bluuebunny/crossref_metadata_2025 huggingface dataset:
Review of in situ remediation technologies for lead, zinc, and cadmium in soil
Authors: Martin Todd A. , Ruby Michael V.
Published: June 2004

This article presents a review of in situ technologies for the remediation of soils contaminated with lead, zinc, and/or cadmium. The objective of this review is to assess the developmental status of the available in situ technologies and provide a general summary of typical applications and limitations of these technologies. The literature review identified seven in situ remediation technologies—solidification/stabilization, vitrification, electrokinetic remediation, soil flushing, phytoextraction, phytostabilization, and chemical stabilization. These technologies were considered for their ability to meet a specific set of remediation objectives under a range of conditions. Each of these technologies has both strengths and weaknesses for addressing particular remedial situations discussed in the article for each of the technologies. A general summary of which technologies are most applicable to common remedial scenarios is also provided. © 2004 Wiley Periodicals, Inc.
Superfund site remediation by landfilling—overview of landfill design, operation, closure, and postclosure issues
Authors: Lee G. Fred , Jones‐Lee Anne
Published: June 2004

This article discusses the appropriateness of using landfills as part of remediating hazardous chemical and Superfund sites, with particular emphasis on providing for true long‐term public health and environmental protection from the wastes and contaminated soils that are placed in the landfills. On‐site landfilling or capping of existing wastes is typically the least expensive approach for gaining some remediation of existing hazardous chemical/Superfund sites. The issues of the deficiencies in US EPA and state landfilling approaches discussed herein are also applicable to the landfilling of municipal and industrial solid “nonhazardous” wastes. These deficiencies were presented in part as “Problems with Landfills for Superfund Site Remediation” at the US EPA National Superfund Technical Assistance Grant Workshop held in Albuquerque, New Mexico, in February 2003. They are based on the author's experience in investigating the properties of landfill liners and the characteristics of today's landfills, relative to their ability to prevent groundwater pollution and to cause other environmental impacts. Discussed are issues related to both solid and hazardous waste landfills and approaches for improving the ability of landfills to contain wastes and monitor for leachate escape from the landfill for as long as the wastes in the landfill will be a threat. © 2004 Wiley Periodicals, Inc.
Assessing the potential of using phytoremediation for pyrene‐contaminated soils
Authors: Chekol Tesema , Vough Lester R.
Published: June 2004

Forage crop species representing two biologically distinct families (legumes and grasses) were evaluated on soil spiked with 100 mg/kg of pyrene to determine the potential effectiveness of the rhizospheres of these plants for phytoremediation. In this experiment, pyrene dissipation could not be attributed to the presence of plants. Pyrene dissipation was also not related to rhizosphere biological activity, such as microbial counts and enzyme activity. Planting with reed canarygrass and switchgrass significantly increased the microbial counts in soil; however, the differences in the microbial counts were not correlated to the levels of pyrene dissipation. Reed canarygrass rhizosphere had significantly higher dehydrogenase activity compared to the switchgrass rhizosphere, but this difference in soil dehydrogenase activity was not related to pyrene dissipation. In general, the use of plants was not effective in causing pyrene transformation; however, the presence of vegetation on polycyclic aromatic hydrocarbon–contaminated soils could play a significant role in limiting the spread of contaminants (erosion, leaching) and enhancing ecosystem restoration. © 2004 Wiley Periodicals, Inc.
On wind turbine power performance measurements at inclined airflow
Authors: Pedersen T. F.
Published: June 2004

The average airflow inclination in complex terrain may be substantial. The airflow inclination affects wind turbine performance and also affects the cup anemometer being used in power performance measurements. In this article the overall dependence of the power curve on inclined airflow is analysed for its influence on both the wind turbine and the cup anemometer. The wind turbine performance analysis is based on results of measurements and theoretical calculations with the aeroelastic code HAWC coupled to a 3D actuator disc model for varying yaw angle. The cup anemometer analysis at inclined flow is based on an averaging of measured angular characteristics in a wind tunnel with the distribution of airflow inclination angles over time. The relative difference in annual energy production in terrain with inclined airflow compared with flat terrain is simulated for cup anemometers with theoretical optimal angular characteristics for two different definitions of wind speed, as well as for five commercial cup anemometers with measured angular characteristics. Copyright © 2004 John Wiley & Sons, Ltd.
Suppressive effects of the kahweol and cafestol on cyclooxygenase‐2 expression in macrophages
Authors: Kim Ji Young , Jung Kyung Sik , Jeong Hye Gwang
Published: June 2004

Inducible cyclooxygenase‐2 (COX‐2) has been suggested to play a role in the processes of inflammation and carcinogenesis. Recent studies have shown the chemoprotective effects of kahweol and cafestol, which are coffee‐specific diterpenes. This study investigated the effects of kahweol and cafestol on the expression of COX‐2 in lipopolysaccharide (LPS)‐activated RAW 264.7 macrophages. Kahweol and cafestol significantly suppressed the LPS‐induced production of prostaglandin E2, COX‐2 protein and mRNA expression, and COX‐2 promoter activity in a dose‐dependent manner. Furthermore, kahweol blocked the LPS‐induced activation of NF‐κB by preventing IκB degradation and inhibiting IκB kinase activity. These results will provide new insights into the anti‐inflammatory and anti‐carcinogenic properties of kahweol and cafestol.
Differential regulation of the insulin‐like growth factor II mRNA‐binding protein genes by architectural transcription factor HMGA2
Authors: Brants Jan R , Ayoubi Torik A.Y , Chada Kiran , Marchal Kathleen , Van de Ven Wim J.M , Petit Marleen M.R
Published: June 2004

