bluuebunny/crossref_metadata_2025 huggingface dataset:
Biomedical meetings and biomedical journals: Vive la difference et vive la compagnie
Authors: Roth Jesse
Published: October 2010

Why do we continue to gather to meet to exchange medical knowledge more than 500 years after the invention of the printing press, 100 years after the telephone, and 20 years after the widespread use of email? We, the human race, have been transmitting information by multimedia—voice, face, and body language—into each other's ears and eyes (and noses) in caves around fires, at work, and on the trail, since well over 100 000 years ago. That communication is built on a foundation shared with many other primates and non‐primate mammals. The origins of this communication are hundreds of millions of years old.

Each newly input bit of this type of communication often needs to be processed immediately and responded to appropriately (food, hug, love, hit, bite, fight, and flight). The brain has had all this evolutionary time to build a complex, rich network of neurons to take it all in immediately, deal with it speedily, and save it for guidance in the future. (Also, ‘re‐play’ is not usually a choice.)

Writing is only 5000 years old and comes in through only the eyes. (The ears and nose are excluded from these communications.) The earliest surviving paintings, the predecessors of writing, are less than 30 000 years old and are an exclusive product of human evolution. The brain has had less time to build a rich response centre. Re‐reading is common. Only in a minority of instances (e.g. STOP sign, High Voltage) is an immediate response demanded. In essence, the two distinct modes of communication complement one another. Vive la difference. Vive la compagnie. Copyright © 2010 John Wiley & Sons, Ltd.

Commentary

We witnessed this complementarity at the recent Laniado Hospital/Bildirici Diabetes Center meeting in Israel. The public presentations from the speaker's platform stirred the minds and souls of the audience. We remember the presenter, we recall the overall message (but not the details), and we were emotionally moved by what we heard. Now we are publishing these papers in a medical journal to use the other mode of communication—the written word (cool, slow, reader's convenience, skip, and re‐play). Each alone is good—the two together produce an unexplained but exhilarating synergy and a long‐term meld of the warm emotion and cool reason. Copyright © 2010 John Wiley & Sons, Ltd.
Association of cognitive performance with the metabolic syndrome and with glycaemia in middle‐aged and older European men: the European Male Ageing Study
Authors: Tournoy Jos , Lee David M. , Pendleton Neil , O'Neill Terence W. , O'Connor Daryl B. , Bartfai Gyorgy , Casanueva Felipe F. , Finn Joseph D. , Forti Gianni , Giwercman Aleksander , Han Thang S. , Huhtaniemi Ilpo T. , Kula Krzysztof , Lean Michael E. J. , Moseley Carly M. , Punab Margus , Silman Alan J. , Vanderschueren Dirk , Wu Frederick C. W. , Boonen Steven ,   and the EMAS study group
Published: October 2010

Background and aims

Metabolic syndrome has been reported to have adverse effects on cognition although the results are conflicting. We investigated the association between metabolic syndrome and cognitive function in a population sample of middle‐aged and older European men and whether any observed association could be explained by lifestyle or other confounding factors.

Methods

A total of 3369 men in the 40‐ to 79‐year age group were recruited from population registers in eight centres for participation in the European Male Ageing Study. The subjects completed a questionnaire instrument and several cognitive function tests including the Rey–Osterrieth Complex Figure test, the Camden Topographical Recognition Memory test and the Digit Symbol Substitution Test. Metabolic syndrome data were assessed at an invited visit and metabolic syndrome was defined by the National Cholesterol Education Program's Adult Treatment Panel‐III criteria.

Associations between cognitive performance and metabolic syndrome were explored using linear regression.

Results

Complete cognitive and metabolic syndrome data from 3152 subjects were included in the analysis, of whom 1007 (32%) fulfilled criteria for metabolic syndrome. After adjustment for putative health and lifestyle confounders, no significant associations were found between any of the cognitive function scores and metabolic syndrome or between cognitive performance and high‐sensitivity C‐reactive protein. Analysis of the individual metabolic syndrome factors, however, revealed an inverse association between the level of glucose and cognitive performance.

Conclusions

Metabolic syndrome was not associated with cognitive impairment in this population. Of the individual components of the syndrome, diabetes was associated with poorer performances in memory, executive functions and processing speed, associations that warrant further investigation. Copyright © 2010 John Wiley & Sons, Ltd.
Simultaneous determination of GHB and EtG in hair using GCMS/MS
Authors: Paul R. , Tsanaclis L. , Kingston R. , Berry A. , Guwy A.
Published: October 2010

A gas chromatographic tandem mass spectrometric (GCMS/MS) method for simultaneously determining trace concentrations of gamma‐hydroxybutyrate (GHB) and ethyl glucuronide (EtG) in hair has been developed. Multiple reaction monitoring (MRM) was used to detect precursor and product ions of GHB, (233 and 147) and EtG (261 and 143) following anion exchange solid phase extraction and derivatization with N,O‐bis[trimethylsilyl]trifluoroacetamide (BSTFA). Deuterated standards of GHB and EtG were used as internal standards. The assay produced excellent linearity (r2 > 0.99) and sensitivity. The lower limit of quantitation (LLOQ) was 10 pg/mg for EtG assuming a 20 mg hair sample. The method has been used to investigate cases of suspected drug facilitated assault as well as being used to identify heavy alcohol consumption in a group of volunteers. Copyright © 2010 John Wiley & Sons, Ltd.
Far from solved: A perspective on what we know about early mechanisms of left–right asymmetry
Authors: Vandenberg Laura N. , Levin Michael
Published: October 2010

