model was found to be a more accurate description than the traditional Casson model, especially at shear rates between 0.1 and 1 s−1. At shear rates around 0.1 s−1 (shear stress approximately 7 Pa) the material exhibited a transition to a solid regime, similar to the behavior reported by Coussot (2005) for other granular suspensions. The nature of the suspension was explored by investigating the effect of solids concentration (0.20 < φ < 0.75) and the nature of the particles. The rheology of the chocolate was then compared with the rheology of (1) a synthetic chocolate, which contained sunflower oil in place of cocoa butter, and (2) a suspension of sugar of a similar size distribution (volume mean 15 μm) in cocoa butter and emulsifier. The chocolate and synthetic chocolate showed very similar rheological profiles under both steady shear and oscillatory shear. The chocolate and the sugar suspension showed similar Krieger–Dougherty dependency on volume fraction, and a noticeable transition to a stiff state at solids volume fractions above approximately 0.5. Similar behavior has been reported by Citerne and others (2001) for a smooth peanut butter, which had a similar particle size distribution and solids loading to chocolate. The results indicate that the melt rheology of the chocolate is dominated by hydrodynamic interactions, although at high solids volume fractions the emulsifier may contribute to the departure of the apparent viscosity from the predicted trend.
Development of a Risk‐Ranking Framework to Evaluate Potential High‐Threat Microorganisms, Toxins, and Chemicals in Food
Authors: Newsome R. , Tran N. , Paoli G.M. , Jaykus L.A. , Tompkin B. , Miliotis M. , Ruthman T. , Hartnett E. , Busta F.F. , Petersen B. , Shank F. , McEntire J. , Hotchkiss J. , Wagner M. , Schaffner D.W.
Published: January 2009

ABSTRACT:  Through a cooperative agreement with the U.S. Food and Drug Administration, the Institute of Food Technologists developed a risk‐ranking framework prototype to enable comparison of microbiological and chemical hazards in foods and to assist policy makers, risk managers, risk analysts, and others in determining the relative public health impact of specific hazard–food combinations. The prototype is a bottom‐up system based on assumptions that incorporate expert opinion/insight with a number of exposure and hazard‐related risk criteria variables, which are propagated forward with food intake data to produce risk‐ranking determinations. The prototype produces a semi‐quantitative comparative assessment of food safety hazards and the impacts of hazard control measures. For a specific hazard–food combination the prototype can produce a single metric: a final risk value expressed as annual pseudo‐disability adjusted life years (pDALY). The pDALY is a harmonization of the very different dose–response relationships observed for chemicals and microbes. The prototype was developed on 2 platforms, a web‐based user interface and an Analytica® model (Lumina Decision Systems, Los Gatos, Calif., U.S.A.). Comprising visual basic language, the web‐based platform facilitates data input and allows use concurrently from multiple locations. The Analytica model facilitates visualization of the logic flow, interrelationship of input and output variables, and calculations/algorithms comprising the prototype. A variety of sortable risk‐ranking reports and summary information can be generated for hazard–food pairs, showing hazard and dose–response assumptions and data, per capita consumption by population group, and annual p‐DALY.
Intra‐Aortic Balloon Counterpulsation for the Treatment of Myocardial Infarction Complicated by Acute Severe Heart Failure
Authors: Tsagalou Eleftheria P. , Anastasiou‐Nana Maria I. , Nanas John N.
Published: January 2009

Intractable heart failure (HF) remains a leading fatal complication of acute myocardial infarction (AMI). Intra‐aortic balloon pump (IABP) counterpulsation assists the failing left ventricle and accelerates the functional recovery of stunned myocardium. Despite its remarkable performance, the beneficial effects of the IABP in the setting of acute HF or cardiogenic shock complicating AMI have not been confirmed in a randomized clinical trial. Instead, large amounts of information have been collected in observational studies or in retrospective analyses of randomized trials of reperfusion strategies in patients with AMI. The strategy of “stabilize with IABP, treat with reperfusion, and transfer for complete revascularization” has, thus far, yielded the best outcomes, and every effort should be made to implement this strategy in all patients presenting with AMI and severe HF.
Carvedilol Produces Sustained Long‐Term Benefits: Follow‐Up at 12 Years
Authors: MacGregor John F. , Blake Wachter S. , Munger Mark , Stoddard Greg , Bristow Michael R. , Gilbert Edward M.
Published: January 2009