The developmentally regulated architectural transcription factor, high mobility group A2 (HMGA2), is involved in growth regulation and plays an important role in embryogenesis and tumorigenesis. Little is known, however, about its downstream targets. We performed a search for genes of which expression is strongly altered during embryonic development in two HMGA2‐deficient mouse strains, which display a pygmy‐phenotype, as compared to wild‐type mice. We found that the insulin‐like growth factor II mRNA‐binding protein 2 gene (IMP2), but not its family members IMP1 and IMP3, was robustly downregulated in mutant E12.5 embryos. Furthermore, we show that wild‐type HMGA2 and its tumor‐specific truncated form have opposite effects on IMP2 expression. Our results clearly indicate that HMGA2 differentially regulates expression of IMP family members during embryogenesis.
Thyroid status co‐regulates thyroid hormone receptor and co‐modulator genes specifically in the hypothalamus
Authors: Clerget-Froidevaux M.S , Seugnet I , Demeneix B.A
Published: June 2004

Regulation of Thyrotropin Releasing Hormone (TRH) transcription in the hypothalamus represents the central control point of thyroid function. To examine the expression of potential TRH regulatory components, we simultaneously amplified, by semi‐quantitative multiplex PCR system, nine key genes from ⩽100 ng total RNA from two brain areas (hypothalamus and cortex) under different thyroid states. Expression of TRβ
1 and TRβ
2 isoforms, key elements in TRH regulation, was modified by thyroid status in the hypothalamus but not in the cortex. Similarly, hypothyroidism increased specifically hypothalamic levels of three co‐modulator genes. This study provides the first demonstration of tissue specific co‐regulation of a set of genes by thyroid status within a defined brain area.
Calcitonin‐derived carrier peptide plays a major role in the membrane localization of a peptide–cargo complex
Authors: Boichot Sylvie , Krauss Ulrike , Plénat Thomas , Rennert Robert , Milhiet Pierre-Emmanuel , Beck-Sickinger Annette , Le Grimellec Christian
Published: June 2004

Bilayers made of dioleoylphosphatidylcholine (DOPC)/dipalmitoylphosphatidylcholine (DPPC) mixture containing or not cholesterol (Chl) were used to investigate the interaction of a carrier peptide with membranes. Atomic force microscopy revealed that the C‐terminal 9‐32 fragment of human calcitonin (hCT (9‐32)), free or coupled to enhanced green fluorescent protein (hCT‐eGFP) cargo forms aggregates in the DOPC fluid phase in absence of Chl and in the DPPC enriched liquid‐ordered phase when Chl is present. The data show that hCT (9‐32) plays a determinant role in the membrane localization of the peptide–cargo complex. They suggest that carpet‐like mechanism for membrane destabilization may be involved in the carrier function of hCT (9‐32).
Possible involvement of AMP‐activated protein kinase in obesity resistance induced by respiratory uncoupling in white fat
Authors: Matejkova Olga , Mustard Kirsty J , Sponarova Jana , Flachs Pavel , Rossmeisl Martin , Miksik Ivan , Thomason-Hughes Michaela , Grahame Hardie D , Kopecky Jan
Published: June 2004

The AMP‐activated protein kinase (AMPK) cascade is a sensor of cellular energy charge that promotes catabolic and inhibits anabolic pathways. However, the role of AMPK in adipocytes is poorly understood. We show that transgenic expression of mitochondrial uncoupling protein 1 in white fat, which induces obesity resistance in mice, is associated with depression of cellular energy charge, activation of AMPK, downregulation of adipogenic genes, and increase in lipid oxidation. Activation of AMPK may explain the complex metabolic changes in adipose tissue of these animals and our results support a role for adipocyte AMPK in the regulation of storage of body fat.
Identification and characterization of a UDP‐d‐glucuronate 4‐epimerase in Arabidopsis
Authors: Usadel Björn , Schlüter Urte , Mølhøj Michael , Gipmans Martijn , Verma Rajeev , Kossmann Jens , Reiter Wolf-Dieter , Pauly Markus
Published: June 2004

One of the major sugars present in the plant cell wall is d‐galacturonate, the dominant monosaccharide in pectic polysaccharides. Previous work indicated that one of the activated precursors necessary for the synthesis of pectins is UDP‐d‐galacturonate, which is synthesized from UDP‐d‐glucuronate by a UDP‐d‐glucuronate 4‐epimerase (GAE). Here, we report the identification, cloning and characterization of a GAE6 from Arabidopsis thaliana. Functional analysis revealed that this enzyme converts UDP‐d‐glucuronate to UDP‐d‐galacturonate in vitro. An expression analysis of this epimerase and its five homologs in the Arabidopsis genome by quantitative RT‐PCR and promoter::GUS fusions indicated differential expression of the family members in plant tissues and expression of all isoforms in the developing pollen of A. thaliana.
PSPN/GFRα4 has a significantly weaker capacity than GDNF/GFRα1 to recruit RET to rafts, but promotes neuronal survival and neurite outgrowth
Authors: Yang Jianmin , Lindahl Maria , Lindholm Päivi , Virtanen Heidi , Coffey Eleanor , Runeberg-Roos Pia , Saarma Mart
Published: June 2004