Consistent laterality is a crucial aspect of embryonic development, physiology, and behavior. While strides have been made in understanding unilaterally expressed genes and the asymmetries of organogenesis, early mechanisms are still poorly understood. One popular model centers on the structure and function of motile cilia and subsequent chiral extracellular fluid flow during gastrulation. Alternative models focus on intracellular roles of the cytoskeleton in driving asymmetries of physiological signals or asymmetric chromatid segregation, at much earlier stages. All three models trace the origin of asymmetry back to the chirality of cytoskeletal organizing centers, but significant controversy exists about how this intracellular chirality is amplified onto cell fields. Analysis of specific predictions of each model and crucial recent data on new mutants suggest that ciliary function may not be a broadly conserved, initiating event in left–right patterning. Many questions about embryonic left–right asymmetry remain open, offering fascinating avenues for further research in cell, developmental, and evolutionary biology. Developmental Dynamics 239:3131–3146, 2010. © 2010 Wiley‐Liss, Inc.
Inducible Cx40‐Cre expression in the cardiac conduction system and arterial endothelial cells
Authors: Beyer Sabrina , Kelly Robert G. , Miquerol Lucile
Published: October 2010

The Connexin‐40 (Cx40) gene encodes a gap junction protein that plays an important role in cell‐cell communication in cardiomyocytes of the atria and cardiac conduction system and endothelial cells of large arteries. During embryonic development, Cx40 expression is tightly regulated and correlates with progressive ventricular conduction system (VCS) differentiation and vessel function. We have generated Cx40Cre mice carrying a CreERT2‐IRESmRFP cassette by targeted recombination. In Cx40Cre mice, the pattern of expression of RFP is identical to that of the endogenous Cx40 gene and a Cx40GFP allele. Using a LacZ‐based Cre reporter mouse line, tamoxifen dependent Cre recombination was observed throughout the spatio‐temporal profile of Cx40 expression in the VCS and arterial endothelial cells. Cx40Cre mice can therefore be used to direct inducible genetic modification in Cx40 expressing cells. genesis 49:83–91, 2011. © 2010 Wiley‐Liss, Inc.
Tris‐Dioximate Cobalt(I,II,III) Clathrochelates: Stabilization of Different Oxidation and Spin States of an Encapsulated Metal Ion by Ribbed Functionalization
Authors: Voloshin Yan Z. , Varzatskii Oleg A. , Novikov Valentin V. , Strizhakova Nataly G. , Vorontsov Ivan I. , Vologzhanina Anna V. , Lyssenko Konstantin A. , Romanenko Galina V. , Fedin Matvey V. , Ovcharenko Victor I. , Bubnov Yurii N.
Published: October 2010

Boron‐capped hexachlorine‐containing cobalt(II) clathrochelates were prepared by means of template condensation of dichloroglyoxime (Cl2GmH2) with boron‐containing Lewis acids on a cobalt(II) ion matrix. The nucleophilic substitution of the reactive chlorine atoms of these macrobicyclic tris‐dioximates with thiolate anions gave the hexasulfide cobalt(II) and dodecasulfide CoIIICoIICoIII mono‐ and bis‐clathrochelates. The treatment of the hexachlorine‐containing cobalt(II) precursors with primary aliphatic amines afforded hexaamine cobalt(III) clathrochelates. The reduction of these precursors led to the clathrochelate [Co(Cl2Gm)3(BR)2]– anions, which were isolated as the salts with bulky organic cations. The relative stability of these cobalt(I) complexes accounted for a strong electronic effect of six electron‐withdrawing ribbed chlorine substituents. Superconducting quantum interference device (SQUID) magnetometry, EPR, and multitemperature X‐ray diffraction data showed that the cobalt(II) clathrochelates undergo gradual and incomplete ${1 \over 2}$ ↔ 3/2 spin transition. The Jahn–Teller distortion of the low‐spin encapsulated cobalt(II) ion causes its shift in the direction of one of the three chelate α‐dioximate fragments. The anisotropic displacement parameters were used to estimate the ordering of the molecular species, and the superposition of two Jahn–Teller distorted structures was found in a crystal. The cyclic voltammetry (CV) data showed the influence of the substituents in α‐dioximate fragments on the redox potentials of an encapsulated cobalt ion. The electron‐withdrawing ribbed substituents stabilize the cobalt(I) oxidation state of this ion because of electron‐density delocalization on their ribbed substituents, whereas the electron‐donating amine groups stabilize the cobalt(III) oxidation state.
Coordination Properties of Organoborate Ligands – Steric Hindrance Around the Distal Boron Center Directs the Conformation of the Dialkylbis(imidazolyl)borate Scaffold
Authors: Hikichi Shiro , Fujita Koyu , Manabe Yoshitaka , Akita Munetaka , Nakazawa Jun , Komatsuzaki Hidehito
Published: October 2010

