bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chronic toxicity of the synthetic hormone 17α-Ethinylestradiol toChironomus tentansandHyalella azteca
Authors: Dussault Éve B , Balakrishnan Vimal K , Solomon Keith R , Sibley Paul K 
Published: July 2008

AbstractThe chronic toxicity of the synthetic hormone 17α-ethinylestradiol (EE2) was investigated in two benthic invertebrates, the midge Chironomus tentans and the freshwater amphipod Hyalella azteca, in life-cycle water-only assays. In C. tentans, a 50% decrease in emergence was observed at a concentration of 1.5 mg/L; emergence was a more sensitive endpoint than survival, growth, or biomass. Reproduction was not significantly affected by EE2 exposure until a concentration of 3.1 mg/L, where emergence, and therefore reproduction, did not occur. In contrast, reproduction was the most sensitive endpoint in H. azteca (50% decrease in reproduction observed at a concentration of 0.36 mg/L). The sensitivity of the F1 generation to EE2 was also investigated with H. azteca, but was not different from the F0 generation. The data from the present study were combined with those from previous 10-d toxicity assays, to derive acute to chronic toxicity ratios (ACRs) for EE2. The ACRs calculated for EE2 were 13 for C. tentans and 16 for H. azteca, indicating that the application factors currently used in ecological risk assessment for the derivation of chronic toxicity are protective and conservative for these organisms. The results of the present study suggest that chronic toxicity was not mediated by disruption of endocrine pathways. Using a hazard quotient approach, the risk associated with sublethal exposure to EE2 was &lt;&lt; 1 for H. azteca and C. tentans, indicating that adverse effects are not expected, and that environmental exposure to EE2 likely poses a low risk to benthic invertebrates.
Neighborhood Psychosocial Hazards and Cardiovascular Disease: The Baltimore Memory Study
Authors: Augustin Toms , Glass Thomas A. , James Bryan D. , Schwartz Brian S. 
Published: July 2008

Objectives. We examined associations between cardiovascular disease and neighborhood psychosocial hazards, such as violent crime, abandoned buildings, and signs of incivility, to evaluate whether features of place are associated with older adult health. Methods. We analyzed first-visit data from the Baltimore Memory Study of randomly selected residents aged 50 to 70 years (n=1140) of 65 contiguous neighborhoods in Baltimore, Maryland. We looked for associations between self-reports of history of selected cardiovascular diseases and scores on the 12-item neighborhood psychosocial hazards scale. Results. After adjustment for established individual risk factors for cardiovascular disease, residents in neighborhoods with scores in the highest quartile of the psychosocial hazards scale had more than 4 times higher odds of a history of myocardial infarction and more than 3 times higher odds of myocardial infarction, stroke, transient ischemic attack, or intermittent claudication compared with residents living in neighborhoods scoring in the lowest quartile. Conclusions. Neighborhood psychosocial hazards were significantly associated with self-reported cardiovascular disease after adjustment for individual-level risk factors. This is consistent with the hypothesis that environmental stress plays a role in the etiology of cardiovascular disease.
Intramolecular Dipole Coupling and Depolarization in Self‐Assembled Monolayers
Authors: Sushko Maria L. , Shluger Alexander L. 
Published: July 2008

AbstractQuantum mechanical and classical atomistic computational methods are used to simulate the chain‐length dependence of depolarization effects in S(CH2)n−1CH3 and S(CH2)n−1COOH self‐assembled monolayers on gold (111) surface. These calculations show that due to weak cooperative effects, the electrostatic properties of alkanethiol monolayers are well described by the gas phase dipole moments of the molecules. However, depolarization in monolayers with the molecules carrying head‐ and tail‐group dipoles, such as COOH‐terminated monolayers, strongly depends on the degree of intramolecular dipole coupling. Thus the electrostatic properties of self‐assembled monolayers can be engineered by changing the length of the aliphatic spacer between the polar groups. The transition from strong to weak coupling regime was found to be accompanied by the change in the sign of the asymptotic value of electrostatic potential above the surface of the monolayers and hence in the sign of the metal work function change. Therefore, the use of weakly polarizable spacers between the polar groups inside the molecules forming the SAM is beneficial for accessing a wider range of work‐function changes.
Gold Nanoparticle–Colloidal Carbon Nanosphere Hybrid Material: Preparation, Characterization, and Application for an Amplified Electrochemical Immunoassay
Authors: Cui Rongjing , Liu Chang , Shen Jianming , Gao Di , Zhu Jun‐Jie , Chen Hong‐Yuan 
Published: July 2008