Previously, it was shown that the recruitment of RET into lipid rafts by glial cell line‐derived neurotrophic factor (GDNF)/GFRα1 is crucial for efficient signal transduction. Here, we show that the mouse GFRα4 is a functional, N‐glycosylated, glycosylphosphatidylinositol (GPI)‐anchored protein, which mediates persephin (PSPN)‐induced phosphorylation of RET, but has an almost undetectable capacity to recruit RET into the 0.1% Triton X‐100 insoluble membrane fraction. In spite of this, PSPN/mGFRα4 promotes neurite outgrowth in PC6‐3 cells and survival of cerebellar granule neurons. As we show that also human PSPN/GFRα4 is unable to recruit RET into lipid rafts, we propose that the mammalian GFRα4 in this respect differs from GFRα1.
Periplasmic competition for zinc uptake between the metallochaperone ZnuA and Cu,Zn superoxide dismutase
Authors: Berducci Giovanni , Mazzetti Anna Paola , Rotilio Giuseppe , Battistoni Andrea
Published: June 2004

We have investigated the availability of zinc in the periplasmic space of Escherichia coli using a mutant Cu,Zn superoxide dismutase whose dimerization is triggered by zinc binding. This mutant enzyme accumulates in the monomeric form when wild type cells are grown in minimal medium, but assembles in the dimeric form when it is produced in the same medium by a mutant strain lacking the periplasmic zinc metallochaperone ZnuA. These results indicate that periplasmic zinc‐containing proteins compete for metal binding when bacteria grow in environments where this element is present in traces. The effective ZnuA ability to sequester the available zinc ions from the periplasm suggests that zinc‐containing cytoplasmic proteins are more important for bacterial viability than the periplasmic ones.
The influence of dipeptide composition on protein thermostability
Authors: Ding Yanrui , Cai Yujie , Zhang Gexin , Xu Wenbo
Published: June 2004

In this work, the influence of dipeptide composition on protein thermostability was studied. After comparing the normalized dipeptide composition between mesophilic proteins and (hyper)thermophilic proteins, we concluded that when organism optimal growth temperature increased, for archaeal proteins, the compositions of VK, KI, YK, IK, KV, KY, and EV increased significantly and the compositions of DA, AD, TD, DD, DT, HD, DH, DR, and DG decreased significantly; and for bacterial proteins, the compositions of KE, EE, EK, YE, VK, KV, KK, LK, EI, EV, RK, EF, KY, VE, KI, KG, EY, FK, KF, FE, KR, VY, MK, WK, and WE increased significantly and the compositions of WQ, AA, QA, MQ, AW, QW, QQ, RQ, QH, HQ, AD, AQ, WL, QL, HA, and DA decreased significantly. So these characteristic dipeptides are correlative to protein thermostability. At the same time, the influence of single amino acid composition on protein thermostability was also studied for comparison. We found that the influence of single amino acid composition could be deduced from the influence of dipeptide composition. So we thought that the influence of dipeptide composition on protein thermostability is larger than the influence of amino acid composition. The characteristic dipeptides not only describe the dipeptides that influence protein thermostability significantly but also show the relationship among significant single amino acids that influence protein thermostability.
ING4 induces G2/M cell cycle arrest and enhances the chemosensitivity to DNA‐damage agents in HepG2 cells
Authors: Zhang Xin , Xu Lu-Sheng , Wang Zhi-Qin , Wang Ke-Sheng , Li Na , Cheng Zhi-Hong , Huang Shang-Zhi , Wei Dong-Zhi , Han Ze-Guang
Published: June 2004

The known members of inhibitor of growth (ING) gene family are considered as candidate tumor suppressor genes. ING4, a novel member of ING family, is recently reported to interact with tumor suppressor p53, p300 (a major component of histone acetyl transferase complexes), and p65(RelA) subunit of NF‐κB. In this study, we investigated the cellular behaviors of HepG2 cells with exogenous ING4. Interestingly, the overexpression of ING4 negatively regulated the cell growth with significant G2/M arrest of cell cycle, and moreover, enhanced the cell apoptosis triggered by serum starvation in HepG2 cells. Furthermore, the exogenous ING4 could upregulate endogenous p21 and Bax in HepG2 cells, not in p53‐deficient Saos‐2 cells, suggesting that G2/M arrest induced by ING4 could be mediated by the increased p21 expression in a p53‐dependent manner, although there is no significant increase of p53 expression in HepG2 cells. Moreover, HepG2 cells with exogenous ING4 could significantly increase cell death, as exposed to some DNA‐damage agents, such as etoposide and doxorubicin, implying that ING4 could enhance chemosensitivity to certain DNA‐damage agents in HepG2 cells.
Structural analysis of DegS, a stress sensor of the bacterial periplasm
Authors: Zeth Kornelius
Published: June 2004

Regulated proteolysis is a key event in transmembrane signalling between intracellular compartments. In Escherichia coli the membrane‐bound protease DegS has been identified as the periplasmic stress sensor for unfolded outer membrane proteins (OMPs). DegS inititates a proteolytic cascade resulting in the release of σ
E the transcription factor of periplasmic genes. The crystal structure of DegS protease reported at 2.2 Å resolution reveals a trimeric complex with the monomeric protease domain in an inhibited state followed by the inhibitory PDZ domain. Noteably, domain architecture and communication of DegS are remarkably to homologous proteins known to date. Here the domain interface is mechanically locked by three intradomain salt bridges. Co‐crystallisation trials in the presence of a 10‐residue activating peptide did not result in significant structural intradomain shifts nor distortions in the crystal packing. These observations imply a mode of activation indicative of peptide‐induced structural shifts imposed to the protease domain rather than disturbing the PDZ–protease interface.
Structures of Bacillus subtilis PdaA, a family 4 carbohydrate esterase, and a complex with N‐acetyl‐glucosamine
Authors: Blair David E , van Aalten Daan M.F
Published: June 2004