Alkylmethylbis(imidazolyl)borate ligands, [B(ImN–Me)2(alkyl)Me]– (Lalkyl; alkyl = methyl and n‐butyl), have been synthesized by nucleophilic substitution from the chloride to the corresponding alkyl derivative on the boron center of the chloroborate precursor. In homoleptic complexes of nickel(II) with Lalkyl, [NiII(Lalkyl)2] (1alkyl), one of the two alkyl groups on the boron atom faces the nickel(II) center to form a C–H···M interaction. In the analogous homoleptic nikel(II) complexes of the hydride, phenyl, and methoxy derivatives 1X (X = H, Ph, OMe), the boron‐attached CH3 moieties do not turn towards the metal center. Steric repulsion between the methyl substituent on the imidazolyl ligands and the boron‐attached methyl group directs the orientation of the alkyl groups on Lalkyl. In the solution state the molecular structures of 1alkyl observed in the solid state are retained. Mixed‐ligand complexes, [NiII(Lalkyl)(TpiPr2)] (2alkyl), can be synthesized by reaction of [NiII(Y)(TpiPr2)] (Y = Cl, NO3) with Lalkyl through selective ligand metathesis. In 2Me, one methyl group of LMe approaches the nickel center retaining the bent conformation of the two imidazolyl groups. Conversely, the carbon atoms of the boron‐attached nBu and Me groups of LBu are located away from the nickel center, and the orientation of the two imidazolyl groups is almost coplanar in 2Bu. The structural characteristics of these nickel(II) complexes demonstrate the flexibility of the dialkybis(imidazolyl)borate scaffold.
Genetic diversity of fatty acids in sesame and its relatives in Nigeria
Authors: Azeez Musibau A. , Morakinyo Joseph A.
Published: October 2010

The genetic diversity in seed lipid and fatty acid composition in nine accessions of sesame, comprising six cultivated and three wild relatives, was studied and compared. Seed oil content was 53.23–55.12% in cultivated and 53.35–58.56% in wild accessions. The principal fatty acids in the accessions were palmitic, stearic, oleic (OLE), linoleic (LIN) and linolenic (LIL) acids, of which lower OLE and higher LIN acids were observed in all the accessions. Principal component analysis revealed that OLE acid, total unsaturated fatty acids, total saturated fatty acids (SFAs), LIN acid and the unsaturated to SFA ratio had the highest loading in the first component, which accounted for 54.01% of the total variation. For the second principal components, lauric, palmitoleic, capric, lignoceric, arachidic and LIL acids had the highest loading, accounting for 26.94% of the total variation. Three principal components explained 89.01% of the total variation. The dendrogram generated by the UPGMA cluster analysis grouped the nine accessions into five distinct clusters, indicating genetic diversity; this can be used to plan crosses and maximise the expression of heterosis.

Practical applications: This research work provides information on the fatty acid profile of seed oil from nine morphologically distinct accessions of sesame selected from thirty‐three accessions collected in 2003. This is intended to establish genetic diversity on the basis of fatty acid profile, identify accessions with high seed oil quality that may be adopted for large scale cultivation in Nigeria and justify the suitability of the nine accessions in serving as base materials in the ongoing breeding efforts for sesame seed oil quantity and quality improvement.
Cholesterol oxidation in lard as affected by CLA during heating – A kinetic approach
Authors: Yen Ting‐Yang , Lu Yi‐Fa , Inbaraj Baskaran Stephen , Chen Bing‐Huei
Published: October 2010

The objectives of this study were to determine the effect of two CLAs , 9‐cis, 11‐trans CLA and 10‐trans, 12‐cis on cholesterol degradation and cholesterol oxidation products (COPs) formation in lard during heating for varied length of time. No CLAs and approximately 1770.1 µg/mL of cholesterol were detected in lard. Additionally, there was no significant change in the level of cholesterol and COPs in lard during heating at 100°C over a period of 240 min. But, at 150 or 200°C, the degradation of cholesterol was prominent with substantial amount of COPs being formed. Formation profiles of 7‐OOH, 7‐OH, and 7‐keto at 150°C as well as 5,6‐epoxides at both 150 and 200°C were fitted by a first‐order equation, while a pseudo‐second‐order model described the kinetic pathway of 7‐OH and 7‐keto formation at 200°C. The formation of 7‐OOH at 200°C were fitted as multiple first‐order formation and first‐order degradation curves as its level reached a peak at 60 min and declined to zero. Incorporation of 100 µg/mL CLA showed antioxidant activity, whereas a prooxidant activity was observed for CLA at 500 µg/mL. The outcome of this study demonstrated the potential of CLA to be an antioxidant in oil system.
Synthesis and DNA Interaction of Platinum Complex/Peptide Chimera as Potential Drug Candidates (Eur. J. Org. Chem. 32/2010)
Authors: Damian Mariana S. , Hedman Hanna K. , Elmroth Sofi K. C. , Diederichsen Ulf
Published: October 2010

The cover picture shows the covalent DNA binding of cisplatin‐like complexes. These molecules were designed as hybrids between the platinum coordination site and positively charged peptides, which involves the covalent binding of one or two nucleobases by cisplatin‐analogous platinum complexes and the bending of double‐stranded DNA initiated by the peptide chain. An optimization of cisplatin‐like anticancer drugs is intended. Binding of cisplatin analogs is facilitated by simultaneous DNA bending. Details are discussed in the article by U. Diederichsen et al. on p. 6161 ff.
Bootstrap estimation of confidence intervals on mutation rate ratios
Authors: Russell Matthew S. , March John C.
Published: October 2010