The authors measured long‐term outcomes of patients who initiated carvedilol between 1990 and 1992 to test the hypothesis that carvedilol produces sustained benefits in heart failure patients. The study population consisted of 57 patients who completed a carvedilol placebo‐controlled phase II trial. Patients were given open‐label carvedilol and were titrated to the maximum dose. Patients were assessed by serial multigated acquisition, echocardiography, and symptom scores. Survival was assessed for all patients and censored as of January 1, 2004. Survival for ischemic vs nonischemic patients was compared using the log‐rank test and further compared using Cox regression, controlling for covariates. Etiology of heart failure was ischemic in 15 patients and nonischemic in 42 patients. Median follow‐up was 12.9 years. Resting left ventricular ejection fraction (LVEF) and heart failure symptom scores improved at 4 months of treatment and were sustained at 24 months. Left ventricular internal diameter in systole (LVIDS) and left ventricular internal diameter in diastole decreased significantly at 4 and 8 months, respectively, and LVIDS continued to improve at 24 months. Overall mortality was 43% in nonischemic patients and 73% in ischemic patients. In a multivariate analysis, ischemic etiology and baseline LVEF were significant predictors of mortality. Carvedilol produces sustained improvements in left ventricular remodeling and symptoms. Long‐term survival is good, particularly in nonischemic patients.
Initial Emergency Department Systolic Blood Pressure Predicts Left Ventricular Systolic Function in Acute Decompensated Heart Failure
Authors: Styron Joseph F. , Jois‐Bilowich Preeti , Starling Randall , Hobbs Robert E. , Kontos Michael C. , Pang Peter S. , Peacock W. Frank
Published: January 2009

Ejection fraction (EF) is often unknown in patients who present with acute decompensated heart failure (ADHF). The objective of this study was to determine whether a patient’s systolic blood pressure is associated with their left ventricular EF. This study was a retrospective chart review of all patients admitted to an emergency department (ED) observation unit from January 2002 to December 2004. A low EF was defined as <40%. Among 475 patients, the median age was 72 years, 53% were men, 40% were white, 59% were black, and 59% had a low EF. Patients with low EFs were more likely male ( P<.0001), with prior congestive heart disease ( P<.0001), longer QRS duration ( P<.0001), left bundle branch block ( P<.0001), and higher B‐type natriuretic peptide ( P<.0001). The low EF group was less likely to have diabetes ( P<.0001). Adjusted odds ratios for an EF ≥40% were significant at all systolic blood pressure readings >120 mm Hg. Having an ED systolic BP >120 mm Hg is associated with significantly higher rates of preserved left ventricular systolic function in patients with ADHF.
On the Effect of External Bending Loads in Bolted Flange Joints
Authors: Bouzid Abdel-Hakim
Published: January 2009

Most current flange design methods use an equivalent pressure to treat bolted flange connections subjected to external bending loads. This oversimplified approach together with the lack of a proper assessment of the actual affected tightness make these methods inadequate for modern flange design. The substitution of the external applied moment by an equivalent pressure is excessively conservative and not realistic since it assumes that the achieved tightness is that of a gasket unloaded entirely to a minimum stress whereas in reality only a small section of it is, the rest of it is actually at a much higher stress. The successfulness of a valid analytical approach in yielding to an acceptable solution resides in its ability to account for the circumferential distribution of the gasket contact stress and its effect on leakage. This paper presents an analytical model based on the flexibility of the flange to treat flanges subjected to bending loads such as those produced by external moments and misalignments and capable of integrating leakage around the gasket circumference. The bolted joint sealing performance in the presence of such loads is evaluated using the new Pressure Vessel Research Council (PVRC) gasket constants Gb, a, and Gs, obtained from room temperature tightness (ROTT) tests. The analytical results including leakage predictions are validated by comparison to those obtained numerically by finite element analysis and experimentally on different size flanges. The overconservatism of the equivalent pressure is demonstrated.
One-Dimensional Moving Heat Source in a Hollow FGM Cylinder
Authors: Jabbari M. , Mohazzab A. H. , Bahtui A.
Published: January 2009