Family 4 carbohydrate esterases deacetylate polymeric carbohydrate substrates such as chitin, acetyl xylan and peptidoglycan. Although some of these enzymes have recently been enzymologically characterised, neither their structure nor their reaction mechanism has been defined. Sequence conservation in this family has pointed to a conserved core, termed the NodB homology domain. We describe the cloning, purification and 1.9 Å crystal structure of PdaA, a peptidoglycan deacetylase from Bacillus subtilis. The enzyme assumes a fold related to a (β/α)8 barrel, with a long groove on the surface of the protein that harbours all conserved residues. A complex with the substrate analogue N‐acetyl‐glucosamine was refined to 2.25 Å resolution, revealing interactions of an aspartic acid and three histidines, all conserved in the NodB homology domain, with the ligand. The PdaA structure provides a template for interpreting the wealth of sequence data on family 4 carbohydrate esterases in a structural context and represents a first step towards understanding the reaction mechanism of this family of enzymes.
ErbB3/HER3 does not homodimerize upon neuregulin binding at the cell surface
Authors: Berger Mitchell B , Mendrola Jeannine M , Lemmon Mark A
Published: June 2004

To understand signaling by the neuregulin (NRG) receptor ErbB3/HER3, it is important to know whether ErbB3 forms homodimers upon ligand binding. Previous biophysical studies suggest that the ErbB3 extracellular region remains monomeric when bound to NRG. We used a chimeric receptor approach to address this question in living cells, fusing the extracellular region of ErbB3 to the kinase‐active intracellular domain of ErbB1. The ErbB3/ErbB1 chimera responded to NRG only if ErbB2 was co‐expressed in the same cells, whereas an ErbB4/ErbB1 chimera responded without ErbB2. We, therefore, suggest that ErbB3 is an obligate heterodimerization partner because of its inability to homodimerize.
The presence of a high‐Km hexokinase activity in dog, but not in boar, sperm
Authors: Fernández-Novell Josep M , Ballester Joan , Medrano Antonio , Otaegui Pedro J , Rigau Teresa , Guinovart Joan J , Rodrı́guez-Gil Joan E
Published: June 2004

The presence of a high‐K
m hexokinase activity was tested in both dog and boar spermatozoa. Hexokinase kinetics from dog extracts showed the presence of a specific activity (dog‐sperm glucokinase‐like protein, DSGLP), in the range of glucose concentrations of 4–10 mM, whereas boar sperm did not show any DSGLP activity. Furthermore, dog‐sperm cells, but not those of boar, showed the presence of a protein which specifically reacted against a rat‐liver anti‐glucokinase antibody. This protein also had a molecular weight equal to that observed in rat‐liver extracts, suggesting a close similarity between both the proteins. This glucokinase‐like protein was distributed in the peri‐ and post‐acrosomal zones of the head, and the midpiece and principal piece of tail of dog spermatozoa. These results indicate that dog spermatozoa have functional high‐K
m hexokinase activity, which could contribute to a very fine regulation of their hexose metabolism. This strict regulation could ultimately be very important in optimizing dog‐sperm function along its life‐time.
MyoD–lacZ transgenes are early markers in the neural retina, but MyoD function appears to be inhibited in the developing retinal cells
Authors: Kablar Boris
Published: June 2004

Recent findings suggest that eye and skeletal muscle development in vertebrates share the same regulatory network. In that network, Pax3 gene is apparently activated through Dach/Eya/Six feedback loop to mediate MyoD‐driven myogenesis. The purpose of this study was to investigate previously reported MyoD–lacZ expression in the developing mouse neural retina and to gain insight into the potential role of MyoD in the embryonic retinal cells. The analysis of MD6.0–lacZ and 258/−2.5lacZ transgenic embryos revealed that the retinal temporal expression pattern of the two transgenes resembled their expression pattern in the MyoD‐dependent precursor muscle cells. However, MyoD transcripts and protein could not be found in the sites of MyoD–lacZ retinal expression. Furthermore, our immunohistochemical analysis suggests the existence of diverse factors (e.g., Pax6 and Chx10) within the retinal cells that differentially and inappropriately activate the two transgenes. Finally, the retinal phenotype observed in Pax7−/− knock‐out mice suggests a role for Pax7 in photoreceptor cell differentiation, retinal lamination and in the etiopathology of retinoblastoma. Taken together, our data suggest that the MyoD gene evolved a different mechanism to achieve its down‐regulation within the retina than that of the Myf5 gene.
Situated Experiments in Organizations: Transplanting the Lab to the Field
Authors: Greenberg Jerald , Tomlinson Edward C.
Published: June 2004

Both laboratory and field experiments have limitations that likely account for the recent decline in their usage among organizational researchers. In this article, we introduce situated experiments as an experimental approach that optimizes the strengths of both laboratory and field experiments in organizational research while mitigating the weaknesses of each. We highlight four recently published studies using situated experiments. Drawing on these examples, we illustrate how the proper use of situated experiments can minimize threats to internal validity and ensure the ethical treatment of research participants.
The Applicability of Porter’s Generic Strategies in the Digital Age: Assumptions, Conjectures, and Suggestions
Authors: Kim Eonsoo , Nam Dae-Il , Stimpert J. L.
Published: June 2004