The fluctuation test is a useful tool for estimating the mutation rate of cells. However, statistical methods for comparing mutation rate estimates between different strains or conditions have not yet been fully developed. Methods exist for placing confidence intervals on estimates of the number of mutational events in cultures for a given strain and set of conditions, but placing confidence intervals on mutation rate is complicated by differences in the final number of cells in culture between parallel cultures. Additionally, confidence intervals on individual mutation rate estimates are not always the most useful statistical tool when comparing two or more different strains or conditions. We present a bootstrap method for estimating confidence intervals on the quotient of two mutation rates determined from two fluctuation test experiments using experimental and control strains or conditions. We use Monte Carlo simulations to validate this method over a wide range of mutation rates and for empirically measured variation in the estimates of final number of cells in culture. Furthermore, we provide the computational tools to implement the bootstrap method described here on experimental fluctuation test data and to evaluate this method for experimental parameters other than those considered herein. Environ. Mol. Mutagen., 2011. © 2010 Wiley‐Liss, Inc.
Grey matter deficit in long‐term recovered anorexia nervosa patients
Authors: Joos Andreas , Hartmann Armin , Glauche Volkmar , Perlov Evgeniy , Unterbrink Thomas , Saum Barbara , Tüscher Oliver , Tebartz van Elst Ludger , Zeeck Almut
Published: October 2010

Objective

Cerebral grey matter (GM) reduction has repeatedly been shown in anorexia nervosa (AN). Evidence concerning completeness of GM restitution in recovered patients is contradictory.

Methods

Five long‐term recovered patients with AN were compared to symptomatic subjects and healthy controls using voxel‐based morphometry. Whole brain GM, white matter and cerebrospinal fluid fractions were studied. Additionally, voxels that had shown significant GM reductions in symptomatic patients were investigated.

Results

Recovered subjects had been severely affected when symptomatic (mean body mass index: 12.1 kg/m2) and were in remission for a very long time period (>5 years). Whole brain tissue fractions did not differ from controls. Regional analysis showed persistent GM volume reduction, in particular of the precuneus.

Conclusions

This study further supports the assumption that GM volume restitution is incomplete in subjects, who had previously been severely affected by anorexia nervosa. The meaning of GM reduction in long‐term recovered AN patients, that is, its pathophysiological relevance, however, remains unclear. Furthermore, the precise aetiology of GM reduction remains an open question. Copyright © 2010 John Wiley & Sons, Ltd and Eating Disorders Association.
Competitive stress can make the herbicide Roundup® more deadly to larval amphibians
Authors: Jones Devin K , Hammond John I , Relyea Rick A
Published: October 2010

Toxicity assessments on nontarget organisms have largely been addressed using short-term, single-species laboratory experiments. Although extremely helpful, these experiments inherently lack many pervasive ecological stressors found in nature. Though a substantial challenge, incorporating these ecological stressors in contaminant studies would shed light on potential synergistic effects. For the world's leading herbicide, glyphosate, we know little about how natural stressors affect the toxicity to nontarget organisms. To explore how the natural stress of competition might interact with a glyphosate-based herbicide, we used outdoor mesocosms containing three tadpole species that were exposed to a factorial combination of three glyphosate concentrations (0, 1, 2, or 3 mg acid equivalent (a.e.)/L of the commercial formulation Roundup Original MAX®) and three tadpole densities (low, medium, or high). We found that increased tadpole density caused declines in tadpole growth, but also made the herbicide significantly more lethal to one species. Whereas the median lethal concentration (LC50) values were similar across all densities for gray treefrogs (Hyla versicolor; 1.7–2.3 mg a.e./L) and green frogs (Rana clamitans; 2.2–2.6 mg a.e./L), the LC50 values for bullfrogs (R. catesbeiana) were 2.1 to 2.2 mg a.e./L at low and medium densities, but declined to 1.6 mg a.e./L at high densities. The large decrease in amphibian survival with increased herbicide concentration was associated with increases in periphyton abundance. We also found evidence that temperature stratification lead to herbicide stratification in the water column, confirming the results of a previous study and raising important questions about exposure risk in natural systems. Environ. Toxicol. Chem. 2011;30:446–454. © 2010 SETAC
Endocrine potency of wastewater: Contents of endocrine disrupting chemicals and effects measured by in vivo and in vitro assays
Authors: Kusk Kresten Ole , Krüger Tanja , Long Manhai , Taxvig Camilla , Lykkesfeldt Anne E , Frederiksen Hanne , Andersson Anna-Maria , Andersen Henrik R , Hansen Kamilla M. S , Nellemann Christine , Bonefeld-Jørgensen Eva C
Published: October 2010