AbstractA rapid microwave‐hydrothermal method has been developed to prepare monodisperse colloidal carbon nanospheres from glucose solution, and gold nanoparticles (AuNPs) are successfully assembled on the surface of the colloidal carbon nanospheres by a self‐assembly approach. The resulting AuNP/colloidal carbon nanosphere hybrid material (AuNP/C) has been characterized and is expected to offer a promising template for biomolecule immobilization and biosensor fabrication because of its satisfactory chemical stability and the good biocompatibility of AuNPs. Herein, as an example, it is demonstrated that the as‐prepared AuNP/C hybrid material can be conjugated with horseradish peroxidase‐labeled antibody (HRP‐Ab2) to fabricate HRP‐Ab2‐AuNP/C bioconjugates, which can then be used as a label for the sensitive detection of protein. The amperometric immunosensor fabricated on a carbon nanotube‐modified glass carbon electrode was very effective for antibody immobilization. The approach provided a linear response range between 0.01 and 250 ng mL−1 with a detection limit of 5.6 pg mL−1. The developed assay method was versatile, offered enhanced performances, and could be easily extended to other protein detection as well as DNA analysis.
Synthesis of Hierarchically Structured Metal Oxides and their Application in Heavy Metal Ion Removal
Authors: Hu Jin‐Song , Zhong Liang‐Shu , Song Wei‐Guo , Wan Li‐Jun 
Published: July 2008

AbstractHierarchically structured metal oxides have two or more levels of structure. Their nanometer‐sized building blocks provide a high surface area, a high surface‐to‐bulk ratio, and surface functional groups that can interact with, e.g., heavy metal ions. Their overall micrometer‐sized structure provides desirable mechanical properties, such as robustness, facile species transportation, easy recovery, and regeneration. In combination these features are suitable for the removal of heavy metal ions from water. Several general synthesis routes for the fabrication of metal oxides with various morphologies and hierarchical structures are discussed including soft and hard template‐assisted routes. These routes are general, reliable, and environmentally friendly methods to prepare transition and rare earth metal oxides, including cobalt oxide, iron oxide, and ceria. As‐prepared hierarchically structured metal oxides show excellent adsorption capacities for AsV and CrVI ions in water.
Statistical‐based monitoring of multivariate non‐Gaussian systems
Authors: Liu Xueqin , Xie Lei , Kruger Uwe , Littler Tim , Wang Shuqing 
Published: July 2008

AbstractThe monitoring of multivariate systems that exhibit non‐Gaussian behavior is addressed. Existing work advocates the use of independent component analysis (ICA) to extract the underlying non‐Gaussian data structure. Since some of the source signals may be Gaussian, the use of principal component analysis (PCA) is proposed to capture the Gaussian and non‐Gaussian source signals. A subsequent application of ICA then allows the extraction of non‐Gaussian components from the retained principal components (PCs). A further contribution is the utilization of a support vector data description to determine a confidence limit for the non‐Gaussian components. Finally, a statistical test is developed for determining how many non‐Gaussian components are encapsulated within the retained PCs, and associated monitoring statistics are defined. The utility of the proposed scheme is demonstrated by a simulation example, and the analysis of recorded data from an industrial melter. © 2008 American Institute of Chemical Engineers AIChE J, 2008
Fault detection in nonlinear continuous‐time systems with uncertain parameters
Authors: Lin Youdong , Stadtherr Mark A. 
Published: July 2008

AbstractIn model‐based fault diagnosis for dynamic systems with uncertain parameters, an envelope of all fault‐free behaviors can be determined from the model and used as a reference for detecting faults. We demonstrate here a method for generating an envelope that is rigorously guaranteed to be complete, but without significant overestimation. The method is based on an interval approach, but uses Taylor models to reduce the overestimation often associated with interval methods. To speed fault detection, a method that uses bounded‐error measurement data and a constraint propagation procedure is proposed for shrinking the envelope. Several fault detection scenarios involving nonlinear, continuous‐time systems are used to evaluate this approach. © 2008 American Institute of Chemical Engineers AIChE J, 2008
Optimization of two‐dimensional flows with homogeneous and heterogeneously catalyzed gas‐phase reactions
Authors: Minh H. D. , Bock H. G. , Tischer S. , Deutschmann O. 
Published: July 2008