Because current management theories evolved in the context of brick-and-mortar firms, this paper examines three key questions raised by the advent of e-business: (1) Will the strategy types found among e-business firms resemble Porter’s (1980) generic strategies? (2) Will we find performance differences among e-business firms pursuing different types of strategies? (3) Will we find differences in the strategy-performance relationships of pure online firms (pure plays) and firms with both online and offline operations (clicks-and-bricks)? We conclude that integrated strategies that combine elements of cost leadership and differentiation will outperform cost leadership or differentiation strategies. We also argue that, regardless of business strategy type, clicks-and-bricks firms that closely integrate their on-and offline operations will enjoy performance advantages over their pure play counterparts.
Assessing the impact of alternative manufacturing layouts in a service setting
Authors: Pagell Mark , Melnyk Steven A
Published: June 2004

This paper summarizes the results of a project designed to study and ultimately improve the overall operation of a service process, as found in one regional blood center. Driving this project was recognition that the current process, initially designed to accommodate a single customer group, was ill equipped to handle a changing customer mix now consisting of three disparate groups. The resulting mismatch between the process and users created long delays and an increase in the overall level of dissatisfaction with the existing process. To improve overall performance, this study turned to process analysis and computer simulation to stimulate a critical analysis of the process. As part of this approach, the study investigated three layouts: the existing worker paced assembly line, a modified assembly line, and service cells. The study examined the relationship between layout, customer mix and system performance. Key among the results was that a service cell approach led to higher performance and better customer satisfaction.
Prevention and treatment of experimental osteomyelitis in dogs with ciprofloxacin‐loaded crosslinked high amylose starch implants
Authors: Huneault Louis M. , Lussier Bertrand , Dubreuil Pascal , Chouinard Luc , Désévaux Cyril
Published: June 2004

Crosslinked high amylose starch (CLHAS) matrix was used as a biodegradable drug delivery implant for the prevention and treatment of osteomyelitis. Thirty‐two dogs underwent the femoral insertion of a screw inoculated withStaphylococcus aureusand were then randomly assigned to four groups: (A) prevention with ciprofloxacin‐CLHAS implants, (B) surgical debridement (positive control), (C) surgical debridement and oral ciprofloxacin treatment and (D) surgical debridement and treatment with ciprofloxacin‐CLHAS implants. At week 4 the osteomyelitis was confirmed, the infected site debrided and respective treatments initiated for groups B, C and D. Radiographs, macroscopic evaluations, bacterial cultures and histopathological examinations were used to evaluate the femora at week 10. Femora from preventive group A were almost normal. Dogs of both ciprofloxacin treatment groups C and D showed better bone healing, less periosteal reaction and less screw mobility than dogs from group B. Eradication of infection was observed at proximal/distal sites in B: 25%/12%, C: 37%/62% and D: 62%/75%. Both ciprofloxacin treated groups improved radiographically from week 4 to week 10. Periosteal and marrow neutrophilic and lymphoplasmocytic infiltrations were less severe in groups C and D versus group B. These data suggest that biodegradable ciprofloxacin‐CLHAS implants are a safe and efficient modality for the prevention and treatment of osteomyelitis. © 2004 Orthopaedic Research Society. Published y Elsevier Ltd. All rights reserved.
Stable isotopic compositions and fractionations of carbon monoxide at coastal and open ocean stations in the Pacific
Authors: Nakagawa Fumiko , Tsunogai Urumu , Gamo Toshitaka , Yoshida Naohiro
Published: June 2004

Included in this report are the results of the first isotopic studies of seawater‐dissolved carbon monoxide (CO). Large variations in both carbon and oxygen isotopic compositions (δ13C: −44.7 ∼ −21.1‰PDB, and δ18O: +8.7 ∼ +32.9‰SMOW) were observed in seawater‐dissolved CO due to the combination of isotopically light CO production in seawater and the enrichment of heavy isotopes during the microbial consumption of CO. Compared with the total δ13C value of dissolved organic matter (DOM), the isotopic compositions of the photochemically produced CO in seawater are depleted in 13C by more than 20‰, probably due to large fractionation processes during the photochemical production of CO from DOM. In addition, the isotopic fractionation factors resulting from the microbial oxidation of CO in seawater were estimated to be 1.005 ± 0.002 and 1.006 ± 0.002 for carbon (αc) and oxygen (αo) based on the incubation experiments. By calculating the weighted mean of the isotopic composition of CO according to the CO concentration observed in surface seawater, the mean δ13C and δ18O for CO emitted from the oceans were estimated to be −40‰ PDB and +15‰ SMOW, respectively. Oceanic CO is a unique source of 13C and 18O‐depleted CO relative to that of fossil fuel combustion and biomass burning, which will help us create a better isotopic mass balance for both global and local CO budget.
The secular imprint of the interplanetary magnetic field drift on 10Be data
Authors: Valdés‐Galicia J. F. , Mendoza B.
Published: June 2004

We perform an analysis of the evolution of the 10Be and the geomagnetic aa index in the common period 1868–1990. Correlations of the whole period do not produce a very high correlation coefficient (r = 0.45). However, separating the data sets according to the different phases of the solar cycle leads to a good correlation between 10Be and aa for negative (A < 0) polarity and a low correlation for the positive (A > 0) polarity. The 10Be data is found to be statistically different between positive and negative polarity times. However, no difference is found for the aa index of the two alternative solar magnetic polarities. These facts evidence the solar magnetic field drift effects on cosmic rays over the 11 solar cycles spanning this work.
Accreted terranes of northwestern British Columbia, Canada: Lithospheric velocity structure and tectonics
Authors: Hammer Philip T. C. , Clowes Ron M.
Published: June 2004