Industrial and municipal effluents are important sources of endocrine disrupting compounds (EDCs) discharged into the aquatic environment. This study investigated the endocrine potency of wastewater and the cleaning efficiency of two typical urban Danish sewage treatment plants (STPs), using chemical analysis and a battery of bioassays. Influent samples, collected at the first STP grate, and effluent samples, collected after the sewage treatment, were extracted using solid phase extraction. Extracts were analyzed for the content of a range of industrial chemicals with endocrine disrupting properties: phthalate metabolites, parabens, industrial phenols, ultraviolet screens, and natural and synthetic steroid estrogens. The endocrine disrupting bioactivity and toxicity of the extracts were analyzed in cell culture assay for the potency to affect the function of the estrogen, androgen, aryl hydrocarbon, and thyroid receptors as well as the steroid hormone synthesis. The early-life stage (ELS) development was tested in a marine copepod. The concentrations of all analyzed chemicals were reduced in effluents compared with influents, and for some to below the detection limit. Influent as well as effluent samples from both STPs were found to interact with all four receptors and to interfere with the steroid hormone synthesis showing the presence of measured EDCs. Both influent samples and one of the effluent samples inhibited the development of the copepod Acartia tonsa. In conclusion, the presence of EDCs was reduced in the STPs but not eliminated, as verified by the applied bioassays that all responded to the extracts of effluent samples. Our data suggest that the wastewater treatment processes are not efficient enough to prevent contamination of environmental surface waters. Environ. Toxicol. Chem. 2011;30:413–426. © 2010 SETAC
Environmental contaminant effects on juvenile striped bass in the San Francisco Estuary, California, USA
Authors: Spearow Jimmy L , Kota Rama S , Ostrach David J
Published: October 2010

The decline of pelagic organisms in the San Francisco Estuary (SFE) (California, USA) is attributed to several factors, including water diversions, invasive species, and exposure to environmental toxicants. The present study evaluated the effects of environmental contaminants on liver vitellogenin, metallothionein, 7-ethoxyresorufin-O-deethylase (EROD), and benzyloxyresorufin O-deethylase (BROD) activity in juvenile striped bass (Morone saxitilis) in the SFE. Analysis of juvenile striped bass liver extracts revealed site-specific elevations of vitellogenin, metallothionein, and EROD biomarkers across the estuary. Although some striped bass in the estuary showed EROD activity similar to unhandled hatchery controls, several sites in the estuary showed significantly higher EROD activity that was in the range of beta-naphthoflavone (BNF)–injected, positive controls. Overall, EROD activity averaged 283% higher in estuary fish than in hatchery controls. Chemical analyses of extracts from semipermeable membrane devices (SPMDs) deployed in the estuary for one month showed elevated polyaromatic hydrocarbon (PAH) levels. Semipermeable membrane devices extract injections-induced metallothionein and BROD in striped bass livers. These data show that environmental exposures are impacting EROD and other biomarkers in the SFE striped bass population. Previous studies in our laboratory have associated poor larval development with maternal transfer of environmental contaminants. Further studies are needed to monitor contaminant exposures by the use of biomarkers and to integrate them into a more effective pelagic species recovery plan in the SFE. Environ. Toxicol. Chem. 2011;30:393–402. © 2010 SETAC
Phytochelatin induction by selenate in Chlorella vulgaris, and regulation of effect by sulfate levels
Authors: Simmons Denina B. D , Emery R. J. Neil
Published: October 2010

Phytochelatins (PCs) are short metal detoxification peptides made from the sulfur-rich molecule glutathione. The production of PCs by algae caused by Se exposure has never been studied, although many algae accumulate Se, forming Se-rich proteins and peptides, and higher plants have demonstrated PC production when treated with Se; therefore, a goal of the current study was to examine whether Se induces PC production in algae. Furthermore, selenate is thought to compete with sulfate in the S assimilation pathway, and sulfate therefore may have a protective effect against the toxic effects of high doses of Se in algae. Hence, the interaction of selenate and sulfate was investigated with respect to the induction of PCs. Chlorella vulgaris was cultured in media with either low (31.2 µM) or high (312 µM) concentrations of sulfate. These cultures were exposed to selenate in doses of 7, 35, and 70 nM for 48 h. In a separate treatment, Cd (890 nM) was added as a positive PC-inducing control, and one no-metal negative control was used. Total Se and Se speciation were determined, and glutathione, phytochelatin-2, and phytochelatin-3 were quantified in each of cell digests, cell medium, and cell lysates. We found that PCs and their precursor glutathione were induced by selenate as well as by a Cd control. The high concentration of sulfate was able to counter selenate-induced production of PCs and glutathione. These data support two possible mechanisms: a negative feedback system in the S assimilation pathway that affects PC production when sulfate is abundant, and competition for uptake at the ion transport level between selenate and sulfate. Environ. Toxicol. Chem. 2011;30:469–476. © 2010 SETAC
Comparing effects of low levels of herbicides on greenhouse- and field-grown potatoes (Solanum tuberosum L.), soybeans (Glycine max L.), and peas (Pisum sativum L.)
Authors: Pfleeger Thomas , Olszyk David , Lee E. Henry , Plocher Milton
Published: October 2010