This paper presents the analytical solution of one-dimensional mechanical and thermal stresses for a hollow cylinder made of functionally graded material. The material properties vary continuously across the thickness, according to the power functions of radial direction. Temperature distribution is symmetric and transient. The thermal boundary conditions may include conduction, flux, and convection for inside or outside of a hollow cylinder. The thermoelasticity equation is transient, including the moving heat source. The heat conduction and Navier equations are solved analytically, using the generalized Bessel function. A direct method of solution of Navier equation is presented.
An Anisotropic Creep Damage Model for Anisotropic Weld Metal
Authors: Peravali S. , Hyde T. H. , Cliffe K. A. , Leen S. B.
Published: January 2009

Past studies from creep tests on uniaxial specimens and Bridgman notch specimens, for a P91 weld metal, showed that anisotropic behavior (more specifically transverse isotropy) occurs in the weld metal, both in terms of creep (steady-state) strain rate behavior and rupture times (viz., damage evolution). This paper describes the development of a finite element (FE) continuum damage mechanics methodology to deal with anisotropic creep and anisotropic damage for weld metal. The method employs a second order damage tensor following the work of Murakami and Ohno (1980, “A Continuum Theory of Creep and Creep Damage,” Creep in Structures, A. R. S. Ponter and D. R. Hayhurst, eds., Springer-Verlag, Berlin, pp. 422–444) along with a novel rupture stress approach to define the evolution of this tensor, taking advantage of the transverse isotropic nature of the weld metal, to achieve a reduction in the number of material constants required from test data (and hence tests) to define the damage evolution. Hill’s anisotropy potential theory is employed to model the secondary creep. The theoretical model is implemented in a material behavior subroutine within the general-purpose nonlinear FE code ABAQUS (ABAQUS User’s Manual, Version 6.6, 6006, Hibbitt, Karlsson and Sorenson, Inc., Providence, RI). The validation of the implementation against established isotropic continuum damage mechanics solutions for the isotropic case is described. A procedure for calibrating the multiaxial damage constants from notched bar test data is described for multiaxial implementations. Also described is a study on the effect of uniaxial specimen orientation on anisotropic damage evolution.
Trends and Cost Analysis of AWJ Operation at 600MPa Pressure
Authors: Hashish Mohamed
Published: January 2009

Increasing the pressure of abrasive waterjet, while fixing the jet power, increases the jet’s power density and thus the cutting speed may increase. This was observed for steel, aluminum, and stone cutting. It was also observed that the kerf taper is less for higher pressure jets. Increasing the pressure while keeping the jet diameter fixed will increase both the power and the power density. This will result in increased cutting speed and less taper. The operating cost of the abrasive waterjets process consists mainly of the costs of abrasives, nozzle wear, utility, and maintenance of equipment. The cost per unit length of material (specific cost) is determined based on the cutting speed. It was found that the main advantage of increasing pressure is increasing the cutting speed or reducing the abrasive consumption per unit time or unit length of cut. The highest savings are obtained when the speed is maximized by increasing the pressure and the abrasive flow rate. Several study cases were addressed in this paper using assumptions and simple models to generalize the analysis. The analysis indicates that increasing the pressure from 400MPato600MPa may result in cost per unit length saving of over 30%.
Numerical Calculation of Shear Stress Distribution on the Inner Wall Surface of CANDU Reactor Feeder Pipe Conveying Two-Phase Coolant
Authors: Jo Jong Chull , Kang Dong Gu , Roh Kyung Wan
Published: January 2009