AbstractChemically reacting gaseous flows in catalytic monoliths are numerically investigated to mathematically optimize product yields by the variation of operating conditions and catalyst loading. The fluid dynamics of the single monolith channel is modeled by the two‐dimensional boundary layer equations (BLEs), a system of parabolic partial differential equations (PDEs) with highly nonlinear boundary conditions arising from the coupling of surface reactions with the reactive flow field inside the channel. The surface and gas‐phase chemical reactions are described by large elementary‐step reaction mechanisms. An optimal control problem is formulated with the wall temperature, the catalytic active surface area, and the inlet gas composition and flow parameters as control variables. The newly developed approach and numerical code are applied for the optimization of the oxidative dehydrogenation of ethane to ethylene over platinum at high temperatures and short contact times. The ethylene yield can be significantly increased by choosing the optimal operating conditions. Furthermore, the analysis of the behavior of the reactor at optimized conditions leads to a better understanding of the interaction of physics and chemistry in the catalytic monolith. © 2008 American Institute of Chemical Engineers AIChE J, 2008
Design of a thermally balanced membrane reformer for hydrogen production
Authors: Simakov David S. A. , Sheintuch Moshe 
Published: July 2008

AbstractHydrogen production by autothermal methane steam reforming in a catalytic fixed bed membrane reactor has been analyzed and simulated. The two‐compartment reactor indirectly couples the endothermic steam reforming with methane oxidation, while hydrogen is separated by a permselective Pd membrane. Simulations of the reactor, using published kinetics, map the acceptable domain of operation and the optimal set of operating parameters. The simulations exhibit slow‐moving thermal fronts and the steady‐state operation domains bounded by stationary fronts, separating domains of upstream and downstream‐moving fronts. Front velocity depends on thermal coupling and hydrogen separation. An analytical approximation for the thermal front velocity in a thermally balanced reactor has been developed. © 2008 American Institute of Chemical Engineers AIChE J, 2008
Heritabilities of somatotype components in a population from rural Mozambique
Authors: Saranga Sílvio Pedro José , Prista António , Nhantumbo Leonardo , Beunen Gaston , Rocha Jorge , Williams‐Blangero Sarah , Maia José A. 
Published: July 2008

AbstractThere have been few genetic studies of normal variation in body size and composition conducted in Africa. In particular, the genetic determinants of somatotype remain to be established for an African population. (1) To estimate the heritabilities of aspects of somatotype and (2) to compare the quantitative genetic effects in an African population to those that have been assessed in European and American populations. The sample composed of 329 subjects (173 males and 156 females) aged 7–17 years, belonging to 132 families. The sibships in the sample ranged in size from two to seven individuals. All sampled individuals were residents of the Calanga region, an area located to the north of Maputo in Mozambique. Somatotype was assessed using the Heath‐Carter technique. Herit abilities were estimated using SAGE software. Moderate heritabilities were determined for each trait. Between 30 and 40% of the variation in each somatotype measure was attributable to genetic factors. The heritability of ectomorphy was 31%. Mesomorphy was similarly moderately heritable, with ∼30% of the variationattributable to genetic factors. The heritability of endomorph was higher in the Calanga population (h2 = 0.40). Quantitative genetic analyses of somatotype variation among siblings indicate that genetic factors significantly influence endomorphy, mesomorhpy, and ectomorphy. However, environmental factors also have significant effects on the variation in physique present in the population of Calanga. Lack of proper nutrition, housing, medical assistance, and primary health care, together with very demanding and sex‐specific daily chores may contribute to the environmental effects on these traits. Am. J. Hum. Biol., 2008. © 2008 Wiley‐Liss, Inc.
National trends in silicosis mortality in the United States, 1981–2004
Authors: Bang Ki Moon , Attfield Michael D. , Wood John M. , Syamlal Girija 
Published: July 2008