Although laboratory toxicology tests are generally easy to perform, cost effective, and readily interpreted, they have been questioned for their environmental relevance. In contrast, field tests are considered realistic while producing results that are difficult to interpret and expensive to obtain. Toxicology tests were conducted on potatoes, peas, and soybeans grown in a native soil in pots in the greenhouse and were compared to plants grown outside under natural environmental conditions to determine toxicological differences between environments, whether different plant developmental stages were more sensitive to herbicides, and whether these species were good candidates for plant reproductive tests. The reproductive and vegetative endpoints of the greenhouse plants and field-grown plants were also compared. The herbicides bromoxynil, glyphosate, MCPA ([4-chloro-2-methylphenoxy] acetic acid), and sulfometuron-methyl were applied at below field application rates to potato plants at two developmental stages. Peas and soybeans were exposed to sulfometuron-methyl at similar rates at three developmental stages. The effective herbicide concentrations producing a 25% reduction in a given measure differed between experimental conditions but were generally within a single order of magnitude within a species, even though there were differences in plant morphology. This study demonstrated that potatoes, peas, and soybeans grown in pots in a greenhouse produce phytotoxicity results similar to those grown outside in pots; that reproductive endpoints in many cases were more sensitive than vegetative ones; and that potato and pea plants are reasonable candidates for asexual and sexual reproductive phytotoxicity tests, respectively. Plants grown in pots in a greenhouse and outside varied little in toxicity. However, extrapolating those toxicity results to native plant communities in the field is basically unknown and in need of research. Environ. Toxicol. Chem. 2011;30:455–468. © 2010 SETAC
Application of ambient analysis techniques for the estimation of electromechanical oscillations from measured PMU data in four different power systems
Authors: Vanfretti Luigi , Dosiek Luke , Pierre John W. , Trudnowski Daniel , Chow Joe H. , García‐Valle Rodrigo , Aliyu Usman
Published: October 2010

The application of advanced signal processing techniques to power system measurement data for the estimation of dynamic properties has been a research subject for over two decades. Several techniques have been applied to transient (orringdown) data, ambient data, and to probing data. Some of these methodologies have been included in off‐line analysis software, and are now being incorporated into software tools used in control rooms for monitoring the near real‐time behavior of power system dynamics. In this paper we illustrate the practical application of some ambient analysis methods for electromechanical mode estimation in different power systems. We apply these techniques to phasor measurement unit (PMU) data from stored archives of several hours originating from the US Eastern Interconnection (EI), the Western Electricity Coordinating Council (WECC), the Nordic Power System, and time‐synchronized Frequency Disturbance Recorder (FDR) data from Nigeria. It is shown that available signal processing tools are readily applicable for analysis of different power systems, regardless of their specific dynamic characteristics. The discussions and results in this paper are of value to power system operators and planners as they provide information of the applicability of these techniquesviareadily available signal processing tools, and in addition, it is shown how to critically analyze the results obtained with these methods. Copyright © 2010 John Wiley & Sons, Ltd.
Using adjoint error estimation techniques for elastohydrodynamic lubrication line contact problems
Authors: Hart D. E. , Berzins M. , Goodyer C. E. , Jimack P. K.
Published: October 2010

The use of an adjoint technique for goal‐based error estimation described by Hartit et al. (Int. J. Numer. Meth. Fluids 2005; 47:1069–1074) is extended to the numerical solution of free boundary problems that arise in elastohydrodynamic lubrication (EHL). EHL systems are highly nonlinear and consist of a thin‐film approximation of the flow of a non‐Newtonian lubricant which separates two bodies that are forced together by an applied load, coupled with a linear elastic model for the deformation of the bodies. A finite difference discretization of the line contact flow problem is presented, along with the numerical evaluation of an exact solution for the elastic deformation, and a moving grid representation of the free boundary that models cavitation at the outflow in this one‐dimensional case. The application of a goal‐based error estimate for this problem is then described. This estimate relies on the solution of an adjoint problem; its effectiveness is demonstrated for the physically important goal of the total friction through the contact. Finally, the application of this error estimate to drive local mesh refinement is demonstrated. Copyright © 2010 John Wiley & Sons, Ltd.
Numerical simulation of compressible turbulent flow via improved gas‐kinetic BGK scheme
Authors: Xiong Shengwei , Zhong Chengwen , Zhuo Congshan , Li Kai , Chen Xiaopeng , Cao Jun
Published: October 2010

In order to solve compressible turbulent flow problems, this study focuses on incorporating the Spalart–Allmaras turbulence model into gas‐kinetic BGK (Bhatnagar–Gross–Krook) scheme. The Spalart–Allmaras turbulence model is solved using finite difference discretization. The variables on the cell interface are interpolated via the van Leer limiter in the reconstruction stage. Simulation of subsonic and transonic flow over a NACA0012 airfoil has been implemented using two‐dimensional body‐fitted grids. The numerical results obtained appear in good agreement with the AGARD results, demonstrating the effectiveness and usefulness of the strategy of coupling the Spalart–Allmaras turbulence model with the BGK scheme for compressible turbulent flow simulation. Copyright © 2010 John Wiley & Sons, Ltd.
A multidimensional HLL‐Riemann solver for non‐linear hyperbolic systems
Authors: Capdeville G.
Published: October 2010

This article presents a numerical model that enables to solve on unstructured triangular meshes and with a high order of accuracy, Riemann problems that appear when solving hyperbolic systems.

For this purpose, we use a MUSCL‐like procedure in a ‘cell‐vertex’ finite‐volume framework.

In the first part of this procedure, we devise a four‐state bi‐dimensional HLL solver (HLL‐2D). This solver is based upon the Riemann problem generated at the barycenter of a triangular cell, from the surrounding cell‐averages. A new three‐wave model makes it possible to solve this problem, approximately. A first‐order version of the bi‐dimensional Riemann solver is then generated for discretizing the full compressible Euler equations.

In the second part of the MUSCL procedure, we develop a polynomial reconstruction that uses all the surrounding numerical data of a given point, to give at best third‐order accuracy. The resulting over determined system is solved by using a least‐square methodology. To enforce monotonicity conditions into the polynomial interpolation, we use and adapt the monotonicity‐preserving limiter, initially devised by Barth (AIAA Paper 90‐0013, 1990).