Lithospheric structure beneath the accreted terranes of the northwestern Canadian Cordillera is interpreted from analyses of P wave refraction and wide‐angle reflection data. The 535 km long profile extends from the deformed and displaced ancestral North American margin across the Omineca belt suture zone and Intermontane superterrane to the Coast belt. This region is interpreted to have grown westward through a progression from thin‐skinned to thick‐skinned accretionary tectonics. Large lateral variations of velocities (2.0–6.4 km/s) within the upper 15 km correlate with the mapped geological and terrane elements; fault offsets and the imbricated base of an overlap basin are clearly identified. Inboard of the Stikine accreted terrane a zone of slow upper crustal velocities thins to the east, consistent with an interpretation of thin‐skinned accretion leaving slivers of terranes overlying a wedge of metamorphosed Proterozoic continental margin sediments. However, in the lower crust the proposed underlying cratonic ramp is not distinguished from outboard or overlying accreted crust by lateral P velocity contrasts or wide‐angle reflections. The Moho remains nearly horizontal beneath the Intermontane and Omineca belts, gradually thinning to the east from 36.5 to 35 km. To the southwest below the Coast belt and to the northeast beneath the Tintina fault, the crust thins to 32 km. Upper mantle velocities across the Coast, Intermontane, and Omineca belts are 7.8–7.9 km/s. The slow upper mantle and lower crustal velocities are indicative of high temperatures that may permit the flat Moho or weak lower crust to partially decouple the crust from the mantle. Reflections in the upper mantle between 50–70 km depth may be related to the base of the lithosphere or to heterogeneities introduced through melting or accretionary subduction events.
Generalized hydraulic geometry: Derivation based on a multiscaling formalism
Authors: Dodov Boyko , Foufoula‐Georgiou Efi
Published: June 2004

Relationships between channel characteristics (e.g., mean depth, water surface width, mean velocity) and discharge, known as hydraulic geometry (HG), have been extensively used by hydrologists and geomorphologists since the seminal work of Leopold and Maddock [1953]. On the basis of recent empirical evidence that the parameters of at‐site HG depend systematically on the contributing area (scale) and that the parameters of downstream HG depend on the frequency of discharge, we propose a multiscaling formalism within which to model and interpret both at‐site and downstream HG in a homogeneous region. In particular, we postulate and test multiscaling models for cross‐sectional area and discharge and derive generalized HG relationships that explicitly account for scale‐frequency dependence. The multiscaling formalism is tested in several basins in Oklahoma and Kansas for drainage areas ranging from 2 to 20,000 km2 and shows good agreement with the data. To quantify the effects that scale dependence in HG has on the hydrologic response of a basin, a geomorphologic nonlinear cascade of reservoirs model has been used to compute attributes of a representative hydrologic response function for various levels of catchment‐averaged effective rainfall and different basin orders. The numerical experiment shows substantial differences in hydrologic response when using classical versus generalized HG. Finally, a preliminary effort is reported to generalize even further the HG relationships such that they can account for deviations from a single power law (e.g., consideration of two different power laws in low‐ and high‐flow regimes) through the introduction of a bivariate mixed multiscaling framework.
Chlorofluorocarbons in a global ocean eddy‐resolving OGCM: Pathway and formation of Antarctic Bottom Water
Authors: Sasai Yoshikazu , Ishida Akio , Yamanaka Yasuhiro , Sasaki Hideharu
Published: June 2004

We have investigated the pathway of Antarctic Bottom Water (AABW) using simulated chlorofluorocarbons (CFCs) distribution in a global eddy‐resolving OGCM. Our goal is to improve our understanding of the processes and pathways determining the distribution of CFCs in the Southern Ocean, where much of this tracer is entrained by formation of the deep and bottom water. The model exhibits considerable skill in reproducing the section along the Greenwich Meridian (AJAX) and 170°W (WOCE P15S). In the South Atlantic, the model indicates two pathways transporting CFC‐11 from the Weddell Sea to the AJAX section: an upper pathway through the Scotia Sea, and a lower pathway south along the South Scotia Ridge. The simulated CFC‐11 inventory along the two sections is much like that observed.
Dating pseudotachylyte of the Nojima fault using the zircon fission‐track method
Authors: Murakami Masaki , Tagami Takahiro
Published: June 2004

The zircon fission‐track analysis of pseudotachylyte answered how old the Nojima fault is, which was activated during the 1995 Kobe earthquake in Japan. The time of seismic fault motions at the crustal interior can be constrained by dating pseudotachylyte formation. We succeeded in separating zircons from the pseudotachylyte layer of the fault as well as in dating them by the fission‐track method. Here we show that the layer has a significantly younger age (56 ± 4 Ma) than the initial cooling age of the host rock, suggesting that the fault was already initiated at ∼56 Ma, much older than the previous estimate based on the spatial distribution of sediments around the fault.
The flux of iron from continental shelf sediments: A missing source for global budgets
Authors: Elrod Virginia A. , Berelson William M. , Coale Kenneth H. , Johnson Kenneth S.
Published: June 2004

The flux of dissolved iron from sediments to the water column was measured with flux chambers along the California coast over a five‐year period. High fluxes were observed from sediments on the continental shelf. The measured fluxes were an average of 75 times larger than flux values derived from pore‐water iron gradients. The iron flux was significantly correlated with the oxidation of organic matter, which allows an extrapolation to the global shelf. The input from shelf sediments is at least as significant as the global input of dissolved iron from aerosols, which has been presumed to be the dominant external iron source. Evidence of this input is seen 100's of kilometers offshore where it can enable the high productivity of broad coastal regions seen in satellite images.
Imperfect K Index Satisfactory For Electric Power Industry
Authors: Oler Cary
Published: June 2004