AbstractBackgroundThis article describes trends in mortality with silicosis and identifies industries and occupations with elevated silicosis mortality.MethodsA total of 6,326 deaths with silicosis for 1981–2004 were analyzed for trends and association with occupation and industry. Annual mortality rates were age‐adjusted to the U.S. Year 2000 population. A linear regression model was used for analyzing mortality trends. Proportionate mortality ratios (PMRs) were based on 1,440 deaths with information on usual industry and occupation.ResultsOverall age‐adjusted mortality rates per million declined from 2.4 in 1981 to 0.7 in 2004. Industries having significantly elevated PMRs for silicosis included mining and quarrying. Occupations with elevated PMRs included those associated with metal and mineral processing.ConclusionsThe results suggest that considerable progress has been made towards elimination of this preventable disease. However, about 30 silicosis deaths per year have been recorded since 1995 among those of working age, warranting continued efforts to effectively limit workplace exposures. Am. J. Ind. Med. 51:633–639, 2008. Published 2008 Wiley‐Liss, Inc.
Just in the wrong place…?: Geographic tools for occupational injury/illness surveillance
Authors: Neff Roni A. , Curriero Frank C. , Burke Thomas A. 
Published: July 2008

AbstractBackgroundGeographic analysis is now integral to public health surveillance, but has been underused for occupational injury/illness.MethodsMapping and spatial statistics are used to examine national county‐level mean establishment Lost Workday Injury/Illness (LWDII) rates in the Occupational Safety and Health Administration (OSHA) Data Initiative (ODI), 1997–2001. The following questions are explored: Does occupational injury/illness vary geographically at the county level?; Does variation remain after accounting for industry hazard?; Where are rates higher or lower than expected?ResultsThe methods provide evidence of geographic variation in nonfatal occupational injury/illness rates, including after adjusting for industry hazard.ConclusionsGeographic analyses can improve intervention targeting, suggest risk factors for investigation, and make the case for targeting resources to prevention in hard‐hit areas, as well as improving ongoing surveillance. Am. J. Ind. Med. 51:680–690, 2008. Published 2008 Wiley‐Liss, Inc.
Postpartum recuperation in primiparous rhesus macaques and development of their infants
Authors: Mas‐Rivera Adaris , Bercovitch Fred B. 
Published: July 2008

AbstractFemale primates endure great costs during pregnancy and lactation. Some studies have been conducted on exploring these; however, information on how maternal condition before conception influences maternal postpartum recuperation and infant development are not well known, especially in primipares. This 2‐year investigation explored how maternal condition, maternal foraging time and alert time, and infants' time on nipple influenced postpartum recovery of primiparous rhesus macaques, as well as their infant's development during the first 3 months postpartum. The study was conducted on 11 female rhesus macaques (Macaca mulatta) living at the Caribbean Primate Research Center, Sabana Seca Field Station, Puerto Rico. Infant survivorship and development were not influenced by maternal age at first parturition or by the infants' time on the nipple. Infant development and maternal recovery were influenced by maternal condition before conception. Older primipares demonstrated greater postpartum recuperation. Maternal postpartum recuperation was not influenced by maternal feeding time or time the infant spent on the nipple. Maternal recuperation was negatively correlated with increased vigilance (alert time). Am. J. Primatol. 70:1047–1054, 2008. © 2008 Wiley‐Liss, Inc.
Poly(lactic acid) properties as a consequence of poly(butylene adipate‐co‐terephthalate) blending and acetyl tributyl citrate plasticization
Authors: Coltelli Maria‐Beatrice , Maggiore Irene Della , Bertoldo Monica , Signori Francesca , Bronco Simona , Ciardelli Francesco 
Published: July 2008

AbstractThis study was aimed at the modulation of poly(lactic acid) (PLA) properties by the addition of both a low‐molecular‐weight plasticizer, acetyl tributyl citrate (ATBC), and a biodegradable aliphatic–aromatic copolyester, poly(butylene adipate‐co‐terephthalate) (PBAT). PLA/PBAT, PLA/ATBC, and PLA/PBAT/ATBC mixtures with 10–35 wt % ATBC and/or PBAT were prepared in a discontinuous laboratory mixer, compression‐molded, and characterized by thermal, morphological, and mechanical tests to evaluate the effect of the concentration of either the plasticizer or copolyester on the final material flexibility. Materials with modulable properties, Young's modulus in the range 100–3000 MPa and elongation at break in the range 10–300%, were obtained. Moreover, thermal analysis showed a preferential solubilization of ATBC in the PBAT phase. Gas permeability tests were also performed to assess possible use in food packaging applications. The results are discussed with particular emphasis toward the effects of plasticization on physical blending in the determination of the phase morphology and final properties. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Thermal stability and ablation properties of silicone rubber composites
Authors: Kim Eung Soo , Kim Eun Jeong , Shim Jea Hun , Yoon Jin‐San 
Published: July 2008