Numerical tests and comparisons with competing numerical methods enable to identify the salient features of the whole model. Copyright © 2010 John Wiley & Sons, Ltd.
A heterogeneous multiscale modeling framework for hierarchical systems of partial differential equations
Authors: Masud Arif , Scovazzi Guglielmo
Published: October 2010

This paper presents a heterogeneous multiscale method with efficient interscale coupling for scale‐dependent phenomena modeled via a hierarchy of partial differential equations. Physics at the global level is governed by one set of partial differential equations, whereas features in the solution that are beyond the resolution capability of the coarser models are accounted for by the next refined set of differential equations. The proposed method seamlessly integrates different sets of equations governing physics at various levels, and represents a consistent top–down and bottom–up approach to multi‐model modeling problems. For the top–down coupling of equations, this method provides a variational residual‐based embedding of the response from the coarser or global system equations, into the corresponding local or refined system equations. To account for the effects of local phenomena on the global response of the system, the method also accommodates bottom–up embedding of the response from the local or refined mathematical models into the global or coarser model equations. The resulting framework thus provides a consistent way of coupling physics between disparate partial differential equations by means of up‐scaling and down‐scaling of the mathematical models. An integral aspect of the proposed framework is an uncertainty quantification and error estimation module. The structure of this error estimator is investigated and its mathematical implications are delineated. Copyright © 2010 John Wiley & Sons, Ltd.
Computer‐algebra multiple‐timescale method for spatially periodic thin‐film viscous‐flow problems
Authors: Groh Christian M. , Kelmanson Mark A.
Published: October 2010

A flexible, fully automated, computer‐algebra algorithm is developed for solving a class of non‐linear partial‐differential evolution equations arising frequently in the modeling of two‐dimensional transient free‐surface viscous thin‐film flows. The method, which is formulated for solving spatially periodic problems, is based upon an explicit multiple‐timescale asymptotic approximation of the thin‐film thickness. It admits the resolution of diverse physical phenomena by employing a finite geometric progression of increasingly slow timescales.

The method is implemented on a challenging test problem comprising the evolution of an annular film of viscous liquid, with a free surface, adhering to the exterior of a horizontal rotating circular cylinder; as a model for numerous industrially motivated coating flows, this benchmark problem has been analyzed in diverse numerical and theoretical studies, against whose results those of the present method are compared.

The explicit algebraic form of the solution admits a study of large‐time evolutionary dynamics that lies beyond the reach of considerably more expensive conventional numerical solvers, thereby shedding new light on the hitherto‐undiscovered explicit dependence of large‐time evolutionary fluid dynamics in terms of independent parameters describing gravitational and capillary effects.

The results obtained from the new computer‐algebra procedure are demonstrated to be in good agreement with those obtained from a bespoke efficient numerical integration method that is spectrally accurate in space and 8th‐order (Runge–Kutta) in time. Newly discovered mechanisms describing the decay of free‐surface wave modes, from arbitrary initial conditions to the steady state, are presented. Copyright © 2010 John Wiley & Sons, Ltd.
An implicit full Eulerian method for the fluid–structure interaction problem
Authors: Ii S. , Sugiyama K. , Takeuchi S. , Takagi S. , Matsumoto Y.
Published: October 2010

A numerical method, which relaxes limitation of small time increment in fluid–structure interaction (FSI) simulations with hard solid, is developed based on a full Eulerian FSI model (Sugiyama et al. Comput. Mech. 2010; 46(1):147–157). In this model, the solid volume fraction is applied for describing the multicomponent material, and the left Cauchy‐Green deformation tensor is introduced to describe the deformation of the hyperelastic body. The transport equations for them are solved by finite difference formulation on a fixed Cartesian coordinate grid. In this paper, a simple implicit formulation is proposed for the elastic stress to avoid restriction and instability due to high stiffness. Both linear and nonlinear hyperelastic materials are treated by a unified formulation by introducing a fourth‐order Jacobian tensor to overcome the difficulty associated with the difference between the constitutive laws of solid and fluid. The numerical examples are carried out in two dimensions, and the proposed method is confirmed to work well for hard Mooney–Rivlin materials. It is also applied to 2D wall‐bounded flows involving biconcave particles, and the effects of the solid stiffness on the shape and distribution of the particles, and the overall flow rate are discussed. Copyright © 2010 John Wiley & Sons, Ltd.
On the discontinuous Galerkin computation of N‐waves focusing
Authors: Sescu Adrian , Afjeh Abdollah A.
Published: October 2010

Sonic boom focusing phenomenon can be predicted using the solution to the nonlinear Tricomi equation which is a hybrid (hyperbolic‐elliptic) second‐order partial differential equation. In this paper, the hyperbolic conservation law form is derived, which is valid in the entire domain. In this manner, the presence of two regions where the equation behaves differently (hyperbolic in the upper and elliptic in the lower half‐plane) is avoided. On the upper boundary, a new mixed boundary condition for the acoustic pressure is employed. The discretization is carried out using a discontinuous Galerkin (DG) method combined with a Runge–Kutta total‐variation diminishing scheme. The results show the accuracy of DG methods to solve problems involving sharp gradients and discontinuities. Comparisons with analytical results for the linear case, and other numerical results using classical explicit and compact finite difference schemes and weighted essentially non‐oscillatory schemes are included. Copyright © 2010 John Wiley & Sons, Ltd.
Joint testing of genotype and ancestry association in admixed families
Authors: Tang Hua , Siegmund David O. , Johnson Nicholas A. , Romieu Isabelle , London Stephanie J.
Published: October 2010