The 2004 Space Weather article, “Does the electrical power industry need better storm warnings?” is a good description of the argument that the geomagnetic scale known as the K index is inadequate for the power industry. While the K index is not ideal, what we need is not yet practical. For now at least, the K index is one of the most easily understood, best researched, and applicable indices of magnetic activity for the power industry.
Upregulation of orphan nuclear receptor Nur77 following PGF2α, Bimatoprost, and Butaprost treatments. Essential role of a protein kinase C pathway involved in EP2 receptor activated Nur77 gene transcription
Authors: Liang Yanbin , Li Chen , Guzman Victor M , Chang William W , Evinger Albert J , Pablo Jozelyn V , Woodward David F
Published: June 2004

Using gene chip technology, we first identified that PGF2α (FP agonist) and Butaprost (EP2 agonist) induced about a five‐fold upregulation of Nur77 mRNA expression in hFP‐HEK 293/EBNA and hEP2‐HEK293/EBNA cells. Northern Blot analysis revealed that PGF2α‐ and Butaprost‐induced upregulation of Nur77 expression are dose‐ and time‐dependent.

Both PGF2α and Butaprost upregulated Nur77 gene expression through the protein kinase C (PKC) pathway. These data are the first showing a link between EP2 receptor stimulation and protein kinase C activation. Calcineurin was found to be involved downstream of the PKC pathway in PGF2α‐induced Nur77 expression, but not in Butaprost‐induced Nur77 expression.

We also used Nur77 as a marker gene to compare the effects of PGF2α, Butaprost, and Bimatoprost (a prostamide) on Nur77 expression in human primary trabecular meshwork and ciliary smooth muscle (SM) cells, which are target cells for antiglaucoma drugs. The results showed that PGF2α and Butaprost, but not Bimatoprost, induced upregulation of Nur77 expression in human TM cells. PGF2α, but not Bimatoprost, dramatically induced upregulation of Nur77 mRNA expression in human ciliary SM cells, whereas Butaprost slightly upregulated Nur77 mRNA expression in SM cells.

Nur77 promoter deletion analysis indicated that PGF2α, but not Bimatoprost, activated Nur77 promoter‐luciferase reporter in hFP‐HEK 293/EBNA cells. Butaprost was less efficacious in inducing Nur77 promoter‐luciferase reporter activity in hEP2‐HEK293/EBNA cells relative to PGF2α in the comparable assay. The data for Nur77 promoter functional analysis were matched to the Northern blot analysis.

It appears that PGF2α and Butaprost activate Nur77 transcription mechanisms through the activation of FP and EP2 receptor‐coupled signaling pathways, whereas Bimatoprost stimulates neither FP nor EP2 receptors.

British Journal of Pharmacology (2004) 142, 737–748. doi:10.1038/sj.bjp.0705829
Wine polyphenols induce hypotension, and decrease cardiac reactivity and infarct size in rats: involvement of nitric oxide
Authors: Ranaivo Hantamalala Ralay , Diebolt Myriam , Andriantsitohaina Ramaroson
Published: June 2004

The effects of short‐term oral administration of red wine polyphenolic compounds (RWPC, 20 mg kg−1 day−1 for 7 days) on haemodynamics, ex vivo cardiac responsiveness and ischaemia–reperfusion injury were investigated in rats. The involvement of nitric oxide (NO) was evaluated using the NO synthase inhibitor, NG‐nitro‐L‐arginine methyl ester (L‐NAME, 2 mg kg−1 day−1 for 7 days), at a dose which did not affect blood pressure.

Ex vivo reactivity of hearts from RWPC‐treated rats showed lower basal developed pressure, greater heart rate and decreased inotropic responses to either β‐adrenoceptor or muscarinic receptor stimulation with isoprenaline or carbachol, respectively.

RWPC treatment did not modify cardiac expression of endothelial NO synthase or Cu/Zn superoxide dismutase. However, it increased nitrite in the coronary effluent.

In ischaemia–reperfusion, RWPC treatment reduced infarct size and oxidative stress, as shown by the myocardial content of the end products of lipid peroxidation, malondialdehyde and 4‐hydroxynonenal, without affecting post‐ischaemic contractile dysfunction. All the observed effects of RWPC were prevented by L‐NAME treatment.

Altogether, these data show that short‐term treatment with RWPC decreases blood pressure and cardiac responsiveness, and protects against post‐ischaemic infarction via decreased oxidative stress. All the above effects of RWPC are sensitive to NO synthase inhibition that implies an involvement of NO‐dependent pathway. This study suggests a basis for the beneficial effects of plant‐derived polyphenols against cardiovascular disease.

British Journal of Pharmacology (2004) 142, 671–678. doi:10.1038/sj.bjp.0705833
Attenuation by a sigma1 (σ1) receptor agonist of the learning and memory deficits induced by a prenatal restraint stress in juvenile rats
Authors: Meunier Johann , Gué Michèle , Récasens Max , Maurice Tangui
Published: June 2004

Stress during pregnancy results in complex neurochemical and behavioral alterations throughout the offspring lifetime. We here examined the impact of prenatal stress (PS) on memory functions in male and female offspring and report the efficacy of a selective sigma1 (σ1) receptor agonist, igmesine, in alleviating the observed deficits.

Dams received an unpredictable 90‐min duration restraint stress from gestational day E17 to E20. Learning was examined in offspring between day P24 and P36 using spontaneous alternation in the Y‐maze, delayed alternation in the T‐maze, water‐maze learning and passive avoidance.