Two-phase flow fields inside feeder pipes of a CANada Deuterium Uranium (CANDU) reactor have been simulated numerically using a computational fluid dynamics (CFD) code to calculate the shear stress distribution, which is the most important factor to be considered in predicting the local areas of feeder pipes highly susceptible to flow-accelerated corrosion (FAC)-induced wall thinning. The CFD approach with schemes used in this study to simulate the turbulent flow situations inside the CANDU feeder pipes has been verified by showing a good agreement between the investigation results for the failed feedwater pipe at Surry Unit 2 plant in the U.S. and the CFD calculation. Sensitivity studies of the three geometrical parameters such as angle of the first and second bends, length of the first span between the grayloc hub and the first bend, and length of the second span between the first and second bends had already been performed. In this study, the effects of void fraction of the primary coolant coming out from the exit of pressure tubes containing nuclear fuel on the fluid shear stress distribution at the inner surface of the feeder pipe wall have been investigated to find out the local areas of feeder pipes conveying a two-phase coolant, which are highly susceptible to FAC-induced wall thinning. From the results of the CFD analysis, it is seen that the local regions of feeder pipes of the operating CANDU reactors in Korea, on which the wall thickness measurements have been performed so far, do not coincide with the worst regions predicted by the present CFD analysis, which is the connection region of straight and bend pipes near the inlet part of the bend intrados. Finally, based on the results of the present CFD analysis, a guide to the selection of the weakest local positions where the measurement of wall thickness should be performed with higher priority has been provided.
Plastic Collapse Load for Vessel With External Flaw Simultaneously Subjected to Internal Pressure and External Bending Moment: Experimental and FEA Results
Authors: Konosu Shinji , Kano Masato , Mukaimachi Norihiko , Komura Hiroyuki , Takada Hiroyuki
Published: January 2009

This paper is based on work done to establish the validity of a simple engineering approach to assess plastic collapse for a vessel with a local thin area (LTA). The approach is based on a recently developed p-M (internal pressure ratio and external bending moment ratio) diagram, which is an easy way to visualize the status of a vessel with a LTA simultaneously subjected to internal pressure, p and external bending moment, M due to earthquake, etc. If the assessment point (Mr,pr) lies inside the p-M line, the vessel with the LTA is judged to be safe. Numerous experiments and finite element analyses for a cylinder with an external flaw were conducted under (1) pure internal pressure, (2) pure external bending moment, and (3) subjected simultaneously to both internal pressure and external bending moment, in order to determine the plastic initiation load and plastic collapse load by applying the twice-elastic slope (TES) as recommended by ASME. It has been clarified that the collapse (TES) loads are similar to those calculated under the proposed p-M line based on the measured yield stress. The p-M line adopted in the Ibaraki fitness for service (FFS) rule based on the specified minimum yield stress with a safety factor of 1.5 indicates that the safety margin for the plastic initiation loads at LTA is about 1.0–3.0, about 1.5–4.0 for the TES loads at LTA, and 2.5–6.5 for the plastic instability (break) loads.
Modeling of Size Effect on Tensile Flow Stress of Sheet Metal in Microforming
Authors: Leu Daw-Kwei
Published: January 2009

This investigation considers the size effect on the deformation behavior of simple tension in microforming and thus proposes a simple model of the tensile flow stress of sheet metal. Experimental results reveal that the measure of the flow stress can be represented as a hyperbolic function tanh(T/D), which is a function of T/D (sheet thickness/grain size). The predicted flow stress agrees very well with the published experiment. Notably, a specimen with smaller grains has lower normalized flow stress for a given T/D. Since the material properties of the macroscale specimen do not pertain to the microscale, a critical condition (T/D)c that distinguishes the macroscale from the microscale in the tensile flow stress is subsequently proposed, based on the “affected zone” model, the pile-up theory of dislocations, and the Hall–Petch relation. The distribution of the predicted (T/D)c is similar to the experimental finding that the (T/D)c decreases as the grain size increases. However, the orientation-dependent factor β is sensitive to (T/D)c. Hence, further study of the orientation-dependent factor β is necessary to obtain a more accurate (T/D)c and, thus, to evaluate and understand better the tensile flow stress of sheet metal in microforming.
Applicable Contact Force Models for the Discrete Element Method: The Single Particle Perspective
Authors: Kruggel-Emden H. , Wirtz S. , Scherer V.
Published: January 2009