Current genome‐wide association studies (GWAS) often involve populations that have experienced recent genetic admixture. Genotype data generated from these studies can be used to test for association directly, as in a non‐admixed population. As an alternative, these data can be used to infer chromosomal ancestry, and thus allow for admixture mapping. We quantify the contribution of allele‐based and ancestry‐based association testing under a family‐design, and demonstrate that the two tests can provide non‐redundant information. We propose a joint testing procedure, which efficiently integrates the two sources information. The efficiencies of the allele, ancestry and combined tests are compared in the context of a GWAS. We discuss the impact of population history and provide guidelines for future design and analysis of GWAS in admixed populations. Genet. Epidemiol. 34:783‐791, 2010. © 2010 Wiley‐Liss, Inc.
The economic impact of dementia in Europe in 2008—cost estimates from the Eurocode project
Authors: Wimo A. , Jönsson L , Gustavsson A. , McDaid D. , Ersek K. , Georges J. , Gulácsi L. , Karpati K. , Kenigsberg P. , Valtonen H.
Published: October 2010

Objective

Care for demented people is very resource demanding, the prevalence is increasing and there is so far no cure.

Cost of illness (CoI) studies are important by identifying the distribution of costs between different payers of care. The European Union (EU) funded the European Collaboration on Dementia (Eurocode) as part of the EU's 2005 work plan of the Community public health programme. Eurocode was administered by Alzheimer Europe.

The aim was to describe the economic impact of dementia in Europe in 2008.

Methods

Eurocode's new estimates for dementia prevalence were included in a cost model based on published European CoI papers. For countries where no CoI figures were available, imputation was used.

Results

The total CoI of dementia in the EU27 in 2008 was estimated to be €160 billion (€22 000 per demented per year), of which 56% were costs of informal care. The corresponding costs for the whole Europe was €177 billion. In northern Europe, the direct costs are estimated to be considerabe, while the cost of informal care is the major cost component in southern Europe. The sensitivity analysis showed a range for total EU27 costs between €111 and 168 billion.

Conclusions

The estimated CoI in this study is higher than in previous studies. There are also large differences in different European regions. Notwithstanding the methodological challenges, the societal costs of dementia in Europe are very high which in turn have substantial resource impacts on the social and health care systems in Europe. Copyright © 2010 John Wiley & Sons, Ltd.
Lack of awareness of symptoms in people with dementia: the structural and functional basis
Authors: Zamboni G. , Wilcock G.
Published: October 2010

Objective

To review studies investigating the brain correlates of unawareness of cognitive and behavioural symptoms in people with dementia.

Design

A detailed search of the literature was conducted to include all the peer‐reviewed studies published in English aimed at identifying the structural or functional brain correspondents of unawareness in dementia patients. Their results were interpreted in relation to the methodological differences in terms of type of dementia studied, the protocol adopted to measure lack of awareness, the imaging techniques employed, the experimental designs and statistical analyses performed.

Results

Eighteen studies undertaken to explore the functional and structural correlates of unawareness of cognitive symptoms in dementia were identified. Although their results showed a disparate range of brain correlates, they were mainly localized in frontal and temporo‐parietal regions.

Conclusions

Although the anatomical correlates of unawareness of disease in dementia have not yet been exhaustively explored, understanding the correlates of unawareness may also contribute to understand the brain correlates of self‐awareness and self‐reflection. We discuss the current knowledge base and consider potential future directions for research. Copyright © 2010 John Wiley & Sons, Ltd.
Synergistic associations of depression and apolipoprotein E genotype with incidence of dementia
Authors: Kim Jae‐Min , Stewart Robert , Kim Seon‐Young , Kim Sung‐Wan , Bae Kyung‐Yeol , Yang Su‐Jin , Shin Il‐Seon , Yoon Jin‐Sang
Published: October 2010

Objectives

A cohort study of Japanese‐American men suggested interactive effects of depression and apolipoprotein E (APOE) e4 allele on risk of incident dementia. In another sample of East Asian origin, we sought to replicate the findings and to explore individual depressive symptoms where this interaction was most evident.

Methods

Of 625 Korean community elders without dementia at baseline, 518 (83%) were followed over a 2.4‐year period and were clinically assessed for incident dementia. Depression was identified by the Geriatric Mental State Schedule (GMS), and nine individual depressive symptoms relevant to DSM‐IV major depressive episode criteria were extracted. APOE genotype was ascertained. Covariates included age, gender, education, and disability.

Results

There were synergistic interactions between depression and APOE e4 on incident dementia independent of covariates. This interaction was particularly strong for four depressive symptoms: depressed mood, worthlessness, concentration difficulty, and suicidal ideation.

Conclusions

We were able to replicate the previous study, finding that, at least in East Asian origin populations, the APOE e4 allele is a stronger predictor of incident dementia in the presence of depressive syndrome, and particular depressive symptoms. Copyright © 2010 John Wiley & Sons, Ltd.