Both male and female PS rats showed impairments of spontaneous and delayed alternation performances. Acquisition of a fixed platform position in the water‐maze was unchanged in PS rats, but the probe test revealed a diminution of time spent in the training quadrant. Acquisition of a daily changing platform position demonstrated impaired working memory for male and female PS rats. Finally, passive avoidance deficits were observed.

Pretreatment with the selective σ1 agonist igmesine (1–10 mg kg−1 i.p.) reversed the PS‐induced learning deficits in offspring rats for each test. The σ1 antagonist BD1063 failed to affect performances alone but blocked the igmesine effect, confirming the involvement of the σ1 receptor.

PS thus induces delayed memory deficits, affecting spatial and nonspatial, short‐ and long‐term memories in juvenile male and female offspring rats. Activation of the σ1 neuromodulatory receptor allows a significant recovery of the memory functions in PS rats.

British Journal of Pharmacology (2004) 142, 689–700. doi:10.1038/sj.bjp.0705835
Depolarization‐induced calcium influx in rat mesenteric small arterioles is mediated exclusively via mibefradil‐sensitive calcium channels
Authors: Jensen Lars J , Salomonsson Max , Jensen Boye L , Holstein‐Rathlou Niels‐Henrik
Published: June 2004

In this study, intracellular Ca2+ was measured as the Fura‐2 ratio (R) of fluorescence excited at 340 and 380 nm (F340/F380) in nonpressurized rat mesenteric small arterioles (Ø (lumen diameter) 10–25 μm). The response to depolarization using 75 mM KCl was an increase in R from a baseline of 0.96±0.01 ([Ca2+]i ∼74 nM) to 1.04±0.01 (∼128 nM) (n=80).

The response to 75 mM K+ was reversibly abolished in Ca2+‐free physiological saline solution, whereas phentolamine (10 μM) or tetrodotoxin (1 μM) had no effects. LaCl3 (200 μM) inhibited 61±9% of the response.

A [K+]‐response curve indicated that the Ca2+ response was activated between 15 and 25 mM K+. The data suggest that the Ca2+ response was caused by the activation of voltage‐dependent Ca2+ channels.

Mibefradil use dependently inhibited the Ca2+ response to 75 mM K+ by 29±2% (100 nM), 73±7% (1 μM) or 89±7% (10 μM). Pimozide (500 nM) use dependently inhibited the Ca2+ response by 85±1%.

Nifedipine (1 μM) inhibited the Ca2+ response to 75 mM K+ by 41±12%. The response was not inhibited by calciseptine (500 nM), ω‐agatoxin IVA (100 nM), ω‐conotoxin MVIIA (500 nM), or SNX‐482 (100 nM).

Using reverse transcriptase–polymerase chain reaction, it was shown that neither CaV2.1a (P‐type) nor CaV2.1b (Q‐type) voltage‐dependent Ca2+ channels were expressed in mesenteric arterioles, whereas the CaV3.1 (T‐type) channel was expressed. Furthermore, no amplification products were detected when using specific primers for the β1b, β2, or β3 auxiliary subunits of high‐voltage‐activated Ca2+ channels.

The results suggest that the voltage‐dependent Ca2+ channel activated by sustained depolarization in mesenteric arterioles does not classify as any of the high‐voltage‐activated channels (L‐, P/Q‐, N‐, or R‐type), but is likely to be a T‐type channel. The possibility that the sustained Ca2+ influx observed was the result of a T‐type window current is discussed.

British Journal of Pharmacology (2004) 142, 709–718. doi:10.1038/sj.bjp.0705841
Endothelin‐induced constriction of the ductus venosus in fetal sheep: developmental aspects and possible interaction with vasodilatory prostaglandin
Authors: Adeagbo A S O , Kelsey L , Coceani F
Published: June 2004

The ductus venosus is actively regulated in the fetus, but questions remain on the presence of a functional sphincter at its inlet. Using fetal sheep (0.6–0.7 gestation onwards), we have examined the morphology of the vessel and have also determined whether endothelin‐1 (ET‐1) qualifies as a natural constrictor being modulated by prostaglandins (PGs).

Masson's staining and α‐actin immunohistochemistry showed a muscular, sphincter‐like formation at the ductus inlet and a muscle layer within the wall of the vessel proper. This muscle cell component increased with age.

ET‐1 contracted dose‐dependently isolated sphincter and extrasphincter preparations of the ductus from term fetus. This ET‐1 effect also occurred in the premature, but its threshold was higher.

BQ123 (1 μM) caused a rightward shift in the ET‐1 dose–response curve, while indomethacin at a threshold concentration (28 nM) tended to have an opposite effect.

Big ET‐1 also contracted the ductus sphincter but differed from ET‐1 for its lesser potency and inhibition by phosphoramidon (50 μM).

The ductus sphincter (term and preterm) and extrasphincter (term) released 6‐keto‐PGF1α (hence PGI2) and, to a lesser degree, PGE2 at rest and their release increased dose‐dependently upon ET‐1 treatment. Both basal and stimulated release was curtailed by endothelium removal.

BQ123 and phosphoramidon reduced slightly the contraction of ductus sphincter to indomethacin (2.8 μM).

We conclude that the ductus contains a contractile mechanism in the sphincter and extrasphincter regions. ET‐1 lends itself to a role in the generation of contractile tone and its action may be modulated by prostaglandins.

British Journal of Pharmacology (2004) 142, 727–736. doi:10.1038/sj.bjp.0705849