Several processes in nature as well as many industrial applications involve static or dynamic granular materials. Granulates can adopt solid-, liquid-, or gaslike states and thereby reveal intriguing physical phenomena not observable in its versatility for any other form of matter. The frequent occurrence of phase transitions and the related characteristics thereby strongly affect their processing quality and economics. This situation demands for prediction methods for the behavior of granulates. In this context simulations provide a feasible alternative to experimental investigations. Several different simulation approaches are applicable to granular materials. The time-driven discrete element method turns out to be not only the most complex but also the most general simulation approach. Discrete element simulations have been used in a wide variety of scientific fields for more than 30 years. With the tremendous increase in available computer power, especially in the past years, the method is more and more developing to the state of the art simulation technique for granular materials not only in science but also in industrial applications. Several commercial software packages utilizing the time-driven discrete element method have emerged and are becoming more and more popular within the engineering community. Despite the long time of usage of the time-driven discrete element method, model advances derived and theoretical and experimental studies performed in the different branches of application lack harmonization. They thereby provide potential for improvements. Therefore, the scope of this paper is a review of methods and models for contact forces based on theoretical considerations and experimental data from literature. Particles considered are of spherical shape. Through model advances it is intended to contribute to a general enhancement of simulation techniques, which help improve products and the design of the related equipment.
Friction Stir Welding Heat Transfer: Quasisteady Modeling and Its Validation
Authors: Perivilli Satish , Peddieson John , Cui Jie
Published: January 2009

A quasisteady approach to friction stir welding (FSW) heat transfer modeling is proposed and implemented using FLUENT. An idealized model of the mechanical dissipation heating in FSW is employed. Selected numerical predictions based on the model are shown to capture most of the features of corresponding experimental data available in literature. It is concluded that the quasisteady formulation (due to its simplicity and moderate usage of computational resources) is an attractive alternative to more computationally intensive unsteady approaches to FSW modeling under some circumstances.
Nanofluids: From Vision to Reality Through Research
Authors: Choi Stephen U. S.
Published: January 2009

Nanofluids are a new class of nanotechnology-based heat transfer fluids engineered by dispersing and stably suspending nanoparticles with typical length on the order of 1–50 nm in traditional heat transfer fluids. For the past decade, pioneering scientists and engineers have made phenomenal discoveries that a very small amount (<1 vol %) of guest nanoparticles can provide dramatic improvements in the thermal properties of the host fluids. For example, some nanofluids exhibit superior thermal properties such as anomalously high thermal conductivity at low nanoparticle concentrations, strong temperature- and size-dependent thermal conductivity, a nonlinear relationship between thermal conductivity and concentration, and a threefold increase in the critical heat flux at a small particle concentration of the order of 10 ppm. Nanofluids are of great scientific interest because these unprecedented thermal transport phenomena surpass the fundamental limits of conventional macroscopic theories of suspensions. Therefore, numerous mechanisms and models have been proposed to account for these unexpected, intriguing thermal properties of nanofluids. These discoveries also show that nanofluids technology can provide exciting new opportunities to develop nanotechnology-based coolants for a variety of innovative engineering and medical applications. As a result, the study of nanofluids has emerged as a new field of scientific research and innovative applications. Hence, the subject of nanofluids is of great interest worldwide for basic and applied research. This paper highlights recent advances in this new field of research and shows future directions in nanofluids research through which the vision of nanofluids can be turned into reality.
Heat Transfer Characterizations of Heat Pipe in Comparison With Copper Pipe
Authors: Ting Chen-Ching , Lee Jing-Nang , Chen Chien-Chih
Published: January 2009

The article presents some significant experimental data for studying the heat transfer behavior of heat pipe, which will further help the cooling efficiency improvement of the heat pipe cooler. It is well known that the heat pipe owns the extreme large heat conductivity and is often integrated with cooling plates for CPU cooling. The heat pipe uses special heat transfer techniques to obtain extremely large heat conductivity, which are the inside liquid evaporation for heat absorption and the inside microstructural capillarity for condensation. These special techniques yield the instant heat transfer from the heat source to the remote side directly, but the special heat transfer behavior is changed due to the integration with cooling plates. The destroyed heat transfer behavior of the heat pipe causes the cooling efficiency of the heat pipe cooler to be not able to reach a predicted good value. To improve the cooling efficiency of the heat pipe cooler we recover the original heat transfer behavior of the heat pipe integrated with cooling plates. This work first built a CPU simulator in accordance with the ASTM standard for heating the heat pipe, then uses the color schlieren technique to visualize the sequent heat flux nearby the heat pipe and the infrared thermal camera for quantitative temperature measurements synchronously. The result shows that the heat flux first appears at the opposite side from the heat source and there exhibits also the highest temperature. This is different from the heat transfer behavior of the copper pipe. Another very interesting result is that the heat flux of the cooling plate nearest to the heat source is first viewed than the others, which is similar to the integration with the copper pipe.