AbstractEffects of incorporation of clay and carbon fiber (CF) into a high temperature vulcanized (HTV) silicone rubber, i.e., poly(dimethylsiloxane) (PDMS) containing vinyl groups, on its thermal stability and ablation properties were explored through thermogravimetric analyses (TGA) and oxy‐acetylene torch tests. Natural clay, sodium montmorillonite (MMT), was modified with a silane compound bearing tetra sulfide (TS) groups to prepare MMTS4: the TS groups may react with the vinyl groups of HTV and enhance the interfacial interaction between the clay and HTV. MMTS4 layers were better dispersed than MMT layers in the respective composites with exfoliated/intercalated coexisting morphology. According to TGA results and to the insulation index, the HTV/MMTS4 composite was more thermally stable than HTV/MMT. However, addition of CF to the composites lowered their thermal stability, because of the high thermal conductivity of CF. The time elapsed for the composite specimen, loaded with a constant weight, to break off after the oxy‐acetylene flame bursts onto the surface of the specimen was employed as an index for an integrated assessment of the ablation properties, simultaneously taking into consideration the mechanical strength of the char and the rate of decomposition. The elapsed time increased in the order of: HTV < HTV/CF ≈ HTV/MMTS4 < HTV/CF/MMTS4 ≈ HTV/MMT < HTV/CF/MMT. This order was different from the increasing order of the thermal stability determined by TGA results and the insulation index. The decreased degree of crosslinking of the composites with MMTS4 compared with that of the composite with MMT may be unfavorable for the formation of a mechanically strong char and could lead to early rupture of the HTV/MMTS4 specimen. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
The susceptibility of mental accounting principles to evaluation mode effects
Authors: Chatterjee Subimal , Heath Timothy B. , Min Junhong 
Published: July 2008

AbstractThe present research shows that the predictions and outcomes of mental‐accounting tests depend on whether preferences are measured separately (one at a time) or jointly (comparatively). Across five studies, we show that joint evaluation weakens some decision biases (the theater ticket problem, the calculator and jacket problem), but exacerbates others (the basketball game problem). Joint evaluations serve as a check on whether people think the answers they give in separate evaluations make sense or require adjustment. We discuss how the findings impact (1) tests of mental accounting predictions (between vs. within subjects designs), and (2) the normative status of mental accounting. Copyright © 2008 John Wiley & Sons, Ltd.
Tumorigenesis and neurodegeneration: two sides of the same coin?
Authors: Staropoli John F. 
Published: July 2008

AbstractDysregulation of genes that control cell‐cycle progression and DNA repair is a hallmark of tumorigenesis. It is becoming increasingly apparent, however, that these defects also contribute to degeneration of post‐mitotic neurons under certain conditions. The gene for ataxia‐telangiectasia mutated (ATM) is a prototype for this dual mechanism of action, with loss‐of‐function mutations causing not only selective degeneration of cerebellar neurons but also increased susceptibility to breast cancer and hematologic malignancy. Increased dosage of amyloid precursor protein in Down syndrome (trisomy 21) predisposes to dementia of Alzheimer type and may also contribute to acute leukemia and transient myeloproliferative disorder. The gene parkin, loss‐of‐function mutations in which account for about half of cases of early‐onset Parkinson disease, has been identified as a candidate tumor suppressor gene by several groups. Parkin is deleted or downregulated in several tumor types, and its re‐expression sensitizes derivative cell lines to inhibitors of cell‐cycle progression. The overlap of molecular pathways implicated in cancer and neurodegeneration challenges long‐held notions about differentiated cellular states and may open the door to novel therapeutic approaches to both groups of disorders. BioEssays 30:719–727, 2008. © 2008 Wiley Periodicals, Inc.